Maternal caffeine intake and DNA methylation in newborn cord blood

Examination of newborn DNA methylation among women with polycystic ovary syndrome/hirsutism

Research suggests that polycystic ovary syndrome (PCOS) traits (e.g., hyperandrogenism) may create a suboptimal intrauterine environment and induce epigenetic modifications. Therefore, we assessed the associations of PCOS traits with neonatal DNA methylation (DNAm) using two independent cohorts. DNAm was measured in both cohorts using the Infinium MethylationEPIC array. Multivariable robust linear regression was used to determine associations of maternal PCOS exposure or preconception testosterone with methylation β-values at each CpG probe and corrected for multiple testing by false-discovery rate (FDR). In the birth cohort, 12% (102/849) had a PCOS diagnosis (8.1% PCOS without hirsutism; 3.9% PCOS with hirsutism). Infants exposed to maternal PCOS with hirsutism compared to no PCOS had differential DNAm at cg02372539 [β(SE): -0.080 (0.010); FDR p = 0.009], cg08471713 [β(SE):0.077 (0.014); FDR p = 0.016] and cg17897916 [β(SE):0.050 (0.009); FDR p = 0.009] with adjustment for maternal characteristics including pre-pregnancy BMI. PCOS with hirsutism was also associated with 8 differentially methylated regions (DMRs). PCOS without hirsutism was not associated with individual CpGs. In an independent preconception cohort, total testosterone concentrations were associated with 3 DMRs but not with individual CpGs, though the top quartile of testosterone compared to the lowest was marginally associated with increased DNAm at cg21472377 near an uncharacterized locus (FDR p = 0.09). Examination of these probes and DMRs indicate they may be under foetal genetic control. Overall, we found several associations among newborns exposed to PCOS, specifically when hirsutism was reported, and among newborns of women with relatively higher testosterone around conception.

Maternal caffeine consumption during pregnancy and offspring cord blood DNA methylation: an epigenome-wide association study meta-analysis

Background: Prenatal caffeine exposure may influence offspring health via DNA methylation, but no large studies have tested this. Materials & methods: Epigenome-wide association studies and differentially methylated regions in cord blood (450k or EPIC Illumina arrays) were meta-analyzed across six European cohorts (n = 3725). Differential methylation related to self-reported caffeine intake (mg/day) from coffee, tea and cola was compared with assess whether caffeine is driving effects. Results: One CpG site (cg19370043, PRRX1) was associated with caffeine and another (cg14591243, STAG1) with cola intake. A total of 12-22 differentially methylated regions were detected with limited overlap across caffeinated beverages. Conclusion: We found little evidence to support an intrauterine effect of caffeine on offspring DNA methylation. Statistical power limitations may have impacted our findings.

Genotoxic effects of caffeine in female mice exposed during pregnancy and lactation period and their offspring

Caffeine is a widely consumed substance, and there is a discussion about its effects when ingested by women during pregnancy and lactation. We aimed to identify the genotoxic effects of caffeine in female mice that consumed it during pregnancy and lactation periods and its consequences in their offspring. Thirty-six couples of Swiss mice received water or caffeine (0.3 and 1.0 mg/mL) treatment during pregnancy and lactation. The male and female offspring were divided into 12 groups according to the treatment administered to the female mice. Genotoxicity was assessed using the comet assay and the micronucleus test. Both doses of caffeine showed genotoxic effects in pregnant and lactating mice groups compared to groups not administered caffeine. In relation to offspring, it can be observed that females and males of the offspring had low weight in early life. In both female and male offspring, genotoxicity was detected in the blood, liver, and kidney tissues. Thus, from the present study, we can suggest that the caffeine consumed by female mice during the periods of pregnancy and lactation led to genotoxic effects in their offspring.

Epigenetics as a Biomarker for Early-Life Environmental Exposure

PURPOSE OF REVIEW

There is interest in evaluating the developmental origins of health and disease (DOHaD) which emphasizes the role of prenatal and early-life environments on non-communicable health outcomes throughout the life course. The ability to rigorously assess and identify early-life risk factors for later health outcomes, including those with childhood onset, in large population samples is often limited due to measurement challenges such as impractical costs associated with prospective studies with a long follow-up duration, short half-lives for some environmental toxicants, and lack of biomarkers that capture inter-individual differences in biologic response to external environments.

RECENT FINDINGS

Epigenomic patterns, and DNA methylation in particular, have emerged as a potential objective biomarker to address some of these study design and exposure measurement challenges. In this article, we summarize the literature to date on epigenetic changes associated with specific prenatal and early-life exposure domains as well as exposure mixtures in human observational studies and their biomarker potential. Additionally, we highlight evidence for other types of epigenetic patterns to serve as exposure biomarkers. Evidence strongly supports epigenomic biomarkers of exposure that are detectable across the lifespan and across a range of exposure domains. Current and future areas of research in this field seek to expand these lines of evidence to other environmental exposures, to determine their specificity, and to develop predictive algorithms and methylation scores that can be used to evaluate early-life risk factors for health outcomes across the life span.