The magnitudes of the obesity-induced upregulation of the TLR1, TLR4, TLR5, TLR8, TLR9, and TLR12 genes in the visceral adipose tissue were even greater in the diet-induced obesity (DIO) mice than in the ob/ob mice [7]. Here, TLR4 is linked to obesity due to melanocortin 4 receptor deficiency.