INS and obesity due to melanocortin 4 receptor deficiency: 1.CD47 deficiency promotes brown adipocyte differentiation via cGMP/PKG signaling, enhancing energy expenditure and reducing diet-induced obesity.2.CD47-deficient mice exhibit reduced lipid droplet accumulation in brown adipose tissue, increased expression of UCP1 and CPT1b, decreased macrophage infiltration in adipose tissue, attenuated inflammation, reduced hepatic steatosis, and improved glucose tolerance and insulin sensitivity.