PRKAA1 and obesity due to melanocortin 4 receptor deficiency: Notably, inducing the development of brown fat at the expense of the white one might be a beneficial approach in the fight against obesity; luteolin was shown to increase energy expenditure in mice, promote thermogenic program in mouse brown adipose tissues and subcutaneous adipose tissues, and induce white-to-brown fat transition in subcutaneous adipose tissues through an AMP-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor gamma co-activator (PCG)1α pathway-mediated mechanism [59].