Overexpression of irisin in the liver of mice, via adenoviral delivery, increases energy expenditure and reduces high fat diet-induced obesity.67 These data indicate that irisin could have the potential to induce WAT browning—the induction of brite cells in WAT—in human subcutaneous adipose tissue. This evidence concerns the gene FNDC5 and obesity due to melanocortin 4 receptor deficiency.