Global warming and glyphosate toxicity (I): Adult zebrafish modelling with behavioural, immunohistochemical and metabolomic approaches

Environmental concentrations of glyphosate through direct or parental exposure alter nervous system development and reduce the fertility rate in zebrafish

N-(phosphonomethyl)glycine (glyphosate) is the most widely used herbicide worldwide. Although it has been extensively studied, few studies use realistic environmental concentrations to assess its potential effects on fish embryos and larvae. This work aims to evaluate potential neurotoxic and reproductive effects of realistic concentrations of glyphosate in non-target aquatic species using zebrafish larvae. Biological and reproductive biomarkers (condition factor, hepatic and gonadic indices, and fertility rate) were evaluated for adults exposed to 0, 10, 100, and 1000 µg/L, while a transcriptomic comparison was carried out for larvae from both exposure scenarios at 1000 µg/L. The fertility rate of exposed parents decreased with increasing glyphosate concentration, while gonadosomatic (GSI) and hepatosomatic (HIS) indices of females treated with 100 µg/L glyphosate were significantly higher in glyphosate-exposed fish compared to the control group; however, glyphosate treatment did not significantly change GSI or HSI in males. Transcriptomic analysis in larvae showed that glyphosate could alter developmental and metabolic processes, targeting the nervous system in both exposure schemes. The ability of glyphosate to alter the development of the nervous system in larvae of exposed parents suggests that exposure to gametes could produce intergenerational alterations, with potential ecotoxicological implications that remain to be determined.

Ecotoxicological mechanism of glyphosate on Moerella iridescens: Evidence from enzyme, histology and metabolome

This study aimed to elucidate the regulatory mechanisms underlying the toxic effects of glyphosate (GLY) on rainbow clam (M. iridescens), with implications for their culture and conservation. GLY residues in aquatic systems raise significant environmental and public health concerns, yet the underlying mechanisms remain largely elusive. In this study, M. iridescens were acutely exposed to GLY at various concentrations (0, 2.34, 5.45, 12.74, 29.74, and 69.46 mg/L) for 7 days. Gill and hepatopancreas samples were collected to assess oxidative stress status and histopathological examination. Additionally, three concentration groups low concentration (LC) group at 2.34 mg/L, medium concentration (MC) group at 12.74 mg/L, and high concentration (HC) group at 69.46 mg/L were selected for metabolomic analysis. The findings indicated that GLY exposure led to oxidative stress and structural changes in tissues. The metabolomic analysis suggested that GLY exposure exacerbates inflammatory responses and disrupts endocrine function, and sex hormones.

The relationship between urinary glyphosate and all-cause and specific-cause mortality: a prospective study

Glyphosate (GLY) is a well-known herbicide with significant applications in both agriculture and non-agriculture. However, GLY overuse in recent years has resulted in detection of GLY residues in many crops, endangering human health and food safety. Our aim is to investigate the relationship between urinary GLY and mortality, as well as its influencing factors. The National Health and Nutrition Examination Survey (NHANES) data from 4740 American adults were examined. Fitted smooth curves, generalized summation models, and multiple logistic regression models were used to investigate the relationship between urinary GLY and mortality. To investigate potential regulatory elements between the two effects, perform subgroup analysis. During a median follow-up of 4.03 years, there were a total of 238 all-cause deaths, 75 cardiovascular disease (CVD) deaths and 52 cancer deaths. The urinary GLY is positively correlated with all-cause mortality. Each 1 ng/ml increase in urinary GLY was associated with a 40% increased risk of all-cause mortality (Hazard ratio (HR) 1.40, 95% confidence interval (CI) 1.09-1.80), and an 50% increased risk of all-cause mortality in High group compared with Low group (HR 1.50, 95% CI 1.05-2.14). In subgroup analysis, the association between urinary GLY and all-cause mortality was significantly modified by gender (P for interaction = 0.03), and the association between urinary GLY and cancer mortality was significantly modified by hypertension (P for interaction = 0.022). Higher urinary GLY seems to be associated with more all-cause death, and gender may affect this association. Furthermore, urine GLY may have a higher effect on cancer mortality in people without hypertension.

Gallic acid's protective mechanisms against acrylamide-induced pulmonary injury: in vivo and in silico insights into the Nrf-2/HO-1/NFκB pathway modulation

Acrylamide (ACR) is a toxic compound formed during the heating of tobacco and starchy foods, contributing to increased reactive oxygen species (ROS) levels and significant health risks. This study evaluates the protective effects of gallic acid (GA), a natural polyphenol with potent antioxidant and anti-inflammatory properties, against ACR-induced lung injury. Fifty male rats were divided into five groups: Control, ACR, GA50 + ACR, GA100 + ACR, and GA100. Lung tissues were analyzed biochemically, histopathologically, immunohistochemically, and via immunofluorescence. GA exhibited dose-dependent protective effects by enhancing antioxidant defenses through Nrf-2 (43% increase) and HO-1 activation and reducing lipid peroxidation markers (MDA decreased by 38%). GA also suppressed pro-inflammatory mediators (TNF-α reduced by 35%) and restored anti-inflammatory levels by modulating the NF-κB pathway. Furthermore, GA reduced apoptosis (Caspase-3 activity decreased by 30%) and preserved lung tissue integrity by mitigating oxidative DNA damage (8-OHdG levels reduced by 29%) and pro-apoptotic signaling (Bax levels reduced by 34%). Computational analyses demonstrated GA's interaction with the KEAP1 protein, supporting its role in activating the KEAP1-Nrf2 pathway. These findings highlight GA's antioxidant, anti-inflammatory, and anti-apoptotic properties, suggesting its therapeutic potential for protecting against ACR-induced lung injury and paving the way for future research in lung health and toxicology.

Enantioselective disruption of circadian rhythm behavior in goldfish (Carassius auratus) induced by chiral fungicide triadimefon at environmentally-relevant concentration

The pollution of triadimefon (TDF) fungicides significantly hinders the "One Health" frame achievement. However, the enantioselective effects of chiral TDF on the circadian rhythm of fish remained unclear. Herein, TDF enantiomers (R(-)-TDF and S(+)-TDF) and racemic Rac-TDF were selected to investigate their enantioselective effects and mechanisms on circadian rhythm of goldfish (Carassius auratus) at an environmentally-relevant concentration (100 µg L⁻¹). S(+)-TDF reduced the diurnal-nocturnal differences in schooling behavior more strongly than R(-)-TDF, proving the enantioselectively weakened circadian rhythm of goldfish by TDF. S(+)-TDF more preferentially bioaccumulated in goldfish than R(-)-TDF, mainly contributed to the enantioselectively disrupted circadian rhythm. On one hand, TDF enantiomers in brains differentially inhibited neuronal activity, leading to cholinergic system dysfunction. On the other hand, TDF enantiomers in intestines differentially disrupted intestinal barriers, thus potentially dysregulating the "brain-gut" axis. Importantly, the commercial probiotics alleviated the behavioral disorder, indirectly confirming that the dysbiosis of intestinal bacteria contributed to the TDF-induced circadian rhythm disruption. These findings provide novel insights into the enantioselective disruption of fish circadian rhythm behaviors by chiral fungicides at enantiomer levels, and offer novel strategies for early assessing the ecological risks of chiral agrochemicals in aquatic ecosystems.

The combined effect of environmentally relevant doses of glyphosate and high temperature: An integrated and multibiomarker approach to delineate redox status and behavior in Danio rerio

Glyphosate, a pesticide commonly found in aquatic ecosystems, affects this habitat and nontarget organisms such as fish. The increase in water temperature, linked to factors such as climate change, poses a considerable threat. Despite extensive ecotoxicological research, we still do not know the real individual and specific consequences of continued exposure to glyphosate and high temperatures, simulating a scenario where the aquatic environment remains contaminated and temperatures continue to rise. Therefore, in this study, we examined the effects of exposure to environmentally relevant concentrations of glyphosate, active ingredient glyphosate (GAI), and glyphosate-based herbicide (GBH) in combination with high temperature (34 °C) in adult zebrafish (Danio rerio). The fish were acclimated to 28 or 34 °C for 96 h. The exposure to 225 and 450 μg L-1 (GBH or GAI) at 28 or 34 °C for 7 days. We analyzed behavioral endpoints (anxiety-like response, sociability, and aggressivity) and biochemical biomarkers of the brain and muscle (oxidative stress). Anxiety-like responses and decreased sociability were disrupted by the combination of glyphosate and high temperature. Furthermore, there is a decrease in Acetylcholinesterase activity in the brain, and an increase in Lipid Peroxidation, Protein Carbonylation, Acetylcholinesterase activity, and Glutathione S-Transferase activity in the muscle. These results demonstrated oxidative stress, anxiety-like behavior and decreased sociability caused by glyphosate and high temperature. We concluded that the combined effects of glyphosate and high temperature affected redox homeostasis and behavior, emphasizing that the field of glyphosate pollution should be carefully considered when evaluating the effects of climate change.

Impact of polyvinyl chloride nano-plastics on the biochemical status of Oreochromis niloticus under a predicted global warming scenario

Plastic pollution and global warming are widespread issues that lead to several impacts on aquatic organisms. Despite harmful studies on both subjects, there are few studies on how temperature increases plastics' adverse effects on aquatic animals, mainly freshwater species. So, this study aims to clarify the potential impact of temperature increases on the toxicological properties of polyvinyl chloride nano-plastics (PVC-NPs) in Nile tilapia (Oreochromis niloticus) by measuring biochemical and oxidative biomarkers. The fish groups were subjected to three distinct temperatures (30, 32, and 34 °C) and subsequently separated into two groups: 0 and 10 mg/L of PVC-NPs, as it is expected that these temperatures may modify their chemical properties, which can influence their absorption and toxicity in fish. After 4 days, the biochemical response of fish exposed to PVC-NPs and elevated temperatures showed a significant increase in the levels of plasma total proteins, albumin, globulin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatinine, and uric acid. Additionally, the level of oxidative stress biomarkers in the liver, gills, and brain was found to have a significant increase in malondialdehyde (MDA) concentration and a decrease in glutathione reduced (GSH) concentration and catalase (CAT) activity in all studied groups. Finally, the current findings revealed a synergistic cytotoxic effect of PVC-NPs and temperatures on the metabolic and oxidative stress indices of O. niloticus.

Differential TLR2 and TLR4 mediated inflammatory and apoptotic responses in asymptomatic and symptomatic Leptospira interrogans infections in canine uterine tissue

Leptospirosis is major zoonotic disease with global implications, affecting both domestic animals and humans. It is caused by Leptospira interrogans (L. interrogans), which can damage multiple organs, including the kidneys, liver, testes, and uterus. Despite this, L. interrogans can also persist asymptomatically in tissues, akin to nonpathogenic strains. The mechanisms driving asymptomatic infections remain poorly understood. This study investigated the role of L. interrogans in asymptomatic infection within the uterine tissue of canines, focusing on the differential expression of Toll-like receptors (TLRs)2 and 4 and their roles in inflammatory and apoptotic pathways. We hypothesized that TLR2 and TLR4 coexpression is crucial for eliciting inflammation and apoptosis, whereas TLR4 alone might be insufficient. Our findings revealed that in symptomatic infections, both TLR2 and TLR4 are coexpressed, leading to markedly elevated levels of the proinflammatory cytokines IL-10, IL-1β, TNF-α, and IL-6. This enhanced inflammatory response is further evidenced by increased CD4 expression, indicating robust T helper cell activation. In contrast, asymptomatic infections are characterized by exclusive TLR4 expression, with inflammatory markers remaining at baseline levels. Additionally, we observed that L. interrogans induces apoptosis in symptomatic animals through TLR2 and TLR4 mediated activation of Caspase 8 and Caspase 3. These findings illustrate that L. interrogans drives both inflammation and apoptosis via the combination of TLR2 and TLR4 actions. When only TLR4 is activated, the immune response is insufficient, resulting in an asymptomatic disease course. This study provides novel insights into the differential roles of TLR receptors in leptospirosis, offering potential directions for targeted therapeutic strategies.

Insights into the enhanced adsorption of glyphosate by dissolved organic matter in farmland Mollisol: effects and mechanisms of action

Dissolved organic matter (DOM) is easy to combine with residual pesticides and affect their morphology and environmental behavior. Given that the binding mechanism between DOM and the typical herbicide glyphosate in soil is not yet clear, this study used adsorption experiments, multispectral techniques, density functional theory, and pot experiments to reveal the interaction mechanism between DOM and glyphosate on Mollisol in farmland and their impact on the environment. The results show that the adsorption of glyphosate by Mollisol is a multilayer heterogeneous chemical adsorption process. After adding DOM, due to the early formation of DOM and glyphosate complex, the adsorption process gradually became dominated by single-layer chemical adsorption, and the adsorption capacity increased by 1.06 times. Glyphosate can quench the endogenous fluorescence of humic substances through a static quenching process dominated by hydrogen bonds and van der Waals forces, and instead enhance the fluorescence intensity of protein substances by affecting the molecular environment of protein molecules. The binding of glyphosate to protein is earlier, of which affinity stronger than that of humic acid. In this process, two main functional groups (C-O in aromatic groups and C-O in alcohols, ethers and esters) exist at the binding sites of glyphosate and DOM. Moreover, the complexation of DOM and glyphosate can effectively alleviate the negative impact of glyphosate on the soil. This study has certain theoretical guidance significance for understanding the environmental behavior of glyphosate and improving the sustainable utilization of Mollisol.

Investigation of the Effects of Boric Acid against Post Operative Testicular Adhesion Caused by Experimental Laporotomy in Rats

Post-operative intra-abdominal adhesions, significantly affecting testicular tissue, are a prevalent and serious complication following laparoscopic surgery. This study investigated the efficacy of boric acid, known for its antioxidant, anti-inflammatory, and anti-apoptotic properties, in preventing post-operative testicular adhesions. Forty rats, were divided into four groups: control, laparoscopy (LA), boric acid (BA), and LA + BA. Following laparoscopic surgery, BA treatment was administered for seven days. While the adhesion score was around 3 in the LA group, it was 1 or below in the LA + BA group. Testicular tissues were examined by histopathological and biochemical methods. In testis tissues, in the LA group, malondialdehyde (MDA) levels increased while superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) levels decreased; these parameters normalized with BA treatment. Additionally, the LA group exhibited reduced levels of IL-10, Bcl-2, Kisspeptin-1, and GnRH, alongside elevated levels of inflammatory markers IL-1β, IL-6, TNF-α, JNK, BAX, and Caspase 3. BA treatment significantly restored these levels to normal. In conclusion, oxidative stress, inflammation, and apoptosis in testicular tissues were associated with post-operative testicular adhesions. BA demonstrated potential as an anti-adhesive agent, reducing testicular adhesions and normalizing biochemical and histological parameters following laparoscopic surgery.

Local thermal adaption mediates the sensitivity of Daphnia magna to nanoplastics under global warming scenarios

The toxicity of nanoplastics at environmentally relevant concentrations has received widespread attention in the context of global warming. Despite numerous studies on the impact of mean temperature (MT), the effects of daily temperature fluctuations (DTFs) on the ecotoxicity of nanoplastics remains largely unexplored. Moreover, the role of evolutionary adaptation in assessing long-term ecological risks is unclear. Here, we investigated the effects of polystyrene nanoplastics (5 μg L-1) on Daphnia magna under varying MT (20 °C and 24 °C) and DTFs (0 °C, 5 °C, and 10 °C). Capitalizing on a space-for-time substitution approach, we further assessed how local thermal adaptation affect the sensitivity of Daphnia to nanoplastics under global warming. Our results indicated that nanoplastics exposure in general reduced heartbeat rate, thoracic limb activity and feeding rate, and increased CytP450, ETS activity and Hgb concentrations. Higher MT and DTFs enhanced these effects. Notably, clones originating from their respective sites performed better under their native temperature conditions, indicating local thermal adaptation. Warm-adapted low-latitude D. magna showed stronger nanoplastics-induced increases in CytP450, ETS activity and Hgb concentrations under local MT 24 °C, while cold-adapted high-latitude D. magna showed stronger nanoplastics-induced decreases in heartbeat rate, thoracic limb activity and feeding rate under high MT than under low MT.

Molecular insights into the antioxidative and anti-inflammatory effects of P-coumaric acid against bisphenol A-induced testicular injury: In vivo and in silico studies

This study investigated the protective effects of p-coumaric acid (PCA) against bisphenol A (BPA)-induced testicular toxicity in male rats. The rats were divided into control, BPA, BPA+PCA50, BPA+PCA100, and PCA100 groups. Following a 14-day treatment period, various analyses were conducted on epididymal sperm quality and testicular tissues. PCA exhibited dose-dependent cytoprotective, antioxidant, and anti-inflammatory effects, ameliorating the decline in sperm quality induced by BPA. The treatment elevated antioxidant enzyme activities (SOD, GPx, CAT) and restored redox homeostasis by increasing cellular glutathione (GSH) and reducing malondialdehyde (MDA) levels. PCA also mitigated BPA-induced proinflammatory responses while reinstating anti-inflammatory IL-10 levels. Apoptotic parameters (p53 and p38-MAPK) were normalized by PCA in BPA-treated testicular tissue. Immunohistochemical and immunofluorescent analyses confirmed the cytoprotective and anti-inflammatory effects of PCA, evidenced by the upregulation of HO-1, Bcl-2, and Nrf-2 and the downregulation of the proapoptotic gene Bax in BPA-induced testicular intoxication. PCA corrected the disturbance in male reproductive hormone levels and reinstated testosterone biosynthetic capacity after BPA-induced testicular insult. In silico analyses suggested PCA's potential modulation of the oxidative stress KEAP1/NRF2/ARE pathway, affirming BPA's inhibitory impact on P450scc. This study elucidates BPA's molecular disruption of testosterone biosynthesis and highlights PCA's therapeutic potential in mitigating BPA's adverse effects on testicular function, showcasing its cytoprotective, anti-inflammatory, and hormone-regulating properties. The integrated in vivo and in silico approach offers a comprehensive understanding of complex mechanisms, paving the way for future research in reproductive health and toxicology, and underscores the importance of employing BPA-free plastic wares in semen handling.

Elucidating the toxicity mechanisms of organophosphate esters by adverse outcome pathway network

With the widespread use of organophosphate esters (OPEs), the accumulation and toxicity effect of OPEs in biota are attracting more and more concern. In order to clarify the mechanism of toxicity of OPEs to organisms, this study reviewed the OPEs toxicity and systematically identified the mechanism of OPEs toxicity under the framework of adverse outcome pathway (AOP). OPEs were divided into three groups (alkyl-OPEs, aryl-OPEs, and halogenated-OPEs) and biota was divided into aquatic organism and mammals. The results showed that tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) mainly caused neurotoxicity, reproductive, and hepatotoxicity in different mechanisms. According to the constructed AOP network, the toxicity mechanism of OPEs on aquatic organisms and mammals is different, which is mainly attributed to the different biological metabolic systems of aquatic organisms and mammals. Interestingly, our results indicate that the toxicity effect of the three kinds of OPEs on aquatic organisms is different, while there was no obvious difference in the mechanism of toxicity of OPEs on mammals. This study provides a theoretical basis for OPEs risk assessment in the future.

Glyphosate-based herbicide (GBH) challenged thermoregulation in lizards (Eremias argus), compensatory warming could mitigate this effect

Chemical pollution and global warming are two major threats to reptiles, and these two factors can interact with each other. Glyphosate have attracted worldwide attention due to their ubiquitous occurrence, yet their impact on reptiles remains unknown. We designed a crossover experiment with different external GBH exposures (control/GBH) x different environmental temperatures (current climate treatment/warmer climate treatment) over 60 days to simulate environmental exposure in the Mongolian Racerunner lizard (Eremias argus). Preferred body temperature and active body temperature data were collected to calculate the accuracy of thermoregulation, while liver detoxification metabolic enzymes, oxidative stress system function, and the non-targeted metabolome of the brain tissue were assessed. Warmer-treated lizards adjusted their physiological levels and behavioral strategies in response to increased ambient temperatures and maintained body temperature homeostasis at moderate thermal perturbations. GBH-treated lizards suffered from oxidative damage to the brain tissue and abnormal histidine metabolism, thus their thermoregulatory accuracy reduced. Interestingly, at elevated ambient temperatures, GBH treatment did not affect on their thermoregulatory, possibly through several temperature-dependent detoxification mechanisms. Importantly, this data suggested that the subtle toxicological effects of GBH may threaten increasingly thermoregulation behavior of E. argus with species-wide repercussions, as climate change and exposure time extension.

Toxicity effects of pesticides based on zebrafish (Danio rerio) models: Advances and perspectives

Pesticides inevitably enter aquatic environments, posing potential risks to organisms. The common aquatic model organism, zebrafish (Danio rerio), are widely used to evaluate the toxicity of pesticides. In this review, we searched the Web of Science database for articles published between 2012 and 2022, using the keywords "pesticide", "zebrafish", and "toxicity", retrieving 618 publications. Furthermore, we described the main pathways by which pesticides enter aquatic environments and the fate of their residues in these environments. We systematically reviewed the toxicity effects of pesticides on zebrafish, including developmental toxicity, endocrine-disrupting effects, reproductive toxicity, neurotoxicity, immunotoxicity, and genotoxicity. Importantly, we summarized the latest research progress on the toxicity mechanism of pesticides to zebrafish based on omics technologies, including transcriptomics, metabolomics, and microbiomics. Finally, we discussed future research prospects, focusing on the combined exposure of multiple pollutants including pesticides, the risk of multigenerational exposure to pesticides, and the chronic toxicity of aquatic nanopesticides. This review provides essential data support for ecological risk assessments of pesticides in aquatic environments, and has implications for water management in the context of pesticide pollution.

Global warming and nanoplastic toxicity; small temperature increases can make gill and liver toxicity more dramatic, which affects fillet quality caused by polystyrene nanoplastics in the adult zebrafish model

Increasing nanoplastics (NPs) pollution may lead to unknown environmental risks when considered together with climate change, which has the potential to become an increasingly important environmental issue in the coming decades. In this context, the present study aimed to evaluate the stressor modelling of polystyrene nanoplastic (PS-NPs) combined with temperature increase in zebrafish. For this purpose, changes in gill, liver and muscle tissues of zebrafish exposed to PS-NPs (25 ppm) and/or different temperatures (28, 29 and 30 °C) for 96 h under static conditions were evaluated. The results obtained emphasize that exposure to PS-NPs stressors under controlled conditions with temperature increase induces DNA damage through stress-induced responses accompanied by degeneration, necrosis and hyperaemia in zebrafish liver and adhesion of lamellae, desquamation and inflammation in lamellar epithelium in gills. Metabolomic analyses also supported changes indicating protein and lipid oxidation, especially PS-NPs-mediated. These findings will contribute to the literature as key data on the effects of PS-NPs presence on protein/lipid oxidation and fillet quality in muscle tissues.

The anxiolytic and circadian regulatory effect of agarwood water extract and its effects on the next generation; zebrafish modelling

Anxiety is one of the most common psychiatric symptoms worldwide. Studies show that there is an increase of >25 % in the prevalence of anxiety with the onset of the COVID-19 pandemic process. Due to the various side effects of drugs used in the treatment of anxiety, interest in natural therapeutic alternatives has increased. Agarwood is a plant used as a natural therapeutic due to its sedative effect as well as many effects such as antioxidant and antibacterial. Although there are many studies with agarwood, comprehensive behavioral studies, including the next generation, are limited. In present study, zebrafish fed with diets containing 10-100 ppm water extract of Agarwood (AWE) for 3 and 8 weeks were exposed to predator stress using Oscar fish in order to test the potential anxiolytic effect of AWE. At the end of the period, zebrafish exposed to predator stress were subjected to anxiety and circadian tests. Histopathological evaluation and immunofluorescent analyzes of BDNF and 5HT4-R proteins were performed in the brains of zebrafish. The effects on the next generation were examined by taking offspring from zebrafish. According to the results, it was observed that AWE had a healing effect on anxiety-like behaviors and on the disrupted circadian rhythm triggered by the predatory stress it applied, especially in the 8 weeks 100 ppm group. Interestingly, it was also found to be effective in offspring of zebrafish fed diets with AWE.

Reproductive Effects of S. boulardii on Sub-Chronic Acetamiprid and Imidacloprid Toxicity in Male Rats

The potential health-promoting effects of probiotics against intoxication by pesticides is a topic of increasing commercial interest with limited scientific evidence. In this study, we aimed to investigate the positive effects of probiotic Saccharomyces boulardii on the male reproductive system under low dose neonicotinoid pesticide exposure conditions. We observed that acetamiprid and imidacloprid caused a degeneration and necrosis of the spermatocytes in the tubular wall, a severe edema of the intertubular region and a hyperemia. This was concomittant to increased levels of 8-hydroxy-2'-deoxyguanosine reflecting oxidative stress, and an increase in caspase 3 expression, reflecting apoptosis. According to our results, Saccharomyces boulardii supplementation mitigates these toxic effects. Further in vivo and clinical studies are needed to clarify the molecular mechanisms of protection. Altogether, our study reinforces the burden of evidence from emerging studies linking the composition of the gut microbiome to the function of the reproductive system.