Effects of trichlorfon on maternal estrous cycle, oocyte maturation, and near-term fetal developmental outcome in mice

Urinary Organophosphate Metabolite Concentrations and Pregnancy Outcomes among Women Conceiving through in Vitro Fertilization in Shanghai, China

BACKGROUND

Animal studies suggest that pesticide exposure elicits endocrine changes, increases embryo implantation failure, and decreases litter size. However, only a few epidemiological studies have evaluated the effects of pesticides on the outcomes of in vitro fertilization (IVF) pregnancies.

OBJECTIVES

This study examined the associations between preconception organophosphate pesticides (OP) exposure and pregnancy outcomes among women undergoing IVF in a Chinese population.

METHODS

This study included 522 women with infertility who underwent IVF. Women were recruited from a prospective study, the China National Birth Cohort (CNBC), from Shanghai, China, between July 2017 and December 2018. Demographic and clinical information were collected from medical records and through questionnaires. Preconception exposure to OP was assessed by measuring six nonspecific dialkylphosphate (DAP) metabolites [diethylthiophosphate (DETP), diethylphosphate (DEP), diethyldithiophosphate (DEDTP), dimethylthiophosphate (DMTP), dimethylphosphate (DMP), dimethyldithiophosphate (DMDTP)] in urine samples collected at recruitment. Generalized estimating equation (GEE) models were used to evaluate the associations between OP and pregnancy outcomes.

RESULTS

Compared with women in the lowest quartile (Q1) of individual DEP and Σ4DAP (the sum of DMP, DMTP, DEP, and DETP), women in the highest quartile (Q4) had lower odds of successful implantation, clinical pregnancy, and live birth, and most of the negative trends were significant (p-trends<0.05). There were no significant associations between urinary DAP concentrations and early IVF outcomes, including total and mature oocyte counts, best embryo quality, fertilization, E2 trigger levels, and endometrial wall thickness.

CONCLUSION

Preconception OP exposure was inversely associated with successful implantation, clinical pregnancy, and live birth in women who underwent IVF. https://doi.org/10.1289/EHP7076.

Trichlorfon inhibits proliferation and promotes apoptosis of porcine trophectoderm and uterine luminal epithelial cells

Trichlorfon is an organophosphate insecticide widely used in agriculture. Additionally, it is applied to pigs for control of endo- and ectoparasites. Previous studies have shown the effects of trichlorfon in pigs during late stages of gestation; however, little is known about its effects during early pregnancy, including implantation and placentation. We investigated whether trichlorfon affects proliferation and apoptosis of porcine trophectoderm (pTr) and uterine luminal epithelial (pLE) cells. Trichlorfon inhibited the proliferation of pTr and pLE cells, as evidenced by cell cycle arrest, and altered the expression of proliferation-related proteins. In addition, trichlorfon induced cell death and apoptotic features, such as loss of mitochondrial membrane potential and DNA fragmentation, in pTr and pLE cells. Moreover, trichlorfon treatment decreased concentrations of Ca²⁺ in the cytoplasm in both cell lines and increased concentrations of Ca²⁺ in mitochondria of pTr cells. Trichlorfon inhibited the activation of phosphoinositide 3-kinase/AKT and mitogen-activated protein kinase signaling pathways in pTr and pLE cells. Therefore, we suggest that trichlorfon-treated pTr and pLE cells exhibited abnormal cell physiology which might lead to early pregnancy failure.

Triazophos-induced oxidative stress and histomorphological changes in ovary of female Wistar rats

Triazophos (TZ), a non-systemic broad spectrum organophosphate (OP), is being extensively used against a wide range of pests in agricultural practices. The present study was carried out to investigate the toxic effects of triazophos (TZ) in female Wistar rats. Three sub-chronic dose levels of TZ corresponding to 1/10th, 1/20th and 1/40th of LD50 were given for 30 days to adult female Wistar rats through oral intubation. During the treatment period estrous cycle was significantly altered. Activity levels of different oxidative stress (OS) parameters viz. catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx) and lipid peroxidation (LPO) were differentially altered in the ovary of treated rats. Estradiol levels were significantly high while progesterone levels were significantly reduced in plasma of 1/10th and 1/20th of LD50 TZ-treated rats. Histomorphological studies of ovary revealed increased follicular atresia and increased ovarian surface epithelial height in 1/10th and 1/20th of LD50 TZ-treated rats. Enhanced apoptosis and necrosis were also observed in ovarian granulosa cells at dose-dependent manner. Results infer that TZ exposure may lead to the number of pathophysiological conditions in female rats and severity increases at high doses.