Elevated circulating vaspin levels were decreased by rosiglitazone therapy in T2DM patients with poor glycemic control on metformin alone.

Vaspin has been regarded as a novel adipokine with potential insulin sensitizing properties. The aim of the present study is to investigate the effects of rosiglitazone therapy on plasma vaspin in type 2 diabetes patients (T2DM) inadequately controlled on metformin alone. A total of 105 subjects, including 37 subjects with normal glucose tolerance (NGT), 37 subjects with impaired glucose regulating (IGR), and 31 T2DM patients with poor glycemic control on metformin alone were enrolled in this study. Fasting plasma vaspin levels were higher in T2DM patients with poor glycemic control than that in IGR and NGT groups (1.19±0.74 vs. 0.46±0.26 and 0.54±0.28 μg/L, P<0.05). There was no difference between IGR and NGT groups. In T2DM patients, fasting plasma vaspin concentrations were significantly decreased after rosiglizatone therapy for 12 weeks (1.19±0.74 vs. 0.91±0.54 μg/L, P<0.05), accompanied with significant amelioration of insulin sensitivity and glucose control. Plasma vaspin levels were positively associated with the fasting insulin and the homeostasis model assessment of IR (HOMA-IR). In conclusion, plasma vaspin level is higher in T2DM patients with poor glycemic control. And rosiglitazone therapy decreased plasma vaspin levels through glucose and insulin sensitivity regulation.