【摘要】 目的:观察亮氨酸溶液对四氧嘧啶糖尿病小鼠模型血糖、糖耐量及血液、脑组织生化指标的干预作用。方法:实验于2005-12/2006-01在右江民族医学院生物化学实验室完成。选择健康雄性小白鼠40只,按随机数字表法分为4组,即亮氨酸1mg/d组、亮氨酸5mg/d组、模型组及正常对照组,每组10只。造模前测定2次空腹血糖。亮氨酸1mg/d组、亮氨酸5mg/d组、模型组用四氧嘧啶水溶液腹腔注射复制拟糖尿病模型,空腹血糖在12mmol/L以上为造模成功。测定造模后2,3,5,9,15,17,22d空腹血糖;并在第22天做治疗前糖耐量实验,测定空腹、葡萄糖灌胃后30min,2h血糖水平。亮氨酸1,5mg/d组分别用的10g/L的亮氨酸水溶液0.1mL(+0.4mL蒸馏水)和0.5mL水溶液灌胃,模型组和正常对照组用0.5mL蒸馏水灌胃,1次/d,连续7d。实验过程中,测定造模前、后空腹血糖及亮氨酸治疗前、治疗7d后的血糖水平;测定治疗7d后各组小鼠血清谷丙转氨酶活性、尿素、三酰甘油、总胆固醇含量及大脑匀浆乙酰胆碱酯酶活性、超氧阴离子自由基O2-浓度和清除率、蛋白质含量。结果:纳入40只小鼠,分为4组,每组10只。治疗7d后糖耐量实验进入结果分析33只;治疗7d后血清、脑组织生化指标进入结果分析均为35只。①各组小鼠造模前、后空腹血糖及亮氨酸治疗前、治疗7d后的血糖水平比较:各组小鼠造模前两次空腹血糖水平相比差异均无显著性意义(P>0.05),造模后第2,3,5天,模型组空腹血糖水平显著高于其余各组(P<0.01～0.05)。灌服葡萄糖后30min,亮氨酸1,5mg/d组、模型组小鼠的血糖水平显著高于正常对照组(P<0.01),而且2h时仍处于较高水平。亮氨酸治疗7d后,灌胃葡萄糖后2h亮氨酸1,5mg/d组的血糖已有明显下降,特别是亮氨酸5mg/d组下降最明显。②各组小鼠亮氨酸治疗7d后血清生化指标比较:亮氨酸1,5mg/d组、模型组小鼠的血清尿素水平均显著高于正常对照组(P<0.05～0.01),以亮氨酸5mg/d组最高。模型组小鼠的血清谷丙转氨酶活性显著高于亮氨酸1,5mg/d组(P<0.05～0.01),以亮氨酸5mg/d组最低。③各组小鼠亮氨酸治疗7d后脑匀浆生化指标比较:亮氨酸1mg/d组小鼠的脑匀浆乙酰胆碱酯酶活性显著高于亮氨酸5mg/d组和正常对照组(P<0.05～0.01)。模型组小鼠的O2-清除率低于亮氨酸1,5mg/d组(P<0.05)。结论:四氧嘧啶糖尿病模型小鼠的空腹血糖和糖耐量均出现异常;血清尿素含量及谷丙转氨酶活性升高;脑组织氧自由基清除率下降。亮氨酸能够改善四氧嘧啶糖尿病小鼠的上述症状,其中亮氨酸5mg/d剂量组的治疗作用优于亮氨酸1mg/d剂量组。更多还原

【Abstract】 AIM: To study the interfered effects of leucine oral liquid on the blood glucose, sugar tolerance, and blood and cerebral tissue biochemical indexes in diabetic mice induced by alloxan. METHODS: The experiment was conducted in the Biochemical Laboratory of Youjiang Medical College for Nationalities between December 2005 and January 2006. Forty healthy male mice were selected and randomly divided into 4 groups: treatment 1 group, treatment 2 group, model group and control group with 10 mice in each group. The fasting blood glucose was detected for twice before modeling. Mice of the former three groups were poisoned with alloxan liquid by intraperitoneal injection to make models of diabetes; the animals with fasting blood glucose of 12 mmol/L or above were regarded as successful models. The fasting blood glucose was measured at day 2, 3, 5, 9, 15, 17 and 22 after modeling, respectively; and the sugar tolerance, fasting blood glucose and blood glucose 30 minutes and 2 hours after infused glucose were detected at day 22 before treatment. Animals of treatment 1 and treatment 2 groups were respectively infused 10 g/L leucine oral liquid 0.1 mL (+0.4 mL distilled water) and 0.5 mL liquid into stomach; the model group and control group were given equal distilled water once daily for 7 days. During the experiment, fasting blood glucose before and after modeling, and blood glucose level before and 7 days after treatment with leucine were determined; and alanine aminotransferase (ALT) activity, urea content, triglyceride (TG) and total cholesterol (TC) and acetylcholine esterase (ACE) activity, density and clearance of oxygen free radical O2- and protein content in brain homogenate of mice in each group were determined after 7 days treatment.RESULTS: Forty mice were included, which were divided into 4 groups with 10 mice in each group. Thirty-three mice entered the result analysis in the sugar tolerance experiment after 7 days of treatment; serum and cerebral tissue biochemical indexes of 35 mice were involved in the result analysis after 7 days treatment. ①Comparison of the fasting blood glucose before and after modeling and blood glucose level before and 7 days after treatment with leucine: There was no significant difference in the fasting blood glucose in the twice determination before modeling among each group (P > 0.05). But the blood sugar of the model group was obviously higher than the other three groups at day 2, 3, 5 after modeling (P < 0.01-0.05). The blood glucose level of the treated 1group, treated 2 group and model group were markedly higher than the control group after glucose infused for 30 minutes (P < 0.01), and still higher than the normal level after 2 hours. After 7 days treatment with leucine, the blood glucose levels after infused glucose for 2 hours of the two treatment group were decreased, especially the treatment 2 group. ②Comparison of serum biochemical indexes in each group: Urea in serum of the three model groups was all significantly higher than the control group (P < 0.05-0.01), but that in treatment 2 was the highest. ALT activity in serum of the model group was significantly higher than the two treatment groups (P < 0.05-0.01), and the treatment 2 was the lowest. ③Comparison of biochemical indexes of brain homogenate in each group: ACE activity in the treatment 1group was higher than the treatment 2 and control groups (P < 0.05-0.01). The clearance of O2- in the model group was lower than the two treatment groups (P < 0.05). CONCLUSION: Abnormal fasting blood glucose and sugar tolerance are found in the diabetic mice models induced by alloxan; urea in serum and ALT activity are increased and the clearance of oxygen free radical is decreased. Treating diabetes induced by alloxan with leucine can improve the symptoms mentioned above, and 5 mg per day has better curative effect than 1 mg per day.更多还原