白藜芦醇抑制过氧化氢诱导的IPEC-J2细胞凋亡及其机制

为了研究白藜芦醇抑制过氧化氢诱导的IPEC-J2细胞凋亡及其机制,利用过氧化氢(Hydrogen peroxide,H_2O_2)建立IPEC-J2细胞凋亡模型,然后分别使用不同浓度的白藜芦醇(Resveratrol,Rel)对IPEC-J2细胞预处理,通过MTT、流式细胞术和蛋白质免疫印迹试验,检测白藜芦醇对H_2O_2诱导的IPEC-J2细胞凋亡的保护作用及其机制。结果表明:50μmol/L的白藜芦醇通过ERK1/2和AKT信号,可以明显抑制50μmol/L过氧化氢诱导的IPEC-J2细胞凋亡。     

水分胁迫对葡萄果实白藜芦醇合成相关基因表达的影响

为探究水分胁迫对葡萄果实白藜芦醇合成的影响,本研究以赤霞珠为试验材料,对其进行不同程度水分胁迫处理,测定葡萄果实白藜芦醇含量及白藜芦醇生物合成相关基因表达量。结果表明,葡萄果实进入转色期,PAL、4CL、STS基因随白藜芦醇合成而大量表达;不同水分胁迫处理均能增加葡萄果实白藜芦醇含量,同时提高白藜芦醇合成相关基因的表达量,不同水分胁迫处理间存在差异;水分胁迫对果实转色前期和后期PAL、STS基因表达的促进作用最为显著,但水分胁迫显著降低了CHS基因的表达量。相关性分析表明,白藜芦醇含量与PAL、STS基因的表达量呈显著正相关,表明水分胁迫主要通过诱导PAL、STS基因表达来增加果实白藜芦醇含量。本研究结果为进一步阐明葡萄白藜芦醇合成调控机制奠定了理论基础。     

白藜芦醇对氧化应激仔猪肝脏抗氧化酶、细胞因子mRNA表达及核因子E2相关因子2相关因子信号通路的影响

本试验旨在研究白藜芦醇(RES)对敌草快(diquat)诱导的氧化应激仔猪肝脏抗氧化、抗炎性能的影响。选用健康断奶仔猪30头,随机分为5组,对照组(CON组)和diquat组(DIQ组)饲喂基础饲粮,试验组(RES-10组、RES-30组、RES-90组)饲喂在基础饲粮中分别添加10、30、90 mg/kg RES的试验饲粮。于试验第15天清晨给DIQ组、RES-10组、RES-30组、RES-90组仔猪按照10 mg/kg BW剂量腹腔注射diquat建立氧化应激模型,CON组注射相同剂量灭菌生理盐水。试验期21 d。结果表明：与CON组相比,DIQ组肝脏超氧化物歧化酶1(SOD1)、超氧化物歧化酶2(SOD2)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶-1(GPX-1)的mRNA相对表达量均显著降低(P<0.05);肝脏白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)的mRNA相对表达量显著升高(P<0.05),而白细胞介素-10(IL-10)的mRNA相对表达量显著降低(P<0.05);肝脏Kelch样ECH关联蛋白1(...     

白藜芦醇对甲基乙二醛损伤BRL-3A细胞的抑制作用

为研究甲基乙二醛(MGO)对大鼠肝细胞BRL-3A细胞的损伤机制,在MGO存在的情况下,以50μmol/L白藜芦醇处理BRL-3A,分别用MTT法检测细胞活力;DNPH法检测细胞内Schiff base浓度;DCFH-DA荧光探针法检测ROS水平;以及脂质过氧化产物MDA含量的检测。结果表明,MGO导致细胞内Schiff base、ROS和MDA显著增加,诱导细胞发生氧化应激,白藜芦醇处理可有效改善MGO对细胞的损伤作用。     

白藜芦醇对体外培养的水牛卵丘细胞增殖活力及其相关基因mRNA表达的影响

【目的】研究白藜芦醇(resveratrol, RES)对水牛卵丘细胞体外培养过程中细胞增殖活力、激素分泌、卵丘扩展及抗凋亡和抗氧化能力的影响。【方法】用不同浓度(0(对照组)、1、10、20、30、40、50和60μmol/L)RES培养卵丘细胞,用CCK-8试剂盒测定细胞增殖活力,筛选最佳RES处理浓度及时间用于后续试验。用ELISA法测定培养液中卵丘细胞分泌的雌二醇(estradiol, E₂)和孕酮(progesterone, P₄)的含量,实时荧光定量PCR法测定卵丘细胞扩展、凋亡和抗氧化相关基因的相对表达量。【结果】与对照组相比,在体外培养24～36 h内,1、10和20μmol/L RES组水牛卵丘细胞的增殖活力均有升高趋势,10μmol/L RES处理36 h细胞活力最强,因此用于后续试验中细胞的处理。体外培养36 h时,10μmol/L RES组细胞增殖能力和E₂、P₄的分泌显著增加(P<0.05);10μmol/L RES组卵丘细胞扩展相关基因穿透素3(PTX3)、前列腺素...     

Resveratrol–cyclodextrin complex affects the expression of genes associated with lipid metabolism in bovine in vitro produced embryos

Antioxidants have been widely used during in vitro production to decrease the negative effect of reactive oxygen species. It was reported that the complex resveratrol–methyl β‐cyclodextrin (RV ‐CD ) improves resveratrol's stability and bioavailability and increases its antioxidant activity. This study evaluates the effect of RV ‐CD during in vitro oocyte maturation (IVM ) or in vitro embryo culture (IVC ) on developmental competence and quantitative changes in gene expression of developmental important genes. In experiment 1, RV ‐CD was added to IVM media and maturation level, embryo development and oocytes, cumulus cells, and blastocysts gene expression by RT ‐qPCR were examined. In experiment 2, presumptive zygotes were cultured in SOF supplemented with RV ‐CD and embryo development and blastocysts gene expression by RT ‐qPCR were studied. A group without RV ‐CD (control^?) and a group with cyclodextrin (control⁺) were included. No differences were found in cleavage rate or blastocyst yield between groups. However, the expression of LIPE was higher in blastocysts derived from oocytes treated with resveratrol compared with control groups (p  <  .05). Blastocysts produced by IVC with resveratrol showed that RV ‐CD could modify the expression of genes related to lipid metabolism (CYP 51A1 , PNPLA 2 and MTORC 1 ) compared with control groups (p  < .05). RV ‐CD in the IVM and IVC media could reduce accumulated fat by increasing lipolysis and suppressing lipogenesis of blastocysts.     

Stilbene Levels in the Tissue and Juice of Muscadine Grapes (Vitis rotundifolia Michx.)

Abstract

Stilbenes are secondary metabolites of a class of non-flavanoid phenolics found in certain species of Vitis. This class of compounds includes resveratrol and a resveratrol glucoside called piceid that exists in trans and cis forms. This study was undertaken to determine the cis and trans forms of both resveratrol and piceid in the skin, pulp, seeds, and juice of nine cultivars of muscadine grapes and three cultivars of Vitis labruscana. Juice samples of the muscadine cultivars ‘Fry’, ‘Hunt’, ‘Magnolia’, ‘Watergate’, ‘Carlos’, ‘Noble’, and ‘Sweet Jenny’, and the V. labruscana cultivars ‘Albermarle’, ‘Miss Blanc’, ‘MidSouth’ and ‘Miss Blue’ were harvested at the full ripe stage and divided into two sub-samples. One subsample was used to extract juice and the other was divided into skins, pulp, and seeds. Sample analysis was performed using HPLC with a UV detector. Sample chromatagrams were compared with those of known standards for quantification. ‘Carlos’ and ‘Magnolia’ had the greatest total stilbene concentration in skin tissue and had bronze skin containing higher concentrations of total stilbenes than any of the black-skinned cultivars tested. Only one bronze skin cultivar, ‘Sweet Jenny’, had lower stilbenes than the dark skin cultivars. Piceid, cis piceid and resveratrol were found in the skins of all cultivars. ‘Carlos’ ‘Magnolia’, ‘Fry’ and ‘Albermarle’ muscadines contained cis resveratrol in the skins of the fruit. ‘Watergate’ was the only cultivar in which resveratrol was detected in seed tissue. ‘Sweet Jenny’ had the highest levels of cis piceid in seed tissue. ‘Albermarle’, ‘Carlos’ and ‘Sweet Jenny’ had significantly greater levels of cis picied in pulp tissue than all other cultivars.     

白藜芦醇与牛血清白蛋白相互作用的研究

采用荧光猝灭光谱、同步荧光光谱和紫外-可见吸收光谱,研究了白藜芦醇与牛血清白蛋白(BSA)的相互作用。结果表明白藜芦醇对BSA有较强的荧光猝灭作用,荧光猝灭机理属于二者形成复合物所引起的静态猝灭和非辐射能量转移;根据不同温度下防己诺林碱对BSA的荧光猝灭作用,利用Stern-Volmer方程处理实验数据,得到白藜芦醇与BSA之间的结合常数KA为6.11×104(25℃)、4.46×104(35℃)和3.84×104(45℃)。根据F rster非辐射能量转移理论,求出了白藜芦醇与BSA之间的结合距离为2.36 nm(25℃)、2.73 nm(35℃)和2.48 nm(45℃)。通过计算热力学参数,可知该药物与牛血清白蛋白的相互作用是一个吉布斯自由能降低的自发过程,且二者之间的主要作用力类型为疏水作用力,同时用同步荧光光谱探讨了白藜芦醇对BSA构象的影响。     

葡萄白藜芦醇合酶基因cDNA克隆及原核表达

从贝达葡萄中提取总RNA,采用RT-PCR方法,克隆到了白藜芦醇合酶(resveratrol synthase,RS)基因的全长cDNA。将其与圆叶葡萄(Vitis rotundifolia)、华东葡萄(Vitis pseudoreticulata)、河南毛葡萄(Vitis ficifolia)、河岸葡萄(Vitis vulpine)、酿酒葡萄(Vitis virufera)、羊蹄甲(Bauhinia)、花生(Arachis hvpogaea)、虎杖(Polygonum cuspiaatum)、大黄(Rheum officinale)进行氨基酸同源性比对,结果表明:分离的RS基因与其他葡萄的RS基因编码的氨基酸同源性达到97%以上,与其他属的RS基因编码的氨基酸同源性达到64%以上。生物信息学分析表明,该蛋白分子量为43kD,等电点pI=6.2,包含392个氨基酸残基。将RS的全长cDNA插入到表达载体pET28a中构建重组表达质粒pET28a-RS,转化大肠杆菌BL21,SDS-PAGE电泳检测结果表明,以30℃、0.5mmol.L-1IPTG诱导4h时该基因表达效果最好,诱导产物为1个约43kD的蛋白,为...