New available biomarkers to face a worldwide emergency: The childhood obesity

Abstract

Childhood obesity is characterized by a chronic low-grade inflammation process detected through a panel of in- flammatory markers. Adipokines secreted from adipose tissue are key regulators of inflammation in obesity. Increased Tumor Necrosis Factor (TNF)- and Interleukin (IL)-6 levels as well as decreased adiponectin and IL-10 levels are associated with inflammation, tissue injury and complications of obesity. The recent discovery of High Mobility Group Box 1 (HMGB1) protein as a critical mediator of inflammation stimulated an increasing interest in inflammation research field. Obese children are characterized by high levels of this protein, closely related with other inflammatory cytokines, such as IL-6, TNF-, IL-18, resistin and adiponectin. Moreover, prolactin represents another risk marker for obese children and a predictive factor for pro- gression to metabolic syndrome. Leptin and ghrelin are two hormones playing key roles on energy balance. Leptin is responsible from long term regulation of metabolism and ghrelin functions as an appetite stimulatory signal. In contrast to ghrelin, obestatin acts as an anorexigenic hormone by suppressing food intake. Moreover, we also reviewed other gut-derived hormones involved in the regulation of food intake and energy homeostasis, such as amylin, peptide YY and glucagon-like peptide 1. All these peptides could represent important tools to detect eating disorders in children. The aim of this review is to better define the role of new peptides in childhood obesity. The diagnostic and prognostic role of these biomarkers was also assessed, highlighting potential strategies and proteomic medicine that could become possible in the near future.