Acute exercise suppresses hypothalamic PTP1B protein level and improves insulin and leptin signaling in obese rats

• Grant number: 13/22334-8
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: December 01, 2013
• End date: May 31, 2014
• Field of knowledge: Biological Sciences - Physiology - General Physiology
• Principal Investigator: José Rodrigo Pauli
• Grantee: José Rodrigo Pauli
• Host Institution: Faculdade de Ciências Aplicadas (FCA). Universidade Estadual de Campinas (UNICAMP). Limeira , SP, Brazil

Abstract

Hypothalamic inflammation is associated with insulin and leptin resistance, hyperphagia, and obesity. In this scenario, hypothalamic protein tyrosine phosphatase 1B (PTP1B) has emerged as the key phosphatase induced by inflammation that is responsible for the central insulin and leptin resistance. Here, we demonstrated that acute exercise reduced inflammation and PTP1B protein level/activity in the hypothalamus of obese rodents. Exercise disrupted the interaction between PTP1B with proteins involved in the early steps of insulin (IR and IRS-1) and leptin (JAK2) signaling, increased the tyrosine phosphorylation of these molecules, and restored the anorexigenic effects of insulin and leptin in obese rats. Interestingly, the anti-inflammatory action and the reduction of PTP1B activity mediatedby exercise occurred in an interleukin-6 (IL-6)-dependent mannerbecause exercise failed to reduce inflammation and PTP1B protein level after the disruption of hypothalamic-specific IL-6 action in obese rats.Conversely, intracerebroventricular administration of recombinant IL-6 reproduced the effects of exercise, improving hypothalamic insulin andleptin action by reducing the inflammatory signaling and PTP1B activity in obese rats at rest. Taken together, our study reports that physical exercise restores insulin and leptin signaling, at least in part, by reducinghypothalamic PTP1B protein level through the central anti-inflammatory response. (AU)