Comparison of Levels of Telomerase, Oxidative Stress, Adiponectin, Leptin, and Interleukin-6 in First Degree Relatives of Diabetics, Prediabetics, and Diabetics: A Cross-sectional Study

Abstract

Introduction: Rapid beta-cell senescence caused by telomere shortening is associated with type 2 diabetes. Hence, studying telomere dynamics in prediabetic stages or First Degree Relatives of Diabetics (FDRD) is crucial. Telomere attrition is influenced by oxidative stress, which is prevalent in diabetics, prediabetics, and FDRD due to dyslipidaemia. The relationship between telomerase activity and glycaemic control, insulin resistance, oxidative stress, dyslipidaemia, adipocytokines, and inflammatory markers remains unclear and requires further investigation. Aim: To assess and compare telomerase levels, oxidative stress (malondialdehyde), adipocytokines (leptin, adiponectin, and Interleukin-6 (IL-6), lipid profiles, and Body Fat Percentage (BF%) across the glycaemic spectrum in the Indian population. Materials and Methods: This cross-sectional study was conducted at the Department of Physiology, JIPMER, Puducherry, from 2016 to 2018, involving four groups: Group I (control group, non diabetic, healthy, non FDRD, n=63), Group II (FDRD, non diabetic, n=63), Group III (prediabetics, n=63), and Group IV (diabetics, n=63). Participants aged 30-50 years, matched for age and gender, were recruited. Anthropometric variables, cardiovascular parameters, telomerase levels, Malondialdehyde (MDA), adiponectin, leptin, IL-6, and lipid profiles were assessed. Mean differences were analysed using one-way Analysis of Variance (ANOVA) or Kruskal-Wallis test, while Pearson’s correlation analysis was performed to assess the correlation between telomerase levels, glucose concentration, and BF%. Results: An increasing trend in circulating telomerase levels, lipid profiles, and BF% was observed across the glycaemic spectrum. Circulating leptin concentrations did not differ between the groups. However, there was a decrease in circulating adiponectin concentration as the glycaemic status progressed. Increased MDA levels were observed only in the diabetics group. Telomerase levels showed a significant association with circulating glucose concentration (fasting and postprandial) and BF%. Conclusion: The circulating telomerase level increased along the glycaemic spectrum (non FDRD<FDRD<Prediabetics< Diabetics). The major finding was that telomerase level increases even in normoglycaemic FDRD. Oxidative and inflammatory parameters did not significantly differ in FDRD compared to non FDRD individuals. Notably, adiponectin, Tumour Necrosis Factor (TNF)-α, Low-Density Lipoprotein (LDL), and HighDensity Lipoprotein (HDL) were the parameters that showed changes in FDRD.

Keywords

• adipocytokines
• diabetes mellitus
• prediabetic state
• type 2 diabetes