Telomere length is a biomarker of cumulative oxidative stress, biologic age, and an independent predictor of survival and therapeutic treatment requirement associated with smoking behavior

Association of lymphocyte count and serum albumin concentration with telomere length in Chinese sanitation workers

OBJECTIVE

This study aimed to examine the association between inflammation-related indicators (IRIs) and telomere length (TL) in Chinese sanitation workers.

METHODS

This study adopted a case-control design, conducted from January to December 2022 in Shenzhen, a city in eastern China. A total of 80 sanitation workers, as well as 80 matched controls, were randomly recruited from the Luohu district of Shenzhen city in China. Their blood samples were collected and analyzed for the IRIs and TL in the Medical Laboratory of Shenzhen Prevention and Treatment Center for Occupational Diseases. The relationship between IRIs and TL was analyzed using multivariate linear regression, and their dose-response relationship was explored using restricted cubic spline analysis.

RESULTS

The systemic inflammatory index (SII), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR) were significantly elevated in the sanitation workers in comparison to the controls. Moreover, the lymphocyte count (LYM), serum albumin concentration (ALB), and TL were found to be lower in the sanitation workers compared to the controls (P < 0.05). After adjusting for potential confounding variables, LYM was negatively correlated with TL in the sanitation workers (β = -0.31, 95% CI: -0.57, -0.05), whereas no correlation was observed in the controls. Furthermore, ALB demonstrated a non-linear relationship with TL in sanitation workers.

CONCLUSION

We found higher novel inflammatory markers (SII, PLR, and NLR) in the sanitation workers, and identified a correlation between LYM and ALB with shortened TL in them, providing new evidence for the effect of elevated inflammation on accelerated aging in Chinese sanitation workers.

The association of telomere length with body mass index and immunological factors differs according to physical activity practice among children and adolescents

BACKGROUND

This study aims to verify the relationship between screen and sleep time, body mass index (BMI) and immunological factors with telomere length according to leisure-time physical activity (PA) in children and adolescents.

METHODS

A cross-sectional study involving a sample of 476 schoolchildren of both sexes, aged seven to 17 years, from a community in southern Brazil. Behavioral variables (PA, sleep time, and screen time) were self-reported using a questionnaire. PA was classified as inactive and any PA (doing some physical activity). The associations of screen time, sleep time, BMI, and immunologic factors with telomere length were tested using multiple linear regression models, with the sample divided according to the schoolchildren's leisure-time physical activity practices.

RESULTS

An inverse association between BMI and telomere length (β: -0.239; 95% CI: -0.468; -0.010) and a direct association of leukocytes (β: 0.151; 95% CI: 0.029; 0.278) and neutrophils (β: 0.131; 95% CI: 0.008; 0.254) with telomeres were found in the inactive students. No association was found between screen time and sleep time and telomeres. No association was found among students who engaged in any PA.

CONCLUSION

The associations between telomeres, BMI, and immunologic factors were found only in inactive students. These results suggest that the association between BMI and immunological factors and telomere length may be influenced by physical activity.

The brain-skin axis in vitiligo

Vitiligo is an acquired autoimmune skin disease characterized by patchy depigmentation of the skin, often accompanied by white hair. The aetiology of vitiligo is complex and difficult to cure, and its disfiguring appearance significantly impacts patients' mental and physical health. Psychological stress is a major factor in inducing and exacerbating vitiligo, as well as affecting its treatment efficacy, though the specific mechanisms remain unclear. Increasing research on the brain-skin axis in skin immunity suggests that psychological stress can influence local skin immunity through this axis, which may play a crucial role in the pathogenesis of vitiligo. This review focuses on the role of brain-skin axis in the pathogenesis of vitiligo, and explores the possible mechanism of brain-skin axis mediating the pathogenesis of vitiligo from the aspects of sympathetic nervous system, hypothalamic-pituitary-adrenal (HPA) axis and hormones and neuropeptides, aiming to provide the necessary theoretical basis for psychological intervention in the prevention and treatment of vitiligo.

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.

Exploring the interplay between stress mediators and skin microbiota in shaping age-related hallmarks: A review

Psychological stress is a major contributing factor to several health problems (e.g., depression, cardiovascular disease). Around 35 % of the world's population suffers from it, including younger generations. Physiologically, stress manifests through neuroendocrine pathways (Hypothalamic-Pituitary-Adrenal (HPA) axis and Sympathetic-Adrenal-Medullary (SAM) system) which culminate in the production of stress mediators like cortisol, epinephrine and norepinephrine. Stress and its mediators have been associated to body aging, through molecular mechanisms such as telomere attrition, mitochondrial dysfunction, cellular senescence, chronic inflammation, and dysbiosis, among others. Regarding its impact in the skin, stress impacts its structural integrity and physiological function. Despite this review focusing on several hallmarks of aging, emphasis was placed on skin microbiota dysbiosis. In this line, several studies, comprising different age groups, demographic contexts and body sites, have reported skin microbiota alterations associated with aging, and some effects of stress mediators on skin microbiota have also been reviewed in this paper. From a different perspective, since it is not a "traditional" stress mediator, oxytocin, a cortisol antagonist, has been related to glucorticoids inhibition and to display positive effects on cellular aging. This hormone dysregulation has been associated to psychological issues such as depression, whereas its upregulation has been linked to positive social interaction.

Association between telomere length and erectile dysfunction: a cross-sectional study

Background

Leukocyte telomere length (LTL) serves as a significant biomarker of aging. Erectile dysfunction (ED) is a commonly observed condition among middle-aged and older men. The objective of this study is to explore the potential association between LTL and ED.

Methods

We utilized data from the National Health and Nutrition Examination Survey (NHANES) to examine the association between LTL and ED. Weighted multivariate regression analyses were performed as the primary statistical method. Subgroup analyses were conducted to investigate specific population subsets, and restricted cubic spline (RCS) analyses were employed to assess the non-linear relationship between LTL and ED.

Results

The results of weighted multivariate regression analyses revealed a negative correlation between LTL and the risk of ED. Individuals with ED exhibited shorter LTL compared to those without ED. For each unit increase in LTL, there was a 54% reduction in the risk of ED (odds ratios[OR] 0.46, 95% confidence intervals[CI] 0.25-0.85). When LTL was considered as a categorical variable, the group with the longest LTL (Q5) had a 44% lower risk of ED compared to the group with the shortest LTL(Q1) (OR 0.56, 95% CI 0.39-0.81). A non-linear relationship was observed between TL and ED. Various sensitivity analyses were conducted to validate the stability of the results, and consistent findings were obtained.

Conclusion

The negative association between leukocyte LTL and ED suggests that delaying the shortening of LTL may decrease the risk of ED.

Methamphetamine use shortens telomere length in male adults and rats

BACKGROUND

Methamphetamine (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.

METHODS

We 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.

RESULTS

At 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.

CONCLUSION

MA 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.

Pharmacological potentials of lycopene against aging and aging-related disorders: A review

Aging and aging-related chronic disorders are one of the principal causes of death worldwide. The prevalence of these disorders is increasing gradually and globally. Considering this unwavering acceleration of the global burden, seeking alternatives to traditional medication to prevent the risk of aging disorders is needed. Among them, lycopene, a carotenoid, is abundant in many fruits and vegetables, including tomatoes, grapefruits, and watermelons, and it has a unique chemical structure to be a potent antioxidant compound. This nutraceutical also possesses several anti-aging actions, including combating aging biomarkers and ameliorating several chronic disorders. However, no systematic evaluation has yet been carried out that can comprehensively elucidate the effectiveness of lycopene in halting the course of aging and the emergence of chronic diseases linked to aging. This review, therefore, incorporates previous pre-clinical, clinical, and epidemiological studies on lycopene to understand its potency in treating aging disorders and its role as a mimic of caloric restriction. Lycopene-rich foods are found to prevent or attenuate aging disorders in various research. Based on the evidence, this review suggests the clinical application of lycopene to improve human health and alleviate the prevalence of aging and aging disorders.

Determinants of oxidative stress among indigenous populations in Northern Laos: Trace element exposures and dietary patterns

OBJECTIVES

To investigate determinants of oxidative stress in an indigenous population, we examined associations of trace element exposures and dietary patterns with three oxidative stress-related biomarkers among indigenous populations in Northern Laos.

METHODS

This cross-sectional study included 341 adults from three villages with different levels of modernization. We used three oxidative stress-related biomarkers: urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and 8-isoprostane concentrations, which were measured using liquid chromatography-tandem mass spectrometry, and blood telomere lengths, which were measured using a quantitative polymerase chain reaction method. We used multilevel analysis to examine associations of urinary arsenic, cadmium, and selenium concentrations, their interaction terms, and wild-plant-food scores (principal component scores calculated from food consumption frequencies) with oxidative stress-related biomarkers.

RESULTS

Urinary arsenic and cadmium concentrations were positively associated with urinary 8-isoprostane concentrations. Urinary selenium concentrations were positively associated with urinary 8-OHdG concentrations. Interaction terms ([arsenic or cadmium] × selenium) showed negative associations with urinary 8-OHdG and 8-isoprostane concentrations, respectively. Urinary cadmium concentrations were negatively associated with telomere lengths. Wild-plant-food scores did not exhibit associations with oxidative stress-related biomarkers.

CONCLUSION

Our findings imply that exposure to arsenic and cadmium is associated with greater oxidative lipid damage, whereas selenium may attenuate arsenic-induced oxidative DNA damage and cadmium-induced oxidative lipid damage. Cadmium exposure may accelerate telomere attrition. Trace element exposure may be a determinant of oxidative stress among indigenous populations in Northern Laos.

Impact of modernization on oxidative stress among indigenous populations in northern Laos

OBJECTIVES

To explore the impact of modernization on oxidative stress during a momentous health transition process, we investigated differences in oxidative stress among the indigenous populations of villages in northern Laos with different levels of modernization.

METHODS

We conducted a cross-sectional study of 380 adults in three villages with different levels of modernization. Three biomarkers related to oxidative stress were measured: urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and 8-isoprostane concentrations (both measured by liquid chromatography-tandem mass spectrometry), and blood telomere length (measured with qPCR). We examined associations between village-level modernization and oxidative stress-related biomarkers in a multilevel analysis including a random effect and covariates.

RESULTS

The geometric means of urinary 8-OHdG and 8-isoprostane concentrations were 2.92 and 0.700 μg/g creatinine, respectively, in our study population. Higher urinary 8-OHdG concentrations and shorter telomeres were observed in participants from the more modernized villages, whereas urinary 8-isoprostane concentrations did not differ significantly among villages.

CONCLUSIONS

Our findings imply that modernization-induced changes in lifestyle may increase oxidative DNA damage. Baseline levels of oxidative lipid damage are expected to be high in the indigenous populations of northern Laos. Assessments of oxidative stress may provide valuable insights into the mechanisms of health transition in specific populations.

Functional association between telomeres, oxidation and mitochondria

Prior research has substantiated the vital role of telomeres in human fertility. Telomeres are prerequisites for maintaining the integrity of chromosomes by preventing the loss of genetic material following replication events. Little is known about the association between sperm telomere length and mitochondrial capacity involving its structure and functions. Mitochondria are structurally and functionally distinct organelles that are located on the spermatozoon's midpiece. Mitochondria produce adenosine triphosphate (ATP) through oxidative phosphorylation (OXPHOS), which is necessary for sperm motility and generate reactive oxygen species (ROS). While a moderate concentration of ROS is critical for egg-sperm fusion, and fertilization, excessive ROS generation is primarily related to telomere shortening, sperm DNA fragmentation, and alterations in the methylation pattern leading to male infertility. This review aims to highlight the functional connection between mitochondria biogenesis and telomere length in male infertility, as mitochondrial lesions have a damaging impact on telomere length, leading both to telomere lengthening and reprogramming of mitochondrial biosynthesis. Furthermore, it aims to shed light on how both inositol and antioxidants can positively affect male fertility.

Longitudinal Association of Telomere Dynamics with Obesity and Metabolic Disorders in Young Children

In adults, short leukocyte telomere length (LTL) is associated with metabolic disorders, such as obesity and diabetes mellitus type 2. These associations could stem from early life interactions between LTL and metabolic disorders. To test this hypothesis, we explored the associations between LTL and metabolic parameters as well as their evolution over time in children with or without obesity at baseline. Seventy-three (n = 73) children attending our Outpatient Clinic for the Prevention and Management of Overweight and Obesity in Childhood and Adolescence, aged 2-10 years (mean ± SD: 7.6 ± 2.0 years), were followed for 2 to 4 years. Anthropometric, clinical, and biological (including LTL by Southern blot) measurements were performed annually. Baseline LTL correlated negatively with BMI (p = 0.02), fat percentage (p = 0.01), and blood glucose (p = 0.0007). These associations persisted after adjustments for age and sex. No associations were found between LTL attrition during the follow-up period and any of the metabolic parameters. In young children, obesity and metabolic disturbances were associated with shorter telomeres but were not associated with more pronounced LTL attrition. These results suggest that short telomeres contribute to the development of obesity and metabolic disorders very early in life, which can have a major impact on health.

Mindfulness Meditation Interventions for Long COVID: Biobehavioral Gene Expression and Neuroimmune Functioning

Some individuals infected with SARS CoV-2 have developed Post-Acute Sequelae of SARS CoV-2 infection (PASC) or what has been referred to as Long COVID. Efforts are underway to find effective treatment strategies for those with Long COVID. One possible approach involves alternative medical interventions, which have been widely used to treat and manage symptoms of a variety of medical problems including post-viral infections. Meditation has been found to reduce fatigue and unrefreshing sleep, and for those with post-viral infections, it has enhanced immunity, and reduced inflammatory-driven pathogenesis. Our article summarizes the literature on what is known about mindfulness meditation interventions, and reviews evidence on how it may apply to those with Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Evidence is reviewed suggesting effective and sustainable outcomes may be achieved for symptomatology and underlying pathology of post-viral fatigue (PASC and ME/CFS).

Shorter periconception maternal telomere length and the risk of congenital cardiac outflow defects in the offspring

BACKGROUND

Congenital cardiac outflow defects (COD) are the largest group of congenital heart defects, with ventricular septal defect (VSD) as the most prevalent phenotype. Increased maternal age, excessive oxidative stress and inflammation are involved in the pathophysiology of COD and enhance telomere length (TL) shortening. We investigated the association between periconception maternal TL and the risk of having a child with COD.

METHODS

From a multicentre case-control trial, 306 case mothers of a child with COD and 424 control mothers of a child without a congenital malformation were selected. Relative TL was measured by qPCR. Multivariable logistic regression was used to compute crude and adjusted odds ratios, per standard deviation decrease, between maternal T/S ratio and COD and VSD risk. Adjustments were made for maternal age. Additional adjustments were made in a second model.

RESULTS

Shorter maternal relative TL was significantly associated with an OR of 1.29 (95% CI 1.04-1.61), p = .02, for the risk of VSD in offspring, which remained significant after an adjustment for maternal age (adjOR 1.25(95% CI 1.01-1.55), p = .04). No association between maternal TL and the risk of overall COD in offspring was observed.

CONCLUSION

Shorter maternal relative TL is associated with an approximately 1.3-OR for the risk, per SD in relative TL shortening, of VSD in the offspring. These findings need further confirmation in other studies on the predictive value of maternal TL.

Clinical significance of germline telomere length and associated genetic factors in patients with neuroblastoma

Studies investigating the relationship between germline telomere length and the clinical characteristics of tumors are very limited. This study evaluated the relationship between germline telomere length and the clinical characteristics of neuroblastoma. In addition, a genome-wide association study (GWAS) was performed to investigate the genetic factors associated with germline telomere length. The germline telomere length of peripheral blood mononuclear cells from 186 patients with neuroblastoma was measured by quantitative polymerase chain reaction. The association between germline telomere length and clinical characteristics, including long-term survival, was investigated. For the GWAS, genotyping was performed with a high-density bead chip (Illumina, San Diego, CA, USA). After strict quality-control checks of the samples, an association analysis was conducted. The result showed that longer germline telomeres were significantly associated with longer event-free survival (P = 0.032). To identify significantly assocated genetic markers for germline telomere length, genome wide association analysis was performed. As a result, several single nucleotide polymorphisms located in HIVEP3, LRRTM4, ADGRV1, RAB30, and CHRNA4 genes were discovered. During gene-based analysis (VEGAS2 tool), the CNTN4 gene had the most significant association with germline telomere length (P = 1.0E−06). During gene ontology analysis, susceptible genes associated with germline telomere length were mainly distributed in neurite morphogenesis and neuron development. A longer germline telomere length is associated with favorable prognostic factors at diagnosis and eventually better event-free survival in patients with neuroblastoma. In addition, the GWAS demonstrated that genetic markers and genes related to germline telomere length are associated with neurite morphogenesis and neuron development. Further research with larger cohorts of patients and functional investigations are needed.

Whole-cell biotransformation for large scale production of carcinine in Escherichia coli

Carcinine is a natural imidazole-containing peptide derivative. It is widely used in the cosmetics industry as anti-aging supplement with antioxidant, anti-glycation and glycation reversal functions, and it also has a notable pharmacological effect as anti-tumor drug and in protection against retinopathy. However, a technological method for synthesis and production of carcinine has not been established. In this study, a whole-cell transformation system converting β-alanine and histamine to carcinine by the enzymes Ebony and phosphopantetheine transferase (Sfp) has been developed. The results revealed that the catalytic efficiency of the strain containing the fusion protein of Ebony and Sfp (Sfp-glycine-serine-glycine-Ebony, SGE) in Escherichia coli W3110 (WSGE strain) is significantly higher (7.45 mM) than the combinatorial strain of pET28a-ebony and pACYCDuet-sfp in E. coli BL21(DE3) (BSE strain) (2.17 mM). Under the optimal reaction conditions (25 ℃, pH 7.0, 12.5 g/L wet cells, 20 mM β-alanine and 40 mM histamine), the carcinine can be quickly synthesized within 24 h up to a concentration of 22.63 mM. To achieve a continuous and efficient conversion of the precursors, a batch-feeding catalysis was designed. With this system, β-alanine (40 mM) and histamine (40 mM) could be completely transformed to carcinine (40.34 mM) in 36 h with a productivity of 0.204 g/L h reaching a titer of 7.34 g/L. Hence, the batch-feeding whole-cell biocatalysis is a promising technology for the high yield production of carcinine which can promote the industrial production of carcinine.

Obesity Accelerates Leukocyte Telomere Length Shortening in Apparently Healthy Adults: A Meta-Analysis

Background

Shorter telomere length is associated with numerous comorbidities. Several studies have investigated the role of obesity in telomere shortening. In the current systematic review and meta-analysis, we summarized the results of studies that evaluated the association between obesity and telomere length.

Methods

A systematic search from Scopus, PubMed, Embase, and ProQuest electronic databases up to 19 March 2021 without language restriction was performed and after data extraction and screening, 19 manuscripts were eligible to be included in the final meta-synthesis.

Results

The highest category of telomere length was associated with an approximate 0.75 kg/m2 reduction in body mass index (BMI; WMD = -0.75 kg/m2; CI = -1.19, -0.31; p < 0.001; I 2 = 99.4%). Moreover, overweight/obese individuals had 0.036 kbp shorter telomere length compared with non-overweight/obese adults (WMD = -0.036; CI = -0.05, -0.02; p = 0.030; I 2 = 100%). According to the results of subgroupings, continent, age, and sample size could be possible sources of heterogeneity.

Conclusion

From the results, it was clear that obesity was associated with shorter telomere length. Because of the observational design of included studies, the causality inference of results should be done with caution; thus, further longitudinal studies are warranted for better inference of causal association.

Shortened Infant Telomere Length Is Associated with Attention Deficit/Hyperactivity Disorder Symptoms in Children at Age Two Years: A Birth Cohort Study

Environmental factors can accelerate telomere length (TL) attrition. Shortened TL is linked to attention deficit/hyperactivity disorder (ADHD) symptoms in school-aged children. The onset of ADHD occurs as early as preschool-age, but the TL-ADHD association in younger children is unknown. We investigated associations between infant TL and ADHD symptoms in children and assessed environmental factors as potential confounders and/or mediators of this association. Relative TL was measured by quantitative polymerase chain reaction in cord and 12-month blood in the birth cohort study, the Barwon Infant Study. Early life environmental factors collected antenatally to two years were used to measure confounding. ADHD symptoms at age two years were evaluated by the Child Behavior Checklist Attention Problems (AP) and the Attention Deficit/Hyperactivity Problems (ADHP). Associations between early life environmental factors on TL or ADHD symptoms were assessed using multivariable regression models adjusted for relevant factors. Telomere length at 12 months (TL12), but not at birth, was inversely associated with AP (β = −0.56; 95% CI (−1.13, 0.006); p = 0.05) and ADHP (β = −0.66; 95% CI (−1.11, −0.21); p = 0.004). Infant secondhand smoke exposure at one month was independently associated with shorter TL12 and also higher ADHD symptoms. Further work is needed to elucidate the mechanisms that influence TL attrition and early neurodevelopment.

Association between the Oxidative Balance Score and Telomere Length from the National Health and Nutrition Examination Survey 1999-2002

Purpose. Leukocyte telomere length (LTL) is an important biomarker of aging. The oxidative balance score (OBS) is used to assess the oxidative stress-related exposures of diet and lifestyle. This study is aimed at exploring if the OBS was associated with LTL. Methods. 3220 adults were included in this study from the National Health and Nutrition Examination Survey (NHANES) 1999-2002. LTL was assayed from leukocyte DNA. Twenty dietary and lifestyle factors were selected to score the OBS. Survey-based multivariable linear regression was conducted to assess the association between the OBS and log-transformed LTL. Results. The association between the OBS and log-transformed LTL was positive in females but not males. For females, compared with the lowest OBS category as a reference, the multivariable-adjusted beta estimate (95% confidence interval, CI) for the highest OBS category was 0.0701 (0.0205–0.1197) ( $p$ for $\text{trend}<0.01$ ), and the multivariable-adjusted beta estimate (95% CI) of the continuous OBS was 0.0039 (0.0014–0.0065). There was also the gender difference in the correlations of the dietary OBS and the lifestyle OBS with log-transformed LTL. Conclusion. There was a positive association between the OBS and LTL in females. This result suggested that diet and lifestyle might affect LTL by regulating oxidative balance.

Telomere length and urinary 8-hydroxy-2'-deoxyguanosine and essential trace element concentrations in female Japanese university students

Telomere length is thought to be a biomarker of biological aging. This study examined whether telomere length was associated with urinary concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a biomarker of oxidative stress, and antioxidative trace elements in 73 female Japanese university students (age: 19.2 ± 0.7 years). We quantified 8-OHdG and selenium in urine by liquid chromatography-mass spectrometry and inductively coupled plasma-mass spectrometry, respectively. Telomere length and urinary concentrations of other essential trace elements (molybdenum, cobalt, and chromium) that were previously measured in the same study participants, were used in this study. We used multiple linear regression analysis to examine the associations of telomere length with urinary 8-OHdG and essential trace element concentrations (covariates: urinary cotinine concentration, age, BMI, and drinking status). The geometric means (geometric standard deviation) of 8-OHdG and selenium were 3.4 (1.5) and 31 (1.3) µg/g creatinine, respectively. Telomere length was not associated with urinary 8-OHdG concentration, but was negatively associated with urinary selenium concentration. In conclusion, telomere length was not associated with urinary 8-OHdG concentration in the young women in this study. Longitudinal studies should be conducted to clarify the association between telomere shortening rate and oxidative stress level.

Influence of the Bioactive Diet Components on the Gene Expression Regulation

Diet bioactive components, in the concept of nutrigenetics and nutrigenomics, consist of food constituents, which can transfer information from the external environment and influence gene expression in the cell and thus the function of the whole organism. It is crucial to regard food not only as the source of energy and basic nutriments, crucial for living and organism development, but also as the factor influencing health/disease, biochemical mechanisms, and activation of biochemical pathways. Bioactive components of the diet regulate gene expression through changes in the chromatin structure (including DNA methylation and histone modification), non-coding RNA, activation of transcription factors by signalling cascades, or direct ligand binding to the nuclear receptors. Analysis of interactions between diet components and human genome structure and gene activity is a modern approach that will help to better understand these relations and will allow designing dietary guidances, which can help maintain good health.

Central obesity accelerates leukocyte telomere length (LTL) shortening in apparently healthy adults: A systematic review and meta-analysis

Shorter telomere length is associated with numerous comorbidities; central obesity might trigger leukocyte telomere shortening; in the current meta-analysis we evaluated the association of central obesity with leukocyte telomere length among adults. A systematic search from Scopus, PubMed, Embase and Proquest electronic databases up to May 2021 was done. The final screening, provided five articles to be included in final meta-analysis. Those in the highest category of telomere length had 3.72 cm lower waist circumference (WC) compared with those in the lowest category (WMD=-3.718; CI=-7.180, -0.257 P = 0.035; I² = 95.4%). Also, those in the highest LTL category had 0.02 lower waist to hip ratio (WHR) compared with those in the lowest category, although this association was not significant (WMD: -0.02; CI=-0.04, 0.01; P = 0.19; I²= 90.7%). In quality assessment of included studies, all of the studies had moderate or high quality score and there was no study with poor quality. Higher leukocyte telomere length was accompanied with lower WC among adults. This association was not significant for difference in WHR. Because of the high heterogeneity values and also because of the observational design of included studies, the inference of causality of these associations needs further investigations.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2021.1971155 .

Fruit and Vegetable Intake and Telomere Length in a Random Sample of 5448 U.S. Adults

The relationship between fruit and vegetable intake and telomere length was examined using a cross-sectional design and an NHANES random sample of 5448 U.S. adults. Fruit and vegetable (F&V) consumption was assessed using a 24 h recall, and telomere length, an index of cellular aging, was measured using the quantitative polymerase chain reaction method. Telomere length was linearly related to F&V intake when combined (F = 22.7, p < 0.0001) and also when separated as fruit (F = 7.2, p < 0.0121) or vegetables (F = 15.4, p < 0.0005), after adjusting for covariates. Specifically, telomeres were 27.8 base pairs longer for each 100 g (3.5 ounces) of F&V consumed. Because each additional year of chronological age was associated with telomeres that were 14.9 base pairs shorter, when women and men were analyzed together, results indicated that a 100 g (3.5 oz) per day increment in F&V corresponded with 1.9 years less biological aging. When the 75th percentile of F&V intake was compared to the 25th, the difference was 4.4 years of cellular aging. When separated by sex, fruits and vegetables were both related to telomere length in women, but only vegetable intake was predictive of telomere length in men. In conclusion, evidence based on a random sample of U.S. adults indicates that the more the servings of F&V, the longer telomeres tend to be.

Telomere length determinants in childhood

Telomere length (TL) is a dynamic marker that reflects genetic predispositions together with the environmental conditions of an individual. It is closely related to longevity and a number of pathological conditions. Even though the extent of telomere research in children is limited compared to that of adults, there have been a substantial number of studies providing first insights into child telomere biology and determinants. Recent discoveries revealed evidence that TL is, to a great extent, determined already in childhood and that environmental conditions in adulthood have less impact than first believed. Studies have demonstrated that large inter-individual differences in TL are present among newborns and are determined by diverse factors that influence intrauterine development. The first years of child growth are associated with high cellular turnover, which results in fast shortening of telomeres. The rate of telomere loss becomes stable in early adulthood. In this review article we summarise the existing knowledge on telomere dynamics during the first years of childhood, highlighting the conditions that affect newborn TL. We also warn about the knowledge gaps that should be filled to fully understand the regulation of telomeres, in order to implement them as biomarkers for use in diagnostics or treatment.

Leukocyte telomere length is associated with iron overload in male adults with hereditary hemochromatosis

Background: Hereditary hemochromatosis (HH) is a primary iron overload (IO) condition. Absolute telomere length (ATL) is a marker of cellular aging and DNA damage associated with chronic diseases and mortality.

Aim: To evaluate the relationship between ATL and IO in patients with HH.

Methods: Cross-sectional study including 25 patients with HH: 8 with IO and 17 without IO (ferritin < 300 ng/ml) and 25 healthy controls. Inclusion criteria were: age > 18 years, male sex and HH diagnosis. Patients with diabetes or other endocrine and autoimmune diseases were excluded. ATL was measured by real-time PCR.

Results: HH patients with IO were older (P<0.001) and showed higher ferritin concentration (P<0.001). Patients with HH, disregarding the iron status, showed higher glucose and body mass index (BMI) than controls (both P<0.01). ATL was shorter in patients with IO than controls [with IO: 8 (6–14), without IO: 13 (9–20), and controls: 19 (15–25) kilobase pairs, P<0.01]; with a linear trend within groups (P for trend <0.01). Differences in ATL remained statistically significant after adjusting by age, BMI and glucose (P<0.05).

Discussion: Patients with IO featured shorter ATL while patients without IO showed only mild alterations vs. controls. Screening for IO is encouraged to prevent iron-associated cellular damage and early telomere attrition.

The joint effects of frailty and telomere length for predicting mortality in older adults: the National Health and Nutrition Examination Survey 1999-2002

BACKGROUND

Frailty and short telomere length, which address different aspects of biological aging, are separately associated with mortality in older adults.

AIMS

To evaluate whether the combination of these two biomarkers would be a better predictor of mortality than either alone.

METHODS

This present study included participants 60 years of age or older from the National Health and Nutrition Examination Survey in the 1999-2002 phase. The frailty phenotype was identified based on the Fried definition. Telomere length relative to standard reference DNA (T/S ratio) was assessed using quantitative polymerase chain reaction (PCR). Cox proportional hazards regression models were used to estimate the individual and combined effects of frailty phenotype and telomere length on all-cause and cardiovascular mortality.

RESULTS

Compared with participants with neither impairment, the mortality risks increased slightly among participants with short telomere length only (hazard ratio [HR] 1.19, 95% confidence interval [CI]: 1.00-1.42) or pre-frailty only (HR 2.16, 95% CI 1.80-2.60) and gradually elevated approximately 3 folds with both short telomere length and pre-frailty (HR 2.23, 95% CI 1.81-2.74) or frailty (HR 3.57, 95% CI 2.56-4.98). Moreover, participants with both short telomere length and frailty had the highest increased all-cause mortality (HR 5.16, 95% CI 3.38-7.85) and cardiovascular mortality (HR 4.67, 95% CI 2.02-10.82).

DISCUSSION AND CONCLUSIONS

The combined predictor had more capability of predicting mortality, which suggested that integrating both molecular biomarkers and physiological functional parameters would be a more informative measure of biological aging.

Mediterranean Diet and Telomere Length: A Systematic Review and Meta-Analysis

Accelerated telomere shortening has been associated with several age-related diseases and/or decreased lifespan in humans. The Mediterranean diet (MedDiet) is considered to be 1 of the most recognized diets for disease prevention and healthy aging, partially due to its demonstrated anti-inflammatory and antioxidative properties which may impact on telomere length (TL). The aim of this meta-analysis was to determine the associations between MedDiet adherence and TL maintenance. MEDLINE-PubMed and Cochrane databases were searched up to December 2018 for studies evaluating the association between MedDiet adherence and TL in blood cells. Two reviewers, working independently, screened all titles and abstracts to identify studies that met the inclusion criteria [cross-sectional, case-control, and prospective cohort studies and randomized clinical trials (RCTs) published in English and excluded nonoriginal articles]. Data were pooled by the generic inverse variance method using the random effects model and expressed as standardized mean difference (SMD). Heterogeneity was identified using the Cochran Q test and quantified by the I2 statistic. A total of 8 original cross-sectional studies were included for the quantitative meta-analysis, comprising a total of 13,733 participants from 5 countries. A positive association between adherence to the MedDiet and TL was observed in all meta-analyses, with the exception of those conducted only in men: SMD (95% CI) of 0.130 (0.029; 0.231) for all subjects, 0.078 (0.005; 0.152) for women, and 0.095 (-0.005; 0.195) for men. Only 1 prospective cohort study and 1 RCT were identified, therefore, we could not undertake a meta-analysis for these study designs. The present meta-analysis of cross-sectional studies demonstrates that higher MedDiet adherence is associated with longer TL. At the same time, larger and high-quality prospective studies and clinical trials are warranted to confirm this association.

Dendropanax Morbifera Extract-Mediated ZnO Nanoparticles Loaded with Indole-3-Carbinol for Enhancement of Anticancer Efficacy in the A549 Human Lung Carcinoma Cell Line

Dendropanax morbifera is a versatile plant that has been used as a herbal medicine due to its various useful medicinal effects. To protect its active component from biological stress and increase its drug efficacy as well as drug bioavailability, nanoemulsion was prepared. Dendropanax morbifera zinc oxide nanoparticles (DM-ZnO NPs) were synthesized using the plant extract via the co-precipitation method and loaded with active indole-3-carbinol for nanoemulsion formulation using the ultrasonication process. Field emission transmission electron microscope revealed the flower shape of the Dendropanax morbifera indole-3-carbinol zinc oxide nanoemulsion (DM-ZnO-I3C-NE). In contrast, DM-ZnO NPs showed a spheroid shape that coincides agreeably with field emission electron scanning microscope. The hydrodynamic sizes by dynamic light scattering are about 65 ± 3 nm and 239.6 ± 6 nm and the crystallite sizes from X-ray diffraction are 11.52 nm and 16.07 nm for DM-ZnO NPs and DM-ZnO-I3C-NE, respectively. In vitro analysis revealed the cytotoxicity of DM-ZnO-I3C-NE against a human lung cancer cell line (A549) at 12.5 µg/mL as well as reactive oxygen species (ROS) production. The DM-ZnO-I3C-NE-induced ROS generation level was higher than that of DM-ZnO NPs and free indole-3-carbinol. The synergistic effect of DM-ZnO and indole-3-carbinol indicates DM-ZnO-I3C-NE as a potential candidate for future lung cancer drug and could be scope for functional food.

Clark C, Celka R. A Review of Exercise as Medicine in Cardiovascular Disease: Pathology and Mechanism

BACKGROUND

Physical inactivity and resultant lower energy expenditure contribute unequivocally to cardiovascular diseases, such as coronary artery disease and stroke, which are considered major causes of disability and mortality worldwide.

AIM

The aim of the study was to investigate the influence of physical activity (PA) and exercise on different aspects of health - genetics, endothelium function, blood pressure, lipid concentrations, glucose intolerance, thrombosis, and self - satisfaction. Materials and.

METHODS

In this article, we conducted a narrative review of the influence PA and exercise have on the cardiovascular system, risk factors of cardiovascular diseases, searching the online databases; Web of Science, PubMed and Google Scholar, and, subsequently, discuss possible mechanisms of this action.

RESULTS AND DISCUSSION

Based on our narrative review of literature, discussed the effects of PA on telomere length, nitric oxide synthesis, thrombosis risk, blood pressure, serum glucose, cholesterol and triglycerides levels, and indicated possible mechanisms by which physical training may lead to improvement in chronic cardiovascular diseases.

CONCLUSION

PA is effective for the improvement of exercise tolerance, lipid concentrations, blood pressure, it may also reduce the serum glucose level and risk of thrombosis, thus should be advocated concomitant to, or in some cases instead of, traditional drug-therapy.

Early life tobacco exposure and children's telomere length: The HELIX project

Telomere length and mitochondrial DNA content are considered biomarkers of cellular aging, oxidative stress, and inflammation, but there is almost no information on their association with tobacco smoke exposure in fetal and early life. The aim of this study was to assess whether prenatal and childhood tobacco exposure were associated with leukocyte telomere length (LTL) and mitochondrial DNA (mtDNA) content in children. As part of a multi-centre European birth cohort study HELIX (Human Early-Life Exposome) (n = 1396) we assessed maternal smoking status during pregnancy through questionnaires, and through urinary cotinine levels that were then used to classify women as not exposed to smoking (<10 µg/L), exposed to secondhand smoke (SHS) (10-50 µg/L) and active smokers (>50 µg/L). When the children were around 8 years of age (range: 5.4-12.0 years), childhood SHS tobacco smoke exposure was assessed through an extensive questionnaire and through measurements of urinary cotinine (<3.03 µg/L non-detected, >3.03 µg/L detected). Leukocyte mtDNA content and LTL were measured in the children at 8 years employing real time polymerase chain reaction (qPCR). Effect estimates were calculated using multivariate linear regression models for prenatal and childhood exposures adjusted for potential confounders. Maternal cotinine levels indicative of SHS exposure during pregnancy were associated with a decrease of 3.90% in LTL in children (95% CI: -6.68, -0.91), compared with non-smoking, whereas the association for maternal cotinine levels indicative of active smoking did not reach statistical significance (-3.24%; 95% CI: -6.59, 0.21). Childhood SHS tobacco exposure was not associated with LTL in children. Global SHS exposure during childhood was associated with an increase of 3.51% (95% CI: 0.78, 6.27) in mtDNA content. Our findings suggest that tobacco smoke exposure during pregnancy, even at SHS levels, may accelerate telomere shortening in children and thus induce biological aging from an early age.

Walking and biologic ageing: Evidence based on NHANES telomere data

The length of telomeres is an objective measure of biologic ageing. This study evaluated the extent minutes of walking per week are associated with leukocyte telomere length (LTL) in a random sample of 5,823 U.S. adults. The investigation was cross-sectional and data were obtained from the National Health and Nutrition Examination Survey (NHANES). LTL was measured by the quantitative polymerase chain reaction method. Walking minutes was calculated from walking frequency and duration measures. Results showed that for each year of chronological age, telomeres were 15.6 base pairs shorter (P < 0.0001). With walking minutes and LTL treated as continuous variables, the relationship was quadratic, not linear (F = 11.2, P = 0.0023). With walking time divided into three categories, adults who performed ≥ 150 minutes of walking per week had longer telomeres than those who did no regular walking, and those who did some, but less than the recommendation (F = 5.0, P = 0.0137). Regular walkers were estimated to have a biologic ageing advantage associated with 6.5-7.6 years less biologic ageing compared to non-walkers, after adjusting for covariates. Additional investigations designed to study causality and the mechanisms associated with the walking and LTL relationship are needed.

Telomere length correlates with subtelomeric DNA methylation in long-term mindfulness practitioners

Mindfulness and meditation techniques have proven successful for the reduction of stress and improvement in general health. In addition, meditation is linked to longevity and longer telomere length, a proposed biomarker of human aging. Interestingly, DNA methylation changes have been described at specific subtelomeric regions in long-term meditators compared to controls. However, the molecular basis underlying these beneficial effects of meditation on human health still remains unclear. Here we show that DNA methylation levels, measured by the Infinium HumanMethylation450 BeadChip (Illumina) array, at specific subtelomeric regions containing GPR31 and SERPINB9 genes were associated with telomere length in long-term meditators with a strong statistical trend when correcting for multiple testing. Notably, age showed no association with telomere length in the group of long-term meditators. These results may suggest that long-term meditation could be related to epigenetic mechanisms, in particular gene-specific DNA methylation changes at distinct subtelomeric regions.

Effects of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors on ageing: Molecular mechanisms

Human ageing is determined by degenerative alterations and processes with different manifestations such as gradual organ dysfunction, tissue function loss, increased population of aged (senescent) cells, incapability of maintaining homeostasis and reduced repair capacity, which collectively lead to an increased risk of diseases and death. The inhibitors of HMG-CoA reductase (statins) are the most widely used lipid-lowering agents, which can reduce cardiovascular morbidity and mortality. Accumulating evidence has documented several pleiotropic effects of statins in addition to their lipid-lowering properties. Recently, several studies have highlighted that statins may have the potential to delay the ageing process and inhibit the onset of senescence. In this review, we focused on the anti-ageing mechanisms of statin drugs and their effects on cardiovascular and non-cardiovascular diseases.

Biochemical profile, eating habits, and telomere length among Brazilian children and adolescents

OBJECTIVES

Lifestyle, obesity, and eating habits are emerging as determinants for the instability of telomeres. The increase in childhood and adolescent obesity and the association of biochemical profiles and dietary components with telomere length (TL) makes it an important issue in nutritional research. The aim of the present study was to investigate TL and its association with ethnic background, adiposity, clinical and biochemical parameters, and dietary patterns among Brazilian children and adolescents.

METHODS

A cross-sectional study encompassing 981 children and adolescents between 7 and 17 y of age was performed. Dietary intake habits, anthropometry, and clinical data were collected. TL analysis was performed by quantitative polymerase chain reaction.

RESULTS

Children presented significantly longer TL than adolescents (P = 0.046). Participants who self-declared as black, mulatto, or brown (P < 0.001) also showed longer TL than those who were white. Regarding biochemical parameters, individuals with altered glucose levels had shorter TL than normoglycemic participants in the total sample (P = 0.014). Such difference remained statistically significant in adolescents (P = 0.019). Participants who reported eating fruits and vegetables regularly had longer TL than those who did not (P < 0.001).

CONCLUSION

The results suggested that both biochemical parameters and the intake of antioxidant-rich food, such as fruits and vegetables, are associated with the stability of telomere biology among young Brazilians.

Milk Fat Intake and Telomere Length in U.S. Women and Men: The Role of the Milk Fat Fraction

The associations between milk intake frequency and milk fat consumption and telomere length, an index of biological aging, were studied using an NHANES sample of 5,834 U.S. adults and a cross-sectional design. The milk consumption variables were assessed with the NHANES Diet Behavior and Nutrition questionnaire. The quantitative polymerase chain reaction method was used to measure leukocyte telomere length. Results showed that milk consumption frequency was not related to telomere length; however, there was a strong association between milk fat intake and telomere length. With the sample delimited to milk drinkers only, milk fat intake was linearly and inversely related to telomere length, after adjusting for the covariates (F = 8.6, P = 0.0066). For each 1 percentage point increase in milk fat consumed (e.g., 1% to 2%), adults had more than 4 years of additional biological aging. With milk fat intake divided into 5 categories (i.e., milk abstainers, nonfat, 1%, 2%, and full-fat milk), mean telomere lengths differed across the categories (F = 4.1, P = 0.0093). The mean telomere difference between the extremes of milk fat intake (nonfat vs. full-fat) was 145 base pairs, representing years of additional biological aging for full-fat milk consumers. Effect modification testing indicated that the milk fat and cellular aging association may be partly due to saturated fat intake differences across the milk fat groups. When the sample was delimited to adults reporting only high total saturated fat intake (tertile 3), the milk fat and telomere relationship was strong. However, when the sample was restricted to adults reporting only low saturated fat consumption (tertile 1), there was no relationship between milk fat intake and telomere length. Overall, the findings highlight an association of increased biological aging in U.S. adults who consumed high-fat milk. The results support the latest Dietary Guidelines for Americans (2015–2020), which recommend consumption of low-fat milk, but not high-fat milk, as part of a healthy diet.

Genetic polymorphisms, mRNA expression levels of telomere-binding proteins, and associates with telomere damage in PAHs-Exposure workers

Coke oven emissions (COEs), confirmed human carcinogens, are mainly composed of polycyclic aromatic hydrocarbons (PAHs). Telomere shortening in blood leukocytes has been associated with COEs, and polymorphisms in metabolic enzymes. However, the relationship between polymorphisms in telomere related genes and telomere shortening in COEs exposed workers has never been evaluated. Therefore, we measured telomere length and mRNA expression levels of telomere-binding proteins (TBPs) by qPCR method in leucocyte from 544 COEs exposed workers and 238 office staffs (referents). Flight mass spectrometry was used to perform the genotyping of selected functional and susceptible SNPs. The results showed that the telomere length in the exposure group 0.75(0.51,1.08) was significantly shorter than that in the control group 1.05(0.76,1.44) (P < 0.001). The mRNA expression levels of TPP1, TERF1 and TERF2 genes in the exposure group were significantly lower than those in the control group (P < 0.05), the mRNA expression level of POT1 in the exposure group was significantly higher than that in the control group (P < 0.05). We used the wild homozygous genotype as a reference, subjects carrying TERT rs2736109 AA, TERT rs3215401 CC and TERT rs2736100 GT + GG genotypes had significantly longer telomere length in the exposure group (P < 0.05). In conclusion, the workers exposed to COEs had shorter telomere length, which was regulated by the TPP1, TERF1, TERF2 and POT1 genes expression levels, and the gene polymorphisms of TERT gene were associated with the telomere length among PAHs-exposure workers.

Telomere Length: A Potential Biomarker for the Risk and Prognosis of Stroke

Stroke is one of the leading causes of death and disability worldwide. Age is associated with increased risk of stroke, while telomere length shortening plays a pivotal role in the process of aging. Moreover, telomere length shortening is associated with many risk factors of stroke in addition to age. Accumulated evidence shows that short leukocyte telomere length is not only associated with stroke occurrence but also associated with post-stroke recovery in the elderly population. In this review, we aimed to summarize the association between leukocyte telomere length and stroke, and discuss that telomere length might serve as a potential biomarker to predict the risk and prognosis of stroke.

Pistachio consumption modulates DNA oxidation and genes related to telomere maintenance: a crossover randomized clinical trial

BACKGROUND

Telomere attrition may play an important role in the pathogenesis and severity of type 2 diabetes (T2D), increasing the probability of β cell senescence and leading to reduced cell mass and decreased insulin secretion. Nutrition and lifestyle are known factors modulating the aging process and insulin resistance/secretion, determining the risk of T2D.

OBJECTIVES

The aim of this study was to evaluate the effects of pistachio intake on telomere length and other cellular aging-related parameters of glucose and insulin metabolism.

METHODS

Forty-nine prediabetic subjects were included in a randomized crossover clinical trial. Subjects consumed a pistachio-supplemented diet (PD, 50 E% [energy percentage] carbohydrates and 33 E% fat, including 57 g pistachios/d) and an isocaloric control diet (CD, 55 E% carbohydrates and 30 E% fat) for 4 mo each, separated by a 2-wk washout period. DNA oxidation was evaluated by DNA damage (via 8-hydroxydeoxyguanosine). Leucocyte telomere length and gene expression related to either oxidation, telomere maintenance or glucose, and insulin metabolism were analyzed by multiplexed quantitative reverse transcriptase-polymerase chain reaction after the dietary intervention.

RESULTS

Compared with the CD, the PD reduced oxidative damage to DNA (mean: -3.5%; 95% CI: -8.07%, 1.05%; P = 0.009). Gene expression of 2 telomere-related genes (TERT and WRAP53) was significantly upregulated (164% and 53%) after the PD compared with the CD (P = 0.043 and P = 0.001, respectively). Interestingly, changes in TERT expression were negatively correlated to changes in fasting plasma glucose concentrations and in the homeostatic model assessment of insulin resistance.

CONCLUSIONS

Chronic pistachio consumption reduces oxidative damage to DNA and increases the gene expression of some telomere-associated genes. Lessening oxidative damage to DNA and telomerase expression through diet may represent an intriguing way to promote healthspan in humans, reversing certain deleterious metabolic consequences of prediabetes. This study was registered at clinicaltrials.gov as NCT01441921.

Association between internet gaming addiction and leukocyte telomere length in Korean male adolescents

Internet gaming addiction (IGA) has been associated with many negative health outcomes, especially for youth. In particular, the potential association between IGA and leukocyte telomere length (LTL) has yet to be examined. In this study we compared LTL in Korean male adolescents with and without IGA and examined the association between LTL and autonomic functions. Specifically, plasma catecholamine, serum cortisol, and psychological stress levels were measured as autonomic functions. Data were collected using participant blood samples analyzed for LTL, catecholamine, and cortisol levels and a set of questionnaires to assess IGA and psychological stress levels of the participants. The LTL measurements were made using a qPCR-based technique, and the relative LTL was calculated as the telomere/single copy (T/S) ratio. T/S ratio was significantly shorter in the IGA group than in the non-IGA group (150.43 ± 6.20 and 187.23 ± 6.42, respectively; p < .001) after adjusting for age. In a univariate regression analysis, age, daily Internet gaming time, IGA score, and catecholamine level (epinephrine and norepinephrine) were significantly associated with T/S ratio. However, duration of Internet gaming exposure, dopamine, cortisol, and psychological stress levels were not found to be associated with T/S ratio. In the final multiple linear regression model, age, daily Internet gaming time, and epinephrine level showed statistically significant relationships with T/S ratio. Our results indicate that in addition to age, involvement in excessive Internet gaming may induce LTL shortening in male adolescents, which may be partially attributable to changes in autonomic function such as catecholamine level. These findings further understanding of the health effects of IGA and highlight the need for screening and intervention strategies for male adolescents with IGA.

Leukocyte Telomere Length Reflects Prenatal Stress Exposure, But Does Not Predict Atopic Dermatitis Development at 1 Year

Purpose

Prenatal maternal stress affects offspring's atopic dermatitis (AD) development, which is thought to be mediated by the oxidative stress. We aimed to evaluate the difference in leukocyte telomere length (LTL), a marker for exposure to oxidative stress, according to the prenatal stress exposure and the later AD development.

Methods

From a birth cohort (the COhort for Childhood Origin of Asthma and allergic diseases) that had displayed a good epidemiologic association between the exposure to prenatal stress and AD development in the offspring, we selected 68 pairs of samples from 4 subject groups based on the level of prenatal maternal stress and later AD development. The LTL was measured from both cord blood and 1-year peripheral blood, and their LTLs were compared between subject groups. Finally, the proportion of AD development was examined in the subject groups that are reclassified based on subjects' exposure to prenatal stress and there LTL.

Results

Cord-blood LTL was shorter in prenatally stressed infants than in unstressed ones (P = 0.026), which difference was still significant when subjects became 1 year old (P = 0.008). LTL of cord blood, as well as one of the 1-year peripheral blood, was not different according to later AD development at 1 year (P = 0.915 and 0.174, respectively). Shorter LTL made no increase in the proportion of later AD development in either prenatally high-stressed or low-stressed groups (P = 1.000 and 0.473, respectively).

Conclusions

Cord-blood LTL may reflect subjects' exposure to maternal prenatal stress. However, the LTL shortening is not a risk factor of increasing AD development until the age of 1, and a longer investigation may be necessary for validation. Currently, the results doubt the role of LTL shortening as a marker for risk assessment tool for the prenatal stress associated with AD development in the offspring.

Pivotal role of carnosine in the modulation of brain cells activity: Multimodal mechanism of action and therapeutic potential in neurodegenerative disorders

Carnosine (β-alanyl-l-histidine), a dipeptide, is an endogenous antioxidant widely distributed in excitable tissues like muscles and the brain. Although discovered more than a hundred years ago and having been extensively studied in the periphery, the role of carnosine in the brain remains mysterious. Carnosinemia, a rare metabolic disorder with increased levels of carnosine in urine and low levels or absence of carnosinase in the blood, is associated with severe neurological symptoms in humans. This review deals with the role of carnosine in the brain in both physiological and pathological conditions, with a focus on preclinical evidence suggesting a high therapeutic potential of carnosine in neurodegenerative disorders. We review carnosine and carnosinemia's discoveries and the extensive research on the role and benefits of carnosine in the periphery. We then turn to carnosine's biochemistry and distribution in the brain. Using an array of recent observations as a foundation, we draw a parallel with the role of carnosine in muscles and speculate on the role of carnosine in promoting the metabolic support of neurons by glial cells. Finally, carnosine has been shown to exert a multimodal activity including inhibition of protein cross-linking and aggregation of amyloid-β and related proteins, free radical generation, nitric oxide detoxification, and an anti-inflammatory activity. It could thus play an important role in the prevention and treatment of neurodegenerative diseases such as Alzheimer's disease. We discuss the potential of carnosine in this context and speculate on new preclinical research directions.

Particulate Air Pollution, Blood Mitochondrial DNA Copy Number, and Telomere Length in Mothers in the First Trimester of Pregnancy: Effects on Fetal Growth

Growing evidences have shown that particulate matter (PM) exposures during pregnancy are associated with impaired fetal development and adverse birth outcomes, possibly as a result of an exaggerated systemic oxidative stress and inflammation. Telomere length (TL) is strongly linked to biological age and is impacted by oxidative stress. We hypothesized that PM exposure during different time windows in the first trimester of pregnancy influences both mitochondrial DNA copy number (mtDNAcn), an established biomarker for oxidative stress, and TL. Maternal blood TL and mtDNAcn were analysed in 199 healthy pregnant women recruited at the 11th week of pregnancy by quantitative polymerase chain reaction. We also examined whether maternal mtDNAcn and TL were associated with fetal growth outcomes measured at the end of the first trimester of pregnancy (fetal heart rate, FHR; crown-rump length, CRL; and nuchal translucency, NT) and at delivery (birth weight, length, head circumference). The possible modifying effect of prepregnancy maternal body mass index was evaluated. PM₁₀ exposure during the first pregnancy trimester was associated with an increased maternal mtDNAcn and a reduced TL. As regards ultrasound fetal outcomes, both FHR and CRL were positively associated with PM_2.5, whereas the association with FHR was confirmed only when examining PM₁₀ exposure. PM₁₀ was also associated with a reduced birth weight. While no association was found between mtDNAcn and CRL, we found a negative relationship between mtDNAcn and fetal CRL only in overweight women, whereas normal-weight women exhibited a positive, albeit nonsignificant, association. As abnormalities of growth in utero have been associated with postnatal childhood and adulthood onset diseases and as PM is a widespread pollutant relevant to the large majority of the human population and obesity a rising risk factor, our results, if confirmed in a larger population, might represent an important contribution towards the development of more targeted public health strategies.

Racial differences in maternal and umbilical cord blood leukocyte telomere length and their correlations

PURPOSE

Telomere length at birth sets the baseline for telomere shortening and may influence adult disease risk like cancer. Telomere length is heritable, but may also be a marker of exposures in utero, including those influencing racial differences in risk. We examined racial differences in telomere length in maternal and umbilical cord blood from male neonates, and maternal-neonate correlations to generate hypotheses.

METHODS

Black and white pregnant women were recruited in 2006-2007 and followed to postpartum. Data came from questionnaires and medical records. Relative telomere length was measured by qPCR in leukocyte DNA. We estimated mean telomere length in mothers and neonates (n = 55 pairs) using linear regression and maternal-cord blood Spearman correlations, overall and by race.

RESULTS

Black mothers had shorter age- and plate-adjusted telomere length (2.49, 95% CI 2.11-2.86) than whites (2.92, 95% CI 2.63-3.22; p = 0.1) and black neonates had shorter telomere length (2.58, 95% CI 2.16-3.01) than whites (3.13, 95% CI 2.79-3.47; p = 0.1), though not statistically significant. Differences were attenuated after further adjustment for maternal factors. Maternal-cord blood correlations were moderate (r = 0.53, p < 0.0001), and did not differ by race.

CONCLUSION

Telomere length may differ by race at birth due to both inherited and racial differences in maternal factors. This study was for hypothesis generation and results should be followed up in larger studies.

Dietary Fiber and Telomere Length in 5674 U.S. Adults: An NHANES Study of Biological Aging

The relationship between fiber intake and telomere length was evaluated using a cross-sectional design and an NHANES sample of 5674 U.S. adults. Another purpose was to test the impact of potential confounders on the association. Fiber consumption was measured using a 24 h recall and telomere length was indexed using the quantitative polymerase chain reaction method. Overall, the U.S. adults had low fiber intake (median: 6.6 g per 1000 kcal)—less than one-half the recommendation of the Dietary Guidelines for Americans. With age, gender, race, housing status, and misreported energy intake controlled, the relationship between fiber intake per 1000 kcal and telomere length was linear (F = 9.5, p = 0.0045). Specifically, for each 1 g increment in fiber intake per 1000 kcal, telomeres were 8.3 base pairs longer. Because each additional year of chronological age was associated with telomeres that were 15.5 base pairs shorter, results suggest that a 10 g increase in fiber intake per 1000 kcal would correspond with telomeres that are 83 base pairs longer. On average, this would equate to 5.4 fewer years of biologic aging (83 ÷ 15.5). With smoking, BMI, alcohol use, and physical activity controlled, as well as the other covariates, each 10 g increment in fiber accounted for telomeres that were 67 base pairs longer (F = 7.6, p = 0.0101), a biologic aging difference of about 4.3 years. In conclusion, significant fiber consumption accounts for longer telomeres and less biologic aging than lower levels of fiber intake.

Short Telomere Length is Associated with Aging, Central Obesity, Poor Sleep and Hypertension in Lebanese Individuals

In Lebanon, data stemming from national cross-sectional surveys indicated significant increasing trends in the prevalence of cardiovascular diseases and associated behavioral and age-related risk factors. To our knowledge, no data are available on relative telomere length (RTL) as a potential biomarker for age-related diseases in a Lebanese population. The aim of this study was to evaluate whether there is an association between RTL and demographic characteristics, lifestyle habits and diseases in the Lebanese. This was a cross-sectional study of 497 Lebanese subjects. Peripheral blood RTL was measured by amplifying telomere and single copy gene using real-time PCR. Mean ± SD RTL was 1.42 ± 0.83, and it was categorized into 3 tertiles. Older age (P=0.002) and wider waist circumference (WC) (P=0.001) were statistically significantly associated with shorter RTL. Multinomial logistic regression showed that subjects who had some level of sleeping difficulty had a statistically significantly shorter RTL when compared to those with no sleeping difficulties at all [OR (95% CI): 2.01 (1.11-3.62) in the first RTL tertile]. Importantly, statistically significantly shorter RTL was found with every additional 10 cm of WC [OR (95% CI): 1.30 (1.11-1.52) for first RTL tertile]. In addition, and after performing the multivariate logistic regression and adjusting for “predictors” of RTL, the odds of having hypertension or being treated for hypertension were higher in patients who had shorter RTL: OR (95% CI): 2.45 (1.36-4.44) and 2.28 (1.22-4.26) in the first RTL tertiles respectively with a similar trend, though not statistically significant, in the second RTL tertiles. This is the first study in Lebanon to show an association between age, central obesity, poor sleep and hypertension and RTL. It is hoped that telomere length measurement be potentially used as a biomarker for biological age and age-related diseases and progression in the Lebanese.

Evaluation of cerebral blood flow change after cigarette smoking using quantitative MRA

BACKGROUND AND OBJECTIVE

Changes in cerebral blood flow (CBF) immediately after cigarette smoking (CS) are still unclear. Our purpose was to evaluate the hemodynamic changes in each intracranial vessel after CS by using quantitative magnetic resonance angiography (MRA).

MATERIAL AND METHODS

Fifteen healthy male smokers less than 45 years old with more than 3 pack-year smoking history were enrolled in this study. The hemodynamic change in the vessels, represented by cerebral flow rate (CFR, ml/s) and flow velocity (FV, cm/s), was quantitatively measured in eleven vascular segments of the brain using phase-contrast MRA. Two sets of data at each vessel before and after CS were statistically analyzed by paired t-test. Three of 15 participants, as a control group, followed all the procedures but did not smoke.

RESULTS

Total CFR of the distal intracranial vessels (anterior, middle, and posterior cerebral arteries; ACA, MCA, and PCA) was significantly reduced after CS by 7.3% (847 vs. 785 ml/s, p = 0.024). Such flow changes were statistically more significant in the anterior circulation (ACA and MCA) compared to the posterior circulation (PCA). All distal intracranial vessels did not have significant FV change while peak systolic velocity and mean velocity dropped 7.4 and 4.3% and pulsatility index decreased 10.9% in the internal carotid artery. Regarding cross-sectional areas, all distal intracranial vessels showed diminished, and only MCA had a statistical significance (9.9 vs. 9.3 mm2, p = 0.016).

CONCLUSIONS

There was a significant decrease of CFR after CS especially in the anterior circulation of twelve young male smokers. Considering the changes of FV and cross-sectional area all together, it can be suggested that cerebrovascular impedance increased after CS especially at the main trunk level of the distal intracranial vessels (ACA, MCA, and PCA).

Physical activity and telomere length in U.S. men and women: An NHANES investigation

The principal objective was to determine the extent to which physical activity (PA) accounts for differences in leukocyte telomere length (LTL) in a large random sample of U.S. adults. Another purpose was to assess the extent to which multiple demographic and lifestyle covariates affect the relationship between PA and LTL. A total of 5823 adults from the National Health and Nutrition Examination Survey (NHANES 1999-2002) were studied cross-sectionally. Employing the quantitative polymerase chain reaction method, LTL was compared to standard reference DNA. PA was indexed using MET-minutes using self-reported frequency, intensity, and duration of participation in 62 physical activities. Covariates were controlled statistically. Telomeres were 15.6 base pairs shorter for each year of chronological age (F=723.2, P<0.0001). PA was inversely related to LTL after adjusting for all the covariates (F=8.3, P=0.0004). Telomere base pair differences between adults with High activity and those in the Sedentary, Low, and Moderate groups were 140, 137, and 111, respectively. Adults with High activity were estimated to have a biologic aging advantage of 9years (140 base pairs÷15.6) over Sedentary adults. The difference in cell aging between those with High and Low activity was also significant, 8.8years, as was the difference between those with High and Moderate PA (7.1years). Overall, PA was significantly and meaningfully associated with telomere length in U.S. men and women. Evidently, adults who participate in high levels of PA tend to have longer telomeres, accounting for years of reduced cellular aging compared to their more sedentary counterparts.

Basic science and pathogenesis of ageing with HIV: potential mechanisms and biomarkers

: The increased prevalence of age-related comorbidities and mortality is worrisome in ageing HIV-infected patients. Here, we aim to analyse the different ageing mechanisms with regard to HIV infection. Ageing results from the time-dependent accumulation of random cellular damage. Epigenetic modifications and mitochondrial DNA haplogroups modulate ageing. In antiretroviral treatment-controlled patients, epigenetic clock appears to be advanced, and some haplogroups are associated with HIV infection severity. Telomere shortening is enhanced in HIV-infected patients because of HIV and some nucleoside analogue reverse transcriptase inhibitors. Mitochondria-related oxidative stress and mitochondrial DNA mutations are increased during ageing and also by some nucleoside analogue reverse transcriptase inhibitors. Overall, increased inflammation or 'inflammageing' is a major driver of ageing and could result from cell senescence with secreted proinflammatory mediators, altered gut microbiota, and coinfections. In HIV-infected patients, the level of inflammation and innate immunity activation is enhanced and related to most comorbidities and to mortality. This status could result, in addition to age, from the virus itself or viral protein released from reservoirs, from HIV-enhanced gut permeability and dysbiosis, from antiretroviral treatment, from frequent cytomegalovirus and hepatitis C virus coinfections, and also from personal and environmental factors, as central fat accumulation or smoking. Adaptive immune activation and immunosenescence are associated with comorbidities and mortality in the general population but are less predictive in HIV-infected patients. Biomarkers to evaluate ageing in HIV-infected patients are required. Numerous systemic or cellular inflammatory, immune activation, oxidative stress, or senescence markers can be tested in serum or peripheral blood mononuclear cells. The novel European Study to Establish Biomarkers of Human Ageing MARK-AGE algorithm, evaluating the biological age, is currently assessed in HIV-infected patients and reveals an advanced biological age. Some enhanced inflammatory or innate immune activation markers are interesting but still not validated for the patient's follow-up. To be able to assess patients' biological age is an important objective to improve their healthspan.

Is Leukocyte Telomere Length Related with Lung Cancer Risk?: A Meta-Analysis

BACKGROUND

Epidemiological studies have probed the correlation between telomere length and the risk of lung cancer, but their findings are inconsistent in this regard. The present meta-analysis study has been carried out to demonstrate the association between relative telomere length in peripheral blood leukocytes and the risk of lung cancer using an established Q-PCR technique.

METHODS

A systematic search was carried out using PubMed, EMBASE, and ISI before 2015. A total of 2925 cases of lung cancer and 2931 controls from 9 studies were employed to probe the relationship between lung cancer and telomere length .ORs were used at 95% CI. Random-effects models were used to investigate this relationship based on the heterogeneity test. Heterogeneity among studies was analyzed employing subgroup analysis based on type studies and the year of publication.

RESULTS

Random-effects meta-analysis revealed that patients with lung cancer were expected to have shorter telomere length than the control (1.13, 95% CI: 0.82-1.81, P=0.46). The summary of the pooled ORs of telomere length in adenocarcinoma lung cancer patients was 1 (95%CI=0.68-1.47, I2=93%) compared to patients with squamous cell lung cancer, which was 1.78 (95% CI=1.25-2.53, I2=3.9%). The meta-regression revealed that the effect of telomere length shortening, decreased and increased with the year of publication and the age of risks to lung cancer, was clearly related to short telomeres lengths.

CONCLUSION

Lung cancer risks clearly related with short telomeres lengths. In patients with breathing problems, lung cancer risk can be predicted by telomere length adjustment with age, sex, and smoking.