NOD2 and obesity due to melanocortin 4 receptor deficiency: Of the 22 human NLRs known to date [48], six proteins (NLRP3, NLRP6, NOD1, NOD2, NLRC5 and NLRP12) (Figure 1) have been described to be associated with obesity and low-grade inflammation and one (NLRP3) with postprandial inflammation.