Perinatal androgenic exposure and reproductive health effects female rat offspring

Safety of lactational exposure to venlafaxine on the rat mammary gland development and carcinogenesis in F1 female offspring

The chronic use of selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors (SNRIs) may result in human gynecomastia, mammoplasia, galactorrhea, and elevated breast cancer risk. As antidepressants are frequently used for postpartum depression (PPD) treatment, this study investigated the adverse effects of lactational exposure to venlafaxine (VENL, a selective SNRI) on mammary gland development and carcinogenesis in F1 female offspring. Thus, lactating Wistar rats (F0) received VENL by oral gavage at daily doses of 3.85, 7.7, or 15.4 mg/kg (N = 9, each group) from lactational day (LD 1) until the weaning of the offspring (LD 21). F1 female offspring were euthanized for mammary gland, and ovary histological analyses on the post-natal day (PND) 22 and 30 (1 pup/litter/period, N = 9, each group). At PND 22, other females (2 pups/litter, N = 18, each group) received a single dose of carcinogen N-methyl-N-nitrosourea (MNU, 50 mg/kg) intraperitoneally (i.p.) for tumor susceptibility assay until PND 250. Tumor incidence and latency were recorded and representative tumor samples were collected for histopathology. The results indicate that lactational exposure to VENL did not alter the development of the mammary gland (epithelial ductal tree or the mean number of terminal end buds), or the ovary (weight and primary, secondary, tertiary, and Graafian follicles) in prepubertal F1 female offspring. In addition, VENL exposure did not influence tumor incidence or tumor latency in adult female offspring that received MNU. Thus, the findings of this animal study indicated that lactational VENL exposure, a period similar to human PPD, did not exert an adverse effect on the mammary gland development at the prepubertal phase or on chemically induced mammary tumorigenesis in adult F1 female rats.

Short- and long-term effects on reproductive parameters of female Wistar rats after exposure to rosuvastatin starting in pre-puberty

•

Rosuvastatin is a lipid-lowering drug that inhibits cholesterol biosynthesis.

•

The exposure of female rats from pre-puberty to adulthood leads to alterations in estrous cycle, sexual behavior, serum prolactin levels, and weights of liver, pituitary and placenta.

•

No alterations were found in pubertal timing, uterine and ovarian morphology, serum levels of LH, FSH, testosterone and progesterone, and reproductive performance.

•

The alterations seem to be due disruption of hormonal signaling and to the pleiotropic effects of statins.

Statins are a class of drugs that act lowering lipid levels by inhibiting cholesterol biosynthesis. Additionally, statins can act by “pleiotropic effects”, related to the inhibition of synthesis of the other mevalonate pathway products. Rosuvastatin is a third-generation statin and has shown better results in reducing cholesterol concentrations when compared to other statins. Recent studies suggest that rosuvastatin may act as an endocrine disruptor that potentially damages the hormonal axis and, consequently reproductive development and function of male rats. However, the effects of rosuvastatin exposure on rat female reproductive parameters remain unknown. In this study female rats were exposed to rosuvastatin at the doses of 0 (control), 3, or 10 mg/Kg.bw⁻¹/day from pre-puberty to adulthood. No alterations in the female reproductive parameters were observed at a dose of 3 mg/Kg.bw⁻¹. However, females exposed to 10 mg/Kg.bw⁻¹ exhibited shorter estrous cycles, altered copulatory behavior, decreased serum prolactin level, and alterations in the liver, pituitary and placental weights, parameters to some extent influenced by the reproductive hormonal axis signaling pathway. On the other hand, pubertal onset, reproductive hormone levels, fertility, and histological parameters of the ovary, uterus, and placenta were unaltered by exposure to both doses of this statin. Thus, rosuvastatin exposure, at the higher dose, altered the reproductive function of female rats, probably due to the pleiotropic effects of this statin. Additional studies on the effects of this statin on female reproductive function and development are encouraged to better characterize its mode of action.

Prenatally androgenized female rats develop uterine hyperplasia when adult

Prenatal hyperandrogenization (PH) is hypothesized as one of the main factors contributing to the development of polycystic ovary syndrome (PCOS). In this study, we aimed to investigate the impact of prenatal exposure to androgen excess on the uterus when animals reach their adulthood. We found that PH altered the morphology of the uteri that show a hyperplastic morphology with increased total uterine thickness as well as luminal epithelium thickness, with both enhanced and altered distribution of glands as compared with controls. Morphological alterations were associated with an unbalanced homeostasis as assessed by the expression of regulators of cell cycle progression and cell death dynamics. PH also causes disturbances in the cell cycle of the uterine tissue and dysregulates cell death and survival pathways leading to the development of uterine hyperplasia. These findings suggest that PH may have a deleterious effect on the uterus.

Reproductive disorders in female rats after prenatal exposure to sodium arsenite

Arsenic is a metalloid widely found in the environment in organic and inorganic forms. Exposure to inorganic arsenic forms via drinking water has been associated with an increased incidence of negative health effects, including reproductive disorders and dysfunction of the endocrine system. However, the impact of arsenic exposure on female reproductive development is still unclear. Therefore, in the present study, we evaluated the effects of prenatal exposure to arsenic on the initial sexual development and puberty onset, and in the morphology of the female reproductive organs, estrous cycle regularity and fertility parameters during adulthood. To do that, pregnant female Wistar rats were exposed to 10 mg/L sodium arsenite via drinking water from gestational day (GD) 1 until GD 21 and the female offspring was evaluated in different postnatal days. Our results showed that prenatal arsenic exposure induced a decrease of litter weight and morphological masculinization in females at postnatal day 1. Moreover, these females had a delay in the age of puberty onset and alteration in estrous cycle number and length. During adulthood, females from the sodium arsenite group showed an increase in endometrium, myometrium and perimetrium areas, and an imbalance in uterine antioxidant enzyme activity. These animals also presented an increase in post-implantation loss and reabsorption number, leading to reduced viable fetus number. In conclusion, prenatal arsenic exposure in rats was able to promote female masculinization, alter sexual development and impair reproductive performance.

Reproductive disorders in female rats after prenatal exposure to betamethasone

Betamethasone is the drug of choice for antenatal treatment, promoting fetal lung maturation and decreasing mortality. Previous studies in rats reported male programming and alteration in sperm parameters and sexual behavior following intrauterine betamethasone exposure. The impact on the female reproductive development is not known. In this study, rat female offspring was assessed for sexual development, morphophysiology of the reproductive tract and fertility after maternal exposure to 0.1 mg kg^-1 of betamethasone or vehicle on gestational days 12, 13, 18 and 19. The treatment promoted reduction of litter weight on postnatal day 1, morphological masculinization in females, delay in the age of puberty onset, reduction in estrus number, increase in estrous cycle length and increase in luteinizing hormone serum levels and uterus weight. The females from the betamethasone group showed an increase of myometrial uterine area and decrease in endometrial uterine area. These animals also performed less lordosis during the sexual behavior test and showed impaired reproductive performance. The uterus showed higher contraction in the treated group as shown by a pharmacological assay. In conclusion, prenatal betamethasone exposure in rats promoted female masculinization, altered sexual development and reproductive parameters. Copyright © 2017 John Wiley & Sons, Ltd.

Perinatal exposure to androgen excess and the effects on the rat uterine estradiol responsiveness

Androgen exposure during sexual development induces alterations in steroidal target tissues. The objective of this study was to evaluate the uterine responsiveness to estradiol after perinatal androgenization. Pregnant Wistar rats were exposed to corn oil or testosterone propionate at 0.05, 0.1, or 0.2 mg/kg from gestational day 12 until postnatal day 21. Female offspring was challenged with estradiol (E₂ ) after weaning (0.4 mg/kg) and at adulthood (10 or 100 µg/day), when the pituitary response was also evaluated. At adulthood, control and 0.05 mg/kg groups presented a uterine weight increment when exposed to 100 µg/day of E₂ , 0.1 mg/kg group only responded to 10 µg/day of E₂ , and the 0.2 mg/kg group showed increased uterine weight at both doses. The pituitary weight was similarly increased after estradiol stimulation in all experimental groups. In conclusion, testosterone propionate exposure induced an abnormal stimulation of uterine tissue growth by estrogen stimulus without affecting pituitary response. More studies are needed to clarify whether these alterations are capable of impairing the reproductive capacity of the female tract. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1460-1468, 2016.

Comparative Cytotoxicity and Sperm Motility Using a Computer-Aided Sperm Analysis System (CASA) for Isomers of Phthalic Acid, a Common Final Metabolite of Phthalates

The general population is exposed to phthalates through consumer products, diet, and medical devices. Phthalic acid (PA) is a common final metabolite of phthalates, and its isomers include isophthalic acid (IPA), terephthalic acid (TPA), and phthalaldehyde (o-phthalic acid, OPA). The purpose of this study was to investigate whether PA and PA isomers exert reproductive toxicity, including altered sperm movement. In vitro cell viability assays were comparatively performed using Sertoli and liver cell lines. In animal experiments, PA or PA isomers (10, 100, or 1000 mg/kg) were administered orally to Sprague-Dawley (SD) rats, and semen samples were analyzed by computer-aided sperm analysis (CASA). PA treatment produced a significant effect on curvilinear velocity (VCL), straight-line velocity (VSL), mean velocity or average path velocity (VAP), amplitude of lateral head displacement (ALH), and frequency of head displacement or beat cross-frequency (BCF), whereas IPA, TPA, and OPA induced no marked effects. In vitro cell viability assays showed that mouse normal testis cells (TM4) and human testis cancer cells (NTERA 2 cl. D1) were more sensitive to PA and OPA than mouse liver normal cells (NCTC clone 1469) and human fetal liver cells (FL 62891). Our study suggests that PA and PA isomers specifically produced significant in vitro and in vivo reproductive toxicity, particularly sperm toxicity and testis cell cytotoxicity. Of the isomers examined, PA appeared to be the most toxic and may serve as a surrogate biomarker for reproductive toxicity following mixed exposure to phthalates.