New trends in the pharmacological intervention of PPARs in obesity: role of natural and synthetic compounds

Obesity is a major health concern for a growing fraction of the population, with the prevalence of obesity and its related metabolic disorders not being fully understood. Over the last decade, many attempts have been undertaken to understand the mechanisms at the basis of this condition, in which the accumulation of fat occurring in adipose tissue, leads to the pathogenesis of obesity related disorders. Among the most recent studies, those on Peroxisome Proliferator Activated Receptors (PPARs) revealed that these nuclear receptor proteins acting as transcription factors, among others, regulate the expression of genes involved in energy, lipid, and glucose metabolisms, and chronic inflammation. The three different isotypes of PPARs, with different tissue expression and ligand binding specificity, exert similar or overlapping functions directly or indirectly linked to obesity. In this study, we reviewed the available scientific reports concerning the PPARs structure and functions, especially in obesity, considering both natural and synthetic ligands and their role in the therapy of obesity and obesity-associated disorders. In the whole, the collected data show that there are both natural and synthetic compounds that show beneficial promising activity as PPAR agonists in chronic diseases related to obesity.