Degree
Master of Science
Program
Physiology and Pharmacology
Supervisor
Dr. Morris Karmazyn
Abstract
Leptin and adiponectin are the adipokines that are shown to exert pro-hypertrophic and anti-hypertrophic effects respectively, in cardiomyocytes. We sought to determine the direct interaction between the adipocytes and cardiomyocytes during endothelin-1 (ET-1)-induced cardiomyocyte hypertrophy and determine the role of leptin and adiponectin.
The adipose tissue conditioned medium (ACM) inhibited the ET-1-induced hypertrophy in a concentration-dependent manner and this anti-hypertrophic effect was more potent or reversed in the presence of leptin receptor antagonist (LRA; 0.1 nM) or adiponectin receptor-1 antibody (ARA; 100 ng/mL), respectively. ACM from heart failure rats induced by coronary artery ligation or obese rats did not mitigate the ET-1 induced hypertrophy in cardiomyocytes.
These studies demonstrate that the net anti-hypertrophic activity of ACM in ET-1-induced cardiac hypertrophy is likely mediated by adiponectin due activation of AMPK and determined by the leptin to adiponectin ratio. Heart failure and obese-induced pathology changes the characteristics of adipocytes although the underlying mechanisms for this effect are not completely known.
Recommended Citation
Bairwa, Suresh Chandra, "Modulation of the Cardiomyocyte Hypertrophic Responses to Endothelin-1 by Adipocytes" (2014). Electronic Thesis and Dissertation Repository. 2592.
https://ir.lib.uwo.ca/etd/2592