UCP1 and obesity due to melanocortin 4 receptor deficiency: Another study indicated that, loss of NOD1 accelerated obesity in mice fed a HFD, accompanied by increased levels of free thyroidal T4, reduced expression of uncoupling protein 1 (UCP1) in brown adipose tissues, and enhanced infiltration of inflammatory cells in white adipose tissues and liver tissues, suggesting a protective role of NOD1 against inflammation and obesity [68].