Objective To comparatively study anti-free radical and cytoprotective effects of quercetin(Q)and its monoglucoside isoquercetin(I),diglucoside rutin(R),which differs only in glycosyl-substitution at C-3 position of th...Objective To comparatively study anti-free radical and cytoprotective effects of quercetin(Q)and its monoglucoside isoquercetin(I),diglucoside rutin(R),which differs only in glycosyl-substitution at C-3 position of the molecules,using anoxia/hypoglycemia-induced cell injury model and thereby to explore the structure-effect relationship thereto.Methods The cell injury model was established by HEK293 cells cultured in vitro with Na2S2O3 plus sugar-free Earle's fluid as incubation medium.Cell survival rate(CSR),total antioxidant capacity(TAC),SOD and LDH levels were determined.The effect intensity of the 3 flavonoids was compared by means of IC50,the concentration required to achieve 50% inhibition of the changes in the above indices in injured cells.Results Q,I and R all concentration-dependently elevated CSR,TAC and SOD and reduced LDH level.The all of IC50s for the above indices were ranked in order of IC50,Q<IC50,I<IC50,R,namely,the effect intensity should be Q>I >R.Conclusions The 3 structurally similar flavoloids all have significant and concentration-dependent anti-free radical and cyto-protective effects with the intensity being in order of aglycone>monoglucoside>diglucoside;the substitution of-OH by sugar group at C-3 position of flavoloids and increase in the sugar-substituent number are associated with the effect intensity reduced;namely,the intensity of these effects of flavonoids is negatively related the substutution by sugar group at C-3 position.展开更多
为研究低氧环境对大鼠胃肠线粒体呼吸链复合物活性和自由基代谢的影响,将雄性 Wister 大鼠分别暴露于模拟5000 m 海拔进行4,24,72 h 的低氧处理.取小肠和胃组织,采用分光光度法测定线粒体呼吸链酶复合物 CⅠ~CⅣ活性,检测线粒体超氧化...为研究低氧环境对大鼠胃肠线粒体呼吸链复合物活性和自由基代谢的影响,将雄性 Wister 大鼠分别暴露于模拟5000 m 海拔进行4,24,72 h 的低氧处理.取小肠和胃组织,采用分光光度法测定线粒体呼吸链酶复合物 CⅠ~CⅣ活性,检测线粒体超氧化物歧化酶（SOD）活性及丙二醛（MDA）的含量.结果表明,模拟高原低氧暴露4,24 h 可引起胃肠组织中线粒体呼吸链四种复合酶的活性明显降低（P 〈0.01）,而在72 h 后恢复为接近对照组水平（P 〉0.05）.低氧处理后胃肠组织的线粒体 SOD 活性明显低于对照组（P 〈0.01）,MDA 含量高于对照组（P 〈0.01）.因此,高原低氧可抑制大鼠胃肠线粒体呼吸链组分的酶活性,该效应可能与低氧的直接作用和由此引起的氧化应激损伤有关.展开更多
文摘Objective To comparatively study anti-free radical and cytoprotective effects of quercetin(Q)and its monoglucoside isoquercetin(I),diglucoside rutin(R),which differs only in glycosyl-substitution at C-3 position of the molecules,using anoxia/hypoglycemia-induced cell injury model and thereby to explore the structure-effect relationship thereto.Methods The cell injury model was established by HEK293 cells cultured in vitro with Na2S2O3 plus sugar-free Earle's fluid as incubation medium.Cell survival rate(CSR),total antioxidant capacity(TAC),SOD and LDH levels were determined.The effect intensity of the 3 flavonoids was compared by means of IC50,the concentration required to achieve 50% inhibition of the changes in the above indices in injured cells.Results Q,I and R all concentration-dependently elevated CSR,TAC and SOD and reduced LDH level.The all of IC50s for the above indices were ranked in order of IC50,Q<IC50,I<IC50,R,namely,the effect intensity should be Q>I >R.Conclusions The 3 structurally similar flavoloids all have significant and concentration-dependent anti-free radical and cyto-protective effects with the intensity being in order of aglycone>monoglucoside>diglucoside;the substitution of-OH by sugar group at C-3 position of flavoloids and increase in the sugar-substituent number are associated with the effect intensity reduced;namely,the intensity of these effects of flavonoids is negatively related the substutution by sugar group at C-3 position.
文摘为研究低氧环境对大鼠胃肠线粒体呼吸链复合物活性和自由基代谢的影响,将雄性 Wister 大鼠分别暴露于模拟5000 m 海拔进行4,24,72 h 的低氧处理.取小肠和胃组织,采用分光光度法测定线粒体呼吸链酶复合物 CⅠ~CⅣ活性,检测线粒体超氧化物歧化酶（SOD）活性及丙二醛（MDA）的含量.结果表明,模拟高原低氧暴露4,24 h 可引起胃肠组织中线粒体呼吸链四种复合酶的活性明显降低（P 〈0.01）,而在72 h 后恢复为接近对照组水平（P 〉0.05）.低氧处理后胃肠组织的线粒体 SOD 活性明显低于对照组（P 〈0.01）,MDA 含量高于对照组（P 〈0.01）.因此,高原低氧可抑制大鼠胃肠线粒体呼吸链组分的酶活性,该效应可能与低氧的直接作用和由此引起的氧化应激损伤有关.
