Comparison of plasma and salivary meteorin-like protein levels in patients with newly diagnosed Type-2 diabetes and treated with metformin.

Abstract

The present study compares the plasma and salivary Metrnl levels of patients newly diagnosed with type-2 diabetes who were treated with metformin for three months with those of a healthy volunteer group and immunohistochemically analyzes Metrnl in salivary glands. 30 healthy volunteers and 30 newly diagnosed type-2 diabetes patients were included in the study. The newly diagnosed diabetes patients were treated with metformin for three months, and the plasma and salivary metformin levels of both groups were measured at baseline and after the three months of metformin treatment in the patient group. Plasma HbA1c, low-density lipoprotein (LDL-C) and Triglyceride (TG) values of all groups were also measured at baseline following three months of metformin treatment. Biopsies were taken from the parotid and submandibular glands and immunohistochemical staining was performed to show Metrnl immunoreactivity. Plasma Metrnl, HbA1c, LDL-C and TG levels were higher in the newly diagnosed diabetes group than in the other group, and salivary Metrnl levels were higher than in the control group after three months of metrformin treatment. An examination of the immunohistochemical staining of salivary gland biopsies under light microscope revealed Metrnl immunoreactivity in the intralobular and interlobular ducts of the parotid gland, while Metrnl immunoreactivity was observed in the acinar cells in the intralobular striated duct and interlobular ducts in the submandibular gland. Plasma Metrnl, HbA1c, LDL-C and TG levels were higher in the newly diagnosed diabetes group than in the other group. Metrnl immunoreactivity was detected in the parotid and submandibular glands. The relationship between Metrnl and DM should be investigated in larger groups.