Male reproductive system and simulated high-altitude environment: preliminary results in rats

The ubiquitous existence of microplastics and nanoplastics raises concerns about their potential impact on the human reproductive system. Limited data exists on microplastics within the human reproductive system and their potential consequences on sperm quality. Our objectives were to quantify and characterize the prevalence and composition of microplastics within both canine and human testes and investigate potential associations with the sperm count, and weights of testis and epididymis. Using advanced sensitive pyrolysis-gas chromatography/mass spectrometry, we quantified 12 types of microplastics within 47 canine and 23 human testes. Data on reproductive organ weights, and sperm count in dogs were collected. Statistical analyses, including descriptive analysis, correlational analysis, and multivariate linear regression analyses were applied to investigate the association of microplastics with reproductive functions. Our study revealed the presence of microplastics in all canine and human testes, with significant inter-individual variability. Mean total microplastic levels were 122.63 µg/g in dogs and 328.44 µg/g in humans. Both humans and canines exhibit relatively similar proportions of the major polymer types, with PE being dominant. Furthermore, a negative correlation between specific polymers such as PVC and PET and the normalized weight of the testis was observed. These findings highlight the pervasive presence of microplastics in the male reproductive system in both canine and human testes, with potential consequences on male fertility.

Short-term male reproductive toxicity study with sulfasalazine in the rat

(1) Background: In recent decades, the prevalence of obesity has grown rapidly worldwide, thus causing many diseases, including male hypogonadism. Sulforaphane (SFN), an isothiocyanate compound, has been reported to protect the reproductive system. This research investigated the protective effect of SFN against obesity-induced impairment in the male reproductive system and explored the potential mechanism involved in mice. (2) Methods: One hundred thirty mice were divided into 5 groups (Control, DIO (diet-induced obesity), DIO + SFN 5 mg/kg, DIO + SFN 10 mg/kg, and DIO + SFN 20 mg/kg). The effects of SFN on the male reproductive system were determined based on the sperm count and motility, relative testes and epididymis weights, hormone levels, and pathological analyses. Oxidative stress was determined by measuring malondialdehyde (MDA), total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione (GSH), H2O2, catalase (CAT), and glutathione peroxidase (GSH-PX) levels. Protein expression of nuclear factor erythroid-2 related factor 2 (Nrf2), Kelch-like ECH-associated protein-1 (Keap1), Microtubule-associated protein light chain 3 (LC3), Beclin1, and P62 were determined by western blotting. (3) Results: High-fat diet (HFD)-induced obesity significantly decreased relative testes and epididymis weights, sperm count and motility, and testosterone levels but increased leptin and estradiol levels. SFN supplementation ameliorated these effects. Additionally, SFN administration inhibited the obesity-induced MDA accumulation and increased the SOD level. Western blot indicated that SFN had an important role in the downregulation of Keap1. Moreover, SFN treatment attenuated obesity-induced autophagy, as detected by LC3 and Beclin1. (4) Conclusions: SFN ameliorated the reproductive toxicity associated with obesity by inhibiting oxidative stress mediated by the nuclear factor erythroid-2 related factor 2/ antioxidant response element (Nrf2/ARE) signaling pathway and recovery of normal autophagy.

Rhyacichthys aspro is a “basal” taxon in the Suborder Gobioidei of the teleost order Gobiiformes. We provide detailed descriptions of the reproductive morphology of adult males and females to assess the diagnostic reproductive morphological characters of this speciose clade of bony fishes. Female R. aspro are asynchronous spawners: they are able to spawn more than once in a breeding season. Oocytes are inferred to have short attachment filaments. A conspicuous feature of the external anatomy of the reproductive system (RSy) of female R. aspro is an ornate fimbriate pad upon which the urogenital papilla rests. The male reproductive system is characterized by an intralobar collection system in both the testicular and secretory lobes, termed the “sperm‐collecting canal” and “milt‐collecting canal,” respectively. These may provide additional storage for sperm and milt. The spermatogenic lobe, or testis, is that portion of the male gobioid RSy comprising seminiferous lobules and separate from other RSy components. The secretory lobe is that portion of the male gobioid reproductive system that consists of secretory lobules and is separated from other components of the male RSy. The secretory lobe has also been called, in English, the sperm‐duct gland, accessory gonadal structure, or seminal vesicle, and is endorsed as a synapomorphy of gobioid fishes.

Leptin, the product of the ob gene, has emerged recently as a pivotal signal in the regulation of fertility. Although the actions of leptin in the control of reproductive function are thought to be exerted mainly at the hypothalamic level, the potential direct effects of leptin at the pituitary and gonadal level have been poorly characterised. In the present study, we first assessed the ability of leptin to regulate testicular testosterone secretion in vitro. Secondly, we aimed to evaluate whether leptin can modulate basal gonadotrophin and prolactin (PRL) release by incubated hemi-pituitaries from fasted male rats. To attain the first goal, testicular slices from prepubertal and adult rats were incubated with increasing concentrations (10(-9)-10(-7) M) of recombinant leptin. Assuming that in vitro testicular responsiveness to leptin may be dependent on the background leptin levels, testicular tissue from both food-deprived and normally-fed animals was used. Furthermore, leptin modulation of stimulated testosterone secretion was evaluated by incubation of testicular samples with different doses of leptin in the presence of 10 IU human chorionic gonadotrophin (hCG). In addition, analysis of leptin actions on pituitary function was carried out using hemi-pituitaries from fasted adult male rats incubated in the presence of increasing concentrations (10(-9)-10(-7) M) of recombinant leptin. Serum testosterone levels, and basal and hCG-stimulated testosterone secretion by incubated testicular tissue were significantly decreased by fasting in prepubertal and adult male rats. However, a significant reduction in circulating LH levels was only evident in adult fasted rats. Doses of 10(-9)-10(-7) M leptin had no effect on basal or hCG-stimulated testosterone secretion by testes from prepubertal rats, regardless of the nutritional state of the donor animal. In contrast, leptin significantly decreased basal and hCG-induced testosterone secretion by testes from fasted and fed adult rats. In addition, 10(-9) M leptin inhibited LH and FSH secretion by incubated hemi-pituitaries from fasted adult males, whereas, at all doses tested, it was ineffective in modulating PRL release. Our results show that leptin, depending on the state of sexual maturation, is able to inhibit testosterone secretion acting at the testicular level. Furthermore, the present data suggest that the actions of leptin on the reproductive system are complex and are probably carried out at different levels of the hypothalamic-pituitary-gonadal axis.

Background: The enhancement of male reproductive health function remains a paramount desire of every infertile men. Green coconut water (GCW) is the liquid in the inner cavity of an immature coconut fruit. Studies have demonstrated that GCW has endocrine property that regulates the reproductive system. Aim and Objectives: This study was designed to investigates the effects of GCW on the cardinal sperm function parameters such as; sperm count, sperm motility and sperm morphology, and the histo-architecture of the testis in flutamide-treated pre-pubertal wistar rats. Materials and Methods: Thirty-six male prepubertal wistar rats, weighing between 40-70g were divided into six study groups A-F. Group A, B and C received distilled water, flutamide at 25mg/kg and GCW at 20ml/kg respectively for 6 weeks. Group D and E received 25mg/kg flutamide for 2 weeks then GCW at 10ml/kg and 20ml/kg respectively 4 weeks, while Group F received 25mg/kg flutamide and GCW at 20ml/kg concomitantly for 6 weeks. At the end of the experiment, the animals were euthanized; caudal epididymis and the testis were collected for semen analysis and histological evaluation. Results: GCW supplementation was showed to significantly increased sperm count, sperm motility and also brings about percentage decrease in sperm morphology, as well as ameliorates histo-pathological degenerations caused by flutamide on the testis of the experimental rats. Conclusion: The findings from this study suggest that GCW supplementation may effectively enhance male fertility.

Parabens are alkyl ester compounds of p-hydroxybenzoic acid widely used as preservatives in foodstuffs, cosmetics, toiletries and pharmaceuticals. These compounds are known to exert a weak estrogenic activity in estrogen receptor assays in vitro and in uterotrophic assays in vivo. In this paper, we have shown that butyl paraben had an adverse effect on the male mouse reproductive system and that it damaged the late steps of spermatogenesis in the testis. Butyl paraben was administered to 4-week-old Crj:CD-1 mice assigned to groups of eight animals, at doses of 0.01%, 0.10%, and 1.00% in the diet for 10 weeks. The average butyl paraben intake from the calculated food consumption was 14.4+/-3.60, 146+/-35.9, and 1504+/-357 mg/kg per day for the 0.01%, 0.10%, and 1.00% dietary butyl paraben groups, respectively. There were no treatment-related effects of butyl paraben on the liver, ventral prostates, seminal vesicles, and preputial glands (both in terms of absolute weight and relative to body weight) in any of the study groups. Both the absolute and relative weights of the epididymides were significantly higher in 1.00% group when compared with controls. A dose-dependent decrease of both round and elongated spermatid counts in stages VII-VIII seminiferous tubules was observed, and the elongated spermatid counts were significantly lower in all of the treated groups. The numbers of spermatogonia and spermatocytes did not differ from control values. The serum testosterone concentration decreased in a dose-dependent fashion and was significant at 1.00%. These data demonstrated that butyl paraben can exert an adverse effect on the male reproductive system at doses that are well below those of the accepted daily intake (ADI) in Japan.

Toxicity of polybrominated diphenyl ethers (PBDEs) on rodent male reproductive system: A systematic review and meta-analysis of randomized control studies

The reproductive system is extremely susceptible to environmental insults, for example exogenous steroids during gestational development and differentiation. Experimental induction of androgen excess during prenatal life in female animal models reprograms their reproductive physiology, however the fetal programming of the male reproductive system by androgen excess has not been well studied. We aimed to determine the effect of prenatal exposure of two different doses of testosterone on different gestational days, on the male reproductive system using a rat model. Sixteen pregnant rats were randomly divided into two experimental groups and two control groups. Experimental group І were subcutaneously injected with 3 mg free testosterone on gestational days 16-19 and its controls received solvent for that time; experimental group П were subcutaneously injected with 20 mg free testosterone on day 20 of gestational period and its controls received solvent at the same time. The reproductive system morphology and function of 32 male offspring of these study groups were compared at days 6-30-60 of age and after puberty. The anogenital distance of the male offspring of both experimental groups had no significant differences on the different days of measurement, compared with controls. In the offspring of experimental group І, the testes weight, number of Sertoli, Spermatocyte and Spermatid cells, sperm count and motility and the serum concentration of testosterone after puberty were significantly decreased; except for reduction of sperm motility (p< 0.01), the other effects were not observed in the offspring of experimental group ІІ. In summary, our data show that prenatal exposure of male rat fetuses to excess testosterone disrupted reproductive function, an effect highly dependent on the time, duration and level of exposure. It seems that the reproductive system in individuals exposed to high levels of androgens during fetal life should be evaluated at puberty and likely to be treated.

Alterations in the expression of the human genome, or interference with its products, can be induced in the male reproductive system by chemicals mimicking or antagonizing naturally occurring hormones. Opportunities exist for disruption at the hypothalamus, pituitary and testis levels. Recent concerns generated by the increased incidence of testicular cancer, congenital anomalies of the male genitalia and possible alterations in human semen quality have been linked to the environment. The report by Carlsen in 1992 [1] suggested that semen quality has deteriorated over the past six decades. More recent reports suggest that the decline may be globally non-uniform and regional in nature. The effects of any such declines upon overall pregnancy rates are generally unknown, although some studies have attempted to address them. A preliminary review of the impact of a small decrease in sperm concentrations suggests that a directly measurable reduction in fecundity does not occur, but that future problems could be anticipated. Decrements in semen quality will alter the epidemiological probabilities of pregnancy due to coitus on different cycle days and may thereby change the duration of the fertile time. Current understanding of the implications of altered semen quality on relative fertility is not sufficient to change our current teaching and practice of NFP.

Bisphenol A (BPA) is widely used in manufacturing industries. It is commonly detected in the environment and was reported to exert oestrogenic effects which may be harmful to the reproductive system. The present study was carried out to observe the effects of oral administration of BPA on the development of the reproductive organs and plasma sex hormone levels in prepubertal male Sprague-Dawley (SD) rats. Prepubertal male SD rats (n=8 in each group) were administered BPA in the doses of 1, 5, 10 and 100 mg/kg BW (body weight) via oral gavage for a period of 6 weeks. The control animals received the vehicle for BPA (Tween 80 in distilled water). Following 6 weeks of BPA exposure, the rats exhibited less evidence of spermatogenesis. There was seminiferous epithelial damage which included disruption of intercellular junctions and sloughing of germ cells into the seminiferous tubular lumen. Furthermore, the lumina of the seminiferous tubules and the epididymis of these animals were filled with immature germ cells and cellular debris. This damage may lead to the significant reduction in the seminiferous tubular diameter in BPA-treated animals. These findings were associated with the significant lower plasma testosterone and 17β-oestradiol levels. There was no significant difference between the body weight gain, the absolute as well as relative testis weight or epididymal weight of BPA-treated animals when compared to the control animals. The findings provided further evidence of the detrimental effects of BPA on the male reproductive system.

Bisphenol A is widely used as a material for the production of epoxy resins and polycarbonate plastics. It contaminates various food stuffs by getting leached out from their container lining. Limited information is available on its effects on the male reproductive system. The aim of the present study was to evaluate the extent to which bisphenol A can affect the reproductive system by measuring biochemical and histological changes in the epididymis. Inbred Swiss strain male albino mice were orally administered 80, 120 and 240 mg/kg body weight/day of BPA for 45 days. After completion of treatment, the animals were sacrificed; cauda epididymis was isolated, weighed, used for biochemical and histopathological studies. The results revealed that BPA administered for 45 days caused significant (p<0.05) and dose-dependent reduction in epididymis weight. There was significant (p<0.05) increase in lipid peroxidation and the acid phosphatase activity. Dose dependent reduction in protein, sialic acid contents, as well as the activity of enzymatic antioxidants and mitochondrial enzymes was recorded compared to vehicle treated group. The effect was dose-dependent. Histopathological alteration was observed. This study concludes that BPA causes toxicity in epididymis of mice by generating free radicals, which may be a possible reason for reduction in sperm parameters.

Problem statement: Urtica pilulifera L. (Urticaceae), has long been used for the treatment of various aliments including diabetes. Diabetes is a metabolic disorder characterized by hyperglycemia which has a deleterious effect on all systems including reproductive system of animals. Therefore, the current study was designed to investigate the effects of Urtica pilulifera on the reproductive system of diabetic rats. Approach: Forty male rats were evenly divided into four groups: Group I consisted of non-diabetic rats that received only the vehicle; group II-IV was injected intraperitonially with a single dose of streptozotocin (STZ) of 70 mg kg-1; groups III and IV were given methanol extract of Urtica pilulifera orally, 3 days after the STZ injection, at daily doses of 1.0 and 2.0 g kg-1, respectively. After 4 weeks of treatments, all the rats were sacrificed. Results: Administration of 70 mg kg-1 of streptozotocin to male rats induced diabetes and significantly reduced the body and sex organ weights, testosterone levels, sperm count and motility and significantly increased the glucose levels and water and food intake. By contrast, rats given the Uritica pilulifera methanol extract had significantly improved body weight gain, whereas the glucose levels, water and food intake significantly improved in treated diabetic male rats. In addition, this extract improved the reproductive system of the diabetic male rats by significantly increasing the testis and epididymis weights, testosterone levels, sperm count and motility. Conclusion/Recommendations: We concluded that the adverse effects of STZ-diabetes on reproductive system of male rats can be reversed by treatment with Urtica pilulifera leaf extract; and this leaf extract exhibits antihyperglycemic and spermatogenic activities. Based on these findings, we suggested the possible utilization of Urtica pilulifera extracted as a therapy to prevent the development of diabetes in later life and improved the performance of male reproductive system in animals and humans.

Caesalpinia ferrea Mart (Leguminosae) is a medicinal plant used to treat diabetes, among other therapeutic properties, but which is also reported to have hepatotoxic effects. Although it contains substances such as flavonoids and coumarin, which are known to have antifertility activity, no studies have apparently been conducted to evaluate the potential adverse side effects of this plant on the function of the reproductive system after a chronic treatment. Therefore, this investigation was carried out to evaluate the effect and safety of the long-term exposure to C. ferrea on male Wistar rats' vital organs, reproductive system and sperm production. Adult and immature male rats were treated with an aqueous extract of C. ferrea at a dose level of 300 mg/kg of body weight, administered during one or two spermatogenic cycles of this species. The reproductive and vital organs were analyzed, and sperm was collected from the epididymal secretion of the right epididymis cauda. The long-term administration of C. ferrea did not significantly alter the body, vital and reproductive organs weights. Gamete production was not affected either. The chronic assessment of C. ferrea suggests that this plant does not affect the normal functioning of the Wistar rat reproductive system.

Effect of melatonin on epididymal sperm quality after testicular ischemia/reperfusion in rats