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Background: Numerous single nutrients have been suggested to be linked with leukocyte telomere length (LTL). However, data on nutrient patterns (NPs), particularly in Chinese population, are scarce. This study aimed to examine the relationship between nutrient-based dietary patterns and LTL, and the potential role of metabolic factors. Methods: Dietary data was obtained via 24-hour food recalls, and principal component analysis (PCA) was used to identify NPs. LTL was assessed using a real-time PCR assay. Multiple linear regression was conducted to determine the association between NPs and LTL. The potential role of metabolism among them was analyzed using mediation models. Results: A total of 779 individuals from northern China were included in this cross-sectional analysis. Five main nutrient patterns were identified. Adjusted linear regression showed that the "high sodium" pattern was inversely associated with LTL (B=-0.481(-0.549, -0.413), P < 0.05). The "high vitamin E-fat" pattern exhibited a positive correlation (B = 0.099(0.029, 0.170), P < 0.05), whereas the "high vitamin A-vitamin B2" pattern was negatively correlated with LTL (B=-0.120(-0.183, -0.057), P < 0.05), respectively. No significant associations were observed for the remaining nutrient patterns. The mediation model demonstrated that diastolic blood pressure and waist circumference could individually and collectively mediate the negative impact of the "high sodium" pattern on LTL (BDBP=-0.0173(-0.0333, -0.0041), BWC=-0.0075(-0.0186, -0.0004), Bjoint=-0.0033 (-0.0072, -0.0006), all P < 0.05). Moreover, glycosylated hemoglobin and non-high-density lipoprotein cholesterol mediate the relationship between the "high vitamin E-fat" pattern and LTL (BHbA1c=0.0170(0.0010,0.0347), Bnon-HDL-C= 0.0335 (0.0067, 0.0626), all P < 0.05), respectively. Conclusions: The "high sodium" and "high vitamin E-fat" nutrient patterns demonstrated negative and positive associations with LTL and metabolic indicators may play complex mediating roles in these relationships. [ABSTRACT FROM AUTHOR]

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

Telomere shortening, as seen with aging, can cause chromosomal instability and promote cancer progression. We investigated the association between circulating telomere length and overall and disease-free survival in a sub-cohort of patients with colorectal cancer. Baseline genomic DNA from blood leukocytes was extracted from N = 92 newly diagnosed stage I-IV patients with colorectal cancer enrolled at the ColoCare Study site in Heidelberg, Germany. Detailed information on clinicodemographic (including age) and lifestyle risk factors, and clinical outcomes (including recurrence and survival) was collected. Telomere length was measured in DNA using multiplex quantitative polymerase chain reaction. Kaplan Meier survival curves were generated comparing shorter to longer telomere lengths with log-rank testing. The mean T/S ratio for study patients was 0.5 (range: 0.3–0.9). Shorter telomeres were associated with older age at baseline. Patients with shorter telomeres experienced a worse overall and disease-free survival, although this association did not reach statistical significance. Kaplan-Meier survival curves for those with circulating telomere length below vs. above the median showed poorer overall (log-rank p = 0.31) and disease-free survival (long-rank p = 0.23). Our results suggest that individuals with shorter telomeres, as seen with aging, may experience a worse overall and disease-free survival after colorectal cancer diagnosis. Larger sample sizes with longer follow-up are needed to further evaluate telomere length as a prognostic biomarker in colorectal cancer progression. [ABSTRACT FROM AUTHOR]

Background and Aim: Alterations of glucose homeostasis can increase advanced glycation end products (AGEs) that exacerbate vascular inflammatory disease and may increase vascular senescence and aging. This study examined the relationships between carboxymethyl-lysine (CML) and soluble receptor for AGEs (sRAGE) with leukocyte telomere length (LTL) and mitochondrial DNA copy number (mtDNAcn), as cell aging biomarkers, in patients with established coronary artery disease (CAD).Methods and Results: We studied 459 patients with CAD further categorized as having normal glucose homeostasis (NG, n = 253), pre-diabetes (preT2D, n = 85), or diabetes (T2D, n = 121). All patients were followed up for the occurrence of major adverse cardiovascular events (MACEs). Plasma concentrations of sRAGE and CML were measured by ELISA. mtDNAcn and LTL were measured by qRT-PCR. CML levels were significantly higher in patients with preT2D (p < 0.007) or T2D (p < 0.003) compared with those with NG. mtDNAcn resulted lower in T2D vs preT2D (p = 0.04). At multivariate Cox proportional hazard analysis, short LTL (HR: 2.89; 95% CI: 1.11-10.1; p = 0.04) and high levels of sRAGE (HR: 2.20; 95% CI: 1.01-5.14; p = 0.04) were associated with an increased risk for MACEs in patients with preT2D and T2D, respectively. T2D patients with both short LTL and high sRAGE levels had the highest risk of MACEs (HR: 3.11; 95% CI: 1.11-9.92; p = 0.04).Conclusions: High levels of sRAGE and short LTL were associated with an increased risk of MACEs, especially in patients with diabetes, supporting the usefulness of both biomarkers of glycemic impairment and aging in predicting cardiovascular outcomes in patients with CAD. [ABSTRACT FROM AUTHOR]

Objective: Telomeres are protective sequences of DNA capping the ends of chromosomes that shorten over time. Leukocyte telomere length (LTL) is posited to reflect the replicative history of cells and general systemic aging of the organism. Chronic stress exposure leads to accelerated LTL shortening, which has been linked to increased susceptibility to and faster progression of aging-related diseases. This study examined longitudinal associations between LTL and experiences of racial discrimination, a qualitatively unique source of minority psychosocial stress, among African Americans. Method: Data are from 391 African Americans in the Coronary Artery Risk Development in Young Adults (CARDIA) Telomere Ancillary Study. We examined the number of domains in which racial discrimination was experienced in relation to LTL collected in Years 15 and 25 (Y15: 2000/2001; Y25: 2010/2011). Multivariable linear regression examined if racial discrimination was associated with LTL. Latent change score analysis (LCS) examined changes in racial discrimination and LTL in relation to one another. Results: Controlling for racial discrimination at Y15, multivariable linear regression analyses indicated that racial discrimination at Y25 was significantly associated with LTL at Y25. This relationship remained robust after adjusting for LTL at Y15 (b = −.019, p =.015). Consistent with this finding, LCS revealed that increases in experiences of racial discrimination were associated with faster 10-year LTL shortening (b = −.019, p =.015). Conclusions: This study adds to evidence that racial discrimination contributes to accelerated physiologic weathering and health declines among African Americans through its impact on biological systems, including via its effects on telomere attrition. [ABSTRACT FROM AUTHOR]

We analyze the leukocyte telomere length (LTL) and telomerase activity in patients with major depressive disorder (MDD) before and after treatment with selective serotonin reuptake inhibitors (SSRIs). Before treatment, there was a reduction in the LTLs and expression levels of the human telomerase reverse transcriptase (hTERT) in the patients with MDD compared with controls. However, after 24 weeks of treatment with SSRIs, there was a significant increase in the LTLs and the expression levels of hTERT , with values approaching those observed in the controls. We conclude that SSRI antidepressant therapy can directly influence the increased expression levels of hTERT in patients. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the effect of High Intensity Interval Training (HIIT) versus Aerobic Exercise (A-Ex) following 12 wks of training. Twenty-one Sprague Dawley rats (11 to 13 months) were assigned to 3 groups: (1) Control Group (no exercise); (2) A-Ex Group; and (3) HIIT Group. The A-Ex Group was submitted to treadmill exercise at a speed of 20 m⋅min-1 with a rest period of 90 sec every 5 min for 20 min 5 d⋅wk-1. The HIIT Group was submitted to treadmill exercise at a speed of 35 m⋅min-1 with a rest period of 90 sec every 5 min for 15 min 5 d⋅wk-1. At weeks 4 and 12, relative Leukocyte Telomere Length (LTL) was compared to week 4 of the Control Group using q-RT-PCR. It was shown that relative LTL in the A-Ex Group at week 4 and 12 was significantly longer compared to week 4 of the Control Group (P<0.05), but no significant difference in the HIIT Group compared to the Control Group (P>0.05). We concluded that 12 wks of aerobic and HIIT exercise both cause lengthening of relative LTL. Aerobic exercise has a better effect compared to HIIT in relation to changes in relative LTL. [ABSTRACT FROM AUTHOR]

Evidence has shown that leukocyte telomere length (LTL) at birth is related to the susceptibility to various diseases in later life and the setting of newborn LTL is influenced by the intrauterine environment. Perfluoroalkyl and polyfluoroalkyl substances (PFASs), as a kind of persistent organic pollutants, are commonly used in commercial and domestic applications and are capable of crossing the maternal-fetal barrier during pregnancy. We hypothesized that intrauterine exposure to PFASs may affect fetal LTL by increasing oxidative stress. To verify this hypothesis, LTL, concentrations of PFASs and reactive oxygen species (ROS) were measured in umbilical cord blood of 581 newborns from a prospective cohort. Our results showed that there were interactions between PFOS/PFDA and sex on LTL and ROS. The LTL was significantly shorter (0.926 ± 0.053 vs 0.945 ± 0.054, P  = .023 for PFOS; 0.919 ± 0.063 vs 0.940 ± 0.059, P  = .011 for PFDA) and the ROS levels were extremely higher (252.9 ± 60.5 [M] vs 233.5 ± 53.6 [M], P  = .031 for PFOS; 255.2 ± 62.9 [M] vs 232.9 ± 58.3 [M], P  = .011 for PFDA) in the female newborns whose PFOS or PFDA concentrations fell in the upmost quartile compared with those in the lowest quartile after adjusting for potential confounders. ROS levels were inversely associated with LTL in female newborns ( β  = −1.42 × 10 −4 , P  = .022). 13% of the effect of PFOS on female LTL was mediated through ROS approximately by the mediation analyses. However, in male newborns, no relationships among PFASs, ROS and LTL were observed. Our findings suggest a “programming” role of PFASs on fetal telomere biology system in females in intrauterine stage. [ABSTRACT FROM AUTHOR]

Indoor air pollution is an important environmental factor that contributes to the burden of various diseases. Long-term exposure to ambient air pollution is associated with telomere shortening. However, the association between chronic indoor air pollution from household fuel combustion and leukocyte telomere length has not been studied. In our study, 137 cancer-free non-smokers were recruited. Their exposure levels to indoor air pollution from 1985 to 2014 were assessed using a face-to-face interview questionnaire, and leukocyte telomere length (LTL) was measured using a monochrome multiplex quantitative PCR method. Accumulative exposure to solid fuel usage for cooking was negatively correlated with LTL. The LTL of residents who were exposed to solid fuel combustion for three decades (LTL = 0.70 ± 0.17) was significantly shorter than that of other populations. In addition, education and occupation were related to both exposure to solid fuel and LTL. Sociodemographic factors may play a mediating role in the correlation between leukocyte telomere length and environmental exposure to indoor air pollution. In conclusion, long-term exposure to indoor air pollution may cause LTL dysfunction. [ABSTRACT FROM AUTHOR]

Objective: A longitudinal study was conducted to examine sex-specific associations between changes in adiposity over a 10-year period, the FTO rs9939609 polymorphism, and leukocyte telomere length (LTL). Methods: A population-based cohort including 2128 middle-aged and older Korean men (n = 1087) and women (n = 1041) participated in a prospective study. Anthropometric measurements of weight, height, and waist and hip circumference were taken at baseline (from 2001 to 2003) and at the 10-year follow-up period (from 2011 to 2012). The FTO rs9939609 polymorphism was genotyped using DNA samples collected at baseline and LTL was assessed at the 10-year follow-up period. Multiple linear regression analysis was used with adjustments for age, baseline body mass index, and other potential confounders. Results: Presence of the FTO rs9939609 polymorphism risk allele was inversely associated with LTL (p < 0.01) in all participants, with a significant association seen only in women when the genders were modeled separately. Conversely, a significant inverse association between changes in waist circumference and LTL was found in men (p < 0.001) but not in women. No significant interaction between adiposity measures and the FTO polymorphism in association with LTL was identified for either sex. Conclusions: These data suggest that biological aging in men may be accelerated by increasing waist circumference, whereas in women, aging may be affected by genetic variations in FTO regardless of adiposity changes over time. [ABSTRACT FROM AUTHOR]

Compelling evidences indicate that relative telomere length (RTL) in peripheral blood leukocytes (PBLs) can predict the clinical outcome of several cancers. However, to date, the prognostic value of leukocyte RTL in gastric cancer (GC) patients has not been explored. In this study, relative telomere length (RTL) in peripheral blood leukocytes (PBLs) was measured using a real-time PCR-based method in a total of 693 GC patients receiving surgical resection. The prognostic value of leukocyte RTL was first explored in the training set (112 patients) using Kaplan–Meier and Cox proportional hazards regression analyses. Then an independent cohort of 581 patients was used as a validation set. To explore potential mechanism, we detected the immunophenotypes of peripheral blood mononuclear cells and plasma concentrations of several cytokines in GC patients. Patients with short RTL showed significantly worse overall survival (OS) and relapse-free survival (RFS) than those with long RTL in all patient sets. Furthermore, leukocyte RTL and TNM stage exhibited a notable joint effect in prognosis prediction. Integration of TNM stage and leukocyte RTL significantly improved the prognosis prediction efficacy for GC. In addition, we found that patients with short RTL had a higher CD4 + T cell percentage in PBMCs, CD19 + IL-10 + Breg percentage in B cells and plasma IL-10 concentration, indicating an enhanced immunosuppressive status with short leukocyte RTL. In conclusion, our study for the first time demonstrates that leukocyte RTL is an independent prognostic marker complementing TNM stage and associated with an immunosuppressive phenotype in the peripheral blood lymphocytes in GC patients. [ABSTRACT FROM AUTHOR]

Abstract: Background and aims: Leukocyte telomere length (LTL) is a novel marker of cardiovascular (CV) risk. The aim of the study was to investigate the major determinants of LTL in a healthy young population at very low CV risk. Methods and results: LTL was determined in 82 healthy subjects (49M/33F; age37 ± 9yrs), normotensive and not taking any medication with different family history of cardiovascular disease (CVD) (24yes/58no). Fasting blood samples were drawn in all subjects for the determination of lipid profile, high sensitive C-reactive protein, uric acid, Plasminogen Activator Inhibitor-1 (PAI-1), LTL and Endothelial Progenitor Cell (EPC) number. LTL was assessed with a specific real-time PCR reaction in leukocyte DNA samples. LTL resulted inversely correlated with family history of CVD (t = 2.70; p = 0.009), age (r = −0.238; p = 0.032), waist circumference (r = −0.256; p = 0.02), triglycerides (r = −0.218; p = 0.049), PAI-1 (r = −0.288; p = 0.009) and directly correlated with HDL-cholesterol (r = 0.316; p = 0.004) and EPC number (r = 0.358; p = 0.002). At a multivariate analysis, family history of CVD (p = 0.013), EPC count (p = 0.003), and HDL-cholesterol (p = 0.017) were independently associated with LTL (r = 0.62). Conclusion: LTL is independently associated to CV risk factors also in healthy young adults. [Copyright &y& Elsevier]