Dataset Information

Cellular and molecular effect of MEHP Involving LXR? in human fetal testis and ovary.

ABSTRACT:

Background

Phthalates have been shown to have reprotoxic effects in rodents and human during fetal life. Previous studies indicate that some members of the nuclear receptor (NR) superfamilly potentially mediate phthalate effects. This study aimed to assess if expression of these nuclear receptors are modulated in the response to MEHP exposure on the human fetal gonads in vitro.

Methodology/principal findings

Testes and ovaries from 7 to 12 gestational weeks human fetuses were exposed to 10(-4)M MEHP for 72 h in vitro. Transcriptional level of NRs and of downstream genes was then investigated using TLDA (TaqMan Low Density Array) and qPCR approaches. To determine whether somatic or germ cells of the testis are involved in the response to MEHP exposure, we developed a highly efficient cytometric germ cell sorting approach. In vitro exposure of fetal testes and ovaries to MEHP up-regulated the expression of LXR?, SREBP members and of downstream genes involved in the lipid and cholesterol synthesis in the whole gonad. In sorted testicular cells, this effect is only observable in somatic cells but not in the gonocytes. Moreover, the germ cell loss induced by MEHP exposure, that we previously described, is restricted to the male gonad as oogonia density is not affected in vitro.

Conclusions/significance

We evidenced for the first time that phthalate increases the levels of mRNA for LXR?, and SREBP members potentially deregulating lipids/cholesterol synthesis in human fetal gonads. Interestingly, this novel effect is observable in both male and female whereas the germ cell apoptosis is restricted to the male gonad. Furthermore, we presented here a novel and potentially very useful flow cytometric cell sorting method to analyse molecular changes in germ cells versus somatic cells.

SUBMITTER: Muczynski V

PROVIDER: S-EPMC3484128 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Cellular and molecular effect of MEHP Involving LXRα in human fetal testis and ovary.

Muczynski Vincent V Lecureuil Charlotte C Messiaen Sébastien S Guerquin Marie-Justine MJ N'tumba-Byn Thierry T Moison Delphine D Hodroj Wassim W Benjelloun Hinde H Baijer Jan J Livera Gabriel G Frydman René R Benachi Alexandra A Habert René R Rouiller-Fabre Virginie V

PloS one 20121030 10

<h4>Background</h4>Phthalates have been shown to have reprotoxic effects in rodents and human during fetal life. Previous studies indicate that some members of the nuclear receptor (NR) superfamilly potentially mediate phthalate effects. This study aimed to assess if expression of these nuclear receptors are modulated in the response to MEHP exposure on the human fetal gonads in vitro.<h4>Methodology/principal findings</h4>Testes and ovaries from 7 to 12 gestational weeks human fetuses were expo ...[more]

PMID: 23118965

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