Copulatory efficiency and fertility in male rats exposed perinatally to flutamide

Insights from the maternal lineage of the F2 generation after exposure to an environmentally relevant dose of benzo(a)pyrene in the male rats of F0 generation

Benzo(a)pyrene (BaP) is a substance with the potential to induce endocrine disruption in the F0 generation and cause adverse multigenerational effects (F1 generation) for reproductive parameters in rats. The objective of this study was to investigate the occurrence of transgenerational inheritance in the reproductive aspects of male and female rats belonging to the F2 generation (MF2). This investigation was conducted following the exposure of male rats from the F0 generation to BaP to assess potential effects on subsequent generation from the maternal lineage (F1). For that, juvenile male Wistar rats (F0) were orally exposed to BaP (0.1 µg/kg/day) for 31 consecutive days. In adulthood, they were mated with untreated females to obtain female offspring (F1), which later produced the MF2. In the MF2 generation, both males and females exhibited increased body weight on postnatal day (PND) 1. In MF2 males, we observed delayed preputial separation, altered pup weight, reduced levels of follicle-stimulating hormone (FSH), increased intratesticular testosterone levels, decreased type A sperm, epididymal disturbances, reduced 5 α-reductase activity, increased testicular proliferation, and alterations in testicular antioxidant enzymes. In MF2 females, we noted morphological uterine enlargement, reduced sexual activity, and decreased progesterone levels. The findings suggest that the alterations observed in both MF2 males and females can be attributed to modifications in the sperm from F0 generation, which were subsequently transmitted to F1 females and MF2 generation due to BaP exposure.

Paternal low-dose benzo(a)pyrene exposure in rats impairs sexual development and fertility of the paternal lineage in F2 generation: A transgenerational study

The field of Paternal Origins of Health and Disease (POHaD) is highly relevant but remains under-explored. The F2 generation from males indirectly exposed (F1 - via germ cells) to benzo(a)pyrene (BaP), named PF2, was investigated in this study under parameters of sexual development and reproductive performance of male and female rats. Male Wistar rats (F0) were exposed to BaP (0.1µg/kg/day) for 31 consecutive days (gavage) during prepuberty. The F0 rats were mated with untreated females to produce male offspring (F1), which were exposed to BaP via germ cells. The F1 males were later mated with untreated females to obtain the PF2 generation, which was the focus of our investigation. Our findings showed that PF2 males exhibited a decrease in anogenital distance, fertility potential, testosterone levels, and type A sperm. Meanwhile, PF2 females had an earlier vaginal opening, lower lordosis scores, and decreased fertility. Furthermore, changes in the histomorphology of the testis/epididymis and ovary/uterus were observed. The repercussions of the PF2 generation indicate that these animals showed losses in both sexual development and fertility potential, and we can conclude that this damage remained due to paternal transgenerational inheritance caused by a low dose of BaP.

Photochemical reaction of glucocorticoids in aqueous solution: Influencing factors and photolysis products

Glucocorticoids (GCs), as endocrine disruptors, have attracted widespread attention due to their impacts on organisms' growth, development, and reproduction. In the current study, the photodegradation of budesonide (BD) and clobetasol propionate (CP), as targeted GCs, was investigated including the effects of initial concentrations and typical environmental factors (Cl^-, NO₂^-, Fe³⁺, and fulvic acid (FA)). The results showed that the degradation rate constants (k) were 0.0060 and 0.0039 min^-1 for BD and CP at concentration of 50 μg·L^-1, and increased with the initial concentrations. Under the addition of Cl^-, NO₂^-, and Fe³⁺ to the GCs/water system, the photodegradation rate was decreased with increasing Cl^-, NO₂^-, and Fe³⁺ concentrations, which were in contrast to the addition of FA. Electron resonance spectroscopy (EPR) analysis and the radical quenching experiments verified that GCs could transition to the triplet excited states of GCs (³GCs*) for direct photolysis under irradiation to undergo, while NO₂^-, Fe³⁺, and FA could generate ·OH to induce indirect photolysis. According to HPLC-Q-TOF MS analysis, the structures of the three photodegradation products of BD and CP were elucidated, respectively, and the phototransformation pathways were inferred based on the product structures. These findings help to grasp the fate of synthetic GCs in the environment and contribute to the understanding of their ecological risks.

Estrogen imprinting compromises male sexual behavior and affects the number of androgen-receptor-expressing hypothalamic neurons†

Neonatal exposure to high-dose 17β-estradiol (E2) affects the morphology and physiology of sex and accessory sex organs in the long term. In this study, we examined the effects of E2 imprinting on male sexual behavior, fertility, and the number of androgen receptor (AR)-expressing cells in the hypothalamus. E2-treated males showed copulatory behavior represented by mounts and/or intromissions, demonstrating the preservation of aspects of male behavior. They had slightly increased latency for first intromission and a reduced number of ejaculations, associated with a 50% reduction in the fertility index. AR expression in the hypothalamus was assessed by RT-PCR, western blotting, and immunohistochemistry. Treated rats had a significantly lower ventral prostate (VP) weight, demonstrating the efficacy of the treatment. The AR mRNA and protein content in the hypothalamus of E2-treated animals was reduced to the levels of females. AR-expressing cell counts in the ventromedial, anterior medial preoptic, paraventricular nuclei, and preoptic areas were different from control males, and similar to those of females. In conclusion, E2 imprinting resulted not only in ill-developed sexual organs, but also affected sexual behavior, resulting in a female-type hypothalamus, at least with respect to the abundance of AR mRNA and protein and the number of AR-expressing cells in important regions/tracts.

Effects of treatment with Hypoxis hemerocallidea extract on sexual behaviour and reproductive parameters in male rats

Hypoxis hemerocallidea is used in traditional medicine in South Africa, for the treatment of male reproductive ailments and various chronic illnesses. Despite chronic use, its effects on male reproductive system are unknown. Male Wistar rats were treated orally daily for 28 (n = 18) and 56 days (n = 18). Treatment groups (n = 6/group) per treatment period were as follows: untreated control, 150 mg/kg and 300 mg/kg 70% ethanolic extract of H. hemerocallidea. Sexual behaviour observations were performed on days 17 and 42 of the study. Sperm, biochemical and testicular histopathological studies were carried out. Arousal and libido and serum testosterone increased after 56 days of treatment. There was an increase in epididymal sperm count at both treatment doses, with the 300 mg/kg dose showing a higher sperm count (p < .05) compared to the 150 mg/kg treatment group. The higher 300 mg/kg dose also showed an increase (p < .05) in sperm motility after 56 days of treatment. Histology showed an increase in germinal layer thickness, consistent with the observed increase in sperm count. Testicular oxidative status improved after 56 days of treatment. Results suggest that chronic treatment with H. hemerocallidea may improve male sexual function and fertility parameters and may protect testes from oxidative damage.

Flutamide effects on morphology of reproductive organs and liver of Neotropical Anura, Rhinella schneideri

Water contamination is one of the factors influencing the decline of amphibians. Flutamide is an antiandrogenic medicine that occurs as water contaminant. This compound especially affects the reproductive organs, but it can also show hepatotoxic effects. The Bufonidae family has a peculiar organ named Bidder's organ, considered by some authors as a rudimentary ovary, but capable to respond to some external stimuli. This study investigated flutamide effects on testes and Bidder's organ germ cells, liver pigmentation, and sexual hormones levels in Rhinella schneideri males. We randomly divided 15 males in three groups (N=5): two groups were injected with flutamide, at 1 and 5mg/kg, while the control group received only mineral oil, for 7days. After euthanasia, blood samples were collected and the organs were sent to histological routine. In the testes, both treatments caused an increase in spermatogonia and spermatocytes, and a decrease in spermatozoa and locular area. In the Bidder's organ, the final diplotene oocytes increased, but the initial diplotene, degrading and atresic oocytes reduced in both treatments. The lipofuscin in the Bidder's organ was not affected. In the liver, melanin and lipofuscin increased only for the 1mg/kg flutamide treatment. The 5mg/kg treatment did not affect the liver. Serum testosterone and estradiol levels did not vary compared with the control group. This compound has antiandrogenic activity, which can affect the spermatogenetic process. The decrease in degrading and atresic Bidderian oocytes indicated that flutamide could stimulate the organ, retarding the degradation processes. The increase in liver melanin, which has protective role, and lipofuscin, a sign of degradation, indicates that flutamide cause hepatotoxic effects. So we conclude that flutamide negatively affects the testes, especially by reducing the sperm area, and the liver, inducing cell degradation and producing protective responses. Furthermore, the compound encourages lower degradation rates of the Bidder's organ germ cells.

Hormonal imprinting in the central nervous system: causes and consequences

The notion of the perinatal „hormonal imprinting” has been published at first in 1980 and since that time it spred expansively. The imprintig develops at the first encounter between the developing receptor and the target hormone – possibly by the alteration of the methylation pattern of DNA – and it is transmitted to the progeny generations of the cell. This is needed for the complete development of the receptor’s binding capacity. However, molecules similar to the target hormone (hormone-analogues, drugs, chemicals, environmental pollutants) can also bind to the developing receptor, causing faulty imprinting with life-long consequences. This can promote pathological conditions. Later it was cleared that in other critical periods such as puberty, imprinting also can be provoked, even in any age in differentiating cells. The central nervous system (brain) also can be mistakenly imprinted, which durably influences the dopaminergic, serotonergic and noradrenergic system and this can be manifested – in animal experiments – in alterations of the sexual and social behavior. In our modern age the faulty hormonal imprintig is inavoidable because of the mass of medicaments, chemicals, the presence of hormone-like materials (e.g. soya phytosteroids) in the food, and environmental pollutants. The author especially emphasizes the danger of oxytocin, as a perinatal imprinter, as it is used very broadly and can basically influence the emotional and social spheres and the appearance of certain diseases such as auitism, schizophrenia and parkinsonism. The danger of perinatal imprinters is growing, considering their effects on the human evolution. Orv. Hetil., 2013, 154, 128–135.

Prenatal testosterone supplementation alters puberty onset, aggressive behavior, and partner preference in adult male rats

The objective of this study was to investigate whether prenatal exposure to testosterone (T) could change the body weight (BW), anogenital distance (AGD), anogenital distance index (AGDI), puberty onset, social behavior, fertility, sexual behavior, sexual preference, and T level of male rats in adulthood. To test this hypothesis, pregnant rats received either 1 mg/animal of T propionate diluted in 0.1 ml peanut oil or 0.1 ml peanut oil, as control, on the 17th, 18th and 19th gestational days. No alterations in BW, AGD, AGDI, fertility, and sexual behavior were observed (p > 0.05). Delayed onset of puberty (p < 0.0001), increased aggressive behavior (p > 0.05), altered pattern of sexual preference (p < 0.05), and reduced T plasma level (p < 0.05) were observed for adult male rats exposed prenatally to T. In conclusion, the results showed that prenatal exposure to T was able to alter important aspects of sexual and social behavior although these animals were efficient at producing descendants. In this sense more studies should be carried to evaluated the real impact of this hormonal alteration on critical period of sexual differentiation on humans, because pregnant women exposed to hyperandrogenemia and then potentially exposing their unborn children to elevated androgen levels in the uterus can undergo alteration of normal levels of T during the sexual differentiation period, and, as a consequence, affect the reproductive and behavior patterns of their children in adulthood.