Reproductive toxicity poses significant risks to fertility and progeny health, making its identification in pharmaceutical compounds crucial. In this study, we conducted a comprehensive in silico investigation of reproductive toxic molecules, identifying three distinct categories represented by Dimethylhydantoin, Phenol, and Dicyclohexyl phthalate. Our analysis included physicochemical properties, target prediction, and KEGG and GO pathway analyses, revealing diverse and complex mechanisms of toxicity. Given the complexity of these mechanisms, traditional molecule-target research approaches proved insufficient. Support Vector Machines (SVMs) combined with molecular descriptors achieved an accuracy of 0.85 in the test dataset, while our custom deep learning model, integrating molecular SMILES and graphs, achieved an accuracy of 0.88 in the test dataset. These models effectively predicted reproductive toxicity, highlighting the potential of computational methods in pharmaceutical safety evaluation. Our study provides a robust framework for utilizing computational methods to enhance the safety evaluation of potential pharmaceutical compounds.

Microplastics (MPs) pollution poses a global environmental challenge with significant concerns regarding its potential impact on human health. Toxicological investigations have revealed multi-system impairments caused by MPs in various organisms. However, the specific reproductive hazards in human contexts remain elusive, and understanding the transgenerational reproductive toxicity of MPs remains limited. This study delves into the reproductive toxicity resulting from lactational exposure to polystyrene MPs (PS-MPs) in female mice, extending the inquiry to assess the reproductive effects on their offspring bred by rigorous natural mating. The MPs dosage corresponds to the detected concentration in infant formula prepared using plastic bottles. By systematically evaluating the reproductive phenotypes of F0 female mice from birth to adulthood, we found that female mice exposed to PS-MPs exhibited delayed puberty, disturbed estrous cyclicity, diminished fertility, elevated testosterone, abnormal follicle development, disrupted ovarian steroidogenesis, and ovarian inflammation. Importantly, the observed inheritable reproductive toxicity manifested with gender specificity, showcasing more pronounced abnormalities in male offspring. Specifically, reproductive disorders did not manifest in female offspring; however, a significant decrease in sperm count and viability was observed in PS-MPs-exposed F1 males. Testicular transcriptomics analysis of F1 males significantly enriched pathways associated with reproductive system development and epigenetic modification, such as male germ cell proliferation, DNA methylation, and histone modification. In summary, real-life exposure to PS-MPs impaired the reproductive function of female mice and threateningly disrupted the spermatogenesis of their F1 male offspring, which raises serious concerns about inter- and trans-generational reproductive toxicities of MPs in mammals. These findings underscore the potential threats of MPs to human reproductive health, emphasizing the need for continued vigilance and research in this critical area.

Carbaryl is widely used as a highly effective insecticide which harms the marine environment. This study aimed to assess the reproductive toxicity of chronic carbaryl exposure on female marine medaka and their female offspring. After a 180-day exposure from embryonic period to adulthood, females exhibited reduced attraction to males, decreased ovulation, increased gonadosomatic index and a higher proportion of mature and atretic follicles. These reproductive toxic effects of carbaryl may stem from changes in hormone levels and transcription levels of key genes along the HPG axis. Furthermore, maternal carbaryl exposure had detrimental effects on the offspring. F1 females showed the reproductive disorders similar to those observed in F0 females. The significant changes in the transcription levels of DNA methyltransferase and demethylase genes in the F0 and F1 generations of ovaries indicate changes in their DNA methylation levels. The changes in DNA methylation levels in F1 female marine medaka may lead to changes in the expression of certain reproductive key genes, such as an increase in the transcription level of cyp19a, which may be the reason for F1 reproductive toxicity. These findings indicate that maternal exposure may induce severe generational toxicity through alterations in DNA methylation levels. This study assesses the negative impacts of whole life-cycle carbaryl exposure on the reproductive and developmental processes of female marine medaka and its female offspring, while offering data to support the evaluation of the ecological risk posed by carbaryl in marine ecosystems.

Benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon, is known to cause teratogenesis. Environmental exposure of BaP has led to wide public concerns due to their potential risk of reproductive toxicity. However, the exact mechanism is still not clear. We aimed to explore the alterations of oxidative stress and DNA hydroxymethylation during BaP-impaired reproductive function. BALB/c mice were intragastrically administered with different doses of BaP (0.01, 0.1, and 1 mg/kg/day, once a day), while control mice were administered with corn coil. Then, the reproductive function, alterations of oxidative stress, DNA methylation, and DNA hydroxymethylation of testis tissues were evaluated. We found that BaP caused obvious histopathological damages of testis tissues. As for sperm parameters after BaP administration, testis weight and the rate of teratosperm were increased, as well as sperm count and motility were decreased. In mechanism, BaP upregulated HO-1 and MDA levels and downregulated SOD and CAT activity and GSH content in testis tissues, indicating that oxidative stress was induced by BaP. Furthermore, a significant induction of hydroxymethylation and inhibition of methylation were observed in testis tissues after BaP exposure. Collectively, BaP-induced oxidative stress and hydroxymethylation were involved in impairing reproductive function, which may be the mechanism of the male infertility.

Tri (2-Ethylhexyl) phosphate (TEHP), widely used as a fire retardant and plasticizer, has been commonly found in the environment. Its potential health-related risks, especially reproductive toxicity, have aroused concern. However, the potential cellular mechanisms remain unexplored. In this study, we aimed to investigate the molecular mechanisms underlying TEHP-caused cell damage in Sertoli cells, which play a crucial role in supporting spermatogenesis. Our findings indicate that TEHP induces apoptosis in 15P-1 mouse Sertoli cells. Subsequently, we conducted RNA sequencing analyses, which suggested that ER stress, autophagy, and MAPK-related pathways may participate in TEHP-induced cytotoxicity. Furthermore, we demonstrated that TEHP triggers ER stress, activates p38 MAPK, and inhibits autophagy flux. Then, we showed that the inhibition of ER stress or p38 MAPK activation attenuates TEHP-induced apoptosis, while the inhibition of autophagy flux is responsible for TEHP-induced apoptosis. These results collectively reveal that TEHP induces ER stress, activates p38, and inhibits autophagy flux, ultimately leading to apoptosis in Sertoli cells. These shed light on the molecular mechanisms underlying TEHP-associated testicular toxicity.

BACKGROUND: Polystyrene nanoplastics (PS-NPs), are ubiquitous pollution sources in human environments, posing significant biosafety and health risks. While recent studies, including our own, have illustrated that PS-NPs can breach the blood-testis barrier and impact germ cells, there remains a gap in understanding their effects on specific spermatogenic cells such as spermatocytes.
RESULTS: Herein, we employed an integrated approach encompassing phenotype, metabolomics, and transcriptomics analyses to assess the molecular impact of PS-NPs on mouse spermatocyte-derived GC-2spd(ts) cells. Optimal exposure conditions were determined as 24 h with 50 nm PS-NPs at 12.5 μg/mL and 90 nm PS-NPs at 50 μg/mL for subsequent multi-omics analysis. Our findings revealed that PS-NPs significantly influenced proliferation and viability, causing alterations in transcriptome and metabolome profiles. Transcriptomics analysis of GC-2spd(ts) cells exposed to PS-NPs indicated the pivotal involvement of cell proliferation and cycle, autophagy, ferroptosis, and redox reaction pathways in PS-NP-induced effects on the proliferation and viability of GC-2spd(ts) cells. Furthermore, metabolomics analysis identified major changes in amino acid metabolism, cyanoamino acid metabolism, and purine and pyrimidine metabolism following PS-NP exposure.
CONCLUSIONS: Our integrated approach, combining metabolomics and transcriptomics profiles with phenotype data, enhances our understanding of the adverse effects of PS-NPs on germ cells.

Bisphenol F (BPF) has been extensively utilized in daily life, which brings new hazards to male reproductive health. However, the specific functional mechanism is still unclear. Both cell and animal models were utilized for exploring the role of RNA methylation and ferroptosis and its underlying mechanisms in male reproductive injury induced by BPF. In animal model, BPF severely destroyed the integrity of the blood-testis barrier (BTB) and induced ferroptosis. Furthermore, BPF significantly affected the barrier function of TM4 cells and promoted ferroptosis. Importantly, ChIP assays revealed that BPF inhibited AR transcriptional regulation of FTO and FTO expression was downregulated in TM4 cells. Overexpression of FTO prevented the impairment of BTB by inhibiting ferroptosis in TM4 cells. Mechanistically, FTO could significantly down-regulate the m6A modification level of TfRc and SLC7A11 mRNA through MeRIP experiment. RIP experiments showed that YTHDF1 can bind to TfRc mRNA and promote its translation while YTHDF2 could bind to SLC7A11 mRNA and reduce its mRNA stability. Therefore, our results suggest that FTO plays a key role in BPF induced male reproductive toxicity through YTHDF1-TfRc axis and YTHDF2-SLC7A11 axis and may provide new ideas and methods for the prevention and treatment of male reproductive diseases associated with environmental pollutants.

Nanoplastics (NPs), as emerging contaminants, have been shown to cause testicular disorders in mammals. However, whether paternal inheritance effects on offspring health are involved in NP-induced reproductive toxicity remains unclear. In this study, we developed a mouse model where male mice were administered 200 nm polyethylene nanoparticles (PE-NPs) at a concentration of 2 mg/L through daily gavage for 35 days to evaluate the intergenerational effects of PE-NPs in an exclusive male-lineage transmission paradigm. We observed that paternal exposure to PE-NPs significantly affected growth phenotypes and sex hormone levels and induced histological damage in the testicular tissue of both F0 and F1 generations. In addition, consistent changes in sperm count, motility, abnormalities, and gene expression related to endoplasmic reticulum stress, sex hormone synthesis, and spermatogenesis were observed across paternal generations. The upregulation of microRNA (miR)-1983 and the downregulation of miR-122-5p, miR-5100, and miR-6240 were observed in both F0 and F1 mice, which may have been influenced by reproductive signaling pathways, as indicated by the RNA sequencing of testis tissues and quantitative real-time polymerase chain reaction findings. Furthermore, alterations in the gut microbiota and subsequent Spearman correlation analysis revealed that an increased abundance of Desulfovibrio (C21_c20) and Ruminococcus (gnavus) and a decreased abundance of Allobaculum were positively associated with spermatogenic dysfunction. These findings were validated in a fecal microbiota transplantation trial. Our results demonstrate that changes in miRNAs and the gut microbiota caused by paternal exposure to PE-NPs mediated intergenerational effects, providing deeper insights into mechanisms underlying the impact of paternal inheritance.

The water accommodated fraction (WAF) of spilled crude oil is a severe threat to the health of marine fish. This study was conducted to investigate the effects of short-term embryonic exposure to the WAF on the ovarian development and reproductive capability of F0 adult female marine medaka (Oryzias melastigma). Following embryonic exposure to the WAF with nominal total petroleum hydrocarbon concentrations of 0.5, 5, 50, and 500 μg/L for 7 days, the number of spawned eggs and gonadosomatic indices of F0 adult females were significantly reduced at 130 days postfertilization. In these F0 adult females, the proportion of mature oocytes was significantly lower, the level of 17β-estradiol was lower, and the level of testosterone was greater than those in control group. The mRNA levels of the follicle-stimulating hormone β subunit, luteinizing hormone β subunit, cytochrome P450 aromatase 19b, estrogen receptor α and β, and androgen receptor α and β genes were upregulated, while the mRNA level of the salmon-type gonadotropin-releasing hormone was downregulated in F0 adult females exposed to the WAF during the embryonic stage. Additionally, the methylation level of vitellogenin (vtg) in F0 adult females was significantly elevated, this might have, in turn, downregulated the mRNA level of vtg. The mortality rate of the unexposed F1 embryos was significantly increased and the hatching success was significantly reduced. These results collectively indicated the necessity of incorporating and evaluating the effects of short-term early-life exposure to crude oil in the assessment of risks to the reproductive health of marine fish.

Ionic liquids (ILs) become emerging environmental pollutants. Especially, alkyl imidazolium ILs commonly showed stimulation in toxicological studies and mechanisms remained to be explored. In the present study, alkyl imidazolium tetrafluoroborate ([amim]BF4), with ethyl ([emim]), hexyl ([hmim]) and octyl ([omim]) as side-chains, were chosen as target ILs. Their toxicities on the reproduction and lifespan of Caenorhabditis elegans were explored with two types (A and B) exposure arrangements to mimic realistic intermittent multi-generational exposure scenarios. In type A scenario, there was an exposure every 4 generations with 12 generations in total, and in type B one, there was an exposure every two generations with 12 generations in total. Result showed that [emim]BF4 caused inhibition on the reproduction in 8 generations in type A exposure but 6 ones in type B exposure. Meanwhile, [hmim]BF4 showed inhibition in one generation and stimulation in 3 generations in type A exposure, but stimulation in 6 generations in type B exposure. Also, [omim]BF4 showed stimulation in one generation in type B exposure. Collectively, the results demonstrated less frequencies of inhibition, or more frequencies of stimulation, in the exposure scenario with more frequent exposures. Further mechanism exploration was performed to measure the lipid storage and metabolism in the aspect of energy supply. Results showed that [emim]BF4, [hmim]BF4 and [omim]BF4 commonly stimulated the triglyceride (TG) levels across generations. They also disturbed the activities of glycerol-3-phosphate acyltransferase (GPAT) and acetyl CoA carboxylase (ACC) in lipogenesis, those of adipose triglyceride lipase (ATGL) and carnitine acyl transferase (CPT) in lipolysis, and also the contents of acetyl-CoA (ACA). Further data analysis indicated the energy allocation among life traits including reproduction, antioxidant responses and hormone regulations.