Obesity, insulin resistance and comorbidities? Mechanisms of association

• Published in: Arquivos brasileiros de endocrinologia e metabologia Vol. 58; no. 6; pp. 600 - 609
• Main Authors: Castro, Ana Valeria B, Kolka, Cathryn M, Kim, Stella P, Bergman, Richard N
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Endocrinologia e Metabologia 01-08-2014
• Subjects: Adipose Tissue - pathology; Adipose Tissue - physiopathology; Animals; Apoptosis; Body Fat Distribution; ENDOCRINOLOGY & METABOLISM; Endoplasmic Reticulum - metabolism; Humans; Hyperinsulinism - complications; Hyperinsulinism - metabolism; Insulin Resistance; Mitochondria - metabolism; Obesity - complications; Obesity - metabolism; Obesity - physiopathology; Oxidation-Reduction; Oxidative Stress; Risk Assessment; metabolic syndrome; Obesity; fat distribution; síndrome metabólica; ectopic fat; resistência à insulina; gordura visceral; Obesidade; distribuição de gordura; gordura ectópica; visceral fat; insulin resistance
• ISSN: 0004-2730; 1677-9487; 1677-9487; 0004-2730
• DOI: 10.1590/0004-2730000003223

Overall excess of fat, usually defined by the body mass index, is associated with metabolic (e.g. glucose intolerance, type 2 diabetes mellitus (T2DM), dyslipidemia) and non-metabolic disorders (e.g. neoplasias, polycystic ovary syndrome, non-alcoholic fat liver disease, glomerulopathy, bone fragility etc.). However, more than its total amount, the distribution of adipose tissue throughout the body is a better predictor of the risk to the development of those disorders. Fat accumulation in the abdominal area and in non-adipose tissue (ectopic fat), for example, is associated with increased risk to develop metabolic and non-metabolic derangements. On the other hand, observations suggest that individuals who present peripheral adiposity, characterized by large hip and thigh circumferences, have better glucose tolerance, reduced incidence of T2DM and of metabolic syndrome. Insulin resistance (IR) is one of the main culprits in the association between obesity, particularly visceral, and metabolic as well as non-metabolic diseases. In this review we will highlight the current pathophysiological and molecular mechanisms possibly involved in the link between increased VAT, ectopic fat, IR and comorbidities. We will also provide some insights in the identification of these abnormalities.