CCR2 and obesity due to melanocortin 4 receptor deficiency: While some studies suggest that Caspase-1 deficiency enhances insulin sensitivity and reduces adipose tissue mass compared to wild-type mice [27], contradictory reports propose that Caspase-1-deficient mice are more susceptible to high-fat diet (HFD)-induced obesity and increased inflammation through the CCL2/C-C chemokine receptor 2 (CCR2) axis in adipose tissue [25].