INS and obesity due to melanocortin 4 receptor deficiency: Autophagy impairment is connected to the PI3K-Akt-mTOR signaling pathway and it is also associated with (i) PCOS, as it regulates the androgens, insulin, and insulin-like growth factors [39]; (ii) mental illnesses, as it links to the protein synthesis in synapses [40]; and (iii) obesity, as it is activated by excessive nutrition [30].