Possible role for glutathione-S-transferase in the oligozoospermia elicited by acute zearalenone administration in Swiss albino mice

Estrogenic and Non-Estrogenic Disruptor Effect of Zearalenone on Male Reproduction: A Review

According to some estimates, at least 70% of feedstuffs and finished feeds are contaminated with one or more mycotoxins and, due to its significant prevalence, both animals and humans are highly likely to be exposed to these toxins. In addition to health risks, they also cause economic issues. From a healthcare point of view, zearalenone (ZEA) and its derivatives have been shown to exert many negative effects. Specifically, ZEA has hepatotoxicity, immunotoxicity, genotoxicity, carcinogenicity, intestinal toxicity, reproductive toxicity and endocrine disruption effects. Of these effects, male reproductive deterioration and processes that lead to this have been reviewed in this study. Papers are reviewed that demonstrate estrogenic effects of ZEA due to its analogy to estradiol and how these effects may influence male reproductive cells such as spermatozoa, Sertoli cells and Leydig cells. Data that employ epigenetic effects of ZEA are also discussed. We discuss literature data demonstrating that reactive oxygen species formation in ZEA-exposed cells plays a crucial role in diminished spermatogenesis; reduced sperm motility, viability and mitochondrial membrane potential; altered intracellular antioxidant enzyme activities; and increased rates of apoptosis and DNA fragmentation; thereby resulting in reduced pregnancy.

Downregulation of microRNA-96-5p protects TM3 cells against zearalenone toxicity via targeting ATG9A

Male infertility factor accounts for ~50% of all infertility cases, and traditional treatments for male infertility are limited. The association between the dysfunction of Leydig cells and hypospermatogenesis is essential for developing novel treatment methods for male infertility. It was previously stated that elevated expression of microRNA (miR)-96-5p was associated with the toxicological response of Leydig cells to treatment with zearalenone (ZEN). However, the exact role of miR-96-5p in Leydig cells remains to be illustrated. The mouse Leydig cell line TM3 was used in the present study to investigate the role of miR-96-5p. ZEN was used to induce cell injury in TM3 cells. Cell Counting Kit-8 assay and the Ki67 staining method were used to evaluate cell viability. Reverse transcription-quantitative PCR was used to determine the expression levels of miR-96-5p. In addition, a dual luciferase assay was used to investigate the target of miR-96-5p. Annexin V/propidium iodide staining was performed to detect cell apoptosis. Western blot analysis was used to detect the expression levels of certain proteins. Finally, monodansylcadaverine (MDC) and LC3 staining were applied for monitoring the level of autophagy. ZEN inhibited the proliferation of TM3 cells in a dose-dependent manner. In addition, the level of miR-96-5p were significantly increased in ZEN-treated TM3 cells. Meanwhile, inhibition of miR-96-5p could reverse ZEN-induced decrease in viability in TM3 cells. Moreover, ZEN notably inhibited autophagy in TM3 cells and this phenomenon was reversed by the application of the miR-96-5p inhibitor. Autophagy related 9A (ATG9A) was identified as the biological target of miR-96-5p. The results derived from MDC and LC3 staining demonstrated that downregulation of miR-96-5p expression levels protected TM3 cells against ZEN toxicity by regulating autophagy. Inhibition of miR-96-5p expression protected TM3 cells against ZEN via targeting ATG9A. Therefore, miR-96-5p may serve as a potential biomarker for male infertility.

Melatonin alleviates β-zearalenol and HT-2 toxin-induced apoptosis and oxidative stress in bovine ovarian granulosa cells

β-zearalenol (β-zol) and HT-2 are mycotoxins which cause apoptosis and oxidative stress in mammalian reproductive cells. Melatonin is an endogenous antioxidant involved in apoptosis and oxidative stress-related activities. This study investigated the effects of β-zol and HT-2 on bovine ovarian granulosa cells (BGCs), and how melatonin may counteract these effects. β-zol and HT-2 inhibited cell proliferation in a dose-dependent manner, and induced apoptosis of BGCs. They also yielded upregulation of the apoptosis-related genes Bax/Bcl-2 and Caspase3 and phosphorylation of p38MAPK. Increases in intracellular ROS were observed along with higher levels of mRNA anti-oxidation markers SOD1, SOD2, and CAT. SOD1, SOD2, malonaldehyde (MDA), and glutathione peroxidase (GSH-px) activities increased, as did the levels of SOD1 and SOD2 proteins. All of these effects were reduced or entirely attenuated in BGCs pre-treated with melatonin. Our results demonstrate that melatonin has protective effects against mycotoxin-induced apoptosis and oxidative stress in BGCs.

The flavonoid chrysin protects against zearalenone induced reproductive toxicity in male mice

The mycotoxin zearalenone (ZEA) has strong estrogenic effects and elicits reproductive toxicity. Chrysin is a natural flavonoid found in many plant and has a broad range of pharmacological activities, including anticancer, antioxidant and anti-inflammatory. The present study aimed to investigate the potential protective effects of chrysin against ZEA toxicity. Mice received chrysin (5 or 20 mg/kg; i.g.) for ten days, and then received a single injection of ZEA (40 mg/kg). Two days thereafter, blood and testes were collected. ZEA decreased number and motility of sperm, plasma testosterone levels, enzymatic (glutathione peroxidase, glutathione reductase, glutathione-S-transferase) and non-enzimatic defenses (reduced glutathione). Moreover, ZEA increased 4-hydroxynonenal and 8-hydroxy-2'-deoxyguanosine levels, myeloperoxidase activity and levels of proinflammatory cytokines (interleukins-1β and 6, tumor necrosis factor alpha). ZEA also decreased levels of anti-inflammatory cytokine interleukin-10 and increased activity of caspases 3 and 9. Chrysin treatment increased the number and motility of sperm, testosterone levels, restored antioxidant defenses and reduced the inflammation and apoptosis process. In summary, chrysin attenuated the toxic effects caused by ZEA in blood and testes of mice, suggesting a potential preventive treatment against the deleterious effects of ZEA.

Proanthocyanidin protects against acute zearalenone-induced testicular oxidative damage in male mice

Zearalenone (ZEN) exerts a major effect on human and animal health and has led to serious worldwide economic problems. In this study, we investigated whether proanthocyanidin (PC) can prevent ZEN-induced testicular oxidative damage in male mice and explored the underlying mechanism. Kunming mice were injected with ZEN (40 mg kg^-1) on the 11th day after intragastric administration of PC (75 or 150 mg/kg) for 10 days; the sperm quality of mice was then analysed statistically. Additionally, testicular morphology parameters related to oxidative damage, apoptosis and the expression of endoplasmic reticulum (ER) stress-related genes (GRP78, CHOP and XBP-1) were all measured. Results showed that ZEN exposure significantly reduced the sperm density, improved the sperm aberration rate, increased the MDA level and reduced SOD and GSH-Px activities. Meanwhile, ZEN was attributed to the downregulation of the expressions of the gene and protein of Bcl-2 and upregulation of the expressions of the gene and protein of Bax and caspase-3. ZEN exposure also upregulated the mRNA expression of GRP78, CHOP and XBP-1; however, PC pre-treatment reduced ZEN-induced oxidative damage and tended to maintain normal testicular morphology. Furthermore, PC pre-treatment substantially downregulated the expressions of the GRP78, CHOP and XBP-1 and upregulated the expression of the Bcl-2 gene. In conclusion, PC, due to its anti-oxidative ability, could ameliorate ZEN-induced testicular reproductive toxicity in male mice by decreasing ER stress and testicular cell apoptosis.

The Influence of Selenium Yeast on Hematological, Biochemical and Reproductive Hormone Level Changes in Kunming Mice Following Acute Exposure to Zearalenone

Healthy male Kunming mice received selenium yeast for 14 days prior to a single oral administration of zearalenone (ZEN). After 48 h, blood samples were collected for analysis and showed that mice in the ZEN-treated group has significantly decreased lymphocytes (P < 0.05) and platelets (P < 0.05) along with an increased white blood cell (WBC) count and other constituents (P < 0.05). The serum biochemistry analysis of the ZEN group indicated that glutamic pyruvic transaminase (ALT), glutamic oxaloacetic transaminase (AST), urea, and uric acid were significantly increased (P < 0.05), whilst total bilirubin (TB) and albumin (ALB) were decreased along with serum testosterone and estrogen (P < 0. 05). The level of malondialdehyde (MDA) in the serum of the ZEN group was significantly increased whilst glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) had significantly decreased (P < 0.05). Treatment with selenium yeast had a significant effect on response with most of the experimental parameters returning to levels similar to those observed in the untreated control mice. From these data, it can be concluded that ZEN is highly poisonous in Kunming mice with high levels of toxicity on the blood, liver, and kidneys. High levels of oxidative stress were observed in mice and pre-treatment with selenium yeast by oral gavage is effective in the ameliorated effects of ZEN-induced damage.

Anticonvulsant activity of β-caryophyllene against pentylenetetrazol-induced seizures

Increasing evidence suggests that plant-derived extracts and their isolated components are useful for treatment of seizures and, hence, constitute a valuable source of new antiepileptic drugs with improved efficacy and better adverse effect profile. β-Caryophyllene is a natural bicyclic sesquiterpene that occurs in a wide range of plant species and displays a number of biological actions, including neuroprotective activity. In the present study, we tested the hypothesis that β-caryophyllene displays anticonvulsant effects. In addition, we investigated the effect of β-caryophyllene on behavioral parameters and on seizure-induced oxidative stress. Adult C57BL/6 mice received increasing doses of β-caryophyllene (0, 10, 30, or 100mg/kg). After 60 min, we measured the latencies to myoclonic and generalized seizures induced by pentylenetetrazole (PTZ, 60 mg/kg). We found that β-caryophyllene increased the latency to myoclonic jerks induced by PTZ. This result was confirmed by electroencephalographic analysis. In a separate set of experiments, we found that mice treated with an anticonvulsant dose of β-caryophyllene (100mg/kg) displayed an improved recognition index in the object recognition test. This effect was not accompanied by behavioral changes in the open-field, rotarod, or forced swim tests. Administration of an anticonvulsant dose of β-caryophyllene (100mg/kg) did not prevent PTZ-induced oxidative stress (i.e., increase in the levels of thiobarbituric acid-reactive substances or the decrease in nonprotein thiols content). Altogether, the present data suggest that β-caryophyllene displays anticonvulsant activity against seizures induced by PTZ in mice. Since no adverse effects were observed in the same dose range of the anticonvulsant effect, β-caryophyllene should be further evaluated in future development of new anticonvulsant drugs.

Lycopene protects against acute zearalenone-induced oxidative, endocrine, inflammatory and reproductive damages in male mice

Male mice received lycopene for 10 days before a single oral administration of zearalenone (ZEA). After 48 h testes and blood were collected. Mice treated with lycopene/ZEA exhibited amelioration of the hematological changes. Lycopene prevented the reduction in the number and motility of spermatozoa and testosterone levels, indicating a protective effect in the testicular damage induced by ZEA. Lycopene was also effective in protecting against the decrease in glutathione-S-transferase, glutathione peroxidase, glutathione reductase and δ-aminolevulinic acid dehydratase activities caused by ZEA in the testes. Exposure of animals to ZEA induced modification of antioxidant and inflammatory status with increase of reduced glutathione (GSH) levels and increase of the oxidized glutathione, interleukins 1β, 2, 6, 10, tumor necrosis factor-α and bilirubin levels. Lycopene prevented ZEA-induced changes in GSH levels and inhibited the processes of inflammation, reducing the damage induced by ZEA. Altogether, our results indicate that lycopene was able to prevent ZEA-induced damage in the mice.

Lycopene treatment prevents hematological, reproductive and histopathological damage induced by acute zearalenone administration in male Swiss mice

Zearalenone (ZEA) is a mycotoxin commonly found as a contaminant in cereals. ZEA toxicity targets mainly the reproductive system, and oxidative stress plays an etiological role in its toxic effects. Therefore, the present study aimed to investigate the effect of lycopene, a potent carotenoid antioxidant, on markers of oxidative stress in liver, kidney and testes, and on reproductive, hematological and histopathological parameters after ZEA administration. Adult Swiss albino male mice received lycopene (20mg/kg, p.o.) for ten days before a single oral administration of ZEA (40mg/kg, p.o.), and 48h thereafter tissues (liver, kidney, testes and blood) were collected for biochemical, hematological and histological analyses. Lycopene prevented ZEA-induced changes in hematological parameters (increased number of leukocytes, segmented neutrophils, sticks, eosinophils and monocytes and decreased number of red blood cells (RBC), number of lymphocytes and platelets). Moreover, lycopene prevented the reduction in the number and motility of spermatozoa and the testicular tissue damage induced by ZEA. In addition, lycopene prevented the decrease in glutathione-S-transferase activity in kidney and testes and increased glutathione-S-transferase activity per se in the liver, kidneys and testes as well as superoxide dismutase activity in the liver. In summary, lycopene was able to prevent ZEA-induced acute toxic effects in male mice, suggesting that this antioxidant carotenoid may represent a promising prophylactic strategy against ZEA toxicity.