Telomere length attrition, a marker of biological senescence, is inversely correlated with triglycerides and cholesterol in South Asian males with type 2 diabetes mellitus

Abstract

South Asians have a higher risk of type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) than white Caucasians, for a given BMI. Premature biological ageing, assessed by reduction in telomere length (TL), may be mediated by factors resulting from altered metabolic profiles associated with obesity. We hypothesise that ethnicity and metabolic status represent detrimental factors contributing to premature biological ageing. Therefore we assessed TL in two South Asian, age and BMI-matched cohorts [T2DM (n = 142) versus non-T2DM (n = 76)] to determine the effects of BMI, gender, lipid and CVD profile on biological ageing. Genomic DNA was obtained from the UKADS cohort; biochemical and anthropometric data was collected and TL was measured by quantitative real-time PCR. Our findings indicated a gender-specific effect with reduced TL in T2DM men compared with non-T2DM men (P = 0.006). Additionally, in T2DM men, TL was inversely correlated with triglycerides and total cholesterol (r = -0.419, P < 0.01; r = -0.443, P < 0.01). In summary, TL was reduced amongst South Asian T2DM men and correlated with triglycerides and total cholesterol. This study highlights enhanced biological ageing among South Asian, T2DM men, which appears to be tracked by changes in lipids and BMI, suggesting that raised lipids and BMI may directly contribute to premature ageing.

Figure 1

(a) Gender distribution of telomere length (TL) in peripheral blood mononuclear cells in South Asian non-T2DM (male: dark circles, females: open circles) and T2DM (male: dark squares, females: open squares); (b) TL in peripheral blood mononuclear cells in South Asian non-T2DM (circles) and T2DM (squares). TL is represented as mean (dotted line) ± SD, *P < 0.05 and **P < 0.01.

Figure 2

The relationship between total cholesterol and TL in South Asian T2DM group. (a) Linear regression analysis of total cholesterol and TL in T2DM (clear triangles); (b) linear regression analysis of total cholesterol and TL in T2DM by gender (male: dark squares and solid line, females: open squares and dotted line).

Figure 3

The relationship between triglycerides and TL in South Asian T2DM group. (a) Linear regression analysis of triglycerides and TL in T2DM (clear triangles); (b) linear regression analysis of triglycerides and TL in T2DM by gender (male: dark squares and solid line, females: open squares and dotted line).

Figure 4

TL in obese male T2DM subjects (BMI: 25–34.9 kg/m²) is inversely correlated with triglycerides (N = 39).