Investigation On Periostin’s Expression And Its Regulatory Mechanism In The Renal Tissue Of Diabetic Mouse

Objective： Diabetic nephropathy(DN), named also as diabeticglomerulosclerosis， is the most common and severe microvascularcomplication of diabetic mellitus(DM).The mortality of DM complicated DNis30times higher than non complications. The early symptom isn’t obviousand is paid no enough attention. Quite a few DN patients are awared when itshows overt albuminuria or obvious edema. However, there is short ofeffective methods to control the development. Therefore, it is very importantto recognize the character in early DN and take favourable measures toprevent renal complications. Periostin，an important extracellular matrixprotein excreted by osteoblast and its precursor cell, named also asosteoblast-speific factor2(OSF-2), expresses specifically in periosteum andperidontal membrane. Recent studies have found, periostin plays importantroles in tumor invasion, fracture healing, myocardial reconstruction,scarrecovery and so on. The characteristically pathological change of DN is theglomerular sclerosis induced by the extracellular matrix accumulation.Therefore we speculate that periostin as an important extracellular matrixprobably participates in the occurrence and development of DN. By means ofbiochemical indicator measurement, hematoxylin-eosin(HE) and Massonstaining, immunohistochemistry assay and western blotting, we observed renalperiostin expression in diabetic mouse or glomerular mesangial cells, thenanalyzed the relation of TGF-β1to periostin, which was helpful to explorenew approach that discovers and treats diabetic nephropathy early.Methods：30healthy CD-1mice was established DM models withnephrectomy and intraperitoneal injection streptozotocin(STZ). And the modelwas considered to be successful when the fasting blood glucose exceeded13.9mmol/L or randomly blood glucose exceeded16.7mmol/L and urinary glucose (3+)～(4+) after72hours of STZ injection. The blood and24-hoururine were collected to detect serum creatinine(Scr) and urine protein. Thekidney tissue of the normal and DM model mice were made to paraffin sectionand observed pathological changes in light microscope. Otherwise, theexpression of periostin in kidney tissue was detected throughimmunohistochemistry. The immunohistochemistry results was analyzedthrough Image-Pro Plus(PPI) system. The mouse mesangial cell was culturedin vitro and stimulated with high glucose, TGF-β1and TGF-β1neutraliaingantibody. The mesangial cells of every group were collected to extract proteinafter4h and12h. The expression of periostin in mesangial cell was detectedwith Western Blot, and the result was analyzed through ImageJ system. Allthe data were analyzed by SPSS13.0system, and P＜0.05was considered tohave statistical significance.Result: The urine protein and serum creatinine of DM group were higherthan normal control group(P＜0.05). And also the kidney pathologicalchanges was significant in DM, the immunohistochemistry showed thatexpression of periostin was significantly higher than normal control group (P＜0.05). The expression of periostin was advanced by the stimulus of highglucose and TGF-β1in mesangial cells, and the express of stimulated4h washigher than12h. Moreover, TGF-β1neutraliaing antibody could lower theexpression of periostin(P＜0.05).Conclusion: In high glucose, the expression of periostin heightened, andpositive correlation with the renal lesions and urine protein. The expression ofperiostin is related to TGF-β, and it can be inhibitted by TGF-β neutraliaingantibody.