[Changes of bone morphogenetic protein-7 and inhibitory Smad expression in streptozotocin-induced diabetic nephropathy rat kidney].
The present study was designed to observe the expressions of bone morphogenetic protein-7 (BMP-7) and inhibitory Smads in kidney of rats with diabetic nephropathy (DN), and explore the possible mechanism of DN. Male Wistar rats weighing 180-220 g were single injected with streptozocin (STZ, 55 mg/kg body weight) for 2, 4, 8 and 16 weeks to induce DN. Blood glucose, kidney weight/body weight and 24-hour urine protein in the control and DN rats were examined; the expressions of BMP-7, Smad6 and Smad7 were detected by using immunohistochemical techniques, Western blot and real-time PCR. The results showed that blood glucose and 24-hour urine protein in DN rats were higher than that in the control rats and kidney weight/body weight was also elevated in DN rats, especially in 16-week STZ-induced rats. The expressions of BMP-7 and Smad6 proteins in DN rats were elevated, while BMP-7 mRNA expression was increased 2 weeks after STZ injection and decreased 16 weeks after STZ injection. The expressions of Smad7 protein and mRNA were elevated in DN rats 2 weeks after STZ injection and decreased 16 weeks after STZ injection. In addition, the expressions of transforming growth factor-beta1 (TGF-beta1) and collagen type I (COL-I) mRNA were increased in DN rats. These results suggest in the early stage of DN, increase in BMP-7 and inhibitory Smad expression may play a role in the feedback regulation and restrain the development of DN.
Yang
Qin
Q
Department of Pathophysiology, Guiyang Medical College, Guiyang, China. qinyang@gmc.edu.cn
Han
Bing
B
Xie
Ru-Jia
RJ
Cheng
Ming-Liang
ML
D000818:Animals; D055419:Bone Morphogenetic Protein 7 / Q000235:genetics / Q000378:metabolism*; D024042:Collagen Type I / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D003928:Diabetic Nephropathies / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism* / Q000473:pathology; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D051905:Smad6 Protein / Q000235:genetics / Q000378:metabolism*; D051906:Smad7 Protein / Q000235:genetics / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism
C525821:Bmp7 protein, rat; D055419:Bone Morphogenetic Protein 7; D024042:Collagen Type I; D012333:RNA, Messenger; D051905:Smad6 Protein; C497804:Smad6 protein, rat; D051906:Smad7 Protein; C497808:Smad7 protein, rat; D053773:Transforming Growth Factor beta1