Telomere Length In White Blood Cells Research Articles

Shorter telomere length of white blood cells is associated with higher rates of aneuploidy among infertile women undergoing in vitro fertilization

To evaluate whether the telomere length of white blood cells (WBC) and cumulus cells (CC) in an infertile population is associated with ovarian and embryonic performance. Prospective cohort study. Academic-affiliated private practice. A total of 175 infertile women undergoing invitro fertilization (IVF) at a single center between July 2017 and December2018. On the day of oocyte retrieval, genomic DNA was isolated from WBC and CC samples. Telomere length assessment was performed for both tissue types using quantitative real-time polymerase chain reaction. Telomere lengths were normalized using an AluYa5 sequence as an endogenous control, and linear regressions were applied. This study assessed the relationship between relative telomere length of WBC and CC samples and measures of ovarian and embryonic performance. Specifically, patient age, antimüllerian hormone (AMH) level, peak estradiol (E2) level, number of oocytes retrieved, number of mature (MII) oocytes retrieved, blastulation rate, and aneuploidy rate were assessed. There was a statistically significant relationship between WBC relative telomere length and patient age as well as rates of embryonic aneuploidy, with shorter WBC relative telomere length associated with increasing patient age (P<.01) and higher rates of aneuploidy (P=.01). No statistically significant relationships were observed between WBC relative telomere length and the other outcome measures. No significant associations were noted between CC relative telomere length and any outcomes assessed in this study. The relationship between WBC relative telomere length and aneuploidy warrants further investigation, particularly because significant overlap exists between increasing maternal age and rates of embryonic aneuploidy.

Telomere length is associated with oppositional defiant behavior and maternal clinical depression in Latino preschool children.

Exposure to psychological stress and depression are associated with shorter white blood cell telomere length (TL) in adults, possibly via associated lifelong oxidative stressors. Exposure to maternal depression increases risk for future depression and behavior problems in children, and Latino youth are at high risk. Few studies have evaluated the role of exposure to maternal depression or child behavior in relation to TL in children. We assessed early-childhood exposures to maternal depression from birth to the age of 5 years and child behavior from ages 3–5 years in a cohort of Latino children in relation to child leukocyte TL at ages 4 and 5 years. Children who had oppositional defiant behavior at 3, 4 or 5 years had shorter TL than those without by ~450 base pairs (P<0.01). In multivariate analyses, independent predictors for shorter TL at 4 and 5 years of age included oppositional defiant disorder at 3, 4 or 5 years (β=−359.25, 95% CI −633.84 to 84.66; P=0.01), exposure to maternal clinical depression at 3 years of age (β=−363.99, 95% CI −651.24 to 764.74; P=0.01), shorter maternal TL (β=502.92, 95% CI 189.21–816.63) and younger paternal age at the child's birth (β=24.63, 95% CI 1.14–48.12). Thus, exposure to maternal clinical depression (versus depressive symptoms) in early childhood was associated with deleterious consequences on child cellular health as indicated by shorter TL at 4 and 5 years of age. Similarly, children with oppositional defiant behavior also had shorter TL, possibly related to early exposures to maternal clinical depression. Our study is the first to link maternal clinical depression and oppositional defiant behavior with shorter TL in the preschool years in a relatively homogenous population of low-income Latino children.

Childhood Growth, IQ and Education as Predictors of White Blood Cell Telomere Length at Age 49–51 Years: The Newcastle Thousand Families Study

BackgroundTelomere length is emerging as a potential factor in the pathogenesis of cardiovascular disease. We investigated whether birth weight, infant growth, childhood cognition and adult height, as well as a range of lifestyle, socio-economic and educational factors, were associated with white blood cell telomere length at age 49–51 years.MethodsThe study included 318 members of the Newcastle Thousand Families Study, a prospectively followed birth cohort which includes all individuals born in Newcastle, England in May and June 1947, who attended for clinical examination at age 49–51 years, and had telomere length successfully measured using real-time PCR analyses of DNA extracted from peripheral blood mononuclear cells.ResultsNo association was found between birth weight and later telomere length. However, associations were seen with other factors from early life. Education level was the only predictor in males, while telomere length in females was associated with gestational age at birth, childhood growth and childhood IQ.ConclusionsWhile these findings may be due to chance, in particular where differing associations were seen between males and females, they do provide evidence of early life associations with telomere length much later in life. Our findings of sex differences in the education association may reflect the sex differences in achieved education levels in this generation where few women went to university regardless of their intelligence. Our findings do not support the concept of telomere length being on the pathway between very early growth and later disease risk.

High lead exposure is associated with telomere length shortening in Chinese battery manufacturing plant workers

ObjectivesCritically shortening of telomere length caused by various factors including environmental pollutants results in genome instability and age-associated diseases. Lead is one of the ubiquitous environmental and occupational pollutants, potentially...

Telomere length and its associations with oxidized-LDL carotid artery distensibility and smoking

Oxidative stress is a key factor driving the aging of cells and arteries. Studies suggest that white blood cell (WBC) telomere length is an index of systemic aging. We, therefore, investigated the association between WBC telomere length and oxidized-LDL, and vascular aging, expressed by the distensibility of the carotid artery. We studied a random population sample of 216 non-smokers and 89, smokers. In all subjects, age and gender- adjusted telomere length was inversely correlated with plasma oxidized-LDL (regression coefficient = -0.656 kb/mg/dL; p=0.0006). Independent of gender, age and mean blood pressure, carotid distensibility increased with telomere length (2.33+/- 1.18 10-3/kPa/kb; p=0.05) but decreased with higher plasma levels of oxidized LDL (-10.7+/- 3.91 10-3/kPa/ mg/dL; p=0.006). Adjusted for gender and age, smokers' telomere length was shorter (6.72 vs 6.91 kb; p=0.014) and plasma oxidized-LDL level higher (0.52 vs 0.46 mg/dL; p=0.03) than in non-smokers. Higher level of oxidized-LDL, is associated with shorter WBC telomeres and increased stiffness of the carotid artery. Smoking is marked by increased oxidative stress in concert with shortened WBC telomere length.

The dynamic changing profiles of peripheral white blood cell telomere length in populations of different ages living at different altitude areas

To investigate the relationship between the length of telomere DNA and age at different altitude areas. All 172 peripheral blood samples were randomly selected from healthy individuals of different ages from 25 to 65 years old. High altitude group (47 males, 48 females) living at an altitude of 4380 m (HA group), sea level group (39 males, 38 females) living at an altitude of 43 m (SL group). The terminal restriction fragment (TRF) length of telomere DNA was measured by Southern blotting analysis. The plasma levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were assayed. Average TRF lengths of males and females in HA groups were 10.45 +/- 1.35 and 10.50 +/- 1.45. Average TRF lengths of males and females in SL groups were 11.29 +/- 1.10 and 11.31 +/- 1.13. A negative correlation was shown between the average TRF length and age of males in two groups (P < 0.01). This was also the case for females. ANOVA test was used to analyze the difference between TRF length and gender at different ages (P < 0.001). It was shown that there was significant difference in TRF length between the male (25 years old and 55 years old) and female (25 years old and 55 years old) in two groups at different ages (P < 0.05). The plasma levels of SOD and MDA were significant different between HA groups and SL groups (25-44 years old groups/45-65 years old groups) (P < 0.05). Obviously shortening of telomere was observed by increasing of ages in high altitude groups. There was a negative correlation between the length of telomere DNA and ages. Telomere shortening became more obviously in high altitude group than in sea level group in keeping with the age increases.

Expanding the Concept of Telomere Dysfunction in Cardiovascular Disease

Cellular repair and regeneration are considered important features of cardiovascular homeostasis. Exhaustion of these processes and replicative senescence during aging may promote cardiovascular diseases.1 This concept has recently received support from studies that used telomere length as a marker of biological aging and predictor of replicative senescence.1 Further studies show that shorter telomere length, which indicates older cells, is associated with several types of cardiovascular diseases including atherosclerosis2 and heart failure3 (Figure). Most of the studies to date have used white blood cell telomere length as a marker of ageing, but these might not necessarily be the most relevant cells to study. Figure. A, Telomeres (red) are located on the extreme ends of the chromosome (green). B, Hypothetical effects on BM stem cells, lymphocytes, and granulocytes of known factors determining telomere length, include replicative stress, risk factors (eg, oxidative stress), and the strong genetic determinant. C, The potential levels on which the association between telomere length and the cardiovascular disease continuum (D) may lie. BM indicates bone marrow; WBC, white blood cells, CAD, coronary artery disease; CHF, chronic heart failure. See accompanying article on page 968 There is evidence that cells originating from …

Telomere length in white blood cells, buccal cells and brain tissue and its variation with ageing and Alzheimer's disease

Changes in telomere length have been associated with ageing and with certain age-related degenerative diseases. We report results using a quantitative RTm-PCR method to measure absolute telomere length (in kb per diploid genome) and show the age-related changes in white blood cells and buccal cell telomere length (in kb per diploid genome) in normal healthy individuals and Alzheimer's patients. We observed a significantly lower telomere length in white blood cells ( P < 0.0001) and buccal cells ( P < 0.01) in Alzheimer's patients relative to healthy age-matched controls (31.4% and 32.3%, respectively). However, there was a significantly greater telomere length in hippocampus cells of Alzheimer's brains ( P = 0.01) compared to control samples (49.0%). We also observed that telomere length in buccal cells was 52.2–74.2% shorter than that observed in white blood cells ( P < 0.0001). The odd's ratio of being diagnosed with Alzheimer's disease (AD) was 10.8 (95% CI 1.19–97.85) if white blood cell telomere length was less than 115 kb per diploid genome with a specificity of 46% and sensitivity of 92.9%. The odds ratio for AD diagnosis was 4.6 (95% CI 1.22–17.16) if buccal cell telomere length was less than 40 kb per diploid genome with a sensitivity of 72.7% and a specificity of 63.1%. These results suggest important differences in telomere maintenance in Alzheimer's cases compared to healthy controls depending on sampled tissue. These results need to be replicated in larger studies and in cohorts of other neurodegenerative disorders to determine specificity of changes to Alzheimer's patients.

Short Telomere Length and Breast Cancer Risk: A Study in Sister Sets

Telomeres consist of a tandem repeats of the sequence TTAGGG at the ends of chromosomes and play a key role in the maintenance of chromosomal stability. Previous studies indicated that short telomeres are associated with increased risk for human bladder, head and neck, lung, and renal cell cancer. We investigated the association between white blood cell telomere length and breast cancer risk among 268 family sets (287 breast cancer cases and 350 sister controls). Telomere length was assessed by quantitative PCR. The mean telomere length was shorter in cases (mean, 0.70; range, 0.03-1.95) than in unaffected control sisters (mean, 0.74; range, 0.03-2.29), but no significant difference was observed (P = 0.11). When subjects were categorized according to the median telomere length in controls (0.70), affected sisters had shorter telomeres compared with unaffected sisters after adjusting for age at blood donation and smoking status [odds ratio (OR), 1.3; 95% confidence interval (95% CI), 0.9-1.8], but the association was not statistically significant. The association by quartile of telomere length (Q4 shortest versus Q1 longest) also supported an increase in risk from shorter telomere length, although the association was not statistically significant (OR, 1.6; 95% CI, 0.9-2.7). This association was more pronounced among premenopausal women (OR, 2.1; 95% CI, 0.8-5.5) than postmenopausal women (OR, 1.3; 95% CI, 0.5-3.6 for Q4 versus Q1). If these associations are replicated in larger studies, they provide modest epidemiologic evidence that shortened telomere length may be associated with breast cancer risk.

No association between socio‐economic status and white blood cell telomere length

It has been hypothesized that more socio-economically deprived individuals age faster and, thus, have shorter telomeres than their more affluent counterparts. A weak association between white blood cell telomere length and socio-economic status in a large heterogeneous sample of females has recently been reported. In 318 individuals from a homogeneous birth cohort, we found no evidence of an association between any measure of socio-economic status and peripheral blood mononucleocyte telomere length at age 50 after control for lifestyle variables, gender and paternal age at birth. The results of this, and the previous study, suggest that there is little evidence of a strong or consistent correlation between white blood cell telomere length and markers of socio-economic status.

The effects of social status on biological aging as measured by white‐blood‐cell telomere length

Low socio-economic status (SES) is associated with a shortened life expectancy, but its effect on aging is unknown. The rate of white-blood-cell (WBC) telomere attrition may be a biological indicator of human aging. We tested the hypothesis that SES is associated with telomere attrition independent of known risk factors influencing the aging process. We studied 1552 female twins. A venous blood sample was taken from each twin and isolated WBCs used for extraction of DNA. Terminal restriction fragment length (TRFL) was measured. Questionnaire data were collected on occupation, education, income, smoking, exercise, height and weight. Standard multiple linear regression and multivariate analyses of variance tested for associations between SES and TRFL, adjusting for covariates. A discordant twin analysis was conducted on a subset to verify findings. WBC telomere length was highly variable but significantly shorter in lower SES groups. The mean difference in TRFL between nonmanual and manual SES groups was 163.2 base pairs (bp) of which 22.9 bp (approximately 14%) was accounted for by body mass index, smoking and exercise. Comparison of TRFL in the 17 most discordant SES twin pairs confirmed this difference. Low SES, in addition to the harmful effects of smoking, obesity and lack of exercise, appears to have an impact on telomere length.

Aldosterone and Telomere Length in White Blood Cells

Aldosterone accelerates cardiovascular aging by mechanisms that generate reactive oxygen species. Telomere length in white blood cells (WBCs) may be a bioindicator that registers the accruing burden of systemic oxidative stress. The aim of the present study was, therefore, to examine the relationship between plasma aldosterone and telomere length in WBCs. We studied 75 normotensive and never-treated mildly hypertensive men whose blood was drawn for the measurements of plasma aldosterone concentration and the terminal restriction fragment (TRF) length in WBCs. The slope of the TRF-age relationship in the entire cohort showed a decrease in telomere length of 26 +/- 5 base pairs per year (r = -0.46, p <.001). Age-adjusted TRF length was the longest in the lowest aldosterone quartile (6.74 +/- 0.12 kb) and shortest in the highest aldosterone quartile (6.36 +/- 0.11 kb), with intermediate TRF lengths in the second and third aldosterone quartiles (analysis of variance [ANOVA] trend test, p =.025). In telomeric attrition equivalence, participants in the upper aldosterone quartile were 15 years older than their peers in the lowest quartile. The inverse relationship between aldosterone and WBC telomere length suggests not only that aldosterone is pro-oxidant but that elevated concentrations of this hormone might be linked to a higher rate of telomere attrition and perhaps increased biological aging in humans.