Recombinant Irisin Ameliorates Insulin Resistance in Type 2 Diabetic Mice

Introduction: An exercise-induced myokine, Irisin, is shown to cause the browning of white adipose tissue, promote glycogen storage, and inhibit glucose and cholesterol formation in the liver. Studies have, however, shown a reduction of circulating irisin in type 2 diabetes, suggesting altered secretion of myokines in the setting of insulin resistance. Aims & Objectives: This study explored the effect of recombinant irisin on insulin resistance and oxidative strain in laboratory induced type 2 diabetic mice. Place and Duration of Study: Animal House and Laboratory of Akhter Saeed Medical and Dental College, Lahore from March 2018 to December 2018. Material & Methods: A randomized comparative trial was conducted. Type 2 diabetes mellitus was produced in 60 male albino mice by feeding them a fat rich diet (60% kcal fat) for 6 weeks, followed by low dose streptozotocin (40 mg/kg body weight). Thirty diabetic mice acted as diabetic controls and thirty mice were administered recombinant irisin intra-peritoneally, 1mg/kg body weight daily for 4 weeks. Serum fasting glucose, insulin, lipid profile, and malondialdehyde were estimated thereafter. Insulin resistance was predicted by employing the HOMA-IR score and triglyceride-HDL ratio. The data was analyzed by using SPSS (version 21), a p value less than 0.05 was regarded statistically significant Results: Diabetic mice that received recombinant irisin showed significant (p=0.000) reduction in fasting blood glucose (249.03±66.17mg/dl) and serum insulin (4.61±0.08µU/L) as compared to the diabetic control mice (428.50±78.13 mg/dl, 5.95±0.72µU/L). The degree of insulin sensitivity as determined by HOMA-IR score and triglyceride HDL ratio was significantly increased in the diabetic irisin groups as compared to the diabetic control group. This correlated with reduction in the oxidative stress marker malondialdehyde. Conclusion: Recombinant Irisin improved insulin sensitivity and reduced oxidative strain in type 2 diabetic mice.