Consistently, in vivo studies have demonstrated that mice lacking AMPKβ1 in haematopoietic cells exhibit the loss of AMPK activity in macrophages, accompanied by the increased accumulation of M1 macrophages in the liver and accelerated development of insulin resistance in response to diets that promote obesity [70, 112]. Here, PRKAB1 is linked to obesity due to melanocortin 4 receptor deficiency.