| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 336197 | Psychoneuroendocrinology | 2015 | 14 Pages |
•Leukocyte telomere length (LTL) was not associated with depression.•Telomerase activity was higher in men with depression even after adjustment for potential confounders.•Variability in reports of LTL in depression might be due to residual confounding and methodology differences.
SummaryBackgroundLeukocyte telomere length (LTL) is a marker of cellular turnover and oxidative stress. Studies suggest major depressive disorder (MDD) is associated with oxidative stress, but examinations of MDD and LTL have yielded mixed results, likely because of differences in measurement methods and unmeasured confounding. This study examined LTL and telomerase activity in 166 individuals with MDD compared to 166 age- and gender-matched matched controls free of any psychiatric disorder, using well-validated assays and clinical assessment methods, and controlling for a range of potential confounders.MethodsSubjects aged 18 to 70 were evaluated by trained raters and provided blood for LTL and telomerase activity measurement. LTL was assayed using Southern blot and replicated with qPCR, and telomerase activity was assayed with a repeat amplification protocol using a commercial kit.ResultsThere was no significant difference in telomere length for individuals with MDD [mean (SD) = 9.1 (3.0) kbp] compared to controls [mean(SD) = 8.9(2.5) kbp] measured by Southern blot (p = 0.65) or by confirmatory qPCR (p = 0.91) assays. Controlling for potential confounders did not alter the results. Telomerase activity did not differ by MDD diagnosis overall (p = 0.40), but the effect of MDD was significantly modified by gender (t(299) = 2.67, p = 0.0079) even after controlling for potential confounders, with telomerase activity significantly greater only in males with MDD versus controls.ConclusionOur well-characterized, well-powered examination of concurrently assessed telomere length and telomerase activity in individuals with clinically significant, chronic MDD and matched controls failed to provide strong evidence of an association of MDD with shorter LTL, while telomerase activity was lower in men with MDD.
