Procyanidin A_1 and its digestive products alleviate acrylamide-induced IPEC-J2 cell damage through regulating Keap1/Nrf2 pathway

Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.

Effect of dual targeting procyanidins nanoparticles on metabolomics of lipopolysaccharide-stimulated inflammatory macrophages

Inflammation plays an important role in the occurrence and development of many inflammatory diseases.The purpose of this study was to evaluate the anti-inflammatory effect and metabolic behavior of the dual targeting procyanidins(PC)nanoparticles on lipopolysaccharide(LPS)-stimulated inflammatory macrophages by metabolomics method.The double-targeting PC nanoparticles could specifi cally target both the CD44 receptor and mitochondria,while the single targeting PC-loaded nanoparticles that could target the CD44 receptor on the surface of macrophages.The double-targeting PC nanoparticles had better inhibitory effect than single-targeting PC nanoparticles on the leakage of lactate dehydrogenase and reactive oxygen species overexpression induced by LPS.Amino acid metabolism,energy metabolism and purine metabolism were disordered in LPS-treated group,and metabolic pathway analysis indicated that the double-targeting PC nanoparticles reversed some of LPS impacts.The changes of these potential biomarkers and their corresponding pathways are helpful to further understand the mechanism of PC nanoparticles in alleviating inflammation,and promote their application in nutrition intervention.

Antioxidant procyanidin B2 protects oocytes against cryoinjuries via mitochondria regulated cortical tension

Background:Irreversible cryodamage caused by oocyte vitrification limited its wild application in female fertility preservation.Antioxidants were always used to antagonist the oxidative stress caused by vitrification.However,the comprehensive mechanism underlying the protective role of antioxidants has not been studied.Procyanidin B2(PCB2)is a potent natural antioxidant and its functions in response to vitrification are still unknown.In this study,the effects of PCB2 on vitrified-thawed oocytes and subsequent embryo development were explored,and the mechanisms underlying the protective role of PCB2 were systematically elucidated.Results:Vitrification induced a marked decline in oocyte quality,while PCB2 could improve oocyte viability and further development after parthenogenetic activation.A subsequent study indicated that PCB2 effectively attenuated vitrification-induced oxidative stress,rescued mitochondrial dysfunction,and improved cell viability.Moreover,PCB2 also acts as a cortical tension regulator apart from strong antioxidant properties.Increased cortical tension caused by PCB2 would maintain normal spindle morphology and promote migration,ensure correct meiosis progression and finally reduce the aneuploidy rate in vitrified oocytes.Further study reveals that ATP biosynthesis plays a crucial role in cortical tension regulation,and PCB2 effectively increased the cortical tension through the electron transfer chain pathway.Additionally,PCB2 would elevate the cortical tension in embryo cells at morula and blastocyst stages and further improve blastocyst quality.What's more,targeted metabolomics shows that PCB2 has a beneficial effect on blastocyst formation by mediating saccharides and amino acids metabolism.Conclusions:Antioxidant PCB2 exhibits multi-protective roles in response to vitrification stimuli through mitochondria-mediated cortical tension regulation.

Procyanidin B2 protects against diet-induced obesity and non-alcoholic fatty liver disease via the modulation of the gut microbiota in rabbits

BACKGROUND Procyanidins have beneficial effects on metabolic syndrome and antimicrobial activity,but the mechanisms underlying these effects are unclear.AIM To investigate the effects of procyanidin B2(PB2)on non-alcoholic fatty liver disease and to explore the possible mechanism.METHODS Thirty male New Zealand white rabbits were randomized into three groups.All of them were fed either a high-fat-cholesterol diet(HCD)or chow diet.HCD-fed rabbits were treated with vehicle or PB2 daily for 12 wk.Body weight and food intake were evaluated once a week.Serum biomarkers,such as total cholesterols,triglycerides,and aspartate transaminase,were detected.All rabbits were sacrificed and histological parameters of liver were assessed by hematoxylin and eosin-stained sections.Moreover,several lipogenic genes and gut microbiota(by 16S rRNA sequencing)were investigated to explore the possible mechanism.RESULTS The HCD group had higher body weight,liver index,serum lipid profile,insulin resistance,serum glucose,and hepatic steatosis compared to the CHOW group.PB2 treatment prevented HCD-induced increases in body weight and hypertriglyceridemia in association with triglyceride accumulation in the liver.PB2 also ameliorated low-grade inflammation,which was reflected by serum lipopolysaccharides and improved insulin resistance.In rabbit liver,PB2 prevented the upregulation of steroid response element binding protein 1c and fatty acid synthase and the downregulation of carnitine palmitoyltransferase,compared to the HCD group.Moreover,HCD led to a decrease of Bacteroidetes in gut microbiota.PB2 significantly improved the proportions of Bacteroidetes at the phylum level and Akkermansia at the genus level.CONCLUSION Our results indicate the possible mechanism of PB2 to improve HCD-induced features of metabolic syndrome and provide a new dietary supplement.

Neuroprotective Effects of Grape Seed Procyanidin Extracton Ischemia-Reperfusion Brain Injury

客观氧化应力(OS ) 在 ischemic 击起一个关键作用。葡萄种子 procyanidin 摘录(GSPE ) 被报导是 OS 的一个批评管理者。我们假设了那 GSPE 可能也在 ischemia-reperfusion 大脑损害保护。这研究试图探索 GSPE 管理是否能保护老鼠免受 ischemia-reperfusion 大脑 injury.Methods 的伤害短暂中间的服的动脉吸藏(MCAO ) 被进行由灌注列在后面 24 个小时在收到了 GSPE 的老鼠使 ischemia-reperfusion 成为大脑损害(MCAOG， n=60 ) 或正常盐(MCAONS， n=60 ) 。假冒操作老鼠(GSPE 组和正常的盐的组) 被放作为控制。神经病学的严厉分数(NSS ) 被用来在 MCAO 以后评估神经功能缺陷 1 小时， 24 小时， 3 天和 7 天。鼠标与一台 3T 动物 MRI 扫描仪经历了大脑 T2WI 成像在灌注以后的 24 个小时，和大脑的击卷根据反常信号紧张被计算。在在灌注以后的 24 h 的大脑纸巾的 Immunohistopathological 分析为 neuronal 被执行原子抗原(NeuN ) ， CD34， Bcl-2，和 Bax。谷胱甘肽 peroxidation (GSH-Px ) 活动和大脑织物的 malonaldehyde (MDA ) 的水平也被检验。上述索引在组 statistically.Results 之中被比较重要功能的改进被观察在在与 MCAONS 相比的 MCAOG 组的 MCAO 以后的 24 个小时组织(P < 0.05 ) 。MCAOG 组有更小的服的击体积(22.46 ? ┷ ? 有 ? ┷ ????????????????? 倠 ??? ‵? ￡ ?? 蟸吗？？

Procyanidins Inhibit Tumor Angiogenesis by Crosslinking Extracellular Matrix

Objective： Procyanidins （PC） are widely available natural polyphenols. The present study is designed to investigate if PC can inhibit angiogenesis in lung adenocarcinoma xenografts through crosslinking vascular extracellular matrix （ECM） and preventing proteolysis by matrix metalloproteinases （MMPs）. Methods： Using the in vitro MMP-2 proteolysis and in vivo subcutaneous implantation models, we investigated if PC crosslinking inhibits MMP-mediated proteolysis. Using a cultured cell detachment assay, an in vitro angiogenesis assay, and a cell proliferation assay, we investigated if PC inhibits MMP-2-mediated endothelial cell detachment, angiogenesis, and cell proliferation, respectively. Using tumor xenografts, we evaluated if PC can inhibit growth of lung adenocarcinoma. Results： PC crosslink vascular ECM proteins, protecting them against proteolysis by MMPs in vitro and in vivo, protecting cultured human umbilical vein endothelial cells from detachment by MMP-2, and inhibiting in vitro angiogenesis. However, PC （0.75-100 μg/mL） did not inhibit vascular and tumor cells proliferation. PC injections （30 mg PC/kg bodyweight） in situ had anticancer effects on xenografts of lung adenocarcinoma, most likely by inhibiting angiogenesis during ECM proteolysis by MMPs. Conclusion： The results suggest that PC may be important MMP inhibitors that can be used as therapeutic anticancer agents.

The Protective Role of Procyanidins and Lycopene Against Mercuric Chloride Renal Damage in Rats

Objective This study aims to investigate the protection of procyanidins and lycopene from the renal damage induced by mercuric chloride.Methods Rats were treated with either procyanidins or lycopene 2h before HgCl 2 subcutaneously injection,once daily treatment for 2 successive days.Results In comparison with HgCl 2 group,markers of renal function such as blood urea nitrogen in serum and urinary protein were decreased to （18.45±11.63） mmol/L and （15.93±9.36） mmol/L,（4.54±0.78） g/（g Cr） and （4.40±1.12） g/（g Cr）.N‐acetyl‐beta‐D‐glucosaminidase,lactate dehydrogenase,alkaline phosphatase in urine were depressed to （125.49±11.68） U/（g Cr）,（103.73±21.79） U/（g Cr）,（101.99±12.28） U/（g Cr）,and （113.19±23.74） U/（g Cr）,（71.14±21.80） U/（g Cr）,（73.64±21.51） U/（g Cr） in procyanidins and lycopene groups.Indicators of oxidative stress,for example,Glutathion was reduced to （45.58±9.89） μmol/（g pro） and （45.33±5.90） μmol/（g pro）,and antioxidant enzymes such as superoxide dismutase,glutathione‐peroxidase were enhanced to （43.07±10.97） U/（mg pro） and （39.94±6.04） U/（mg pro）,（83.85±18.48） U/（mg pro）,and （85.62±12.68） U/（mg pro）.Malondialdehyde was lowered to （0.95±0.12） （μmol/g pro） and （1.03±0.12） μmol/（g pro） in procyanidins and lycopene groups.ROS generation was decreased by 27.63% and 16.40% and apoptosis was also decreased in procyanidins and lycopene groups respectively.Pathological changes were much better as well.Conclusion Procyanidins and Lycopene play some protective role against mercury kidney damage.

Protective Effect of Procyanidin B2 on Acute Liver Injury Induced by Aflatoxin B1 in Rats

Objective This study aimed to explore the protective effect of procyanidin B2(PCB2)on acute liver injury induced by aflatoxin B1(AFB1)in rats.Methods Forty Sprague Dawley rats were randomly divided into control,AFB1,AFB1+PCB2,and PCB2 groups.The latter two groups were administrated PCB2 intragastrically(30 mg/kg body weight)for 7 d,whereas the control and AFB1 groups were given the same dose of double distilled water intragastrically.On the sixth day of treatment,the AFB1 and AFB1+PCB2 groups were intraperitoneally injected with AFB1(2 mg/kg).The control and PCB2 groups were intraperitoneally administered the same dose of dimethyl sulfoxide(DMSO).On the eighth day,all rats were euthanized:serum and liver tissue were isolated for further examination.Hepatic histological features were assessed by hematoxylin and eosin-stained sections.Weight,organ coefficient(liver,spleen,and kidney),liver function(serum alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,total bilirubin,and direct bilirubin),oxidative index(catalase,glutathione,superoxide dismutase,malondialdehyde,and 8-hydroxy-2′-deoxyguanosine),inflammation factor[hepatic interleukin-6(IL-6)m RNA expression and serum IL-6],and bcl-2/bax ratio were measured.Results AFB1 significantly caused hepatic histopathological damage,abnormal liver function,oxidative stress,inflammation,and bcl-2/bax ratio reduction compared with DMSO-treated controls.Our results indicate that PCB2 treatment can partially reverse the adverse liver conditions induced by AFB1.Conclusion Our findings indicate that PCB2 exhibits a protective effect on acute liver injury induced by AFB1.

Anti-inflammatory and anti-arthritic activity of type-A procyanidine polyphenols from bark of Cinnamomum zeylanicum in rats

Type-A procyanidine polyphenols(TAPP)are reported to have immunomodulatory and anti-inflammatory potential in vitro.The objective of present work is to evaluate potential of TAPP extracted from Cinnamon(Cinnamomum zeylanicum)bark in animal models of inflammation and rheumatoid arthritis in rats.Carrageenan-induced rat paw edema(CPE)and adjuvant induced established arthritis(AIA),in rats were used as the experimental models for inflammation and arthritis respectively.Analgesic activity was evaluated in Randall–Selitto assay in AIA rats.TAPP showed significant anti-inflammatory effect at dose of 4,8 and 25 mg/kg,p.o.but not at 2 mg/kg,p.o.dose in CPE model.The dose of 8 mg/kg,p.o.was selected for the evaluation of anti-arthritic activity in AIA model.TAPP(8 mg/kg,p.o.,daily from day-12 to day-21)treatment in established arthritic rats showed significant reversal of changes induced in AIA with respect to body weight drop(cachexia),ankle diameter,arthritic score,serum C-reactive protein(CRP)levels.Moreover,TAPP was found to be non-ulcerogenic as compared to AIA control rats.However,TAPP did not show analgesic effect on AIA-induced pain as seen in Randall–Selitto assay.In conclusion,TAPP showed disease-modifying potential in animal models of inflammation and arthritis in rats.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved.

EFFECT OF PROCYANIDIN ON CELL CYCLE IN MURINE LEWIS LUNG CARCINOMA

Objective: To investigate the anti-tumor effect of procyanidin (WeiMaiNing, WMN) on a murine Lewis lung carcinoma cell line (3LL) and the influence on the cell cycle. Methods: The inhibitory rate of 3LL growth was detected in the model of murine Lewis lung carcinoma. The effect of the drug on 3LL cell cycle and the influence of the drug on the expression of cyclin D1 protein were investigated by flow cytometry, immunohistochemical staining. Results: The inhibitory rates of WMN in 3LL were 19.14%, 33.59% and 51.56% respectively at dosages 100 mg穔g-1穌-1, 150 mg穔g-1穌-1 and 250 mg穔g-1穌-1. The inhibitory effect was in a dose-dependent manner. We found WMN significantly increased (P<0.01) the number of 3LL cells in G0-G1 phase (35.97% vs. 27.2% at 150 mg穔g-1穌-1 WMN; 40.10% vs. 27.2% at 250 mg穔g-1穌-1 WMN) and decreased the expression of cyclin D1, PCNA protein. Conclusion: WeiMaiNing inhibits the growth of 3LL cells in vivo by decreasing the expression of PCNA and cyclin D1, blocking the cells in G0-G1 phase and preventing the cells transition from G1 to S phase while DNA is replicated.

Dose-dependent effects of procyanidin on nerve growth factor expression following cerebral ischemia/reperfusion injury in rats

BACKGROUND： Recently, grape seed procyanidin （GSP） has been shown to be exhibit antioxidant effects, effectively reducing ischemia/reperfusion injury and inhibiting brain cell apoptosis. OBJECTIVE： To study the effects of GSP on nerve growth factor （NGF） expression and neurological function following cerebral ischemia/reperfusion injury in rats. DESIGN： Randomized controlled study based on SD rats. SETTING： Weifang Municipal People＇s Hospital. MATERIALS： Forty-eight healthy adult SD rats weighing 280-330 g and irrespective of gender were provided by the Experimental Animal Center of Shandong University. GSP derived from grape seed was a new high-effective antioxidant provided by Tianjin Jianfeng Natural Product Researching Company （batch number： 20060107）. Rabbit-anti-rat NGF monoclonal antibody was provided by Beijing Zhongshan Biotechnology Co., Ltd., and SABC immunohistochemical staining kit by Wuhan Boster Bioengineering Co., Ltd. METHODS： The present study was performed in the Functional Laboratory of Weifang Medical College from April 2006 to January 2007. Forty-eight SD rats were randomly divided into the sham operation group, ischemia/reperfusion group, high-dose GSP （40 mg/kg） group, or low-dose GSP （10 mg/kg） group （n = 12 per group）. Ischemia/reperfusion injury was established using the threading embolism method of the middle cerebral artery. Rats in the ischemia/reperfusion model group were given saline injection （2 mL/kg i.p.） once daily for seven days pre-ischemia/reperfusion, and once more at 15 minutes before reperfusion. Rats in the high-dose and low-dose GSP groups were injected with GSP （20 or 5 mg/mL i.p., respectively, 2 mL/kg） with the same regime as the ischemia/reperfusion model group. The surgical procedures in the sham operation group were as the same as those in the ischemia/reperfusion model group, but the thread was approximately 10 mm long, thus, the middle cerebral artery was not blocked. MAIN OUTCOME MEASURES： NGF expression in the ischemic penumbra of the temporal cortex was detected by immunohistochemistry, and positive cells counted by light microscopy （×400）. The positive cell rate was calculated by [（positive cells/total cells）× 100%]. Neurological function was scored after 2-hour ischemia/48-hour reperfusion. Higher scores reflected more severe neurofunctional defect. RESULTS： The positive rate of NGF expression in all groups receiving ischemia/reperfusion was significantly higher than that in the sham operation group （q=3.87, P 〈 0.05）. The positive rate of NGF expression in the high-dose and low-dose GSP groups were significantly higher than that in the model group （q=4.12, P 〈 0.05）, and were greater in the high-dose compared to low-dose GSP groups （q=4.22, P 〈 0.05）. Neurological function scores in the high-dose and low-dose GSP groups were significantly lower than that in the ischemia/reperfusion model group （q=3.92, P 〈 0.05）. Neurological function score in the high-dose GSP group was significantly less than that in the low-dose GSP group （q=4.02, P 〈 0.05）. CONCLUSION： GSP may up-regulate brain-derived NGF expression in a dose-dependent manner following cerebral ischemia/reperfusion injury in order to improve neurological function and protect the brain.

Grape Seed Procyanidin Extract Reduces Arsenic- Induced Renal Inflammatory Injury in Male Mice

The aim of the present study is to evaluate the ability and mechanism by which grape seed procyanidin extract （GSPE） relieves arsenic trioxide （As2O3）-induced renal inflammatory injury. Therefore, male Kunming mice were treated with As2O3 and/or GSPE by gavage for 5 weeks. Mice were then sacrificed and inflammatory cytokines of kidneys were examined by ELISA, whereas the expression levels of molecules involved in the nuclear factor （NF）-KB signaling pathway were evaluated by both qRT-PCR and Western blot. Our results indicate that GSPE prevents As2O3-mediated renal inflammatory injury by inhibiting activation of the NF-KB signaling pathway and inflammatory cytokine production, while promoting expression of anti-inflammatory cytokines.

Technical Study on Extraction of Procyanidins in Lycium ruthenicum Murr. Using Sub-critical Fluid 1,1,1,2-Tetrafluoroethane( R134a)and Content Determination from Different Producing Areas

[Objectives] To study the optimal conditions for extracting procyanidins fromLycium ruthenicum Murr. with sub-critical fluid R134 a( 1,1,1,2-tetrafluoroethane) in 1 L extraction kettle. [Methods]Taking the extraction rate of procyanidins as an indicator,the influence of pressure,temperature,and extraction time on extraction rate of procyanidins fromL. Ruthenicum Murr. was studied by single factor experimental methods and orthogonal array design. [Results]The order of factors affecting extraction rate of procyanidins was extraction temperature > extraction pressure > extraction time. The optimum extraction conditions were as follows: the extraction rate of procyanidins fromL. ruthenicum Murr. was the highest with extraction pressure of 1. 2 MPa,extraction temperature of 50℃ and extraction time of 90 min. The content of procyanidins in L. ruthenicum Murr. from different producing areas was determined by vanillin-HCl method under the optimal conditions. [Conclusions] The method has the advantages of easy operation,good selectivity,low extraction temperature and high extraction efficiency,which is suitable for extraction of procyanidins in L. ruthenicum Murr.

The protective effects of procyanidin C-1 on bisphenol A-induced testicular dysfunction in aged mice

The number and quality of sperm are decreased due to bisphenol A(BPA) exposure, an endocrine-disrupting chemical on the male reproductive system, especially in advanced paternal age(APA). Procyanidin C-1(PCY-1), an antioxidant from grape seed(Vitis vinifera L.), has demonstrated anti-viral, anti-melanogenic and immunostimulatory effects. Therefore, this study aims to determine the effects of PCY-1 intervention on sperm parameters, testis morphological changes, serum testosterone, oestradiol, and luteinizing hormone(LH) concentrations and the expression of apoptotic(Bax and Bcl-2) and mitochondria-related(Mfn1 and Opa1) genes in BPA-exposed aged mice. Results revealed that PCY-1 intervention improves aged male fertility in BPA-exposed conditions by decreasing abnormal sperms percentage and increasing spermatogenic cell diameter and epithelial height. PCY-1 also decreased oestradiol, and increased LH and testosterone levels. The gene expression of Bax was significantly down-regulated by PCY-1 intervention. In contrast, Bcl-2 was substantially up-regulated. Expression of Mfn1 and Opa1 genes were also significantly up-regulated in the PCY intervention group. Hence, it is demonstrated that PCY-1 was able to mitigate the adverse effects of BPA on reproductive parameters of aged mice. Collectively, we postulated that PCY-1 has a potential role in protecting the ageing male reproductive system against the damaging impacts of BPA.

Crosslinking of Bovine Pericardia Using Procyanidins

The aim of this study was to evaluate the crosslinking effect of a naturally crosslinking reagent-procyanidins(PA)-on the materials of bioprosthetic heart valves.After fixing bovine pericardial tissues by procyanidins,crosslikng characteristics,mechanical properties,in vitro enzymatic degradation resistance,the hydrophilicity and hemolysis tests were examined.The results showed that the fixation of biological tissue with glutaraldehyde(GA) or procyanidins increased its denaturation temperature,the surface hydrophilicity and mechanical properties as well as in vitro enzymatic degradation resistance.There were no significant differences in denaturation temperature,mechanical properties,the hydrophilicity and the in vitro enzymatic degradation between the glutaraldehyde and procyanidins fixed tissues.However,the ultimate tensile strength of the procyanidins fixed tissues was significantly superior to the glutaraldehyde fixed tissues.The hemolysis tests showed that hemolysis rate of the procyanidins fixed tissues was lower than that of the glutaraldehyde fixed tissues.This study shows that procyanidins can crosslink which bovine pericardiaa effectively without toxicity.Our results suggest that this method might be a useful approach for the preparation of bioprosthetic heart valve.

Efficient semisynthetic approach for large preparation of procyanidin C1 through degradation of grape seed polymeric procyanidins

An efficient method for producing trimeric procyanidin C1(PCC1)was developed through degradation of grape seed polymeric procyanidins(PPCs),using epicatechin(EC)as nucleophile and hydrochloric acid as catalyst.With the yield of PCC1 as the evaluation index,the degradation conditions were optimized by Box-Behnken Design(BBD)based on the results of single-factor experiments.The results showed that the optimal conditions were reaction temperature of 40℃,the ratio of EC and PPCs 2:1,acidity of 0.10 mol/L,and reaction time of 20 min.The yield of PCC1 reached up to 17.7 mg by only one-step degradation of 3 g PPCs.This work proposed a new method for large preparation of PCC1 from waste grape seed polymeric procyanidins.

Effect of enzymatic extraction conditions on the yield and the polymerization degree of procyanidins

Grape seeds are rich sources of procyanidin(PCs)known for potential health benefi ts.In this study,PCs were extracted from defatted grape seeds by enzymatic method in which pectinase and cellulase were used.The enzyme extraction process was further optimized by single factor experiment and response surface methodology.The optimal conditions were as follows:ethanol concentration of 70%,extraction time of 70 min,extraction temperature of 35℃,liquid/solid ratio of 103:1(mL/g),pectinase/cellulase ratio of 1:1,enzyme/solid ratio of 1:314 w/w.Under the above conditions,the extraction yields and mean degree of polymerisation(mDP)of PCs reached 47.18 mg/g dry material weight and 11.2,respectively.Compared with other extraction methods,enzyme extraction can obtain PCs with higher yield and lower mDP.According to the antioxidant activity test,PCs extracts with lower mDP showed better ability to clear 1,1-Diphenyl-2-picrylhydrazyl radical(DPPH).Enzymatic extraction was an effi cient method to obtain oligomeric procyanidin which has stronger antioxidant activity.

Inhibitory effects of grape procyanidins on free radical-induced cell damage in rat hepatocytes in vitro

AIM: To study the protective effect of grape procyanidins on oxidative injury induced by ethanol and carbon tetrachloride in rat hepatocytes. METHODS: Normal rat hepatocytes as well as cells damaged by ethanol or carbon tetrachloride were incubated with different doses of grape procyanidins for 24 h. Cell proliferation, apoptosis and TNFα mRNA expression were subsequently determined using MTT assay, cell death ELISA and in situ hybridization.RESULTS: Proliferative levels of the control cells from ethanol and CCl4 injury groups significantly decreased while apoptosis and TNFα mRNA expression signifi cantly increased compared to the normal control and grape procyanidins co-treatment groups (0.455 ± 0.051 vs 0.318 ± 0.045, P < 0.05). In comparison with the normal control, 50 and 100 mg/L grape procyanidins significantly stimulated cell growth, with a better effect observed with 100 mg/L grape procyanidins. CONCLUSION: Grape procyanidins inhibit the hepatocyte damage induced by ethanol and carbon tetrachloride, and stimulate normal hepatocyte proliferation.

Optimization of Enzyme-assisted Extraction Technology for Tartary Buckwheat Shell Procyanidins with Response Surface Methodology

This study was conducted to investigate the effects of cellulase dosage, enzymolysis time, pH and enzymolysis temperature on procyanidin extraction rate by single factor experiment, with tartary buckwheat shell as an experimental material.Main process parameters were optimized to obtain a regression model by response surface methodology. The results of variance analysis indicated that the regression model reflected the relationship between buckwheat shell procyanidin extraction rate with enzyme dosage, enzymolysis time, pH and enzymolysis temperature; and the optimal process parameters were enzyme dosage of 6.5 mg/g, enzymolysis time of 1.5 h, pH at 4.7 and enzymolysis temperature at 46 ℃. Three parallel experiments were conducted under these process parameters. In practice, the highest procyanidin extraction rate was 6.78 g/100 g. The relative error between the predicted value of regression model and the actual value was 1.3%. The regression equation fitted the real situation better.

Oligomeric procyanidins combined with Parabacteroides distasonis ameliorate high-fat diet-induced atherosclerosis by regulating lipid metabolism,inflammation reaction and bile acid metabolism in ApoE^(-/-)mice

Atherosclerosis(AS)is the main pathological basis of cardiovascular diseases.Hence,the prevention and treatment strategies of AS have attracted great research attention.As a potential probiotic,Pararabacteroides distasonis has a positive regulatory effect on lipid metabolism and bile acids(BAs)profile.Oligomeric procyanidins have been confirmed to be conducive to the prevention and treatment of AS,whose antiatherosclerotic effect may be associated with the promotion of gut probiotics.However,it remains unclear whether and how oligomeric procyanidins and P.distasonis combined(PPC)treatment can effectively alleviate high-fat diet(HFD)-induced AS.In this study,PPC treatment was found to significantly decrease atherosclerotic lesion,as well as alleviate the lipid metabolism disorder,inflammation and oxidative stress injury in ApoE^(-/-)mice.Surprisingly,targeted metabolomics demonstrated that PPC intervention altered the BA profile in mice by regulating the ratio of secondary BAs to primary BAs,and increased fecal BAs excretion.Further,quantitative polymerase chain reaction(qPCR)analysis showed that PPC intervention facilitated reverse cholesterol transport by upregulating Srb1 expression;In addition,PPC intervention promoted BA synthesis from cholesterol in liver by upregulating Cyp7a1 expression via suppression of the farnesoid X receptor(FXR)pathway,thus exhibiting a significant serum cholesterol-lowering effect.In summary,PPC attenuated HFD-induced AS in ApoE^(-/-)mice,which provides new insights into the design of novel and efficient anti-atherosclerotic strategies to prevent AS based on probiotics and prebiotics.