Telomere Length In Adults Research Articles

Inverse and Direct Effect of Serum DDE Exposure on the Distribution of Leukocyte Telomere Length in Brazilian Adults: The Pró-Saúde Study

Inverse and Direct Effect of Serum DDE Exposure on the Distribution of Leukocyte Telomere Length in Brazilian Adults: The Pró-Saúde Study

Hypertension Control Is Associated with Telomere Length in Older Adults.

Hypertension is the leading risk for cardiovascular disease and worldwide mortality. Uncontrolled blood pressure worsens with age and its control is part of public health strategies especially for older adults. Telomere length (TL) has been associated with hypertension, with age and sex as relevant confounding factors, but it is not clear whether hypertension control in older adults impacts on TL and if this relationship is consistently age and sex dependent. TL was assessed in leukocytes of 369 hypertensive patients. Individuals were >60 years male (169) and female (200) and have been diagnosed and treated for hypertension for at least four years. TL was measured by RT-PCR using a commercial probe. Regression models were developed considering systolic and diastolic blood pressure control as dependent variables and age, sex, glucose, and lipid levels as confounding factors. TL showed a mean of 7.5 ± 5.1 Kb, and no difference between males and females was observed. We identified a significant association between systolic blood pressure control and TL (p value = 0.039) and a trend for diastolic blood pressure (p value = 0.061). These observations confirm and expand previous reports showing that hypertension control can have an impact on TL and consequently on other factors of healthy aging.

Sex-specific modulating role of social support in the associations between oxidative stress, inflammation, and telomere length in older adults.

Telomere length, a biomarker of human aging, is related to adverse health outcomes. Growing evidence indicates that oxidative stress and inflammation contributes to telomere shortening, whereas social support may protect from telomere shortening. Despite sex differences in telomere length and social support, little is known about whether there are sex differences in the relationship between oxidative stress/inflammation and telomere length, and sex-specific moderating roles of social support in older adults. Using data from the National Health and Nutrition Examination Survey (NHANES) 1999-2002, this study assessed whether the associations between oxidative stress/inflammation and telomere length vary with sex and explored social support as a moderator in these associations among 2289 older adults. Oxidative stress was measured based on serum Gamma-glutamyl transferase (GGT), and inflammation was measured based on C-reactive protein (CRP). After adjusting for the covariates, GGT was significantly associated with telomere length in females only (β = - 0.037, 95% CI = - 0.070, - 0.005), while CRP was associated with telomere length in males only (β = - 0.019, 95% CI = - 0.035, - 0.002). Moreover, high social support mitigated the negative association between GGT and telomere length, which was more evident in females. Furthermore, social support moderated the association between CRP and telomere length in males aged 70 and above. Our findings indicated that biological mechanisms related to telomere length may vary with sex, while social support plays a sex-specific moderating role.

Telomere length is longer following diapause in two solitary bee species

The mechanisms that underlie senescence are not well understood in insects. Telomeres are conserved repetitive sequences at chromosome ends that protect DNA during replication. In many vertebrates, telomeres shorten during cell division and in response to stress and are often used as a cellular marker of senescence. However, little is known about telomere dynamics across the lifespan in invertebrates. We measured telomere length in larvae, prepupae, pupae, and adults of two species of solitary bees, Osmia lignaria and Megachile rotundata. Contrary to our predictions, telomere length was longer in later developmental stages in both O. lignaria and M. rotundata. Longer telomeres occurred after emergence from diapause, which is a physiological state with increased tolerance to stress. In O. lignaria, telomeres were longer in adults when they emerged following diapause. In M. rotundata, telomeres were longer in the pupal stage and subsequent adult stage, which occurs after prepupal diapause. In both species, telomere length did not change during the 8 months of diapause. Telomere length did not differ by mass similarly across species or sex. We also did not see a difference in telomere length after adult O. lignaria were exposed to a nutritional stress, nor did length change during their adult lifespan. Taken together, these results suggest that telomere dynamics in solitary bees differ from what is commonly reported in vertebrates and suggest that insect diapause may influence telomere dynamics.

Effect of long-term caloric restriction on telomere length in healthy adults: CALERIE™ 2 trial analysis.

Caloric restriction (CR) modifies lifespan and aging biology in animal models. The Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy (CALERIE™) 2 trial tested translation of these findings to humans. CALERIE™ randomized healthy, nonobese men and premenopausal women (age 21-50y; BMI 22.0-27.9 kg/m2), to 25% CR or ad-libitum (AL) control (2:1) for 2 years. Prior analyses of CALERIE™ participants' blood chemistries, immunology, and epigenetic data suggest the 2-year CR intervention slowed biological aging. Here, we extend these analyses to test effects of CR on telomere length (TL) attrition. TL was quantified in blood samples collected at baseline, 12-, and 24-months by quantitative PCR (absolute TL; aTL) and a published DNA-methylation algorithm (DNAmTL). Intent-to-treat analysis found no significant differences in TL attrition across the first year, although there were trends toward increased attrition in the CR group for both aTL and DNAmTL measurements. When accounting for adherence heterogeneity with an Effect-of-Treatment-on-the-Treated analysis, greater CR dose was associated with increased DNAmTL attrition during the baseline to 12-month weight-loss period. By contrast, both CR group status and increased CR were associated with reduced aTL attrition over the month 12 to month 24 weight maintenance period. No differences were observed when considering TL change across the study duration from baseline to 24-months, leaving it unclear whether CR-related effects reflect long-term detriments to telomere fidelity, a hormesis-like adaptation to decreased energy availability, or measurement error and insufficient statistical power. Unraveling these trends will be a focus of future CALERIE™ analyses and trials.

The association of sleep duration and leukocyte telomere length in middle-aged and young-old adults: A cross-sectional study of UK Biobank

BackgroundThe relationships between sleep duration and aging-associated diseases are intricate. Leukocyte telomere length (LTL) is a biomarker of aging, while the association of sleep duration and LTL is unclear. MethodsThe 310,091 study participants from UK Biobank were enrolled in this cross-sectional study. Restricted cubic splines (RCS) analysis was firstly performed to assess the nonlinear relationship between sleep duration and LTL. Sleep duration was then categorized into three groups: <7 h (short sleep duration), 7–8 h (reference group), and >8 h (long sleep duration) and multiple linear regression was applied to analyze the association of short sleep and long sleep duration with LTL. We further performed subgroup analyses stratified by sex, age, chronotype and snoring. ResultsRCS showed an inverted J-shaped relationship between sleep duration and LTL. Compared with the reference group, the inverse association of long sleep duration and LTL was statistically significant in fully-adjusted model (P = 0.001). Subgroup analyses showed that this association was more apparent in people over 50 years (51–60 y: P = 0.002; >60 y: P = 0.005), in men (P = 0.022), and in people preferred evening chronotype (P = 0.001). ConclusionCompared with participants sleeping 7–8 h, those sleep longer than 8 h had shorter LTL in middle-aged and young-old adults. The negative association between long sleep duration and LTL was more apparent in older people, in men, and in people preferred evening chronotype.

Methamphetamine use shortens telomere length in male adults and rats

BackgroundMethamphetamine (MA) use increases the risk of age-related diseases. However, it remains uncertain whether MA use exhibits accelerated biological aging, as indicated by telomere length (TL), a proposed marker of aging. Here we conducted studies in both humans and rats to investigate the association between MA use and TL. MethodsWe recruited 125 male MA users and 66 healthy controls, aged 30–40 years. MA users were diagnosed using DSM-5 criteria and categorized into two groups: non-severe (n = 78) and severe (n = 47) MA use disorder (MUD). MA-treated conditioned place preference (CPP) rats were utilized to validate our clinical investigations. TL was assessed using real-time polymerase chain reaction. ResultsAt clinical levels, MA users exhibited significantly shorter leukocyte TL compared to healthy controls. Among MA users, individuals with severe MUD had significantly shorter leukocyte TL than those with non-severe MUD. Importantly, both univariate and multivariate linear regression analyses demonstrated a negative association between the severity of MA use and leukocyte TL. In a rat model of MA-induced CPP, leukocyte TL was also significantly shortened after MA administration, especially in rats with higher CPP expression or reinstatement scores. ConclusionMA use shortened TL, and the severity of MA use was negatively correlated with TL. These findings provide new insights into the pathophysiology of accelerated aging caused by MA use and may have implications for identifying biomarkers and developing novel treatment strategies for MUD.

Effects of Physical Exercise on Telomere Length in Healthy Adults: Systematic Review, Meta-Analysis, and Meta-Regression.

Physical exercise is one of the main nonpharmacological treatments for most pathologies. In addition, physical exercise is beneficial in the prevention of various diseases. The impact of physical exercise has been widely studied; however, existing meta-analyses have included diverse and heterogeneous samples. Therefore, to our knowledge, this is the first meta-analysis to evaluate the impact of different physical exercise modalities on telomere length in healthy populations. In this review, we aimed to determine the effect of physical exercise on telomere length in a healthy population through a meta-analysis of randomized controlled trials. A systematic review with meta-analysis and meta-regression of the published literature on the impact of physical exercise on telomere length in a healthy population was performed. PubMed, Cochrane Library, SCOPUS, Web of Science, and Embase databases were searched for eligible studies. Methodological quality was evaluated using the Risk Of Bias In Nonrandomized Studies of Interventions and the risk-of-bias tool for randomized trials. Finally, the certainty of our findings (closeness of the estimated effect to the true effect) was evaluated using Grading of Recommendations, Assessment, Development, and Evaluations (GRADE). We included 9 trials that met the inclusion criteria with fair methodological quality. Random-effects model analysis was used to quantify the difference in telomere length between the exercise and sham groups. Meta-analysis showed that exercise did not significantly increase telomere length compared with the control intervention (mean difference=0.0058, 95% CI -0.05 to 0.06; P=.83). Subgroup analysis suggested that high-intensity interventional exercise significantly increased telomere length compared with the control intervention in healthy individuals (mean difference=0.15, 95% CI 0.03-0.26; P=.01). Furthermore, 56% of the studies had a high risk of bias. Certainty was graded from low to very low for most of the outcomes. The findings of this systematic review and meta-analysis suggest that high-intensity interval training seems to have a positive effect on telomere length compared with other types of exercise such as resistance training or aerobic exercise in a healthy population. PROSPERO CRD42022364518; http://tinyurl.com/4fwb85ff.

Genetically Regulated Telomere Length Relates to Brain Amyloidosis

AbstractBackgroundIt is well‐established that telomeres shrink over the course of aging and that this process is genetically regulated. Work from our group and others has highlighted the complex interplay between measured leukocyte telomere length and Alzheimer’s Disease (AD) biomarkers over the course of AD. We expand on this work to explore whether a polygenic score predicting telomere length relates to PET measures of brain amyloidosis in the preclinical stages of disease.MethodA Polygenic Risk Score (PRS) of telomere length was built from a published GWAS on telomere length from UK Biobank (N = 472,174). We leveraged genetic data from non‐Hispanic White participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI; N = 1,414) and the Anti‐Amyloid Treatment in Asymptomatic Alzheimer’s study (A4; N = 3,002). The relation of the score to measured telomere length was validated using leukocyte telomere length data from ADNI. A linear regression model was used to evaluate whether the PRS relates to a PET measure of brain amyloidosis in a harmonized dataset including ADNI and A4, with a total sample size of 3,940 after restricting to individuals with both genetic data and amyloid measurements. Covariates included age, sex, and diagnostic status.ResultAs expected, telomere PRS related to measured telomeres in ADNI when covarying for age, sex, and baseline diagnosis (Figure 1, p = 0.045). Interestingly, we also observed a counter intuitive association between genetically predicted telomere length and amyloidosis whereby longer predicted telomere length was associated with higher amyloid burden (Figure 2, β = 1305, p = 0.006).ConclusionA PRS for telomere length modestly relates to measured telomere length in older adults and relates to higher amyloid burden. Previous work from our group has highlighted the interaction between measured telomere length and amyloid status such that the association is counter intuitive among those who are biomarker positive. The present results highlight the exciting possibility that telomere length may relate directly to AD biomarkers and open the opportunity for future work further probing the complex interplay between telomere length and AD biomarkers leveraging this powerful genetic tool.

The consumption of Sechium edule (chayote) has antioxidant effect and prevents telomere attrition in older adults with metabolic syndrome

ABSTRACTObjectiveTo determine the effect of the consumption of Sechium edule (1.5 g/day) for six months on oxidative stress (OxS) and inflammation markers and its association with telomere length (TL) in older adults with metabolic syndrome (MetS).MethodsThe study was conducted in a sample of 48 older adults: placebo (EP) and experimental (EG) groups. Lipoperoxides, protein carbonylation, 8-OHdG, total oxidant status (TOS), SOD, GPx, H2O2 inhibition, total antioxidant status (TAS), inflammatory cytokines (IL6, IL10, TNF-α), and TL were measured before and six months post-treatment.ResultsWe found a significant decrease in the levels of lipoperoxides, protein carbonylation, 8-OHdG, TOS in the EG in comparison PG. Likewise, a significante increase of TAS, IL-6, and IL-10 levels was found at six months post-treatment in EG in comparison with PG. TL showed a statistically significant decrease in PG compared to post-treatment EG.ConclusionsOur findigns showed that the supplementation of Sechium edule has antioxidant, and anti-inflammatory effects, and diminushion of shortening of telomeric DNA in older adults with MetS. This would be the first study that shows that the intervention with Sechium edule has a possible geroprotective effect by preventing telomeres from shortening as usually happens in these patients. Therefore, suggesting a protection of telomeric DNA and genomic DNA.

The Association between Dietary Magnesium Intake and Telomere Length in Adults with Hypertension.

Dietary micronutrients are significantly associated with telomere length, as shown in multiple studies. However, no study has investigated the association between magnesium intake and telomere length in adults with hypertension. Participants were included from the National Health and Nutrition Examination Survey (NHANES) in 1999-2000 and 2001-2002. Dietary magnesium intake was assessed using the 24 - hour recall method and the telomere length of leukocytes was measured using polymerase chain reaction (PCR). A multivariate regression model was then used to assess the association between dietary magnesium intake and telomere length in adults with hypertension. Our final analysis included 2199 hypertensive adults (46.79% males) with a mean dietary magnesium intake of 254.82±133.47 mg/day. Linear regression, adjusted for race, sex, age, smoking, uric acid, and other variables, showed that every 1 mg increase in dietary magnesium intake was associated with a 0.20 (95% CI: 0.01, 0.39, p = 0.043) longer telomere length in all participants. In the ≥45 years age group, there was a statistically significant association between the telomere length and dietary magnesium (95% CI: 0.16, 0.63, p <0.001). This study suggests that increased magnesium intake is associated with a longer telomere length in hypertensive adults, especially in those ≥45 years of age. However, further research is needed to determine a causal relationship.

Association of Social Support Network with Telomere Length: A Cross-Sectional Study with Community-Dwelling Older Adults.

Considering that telomere length can be determined not only by issues related to cell biology but also by aspects related to social factors and environmental exposures, studies on the relationship between social aspects and telomere length can help to better understand the still scarcely known aspects of the human aging process. Thus, this research seeks to verify whether social support networks are associated with telomere length in older adults. This is a cross-sectional study conducted with 448 individuals aged at least 60 years living in the urban area of an inland Brazilian municipality. Relative quantification of telomere length was obtained through real-time qPCR. Social support was assessed through the Medical Outcomes Study Social Support Scale. Descriptive statistics and multiple logistic regression were used in data analysis. The evaluated social support networks for older adults consist in a mean of 16.4 people, and the percentage of older adults who reported up to five members in their network was 27.75%. Shorter telomere length was identified in 25% of the participants, and the older adults who reported having up to five members in their support network were more likely to have a shorter telomere length than those who reported more numerous networks (odds ratio: 1.89, p = 0.011) regardless of gender, age, household arrangement, cognitive decline, and dependence for basic and instrumental activities of daily living, which suggests that measures that stimulate the creation and maintenance of social support networks should be implemented to improve older adults' health.

The association between visceral adiposity index and leukocyte telomere length in adults: results from National Health and Nutrition Examination Survey.

Leukocyte telomere length (LTL) is a robust marker of biological aging, which is associated with obesity. Recently, the visceral adiposity index (VAI) has been proposed as an indicator of adipose distribution and function. To evaluated the association between VAI and LTL in adult Americans. There were 3193 participants in U.S. National Health and Nutrition Examination Surveys (1999-2002) included in this analysis. LTL was measured using quantitative PCR (qPCR) and expressed as telomere to single-gene copy ratio (T/S ratio). We performed multiple logistic regression models to explore the association between VAI and LTL by adjusting for potential confounders. Among all participants, VAI was associated with the shorter LTL (β: - 14.81, 95% CI - 22.28 to - 7.34, p < 0.001). There were significant differences of LTL in VAI tertiles (p < 0.001). Participants in the higher VAI tertile had the shorter LTL (1.26 ≤ VAI < 2.46: β = - 130.16, 95% CI [ - 183.44, - 76.87]; VAI ≥ 2.46: β = - 216.12, 95% CI [ - 216.12, - 81.42], p for trend: < 0.001) comparing with the lower VAI tertile. We also found a non-linear relationship between VAI and LTL. VAI was negatively correlated with LTL when VAI was less than 2.84. The present study demonstrates that VAI is independently associated with telomere length. A higher VAI is associated with shorter LTL. The results suggest that VAI may provide prediction for LTL and account for accelerating the biological aging.

Higher hair cortisol concentrations associated with shorter leukocyte telomere length in high-risk young adults

Chronic stress is associated with accelerated biological aging as indexed by short age-adjusted leukocyte telomere length (LTL). Exploring links of biological stress responses with LTL has proved challenging due to the lack of biological measures of chronic psychological stress. Hair cortisol concentration (HCC) has emerged as a measure of chronic hypothalamic pituitary adrenal (HPA) axis activation, allowing the examination of relationships between aggregate cortisol concentrations over time and LTL. Our sample includes 92 participants (38% women, Mage = 26 ± 3.7 years) from a high-risk sample of young adults with previous residential care placements. Two cm hair was collected for HCC, reflecting approximately eight weeks of cortisol secretion. LTL was measured with quantitative polymerase chain reaction (qPCR) in whole blood samples. All samples for LTL were run in triplicate and assayed twice. Linear and polynomial regression models were used to describe the association between HCC and LTL, adjusting for age and sex. HCC and LTL showed negative associations (std. ß = − 0.67, 95% CI [− 0.83, − 0.52], p < .001) in age- and sex-adjusted analyses, indicating that higher HCCs are associated with shorter LTL. Using polynomial regression, we found a curvilinear relationship indicating a stronger negative association at lower cortisol concentrations. Higher HCCs were associated with shorter LTL, supporting the hypothesized involvement of prolonged cortisol secretion in telomere attrition. Thus, HCC may prove useful as a biological indicator of chronic stress associated with aging-related processes in samples exposed to high levels of stress.

Triglyceride-Glucose Index Correlate With Telomere Length in Healthy Adults From the National Health and Nutrition Examination Survey.

AimThe present investigation was designed to test the association between leukocyte telomere length (LTL) and two simple markers of insulin resistance, that is, homeostatic model assessment of insulin resistance (HOMA-IR) and triglyceride-glucose (TyG) index in U.S. adults without metabolic diseases.MethodsA total of 6489 U.S. adults without diabetes from NHANES 1999–2002 were analyzed. TyG index was calculated as ln [fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. HOMA-Index was calculated as fasting plasma glucose (mmol/L) × fasting serum insulin (mU/mL)/22.5. LTL was obtained using the quantitative polymerase chain reaction method. Multivariate linear regression analysis was assessed to evaluate the association of TyG index HOMA-IR with LTL. We further conducted a generalized additive model (GAM) and a fitted smoothing curve with penalized spline method.ResultsIt was found that the mean LTL was 5796.1 bp in the measured healthy adults. Overall, TyG index was significantly associated with LTL, while HOMA-IR was not. Compared with participants in tertile 1 of the TyG index, the β (95% CI) for those in the second (8.27 to 8.77) and third (≥ 8.77) were -4.31 (95% CI: -48.12~39.49) and -95.98 (95% CI: -145.08~-46.89), respectively. Subjects with TyG index ≥ 8.77 had statistically significant shorter LTL (β = -93.33, 95%CI: -134.33~-52.32), compared with TyG index < 8.77. We further explored a dose-response relation between TyG index by a decile approach [≤ 7.81 (reference), 7.81-8.04, 8.04-8.21, 8.21-8.37, 8.37-8.52, 8.52-8.68, 8.68-8.83, 8.83-9.03, 9.03-9.33, and >9.33] and LTL. Five subgroups (TyG index 7.81-8.04, 8.04-8.21, 8.21-8.37, 8.37-8.52, and 8.52-8.68) did not show significant effect on LTL; while there was a significantly shorter LTL for participants with the TyG index > 8.68, supporting a threshold effect of TyG index on LTL.ConclusionsThe results suggested that higher TyG index (> 8.68) was closely related to shorter LTL and the TyG index was better associated with LTL than HOMA-IR.

0059 Does Discrimination Moderate the Relationship between Insomnia and Telomere Length in Older Adults from Three Racial/Ethnic Groups?

Abstract Introduction Both insomnia and discrimination have been associated with adverse physical and mental health outcomes. Evidence suggests that discrimination may moderate the effects of sleep on telomeres, DNA sequences at the end of chromosomes that protect them from degradation. The purpose of this study was to determine the relationship between insomnia and telomere length among older non-latinx white, black, and latinx individuals and whether discrimination moderated this relationship differently based on race or ethnicity. Methods This study is a secondary analysis from the Health and Retirement Study, a longitudinal project sponsored by the National Institute on Aging. Our analysis consisted of 3,205 US participants who provided information on sleep problems as well as salivary samples from which telomere data were assayed. We computed a linear regression to examine the relationship between insomnia symptoms and telomere length in each racial/ethnic group, including interaction terms to assess moderating effects of discrimination. Results Insomnia symptoms were associated with shortened telomere length among non-latinx white participants (β -0.046, p=0.015, [-0.06, -0.01]). Discrimination had a moderating effect between insomnia symptoms and telomere length among black participants (β -0.28, p=0.045, [-0.33, -0.00]). Analyses remained significant after adjusting for age, medical co-morbidities, smoking status, and a history of depression. Conclusion Our results suggest that symptoms of insomnia may contribute to telomere erosion, with potentially adverse effects on genomic integrity. For black individuals, those who experienced discrimination were at greater risk of telomere damage associated with insomnia. Support (If Any) Funding has been made available by the NIH, granted to UCSF School of Nursing Biobehavioral Research Training Program in Symptom Science (NIH: T32 NRO16920).

Association of Dietary Magnesium Intake With Leukocyte Telomere Length in United States Middle-Aged and Elderly Adults.

AimMagnesium supplementation may extend the life span; however, the biological mechanism is still unknown. Leukocyte telomere length (LTL) is a marker of cell aging and biological health in humans. Data concerning whether magnesium supplementation can maintain telomere length, thus prolonging life are limited. We aimed to investigate the association between dietary magnesium intake and LTL in United States middle-aged and elderly adults.MethodsA total of 4,039 United States adults aged ≥ 45 years from National Health and Nutrition Examination Survey (1999–2002). Dietary magnesium intake was collected by a trained interviewer using 24-h dietary recall method and LTL was obtained using the quantitative polymerase chain reaction method. Multiple linear regression analysis was performed to evaluate the crude and adjusted association of dietary magnesium intake with LTL.ResultsThe overall mean (SD) of LTL was 5.6 (0.6) kp. After adjusting potential confounders, every 1 mg increase in log-transformed dietary magnesium intake was associated with 0.20 kp (95% confidence intervals: 0.05–0.34) longer LTL. Participants with the highest tertile (≥299 mg) of dietary magnesium intake had statistically significant longer LTL (β = 0.07, P = 0.038) compared with the lowest tertile (<198 mg), with significant linear trends across tertiles. Moreover, the association between dietary magnesium intake and LTL was significantly stronger in participants with higher levels of education (≥high school compared with < high school, P for interaction = 0.002). E-value analysis suggested robustness to unmeasured confounding.ConclusionOur findings showed that increased dietary magnesium intake was associated with longer LTL, which suggested that magnesium was conducive to a longer life expectancy.

Effect of Physical Activity, Smoking, and Sleep on Telomere Length: A Systematic Review of Observational and Intervention Studies.

Aging is a risk factor for several pathologies, restricting one’s health span, and promoting chronic diseases (e.g., cardiovascular and neurodegenerative diseases), as well as cancer. Telomeres are regions of repetitive DNA located at chromosomal ends. Telomere length has been inversely associated with chronological age and has been considered, for a long time, a good biomarker of aging. Several lifestyle factors have been linked with telomere shortening or maintenance. However, the consistency of results is hampered by some methodological issues, including study design, sample size, measurement approaches, and population characteristics, among others. Therefore, we aimed to systematically review the current literature on the effects of three relevant lifestyle factors on telomere length in human adults: physical activity, smoking, and sleep. We conducted a qualitative systematic review of observational and intervention studies using the Preferred Reporting Item for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The systematic literature search covered articles published in MEDLINE and EMBASE databases (from 2010 to 2020). A total of 1400 studies were identified; 83 were included after quality control. Although fewer sedentary activities, optimal sleep habits, and non- or ex-smoker status have been associated with less telomere shortening, several methodological issues were detected, including the need for more targeted interventions and standardized protocols to better understand how physical activity and sleep can impact telomere length and aging. We discuss the main findings and current limitations to gain more insights into the influence of these lifestyle factors on the healthy aging process.

Effects of 6-Month Supplementation with Multi-Component Herbal Supplement PhytodynamicTM on Mitochondrial Function, Telomere Length, and Chronic Inflammation in Adults Aged 65 Years and Older: A Pilot Trial

Herbal supplements are often used by elderly populations in aim to manage age-related traits; yet, most have shown limited benefits, keeping a quest for safe and effective longevity-promoting mixtures open. The main aim of the present study was to evaluate the effects of 6-month supplementation with multi-component herbal mixture P-DNA for telomere length, biomarkers of mitochondrial function and chronic inflammation, and self-reported adverse events in men and women aged 65 years and older. Fourteen older adults (74.6 ± 6.3 years, height 164.1 ± 13.0 cm, weight 69.9 ± 13.4 kg; 11 women) signed an informed consent to voluntarily participate in this randomized controlled parallel-group pilot trial. All participants were allocated in a double-blind design to receive either P-DNA or placebo (inulin) during a 6-month intervention period, with the outcomes assessed at baseline and 6-month follow-up were biomarkers of mitochondrial function (fibroblast growth factor 21, growth-differentiation factor 15), inflammation (high-sensitive C-reactive protein, interleukin-6, and amyloid A), and telomere length. Two-way analysis of variance with repeated measures was used to establish if any significant differences existed between patients’ responses over time of intervention; for data with nonhomogenous variances the Kruskal– Wallis test was employed for the between group comparisons and Freidman’s test for the within group comparisons. Growth-differentiation factor 15 significantly dropped after PhytoDyNAmicTM intervention as compared to the baseline levels (P = 0.02), while serum interleukin-6 significantly increased from baseline levels in both groups at 6-month follow-up (P &lt; 0.05). No participant reported major side effects of any intervention. PhytoDyNAmicTM appears to favorably affect mitochondrial function in adults aged 65 years and older; additional studies are needed to corroborate these promising findings.

Gut-Derived Endotoxin and Telomere Length Attrition in Adults with and without Type 2 Diabetes.

Premature aging, as denoted by a reduced telomere length (TL), has been observed in several chronic inflammatory diseases, such as obesity and type 2 diabetes mellitus (T2DM). However, no study to date has addressed the potential inflammatory influence of the gut-derived Gram-negative bacterial fragments lipopolysaccharide, also referred to as endotoxin, and its influence on TL in low-grade inflammatory states such as type 2 diabetes mellitus (T2DM). The current study therefore investigated the influence of endotoxin and inflammatory factors on telomere length (TL) in adults with (T2DM: n = 387) and without (non-diabetic (ND) controls: n = 417) obesity and T2DM. Anthropometric characteristics were taken, and fasted blood samples were used to measure biomarkers, TL, and endotoxin. The findings from this study highlighted across all participants that circulating endotoxin (r = −0.17, p = 0.01) was inversely associated with TL, noting that endotoxin and triglycerides predicted 18% of the variance perceived in TL (p < 0.001). Further stratification of the participants according to T2DM status and sex highlighted that endotoxin significantly predicted 19% of the variance denoted in TL among male T2DM participants (p = 0.007), where TL was notably influenced. The influence on TL was not observed to be impacted by anti-T2DM medications, statins, or anti-hypertensive therapies. Taken together, these results show that TL attrition was inversely associated with circulating endotoxin levels independent of the presence of T2DM and other cardiometabolic factors, suggesting that low-grade chronic inflammation may trigger premature biological aging. The findings further highlight the clinical relevance of mitigating the levels of circulating endotoxin (e.g., manipulation of gut microbiome) not only for the prevention of chronic diseases but also to promote healthy aging.