No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Stabilization of collagen by polyphenols[STABILISATION DU COLLAGENE PAR LES OLIGOMERES PROCYANIDOLIQUES]
... Proanthocyanidins (PAs) have the ability to cross-link collagen. Collagen stabilization using procyanidolic oligomers was first reported in 1981 by Masquelier et al. [30]. PAs have the ability to differentially precipitate one protein, while there is an excessive amount of another protein. ...
Polyphenols are micronutrients obtained from diet that have been suggested to play an important role in health. The health benefits of polyphenols and their protective effects in food systems as antioxidant compounds are well known and have been extensively investigated. However, their functional roles as a "processing cofactor" in tissue engineering applications are less widely known. This review focuses on the functionality of polyphenols and their application in biomaterials. Polyphenols have been used to stabilize collagen and to improve its resistance to degradation in biological systems. Therefore, they have been proposed to improve the performance of biomedical devices used in cardiovascular systems by improving the mechanical properties of grafted heart valves, enhancing microcirculation through the relaxation of the arterial walls and improving the capillary blood flow and pressure resistance. Polyphenols have been found to stimulate bone formation, mineralization, as well as the proliferation, differentiation, and the survival of osteoblasts. These effects are brought about by the stimulatory effect of polyphenols on osteoblast cells and their protective effect against oxidative stress and inflammatory cytokines. In addition, polyphenols inhibit the differentiation of the osteoclast cells. Collectively, these actions lead to promote bone formation and to reduce bone resorption, respectively. Moreover, polyphenols can increase the cross-linking of dentine and hence its mechanical stability. Overall, polyphenols provide interesting properties that will stimulate further research in the bioengineering field.
... Denaturation of the molecule, for example by increased temperature or oxidative stress, leads to shortening of the collagen fibers. In vitro, Masquelier's® Original OPCs have been shown to protect against the thermal contraction of the collagen [77]. Of all bioflavonoids only the proanthocyanidins (oligomeric flavanols) seem to exert this protecting effect which might be due to the variation in their cross-linking effect. ...
Careful characterization and standardization of the composition of plant-derived food supplements is essential to establish a cause-effect relationship between the intake of that product and its health effect. In this review we follow a specific grape seed extract containing monomeric and oligomeric flavan-3-ols from its creation by Jack Masquelier in 1947 towards a botanical remedy and nutraceutical with proven health benefits. The preparation's research history parallels the advancing insights in the fields of molecular biology, medicine, plant and nutritional sciences during the last 70 years. Analysis of the extract's flavanol composition emerged from unspecific colorimetric assays to precise high performance liquid chromatography-mass spectrometry and proton nuclear magnetic resonance fingerprinting techniques. The early recognition of the preparation's auspicious effects on the permeability of vascular capillaries directed research to unravel the underlying cellular and molecular mechanisms. Recent clinical data revealed a multitude of favorable alterations in the vasculature upon an 8 weeks supplementation which summed up in a health benefit of the extract in healthy humans. Changes in gene expression of inflammatory pathways in the volunteers' leukocytes were suggested to be involved in this benefit. The historically grown scientific evidence for the preparation's health effects paves the way to further elucidate its metabolic fate and molecular action in humans.
... Moreover, flavanols are known to stimulate the synthesis of amino acids precursors of collagen and elastin. [27][28][29][30][31][32][33][34][35][36][37][38] This action on skin elastic fibers has a direct impact on the vascularization system acting on the capillary resistance. This effect on skin circulation has been observed through the skin color improvement after supplementation as the main pigments responsible for the different hues are melanin, bilirubin, and hemoglobin. ...
Background
Environmental factors impact the skin aging resulting in decrease of skin radiance. Nutrition and particularly antioxidants could help to fight against skin degradation.
Objective
The aim of this study was to evaluate the effects of an oral supplement rich in specific antioxidants, SkinAx2TM, on the improvement of the skin radiance in women.
Methods
The open-label clinical study enrolled 35 women, aged 40–70, with facial dull complexion. Subjects were supplemented orally with a daily dosage of 150 mg of an antioxidant-rich formulation containing superoxide dismutase-rich melon concentrate, grape seed extract rich in monomers of flavanols, vitamin C, and zinc for 8 weeks. Each subject served as her own control. The C.L.B.T.™ test has been used to evaluate facial skin coloring (C), luminosity (L), brightness (B), and transparency (T) involved in skin radiance. Facial skin imperfections have been assessed by clinical assessment. Firmness has been evaluated by clinical assessment and cutometer measurement. Finally, an auto-questionnaire has been carried out in order to evaluate the satisfaction of the subjects concerning different parameters involved in skin radiance and the global efficacy of the supplement.
Results
Skin “red pink” and “olive” colors were significantly improved after supplementation (P<0.0001). Luminosity was increased by 25.9% (P<0.0001) whereas brightness and transparency were not affected by the supplementation. Facial skin imperfections were significantly reduced after the antioxidant-rich formulation intake (global reduction: −18.0%; P<0.0001). Indeed, dark circles, redness, and spots significantly diminished after oral treatment. Firmness and elasticity have been shown to be improved. Subjects were globally satisfied by the product (82.4%) and have found improvements on their facial skin. Furthermore, 64.7% reported to look better at the end of the supplementation.
Conclusion
The oral supplement containing the antioxidant-rich formulation was found to improve skin radiance by reducing skin coloring, increasing face luminosity, reducing imperfections, and improving skin firmness in women with dull complexion.
... Proanthocyanidin (Pycnogenol), a type of flavonoid and antioxidant is found in the skin of fruits and vegetables. It plays an important role in blood vessels, and helps in stabilizing collagen [9,10] and maintenance of elastin [11] within the body. Collagen and elastin are the two principle proteins, which are used in the formation of connective tissue in the body. ...
A case of 15 years old boy, with gynecomastia, absence of secondary sexual characters, low sperm count and low sperm motility on semen analysis is presented. His hormonal profile was normal for age. The patient was prescribed proanthocyanidin 75 mg dosage twice a day and followed up regularly. In the following 5 years, his gynecomastia improved, secondary sexual characters appeared and sperm count normalized. The case is described for the novel indication of proanthocyanidin in treating gynecomastia, oligo-and asthenospermia in the presence of a normal hormonal profile. Its plausible mode of action is debatable.
... Proanthocyanidins (PA) are natural biocompatible CCLs, MMP inhibitors, anti-bacterial and anti-oxidants that interact with proteins to stabilize and increase the Type-I collagen cross-linkage, by promoting hydrogen bond formation between the protein amide carbonyl and the phenolic hydroxyl. Grape seed extracts are a rich source of PA, yielding a 10% higher concentration of PA. [11,12] Proanthocyanidins have shown to improve the resin-dentin bond strength of etch-and-rinse adhesives to both sound dentin and caries-affected dentin. [13,14] Assuming that the infiltration of resins would be facilitated by EWB and the presence of CCLs within the hybrid layer would build the ideal interface resistant to hydrolysis and enzymatic degradation, this study was designed with the aim to evaluate whether the application of two simplified etch-and-rinse adhesives to biomodified dentin using EWB with and without CCL pretreatment improves their sealing ability. ...
To evaluate whether the application of two simplified etch-and-rinse adhesives to biomodified dentin using ethanol-wet bonding (EWB) and collagen cross-linker (CCL) pretreatment improves their sealing ability.
In 176 extracted human molars, the pulp-chambers were deroofed, and teeth were sectioned horizontally. Samples were randomly divided into eight groups according to four bonding techniques using two simplified etch-and-rinse adhesives; Adper Single Bond 2 (ASB) and XP Bond (XPB). The bonding protocols included: (a) Water-wet bonding (WWB); (b) EWB; (c) WWB and CCL application; (d) EWB and CCL application. After composite resin restorations, dye leakage evaluation and scanning electron microscope analysis were done. Leakage scores were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests at a significance level of P < 0.05.
For both ASB and XPB adhesives, least dye leakage was observed in EWB groups (b and d) (P = 0.918 and P = 0.399 respectively) which showed no significant difference, while maximum leakage scores were seen in WWB groups (a and c). Regardless of CCL application and adhesives used, EWB technique depicted (P = 0.003 and P = 0.004) significantly greater sealing ability than WWB.
Bonding of ASB and XPB using EWB significantly improved their sealing ability. Biomodification using CCL pretreatment had no significant effect on the sealing ability of adhesives bonded with either WWB or EWB.
... An important event in this respect was the discovery that these substances exhibit marked freeradical scavenger capacities (Uchida et al., 1987;Zhao et al., 1989), and that they show good bioavailability (Laparra et al., 1977). Also, there are reports of their possible use in preventing and treating atherosclerosis (Masquelier et al., 1981;Gavinet-Jeannin et al., 1988;KovacÏ and Pekic, 1991) and some cancerous diseases (Okuda, 1993). ...
The extraction of proanthocyanidins was studied in the system ethyl acetate–water–grape seeds. It was found that, in the absence of water, proanthocyanidins could not be practically extracted, and the increase in water content in the system up to the saturation level resulted in a substantial yield enhancement. It was also shown that ethyl acetate, with 10% of water, is capable of selectively extracting proanthocyanidins, which has not been the case with solvents used previously. This solvent mixture extracts mainly the proanthocyanidins of lower molecular masses, which are more important from a therapeutic point of view. A further increase in water content in the extraction system yielded a small increase in the yield of proanthocyanidins, but caused a decrease in selectivity of the extraction.
... Proanthocyanidin (PA) has been reported to stabilize and increase the cross-linkage of collagen based tissues, including dentin (Masquelier, 1981). A large number of studies have emerged over the past few years showing all the potential health benefits of PA from fruits (cranberry, grape and cocoa), leaves and bark (Cos, De Bruyne et al., 2004;Hess, Hess et al., 2008;Bertelli and Das, 2009). ...
Collagen disorganization is one of the main degradation patterns found in unsuccessful adhesive restorations. The hypothesis of this study was that pretreatment using natural collagen cross-linking agents rich in proanthocyanidin (PA) would improve mechanical properties and stability over time of the dentin collagen and, thus, confer a more resistant and lasting substrate for adhesive restorations.
PA-based extracts, from grape seed (GSE), cocoa seed (CSE), cranberry (CRE), cinnamon (CNE) and açaí berry (ACE) were applied over the demineralized dentin. The apparent elastic modulus (E) of the treated dentin collagen was analyzed over a 12 month period. Specimens were immersed in the respective solution and E values were obtained by a micro-flexural test at baseline, 10, 30, 60, 120 and 240 min. Samples were stored in artificial saliva and re-tested after 3, 6 and 12 months. Data was analyzed using ANOVA and Tukey test.
GSE and CSE extracts showed a time-dependent effect and were able to improve [240 min (MPa): GSE = 108.96 ± 56.08;CSE = 59.21 ± 24.87] and stabilize the E of the organic matrix [12 months (MPa): GSE = 40.91 ± 19.69;CSE = 42.11 ± 13.46]. CRE and CNE extracts were able to maintain the E of collagen matrices constant over 12 months [CRE = 11.17 ± 7.22;CNE = 9,96 ± 6.11;MPa]. ACE (2.64 ± 1.22 MPa) and control groups immersed in neat distilled water (1.37 ± 0.69 MPa) and ethanol-water (0.95 ± 0.33 MPa) showed no effect over dentin organic matrix and enable their degradation and reduction of mechanical properties.
Some PA-based extracts were capable of improving and stabilizing collagen matrices through exogenous cross-links induction.
... PA, the main component of the GSE (97.8%, provided by the manufacturer), is a mixture of monomers, oligomers, and polymers used as natural antioxidants and free-radical scavengers (Fujii et al., 2007). PA is known to stabilize and increase the cross-linkage of type-I collagen fibrils (Masquerlier et al., 1981). The primary mechanism of collagen stabilization with PA is the formation of hydrogen bonding between the protein amide carbonyl and the phenolic hydroxyl (Han et al., 2003). ...
Failures of dental composite restorative procedures are largely attributed to the degradation of dentin-resin interface components. Biomodification of dentin using bioactive agents may improve the quality and durability of the dentin-resin bonds. The aim of this study was to nanomechanically assess the reduced modulus of elasticity (Er) and nano-hardness (H) of major components of the dentin-resin interface (hybrid layer, adhesive layer and underlying dentin) biomodified by collagen cross-linkers at 24h, 3 and 6 months following restorative procedure. Demineralized dentin surfaces were biomodified with 5% glutaraldehyde (GD) or 6.5% grape seed extract (GSE) prior to placement of adhesive systems and composite resin. Nano-measurements of the interface components in a fluid cell showed that both agents increased the Er and H of underlying dentin after 3 and 6 months when compared to a control. The mechanical properties of the adhesive and hybrid layers decreased over time. Biomodification of the dentin-resin interface structures using GD and GSE can increase the mechanical properties of the interface over time and may contribute to the long-term quality of adhesive restorations.
Glycosaminoglycans (GAGs) form bridging cross-bands that maintain structural integrity of collagen in the organic matrix of dentine. In dentine caries, proteolytic enzymes appeared to trigger GAGs bridge degradation, followed by breakdown of the collagen network, imposing critical limitations on dentine remineralization via biomimetic mineralization of collagen. While contemporary mechanisms of collagen modification through immobilizing functional groups have been established to improve collagen mineralization, this effort remains a challenge due to lack of consideration in preserving the spatial stability of collagen. In our study, proanthocyanidins (PA) was applied to simulate the bioactivities of GAGs. Detailed analyses showed that PA reconstructed interfibrillar bridges of collapsed collagen network and reduced interfacial energy between mineral-organic phases to enhance collagen hydrophilicity, subsequently facilitating infiltration of calcium phosphate precursors and hence promoting collagen mineralization. With this strategy, mechanical behaviors of demineralized dentine were significantly improved. PA exhibited satisfactory inhibitory effects on the activity of cariogenic bacteria (comparable to that of chlorhexidine). Moreover, ex vivo study indicated that remineralization and antibacterial effects were evident in the rat oral cavity. This strategy highlights the importance of maintaining structural integrity of the collagen network in dentine remineralization and offers great clinical potential for the effective treatment of dentine caries.
الحمد لله رب العالمين والصلاة والسلام على محمد سيد الأنبياء والمرسلين وعلى آله الطيبين الطاهرين وصحبه الغر الميامين وأمته المؤمنين.
لقد أشار الكثير من الباحثين الى أن البشرية قد تعلمت الطب بطرق شتى فمنهم من يقول انه قياس ومنهم من يقول انه تجربة، ومنهم من يقول انه الهامات ومناجاة وحدس صائب ومنهم من يقول أن البشرية قد حاكت البهيمة والحيوان، وأي كان طريق اخذ الطب فانه لايرتقي علماً وممارسة الى الطب الذي اخذ بالوحي والذي لاتصل إليه علوم الناس وتجاربهم وأقيستهم. ولم يعرف التاريخ غير محمد (ص) رجلاً افرغ الله وجوده في الوجود الإنساني كله، لقد علمه الله ما لم يكن يعلم فكان المرآة الساطعة التي انعكست على صفحتها أوامر الله سبحانه وتعالى ونواهيه. (وانزل الله عليك الكتاب والحكمة، وعلمك ما لم تكن تعلم، وكان فضل الله عليك عظيماً) (النساء 113) (وما أرسلناك إلا رحمة للعالمين) (الأنبياء 107).
وكان رسول الله (ص) قد شرع التداوي وكان يستعمله في نفسه ويأمر به غيره وقد ثبت ان رسول الله (ص) كان يديم التطبيب في حال صحته ومرضه ومن الجدير بالذكر انه لم يكن من هدي الرسول (ص) استخدام الأدوية المركبة وكان جل الطب النبوي يعتمد على استخدام الأدوية المفردة وهذا ما مال إليه الطب الحديث اليوم تلافياً من حدوث التضاربات الدوائية.
وكان الرسول (ص) يراعي صفات الأطعمة وطبائعها ويراعي استعمالها على قاعدة الطب الغذائي وكان يعدل الغذاء بالغذاء فلا يمزج غذائين يرتفع مستوى محتواهما من عنصر غذائي واحد ويخلوان من عنصر آخر بل كان يجمع من الأغذية ما يمنحهما الجمع تكاملاً غذائياً.
وقد استخدم الرسول (ص) الدواء بطرق إعطاء شتى، عن طريق الفم ودهناً وغسولاً وحقنةً وحجامةً وكيَا، ولكنه كان لايحب ان يكتوي.
وقد أرسى الرسول (ص) أسس الأخلاق الطبية في ممارسة الطب فقد أخرج أبو داود والنسائي وابن ماجة حديث عمرو بن شعيب عن أبيه عن جده قال: قال رسول الله (ص) (من تطبب ولم يكن بالطب معروفاً فأصاب نفساً فما دونها فهو ضامن)
وإذ يقسم الطب النبوي الى طب علاجي وطب وقائي وطب غذائي، فان الطب النبوي طباً مرتبطاً بالإيمان والأخلاقيات السماوية، فقد أعار الطب النبوي الجوانب الروحية والأخلاقية حصة كبيرة مع انه ليس محصوراً فيها. ولضرورة هذا الجانب ولسوء استخدام الطب وكثرة الأمراض النفسية والجسمانية من جانب آخر فان الكثير من المختصين اليوم يدعون لمزج التعاليم الإسلامية بالطب الحديث لخلق خليطا متفرداً من الفن العلاجي.
وفي هذا الكتاب جمعنا الاحاديث النبوية الطبية ثم استعرضنا البحوث الطبية والدوائية التي استقصت واوضحت الفعاليات الدوائية للعلاجات النبوية وتركنا للقارئ متعة المقارنة لادراك الاعجاز في الطب النبوي.
Buckwheat (Fagopyrum esculentum) is mainly known as a food grain crop, probably originating from Siberia or China. Being tolerant to poor soils, it became in some regions a basal component in rural alimentation. In France it covered large surfaces during the 19th century before being drastically decreased in culture areas, now insufficient for the present needs (Ferault 1984); a similar phenomenon occurred in the USA. (Pomeranz 1983). This is due to different reasons such as the lack of improvement in culture yields compared to other cereals, a declining taste in the 20th century for traditional buckwheat-based foods, digestibility problems (Kreft et al. 1994) bound to phenolics, and a lower demand in animal feed.
Creat Deceiver or Mimicker is a phrase that in contemporary medicine refers to a clinical condition or disease that presents in different specialties and practices particularly resembling other clinical situations that can deceive and mislead doctors to confusion between differential diagnoses, and therefore treatment, due to the diversity of signs and symptoms. We present a deceiving case that challenged the wisdom of several professionals to arrive to the final diagnosis of Panarteritis Nodosa.
Beneficial effects of wine in relation to complex and particular composition are described. Phenolic compounds offer biological characteristics as antioxidant, antifree radical, cardiovascular disease, etc. Several toxicological aspects of wine in relation to lead content, methanol, ethyl carbamate, SO 2, plaguicides are also reported. However, control quality in wine is more exhaustive than in other alcoholic beverages.
In this review of CAM for cardiovascular diseases, it is important to note that supplements, herbs, and other dietary or pharmacologic treatments are among the CAM therapies that have specific biologic effects. In general, there is a growing body of scientific evidence conducted in vitro and in animals that supports the mode of action of these CAM treatments. Many supplements and herbs also have been studied in humans; however, these trials are often small, sometimes poorly designed, and either not replicated or published in less accessible journals. Several herbs, however, have been better studied, including garlic for cholesterol lowering and hypertension, ginkgo biloba for intermittent claudication, and hawthorn for congestive heart disease. Standardized high-quality products developed from these herbs are likely to be used extensively by patients. Although a complementary role may be justified for many herbs or supplements, the evidence to date does not support replacing conventional treatment with CAM modalities.
To evaluate the effect of GSE, NaOCl, CHX and QMix as an antimicrobial agents against E. faecalis and their influence on flexural and ultimate tensile strength of root canal dentine.
Root canals were divided into five groups (n=10) according to the substances used: 2.5% NaOCl, 2% CHX, 6.5% GSE, Qmix and control group (distilled water) (DW). Final irrigation was done with 17% EDTA in all groups, except when DW was used. The number of colony-forming units was used to evaluate the antimicrobial activity. Dentine beams were used to assess the flexural strength after treatment with substances as described before (n=10). The UTS was evaluated after the treatment of root dentine hourglass shape sections with the same substances (n=30).
The lowest bacteria contamination was observed for CHX and GSE, while NaOCl and QMix showed an intermediate antimicrobial activity (p>0.05). NaOCl and QMix significantly reduced the mechanical properties of dentine (flexural strength and UTS) (p<0.05) and no statistical difference was found among CHX, GSE and DW (p>0.05).
CHX and GSE were more effective than NaOCl and QMix against E. faecalis. Furthermore, they did not harm dentine mechanical properties as observed for NaOCl and QMix.
The use of GSE can be recommended for endodontic procedures since it has good antimicrobial activity and does not interfere in the mechanical properties of dentine; similarly to CHX.
Copyright © 2015. Published by Elsevier Ltd.
ObjectifDans un travail précédent, nous avons montré que les oligomères procyanidoliques des pépins de raisin (OPC) protègent efficacement le stroma cornéen contre l’effet dégradant de la collagénase bactérienne. Dans le présent travail, nous avons étudié l’effet des OPC sur la composition en protéines et en collagènes de la cornée, et sur la biosynthèse des collagènes de la cornée.MéthodesNous avons travaillé sur des cornées bovines en cultures d’explant. Nous avons dosé les protéines totales et le collagène, ainsi que l’incorporation de la proline tritiée dans les collagènes. Nous avons également quantifié les trois types principaux des collagènes de la cornée (types I, V et VI). Finalement, pour comprendre certains des résultats obtenus, nous avons étudié l’interaction in vitro des OPC avec le collagène de type I.RésultatsEn l’absence d’OPC dans les milieux d’incubation, les dosages, les typages des collagènes et l’étude de l’incorporation du précurseur radioactif reflétaient la composition d’une cornée normale avec les proportions habituelles des trois principaux types de collagènes du stroma. En présence d’OPC, principalement après 24 heures d’incubation et avec la concentration d’OPC de 1 mg/ml la quantité totale dosée des protéines et des collagènes a diminué et les proportions de ces constituants extractibles par la pepsine ont diminué, et la partie extractible par la potasse éthanolique a légèrement augmenté. Les proportions des trois types de collagènes étaient également modifiées : le collagène de type I est devenu prépondérant et la proportion des deux autres a diminué. L’interaction in vitro des OPC avec le collagène de type I a montré que 30 % du principe actif ne se fixe pas sur le collagène, 20 % se fixe réversiblement et 50 % se fixe irréversiblement. Les OPC de cette dernière fraction ne peuvent plus être séparés du collagène ni par chromatographie sur colonne, ni par action de la collagénase ou de la potasse éthanolique.ConclusionLes cornées bovines mises en cultures d’organe en présence d’OPC voient leur composition en protéines totales et en collagènes modifiée, et les proportions relatives des trois types principaux de collagènes du stroma, les types I, V et VI sont également modifiées. Ces modifications sont essentiellement caractérisées par la prédominance du collagène de type I et la baisse des autres types avec une baisse importante de la solubilité. L’étude de l’interaction du collagène de type I avec les OPC a montré que 50 % des OPC se fixent irréversiblement sur le collagène qui devient ainsi résistant à la collagénase, pouvant normalement le solubiliser. Cette forte interaction entre OPC et collagène explique la baisse des quantités de protéines et collagènes dosées dans les extraits des cornées incubées en présence d’OPC.PurposeWe showed in a previous study that procyanidolic oligomers (PCOs) from grape seeds effectively protect corneal stroma against degradation by bacterial collagenase. Here we report the study of the effect of PCOs on protein and collagen composition of cornea and on the biosynthesis of corneal collagens.Methods
Bovine corneas were used in explant cultures. We quantitatively determined total proteins and collagen as well as the incorporation of 3H-proline in separated collagen types. Collagens type I, V, and VI were separated and quantitated. In order to understand some of the results obtained, we studied the interaction of PCO with collagen type I separately.ResultsIn the absence of PCOs, collagen typing and 3H-proline incorporation yielded the expected results for a normal cornea, with the usual proportion of the three major types of collagens. In presence of PCOs at 1mg/ml and after 24h incubation, total proteins and collagens decreased, as did papain-extractable collagens. Proteins in the final residue solubilized in 1M KOH-80% v/v aqueous ethanol increased. The proportion of the three principal collagens was also modified: type I became preponderant, and the proportions of the two others (type V and VI) decreased. The study of the interaction of collagen type I with PCOs showed that 30% of total PCOs do not interact with collagen, 20% interact reversibly, and 50% of PCOs are strongly and irreversibly fixed. This strongly fixed fraction could not be separated from collagen by either column chromatography or collagenase or KOH in aqueous ethanol.Conclusions
Bovine corneas in explant cultures in presence of PCOs undergo a modification of their protein and collagen content, with a concurrent modification of the proportion of collagens types I, V, and VI. Collagen type I predominates, and the two other types decrease. Study of the collagen type I-PCO interaction showed that roughly 50% of PCOs become irreversibly fixed to collagen, resisting collagenase or other methods of separation. This strong PCO-collagen type I interaction explains the decrease in solubility.
The effects of interactions between cross-linking proanthocyanidins (PA) in polar solvents and type-I collagen of demineralized dentin were investigated.
Three PA-rich extracts, two from grape seed (GSEP and GSES) and one from cocoa (COE), were dissolved (water, ethanol:water and acetone:water) and analyzed for their ability to increase the modulus of elasticity of demineralized dentin. Sound dentin beams (0.5mmx1.7mmx7mm) were fully demineralized and divided into 12 groups according to the type of cross-linking agent and solvents used. Specimens were immersed in the respective solutions and tested at baseline, 10, 30, 60, 120 and 240min.
The elastic modulus (EM) of dentin was significantly increased by the PA treatment regardless of time (p<0.05 for all times). The extracts showed different solubility in different solvents. GSEP showed the highest increase in EM when diluted in distilled water and acetone at all exposure times. Both GSEs showed superior results when diluted in distilled water and after 4h of treatment, while COE produced strongest enhancement when dissolved in ethanol:water.
The results indicates that herbal extraction process and other pharmacognostic parameters have an important influence on extract solubility as well as constitution and, consequently, on the PA-dentin matrix interaction.
Blood-brain barrier (BBB) is the site of regulatory mechanisms which control the exchange of substances between the brain and the blood through the wall of 'true' brain capillaries with tight junctions between endothelial cells. In some pathological situations the permeability of the BBB is increased because of a partial proteolytic degradation of some constituents of the capillary basement lamina. In such cases it is important to restore normal permeability. The effect of procyanidolic oligomers (PCO) on the BBB was investigated in vivo with quantitative morphologic procedures. We also investigated the action of this drug on collagen and basement lamina constituents (Matrigel) in vitro. Collagenase injected in lateral brain ventricles was shown to increase BBB permeability. Per os administration of PCO to rats greatly increased the resistance of brain capillaries to bacterial collagenase, as shown by the inhibition of the diffusion of fluorescein-isothiocyanate-marked dextran particles from the blood-stream into the brain tissues. Calf skin collagen pretreated in vitro with PCO became more resistant to the hydrolytic action of collagenase. Similar, even more intense protective effect was seen when basal lamina constituents containing type IV collagen was incubated with PCO before exposure to pronase. These in vitro effects may partly explain the in vivo protective effect of PCO against the alteration of brain capillaries by i.v. injected bacterial collagenase.
As a clinician treating musculoskeletal conditions, one is continually in search of safe and more effective treatment methods that will hasten tissue healing. Chronic inflammation has been shown to cause connective tissue degradation. Typically, nonsteroidal anti-inflammatory drugs (NSAIDs) and/or corticosteroids are used to control the inflammatory process, however, long-term use has been associated with potentially serious side effects. The purpose of this article is to introduce and describe literature on 2 natural compounds, namely, proanthocyanidin (PCO) and quercetin, which are 2 specific types of bioflavonoids, and to discuss their potential benefits in treating musculoskeletal conditions. There is evidence to suggest that flavonoids may be beneficial to connective tissue for several reasons, which include the limiting of inflammation and associated tissue degradation, the improvement of local circulation, as well as the promoting of a strong collagen matrix. An overview of bioflavonoids as well as relevant research, safety issues, absorption, and specific sources of PCO and quercetin in foods and through supplementation is included.
Grape seed polyphenols have been reported to exhibit a broad spectrum of biological properties. In this study, eleven phenolic phytochemicals from grape seeds were purified by gel chromatography and high performance liquid chromatography (HPLC). The antioxidant activities of five representative compounds with different structure type were assessed by the free radical-scavenging tests and the effects of the more potent phytochemicals on oxidative damage to DNA in mice spleen cells were investigated. Procyanidin B4, catechin, epicatechin and gallic acid reduced ferricyanide ion and scavenged the stable free radical, alpha, alpha-diphenyl-beta-picrylhydrazyl (DPPH) much more effectively than the known antioxidant vitamin ascorbic acid, while epicatechin lactone A, an oxidative derivative of epicatechin, did not reduce ferricyanide ion appreciably at concentrations used and was only about half as effective on free radical-scavenging as epicatechin. Mice spleen cells, when pre-incubated with relatively low concentration of procyanidin B4, catechin or gallic acid, were less susceptible to DNA damage induced by hydrogen peroxide (H2O2), as evaluated by the comet assay. In contrast, noticeable DNA damage was induced in mice spleen cells by incubating with higher concentration (150 microM) of catechin. Collectively, these data suggest that procyanidin B4, catechin, gallic acid were good antioxidants, at low concentration they could prevent oxidative damage to cellular DNA. But at higher concentration, these compounds may induce cellular DNA damage, taking catechin for example, which explained the irregularity of dose-effect relationship.
In the present study, the root extract of Rhus oxyacantha contained 25.33 mg of catechin equivalent per mg of fresh wt and was found rich in proanthocyanidins compared to vine shoot, grape pips and leaves. The chromatographic analysis of the extract suggested the presence of (+) catechin, (-) epicatechin -3-O-gallate as well as proanthocyanidinic oligomers and polymers. Root cortex inhibited the ascorbic acid oxidation by dioxygen. It also prevented DDT-induced thymocytes death in a dose-dependent manner. The results suggested antioxidant property of root extract of Rhus oxyacantha which could be ascribed to its free radical scavenging nature.
ResearchGate has not been able to resolve any references for this publication.