GRN and obesity due to melanocortin 4 receptor deficiency: Some studies found that the expressions of autophagy indicators were elevated in adipose tissue of humans and mice in obesity [20–22], and the induction of autophagy might benefit in ER stress-induced unfolded protein response, thus we speculated that increased autophagy in adipocytes treated with progranulin could be a decompensatory response to activated ER stress.