Endocrine disruptive actions of inhaled benzo(a)pyrene on ovarian function and fetal survival in fisher F-344 adult rats

Abstract

This study evaluated the effect of inhaled BaP on female reproductive function. Rats were exposed to 50, or 75 or 100 μg BaP/m3, four hours a day for 14 days via inhalation. Plasma E2, P4, LH and FSH concentrations were determined. Ovarian BaP metabolism and aryl hydrocarbon hydrolase (AHH) activity at proestrus were determined and fertility evaluations were conducted. Ovulation rate and number of pups/litter were reduced in rats exposed to 100 μg BaP/m3 compared with other treatment and control groups. Plasma concentrations of E2, and LH were significantly reduced at proestrus in BaP-exposed versus those of controls whereas those of P4 were significantly reduced at diestrus I. The activity of AHH in ovarian and liver tissues and concentrations of BaP 7,8-diol and BaP 3,6-dione metabolites increased in an exposure concentration-dependent manner. These data suggest that exposure of rats to BaP prior to mating contributes to reduced ovarian function and fetal survival.

Gestational N-hexane inhalation alters the expression of genes related to ovarian hormone production and DNA methylation states in adult female F1 rat offspring

“…Abnormalities in the female oestrus cycle are often closely related to changes in the levels of sex hormones (Archibong et al, 2012). Oestradiol and progesterone are the primary sex hormones secreted by the ovaries, and ovarian granulosa cells are a key cell type involved in the synthesis and secretion of sex hormones (Zelinski-Wooten et al, 1993).…”

Altered expression of histone deacetylases, inflammatory cytokines and contractile‐associated factors in uterine myometrium of Long Evans rats gestationally exposed to benzo[a]pyrene

“…To our knowledge, this is the first report on the length of gestation in rats treated with BaP. Other studies reported decreases in fetal survival and fetal growth in F‐344 rats exposed to BaP through inhalation (Archibong et al ., , ). BaP was reported to metabolize in uterine tissues (Ramesh et al ., ).…”

Oxidative stress in reproductive toxicology

“…Women who are exposed to the prototypical PAH (BaP) are more likely at a higher risk for infertility as exemplified by lower success rates in BaP-exposed women when using assisted reproductive technologies to attempt pregnancies [27]. In animal studies, exposure of adult F-344 adult female rats to inhaled BaP significantly reduced plasma concentrations of estradiol-17β (E 2 ), and luteinizing hormone (LH) on proestrus, progesterone (P 4 ) on diestrus I, ovulation rate and when mated, sustained a significant reduction in fetal survival compared to their unexposed counterparts [28]. The presence of dioxin and dioxin-like compounds in abdominal fat have for many years been believed to be associated with endometriosis-linked infertility albeit the literature is conflicting [29].…”