Evaluation of the content of lamp-2a in the hypothalamus of animals with high-fat diet induced obesity

• Grant number: 13/25489-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2014
• End date: January 31, 2015
• Field of knowledge: Health Sciences - Nutrition
• Principal Investigator: Marciane Milanski Ferreira
• Grantee: Daisuke Hayashi Neto
• Host Institution: Faculdade de Ciências Aplicadas (FCA). Universidade Estadual de Campinas (UNICAMP). Limeira , SP, Brazil

Abstract

In the last years, it has been occurring on a global scale a startling increase in the number of individuals with obesity, a pathology characterized by the abnormal accumulation of fat that can lead to health risks. The pathogenesis of obesity consists, predominantly, in the loss of the energetic homeostasis that has as a determining factor the dysfunction of the hypothalamus, a region of the brain responsible for the control of the eating behavior and the regulation of the energy expenditure through peripheral hormones signaling. That can occur in order of inflammatory processes due to the consumption of high-fat diets rich in saturated fatty acids, which can lead to deleterious effects over the cellular homeostasis, inducing, for example, endoplasmatic reticulum stress. It has been shown that alterations in the process of autophagy, an important mechanism for the removal of dysfunctional cytosolic proteins and organelles, can lead to the collapse of the hypothalamic homeostasis, causing changes in the body weight. Autophagy is divided, basically, into macroautophagy, microautophagy, and chaperone-mediated autophagy, given that the third one, which is responsible for the degradation of many long-life cytosolic proteins, was shown diminished in the liver of animals fed with a high-fat diet. Considering that the failure or decrement in the process of chaperone-mediated autophagy can lead to the accumulation of dysfunctional proteins and the formation of protein aggregates, which added to the endoplasmatic reticulum stress, can provoke severe impacts to the hypothalamic cells. Therefore, the purpose of this work is to determine the content of the protein LAMP-2A, an indirect marker of the chaperone-mediated autophagy, in the hypothalamus of animals with high-fat diet-induced obesity. (AU)