A biobehavioral perspective on telomere length and the exposome

Leukocyte telomere length and obesity in children and adolescents: A systematic review and meta-analysis

Background: Several studies have revealed the negative effects of adiposity on telomere length shortening. However, the results of the studies assessing the negative relationship between obesity and leukocyte telomere length (LTL) are not consistent. This systematic review and meta-analysis are aimed to pool the results of articles assessing the relationship between obesity and LTL among children and adolescents. Methods: To retrieve the related studies, four online databases including PubMed, Embase, ProQuest, and Scopus were searched until May 2022. Observational studies evaluating the relationship between obesity and LTL among apparently healthy children and adolescents (aged ≤18 years) were included in the study. We considered the studies that had reported a mean ± standard deviation of LTL. The random-effects model was used to assess the pooled weighted mean difference (WMD) and a 95% confidence interval (CI). Results: The search yielded seven studies from an initial 3,403 records identified. According to the results of seven articles with 4,546 participants, obesity was associated with LTL shortening among children and adolescents (WMD = -0.081; 95% CI: -0.137 to -0.026; p = 0.004; I2 = 99.9%). Also, no publication bias was observed. According to the results of subgrouping, significant results were only attributed to the studies conducted in Europe, with high quality scores, among overweight and obese adolescents, with a baseline LTL lower than 1, and performed in community-based school settings. Also, according to the subgrouping and meta-regression results, the obesity definition criteria and baseline LTL were the possible sources of between-study heterogeneity. Conclusion: We observed shorter LTL among overweight and obese children and adolescents. To obtain more reliable results, further longitudinal prospective studies with large sample sizes and more consistent and accurate definitions of obesity are required.

Updated Understanding of the Degenerative Disc Diseases - Causes Versus Effects - Treatments, Studies and Hypothesis

Background

In this review we survey medical treatments and research strategies, and we discuss why they have failed to cure degenerative disc diseases or even slow down the degenerative process.

Objective

We seek to stimulate discussion with respect to changing the medical paradigm associated with treatments and research applied to degenerative disc diseases.

Method Proposal

We summarize a Biological Transformation therapy for curing chronic inflammations and degenerative disc diseases, as was previously described in the book Biological Transformations controlled by the Mind Volume 1.

Preliminary Studies

A single-patient case study is presented that documents complete recovery from an advanced lumbar bilateral discopathy and long-term hypertrophic chronic rhinitis by application of the method proposed.

Conclusion

Biological transformations controlled by the mind can be applied by men and women in order to improve their quality of life and cure degenerative disc diseases and chronic inflammations illnesses.

Updated Understanding of Cancer as a Metabolic and Telomere-Driven Disease, and Proposal for Complex Personalized Treatment, a Hypothesis

In this review, we propose a holistic approach to understanding cancer as a metabolic disease. Our search for relevant studies in medical databases concludes that cancer cells do not evolve directly from normal healthy cells. We hypothesize that aberrant DNA damage accumulates over time-avoiding the natural DNA controls that otherwise repair or replace the rapidly replicating cells. DNA damage starts to accumulate in non-replicating cells, leading to senescence and aging. DNA damage is linked with genetic and epigenetic factors, but the development of cancer is favored by telomerase activity. Evidence indicates that telomere length is affected by chronic inflammations, alterations of mitochondrial DNA, and various environmental factors. Emotional stress also influences telomere length. Chronic inflammation can cause oxidative DNA damage. Oxidative stress, in turn, can trigger mitochondrial changes, which ultimately alter nuclear gene expression. This vicious cycle has led several scientists to view cancer as a metabolic disease. We have proposed complex personalized treatments that seek to correct multiple changes simultaneously using a psychological approach to reduce chronic stress, immune checkpoint therapy with reduced doses of chemo and radiotherapy, minimal surgical intervention, if any, and mitochondrial metabolic reprogramming protocols supplemented by intermittent fasting and personalized dietary plans without interfering with the other therapies.

The risk of developing cardiovascular disease is increased for patients with prostate cancer who are pharmaceutically treated for depression

OBJECTIVE

To examine the associations between pharmaceutically treated anxiety and depression and incident cardiovascular disease (CVD) among 1-year prostate cancer survivors.

PATIENTS AND METHODS

A registry-based cohort study design was used to describe the risk of incident CVD in adult 1-year prostate cancer survivors without a history of CVD. Patients with prostate cancer diagnosed between 1999 and 2011 were selected from the Netherlands Cancer Registry. Drug dispenses were retrieved from the PHARMO Database Network and were used as proxy for CVD, anxiety, and depression. Data were analysed using Cox regression analysis to examine the risk associations between pharmaceutically treated anxiety and depression entered as a time-varying predictor with incident CVD in 1-year prostate cancer survivors, while controlling for age, traditional CVD risk factors, and clinical characteristics.

RESULTS

Of the 5262 prostate cancer survivors, 327 (6%) developed CVD during the 13-year follow-up period. Prostate cancer survivors who were pharmaceutically treated for depression had an increased risk of incident CVD after full adjustment compared to prostate cancer survivors who were not pharmaceutically treated for depression (hazard ratio [HR] 1.51, 95% confidence interval [CI] 1.06-2.15). The increased risk of incident CVD amongst those pharmaceutically treated for depression compared to those who were not pharmaceutically treated for depression, was only valid among: prostate cancer survivors who were aged ≤65 years (HR 2.91; 95% CI 1.52-5.55); those who were not treated with radiotherapy (HR 1.63; 95% CI 1.01-2.65); those who were treated with hormones (HR 1.76; 95% CI 1.09-2.85); those who were not operated upon (HR 1.55; 95% CI 1.07-2.25); and those with tumour stage III (HR 2.21; 95% CI 1.03-4.74) and stage IV (HR 2.47; 95% CI 1.03-5.89).

CONCLUSION

Patients with prostate cancer who were pharmaceutically treated for depression had a 51% increased risk of incident CVD after adjustment for anxiety, age, traditional CVD risk factors, and clinical characteristics. The results emphasise the need to pay attention to (pharmaceutically treated) depressed patients with prostate cancer prior to deciding on prostate cancer treatment and for a timely detection and treatment of CVD.

Relative telomere length and gene expression of shelterin complex proteins among vinyl chloride monomer-exposed workers in China

Vinyl chloride monomer (VCM) is a confirmed carcinogen. The effects of VCM on telomeres and the gene expression of telomere complex proteins, shelterin, have not been well studied but could be of potential relevance to the carcinogenic mechanism of VCM and the health surveillance of VCM-exposed workers. A group of 241 VCM-exposed workers and 101 internal controls from the same plant in Shandong, China were recruited and quantitative polymerase chain reaction was preformed to measure relative telomere length (RTL) and gene expression of shelterin proteins. VCM cumulative exposure dose (CED) was estimated for the exposed workers. The differences in RTL and gene expression between groups were compared by Wald test fitted with robust regression. Shorter RTL was observed in VCM-exposed workers than in the controls (P < 0.001) and was related to CED of VCM. Shortened RTL was also significantly related to increasing age (P = 0.012) and high blood pressure (P = 0.056). Levels of gene expression of shelterin components in exposed workers were all lower than in controls except increased TIN2 expression, and the gene expression differences in TIN2 and POT1 among exposed and control groups were significant (P = 0.014 for TIN2 and P < 0.001 for POT1, respectively). VCM exposure is found associated with altered telomere length and gene expression of shelterin components. This provides new insights into the potential carcinogenic mechanisms of VCM and could be helpful for the health surveillance for VCM-exposed workers. Environ. Mol. Mutagen. 60:361-367, 2019. © 2018 Wiley Periodicals, Inc.

Incidence of cardiovascular disease up to 13 year after cancer diagnosis: A matched cohort study among 32 757 cancer survivors

We examined the incidence of cardiovascular disease (CVD) among 32 757 cancer survivors and age-, gender-, and geographically matched cancer-free controls during a follow-up period of 1-13 years, and explored whetherCVD incidence differed by received cancer treatment, traditional cardiovascular risk factors, age, or gender. Adult 1-year cancer survivors without a history ofCVD diagnosed with breast (n = 6762), prostate (n = 4504), non-Hodgkin (n = 1553), Hodgkin (n = 173), lung and trachea (n = 2661), basal cell carcinoma (BCC; n = 12 476), and colorectal (n = 4628) cancer during 1999-2011 were selected from the Netherlands Cancer Registry and matched to cancer-free controls without a history ofCVD. Drug dispenses and hospitalizations from thePHARMO Database Network were used as proxy forCVD. Data were analyzed using Cox regression analyses. Prostate (HR: 1.17; 95%CI: 1.01-1.35) and lung and trachea (HR: 1.48; 95%CI: 1.10-1.97) cancer survivors had an increased risk for developingCVD compared to cancer-free controls. This increased risk among lung and trachea cancer survivors remained statistically significant after including traditional cardiovascular risk factors and cancer treatment information (HR: 1.41; 95%CI: 1.06-1.89). Among prostate cancer survivors, the increased risk of incidentCVD was limited to those who received hormones and those without traditional cardiovascular risk factors. Breast, non-Hodgkin,BCC, and colorectal cancer survivors showed no increasedCVD risk compared to cancer-free controls. There was an increased risk of incidentCVD among prostate, and lung and trachea cancer survivors compared to age-, gender- and geographically matched cancer-free controls. Studies including longer follow-up periods are warranted to examine whether cancer survivors are at increased risk of long-term incidentCVD.

Leukocyte telomere length and personality: associations with the Big Five and Type D personality traits

Backgrounds Accelerated cellular ageing, which can be examined by telomere length (TL), may be an overarching mechanism underlying the association between personality and adverse health outcomes. This 6-year longitudinal study examined the relation between personality and leukocyte telomere length (LTL) across time among adults with a wide age-range.

METHODS

Data from the Netherlands Study of Depression and Anxiety were used and included patients with a depression and/or anxiety disorder and healthy controls. Overall, 2936 persons (18-65 years, 66% female) had data on LTL at baseline and 1883 persons had LTL at 6-year follow-up. The Big Five personality traits (neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness) and Type D personality were assessed.

RESULTS

Neuroticism was negatively (B = -2.11, p = 0.03) and agreeableness was positively (B = 3.84, p = 0.03) related to LTL measured across two time points, which became just non-significant after adjusting for somatic health, lifestyle factors, and recent life stress (B = -1.99, p = 0.06; and B = 3.01, p = 0.10). Type D personality was negatively (B = -50.16, p < 0.01) related to LTL across two time points, which still remained statistically significant after full adjustment (B = -47.37, p = 0.01). Associations did not differ by age, gender, and current psychiatric status.

CONCLUSIONS

The Big Five traits high neuroticism and low agreeableness, and Type D personality were associated with shorter LTL measured across a 6-year period. Associations with the Big Five traits became non-significant after controlling for somatic health, lifestyle factors, and recent life stress, yet similar trends were observed. Type D personality remained independently associated with shorter LTL after full adjustment.

Why are there associations between telomere length and behaviour?

Individual differences in telomere length are associated with individual differences in behaviour in humans and birds. Within the human epidemiological literature this association is assumed to result from specific behaviour patterns causing changes in telomere dynamics. We argue that selective adoption-the hypothesis that individuals with short telomeres are more likely to adopt specific behaviours-is an alternative worthy of consideration. Selective adoption could occur either because telomere length directly affects behaviour or because behaviour and telomere length are both affected by a third variable, such as exposure to early-life adversity. We present differential predictions of the causation and selective adoption hypotheses and describe how these could be tested with longitudinal data on telomere length. Crucially, if behaviour is causal then it should be associated with differential rates of telomere attrition. Using smoking behaviour as an example, we show that the evidence that smoking accelerates the rate of telomere attrition within individuals is currently weak. We conclude that the selective adoption hypothesis for the association between behaviour and telomere length is both mechanistically plausible and, if anything, more compatible with existing empirical evidence than the hypothesis that behaviour is causal.This article is part of the theme issue 'Understanding diversity in telomere dynamics'.

Acculturation Predicts Negative Affect and Shortened Telomere Length

Chronic stress may accelerate cellular aging. Telomeres, protective "caps" at the end of chromosomes, modulate cellular aging and may be good biomarkers for the effects of chronic stress, including that associated with acculturation. The purpose of this analysis was to examine telomere length (TL) in acculturating Hispanic Mexican American women and to determine the associations among TL, acculturation, and psychological factors. As part of a larger cross-sectional study of 516 pregnant Hispanic Mexican American women, we analyzed DNA in blood samples ( N = 56) collected at 22-24 weeks gestation for TL as an exploratory measure using monochrome multiplex quantitative telomere polymerase chain reaction (PCR). We measured acculturation with the Acculturation Rating Scale for Mexican Americans, depression with the Beck Depression Inventory, discrimination with the Experiences of Discrimination Scale, and stress with the Perceived Stress Scale. TL was negatively moderately correlated with two variables of acculturation: Anglo orientation and greater acculturation-level scores. We combined these scores for a latent variable, acculturation, and we combined depression, stress, and discrimination scores in another latent variable, "negative affectivity." Acculturation and negative affectivity were bidirectionally correlated. Acculturation significantly negatively predicted TL. Using structural equation modeling, we found the model had an excellent fit with the root mean square error of approximation estimate = .0001, comparative fit index = 1.0, Tucker-Lewis index = 1.0, and standardized root mean square residual = .05. The negative effects of acculturation on the health of Hispanic women have been previously demonstrated. Findings from this analysis suggest a link between acculturation and TL, which may indicate accelerated cellular aging associated with overall poor health outcomes.