Small Interfering RNA Mediated Knockdown of Irisin Suppresses Food Intake and Modulates Appetite Regulatory Peptides in Zebrafish.

Small Interfering RNA Mediated Knockdown of Irisin Suppresses Food Intake and Modulates Appetite Regulatory Peptides in Zebrafish. Gen Comp Endocrinol. 2017 Jun 27;: Authors: Sundarrajan L, Unniappan S Abstract Irisin is a myokine encoded in fibronectin type III domain containing 5 (FNDC5). FNDC5 forms an integral part of the muscle post-exercise, and causes an increase in energy expenditure in mammals. Irisin is abundantly expressed in cardiac and skeletal muscles and is secreted upon activation of peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1 alpha). Irisin regulates feeding behaviour and cardiovascular function in mammals. More recently, irisin has gained importance as a potential biomarker for myocardial infarction due to its abundance in cardiac muscle. The goal of this research was to determine whether irisin influences feeding, and regulates appetite regulatory peptides in zebrafish. Intraperitoneal injection of irisin [0.1, 1, 10 and 100 ng/g body weight (BW)] did not affect feeding, but its knockdown using siRNA (10 ng/g BW) caused a significant reduction in food intake. Knockdown of irisin reduced ghrelin and orexin-A mRNA expression, and increased cocaine and amphetamine regulated transcript mRNA expression in zebrafish brain and gut. siRNA mediated knockdown of irisin also downregulated brain derived neurotrophic factor mRNA in zebrafish. This role of endogenous irisin on food intake is likely medi...
Source: General and Comparative Endocrinology - Category: Endocrinology Authors: Tags: Gen Comp Endocrinol Source Type: research