[Selenoprotein P in type 2 diabetes mellitus and its association with insulin resistance]

To explore the relationship between selenoprotein P (SEPP) and insulin resistance in subjects with normal glucose tolerance and type 2 diabetes mellitus.

A total of 156 subjects with newly onset diabetes and 64 subjects with normal glucose tolerance were enrolled. Fasting plasma glucose (FPG), fasting insulin (FIN), lipid profile and SEPP level were measured and height, weight and blood pressure were recorded. Insulin resistance index was calculated by homeostatic model assessment (HOMA-IR).

The SEPP level was significantly higher in obese and non-obese diabetic groups than control group ((4.43 ± 1.95), (3.01 ± 1.20) vs (2.34 ± 2.30)mmol/L, both P < 0.01). The SEPP level was significantly higher in obese subgroup of diabetic group than non-obese subgroup (P < 0.05). The SEPP level was positively correlated with FIN, FPG, body mass index (BMI), triglycerides (TG) and HOMA-IR (r = 0.401, 0.202, 0.420, 0.239, 0.445, P < 0.05) and negatively with ISI (r = -0.414, P < 0.01). Multivariate regression analysis demonstrated that SEPP level was independently correlated with insulin resistance (β = 0.293, P < 0.01). And the independent factors for ISI were systolic pressure, HbA1c and SEPP level (β = -0.195, -0.185 and -0.246, P < 0.05).

Serum SEPP level may be an independent risk factor for insulin resistance regardless of age, blood pressure or lipid profile.