C-peptide as an investigatory tool for endogenous insulin secretion in Type 2 diabetes mellitus patients of Mahakaushal region

Abstract

Background: Type 2 diabetes mellitus (T2DM) is a disease state of chronic hyperglycemia that occurs due to decrease insulin secretion or attenuated insulin response or both. Insulin resistance with relative insulin deficiency is a peculiar feature of T2DM. Proinsulin is synthesized by the beta cell of the pancreas. Before secretion into the portal vein, proinsulin cleaves into equal quantities of insulin and C-peptide. The secreted insulin gets extensively metabolized by the liver and has a shorter half-life than C-peptide. Thus, C-peptide levels more accurately perceive the endogenous insulin secretion of the pancreas. Hence, C-peptide can be used to interpret the significant pathophysiology behind T2DM. Aims and Objectives: The aim of the study was to perceive endogenous insulin secretion or beta cell functioning of the pancreas by measuring C-peptide levels in T2DM patients. Materials and Methods: The cross-sectional study were conducted on 120 random T2DM patients attending the outpatient clinic of tertiary care hospital (Netaji Subash Chandra Bose Medical College, Jabalpur) from January 2021 to August 2022. All T2DM patients were evaluated with fasting C-peptide levels. Results: Among 120 cases,25 (20.8%) have low C-peptide levels of <1.1 ng/dL, indicating poor insulin reserve.33 (27.5%) have normal C-peptide levels, and approximately half −62 (51.6%) have high C-peptide levels of more than 3.3 ng/dL, indicating adequate endogenous insulin secretion and insulin resistance is the significant pathophysiology behind T2DM. Conclusion: C-peptide level is a useful investigation to perceive endogenous insulin secretion and beta cell function of the pancreas. Insulin resistance rather than insulin deficiency is the significant pathophysiology behind T2DM.