Association between follicular fluid phthalate concentrations and extracellular vesicle microRNAs expression

Abstract

STUDY QUESTION Are phthalate metabolite concentrations in follicular fluid (FF) associated with the expression of extracellular vesicle microRNAs (EV-miRNAs)? SUMMARY ANSWER Phthalate metabolite concentrations are associated with the expression of EV-miRNA and their associated pathways in FFs. WHAT IS KNOWN ALREADY Phthalate metabolites were recently detected in FF. Urinary phthalate metabolite concentrations alter the expression of EV-miRNAs in FF. STUDY DESIGN, SIZE, DURATION Prospective study including 105 women recruited between January 2014 and August 2016 in a tertiary university-affiliated hospital. PARTICIPANTS/MATERIALS, SETTING, METHODS We assessed FF concentrations of 12 phthalate metabolites. EV-miRNAs were isolated from aliquots of the same FF, and their expression profiles were measured using a human miRNA panel. Associations between EV-miRNAs that were present in >50% of the samples and phthalate metabolites that were measured in >74% of the FF samples were tested. Genes regulated by EV-miRNAs that were found to be significantly (false discovery rate q-value < 0.1) correlated with FF-phthalates were analyzed for pathways linked with female fertility using miRWalk2.0 Targetscan database, DAVID Bioinformatics Resources and Kyoto Encyclopedia of Genes and Genomes (KEGG). MAIN RESULTS AND THE ROLE OF CHANCE Of 12 phthalate metabolites, 11 were measured in at least one FF sample. Mono (6-COOH-2-methylheptyl) phthalate (MCOMHP), mono-2-ethyl-5-carboxypentyl phthalate (mECPP), mono-n-butyl phthalate (MnBP), monobenzyl phthalate (MBzP), mono-isobutyl phthalate (MiBP), monoethyl phthalate (MEP) and mono (7-COOH-2-methyloctyl) phthalate (MCOMOP) were detected in more than 74% of the samples. Of 754 EV-miRNAs tested, 39 were significantly associated either with MEP, MBzP, MCOMOP, MCOMHP and/or with mECPP, after adjusting for multiple testing (P < 0.05). KEGG-based pathway enrichment analysis of the genes regulated by these miRNAs showed that these EV-miRNAs may be involved in pathways related to ovary or oocyte development, maturation and fertilization. LIMITATIONS, REASONS FOR CAUTION The use of miRNA panel array limits the number of potential relevant miRNAs. Moreover, several of the phthalate metabolites examined may be biased due to internal (enzymatic activity) or external (contamination in medical interventions) causes. WIDER IMPLICATIONS OF THE FINDINGS Phthalate metabolites may alter follicular EV-miRNAs profile and thus impair pathways that are involved with oocyte development, maturation and fertilization. Our results contribute to understanding of possible mechanism(s) in which endocrine disruptor chemicals interfere with female fertility. STUDY FUNDING/COMPETING INTERESTS This work was supported by the National Institutes of Environmental Health Sciences [Grant R21-ES024236]; and Environmental Health Fund, Israel [Grant 1301], no competing interests. TRIAL REGISTRATION NUMBER N/A.

Significant changes in follicular fluid phthalate metabolite levels reflect the lifestyle changes brought about by the strict COVID-19 lockdown in India

“…Although phthalates have short half-lives (33,34), this study has demonstrated the accumulation of all six phthalate metabolites in the FF of 176 women with a detection rate of 98.9%-100% (Table 1), affirming their presence in the ovarian microenvironment (35)(36)(37)(38). Follicular fluid comprises a delicate balance of hormones, growth factors, reactive oxygen species, and antioxidants working in tandem toward the developmental potential of the oocyte (39).…”

“…The same research group in an earlier study by Du Y et al (35), showed that even at low concentrations, certain phthalate metabolites, including MEP, MBP, and metabolites of DEHP in the FF of (n ¼ 194) women could alter the levels of intrafollicular reproductive hormones, suggesting the adverse effect of phthalate exposure on theca and granulosa cell function. In a more recent study, Barnett-Itzhaki Z et al (38) showed a significant correlation between relatively low levels of phthalate metabolites such as MEP and metabolites of DiNP and DiDP detected in the FF of (n¼105) women and follicular extracellular vesicle microRNAs profiles, suggesting impairment of pathways involved in the oocyte development, maturation, and fertilization. It is therefore imperative that women who are trying to conceive should reduce their exposure to phthalates by modifying their lifestyle and consumption patterns.…”

MicroRNA-375 Mediated Regulation on Pre-mRNA Processing Factor 3 in Zebrafish Embryos Exposed to Di-(2-ethylhexyl)phthalate at Low Concentrations

“…Phthalate metabolites altered the follicular miRNA profile (miR-375 was downregulated), thereby impairing the pathways involved in oocyte development, maturation, and fertilization, as well as interfering with female fertility and embryo mass. 30,31 Furthermore, phthalate exposure decreased miRNA-mRNA linkage and identified miR-375 as a potential critical regulator of breast carcinogenesis. 37 Here, we found that miR-375 was significantly downregulated in zebrafish upon DEHP exposure.…”

“…Our previous studies indicated that the expression of miR-375 was altered by DEHP. , miRNA-mRNA prediction indicated that pre-mRNA processing factor 3 ( PRPF3 ) is a likely target mRNA for miR-375 whose expression is altered by DEHP exposure. However, the interrelation between miR-375 and PRPF3 has not yet been confirmed experimentally.…”

Identification of CDK2-Related Immune Forecast Model and ceRNA in Lung Adenocarcinoma, a Pan-Cancer Analysis

“…We explored CDK2 related miRNAs from Targetscan 16 ( Barnett-Itzhaki et al, 2021 ), miRWalk 17 ( Sheng L. P. et al, 2021 ), mirDB 18 ( Ren et al, 2021 ), Starbase 19 ( Li et al, 2014 ). All miRNAs from four databases were analyzed by Venn map 20 .…”