Proanthocyanidin derived from the leaves of Vaccinium virgatum suppresses platelet‐derived growth factor‐induced proliferation of the human hepatic stellate cell line LI90

Aim: Hepatic stellate cell (HSC) proliferation plays a pivotal role in liver fibrogenesis, and agents that suppress HSC activation, including platelet‐derived growth factor (PDGF)‐induced HSC proliferation, are good candidates for antifibrogenic therapies. In this report, we use the LI90 HSC line to elucidate the antifibrogenic effects of proanthocyanidin derived from the leaves of Vaccinium virgatum. Methods: Proanthocyanidin (PAC) was extracted from the leaves of blueberry V. virgatum (BB‐PAC), grape seeds (GS‐PAC) and Croton lechleri (CL‐PAC). These extracts were examined for their effects on PDGF‐BB‐induced LI90 cell proliferation and DNA synthesis. Extracellular signal‐regulated kinase (ERK) and Akt phosphorylation and PDGF receptor‐β (PDGFR‐β) expression were evaluated by western blot analysis. Results: BB‐PAC potently suppressed PDGF‐BB‐induced proliferation and DNA synthesis of LI90 cells. BB‐PAC also suppressed PDGF‐BB‐induced DNA synthesis in primary cultured rat HSC. Moreover, GS‐PAC and CL‐PAC suppressed PDGF‐BB‐induced DNA synthesis in LI90 cells. In contrast, the monomeric PAC catechin and epicatechin and dimeric PAC procyanidin B2 only slightly suppressed PDGF‐BB‐induced DNA synthesis. Western blot analysis showed that BB‐PAC completely or partially inhibited PDGF‐BB‐induced ERK and Akt phosphorylation, respectively. In addition, BB‐PAC partially inhibited the PDGF‐BB‐induced degradation of PDGFR‐β. Conclusion: Our results suggest that BB‐PAC suppresses activated HSC by inhibiting the PDGF signaling pathway. In addition, these results provide novel findings that may facilitate the development of antifibrogenic agents.     

葡萄籽原花青素对实验性高脂血症兔血脂及血浆氧化低密度脂蛋白的影响

目的　探讨葡萄籽原花青素 (grape seed proanthocyanidin,GSP)对实验性高脂血症兔血脂及脂质过氧化的影响。方法　雄性新西兰兔 2 4只 ,随机分为 3组 :正常对照组 8只 ,饲喂标准颗粒饲料 ;模型组 8只 ,饲喂含 1%胆固醇的颗粒饲料 ;干预组 8只 ,饲喂含 1% GSP和 1%胆固醇的颗粒饲料。分别于实验前及实验的第 4 ,8,12周末空腹经耳中动脉采血 ,测血清总胆固醇 (TC)、三酰甘油 (TG)、高密度脂蛋白胆固醇 (HDL - c)、低密度脂蛋白胆固醇(L DL - c)以及血浆氧化低密度脂蛋白 (ox L DL )。结果　与模型组相比 ,GSP干预组的血脂无明显变化 (P>0 .0 5 ) ,但其血浆 ox L DL的水平明显下降 (P<0 .0 5或 0 .0 1)。结论　 GSP对血脂的影响并不显著 ,但可明显抑制血浆低密度脂蛋白的氧化     

原花青素的提取方法与药理作用研究进展

对天然原花青素的提取方法与药理作用进行综述。原青花素的提取方法主要包括有机溶剂提取法、超声提取法、酶提取法、超临界流体法。原花青素的药理作用包括调节免疫、抗炎、护肝降脂、保护肠道损伤、保护大脑功能、防治动脉硬化、抗紫外线活性、保护神经系统、保护视神经等。     

Investigation of the protective effects of proanthocyanidin and vitamin E against the toxic effect caused by formaldehyde on the liver tissue

We aimed to investigate of protective role of proanthocyanidin (PA) and vitamin E (vit E) against to toxic effect of formaldehyde (FA). Twenty‐eight Wistar albino rats were divided into four groups: control group, rats treated with FA intraperitoneal (i.p.) (10 mg/kg), FA + vit E intragastric (i.g.) (30 mg/kg), and FA + PA i.g. (100 mg/kg). We assayed superoxide dismutase (SOD), glutathione peroxidase (Gpx), myeloperoxidase (MPO) activity and levels of malondialdehyde (MDA) and total sialic acid (TSA) in liver. Liver tissue was taken in order to morphological analysis and hepatocytes apoptosis using terminal deoxynucleotidyl transferase dUTP nick‐end labeling (TUNEL) assay immunostaining. SOD decreased in FA and increased in FA + vit E and FA + PA (p < 0.05). Gpx didn't change in FA and increased in FA + PA (p < 0.05). No significant variation between the groups was found in MPO activity. MDA increased only in FA and decreased in FA + vit E and FA+PA (p < 0.05). TSA didn't alter in FA and FA + vit E but decreased in FA + PA (p < 0.05). Degeneration in hepatocytes and endothelial cells, cytoplasm losses, vacuolization, picnotic nuclei, and mononuclear cell infiltration were identified in FA. Degeneration in chromatin material, membrane damage in mitochondria and losses in mitochondrial cristae in hepatocytes were observed in FA. We found that partially recovery in liver as a result of FA + vit E and FA + PA. We have concluded that long term use should be investigated for complete explanation of PA's protective effects on FA toxicity. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1406–1415, 2015.     

Grape Seed Proanthocyanidin Extract Alleviates Arsenic-induced Oxidative Reproductive Toxicity in Male Mice

Objective To determine the ability of grape seed proanthocyanidin extract (GSPE) in alleviating arsenic-induced reproductive toxicity.
Methods Sixty male Kunming mice received the following treatments by gavage: normal saline solution (control); arsenic trioxide (ATO; 4 mg/kg); GSPE (400 mg/kg); ATO+GSPE (100 mg/kg);ATO+GSPE (200 mg/kg) and ATO+GSPE (400 mg/kg). Thereafter, the mice were sacrificed and weighed, and the testis was examined for pathological changes. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), heme oxygenase 1 (HO1), glutathione S-transferase (GST), NAD(P)H dehydrogenase, and quinone 1 (NQO1) expression in the testis was detected by real-time PCR. Superoxide dismutase (SOD), glutathione (GSH), total antioxidative capability (T-AOC), malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and reproductive indexes were analyzed.
Results ATO-treated mice showed a significantly decreased sperm count and testis somatic index and activity levels of SOD, GSH, and T-AOC than control group. Compared to the ATO-treated group, ATO+GSPE group showed recovery of the measured parameters. Mice treated with ATO+high-dose GSPE showed the highest level of mRNA expression of Nrf2, HO, NQO1, and GST.
Conclusion GSPE alleviates oxidative stress damage in mouse testis by activating Nrf2 signaling, thus counteracting arsenic-induced reproductive toxicity.     

A dynamic mechanical method to assess bulk viscoelastic behavior of the dentin extracellular matrix

ObjectivesTo develop a protocol for assessment of the bulk viscoelastic behavior of dentin extracellular matrix (ECM), and to assess relationships between induced collagen cross-linking and viscoelasticity of the dentin ECM.MethodsDentin ECM was treated with agents to induce exogenous collagen cross-linking: proanthocyanidins (PACs) from Vitis vinifera – VVe, PACs from Pinus massoniana - PMe, glutaraldehyde – (GA), or kept untreated (control). A dynamic mechanical strain sweep method was carried out in a 3-point bending submersion clamp at treatment; after protein destabilization with 4 M urea and after 7-day, 6-month, and 12-month incubation in simulated body fluid. Tan δ, storage (E’), loss (E”), and complex moduli (E*) were calculated and data were statistically analyzed using two-way ANOVA and post-hoc tests (α = 0.05). Chemical analysis of dentin ECM before and after protein destabilization was assessed with ATR-FTIR spectroscopy.ResultsSignificant interactions between study factors (treatment vs. time points, p < 0.001) were found for all viscoelastic parameters. Despite a significant decrease in all moduli after destabilization, PAC-treated dentin remained statistically higher than control (p < 0.001), indicating permanent mechanical enhancement after biomodification. Covalently crosslinked, GA-treated dentin was unaffected by destabilization (p = 0.873) and showed the lowest damping capacity (tan δ) at all time points (p < 0.001). After 12 months, the damping capacity of PMe and VVe groups decreased significantly. Changes in all amide IR resonances revealed a partial chemical reversal of PAC-mediated biomodification.SignificanceViscoelastic measurements and IR spectroscopy aid in elucidating the role of inter-molecular collagen cross-linking in the mechanical behavior of dentin ECM.     

Comparison of methods for proanthocyanidin extraction from pine (Pinus densiflora) needles and biological activities of the extracts

Flavonoids are known to be effective scavengers of free radicals. In particular, proanthocyanidins are flavonoids that possess cardiovascular protection, antioxidative activities, and immunomodulatory activities. Here, we evaluated proanthocyanidin contents in the total polyphenolic compounds of pine needle extracts prepared by hot water, ethanol, hexane, hot water-hexane (HWH), and hot water-ethanol (HWE). Analysis of each extract indicated that the ethanol extract contained the highest proanthocyanidin concentration. The HWH and hexane extracts also contained relatively high concentrations of proanthocyanidin. On the other hand, proanthocyanidin content analyses out of the total polyphenolic compounds indicated that the HWH extract contained the highest content. These results suggest that HWH extraction is a suitable method to obtain an extract with a high level of pure proanthocyanidins and a relatively high yield. The HWH extract possessed superior activity in diverse antioxidative analyses such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferrous ion chelating (FIC), and ferric-ion reducing power (FRAP) assays. In addition, upon assessing the effects of the pine needle extracts on macrophages (Raw 264.7 cell), the HWH extract exhibited the highest activity. In this study, we discerned an efficient extraction method to achieve relatively pure proanthocyanidins from pine needles and evaluated the biological functions of the resulting extract, which could potentially be used for its efficacious components in functional food products.     

黏膜溃疡散的药效学研究

目的观察黏膜溃疡散的抗炎、镇痛及对实验性口腔溃疡的治疗作用。方法采用大鼠实验性口腔溃疡、小鼠醋酸扭体及巴豆油致耳肿胀等模型,测定给药后溃疡面积的大小和耳肿胀度,观察扭体次数。结果黏膜溃疡散明显减小实验性口腔溃疡模型大鼠溃疡直径、减少醋酸致小鼠扭体的次数、抑制小鼠耳肿胀。结论黏膜溃疡散有明显的抗炎、镇痛作用,并对实验性口腔溃疡有明显的治疗作用。