GCG and diabetes mellitus: Diabetes is the most common endocrine disorder, that is, multifaceted condition that includes β-cell dysfunction, neurotransmitter dysfunction, decreased insulin secretion, decreased incretin effect, increased hepatic glucose production, increased glucagon secretion, decreased glucose uptake, peripheral insulin resistance, and elevated hepatic gluconeogenesis together with hypertension, dyslipidemia, obesity, and cardiovascular disease [2].