DPP4 and Other metabolic disease: The investigated parameters related to metabolic disorders included sirtuin 1 (SIRT-1), sirtuin 3 (SIRT-3), sirtuin 6 (SIRT-6), irisin (IRS), myostatin (MSTN), peptide YY (PYY), glucagon-like peptide 1 (GLP-1), and dipeptidyl peptidase 4 (DPP-4).