Shortening of the leucocytes’ telomeres length in T2DM independent of age and telomerase activity

Abstract

This study aimed to examine the role of plasma telomerase (TE), plasma insulin, patient's age and disease duration in determination of the leucocytes' telomeres length (LTL) in T2DM. Blood samples from Kuwaiti patients with T2DM (110) and non-diabetic subjects (94) were analyzed by SYBR Green Quantitative PCR for estimation of the Absolute Human Telomere Length and by ELISA for estimation of the TE activity and insulin level. The body mass index (BMI) and HOMA-IR were calculated. The results revealed marked shortening of the LTL in T2DM compared with the non-diabetic subjects (6.068, 2.276-11.652 vs. 10.979, 6.495-23.402kb), p < 0.001, while the TE concentration was comparable between the two groups (3.16, 0.00-6.02 vs. 4.16, 1.38-7.94 U/L, respectively), p 0.100. Importantly, in T2DM the LTL did not vary significantly with the disease duration (1month to 40years), p 0.959, and did not correlate with age, BMI, insulin-resistance, or glycemic parameters. Interestingly, there was a positive correlation between the LTL and insulin levels in T2DM (CC 0.211, p 0.0419). Finally, in non-diabetic subjects, HbA1c ≥ 6% was associated significantly with shorter LTL, this observation together with the lack of association of the LTL with the disease duration, suggests a causal role of short telomeres in T2DM development. This study confirmed the LTL shortening in T2DM in Kuwaiti Arabs, and showed that the LTL was independent of age and TE activity but positively influenced by insulin levels. Furthermore, the study suggested that telomeres shortening could be a risk factor for T2DM.