The variable associations between PFASs and biological aging by sex and reproductive stage in NHANES 1999-2018

Moderate BMI accumulation modified associations between blood benzene, toluene, ethylbenzene and xylene (BTEX) and phenotypic aging: mediating roles of inflammation and oxidative stress

The associations between blood benzene, toluene, ethylbenzene, and xylenes (BTEX) and biological aging among general adults remain elusive. The present study comprised 5780 participants from the National Health and Nutrition Examination Survey 1999-2010. A novel measure of biological aging, phenotypic age acceleration (PhenoAge.Accel), derived from biochemical markers was calculated. Weighted generalized linear regression and weighted quantile sum regression (WQS) were utilized to assess the associations between BTEX components and mixed exposure, and PhenoAge.Accel. The mediating roles of systemic immune-inflammation index (SII) and oxidative stress indicators (serum bilirubin and gamma-glutamyl transferase), along with the modifying effects of body mass index (BMI) were also examined. In the single-exposure model, the highest quantile of blood benzene (b = 0.89, 95%CI: 0.58 to 1.20), toluene (b = 0.87, 95%CI: 0.52 to 1.20), and ethylbenzene (b = 0.80, 95%CI: 0.46 to 1.10) was positively associated with PhenoAge.Accel compared to quantile 1. Mixed-exposure analyses revealed a consistent positive association between BTEX mixed exposure and PhenoAge.Accel (b = 0.88, 95%CI: 0.56 to 1.20), primarily driven by benzene (92.78%). The association between BTEX and PhenoAge.Accel was found to be partially mediated by inflammation and oxidative stress indicators (ranging from 3.2% to 13.7%). Additionally, BMI negatively modified the association between BTEX mixed exposure and PhenoAge.Accel, with a threshold identified at 36.2 kg/m^2. Furthermore, BMI negatively moderated the direct effect of BTEX mixed exposure on PhenoAge.Accel in moderated mediation models, while positively modified the link between SII and PhenoAge.Accel in the indirect path (binteraction = 0.04, 95%CI: 0.01 to 0.06). Overall, BTEX mixed exposure was associated with PhenoAge.Accel among US adults, with benzene may have reported most contribution, and inflammation and oxidative damage processes may partially explain this underlying mechanism. The study also highlighted the potential benefits of appropriate BMI increased. Additional large-scale cohort studies and experiments were necessary to substantiate these findings.

Association of per- and polyfluoroalkyl substances with the antioxidant bilirubin across pregnancy

BACKGROUND

In mechanistic and preliminary human studies, prenatal exposure to per- and polyfluoroalkyl substances (PFAS) is associated with oxidative stress, a potential contributor to maternal liver disease. Bilirubin is an endogenous antioxidant abundant in the liver that may serve as a physiological modulator of oxidative stress in pregnant people. Hence, our objective was to estimate the association between repeated measures of PFAS and bilirubin during pregnancy.

METHODS

The study population included 332 participants in the Atlanta African American Maternal-Child Cohort between 2014 and 2020. Serum samples were collected up to two times (early pregnancy: 6-18 gestational weeks; late pregnancy: 21-36 gestational weeks) for the measurement of perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and total bilirubin. We analyzed single PFAS with linear mixed effect regression and a mixture of the four PFAS with quantile g-computation. Models were repeated with a multiplicative interaction term to explore effect modification by study visit.

RESULTS

Overall, PFHxS was positively associated with bilirubin (β = 0.08, 95 % CI = 0.01, 0.15). We also found during late pregnancy, there was a positive association of PFHxS and the PFAS mixture with bilirubin (β = 0.12, 95 % CI = 0.02, 0.22; ψ = 0.19, 95 % CI = 0.03, 0.34, respectively). Finally, study visit modified the PFOA-bilirubin association (interaction p-value = 0.09), which was greater during early pregnancy (β = 0.08, 95 % CI = 0.01, 0.15).

CONCLUSION

In a prospective cohort of pregnant African Americans, an increase in PFOA, PFHxS, and the PFAS mixture was associated with an increase in bilirubin. Our results suggest that, depending on pregnancy stage, prenatal PFAS exposure disrupts the maternal liver antioxidant capacity.

Associations of healthy eating patterns with biological aging: national health and nutrition examination survey (NHANES) 1999-2018

BACKGROUND

Healthy dietary patterns have been negatively associated with methylation-based measures of biological age, yet previous investigations have been unable to establish the relationship between them and biological aging assessed through blood chemistry-based clinical biomarkers. We sought to assess the associations of 4 dietary metrics with 4 measures of biological age.

METHODS

Among 16,666 participants in NHANES 1999-2018, 4 dietary metrics [Dietary inflammatory index (DII), Dietary approaches to stop hypertension index (DASH), Alternate mediterranean diet score (aMED), and Healthy eating index-2015 (HEI-2015)] were calculated through the 'dietaryindex' R package. Twelve blood chemistry parameters were utilized to compute 4 indicators of biological age [homeostatic dysregulation (HD), allostatic load (AL), Klemera-Doubal method (KDM), and phenotypic age (PA)]. Binomial logistic regression models and restricted cubic spline (RCS) regression were employed to evaluate the associations.

RESULTS

All 4 dietary metrics were significantly associated with biological age acceleration or deceleration. In comparison to the lowest DII, the odds ratios (ORs) for accelerated HD, AL, KDM, and PA were 1.25 (1.08,1.45), 1.29 (1.11,1.50), 1.34 (1.08,1.65), and 1.61 (1.39,1.87) for the highest. The multivariable-adjusted ORs of the highest quartile of DASH, aMED, and HEI-2015 were 0.85 (0.73,0.97), 0.88 (0.74,1.04), and 0.84 (0.74,0.96) for HD, 0.64 (0.54,0.75), 0.61 (0.52,0.72), and 0.70 (0.59,0.82) for AL, 0.68 (0.54,0.85), 0.62 (0.50,0.76), and 0.71 (0.58,0.87) for KDM, and 0.50 (0.42,0.59), 0.64 (0.54,0.76), and 0.51 (0.44,0.58) for PA when compared with the lowest level. The findings were validated by the best-fitting dose-response curves for the associations. Among participants consuming dietary supplements (Pinteraction < 0.05), the positive effects of a healthy dietary pattern on biological aging were more pronounced. Systemic immune inflammation index (SII) and atherogenic index of plasma (AIP) were identified as being involved in and mediating the associations.

CONCLUSIONS

Biological aging assessed through blood chemistry-based clinical biomarkers is negatively associated with diet quality. The anti-aging benefits of improving the diet may be due to its ability to reduce inflammation and lower blood lipids.

Associations of daily eating frequency and nighttime fasting duration with biological aging in National Health and Nutrition Examination Survey (NHANES) 2003-2010 and 2015-2018

BACKGROUND

Information on the influences of daily eating frequency (DEF) and nighttime fasting duration (NFD) on biological aging is minimal. Our study investigated the potential associations of DEF and NFD with accelerated aging.

METHODS

Out of 24212 participants in NHANES 2003-2010 and 2015-2018, 4 predicted age metrics [homeostatic dysregulation (HD), Klemera-Doubal method (KDM), phenoAge (PA), and allostatic load (AL)] were computed based on 12 blood chemistry parameters. Utilizing 24-h dietary recall, DEF was measured by the frequency of eating occurrences, while NFD was determined by assessing the timing of the initial and final meals throughout the day. Weighted multivariate linear regression models and restricted cubic spline (RCS) were utilized to examine the associations.

RESULTS

Compared to DEF of ≤ 3.0 times, subjects with DEF ≥ 4.6 times demonstrated lower KDM residual [β: -0.57, 95% confidence-interval (CI): (-0.97, -0.17)] and PA residual [β: -0.47, 95% CI: (-0.69, -0.25)]. In comparison to NFD between 10.1 and 12.0 h, individuals with NFD ≤ 10.0 h were at higher HD [β: 0.03, 95% CI: (0.01, 0.04)], KDM residual [β: 0.34, 95% CI: (0.05, 0.63)], and PA residual [β: 0.38, 95% CI: (0.18, 0.57)]. Likewise, those with NFD ≥ 14.1 h also had higher HD [β: 0.02, 95% CI: (0.01, 0.04)] and KDM residual [β: 0.33, 95% CI: (0.03, 0.62)]. The results were confirmed by the dose-response relationships of DEF and NFD with predicted age metrics. Lactate dehydrogenase (LDH) and globulin (Glo) were acknowledged as implicated in and mediating the relationships.

CONCLUSIONS

DEF below 3.0 times and NFD less than 10.0 or more than 14.1 h were independently associated with higher predicted age metrics.

Inflammaging: The Next Challenge-Exploring the Role of Gut Microbiota, Environmental Factors, and Sex Differences

The term 'inflammaging' has been coined to describe the chronic state of inflammation derived from ongoing cycles of tissue damage and the subsequent immune responses. This inflammatory status contributes to the decline of organs and physiological functions, accelerates the aging process, and increases the risk of age-related illnesses and death. During aging, the gut microbiota (GM) undergoes significant changes, including a decreased diversity of species, a decline in beneficial bacteria, and a rise in proinflammatory ones, resulting in persistent low-grade inflammation. Moreover, environmental factors, such as diet and medications, contribute to age-related changes in GM and immune function, preventing or promoting inflammaging. This narrative review aims to clarify the underlying mechanisms of inflammaging and to specifically investigate the influence of GM and several environmental factors on these mechanisms, while also exploring potential differences related to sex. Moreover, lifestyle and pharmacological interventions will be suggested to promote healthy aging.

U-shaped association between sleep duration and biological aging: Evidence from the UK Biobank study

Previous research on sleep and aging largely has failed to illustrate the optimal dose-response curve of this relationship. We aimed to analyze the associations between sleep duration and measures of predicted age. In total, 241,713 participants from the UK Biobank were included. Habitual sleep duration was collected from the baseline questionnaire. Four indicators, homeostatic dysregulation (HD), phenoAge (PA), Klemera-Doubal method (KDM), and allostatic load (AL), were chosen to assess predicted age. Multivariate linear regression models were utilized. The association of sleep duration and predicted age followed a U-shape (All p for nonlinear <0.05). Compared with individuals who sleep for 7 h/day, the multivariable-adjusted beta of ≤5 and ≥9 h/day were 0.05 (95% CI 0.03, 0.07) and 0.03 (95% CI 0.02, 0.05) for HD, 0.08 (95% CI 0.01, 0.14) and 0.36 (95% CI 0.31, 0.41) for PA, and 0.21 (95% CI 0.12, 0.30) and 0.30 (95% CI 0.23, 0.37) for KDM. Significant independent and joint effects of sleep and cystatin C (CysC) and gamma glutamyltransferase (GGT) on predicted age metrics were future found. Similar results were observed when conducting stratification analyses. Short and long sleep duration were associated with accelerated predicted age metrics mediated by CysC and GGT.

Effect of liver cancer on the accumulation and hepatobiliary transport of per- and polyfluoroalkyl substances

In this study, we examined the distribution of per- and polyfluoroalkyl substances (PFASs) in liver and bile tissues from the patients with liver cancer (n = 202) and healthy controls (n = 30), and calculated the hepatobiliary transport efficiency (TB-L) of PFASs. Among 21 PFASs, 13 PFASs were frequently detected in the liver (median: 8.80-16.3 ng/g) and bile (median: 11.03-14.26 ng/mL) samples. PFAS concentrations in liver were positively correlated with age, with higher levels of PFASs in the older. Variance analysis showed that gender and BMI (Body Mass Index) have an important impact on the distribution of PFASs. A U-shaped trend in TB-L of PFASs with the increasing of carbon chain length was found for the first time, and the TB-L of most PFASs in the control was higher than that of those in cases (p < 0.05), suggesting that hepatic injury would affect their transport. PFASs were positively associated with liver injury biomarkers, including γ-glutamyl transferase (GGT), alanine aminotransferase (ALT), and total bilirubin (TB) levels (p < 0.05). This is the first study on examining the hepatobiliary transport characteristics of PFASs, which may help understand the connection between PFAS accumulation and liver cancer risk.

Exploring the Potential Link between PFAS Exposure and Endometrial Cancer: A Review of Environmental and Sociodemographic Factors

This exploratory narrative review paper delves into the intricate interplay between per- and polyfluoroalkyl substances (PFAS) exposure, sociodemographic factors, and the influence of stressors in the context of endometrial cancer. PFAS, ubiquitous environmental contaminants notorious for their persistence in the ecosystem, have garnered attention for their potential to disrupt endocrine systems and provoke immune responses. We comprehensively examine the various sources of PFAS exposure, encompassing household items, water, air, and soil, thus shedding light on the multifaceted routes through which individuals encounter these compounds. Furthermore, we explore the influence of sociodemographic factors, such as income, education, occupation, ethnicity/race, and geographical location and their relationship to endometrial cancer risk. We also investigated the role of stress on PFAS exposure and endometrial cancer risk. The results revealed a significant impact of sociodemographic factors on both PFAS levels and endometrial cancer risk. Stress emerged as a notable contributing factor influencing PFAS exposure and the development of endometrial cancer, further emphasizing the importance of stress management practices for overall well-being. By synthesizing evidence from diverse fields, this review underscores the need for interdisciplinary research and targeted interventions to comprehensively address the complex relationship between PFAS, sociodemographic factors, stressors, and endometrial cancer.

The mixed effect of Endocrine-Disrupting chemicals on biological age Acceleration: Unveiling the mechanism and potential intervention target

INTRODUCTION

Although previous studies investigated the potential adverse effects of endocrine-disrupting chemicals (EDCs) on biological age acceleration and aging-related diseases, the mixed effect of multiple types of EDCs on biological age acceleration, including its potential underlying mechanism, remains unclear.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) were used to analyze biological age measures, including Klemera-Doubal method biological age (KDM-BA), phenotypic age, and homeostatic dysregulation (HD). Weight quantile sum (WQS) regression was performed to screen biological age-related EDCs (BA-EDCs) and assess the mixed effect of BA-EDCs on biological age acceleration and aging-related disease. Targets of BA-EDCs were obtained from three databases, while heart aging-related genes were obtained from the Aging Anno database. Protein-protein interaction (PPI) network and MCODE algorithm were applied to identify potential interactions between BA-EDC targets and heart aging-related genes. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed to identify related pathways.

RESULTS

This cross-sectional study included 1,439 participants. A decile increase in BA-EDCs co-exposure was associated with 0.31 years and 0.17 years of KDM-BA and phenotypic age acceleration, respectively. The mixed effect of BA-EDCs was associated with an increased prevalence of atherosclerotic cardiovascular disease (ASCVD). Vitamins C and E demonstrated a significant interaction effect on the association between BA-EDCs and KDM-BA acceleration. PPI network and functional enrichment analysis indicated that the AGE-RAGE signaling pathway in diabetic complications was significantly enriched.

CONCLUSION

Our results showed that the co-exposure effect of BA-EDCs was associated with biological age acceleration and ASCVD, with the AGE-RAGE signaling pathway being the underlying mechanism. Vitamins C and E may also be an actionable target for preventing EDC-induced biological aging.

Association of dietary inflammatory potential, dietary oxidative balance score and biological aging

BACKGROUND & AIMS

The interaction between diet, inflammation, and oxidative stress significantly influences aging, but the available evidence has been limited. We evaluated potential associations of dietary inflammatory index (DII), dietary oxidative balance score (DOBS), and measures of biological aging.

METHODS

This cross-sectional study was performed among 8839 individuals from NHANES 2003-2014. DII and DOBS were determined by aggregating data from 26 to 17 a priori selected dietary components. Biological aging metrics included homeostatic dysregulation (HD), Klemera-Doubal method (KDM), phenotypic age (PA), and allostatic load (AL). Binomial logistic regression models and multivariate linear regression models were conducted.

RESULTS

The associations of dietary inflammation and oxidative stress potential and biological aging metrics were significant among American adults nationwide. Consuming foods with higher DII was significantly associated with accelerated HD 1.26 (1.10, 1.44), KDM 1.24 (1.06, 1.45), and PA 1.54 (1.33, 1.78). Compared with the lowest DOBS, the hazard ratios of accelerated HD, KDM, PA, and AL were 0.74 (0.64, 0.86), 0.80 (0.70, 0.92), 0.61 (0.52, 0.72) and 0.78 (0.63, 0.97), respectively. The adverse effects of pro-inflammatory and pro-oxidative diets on accelerated HD, KDM, and PA were 1.39 (1.18, 1.62), 1.28 (1.08, 1.51), and 1.76 (1.47, 2.10). Serum AST/ALT ratio and globulin were implicated in and mediate the aging effects.

CONCLUSIONS

Higher DII and/or lower DOBS are associated with higher markers of biological aging. Our research elucidates that diets may mitigate biological aging resulting from inflammation and/or oxidative stress.

Insight into the mechanisms of neuroendocrine toxicity induced by 6:2FTCA via thyroid hormone disruption

6:2 fluorotonic carboxylic acid (6:2 FTCA), a novel substitute for perfluorooctanoic acid (PFOA), is being used gradually in industrial production such as coatings or processing aids, and its detection rate in the aqueous environment is increasing year by year, posing a potential safety risk to aquatic systems and public health. However, limited information is available on the effects and mechanism of 6:2 FTCA. Therefore, this study was conducted to understand better the neuroendocrine effects of early exposure to 6:2 FTCA and the underlying mechanisms on zebrafish. In this study, zebrafish embryos were treated to varied doses of 6:2 FTCA (0, 0.08 μg/mL, 0.8 μg/mL and 8 μg/mL) at 4 h post-fertilization (hpf) for a duration of six days, which exhibited a pronounced inhibition of early growth and induced a disorganized swim pattern characterized by reduced total swim distance and average swim speed. Simultaneously, the thyroid development of zebrafish larvae was partially hindered, accompanied by decreased T3 levels, altered genes associated with the expression of thyroid hormone synthesis, transformation and transportation and neurotransmitters associated with tryptophan and tyrosine metabolic pathways. Molecular docking results showed that 6:2 FTCA has a robust binding energy with the thyroid hormone receptor (TRβ). Moreover, exogenous T3 supplementation can partially restore the adverse outcomes. Our findings indicated that 6:2 FTCA acts as a thyroid endocrine disruptor and can induce neuroendocrine toxic effects. Furthermore, our results show that targeting TRβ may be a potentially therapeutic strategy for 6:2 FTCA-induced neuroendocrine disrupting effects.