Effect of selenium on carbimazole-induced testicular damage and oxidative stress in albino rats

Impact of carbimazole combined with vitamin E on testicular injury induced by experimental hyperthyroidism in adult albino rats: oxidative/inflammatory/apoptotic pathways

Thyroid hormones play essential roles in spermatogenesis, but their effects on infertile males remain poorly understood. This study aimed to evaluate the impact of combining carbimazole (CBZ) with vitamin E (VE) on testicular injury induced by experimental hyperthyroidism in adult albino rats, focusing on oxidative, inflammatory, and apoptotic pathways. In this experimental study, 64 adult male albino Wistar rats were divided into eight groups: Group I (control-untreated), Group II (CBZ-control), Group III (VE-control), Group IV (CBZ + VE-control), Group V (levothyroxine-induced testicular injury), Group VI (levothyroxine + CBZ-treated), Group VII (levothyroxine + VE-treated), and Group VIII (levothyroxine + CBZ + VE-treated). The study was conducted in the Faculty of Medicine, Suez Canal University (Ismailia, Egypt). After cervical decapitation, both testes and epididymis were examined histopathologically and immunohistochemically. Significant differences were observed among groups concerning malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT; all P < 0.001). Polymerase chain reaction analysis showed significant differences in tumor necrosis factor-α (TNF- α ), interleukin-10 (IL-10), Bcl-2-associated X protein (BAX), B-cell lymphoma 2 protein (Bcl2), p53, Caspase-3, Caspase-8, Caspase-9, and nuclear factor-kappa B (NF- κ B) mRNA levels (all P < 0.001). Hyperthyroid group treated with CBZ alone (Group VI) exhibited testicular side effects, affecting seminiferous tubules and spermatogenesis. However, the Group VIII showed improved spermatogenesis and a decrease in testicular side effects. The addition of VE to the treatment of hyperthyroid rats with CBZ reduced testicular side effects and seminiferous tubular affection when potentially improving spermatogenesis. Further research is needed to elucidate the underlying mechanisms fully.

Antioxidant effects of α-lipoic acid against epididymal oxidative damage in adult offspring rats exposed to maternal hypothyroidism stress

It is well known that the epididymis promotes post-testicular sperm maturation events. However, its malfunction during congenital hypothyroidism is relatively less understood as compared to the testis. The present study evaluated the probable effect of α-lipoic acid on epididymal oxidative stress parameters in rats exposed to antithyroid drug, carbimazole during fetal period. Time-mated pregnant rats in unexposed and carbimazole (1.35 mg/Kg body weight exposed were allowed to deliver pups and weaned. At postnatal day 100, the F1 male pups were assessed for epididymal endpoints. Among the epididymal regions, significant elevation of lipid peroxidation levels, superoxide anion, and hydrogen peroxide contents with a concomitant reduction in the activity levels of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and reduced glutathione levels were observed in cauda epididymis of carbimazole exposed rats over controls. Significant elevation in sperm DNA fragmentation (comet assay), accelerated cauda epididymal sperm transit time and reduction in epididymal sialic acid content was observed in carbimazole exposed rats. RT-qPCR studies revealed that embryonic exposure to carbimazole resulted in down regulation of androgen receptor, nuclear factor eryrthoid 2 like 2, 5α-reducatse 1 mRNA levels, while up regulation of caspase 3 mRNA was observed in epididymal regions of rats. In addition, fetal exposure to carbimazole resulted in disorganization of cauda epididymal architecture in rats. Conversely, supplementation of α-lipoic acid (70 mg/Kg bodyweight) during PND 3 to 14 restored epididymal functions in carbimazole exposed rats and the ameliorative effects of lipoic acid could be attributed to its antioxidant and steroidogenic effects.

Immunostimulatory and anti-inflammatory impact of Fragaria ananassa methanol extract in a rat model of cadmium chloride-induced pulmonary toxicity

Cadmium is an extremely dangerous heavy metal that can lead to disastrous consequences in all organisms. Several natural remedies reduce the toxicities of experimentally generated metals in animals. Strawberry Fragaria ananassa contains several bioactive compounds that may mitigate heavy-metal toxicity. The study aim was to evaluate the ability of a strawberry fruit methanol extract (SE) to reduce Cd toxicity and to identify and quantify the active constituents of SE. Forty Wistar rats were classified into four groups: the control group- 1 ml saline IP; SE group- 100 mg of SE/kg rats orally; cadmium (Cd) group-2 mg CdCl2/kg body weight/IP daily; and treated group- SE given 1 hour before Cd administration. Administration of Cd induced several histopathological and immunohistochemical alterations in lung sections. Biochemical analysis of lung homogenates and mRNA levels of antioxidants and inflammatory cytokines indicated significant changes to the risk profile. SE administration significantly decreased the oxidative stress, inflammation, tissue damage, the mean area percentage of collagen fibers, and positive immuno-expressions of TNF-α and NF-κB induced by CdCl2. Moreover, the MDA, TNF-α, GM-CSF, and IL-1β levels in Cd-exposed rat lung tissue were significantly lower in the SE-treated group than in the Cd-group. SE significantly augmented lung GSH, SOD, HO-1, GPx-2, and Nrf2 levels in Cd-exposed rats. SE mitigated Cd-caused oxidative stress and lung inflammation. Therefore, regularly consuming a strawberry-rich diet could benefit general health and help prevent and treat diseases.

Transcriptomic profiling identified altered expression of genes associated with testicular functions in adult F1 rats exposed to carbimazole during fetal period

The central goal of this study was to investigate the alterations in transcriptome of testis in F1 generation adult rats exposed to carbimazole prenatally. At post-natal day 100, the testis of rats delivered to carbimazole exposed (time-mated pregnant rats orally administered with carbimazole from gestation day 9 to 21) and control (untreated pregnant rats) groups were subjected to transcriptomic analysis using NGS platform. A total of 187 differentially expressed (up regulated: 49 genes; down regulated: 138) genes were identified in carbimazole exposed rats over controls and the major processes associated with these altered testicular transcripts were examined. Functional clustering analysis suggest that the involvement of identified DEGs were linked to intrinsic and extrinsic apoptotic pathways, mitochondrial solute carriers slc25a members, nuclear receptors/zinc family members, steroidogenic pathway and cholesterol synthesis, and growth factors and protein kinases and thus represent potential mediators of the developmental toxic effects of carbimazole in F1 generation rats. Based on the findings, it can be concluded that prenatal exposure to carbimazole prominently affects expression of multiple transcripts implicating key regulatory events associated with testicular functions, spermatogenesis and steroidogenesis in rats at their adulthood. These results support our earlier findings and hypothesis. This background information obtained at the testicular transcriptome during gestational hypothyroidism might be helpful for future studies and experiments to gain additional in-depth analysis and to develop strategies to protect F1 generation male reproductive health. SIGNIFICANCE: The rationale for the paper described thyroid gland changes in the off springs. Antithyroid drugs are widely used to control thyroid disorders and used to control thyroid hormone levels during surgeries. Carbimazole is one of the antithyroid drugs and is a parent molecule of methimazole. Both the drugs can able to cross placenta. During fetal period, the development of thyroid gland is not completely formed and hence, the fetus entirely depends on the maternal thyroid hormones. Therefore, it is conceivable that the disturbances at the level of maternal thyroid hormones could interfere with the development of vital organs such as testis and glands including thyroid gland (Kala et al., 2012). To address this notion, the present study was designed and executed.

Selenium nanoparticles and omega-3 fatty acid enhanced thermal tolerance in fish against arsenic and high temperature

The aquatic ecosystem is prone to global climate change and pollution affecting aquatic animals, including fish. In light of the above, we experimented with delineate the role of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) with selenium nanoparticles (Se-NPs) to enhance the thermal tolerance in Pangasianodon hypophthalmus reared under control or concurrent exposure to high temperature and arsenic (As + T) for 112 days. Se-NPs were synthesized using the green approach. Four experimental diets viz. EPA + DHA at 0.2, 0.4 and 0.6 % along with Se-NPs at 0.2 mg kg^-1 diet were formulated and prepared. End of the experiment (112 days), the thermal tolerance viz. CTmin (critical thermal minima) CTmax (critical thermal maxima), LTmin (lethal thermal minima) and LTmax (lethal thermal maxima) were determined. Supplementation of EPA + DHA along with Se-NPs noticeably improved the thermal tolerance of the fish reared under stress (As + T) and control condition. Superoxide dismutase, glutathione-s-transferase, catalase, glutathione peroxides and LPO were enhanced by As + T, whereas EPA + DHA at 0.4 % and Se-NPs reduced the oxidative stress. Further, acetylcholine esterase was inhibited by arsenic alone and concurrent with temperature but dietary supplementation significantly enhanced the brain AChE activity. Exposure to arsenic and concurrent with a temperature significantly reduced the ATPase. Whereas supplementation of EPA + DHA at 0.4 % and Se-NPs enhanced the ATPase in liver and gill tissues. Arsenic bioaccumulation was also reduced with EPA + DHA at 0.4 % and Se-NPs. The present investigation concluded that EPA + DHA at 0.4 % and Se-NPs at 0.2 mg kg^-1 diet protects the P. hypophthalmus against arsenic pollution and thermal stress.

Metformin alleviates the dysregulated testicular steroidogenesis and spermatogenesis induced by carbimazole in levothyroxine-primed rats

Most of the published experiments about carbimazole (CMZ)-induced testicular injury are constructed in normal healthy animals, which lakes the translational identification. Despite metformin (MET) having advantageous effects on injured testicles, its impact on thyroid function is arguable. In the current levothyroxine (LT4)/CMZ model, Wistar rats were primed by LT4 for sixty days. CMZ was then given individually or simultaneously with different doses of MET, 100, 200, and 400 mg, daily for thirty days. Serum was assessed for thyroid profile panel, sex hormones, and gonadotropin levels. Testicular tissues were examined for steroidogenesis, spermatogenesis, inflammation, and apoptosis. Histopathology of thyroid and testes were examined, besides thyroidal nuclear factor (NF)-kB expression. MET in a dose-response manner improved the LT4/CMZ-induced testicular toxicity by increasing the steroidogenic acute regulatory protein (StAR), and 17-β-hydroxysteroid dehydrogenase (17βHSD) activities, the proliferating cell nuclear antigen (PCNA), sperm count and motility, sex hormones, and gonadotropin levels. MET-400 mg markedly decreased the elevated NF-kB expressions, tumour necrosis factor (TNF)-α, caspase-3, and BAX, and increased BCL-2. LT4/CMZ could be used as translational animal modelling. MET displayed a dose-dependent ameliorative effect on the LT4/CMZ model without significant harmful effects on thyroid functions. MET-testicular protective roles in diabetics with thyroidal diseases should be explored.

Antioxidant role of selenium against maneb-induced cardiotoxicity in mice

The current study was conducted to assess the beneficial effect of selenium (Se) on maneb-induced cardiotoxicity and fatty acid alterations in adult mice. Swiss albino male mice were assigned into four experimental groups. The first group consisted of negative controls. The second group represented the positive controls where mice received daily, via the diet, sodium selenite at a dose of 0.2 mg/kg. For the third group, mice were subjected to intraperitoneal injections of maneb (30 mg/kg BW). The fourth group (MB+Se) received daily the same dose of maneb as group 3 along with sodium selenite at the same dose as group 2. Mice exposure to maneb caused cardiotoxicity as indicated by an increase in malondialdehyde, hydrogen peroxide, and protein carbonyl levels, and an alteration of the antioxidant defense system (catalase, glutathione peroxidase, superoxide dismutase, glutathione, and vitamin C). Plasma lactate dehydrogenase activity and total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels increased, while high-density lipoprotein cholesterol level decreased. Results showed also a decrease in the amount of n-3 PUFA, docosahexaenoic, docosapentaenoic, and eicosapentaenoic acids. However, an increase in the levels of MUFA, cis-vaccenic, and palmitoleic acids was observed. Co-administration of Se restored the parameters indicated above to near control values. The histopathological findings confirmed the biochemical results. Selenium could be a useful and efficient agent against maneb-induced cardiotoxicity.

Protective Effect of Sodium Selenite on 4-Nonylphenol-Induced Hepatotoxicity and Nephrotoxicity in Rats

This study was aimed at evaluating the protective effect of sodium selenite (SS) on DNA integrity, antioxidant/oxidant status, and histological changes on 4-nonylphenol (4-NP)-induced toxicity in liver and kidney tissues of rats. Twenty-four adult male Sprague Dawley rats were divided into 4 groups as control, SS, 4-NP, and SS+4-NP group. Control group was untreated. The SS group was supplemented with SS (0.5 mg/kg/day) and the 4-NP group was given 4-NP (125 mg/kg/day). The rats in the SS+4-NP group received SS followed by 4-NP 1 h later at the abovementioned doses. The treatments were administered by oral gavage for 48 days. DNA damage was analyzed by comet assay in lymphocytes. Oxidative stress parameters were measured, and histological evaluation was performed in liver and kidney tissues. Results showed that SS administration significantly decreased % Tail DNA and Mean Tail Moment in SS+4-NP group as compared with 4-NP group. Catalase activity in liver was significantly lower in 4-NP group only. SS treatment significantly increased the glutathione level and decreased high malondialdehyde level in tissues of the SS+4-NP group as compared with 4-NP group. Dilation of central vein, ballooning degeneration, vacuolar degeneration, and deterioration in the structure of remark cords in 4-NP-administered were alleviated in rats that received SS supplementation before administration of 4-NP. Moreover, glycogen intensity in hepatocytes and the wall of central vein increased in the SS+4-NP group. In addition, the SS supplementation in the SS+4-NP group decreased glomerular degeneration as well as the width of cavum glomeruli and congestion intensity in the kidney. These results indicate that SS may have a protective effect against 4-NP-induced hepato-nephrotoxicity in rats.

Selenomethionine administration decreases the oxidative stress induced by post mortem ischemia in the heart, liver and kidneys of rats

Selenium is an essential element in human and animal metabolism integrated into the catalytic site of glutathione peroxidase (GPX1), an antioxidant enzyme that protects cells from damage caused by reactive oxygen species (ROS). Oxidative stress refers the imbalance between ROS and antioxidant defense systems. It generates alterations of DNA, proteins and lipid peroxidation. The imbalance occurs particularly during ischemia and lack of postmortem perfusion. This mechanism is of relevance in transplant organs, affecting their survival. The aim of this research is to evaluate the effect of seleno-methionine (SeMet) as a protective agent against postmortem ischemia injury in transplant organs. Wistar rats were orally administered with SeMet. After sacrifice, liver, heart and kidney samples were collected at different postmortem intervals (PMIs). SeMet administration produced a significant increase of Se concentration in the liver (65%, p < 0.001), heart (40%, p < 0.01) and kidneys (45%, p < 0.05). Levels of the oxidative stress marker malondialdehyde (MDA) decreased significantly compared to control in the heart (0.21 ± 0.04 vs. 0.12 ± 0.02 mmol g^-1) and kidneys (0.41 ± 0.02 vs. 0.24 ± 0.03 mmol g^-1) in a PMI of 1-12 h (p < 0.01). After SeMet administration for 21 days, a significant increase in GPX1 activity was observed in the liver (80%, p < 0.001), kidneys (74%, p < 0.01) and heart (35%, p < 0.05). SeMet administration to rats significantly decreased the oxidative stress in the heart, liver and kidneys of rats generated by postmortem ischemia.

Impact of platelet-rich plasma versus selenium in ameliorating induced toxicity in rat testis: histological, immunohistochemical, and molecular study

This study was conducted on forty adult rats divided into four groups: Group I (control) that is divided into subgroups A, B, and C and Group II (methotrexate (MTX)-treated); the rats were injected intraperitoneally with MTX at a dose of 1 mg/kg/week, for 8 weeks. Group III (MTX-Se co-treated) was injected with MTX like Group II plus an oral administration of selenium at a dose of 10 μg/kg b.w/day, for 8 weeks. Group IV (MTX-PRP co-treated), rats were injected intraperitoneally with MTX like Group II plus platelet-rich plasma (PRP) injection under the scrotum, three times with 2-week intervals (volume-0.1 ml per injection) and euthanized after 8 weeks. Histological, immunohistochemical, and genetic expression using qPCR and western blotting technique were conducted. There was improvement in histological structure of testes in most specimens of Group IV. The latter group revealed a significant decrease in Bax and an increase in Bcl-2. The regeneration of testicular tissue was more observed in Group IV as measured by an increase in mean number of PCNA. Moreover, Group IV revealed an increased genetic level of FSCN3, GCNF, UBQLN3, and DAZL. Both MTX-Se and MTX-PRP have an anti-inflammatory effect as measured by a reduction in NF-κb. The anti-oxidative effect of selenium and PRP was noticed by a decrease in the level of the iNos and an increase in eNos protein and the autophagy marker LC3. PRP has ameliorative effects on induced rat testicular toxicity as evaluated by morphological changes and confirmed by immunohistochemical reactions, genetic expression, and western blotting analyses including oxidative and anti- oxidative markers.

Protective effects of nuclear factor erythroid 2-related factor on oxidative stress and apoptosis in the testis of mice before adulthood

Oxidative stress disrupts the intracellular redox balance that modulate many signaling pathways, including nuclear factor erythroid 2-related factor 2 (Nrf2)/Keap1 signaling. However, the antioxidant roles of Nrf2 in the testis before adulthood have not been reported. Accordingly, in this study, we aimed to investigate the effects of the Nrf2 antioxidant system on protection of testicular cells against oxidative stress at different stages of development in the testis of mice before adulthood. Male mice (1, 2, 4, and 8 weeks old) were used, and their relative testes weights were calculated. Malondialdehyde (MDA) contents and superoxide dismutase (SOD) activity were detected to evaluate the antioxidant capacity in the testes. Additionally, Nrf2 signaling pathway and mitochondrial apoptotic pathway proteins were evaluated by western blotting, and the localizations of Nrf2, protein gene product (PGP) 9.5, and activated-caspase 3 in testicular cells were examined using immunohistochemistry. The results showed that the activities of caspase-8 and caspase-3 and the number of activated-caspase 3-positive testicular cells per tubule were increased after 1 week of age. Moreover, MDA contents were increased and SOD activity was decreased with age in mouse testes before adulthood. The expression of PGP9.5 was increased, as well as the number of positive testicular cells per tubule. In addition, Nrf2 translocation to the nuclei of testicular cells also increased, accompanied by activation of the Nrf2/Keap1 signaling pathway. Moreover, nuclear factor-κB was inhibited, and the mitochondrial apoptotic pathway was activated in mouse testes before adulthood. Overall, our findings demonstrated that oxidative stress increased with age in mouse testes before adulthood and that oxidative stress could induce apoptosis in testicular cells. However, testicular cells are still in a rapid proliferative state owing to the antioxidant protection of Nrf2. Thus, our study provided new insights into oxidative stress-mediated impairment of spermatogenesis with age in mouse testes before adulthood and evidence for the protective role of Nrf2 in male fertility.

Selenium protection against mercury toxicity on the male reproductive system of Clarias gariepinus

The present study aimed to evaluate the protective role of Selenium (Se) (0.1 ppm) on the male reproductive system of the catfish Clarias gariepinus exposed to sublethal doses of Mercury (Hg) (0.04 and 0.12 ppm) for 30 days. Indicators of seminal and gonadal hormone disruption (testosterone, estradiol and 11 keto testosterone), antioxidants (total antioxidant capacity (TAO), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)), oxidative stress biomarkers (lipid peroxidation (LPO), percentage of DNA fragmentation, carbonylated proteins (CP) and nitric oxide (NO)) and histopathological alterations in testicles of Clarias gariepinus were determined. The exposure to Hg resulted in a high accumulation of residues of this metal in testicular tissues. The results showed a significant decrease in sperm count, activity and motility and in all gonadal hormones in Hg exposed groups. Hg exposure also induced a decline in TAO, SOD, CAT and GPx, whereas LPO, DNA fragmentation, CP and NO significantly increased in testicles of C. gariepinus respect to the control group. Although exposure to Se did not reduce the degree of mercury bioconcentration in the testicles, the sperm quality parameters were recovered. Moreover, TAO levels and GPx activity significantly increased after fish exposure to Se, whereas CP levels decreased. LPO, NO, CAT and SOD were also partially normalized when compared with the groups exposed to only Hg. In conclusion, the results showed that Hg, even in the small doses is capable to induce reproductive toxicity in the male catfish. Se exposure partially restored the values of biochemical parameters and sperm quality in Hg-treated fish suggesting protective effects against Hg reproductive toxicity.

Effect of both selenium and biosynthesized nanoselenium particles on cadmium-induced neurotoxicity in albino rats

Because cadmium (Cd) is not naturally degradable by ecosystems, it interferes with many types of food chains. Cd accumulates in the kidney, liver and in the nervous tissues, especially the brain. The neurotoxicity of Cd is very high, as it alters the integrity, and increases the permeability, of the blood–brain barrier. Cd penetrates and accumulates in neurons in the brains of rats. This study reveals that Cd decreases antioxidant enzymes and increases oxidative stress in the brain. In addition, Cd increases lipid peroxidation of brain tissues. Cd increases the expression of the Cu/Zn superoxide dismutase gene. It also affects cholinergic, glutamatergic, gamma-Aminobutyric acid (GABAergic), dopamine, serotonin and acetylcholine neurotransmitters in brain tissue. Consequently, Cd increases the formation of amyloid β, a neurotoxic index, and induces apoptosis by changing the quality and the quantity of Bcl-2, Bax and p53 proteins. In conclusion, both selenium and nanoselenium show potential antioxidant activity and promote recovery from the neurotoxic action of Cd.

Trace elements content in semen and their interactions with sperm quality and RedOx status in freshwater fish Cyprinus carpio: A correlation study

Objective of the present study was to investigate interactions between trace elements content and RedOx status, as well as sperm quality parameters (motility features, DNA fragmentation) in fish spermatozoa in natural conditions. Reproductively mature male freshwater fish (n = 16) of Cyprinus carpio breed were used in the study. Trace elements content was determined in fish milt samples by inductively-coupled plasma optical emission spectrometry (ICP-OES) and by cold-vapor atomic absorption spectroscopy (CV-AAS). Sperm quality evaluation was realized by computer-assisted sperm analysis (CASA) quantifying several parameters: concentration, total motility, progressive motility, distance average path, distance curved line, distance straight line, velocity average path, velocity curved line, velocity straight line, straightness, linearity, amplitude of lateral head displacement and beat cross frequency. The general scheme of descending concentrations of trace metals in semen samples was following: Zn > Fe > Cu > As > Sr > Ni > Mn > Se > Pb > Cr > Cd > Hg. Total motility of spermatozoa was relatively high (91.45%), however progressive motility was not even half of this value (39.47%). Sperm DNA fragmentation values were relatively low (4.00-6.29%). The percentage of immotile spermatozoa showed a significant correlation with all RedOx status parameters and also with DNA fragmentation. Positive statistically significant correlations were observed between trace elements (Mn, Se, Sr, and Zn) and some qualitative spermatozoa parameters (velocity and distance parameters). Cu and Hg content shows similar negative associations with progressive motility. Hg also interacted with production of malondialdehyde. Overall, the present study suggests application of multi-component mixtures of environmentally related trace elements concentrations when assessing the potential reproductive risk.

The Ameliorating Effect of Sodium Selenite on the Histological Changes and Expression of Caspase-3 in the Testis of Monosodium Glutamate-Treated Rats: Light and Electron Microscopic Study

Monosodium glutamate (MSG) is a commonly used flavor enhancer that may contribute to male infertility. Sodium selenite is inorganic chemical form of selenium (Se). Se is best known as an antioxidant. This study was designed to investigate the possible ameliorating role of sodium selenite against MSG-induced testicular toxicity and histological changes. Forty male albino rats were allocated into four groups. Control group received distilled water, SE group received sodium selenite (0.25 mg/kg/day) dissolved in distilled water orally, MSG group received MSG (6 mg/g/day) dissolved in distilled water orally, and MSG + SE group received both MSG and sodium selenite for 45 days. Testicular samples were prepared for biochemical, light, and electron microscopic studies. Immunohistochemical staining for caspase-3 was done. MSG group demonstrated a significant increase in malondialdehyde level, marked damage of seminiferous tubules with a significant reduction in diameter and height of the lining epithelium. Spermatogenic cells showed disorganization, dark nuclei, reduction in number, and maturation arrest. Vacuolations of interstitial tissue and Leydig cells were also observed. Percent area of fibrosis and caspase-3 immunoexpression was significantly increased. Ultrastructurally, irregular tubular basement membrane and damaged germ cells were found. The spermatogenic, Sertoli, and Leydig cells showed irregular shrunken nuclei, cytoplasmic vacuolations, and swollen mitochondria. MSG + SE group showed much better histological and ultrastructural picture and improvement of the measured biochemical and morphometric parameters. Percent area of caspase-3 immunoexpression was significantly decreased. In conclusion, sodium selenite ameliorated the testicular damaging effect of MSG through reduction of oxidative stress and apoptosis.

Protective Effect of Selenium on Aflatoxin B1-Induced Testicular Toxicity in Mice

Aflatoxins have been considered as one of the major risk factors of male infertility, and aflatoxin B1 (AFB1) is the most highly toxic and prevalent member of the aflatoxins family. Selenium (Se), an essential nutritional trace mineral for normal testicular development and male fertility, has received extensive intensive on protective effects of male reproductive system due to its potential antioxidant and activating testosterone synthesis. To investigate the protective effect of Se on AFB1-induced testicular toxicity, the mice were orally administered with AFB1 (0.75 mg/kg) and Se (0.2 mg/kg or 0.4 mg/kg) for 45 days. We found that that Se elevated testes index, sperm functional parameters (concentration, malformation, and motility), and the level of serum testosterone in AFB1-exposed mice. Moreover, our results showed that Se attenuated the AFB1-induced oxidative stress and the reduction of testicular testosterone synthesis enzyme protein expression such as steroidogenic acute regulatory protein (StAR), P450 side-chain cleavage (P450scc), and 17β-hydroxysteroid dehydrogenase (17β-HSD) in AFB1-exposed mice. These results demonstrated that Se conferred protection against AFB1-induced testicular toxicity and can be attributed to its antioxidant and increased testosterone level by stimulating protein expression of StAR and testosterone synthetic enzymes.

Effect of selenium on testicular damage induced by varicocele in adult male Wistar rats

PROJECT

Varicocele is an abnormal tortuosity and distension of the veins of the pampiniform plexus in the spermatic cord. It is the most common surgically correctable cause of male infertility. Several studies have revealed the effects of increased oxidative stress on serum, semen, and testicular tissues in patients with varicocele or in animal models. The aim of this study was to investigate the effects of sodium selenite on testicular damage induced by experimental left varicocele in male Wistar rats.

PROCEDURE

In the present study, the effects of oral administration of sodium selenite (at doses of 0.05, 0.1, 0.2, and 0.4mg/kg bw) were assessed in normal and varicocelized rats.

RESULTS

The varicocelized control rats showed decrease in sperm quality parameters, decreased activity of testes CAT, GPX and SOD, increased levels of MDA, and damage in testicular architecture. Administration of sodium selenite significantly reduced these changes to nearly normal levels, but did not change these parameters in normal rats. Histopathological studies further confirmed the protective effects of sodium selenite on varicocele-induced testicular damage in rats. Administrations of sodium selenite did not change these parameters in normal rats.

CONCLUSIONS

Taken together, the results of this study suggest that sodium selenite treatment may have beneficial effect on the testes of varicocelized rats.

α-lipoic acid inhibits oxidative stress in testis and attenuates testicular toxicity in rats exposed to carbimazole during embryonic period

•

The intrauterine exposure of carbiamzole (CBZ) on male fertility is not well defined.

•

CBZ exposure in utero results in spermatotoxic effects and impaired steroidogenesis in offspring rats at their adulthood.

•

Gestational exposure to CBZ augmented testicular oxidative damage in offspring rats.

•

α-lipoic acid supplementation with its antioxidant properties ameliorated diminished male reproductive health in rats exposed to CBZ prenatally.

The aim of this study was to evaluate the probable protective effect of α-lipoic acid against testicular toxicity in rats exposed to carbimazole during the embryonic period. Time-mated pregnant rats were exposed to carbimazole from the embryonic days 9–21. After completion of the gestation period, all the rats were allowed to deliver pups and weaned. At postnatal day 100, F1 male pups were assessed for the selected reproductive endpoints. Gestational exposure to carbimazole decreased the reproductive organ indices, testicular daily sperm count, epididymal sperm variables viz., sperm count, viable sperm, motile sperm and HOS-tail coiled sperms. Significant decrease in the activity levels of 3β- and 17β-hydroxysteroid dehydrogenases and expression of StAR mRNA levels with a significant increase in the total cholesterol levels were observed in the testis of experimental rats over the controls. These events were also accompanied by a significant reduction in the serum testosterone levels in CBZ exposed rats, indicating reduced steroidogenesis. In addition, the deterioration of the testicular architecture and reduced fertility ability were noticed in the carbimazole exposed rats. Significant reduction in the activity levels of superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and reduced glutathione content with a significant increase in the levels of lipid peroxidation were observed in the testis of carbimazole exposed rats over the controls. Conversely, supplementation of α-lipoic acid (70 mg/Kg bodyweight) ameliorated the male reproductive health in rats exposed to carbimazole during the embryonic period as evidenced by enhanced reproductive organ weights, selected sperm variables, testicular steroidogenesis, and testicular enzymatic and non-enzymatic antioxidants. To conclude, diminished testicular antioxidant balance associated with reduced spermatogenesis and steroidogenesis might be responsible for the suppressed reproduction in rats exposed to the carbimazole transplacentally. On the other hand, α-lipoic acid through its antioxidant and steroidogenic properties mitigated testicular toxicity which eventually restored the male reproductive health of carbimazole-exposed rats.

Effect of various selenium doses on chromium(IV)-induced nephrotoxicity in a male chicken model

Our study aimed to explore whether Na₂SeO₃ (Se) can alleviate the nephrotoxicity induced by K₂Cr₂O₇ [Cr(VI)]. One hundred and five male chickens were randomly divided into seven groups with 15 chickens each group: The 6 experimental groups received K₂Cr₂O₇ alone or in combination with 0.31, 0.63, 1.25, 2.50, and 5.00 mg/kg for 42 days, respectively, while control group was treated with equivalent water. Exposure to Cr(VI) significantly increased MDA contents and organ coefficient, whereas decreased T-SOD activities, Ca²⁺-ATPase activities, mitochondrial membrane potential and GSH contents, and histological studies demonstrated renal damage. Above indicators were restored by Se supplement (0.31, 0.63, and 1.25 mg/kg), in which supplement with 0.63 mg/kg Se developed more effectively than the other two groups; on the contrary, in the groups of Se supplement with 2.50 and 5.00 mg/kg, the above indicators were not ameliorated and even exacerbated. This study demonstrated that Cr(VI) can result in kidney oxidative damage in male chickens, and Se of certain dose has the protective effects against Cr(VI)-induced nephrptoxicity.

Selenium Polysaccharide SPMP-2a from Pleurotus geesteranus Alleviates H2O2-Induced Oxidative Damage in HaCaT Cells

Selenium- (Se-) enriched polysaccharide SPMP-2a was extracted and purified from Pleurotus geesteranus. SPMP-2a is a white flocculent polysaccharide and soluble in water, with a molecular weight of 3.32 × 10⁴ Da. Fourier transform infrared spectroscopy spectral analysis indicated that it belongs to an acid Se polysaccharide with α-D-glucopyranoside bond. The effects of Se polysaccharide SPMP-2a in P. geesteranus against hydrogen peroxide- (H₂O₂-) induced oxidative damage in human keratinocytes (HaCaT) cells were evaluated further. Reduced cell viability and elevated apoptotic rates in H₂O₂-treated HaCaT cells were proven by MTT and flow cytometry assays. Hoechst 33342 staining revealed chromatin condensations in the nuclei of HaCaT cells. However, with the addition of SPMP-2a, cell viability improved, nuclear condensation declined, and cell apoptotic rates dropped significantly. Ultrastructural observation consistently revealed that treatments with SPMP-2a reduced the number of swollen and vacuolar mitochondria in the H₂O₂-treated cells compared with the controls. Furthermore, SPMP-2a increased the superoxide dismutase (SOD) and catalase (CAT) activities and reduced reactive oxygen species (ROS) content. Western blot analysis showed that SPMP-2a treatment effectively increased B-cell lymphoma 2 (Bcl-2) protein expression. Therefore, SPMP-2a could improve cellular antioxidant enzyme activities, reduce ROS levels, and increase Bcl-2 protein expression levels, thereby reducing cell apoptosis and protecting HaCaT cells from H₂O₂-induced oxidative damage.

The Protective Effect of Selenium on Chronic Zearalenone-Induced Reproductive System Damage in Male Mice

This study aims to explore the protective effect of selenium (Se) on chronic zearalenone (ZEN)-induced reproductive system damage in male mice and the possible protective molecular mechanism against this. The chronic ZEN-induced injury mouse model was established with the continuous intragastric administration of 40 mg/kg body mass (B.M.) ZEN for 28 days. Then, interventions with different doses (0.1, 0.2, and 0.4 mg/kg B.M.) of Se were conducted on mice to analyse the changes in organ indexes of epididymis and testis, antioxidant capability of testis, serum level of testosterone, sperm concentration and motility parameters, and the expression levels of apoptosis-associated genes and blood testis barrier- (BTB) related genes. Our results showed that Se could greatly improve the ZEN-induced decrease of epididymis indexes and testis indexes. Results also showed that the decrease in sperm concentration, sperm normality rate, and sperm motility parameters, including percentage of motile sperm (motile), tropism percentage (progressive) and sperm average path velocity (VAP), caused by ZEN were elevated upon administration of the higher dose (0.4 mg/kg) and intermediate dose (0.2 mg/kg) of Se. Selenium also significantly reduced the content of malondialdehyde (MDA) but enhanced the activities of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) in the testis tissue. Further research demonstrated that ZEN increased the level of mRNA expression of BCL2-associated X protein (Bax) and caspase 3 (Casp3), decreased the level of mRNA expression of B cell leukemia/lymphoma 2 (Bcl2), vimentin (Vim) and cadherin 2 (Cdh2), whereas the co-administration of Se reversed these gene expression levels. Our results indicated that high levels of Se could protect against reproductive system damage in male mice caused by ZEN and the mechanism might such be that Se improved mice antioxidant ability, inhibited reproductive cell apoptosis, and increased the decrease of BTB integrity-related genes caused by ZEN.

Effect of separate and combined exposure of selenium and diazinon on rat sperm motility by computer assisted semen analysis

Effects of selenium (Se) and diazinon (DZN) on sperm motility parameters in rats were investigated. Male rats received a separate dose of Se (2mgkg^-1 b.w., intraperitoneally, 5mgL^-1, per os in drinking water), diazinon (20mgkg^-1 b.w., intraperitoneally, 40mgL^-1, per os in drinking water), and in combination (Se+DZN) with the same dosage as in the separate administration. 36h an intraperitoneal (i.p.) and after 90days of per oral (p.o.) exposure, thirteen parameters of sperm motility were evaluated using a Computer Assisted Sperm Analyzer (CASA). Almost all the evaluated sperm motility parameters significantly decreased in Se p.o. exposed groups. In the Se i.p. group decrease was noted only in beat cross frequency (BCF) and progressive motility. Significant decline in the sperm motility, progressive motility, BCF and increase in amplitude of lateral head displacement (ALH) were recorded after DZN i.p. administration. In DZN p.o. group, significant increase in ALH, velocity average path (VAP) and curvilinear velocity (VCL) but decrease in progressive motility and BCF was detected. Se+DZN i.p. administration caused a significant decrease in motility, progressive motility and BCF. Per oral administration of Se+DZN decreased all motility parameters except LIN, WOB and ALH. Sperm abnormalities increased in all experimental conditions. Se and DZN negatively affected sperm structure and function in separate doses or in combination. No protective effect of Se was observed.

Nephrotoxic effects of lead nitrate exposure in diabetic and nondiabetic rats: Involvement of oxidative stress and the protective role of sodium selenite

Heavy metals are known to be toxic to organisms. The present study was undertaken to evaluate the protective effect of sodium selenite against lead nitrate (LN)-induced nephrotoxicity in diabetic and nondiabetic rats. Animals were divided into eight groups where the first was served as a control, whereas the remaining groups were treated with sodium selenite (1 mg/kg b.w.), LN (22.5 mg/kg b.w.) and a combination of LN and sodium selenite and diabetic forms of these groups. Changes in antioxidant enzyme activities, malondialdehide levels, serum urea, uric acid, creatinine levels, body, and kidney weights and histopathological changes were determined after 28 days. LN caused severe histopathological changes, increment in urea, uric acid, creatinine, and MDA levels, also decreasing in antioxidant enzyme activities, body, and kidney weights. In sodium selenite + LN group, we observed the protective effect of sodium selenite on examining parameters. Also diabetes caused alterations on these parameters compared with nondiabetic animals. We found that sodium selenite did not show protective effect on diabetes caused damages. As a result, LN caused nephrotoxicity and sodium selenite alleviated this toxicity but sodium selenite did not protect kidneys against diabetes mediated toxicity. Also, LN caused more harmfull effects in diabetic groups compared with nondiabetic groups. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1229-1240, 2016.

Ameliorative effect of selenium in cisplatin-induced testicular damage in rats

In this study, we investigated the protective effect of selenium (Se) on cisplatin (Cis) induced testicular damage using histopathological, immunohistochemical and biochemical approaches. Twenty-one male Wistar rats were equally divided into three groups of seven rats each: control (C), Cis, and Cis+Se. Cis and Cis+Se group rats received Cis at a dose of 12mg/kg b.w./day, intraperitoneally for 3 consecutive days. Cis+Se group rats received selenium via oral gavage 3mg/kg/day (twice-a day as 1.5mg/kg) until 11th consecutive days starting at 5 days before cisplatin injection. C group received only 0.9% NaCl intraperitoneally and orally at same time and at equal volume. After the treatment, the histopathological, immunohistochemical and biochemical examinations were performed. In seminiferous tubules of Cis treated rats were observed the most consistent findings characterized with vacuolization, desquamation, disorganization, and also was a considerable reduction in elongated spermatids, however the Cis+Se group exhibited improved histopathologic changes. In the immunohistochemical examinations, caspase-3 immunopositive cells displayed higher in the Cis group according to C and Cis+Se groups. Bcl-2 and NF-κB staining revealed a moderate number in the C group and significantly fewer in the Cis group compared to the Cis+Se groups. Additionally, MDA levels were also significantly increased in the Cis group in comparison to Control group, but pretreatment with selenium prevented elevation of MDA levels significantly in Cis+Se group rats. This study indicates that Cis-treatment induced testicular apoptosis and lipid peroxidation, and combined treatment with selenium prevented severity of the toxicity in rats.

Effects of lead nitrate and sodium selenite on DNA damage and oxidative stress in diabetic and non-diabetic rat erythrocytes and leucocytes

The adverse effects of lead nitrate (LN) and the preventive role of sodium selenite were investigated in diabetic and non-diabetic rat blood by measuring trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) also by evaluating DNA damage with comet assay. LN increased the levels of MDA, tail DNA%, mean tail length and tail moment, decreased the enzymes activities, FRAP and TEAC values. In sodium selenite+LN group, we observed the protective effect of sodium selenite on examining parameters. Diabetes caused alterations on these parameters, too. We found that sodium selenite did not protect against diabetes caused damages. As a result, LN caused toxic effects on blood cells and sodium selenite alleviated this toxicity but it did not show preventive effect against diabetes. Also, LN caused more harmfull effects in diabetic groups than non-diabetic groups.

Impact of L-carnitine and Selenium Treatment on Testicular Apoptosis in Rats Exposed to 2.45 GHz Microwave Energy

OBJECTIVE

It has been suggested that electromagnetic radiation (EMR) by wireless devices (2.45 GHz) induces testicular apoptosis. We investigated if supplemental selenium (Se) and L-carnitine may reduce this adverse effect.

MATERIAL

Twelve-week old male Wistar albino rats were used in this study. Twenty-four rats were equally divided into four groups which were named as: sham group, EMR-only, EMR+L-carnitine (1.5 mg L-carnitine/kg/day) and EMR+Se (1.5 mg Se/kg/-every other day).

RESULTS

The level of Bcl-2, Bax, caspase-3 and -8 were compared and a significant difference was found between the sham and EMR-only groups (p < 0.05), and Bcl-2, Bax, caspase-3 and -8 expressions increased in the EMR-only group. The level of Bcl-2, Bax, tumour necrosis factor-alpha (TNF-α), caspase-3 and -8 were compared and a significant difference was found between the sham and EMR+L-carnitine groups (p < 0.05) and Bcl-2, Bax, TNF-α, caspase-3 and -8 expressions increased in the EMR+L-carnitine group. The level of Bcl-2, Bax, TNF-α, caspase-3 and -8 were compared and a significant difference was found between the sham and EMR+Se groups (p < 0.05) and Bcl-2, Bax, TNF-α, caspase-3 and -8 expressions increased in the EMR+Se group. When the expression of caspase-8 was compared, a significant difference was found between the EMR-only and EMR+Se groups (p < 0.05). Caspase-8 expression decreased in EMR+Se group compared with EMR-only group.

CONCLUSION

Electromagnetic radiation exposure resulted in testicular apoptosis in rats, mainly by the intrinsic pathways by down-regulated expression of caspase-8. Reduction in the activation of the intrinsic pathway of apoptosis was found higher with selenium administration compared with L-carnitine administration.

Selenium modulates β-cyfluthrin-induced liver oxidative toxicity in rats

This study was designed to investigate the possibility of β-cyfluthrin to induce oxidative stress and biochemical perturbations in rat liver and the role of selenium in alleviating its toxic effects. Male Wister rats were randomly divided into four groups of seven each, group I served as control, group II treated with selenium (200 µg/kg BW), group III received β-cyfluthrin (15 mg/kg BW, 1/25 LD50 ), and group IV treated with β-cyfluthrin plus selenium. Rats were orally administered their respective doses daily for 30 days. The administration of β-cyfluthrin caused elevation in lipid peroxidation (LPO) and reduction in the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR). A decrease in reduced glutathione (GSH) content was also observed. Liver aminotransferases (AST and ALT) and alkaline phosphatase (ALP) were decreased, whereas lactate dehydrogenase (LDH) was increased. Selenium in β-cyfluthrin-induced liver oxidative injury of the rats modulated LPO, CAT, SOD, GSH, GST, GPx, and GR. Also, liver AST, ALT, ALP, and LDH were maintained near normal level due to selenium treatment. It is concluded that selenium scavenges reactive oxygen species and render a protective effect against β-cyfluthrin toxicity.

Antioxidant effect of selenium on lipid peroxidation, hyperlipidemia and biochemical parameters in rats exposed to diazinon

Diazinon (DZN) is one of the most organophosphate insecticides that widely used in agriculture and industry. Selenium is generally recognized to be a trace mineral of great importance for human health, protecting the cells from the harmful effects of free radicals. Therefore, the present study was carried out to investigate the alterations in biochemical parameters, free radicals and enzyme activities induced by diazinon in male rat serum, and the role of selenium in alleviating the negative effects of DZN. Animals were divided into four groups of seven rats each; the first group was used as control. Groups 2, 3 and 4 were treated with selenium (Se; 200μg/kg BW), diazinon (DZN; 10mg/kg BW) and diazinon plus selenium, respectively. Rats were orally administered their respective doses daily for 30 days. Results obtained showed that DZN significantly induced thiobarbituric acid reactive substances (TBARS) and decreased the activities of glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) and the levels of reduced glutathione (GSH) in rat sera. Aminotransferases (AST, ALT), phosphatases (AlP, AcP) and lactate dehydrogenase (LDH) activities were significantly increased while acetylcholinesterase (AChE) activity was decreased due to DZN administration. Also, DZN treatment caused significant perturbations in lipids profile and serum biochemical parameters. On the other hand, Se alone significantly decreased the levels of TBARS, total lipids, cholesterol, urea and creatinine, while increased the activities of antioxidant enzymes and glutathione content, total protein (TP) and albumin. In addition, Se in combination with DZN partially or totally alleviated its toxic effects on the studied parameters. In conclusion, Se has beneficial effects and could be able to antagonize DZN toxicity.

Protection of cisplatin-induced spermatotoxicity, DNA damage and chromatin abnormality by selenium nano-particles

Cisplatin (CIS), an anticancer alkylating agent, induces DNA adducts and effectively cross links the DNA strands and so affects spermatozoa as a male reproductive toxicant. The present study investigated the cellular/biochemical mechanisms underlying possible protective effect of selenium nano-particles (Nano-Se) as an established strong antioxidant with more bioavailability and less toxicity, on reproductive toxicity of CIS by assessment of sperm characteristics, sperm DNA integrity, chromatin quality and spermatogenic disorders. To determine the role of oxidative stress (OS) in the pathogenesis of CIS gonadotoxicity, the level of lipid peroxidation (LPO), antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) and peroxynitrite (ONOO) as a marker of nitrosative stress (NS) and testosterone (T) concentration as a biomarker of testicular function were measured in the blood and testes. Thirty-two male Wistar rats were equally divided into four groups. A single IP dose of CIS (7 mg/kg) and protective dose of Nano-Se (2 mg/kg/day) were administered alone or in combination. The CIS-exposed rats showed a significant increase in testicular and serum LPO and ONOO level, along with a significant decrease in enzymatic antioxidants levels, diminished serum T concentration and abnormal histologic findings with impaired sperm quality associated with increased DNA damage and decreased chromatin quality. Coadministration of Nano-Se significantly improved the serum T, sperm quality, and spermatogenesis and reduced CIS-induced free radical toxic stress and spermatic DNA damage. In conclusion, the current study demonstrated that Nano-Se may be useful to prevent CIS-induced gonadotoxicity through its antioxidant potential.