NLRP3 and obesity due to melanocortin 4 receptor deficiency: Several mechanisms have been recognized in the development of obesity-induced chronic inflammation including oxidative stress (148, 149), endoplasmic reticulum stress (150, 151), increasing oxygen consumption leading to adipocyte hypoxia (152, 153), inflammasome activation particularly NLRP3 (154, 155), and pattern recognition receptors (PRR) activation and regulation particularly TLR2 and TLR4 activation (156–158).