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Antioxidant activity of low molecular weight hyaluronic acid

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Abstract

Two polysaccharides, low molecular weight hyaluronic acid-1 (LMWHA-1) and LMWHA-2, with their molecular weight of 1.45×10(5) and 4.52×10(4)Da, respectively, were prepared from high molecular weight hyaluronic acid (HA,1.05×10(6)Da). LMWHA-1, LMWHA-2 and HA were studied for their antioxidant activities. In vitro antioxidant assay, LMWHA showed strong inhibition of lipid peroxidation and scavenging activities of hydroxyl radical, moderate 1,1-diphenyl-2-picryldydrazyl radical and superoxide anion scavenging activity. In addition, the LMWHA-1 exhibited much stronger antioxidant activity than LMWHA-2 and HA. For antioxidant testing in vivo, LMWHA-1, LMWHA-2 and HA were orally administrated over a period of 7days in a cyclophosphamide(CY) induced immunosuppressed mice model. As results, administration of LMWHA was able to overcome CY-induced immunosuppression and significantly raised the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and total antioxidant capacity (TAOC) in immunosuppressed mice. The results showed that the LMWHA, possessing pronounced free radical scavenging and antioxidant activities.

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... We observed a significant difference (p < 0.001) between LMWHA and HA in antioxidation ability, which showed that the radical scavenging capacity of LMWHA is significantly stronger than that of HA per the results of the above four indicators. The antioxidant ability of LMWHA is better than that of HA [34][35][36]. However, the enhanced antioxidant capacity of the cleavage products of hyaluronic acid lyases was not clearly explained in terms of molecular properties. ...
... We observed a significant difference (p < 0.001) between LMWHA and HA in antioxidation ability, which showed that the radical scavenging capacity of LMWHA is significantly stronger than that of HA per the results of the above four indicators. The antioxidant ability of LMWHA is better than that of HA [34][35][36]. However, the enhanced antioxidant capacity of the cleavage products of hyaluronic acid lyases was not clearly explained in terms of molecular properties. . ...
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The Gram-negative strain of Citrobacter freundii, YNLX, has the ability to degrade hyaluronic acid. In this study, we expressed a C. freundii hyaluronic acid lyase, from polysaccharide lyase family 8, in Escherichia coli. The purified recombinant enzyme (rHynACF8) showed a substantially higher cleavage activity of hyaluronic acid than chondroitin sulfate. We found that its optimal pH and temperature are 5.5 and 35 °C, respectively. In addition, the enzyme activity was not notably affected by most metal ions. Km and kcat of rHynACF8 towards HA were 1.5 ± 0.01 mg/mL and 30.9 ± 0.5 /s, respectively. rHynACF8 is an endo-acting enzyme. Its cleavage products had dramatically increased antioxidant activity than hyaluronic acid in vitro (p < 0.001). As the molecular weight of hyaluronic acid decreased, the intramolecular interactions among antioxidant functional groups were removed; in the process of the cracking reaction, new double bonds formed and conjugated with the carbonyl group. We presumed that the structural change is the critical factor influencing antioxidant capacity. Overall, we found that rHynACF8 from Gram-negative bacteria with metal ion resistance, indicated the relationship between the function and structure of its antioxidant cleavage product.
... Hyaluronic acid is a nonsulfated glycosaminoglycan that is the main constituent of the extracellular matrix (Williams et al. 2019). Ke et al. (2011) revealed that its low molecular weight variant is an antioxidant with free radical scavenging activity. Previous studies also reported that it is effective for inhibiting lipid peroxidation and has the potential as a cryoprotectant in pig sperm (Qian et al. 2016). ...
... But, hyaluronic acid, also known as an antioxidant, inhibits lipid peroxidation (Braga et al. 2015;Qian et al. 2016). Low molecular hyaluronic acid showed strong inhibition of lipid peroxidation and scavenging activities of hydroxyl radical (Ke et al. 2011). One method of protection hyaluronic acid is known to perform is neutralizing free radicals, all reactions between ROS and hyaluronan result in the fragmentation of the hyaluronic acid chain (Dovedytis et al. 2020). ...
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Gaga' chicken (Gallus gallus domesticus) is Indonesian germplasm that needs to be preserved with cryopreservation technology. Therefore, this study aims to determine the effect of adding L-Carnitine, hyaluronic acid, and sucrose as well as their combination in a diluent on the quality of Gaga' chicken spermatozoa after freeze-thawing. A completely randomized design was used along with 6 treatments, namely P0, P1, P2, P3, P4, and P5, containing Ringer acetate-egg yolk (RAEY) diluent (P0), RAEY + 0.063 mM hyaluronic acid (P1), RAEY + 1 mM L-carnitine (P2), RAEY + 1 mM sucrose (P3), RAEY + 0.063 mM hyaluronic acid + 1 mM L-carnitine (P4), and RAEY + 0.063 mM hyaluronic acid + 1 mM L-carnitine + 1mM sucrose (P5). Liquid semen was packed in a 0.25 mL straw, equilibrated at 5 o C for 2 hours, and placed 3 cm above the surface of liquid nitrogen for 10 minutes. It was then immersed in nitrogen for 24 hours and thawed at 60°C for 5 seconds. The results showed that there was a significant difference (P<0.05) in the motility, viability, and kinematic variables of spermatozoa after freeze-thawing. P1, P2, P3, and P4 increased progressive motility, P1 and P4 increased curvilinear velocity, while viability increased with P4 treatment. Furthermore, the addition of Hyaluronic acid, L-carnitine, or their combination in the RAEY diluent can improve the sperm quality of Gaga' chickens.
... Hence, the antioxidant activity of HA was lower than mangosteen peel extract. In contrast, Ke et al. [67] demonstrated that 1600 µg/mL low molecular weight hyaluronic acid-1 (LMWHA-1), HA and LMWHA-2 showed DPPH radical scavenging activity of 59.38%, 53.65% and 50.23%, respectively. The differences in free radical scavenging activity of HA may be due to the variation in their molecular weight. ...
... The differences in free radical scavenging activity of HA may be due to the variation in their molecular weight. In this study, the molecular weight of HA was 8-15 kDa, whereas Ke et al. [67] utilized LMWHA-1, LMWHA-2 and HA with molecular weights of 1.45 × 10 5 Da, 4.52 × 10 4 Da and 1.05 × 10 6 Da, respectively. However, the relationship between antioxidant activity and the molecular weight of HA requires further investigation. ...
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The widely reported adverse effects of synthetic ingredients encourage the development of green cosmeceuticals to achieve Sustainable Development Goal (SDG) 3. The waste product of mangosteen (mangosteen peel) was utilized in the formulation to reduce waste production corresponding to SDG 12, in addition to its anti-aging and pigmentation control effects. This study aimed to formulate and evaluate novel herbal face creams containing standardized mangosteen peel extract. The mangosteen creams were formulated using natural ingredients and were evaluated for their organoleptic characteristics, rheology, spreadability and pH. Furthermore, an accelerated stability study, freeze–thaw stability study and centrifugation test were conducted. In addition, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assays were conducted to assess its antioxidant effects, whereas tyrosinase inhibitory assay was conducted to determine its anti-tyrosinase activity. The formulated creams appeared light yellowish-brown and homogenous without phase separation. The creams displayed shear-thinning behavior and optimal pH which was ideal for topical application. The creams were stable after being subjected to various stability tests and were shown to have antioxidant and anti-tyrosinase activity. In conclusion, the development of mangosteen-based green cosmeceutical face cream is in line with SDG 3 and 12. It is expected to be used as a safe and effective alternative to synthetic products.
... HA could be utilized as a food ingredient to increase the water retention and rheological qualities of meat emulsions, as well as a replacement for polyphosphates, carrageenan, and soy protein, enabling for the creation of novel healthy meat products [20]. In recent years, a number of scientific investigations have demonstrated that In vitro and in vivo, HA exhibits antioxidant effects [21]. ...
... Free radicals may interact with these organizations [23]. This outcome was consistent with previous research by [21], where the DPPH scavenging capability of HA (1050 kDa) and LMWHA-1 (145 kDa) were 53.63%, 59.38%, respectively, at 1.6 mg/ml. ...
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The synthesis of hyaluronic acid (HA) by bacteria is a promising alternative to extracting the biopolymer from animal tissues. The production of HA by Streptococcus thermophilus, which belongs to the group of organisms generally recognized as safe (GRAS), is a well-studied viable alternative. The present study investigated five S. thermophilus strains (St1, St2, St3, St4, and St5) with markedly high HA productivity. The quantity of purified HA was different following the order St5 > St4 > St3 > St2 > St1. The characteristics of molecular mass analysis of HAs were evaluated by multi-technique (FTIR, NMR, and HPLC). The antioxidant activity of the purified HA was quantified by multi-technique (DPPH, iron chelating, reducing power, and hydrogen peroxide (H2O2) scavenging activity), over a range of relevant concentrations, i.e., 50, 100, 300, 500, 700, 1100, and 1300 µg/ml. They were tested for a concentration-dependent enhancement in their radical scavenging and lowering abilities. Significantly increased antioxidant activity was detected at concentrations of 1300 µg/ml, with 69.18%, 78.42%, and 73.74% of DPPH, hydrogen peroxide, and iron-chelating scavenging activities, respectively. Furthermore, HA was proven to have effective lowering power at the same concentration. When compared to the typical antioxidant Butylated hydroxytoluene (BHT), but these various antioxidant activities were low. It is suggested that HA have the potential to be the resource of natural antioxidant.
... [15] Several studies have shown the HA antioxidant properties in vitro and in vivo. [16][17][18] However, to the best of our knowledge, there is no investigation comparing physicochemical characteristics and antioxidant activities of HA produced by microbial synthesis with that extracted from animal tissues. In this context, the present study aimed to evaluate the physicochemical characteristics and in vitro antioxidant activities of hyaluronic acid produced by Streptococcus zooepidemicus CCT 7546 and from an animal source. ...
... Pan et al. [16] showed a scavenging DPPH of 41% for HA produced by S. zooepidemicus at 1.0 g/L. In addition, Ke et al. [18] described the highest DPPH radical scavenging activities of 59.38% for low molecular weight hyaluronic acid. On the other hand, no activity was detected in the superoxide radical scavenging test in the present study ( Table 3). ...
Article
Hyaluronic acid (HA) is a biopolymer with applications in different areas such as medicine and cosmetics. HA is currently either isolated from animal sources or produced by microbial fermentation. Animal HA presents some disadvantages such as high cost and risk of viral cross-species or another infectious agent. In the present study, we evaluated the physicochemical characteristics and in vitro antioxidant capacity of HA produced by Streptococcus zooepidemicus CCT 7546. In addition, commercial sodium hyaluronate (SH) from an animal source was used as control. The microbial HA yield after purification was 69.8 mg/L. According to Fourier transform infrared spectroscopy, it was seen that bacterial and animal HA spectra are overlapped. The thermogravimetric analysis revealed that microbial HA was more stable than its equivalent from the animal source. However, scanning electron microscopy indicates that the purification method used in the animal product was more effective. Microbial HA showed activity in total antioxidant capacity (14.02 ± 0.38%), reducing power (18.18 ± 6.43%), DPPH radical-scavenging (5.57 ± 0.23 kmol TE/g), and hydroxyl radical-scavenging (28.39 ± 2.40%) tests. Therefore, in vitro antioxidant tests demonstrated that the antioxidant action mechanism occurs through scavenging reactive oxygen species (ROS) and donating electrons/hydrogen atoms.
... Irradiation of gamma rays to the native hyaluronic acid increased its antioxidant activity by reducing the molecular weight [134]. Two LMWHAs, LMWHA-1 (145 kDa) and LMWHA-2 (45.2 kDa), inhibit lipid peroxidation and scavenge hydroxyl radical 1,1-diphenyl-2-picryldydrazyl radical superoxide anion in vitro [135]. Its antioxidant and free radical scavenging properties were superior to that of the native hyaluronic acid of 1050 kDA. ...
... Its antioxidant and free radical scavenging properties were superior to that of the native hyaluronic acid of 1050 kDA. Administration of LMWHA increased the activity of SOD, catalase, glutathione peroxidase, and total antioxidant capacity in cyclophosphamide-induced immunosuppressed mice [135]. However, the mechanism of antioxidant effect of LMWHA needs further study. ...
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Antioxidants may modulate the microenvironment of epidermal stem cells by reducing the production of reactive oxygen species or by regulating the expression of extracellular matrix protein. The extracellular membrane is an important component of the stem cell niche, and microRNAs regulate extracellular membrane-mediated basal keratinocyte proliferation. In this narrative review, we will discuss several antioxidants such as ascorbic acid, plant extracts, peptides and hyaluronic acid, and their effect on the epidermal stem cell niche and the proliferative potential of interfollicular epidermal stem cells in 3D skin equivalent models.
... 48 HA, as a macromolecular polysaccharide, also has the antioxidant capacity and has a role in scavenging ROS in vivo. 49 According to our experimental results, SIN-L-H had a good scavenging ability on DPPH and H 2 O 2 In vitro, and it also had an obvious inhibitory effect on MDA in organs. Therefore, in the treatment of oxidative stress, the combination of SIN, phospholipids, and HA will be an excellent choice, and SIN-L-H might be a good antioxidant for the clinic in the future. ...
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Sinomenine (SIN), a natural product, has been used to treat rheumatoid arthritis (RA) in China for thousands of years. SIN has been developed for the treatment of RA by way of tablets and injections, but both dosage forms have been associated with severe adverse reactions. Making SIN into liposomes-in-hydrogel biomaterials for external use has a good slow-release effect and can play an important role in avoiding the first-pass effect, gastrointestinal reaction, and increasing the local action time of drugs. SIN-loaded liposomes were formed by the thin-film dispersion method, then SIN-loaded liposomes-in-hydrogels were prepared by combining the SIN-L with hyaluronic acid (HA) hydrogels. In this paper, the basic characteristics, In vitro and Ex vivo release, and antioxidant activity of SIN-loaded liposomes-in-hydrogels were studied. The results showed that SIN-loaded liposomes-in-hydrogels have good sustained-release and antioxidant effects, and the preparation is expected to be a good biomaterial.
... In this study, AKP activity was highest at 2.73% dietary Arg levels. Furthermore, antioxidant enzymes (e.g., SOD, CAT, and T-AOC) play a direct role in removing excess ROS and protecting cells from oxidative damage (Ke et al., 2011;Ighodaro and Akinloye, 2018). T-AOC can be used as a comprehensive index to assess the antioxidant capacity of the body. ...
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This study investigated the effects of different dietary arginine (Arg) levels on the growth, protein synthesis, antioxidant capacity, and immunity of postlarval mud crab Scylla Paramamosain . Six isonitrogenous and isolipidic diets were formulated to contain 1.51%, 1.81%, 2.16%, 2.35%, 2.73%, and 3.07% dietary Arg levels (dry matter). There were four replicates for each diet treatment (26 crabs per replicate, initial body weight: 7.40 ± 0.15 mg). After eight weeks of feeding trial, the survival and molting frequency (MF) of crabs were not affected by the experimental treatment ( P >0.05). Crabs fed the 2.50% Arg diet achieved the highest weight gain (WG) and specific growth rate (SGR) ( P <0.05). The whole-body protein content of the 2.16% and 2.73% Arg groups were significantly higher than that of the 1.51% Arg group ( P <0.05). Crabs in the 2.35% group obtained the highest levels of phenylalanine and leucine ( P <0.05). Superoxide dismutase (SOD), catalase (CAT), and total antioxidant capacity (T-AOC) activity in the 2.16%, 2.35% and 2.73% Arg groups were significantly higher than that in other treatments ( P <0.05). Malondialdehyde (MDA) concentration and alkaline phosphatase (AKP) activity were not significantly affected by the treatments. The transcript levels of insulin-like growth factor 1 ( igf-1 ), rapamycinin ( TOR ), S6 kinase-polypeptide 1 ( s6k1 ) in crabs fed with 2.16% and 2.35% dietary Arg were significantly higher than those in crabs fed with 1.51% and 3.07% dietary Arg ( P <0.05). The lowest prophenoloxidase ( proPO ), relish , and lysozyme transcript levels were observed in crabs fed the 1.51% dietary Arg. The current study founded that the Arg requirement for postlaval S.paramamosain was 2.34% (5.20% of the dietary protein), based on the second order polynomial regression analysis of WG.
... Scientists have found, that hyaluronic acid derivatives have antioxidant activity [61]. In a study conducted by Chunlin et al., it was found that low molecular weight hyaluronic acid derivatives exhibited antioxidant activity and that the compounds were able to reduce lipid peroxidation [62]. In this experiment, we investigated the antioxidant activity of 0.1% (~1.5-1.8 × 10 6 Da) hyaluronic acid in the formulations. ...
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Phenolic compounds of natural origin have been valued for their beneficial effects on health since ancient times. During our study, we performed the extraction of phenolic compounds from balsam poplar buds using different concentrations of aqueous polyethylene glycol 400 solvents (10–30% PEG400). The aqueous 30% PEG400 extract showed the best phenolic yield. The stability of the extract during autoclave sterilization was evaluated. The extract remained stable under heat sterilization. Ophthalmic formulations are formed using different concentrations (8–15%) of poloxamer 407 (P407) together with hydroxypropyl methylcellulose (0.3%), sodium carboxymethyl cellulose (0.3%) or hyaluronic acid (0.1%). Physicochemical parameters of the formulations remained significantly unchanged after sterilization. Formulations based on 12% P407 exhibited properties characteristic of in situ gels, the gelation point of the formulations was close to the temperature of the cornea. After evaluating the amount of released compounds, it was found that, as the concentration of polymers increases, the amount of released compounds decreases. Formulations based on 15% P407 released the least biologically active compounds. Sterilized formulations remained stable for 30 days.
... HA was also found to enhance peripheral nerve regeneration in the frog (5). In addition, several reports showed that HA possessed free radical scavenging and antioxidant activities in vivo and in vitro settings (6)(7)(8). Reactive oxygen species (ROS) have been proven as endogenous mediators of muscle fatigue and possibly involved in chronic fatigue syndrome (9, 10). ...
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Hyaluronan (HA) is a mucopolysaccharide that naturally exists in all living organisms as the main component of the extracellular matrix. Over the last 30 years, HA has been used as the main ingredient in cosmetic products, eye drops, and medicinal products. It is also taken orally as a health supplement. However, the physiological effect of the ingested HA is not clear. In the current study, the interaction between HA and gut microbiota, and the potential prebiotic effects were investigated. HA was used to treat the C57BL/6 mice for 15 consecutive days, then fecal genomic DNA was extracted from fecal samples for 16S rRNA amplicon sequencing. The results showed that HA could significantly change the composition of gut microbiota (GM), e.g., increased the relative abundance of beneficial bacteria, including short-chain fatty acids (SCFAs)-producing bacteria and xylan/cellulose-degrading bacteria, whereas decreased the relative abundance of potential pathogens including sulfate-reducing bacteria (SRB), inflammation and cancer-related bacteria. The rotarod test was used to evaluate the anti-fatigue effects of HA in C57BL/6 mice. The results showed that HA could lengthen the mice's retention time on the accelerating rotarod. HA increased the concentration of glycogen and superoxide dismutase (SOD) in mice's muscle and liver, whereas decreased the serum concentration of malondialdehyde (MDA). Moreover, the metabolic products of Desulfovibrio vulgaris (MPDV), the model SRB bacteria, showed cytotoxic effects on H9c2 cardiomyocytes in a dosage-dependent manner. MPDV also caused mitochondrial damage by inducing mitochondrial fragmentation, depolarization, and powerless ATP production. Taken together, we show that HA possesses significant prebiotic and anti-fatigue effects in C57BL/6 mice.
... HA conjugation with different drugs such as paclitaxel, 5-fluro uracil, doxorubicin and methotrexate has been well-documented in previous literature [26][27][28][29] with drug liberation by the intracellular cleavage of HA-drug bonds [30]. In addition, HA by its antioxidant potential would decrease oxidation response, preventing hepatic stellate cells activation and decreasing the possibility of liver fibrosis [31,32]. ...
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Drug covalently bound to polymers had formed, lately, platforms with great promise in drug delivery. These drug polymer conjugates (DPC) boosted drug loading and controlled medicine release with targeting ability. Herein, the ability of entecavir (E) conjugated to hyaluronic acid (HA) forming the core of vitamin E coated lipid nanohybrids (EE-HA LPH), to target Kupffer cells and hepatocyte had been proved. The drug was associated to HA with efficiency of 93.48 ± 3.14 % and nanohybrids loading of 22.02 ± 2.3 %. DiI labelled lipidic nanohybrids improved the macrophage uptake in J774 cells with a 21 day hepatocytes retention post intramuscular injection. Finally, in vivo biocompatibility and safety with respect to body weight, organs indices and histopathological alterations were demonstrated. Coating with vitamin E and conjugation of E to HA (a CD44 ligand), could give grounds for prospective application for vectored nano-platform in hepatitis B.
... 8,15 In addition, recent studies have proven that HA has antioxidant properties (in vivo and vitro), inhibiting lipid peroxidation and reducing the activity of ROS by scavenging ROS free radicals. 18 In-tube screening of the product, containing pure vitamin C (10% L-ascorbic acid, at pH = 2.8), revealed a strong antioxidant potential and a high efficacy against lipid peroxidation and protein glycosylation. The protective effect of the formula against RMSinduced damage was validated in human keratinocyte cultures. ...
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Objective: To assess the in vitro efficacy on antioxidant potential, protection against global oxidative stress, and effect on collagen neosynthesis of minimalist formula (Peptide-C ampoules product) containing 10% natural vitamin C, rice and lupin bio-peptides, hyaluronic acid, and Vichy volcanic mineralizing water (active mix). Methods: In-tube quantitative tests ("in-tube screening") assessed global antioxidant properties, anti-lipid peroxidation, anti-protein glycosylation, and metalloproteinase inhibition (anti-collagenase, anti-elastase, and anti-hyaluronidase activity) properties of the formula. Protection against oxidative stress was evaluated on human keratinocyte monolayer cultures, and collagen neosynthesis was quantified on fibroblast monolayer cultures treated with supernatants from product-treated reconstructed human epidermis. Results: Product (5% concentration) showed high antioxidant ability (blocking 99.0% oxidation), protection against oxidative stress damage (51.8% lipid peroxidation and 37.8% protein glycosylation decreases), and inhibition of hyaluronidase (21.9%), elastase (47.1%), and collagenase (61.8%). The protective effect was validated on human keratinocyte monolayer cultures in the presence of active mix (0.025%). Oxidative stress (ROS) was reduced by 99.0%, while global oxidative stress (RMS) induced by pollution, UVA radiation, and a combination of both factors was reduced by 48.94%, 8.7%, and 96.28%, respectively. The product increased collagen neosynthesis (11.21%) by cellular dialogue in fibroblasts incubated with product/mix-treated-RHE supernatants. Conclusion: The combination of ingredients in the product showed high global antioxidant capacity, as well as a protective effect against oxidative stress induced by UVA, pollution, or both combined factors and an ability to stimulate collagen neosynthesis in in vitro studies, which support the clinical efficacy of this product.
... Hyaluronic acid has already been proved as an extremely interesting biomolecule with an array of effects, from signaling, space-occupying, lubricating joints, and trapping water inside various tissues to anti-inflammatory and regenerative effects; in the oral cavity, it has been found that it also displays anti-edematous, anti-bacterial, and pro-angiogenetic properties [42]. An investigation by Ke et al. [43] found that hyaluronic acid has pronounced free radical scavenging and antioxidant activities, while Bergandi et al. [44] proved that the loss of hyaluronic acid in the corpus vitreous was directly related to oxidative stress and lipid peroxidation. ...
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Periodontitis is a common oral disease affecting the tooth-supporting tissues. Bacteria have been long viewed as the main causative factor in its development; however, many investigations have proved that aberrant immune and inflammatory response and the resulting misbalance between the damage caused by reactive oxygen species and the antioxidant capacity of tissues may be an underlying factor in disease progression that reduces healing potential. The objective of the current trial is to assess the outcomes of the addition of hyaluronic acid (HA) to standard non-surgical periodontal therapy (NST) on some major oxidative stress markers in saliva. HA-based gel designed for dental application was used and the measurements were taken after 3 months. HA adjunctive therapy had a significantly greater increase in markers with antioxidant properties as well as total antioxidant capacity compared to standard NST alone. Furthermore, clinically measured levels of gingival inflammation (bleeding on probing-BOP) and periodontal destruction (clinical attachment loss-CAL) were significantly correlated with these markers, and the correlation was negative. This investigation demonstrates that HA may indeed express antioxidant properties and improve the antioxidant capacity of periodontal tissues, thus improving the prognosis for the teeth and the results of periodontal therapy. Further investigations will be necessary to determine the duration of these effects over time.
... HA is also known to have antioxidant properties but the mechanism is also not clearly understood, even if we can consider that the available hydroxyl functions present on the backbone can have, as is the case for chitosan and its derivatives, a positive effect by trapping free radicals, such as ROS. It was demonstrated that the lowest molecular weight HAs had the highest antioxidant activity [56]. In crosslinked HA hydrogel, the crosslinking reaction induces a steric hindering; the functions of the polymer backbone known to participate in the capture of free radicals are therefore less accessible. ...
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Lubrication and free radical scavenging are key features of biomaterials used for viscosupplementation (VS) of joints affected by osteoarthritis (OA). The objective of this study was to describe the non-clinical performance characterization of KiOmedine® CM-Chitosan, a nonanimal carboxymethyl chitosan, in order to assess its intended action in VS and to compare it to existing viscosupplements based on crosslinked hyaluronan (HA) formulations. Conclusion. Overall, the results provide a first insight into the mechanism of action in terms of lubrication and free radical scavenging for the use of KiOmedine® CM-Chitosan as a VS treatment of OA. KiOmedine® CM-Chitosan demonstrated a higher capacity to scavenge free radicals, and it showed a higher recovery of mobility after a knee lesion than crosslinked HA formulations. This difference could be explained by the difference in chemical structure between KiOmedine® CM-Chitosan and HA and their formulations. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0256770
... In previous studies, much attention has been focused on the unique appearance of HA as an antioxidant in pharmaceutical products 69,70 . DPPH is a stable free radical that significantly its absorbance decreases when exposed to the radical scavengers. ...
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Hyaluronic acid (HA), a unique polysaccharide with excellent Physico-chemical properties, is broadly used in pharmaceutical, biomedical, and cosmetic fields. It is widely present in all vertebrates, certain bacterial strains, and even viruses while it is not found in plants, fungi, and insects. HA is naturally synthesized by a class of integral membrane proteins called Hyaluronic acid synthase (HAS). Thus far, industrial production of HA is carried out based on either extraction from animal sources or large-scale microbial fermentation. The major drawbacks to using these systems are contamination with pathogens and microbial toxins. Recently, the production of HA through recombinant systems has received considerable attention. Plants are eco-friendly ideal expression systems for biopharmaceuticals production. In this study, the optimized human hyaluronic acid synthase2 ( hHAS2 ) sequence was transformed into Nicotiana tabacum using Agrobacterium rhizogenes . The highest rhHAS2 concentration of 65.72 ng/kg (wet weight) in transgenic tobacco hairy roots was measured by the human HAS2 ELISA kit. The HA production in the transgenic hairy roots was verified by scanning electron microscope (SEM) and quantified by the HA ELISA kit. The DPPH radical scavenging activity of HA with the highest concentration of 0.56 g/kg (wet weight) showed a maximum activity of 46%. Gel Permeation Chromatography (GPC) analyses revealed the high molecular weight HA (HMW-HA) with about > 0.8 MDa.
... To counteract the damage caused by ROS, cells possess an antioxidant defense system which can be distinguished by enzymatic and nonenzymatic antioxidants [10]. For example, the glycosaminoglycan hyaluronic acid (HA), which is one of the main components of the brain extracellular matrix, was described to have a great antioxidant activity [26] as well as anti-inflammatory properties [27]. Human serum albumin (HSA), which accounts for 55% of proteins present in the human plasma proteome and therefore is the most abundant protein in human plasma, further possesses a high anti-oxidative activity [28]. ...
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Neuroprotection from oxidative stress is critical during neuronal development and maintenance but also plays a major role in the pathogenesis and potential treatment of various neurological disorders and neurodegenerative diseases. Emerging evidence in the murine system suggests neuroprotective effects of blood plasma on the aged or diseased brain. However, little is known about plasma-mediated effects on human neurons. In the present study, we demonstrate the neuroprotective effect mediated by human plasma and the most abundant plasma–protein human serum albumin against oxidative stress in glutamatergic neurons differentiated from human neural crest-derived inferior turbinate stem cells. We observed a strong neuroprotective effect of human plasma and human serum albumin against oxidative stress-induced neuronal death on the single cell level, similar to the one mediated by tumor necrosis factor alpha. Moreover, we detected neuroprotection of plasma and human serum albumin against kainic acid-induced excitatory stress in ex vivo cultured mouse hippocampal tissue slices. The present study provides deeper insights into plasma-mediated neuroprotection ultimately resulting in the development of novel therapies for a variety of neurological and, in particular, neurodegenerative diseases.
... Interestingly, although the expressions of DHE and 4-HNE in the Blank-MNs group were similar to those in the model group, a significantly lower MDA level was observed in the Blank-MNs group than that in the model group, perhaps owing to the moderate lipid peroxidation inhibiting effect of HA with low molecular weight. 48,49 Altogether, these findings suggested that the Ce-MNs system was able to potently reshape the perifollicular oxidative microenvironment in the alopecia area. ...
... Compared to pure LF, the antioxidant activities of the LF-HA complexes and conjugates were significantly (p < 0.05) higher (Fig. 5d). Previous studies have reported that HA possesses free radical scavenging and antioxidant activities (Ke, Sun, Qiao, Wang, & Zeng, 2011;Wu, 2012). Although the addition of HA to the LF led to a significant increase in DPPH scavenging activity, the HA alone did not exhibit strong antioxidant activity. ...
Article
The molecular characteristics and functional properties of lactoferrin (LF)-hyaluronic acid (HA) mixtures and conjugates formed by physical mixing and chemical conjugation were compared. LF and HA interactions were characterized using phase behavior, particle size, zeta-potential and isothermal titration calorimetry (ITC) analysis. The physicochemical and functional properties of the LF-HA mixtures and conjugates were also measured, including their foaming, emulsifying, and antioxidant capacities. LF and HA formed molecular complexes over a wide range of pH values, resulting in changes in particle size, charge and structure. The net charge and thermal stability of the proteins in the LF-HA mixtures and conjugates were higher than that of free proteins. Covalently attaching HA to LF significantly (p < 0.05) improved its emulsifying capacity, with the highest emulsifying activity index (47.7 ± 0.1 m²/g) and emulsion stability index (83.2 ± 0.4 min) being obtained, but it did not improve its foaming properties. The antioxidant capacity of LF in mixtures and conjugates was increased by around 9% and 10%, respectively. This study showed that the functional performance of LF could be enhanced by forming complexes or conjugates with HA, which may extend its use in a variety of food applications.
... The antioxidant potential of HA produced by transgenic hairy roots was measured regarding their e ciency in scavenging free radicals generated by DPPH. Results revealed that the isolated HA with a concentration of 0.56 g/kg (wet weight) exhibited an acceptable level of antioxidant activity of 46%, which implies its possible application in pharmaceutical products 45,46 . ...
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Hyaluronic acid (HA), a unique polysaccharide with excellent physicochemical properties, is broadly used in pharmaceutical, biomedical, and cosmetic fields. It is widely present in all vertebrates, certain bacterial strains, and even viruses while it is not found in plants, fungi, and insects. HA is naturally synthesized by a class of integral membrane proteins called Hyaluronic acid synthase (HAS). Thus far, industrial production of HA is carried out based on either extraction from animal sources or large-scale microbial fermentation. The major drawbacks to using these systems are contamination with pathogens and microbial toxins. Recently, the production of HA through recombinant systems has received considerable attention. Plants are eco-friendly ideal expression systems for biopharmaceuticals production. In this research, the optimized human hyaluronic acid synthase2 (hHAS2) sequence was transformed into Nicotiana tabacum using Agrobacterium rhizogenes. The highest hHAS2 production in the tobacco hairy roots was 65.72 ng/kg (wet weight). The extracted HA was verified and quantified by the HA ELISA kit. The DPPH radical scavenging activity of HA with the highest concentration of 0.56 g/kg (wet weight) showed the maximum activity of 46%. Gel Permeation Chromatography (GPC) analyses revealed the high molecular weight HA with about > 0.8 MDa.
... One way to do this is to remove hydroxyl radicals directly. Hydrogen atoms in the HA molecular chain can combine with hydroxyl radicals to form water molecules to scavenge ROS [111,112]. It was found that the infrastructure unit of HA did not change before and after degradation, so the change of molecular weight may not affect the binding of hydrogen and hydroxyl radicals on the molecular chain of HA. ...
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Although the mortality rate of patients suffering from spinal cord injury (SCI) has decreased as the modalities of clinical therapy have been improved, the recovery of motor and sensory functions remains a challenge, ultimately leading to paraplegia or quadriplegia. Recently, neural tissue engineering scaffolds with appropriate physical and biological functions have been extensively developed to promote nerve regeneration and improve motor and sensory functions during SCI therapy. In this work, we summarized the physical support and bioelectrical signal conduction of polymer scaffolds for SCI repair from the aspects of biocompatibility, biodegradation, internal structure, mechanical performance, and conductivity. In addition, the biological functions of the polymer scaffolds were reviewed for the reversal of adverse pathophysiological factors to regulate the microenvironment of the injured site and promote endogenous neurogenesis during SCI therapy. Moreover, the future development of these engineered scaffolds for potential clinical applications was predicted.
... Besides its clinical applications, hyaluronic acid is also known to display in vitro and in vivo antioxidant activity. Ke et al. (2011) demonstrated that low-molecular-weight hyaluronic acid produced from its high-molecular-weight counterpart was able to effectively inhibit lipid peroxidation and scavenge superoxide anion, hydroxyl, and 1,1-diphenyl-2-picryldydrazyl (DPPH) radicals. When administered orally to immunosuppressed mice, hyaluronic acid increased the activity of endogenous antioxidant enzymes, namely superoxide dismutase, catalase, and glutathione peroxidase. ...
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The approval of new ingredients and compounds for use in food supplements is subjected to governmental regulations in many countries. In this context, there is a gap between what the scientific literature reports and how these translate into food regulation when it comes to bioactives. In this perspective piece, we analyze the case of Anvisa’s Normative Instruction (NI) N° 76, which regulates food supplements in Brazil. This updated version of a previous Normative Instruction adds hyaluronic acid, boron, silicon, undenatured type II collagen, hydroxymethylbutyrate, methylsulfonylmethane, and palmitoylethanolamide to its list of approved compounds. According to the NI, only supplements containing undenatured type II collagen are allowed to make health claims on their labels. In addition, the list does not include any substance from major bioactive groups, such as phenolic compounds. However, this might be due to the fact that the metabolic fate of phenolics has not yet been completely clarified, which could contribute to the slowing down of their approval by Anvisa. In this case, safety issues would need to be sorted out, and a direct relationship between consumption and health effect would need to be established for allowing health claims to be made. Therefore, the need for studies on the bioefficacy of bioactive compounds is imperative.
... Among cell damages caused by toxic Cd 2 + ions (major concerns in medical applications), the toxicity of CdSe/ZnS at a dose of 40 mg/kg has been reported in mice, followed by a reduction in the number of spermatogonia, spermatocytes, and spermatids. Moreover, colloidal QDs, such as ZnS, CdS, ZnSe, CdTe, and PbSe, which can diffuse from ultraviolet to infrared light, have been produced [24]. ...
Article
Background: Nanoparticles (NPs) are a group of particles with at least one dimension ranging from 1 nm to 100 nm in diameter and a surrounding interfacial layer. The NP-protein interactions include covalent and non-covalent bonds. Several dehydrogenase enzymes (e.g., alcohol dehydrogenase, lactate dehydrogenase, alanine dehydrogenase, glutamate dehydrogenase, leucine dehydrogenase, phenylalanine dehydrogenase, and malate dehydrogenase) are used for immobilization by NPs. Also, magnetic NPs and quantum dots are promising model systems for the design of bioanalytical sensors and biological enzyme assemblies. In this overview, we aimed to improve the current knowledge of interactions between dehydrogenase enzymes and NPs and to introduce dehydrogenases with industrial and medical applications. Also, bioconjugation of NPs with dehydrogenase enzymes has broad applications in biocatalysis and nanomedicine in the field of drug discovery. However, studies on the characterization of NP-enzyme complexes show that the anatomy and activity of enzymes are dependent on the chemistry of NP ligands, NP size, and labeling methods. Moreover, the NPprotein conjugates show increased/decreased enzymatic activities, depending on the NP features. Conclusion: In this study, we reviewed the findings related to NP-enzyme interactions for nanotechnology applications and conjugation techniques. We also highlighted several challenges associated with the NP-enzyme interactions, including the stability and reusability of enzymes in NP-enzyme formation.
... Oxidative damage protection provided by antioxidant and repair systems are typically insufficient. Because of that, too much attention has been focused on the role of hyaluronic acid as an antioxidant [6,19,23,25]. ...
... All the samples were able to preserve the antioxidant capacity of the precursor, naringenin, and, in particular, the most potent activity was exhibited by the ester, empty SLNs and HA-Poloxamer 407 based formulation; these last results can be attributable to the presence of hyaluronic acid that is also known to exert an antioxidant activity [47]. ...
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Psoriasis is one of the most common human skin disorders. Although its pathogenesis is complex and not completely know, the hyperactivation of the immune system seem to have a key role. In this regard, among the most effective systemic therapeutics used in psoriasis, we find cyclosporine, an immunosuppressive medication. However, one of the major problems associated with the use of cyclosporine is the occurrence of systemic side effects such as nephrotoxicity, hypertension, etc. The present work fits in this context and its aim is the design of suitable platforms for cyclosporine topical release in psoriasis treatment. The main objective is to achieve local administration of cyclosporine in order to reduce its systemic absorption and, consequently, its side effects. In order to improve dermal penetration, solid lipid nanoparticles (SLNs) are used as carriers, due to their lipophilicity and occlusive properties, and naringenin and linolenic acid are chosen, due to their properties, as starting materials for SLNs design. In order to have dermatological formulations and further modulate drug release, SLNs are incorporated in several topical vehicles obtaining gels with different degree of lipophilicity. Potential applications for psoriasis treatment were evaluated by considering the encapsulation efficiency, release profiles, in vitro skin permeation, and anti-inflammatory effects.
... The appropriate balance between synthesis and degradation of HA is vital in the regulation of various biological functions including cell proliferation, migration, differentiation (Bychkov and Kuzmina, 2015), vasculogenesis and angiogenesis (Pardue et al., 2008), as well as regulating cell adhesion and motility (Kouvidi et al., 2011), as determined by their molecular weight. LMW-HA on the other hand exerts opposite effect as compared to HMW-HA where it demonstrates biological activities such as antioxidant properties and pronounced free radical scavenging has been developed in recent years (Ke et al., 2011). In addition, LMW-HA has also shown to induce inflammatory genes in T-24 carcinoma cells, in eosinophils (Ohkawara et al., 2000) as well as dendritic cells (Termeer et al., 2000). ...
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Hyaluronic acid (HA), a major component of extracellular matrix has been widely applied in pharmaceutical and cosmetic industries due to its reported pharmacological properties. Various types of HA drug delivery system including nanoparticles, cryogel-based formulations, microneedle patches, and nano-emulsions were developed. There are studies reporting that several HA-based transdermal delivery systems exhibit excellent biocompatibility, enhanced permeability and efficient localized release of anti-psoriasis drugs and have shown to inhibit psoriasis-associated skin inflammation. Similarly HA is found in abundant at epidermis of atopic dermatitis (AD) suggesting its role in atopic AD pathology. Anti-allergenic effect of atopic eczema can be achieved through the inhibition of CD44 and protein kinase C alpha (PKCα) interaction by HA. Herein, we aim to evaluate the current innovation on HA drug delivery system and the other potential applications of HA in inflammatory skin diseases, focusing on atopic dermatitis and psoriasis. HA is typically integrated into different delivery systems including nanoparticles, liposomes, ethosomes and microneedle patches in supporting drug penetration through the stratum corneum layer of the skin. For instance, ethosomes and microneedle delivery system such as curcumin-loaded HA-modified ethosomes were developed to enhance skin retention and delivery of curcumin to CD44-expressing psoriatic cells whereas methotrexate-loaded HA-based microneedle was shown to enhance skin penetration of methotrexate to alleviate psoriasis-like skin inflammation. HA-based nanoparticles and pluronic F-127 based dual responsive (pH/temperature) hydrogels had been described to enhance drug permeation through and into the intact skin for AD treatment.
... However, with a molecular weight of around 2000 kDa, nature HA has a high viscosity and is hence not easily injected into the human body through the blood vessels. Accordingly, several groups have investigated the physiological functions of low molecular weight hyaluronic acid (LMWHA) (80-800 kDa) [15,16]. It was reported that LMWHA exhibits a potentially beneficial effect on wound healing immune response and angiogenesis [17]. ...
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Low-molecular-weight hyaluronic acid (LMWHA) was integrated with superparamagnetic Fe3O4 nanoparticles (Fe3O4 NPs). The size distribution, zeta potential, viscosity, thermogravimetric and paramagnetic properties of the LMWHA-Fe3O4 NPs were systematically examined. For cellular experiments, MCF7 breast cancer cell line was carried out. In addition, the cell targeting ability and characteristics of the LMWHA-Fe3O4 NPs for MCF7 breast cancer cells were analyzed using the thiocyanate method and time-of-flight secondary ion mass spectrometry (TOF-SIMS). The experimental results showed that the LMWHA-Fe3O4 NPs were not only easily injectable due to their low viscosity, but also exhibited a significant superparamagnetic property. Furthermore, the in vitro assay results showed that the NPs had negligible cytotoxicity and exhibited a good cancer cell targeting ability. Overall, the results therefore suggest that the LMWHA-Fe3O4 NPs have considerable potential as an injectable agent for enhanced magnetic resonance imaging (MRI) and/or hyperthermia treatment in breast cancer therapy.
... As shown in Figure 12B, both synthesized hydrogels were not harming the integrity of the plasma membrane. The antioxidant activity of HA is observed in some studies [6,42]. Here the issue of whether Gel-25 or Gel-37 can affect the intracellular ROS content of the treated cells was investigated in comparison with a commercial hydrogel, Perfectha. ...
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Hyaluronic acid (HA), as a safe biomaterial with minimal immunogenicity, is being employed in a broad range of medical applications. Since unmodified HA has a high potential for biodegradation in the physiological condition, herein, an HA-based cross-linked hydrogel was formulated using polydimethylsiloxane-diglycidyl ether terminated (PDMS-DG) via epoxide-OH reaction. The formation of HA-PDMS hydrogel was confirmed using FTIR, NMR, and FESEM. Temperature demonstrated a critical role in the physicochemical properties of the final products. Gel-37, which formed at 37 °C, had a higher modification degree (MD) and more stability against hyaluronidase and oxidative stress than the hydrogel formulated at 25 °C (Gel-25). In addition, the swelling ratio, roughness, and porous network topology of Gel-25 and Gel-37 were different. The rheology measurement indicated that HA-PDMS hydrogel had a stable viscoelastic character. The hydrogel was also biocompatible, non-cytotoxic, and considerably stable during 7-months storage. Overall, various determined parameters confirmed that HA-PDMS hydrogel is worth using in different medical applications. Keywords: Hyaluronic acid; Polydimethylsiloxane-diglycidyl ether terminated; Hydrogels; Long-term stability; Viscoelastic behavior; Biocompatibility.
... In our study, we use highly purified CNTs with very low amounts of Fe (65 ppm) or Al (10 ppm), so when incubated with the cells they do not cause an increase in ROS, and only a slight increase in the case of ox-CNTs-HA-CPT in TC-1 cells and this effect can be attributed to the drug [39]. On the other hand, we observe that the ROS levels of the fibroblasts were reduced when treated with the CNTs, this may be possible because the CNTs have a great electronic affinity on their molecular orbitals of the carbon atoms of their graphene walls, acting as a free radical scavenger [40,41], in addition, we observe that this effect is enhanced by the addition of hyaluronic acid, since it has antioxidant activity as well [42]. The preliminary results of present study show that ox-CNTs-HA-CPT have a good and specific antitumor effect in vitro; however, further studies should be carried out to determine the cell death pathways involved, the amount of CPT in the nanovector, as well as its application in an in vivo tumor model, in order to know the effects of the nanovector in a broader sense. ...
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Carbon nanotubes (CNTs) have emerged in recent years as a potential option for drug delivery, due to their high functionalization capacity. Biocompatibility and selectivity using tissue-specific biomolecules can optimize the specificity, pharmacokinetics and stability of the drug. In this study, we design, develop and characterize a drug nanovector (oxCNTs-HA-CPT) conjugating oxidated multi-wall carbon nanotubes (oxCNTs) with hyaluronate (HA) and carboplatin (CPT) as a treatment in a lung cancer model in vitro. Subsequently, we exposed TC–1 and NIH/3T3 cell lines to the nanovectors and measured cell uptake, cell viability, and oxidative stress induction. The characterization of oxCNTs-HA-CPT reveals that on their surface, they have HA. On the other hand, oxCNTs-HA-CPT were endocytosed in greater proportion by tumor cells than by fibroblasts, and likewise, the cytotoxic effect was significantly higher in tumor cells. These results show the therapeutic potential that nanovectors possess; however, future studies should be carried out to determine the death pathways involved, as well as their effect on in vivo models.
... Chemical and physical properties, such as solubility in water and solution viscosity greatly depend on the molecular weights of HA and NaHA [1]. Biochemical functions of low molecular weight HA (HA fragments) also differ from the native high molecular weight HA [1][2][3][4][5][6][7][8]. Therefore, the production of low molecular weight HA and NaHA are important for future advanced applications such as drug delivery methods and regenerative medicines [1,9]. ...
Article
In this work, reduction of the polysaccharide biopolymer, sodium hyaluronate (NaHA), was obtained without added chemicals or catalysts using high temperature water (180 to 260) oC, fast-heating-rates (417 to 750) oC∙s-1 and short reaction times (< 18 s) in a flow reactor. Results show that hydrothermal treatment of NaHA with fast-heating-rates convert the substrate into low molecular weight oligomers with minimal byproduct formation. A kinetic model assuming random depolymerization provided data correlation and allowed estimation of molecular weight reductions. Mechanism of the molecular weight reduction seems to be related to initial disentanglement of NaHA random coils through convective (turbulent) mixing and shear that minimizes heterogenous decomposition. Evidence for the mechanism includes lack of significant furan byproducts (fast-heating), clear product solutions and model applicability. Fast-heating with high temperature water allows selective conversion of high molecular weight NaHA into low molecular weight HA fragments without chemical modification, catalysts or additives.
... Recently, many studies have investigated the association between the molecular weight of HA and its physiological functions [14,15]. In the initial stage of wound healing, high-molecular-weight HA (HMWHA) (~2000 kDa) accumulates in the extracellular matrix and binds to fibrinogen to form a clot. ...
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In this study, we prepared low-molecular-weight hyaluronic acid (LMWHA) powder by γ-irradiation. The chemical and physical properties of γ-irradiated LMWHA and the in vitro cellular growth experiments with γ-irradiated LMWHA were analyzed. Then, hyaluronic acid exposed to 20 kGy of γ-irradiation was used to fabricate a carboxymethyl cellulose (CMC)/LMWHA fabric for wound dressing. Our results showed that γ-irradiated LMWHA demonstrated a significant alteration in carbon–oxygen double bonding and can be detected using nuclear magnetic resonance and ultraviolet (UV)-visible (Vis) spectra. The γ-irradiated LMWHA exhibited strain rate-dependent Newton/non-Newton fluid biphasic viscosity. The viability of L929 skin fibroblasts improved upon co-culture with γ-irradiated LMWHA. In the in vivo animal experiments, skin wounds covered with dressings prepared by γ-irradiation revealed acceleration of wound healing after two days of healing. The results suggest that γ-irradiated LMWHA could be a potential source for the promotion of skin wound healing.
... HA is known as an anti-inflammatory and an antioxidant material. 38,39 A number of RCTs, systematic reviews, and meta-analyses have evaluated the effect of HA on chronic inflammation. 26,27,38 However, to the best of our knowledge, currently, there are no studies measuring collagen membrane degradation following its immersion in HA in a preclinical in vivo study. ...
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Aim To examine the in vitro biokinetics of hyaluronic acid (HA) from a collagen membrane (CM) and to evaluate the in vivo effect of immersion of the CM in HA solution on its degradation in streptozotocin (STZ)‐induced diabetes conditions in a rat calvaria subcutaneous model. Background CM degradation is accelerated in uncontrolled diabetic rats. Immersion of CM in HA has been suggested to decrease their resorption rate without interfering with their tissue integration and structural degradation. However, it is unknown to what extent CM degradation may be influenced by its immersion in HA solution under a condition mimicking a medically compromised situation with an increased inflammatory level such as diabetes. Materials and Methods CMs were soaked in cross‐linked HA. Protein adsorption and the HA release were quantified by ELISA. Diabetes was induced in sixteen rats, while 16 healthy rats served as control. CM was prepared and labeled prior to implantation with Biotin. Seventeen CM were immersed in HA and 17 CM in PBS. In each animal, one test or one control disk was implanted. In order to compare the collagen content, two similar non‐implanted CM were used as baseline. Fourteen days after surgery, thirty‐two animals were sacrificed. The entire calvaria including the skin above, was chemically fixed, decalcified, and embedded in paraffin. Five‐μm‐thick sections were analyzed histologically and histomorphometrically using H&E and avidin‐peroxidase staining. Results The in vitro results demonstrated that the CM adsorbed roughly 80% of the total HA content. After 10 days, 36.3% of the initial HA remained on the CM. The in vivo results demonstrated that diabetes significantly reduced the thickness of the CM, while HA had a significant effect on keeping the membrane thickness. HA increased the residual collagen content in the diabetic group (P < 0.0001) but no such effect was observed in the healthy group. Conclusion Immersion of CM in HA prior to the implantation delays membrane degradation in uncontrolled diabetic compared with normoglycemic rats.
... Based on our results, we cannot give a clear explanation how the HA can affect all observed parameters. Numerous studies have confirmed the effect of HA on the activity of these enzymes but in other cells and tissues and not in erythrocytes [75,76]. It was confirmed that HA can reduce cellular superoxide generation and its accumulation through Nrf2 regulation which can induce transcription of antioxidant enzymes such as SOD, GPx, CAT, and others [61]. ...
... Therefore, to reduce the oxidative stress in the synovial fluid during arthritis, it is important to improve the antioxidant capacity. At early stages of arthritis, oxidative stress can be reduced by intra-articular administration of substances having antioxidant capacity, such as vitamin C, vitamin E, astaxanthin, and low molecular weight hyaluronic acid [11,19,23]. ...
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Arthritis is thought to cause oxidative stress in synovial fluid in humans, but there have been few reports in horses. To evaluate oxidative stress in synovial fluid in horses, this study used 19 horses with unilateral fracture of the carpal joint bone. Synovial fluid was collected from the carpal joint on the fracture (arthritis group) and contralateral (control group) sides. Diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) were then measured, and the oxidative stress index (OSI) was calculated. d-ROMs and OSI of the arthritis group were significantly higher than the control group. BAP of the arthritis group was significantly lower than the control group. Thus, this study revealed that oxidative stress develops in the synovial fluid of horses during arthritis.
Article
Increasing studies focus on chondroitin sulfate (CS) degradation to improve its biological activity. The review mainly introduces the degradation methods of CS and their mechanisms. Studies have shown that different degradation methods can lead to different structures of low molecular weight chondroitin sulfate (LMCS). LMCS were prepared through β-elimination reaction, hydrolysis reaction, hydrogen abstraction reaction, and deamination reaction. The degradation of CS is affected by two aspects: the structure of CS (disaccharide composition and molecular weight) and the influence of degradation conditions (temperature, pH, degradation promoters, auxiliary conditions, and time). LMCS with different structures have different biological activities. In addition, degradation could also change CS's metabolism, such as absorption effects and gut microbiota. Thus, choosing the appropriate degradation method for CS development and utilization is very important.
Article
This work investigated the potential of amoxicillin-doped hyaluronic acid/fucoidan multifunctional coatings on medical grade stainless steel as biocompatible, osteointegration enhancing, antimicrobial, and bacterial biofilm inhibiting coatings for orthopedic implants. The coatings were prepared by layer-by-layer spin coating and confirmed by optical contact angle goniometry and infrared spectroscopy. Time-of-flight secondary ion mass spectrometry showed a homogeneous distribution of the individual layers. In contrast, thermal diffusivity, and thermal conductivity measurements by photothermal beam deflection spectrometry showed diffusion of the amoxicillin into the hyaluronic acid and fucoidan layers. In vitro release of amoxicillin showed complete release within one hour, as reflected by the formation of inhibition zones against Staphylococcus aureus and Escherichia coli. Synergistic effects were observed between the hyaluronic acid and amoxicillin in inhibiting S.Aureus biofilm, and between the fucoidan and amoxicillin in improving the antioxidant properties by an ABTS radical scavenging assay. Biocompatibility was determined with human osteoblasts, confirming the potential of such multifunctional coatings to enhance the bioactivity of steel-based orthop edic implants.
Article
Advanced technologies for producing high-quality low molecular weight hyaluronic acid (LMW-HA) are required from the perspective of cost-efficiency and biosafety. Here, we report a new LMW-HA production system from high molecular weight HA (HMW-HA) using vacuum ultraviolet TiO2 photocatalysis with an oxygen nanobubble system (VUV-TP-NB). The VUV-TP-NB treatment for 3 h resulted in a satisfactory LMW-HA (approximately 50 kDa measured by GPC) yield with a low endotoxin level. Further, there were no inherent structural changes in the LMW-HA during the oxidative degradation process. Compared with conventional acid and enzyme hydrolysis methods, VUV-TP-NB showed similar degradation degree with viscosity though reduced process time by at least 8-fold. In terms of endotoxin and antioxidant effects, degradation using VUV-TP-NB demonstrated the lowest endotoxin level (0.21 EU/mL) and highest radical scavenging activity. This nanobubble-based photocatalysis system can thus be used to produce biosafe LMW-HA cost-effectively for food, medical, and cosmetics applications.
Article
Rapid development of stimuli-responsive drug delivery systems (DDSs) for tumor therapy has raised increasing interest in recent decades, and many nanomedicines are prepared to achieve accurate or sustained drug release. However, the fabrication process for these nanomedicines has been far too intricate and their potential biosafety has not been fully understood, which has hampered their clinical translation. Challenges for developing DDSs remain on balancing the complexity of the fabrication process with their translational feasibility. Owing to water-solubility, biocompatibility, biodegradability and CD44-targetability, hyaluronic acid (HA) as a versatile building block has gained great popularity due to a simplified fabrication process and unique characteristics of HA for DDSs. In this review, we overviewed the biological function and multiple chemical modifications of HA, and discussed the fabrication of HA-based drug delivery systems (HA-DDSs) with specific tumor microenvironmental stimuli-responsive linkers. We systemically surveyed the applications of HA-DDSs for chemotherapy, photothermal therapy, photodynamic therapy, immunotherapy, gene delivery and combination therapy.
Article
This research work was devoted to studying the ability of hyaluronic acid (HA) to treat skin wounds in rats. HA, an immune-neutral polysaccharide, is widespread in the human body as it is necessary for several tissues and cellular functions and has been used in the clinical practice for more than three decades. For this purpose, we attempted to obtain and enrich HA-containing extracts from two species of molluscs collected at Bizerte lagoon, namely Mytilus galloprovincialis and Crassostrea gigas. Then, the wound healing potential of purified HA (hyaluronan) was tested on Wistar rats which were separated into 4 groups: control, treated with a marketed healing cream “Avene Cicalfate”, treated with HA isolated from M. galloprovincialis, and treated with HA isolated from C. gigas. After anesthesia, rats were submitted to back skin lesions (diameter 2 cm) and then treated daily until recovery. During the experiment, variation of the wound area was monitored. Results showed that the obtained net yield of HA was 3.8 mg/g dry weight and 1.9 mg/g dry weight for M. galloprovincialis and C. gigas respectively. Morphological analysis demonstrated that HA significantly accelerated wound repair through reepithelization. The mean wound surface was completely absent after 15 days of treatment with C. gigas hyaluronan. Based on these findings, it appears that mollusc HA has an obvious healing activity completely in accordance with its recognized effectiveness in dermo-cosmetology.
Article
Hyaluronan (HA) possesses radical scavenging properties. The low molecular weight HA (LHA)-containing drink (PL) is a dietary supplement that consists of several antioxidants in addition to LHA. The aim of this study is to characterize the hydroxyl radical scavenging activity of LHA through the interactions between the components of PL in in vitro assays. Moreover, the efficacy of LHA toward oxidative stresses (ultraviolet C irradiation, oxidative DNA damage) was evaluated. LHA revealed the following hydroxyl radical-scavenging properties: 1) LHA directly scavenges hydroxyl radicals, 2) LHA activity is enhanced in the presence of other PL components, thereby enabling protection against oxidative damage to DNA, and 3) exposure to UVC-radiation temporarily attenuated the antioxidant activity of PL, which is recovered in an LHA-dependent process. These results suggest that LHA is an excellent material because its antioxidative activity is enhanced in the presence of other antioxidants, which ultimately increases resistance to oxidative stress.
Article
Objective: Shoulder tendinopathy is a prevalent and debilitating problem. We compared the effects of subacromial high- or low-molecular-weight hyaluronate injection with physical therapy (PT) in shoulder tendinopathy. Design: A triple-blinded randomized controlled trial. Setting: We conducted the trial in an outpatient clinic at a teaching hospital. Participants: In total, 79 patients with shoulder tendinopathy were randomly allocated to high- (n = 27) or low-molecular-weight (n = 28) hyaluronate or PT (n = 24) groups. Interventions: We administered a 20-mg injection of high- or low-molecular-weight hyaluronate. For PT, we prescribed 10 sessions of physiotherapy and exercise. Outcome measures: The primary outcome was shoulder pain and the secondary outcomes included Disability of the Arm Shoulder and Hand score, shoulder range of movement and QoL. We measured the outcomes at baseline, 1, and 3 months of treatment, and assessed shoulder pain at the sixth month postintervention. Results: The interventions were all clinically beneficial in the management of tendinopathy for high- (n = 25) and low-molecular-weight (n = 24) hyaluronate and PT (n = 19) groups (all P < 0.05). However, between-group analyses indicated that hyaluronate preparations were more effective in controlling pain, decreasing disability, increasing range of motion, and improving the quality of life (all P < 0.05). The pain and subjective feeling of rigidity at the injection area (P = 0.012) were less prominent for low-molecular-weight hyaluronate. Conclusion: High- or low-molecular-weight hyaluronate is more effective than PT in the treatment of shoulder tendinopathy. The clinical benefits of hyaluronate last for at least 3 months, and the pain alleviation sustains partially for 6 months. Shoulder injection of low-molecular-weight hyaluronate is more tolerable to the patient than high-molecular-weight hyaluronate.
Article
Chronic wounds deeply invalidate patient's quality of life, involving very high costs for the medical system. Numerous wound dressings have been studied over the years, and active wound dressings replaced traditional passive dressings to promote tissue regeneration and wound closure. Aiming at an optimal reproduction of the physiological environment, electrospun wound dressings are emerging since they mimic the architecture of the extracellular matrix and provide a large contact surface area, enabling exudate absorption and permeability as well as good conformability to the wound site. The use of polysaccharides offers an excellent biomimicry, as they ensure good biocompatibility, biodegradability, and non-immunogenicity. Furthermore, they possess bioactive properties, such as antimicrobial, anti-inflammatory, and antioxidant properties, which can promote and enhance the healing process. The aim of this review is to present the morphological, physical, and chemical features of an ideal wound dressing together with the traditional and the current strategies, and the already commercialized wound dressings. Moreover, the review is focused on the preparation of polysaccharide-based electrospun nanofibrous devices and on the strategies for the modulation and improvement of membrane stability and bioactivity. Lastly, a comprehensive consideration on the process and requirements that lead to the commercialization of the wound dressings is reported.
Article
Introduction: The tendons of the rotator cuff are major sources of shoulder pain. This study aimed to compare the effects of low molecular-weight hyaluronic acid with physiotherapy (PT) in patients with supraspinatus tendinopathy (ST). Methods: We carried out a parallel two-group randomized comparative clinical trial in an outpatient clinic of physical medicine and rehabilitation at a teaching hospital. In total, 51 patients (31 women) aged 20 to 55 years with ST were randomly allocated to subacromial hyaluronate injection (n = 28) and PT (n = 23) groups. For the hyaluronate group, we administered a single injection of 2 mL (20 mg) hyaluronate 1% (500 to 700 kDa). For PT, we prescribed three sessions of treatment per week for 12 weeks, totaling 36 sessions including rotator cuff activation exercises. The primary outcome was shoulder pain in the visual analog scale. The secondary outcomes included the range of movement and the disability score of the shoulder, and a World Health Organization questionnaire on quality of life. We did the measurements at the baseline and at one, four, and 12 weeks after intervention. Results: The results showed that both interventions were beneficial in the management of ST. However, hyaluronate was more effective in reducing shoulder pain at rest and during activities (both P < 0.001, effect size = 0.52 and 0.68, respectively). The two interventions similarly decreased patients' disability (P = 0.196). Hyaluronate improved shoulder motion and the quality of life better than PT. Conclusion: In the treatment of ST, low molecular-weight hyaluronate is more effective than PT, at least for three months. Particularly, hyaluronate is more successful in alleviating pain.
Article
Background: Shoulder pain most commonly originates from the tendon structures of the rotator cuff. Objective: We compared the clinical effects of high- versus low-molecular-weight (LMW) hyaluronic acid for the management of rotator cuff tendinopathy. Methods: We carried out a parallel, triple-blind, randomized comparative trial at a teaching hospital. In total, 56 patients aged 16 to 70 years with rotator cuff tendinopathy were randomly allocated to 2 groups. We administered a single shoulder injection of either 1 mL of 1% high- (>2000 kDa) or 1 mL of 1% LMW hyaluronate (500-700 kDa) to the corresponding groups. The primary outcome was the intensity of shoulder pain. The secondary outcomes were range of motion and disability of the shoulder, and quality of life. We performed the measurements at baseline and at 1, 4, and 12 weeks postintervention. The pain measurements were repeated at the sixth month postintervention. Results: Comparisons of baseline versus 3 months showed that both interventions were beneficial in the management of the tendinopathy (all P values <0.05). However, between-group analyses did not indicate any clinically significant difference between the 2 medications. The pain, induration (P = 0.007), and inflammation at the site of the injection were less prominent for LMW hyaluronate. Conclusion and relevance: Both medications are effective for the treatment of tendinopathy. The benefits last at least for 3 months, and pain alleviation lasts partially for 6 months. The shoulder injection of LMW hyaluronate is more tolerable to the patient. Therefore, we recommend LMW hyaluronate as the first choice for the management of rotator cuff tendinopathy.
Article
Reactive oxygen and nitrogen species (RONS) play a key role in physiological conditions as signaling molecules for regulating homeostasis in the human body. However, abnormally increased RONS levels can damage DNA, protein, and tissue, or even impair cellular signaling. Consequently, when this state is present for a long time, it can lead to severe inflammatory disorders, such as lupus, diabetes, rheumatoid arthritis, Crohn's disease, and neurodegenerative disorders. Although antioxidant therapies have been developed for a long time to treat acute or chronic inflammatory diseases, small molecule‐based antioxidants showed relatively low therapeutic effects due to rapid clearance and low stability in the bloodstream. As one of the solutions to overcome such limitations, incorporating polymers would provide enhanced blood stability, bioavailability, and even enhanced therapeutic effects. Herein, diverse polymeric antioxidant materials are introduced that are categorized into simple loading strategies and polymers with inherent antioxidative activity. Further, preclinical and clinical studies of polymeric antioxidant materials for anti‐inflammatory therapy are discussed and a better direction is provided for these to be pursued and improved in anti‐inflammatory therapy.
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Chapter
Hyaluronic acid (HA) plays an important role promoting the wound contraction increase and epidermal proliferation, cytokines regulation and adhesion molecules, collagen deposition increase, and neovascularization stimulus. Its function is associated with the molecular weight and its rheological properties. HA changes in the skin can be observed due to aging, wound healing, and degenerative disease. Traditionally, the native HA was extracted from animal tissues, but nowadays it is mainly produced by microbial fermentation. Microbial HA is recommended for human therapeutic products for medical, pharmaceutical, and cosmetic application because this one does not present risk of cross-species viral and other adventitious agent infection. In clinical medicine, HA and its derivatives have showed great potential in treatment of different types of wounds as burns. This chapter describes the HA properties, microbial polymer production, its function in the wound stages, and discusses the current trends of its utilization on wound healing treatment either as component of topical formulations or as scaffold.
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Bridging critical‐sized defects in peripheral nerves to achieve functional recovery is a challenge for orthopedic and hand surgeons. Inadequate regeneration of peripheral nerve axons often results in long‐term partial or total sensory and/or motor impairment. Currently, the best treatment available for long‐gap peripheral nerve regeneration is autologous nerve transplantation, while the successful implementation of this approach requires for secondary surgery and donor nerves. The nerve guide conduit (NGC) serves as an alternative to autograft of nerve, as it connects the proximal and distal ends of nerve defects and provides physical and biochemical guidances for axon regeneration. Functionalized NGCs enhance nerve regeneration by providing neuroprotection, antioxidation, vascular regeneration enhancement, and immune regulatory effects. In this review, the authors summarize the latest advances in functional polymer‐based NGCs for peripheral nerve regeneration and present the perspectives on the development of peripheral NGCs for potential clinical applications. Functional polymer‐based nerve guide conduits connect the proximal and distal ends of nerve defects and provide physical and biochemical guidance for axon regeneration, which enhances nerve regeneration by providing neuroprotection, antioxidation, angiogenesis, and immune regulation effects, indicating their great potential in clinical application.
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Analysis of UV-visible spectra, performed on commercial riboflavin-based eye drops, showed that absorbance is a saturating function of vitamin concentration. This implies a threshold concentration, Ct, such that for riboflavin concentration > Ct the absorbance remains constant and the effectiveness of the eye drops is independent of the dose used. These experimental results were combined with a diffusion–reaction model to elucidate the mechanism of action within the cornea. The model predicts that the eye drops have a low effectiveness on UVB and UVC, while they have a good performance for UVA. Indeed, at the center of the cornea the transmittance is significantly reduced and after 1 h it is reduced by about 70% compared to a cornea devoid of eye drops.
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The development of cancer in humans and animals is a multistep process. The complex series of cellular and molecular changes participating in cancer development are mediated by a diversity of endogenous and exogenous stimuli. One type of endogenous damage is that arising from intermediates of oxygen (dioxygen) reduction - oxygen-free radicals (OFR), which attacks not only the bases but also the deoxyribosyl backbone of DNA. Thanks to improvements in analytical techniques, a major achievement in the understanding of carcinogenesis in the past two decades has been the identification and quantification of various adducts of OFR with DNA. OFR are also known to attack other cellular components such as lipids, leaving behind reactive species that in turn can couple to DNA bases. Endogenous DNA lesions are genotoxic and induce mutations. The most extensively studied lesion is the formation of 8-OH-dG. This lesion is important because it is relatively easily formed and is mutagenic and therefore is a potential biomarker of carcinogenesis. Mutations that may arise from formation of 8-OH-dG involve GC --> TA transversions. In view of these findings, OFR are considered as an important class of carcinogens. The effect of OFR is balanced by the antioxidant action of non-enzymatic antioxidants as well as antioxidant enzymes. Non-enzymatic antioxidants involve vitamin C, vitamin E, carotenoids (CAR), selenium and others. However, under certain conditions, some antioxidants can also exhibit a pro-oxidant mechanism of action. For example, beta-carotene at high concentration and with increased partial pressure of dioxygen is known to behave as a pro-oxidant. Some concerns have also been raised over the potentially deleterious transition metal ion-mediated (iron, copper) pro-oxidant effect of vitamin C. Clinical studies mapping the effect of preventive antioxidants have shown surprisingly little or no effect on cancer incidence. The epidemiological trials together with in vitro experiments suggest that the optimal approach is to reduce endogenous and exogenous sources of oxidative stress, rather than increase intake of anti-oxidants. In this review, we highlight some major achievements in the study of DNA damage caused by OFR and the role in carcinogenesis played by oxidatively damaged DNA. The protective effect of antioxidants against free radicals is also discussed.
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Reactive oxygen species (ROS) are produced in many normal and abnormal processes in humans, including atheroma, asthma, joint diseases, aging, and cancer. The superoxide anion O(2)(-) is the main ROS. Increased ROS production leads to tissue damage associated with inflammation. Superoxide dismutases (SODs) convert superoxide to hydrogen peroxide, which is then removed by glutathione peroxidase or catalase. Thus, SODs prevent the formation of highly aggressive ROS, such as peroxynitrite or the hydroxyl radical. Experimental models involving SOD knockout or overexpression are beginning to shed light on the pathophysiological role of SOD in humans. Although the antiinflammatory effects of exogenous native SOD (orgotein) are modest, synthetic SOD mimetics hold considerable promise for modulating the inflammatory response. In this review, we discuss new knowledge about the role of the superoxide anion and its derivates as mediators of inflammation and the role of SODs and SOD mimetics as antioxidant treatments in joint diseases such as rheumatoid arthritis, osteoarthritis, and crystal-induced arthropathies.
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Hyaluronan is being used increasingly as a component of artificial matrices and in bioengineering for tissue scaffolding. The length of hyaluronan polymer chains is now recognized as informational, involving a wide variety of size-specific functions. Inadvertent scission of hyaluronan can occur during the process of preparation. On the other hand, certain size-specific hyaluronan fragments may be desirable, endowing the finished bioengineered product with specific properties. In this review, the vast arrays of reactions that cause scission of hyaluronan polymers is presented, including those on an enzymatic, free radical, and chemical basis.
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CD8 + T cells respond to antigen stimulation through a process of activation, division, and differentiation generating a large pool of activated effector cytolytic T lymphocytes (CTLs). Many cancer patients harbor the accordant precursor CTLs capable of responding to various tumor‐associated antigens (TAA). In selected cases, vaccination with these TAA can elicit detectable antitumor responses. Presently, the clinical outcome of cancer vaccination remains inadequate. The lack of clinical efficacy may be attributed to various molecular and cellular mechanisms developed by tumors to successfully evade the host immune system. Some of these mechanisms have been identified. It is becoming increasingly apparent that immunotherapy with the sole objective of inducing immune activation is in itself not sufficient to fully overcome the mechanisms averting efficient antitumor responses. Strategies to neutralize tumor‐induced immune suppression have to be developed in parallel to antigenic stimulation. Our data show that both oxidative stress‐ and antigen‐mediated preferential cell death of antigen‐experienced memory CTLs may be a major contributor to tumor‐induced immune dysfunction. The persistence of functional CTLs is a key element for an efficient antitumor response and affects the outcome of any immunotherapy protocol. We therefore propose that protecting CTLs from premature death by identifying and targeting the responsible pathway can lead to substantial enhancement in antitumor response. In this review, we discuss some of the fundamental factors that may be involved in the modulation of the different lymphocyte subsets towards sensitization or resistance to tumor‐induced stress.
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Hyaluronate lyase cleaves hyaluronan chains at a β-d-GalNAc-(1→4)-β-d-GlcA bond, ultimately breaking the polysaccharide down to 3-(4-deoxy-β-d-gluc-4-enuronosyl)-N-acetyl-d-glucosamine. In the present paper, the recombinant hyaluronate lyase (EC 4.2.2.1, HA lyase) of Streptococcus pyogenes bacteriophage H4489A was produced, purified and applied to digest hyaluronan producing unsaturated hyaluronan oligomers. The resulted unsaturated hyaluronan oligomers were purified and subjected to anion-exchange high performance chromatography. The cytotoxic activities of naturally hyaluronan, hyaluronate lyase and unsaturated hyaluronan oligomers were tested and evaluated against HEp-2 (human laryngeal carcinoma), Daoy (human medulloblastoma), MCF-7 (human breast adenocarcinoma), and WiDr (human colon adenocarcinoma) tumor cell lines. Also, their antioxidant activities have been examined by the inhibition of lipid oxidation and free radical scavenging assays.
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The antioxidant activities of crude Hyriopsis cumingii polysaccharides (HCPS) were evaluated both in vitro and in vivo. In vitro antioxidant assay, HCPS (crude and its purified fraction) could scavenge hydrogen peroxide, free radicals of superoxide anion and 2,2-diphenyl-1-picryl-hydrazyl, chelate ferrous ion and reduce ferric ion. Except for metal ion chelating activity, HCPS-3 exhibited much higher antioxidant activities than crude HCPS, HCPS-1 and HCPS-2. For antioxidant testing in vivo, different doses of crude HCPS were orally administrated over a period of 15 days in a d-galactose induced aged mice model. As results, administration of crude HCPS inhibited significantly the formation of malondialdehyde in mice livers and serums and raised the activities of antioxidant enzymes and total antioxidant capacity in a dose-dependent manner. The results suggested that HCPS had direct and potent antioxidant activities.
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Crude capsule polysaccharides (CCP) were prepared from the culture of Streptococcus equi subsp. zooepidemicus C55129 and were partially purified through an anion-exchange column chromatography to afford partially purified capsule polysaccharides (PCP). The main component of CCP and PCP was hyaluronic acid. In vitro antioxidant assay, the capsule polysaccharides showed strong inhibition of lipid peroxidation and hydroxyl radical scavenging activity and moderate 1,1-diphenyl-2-picryldydrazyl radical scavenging activity. In addition, CCP exhibited much stronger reductive power than PCP. For antioxidant testing in vivo, CCP and PCP were orally administrated over a period of 15 days in a d-galactose induced aged mice model. As results, administration of capsule polysaccharides inhibited significantly the formation of malondialdehyde in mice livers and serums and raised the activities of antioxidant enzymes and total antioxidant capacity in a dose-dependent manner. However, the antioxidant activity of CCP was lower than that of PCP. The results suggest that the capsule polysaccharides from Streptococcus equi subsp. zooepidemicus C55129 have direct and potent antioxidant activities.
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Hyaluronic acid (Hyaluronan, HA) was depolymerised by gamma irradiation and its structural changes and antioxidant activities were investigated. The structural changes of gamma irradiated HA were studied by gel-permeation chromatography (GPC), viscosity, pH, Hunter colour measurement, UV spectrophotometry, and FT-IR spectroscopy. The results demonstrated that gamma irradiation decreased molecular weight size, viscosity and pH of the hyaluronic acid and its colour turned to intense yellow. UV spectra of the irradiated HA showed a change at 265nm, which indicates the formation of double bonds. Differences in the height and shape of certain absorption bonds of FT-IR spectra in the range 1700-1750cm(-1) were also observed, which is associated with the formation of carboxylic acid. From these structural changes of the HA, gamma irradiation may have a role in the formation of pyrancarboxylic acid rings. DPPH radical scavenging ability and the reducing power of gamma irradiated HA were significantly higher than that of non-irradiated HA. However, non-irradiated and irradiated HA did not show significant differences in the Rancimat test. Copyright © 2008 Elsevier Ltd. All rights reserved.
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The effectiveness of mint leaves, a common herb used in Indian cuisine, as a natural antioxidant for radiation-processed lamb meat was investigated. Mint extract (ME) had good total phenolic and flavonoid contents. It exhibited excellent antioxidant activity, as measured by β-carotene bleaching and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. It also showed a high superoxide- and hydroxyl-scavenging activity but low iron-chelating ability. A positive correlation was found between the reducing power and the antioxidant activity. The antioxidant activity of ME was found to be comparable to the synthetic antioxidant, butylated hydroxytoluene (BHT). The suitability of ME as an antioxidant was determined during radiation processing of lamb meat. ME retarded lipid oxidation, monitored as thiobarbituric acid-reactive substances (TBARS), in radiation-processed lamb meat. TBARS values of ME containing irradiated meat stored at chilled temperatures were significantly lower (p < 0.05) than samples without ME. After 4 weeks of chilled storage, TBARS in irradiated meat containing ME (0.1%) was half of that in untreated irradiated meat.
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In this study, high molecular weight hyaluronic acid in powder form (HMW-HA, with average molecular weight of 1042 kDa) was degraded to low molecular (LMW-HA, 200–230 kDa) by several methods, and the changes in molecular structure and antioxidative activities brought about by each degradation method were compared. The degradation methods used were electron beam irradiation (EB), gamma ray irradiation (GM), microwave irradiation (MW), and thermal treatment (TH). The FT-IR spectra showed no substantial changes of the spectral pattern between HMW and LMW-HAs. However, the UV absorbance of LMW-HA by MW was considerably greater at 265 nm indicating the formation of more double bonds. The antioxidative activities of all LMW-HA samples were found to have risen, but the MW-treated LMW-HA showed the most significant increase due to a newly formed double bond. EB- and GM-treated LMW-HA showed the lowest polydispersity and little change in UV spectra from those of HMW-HA.
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Two polysaccharides, GAPS-1 and SAPS-1, were isolated from the gel and the skin of Aloe barbadensis Miller irrigated with sea water for 3.5 years through a combination of anion-exchange column chromatography and repeated gel chromatography and their chemical characterization and antioxidant activities in vitro were investigated. GAPS-1 and SAPS-1 were composed of Man:Glc:Gal in a ratio of 120:2:3 and 296:36:1 with their molecular weight 1.74 × 105 and 3.97 × 104 Da, respectively. IR and 13C NMR study of GAPS-1 and SAPS-1 demonstrated that the main skeletons of GAPS-1 was β-(1 → 4)-D linkaged mannose with acetylation at C-6 and C-3 of manopyranosyl and SAPS-1 was β-(1 → 4)-D linkaged galactoglucomannan with acetylation at C-6 of pyranosyl. In a concentration-dependent manner, GAPS-1 and SAPS-1 were demonstrated to have strong scavenging activities against superoxide radical, moderate ferrous chelating effect, moderate scavenging activities of hydroxyl radical, moderate reductive power and moderate inhibition of lipid peroxidation. Furthermore, GAPS-1 exhibited moderate scavenging activity of hydrogen peroxide, while SAPS-1 exhibited weak scavenging activity of hydrogen peroxide. GAPS-1 demonstrated more effective antioxidant activities than SAPS-1. The more acetyl group in GAPS-1 molecules probably contributes to the activities.
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A thermal dissociation initiator, potassium persulfate (KPS), is added to the chitosan solution at 70 °C; immediately, the solution viscosity and the molecular weight of chitosan decrease in a very short time. Size exclusion chromatography, nuclear magnetic resonance and electron spin resonance were used to study the degradation mechanism. A free radical degradation mechanism of chitosan by KPS is then proposed. When KPS is thermally dissociated into anionic radicals, they are attracted to the cationic amino group in the chitosan ring. Subsequently, the anionic radical attacks the C-4 carbon and transfers the radical to the C-4 carbon by subtracting the hydrogen from it. The presence of free radical at C-4 carbon eventually results in the breakage of the glycosidic C–O–C bond in the chitosan main chain. According to this mechanism, the concentrations of KPS, total free radicals and the degraded chitosan chain at different degradation times are all calculated by solving the rate equations. Finally, the calculated average molecular weights of the degraded chitosan chains at different reaction times agree with the experimental values.
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Hyaluronan (HA) is a naturally occurring, biocompatible polysaccharide with unique viscoelastic and hygroscopic properties. Its role as a natural lubricant and its excellent water-retaining properties make it well-suited for use in ophthalmic products. Many reports have been written describing the various uses of HA. The purpose of this report is to review the uses of HA in the anterior segment of the eye, more specifically, its use in the treatment of dry eye syndrome, and in contact lenses and contact lens care systems.
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The present study aims to investigate whether Lycium barbarum polysaccharides (LBP) could protect against acute doxorubicin (DOX)-induced cardiotoxicity. Rats received daily treatment of either distilled water (4 ml/kg) or LBP (200mg/kg) for 10 days and then followed by an intravenous injection at day 7 of either saline (10 ml/kg) or DOX (10 mg/kg). DOX induced significantly myocardial damage in rats, which were characterized as conduction abnormalities, decreased heart-to-body weight ratio, increased serum CK, and myofibrillar disarrangement. DOX treatment also increased MDA and decreased SOD and GSH-Px activity in cardiac tissues. Pretreatment with LBP significantly reduced DOX-induced oxidative injury in cardiac tissue, suggesting by the fact that LBP significantly attenuated DOX-induced cardiac myofibrillar disarrangement and LBP was effective in decreasing the levels of serum CK and thus improving conduction abnormalities caused by DOX. LBP treatment significantly increased SOD and GSH-Px activity and decreased the MDA level of heart tissues damaged by DOX exposure in rats. Furthermore, the cytotoxic study showed that LBP protect against cytotoxicity of DOX in cardiac myoblasts H9c2 but dose not attenuate the anti-tumor activity of DOX. In summary, our evidence indicates that LBP elicited a typical protective effect on DOX-induced acute cardiotoxicity via suppressing oxidative stress.
Article
Polygonum cillinerve (Nakai) Ohwi is commonly used in China for over 2000 years. Previous research has shown that the crude polysaccharides extracted from Polygonum cillinerve (Nakai) Ohwi (PCCP) have the scavenging free radicals and anti-tumor activities in vitro. In present study, PCCP were further approached the perspective of their anti-oxidation in immunosuppressed mice. ICR mice were treated firstly with cyclophosphamide (CY, 150 mg/kg), 1 day later, treated with different dosages of PCCP or saline solution once daily for 21 days. Twenty-four hours later for the last drug administration, the animals were weighed, and then killed by decapitation. The liver, spleen, and thymus indices were investigated, and the biochemical parameters were evaluated for various tissues (liver, heart, and kidney). The administration of PCCP with gavage was able to overcome the cyclophosphamide-induced immunosuppression, and significantly to raise the TOC, CAT, SOD, and GSH-Px level. It also raised the liver, spleen, and thymus indices, and decreased the MDA level in mice. PCCP possess the pronounced free radical-scavenging and antioxidant activities, and could play an important role in the prevention of oxidative damage in immunological system.
Article
CD8(+) T cells respond to antigen stimulation through a process of activation, division, and differentiation generating a large pool of activated effector cytolytic T lymphocytes (CTLs). Many cancer patients harbor the accordant precursor CTLs capable of responding to various tumor-associated antigens (TAA). In selected cases, vaccination with these TAA can elicit detectable antitumor responses. Presently, the clinical outcome of cancer vaccination remains inadequate. The lack of clinical efficacy may be attributed to various molecular and cellular mechanisms developed by tumors to successfully evade the host immune system. Some of these mechanisms have been identified. It is becoming increasingly apparent that immunotherapy with the sole objective of inducing immune activation is in itself not sufficient to fully overcome the mechanisms averting efficient antitumor responses. Strategies to neutralize tumor-induced immune suppression have to be developed in parallel to antigenic stimulation. Our data show that both oxidative stress- and antigen-mediated preferential cell death of antigen-experienced memory CTLs may be a major contributor to tumor-induced immune dysfunction. The persistence of functional CTLs is a key element for an efficient antitumor response and affects the outcome of any immunotherapy protocol. We therefore propose that protecting CTLs from premature death by identifying and targeting the responsible pathway can lead to substantial enhancement in antitumor response. In this review, we discuss some of the fundamental factors that may be involved in the modulation of the different lymphocyte subsets towards sensitization or resistance to tumor-induced stress.
Hyaluronan (HA), a component of the extracellular matrix, may regulate immune cell functions through its interactions with cellular receptors. Besides its effect on cytokine and chemokine production, its antioxidant properties have been described. However, the mechanisms of this are not fully elucidated. The aim of this study was to evaluate the relationship between HA concentration and molecular weight and its antioxidant properties towards human neutrophils. Also assessed was whether the antioxidant effect of HA is connected with a reduction in intracellular oxygen potential, which could indicate its direct effect on neutrophil respiratory burst. The relationship between HA's antioxidant properties and its concentration and molecular weight was assessed by the luminol-enhanced chemiluminescence method (CL). To evaluate the effect of HA on intracellular oxygen potential selectively, the dihydrorhodamine 123 (DHR123) flow cytometric method was used. Reduction of both HA molecular weight and its concentration decreased its antioxidant properties in the CL method. A selective effect of HA on intracellular oxygen potential measured by the DHR123 method was not shown. The antioxidant properties of HA are related to both its molecular weight and its concentration. The lack of an antioxidant effect of HA in the DHR123 test compared with a significant reduction in CL values at the same HA concentration suggests that HA acts mainly as a chemical ROI scavenger in the extracellular space.
Article
Cyclophosphamide (Cy) could induce immuno-suppression such as thymus atrophy and inhibition of lymphocyte proliferation response in mice. But, the mechanism of its effect is still not clear. Polysaccharides isolated from spore of Ganoderma lucidum (GL-SP) could, at least partly, restore the immunological effects against Cy-induced immuno-suppression. In the present study, a two-dimensional gel electrophoresis (2-DE)-based comparative proteomic method was conducted to identify the possible target-related proteins of Cy in mice thymus including those could be influenced by GL-SP. Fifteen proteins differentially expressed in Cy-treated mice compared with control were identified. Among the fifteen proteins, combined use of GL-SP with Cy could not affect Cy-induced expression change of three proteins, totally prevented Cy-induced expression change of six proteins, partly prevented Cy-induced expression change of four proteins and further enhanced Cy-induced expression change of two proteins. Results of the present study shed light on the mechanism of Cy-induced immuno-suppression as well as the protective effect of GL-SP against toxicity of Cy.
Article
Oxidative burst provides the mechanism for specialized phagocytes, such as granulocytes or monocytes, to kill invading microorganisms through generation of superoxide anions. However, the oxidants generated during the burst damage DNA of the phagocytes and neighboring cells. Human blood leukocytes treated with phorbol myristate acetate (PMA) are considered to represent the experimental model of induction of oxidative burst. We recently reported that DNA damage in PMA-treated leukocytes is assessed by cytometric analysis of the induction of histone H2AX phosphorylation and Ataxia Telangiectasia Mutated (ATM) activation. In the present study we observed that hyaluronic acid (HA) of average molecular weight (MW) 5.4x10(6) and 2x10(6) at 0.1% (w/v) concentration significantly attenuated H2AX phosphorylation and ATM activation induced in leukocytes during oxidative burst. HA also reduced the intracellular level of PMA-induced reactive oxidants as measured by the ability of cells to oxidize 2',7'-dihydro-dichlorofluorescein-diacetate. No such effect was seen with HA of 6x10(4) MW. The data are consistent with earlier observations that HA of high MW protects DNA from oxidative damage induced by endo- or exogenous oxidants. The anti-oxidant effect of HA seen during oxidative burst also explains its anti-inflammatory effect when used to treat arthritic joints.
Article
Several types of compound exert their cytotoxicity by generating reactive oxygen species, notably the superoxide anion radical. These include quinoid and nitroaromatic compounds serving as redox cyclers, i.e. producing superoxide at the expense of NADPH and oxygen catalyzed by cellular reductases. In specialized cell-types employed in defense such as granulocytes, eosinophils and macrophages, myeloperoxidase, NADPH oxidase and nitric oxide synthase have been identified as major sources of reactive oxygen species in cell toxicity. These include hypochlorite, singlet oxygen, superoxide, nitric oxide and hydrogen peroxide. The interaction of superoxide and nitric oxide generates further oxidants such as peroxynitrite. Lumino-amplified chemiluminescence generated by Kupffer cells is partially sensitive to inhibitors of NO synthase. Superoxide dismutase has been found to catalyze a novel reaction, the reversible conversion of nitric oxide to the nitroxyl anion, the latter being viewed as another form of EDRF. In the defense against oxidative damage, there are enzymatic and nonenzymatic antioxidants. Regarding compounds used pharmacologically, we have been interested in ebselen, a seleno-organic compound exhibiting GSH peroxidase activity, which protects against reactive oxygen species generated, for example, at reoxygenation following a period of hypoxia. Further, we have studied lipoate and dihydrolipoate as antioxidant redox system and as singlet oxygen quencher, e.g. protecting against damage of deoxyguanosines in plasmid DNA generated by singlet oxygen.
Article
Manganese superoxide dismutase (MnSOD), an inductive antioxidant enzyme, can protect cells from oxidative injury to the mitochondria. The elevation of MnSOD activity in cells can effectively prevent many diseases associated with oxidative stress. Polysaccharide Krestin (PSK), a kind of protein-bound polysaccharide extracted from Coriolus versicolor, is used as an immune response modifier in anti-tumor therapy. We have previously found that PSK could alleviate the oxidative injury that oxidized low density lipoprotein (Ox-LDL) brought to monocytes/macrophages, and therefore had some preventive or therapeutic effect on atherosclerosis. In order to find out if the effects of PSK were associated with the alteration ofantioxidant enzymes, we investigated its effect on MnSOD activity and gene expression in mouse peritoneal macrophages. The results showed that PSK could enhance SOD activity and increase the contents ofMnSOD mRNA in mouse peritoneal macrophages. Furthermore, the induction of MnSOD by PSK could be blocked by cycloheximide and actinomycin D.
Article
Fructans are polysaccharides consisting of one glucose unit and two or more fructose units. It was hypothesized that fructans play a role in drought tolerance in plants by interacting directly with the membrane. In this paper we investigated this hypothesis by studying fructan-membrane interactions in hydrated mono- and bilayer systems. It was found that fructans inserted between the headgroups of different kinds of phospholipids with some preference for phosphatidylethanolamine. Insertion occurred even under conditions of very tight lipid packing. The presence of a surface associated layer of fructan was observed in both model systems. This layer was able to reduce the ability of a surface-active protein to interact with the lipids. Fructans showed a much stronger effect on the different lipid systems than other (poly)saccharides, which appears to be related to their hydrophobic properties. Fructans were able to stabilize the liquid-crystalline lamellar phase, which is consistent with a drought protecting role in plants.
Article
Hyaluronic acid protects granulation tissue from oxygen free radical damage and stimulates wound healing, but its molecular weight prevents it from permeating the epidermal barrier A low molecular weight hyaluronic acid preparation is able to permeate the skin, but it is unknown whether or not it retains the scavenging effects of oxygen free radicals in granulation tissue. Our experiments were conducted in rats with excisional or incisional wounds. Wound contraction over 11 days and breaking strength on the fifth day were measured. Oxygen free radical production was induced by intraperitoneal administration of two different xenobiotics: phenazine methosulfate and zymosan. The wounds were treated topically with low molecular weight hyaluronic acid (0.2%) cream or placebo. In the incisional wound group, the effects of superoxide dismutase were also determined. Absolute controls received wounds and placebo but no xenobiotics. Wound healing was significantly slower in the xenobiotic group than in the control groups. These effects were strongly reduced by topical administration of low molecular weight hyaluronic acid (0.2%) cream and in incisional wounds by topically injected superoxide dismutase. Low molecular weight hyaluronic acid is effective as the native compound against oxygen free radicals. Its pharmacological effects through transdermal administration should be tested in appropriate models.
Article
Degradation and the antioxidative effect of Na-, Zn-, Co-, Cu-, and Mn-hyaluronic acid (HA) associates were studied. Our findings revealed the protective effect of certain counterions against ROS-induced HA degradation. We could also separate the antioxidative effect of certain counterions from that of the HA by examining the effect of the counterions in their free ionic forms. The result showed that metal ions with altering oxidative status (Co(2+), Cu(2+), Mn(2+)) proved to be effective in themselves or their effect added to that of HA when HA was also effective. Moreover, the effects of Co-HA against z.rad;O(2)(-) and of Mn-HA against ONOO(-) as well as the synergic effect of Zn-HA associates where Zn(2+) is of fixed oxidative status were attributed to the structure-stabilizing complex formed between certain counterions and HA. Our examination also concerned the influence of HA associates on the indirect antioxidation related to Fe(2+) chelating. The individual effects of Zn(2+), Co(2+), and Cu(2+) were only detectable, which could be explained by the competitive displacement of ferrous from its binding site.
Article
A modification of Dische's carbazole reaction for uronic acid in the presence of borate is described. The advantages of the procedure are: 1.(1) There is an approximately twofold increase of sensitivity. The OD is a linear function of concentration between 4 and 40 μg/ml.2.(2) Maximum color develops immediately.3.(3) The color is stable for at least 16 hr.4.(4) There is greater reproducibility and reduction of interference by chloride ion and oxidants.It has been found possible to distinguish between heparin, heparin derivatives, and other polyuronides of connective tissue by comparing the effect of chlorides on the color yield in both procedures.
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The free radical scavenging activity of the 80% methanolic extracts from fresh leaves of 300 Chinese medical woody plants was assessed with the aid of the stable DPPH radical. Among the plants screened, 56 species had strong free radical scavenging capacities, with IC50 values lower than 0.5 mg leaves per milliliter. Analysis of the medical uses of these plants showed that most of them are employed for their effects on hemostasis, as anti-inflammatory, antimicrobial or for treatment of dysentery. These uses may be directly linked to the content in tannins and flavonoids and consequently to their free radical scavenging activities.
Article
Hepatic fibrosis involves the interplay of many factors including reactive oxygen species. Recent reports described antioxidant properties of glycosaminoglycans (GAGs). Since several findings have shown that hyaluronic acid (HYA) and chondroitin-4-sulphate (C4S) may act as antioxidant molecules, the aim of this research was to evaluate the antioxidant effects of HYA and C4S treatment in a rat model of liver fibrosis. The effect on tissue inhibitors of metalloproteinases (TIMPs) was also studied.
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Recently, intense interest has focused on the antioxidant properties of natural products. In particular, Chinese herbal medicines (CHM) have become hot topics for life science researchers since many are reported to possess cardioprotective compounds, many of which remain to be identified. Indeed, the exact mechanisms by which CHM work remain unknown. Although many of these herbal remedies are undoubtedly efficacious, few have been scientifically investigated for their active chemical constituents and biological activities. We have previously reported higher activities of antioxidant defence enzymes such as superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferases in the liver of rats treated with the herb Salvia miltiorrhiza in a model of acute myocardial infarction. Using well established in vitro antioxidant assays employing 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and diphenyl-l-picrylhydrazyl (DPPH) we have shown that in addition to elevating endogenous antioxidant enzyme activity, Salvia miltiorrhiza and other CHM traditionally used for cardiovascular disorders (such as Rhizoma ligustici, Herba leonuri, Radix achyranthis bidentatae, and Camellia sinensis) contain potent antioxidant moieties in addition to their phenolic constituents. Furthermore, these novel non-phenolic components are effective inhibitors of oxidative reactions mediated by the inflammatory oxidants, peroxynitrite,hypochlorous acid and hydroxyl radical as well as iron-dependent lipid peroxidation. In this review, we discuss the various antioxidant properties of CHM in the context of their biochemical mechanisms.
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The degradation of high-molar-mass hyaluronan (HA) by copper(II) chloride and ascorbate was studied by means of rotational viscometry. It was found that even small amounts of CuCl(2) present in the oxidative system led to the pronounced degradation of HA, reflected in a rapid decrease of the dynamic viscosity of the biopolymer solution. Such degradation was induced by free radicals generated in elevated amounts in the presence of copper ions. Electron paramagnetic resonance investigations performed on a model oxidative system containing Cu(II) and ascorbic acid proved the formation of relatively stable ascorbate anion radicals resulting from the reaction of ascorbic acid with hydroxyl radicals. In this way, by scavenging the hydroxyl radicals, ascorbic acid protected HA from their degradative action. Matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry was applied to analyze the degraded HA. The results showed that only regular fragmentation of hyaluronan occurred using the mentioned oxidative system that led to the formation of HA oligomers with unaffected primary chemical structure.
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Water-soluble polysaccharide(Glycyrrhiza polysaccharide, GP) was isolated from Glycyrrhiza uralensis Fisch, with glycosidic units were composed of alpha (1-4) linked D-glucana. We demonstrated that GP significantly induces nitric oxides (NO) production and inducible NO synthase (iNOS) transcription in peritoneal macrophages. Moreover, iNOS mRNA expression was strongly induced by GP. NO in the culture supernatant was measured by Griess reaction, the production of iNOS was determined by commercially available iNOS kit. GP (10-400 microg/ml) alone increased significantly NO and iNOS production in macrophages. Macrophages simultaneously treated with GP plus lipopolysaccharide (LPS)/interferon-gamma (IFN-gamma) increased NO and iNOS production as compared to that of GP treatments alone. The production of NO and iNOS in macrophages pretreated with LPS followed by GP was higher than that of treatment with GP and LPS simultaneously. Using RT-PCR reveals that GP may provide a second triggering signal for the expression of iNOS mRNA. Thus, the iNOS-mediated NO synthesis in response to GP may be one of the mechanisms whereby this herbal medicine elicits its therapeutic effects.