INS and obesity due to melanocortin 4 receptor deficiency: Subcutaneous adipose tissue from men with obesity and insulin resistant murine 3T3-L1 adipocytes have increased T concentration with reduced lipolytic T release after adrenergic stimulation and are partially “resistant” to testosterone -mediated lipolysis and inhibition of adipogenesis, suggesting a bidirectional relationship between obesity and obesity associated decreases in serum testosterone concentrations [56].