摘要
目的：芒果苷（MF）是从知母根提取出来的-种多元酚.本研究旨在探讨芒果苷对胰岛素抵抗和链脲霉素（STZ）引起的糖尿病动物模型的高血糖的影响.方法：通过多次皮下注射氢化可的松琥珀酸钠（HCSS）（70mg/kg）或单次静脉内注射STZ（130mg/kg）建立糖尿病模型.同时连续口服10天不同剂量（50,100和200mg/kg）的MF.腹腔注射胰岛素（0.5U/kg）后,收集不同时间的血糖数值来检测胰岛素抵抗.同时测定肾脏氧自由基吸收能力（ORAC）和超氧化物歧化酶（SOD）活性.建立体外实验,研究MF对α-葡萄糖苷酶的抑制能力.结果：口服芒果苷能够显著抑制由注射HCSS引起的胰岛素抵抗.STZ诱导的糖尿病症状也有所改善,包括空腹血糖,糖化血红蛋白,血浆甘油三酯,肝糖原,肾脏SOD和ORAC水平.体外实验证明芒果苷具有较强的α-葡萄糖苷酶抑制活性.结论：结果表明芒果苷能改善胰岛素抵抗和STZ诱导的糖代谢紊乱.芒果苷通过提高抗氧化能力,促进肝糖原合成,抑制α-葡萄糖苷酶活性发挥保护作用.
Objective： Mangiferin （MF） is a polyphenol isolated from the root of Anemarrhena asphodeloides Bge.. This study wasaimed to investigate the effects of MF on hyperglycemia in animal models of insulin resistance and streptozotocin（STZ）-induced diabetes. Methods： The diabetes mellitus model was established in mice by receiving a multiplehypodermic injection of hydrocortisone sodium succinate （HCSS） （70 mg/kg） or a single intravenous injection of STZ（130 mg/kg）. Meanwhile MF at different dosage （50, 100 and 200 mg/kg） were oral administrated for consecutive 10days. Data of blood glucose were collected at different time after intraperitoneal injection of insulin （0.5 U/kg） toinvestigate the insulin resistant. As well as the oxygen radical absorbance capacity （ORAC） and superoxide dismutase（SOD） activity of kidney were measured. The in vitro experiment was established to investigate the inhibitory capacity ofMF to α-glucosidase. Results： Oral administration of MF significantly prevented insulin resistance caused by HCSSinjection. STZ-induced diabetic symptoms were also improved, including fasting blood glucose, glycated hemoglobin,plasma triglycerides, hepatic glycogen, kidney SOD and ORAC level. The in vitro experiment demonstrated that MF hadpotent α-glucosidase inhibitory activity. Conclusion： The obtained results demonstrate that MF ameliorates insulinresistance and STZ-induced glucose metabolism disturbance. The MF exerts the protective effects through improving theantioxidant ability, promoting hepatic glycogen synthesis and inhibiting α-glucosidase activity.
