BIO

Hi my name is Eva Rucinski and I am from Beverly Hills, Florida. I hope to go on to medical school someday and study psychiatry. My research interests are centered around GLP-1 and how that affects the intake of food in Gcg-Knockdown rats. When I am not studying, I love to run, play soccer, or stay home and play with my cats!

Gcg-Knockdown Rats Overconsume a Palatable Western Diet

Abstract

The peptide product of the gene encoding glucagon (Gcg) is processed to form Glucagon-like peptide-1 (GLP-1) in the intestine and in hindbrain neurons. GLP-1 acts in the brain to reduce intake of palatable, rewarding foods. We developed a homozygous Gcg-Cre knock-in Sprague-Dawley rat model, and discovered that these rats have markedly reduced expression of Gcg and very low levels of GLP-1 (Zheng et al., 2022). The purpose of this experiment was to determine if homozygous Gcg-Cre rats (here, called Gcg-KD rats) display altered food intake compared to wild type (WT) control rats. We hypothesized that Gcg-KD rats will eat more of a palatable “Western Diet” (WD; high in fat and sugar) than WT rats, since Gcg- KD rats have reduced levels of GLP-1 in the body and brain. Home- cage intake of regular chow and WD was assessed every day for 8 weeks, and rats were weighed three times a week. EchoMRI scans were performed before and after the experiment to measure body composition (lean and fat mass). Gcg-KD rats consumed more WD compared to wild type controls, and displayed greater preference for WD vs. chow. This effect was larger in female vs. male rats. Gcg-KD rats also gained more weight and had higher fat mass at the end of the study compared to WT controls. Thus, lower levels of GLP-1 in Gcg-KD rats may lead them to overconsume palatable WD.

Keywords: Gcg, Western Diet, GLP-1