PTPN1 and obesity due to melanocortin 4 receptor deficiency: Protein tyrosine phosphatase-1B (PTP-1B) and α-glucosidase are the most efficient inhibitors of carbohydrate-hydrolyzing enzymes, serving as a most common therapeutic target for type 2 diabetes mellitus (T2DM), as well as being beneficial in the management of blood glucose in patients with T2DM, insulin resistance, and obesity [22, 23].