Epigenetic status of subtelomere of peripheral leukocytes corresponds to cardiographic parameters with a sex association.

AIM: The telomere length of somatic cells is associated with systemic aging. The attrition of somatic telomere length is accelerated in pathological conditions, such as cardiovascular diseases. However, clinical parameters of cardiac function have not been well studied in this regard. The present study examined how cardiac function was affected by telomere length and the subtelomeric methylation of peripheral leukocytes.

METHODS: Telomere length was assessed by Southern blotting analysis of genomic DNA extracted from peripheral leukocytes. Subtelomeric methylation was assessed by comparison between the Southern blotting results with a restriction enzyme Msp I and those with Hpa II, a methylation-sensitive isoschizomer of Msp I.

RESULTS: The following parameters were associated with telomere length and/or the subtelomeric methylation status in a sex-associated manner: PR interval, the voltage of QRS complex, QRS interval, QT interval and T wave voltage in electrocardiogram; and ejection fraction, the diameter of the left ventricle at the end diastolic phase, aortic root diameter and inferior vena cava diameter in echocardiogram.

CONCLUSIONS: Cardiac function correlates not only with telomere length, but also with the distribution of the telomere length and subtelomeric DNA methylation status. These imply that the loss of young cells, the accumulation of old cells and the acceleration of such changes in the cell population relate to phenotypes of cardiac aging with relative sex specificity. Furthermore, the PR interval showed a very close association with telomeric parameters in both sexes. Hence, PR is the most reliable candidate as an indicator of biological aging in both sexes. Geriatr Gerontol Int 2018; 18: 1415-1419.