NADK and obesity due to melanocortin 4 receptor deficiency: As we could observe in this review, chronic and persistent inflammation, as well as the metabolic consequences that this causes, is one of the most widely studied conditions in models of obesity, and the regulation of genes such as NADK and KLF4, which are mediated by miRNAs such as miR-690 and miR-34a, suggests that microRNAs are directly involved in the polarization of macrophages to an anti-inflammatory or proinflammatory phenotype [22,25].