ABSTRACT
Objective:To investigate the correlation between the promoter methylation level of Dickkopf-related protein 1 (DKK1) gene and diabetic microangiopaopathy complicated with osteoporosis.Methods:Patients with type 2 diabetes mellitus (T2DM) microangiopathopathy who were admitted to our hospital from Jan. 2019 to Dec. 2022 were collected as research objects, and divided into observation group (44 cases) and control group (58 cases) according to whether they were complicated with osteoporosis. Bone mineral density (BMD) of lumbar spine (L1-4) was measured, and bone metabolism indexes, including serum calcium, serum phosphorus, 25-hydroxy vitamin D3[25-hydroxy vitamin D3, 25- (OH) D3], PTH, C-terminal telopeptide of typeI collagen (CTX), procollagen of aminoterminal propeptide (PINP) and tartrate resistant acid phosphatase (TRACP) levels were detected; The promoter methylation level of DKK1 gene was determined.Results:The methylation level of DKK1 gene promoter in the observation group was 5.17%±0.73%, which was significantly higher than that in the control group (3.81%±0.61%), with statistical significance ( t=5.22, P<0.001). The 25- (OH) D3 level, PTH and lumbar bone density in the observation group were significantly lower than those in the control group, while the CTX and TRACP levels were significantly higher than those in the control group ( t was 5.58, 4.35, 4.12, 4.05 and 4.17, respectively, P<0.001). In all patients, the promoter methylation level of DKK1 gene was significantly positively correlated with CTX and TRACP ( r was 0.41 and 0.39, P was 0.006 and 0.027, respectively), and significantly negatively correlated with PTH and lumbar bone density ( r was -0.38 and -0.43, respectively). P=0.015 and 0.003, respectively). ROC curve analysis showed that the area under the curve of DKK1 methylation level to distinguish type 2 diabetes microangionopathy with and without osteoporosis was 0.841 (0.762-0.921), and the sensitivity and specificity were 86.4% and 72.4%, respectively. Conclusion:The methylation level of DKK1 gene promoter is associated with osteoporosis and bone metabolism in T2DM patients with microangiopathia.