A Study on the Impact of Irisin "A Novel Myokine" in Ameliorating Polyneuropathy of Experimentally-Induced Diabetic Rats

Abstract
Background: Irisin is a new myokine, has been known to its effect on diabetes.
Objectives: This work is designated to evaluate the possible neuroprotective role of irisin in ameliorating DPN in an experimental model of type 2 diabetes mellitus (T2DM) in adult male albino rats.
Patients and Methods: 40 male albino rats of local strain were used, the rats will be randomly divided into 4 equal groups, 10 rats each, control group, irisin group, diabetic group and diabetic-irisin group. Diabetes was induced by feeding rats a high-fat diet (60% kcal fat) for 4 weeks, then they will subjected to a single IP injection of Streptozotocin (STZ) of 40mg/kg in 10ml sodium citrate buffer PH 7.4. rats in irisin group will be injected S.C subcutaneously with irisin 150ul per rat for 4 weeks during which the rats will supple-mented with a normal chow diet. Rats in diabetic-irisin group will be treated with SC injection of irisin 150ul per rat for 4 weeks during which the rats will be supplemented with a normal chow diet. At the end of the experiments (after 4 weeks), rats will be subjected to the following measurements: Food intake, body weight, height and Body Mass Index (BMI), waist circumference, hot plate analgesia meter test, perirenal fat pads/body weight ratio, Nerve Conduction Velocity (NCV) of the sciatic nerves. Blood samples were collected for meas-uring serum glucose and serum insulin and Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), HbA1C, serum Tumor Necrosis Factor alpha (TNF-a), sciatic nerve tissue level of irisin receptors gene expression, Glutathione Peroxidase1 enzyme (GPX1) and Thio Barbituric Acid Reac-tive Substances (TBARS).
Results: T2DM resulted in substantial alterations in biochemical variables and the markers of inflammation (in-crease TNF-a) and oxidative stress (rise of TBARS and decrease of GPX-1) in the sciatic nerve tissue. Irisin supple-mentation effectively restored the abnormalities, suggesting that this compound would be beneficial in mitigating the nereve conduction deterioration associated with T2DM.
Conclusion: Irisin improve nerve conduction velocity in diabetic neuropathy associated with T2DM.