Hawthorn Leaves Flavonoids Of Stz-dn Rats Treated With The Effect And Mechanism Of The Study

Objective To investigate the treatable effects of hawthorn leaves flavonoids on diabetic nephropathy which is induced by STZ (STZ-DN) of rat kidney and its mechanism. Methods Making rat model of type 2 diabetes with high-fat high-sugar feeding and streptozotocin iv(streptozotocin, STZ). 48 wistar rats were randomly divided into normal control group, STZ-DN model control group and hawthorn leaves flavonoids treatment group (FHL group). 12 weeks after treatment with hawthorn leaves flavonoids, renal tissue MDA content, SOD activity were detected with spectrophotometric determination, and TGF-β1, BMP-7 and Smad-4 expression of the mRNA were assayed with RT-PCR semi-quantitative methods. At the same time the blood glucose, blood lipids and renal function were observed. Also BUN (blood urea nitrogen, BUN), creatinine (blood creatinine, BCr) and other relevant targets were observed and compared with the normal and STZ-DN model group. Results 1. The blood glucose, BUN, BCr and urine protein of STZ-DN group were significantly increased (p <0.01); 2. Hawthorn leaves flavonoids can significantly reduce the STZ-DN rats blood glucose, blood lipids, urinary protein (p <0.05 ), and improve renal function; 3. Hawthorn leaves flavonoids can significantly enhance the activity of SOD in renal tissue in rats (p <0.05), with a significant reduction in rat renal tissue MDA levels (p <0.01); 4. TGF-β1, Smad-4 expression of the mRNA in the kidney of the STZ-DN group rat wre significantly higher than normal group (p <0.01), while the hawthorn leaves flavonoids treatment group were significantly lower than the STZ-DN control group (p <0.05); 5. There was a significant reduction of mRNA expression of BMP-7 (p <0.01) in the renal tissue of STZ-DN rats than the normal control group, while the hawthorn leaves flavonoids treatment group increased significantly than the STZ-DN rats (p <0.05); 6. Relevant analysis showed that there was a significant positive correlation (r = 0.991, P <0.01) between the expression of TGF-β1 mRNA and the expression of Smad-4 mRNA in the kidney of the rats; but BMP-7 mRNA expression and Smad-4 mRNA expression was negatively correlated (r =- 0.994, P <0.01). Conclusion TGF-β1 / BMP-7 participate in the renal injury in diabetes by increasing the expression of Smad-4. Hawthorn leaves flavonoids can increase the expression of BMP-7, reduce TGF-β1, Smad-4 expression in TGF-β/ Smad signaling pathways , and thus to treat the STZ-DN.