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Astaxanthin from Haematococcus Pluvialis Prevents Oxidative Stress on Human Endothelial Cells without Toxicity

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Abstract

Astaxanthin, a powerful antioxidant, is a good candidate for the prevention of intracellular oxidative stress. The aim of the study was to compare the antioxidant activity of astaxanthin present in two natural extracts from Haematococcus pluvialis, a microalgae strain, with that of synthetic astaxanthin. Natural extracts were obtained either by solvent or supercritical extraction methods. UV, HPLC-DAD and (HPLC-(atmospheric pressure chemical ionization (APCI)+)/ion trap-MS) characterizations of both natural extracts showed similar compositions of carotenoids, but different percentages in free astaxanthin and its ester derivatives. The Trolox equivalent antioxidant capacity (TEAC) assay showed that natural extracts containing esters displayed stronger antioxidant activities than free astaxanthin. Their antioxidant capacities to inhibit intracellular oxidative stress were then evaluated on HUVEC cells. The intracellular antioxidant activity in natural extracts was approximately 90-times higher than synthetic astaxanthin (5 μM). No modification, neither in the morphology nor in the viability, of vascular human cells was observed by in vitro biocompatibility study up to 10 μM astaxanthin concentrations. Therefore, these results revealed the therapeutic potential of the natural extracts in vascular human cell protection against oxidative stress without toxicity, which could be exploited in prevention and/or treatment of cardiovascular diseases.

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... This would result in a dihydroxy conjugated polyene system, which presents a hydrogen atom that could break the free radical reaction [123,124]. It can also be considered an endothelial protector due these antioxidant properties: it has been demonstrated to inhibit intracellular induced stress in human endothelial cells without any cytotoxicity and modification of the cell morphology [125]. ...
... To counteract the SARS-CoV-2-induced endotheliitis, endothelial barrier protectors such as resveratrol, vitamin D 3 , silicon, vitamin C, and astaxanthin could play a role in ameliorating the endothelial health [125,[163][164][165][166][167][168]. ...
... Proanthocyanidins have also shown antithrombotic properties associated with endothelial protection and inhibition of inflammatory cells adhesion, as it causes a decrease in the expression of P-selectin (thus inhibiting leukocytes and thrombosis) [63,64,165]. Another constituent from Miodesin ® (astaxanthin from Haematococcus pluvialis extract) is also an endothelial protector due its antioxidant properties: it has been demonstrated to inhibit intracellular induced stress in human endothelial cells without any cytotoxicity and modification of the cell morphology [125]. ...
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The number of COVID-19 patients is still growing exponentially worldwide due to the high transmissibility of the SARS-CoV-2 virus. Therapeutic agents currently under investigation are antiviral drugs, vaccines, and other adjuvants that could relieve symptoms or improve the healing process. In this review, twelve therapeutic agents that could play a role in prophylaxis or improvement of the COVID-19-associated symptoms (as add-on substances) are discussed. Agents were identified based on their known pharmacologic mechanism of action in viral and/or nonviral fields and are postulated to interact with one or more of the seven known mechanisms associated with the SARS-CoV-2 virus: (i) regulation of the immune system; (ii) virus entrance in the cell; (iii) virus replication; (iv) hyperinflammation; (v) oxidative stress; (vi) thrombosis; and (vii) endotheliitis. Selected agents were immune transfer factor (oligo- and polypeptides from porcine spleen, ultrafiltered at <10 kDa; Imuno TF®), anti-inflammatory natural blend (Uncaria tomentosa, Endopleura uchi and Haematoccocus pluvialis; Miodesin®), zinc, selenium, ascorbic acid, cholecalciferol, ferulic acid, spirulina, N-acetylcysteine, glucosamine sulfate potassium hydrochloride, trans-resveratrol, and maltodextrin-stabilized orthosilicic acid (SiliciuMax®). This review gives the scientific background on the hypothesis that these therapeutic agents can act in synergy in the prevention and improvement of COVID-19-associated symptoms.
... As a lipophilic molecular, AST can penetrate the capillary endothelial cell to reach these tissue that need it the most, including the central neural system, retina, and skeletal muscle (Wu et al., 2015;Feng et al., 2018). Several lines of evidences suggest that AST confers cytoprotective activities against cancers, diabetes, cardiovascular diseases, neurodegenerative disorders, and acute traumas (Liu et al., 2014;Gammone et al., 2015;R egnier et al., 2015). These favorable effects of AST are closely associated with its oxidative, anti-apoptotic, and antiinflammatory characteristics. ...
... AST functions as a protective molecular against a series of pathologic processes in which the oxidative stress has been implicated (Gammone et al., 2015;R egnier et al., 2015;Galasso et al., 2018). In this study, we show that the emulsifier type can affect the basic physicochemical characteristic of the resulting AST nanodispersions. ...
... As a natural compound, AST is relatively safe and appropriate for chronic application. Currently, several types of AST are commercially available in the forms of nutritional supplements and food additives (Ambati et al., 2014;R egnier et al., 2015). It is well-tolerated in various laboratory experiments and clinical trials without obvious side effects (Fassett & Coombes, 2011). ...
Article
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Astaxanthin (AST) is a naturally occurring carotenoid with potent anti-oxidative and anti-inflammatory potency against chronic diseases. In this study, we suspended AST in different nonionic emulsifiers to produce nanodispersions. The basic physicochemical properties of the produced AST nanodispersions were verified to select the optimized nonionic emulsifier. Among the tested emulsifiers, Polysorbate 20 produced the AST nanoemulsions with smaller particle diameters, narrower size distributions, and higher AST contents among these emulsifiers. The N-methyl-N-nitrosourea (MNU) administered mouse is a chemically induced retinal degeneration (RD) model with rapid progress rate. AST suspended in Polysorbate 20 was demonstrated to ameliorate the dramatic consequences of MNU on retina architectures and function in several different tests encompassing from electrophysiology to histology and molecular tests. Furthermore, the multi-electrodes array (MEA) was used to detect the firing activities of retinal ganglion cells within the inner retinal circuits. We found that AST nanodispersions could restrain the spontaneous firing response, enhance the light induced firing response, and preserve the basic configurations of visual signal pathway in degenerative retinas. The MEA assay provided an appropriate example to evaluate the potency of pharmacological compounds on retinal plasticity. In summary, emulsifier type affects the basic physicochemical characteristic of AST nanodispersions. Polysorbate 20 acts as an optimized nonionic emulsifier for the efficient delivery of AST nanodispersions to retina. AST nanodispersions can alleviate the photoreceptor loss and rectify the abnormities in visual signal transmission.
... Our chromatographic profile of sample 1 that contains Ast-E with different fatty acids is almost the same with the one in the previous reports that studied astaxanthin extracted from H. pluvialis. 8,26 Based on the previous reports, we assigned the position of Ast-mE and Ast-dE in our HPLC results. Because H. pluvialis contains Ast-E bound to fatty acids of different lengths, the first three peaks (between 10 and 18 min) and next peaks (between 20 and 24 min) were predicted to be Ast-mE and Ast-dE, respectively ( Figure 2B). ...
... Specifically, we used 5 μM astaxanthin, which is similar to the concentrations used in previous studies. 26,35 2.5. Cellular Antioxidant Activity. ...
... Next, each sample (samples 1−3) was added to each well along with hydrogen peroxide (H 2 O 2 , at 1 mM; Sigma-Aldrich) to induce oxidative stress for 30 min. 26,52 Finally, the fluorescence intensities were measured on a microplate reader at excitation and emission wavelengths of 485 and 530 nm, respectively. A dose−response curve was established using the blank that had not been treated with H 2 O 2 . ...
Article
Astaxanthin is a strong antioxidant, but the effect of esterification on its biological activities remains unclear. Here, we chemically synthesized three forms of astaxanthin (nonesterified (Ast-N), monoesterified (Ast-mE), and diesterified (Ast-dE) forms) using esterified astaxanthin (Ast-E) in natural extract from Haematococcus pluvialis and characterized them by spectrophotometry and high-performance liquid chromatography (HPLC). Additionally, the antioxidant and anti-inflammatory activities of the samples containing three forms of astaxanthin at different ratios were evaluated. The sample containing the maximum level of Ast-mE compared to those of Ast-N and Ast-dE showed the highest antioxidant and anti-inflammatory activities. We also observed the greatest increase in expression of genes related to antioxidant and anti-inflammatory effects in samples containing the highest Ast-mE. These results provide a foundation for in-depth investigation of astaxanthin and other antioxidant molecules, allowing for the development of a practical and cost-effective strategy to improve antioxidant or anti-inflammatory activities of natural extracts that can be used as dietary supplements.
... The antioxidant activity of the SUPRAS extracts obtained under the optimal conditions specified in Section 2.5 was evaluated by the DPPH, TEAC [34] and FRAP [35] methods. Control assays with Trolox were run in parallel for TEAC. ...
... Control assays with Trolox were run in parallel for TEAC. The decrease of the absorbance of the reagent solutions, measured as inhibition, was calculated from the following equation [34]: ...
Article
Supramolecular solvents (SUPRAS) were investigated for the recovery of bioactives from coffee wastewater (CWW), an abundant residue in the wet and semi-wet processing methods of coffee beans. SUPRAS were made up of hexagonal inverted aggregates of hexanol or decanoic acid and were spontaneously produced in the wastewater through self-assembly processes. SUPRAS components were food authorized ingredients this facilitating future industrial applicability. Under passive extraction (energy-less procedure), caffeine was recovered with a yield of 54 to 65 mg per liter of wastewater. SUPRAS extracts showed good antioxidant capacity (up to 53% ABTS•+) and were stable for at least 2 months in the range of temperatures investigated (4-24 ºC) for the preservation of bioactives. Additionally, the SUPRAS-based extraction of bioactives improved substantially some wastewater quality parameters (e.g. BOD, total suspended solids and conductivity), so this process also helped to purify wastewater before dumping it to surface waters.
... It is also known to protect cells and tissues against lipid peroxidation and oxidative damage. [7][8][9] Several studies have reported the beneficial effects of ASX to treat patients with hypertension. The development of new, effective, and easy-to-take forms of ASX is required to prevent hypertension because they are currently difficult to take as a daily supplement. ...
... In fact, ASX has been reported to prevent oxidative stress in human ECs without cytotoxicity and reduce in the risk of oxidative-stress by its antioxidant capacity. 9) These results may suggest that ASX-E administration before hypertension development decreases the ROS levels in the blood and maintains endothelial function. ...
Article
The aim of this study was to investigate the effects of egg yolk powder enriched with astaxanthin (ASX-E) on blood pressure in spontaneously hypertensive rats (SHR) and to verify the benefits of ASX-E as a functional food. To investigate the antihypertensive effect, SHR were fed with an ASX-E mixed diet before hypertension development. Blood pressures were determined periodically during the study by the tail-cuff method. At the end of the study, animals were euthanized, and their thoracic aortas were collected to determine vascular conductance. The thoracic aorta tension was measured with a force displacement transducer. Concentration-dependent response relationships were determined by cumulative addition of 10⁻⁹–10⁻⁴ M Carbamoylcholine (Cch). Blood pressures of the SHR in the ASX-E mixed diet group were ASX-dose-dependently lower than that of those in the control group. In SHR fed with an ASX-E mixed diet, Cch induced vasorelaxation in the thoracic aorta with endothelium lining but not without endothelium. However, the antihypertensive effect of ASX-E was not observed on blood pressures in SHR that were fed with ASX-E only after the development of hypertension. Results suggest that ASX-E protects endothelial function and thereby prevents the development of hypertension. Hence, the results of our research indicate that daily consumption of ASX-E has a potential benefit on human health. Graphical Abstract Fullsize Image
... Cells were pretreated with THSG in DMSO at a concentration of 0, 30, 100, or 200 µM for 2 h. To avoid the significant toxicity and side effects of DMSO on the cells, the final concentration of DMSO used in this study was lower than 0.1% v/v, which is welltolerated with no observable toxic effects to endothelial cells [48][49][50]. In a separate experiment, cells were pre-incubated for 2 h with THSG (100 µM), NAC (N-Acetyl-L-cysteine; 10 mM; Cat. ...
... To determine the optimal concentration of apocynin for our study model, we treated brain endothelial cells with various concentrations of apocynin (50,100,200, and 300 µM). We did not observe cell toxicity when apocynin was administered alone at the indicated concentrations (Supplementary Figure S1A). ...
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We recently reported that the periodontopathic bacteria Porphyromonas gingivalis (P. gingivalis) initiates an inflammatory cascade that disrupts the balance of reactive oxygen species (ROS), resulting in apoptotic cell death in brain endothelial cells. An extract from Polygonum multiflorum Thunb., 2,3,5,4′-Tetrahydroxystilbene-2-O-β-glucoside (THSG) has been well-reported to diminish the inflammation in many disease models. However, the effects of THSG in the area of the brain–oral axis is unknown. In this study, we examined the effects of THSG in P. gingivalis-stimulated inflammatory response and apoptotic cell death in brain endothelial cells. THSG treatment remarkably lessened the upregulation of IL-1β and TNF-α proteins in bEnd.3 cells infected with P. gingivalis. Treatment of THSG further ameliorated brain endothelial cell death, including apoptosis caused by P. gingivalis. Moreover, the present study showed that the inhibitory effects on NF-κB p65 and antiapoptotic properties of THSG is through inhibiting the ROS pathway. Importantly, the ROS inhibitory potency of THSG is similar to a ROS scavenger N-Acetyl-L-Cysteine (NAC) and NADPH oxidase inhibitor apocynin. Furthermore, the protective effect of THSG from P. gingivalis infection was further confirmed in primary mouse brain endothelial cells. Taken together, this study indicates that THSG attenuates an ROS-dependent inflammatory response and cell apoptosis in P. gingivalis-infected brain endothelial cells. Our results also suggest that THSG could be a potential herbal medicine to prevent the risk of developing cerebrovascular diseases from infection of periodontal bacteria.
... The Astx-E content was found to be almost 8 times higher than free Astx. It has been reported that Astx-E has a higher antioxidant activity compared to free Astx [32]. Thus, high amounts of Astx-E found in our shrimp extract compared to free Astx suggests it may have better health potential than free Astx. ...
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The province of Newfoundland and Labrador, Canada, generates tons of shrimp processing by-product every year. Shrimp contains omega (n)-3 polyunsaturated fatty acids (PUFA) and astaxanthin (Astx), a potent antioxidant that exists in either free or esterified form (Astx-E). In this study, shrimp oil (SO) was extracted from the shrimp processing by-product using the Soxhlet method (hexane:acetone 2:3). The extracted SO was rich in phospholipids, n-3 PUFA, and Astx-E. The 3T3-L1 preadipocytes were differentiated to mature adipocytes in the presence or absence of various treatments for 8 days. The effects of SO were then investigated on fat accumulation, and the mRNA expression of genes involved in adipogenesis and lipogenesis in 3T3-L1 cells. The effects of fish oil (FO), in combination with Astx-E, on fat accumulation, and the mRNA expression of genes involved in adipogenesis and lipogenesis were also investigated. The SO decreased fat accumulation, compared to untreated cells, which coincided with lower mRNA expression of adipogenic and lipogenic genes. However, FO and FO + Astx-E increased fat accumulation, along with increased mRNA expression of adipogenic and lipogenic genes, and glucose transporter type 4 (Glut-4), compared to untreated cells. These findings have demonstrated that the SO is a rich source of n-3 PUFA and Astx-E, and has the potential to elicit anti-adipogenic effects. Moreover, the SO and FO appear to regulate adipogenesis and lipogenesis via independent pathways in 3T3-L1 cells.
... Because there was a negative effect of the relatively greater ASX concentration in Experiment 1 of the present study, there was not an evaluation of the relatively greater concentrations of the antioxidant in the two subsequent experiments. Based on results from previous studies, ASX did have any associated or toxic effects regardless of the concentration used in clinical studies (Fassett and Coombes, 2009;Régnier et al., 2015;Zhang and Wang, 2015). The results of the present study, therefore, could be explained by the cumulative effect of antioxidants or/and the interaction between constituents of ASX and EY. ...
Article
The aim of the study was to determine whether the presence of astaxanthin (ASX) protects boar spermatozoa against damage related to cryopreservation. Pooled ejaculates extended in Beltsville Thawing Solution (BTS) were used. Three experiments were conducted: 1) sperm samples were pre-incubated overnight (17 °C) with ASX (0, 0.5, 5, 15 μM) prior to freezing and then frozen using cooling and thawing extenders supplemented with ASX (0, 0.5, 5, 15 μM); 2) sperm samples were treated with ASX (0, 0.5, 5, 15 μM) only during overnight pre-incubation (17 °C) prior to cryopreservation; and 3) a thawing extender was supplemented with ASX (0, 0.5, 5, 15 μM). The groups were as follows: control (C; no treatment), ASX 1 (0.5 μM), ASX 2 (5 μM) and ASX 3 (15 μM). Total (TM) and progressive (PM) motility was analyzed using CASA, while sperm viability, reactive oxygen species generation, lipid peroxidation and apoptoticlike changes were analyzed using flow cytometry. Sperm variables were evaluated prior to freezing as well as 30 and 150 min after thawing. In Experiment 1, the values of TM and sperm viability post-thaw were less in the ASX 3 than C group. In Experiment 2, there was no effect of ASX on any of the sperm variables evaluated, while in Experiment 3, apoptotic-like changes were less in the ASX 1 than C group. In conclusion, there was a subtle beneficial effect on cryopreserved boar spermatozoa after addition of ASX to thawing media.
... In fact, synthetic astaxanthin, which is derived from petrochemicals, raise the risks on food safety, pollution, and sustainability; thus it is not allowed for human consumption and animal feed [94]. R egnier et al. [116] reported that the intracellular antioxidant of astaxanthin derived from H. pluvialis was 90-fold higher than that in synthetic astaxanthin. The market value of this astaxanthin source is estimated in a range from US$2500 to US$15,000kg À1 , depending on products' purity [114,117]. ...
Chapter
Astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4-dione) is a known to be valuable carotenoid with strong antioxidant, which has been extensively used in various industries (such as aquaculture, nutraceutical, pharmaceutical, and food). There have been two major sources of astaxanthin: chemical (synthetic) and biological (natural) source. In nature, astaxanthin can be synthesized by plants, crustaceans by-product, bacteria, a few fungi, and green algae, in which microalga Haematococcus pluvialis is an appropriate source of natural astaxanthin exploitation that seems to be gaining potential in the market. Technology for natural astaxanthin production is an expensive process, depending on each producer, in each country. Therefore, continuous efforts were necessary to improve the different culture systems (photobioreactor (PBR) and open pond), culture models (heterotrophic and photoautotrophic), culture methods, harvesting, and astaxanthin extraction processes for enhanced production of astaxanthin-rich biomass and cost reduction in large-scale culture. In this chapter, we summarized about astaxanthin production and technology for its production in Vietnam and other Asian countries to get a more general view of this valuable product.
... This microalga is a source of astaxanthin, a compound belonging to xanthophyll type, with antioxidant and anticancer properties (Ranga Rao et al., 2014;Capelli and Cysewski, 2018). Astaxanthin can be used as nutritional supplement with human health benefits such as anti-inflammatory and anticancer agent and it is widely used in pharmacology to cure cardiovascular diseases (Regnier et al., 2015;Chacon-Lee and González-Mariño, 2010). Also, as shown by Walker et al. (2005) it has positive effects to prevent diabetes type 2 and neurodegenerative disorders. ...
Article
In either unicellular or multi-cellular form, microalgae are photosynthetic microorganisms, mainly known for being part of the human diet in several world regions. More recently, they have been in the spotlight of researchers, not only because of their nutritional value, but also due to their high value-added components. This work reviews five microalgae genera: Dunaliella, Botryococcus, Chlamydomonas, Chlorella and Arthrospira, considered among the most promising for commercial biotechnological applications. The analysis shows that, although the research paradigms are generally shared among species, parameterization changes of culture environment and stress conditions, several applications can be envisaged for the cultivated species, which is discussed in this work. Besides, several applications in which these microalgae are being widely used, or are intended to be used, are analyzed and discussed. The potential applications depend on the type of metabolites found in each microalgae species, which is discussed in this work, giving examples of application and describing methods for their cultivation, harvesting and biomass processing. Thus, in addition to being used in human diet supplementation, microalgae can be used as ingredients for animal feed, medicines, cosmetics pigments, biofuels, bioplastics and biostimulants.
... α-carotene, β-carotene, and lycopene) at different ratios for the quantification of endogenous pigments in the fruits of WT plants and mutant lines. Carotenoids were quantified based on their established retention time and specific absorption spectrum [60,61]. At least three independent extractions were performed for each mutant. ...
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Tomato ripening is a complex and dynamic process coordinated by many regulatory elements, including plant hormones, transcription factors, and numerous ripening-related RNAs and proteins. Although recent studies have shown that some RNA-binding proteins are involved in the regulation of the ripening process, understanding of how RNA-binding proteins affect fruit ripening is still limited. Here, we report the analysis of a glycine-rich RNA-binding protein, RZ1A-Like (RZ1AL), which plays an important role in tomato ripening, especially fruit coloring. To analyze the functions of RZ1AL in fruit development and ripening, we generated knockout cr-rz1al mutant lines via the CRISPR/Cas9 gene-editing system. Knockout of RZ1AL reduced fruit lycopene content and weight in the cr-rz1al mutant plants. RZ1AL encodes a nucleus-localized protein that is associated with Cajal-related bodies. RNA-seq data demonstrated that the expression levels of genes that encode several key enzymes associated with carotenoid biosynthesis and metabolism were notably downregulated in cr-rz1al fruits. Proteomic analysis revealed that the levels of various ribosomal subunit proteins were reduced. This could affect the translation of ripening-related proteins such as ZDS. Collectively, our findings demonstrate that RZ1AL may participate in the regulation of carotenoid biosynthesis and metabolism and affect tomato development and fruit ripening.
... Haematococcus pluvialis is considered the finest production source of ATX industrially (Shah et al., 2016). This ATX from H. pluvialis hinders the oxidative stress inside the cells (Régnier et al., 2015). ATX is also obtained from other microalgae like C. sorokiniana, C. zofingiensi, Tetraselmis sp., Chlorococcum sp. and G. sulphuraria (Li et al., 2001a;Ip and Chen, 2005;Raman and Mohamad, 2012;Graziani et al., 2013). ...
Article
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Though cancer therapeutics can successfully eradicate cancerous cells, the effectiveness of these medications is mostly restricted to several deleterious side effects. Therefore, to alleviate these side effects, antioxidant supplementation is often warranted, reducing reactive species levels and mitigating persistent oxidative damage. Thus, it can impede the growth of cancer cells while protecting the normal cells simultaneously. Moreover, antioxidant supplementation alone or in combination with chemotherapeutics hinders further tumor development, prevents chemoresistance by improving the response to chemotherapy drugs, and enhances cancer patients’ quality of life by alleviating side effects. Preclinical and clinical studies have been revealed the efficacy of using phytochemical and dietary antioxidants from different sources in treating chemo and radiation therapy-induced toxicities and enhancing treatment effectiveness. In this context, algae, both micro and macro, can be considered as alternative natural sources of antioxidants. Algae possess antioxidants from diverse groups, which can be exploited in the pharmaceutical industry. Despite having nutritional benefits, investigation and utilization of algal antioxidants are still in their infancy. This review article summarizes the prospective anticancer effect of twenty-three antioxidants from microalgae and their potential mechanism of action in cancer cells, as well as usage in cancer therapy. In addition, antioxidants from seaweeds, especially from edible species, are outlined, as well.
... The separation yield was 20.6 mg/L at 92.0% purity, and by further one-step silica gel chromatography, the purity on N-ASX from P. rhodozyma was 99.0%. Some reports claim that esterified N-ASX has better or equal pharmacological properties than free N-ASX, which is also unstable and susceptible to oxidation (Rao et al., 2015;Régnier et al., 2015). Due to this, some studies have focused on the purification of the esterified N-ASX. ...
Article
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Astaxanthin (ASX) is a xanthophyll pigment considered as a nutraceutical with high antioxidant activity. Several clinical trials have shown the multiple health benefits of this molecule; therefore, it has various pharmaceutical industry applications. Commercial astaxanthin can be produced by chemical synthesis or through biosynthesis within different microorganisms. The molecule produced by the microorganisms is highly preferred due to its zero toxicity and superior therapeutic properties. However, the biotechnological production of the xanthophyll is not competitive against the chemical synthesis, since the downstream process may represent 70–80% of the process production cost. These operations denote then an opportunity to optimize the process and make this alternative more competitive. Since ASX is produced intracellularly by the microorganisms, high investment and high operational costs, like centrifugation and bead milling or high-pressure homogenization, are mainly used. In cell recovery, flocculation and flotation may represent low energy demanding techniques, whereas, after cell disruption, an efficient extraction technique is necessary to extract the highest percentage of ASX produced by the cell. Solvent extraction is the traditional method, but large-scale ASX production has adopted supercritical CO 2 (SC-CO 2 ), an efficient and environmentally friendly technology. On the other hand, assisted technologies are extensively reported since the cell disruption, and ASX extraction can be carried out in a single step. Because a high-purity product is required in pharmaceuticals and nutraceutical applications, the use of chromatography is necessary for the downstream process. Traditionally liquid-solid chromatography techniques are applied; however, the recent emergence of liquid-liquid chromatography like high-speed countercurrent chromatography (HSCCC) coupled with liquid-solid chromatography allows high productivity and purity up to 99% of ASX. Additionally, the use of SC-CO 2 , coupled with two-dimensional chromatography, is very promising. Finally, the purified ASX needs to be formulated to ensure its stability and bioavailability; thus, encapsulation is widely employed. In this review, we focus on the processes of cell recovery, cell disruption, drying, extraction, purification, and formulation of ASX mainly produced in Haematococcus pluvialis , Phaffia rhodozyma , and Paracoccus carotinifaciens . We discuss the current technologies that are being developed to make downstream operations more efficient and competitive in the biotechnological production process of this carotenoid.
... Astaxanthin from H. pluvialis inhibits the oxidative stress inside the cells [50]. ...
... Astaxanthin from H. pluvialis inhibits the oxidative stress inside the cells [50]. ...
Chapter
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In cancer treatment, increase in drug resistance and decrease in new chemotherapeutic drugs have become a pressing problem. Hence, searching for novel anticancer agents with less toxicity and high sensitivity is expanding gradually. Many preclinical and clinical studies indicate that natural antioxidants can help combating carcinogenicity and reduce the adverse effects on cancer therapy, when used alone or as adjuvant in chemotherapy. Consequently, marine algae pave the way for exploring more potential antioxidant compounds which have pharmaceutical importance. Algal terpenoids comprise a large group of bioactive compounds that have excellent antioxidative property and can be used as source of antioxidant in cancer therapy. This chapter summarizes the potential role of terpenoids from algal sources in inhibiting cancer cells, blocking cell cycle, hindering angiogenesis and metastasis as well as in inducing apoptosis.
... The stronger antioxidant capacity of natural extracts containing ASTX esters over free ASTX was also evidenced by the Trolox equivalent antioxidant capacity (TEAC) assay. Moreover, when evaluated on HUVEC cells, the intracellular antioxidant activity of H. pluvialis extract was approximately 90 times higher than synthetic astaxanthin [29]. ...
Article
Haematococcus pluvialis is a green microalga that produces a considerable amount of carotenoids, mainly astaxanthin (ASTX), which is a powerful antioxidant compound. However, carotenoid compounds exhibit poor water solubility and high instability, which restrain their application in pharmaceutical products. Considering that, here we describe the encapsulation of Haematococcus pluvialis carotenoids into poly-lactide-co-glycolide nanocapsules (NC-ESHp), aiming to obtain an innovative topical product with antioxidant properties. Nanocapsules were prepared by the solvent displacement method and characterized according to size, zeta potential, total carotenoid content, and ASTX content. Poloxamer 407 was added to the colloidal dispersion to form a thermosensitive hydrogel (HG–NC–ESHp). Release studies demonstrated that the carotenoids were released from the gel system in a sustained way. In the DPPH scavenging assay, NC-ESHp15 exhibited an antioxidant activity 9-fold higher than ascorbic acid. These results indicated that the hydrogel developed may be a promising formulation to provide prolonged protection of the skin against the photo-oxidation process.
... The reason fir which AST-monoester shows a stronger antioxidant than AST-diester and free AST may be due to the high electron donation activity of one hydroxyl group esterified with fatty acid to the ROO · , thus terminating the peroxide chain reaction. Earlier, Régnier, Bastias [28] described that the ORAC value for chemical extraction and high-pressure processing was higher than the Dimethyl Sulphoxide (ORAC value: 8.1 µM TE/g of AST) on extractions from H pluvialis, because the natural extracts comprising esters exhibited more powerful antioxidant activities than free AST. ...
Article
: In this study, the impact of different cell disruption techniques (high-pressure micro fluidization (HPMF), ionic liquids (ILs), multi-enzyme (ME), and hydrochloric acid (HCl)) on the chemical composition and biological activity of astaxanthin (AST) obtained from Haematococcus pluvialis was investigated. Results indicated that all cell disruption techniques had a significant effect on AST composition, which were confirmed by TLC and UPC2 analysis. AST recovery from HCl (HCl-AST) and ILs (ILs-AST) cell disruption techniques was dominant by free and monoesters AST, while AST recovery from HPMF (HPMF-AST) and ME (ME-AST) cell disruption techniques was composed of monoesters, diesters, and free AST. Further biological activity analysis displayed that HCl-AST showed the highest ABTS and DPPH activity, while ILs-AST showed better results against the ORAC assay. Additionally, ILs-AST exhibits a stronger anti-proliferation of HepG2 cells in a dose-dependent manner, which was ascribed to AST-induced ROS in to inhibit the proliferative of cancer cells.
... The calibrated samples were mixed to generate multiple-diluted external calibration curves for the quantification of the pigments. Carotenoids were identified based on typical retention times and specific published absorption spectra (Mialoundama et al., 2010;Regnier et al., 2015). ...
... Research by previous studies has proven that ASX at higher doses is non-toxic to mice and human endothelial cells. [61][62][63][64] Related clinical studies have also been conducted into cardiovascular disease to assess the dosing, bioavailability, and safety of ASX. [19] To date, no significant side effects related to ASX have been reported. ...
Article
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Cancer is a disease in which a group of abnormal cells grow uncontrollably by disregarding the normal rules of cell division. Across several cancers, Hepatocellular carcinoma (HCC) is one of the most aggressive cancers in worldwide. It is held responsible for up to 1 million deaths globally per annum. HCC is an inflammation-related cancer, as a chronic inflammatory state is necessary for cancer appearance. In this study, the drug astaxanthin and encapsulated astaxanthin was tested against HCC. Mice were divided into 7 groups; Group I: control, Group II: DEN induced, Group III: DEN + 50 mg/kg astaxanthin, Group IV: DEN + 100 mg/kg astaxanthin, Group V: DEN + 50 mg/kg encapsulated astaxanthin, Group VI: DEN + 100 mg/kg encapsulated astaxanthin, Group VII: DEN + 10 mg/kg sorafenib. Regular diet was given. Body weight, Food intake, water intake was noted. Other biochemical parameters such as ALP, AST, Albumin, proteins and TNF-α was determined. Finally, the liver was removed from each mice of different group by sacrificing them and histopathology was done. In vivo evaluation in mice models showed significant antitumor activities by both encapsulated and non-encapsulated astaxanthin at 100 mg/kg as compared with the control, DEN induced group and positive drug sorafenib. This research suggested that encapsulated astaxanthin can also be used as chemotherapeutic agent for the treatment of Hepatocellular carcinoma (HCC).
... The reason fir which AST-monoester shows a stronger antioxidant than AST-diester and free AST may be due to the high electron donation activity of one hydroxyl group esterified with fatty acid to the ROO · , thus terminating the peroxide chain reaction. Earlier, Régnier, Bastias [28] described that the ORAC value for chemical extraction and high-pressure processing was higher than the Dimethyl Sulphoxide (ORAC value: 8.1 µM TE/g of AST) on extractions from H pluvialis, because the natural extracts comprising esters exhibited more powerful antioxidant activities than free AST. ...
Article
Citation: Tan, Y.; Ye, Z.; Wang, M.; Manzoor, M.F.; Aadil, R.M.; Tan, X.; Liu, Z. Comparison of Different Methods for Extracting the Astaxanthin from Haematococcus pluvialis: Chemical Composition and Biological Activity. Molecules 2021, 26, 3569. https://doi. Abstract: In this study, the impact of different cell disruption techniques (high-pressure micro fluidization (HPMF), ionic liquids (ILs), multi-enzyme (ME), and hydrochloric acid (HCl)) on the chemical composition and biological activity of astaxanthin (AST) obtained from Haematococcus pluvialis was investigated. Results indicated that all cell disruption techniques had a significant effect on AST composition, which were confirmed by TLC and UPC 2 analysis. AST recovery from HCl (HCl-AST) and ILs (ILs-AST) cell disruption techniques was dominant by free and monoesters AST, while AST recovery from HPMF (HPMF-AST) and ME (ME-AST) cell disruption techniques was composed of monoesters, diesters, and free AST. Further biological activity analysis displayed that HCl-AST showed the highest ABTS and DPPH activity, while ILs-AST showed better results against the ORAC assay. Additionally, ILs-AST exhibits a stronger anti-proliferation of HepG2 cells in a dose-dependent manner, which was ascribed to AST-induced ROS in to inhibit the proliferative of cancer cells.
... Commercially, astaxanthin is mainly offered as an oleoresin, in which only 10-15% (w/w) corresponds to total astaxanthin, being the majority composed by acylglycerols and other minor carotenoids (Shah et al., 2016). In fact, esterified astaxanthin may be responsible for biological properties attributed to the free astaxanthin form, once these oleoresins are considered to be composed by the latter, overlooking the fact that this pigment is present in only low amounts (Holtin et al., 2009;Régnier et al., 2015;Richard et al., 2008). In a study conducted by Hosseini et al. (2020), the biomass of microalga H. pluvialis was mainly composed of carbohydrates, followed by proteins and lipids, and minor content of ash and moisture. ...
Article
The increased demands and dependence on depleted oil reserves, accompanied by global warming and climate change have driven the world to explore and develop new strategies for global sustainable development. Among sustainable biomass sources, microalgae represent a promising alternative to fossil fuel and can contribute to the achievement of important Sustainable Development Goals (SDGs). This article has reviewed the various applications of microalgal biomass that includes (i) the use in aquaculture and its sustainability; (ii) commercial value and emerging extraction strategies of carotenoids; (iii) biofuels from microalgae and their application in internal combustion engines; (iv) the use and reuse of water in microalgae cultivation; and (v) microalgae biotechnology as a key factor to assist SDGs. The future prospects and challenges on the microalgae circular bio economy, issues with regard to the scale-up and water demand in microalgae cultivation are also highlighted.
... On the other hand, the ORAC method produced the lowest value of 5.22 µmol TE/100 g of OE in our study. The ORAC values reported in other studies, functional food samples enriched with astaxanthin from other H. pluvialis strains, were higher than the values reported herein [51,52]. Other species such as Arthrospira maxima have also been considered important sources of high-quality nutrients, exhibiting higher ORAC values ranging between 90-519 TE/g of biomass [53]. ...
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Haematococcus pluvialis is known to be a natural source of antioxidants for numerous applications. In this study, an oleoresin rich in carotenoids extracted by supercritical CO2 treatment of H. pluvialis was extensively characterized for its antioxidant capacity. Carotenoid content, fatty acid profile, total phenol content, antioxidant capacity, and viscosity of the oleoresin were determined with the aim of ascertaining the potential of the oleoresin in terms of its antioxidant content for food applications. The oleoresin contained 96.22 mg/g of total astaxanthin (which includes free astaxanthin and astaxanthin esters) and mostly included unsaturated fatty acids (~78% of total fatty acids). High total phenol content and ferric reducing antioxidant potential indicated high antioxidant capacity, but oxygen radical absorbance capacity was lower compared to the oleoresin samples obtained from other species. The oleoresin was a non-Newtonian fluid since it had shear-thinning (pseudoplastic) and shear-thickening (dilatant) flow. Therefore, the H. pluvialis oleoresin is a potential alternative in developing functional ingredients for designing healthy food products. To the best of our knowledge, this is the first study that has reported an extensive characterization of the antioxidant properties of a microalgal oleoresin obtained by means of supercritical CO2 fluid extraction.
... Besides Haematococcus pluvialis (standard ASX-producing algal strains) [12,42,43], other microalgae species are also used to produce a natural ASX, like Chlorella zofingiensis [44], Chlorella protothecoides [45], Scenedesmus sp [46] and Neochloris wimmeri [47] with a low amount of ASX (1.1 to 10.72 mg L −1 ). Therefore, there is great need to isolate and identify novel algal strains that can sustain high growth rates and accumulate higher ASX. ...
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Synthesized astaxanthin (ASX), stereoisomers of 3S,3′R, 3R,3′R, and 3S,3′S, have over 95% market share and have relatively poor antioxidant and bioactivity properties, with persistent issues in terms of biological functions, health benefits, and biosafety if compared to natural ASX. Bioprospecting of new microalgal strains could be vital for a new source of powerful antioxidant (ASX). In this study, a new algal strain was isolated from the Indian foothills of the Himalayas. Its identity was discerned by morphological and DNA barcode studies. It is a unicellular spheroidal cell-shaped alga with 100–200 μm diameter. The isolate has 93.4% similarity to Dysmorphococcus globosus species based on 18S-rDNA phylogenetic analysis and named as D. globosus-HI (HI stands for Himalayan India). Its growth and major cellular components (carotenoids, carbohydrates, protein, lipids, fatty acid profile, and ASX) were optimized using the seven different culture media. The highest biomass (1.14 g L−1) was observed in the MBBM medium, with a specific growth rate (0.087 day−1), division/day (0.125), and cellular yield (6.16 x 106 cells/mL). The highest carotenoids (1.56 mg g−1), lipids (32.5 mg L−1), and carbohydrates (135.62 mg L−1) were recorded in the 3N-BBM medium. The maximum ω3-FAs (17.78%), ω6-FAs (23.11%), and ω9-FAs (7.06%) were observed in MBBM, JW, and BG-11 medium respectively. The highest amount of antioxidant ASX was accumulated in the 3N-BBM medium (391 mg L−1). It is more than any other known algal species used in the production of natural ASX. The optimized biochemical studies on the D. globosus-HI strain should fulfill the increasing demand for natural ASX for commercial application.
... In this study, DHA supplementation significantly enhanced Axn deposition in the ovaries and hepatopancreas of E. sinensis. The reason for the positive effects of dietary DHA on Axn deposition could be explained by the following facts: (1) Synthetic Axn is all in its free form and thus is vulnerable to oxidation, but the esterification of free Axn with LC-PUFA (monoes-ters and diesters) may improve molecular stability and facilitate higher solubility rates in crustacean tissues [75][76][77]. Moreover, dietary supplementation of DHA oil facilitates the esterification of free Axn in animal tissue, which may lead to increased Axn deposition in the tissues of E. sinensis. ...
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Astaxanthin (Axn) is an essential carotenoid for crustacean pigmentation, and docosahexaenoic acid (DHA) is an important fatty acid; both play key roles in maintaining the health of many aquaculture species. The present study explored the combined effect of dietary Axn and DHA on gonadal development and carotenoid deposition in adult females of the Chinese mitten crab, Eriocheir sinensis. A 2 × 3 factorial design of experimental diets was created to contain two levels of Axn (0 mg/kg and 100 mg/kg) and three levels of DHA oil (0%, 0.33%, and 0.67%). The results showed as follows: (1) For the culture performance, dietary DHA oil significantly increased the gonadosomatic index (GSI), and Diet 2 (Axn 0% + DHA oil 0.33%) had the highest GSI among all treatments. (2) For the enzymatic indicators in the hepatopancreas and hemolymph, supplementation with 0.33% DHA oil significantly improved the antioxidant capacity (T-AOC and MDA), immunity (AKP and ACP), and health status (e.g., GPT and GOT) of E. sinensis. (3) Supplementation with 100 mg/kg Axn significantly increased redness (a ∗ ) and Axn concentration in both the ovaries and hepatopancreas, and supplementation with 0.33% or 0.67% DHA oil produced a further significant improvement in Axn concentration when the diets were supplemented with 100 mg/kg of Axn. (4) As for proximate composition, dietary Axn and DHA significantly increased the deposition of total lipids and triacylglycerol in the hepatopancreas. As expected, the crabs fed diets with DHA supplementation showed an increase in the DHA percentage and DHA/EPA ratio in the ovaries and hepatopancreas. In conclusion, dietary Axn and DHA oil had positive effects on ovarian development in E. sinensis females. The optimal combination of dietary Axn and DHA oil was determined to be approximately 100 mg/kg and 0.33%, respectively, for this species during ovarian maturation.
... Another common way to evaluate the antioxidant power generated mainly by the natural astaxanthin contained in H. pluvialis is by contrast with its synthetic alternative. Thus, the mean TEAC values of synthetic astaxanthin range between 2.21 and 2.43 mmolTE g −1 DW Régnier et al. 2015) which, despite being higher than the values obtained for the ethanol extract of H. pluvialis MSPD in red phase, is synthesised by petrochemical processes that often raise alarming food safety issues with potential toxicity in the final product (Jeevanandam et al. 2020). In addition, synthetic production also presents challenges in terms of sustainability and potential environmental impact in the manufacturing process (Li et al. 2011). ...
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This study provides an efficient alternative by extracting bioactive compounds from Haematococcus pluvialis via matrix solid-phase dispersion (MSPD) from its wet form, reducing one of the process steps with the greatest economic impact, the drying of the microalga. To obtain a suitable extract for nutraceutical purposes, solvents with the generally recognised as safe (GRAS) designation (ethanol, ethyl lactate, and ethyl acetate) with limitations of use (acetone) and extractants with higher toxicity such as methanol and methyl-tert-butyl ether (MTBE) are contrasted. Through the optimisation of the extractive process, ethanol, a GRAS solvent, presents the best overall recovery for carotenoid compounds and fatty acids, showing an antioxidant activity of 1.58 mmolTE g ⁻¹ DW, comparable to its synthetic alternative of petrochemical origin without the drawback of having limitations in its food use. In addition, the identification of the phenolic compounds, phloroglucinol, p- coumaric acid, gallic acid, and catechin, not previously characterised in red stage H. pluvialis , provides a response to the phenolic activity present in the extract (24.65 mmolGAE g ⁻¹ DW). Comparison of the extractive efficiency obtained with the main methods for the extraction of carotenoids and fatty acids in H. pluvialis , in contrast to the proposed method, shows a positive feasibility of this approach.
... Astaxanthin has attracted attention due to its strong antioxidant properties, and there have been many reports focusing on its antioxidant activity. Astaxanthin has been shown to protect various cells from oxidative stress in vitro [31][32][33][34] and to protect the brain, eyes, salivary glands, skeletal muscle, liver, kidney, and lungs from oxidative stress in vivo [12][13][14][15][16][17][35][36][37][38][39]. These results indicate that astaxanthin is distributed throughout the body and has systemic effects. ...
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Oxidative stress plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). The activation of nuclear factor erythroid 2-related factor 2 (Nrf2) is a key cellular defense mechanism against oxidative stress. Recent studies have shown that astaxanthin protects against oxidative stress via Nrf2. In this study, we investigated the emphysema suppression effect of astaxanthin via Nrf2 in mice. Mice were divided into four groups: control, smoking, astaxanthin, and astaxanthin + smoking. The mice in the smoking and astaxanthin + smoking groups were exposed to cigarette smoke for 12 weeks, and the mice in the astaxanthin and astaxanthin + smoking groups were fed a diet containing astaxanthin. Significantly increased expression levels of Nrf2 and its target gene, heme oxygenase-1 (HO-1), were found in the lung homogenates of astaxanthin-fed mice. The number of inflammatory cells in the bronchoalveolar lavage fluid (BALF) was significantly decreased, and emphysema was significantly suppressed. In conclusion, astaxanthin protects against oxidative stress via Nrf2 and ameliorates cigarette smoke-induced emphysema. Therapy with astaxanthin directed toward activating the Nrf2 pathway has the potential to be a novel preventive and therapeutic strategy for COPD.
... The clearly stronger radical scavenging effect of the AST containing extract than chemically pure substance may result from the synergistic effect of the astaxanthin and the other carotenoid esters present in the algae extract. The mixture of the actives eliminates free radicals more effectively (Régnier et al., 2015). ...
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In the work, the antioxidant activity of astaxanthin (AST) and the influence of the base formulation on the kinetics of AST release were studied. Three stable O/W AST-loaded emulsions, differing in droplet size (12.7 µm (E1), 3.8 µm (E2), 3.2 µm (E3)) and a nanoemulsion (0.13 µm, NE) were prepared. The results confirmed very strong antioxidant activity of AST. The emulsion internal phase droplet size did not significantly affect the AST release. The amount of released AST was respectively: 13.60% (E1), 11.42% (E2), 9.45% (E3), 9.71% (NE). The best fit to experimental data was obtained using the Higuchi model for emulsions and the Korsmeyer-Peppas model for NE. The results show that the AST release process is limited by the diffusion through carriers and the prepared O/W emulsions can be applied as vehicles for delivery of astaxanthin to the skin, ensuring effective anti-aging action of the cosmetics.
... Another study evaluated the astaxanthin nanoparticle anticancer potential against MDA-MB-231, revealing IC 50 = 84 μM [61], while astaxanthin induces cell death in MCF-7 at concentrations of 33 mM [62]. These inconsistencies may be probably due to the synthetic origin of astaxanthin, which revealed 90 fold less potent that natural astaxanthin as demonstrated by Régnier, et al. [63] on human umbilical vein endothelial cells. However, astaxanthin has been recognized as breast cancer chemopreventive agent, [62], on the other hand, astaxanthin does not present toxicity on normal breast epithelial cells [64]. ...
Article
During the latest decades, the interest on the effectiveness of natural compounds and their impact on human health constantly increased, especially on those demonstrating to be effective on cancer. Molecules coming from nature are currently used in chemotherapy like Taxol, Vincristine or Vinblastine, and several other natural substances have been showed to be active in reducing cancer cell progression and migration. Among them, astaxanthin, a xanthophyll red colored carotenoid, displayed different biological activities including, antinflammatory, antioxidant, proapoptotic, and anticancer effects. It can induce apoptosis through downregulation of antiapoptotic protein (Bcl-2, p-Bad, and survivin) expression and upregulation of proapoptotic ones (Bax/Bad and PARP). Thanks to these mechanisms, it can exert anticancer effects towards colorectal cancer, melanoma, or gastric carcinoma cell lines. Moreover, it possesses antiproliferative activity in many experimental models and enhances the effectiveness of conventional chemotherapic drugs on tumor cells underling its potential future use. This review provides an overview of the current knowledge on the anticancer potential of astaxanthin by modulating several molecular targets. While it has been clearly demonstrated its multitarget activity in the prevention and regression of malignant cells in in vitro or in preclinical investigations, further clinical studies are needed to assess its real potential as anticancer in humans.
... So, it is important to increase the number of exogenous antioxidants to avoid the harmful effects of free radicals (16). One of the antioxidants that are known to have a reasonably strong effect is astaxanthin (17,18). Astaxanthin, produced from Haematococcus pluvalis, is the most powerful and safest carotenoid without pro-oxidant effects, comparable to beta-carotene, lycopene, zeaxanthin, and lutein. ...
Article
Background: Malondialdehyde (MDA) is a dialdehyde substance that is the final product of lipids peroxidation in the human body, and it can be used as a biomarker of oxidative stress. One of the most potent antioxidants known nowadays is astaxanthin. This study aims to investigate the effect of astaxanthin on the MDA level in cerebral cortex tissue of Rattus norvegicus, which was given oral formaldehyde.
... Haematococcus pluvialis, synthetic astaxanthin ABTS, ORAC, CAA Trolox The extracts were obtained by solvent using DMSO or supercritical extraction (AstaCO2). [311] astaxanthin ORAC-EPR - ...
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Natural extracts are the source of many antioxidant substances. They have proven useful not only as supplements preventing diseases caused by oxidative stress and food additives preventing oxidation but also as system components for the production of metallic nanoparticles by the so-called green synthesis. This is important given the drastically increased demand for nanomaterials in biomedical fields. The source of ecological technology for producing nanoparticles can be plants or microorganisms (yeast, algae, cyanobacteria, fungi, and bacteria). This review presents recently published research on the green synthesis of nanoparticles. The conditions of biosynthesis and possible mechanisms of nanoparticle formation with the participation of bacteria are presented. The potential of natural extracts for biogenic synthesis depends on the content of reducing substances. The assessment of the antioxidant activity of extracts as multicomponent mixtures is still a challenge for analytical chemistry. There is still no universal test for measuring total antioxidant capacity (TAC). There are many in vitro chemical tests that quantify the antioxidant scavenging activity of free radicals and their ability to chelate metals and that reduce free radical damage. This paper presents the classification of antioxidants and non-enzymatic methods of testing antioxidant capacity in vitro, with particular emphasis on methods based on nanoparticles. Examples of recent studies on the antioxidant activity of natural extracts obtained from different species such as plants, fungi, bacteria, algae, lichens, actinomycetes were collected, giving evaluation methods, reference antiox-idants, and details on the preparation of extracts.
Article
Astaxanthin is a potent natural antioxidant with beneficial bioactivities demonstrated primarily for its free (non-esterified) form. However, its natural producer, the microalgae Haematococcus pluvialis synthesizes astaxanthin mostly in ester forms which have been little valorized so far. Hence, to contribute to the commercial use of astaxanthin esters, a scalable and efficient isolation technology is required. In this study, five astaxanthin monoesters were isolated from H. pluvialis using high performance countercurrent chromatography (HPCCC), where the lower phase of a biphasic solvent system (n-heptane:acetonitrile, ratio 5:5, v/v) was used as a mobile phase. Around 200 mg of biomass extract was subjected to the HPCCC leading to a separation of the target astaxanthin esters. To further increase the process productivity, a multi-injection HPCCC method was developed by combining two elution modes (reverse phase and co-current). In co-current elution mode, both the mobile and stationary phases were pumped simultaneously at flow rates of 3 and 1 mL/min respectively, so that the stationary phase that gets lost during each separation cycle is replenished. In total, five injections of samples (200 mg of extract, each) were achieved. Final purification with high performance liquid chromatography (HPLC) afforded five astaxanthin derivatives esterified with α-linolenic acid (1, 4 mg), linoleic acid (2, 8 mg), palmitic acid (3, 8 mg), oleic acid (4, 12 mg) and stearic acid (5, 1 mg) with purities of 98%, as determined by HPLC analysis. Only compound 4 exhibited a cytotoxic effect against human gastric cancer cells. The present study shows a useful approach for obtaining individual astaxanthin esters from H. pluvialis.
Article
The potential of supramolecular solvents (SUPRAS) is investigated for the extraction of bioactive compounds from coffee cherry pulp, one of the major by-products generated in the coffee industry. SUPRAS made up of hexagonal inverted aggregates of octanoic acid in ethanol:water mixtures provided good extraction yields for bioactives (3.6 ± 0.3 mg caffeine g⁻¹ and 0.9 ± 0.1 mg protocatechuic acid g⁻¹) at a low solvent:sample ratio of 4:1 v/w and under mild operations conditions (5 min extraction at room temperature). SUPRAS-based extraction was optimized and extracts were analyzed to identify the main phenolic and alkaloid compounds. A variety of bioactives were present and extracts showed high antioxidant capacity by different assays (45% for DPPH and 91% for ABTS). Extraction efficiencies with SUPRAS were clearly superior than those obtained with organic solvents commonly used for valorization of coffee residues.
Article
The objective of this study is to characterize effects of autophagy inhibition by 3-methyladenine on astaxanthin and fatty acid accumulation in Haematococcus pluvialis cultivated under high light condition. The present data show that 0.02 mM 3-methyladenine treatment effectively inhibited autophagosome formation but no impact on the cell growth and biomass of H. pluvialis, leading to a large increase in cellular reactive oxygen species (ROS), astaxanthin and fatty acid accumulation as well as palmitic acid enrichment under high light of 700 μmol·m⁻²·s⁻¹. Furthermore, the key genes such as phytoene synthase (PSY), β-carotene ketolase (CRTO), and β-carotene hydroxylase (CRTR-b) in astaxanthin pathway are upregulated significantly whereas the expressions of the lipid-related genes biotin carboxylase (BC) and diacylglycerol acyltransferase (HpDGAT2D) just increased slightly in the 3-methyladenine-treated cells. Astaxanthin accumulation is not perfectly linear with fatty acid biosynthesis in H. pluvialis treated by 3-methyladenine under high light. Overall, autophagy might function importantly in astaxanthin and lipid enrichment in H. pluvialis under stress condition. The findings provide new insights to further investigation on the metabolic regulation in microalgae.
Article
The objective of this study was to evaluate three most common scale-up criteria for Haematococcus pluvialis production from cultivation bottles to 2 and 10 L of stirred tank PBRs. Constant volumetric power input (P/V) was found to be the most suitable criterion for H. pluvialis production. Total carotenoid amount per biomass concentration in 2 L and 10 L stirred tank PBRs were determined to be 4.57 mg/g and 4.77 mg/g, respectively. Antioxidant activity of total carotenoids extracted from H. pluvialis was also higher at constant P/V criterion where 46.91% inhibition rate with a total phenolic content of 11.76 mg gallic acid/L was achieved. Obtained results could be used to expand the bioproduction of H. pluvialis and its extracts in commercial scale.
Article
Astaxanthin is a high-valued ketocarotenoid that is rarely synthesized in higher plants due to their lack of a carotenoid ketolase. Overexpression of a heterologous β-carotene ketolase gene coupled with other pathway genes in higher plants has triggered the production of various ketocarotenoids in the transformants. Here we reported that constitutive and simultaneous overexpression of four genes involved in astaxanthin biosynthesis in Brassica napus resulted in the accumulation of the nonnative ketocarotenoids such as astaxanthin and ketolutein, and the decreased production of chlorophylls, lutein and violaxanthin in leaves. As a result, transgenic plants showed lower non-photochemical quenching (NPQ) under high light, leading to moderate photoinhibition of photosystem II (PSII). Such PSII photoinhibition depressed linear electron transport and thus restricted the rate of CO2 assimilation. Consequently, transgenic plants grew slower and showed less biomass than wild type. These results indicated that endogenous synthesis of ketocarotenoids negatively affected photosynthesis and impaired plant growth in B. napus. Therefore, to prevent the side effect on normal growth, seed specific expression of the transgenes may be necessary for enhanced production of astaxanthin in seeds.
Article
Haematococcus pluvialis (H. pluvialis) microalgae are well known for their high content of astaxanthin, which is a super potent antioxidant with various remedial effects. Ionic liquids (ILs) have been proposed as a promising solvent to permeabilize the robust microalgal cell wall for an effective extraction of bioactive compounds. Nonetheless, the removal of ILs from the extracted compounds requires the additional treatment steps that complicate the overall extraction process and the recycling of ILs. To address these shortcomings, we demonstrated a sustainable extraction system that utilizes CO2-based alkyl carbamate ILs to permeate H. pluvialis cells and extract astaxanthin. This class of ILs is readily distillable for an easy recovery of ILs from the extraction medium. Among the tested CO2-based alkyl carbamate ILs [dimethylammonium dimethylcarbamate (DIMCARB), dipropylammonium dipropylcarbamate (DPCARB), dibutylammonium dibutylcarbamate (DBCARB) and diallyammonium diallycarbamate (DACARB)], DIMCARB gave the best performance of astaxanthin extraction. The optimized extraction conditions [100% (w/w) of DIMCARB, 75 min and 45°C] resulted in the high yield of astaxanthin (27.99 mg/g). The capability of DIMCARB to permeabilize the amorphous trilayered structure of cell wall was verified by the presence of pores on the cell surface of H. pluvialis as shown in the microscope images. The performance and recyclability of DIMCARB extraction system were also evaluated by conducting three successive rounds of astaxanthin extraction with the recycled DIMCARB solutions. In addition, the antioxidant capacity of the extracted astaxanthin was well retained, showing that this type of distillable IL was suitable for the extraction of phytonutrients from algal source.
Chapter
Carotenoids possess strong anti-inflammatory and antioxidant actions in addition to a plethora of other properties. These actions of carotenoids are primarily due to their structure which dictate their functions. Because of their protective potential in disease states, carotenoids are associated with prevention and/or treatment of various neurological diseases. In this chapter, the role(s) of carotenoids in various neurological diseases such as Alzheimer’s disease, vascular dementia, Lewy body dementia, mild cognitive impairment, neurological trauma, brain tumor, schizophrenia, depression, Parkinson’s disease and multiple sclerosis, have been reviewed. A number of studies report associations of low levels of carotenoids with higher likelihood of neurological diseases. Other investigations describe beneficial and protective effects of pharmacological or dietary interventions which lead to enhancement of carotenoids levels in the body. However, further validation of these beneficial actions is required both in clinical and animal studies. Development of good animal models of neurological diseases will help.
Chapter
Carotenoids comprise more than 700 naturally occurring pigments principally produced by plants, animals, and microbes for fulfilling their vital physiological actions. Carotenoids have been regarded to be the essential for restoring good health and their absence may lead to chronic health problems. Carotenoids exhibit promising antioxidant activity due to their triplet energy levels and electron-enriched polyene chains. Astaxanthin possesses the highest antioxidant potential among the carotenoid members. However, other members, such as β-carotene, zeaxanthin, fucoxanthin, canthaxanthin, lycopene, phytoene, phytofluene, lutein, violaxanthin, bixin etc. can also exhibit significant antioxidant activity. In addition, carotenoids have been regarded to suppress the risk of development and progression of several ailments, such as cancer, skin problems, eye problems, diabetes, and coronary artery disease via antioxidant mechanism. This chapter emphasizes the detail insight of redox defence mechanism of carotenoids along with their prophylactic roles against disease-provoked oxidative stress.
Chapter
Today the desire for a healthy, youthful appearance combined with the awareness of organic and natural skin care products has led a greater demand for natural active ingredients that possess cosmeceutical properties. Astaxanthin is one of the main carotenoid pigments found in marine resources that represents an interesting source of active ingredient for the cosmetic industry. Astaxanthin isolated from marine resources, including algae (macro- and micro-), crustacean, and salmon, has been confirmed to have a diverse function in skin biology, such as inhibition of oxidative stress, photoprotection, antiaging, and antiinflammatory activities. Due to its beneficial effects on skin health, astaxanthin has been widely used as a constitutional ingredient in cosmetics. This chapter discusses the production and cosmeceutical properties of astaxanthin. In addition, commercial personal care products of astaxanthin were also highlighted.
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Background. Astaxanthin (AX) has been consumed as a nutritional supplement for approximately 20 years. The primary source has been a natural plant-based supplement from the single-cell alga Haematococcus pluvialis (NAT-AX). Recently, astaxanthin from other sources has entered the marketplace. The primary alternative source in the human nutritional supplement market has been a synthetic form of astaxanthin produced from petrochemicals (SYN-AX). In addition, a very small amount of astaxanthin from a genetically manipulated yeast Xanthophyllomyces dendrorhous (former nomenclature Phaffia rhodozyma, still commonly referred to as “Phaffia”) (pH-AX) is also available in some supplement products. The three forms have substantial chemical differences. In addition to the chemical differences between sources of AX, in vitro research has demonstrated profound differences in antioxidant strength, and animal research has revealed fundamental differences in health benefits. In all cases, NAT-AX has proven more biologically active than the other sources. This review is designed to assist readers in understanding which form(s) of AX are suitable for consumers desiring preventive or therapeutic health benefits. Results. In head-to-head antioxidant experiments, NAT-AX demonstrated 14 × to 90 × greater antioxidant activity than SYN-AX. In numerous animal trials in diverse species, NAT-AX in esterified form has demonstrated superior efficacy in increasing lifespan, treating skin cancer, preventing the formation of gastric ulcers, improving resistance to stress, decreasing reactive oxygen species (ROS), increasing retinol conversion in the liver, augmenting enzyme levels, increasing growth rates, and improving exercise endurance. From a human research perspective, NAT-AX has been the subject of more than 100 clinical trials demonstrating safety and a wide variety of health benefits. SYN-AX and PH-AX have not been proven safe for direct human consumption and have not demonstrated any health benefits in clinical trials. Due to these facts, SYN-AX and PH-AX have not been allowed for human consumption by government regulators in many countries, while NAT-AX is widely accepted in most countries around the world. Conclusion. Based on our review of the literature in the succeeding text, we recommend NAT-AX as the sole form of AX for human consumption until SYN-AX and PH-AX have been proven safe and efficacious through human clinical research.
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Phyco-remediation of dyestuffs in textile wastewaters is of economic, industrial, and environmental importance. We evaluated the remediation of the textile dye, Direct Green 6 (DG6), by Spirulina platensis, and investigated the novel possibility that DG6 treatment enhances production of the biopolymer, polyhydroxybutyrate (PHB). We showed that both live and dead cells of Spirulina were capable of DG6 remediation, but live cells could be re-used with no loss of remediation efficiency. Furthermore, DG6 remediation by live cells resulted in increased algal biomass and trichome lengths, and stimulated production of valuable metabolites, including PHB, antioxidants, carbohydrates and pigments (phycobilins and astaxanthin). We determined the optimal conditions for DG6 remediation and an artificial neural network (ANN) accurately modeled the experimental data and predicted the concentration of dye as the most and algal turbidity as the least important parameters for DG6 removal efficiency. A DG6 concentration of 60 mg L-1 resulted in the highest simultaneous co-production of PHB (12.7±1.7% DW) and increase of astaxanthin (194%), carotenoids (50%), phenol (51%), carbohydrates (27%) total phycobilin (43%), together with the enhancement of biomass and trichome lengths (95%). Oxidative stress indices and enzyme activities such as peroxidases and laccase (involved in dye removal/antioxidant functions) were also increased by dye dosage. On the basis of our results, we propose that S. platensis may use DG6 dye as a nitrogen/carbon source for co-accumulation of valuable bioplastic and metabolites.
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Astaxanthin (AXT) is one of the most important fat soluble carotenoids that have abundant and diverse therapeutic applications namely in liver disease, cardiovascular disease, cancer treatment, protection of the nervous system, protection of the skin and eyes against UV radiation, and boosting the immune system. However, due to its intrinsic reactivity, it is chemically unstable, and therefore, the design and production processes of this compound need to be precisely formulated. Nanoencapsulation is widely applied to protect AXT against degradation during digestion and storage, thus improving its physicochemical properties and therapeutic effects. Nanocarriers are delivery systems with many advantages ease of surface modification, biocompatibility, and targeted drug delivery and release. This review discusses the technological advancement in nanocarriers for the delivery of AXT through the brain, eyes, and skin, with emphasis on the benefits, limitations, and efficiency in practice.
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Abstract The qualified presumption of safety (QPS) approach was developed to provide a generic pre‐evaluation of the safety of biological agents. The QPS approach is based on an assessment of published data for each agent, with respect to its taxonomic identity, the body of relevant knowledge and safety concerns. Safety concerns are, where possible, confirmed at the species/strain or product level and reflected by ‘qualifications’. The QPS list was updated in relation to the revised taxonomy of the genus Bacillus, to synonyms of yeast species and for the qualifications ‘absence of resistance to antimycotics’ and ‘only for production purposes’. Lactobacillus cellobiosus has been reclassified as Limosilactobacillus fermentum. In the period covered by this statement, no new information was found that would change the status of previously recommended QPS taxonomic units (TU)s. Of the 70 microorganisms notified to EFSA, 64 were not evaluated: 11 filamentous fungi, one oomycete, one Clostridium butyricum, one Enterococcus faecium, five Escherichia coli, one Streptomyces sp., one Bacillus nakamurai and 43 TUs that already had a QPS status. Six notifications, corresponding to six TUs were evaluated: Paenibacillus lentus was reassessed because an update was requested for the current mandate. Enterococcus lactis synonym Enterococcus xinjiangensis, Aurantiochytrium mangrovei synonym Schizochytrium mangrovei, Schizochytrium aggregatum, Chlamydomonas reinhardtii synonym Chlamydomonas smithii and Haematococcus lacustris synonym Haematococcus pluvialis were assessed for the first time. The following TUs were not recommended for QPS status: P. lentus due to a limited body of knowledge, E. lactis synonym E. xinjiangensis due to potential safety concerns, A. mangrovei synonym S. mangrovei, S. aggregatum and C. reinhardtii synonym C. smithii, due to lack of a body of knowledge on its occurrence in the food and feed chain. H. lacustris synonym H. pluvialis is recommended for QPS status with the qualification ‘for production purposes only’.
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References of all chapters from the book: Therapeutic and Nutritional Use of Algae
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Synthetic astaxanthin (S-AX) was tested against natural astaxanthin from Haematococcus pluvialis microalgae (N-AX) for antioxidant activity. In vitro studies conducted at Creighton University and Brunswick Laboratories showed N-AX to be over 50 times stronger than S-AX in singlet oxygen quenching and approximately 20 times stronger in free radical elimination. N-AX has been widely used over the last 15 years as a human nutraceutical supplement after extensive safety data and several health benefits were established. S-AX, which is synthesised from petrochemicals, has been used as a feed ingredient, primarily to pigment the flesh of salmonids. S-AX has never been demonstrated to be safe for use as a human nutraceutical supplement and has not been tested for health benefits in humans. Due to safety concerns with the use of synthetic forms of other carotenoids such as canthaxanthin and beta-carotene in humans, the authors recommend against the use of S-AX as a human nutraceutical supplement until extensive, long-term safety parameters have been established and human clinical trials have been conducted showing potential health benefits. Additionally, differences in various other properties between SAX and N-AX such as stereochemistry, esterification and the presence of supporting naturally occurring carotenoids in N-AX are discussed, all of which elicit further questions as to the safety and potential health benefits of S-AX. Ultimately, should S-AX prove safe for direct human consumption, dosage levels roughly 20–30 times greater than N-AX should be used as a result of the extreme difference in antioxidant activity between the two forms.
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Microalgae represent diverse branch of microorganism that can produce a wide range of unique functional ingredients that can be used in food, cosmetics, pharmaceuticals, and energy. Among them, Haematococcus pluvialis is known for accumulating the highest levels of a potent natural antioxidant, astaxanthin, which has demonstrated positive health effects. Therefore, the aim of numerous studies has been to develop novel and efficient extraction techniques to produce high-quality (purity and antioxidant activity) extracts, while complying with the Green Chemistry Principles. Supercritical CO2 (scCO2) emerges as an alternative to organic solvents because of its high selectivity and bioactivity-preserving qualities. Nevertheless, astaxanthin is a large molecule with low solubility in scCO2 that usually requires long extractions at high pressures. Ethanol has been used as co-solvent to increase astaxanthin solubility in scCO2. In this work, a Box-Behnken experimental design was used to study the effects of operating pressure (20-35 MPa), temperature (40-70 °C), and ethanol content in scCO2 (0-13%, w/w) on the yield, astaxanthin content, and antioxidant activity of H. pluvialis extract. Results showed that ethanol content in CO2 has a more significant effect on all responses than pressure and temperature. These results lead us to investigate the effect of a further increase in ethanol content, up to the region of gas-expanded liquids. We studied the effects of temperature (30-60 °C) and ethanol content (50-70%, w/w) at a fixed pressure (7 MPa) on the same response variables using CO2-expanded ethanol (CXE). Results showed that temperature and ethanol content had a significant influence on astaxanthin yield and antioxidant activity. Also, the overall responses of CXE surpassed scCO2 extractions to match conventional extraction with acetone, maintaining high quality extracts, thus validating the use of this new type of green technology for extraction of high-value compounds.
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There is currently much interest in biological active compounds derived from natural resources, especially compounds that can efficiently act on molecular targets, which are involved in various diseases. Astaxanthin (3,3'-dihydroxy-β, β'-carotene-4,4'-dione) is a xanthophyll carotenoid, contained in Haematococcus pluvialis, Chlorella zofingiensis, Chlorococcum, and Phaffia rhodozyma. It accumulates up to 3.8% on the dry weight basis in H. pluvialis. Our recent published data on astaxanthin extraction, analysis, stability studies, and its biological activities results were added to this review paper. Based on our results and current literature, astaxanthin showed potential biological activity in in vitro and in vivo models. These studies emphasize the influence of astaxanthin and its beneficial effects on the metabolism in animals and humans. Bioavailability of astaxanthin in animals was enhanced after feeding Haematococcus biomass as a source of astaxanthin. Astaxanthin, used as a nutritional supplement, antioxidant and anticancer agent, prevents diabetes, cardiovascular diseases, and neurodegenerative disorders, and also stimulates immunization. Astaxanthin products are used for commercial applications in the dosage forms as tablets, capsules, syrups, oils, soft gels, creams, biomass and granulated powders. Astaxanthin patent applications are available in food, feed and nutraceutical applications. The current review provides up-to-date information on astaxanthin sources, extraction, analysis, stability, biological activities, health benefits and special attention paid to its commercial applications.
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The objective of this study was to determine chemiluminescence (CL) antioxidant activities and neuroprotective effects of astaxanthin, beta-carotene (β-carotene), and canthaxanthin on undifferentiated rat pheochromocytoma (PC12) cells. We performed three CL antioxidant assays, and the three carotenoids showed varying degrees of antioxidant activity, with astaxanthin exhibiting the highest antioxidant activity than the other two samples. Results of a pyrogallol-luminol assay revealed β-carotene to have higher antioxidant activity than canthaxanthin, whereas cupric sulfate-Phen-Vc-hydrogen peroxide (H2O2) assay showed canthaxanthin to have higher antioxidant activity than β-carotene. Luminol-H2O2 assay showed the antioxidant activity series as canthaxanthin > β-carotene at 62.5-1000 μg/mL and β-carotene > canthaxanthin at 1000-4000 μg/mL. Astaxanthin exhibited partial neuroprotective activity against H2O2 and the strongest neuroprotective activity against amyloid beta-peptide(25-35) [(Aβ)(25-35)]-induced undifferentiated PC12 cell deaths at 0.5-5.0 μM. Canthaxanthin showed partial neuroprotective activity in Aβ(25-35)-induced undifferentiated PC12 cell deaths at 1.0-5.0 μM. Astaxanthin protected undifferentiated PC12 cells from the damaging effects of H2O2 and Aβ(25-35) by the following ways: (1) scavenging superoxide anion radicals, hydroxyl radicals, and H2O2; (2) securing cell viability; (3) suppressing the production of reactive oxygen species; and (4) eliminating calcium ion influx. Our results conclusively show that astaxanthin has the merit as a potential neuron protectant.
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Antioxidants are the chemical substances that reduce or prevent oxidation. The present study aimed to assess in vitro and ex vivo antioxidant activities of four acetonic extracts Tunisian halophytes (Suaeda fruticosa, Suaeda pruinosa, Suaeda mollis and Suaeda maritima). Various experimental models were used for characterization of antioxidant activities of shoot extracts. Eventually, the promising specie was subjected to phenolic identification using RP-HPLC. The analyzed shoot extracts exhibited that antioxidant activities varied considerably as function of species. The highest DPPH scavenging ability was found in S. mollis with the lowest IC50 value (2.5μg/ml), followed by S. pruinosa, S. fruticosa and S. maritima. The same tendency was observed with ferric reducing power. Concerning β-carotene bleaching assays and total antioxidant activity, results showed that S. fruticosa exhibited the highest antioxidant ability against the inhibition of β-carotene bleaching, and a better total antioxidant capacity. Moreover antioxidant capacities using ORAC method and a cell based-assay showed that S. mollis, S. fruticosa, and S. pruinosa exhibit statistically similar antioxidant activity. The identification of phenolic compounds in S. mollis extract using RP-HPLC revealed that 2,5-dihydroxybenzoic acid and rutin hydrate were the major molecules. These results suggested that Suaeda species showed a variability of their antioxidant activities.
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Astaxanthin, one of the dominant carotenoids in marine animals, showed both a strong quenching effect against singlet oxygen, and a strong scavenging effect against free radicals. These effects are considered to be defence mechanisms in the animals for attacking these active oxygen species. The activities of astaxanthin are approximately 10 times stronger than those of other carotenoids that were tested, namely zeaxanthin, lutein, tunaxanthin, canthaxanthin and β-carotene, and 100 times greater than those of a tocopherol. Astaxanthin also showed strong activity as an inhibitor of lipid peroxidation mediated by these active forms of oxygen. From these results, astaxanthin has the properties of a “SUPER VITAMIN E”.
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Oxidative stress and inflammation are established processes contributing to cardiovascular disease caused by atherosclerosis. However, antioxidant therapies tested in cardiovascular disease such as vitamin E, C and β-carotene have proved unsuccessful at reducing cardiovascular events and mortality. Although these outcomes may reflect limitations in trial design, new, more potent antioxidant therapies are being pursued. Astaxanthin, a carotenoid found in microalgae, fungi, complex plants, seafood, flamingos and quail is one such agent. It has antioxidant and anti-inflammatory effects. Limited, short duration and small sample size studies have assessed the effects of astaxanthin on oxidative stress and inflammation biomarkers and have investigated bioavailability and safety. So far no significant adverse events have been observed and biomarkers of oxidative stress and inflammation are attenuated with astaxanthin supplementation. Experimental investigations in a range of species using a cardiac ischaemia-reperfusion model demonstrated cardiac muscle preservation when astaxanthin is administered either orally or intravenously prior to the induction of ischaemia. Human clinical cardiovascular studies using astaxanthin therapy have not yet been reported. On the basis of the promising results of experimental cardiovascular studies and the physicochemical and antioxidant properties and safety profile of astaxanthin, clinical trials should be undertaken.
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In Taiwan, Toona sinensis (Toona sinensis) is well known as a traditional Chinese medicine, while the underlying pharmacological mechanisms of this drug are still a matter of debate. The purpose of this study was to evaluate the protective effects of non-cytotoxic concentrations of aqueous leaf extracts of Toona sinensis (TS extracts; 50-100 μg/mL) and gallic acid (5 μg/mL), a major component of these extracts, against AAPH-induced oxidative cell damage in human umbilical vein endothelial cells (ECs). Exposure of ECs to AAPH (15 mM) decreased cell viability from 100% to 43%. However, ECs were pre-incubated with TS extracts prior to AAPH induction resulted in increased resistance to oxidative stress and cell viability in a dose-dependent manner. An increase in ECs-derived PGI(2) and IL-1 β in response to AAPH exposure was positively correlated with cytotoxicity and negatively with TS extracts concentrations. In addition, gallic acid also suppressed PGI(2) and IL-1 β production in AAPH-induced ECs. Notably, TS extracts/gallic acid treatment significantly inhibited ROS generation, MDA formation, SOD/catalase activity, and Bax/Bcl-2 dysregulation in AAPH-stimulated ECs. Pretreatment of ECs with TS extracts/gallic acid also suppressed AAPH-induced cell surface expression and secretion of VCAM-1, ICAM-1 and E-selectin, which was associated with abridged adhesion of U937 leukocytes to ECs. Moreover, TS extracts/gallic acid treatment significantly inhibited the AAPH-mediated up regulation of PAI-1 and down regulation of t-PA in ECs, which may decrease fibrinolytic activity. Therefore, Toona sinensis may possess antioxidant properties that protect endothelial cells from oxidative stress. Our results also support the traditional use of Toona sinensis in the treatment of free radical-related diseases and atherosclerosis.
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Astaxanthin is a xanthophyll carotenoid present in microalgae, fungi, complex plants, seafood, flamingos and quail. It is an antioxidant with anti-inflammatory properties and as such has potential as a therapeutic agent in atherosclerotic cardiovascular disease. Synthetic forms of astaxanthin have been manufactured. The safety, bioavailability and effects of astaxanthin on oxidative stress and inflammation that have relevance to the pathophysiology of atherosclerotic cardiovascular disease, have been assessed in a small number of clinical studies. No adverse events have been reported and there is evidence of a reduction in biomarkers of oxidative stress and inflammation with astaxanthin administration. Experimental studies in several species using an ischaemia-reperfusion myocardial model demonstrated that astaxanthin protects the myocardium when administered both orally or intravenously prior to the induction of the ischaemic event. At this stage we do not know whether astaxanthin is of benefit when administered after a cardiovascular event and no clinical cardiovascular studies in humans have been completed and/or reported. Cardiovascular clinical trials are warranted based on the physicochemical and antioxidant properties, the safety profile and preliminary experimental cardiovascular studies of astaxanthin.
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Several glycosaminoglycans (GAGs) have been demonstrated to protect the ischemic heart against reperfusion injury, in part, by modulating activation of the complement cascade. The present study assessed the cardioprotective effects of sulodexide (KRX-101), a mixture of GAGs composed of 80% low-molecular mass heparin and 20% dermatan sulfate. KRX-101 differs from other GAGs (e.g., heparin) in that it has limited anticoagulant efficacy and can be administered orally. The experimental protocol was designed to determine whether KRX-101 could protect the ischemic myocardium. Anesthetized New Zealand white rabbits underwent 30 min of coronary artery occlusion. Intravenous doses of KRX-101 (0.5 mg/kg, n = 10) or drug diluent (n = 10) were administered at the end of regional ischemia and at each hour of reperfusion. Infarct size, as a percentage of the area at risk, was calculated for both groups. Myocardial infarct size was 31.3 +/- 4.1% in the vehicle- and 17.3 +/- 3.2% in the KRX-101-treated animals (p < 0.05 versus vehicle). Activated partial thromboplastin times determined at baseline (preischemia) and at each hour of reperfusion (n = 4) were not significantly different between vehicle- and KRX-101-treated groups (p = N.S.). Myocardial injury was further assessed by measuring serum levels of cardiac-specific troponin I. KRX-101 administration significantly reduced (p < 0.05) the serum concentration of troponin I during reperfusion. The results suggest that KRX-101 may be an effective adjunctive agent in myocardial revascularization procedures, without the risk of increased bleeding.
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Accumulating evidence suggests that peroxisome proliferator-activated receptor (PPAR) agonists possess powerful antiatherosclerotic properties, by both directly affecting the vascular wall and indirectly affecting systemic inflammation and insulin sensitivity. The PPARs are ligand-activated transcription factors, which play a number of important physiological roles in lipid and glucose homeostasis. Activation of PPARgamma appears to exert a vasculoprotective effect by limiting endothelial dysfunction, impairing atherogenesis and preventing restenosis, while simultaneously and favourably modulating adipokine expression and lipid metabolism. Several experimental and clinical studies have demonstrated the potential of the PPAR agonist drug class in terms of treating atherosclerotic disease. In the present review, the vascular biology of PPARs, and how the modulation of these molecular pathways may serve as a therapeutic strategy to prevent atherosclerosis, vascular inflammation and restenosis are discussed.
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The activity of antioxidants in foods and biological systems is dependent on a multitude of factors, including the colloidal properties of the substrates, the conditions and stages of oxidation and the localisation of antioxidants in different phases. When testing natural antioxidants in vitro, it is therefore important to consider the system composition, the type of oxidisable substrate, the mode of accelerating oxidation, the methods to assess oxidation and how to quantify antioxidant activity. Antioxidant effectiveness is also determined by the heterogeneity and heterophasic nature of the system, the type of lipid substrate, including its physicochemical state and degree of unsaturation, the types of initiators, notably transition metals, other components and their possible interaction. For this reason there cannot be a short‐cut approach to determining antioxidant activity. Each evaluation should be carried out under various conditions of oxidation, using several methods to measure different products of oxidation. Because most natural antioxidants and phytochemicals are multifunctional, a reliable antioxidant protocol requires the measurement of more than one property relevant to either foods or biological systems. Several recent studies on natural phytochemical compounds produced conflicting results because non‐specific one‐dimensional methods were used to evaluate antioxidant activity. There is a great need to standardise antioxidant testing to minimise the present chaos in the methodologies used to evaluate antioxidants. Several methods that are more specific should be used to obtain chemical information that can be related directly to oxidative deterioration of food and biological systems. © 2000 Society of Chemical Industry
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To investigate the efficacy of astaxanthin from unicellular green alga, Haematococcus pluvialis inhibited the cell growth and trigger the apoptosis in human hepatoma cancer cell line (HepG2) in a dose and time dependent manner. Cell viability was analyzed by 3-(4, 5-dimethylthiazol2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) assay. The different concentration of astaxanthin viz. 5, 10, 15, 20 and 25 μg/mL to incubate the cell lines at different time course. The lactate dehydrogenase leakage (LDH) content and reduced glutathione (GSH) levels were also estimated. The depletion of GSH may be involved in the induction of apoptosis of the cancer cells. The apoptosis was evaluated with Annexin-V and Propidium iodide under fluorescent microscopy study. Moreover, the efficacy of astaxanthin 25 μg/mL significantly inhibits the hepatoma cancer cell growth and induces cell apoptosis. In addition, immunofluorescence staining and flow cytometry studies were revealed that further evidence to confirm that the astaxanthin 15 and 25 μg/mL to trigger the apoptosis 42.55% and 58.55% for 24 h, respectively. Taken together, the present study suggests that H. pluvialis astaxanthin may protect from liver cancer.
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The advanced lesions of atherosclerosis represent the culmination of a specialized form of chronic inflammation followed by a fibroproliferative process that takes place within the intima of the affected artery. Proliferation of smooth muscle cells and generation of connective tissue occur. Proliferation results from interactions between arterial smooth muscle, monocyte-derived macrophages, T lymphocytes, and endothelium. The initial lesion of atherosclerosis, the fatty streak, begins as an accumulation of monocytederived macrophages and T lymphocytes, which adhere and migrate into the intima of the affected artery. Smooth muscle cells, which are present in the intima or which migrate into the intima from the media, then replicate. Monocyte-derived macrophages and T cells also replicate during lesion formation and progression due to the production of cytokines and growth-regulatory molecules. These molecules determine whether there is proliferation and lesion progression or inhibition of proliferation and lesion regression. Several growthregulatory molecules may play critical roles in this process, including platelet-derived growth factor (PGDF), transforming growth factor beta, fibroblast growth factor, heparinbinding epidermal growth factor-like growth factor, and others. PDGF may be one of the principal components in this process because protein containing the PDGF B-chain has been demonstrated within activated lesion macrophages during every phase of atherogenesis. The presence of this growth factor and its receptors on lesion smooth muscle cells creates opportunities for smooth muscle chemotaxis and replication. Smooth muscle proliferation depends upon a series of complex signals based upon cellular interactions in the local microenvironment of the artery. The intracellular signalling pathways for mitogenesis versus chemotaxis are being investigated for smooth muscle. The roles of the cytokines and growth-regulatory peptides involved in these cellular interactions represent critical points of departure for intervention and the development of new diagnostic methods. In addition, magnetic resonance imaging has been developed to demonstrate the fine structure of lesions of atherosclerosis in peripheral arteries not subject to cardiac motion. This noninvasive methodology holds great promise for the future of these approaches.
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Oxidative stress greatly influences the pathogenesis of various cardiovascular disorders. Coronary interventions, including balloon angioplasty and coronary stent implantation, are associated with increased vascular levels of reactive oxygen species in conjunction with altered endothelial and smooth muscle cells function. These alterations potentially lead to restenosis, thrombosis, or endothelial dysfunction in the treated artery. Therefore, the understanding of the pathophysiological role of reactive oxygen species generated during and/or after coronary interventions is essential to improve the success rate of these procedures. Superoxide anions, whether derived from uncoupled endothelial nitric oxide synthase, NADPH oxidase, xanthine oxidase or mitochondria, are among the most harmful reactive oxygen species. Superoxide can scavenge nitric oxide, modify proteins and nucleotides, and induce pro-inflammatory signaling, which may lead to a greater reactive oxygen species production. Current innovations in stent technologies, including biodegradable stents, nitric oxide donor-coated stents, and a new generation of drug-eluting stents, therefore, address persistent oxidative stress and reduced nitric oxide bioavailability after percutaneous coronary interventions. This review discusses the molecular mechanisms of reactive oxygen species generation after coronary interventions, the related pathological events, including restenosis, endothelial dysfunction, and stent thrombosis, and possible therapeutic ways forward.
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The mechanism of the effect of tert-butyl hydroperoxide (tBHP) on the kinetics of decrease in liver mitochondrial ΔΨ (transmembrane electric potential) in response to successive additions of tBHP in low concentrations has been studied. FeSO(4) was found to increase significantly the damaging effect of tBHP; this effect was shown to increase in the presence of low concentrations of Ca2+ starting from 2 µM CaCl(2). Cyclosporin A prevents these effects. The data show that the damaging effect of low concentrations of tBHP in the course of pyruvate oxidation in isolated liver mitochondria is caused by the opening of the nonspecific Ca2+-dependent cyclosporin A-sensitive pore in the inner mitochondrial membrane. Application of a method of studying oxidative stress regulators, developed in this work, is illustrated by an example of the prooxidant action of ascorbate. This method is proposed for studying mitochondria in hemochromatosis, a pathology caused by excessive accumulation of iron.
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Abstract— The spectroscopic (absorption and fluorescence) properties of chloroplast lamellae from wheat leaves, extracted by apolar and progressively polar solvents, show three principal characteristics: (1) When lamellae are extracted by petroleum ether at –20°C, only β-carotene is removed; the difference (chloroplast minus residue) absorption spectrum shows a maximum at 510 nm. When the extraction is performed at room temperature, all of the β-carotene and 30 per cent of the lutein are solubilized; the resulting difference absorption spectrum shows two bands in the carotenoid region with maxima at 505 and 495 nm. (2) Petroleum ether, an apolar solvent, and petroleum ether + 0·1% ethanol remove preferentially the long-wavelength forms of chlrorphyll a (710 and 690 nm). In contrast, chlorophyll a 670 nm holochrome is in a more polar environment; indeed, it is removed only by acetone-water (80:20, v/v). (3) The emission spectrum of lamellae extracted by petroleum ether + 1·0% ethanol shows that one of the main chlorophyll a holochromes of such extracted lamellae has, at 77K, an emission maximum at 695 nm, the same as the chlorophyll aII reaction center. Excitation spectra of fluorescence corroborate the maxima observed in absorption spectra. The different types of chlorophyll previously described after binding and labelling studies are spectroscopically identified: Type I may correspond to long-wavelength chlorophyll a holochromes; Type III may include at least the chlorophyll a 670 holochrome. L‘étude des propriétés spectroscopiques (absorption et fluorescence) des lamelles chloroplastiques de feuilles de blé, extraites par des solvants apolaires et progressivement polaires, conduit à trois principaux résultats: (1) Quand les lamelles sont traitées par l’éther de pérole à– 20°C, seul le β-carotène est extrait; le spectre de différence d'absorption (chloroplastes moins résidus) montre un maximum à 510 nm. Quand l'extraction est faite à la température ordinaire, tout le β-carotène et 30 pour cent de la lutéine sont solubilisés; le spectre de différence d'absorption correspondant possède deux bandes dans la région des caroténoïdes avec des maximums à 505 et 495 nm. (2) L‘éther de pétrole, solvant apolaire, et l’éther de petrole +0·1%éthanol enlèvent préférentiellement les formes de chlorophylle a de grande longueur d'onde (710 et 690 nm). A l'opposé, l'holochrome chlorophylle a 670 nm se trouve dans un environnement plus polaire puisqu'on ne l'extrait qu'avec de l'acétone-eau (80:20, v/v). (3) Le spectre d‘émission de fluorescence des lamelles extraites par l’éther de pétrole + 1·0%éthanol montre que l'un des holochromes principaux de ces lamelles a, à 77 K, un maximum d‘émission à 695 nm, semblable à celui du centre réactionnel chlorophylle aII. Les spectres d'excitation de fluorescence confirment les maximums observés sur les spectres d'absorption. Les différents types de chlorophylles décrits précédemment aprés des études de forces de liaison et de vitesses de renouvellement sont identifiés à des formes différentes en spectroscopie in vivo: le Type I peut correspondre aux holochromes de chlorophylle a de grande longueur d'onde; le Type III peut inclure au moins l'holochrome chlorophylle a 670.
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The activity of antioxidants in foods and biological systems is dependent on a multitude of factors, including the colloidal properties of the substrates, the conditions and stages of oxidation and the localisation of antioxidants in different phases. When testing natural antioxidants in vitro, it is therefore important to consider the system composition, the type of oxidisable substrate, the mode of accelerating oxidation, the methods to assess oxidation and how to quantify antioxidant activity. Antioxidant effectiveness is also determined by the heterogeneity and heterophasic nature of the system, the type of lipid substrate, including its physicochemical state and degree of unsaturation, the types of initiators, notably transition metals, other components and their possible interaction. For this reason there cannot be a short-cut approach to determining antioxidant activity. Each evaluation should be carried out under various conditions of oxidation, using several methods to measure different products of oxidation. Because most natural antioxidants and phytochemicals are multifunctional, a reliable antioxidant protocol requires the measurement of more than one property relevant to either foods or biological systems. Several recent studies on natural phytochemical compounds produced conflicting results because non-specific one-dimensional methods were used to evaluate antioxidant activity. There is a great need to standardise antioxidant testing to minimise the present chaos in the methodologies used to evaluate antioxidants. Several methods that are more specific should be used to obtain chemical information that can be related directly to oxidative deterioration of food and biological systems.© 2000 Society of Chemical Industry
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The singlet oxygen quenching activities of carotenoids, -carotene, free astaxanthin, its monoester and its diester, were examined invitro by a simple and rapid method for the measurement of Methylene Blue-sensitized photooxidation of linoleic acid in the hexane/ethanol solvent system. The concentrations of carotenoids, -carotene, free astaxanthin, its mono- and di-ester, required for 50% inhibition of lipid oxidation were 40, 8, 9, and 0M in 100% ethanol and, 14, 16, 10, and 7M in 50% (v/v) hexane in ethanol, respectively. Astaxanthin esters function as powerful antioxidant agents under both hydrophobic and hydrophilic conditions.
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Oxygen radical antioxidant capacity (ORAC) and trolox equivalent antioxidant capacity (TEAC) assays were compared to estimate the total antioxidant capacity (TAC) of orange juice, milk, and an orange juice-milk beverage. When the TEAC method was used with this beverage, an increase in the concentration of orange juice corresponded to an increase in TAC, but increasing the percentage of milk did not increase the TAC value. When the ORAC method was applied, it was seen that increased concentrations of juice or milk corresponded to greater antioxidant capacity. An evaluation was also made of the influence of certain compounds (ascorbic acid, gallic acid, β-carotene, lutein, zeaxanthin and albumin) with antioxidant capacity that were present in the samples studied.Although the TEAC method is simpler and cheaper than the ORAC method, it gives an underestimate of the antioxidant capacity of foods or beverages of a more complex nature.
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In this work, extraction of antioxidant carotenoids from Haematococcus pluvialis microalga, has been studied combining pressurized liquid extraction (PLE), using hexane and ethanol as extracting solvents, and analytical techniques such as thin layer chromatography (TLC) and HPLC with DAD. The effect of the extraction temperature (50, 100, 150 and 200 °C) and the polarity of the solvent have been studied in terms of in vitro antioxidant activity and chemical composition considering two different morphological cells (green vegetative cells and red cysts). Results demonstrate that the extraction temperature had a positive influence in the extraction yield while its effect in the antioxidant activity was negative, lowering the activity of the extracts with an increase of the extraction temperature. The best yields were obtained with ethanol at the higher extraction temperature while the best antioxidant activity was also achieved using ethanol but at lower temperatures. Chemical composition was determined by TLC and HPLC with DAD. Several compounds were identified in the samples and concentration of astaxanthin was obtained. Results pointed out that the extracts contained different carotenoids in both, the green and the red phase, and that depending on its contribution a stronger antioxidant activity would be expected.
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Reactive oxygen species play a critical role in cardiovascular diseases, inflammatory diseases, neurodegenerative disorders, cancer and aging. Diets rich in foods containing antioxidants, such as fruits and vegetables, could help prevent these pathologies. It is therefore important to properly assay the antioxidant potentials of these antioxidant foods in order to have a guideline for their proper use. Actual in vitro methodologies are often very specific for one mode of action and do not necessarily reflect the normal biological context in which they are used. In this work, we have developed a cell-based assay using 2′,7′-dichlorofluorescin-diacetate (DCFH-DA), a useful indicator of reactive oxygen species (ROS), in order to determine the antioxidant properties of foods, extracts and molecules. Results show a dose-dependent antioxidant activity for pure compounds (in decreasing order of activity: quercetin > caffeic acid > gallic acid > α-tocopherol) and fruit juices (in decreasing order of activity: strawberries > highbush blueberries > kiwis > peaches). These results are in good agreement with results obtained using the ORACFL assay. However, the cell-based assay detected a pro-oxidant effect with broccoli and carrot juices which was not observed using the ORACFL assay. Mixed isomers of β,α-carotene isolated from carrots were also found to oxidize DCFH about 212% above control-level. Interestingly, the boiling of broccoli and carrot juices inhibits this pro-oxidant effect and restores the antioxidant properties of the juices. Moreover, the boiling of the β,α-carotene mixed isomers causes their partial degradation and significantly inhibits DCFH oxidation about 68%, suggesting that carotenoids present in broccoli and carrot juices are, in part, responsible for their pro-oxidant effects.
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Many factors have been implicated in the pathophysiology of hypertension such as upregulation of the renin-angiotensin-aldosterone system, activation of the sympathetic nervous system, perturbed G protein-coupled receptor signalling, inflammation, and altered T-cell function. Common to these processes is increased bioavailability of reactive oxygen species (ROS) (termed oxidative stress) due to excess ROS generation, decreased nitric oxide (NO) levels, and reduced antioxidant capacity in the cardiovascular, renal, and nervous systems. Although oxidative stress may not be the sole etiology of hypertension, it amplifies blood pressure elevation in the presence of other prohypertensive factors. In the cardiovascular system ROS play a physiological role in controlling endothelial function, vascular tone, and cardiac function, and a pathophysiological role in inflammation, hypertrophy, proliferation, apoptosis, migration, fibrosis, angiogenesis, and rarefaction, all of which are important processes contributing to endothelial dysfunction and cardiovascular remodelling in hypertension. A major source for cardiovascular ROS is a family of nonphagocytic nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Nox1, Nox2, Nox4, and Nox5). Other sources include mitochondrial enzymes, xanthine oxidase, and uncoupled NO synthase (NOS). Although convincing data from animal studies support a causative role for oxidative stress in the pathogenesis of hypertension, there is still no solid evidence that oxidative stress causes hypertension in humans. However, biomarkers of excess ROS are increased in patients with hypertension and oxidative damage is important in the molecular mechanisms associated with cardiovascular and renal injury in hypertension. Although clinical trials failed to show beneficial antihypertensive effects of antioxidants, strategies that combat oxidative stress by targeting Noxs in an isoform-specific manner may have therapeutic potential.
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Unlabelled: Oxidative stress and inflammation are key promoters of atherosclerosis and myocardial damage. When orally administered, the novel astaxanthin prodrug CDX-085 delivers high levels of the xanthophyll antioxidant astaxanthin that protects LDL from oxidation and reduces primary thrombosis. In this study, we analyzed whether delivery of astaxanthin from administration of the CDX-085 prodrug reduces plasma lipoprotein levels and the progression of atherosclerosis in low-density lipoprotein receptor negative (LDLR(-/-)) and apolipoprotein E deficient (ApoE(-/-)) mice. Methods: Relative circulating levels of astaxanthin derived from CDX-085 administration compared to administration of pure astaxanthin was initially evaluated in a canine model. In mouse Study #1, 16 wild-type and 16 LDLR(-/-) mice on 0.5% cholesterol diet supplemented with either 0.0%, 0.08%, 0.2% and 0.4% CDX-085 were used to assess plasma levels and lipoprotein biodistribution measured by FPLC after 4 weeks treatment. In Study #2, 36 male LDLR(-/-) mice were randomized to a 0.5% cholesterol chow diet (CHOW group, n=12) or 0.5% cholesterol chow fortified with 0.08% CDX-085 (n=12) or 0.5% cholesterol chow with 0.4% CDX-085 (n=12) for 12 weeks. In Study #3, 34 male ApoE(-/-) mice were randomized in the same fashion as the Study #2 and fed similar diets for 9 weeks. Results: CDX-085 administration was shown to result in significantly higher levels of circulating astaxanthin (p<0.001 ANOVA) over a 72 h period compared to pure, non-esterified astaxanthin in a single-dose pharmacokinetic study in beagles. In Study #1, plasma astaxanthin levels were 5-9-fold higher in LDLR(-/-) mice compared to wild-type mice. Astaxanthin was highly distributed among all lipoprotein fractions, generally reflecting cholesterol content of lipoproteins. In Study #2, administration of CDX-085 resulted in significantly lower total cholesterol levels (528±68 mg/dL vs. 550±67 mg/dL vs. 602±80 mg/dL, p=0.047) and aortic arch atherosclerosis (9.0±4.2% vs. 9.8±3.5% vs. 13.2±3.6%, p=0.023) in the 0.4% CDX-085 group compared to the 0