摘要
目的 研究醛糖还原酶在糖尿病肾病发生、发展中的作用.方法 健康雄性8周龄野生型C57BL/6小鼠(WT,n=6)、醛糖还原酶基因敲除型C57BL/6小鼠(KO,n=6)和醛糖还原酶双转基因型C57BL/6小鼠(BT,n=6)腹腔注射40μg/g链脲佐菌素,诱导糖尿病模型.另18只小鼠(每种品系各6只)注射枸橼酸盐缓冲液,作为对照.17周后测定体重、肾重、血糖、血清甘油三酯、胆固醇、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇、尿素氮、肌酐、肾小球滤过率、尿白蛋白等指标.采用过碘酸雪夫染色观察肾小球组织形态学变化,应用Western blot和免疫组织化学法检测肾皮质中胶原蛋白Ⅳ和转化生长因子-β1蛋白表达量,选用Pep Tag非放射性蛋白激酶C检测方法检测肾皮质细胞质和细胞膜中蛋白激酶C活性.多组间数据比较采用单因素方差分析.结果 醛糖还原酶基因敲除显著改善了糖尿病小鼠的生理生化指标、肾皮质、肾小球组织形态以及肾功能.糖尿病KO小鼠和糖尿病BT小鼠尿白蛋白分别较WT小鼠下降了43%[分别为(1.49±0.26)和(2.62±0.34)mg/g肌酐,F=20.8,P＜0.01]和48%[分别为(1.36±0.12)和(2.62±0.34)mg/g肌酐,F=20.8,P＜0.01].同时,醛糖还原酶基因缺失亦抑制了高糖对肾皮质蛋白激酶C和转化生长因子-β1的激活.结论 醛糖还原酶基因缺失显著改变了糖尿病肾病的进程,抑制醛糖还原酶可能有助于糖尿病肾病的防治.
Objective To study the roles of aldose reductase in the development of diabetic nephropathy using mouse models which were deficient for aldose reductase (AR). Methods Eight-weekold homozygous male AR-knockout (KO), bitransgenic (BT) and wild-type (WT) background C57BL/6 mice were treated with or without 40 μg/g streptozotocin by intraperitoneal injection. After 2 weeks, blood glucose was measured and hyperglycemia was confirmed. Diabetic and control mice were further maintained for 17 weeks,then sacrificed. Body weight, kidney weight, serum glucose, triglyceride, cholesterol, lowdensity lipoprotein cholesterol, high-density lipoprotein cholesterol, blood urea nitrogen, serum creatinine,glomerular filtration rate and urinary albumin parameters were determined. PAS staining was performed for kidney histological analyses. Western blot and immunohistochemistry were used to determine the expression of collagen Ⅳ and transforming growth factor-beta1 ( TGF-β1). Protein kinase C (PKC) activities for the cytoplasm and cell membrane fractions of the renal cortex were assayed with the kit of PepTag(R) Assay for non-radioactive detection of PKC. One-way ANOVA was used for multiple comparisons. Results In comparison with the diabetic mice with normal aldose reductase activity, most serum and urinary parameters as well as renal histological and functional parameters were significantly improved in diabetic mice deficient in aldose reductase. For instance, loss of AR in the KO mice results in 43% reduction in urine albumin ( ( 1.49 ± 0. 26 ) vs (2. 62 ± 0. 34 ) mg/g creatinine, F = 20. 8, P ＜ 0. 01 ) whereas a 48% reduction was resulted in the BT mice ((1.36 ±0. 12) va (2.62 ±0.34) mg/g creatinine, F =20.8, P ＜0.01).Further, aldose reductase deficiency prevented hyperglycemia-induced activation of PKC and TGF-β1.Conclusion AR contributes to the development of diabetic nephropathy in vivo. The inhibition of AR may be beneficial for the prevention and treatment of the disease.
出处
《中华糖尿病杂志》
CAS
2010年第5期-,共8页
CHINESE JOURNAL OF DIABETES MELLITUS
基金
国家自然科学基金，国家重大科技研究计划
