Tanycytes and Hypothalamic Inflammation Associated with Obesity

Tufts Medical Center, Boston MA

Investigators

Abstract

? DESCRIPTION (provided by applicant): We hypothesize that hypothalamic inflammation associated with high fat feeding arises as a result of Toll-like receptor (TLR) signaling in a specialized cell type lining the inferolateral walls of the third ventricle, the alpha tanycyte. We propose that the activation of NF-?B in these cells releases inflammatory mediators into feeding-related centers in the mediobasal hypothalamus, increasing feeding and/or altering the sensitivity of arcuate/ventromedial nucleus neurons to leptin and/or insulin. To test this hypothesis, RNA-Seq analysis will be used to identify the complete gene expression profile of alpha tanycytes in response to a HFD, with particular emphasis given to the identification of genes and pathways involved in inflammation. Based on this analysis, the effect of a HFD on food intake, energy expenditure, glucose homeostasis, leptin and insulin sensitivity, and other parameters of hypothalamic inflammation will be studied in transgenic animals with conditional KO in alpha tanycytes of selected genes identified in the RNA-Seq analysis. We propose that these studies will demonstrate a critical role of tanycytes in the pathophysiology of hypothalamic inflammation associated with high fat feeding, uncovering new knowledge in understanding the pathogenesis of obesity and a potentially new pharmacologic target for the treatment of obesity.