Examining the gender difference in the association between metabolic syndrome and the mean leukocyte telomere length

Leukocyte telomere length in subjects with metabolic dysfunction-associated steatotic liver disease

BACKGROUND AND STUDY AIMS

This study aimed to examine the association between peripheral leukocyte telomere length and indicators of metabolic abnormalities in subjects with metabolic dysfunction-associated steatotic liver disease (MASLD) assessed by magnetic resonance imaging (MRI).

PATIENTS AND METHODS

This cross-sectional study included adults over 20 years with body mass index (BMI) of over >25 kg/m2 and sonographic evidence of hepatic steatosis. The subjects were evaluated by clinical and biochemical variables, determination of hepatic fat fraction by MRI and relative peripheral leukocyte telomere length by quantitative real-time polymerase chain reaction.

RESULTS

Thirty-two subjects (22 men and 10 women) with MASLD were included, with a median age of 40 years, median BMI of 33.75 kg/m2, median HFF 19 %, and median relative T/S ratio of 0.64. Subjects with relative T/S ratio below the median had significantly higher age, lower BMI, higher AST serum levels, higher GGT serum levels, lower serum ferritin levels, and higher FIB4 score. In a multivariable logistic regression model considering relative T/S ratio below or above the median only age was significantly associated with relative T/S ratio. Our findings suggest that age is the most important factor associated with telomere length among subjects with MASLD.

CONCLUSION

Our findings suggest that age is the most important factor associated with telomere length among subjects with MASLD.

The association of metabolic syndrome with telomere length as a marker of cellular aging: a systematic review and meta-analysis

Background

It has been suggested that metabolic syndrome (MetS) accelerates the aging process, potentially contributing to the development of age-related complications. Available studies examining the relation of MetS to telomere length (TL), a putative biological marker of aging, have yielded inconclusive findings. This meta-analysis was performed to investigate the association between MetS and TL.

Methods

A comprehensive systematic search was conducted in PubMed and Scopus databases to identify relevant literature published up to February 2024. Standard mean difference (SMD) and standardized beta coefficient (β) with their 95% confidence intervals (CI) were used as effect sizes to measure the associations using the random effects model.

Results

A total of nine studies, comprising a total sample size of 8,606 participants, were eligible for the meta-analysis. No significant difference in mean TL was found between patients with and without MetS (SMD = -0.03, 95%CI = -0.17 to 0.10), with a significant heterogeneity across the studies (I 2 = 89.7.0%, p ≤ 0.001). In contrast, it was revealed that MetS is negatively related to TL (β = -0.08, 95%CI = -0.15 to -0.004). In the subgroup analysis, this finding was supported by the International Diabetes Federation (IDF) definition of MetS.

Conclusion

This meta-analysis highlighted that MetS may be linked to a shorter TL. Additional studies are required to confirm this finding.

The relationship between greenspace exposure and telomere length in the National Health and Nutrition Examination Survey

The exposome, reflecting the range of environmental exposures individuals encounter throughout their life, can influence a variety of health outcomes and can play a role in how the environment impacts our genes. Telomeres, genetic structures regulating cell growth and senescence, are one pathway through which the exposome may impact health. Greenspace exposure, representing the amount of green areas in one's neighborhood, is one component of the exposome and has been associated with multiple health benefits. To investigate the potential link between greenspace exposure and telomere length, we analyzed data from the 1999-2001 National Health and Nutrition Examination Survey (NHANES) sample. Our study examined individual, risk, and contextual factors. We found that greater greenspace exposure in one's neighborhood was associated with longer telomere lengths when considering individual and risk factors, suggesting a positive effect of living in greener neighborhoods. However, this relationship became non-significant when contextual factors, such as air pollution and deprivation, were included in the analysis. These findings highlight a complex relationship between greenspace and telomere length, warranting further research to explore contextual factors in detail.

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

OBJECTIVE

To 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).

METHODS

The 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.

RESULTS

We 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.

CONCLUSIONS

Our 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.

Metabolic syndrome and transaminases: systematic review and meta-analysis

BACKGROUND

Metabolic syndrome (MetS) is a group of metabolic abnormalities characterised by hypertension, central obesity, dyslipidaemia and dysregulation of blood glucose, associated with the risk of diabetes, cardiovascular disease and overall mortality. The presence of elevated liver enzymes may precede the development of MetS, with alterations of the liver being observed that are directly related to metabolic problems. The study aims to provide the best evidence on the association between liver enzymes (ALT, AST, GGT) and MetS by determining the effect size of these biomarkers.

METHODS

A systematic review and meta-analysis of studies indexed in PubMed and Scopus databases were performed. Study quality was assessed using the STROBE tool. The Grade Pro tool was used to evaluate the evidence, and the quantitative synthesis was performed using RevMan (Cochrane Collaboration).

RESULTS

Seventeen articles comparing liver enzyme concentrations between 76,686 with MetS (MetS+) and 201,855 without MetS (MetS-) subjects were included. The concentration of ALT, AST and GGT in the MetS + subjects was significantly higher than in the control group 7.13 IU/L (CI95% 5.73-8.54; p < 0.00001; I2 = 96%), 2.68 IU/L (CI95% 1.82-3.54; p < 0.00001; I2 = 96%) and 11.20 IU/L (CI95% 7.11-15.29; p < 0.00001; I2 = 96%), respectively.

CONCLUSIONS

The evaluation of the relationship of liver enzymes in the pathophysiological process of MetS could lead to new insights into early diagnosis.

Association between metabolic syndrome and uric acid: a systematic review and meta-analysis

This systematic review and meta-analysis aim to provide the best evidence on the association between metabolic syndrome (MetS) and uric acid (UA) by determining the size of the effect of this biomarker on MetS. The review protocol is registered with PROSPERO (CRD42021231124). The search covered the PubMed and Scopus databases. Methodological quality was assessed with the STROBE tool, overall risk of bias with RevMan (Cochrane Collaboration) and quality of evidence with Grade Pro. Initially, 1582 articles were identified. Then, after excluding duplicates and reviewing titles and abstracts, 1529 articles were excluded from applying the eligibility criteria. We included 43 papers (56 groups) comparing UA concentrations between subjects 91,845 with MetS and 259,931 controls. Subjects with MetS had a higher mean UA of 0.57 mg/dl (95% CI 0.54-0.61) (p < 0.00001). Given the heterogeneity of the included studies, the researchers decided to perform subgroups analysis. Men with MetS have a higher UA concentration mg/dl 0.53 (95% CI 0.45-0.62, p < 0.00001) and women with MetS 0.57 (95% CI 0.48-0.66, p < 0.00001) compared to subjects without MetS. Assessment of UA concentration could provide a new avenue for early diagnosis of MetS, as a new biomarker and the possibility of new therapeutic targets.

Three months-longitudinal changes in relative telomere length, blood chemistries, and self-report questionnaires in meditation practitioners compared to novice individuals during midlife

Aging accelerates during midlife. Researches have shown the health benefits of mind-body intervention (MBI). However, whether MBI is involved with aging process has not been well understood. In this study, we approach to examine the relations of MBI with this process by investigating an aging marker of the peripheral blood, blood chemistry, and self-report questionnaires. A quasi-experimental design was applied. Experienced MBI practitioners participated in a 3-month intensive meditation training, while the age, gender-matched MBI-naïve controls led a normal daily life. Measurements were taken at before and after the 3 months for relative telomere length (RTL), blood chemistry, and self-report questionnaires including items about sleep quality, somatic symptoms, depression, anxiety, stress, emotional intelligence (EI), and self-regulation. For RTL, the repeated measures analysis of variance showed a significant group*time interaction (P = .013) with a significant post hoc result (P = .030) within the control group: RTL was significantly reduced in the control while it was maintained in the meditation group. In repeated measures analysis of variance for blood chemistries, there were significant group differences between the groups in glucose and total protein. In the post hoc comparison analysis, at post measurements, the meditation group exhibited significantly lower values than the control group in both glucose and total protein. There were significant group-wise differences in the correlations of RTL with triglyceride (TG), high-density lipoprotein (HDL), glutamic oxaloacetic transaminase and glutamic pyruvic transaminase. Any of self-report results did not show significant changes in group*time interaction. However, there were group differences with significant (P < .05) or a tendency (.05 < P < .1) level. There were significant improvements in depression, stress and EI as well as tendencies of improvement in sleep quality and anxiety, in the meditation group compared to the control group. Our results suggest that meditation practice may have a potential to modify aging process in molecular cellular level combined with changes in psychological dimension.

The effect of metformin treatment on leukocyte telomere length in patients with polycystic ovary syndrome: a prospective case-control study

PURPOSE

The study aimed to investigate the effect of metformin treatment on leukocyte telomere length (LTL) and the relationship of LTL with C-reactive protein (CRP), homocysteine, albumin, complete blood count, and HOMA-IR values in patients with polycystic ovary syndrome (PCOS).

MATERIAL AND METHOD

A prospective case-control study consisting of 30 women with PCOS and 30 healthy women without PCOS was performed. The relationship between clinical and laboratory parameters and LTL was analyzed. PCOS patients were treated with metformin (850 mg/day) for three months. Before treatment (BT) and after treatment (AT), each patient's LTL was evaluated and compared with the control group.

RESULTS

In the comparison between PCOS and control groups, the difference was significant for LTL, age, body mass index (BMI), and CRP (p = 0.002; p < 0.001; p = 0.001; p = 0.01, respectively). In PCOS patients, the difference between BT and AT, LTL was not statistically significant (BT: 6.06 ± 2.12; AT: 6.30 ± 1.93; p = 0.623; 95% C.I: - 1.22-0.74); however, the difference for weight was significant (BT: 83.78 ± 15.31; AT: 80.62 ± 15.40; p = 0.02; 95% CI: 1.34-4.99). The logistic regression model established by BMI (group 1: 21-24, group 2: 24-29, group 3: 29-34, group 4: > 34), age, and RDW, which predicted the PCOS group by affecting the LTL level, was statistically significant (p < 0.001/PPV = 96.3%; NPV = 88.5%). Each unit reduction in telomere length increased women's probability of PCOS by 0.4 times (p = 0.013; OR = 0.419, 95% CI: 0.211-0.835).

CONCLUSION

Although statistically insignificant, LTL increased after metformin use in PCOS patients, and the mean weight loss reduction was statistically significant. Telomere shortening increased the likelihood of PCOS 0.4 times.

Gender Difference in Associations Between Telomere Length and Risk Factors in Patients With Stroke

Multiple risk factors of stroke are associated with telomere length shortening. Although leukocyte telomere length (LTL) is shorter in patients with stroke, the heterogeneity is high. Risk factors may be differentially associated with LTL in male and female patients contributing to the heterogeneity. However, the gender difference in associations between LTL and risk factors in stroke patients has not been investigated. In this study, we investigated the gender difference in associations between LTL and risk factors in 312 stroke patients. Real-time quantitative PCR was used to determine relative LTL, and multiple linear regression analysis was applied for association analyses. We found that LTL was negatively associated with triglyceride (TG) in all patients [β(95% CI) = −0.69 (−1.26, −0.11), P < 0.05] after adjusting confounders. Importantly, LTL was negatively associated with lack of exercise [β(95% CI) = −1.80 (−3.12, −0.49), P < 0.05] and LDL levels [β(95% CI) = −3.22 (−6.05, −0.390), P < 0.05] in male patients, while LTL was negatively associated with dyssomnia [β(95%CI) = −2.00 (−3.96, −0.07), P < 0.05] and diabetes [β(95%CI) = −2.13 (−4.10, −0.27), P < 0.01] in female patients. Our study showed that LTL is differently associated with risk factors in male and female patients with stroke, indicating that gender difference should be considered when LTL is potentially applied as an index of risk and prognosis for stroke. Our study also provides an insight into that gender differences should be considered when developing intervention strategies for stroke prevention and treatment.

Telomere and Telomerase: Biological Markers of Organic Vital Force State and Homeopathic Treatment Effectiveness

BACKGROUND

 Philosophical-scientific correlations described in previous studies suggest that the genome can be the biological representation of the vital force, whilst the disease-promoting epigenetic alterations would be the biological representation of the chronic miasmas. In this study, we expand the functional correlation between vital force and chromosomes, describing the mechanism of action of the telomere-telomerase complex in the context of physiological balance.

AIMS

 The aim of the work is to study the role of the telomere-telomerase complex in cell vitality, biological aging, and the health-disease process, with the goal of proposing the use of telomere length as a biomarker of the vital force state and the effectiveness of homeopathic treatment.

RESULTS

 Similar to the vital force, telomere length and telomerase enzyme activity play an important role in maintaining cellular vitality, biological longevity, and physiological homeostasis. Telomere shortening functions as a biomarker of vital imbalance and is associated with numerous diseases and health disorders. On the other hand, health-promotion practices neutralize the pathological shortening of the telomeres, acting therapeutically in diseases or age-dependent health disorders.

CONCLUSIONS

 As a hypothetical biomarker of the vital force state, an intra-individual analysis of the mean leukocyte telomere length before, during, and after homeopathic treatment can be used as a biomarker of therapeutic effectiveness.

Association of leukocyte telomere length with obesity-related traits in Asian children with early-onset obesity

BACKGROUND

Leukocyte telomere length (LTL) is associated with obesity and obesity-related traits, and there are ethnic-specific determinants of LTL.

OBJECTIVE

To evaluate LTL associations with obesity and metabolic parameters in Asian children with early-onset obesity.

METHODS

Genomic DNA was extracted from peripheral blood leukocytes of a cohort of children with (N = 371) and without obesity (N = 23), and LTL was measured using quantitative PCR (qPCR). Blood plasma was used for metabolic phenotyping. Statistical analysis was performed using SPSS and STATA.

RESULTS

Children with obesity had shorter LTL (coefficient = -0.683, P_Adj = 1.24 × 10^-3 ) as compared to children who were lean. LTL was found to be associated with waist circumference (coefficient = -0.326, P_Adj = 0.044) and skin-fold measures (coefficient between 0.267 and 0.301, P_Adj between 4.27 × 10^-4 and 7.06 × 10^-7 ) in children with obesity. However, no significant associations were observed between LTL and metabolic parameters, and between LTL and inflammatory cytokines. LTL also did not significantly mediate the risk of non-alcoholic fatty liver disease (NAFLD) in children with obesity.

CONCLUSIONS

We showed for the first time that Asian children with severe obesity had shorter LTL, and the shortening of LTL was associated with other adiposity measures including waist circumference and skin-fold measurements.

The association of telomere length with substance use disorders: a systematic review and meta-analysis of observational studies

BACKGROUND AND AIMS

Several recent studies have investigated the relationship between telomere length and substance use disorders with inconsistent results. We aimed to assess this association and to identify moderators of the relationship.

METHODS

Systematic review and meta-analysis. Selection criteria were observational studies reporting telomere length in people with a substance use disorder compared with a control group. Studies focused solely on nicotine addiction, employing other study designs, and non-human studies were excluded. Study selection and data extraction were independently conducted by two researchers following a standardized protocol and included studies until December 2019. Standardized mean differences were used as the effect size index [d; 95% confidence interval (CI)] and random-effects models were used for the meta-analysis. Cochran's Q-statistic, I² index, visual inspection of the forest plot and a 95% prediction interval were applied to verify study heterogeneity. Subgroup analyses and meta-regressions were conducted to explore heterogeneity. Small study effects were examined using the 'funnel plot', the Egger test, Duval & Tweedie's trim-and-fill method and the precision-effect test-precision-effect estimate with standard error (PET-PEESE) method. The risk of bias and the quality of evidence were assessed.

RESULTS

Ten studies (12 analysis units with 2671 cases and 4532 controls) met the selection criteria. An overall effect size of moderate magnitude was found (d₊  = -0.63; 95% CI = -1.00 and -0.26; P = 0.0008). A potential small study effect was detected, as well as large heterogeneity between studies (Q-statistic P < 0.001, I²  = 97.3%). Selection of controls, reporting laboratory quality control procedures and total sample size significantly affected the effect size. The quality of the evidence was very low, based on risk of bias analysis and the grading of recommendations assessment, development and evaluation (GRADE) system.

CONCLUSIONS

People with substance use disorders appear to have shorter telomere length than controls; however, this finding should be interpreted with caution due to the poor quality of the evidence.

Genetically Increased Telomere Length and Aging-Related Traits in the U.K. Biobank

Telomere length (TL) shortens over time in most human cell types and is a potential biomarker of aging. However, the causal association of TL on physical and cognitive traits that decline with age has not been extensively examined in middle-aged adults. Using a Mendelian randomization (MR) approach, we utilized genetically increased TL (GI-TL) to estimate the impact of TL on aging-related traits among U.K. Biobank (UKB) participants (age 40-69 years). We manually curated 53 aging-related traits from the UKB and restricted to unrelated participants of British ancestry (n = 337,522). We estimated GI-TL as a linear combination of nine TL-associated single nucleotide polymorphisms (SNPs), each weighted by its previously-reported association with leukocyte TL. Regression models were used to assess the associations between GI-TL and each trait. We obtained MR estimates using the two-sample inverse variance weighted (IVW) approach. We identified six age-related traits associated with GI-TL (Bonferroni-corrected threshold p < .001): pulse pressure (PP) (p = 5.2 × 10-14), systolic blood pressure (SBP) (p = 2.9 × 10-15), diastolic blood pressure (DBP) (p = 5.5 × 10-6), hypertension (p = 5.5 × 10-11), forced expiratory volume (FEV1) (p = .0001), and forced vital capacity (FVC) (p = 3.8 × 10-6). Under MR assumptions, one standard deviation increase in TL (~1,200 base pairs) increased PP, SBP, and DBP by 1.5, 2.3, and 0.8 mmHg, respectively, while FEV1 and FVC increased by 34.7 and 52.2 mL, respectively. The observed associations appear unlikely to be due to selection bias based on analyses including inverse probability weights and analyses of simulated data. These findings suggest that longer TL increases pulmonary function and blood pressure traits among middle-aged UKB participants.

Discrimination and Leukocyte Telomere Length by Depressive Symptomatology: The Jackson Heart Study

Background: Psychosocial stressors, such as perceived discrimination and depressive symptoms, may shorten telomeres and exacerbate aging-related illnesses. Methods: Participants from the Jackson Heart Study at visit 1 (2000–2004) with LTL data and Center for Epidemiological Studies-Depression (CES-D) scores (n = 580 men, n = 910 women) were utilized. The dimensions of discrimination scores (everyday, lifetime, burden of lifetime, and stress from lifetime discrimination) were standardized and categorized as low, moderate, and high. Coping responses to everyday and lifetime discrimination were categorized as passive and active coping. Multivariable linear regression analyses were performed to estimate the mean difference (standard errors-SEs) in LTL by dimensions of discrimination and coping responses stratified by CES-D scores < 16 (low) and ≥ 16 (high) and sex. Covariates were age, education, waist circumference, smoking and CVD status. Results: Neither everyday nor lifetime discrimination was associated with mean differences in LTL for men or women by levels of depressive symptoms. Burden of lifetime discrimination was marginally associated with LTL among women who reported low depressive symptoms after full adjustment (b = 0.11, SE = 0.06, p = 0.08). Passive coping with lifetime discrimination was associated with longer LTL among men who reported low depressive symptoms after full adjustment (b = 0.18, SE = 0.09, p < 0.05); and active coping with lifetime discrimination was associated with longer LTL among men who reported high depressive symptoms after full adjustment (b = 1.18, SE = 0.35, p < 0.05). Conclusions: The intersection of perceived discrimination and depressive symptomatology may be related to LTL, and the effects may vary by sex.

Minimal changes in telomere length after a 12-week dietary intervention with almonds in mid-age to older, overweight and obese Australians: results of a randomised clinical trial

Diet is a modifiable risk factor for chronic disease and a potential modulator of telomere length (TL). The study aim was to investigate associations between diet quality and TL in Australian adults after a 12-week dietary intervention with an almond-enriched diet (AED). Participants (overweight/obese, 50-80 years) were randomised to an AED (n 62) or isoenergetic nut-free diet (NFD, n 62) for 12 weeks. Diet quality was assessed using a Dietary Guideline Index (DGI), applied to weighed food records, that consists of ten components reflecting adequacy, variety and quality of core food components and discretionary choices within the diet. TL was measured by quantitative PCR in samples of lymphocytes, neutrophils, and whole blood. There were no significant associations between DGI scores and TL at baseline. Diet quality improved with AED and decreased with NFD after 12 weeks (change from baseline AED + 9·8 %, NFD - 14·3 %; P < 0·001). TL increased in neutrophils (+9·6 bp, P = 0·009) and decreased in whole blood, to a trivial extent (-12·1 bp, P = 0·001), and was unchanged in lymphocytes. Changes did not differ between intervention groups. There were no significant relationships between changes in diet quality scores and changes in lymphocyte, neutrophil or whole blood TL. The inclusion of almonds in the diet improved diet quality scores but had no impact on TL mid-age to older Australian adults. Future studies should investigate the impact of more substantial dietary changes over longer periods of time.

Telomere Length and Oxidative Stress and Its Relation with Metabolic Syndrome Components in the Aging

A great amount of scientific evidence supports that Oxidative Stress (OxS) can contribute to telomeric attrition and also plays an important role in the development of certain age-related diseases, among them the metabolic syndrome (MetS), which is characterised by clinical and biochemical alterations such as obesity, dyslipidaemia, arterial hypertension, hyperglycaemia, and insulin resistance, all of which are considered as risk factors for type 2 diabetes mellitus (T2DM) and cardiovascular diseases, which are associated in turn with an increase of OxS. In this sense, we review scientific evidence that supports the association between OxS with telomere length (TL) dynamics and the relationship with MetS components in aging. It was analysed whether each MetS component affects the telomere length separately or if they all affect it together. Likewise, this review provides a summary of the structure and function of telomeres and telomerase, the mechanisms of telomeric DNA repair, how telomere length may influence the fate of cells or be linked to inflammation and the development of age-related diseases, and finally, how the lifestyles can affect telomere length.

Diabetes, metabolic disease, and telomere length

Telomeres are regions of repetitive nucleotide sequences at the ends of chromosomes. Telomere length is a marker of DNA damage, which is often considered a biomarker for biological ageing, and has also been linked with cardiovascular disease, diabetes, and cancer. Emerging studies have highlighted the role of genetic and environmental factors, and explored the effect of modulating telomere length. We provide an overview of studies to date on diabetes and telomere length, and compare different methods and assays for evaluating telomere length and telomerase activity. We highlight the limitations of current studies and areas that warrant further research to unravel the link between diabetes and telomere length. The value of adding telomere length to clinical risk factors to improve risk prediction of diabetes and related complications also merits further investigation.

From culture to chromosomes: A mother-child dyadic study of acculturation, telomere lengths and body fat

Studies suggest that telomere lengths, a biomarker of aging, could also capture the physiological weathering attributable to poor health behaviors and adverse experiences, particularly those experienced in early life. For these reasons, we propose that telomere lengths may be a pivotal biomarker for measuring the heightened susceptibility to illness resulting from the cumulative exposure to acculturation to the US culture. This binational study used an Actor–Partner Interdependence Model to test if maternal acculturation to the US moderates the cross-sectional associations of telomere lengths with percentage of body fat (PBF) among Mexican women, among their children, and the intergenerational associations of mother and children telomere lengths with each other’s PBF. Low income Mexican child–mother dyads (n ​= ​108 dyads) were recruited to participate in this cross-sectional study in Mexico and the US. The pooled dataset included measurements of maternal acculturation to the US, mother and children’s salivary telomere lengths, PBF measured through bioelectrical impedance, and demographic characteristics. Results showed that the influences of maternal acculturation in the associations of telomere lengths with PBF were different for mothers and their children: Among mothers with higher maternal acculturation to the US, longer salivary telomere lengths were associated with lower PBF. In contrast, among mothers with lower maternal acculturation to the US, salivary telomere lengths were not associated with PBF. There were no significant associations between children’s salivary telomere lengths and PBF, and the null associations did not vary across different levels of maternal acculturation to the US. Future longitudinal studies are needed to determine whether acculturation to the US (experienced through immigration or remotely) influences the association of telomere length attrition with obesity risks among immigrant and non-immigrant Mexican children and adults.

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Women’s acculturation to the US modified the association of their TL with body fat.

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In mothers with high acculturation to the US, longer TL associated with higher body fat.

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In mothers with low acculturation to the US, TL were not associated with body fat.

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We found no evidence of intergenerational associations between TL and body fat.

Correlation between metabolic syndrome and relative telomere length shortening in HIV/AIDS patients on combined antiretroviral therapy

BACKGROUND

Components of the metabolic syndrome (MetS) play an important role in the accelerated aging process. Relative telomere length (RTL) is a marker of biological aging. The aim of our study was to determine RTL and its possible association with MetS and the components of MetS in HIV-infected patients treated with cART.

METHODS

We included 24 HIV-infected men, all Caucasians, with successful cART (<50 HIV-RNA copies/mL) and on stable cART for at least 24 months. The presence of MetS and its components was determined by the criteria prescribed by the International Diabetes Federation. RTL was determined by Real-Time PCR and ΔΔCt method. We performed a multiple linear regression modeling on log-transformed RTL (dependant variable) to evaluate which components of the metabolic syndrome as well as cART duration and cART type, had an impact on RTL.

RESULTS

Eleven (45.8%) patients had and 13 (54.2%) had not MetS. All patients, had an undetectable viral RNA and a relatively good immune status. The mean RTL was 0.62 ± 0.15 and 0.95 ± 0.36 in patients with and without MetS, respectively (p = 0.01). Multiple linear regression model showed no significant association between duration of cART, cART type and RTL (p = 0.2165, p = 0.8628, respectively). The same analysis showed that an increase in number of MetS components was associated with shorter telomere length (β = -0.4982, p = 0.042).

CONCLUSIONS

We showed for the first time association between RTL shortening in HIV-infected men with metabolic syndrome. Furthermore, our study also indicated that an increment of metabolic syndrome components is strongly associated with shorter telomere length.

Association of leukocyte telomere length with metabolic syndrome in type 2 diabetes mellitus

Background:

Leukocyte telomere length (LTL) has been revealed to be associated with aging-related diseases such as metabolic syndrome (MetS) and Type 2 diabetes mellitus (T2DM). We aimed to investigate the correlation of LTL with MetS and its components in T2DM patients in this cross-sectional study.

Materials and Methods:

A total of 344 T2DM patients were enrolled into this study. LTL was measured by Southern blot-based terminal restriction fragment length analysis. MetS was clinically defined by 2007 Chinese Guidelines on Prevention and Treatment of Dyslipidemia in Adults.

Results:

Of 344 T2DM patients, 53% had MetS. T2DM patients with MetS had significantly longer LTL than those without MetS (6451.95 ± 51.10 base pairs vs. 6076.13 ± 55.13 base pairs, P < 0.001), especially when T2DM patients had poor glycemic control (hemoglobin A1c ≥7%). Meanwhile, the trend of longer LTL was associated with the increased components of MetS in T2DM patient. Finally, LTL had a significant association with MetS (odds ratio [OR]: 2.096, 95% confidence interval [CI] 1.337–3.285, P = 0.001), low levels of high-density lipoprotein-cholesterol (HDL-C) (OR: 2.412, 95% CI 1.350–4.308, P = 0.003) in T2DM patients.

Conclusion:

T2DM patients with MetS had a significantly longer LTL than those without MetS. The longer LTL was especially evident in T2DM patients with poor glycemic control. Longer LTL was positively associated with MetS, particularly low levels of HDL-C in T2DM patients.

Demographic and developmental patterns in telomere length across adolescence

Telomere length is often used in studies of adults as a biomarker of cellular aging and an indicator of stress exposure. However, we know little about how telomeres change over time, particularly over the course of the important developmental period of adolescence. We use data on telomere length collected at two points in time spanning adolescence (Years 9 and 15) from the Fragile Families and Child Wellbeing Study to examine longitudinal patterns (n = 1,654) in telomere length. We find a quantitatively small but significant average lengthening in telomere length across adolescence and little evidence of associations between telomere length and pubertal development.

Relationship between Decreased Serum Superoxide Dismutase Activity and Metabolic Syndrome: Synergistic Mediating Role of Insulin Resistance and β-Cell Dysfunction

The interplays of cellular aging and oxidative stress (OS) markers form a complex network, which has been reported to be interrelated with numerous age-related and metabolic diseases, including metabolic syndrome (MS). However, given the multifactorial mechanisms of MS, several important confounders such as dietary factors and the reciprocal effect among these markers have not been considered and adjusted in previous investigations regarding the associations of cellular aging and OS markers with MS and its related metabolic abnormalities. To explicate this, we conducted a cross-sectional study among 533 Chinese adults. All the participants underwent a 75 g oral glucose tolerance test. Dietary data were collected via a 24-hour dietary recall and subsequently analyzed by a registered dietitian using nutrition calculation software. Clinical diagnosis of MS was made according to the revised National Cholesterol Education Program Adult Treatment Panel III criteria (2004) with waist circumference cutoff modified for an Asian population. The leukocyte telomere length, mitochondrial DNA copy number, 8-hydroxy-2-deoxyguanosine, superoxide dismutase (SOD) activity, and glutathione reductase were examined. SOD activity was significantly decreased in MS subjects (62.06 ± 16.89 U/mL vs. 56.25 ± 22.61 U/mL, P = 0.001) and exhibited a descending trend across sequential increase of MS component number (P for trend = 0.031). SOD activity is modestly correlated with glucose indicators and insulin sensitivity and β-cell function indices and was independently and negatively correlated with the level of triglyceride. An independent association between SOD activity and MS was observed after adjusting for metabolic indicators, dietary factors, cellular aging, and OS markers, as well as insulin sensitivity and β-cell function indices. However, the statistical significance of the association between SOD activity and MS was attenuated after adjusting for the Matsuda insulin sensitivity index (ISIM) and insulin secretion-sensitivity index-2 (ISSI-2), suggesting a possible mediating effect. Therefore, we conducted a mediation model analysis, which showed that decreased ISIM and ISSI-2 partially and synergistically mediated the contribution of decreased SOD activity to MS. In conclusion, decreased SOD activity is an independent predictor for increased risk of MS, and insulin resistance and β-cell dysfunction partially mediate the relationship between decreased SOD activity and MS.

Leukocyte-related parameters in older adults with metabolic syndrome

PURPOSE

We aimed to examine the association between leukocyte-related parameters and the risk of metabolic syndrome (MetS) in community-dwelling older Chinese adults, with a special focus on assessing the diagnostic ability of leukocyte-related parameters in detecting MetS and the potential interaction effect of sex in the leukocyte-MetS relationship.

METHODS

Study sample was from the Weitang Geriatric Diseases Study, which included 4579 individuals aged 60 years or above. MetS was diagnosed based on the Adult Treatment Panel III criteria. Leukocyte-related parameters were assessed using an automated hematology analyzer.

RESULTS

The adjusted odds ratio (95% confidence interval (CI)) of MetS for the highest quartile of leukocyte-related parameters (leukocyte, lymphocyte, neutrophil, monocyte, eosinophil, and basophil), when compared with the lowest quartile were 2.87 (2.30, 3.59), 2.69 (2.15, 3.36), 2.09 (1.67, 2.62), 2.12 (1.71, 2.64), 1.62 (1.31, 2.00), and 1.36 (1.11, 1.65), respectively. Adding leukocyte, lymphocyte, monocyte, and neutrophil to a model containing conventional risk factors improved risk prediction for MetS. Furthermore, significant interactions between leukocyte, monocyte, neutrophil, and sex on MetS were observed (all P value for interaction <0.01).

CONCLUSION

The numbers of total leukocytes, lymphocyte, monocyte, neutrophil, and eosinophil counts were elevated in older adults with MetS, suggesting that leukocyte-related parameters may be meaningful biomarkers for MetS. Adding leukocyte-related parameters to the conventional models increased the ability of predicting MetS among older adults. These parameters may be useful biomarkers for further risk appraisal of MetS in older adults.

The association of telomere length with substance use disorders: systematic review and meta-analysis protocol

BACKGROUND

The present protocol was designed for a systematic review and meta-analysis aimed at determining the association of telomere length with substance use disorders with the exclusion of nicotine addiction, and to identify potential moderators of the effect of telomere length. Such methodological information may provide guidance to improve the quality of future research on this important topic.

METHODS

Potential studies will be identified through electronic databases (PubMed/MEDLINE, EMBASE, PsycINFO, and Web of Science) up from inception onwards. The inclusion criteria will include published or unpublished observational studies (cohort, case-control, and cross-sectional studies) reporting telomere length in adult patients with substance use disorder compared with a control group. Non-human studies or other study designs such as reviews, case-only, family-based, and/or population studies with only healthy participants will be excluded, as well as those focused solely on nicotine addiction. The main outcome will be telomere length in adults with substance use disorder (primary) and, specifically, in those with alcohol use disorder (secondary). Two investigators will independently evaluate the preselected studies for possible inclusion and will extract data following a standardized protocol. Disagreements will be resolved by consensus. The risk of bias of all included studies will be assessed using the Newcastle-Ottawa Quality Assessment Scale for non-randomized studies. Data will be converted into standardized mean differences as effect size index, and random-effects models will be used for the meta-analysis. Cochran's Q statistic, I² index, and visual inspection of the forest plot will be used to verify study heterogeneity. Subgroup analyses and meta-regressions will be conducted to ascertain heterogeneity. Several sensitivity analyses will be conducted to address the influence of potential confounding factors. Publication bias will be examined using the "funnel plot" method with Duval and Tweedie's trim-and-fill method and Egger test.

DISCUSSION

This systematic review will assess the association of telomere length with substance use disorders aside from nicotine addiction.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42019119785.

Relative Telomere Length and Cardiovascular Risk Factors

(1) Background: Telomeres are repetitive DNA sequences located at the extremities of chromosomes that maintain genetic stability. Telomere biology is relevant to several human disorders and diseases, specifically cardiovascular disease. To better understand the link between cardiovascular disease and telomere length, we studied the effect of relative telomere length (RTL) on cardiovascular risk factors in a large population-based sample. (2) Methods: RTL was measured by a real-time quantitative polymerase chain reaction in subjects of the population-based Gutenberg Health Study (n = 4944). We then performed an association study of RTL with known cardiovascular risk factors of smoking status as well as systolic and diastolic blood pressure, body mass index (BMI), LDL cholesterol, HDL cholesterol, and triglycerides. (3) Results: A significant correlation was shown for RTL, with age as a quality control in our study (effect = −0.004, p = 3.2 × 10⁻⁴⁷). Analysis of the relation between RTL and cardiovascular risk factors showed a significant association of RTL in patients who were current smokers (effect = −0.016, p = 0.048). No significant associations with RTL were seen for cardiovascular risk factors of LDL cholesterol (p = 0.127), HDL cholesterol (p = 0.713), triglycerides (p = 0.359), smoking (p = 0.328), diastolic blood pressure (p = 0.615), systolic blood pressure (p = 0.949), or BMI (p = 0.903). In a subsequent analysis, we calculated the tertiles of RTL. No significant difference across RTL tertiles was detectable for BMI, blood pressure, lipid levels, or smoking status. Finally, we studied the association of RTL and cardiovascular risk factors stratified by tertiles of age. We found a significant association of RTL and LDL cholesterol in the oldest tertile of age (effect = 0.0004, p = 0.006). (4) Conclusions: We determined the association of relative telomere length and cardiovascular risk factors in a population setting. An association of telomere length with age, current smoking status, as well as with LDL cholesterol in the oldest tertile of age was found, whereas no associations were observed between telomere length and triglycerides, HDL cholesterol, blood pressure, or BMI.

Insulin treatment affects leukocyte telomere length in patients with type 2 diabetes: 6-year longitudinal study

OBJECTIVE

Many studies demonstrated a close relationship between type 2 diabetes mellitus (T2DM) and leukocyte telomere length (LTL). However, how the LTL changes in T2DM and what are the potential causal factors in it, particularly in patients during a long period treatment, have not been studied. Here we performed a longitudinal observation of LTL in trained T2DM patients during a 6-year follow-up and evaluated the possible risk factors that were associated with LTL alteration.

METHODS

Seventy-six patients with T2DM were enrolled in this 6-year longitudinal study. The enrolled patients had no severe complication and had never received insulin therapy by the time. Patients were scheduled to visit once every one or two months and their medication changes were recorded. The LTL at the time when patients were enrolled was used as baseline, which was compared with the LTL at 6 year. Multivariable linear regression and exact logistic regression model were adopted to identify independent predictors of telomere length change and telomere length shortening, respectively.

RESULTS

Sixty-four patients were successfully followed up. Although mean LTL decreased after 6 years, 30% (19/64) of patients demonstrated LTL lengthening and 70% (45/64) of patients demonstrated LTL shortening. Among them, 18 Patients received insulin treatment during the 6 years. Of these 18 patients, 16 patients showed decreased LTL and only two showed increased LTL. Linear regression analysis demonstrated that change in telomere length during the 6 years was associated inversely with insulin use (β-coefficients: -0.587, 95% CI: -0.198, -0.085, P < 0.001). Exact logistic regression analysis showed insulin use (OR: 17.355, 95% CI: 2.659, 35.627, P = 0.013) and LDL-C(OR: 3.493, 95% CI: 1.559, 10.063, P = 0.007)were independent predicts of telomere length shortening.

CONCLUSIONS

LTL may increase as well as decrease in T2DM who received antidiabetic treatment. Insulin use may accelerate telomere attrition. Insulin use and LDL-C can predict telomere shortening.

Association between prenatal particulate air pollution exposure and telomere length in cord blood: Effect modification by fetal sex

INTRODUCTION

In utero particulate matter exposure produces oxidative stress that impacts cellular processes that include telomere biology. Newborn telomere length is likely critical to an individual's telomere biology; reduction in this initial telomere setting may signal increased susceptibility to adverse outcomes later in life. We examined associations between prenatal particulate matter with diameter ≤2.5 µm (PM_2.5) and relative leukocyte telomere length (LTL) measured in cord blood using a data-driven approach to characterize sensitive windows of prenatal PM_2.5 effects and explore sex differences.

METHODS

Women who were residents of Mexico City and affiliated with the Mexican Social Security System were recruited during pregnancy (n = 423 for analyses). Mothers' prenatal exposure to PM_2.5 was estimated based on residence during pregnancy using a validated satellite-based spatio-temporally resolved prediction model. Leukocyte DNA was extracted from cord blood obtained at delivery. Duplex quantitative polymerase chain reaction was used to compare the relative amplification of the telomere repeat copy number to single gene (albumin) copy number. A distributed lag model incorporating weekly averages for PM_2.5 over gestation was used in order to explore sensitive windows. Sex-specific associations were examined using Bayesian distributed lag interaction models.

RESULTS

In models that included child's sex, mother's age at delivery, prenatal environmental tobacco smoke exposure, pre-pregnancy BMI, gestational age, birth season and assay batch, we found significant associations between higher PM_2.5 exposure during early pregnancy (4-9 weeks) and shorter LTL in cord blood. We also identified two more windows at 14-19 and 34-36 weeks in which increased PM_2.5 exposure was associated with longer LTL. In stratified analyses, the mean and cumulative associations between PM_2.5 and shortened LTL were stronger in girls when compared to boys.

CONCLUSIONS

Increased PM_2.5 during specific prenatal windows was associated with shorter LTL and longer LTL. PM_2.5 was more strongly associated with shortened LTL in girls when compared to boys. Understanding sex and temporal differences in response to air pollution may provide unique insight into mechanisms.

Elite athletes have longer telomeres than sedentary subjects: A meta-analysis

The aim of this meta-analysis was to investigate the effects of high levels of physical activity (in elite athletes) and sedentary lifestyle on telomere length. Our meta-analysis was carried out using the following electronic databases: PubMed, Cochrane Library, LILACS, Science Direct and EBSCO. After study selection, nine articles were included in our meta-analysis. All of the included subjects were elite athletes (with experience in national or international competitions) or sedentary subjects, which served as the control group. The analysis showed that elite athletes (n = 306) had longer telomeres (P = 0.001) compared with the control group (n = 322). The difference in the standardized means was 0.91 (95% CI = 0.43-1.33; I2 83.4% P value for heterogeneity = 0.001), favoring the athlete group. The analysis of the funnel plot did not detect any risk of publication bias in the studies that reported differences in means. Our results suggest that high level chronic physical training may provide protective effects on telomere length.

Additional Impact of Glucose Tolerance on Telomere Length in Persons With and Without Metabolic Syndrome in the Elderly Ukraine Population

Rationale: Association between different components of metabolic syndrome and the rate of age-related telomere shortening was reported repeatedly, although some findings are inconsistent across studies, suggesting the need for further research on the topic. In the present study, we examined relationships between different components of metabolic syndrome (MetS); glucose tolerance reflected in 2-h post-load plasma glucose (2hPG) levels and age on the leukocyte telomere length (LTL) in Ukraine population. Methods: The study was conducted on the 115 adult individuals residing in the Kyiv region (Ukraine). Among them, 79 were diagnosed with MetS according to the International Diabetes Federation definition. LTL were determined by a qPCR-based method. Multivariate logistic regression (MLR) and artificial neural networks (ANN) modeling were used for the analysis of the results. ROC-analysis was also performed to compare the predictively values of this models. Results: MetS was associated with a high (OR = 3.0 CI 1.3-6.7; p = 0.01) risk of having shorter telomeres that remained significant after adjusting for age, gender and 2hPG levels. Fasting plasma glucose (FPG) levels and other MetS components did not affect the magnitude of the relationship and did not reveal the independent influence of these factors. The level of 2hPG in turn, demonstrated a significant relationship (OR = 1.3 CI 1.0-1.6 per 1 mmol/l; p = 0.04) with LTL regardless of the presence of MetS. The non-linearity of the interactions between age, gender and 2hPG level was revealed by neural network modeling (AUC = 0.76 CI 0.68-0.84). Conclusion: Our study found that impaired glucose tolerance, but not FPG levels, affected the association between LTL and MetS, which may be also indicative for pathophysiological differences in these hyperglycemia categories. 2hPG levels can provide an opportunity for a more accurate diagnostics of MetS and for evaluating the rate of aging in patients with MetS. Further research, however, is needed to verify this assumption.

The association between longer relative leukocyte telomere length and risk of glioma is independent of the potentially confounding factors allergy, BMI, and smoking

PURPOSE

Previous studies have suggested an association between relative leukocyte telomere length (rLTL) and glioma risk. This association may be influenced by several factors, including allergies, BMI, and smoking. Previous studies have shown that individuals with asthma and allergy have shortened relative telomere length, and decreased risk of glioma. Though, the details and the interplay between rLTL, asthma and allergies, and glioma molecular phenotype is largely unknown.

METHODS

rLTL was measured by qPCR in a Swedish population-based glioma case-control cohort (421 cases and 671 controls). rLTL was related to glioma risk and health parameters associated with asthma and allergy, as well as molecular events in glioma including IDH1 mutation, 1p/19q co-deletion, and EGFR amplification.

RESULTS

Longer rLTL was associated with increased risk of glioma (OR = 1.16; 95% CI 1.02-1.31). Similar to previous reports, there was an inverse association between allergy and glioma risk. Specific, allergy symptoms including watery eyes was most strongly associated with glioma risk. High body mass index (BMI) a year prior diagnosis was significantly protective against glioma in our population. Adjusting for allergy, asthma, BMI, and smoking did not markedly change the association between longer rLTL and glioma risk. rLTL among cases was not associated with IDH1 mutation, 1p/19q co-deletion, or EGFR amplification, after adjusting for age at diagnosis and sex.

CONCLUSIONS

In this Swedish glioma case-control cohort, we identified that long rLTL increases the risk of glioma, an association not confounded by allergy, BMI, or smoking. This highlights the complex interplay of the immune system, rLTL and cancer risk.

TRF1 as a major contributor for telomeres' shortening in the context of obesity

Obesity is a prevalent multifactorial chronic disorder characterized by metabolic dysregulation. Sustained pro-oxidative mediators trigger harmful consequences that reflect at systemic level and contribute for the establishment of a premature senescent phenotype associated with macromolecular damage (DNA, protein, and lipids). Telomeres are structures that protect chromosome ends and are associated with a six-protein complex called the shelterin complex and subject to regulation. Under pro-oxidant conditions, telomere attrition and the altered expression of the shelterin proteins are central for the establishment of many pathophysiological conditions such as obesity. Thus, considering that individuals with obesity display a systemic oxidative stress profile that may compromise the telomeres length or its regulation, the aim of this study was to investigate telomere homeostasis in patients with obesity and explore broad/systemic associations with the expression of shelterin genes and the plasma redox state. We performed a cross-sectional study in 39 patients with obesity and 27 eutrophic subjects. Telomere length (T/S ratio) and gene expression of shelterin components were performed in peripheral blood mononuclear cells by qPCR. The oxidative damage (lipid peroxidation and protein carbonylation) and non-enzymatic antioxidant system (total radical-trapping antioxidant potential/reactivity, sulfhydryl and GSH content) were evaluated in plasma. Our results demonstrate that independently of comorbidities, individuals with obesity had significantly shorter telomeres, augmented expression of negative regulators of the shelterin complex, increased lipid peroxidation and higher oxidized protein levels associated with increased non-enzymatic antioxidant defenses. Principal component analysis revealed TRF1 as a major contributor for firstly telomeres shortening. In conclusion, our study is first showing a comprehensive analysis of telomeres in the context of obesity, associated with dysregulation of the shelterin components that was partially explained by TRF1 upregulation that could not be reversed by the observed adaptive non-enzymatic antioxidant response.

Longer telomeres in elderly schizophrenia are associated with long-term hospitalization in the Japanese population

Several previous studies have investigated an association between leukocyte telomere length (LTL) and schizophrenia (SCZ). However, results have been largely inconsistent, partially due to the relatively small sample sizes in each study and heterogeneity caused by various uncontrolled confounders (e.g., duration of illness or hospitalization, lifetime antipsychotic dose, and LTL assay methods). Here, we investigate the association of LTL with SCZ with the quantitative polymerase chain reaction method in independent cohorts consisting of 1241 patients with SCZ and 1042 controls (the largest independent sample in this field). Furthermore, we examined whether duration of hospitalization and lifetime antipsychotic dose had an effect on LTL in SCZ. In all samples, we observed significantly longer LTL in patients with SCZ relative to controls. In subgroup analyses, we observed that longer telomeres in SCZ were only visible in elderly patients and not in patients under 50 years old. Moreover, significantly longer LTL in elderly patients with SCZ was only specific to those with long-term hospitalization, but not outpatients or those with short-term hospitalization. This may be because the former received more appropriate lifestyle management. Meanwhile, lifetime antipsychotic dose had no effect on LTL. Our findings suggest that consideration of the effect of age and duration of hospitalization on LTL may improve our understanding of controversial results obtained in previous studies of telomeres in SCZ.

Diabetic Cardiomyopathy: Impact of Biological Sex on Disease Development and Molecular Signatures

Diabetic cardiomyopathy refers to a unique set of heart-specific pathological variables induced by hyperglycemia and insulin resistance. Given that cardiovascular disease (CVD) is the leading cause of death in the world, and type 2 diabetes incidence continues to rise, understanding the complex interplay between these two morbidities and developing novel therapeutic strategies is vital. Two hallmark characteristics specific to diabetic cardiomyopathy are diastolic dysfunction and cardiac structural mal-adaptations, arising from cardiac cellular responses to the complex toxicity induced by hyperglycemia with or without hyperinsulinemia. While type 2 diabetes is more prevalent in men compared to women, cardiovascular risk is higher in diabetic women than in diabetic men, suggesting that diabetic women take a steeper path to cardiomyopathy and heart failure. Accumulating evidence from randomized clinical trials indicate that although pre-menopausal women have lower risk of CVDs, compared to age-matched men, this advantage is lost in diabetic pre-menopausal women, which suggests estrogen availability does not protect from increased cardiovascular risk. Notably, few human studies have assessed molecular and cellular mechanisms regarding similarities and differences in the progression of diabetic cardiomyopathy in men versus women. Additionally, most pre-clinical rodent studies fail to include female animals, leaving a void in available data to truly understand the impact of biological sex differences in diabetes-induced dysfunction of cardiovascular cells. Elegant reviews in the past have discussed in detail the roles of estrogen-mediated signaling in cardiovascular protection, sex differences associated with telomerase activity in the heart, and cardiac responses to exercise. In this review, we focus on the emerging cellular and molecular markers that define sex differences in diabetic cardiomyopathy based on the recent clinical and pre-clinical evidence. We also discuss miR-208a, MED13, and AT2R, which may provide new therapeutic targets with hopes to develop novel treatment paradigms to treat diabetic cardiomyopathy uniquely between men and women.

Sub-fertile sperm cells exemplify telomere dysfunction

PURPOSE

The purpose of this study was to evaluate telomere homeostasis in sub-fertile compared to fertile human sperm.

METHODS

This observational, comparative study included 16 sub-fertile men who required intracytoplasmic sperm injection and 10 fertile men. At least 100 sperm cells from each participant were assessed. Main outcome measures were telomere length and telomere aggregates. Telomerase RNA component (TERC) copy number and telomere capture were assessed using fluorescence in situ hybridization technique and human telomerase reverse transcriptase (hTERT) using immunohistochemistry.

RESULTS

Clinical backgrounds were similar. The percentage of sperm cells with shorter telomeres was higher among the sub-fertile compared to the fertile participants (3.3 ± 3.1 vs. 0.6 ± 1.2%, respectively; P < 0.005). The percentage of cells with telomere aggregates was significantly higher in the sub-fertile group (15.12 ± 3.73 vs. 4.73 ± 3.73%; P < 0.005). TERC gene copy number was similar between groups. The percentage of cells that were positive for hTERT was lower in the sub-fertile group (3.81 ± 1.27 vs. 8.42 ± 1.80%; P < 0.005). Telomere capture rates were higher among the sub-fertile sperm cells (P < 0.005).

CONCLUSIONS

Sub-fertile sperm cells have short telomeres that are elongated by the alternative pathway of telomere capture. Dysfunctional telomeres may affect sperm fertilizability.