Inactive matrix Gla protein in relation to diabetic retinopathy in type 2 diabetes

Background and Aims The contribution of inactive Matrix Gla protein (MGP) to ectopic vascular calcification associated with type 2 diabetes mellitus (T2DM) is well recognized. However, its role in diabetic microvascular complications remains unknown. The study aim was to identify any association between inactive MGP and diabetic retinopathy (DR). Its relation to insulin resistance was also explored. Methods The study included 90 participants, 65 Type 2 diabetic patients (25 without DR and 40 with DR) and 25 healthy controls. Serum inactive MGP was measured using ELISA. HOMA-IR was also assessed. Results Inactive MGP was significantly higher in both diabetic groups compared to controls ( P < 0.001), as well as in Type 2 diabetic patients with retinopathy compared to Type 2 diabetes without retinopathy ( P = 0.002). Inactive MGP was positively correlated with HbA1c, HOMA-IR, LDL-C and triglycerides ( P < 0.001), and negatively correlated with HDL-C ( P = 0.008) and eGFR ( P < 0.001). Logistic Regression Analysis showed that inactive MGP was one of the most associated factors with DR. Conclusions Inactive MGP was found to be related to DR, insulin resistance and other dysmetabolic risk factors. These findings highlight that inactive MGP may be a significant contributor to the pathogenesis, evolution, and progression of DR.