Increased Hypothalamic Anti-Inflammatory Mediators in Non-Diabetic Insulin Receptor Substrate 2-Deficient Mice

Identifier:  imarina:9227050

Handle: https://hdl.handle.net/20.500.11797/imarina9227050

Authors:  Vinaixa, Maria; Canelles, Sandra; Gonzalez-Murillo, Africa; Ferreira, Vitor; Grajales, Diana; Guerra-Cantera, Santiago; Campillo-Calatayud, Ana; Ramirez-Orellana, Manuel; Yanes, Oscar; Frago, Laura M; Valverde, Angela M; Barrios, Vicente

Abstract:
Insulin receptor substrate (IRS) 2 is a key mediator of insulin signaling and IRS-2 knockout (IRS2(-/-)) mice are a preclinical model to study the development of diabetes, as they develop peripheral insulin resistance and beta-cell failure. The differential inflammatory profile and insulin signaling in the hypothalamus of non-diabetic (ND) and diabetic (D) IRS2(-/-) mice might be implicated in the onset of diabetes. Because the lipid profile is related to changes in inflammation and insulin sensitivity, we analyzed whether ND IRS2(-/-) mice presented a different hypothalamic fatty acid metabolism and lipid pattern than D IRS2(-/-) mice and the relationship with inflammation and markers of insulin sensitivity. ND IRS2(-/-) mice showed elevated hypothalamic anti-inflammatory cytokines, while D IRS2(-/-) mice displayed a proinflammatory profile. The increased activity of enzymes related to the pentose-phosphate route and lipid anabolism and elevated polyunsaturated fatty acid levels were found in the hypothalamus of ND IRS2(-/-) mice. Conversely, D IRS2(-/-) mice have no changes in fatty acid composition, but hypothalamic energy balance and markers related to anti-inflammatory and insulin-sensitizing properties were reduced. The data suggest that the concurrence of an anti-inflammatory profile, increased insulin sensitivity and polyunsaturated fatty acids content in the hypothalamus may slow down or delay the onset of diabetes.