Past Issue

Volume 20, Number 3, Autumn 2018, Serial Number: 79, Pages: 427-434

Effect of L-Carnitine Supplementation on Apelin and Apelin Receptor (Apj) Expression in Cardiac Muscle of Obese Diabetic Rats


Neda Ranjbar Kohan, Ph.D, 1, Saeed Nazifi, Ph.D, 1, Mohammad Reza Tabandeh, Ph.D, 2, 3, *, Maryam Ansari Lari, Ph.D, 4,
Department of Clinical Studies, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
Stem Cells and Transgenic Technology Research Center, Shahid Chamran University of Ahvaz, Ahvaz, Iran
Department of Food Hygiene, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
*Corresponding Address: P.O.Box: 61355-145 Department of Biochemistry and Molecular Biology Faculty of Veterinary Medicine Shahid Chamran University of Ahvaz Ahvaz Iran Email:m.tabandeh@scu.ac.ir

Abstract

Objective

L-carnitine (LC) has been shown to protect cardiac metabolism in diabetes patients with cardiovascular diseases (CVDs). Apelin, a newly discovered adipocytokines, is an important regulator of cardiac muscle function; however, the role of the level of expression of Apelin axis in improvement of cardiac function by LC in diabetic patients, is not clear. In the present study, obese insulin-resistant rats were used to determine the effect of LC, when given orally with a high-calorie diet, on Apelin and Apelin receptor (Apj) expression in cardiac muscle.

Materials and Methods

In this experimental study, rats were fed with high-fat/high-carbohydrate diet for five weeks and subsequently were injected with streptozotocin 30 mg/kg for induction of obesity and insulin resistance. After confirming the induction of diabetes (serum glucose above 7.5 mmol/L), the animals received LC 300 mg/kg in drinking water for 28 days. On days 0, 14 and 28 after treatment, cardiac Apelin and Apj gene expression was evaluated by real time polymerase chain reaction (PCR) analysis. Serum levels of insulin, Apelin, glucose, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and the homeostasis model assessment of insulin resistance (HOMA-IR) were also measured using commercial kits.

Results

Cardiac Apelin and Apj expression and serum Apelin were increased in obese rats, while LC supplementation decreased the serum levels of Apelin and down-regulated Apelin and Apj expression in cardiac muscle. These changes were associated with reduced insulin resistance markers and serum inflammatory factors and improved lipid profile.

Conclusion

We concluded that LC supplementation could attenuate the over-expression of Apelin axis in heart of diabetic rats, a novel mechanism by which LC improves cardiovascular complications in diabetic patients.