NLRP3 and obesity due to melanocortin 4 receptor deficiency: Moreover, the biochemical analysis showed that obesity increased the caspase-1 activity and IL-1β production in Asm+/+ mice but not in Asm−/− mice, suggesting the essential role of Asm gene in mediating the obesity-induced NLRP3 inflammasome formation and activation in glomeruli of mice.