Abstract：Objective To investigate the relationship between serum bone morphogenetic protein-2 (BMP2), bone morphogenetic protein7 (BMP7) levels and calcium and phosphorus metabolism in patients with diabetic nephropathy. Methods The clinical data of 126 patients with diabetic nephropathy admitted to Xidian group hospital from November 2016 to November 2018 were analyzed retrospectively. Patients were divided into 5 groups, namely CKD1(n=22),CKD2(n=21),CKD3(n=27),CKD4(n=31),and CKD5(n=25) according to different stages of chronic kidney disease(CKD). Meanwhile, 36 cases of healthy individuals were set as control group. Serum BMP2, BMP7,serum phosphorus,serum calcium,creatinine(Scr),and parathyroid hormone(iPTH) were measured, and the relationship between serum BMP2 and BMP7 and calcium and phosphorus metabolism was also analyzed. Results ① Serum phosphorus, serum calcium, Scr, iPTH, BMP2 and BMP7 levels had no difference among patients in the control group and CKD1-2(P>0.05). The serum calcium and serum BMP7 levels of CKD4 were significantly lower than those of the control group(P<0.05). Patients in the CKD3 had elevated serum Scr, iPTH and BMP2 levels and decreased serum BMP7 levels(P<0.05). Patients in the CKD4 and CKD5 had elevated serum phosphorus, Scr, iPTH and BMP2 levels and decreased calcium and BMP7 levels(P<0.05). ② Pearson product correlation analysis showed that serum BMP2 was positively correlated with serum phosphorus, Scr and iPTH, and negatively correlated with serum calcium(P<0.05). ③ Multivariate stepwise regression analysis showed that serum phosphorus, serum calcium, Scr and iPTH were all related factors affecting serum BMP2 and BMP7 levels in patients with diabetic nephropathy(P<0.05). Conclusions Patient with CKD stage above three has elevated BMP2 and decreased BMP7, which is significantly correlated to the calcium and phosphorus metabolism, because the serum BMP2 is negatively correlated with serum calcium, and BMP7 is negatively correlated with serum phosphorus, Scr and iPTH.
