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1.
Age-associated telomere shortening is a well documented feature of peripheral blood cells in human population studies, but it is not known to what extent these data can be transferred to the individual level. Telomere length (TL) in two blood samples taken at ~10 years interval from 959 individuals was investigated using real-time PCR. TL was also measured in 13 families from a multigenerational cohort. As expected, we found an age-related decline in TL over time (r=–0.164, P<0.001, n=959). However, approximately one-third of the individuals exhibited a stable or increased TL over a decade. The individual telomere attrition rate was inversely correlated with initial TL at a highly significant level (r=–0.752, P<0.001), indicating that the attrition rate was most pronounced in individuals with long telomeres at baseline. In accordance, the age-associated telomere attrition rate was more prominent in families with members displaying longer telomeres at a young age (r=–0.691, P<0.001). Abnormal blood TL has been reported at diagnosis of various malignancies, but in the present study there was no association between individual telomere attrition rate or prediagnostic TL and later tumor development. The collected data strongly suggest a TL maintenance mechanism acting in vivo, providing protection of short telomeres as previously demonstrated in vitro. Our findings might challenge the hypothesis that individual TL can predict possible life span or later tumor development.  相似文献   

2.
Telomere length (TL) is considered a marker of biological aging and has been associated with the presence of various coronary risk factors in patients. Much less is known about the relationships between TL and classic coronary risk factors in other populations. We measured TL in peripheral blood leukocytes of 343 middle-aged blood donors (mean age 40.2 ± 12.4 years; 201 men, 142 women) using quantitative polymerase chain reaction. Median TL was 0.86 (range: 0.48–1.85) relative TL units. In linear regression analyses with natural log-transformed T to S ratio as the dependent variable, there was a significant association with age (per year: beta = -0.007, p<0.001) and sex (males vs. females: beta = 0.075, p = 0.007) with longer telomeres in men. After adjusting for these two variables, we observed no association of TL with classic coronary risk factors including cholesterol (p = 0.36), triglyceride (p = 0.09), HDL-cholesterol (p = 0.26), LDL-cholesterol (p = 0.36), smoking (p = 0.97), and personal (p = 0.46) or family history (p = 0.63) of cardiovascular disease. However, we did find a significant positive association with white (p = 0.011) and red blood cell count (p = 0.031), hemoglobin (p = 0.014) and hematocrit (p = 0.013); we also found a borderline positive association with thrombocytes (p = 0.074). Positive associations remained significant for hemoglobin (p = 0.017), hematocrit (p = 0.023), and leukocytes (p = 0.009) in a subgroup with no reported vascular disease; associations were of borderline significance for erythrocytes (p = 0.053) and thrombocytes (p = 0.088) in this subgroup. The data do not support the concept that classic coronary risk factors contribute to telomere attrition in a blood donor population. However, telomere attrition may be a marker for reduced proliferation reserve in hematopoietic progenitor cells.  相似文献   

3.

Aims

Interindividual variability in telomere length is highly heritable. Leukocyte telomere length (LTL) shortening has been shown to be associated with the process of atherosclerosis. But whether the inheritance of LTL is related to stroke is still unclear. The aim of this study was to test if telomere shortening was associated with stroke and whether this association was mainly due to inheritance or acquired cardiovascular risk factors.

Methods

Our study was focused on stroke in patients and their siblings. 450 subjects were recruited into this study: 150 patients with ischemic stroke as case group, 150 siblings of patients free of stroke (sibling group) and 150 healthy people as normal control. LTL was measured by real-time Polymerase Chain Reactions. The association between LTL and the cardiovascular risk factors was also determined.

Results

A significant decrease of LTL was found in case group when comparing with sibling (0.92±0.77 vs 1.68±1.24, p<0.001) and normal groups (0.92±0.77 vs 1.95±1.07, p<0.001), but no significant difference was found between sibling group and healthy control (p = 0.330). Shorter telomere length was independently associated with hypertension (p = 0.029, OR = 2.189, 95%CI:1.084–4.421), recent social pressure (p = 0.001, OR = 3.121, 95%CI:1.597–6.101), age (p = 0.004, OR = 1.055, 95%CI:1.017–1.093), HDL (p = 0.022, OR = 0.227, 95%CI:0.064–0.810) and diabetes (p = 0.018, OR = 3.174, 95%CI:1.221–8.252). Additionally, shortened length of telomere (p = 0.017, OR = 3.996, 95%CI:1.283–12.774) was an independent risk biomarker for stroke among case and sibling groups.

Conclusion

The present study has demonstrated that decreased LTL might be associated with ischemic stroke but unlikely to be causative.  相似文献   

4.
Red blood cell distribution width (RDW) is one of the routine hematologic parameters reported in the complete blood count test, which has been recognized as strong prognostic marker for various medical conditions, especially cardiovascular disease. We evaluated that RDW was also associated with the leukoaraiosis; common radiological finding of brain and that has been strongly associated with risk of stroke and dementia. In the present study, we included 1006 non-stroke individuals who underwent brain MRI and routine complete blood count test including RDW. Fazekas scale was used to measure the severity of leukoaraiosis based on fluid-attenuated inversion recovery image, and the severity was dichotomized to mild-degree (Fazekas scale: 0–1) and severe-degree leukoaraiosis (Fazekas scale: 2–3). Univariate and multivariate logistic regression models were constructed to evaluate independent risk factor for severe-degree of leukoaraiosis. Mean age of 1006 subjects was 64.34 ± 9.11 year, and mean of RDW was 12.97 ± 0.86%. The severe-degree of leukoaraiosis (Fazekas scale ≥ 2) was found in 28.83%. In the multivariate logistic regression, 4th quartile of RDW (> 13.3%) were significantly associated with the presence of severe-degree of leukoaraiosis (adjusted odds ratio, 1.87; 95% confidence interval, 1.20–2.92) compared to the 1st quartile of RDW (< 12.5%). The significance was not changed after adjustments for hemoglobin and other hematologic indices. These findings suggest that RDW is independently associated with severity of leukoaraiosis.  相似文献   

5.

Background

Microbial exposures have been suggested to confer protection from allergic disorders and reduced exposures to gastrointestinal microbiota have been proposed as an explanation for the increase in asthma prevalence. Since the general prevalence of Helicobacter pylori has been decreasing, we hypothesized that H. pylori serostatus would be inversely related to the presence of asthma.

Methods

Adults were recruited to participate in the New York University (NYU)/Bellevue Asthma Registry in New York City. Adult asthma cases (N = 318) and controls (N = 208) were identified and serum IgG antibodies to H. pylori whole cell antigens or the immunodominant CagA antigen were measured.

Results

As expected, the asthma cases and controls differed with respect to atopy and lung function. Seropositivity to H. pylori or CagA antigen was present in 47.1% of the total case and control study population. Asthma was inversely associated with CagA seropositivity (OR = 0.57, 95% CI = 0.36–0.89). Median age of onset of asthma (doctor''s diagnosis) was older (21 years) among individuals with CagA+ strains than among H. pylori- individuals (11 years) (p = 0.006).

Conclusion

These data are consistent with the hypothesis that colonization with CagA+ H. pylori strains is inversely associated with asthma and is associated with an older age of asthma onset in an urban population. The data suggest H. pylori as a marker for protection.

Trial Registration

ClinicalTrials.gov NCT00212537  相似文献   

6.
The serotonin transporter gene (5-HTT)-linked polymorphic region (5-HTTLPR) plays an important role in modulating mood and behavior by regulating 5-HTT expression and thereby controlling the concentration of serotonin (5-HT) in brain synapses: The homozygous shorter allele (S/S) in 5-HTTLPR results in lower 5-HTT expression coupled with stronger psycho-pathological reactions to stressful experiences compared to the homozygous long (L/L) and heterozygous (S/L) alleles. Psychological insults and mood disorders have been shown to cause accelerated telomere shortening, a marker of biological aging, however, it is currently unclear whether the allelic variants of 5-HTTLPR affect telomere length (TL) in the healthy population without mood disorders. In the present study, we determined the relationship between TL and the 5-HTTLPR variants in healthy Han Chinese. The 5-HTTLPR genotyping and leukocyte TL analysis of 280 young female Han Chinese freshmen showed a significantly shorter TL in 149 of them carrying the 5-HTTLPR S/S version compared to those (131) with the L/S or L/S plus L/L genotypes (mean ± SD, 0.533±0.241 for S/S vs 0.607±0.312 for L/S, P  =  0.034; or vs 0.604±0.313 for L/S plus L/L, P  =  0.038). Similar results were achieved in the other cohort including 220 adult healthy individuals of different age, gender and profession (0.691±0.168 for S/S vs 0.729±0.211 for L/S, P  =  0.046, or vs 0.725±0.213 for L/S plus L/L, P  =  0.039). Taken together, shorter leukocyte TL is significantly associated with the 5-HTTLPR S/S allelic variant, which may be implicated in psychological stress-related health problems.  相似文献   

7.
The majority of human telomere length studies have focused on the overall length of telomeres within a cell. In fact, very few studies have examined telomere length for individual chromosome arms. The objective of this study was to examine the relationship between chromosome arm size and the relative length of the associated telomere. Quantitative Fluorescence In Situ Hybridization (Q-FISH) was used to measure the relative telomere length of each chromosome arm in metaphases from cultured lymphocytes of 17 individuals. A statistically significant positive correlation (r = 0.6) was found between telomere length and the size of the associated chromosome arm, which was estimated based on megabase pair measurements from http://www.ncbi.nlm.nih.gov/projects/mapview/.  相似文献   

8.

Background

A link between severe mental stress and shorter telomere length (TL) has been suggested. We analysed the impact of Posttraumatic Stress Disorder (PTSD) on TL in the general population and postulated a dose-dependent TL association in subjects suffering from partial PTSD compared to full PTSD.

Methods

Data are derived from the population-based KORA F4 study (2006–2008), located in southern Germany including 3,000 individuals (1,449 men and 1,551 women) with valid and complete TL data. Leukocyte TL was measured using a quantitative PCR-based technique. PTSD was assessed in a structured interview and by applying the Posttraumatic Diagnostic Scale (PDS) and the Impact of Event Scale (IES). A total of 262 (8.7%) subjects qualified for having partial PTSD and 51 (1.7%) for full PTSD. To assess the association of PTSD with the average TL, linear regression analyses with adjustments for potential confounding factors were performed.

Results

The multiple model revealed a significant association between partial PTSD and TL (beta = −0.051, p = 0.009) as well as between full PTSD and shorter TL (beta = −0.103, p = 0.014) indicating shorter TL on average for partial and full PTSD. An additional adjustment for depression and depressed mood/exhaustion gave comparable beta estimations.

Conclusions

Participants with partial and full PTSD had significantly shorter leukocyte TL than participants without PTSD. The dose-dependent variation in TL of subjects with partial and full PTSD exceeded the chronological age effect, and was equivalent to an estimated 5 years in partial and 10 years in full PTSD of premature aging.  相似文献   

9.

Objective

Higher values of red blood cell distribution width (RDW) have been found in non-surviving than in surviving septic patients. However, it is unknown whether RDW during the first week of sepsis evolution is associated with sepsis severity and early mortality, oxidative stress and inflammation states, and these were the aims of the study.

Methods

We performed a prospective, observational, multicenter study in six Spanish Intensive Care Units with 297 severe septic patients. We measured RDW, serum levels of malondialdehyde (MDA) to assess oxidative stress, and tumour necrosis factor (TNF)-α to assess inflammation at days 1, 4, and 8. The end-point was 30-day mortality.

Results

We found higher RDW in non-surviving (n = 104) than in surviving (n = 193) septic patients at day 1 (p = 0.001), day 4 (p = 0.001), and day 8 (p = 0.002) of ICU admission. Cox regression analyses showed that RDW at day 1 (p<0.001), 4 (p = 0.005) and 8 (p = 0.03) were associated with 30-day mortality. Receiver operating characteristic curves showed that RDW at day 1 (p<0.001), 4 (p<0.001), and 8 (p<0.001) could be used to predict 30-day mortality. RDW showed a positive correlation with serum MDA levels at day 1 and day 4, with serum TNF-α levels at days 4 and 8, and with SOFA score at days 1, 4 and 8.

Conclusions

The major findings of our study were that non-surviving septic patients showed persistently higher RDW during the first week of ICU stay than survivors, that RDW during the first week was associated with sepsis severity and mortality, that RDW during the first week could be used as biomarker of outcome in septic patients, and that there was an association between RDW, serum MDA levels, and serum TNF-α levels during the first week.  相似文献   

10.

Introduction

With advancing age the left ventricle (LV) undergoes structural and functional changes, thereby creating the substrate for the development of diseases. One possible mechanism of the ageing heart is a cellular senescence. Leukocyte telomere length (LTL) is a marker of replicative ageing. The purpose of this study was to evaluate the structure and function of the LV in people of different ages free of cardiovascular diseases (CVD) and regular drug medication and to assess their relationship with LTL. We hypothesized that age-related changes in LV myocardium are associated with telomere length.

Methods

The study population consisted of 150 healthy, non-obese volunteers aged 28 to 78 years without history of CVD, significant deviations by 12-lead electrocardiogram and negative exercise test (treadmill stress test). All the participants underwent standardized transthoracic echocardiography using an available system (iE33; Philips). The LTL was measured by real-time quantitative polymerase chain reaction. We determined the relative ratio of telomere repeat copy number (T) to single-copy gene copy number (S).

Results

In the older people there was a higher wall thickness than in the younger (1.03±0.09 vs. 0.88±0.10, p<0.01), whereas LV mass index was comparable between them (85.8±15.40 vs. 83.1±11.8, p = 0.20). There was a decrease in LV dimensions with advancing age (p<0.001). Older subjects had impairment in LV relaxation. LTL was associated with decreased E/A, Em/Am ratio (β = -0.323, p = 0.0001) after adjusting for age, sex and risk factors. There is no relation between the LTL and the structure of LV.

Conclusions

Our data suggest that the ageing process leads to changes in LV structure and diastolic function and is linked with a phenotype of concentric LV remodeling. Telomere attrition is associated with age-related LV diastolic dysfunction. Telomere length appears to be a biomarker of myocardial ageing.  相似文献   

11.
Serotonin (5-HT) is a monoamine originally purified from blood as a vasoactive agent. In nonneuronal tissues, its presence is linked with the expression of tryptophan hydroxylase 1 (TPH1) that catalyzes the rate-limiting step of its synthesis. Targeted disruption in mice of the TPH1 gene results in very low levels of circulating 5-HT. Previous analysis of the TPH1 knockout (TPH1−/−) mouse revealed that they develop a phenotype of macrocytic anemia with a reduced half-life of their circulating red blood cells (RBC). In this study, to establish whether the observed reduced half-life of TPH1−/− RBC is an intrinsic or an extrinsic characteristic, we compared their survival to RBC isolated from wild-type mice. Both in vivo and in vitro data converge to demonstrate an extrinsic protective effect of 5-HT since presence of 5-HT in the RBC environment protects RBC from senescence. The protective effect played by 5-HT is not mediated through activation of a classical pharmacological pathway as no 5-HT receptors were detected on isolated RBC. Rather, 5-HT acts as an effective antioxidant since reduction of 5-HT circulating levels are associated with a decrease in the plasma antioxidant capacity. We further demonstrate a link between oxidation and the removal of damaged RBC following transfusion, as supplementation with 5-HT improves RBC post-transfusion survival in a mouse model of blood banking.  相似文献   

12.
13.

Background and Aims

Joint association of lifestyle-related factors and mental health has been less studied in earlier studies, especially in Middle Eastern countries. This study aimed to examine how combinations of several lifestyle-related factors related to depression and anxiety in a large group of middle-age Iranian population.

Methods

In a cross-sectional study on 3363 Iranian adults, a healthy lifestyle score was constructed by the use of data from dietary intakes, physical activity, smoking status, psychological distress and obesity. A dish-based 106-item semi-quantitative validated food frequency questionnaire (FFQ), General Practice Physical Activity Questionnaire (GPPAQ), General Health Questionnaire (GHQ) and other pre-tested questionnaires were used to assess the components of healthy lifestyle score. The Hospital Anxiety and Depression Scale (HADS) was applied to screen for anxiety and depression.

Results

After adjustment for potential confounders, we found that individuals with the highest score of healthy lifestyle were 95% less likely to be anxious (OR: 0.05; 95% CI: 0.01–0.27) and 96% less likely to be depressed (OR: 0.04; 95% CI: 0.01–0.15), compared with those with the lowest score. In addition, non-smokers had lower odds of anxiety (OR: 0.64; 95% CI: 0.47–0.88) and depression (OR: 0.62; 95% CI: 0.48–0.81) compared with smokers. Individuals with low levels of psychological distress had expectedly lower odds of anxiety (OR: 0.13; 95% CI: 0.10–0.16) and depression (OR: 0.10; 95% CI: 0.08–0.12) than those with high levels. Individuals with a healthy diet had 29% lower odds of depression (OR: 0.71; 95% CI: 0.59–0.87) than those with a non-healthy diet.

Conclusion

We found evidence indicating that healthy lifestyle score was associated with lower odds of anxiety and depression in this group of Iranian adults. Healthy diet, psychological distress, and smoking status were independent predictors of mental disorders.  相似文献   

14.
15.

Background

Major depressive disorder (MDD) is the leading cause of disability worldwide, and has significant genetic predisposition. Mitochondria may have a role in MDD and so mitochondrial DNA (mtDNA) has been suggested as a possible biomarker for this disease. We aimed to test whether the mtDNA copy number of peripheral blood leukocytes is related to MDD in young adults.

Methods

A case-control study was conducted with 210 MDD patients and 217 healthy controls (HC). The mtDNA copy number was measured by quantitative polymerase chain reaction (qPCR) method. Depression severity was assessed by the Hamilton-17 Depression Rating Scale (HDRS-17).

Results

We found no significant differences in mtDNA copy number between MDD patients and HC, though the power analysis showed that our sample size has enough power to detect the difference. There were also no significant correlations between mtDNA copy number and the clinical characteristics (such as age, age of onset, episodes, Hamilton Depression Rating Scale (HDRS) score and Global Assessment of Function Scale (GAF) score) in MDD patients.

Conclusion

Our study suggests that leukocyte mtDNA copy number is unlikely to contribute to MDD, but it doesn’t mean that we can exclude the possibility of involvement of mitochondria in the disease. Further studies are required to elucidate whether mtDNA can be a biomarker of MDD.  相似文献   

16.

Background

Premature shortening of leukocyte telomere length has been proposed as a novel mechanism by which depression may confer increased risk of adverse cardiovascular events. Prior studies demonstrating associations of depression and depressive symptoms with shorter leukocyte telomere length were small, included selected psychiatric outpatients, were based on convenience samples, and/or adjusted for a limited number of possible confounding factors.

Methods and Findings

We examined the associations of depressive symptoms, probable depressive disorder, and specific depressive symptom clusters, as assessed by the Center for Epidemiological Studies—Depression (CES-D) scale, with leukocyte telomere length, measured by using a real-time PCR method, in 2,225 apparently healthy participants from the 1995 Nova Scotia Health Survey population-based study. The mean age was 48.2±18.9 years; 49.9% of participants were female; and the mean CES-D score was 7.4±7.9. The mean telomere length was 5,301±587 base pairs. In an unadjusted model, depressive symptoms were significantly associated with longer leukocyte telomere length (B = 27.6 base pairs per standard deviation increase in CES-D, 95% confidence interval [CI] = 3.1–52.1, p = 0.027). This association was no longer significant after adjustment for age and sex (B = 9.5, 95% CI = −14.6–33.6, p = 0.44) or after further adjustment for body mass index, Framingham risk score and previous history of ischemic heart disease (all p''s≥0.37). Neither probable depressive disorder nor specific depressive symptom clusters were independently associated with leukocyte telomere length.

Conclusions

Concurrent depressive symptoms were not associated with leukocyte telomere length in a large, representative, population-based study.  相似文献   

17.
It has been proposed that the progressive shortening of telomeres in somatic cells eventually results in senescence. Previous experiments have demonstrated that many immortal cell lines have acquired telomerase activity leading to stabilization of telomere length. Telomere dynamics and telomerase activity were examined in the telomerase-positive immortal cell lines HeLa and 293 and subclones derived from them. A mass culture of HeLa cells had a stable mean telomere length over 60 population doublings (PD)in vitro.Subclones of this culture, however, had a range of mean telomere lengths indicating that telomeric heterogeneity exists within a population with a stable mean telomere length. Some of the subclones lacked detectable telomerase activity soon after isolation but regained it by PD 18, suggesting that at least some of the variation in telomere length can be attributed to variations in telomerase activity levels. 293 subclones also varied in telomere length and telomerase activity. Some telomerase-positive 293 subclones contained long telomeres that gradually shortened, demonstrating that factors other than telomerase also act to modulate telomere length. Fluctuations in telomere length in telomerase-positive immortalized cells may contribute to chromosomal instability and clonal evolution.  相似文献   

18.

Background

Shorter telomere length and poor sleep are more prevalent at older ages, but their relationship is uncertain. This study explored associations between sleep duration and telomere length in a sample of healthy middle and early old age people.

Methods

Participants were 434 men and women aged 63.3 years on average drawn from the Whitehall II cohort study. Sleep duration was measured by self-report.

Results

There was a linear association between sleep duration and leukocyte telomere length in men but not in women (P = 0.035). Men reporting shorter sleep duration had shorter telomeres, independently of age, body mass index, smoking, educational attainment, current employment, cynical hostility scores and depressive symptoms. Telomeres were on average 6% shorter in men sleeping 5 hours or fewer compared with those sleeping more than 7 hours per night.

Conclusion

This study adds to the growing literature relating sleep duration with biomarkers of aging, and suggests that shortening of telomeres might reflect mechanisms through which short sleep contributes to pathological conditions in older men.  相似文献   

19.
目的:研究骨肿瘤端粒长度变化与端粒结合蛋白即端粒重复结合因子1(TRF1)和端粒保护因子(POT1),端粒酶催化亚单位(hTERT),肿瘤相关基因P53、c-myc表达的关系,以了解骨肿瘤的分子特征。方法:采用免疫组织化学、端粒定量荧光原位杂交(Telo-FISH)和原位杂交检测了20例骨肉瘤、25例软骨肉瘤、14例骨的纤维结构不良中端粒长度、TRF1、POT1、hTERT、P53、c-myc的表达情况,并进行统计分析。结果:20例骨肉瘤平均长度为0.31,25例软骨肉瘤为0.41,14例骨的纤维结构不良为0.52。统计显示三者间端粒长度有显著差异(P<0.05)。骨肉瘤和软骨肉瘤TRF1、POT1阳性率均显著低于骨纤维结构不良(P<0.05)。而骨肉瘤和软骨肉瘤hTERT基因表达显著高于骨纤维结构不良(P<0.05)。骨肉瘤、软骨肉瘤P53、c-myc阳性率高于骨纤维结构不良(P<0.05)。统计分析骨肿瘤端粒长度变化与端粒结合蛋白TRF1、POT1的表达呈负相关性,与端粒酶hTERT基因表达、与P53蛋白核聚积,以及c-myc癌基因表达呈正相关性。结论:骨肿瘤端粒长度与恶性表型有关、端粒短缩与肿瘤基因突变相关。  相似文献   

20.
Combination antiretroviral therapy (cART) has extended the longevity of human immunodeficiency virus (HIV)-infected individuals. However, this has resulted in greater awareness of age-associated diseases such as chronic obstructive pulmonary disease (COPD). Accelerated cellular senescence may be responsible, but its magnitude as measured by leukocyte telomere length is unknown and its relationship to HIV-associated COPD has not yet been established. We measured absolute telomere length (aTL) in peripheral leukocytes from 231 HIV-infected adults. Comparisons were made to 691 HIV-uninfected individuals from a population-based sample. Subject quartiles of aTL were assessed for relationships with measures of HIV disease severity, airflow obstruction, and emphysema severity on computed tomographic (CT) imaging. Multivariable regression models identified factors associated with shortened aTL. Compared to HIV-uninfected subjects, the mean aTL in HIV-infected patients was markedly shorter by 27 kbp/genome (p<0.001); however, the slopes of aTL vs. age were not different (p=0.469). Patients with longer known durations of HIV infection (p=0.019) and lower nadir CD4 cell counts (p=0.023) had shorter aTL. Shorter aTL were also associated with older age (p=0.026), smoking (p=0.005), reduced forced expiratory volume in one second (p=0.030), and worse CT emphysema severity score (p=0.049). HIV-infected subjects demonstrate advanced cellular aging, yet in a cART-treated cohort, the relationship between aTL and age appears no different from that of HIV-uninfected subjects.  相似文献   

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