木犀草素对STZ诱导的糖尿病肾脏的保护作用

目的:探讨木犀草素对糖尿病肾脏的保护作用及其可能机制。方法:雄性SD大鼠随机分为5组,即正常对照组、糖尿病模型组、木犀草素低、中、高剂量组,采用腹腔注射链脲佐菌素法建立糖尿病大鼠模型,生化方法测定血糖、尿蛋白、血及肾组织超氧化物歧化酶(SOD)、过氧化氢酶(CAT)的活性及肾组织丙二醛(MDA)的含量;W estern blotting检测肾皮质转化生长因子β1(TGF-β1)、纤溶酶原激活物抑制物-1(PAI-1)蛋白质水平;光镜观察肾组织形态改变。结果:与糖尿病模型组相比,木犀草素治疗组大鼠血糖水平明显降低(P0.01)、24 h尿蛋白明显减少(P0.01),血清及肾组织SOD、CAT活性升高(P0.01),肾组织MDA含量显著降低(P0.01),木犀草素治疗组肾皮质TGF-β1及PAI-1蛋白表达明显低于糖尿病模型组。结论:木犀草素对STZ诱导的糖尿病大鼠肾脏具有一定的保护作用,其机制可能与其抗氧化作用及降低肾组织TGF-β1、PAI-1的蛋白表达有关。

Protective effects of luteolin on STZ-induced diabetic kidneys

AIM: To explore the protective effects of luteolin on the diabetic kidneys. METHODS: Male Sprague-Dawley rats were randomly divided into 5 groups: normal control group, diabetic model group and the groups of diabetic rats treated with luteolin at a low dose, a middle dose and a high dose. The diabetic model was induced by a single intraperitoneal injection of streptozotocin (STZ,65 mg/kg). Blood glucose, urine protein, the activity of superoxide dismutase and catalase in serum and kidney, and the content of malonaldehyde(MDA) in kidney were analyzed by biochemical methods. Western blotting was used to detect the protein expression of transforming growth factor-β₁(TGF-β₁) and plasminogen activator inhibitor-1(PAI-1) in the renal cortex. The morphological changes of the renal tissues were observed under microscope. RESULTS: Compared with diabetic model group, luteolin significantly reduced the level of blood glucose (P<0.01), the content of urine protein (P<0.01) and MDA (P<0.01) in the kidneys, and increased the activity of superoxide dismutase and catalase (P<0.01) in serum and kidneys in the diabetic rats. The protein levels of TGF-β₁ and PAI-1 in the renal cortex were dramatically decreased as the rats were treated with luteolin. CONCLUSION: Luteolin may exert an important protective effect on diabetic kidneys by relieving oxidative stress and inhibiting the protein expression of TGF-β₁ and PAI-1 in the renal tissues of STZ-induced diabetic rats.