Associations of miR-146a polymorphism with diabetic peripheral neuropathy and clinical effect

  Objective  To investigate the relationships between the miR-146a polymorphism and diabetic peripheral neuropathy (DPN), clinical efficacy of patients with type 2 diabetes mellitus (T2DM).

  Methods  A total of 524 patients with T2DM were enrolled, including 299 patients with simple diabetes mellitus (simple T2DM group) and 225 T2DM patients with DPN (DPN group). Blood DNA was extracted from all patients and polymorphisms in the miR-146a gene were analyzed using TaqMan probe. All patients with DPN were treated with epinostat and mecobalamin, and the associations between miR-146a gene polymorphisms and DPN of susceptibility, clinical efficacy were compared.

  Results  The duration of diabetes in the DPN group was longer than that in the simple T2DM group, fasting blood glucose(FPG), hemoglobin A1c (HbA1c), fasting insulin(FINS) and insulin resistance index(HOMA-IR) in the DPN group were significantly higher than those in the simple T2DM group (P < 0.05). The distribution frequency of GG genotype in the DPN group was higher than that in the simple T2DM group (P < 0.05), but the distribution frequency of CG genotype was lower than that in the simple T2DM group (P < 0.05). Binary Logistic regression analysis showed that the duration of diabetes mellitus, FPG, HbA1C, HOMA-IR and miR-146a genotypes were independent risk factors for DPN in T2DM patients (P < 0.05). The susceptibility of DPN in patients with GG genotype was significantly higher than that in patients with CC genotype (P < 0.05). After 3 months of treatment, the motor and sensory nerve conduction velocities of the peroneal, ulnar, tibial and median nerves were significantly increased (P < 0.05), and the Toronto Clinical Scoring System (TCSS) scores were significantly decreased (P < 0.05). After 3 months of treatment, motor sensory nerve conduction velocity in patients with GG genotype was significantly lower than that of CC or CG genotype patients (P < 0.05), TCSS score was significantly higher than that in patients with CC or CG genotype (P < 0.05).

  Conclusion  The gene polymorphism of miR-146a is associated with susceptibility and clinical outcome of DNP. In T2DM patients with GG genotype, the risk of DNP is higher and the clinical outcome is worse.