IGF1 and obesity due to melanocortin 4 receptor deficiency: As a consequence, we have an androgenic hypersecretion and the establishment of a self-fed vicious circle, to which insulin and IGF contribute, the latter locally produced in excess and enhanced by the often-coexisting condition of obesity, exerting a synergistic effect with LH in stimulating the synthesis of androgens with an increase in their circulation [27,28,29,30,31].