柿叶不同有效部位对链脲佐菌素致2型糖尿病大鼠糖代谢的影响

Effect of different effective parts of persimmon leaves on glucose metabolism in rats with type 2 diabetes mellitus induced by streptozotocin

目的研究柿叶不同溶剂萃取部位对2型糖尿病大鼠糖代谢的影响,以寻找柿叶降血糖作用的有效部位。方法雄性SD大鼠随机选择8只作为正常对照组,其余72只高脂高糖饲料喂养1个月后,腹腔注射链脲佐菌素(streptozotocin,STZ)30 mg/kg,建立2型糖尿病模型。将造模成功的大鼠随机分为模型组、盐酸二甲双胍组(0.11 g/kg)、石油醚萃取物组、二氯甲烷萃取物组、乙酸乙酯萃取物组和萃余物组,连续灌胃给药28 d(对照组、模型组灌胃等体积蒸馏水),1次/d。于给药前及给药7、14、21、28 d测定各组体重及空腹血糖值(fasting blood glucose,FBG),末次给药后眼眶取血测定糖化血红蛋白(glycosylated hemoglobin,Hb A1c)、血清胰岛素(fasting serum insulin,FINS),计算胰岛敏感指数(insulin sensitivity index,ISI)和稳态模型评估法(homeostasis model assessment,HOMA)计算胰岛素抵抗(Homa insulin resistance,HOMA-IR)指数。结果 (1)与模型组比较,柿叶二氯甲烷萃取物及萃余物均能够降低FBG、Hb A1c、FINS、HOMA-IR指数,并升高ISI,差异均有统计学意义(P<0.05);(2)二氯甲烷萃取物组在给药7、14 d后FBG及末次给药后Hb A1c、FINS较盐酸二甲双胍组无统计学差异,但Homa-IR指数、ISI与其比较有统计学差异(P<0.05)。结论柿叶二氯甲烷萃取物可能是柿叶降血糖的主要药效部位。

Objective To explore the effect of different extracts of persimmon leaves on glucose metabolism in rats with type 2 diabetes mellitus,so as to find the effective part of persimmon leaves with antidiabetics effects.Methods 8 male SD rats were randomly selected as the normal control group,the rest were intragastrical（ig） administered with high fatty and sugar diet for 1 month,and type 2 diabetic rat model was established by intraperitoneal injection streptozotocin（STZ） 30 mg/kg.Rats with type 2 diabetes mellitus were randomly divided into model group,metformin hydrochloride（0.11 g/kg） group,and persimmon leaves extracts groups of petroleum ether,dichloromethane,ethyl acetate,and raffinate.All animals were ig administered once daily for 28 days（the control group and model group were ig administered equal volume of distilled water）.Weight and fasting blood glucose（FBG） were determined before treatment and after treated 7,14,21 and 28 days.After the last administration,the blood samples were collected to measure the glycosylated hemoglobin（Hb A1c） and fastings erum insulin（FINS）,and insulin sensitivity index（ISI） and Homa insulin resistance（HOMA-IR） index were calculated.Results（1） Compared with model group,both dichloromethane extract group and raffinate extract group could significantly reduce the indexes of FBG,Hb A1 c,FINS,HOMA-IR and increase ISI index（P〈0.05）;（2） Compared with metformin hydrochloride group,differences of FBG in dichloromethane extract group after treated 7,14 days,and Hb A1 c and FINS in that group after the last administration had no statistical significance,but differences of HOMA-IR and ISI between two groups were statistically significant（P〈0.05）.ConclusionsDichloromethane extracts may be the main effective part of persimmon leaves with antidiabetics effects.