Internal medicine

Telomere

Oxidative stress

Biology

Cardiology

Genetics

Medicine

Journal of Evolution of Medical and Dental Sciences

BACKGROUNDHypertension is one of the leading causes of cardiovascular disease death.Hypertension is associated with oxidative stress.Oxidative stress causes telomere dysfunction.In this study, I have compared telomere dysfunction and oxidative stress among hypertensive patients and age sex matched healthy controls.Aims and Objectives-Oxidative stress is the unifying pathophysiological mechanism responsible for ageing and age-related diseases like diabetes, hypertension, atherosclerosis etc. Oxidative stress is defined as increase in the intracellular concentration of reactive oxygen species.Telomeres are specialised DNA-protein structures located at the ends of eukaryotic chromosomes, whose length is progressively reduced in most somatic cells during ageing.Insulin resistance and oxidative stress are associated with accelerated telomere attrition, implicated in the biology of ageing/ in ageing-related disorders including hypertension.We hypothesised higher oxidative stress, measured by Malondialdehyde (MDA) and Glutathione-S transferase (GST) associated with telomere dysfunction in hypertensive patients.So, a case control study was undertaken to study the dysfunction of telomere in these patients. MATERIALS AND METHODSThe study was conducted at a tertiary care hospital in Delhi, India, which includes 40 hypertensive male patients (aged 45 -65 years) and equal number of age-matched healthy controls.Based on convenience, we have taken 40 patients in each group.We performed biophysical parameters check, routine and special investigations like measurement of MDA levels (Ohkawa method), GST levels (Mozer method).In all subjects, telomere length was measured by real time PCR from the DNA isolated from leucocytes (Cawthon's method) and telomerase activity was measured by measuring hTERT mRNA expression by RT-PCR, Taqman methodology from leucocytes. RESULTSIt was observed that the mean MDA level in cases and controls were 0.90 ± 0.30 and 0.65 ± 0.18 respectively (p= 0.01).The mean GST level in cases and controls were found to be 0.68 ± 0.17 and 1.02 ± 0.32 µmol/mL/min respectively (p= 0.001).We also found that mean telomere length was found to be shorter in hypertensive patients (8.17 ± 1.26 kb) as compared to controls (10.47 ± 1.79 kb) respectively (p < 0.001).The expression of hTERT (mean ∆ct ratio) of cases (-0.18) was higher as compared to control (16.17). CONCLUSIONIt was observed that there was a significant shortening of telomere length with higher oxidative stress in hypertensive patients as compared to healthy control.

COMPARISON OF OXIDATIVE STRESS AND TELOMERE DYSFUNCTION IN HYPERTENSION PATIENTS