Shorter Newborn Telomere Length Research Articles

Prenatal exposure to environmental heavy metals and newborn telomere length: A systematic review and meta-analysis

Exposure to environmental heavy metals is associated with telomere length (TL) alteration. Available information regarding the effect of prenatal exposure to environmental pollutants on newborn TL is controversial. The aim of this study is to systematically review and conduct a meta-analysis of the existing epidemiological studies on the associations between prenatal metal exposure and newborn TL. A comprehensive literature search was performed using the online databases of PubMed, Web of Science, and ScienceDirect from their inception to December 1, 2023. Thirteen eligible studies were included from the overall initial identification of 3559 records. The effect size was expressed as standardized beta coefficients with 95% confidence intervals (CIs) by the restricted maximum-likelihood approach with a weighted random-effects model. Prenatal exposure to environmental heavy metals was associated with a shorter newborn TL (standardized beta = −0.04; 95% CI: −0.08, 0.00; p = 0.05). Subgroup analysis showed that prenatal exposure to cadmium was significantly, negatively associated with TL in newborns (standardized beta = −0.05; 95% CI: −0.10, −0.01; p = 0.021). Heavy metal exposure during the third trimester was significantly associated with a shorter TL in newborns (standardized beta = −0.05; 95% CI: −0.11, −0.01; p = 0.045). No significant association was found between the newborn's sex and exposure sample type. This study provides evidence for the negative effect of prenatal exposure to heavy metals on newborn TL. In particular, cadmium exposure and exposure during the third trimester of pregnancy are critical factors associated with heavy metal-induced TL shortening.

Associations between prenatal multiple plasma metal exposure and newborn telomere length: Effect modification by maternal age and infant sex

Exposure to metals during pregnancy may affect maternal and infant health. However, studies on the combined effects of metals on the telomere length (TL) of newborns are limited. A prospective cohort study was conducted among 1313 mother–newborn pairs in the Guangxi Zhuang Birth Cohort. The concentrations of metals in maternal plasma during the first trimester were measured using inductively coupled plasma–mass spectrometry. We explored the associations between nine plasma metals and newborn TL using generalized linear models (GLMs), principal component analysis (PCA), quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR). The GLMs revealed the inverse association between plasma arsenic (percent change, −5.56%; 95% CI: -7.69%, −3.38%) and barium concentrations (−9.84%; 95% CI: -13.81%, −5.68%) and newborn TL. Lead levels were related to significant decreases in newborn TL only in females. The PCA revealed a negative association between the PC3 and newborn TL (−4.52%; 95% CI: -6.34%, −2.68%). In the BKMR, the joint effect of metals was negatively associated with newborn TL. Qgcomp indicated that each one-tertile increase in metal mixture levels was associated with shorter newborn TL (−9.39%; 95% CI: -14.32%, −4.18%). The single and joint effects of multiple metals were more pronounced among pregnant women carrying female fetuses and among pregnant women <28 years of age. The finding suggests that prenatal exposure to arsenic, barium, antimony, and lead and mixed metals may shorten newborn TLs. The relationship between metal exposures and newborn TL may exhibit heterogeneities according to infant sex and maternal age.

Maternal overweight but not paternal overweight before pregnancy is associated with shorter newborn telomere length: evidence from Guangxi Zhuang birth cohort in China

BackgroundTelomere length (TL) is variable at birth and is inversely associated with body mass index (BMI) in adulthood. A growing number of evidences suggested that a higher maternal pre-pregnancy BMI results in adverse offspring health outcomes, especially shorter newborn TL. However, a newborn’s genetic endowment is equally derived from both parents, the association between parental pre-pregnancy BMI and newborn TL has been rarely discussed. We aimed to determine the association between parental pre-pregnancy BMI and newborn TL.MethodsA total of 1082 parent-newborn pairs were recruited from the Guangxi Zhuang Birth Cohort (GZBC). TL in cord blood was measured using quantitative real-time polymerase chain reaction (qPCR) and expressed as the ratio of telomere copy number to single-copy gene number (T/S). A series of linear regressions were performed to assess the associations between parental pre-pregnancy BMI and newborn TL.ResultsMothers who were overweight before pregnancy had significantly shorter cord blood telomere length in their newborns than those who were normal weight before pregnancy [percentage change: − 7.96% (95% CI: − 14.49 to − 0.69%; P = 0.032)]. Further analysis of the combined effects of parental weight status on newborn TL showed that TL was significantly shortened among newborns whose mothers were overweight and fathers were of healthy weight when compared with those whose mothers and fathers were both of normal weight [percentage change: − 8.38% (95% CI: − 15.47 to − 0.92%; P = 0.028)]. Subgroup analysis indicated these effects were more pronounced among male newborns and those whose paternal age < 31 years or maternal age ≥ 28 years at delivery.ConclusionsMaternal pre-pregnancy overweight, but not paternal pre-pregnancy overweight is associated with shorter newborn TL. Weight control in reproductive women and effective healthy weight management before pregnancy may be of particular benefit for improving longevity and life quality of offspring.

The association of maternal psychosocial stress with newborn telomere length.

BackgroundTelomere length in early life predicts later length, and shortened telomere length among adults and children has been linked to increased risk of chronic disease and mortality. Maternal stress during pregnancy may impact telomere length of the newborn.MethodsIn a diverse cohort of 355 pregnant women receiving prenatal and delivery care services at two hospitals in San Francisco, California, we investigated the relationship between self-reported maternal psychosocial stressors during the 2nd trimester of pregnancy and telomere length (T/S ratio) in newborn umbilical cord blood leukocytes. We examined financial strain, food insecurity, high job strain, poor neighborhood quality, low standing in one’s community, experience of stressful/traumatic life events, caregiving for a dependent family member, perceived stress, and unplanned pregnancy. We used linear regression and Targeted Minimum Loss-Based Estimation (TMLE) to evaluate the change in the T/S ratio associated with exposure to each stressor controlling for maternal age, education, parity, race/ethnicity, and delivery hospital.ResultsIn TMLE analyses, low community standing (-0.09; 95% confidence interval [CI]-0.19 to 0.00) and perceived stress (-0.07; 95% CI -0.15 to 0.021 was marginally associated with shorter newborn telomere length, but the associations were not significant after adjusting for multiple comparisons. All linear regression estimates were not statistically significant. Our results also suggest that the association between some maternal stressors and newborn telomere length varies by race/ethnicity and infant sex.ConclusionsThis study is the first to examine the joint effect of multiple stressors during pregnancy on newborn TL using a flexible modeling approach.

Earlier maternal menarche is associated with shorter newborn telomere length.

The aim of our study was to investigate the relationship between maternal age at menarche and newborn telomere length which has been linked to lifespan and many age-related diseases. There were 734 mother-newborn pairs recruited from Wuhan Children's Hospital Wuhan, Hubei Province, China. Age at menarche was self-reported and categorized into three groups (≤ 12years, 13years, and ≥ 14years). Telomere length in cord blood was measured using quantitative real-time polymerase chain reaction and expressed as the ratio of telomere copy number to single-copy gene number (T/S). The mean age at menarche of 734 mothers was 13.1 (± 1.1) years and the adjusted geometric means in the T/S of newborn telomeres in the three groups were 0.693, 0.721, and 0.748 respectively. Earlier age at menarche (≤ 12years), compared with later age at menarche ≥ 14years, was significantly associated with 7.32% (95% CI - 13.70%, - 0.23%) shorter telomere length in offspring after adjusting for potential confounders.Conclusion: Mothers with earlier age at menarche were more likely to give birth newborn with shorter telomere length. Our study provides evidences for the effect of earlier menarche on fetal telomere programming in offspring. What is Known: • Newborn telomere length is considered an indicator of lifespan and health outcomes in later life. • The adverse effects of earlier menarche age to their offspring have been found, but its relationship with newborn telomere length has not been assessed before. What is New: • This is the first study to explore the relationship of maternal menarche age with newborn telomere length. • We provided primary evidence that earlier maternal age at menarche was associated with shorter newborn telomere length.

Prenatal second-hand smoke exposure and newborn telomere length

Cigarette smoking is associated with shorter telomere lengths in adults, but evidence on the effect of prenatal tobacco exposure is limited. We aimed to investigate the association between prenatal second-hand smoke exposure and newborn telomere length. We recruited 762 mother-newborn pairs from Wuhan Children's Hospital (Wuhan Maternal and Child Healthcare Hospital) between November 2013 and March 2015. Information on second-hand smoke exposure was obtained via questionnaires. Relative telomere length was measured in DNA extracted from umbilical cord blood. We used linear regression to assess the associations between prenatal second-hand smoke exposure and newborn telomere length. In the fully adjusted model, prenatal second-hand smoke exposure was associated with 9.7% shorter newborn telomere length (percent difference: -9.7%; 95% confidence interval (CI): -15.0, -4.0). The estimate for boys was lower (percent difference: -10.9%; 95% CI: -18.6, -2.5) than that for girls (percent difference: -8.5%; 95% CI: -15.8, -0.5), but the interaction term between newborn sex and prenatal second-hand smoke was not significant (P = 0.751). This study demonstrated that prenatal second-hand smoke exposure may be a preventable risk factor for accelerated biological aging in the intrauterine stage, and further suggested possible sex differences in the susceptibility to prenatal second-hand smoke.

Maternal pro-inflammatory state during pregnancy and newborn leukocyte telomere length: A prospective investigation

IntroductionTelomere biology plays a fundamental role in maintaining the integrity of the genome and cell, and shortened telomeres have been linked to several age-related diseases. The initial (newborn) telomere length (TL) represents a critically important feature of the telomere biology system. Exposure to a variety of adverse prenatal conditions such as maternal stress, suboptimal diet, obesity, and obstetric complications, is associated with shorter offspring TL at birth and in adult life. Many, if not all, of these exposures are believed to have an inflammatory component. In this context, stress-related immunological processes during pregnancy may constitute a potential additional biological pathway because they can affect telomere length and telomerase activity via transcriptions factors such as cyclic adenosine monophosphate-dependent transcription factor (ATF7) and nuclear factor-kappa B (NF-κB). Thus, in the present study we examined the hypothesis that maternal pro-inflammatory state across pregnancy, operationalized as the balance between tumor necrosis factor (TNF)-α, a major pro-inflammatory cytokine, and interleukin-10 (IL-10), the major anti-inflammatory cytokine, is associated with newborn leukocyte telomere length (LTL) at birth. Methods and MaterialsParticipants were healthy women (N = 112) recruited in early pregnancy. Concentrations of TNF- α and IL-10 were quantified in early, mid and late pregnancy from maternal blood samples. Telomere length was assessed in newborn blood samples soon after birth. ResultsAfter adjusting for maternal age, maternal pre-pregnancy BMI, birth weight percentile, and infant sex, a higher mean TNF-α/IL-10 ratio across pregnancy was significantly associated with shorter newborn TL (β = −.205, p = .030). Newborn TL was, on average, 10% shorter in offspring of women in the upper compared to lower quartile of the TNF-α/IL-10 ratio during pregnancy. DiscussionThese findings provide new evidence in humans for a potential “programming” mechanism linking maternal systemic pro-inflammatory processes during pregnancy with the initial (newborn) setting of her offspring’s telomere system.

Sex differences in effects of maternal risk and protective factors in childhood and pregnancy on newborn telomere length

Little research has examined determinants of newborn telomere length, a potential biomarker of lifetime disease risk impacted by prenatal exposures. No study has examined whether maternal exposures in childhood influence newborn telomere length or whether there are sex differences in the maternal factors that influence newborn telomere length. We tested whether a range of maternal risk and protective factors in childhood and pregnancy were associated with newborn telomere length among 151 sociodemographically diverse mother-infant dyads. We further examined whether the pattern of associations differed by infant sex. Newborn telomere length was assessed from cord blood collected at birth. Risk/protective factors included maternal health (smoking, body mass index), socioeconomic status (education, income), stress exposures, and mental health (depressive and posttraumatic stress disorder symptoms) in pregnancy as well as maternal experiences of abuse (physical, emotional, sexual) and familial emotional support in childhood. When examined within the whole sample, only maternal smoking in pregnancy and familial emotional support in childhood emerged as significant predictors of newborn telomere length. Male and female newborns differed in their pattern of associations between the predictors and telomere length. Among males, maternal smoking, higher body mass index, and elevated depressive symptoms in pregnancy and maternal sexual abuse in childhood were associated with shorter newborn telomere length; higher maternal educational attainment and household income in pregnancy and greater maternal familial emotional support in childhood were associated with longer newborn telomere length. Together, these factors accounted for 34% of the variance in male newborn telomere length. None of the risk/protective factors were associated with female newborn telomere length. The results suggest that male fetuses are particularly susceptible to maternal exposure effects on newborn telomere length. These findings have implications for elucidating mechanisms contributing to sex disparities in health.

Glucocorticoids in hair as biomarkers of traumatization in healthy individuals and PTSD patients

Rationale/statement of the problemSubstantial evidence suggests conditions in intrauterine life may play a critical role in subsequent health and disease susceptibility related outcomes (i.e., the concept of fetal or developmental programming of health and disease). The elucidation of biological mechanisms underlying these effects is an area of active investigation. We suggest that telomere biology may represent a novel mechanism underlying the effects of a disparate set of suboptimal intrauterine exposures on various health and disease risk phenotypes. From an evolutionary-developmental perspective, energy substrate availability (i.e., nutrition) and challenges that have the potential to impact the structural or functional integrity and survival of the organism (i.e., stress) likely represent the most important environmental considerations underlying natural selection and developmental plasticity. Maternal stress and nutrition in pregnancy therefore represent attractive candidate processes in the context of fetal programming of telomere biology. Our previous work has established an important role for prenatal stress and stress-related processes in adult telomere biologyMethodsIn two longitudinal birth cohorts, stress- and nutrition-related processes were assessed during pregnancy and telomere length (TL) was subsequently measured in newborns (cord blood) and infants (buccal cells).Results(1) Among the nutrition-related factors, maternal lower folate levels (an essential methyl donor) and higher triglyceride concentrations in early pregnancy were significantly and independently associated with shorter newborn TL. (2) Among psychosocial stress-related measures, higher maternal pregnancy-specific stress was associated with shorter newborn TL. (3) Maternal estrogen (E3) levels during early pregnancy were associated with longer infant TL.ConclusionTaken together, our findings provide the first evidence in humans that maternal nutrition and stress-related processes during pregnancy may exert a programming effect on the newborn and infant telomere biology system. In utero telomere biology represents a potential molecular mechanism whereby different exposures in this critical developmental period before birth could impact subsequent health and disease susceptibility related outcomes over the life span, including aging and longevity

Prenatal programming of newborn and infant telomere length

Rationale / statement of the problem: Substantial evidence suggests conditions in intrauterine life may play a critical role in subsequent health and disease susceptibility related outcomes (i.e., the concept of fetal or developmental programming of health and disease). The elucidation of biological mechanisms underlying these effects is an area of active investigation. We suggest that telomere biology may represent a novel mechanism underlying the effects of a disparate set of suboptimal intrauterine exposures on various health and disease risk phenotypes. From an evolutionary-developmental perspective, energy substrate availability (i.e., nutrition) and challenges that have the potential to impact the structural or functional integrity and survival of the organism (i.e., stress) likely represent the most important environmental considerations underlying natural selection and developmental plasticity. Maternal stress and nutrition in pregnancy therefore represent attractive candidate processes in the context of fetal programming of telomere biology. Our previous work has established an important role for prenatal stress and stress-related processes in adult telomere biologyMethods: In two longitudinal birth cohorts, stress- and nutrition-related processes were assessed during pregnancy and telomere length (TL) was subsequently measured in newborns (cord blood) and infants (buccal cells).Results: (1) Among the nutrition-related factors, maternal lower folate levels (an essential methyl donor) and higher triglyceride concentrations in early pregnancy were significantly and independently associated with shorter newborn TL. (2) Among psychosocial stress-related measures, higher maternal pregnancy-specific stress was associated with shorter newborn TL. (3) Maternal estrogen (E3) levels during early pregnancy were associated with longer infant TL.Conclusion: Taken together, our findings provide the first evidence in humans that maternal nutrition and stress-related processes during pregnancy may exert a programming effect on the newborn and infant telomere biology system. In utero telomere biology represents a potential molecular mechanism whereby different exposures in this critical developmental period before birth could impact subsequent health and disease susceptibility related outcomes over the life span, including aging and longevity