Effect of vitamins C and E on spermatogenesis in mice exposed to cadmium

A metabolomic perspective on the mechanisms by which environmental pollutants and lifestyle lead to male infertility

The incidence of male infertility (MI) is rising annually. According to epidemiological studies, environmental pollution (e.g., organic, inorganic, and air pollutants), occupational exposure (e.g., high temperature, organic solvents, and pesticides), and poor lifestyle (e.g., diet, sleep, smoking, alcohol consumption, and exercise) are important non-genetic causative factors of MI. Due to multiple and complex causative factors, the dose-effect relationship, and the uncertainty of pathogenicity, the pathogenesis of MI is far from fully clarified. Recent data show that the pathogenesis of MI can be monitored by the metabolites in serum, seminal plasma, urine, testicular tissue, sperm, and other biological samples. It is considered that these metabolites are closely related to MI phenotypes and can directly reflect the individual pathological and physiological conditions. Therefore, qualitative and quantitative analysis of the metabolome, the related metabolic pathways, and the identification of biomarkers will help to explore the MI-related metabolic problems and provide valuable insights into its pathogenic mechanisms. Here, we summarized new findings in MI metabolomics biomarkers research and their abnormal metabolic pathways triggered by the presented non-genetic risk factors, providing a metabolic landscape of semen and seminal plasma in general MI patients. Then, we compared the similarities and differences in semen and seminal plasma biomarkers between MI patients exposed to environmental and poor lifestyle factors and MI patients in general, and summarized some common biomarkers. We provide a better understanding of the biological underpinnings of MI pathogenesis, which might offer novel diagnostic, prognostic, and precise treatment approaches to MI.

Involvement of Nrf2-PPAR-γ signaling in Coenzyme Q10 protecting effect against methotrexate-induced testicular oxidative damage

Studies have identified Coenzyme Q10 (CoQ10) as a promising agent in improving idiopathic male infertility; however, its role in chemically or environmentally induced testicular dysfunction is not well-established. We investigated the potential of CoQ10 to attenuate methotrexate (MTX)-induced testicular damage and to identify molecular targets of CoQ10 effects. Wistar rats received a single intraperitoneal dose of 20 mg/kg MTX on the fifth day of the 10-day experimental protocol. 100 mg/kg CoQ10 was given orally daily for ten days, alone or combined with MTX. The testes of MTX-treated animals showed thickened tunica albuginea, distortion of seminiferous tubules with a marked reduction of germinal lining, a few primary spermatocytes with no spermatozoa, apoptotic cells, congested sub-capsular and interstitial blood vessels, and interstitial edema. Reduction of reproductive hormones and increased oxidative, inflammatory, and apoptotic biomarkers levels were also seen in the MTX-treated rats. CoQ10 + MTX-treated rats were protected against MTX-induced testicular histological changes and showed improvement in testosterone, luteinizing-, and follicle-stimulating hormone serum levels compared to the MTX group. The testes of the CoQ10 + MTX-treated rats showed reduced malondialdehyde, myloperoxidase, tumor necrosis factor -α, interleukin-6 and -1β and Bax: Bcl2 ratio and enhanced glutathione, and catalase compared to MTX alone. CoQ10 enhanced MTX-induced downregulation of Nrf2 and PPAR-γ signaling and modulated its downstream targets, the inducible nitric oxide synthase, NF-κB, Bax, and Bcl2. In conclusion, CoQ10 targeted the Nrf2-PPAR-γ signaling loop and its downstream pathways, mitigating MTX-induced oxidative stress-related damages and alleviating the testicular dysfunction MTX caused. Our data suggest Nrf2-PPAR-γ signaling as a potential therapeutic target in testicular toxicity, where oxidative stress, inflammation, and apoptosis trigger damage.

Environmental and occupational exposure to cadmium associated with male reproductive health risk: a systematic review and meta-analysis based on epidemiological evidence

There is an abundance of epidemiological evidence and animal experiments concerning the correlation between cadmium exposure and adverse male reproductive health outcomes. However, the evidence remains inconclusive. We conducted a literature search from PubMed, Embase, and Web of Science over the past 3 decades. Pooled r and 95% confidence intervals (CIs) were derived from Cd levels of the type of biological materials and different outcome indicators to address the large heterogeneity of existing literature. Cd was negatively correlated with semen parameters (r = - 0.122, 95% CI - 0.151 to - 0.092) and positively correlated with sera sex hormones (r = 0.104, 95% CI 0.060 to 0.147). Among them, Cd in three different biological materials (blood, semen, and urine) was negatively correlated with semen parameters, while among sex hormones, only blood and urine were statistically positively correlated. In subgroup analysis, blood Cd was negatively correlated with semen density, sperm motility, sperm morphology, and sperm count. Semen Cd was negatively correlated with semen concentration. As for serum sex hormones, blood Cd had no statistical significance with three hormones, while semen Cd was negatively correlated with testosterone. In summary, cadmium exposure might be associated with the risk of a decline in sperm quality and abnormal levels of sex hormones.

Oxidative Stress and Male Infertility: The Protective Role of Antioxidants

Oxidative stress is a significant factor in male infertility, compromising sperm function and overall reproductive health. As male infertility garners increasing attention, effective therapeutic interventions become paramount. This review investigates the therapeutic role of antioxidants in addressing male infertility. A detailed examination was conducted on antioxidants such as vitamin C, E, B12, D, coenzyme Q10, zinc, folic acid, selenium, l-carnitine, l-arginine, inositols, and alpha-lipoic acid. This analysis examines the methodologies, outcomes, and constraints of current clinical studies. Antioxidants show notable potential in counteracting the negative effects of oxidative stress on sperm. Based on the evidence, these antioxidants, individually or synergistically, can enhance sperm health and reproductive outcomes. However, certain limitations in the studies call for careful interpretation. Antioxidants are integral in tackling male infertility attributed to oxidative stress. The current findings underscore their therapeutic value, yet there's a pressing need for deeper, comprehensive research. Future studies should focus on refining dosage guidelines, identifying potential side effects, and discerning the most efficacious antioxidant combinations for male infertility solutions.

Morin mitigates cadmium-induced testicular impairment by stimulating testosterone secretion and germ cell proliferation in mice

Cadmium (Cd) is one of the heavy metal pollutants present in the environment due to human intervention. It is well known that Cd causes toxicological effects on various organs, including the testes. Morin hydrate is a plant-derived bioflavonoid with antioxidant, anti-inflammatory, and anti-stress properties. Thus, the question can be raised as to whether Morin has an effect on Cd-intoxication-induced testicular impairment. Therefore, the aim of this study was to investigate the role of Morin on Cd-mediated disruption of testicular activity. Mice were divided into three groups: group 1 served as the control group, group 2 was given Cd (10 mg/kg) orally for 35 days, and group 3 was given Cd and Morin hydrate (100 mg/kg) for 35 days. To validate the in vivo findings, an in vitro study on testicular explants was also performed. The results of the in vivo study showed that Cd-intoxicated mice had testicular disorganization, reduced circulating testosterone levels, decreased sperm density, and elevated oxidative stress and sperm abnormality. The expression of the germ cell proliferation marker, germ cell nuclear acidic protein (GCNA), and adipocytokine visfatin were also downregulated. It was observed that Morin hydrate upregulated testicular visfatin and GCNA expression in Cd-intoxicated mice, along with improvement in circulating testosterone, testicular histology, and sperm parameters. Furthermore, the in vitro study showed that Cd-mediated downregulation of testicular visfatin and GCNA expression, along with the suppressed secretion of testosterone from testicular explants, was normalized by Morin treatment, whereas visfatin expression was not. Overall, these data indicate that environmental cadmium exposure impairs testicular activity through downregulation of visfatin and GCNA expression, and Morin might play a protective role against Cd-induced testicular toxicity.

A Review on the Impact of Oxidative Stress and Medicinal Plants on Leydig Cells

Leydig cells are essential for steroidogenesis and spermatogenesis. An imbalance in the production of reactive oxygen species (ROS) and the cellular antioxidant level brings about oxidative stress. Oxidative stress (OS) results in the dysfunction of Leydig cells, thereby impairing steroidogenesis, spermatogenesis, and ultimately, male infertility. To prevent Leydig cells from oxidative insults, there needs to be a balance between the ROS production and the cellular protective capacity of antioxidants. Evidence indicates that medicinal plants could improve Leydig cell function at specific concentrations under basal or OS conditions. The increased usage of medicinal plants has been considered a possible alternative treatment for male infertility. This review aims to provide an overview of the impact of oxidative stress on Leydig cells as well as the effects of various medicinal plant extracts on TM3 Leydig cells. The medicinal plants of interest include Aspalathus linearis, Camellia sinensis, Moringa oleifera, Morinda officinale, Taraxacum officinale, Trichilia emetica, Terminalia sambesiaca, Peltophorum africanum, Ximenia caffra, Serenoa repens, Zingiber officinale, Eugenia jambolana, and a combination of dandelion and fermented rooibos (CRS-10). According to the findings obtained from studies conducted on the evaluated medicinal plants, it can, therefore, be concluded that the medicinal plants maintain the antioxidant profile of Leydig cells under basal conditions and have protective or restorative effects following exposure to oxidative stress. The available data suggest that the protective role exhibited by the evaluated plants may be attributed to their antioxidant content. Additionally, the use of the optimal dosage or concentration of the extracts in the management of oxidative stress is of the utmost importance, and the measurement of their oxidation reduction potential is recommended.

Zinc and selenium attenuate quaternary heavy metal mixture-induced testicular damage via amplification of the antioxidant system, reduction in metal accumulation, inflammatory and apoptotic biomarkers

Heavy metals (HMs) such as cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg) are highly toxic elements. They are often found together in nature as a heavy metal mixture (HMM) and are known to contribute to subfertility/infertility as environmental pollutants. This study aims to evaluate the potential benefits of treating HMM-induced testicular pathophysiology with zinc (Zn) and/or selenium (Se). Six-week-old male Sprague Dawley rats were grouped into 5 (n = 7). The control group received deionized water, while the other groups were treated with PbCl2 (20 mg kg-1), CdCl2 (1.61 mg kg-1), HgCl2 (0.40 mg kg-1), and Na2AsO3 (10 mg kg-1) in deionized water for 60 days. Additionally, groups III to V received Zn, Se, and Zn/Se, respectively, for 60 days. The study evaluated testis weight, metal accumulation, sperm analysis, FSH, LH, testosterone, prolactin, oxidative stress, antioxidants, pro-inflammatory and apoptotic markers, and presented structural changes in the testis as micrographs. HMM caused a significant increase in testis weight, metal accumulation, prolactin, oxidative stress, and pro-inflammatory and apoptotic markers, while significantly decreasing semen analysis, FSH, LH, and testosterone. Histology showed decreased spermatogenesis and spermiogenesis, as evidenced by the structure of the germ cells and spermatids. However, Zn, Se, or both ameliorated and reversed some of the observed damages. This study provides further evidence for the mitigative potential of Zn, Se, or both in reversing the damage inflicted by HMM in the testis, and as a countermeasure towards improving HM-induced decrease in public health fecundity.

Graphical abstract

Age-related histopathological and biochemical testicular damages were ameliorated by vitamin C administration

INTRODUCTION AND OBJECTIVES

Aging is an irreversible process associated with decreased biological functions that can lead to the reduction of reproductive organs capacities in males and females. Paternal age is a significant predictor of offspring health and development. So, the aim of this study was to evaluate the effects of vitamin C on histopathological and biochemical testicular changes following aging process with a focus on stereological methods.

MATERIAL AND METHODS

For this study, 48 adult male NMRI mice were divided into two control and experimental groups. Mice in experimental group were supplemented with vitamin C (150mg/kg) including 24-h interval by oral gavage for 33 weeks. Same regime was performed for animals in control group except that vitamin C was replaced by water. Then, right testes were extracted for stereological and left testes were used for molecular analyses on weeks 8, 12, and 33.

RESULTS

Our findings showed low semen quality, decreased level of serum Luteinizing hormone (LH), Follicle-stimulating hormone (FSH), and testosterone along with increased reactive oxygen species (ROS) production and higher apoptotic gene expression following aging. Stereological studies showed that the volume of testes, the length of seminiferous tubules, and the number of spermatogenic and none-spermatogenic cells decreased significantly during aging. Also, vitamin C consumption for 33 weeks significantly improved biochemical and histological indices. The impact of aging on male reproduction seems to be inevitable worldwide. Therefore, the use of protective and preventive remedies conserving male fecundity is very important and based on our results, vitamin C is a beneficial candidate for improving age-related testicular changes due to aging process.

Vitamin C supplementation rescued meiotic arrest of spermatocytes in Balb/c mice exposed to BDE-209

Deca-brominated diphenyl ether (BDE-209) is a ubiquitous industrial chemical as brominated flame retardant (BFRs). Exposure to BDE-209 has been clearly associated with male reproductive disorders. However, the meiotic arrest mechanism of spermatocytes exposed to BDE-209 is still unclear. The present work aimed to explore the protective effect of vitamin C on BDE-209-induced meiotic arrest of spermatocytes and its possible mechanism. Vitamin C (100 mg/kg BW) was administered to BDE-209-exposed (80 mg/kg BW) male Balb/c mice once daily by intraperitoneal injection for 2 weeks. Our results showed that vitamin C played male reproductive protection effects as showed by attenuated BDE-209-induced testicular damage, and reduced sperm abnormality rate. Vitamin C also attenuated BDE-209-induced increase in SOD and MDA in testes and GC-2 spd cells. Moreover, vitamin C promoted meiotic prophase in BDE-209-induced mice, with suppressed γ-H2AX, restored DMC1, RAD51, and crossover marker MLH1 levels, and prevented BDE-209-induced DNA impairment. In addition, vitamin C supplementation also interfered with BDE-209-induced upregulation of testicular H3K4me3 through inhibition of KDM5s capacity and decreasing ferrous ion concentration. Furthermore, ferrous sulfate pretreatment could partially restore the expression of H3K4me3 via maintaining the concentration of ferrous ions. Taken together, vitamin C exerts a potential therapeutic agent for preventing BDE-209-induced reproductive toxicity with meiotic arrest, which is attributed to its antioxidant and electron donor properties, as well as, modulation of ferrous ion levels and demethylation of H3K4me3.

Silymarin modulates cadmium-induced oxidative stress in human spermatozoa

Environmental pollutants such as cadmium can negatively affect sperm parameters and decrease male fertility by inducing oxidative stress. Antioxidants are considered a useful strategy for oxidative stress conditions to neutralize free radicals and strengthen the antioxidant defence system. In this study, the effects of the common application of silymarin, as a natural antioxidant, with cadmium were assessed on human sperm. The washed human sperm samples were divided into five groups: (1) spermatozoa at 0- hour; (2) spermatozoa at 3 h; (3) spermatozoa treated with cadmium (20 μM) for 3 h; (4) spermatozoa treated with silymarin (2 μM) + cadmium (20 μM) for 3 h and (5) spermatozoa treated with silymarin (2 μM) for 3 h. Our results displayed that cadmium reduced sperm motility, viability, plasma membrane integrity and acrosome integrity by increasing malondialdehyde levels and decreasing the total antioxidant capacity and antioxidant enzymes activity. While silymarin attenuated oxidative stress biomarkers in human sperm treated with cadmium, and consequently improved the sperm quality. In summary, cadmium-induced oxidative stress impaired human sperm structures and silymarin with its antioxidant properties compensated for the adverse effects of oxidative stress on human spermatozoa.

Atorvastatin ascorbic acid cocrystal strategy to improve the safety and efficacy of atorvastatin

The study was aimed to investigate the effect of dissolution enhancement on the hypolipidemic effect and hepatotoxicity of the drug in hyperlipidemic rats. Atorvastatin ascorbic acid cocrystals were prepared by phase solution methods and characterized by Fourier transformation infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, X-Ray powder diffraction. Results of characterization confirmed that atorvastatin ascorbic acid cocrystals exhibited particle size was 221 nm. In in vitro study, results of dissolution test showed that the release of atorvastatin was increased to 1.6 folds. From In vivo study results, it was observed that in atorvastatin ascorbic acid cocrystals treated rats, serum total cholesterol, triglycerides, liver transaminase levels were significantly decreased, and liver glutathione activity was increased. In conclusion, atorvastatin ascorbic acid cocrystals therapy exhibited less hepatotoxicity in presence of ascorbic acid when compared to atorvastatin alone therapy and also the efficacy of therapy was improved.

Vitamin C and E supplementation can ameliorate NaF mediated testicular and spermatozoal DNA damages in adult Wistar rats

OBJECTIVE

Present study was designed to explore the efficacy of vitamin C and E (VC&VE) against fluoride mediated testicular, epididymal and spermatozoal anomalies.

MATERIALS AND METHODS

Thirty two adult Wistar rats were divided into four groups. Group-I was control; Group-II received sodium fluoride (NaF) at 15 mg/kg/day dose; Group-III was provided with VC (200 mg/kg/day) and VE (400 mg/kg/day) plus NaF; Group-IV received only VC&VE. Structural integrity and oxidative stress markers (superoxide dismutase, catalase, malondialdehyde and protein carbonyl) of testis and epididymis were assessed. Spermatozoal parameters (count, motility, viability and hypo-osmotic swelling) were evaluated. Testicular functional maker enzymes (acid phosphatase, alkaline phosphatase and lactate dehydrogenase) were also assessed. Integrity of testicular and spermatozoal DNA were evaluated. Testicular fluoride content was measured.

RESULT

Fluoride induced structural changes and alterations of oxidative stress markers were observed in testis and epididymis. Spermatozoal potentials were altered and reduced activities of testicular functional marker enzymes were observed. Fluoride caused testicular and spermatozoal DNA damages. VC&VE supplementation resulted in protectionfrom all fluoride mediated alterations and helped in attenuating testicular fluoride accumulation.

CONCLUSION

Antioxidant properties of VC&VE ameliorated fluoride mediated reproductive damages but only supplementation did not exhibit any notable effect compared to control rats.

Effect of Environmental Stressors, Xenobiotics, and Oxidative Stress on Male Reproductive and Sexual Health

This article examines the environmental factor-induced oxidative stress (OS) and their effects on male reproductive and sexual health. There are several factors that induce OS, i.e. radition, metal contamination, xenobiotic compounds, and cigarette smoke and lead to cause toxicity in the cells through metabolic or bioenergetic processes. These environmental factors may produce free radicals and enhance the reactive oxygen species (ROS). Free radicals are molecules that include oxygen and disbalance the amount of electrons that can create major chemical chains in the body and cause oxidation. Oxidative damage to cells may impair male fertility and lead to abnormal embryonic development. Moreover, it does not only cause a vast number of health issues such as ageing, cancer, atherosclerosis, insulin resistance, diabetes mellitus, cardiovascular diseases, ischemia-reperfusion injury, and neurodegenerative disorders but also decreases the motility of spermatozoa while increasing sperm DNA damage, impairing sperm mitochondrial membrane lipids and protein kinases. This chapter mainly focuses on the environmental stressors with further discussion on the mechanisms causing congenital impairments due to poor sexual health and transmitting altered signal transduction pathways in male gonadal tissues.

Comparative transcriptomic analysis reveals reproductive impairments caused by PCBs and OH-PCBs through the dysregulation of ER and AR signaling

Reports have highlighted the presence of PCBs and their metabolites, OH-PCBs, in human serum as well as their endocrine-disrupting effects on reproductive function through direct interactions with the androgen receptor (AR) and estrogen receptor (ER). However, the molecular mechanisms directly linking the actions of PCBs and OH-PCBs on the AR and ER to induce reproductive impairment remain poorly understood. In this study, we characterized the cellular response to PCBs and OH-PCBs acting on AR and ER transactivation at the transcriptome level coupled with bioinformatics analysis to identify the downstream pathways of androgen and estrogen signaling that leads to reproductive dysfunction. We first confirmed the agonistic and antagonistic effects of several PCBs and OH-PCBs on AR- and ER-mediated reporter gene activity using the androgen-responsive LNCaP and estrogen-responsive MCF-7 cell lines, respectively. Anti-estrogenic activity was not detected among the tested compounds; however, we found that in addition to anti-androgenic and estrogenic activity, PCB 28 and PCB 138 exhibited androgenic activity, while most of the tested OH-PCBs showed a synergistic effect on DHT-mediated transactivation of the AR. Bioinformatics analysis of transcriptome profiles from selected PCBs and OH-PCBs revealed various pathways that were dysregulated depending on their agonistic, antagonistic, or synergistic effects. The OH-PCBs with estrogenic activity affected pathways including vitamin metabolism and calcium transport. Other notable dysregulated pathways include cholesterol transport in response to androgenic PCBs, thyroid hormone metabolism in response to anti-androgenic PCBs, and antioxidant pathways in response to androgen-synergistic OH-PCBs. Our results demonstrate that PCBs and OH-PCBs directly alter specific pathways through androgen- or estrogen-mediated signaling, thereby providing additional insights into the mechanisms by which these compounds cause reproductive dysfunction.

Dietary β-glucan influences the expression of testicular aquaporins, antioxidative defence genes and sperm quality traits in endangered golden mahseer, Tor putitora (Hamilton, 1822)

The effect of dietary β-glucan on seminal plasma composition, sperm characteristics, expression of aquaporins, and antioxidative defence genes of golden mahseer was evaluated. For that, four experimental diets containing 0 (control), 0.5, 1, and 1.5% β-glucan were fed to male golden mahseer brooders for 130 days. Feeding of 0.5% β-glucan was found to improve sperm characteristics, viz. sperm count, motility, viability, and morphology with no effect on gonadosomatic index and seminal plasma energy resources. The marked down-regulation in the transcript abundance of testicular aqp3a noticed in 1.5% β-glucan fed brooders corresponds to their poor sperm quality. Further, the mRNA expression of genes encoding antioxidant enzymes, namely gst and sod1, was lowest in 0.5% β-glucan fed brooders. In contrast, control and higher β-glucan (1 and 1.5%) groups displayed relatively higher expression levels of testicular gst and sod1. On the other hand, the higher seminal plasma total antioxidant capacity observed in 0.5 and 1% β-glucan fed brooders indicated increased scavenging ability of reactive oxygen species. Overall, supplementation of 0.5% β-glucan improved sperm quality and antioxidative potential, but the higher inclusion (1.5%) negatively affected sperm characteristics. Collectively, dietary β-glucan (0.5%) can be a practical approach to developing quality broodstock of golden mahseer.

Physiological Roles of Red Carrot Methanolic Extract and Vitamin E to Abrogate Cadmium-Induced Oxidative Challenge and Apoptosis in Rat Testes: Involvement of the Bax/Bcl-2 Ratio

The precise analysis of the contents of the red carrot is still ambiguous and its role in the maintenance of male fertility needs to be further reconnoitered. Hence, this study targets the physiological impacts of either red carrot methanolic extract (RCME) or vitamin E (Vit. E), co-administrated with cadmium chloride (CdCl₂) on rat testes, specifically those concerned with apoptosis and oxidative challenge. Four groups of adult male rats (n = 12) are used; control, CdCl₂, CdCl₂ + Vit. E and CdCl₂ + RCME. LC-MS analysis of RCME reveals the presence of 20 different phytochemical compounds. Our data clarify the deleterious effects of CdCl₂ on testicular weights, semen quality, serum hormonal profile, oxidative markers and Bax/Bcl-2 ratio. Histopathological changes in testicular, prostatic and semen vesicle glandular tissues are also observed. Interestingly, our data clearly demonstrate that co-administration of either RCME or Vit. E with CdCl₂ significantly succeeded in the modulation (p < 0.05) of all of these negative effects. The most striking is that they were potent enough to modulate the Bax/Bcl-2 ratio as well as having the ability to correct the impaired semen picture, oxidant status and hormonal profile. Thus, RCME and Vit. E could be used as effective prophylactic treatments to protect the male reproductive physiology against CdCl₂ insult.

Therapeutic effects of chitosan-embedded vitamin C, E nanoparticles against cisplatin-induced gametogenic and androgenic toxicity in adult male rats

Cisplatin, an anticancer drug used in treating various types of cancers, can cause reproductive toxicities during chemotherapy. Keeping this in view, the present study was designed to investigate the possible protective effects of normal vitamin C and E and vitamin C and E nanoparticles (embedded in chitosan) against cisplatin-induced reproductive toxicities. Vitamins C, E, and their nanoparticles in this regard proved to be an effective therapy. The work aimed to treat cisplatin-induced reproductive toxicities through vitamin C and E and their nanoparticles. Cisplatin exposure caused significant reduction in the weight, testosterone level, and changed lipid profile. Similarly, cisplatin induced significant widespread testicular atrophy and testicular lesions as evidenced by the gaps in the epithelium and loss of differentiating germ cells. Vitamin C and E and their nanoparticles rescued the weight, testosterone level, and testicular disturbances, which is associated with improved histological view of testicular tissues. The current study highlights evidence that designing a medication of vitamin C and E nanoparticles is useful in mitigating cisplatin-induced reproductive toxicity in cancerous male patients underlying chemotherapy.

Cnidoscolus aconitifolius leaf extract and ascorbate confer amelioration and protection against dimethyl nitrosamine-induced renal toxicity and testicular abnormalities in rats

Extracts of Cnidoscolus aconitifolius (CA) have been reported to possess medicinal properties ranging from potential hepatoprotective, anti-diabetic, and anti-cardiovascular. In our previous study, gas chromatography mass spectroscopy check of CA extract showed the inclusion of 2,4-bis(1,1-dimethylethyl)-phenol, a phenolic phyto-compound that constitutes about 45 %, carotene and linoleic acid sources, and silicon-rich components. Hence we compare the preventive and ameliorative potentials of CA with ascorbate in dimethyl nitrosamine (DMN)-induced renal toxicity and sperm abnormalities in rats. Renal toxicity was investigated by quantifying the levels and activities of endogenous antioxidant parameters. Renal damage marked by significant reduction in GSH level, as well as significant elevation in MDA concentration, and activities of GPx, GST, CAT, and SOD were restored after the intervention of CA and ascorbate. Also, there was decrease in live sperm, sperm concentration, sperm gross and individual motility, and normal sperm morphology, following DMN administration. Based on the gathered results, it is concluded that ascorbate and CA demonstrate comparable ameliorative and protective effects against DMN-induced renal and testicular toxicities in rats.

Protective Effect of Combined Long Time Administration of Selenium and Vitamin C on Liver and Kidney Toxicity of Cadmium in Rats

Background & Objective:

Increased industrial activities leads to prolonged human exposure to industrial pollutant such as cadmium (Cd). ‍Chronic exposure to Cd in Mammals and also human being, can cause damages to various organs and particularly kidneys and liver. The goal of this study was to investigate the prophylactic effects of combined selenium (Se) and ascorbic acid supplement in rat cadmium toxicity.

Methods:

Sixty adult male Wistar rats were divided to 10 groups: one control, one sham and two clusters of 4 intervention groups which were fed with 1 or 5 mg Cd /kg water, for 28 days. Ascorbic acid supplement was added to drinking water of four groups (10 mg/L). Four groups received intraperitoneal Se (1 mg/kg) at day 1, 5, 10, 15, 20 and 25. Finally, Cd concentration was measured by atomic absorption spectrophotometry in liver and kidney sections. Furthermore, pathological changes were investigated in these sections.

Results:

The results showed weight gain in Cd groups which received ascorbic acid and Se, in contrast to weight loss in parallel groups without vitamin C and Se. The stronger necrosis and inflammation have been observed in group received 5 mg/kg Cd compared to group with 1 mg/kg Cd (P<0.05). In addition, cadmium level was higher in untreated groups without any supplements, significantly (P<0.05).

Conclusion:

Drinking water with ascorbic acid may have prophylactic effects across cadmium, and combination of Se and ascorbic acid are associated with higher prophylactic effects in both kidney and liver in rats to decrease the Cd toxicity.

Momordica charantia Extract Protects against Diabetes-Related Spermatogenic Dysfunction in Male Rats: Molecular and Biochemical Study

More than 90% of diabetic patients suffer from sexual dysfunction, including diminished sperm count, sperm motility, and sperm viability, and low testosterone levels. The effects of Momordica charantia (MC) were studied by estimating the blood levels of insulin, glucose, glycosylated hemoglobin (HbA1c), testosterone (TST), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in diabetic rats treated with 250 and 500 mg/kg b.w. of the total extract. Testicular antioxidants, epididymal sperm characteristics, testicular histopathology, and lesion scoring were also investigated. Testicular mRNA expression of apoptosis-related markers such as antiapoptotic B-cell lymphoma-2 (Bcl-2) and proapoptotic Bcl-2-associated X protein (Bax) were evaluated by real-time PCR. Furthermore, caspase-3 protein expression was evaluated by immunohistochemistry. MC administration resulted in a significant reduction in blood glucose and HbA1c and marked elevation of serum levels of insulin, TST, and gonadotropins in diabetic rats. It induced a significant recovery of testicular antioxidant enzymes, improved histopathological changes of the testes, and decreased spermatogenic and Sertoli cell apoptosis. MC effectively inhibited testicular apoptosis, as evidenced by upregulation of Bcl-2 and downregulation of Bax and caspase-3. Moreover, reduction in apoptotic potential in MC-treated groups was confirmed by reduction in the Bax/Bcl-2 mRNA expression ratio.

Nanocurcumin versus mesenchymal stem cells in ameliorating the deleterious effects in the cadmium-induced testicular injury: A crosstalk between oxidative and apoptotic markers

Cadmium (Cd), a grave occupational pollutant, can result in; testicular damage. This study was designed to distinguish the potential effect of bone marrow-derived mesenchymal stem cells (BM-MSCs) versus that of curcumin nanoemulsion on Cd-induced testicular damage. Fifty adult male Sprague Dawley rats were distributed into five groups; control, sham control, Cd-treated, stem cell-treated and nanocurcumin-treated groups. Histological, immune histochemical; caspase 3 and proliferating cell nuclear antigen (PCNA) and CD 68, testosterone levels, nitric oxide, malondialdehyde (MDA)/glutathione (GSH) superoxide, dismutase (SOD), Western blot; B-cell lymphoma (Bcl-2), BCL2-Associated X Protein (BAX), BAX/Bcl-2 ratio and morphometry were done. Cadmium-treated group showed degenerated, detached seminiferous tubules, vacuolations and wide interstitial spaces containing fluid exudates. The same group revealed increased expression of BAX, BAX/Bcl-2 ratio, caspase 3, CD 68 and increased mean values of MDA, NO. Concomitantly, Cd has significant reduction in PCNA, Bcl-2 and sperm cell count when compared to control group. BM-MSCs- and nanocurcumin-treated groups revealed well-structured tubules and were perceived to expressively enhance the deleterious changes induced by Cd. The injurious changes on the testis induced by Cd were obviously improved when treated with either MSCs or nano-curcumin. BM-MSCs exerted more ameliorative changes.

Effects of Myo-inositol Alone and in Combination with Seleno-Lmethionine on Cadmium-Induced Testicular Damage in Mice

BACKGROUND

Cadmium (Cd) impairs gametogenesis and damages the blood-testis barrier.

OBJECTIVE

As the primary mechanism of Cd-induced damage is oxidative stress, the effects of two natural antioxidants, myo-inositol (MI) and seleno-L-methionine (Se), were evaluated in mice testes.

METHODS

Eighty-four male C57 BL/6J mice were divided into twelve groups: 0.9% NaCl (vehicle; 1 ml/kg/day i.p.); Se (0.2 mg/kg/day per os); Se (0.4 mg/kg/day per os); MI (360 mg/kg/day per os); MI plus Se (0.2 mg/kg/day); MI plus Se (0.4 mg/kg/day); CdCl2 (2 mg/kg/day i.p.) plus vehicle; CdCl2 plus MI; CdCl2 plus Se (0.2 mg/kg/day); CdCl2 plus Se (0.4 mg/kg/day); CdCl2 plus MI plus Se (0.2 mg/kg/day); and CdCl2 plus MI plus Se (0.4 mg/kg/day). After 14 days, testes were processed for biochemical, structural and immunohistochemical analyses.

RESULTS

CdCl2 increased iNOS and TNF-α expression and Malondialdehyde (MDA) levels, lowered glutathione (GSH) and testosterone, induced testicular lesions, and almost eliminated claudin-11 immunoreactivity. Se administration at 0.2 or 0.4 mg/kg significantly reduced iNOS and TNF-α expression, maintained GSH, MDA and testosterone levels, structural changes and low claudin-11 immunoreactivity. MI alone or associated with Se at 0.2 or 0.4 mg/kg significantly reduced iNOS and TNF-α expression and MDA levels, increased GSH and testosterone levels, ameliorated structural organization and increased claudin-11 patches number.

CONCLUSION

We demonstrated a protective effect of MI, a minor role of Se and an evident positive role of the association between MI and Se on Cd-induced damages of the testis. MI alone or associated with Se might protect testes in subjects exposed to toxicants, at least to those with behavior similar to Cd.

Ameliorative effect of edible Halopteris scoparia against cadmium-induced reproductive toxicity in male mice: A biochemical and histopathologic study

Cadmium (Cd) is a toxic metal affecting the reproductive system. Halopteris scoparia (brown algae) is generally consumed as a salad in the Far East countries. This study was conducted to compare and determine the possible protective effects of H. scoparia and vitamin E and C combination (VEC) against cadmium chloride (CdCl2 )-induced reproductive toxicity. A total of 36 male mice were equally divided into as control, CdCl2 (2 mg/kg), CdCl2  + H. scoparia (900 mg/kg), CdCl2  + VEC (200 mg/kg), H. scoparia alone and VEC alone groups. Blood and testis samples were taken for biochemical, histochemical and immunohistochemical analyses. H. scoparia was also examined for antioxidant activity (by DPPH assay) and mineral/trace element content (by ICP-MS method). CdCl2 exposure caused a significant deterioration in body weight, sperm parameters (count, motility, viability and morphology) (p < .001), histopathology, immunoreactivity and testosterone levels. However, H. scoparia improved CdCl2 -induced deterioration effects more successfully than VEC-treated group. The present study suggests that edible H. scoparia can be used as a natural protective agent against Cd-induced testicular damage by possibly enhancing essential element levels or increasing antioxidant defence system.

Low-dose heavy metal mixture (lead, cadmium and mercury)-induced testicular injury and protective effect of zinc and Costus afer in wistar albino rats

The study evaluated the protective effect of Costus afer on low-dose heavy metal mixture (LDHMM)-mediated effects in the testis of albino rats. The weight-matched animals were divided into six groups: normal control, metal mixture of (PbCl₂  + CdCl₂ + HgCl₂ ), combination of metal mixture + Costus afer at 750 mg/kg, combination of metal mixture + Costus afer at 1,500 mg/kg, combination of metal mixture + Costus afer at 2,250 mg/kg and combination of metal mixture + (ZnCl₂ ). LDHMM reduced (p < .05) the antioxidant biomarkers (superoxide dismutase, SOD; catalase, CAT; and glutathione, GSH) and increased (p < .05) the lipid peroxidation marker (malondialdehyde, MDA) and lead, cadmium and mercury concentrations in the testis. Treatment with LDHMM increased (p < .05) abnormal sperm morphology and plasma prolactin (PRL) level and decreased epididymal sperm count, viability, follicle-stimulating hormone (FSH), luteinising hormone (LH) and testosterone. LDHMM exposure caused deleterious changes in the testis. Treatment of rats with Costus afer (750, 1,500 and 2,250 mg/kg) dose-dependently reduced (p < .05) the LDHMM-mediated toxicity. Treatment with Costus afer also reversed the testicular weight and LDHMM decrease in antioxidant biomarkers. Costus afer may be a defensive modulator of LDHMM-mediated testicular lesions.

Toxicological Effects of Cadmium on Mammalian Testis

Cadmium is a heavy metal, and people are exposed to it through contaminated foods and smoking. In humans and other mammals, cadmium causes damage to male testis. In this review, we summarize the effects of cadmium on the development and function of the testis. Cadmium causes severe structural damage to the seminiferous tubules, Sertoli cells, and blood-testis barrier, thus leading to the loss of sperm. Cadmium hinders Leydig cell development, inhibits Leydig cell function, and induces Leydig cell tumors. Cadmium also disrupts the vascular system of the testis. Cadmium is a reactive oxygen species inducer and possibly induces DNA damage, thus epigenetically regulating somatic cell and germ cell function, leading to male subfertility/infertility.

Protective effects of vitamin E on aluminium sulphate-induced testicular damage

Male infertility can be caused by environmental factors, genetic defects, physiological and endocrine deficiencies and testicular pathologies. Aluminium (Al) can cause male infertility through a number of mechanisms. The aim of our study was thus to determine whether vitamin E (VitE) has protective effects on Al-induced testicular damage, which was determined according to sperm counts and morphology and using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method. Thirty-four male Wistar rats (250-300 g) were randomly assigned to control (no procedures performed; n = 6) or 0.2 mL intraperitoneal injection group (n = 7 each; three times per week for 4 weeks): sham (distilled water), 10 mg/kg Al, 500 mg/kg VitE and 10 mg/kg Al plus 500 mg/kg VitE (Al + VitE). Sperm samples were evaluated for andrological parameters. The testes were examined by haematoxylin/eosin. The epithelial thickness and areas were calculated and Johnsen scores were determined for the germinal epithelium; the apoptotic indices were determined from TUNEL staining. For Al, the bonds between the germinal epithelial cells were broken in some tubules, and there were unidentified cells in the lumen of some tubules. For control, sham and VitE, normal morphology of the germinal epithelium was generally preserved. With Al + VitE, the full germinal epithelium cell series was maintained, with only mature sperm in the lumen. TUNEL-positive cells were significantly higher with Al compared to control and sham (p < 0.05). For Al + VitE, the number of apoptotic cells was reduced compared to Al alone and was therefore similar to control, sham and VitE (p > 0.05). Our findings show that Al caused testicular damage. VitE reduced the number of apoptotic cells during the damage caused by Al.

Oxidative stress in the pathophysiology of male infertility

The effects of reactive oxygen species on male fertility are governed by the oxidative paradox, defined by a delicate balance between oxidative stress and antioxidant capacity. When regulated appropriately, reactive oxygen species ensure effective function; however, when uninhibited, they represent key players in male factor infertility. Mechanisms responsible for this include oxidative destruction of sperm lipid membranes, damage to gamete DNA both by gene mutation and by direct breakdown of the DNA backbone, mitochondrial dysfunction and apoptotic cell death. Utilizing various male pathologies as case studies, we see ways in which oxidative stress has the potential to impact fertility in a negative way. Varicocele, erectile dysfunction, testicular cancer and even idiopathic male infertility highlight common mechanistic pathways, as well as subtle variations in the ways reactive oxygen species can operate. Oxidative biomarkers have emerged to better study male infertility, predict reproductive success and modify assisted reproductive technologies to minimize oxidative stress.

Cadmium-Induced Testicular Toxicity in Mice: Subacute and Subchronic Route-Dependent Effects

This study aimed to compare Cd exposure by intraperitoneal (i.p.) and oral routes, evaluating the testicular subacute and subchronic effects. Adult male mice were separated into three groups subdivided according to the experimental period (7 and 42 days after Cd exposure: subacute and subchronic effects, respectively): one group received water and two groups received CdCl₂ (1.2 mg/kg i.p. and 24 mg/kg oral). The testicular concentration of essential minerals and Cd, activity of antioxidant enzymes and markers of oxidative stress, histology, and testicular histomorphometry were evaluated. The subacute effect of oral Cd showed reduced Fe concentration, while Ca and Cu increased in this route. The subchronic effect promoted decreasing in Mg in i.p. and oral routes, whereas Zn decreased only in the oral, and the Fe concentration did not change. SOD activity decreased in the oral subacute evaluation and in both pathways, i.p. and oral routes, in the subchronic evaluation, while GST activity increased, and MDA concentration decreased. Labeling of apoptotic cells was increased in the subacute and subchronic evaluation. Seminiferous epithelium degeneration, death of germ cells, and Leydig cell damages occurred in i.p. and oral routes. However, these damages were more intense in the oral route, mainly evaluating the subchronic effects. The results confirm that the severity of Cd-induced testicular injury depends on the pathway, as well as the duration of exposure.

Curcumin protects the testis against cadmium-induced histopathological damages and oxidative stress in mice

BACKGROUND

Cadmium is an environmental pollutant which can induce the overproduction of free radicals while suppressing the antioxidant defense system. Curcumin is considered a free-radical scavenger and a potent antioxidant. This study was conducted to investigate the effect of curcumin on serum antioxidant enzymes and histopathological changes in mice treated with cadmium.

METHODS

In this experimental study, adult mice were divided into four groups, namely, control, cadmium chloride (5 mg kg^-1), curcumin (100 mg kg^-1), and curcumin+cadmium chloride. The animals received curcumin 24 h prior to cadmium chloride injection. After 24 h, blood samples were collected and used to assess the levels of malondialdehyde (MDA), antioxidant enzymes activity (catalase, superoxide dismutase, and glutathione peroxidase), total glutathione, total thiol, and hydrogen peroxide. Histopathological evaluation was also performed for testicular tissue.

RESULTS

Mice treated with cadmium showed a significant (p < 0.001) decrease in the activity of antioxidant enzymes, serum amounts of total glutathione and total thiol, and the diameter of seminiferous tubules compared to the control group. This pollutant also significantly (p < 0.001) increased serum levels of MDA and hydrogen peroxide and the lumen diameter of seminiferous tubules compared to the control group. In the curcumin+cadmium group, curcumin significantly (p < 0.001) reversed the adverse effects of cadmium, compared to the cadmium group. In addition, curcumin alone significantly (p < 0.001) increased serum glutathione peroxidase activity and thiol content compared to the control group.

CONCLUSION

Curcumin, as a potent antioxidant, could compensate the adverse effects of cadmium on lipid and protein peroxidation, potentiated serum antioxidant defense system, and ameliorated some morphometrical parameters in the testis of cadmium-treated mice.

Increasing ERK phosphorylation by inhibition of p38 activity protects against cadmium-induced apoptotic cell death through ERK/Drp1/p38 signaling axis in spermatocyte-derived GC-2spd cells

Many studies report that cadmium chloride (CdCl₂)-induces oxidative stress is associated with male reproductive damage in the testes. CdCl₂ also induces mitochondrial fission by increasing dynamin-related protein 1 (Drp1) expression as well as the mitochondria-dependent apoptosis pathway by extracellular signal-regulated kinase (ERK) activation. However, it remains unclear whether mechanisms linked to the mitochondrial damage signal via CdCl₂-induced mitogen-activated protein kinases (MAPK) cause damage to spermatocytes. In this study, increased intracellular and mitochondrial reactive oxygen species (ROS) levels, mitochondrial membrane potential (∆Ψm) depolarization, and mitochondrial fragmentation and swelling were observed at 5 μM of CdCl₂ exposure, resulting in increased apoptotic cell death. Moreover, CdCl₂-induced cell death is closely associated with the ERK/Drp1/p38 signaling axis. Interestingly, SB203580, a p38 inhibitor, effectively prevented CdCl₂-induced apoptotic cell death by reducing ∆Ψm depolarization and intracellular and mitochondrial ROS levels. Knockdown of Drp1 expression diminished CdCl₂-induced mitochondrial deformation and ROS generation and protected GC-2spd cells from apoptotic cell death. In addition, electron microscopy showed that p38 inhibition reduced CdCl2-induced mitochondrial interior damage more effectively than N-acetyl-L-cysteine (NAC), an ROS scavenger; ERK inhibition; or Drp1 knockdown. Therefore, these results demonstrate that inhibition of p38 activity prevents CdCl₂-induced apoptotic GC-2spd cell death by reducing depolarization of mitochondrial membrane potential and mitochondrial ROS levels via ERK phosphorylation in a signal pathway different from the CdCl₂-induced ERK/Drp1/p38 axis and suggest a therapeutic strategy for CdCl₂-induced male infertility.

Subacute Testicular Toxicity to Cadmium Exposure Intraperitoneally and Orally

The toxic effects of cadmium (Cd) on reproductive parameters are widely described in the literature. Experimental models often make use of the intraperitoneal route (i.p.), although human intoxication occurs preferentially by the oral route and can be continuous. However, little is known about the effect of Cd administration routes on the testicular structure. Thus, this study investigated the testicular impact of Cd exposure comparing both i.p. and oral routes, both single dose (SD), in addition to the oral route in fractional doses (FD). Swiss adult male mice received CdCl₂ 1.5 mg/kg i.p., 30 mg/kg oral SD, and 4.28 mg/kg oral FD for 7 consecutive days. The Cd bioaccumulation was observed in all routes, mainly in the oral FD route. The concentrations of testicular Ca and Cu decreased in all animals exposed to Cd, while Zn and Mn decreased only in the i.p. route. Testicular SOD activity was reduced in both routes of oral administration, while CAT increased in the i.p. route, and GST increased in all animals exposed to Cd. Changes in the tubular parameters and cell viability were observed in both routes of Cd administration but were more intense in the oral route, mainly in the FD. Serum testosterone concentration was reduced in both routes of oral administration. Tubular damage, such as the vacuolization of the seminiferous epithelium, germ cell detachment, and seminiferous tubule degeneration, occurred in all groups exposed to Cd. Therefore, the oral Cd administration presented greater potential to promote testicular damage, mainly when the metal was given in a fractionated way.

Effects of Cadmium and /or Chromium on reproductive organs and semen profiles of male albino rats

Objective: To evaluate the potential hazards of cadmium and/or chromium on the reproductive system of adult male albino rat. Design: Randomized controlled study. Animals: Forty mature male albino rats weighing 260 ± 10 g. Procedures: Rats were allocated into four groups (ten animals each). Control group (group 1), group 2 received 4.4 mg kg-1 cadmium chloride, group 3 was given 2.5 mg kg-1 sodium dichromate and group 4 received combination of Cd (2.2 mg kg-1) and Cr (1.25mg kg-1) orally, once daily for 65 consecutive days. Results: Exposure to Cd or Cr, in particular their combination, caused a reduction in the index weights of testes, epididymis, seminal vesicle and prostate glands. They induced a reduction of sperm count and viability with an increase of abnormal sperm morphology. Interestingly, in the combination group (Cd and Cr together), the deleterious effects were more noticeable. Pathologically, both Cd and Cr produced degenerative changes in seminiferous tubules, necrosis of spermatogenic epithelium within the testis. Moreover, the interstitial tissue of epididymis showed marked edema and prostate showed necrosis and serous exudate of lining epithelium. In the interaction group, testis showed complete degenerative changes and necrosis of spermatogenic epithelium, with marked interstitial edema and hyperplastic epithelial lining of epididymal tubules. Conclusion and clinical relevance: The present results support the hypothesis that the testis is one of the most sensitive organs to Cd and/or Cr and that the exposure to any of them or to their combination lead to testicular damage and thereby male infertility.

Preventative Effects of Vitamin E on Testicular Damage and Sperm Parameters in the First-Generation Mice Pups due to Pre- and Postnatal Mancozeb Exposure

The present study aimed to evaluate the effects of vitamin E on mancozeb-induced testis damage of the first-generation pups during intrauterine and lactating periods. Two groups of pregnant NMRI mice received 500 mg/kg mancozeb (MNZ) as MNZ group and 200 mg/kg vitamin E as MNZ+vit.E group before receiving MNZ. In addition, a vehicle and a control group were designed every other day in gestation and lactation periods. The male pups from each group were maintained until adulthood (8-10 W). The left testes and epididymides were removed following the sacrifice of the pups. Then, they were weighed, and sperm parameters including number, viability, motility, and morphology and testis structure were evaluated. A significant decrease occurred in sperm parameters of the mancozeb-treated pups compared to the control and vehicle groups. Treatment with vitamin E reversed the deleterious effects of MNZ to a nearly normal condition. Testis parameters including the weight, gonadosomatic index, seminiferous tubule diameters, and Johnsen's score, as well as the number of germ cells such as spermatogonia, spermatocyte, spermatid, and Sertoli, decreased significantly in the MNZ group, compared to the amount in the control and vehicle groups. Interestingly, the treatment with vitamin E was reversed in most of these parameters. Based on the results, the exposure of pups to mancozeb during pregnancy and lactating periods negatively affects the reproductive system of male pups. However, the coadministration of vitamin E could prevent the deleterious effects of mancozeb on sperm and testis parameters.

Reproductive toxicity of acute Cd exposure in mouse: Resulting in oocyte defects and decreased female fertility

Cadmium (Cd), a known metal contaminant, is widespreadly used in industry, thereby human health is severely affected through the way of occupational and environmental exposure. The adverse effects of the exposure to Cd on the female reproductive system, especially oocyte maturation and fertility have not been clearly defined. In this study, we found the arrested development of ovaries and uteri after Cd exposure and determined oocyte quality via assessing the key regulators during meiotic maturation and fertilization. We found that Cd exposure impeded the mouse oocyte meiotic progression by disrupting the normal spindle assembly, chromosome alignment and actin cap formation. Besides, exposure to Cd induced oxidative stress with the increased reactive oxygen species and apoptosis levels, leading to abnormal mitochondrial distribution, insufficient energy supply, and DNA damage, which ultimately led to oocyte quality deterioration. We also analyzed the effects of cadmium on epigenetic modifications, and the levels of 5mC, H3K9me3 and H3K9ac decreased after acute exposure to cadmium. Further experiments showed that the litter size in Cd-exposed female mice reduced, thereby indicating increased reproductive Cd toxicity. In conclusion, Cd exposure impairs oocyte maturation and fertilization ability induced by oxidative stress, early apoptosis and epigenetic modifications, which lead to the decrease of female fertility.

The protective role of ascorbic acid in the hepatotoxicity of cadmium and mercury in rabbits

The liver is one of the vital and sensitive organs which are usually exposed against the toxicity of mercury (Hg) and cadmium (Cd). The main objective of the current study was to evaluate the potential toxicological effects of both Cd and Hg as individual and combined. Hepatotoxicity was evaluated by monitoring the biochemical parameters of the liver and their accumulation in the liver as well as therapeutic role of vitamin C in said toxicity in rabbits (Oryctolagus cuniculus). In this research, cadmium chloride (1.5 mg/kg), mercuric chloride (1.2 mg/kg), and vitamin C (150 mg/kg of body weight) were orally administered to treatment groups of the rabbits for 28 alternative days. Various biochemical parameters of the liver such as lactate dehydrogenase (LDH), aspartate aminotransferase (ASAT), bilirubin, alanine aminotransferase (ALAT), total protein, and gamma glutamyl transferase (GGT) were estimated using blood samples. Some biochemical parameters like ASAT, ALAT, LDH, GGT, and bilirubin were significantly elevated (P ≤ 0.001) in individual Cd and Hg treatment groups, while the level of total protein was found to be significantly declined. The effects of Cd and Hg in the presence of vitamin C on these biochemical parameters were low as compared to metals-treated groups. Similar results were found when rabbits were treated with co-administration of both metals and vitamin C. Accumulation of Cd and Hg found to be higher in the liver. However, chemoprevention and chemotreatment with vitamin C significantly (P ≤ 0.01) minimized the toxicological effects of both metals but not regained the accumulation similar to that of the control group. The findings of this study provide awareness on accumulation of metals in the liver in rabbits and their toxicity tested through biochemical parameters as well as the therapeutic role of vitamin C in such alterations.

Cadmium level in brain correlates with memory impairment in F1 and F2 generation mice: improvement with quercetin

The increased exposure to cadmium (Cd) through environmental pollutants, food and cigarette smoke is a concern worldwide. The association of Cd with impaired learning disabilities led us to hypothesise that cadmium levels in brain tissue could be dose-dependently related to the extent of memory impairment and oxidative stress. In this study, we proposed to study whether cadmium exposure to dams could alter the brain Cd levels, memory parameters, antioxidant enzymes in brain and their gene expression in the F1-F2 generation mice and whether quercetin could modulate this effect. Animals were administered Cd alone and in combination with quercetin for 7 days during their gestation period. Their newborn pups (F1 and F2 mice) were reared until adulthood and were tested for memory using Morris water maze and step-down latency test. The brain tissue of F1 mice was collected. Cd levels were estimated using the atomic absorption spectrophotometer. G-S-transferase (GST) and catalase (CAT) activity were measured and fold increase in their respective gene expression was observed using the RT-PCR method. Cd levels were significantly increased in the brain tissue of animals exposed to Cd but cotreatment with quercetin showed decreased levels in both generations. Memory impairment was observed in animals of F1 generation exposed to Cd and cotreatment with quercetin (100 mg/kg) reversed this effect. Cd exposure significantly enhanced both activity and expression of GST and CAT in the brain tissue of F1 generation mice and quercetin attenuated this effect. In F2 generation, results were variable. GST activity and expression increased with Cd and decreased with quercetin cotreatment. However, CAT activity showed no significant change despite a decrease in gene expression. Quercetin cotreatment enhanced activity as well gene expression in F2 generation. Our study insinuates that Cd levels could act as a predictor of memory impairment and altered enzyme activity and gene expression in brain tissue. Quercetin helped to reduce Cd levels in brain tissue of F1 and F2 generation and modulated the antioxidant system of the cell by affecting expression of antioxidant enzymes at the transcription level.

Coenzyme Q10 ameliorates cadmium induced reproductive toxicity in male rats

This study aimed at investigating the protective role of CoQ10 against cadmium (Cd)-induced reproductive toxicity in male rats. Adult male Wistar rats were exposed to an acute dose of Cd (25 mg/kg bwt; Cd group), Cd+CoQ10 (25 mg/kg bwt Cd+10 mg CoQ10; Cd-Q10 group) and distilled water (control) in vivo for 15 consecutive days and semen quality was assessed. A significant reduction was noted in sperm concentration, progressive motility, morphology and DNA integrity in both Cd- and Cd-Q10 groups in comparison to control indicating Cd-induced testicular lipid per oxidation (LPO) and decline in indigenous antioxidant defense system as measured by total antioxidant capacity (TAC) (p<0.05). However, simultaneous co-administration of CoQ10 along with Cd (Cd-Q10 group) was able to improve sperm concentration, motility, progressive motility, morphology, DNA integrity, and testicular TAC as well as lower LPO compared to Cd group (p<0.05). Results indicate that used dose of CoQ10 is capable of moderately ameliorating reproductive toxicity of Cd by improving semen quality and reducing testicular oxidative stress.

Alteration in cognitive behaviour, brain antioxidant enzyme activity and their gene expression in F1 generation mice, following Cd exposure during the late gestation period: modulation by quercetin

We investigated whether in-utero Cd(II) chloride exposure of the dams between 14th to 21st day of gestation affects memory and learning, oxidative stress, antioxidant enzyme activity and their gene expression in brain of the pups in their adulthood. In the Morris water maze, cadmium (Cd) exposure impaired spatial memory which was reversed following co-treatment with quercetin (100 mg/kg). In the passive avoidance paradigm, retention memory was adversely affected but was significantly reversed by co treatment with quercetin (25, 50, 100 mg/kg). The malondialdehyde and catalase (CAT) levels and glutathione-S-transferase (GST) activity were increased significantly in Cd-treated group, but were reversed by quercetin (all doses). The gene expression for CAT and GST in brain tissue of Cd treated animals also increased many folds as compared to the control, and this effect was decreased on co-treatment with quercetin (all doses), thus matching with the respective enzyme activities. Quercetin (25 mg/kg) when co-treated with Cd caused a decrease in GST activity compared to control, which points towards a complex interplay with oxidative free radicals and promoters and transcription factors. Thus, Cd exposure during late gestation causes impaired spatial and retention memory in the next generation which may be due to alteration of activity as well as gene expression of the antioxidant enzymes, CAT and GST. Quercetin may offer some protection of memory impairment probably by modulating these effects.

Silymarin Ameliorates Oxidative Stress and Enhances Antioxidant Defense System Capacity in Cadmium-Treated Mice

OBJECTIVE

Cadmium is an environmental pollutant which induces oxidative stress while silymarin as an antioxidant is able to scavenge free radicals. The aim of the present study was to investigate the effect of silymarin on oxidative stress markers and antioxidant defense system capacity in mice treated with cadmium chloride.

MATERIALS AND METHODS

In this experimental study, adult mice were divided into four groups as follow: i. Control, ii. Cadmium chloride (5 mg/kg b.w., s.c.), iii. Silymarin+cadmium chloride, and iv. Silymarin (100 mg/kg b.w., i.p.). Mice were treated with cadmium chloride for 24 hours and silymarin was administered 24 hours before the cadmium. Blood samples were then collected from the experimental groups and their sera were prepared. To investigate oxidative stress markers in the serum, the amount of malondialdehyde (MDA) and thiol groups (-SH) were evaluated. To measure the total antioxidant power in the serum, Ferric Reducing/ Antioxidant Power (FRAP) method was used. In addition, the activity of enzymes including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) was assessed to evaluate serum antioxidant defense power.

RESULTS

In the cadmium-treated group, the amount of MDA significantly increased as compared to the control group. In silymarin+cadmium group, silymarin significantly ameliorated the level of MDA compared to the cadmium group. In addition, cadmium significantly reduced serum FRAP, the activity of antioxidant defense system enzymes and thiol groups compared to the control. In silymarin+cadmium group, silymarin could significantly reverse the reduction of these markers compared to the cadmium group. Administration of silymarin alone caused a significant increase in serum FRAP, the activity of antioxidant defense system enzymes and thiol groups compared to the control group.

CONCLUSION

Silymarin as a powerful antioxidant reverses the toxic effect of cadmium on the serum levels of lipid peroxidation, total antioxidant power, antioxidant defense system enzymes activity and thiol groups.

Oral administration of cadmium depletes intratesticular and epididymal iron levels and inhibits lipid peroxidation in the testis and epididymis of adult rats

Cadmium (Cd)-induced tissue injury depends on the accumulated Cd which differentially affects endogenous iron (Fe). To investigate this, adult rats were treated by oral gavage with Cd (50 mg/kg body wt.) once a week for 15, 30 and 60 days and sacrificed a day after last administration. After the 15th and 30th day of treatment, Cd had no effect on thiobarbituric acid reactive substances (TBARS) and endogenous Fe levels but exhibited anti-androgenic effects (p < 0.05) and caused histological damages. At day 60, Cd was accumulated by 156.30% and 364.77% above control values at concentrations that decreased endogenous Fe levels by 46.41% and 50.31% in the testis and epididymis respectively. The histological damages were characterized by decreased tubular diameter, damage to the epithelium leading to loss of tubular germ cells and absent of spermatozoa in the epididymal lumen. Although myeloperoxidase activities were increased, TBARS levels were found to decrease significantly at day 60 in the serum, testis and epididymis suggesting that the histological damages were not caused by lipid peroxidation. Furthermore, TBARS correlated negatively with Cd in the testis (r = -0.251, p < 0.05) and epididymis (r = -0.286, p < 0.05); Fe correlated positively with TBARS in the testis (r = +0.217, p < 0.05) and Cd correlated negatively with Fe in the testis (r = -0.461, p < 0.05) and epididymis (r = -0.109, p < 0.05). The antioxidant enzymes, superoxide dismutase and glutathione peroxidase were also decreased in the gonads after 60 days Cd treatment. Overall, anti-androgenic effects and histo-pathological changes are early indicators of direct effects of Cd and occur before decrease in TBARS which is secondarily related to the modifying of Fe contents.

Profertility effects of Shilajit on cadmium-induced infertility in male mice

Shilajit is claimed as a Vajikarak (aphrodisiac) and used for the treatment of male infertility by traditional healers of the Indian subcontinent. Therefore, the present investigation was designed to assess the effectiveness of Shilajit for treatment of male infertility resulting from exposure to perilous chemicals. Effect of daily oral administration (p.o.) of Shilajit (50 mg, 100 mg and 200 mg/Kg BW) was investigated for a single spermatogenic cycle (35 days) in cadmium-induced (2 mg/Kg BW, p.o. for 35 days) infertile adult (12-14 week) swiss male mice. Shilajit treatment increased weights of reproductive organs, testicular daily sperm production, activities of testicular Δ⁵ 3β-HSD and 17 β-HSD enzymes and serum level of testosterone. Histopathological evaluation of testis revealed that Shilajit restored spermatogenesis as reflected by a gradual augmentation in germ cell layers with increased doses of Shilajit compared to cadmium-treated mice. Further, Shilajit treatment reverted back the adverse effects of cadmium on motility and concentration of spermatozoa. Secretory activities of the epididymis and seminal vesicle and libido, fertility and the number of litters per female were also improved by Shilajit in cadmium-treated mice. Results thus suggest the potent androgenic nature of Shilajit and its role in fertility improvement against cadmium-induced infertility.