Effects of Recombinant Irisin on Body Mass Index, Serum Insulin, Luteinizing Hormone and Testosterone Levels in Obese Female BALB/c Mice

OBJECTIVE: To determine the effects of recombinant irisin on body mass index (BMI), serum insulin, luteinizing hormone (LH) and testosterone levels, and to correlate the serum insulin levels with serum luteinizing hormone and testosterone levels and to correlate the body mass index with serum insulin levels in obese female BALB/c mice. STUDY DESIGN: Laboratory-based experimental study. PLACE AND DURATION OF STUDY: Department of Physiology, Shifa College of Medicine, Islamabad in collaboration with Research Laboratory of Shifa College of Medicine, National Institute of Health (NIH) and Reproductive Physiology Laboratory, Quaid-e-Azam University, Islamabad, from March 2015 to September 2016. METHODOLOGY: Ninety female BALB/c mice were divided into three equal groups. Group A which was the control group was fed with normal chow diet. Group B and Group C were fed with high fat-high sucrose (HF-HS) diet for five weeks to induce obesity. After four weeks group C was divided into two subgroups. Group C-low dose (LD) was injected with low dose irisin and group C-High dose (HD) was injected with high dose irisin for one week. After five weeks, the BMI, serum insulin, LH and testosterone levels were measured in all the groups. Data was analysed by SPSS version 21. P-value of <0.05 was considered significant. RESULTS: Group B showed statistically significant elevation in BMI, serum insulin, LH and testosterone levels as compared to Group A (p <0.001, <0.001, 0.007 and 0.014, respectively). Group C-HD showed statistically significant decrease in BMI, serum insulin, and LH as compared to Group B (p <0.001, 0.013 and 0.028, respectively). Serum testosterone level was also decreased in group C-HD as compared to Group B, however the difference was not significant. CONCLUSION: Obesity increases the serum insulin, LH and testosterone and irisin significantly lowers the elevated BMI, serum insulin and LH levels in female BALB/c mice. It also lowers the elevated testosterone levels, but not significantly.