Iron-induced injury of rat testis

Diquat causes mouse testis injury through inducing heme oxygenase-1-mediated ferroptosis in spermatogonia

Diquat dibromide (DQ) is a globally used herbicide in agriculture, and its overuse poses an important public health issue, including male reproductive toxicity in mammals. However, the effects and molecular mechanisms of DQ on testes are limited. In vivo experiments, mice were intraperitoneally injected with 8 or 10 mg/kg/ day of DQ for 28 days. It has been found that heme oxygenase-1 (HO-1) mediates DQ-induced ferroptosis in mouse spermatogonia, thereby damaging testicular development and spermatogenesis. Histopathologically, we found that DQ exposure caused seminiferous tubule disorders, reduced germ cells, and increased sperm malformation, in mice. Reactive oxygen species (ROS) staining of frozen section and transmission electron microscopy (TEM) displayed DQ promoted ROS generation and mitochondrial morphology alterations in mouse testes, suggesting that DQ treatment induced testicular oxidative stress. Subsequent RNA-sequencing further showed that DQ treatment might trigger ferroptosis pathway, attributed to disturbed glutathione metabolism and iron homeostasis in spermatogonia cells in vitro. Consistently, results of western blotting, measurements of MDA and ferrous iron, and ROS staining confirmed that DQ increased oxidative stress and lipid peroxidation, and accelerated ferrous iron accumulation both in vitro and in vivo. Moreover, inhibition of ferroptosis by deferoxamine (DFO) markedly ameliorated DQ-induced cell death and dysfunction. By RNA-sequencing, we found that the expression of HO-1 was significantly upregulated in DQ-treated spermatogonia, while ZnPP (a specific inhibitor of HO-1) blocked spermatogonia ferroptosis by balancing intracellular iron homeostasis. In mice, administration of the ferroptosis inhibitor ferrostatin-1 effectively restored the increase of HO-1 levels in the spermatogonia, prevented spermatogonia death, and alleviated the spermatogenesis disorders induced by DQ. Overall, these findings suggest that HO-1 mediates DQ-induced spermatogonia ferroptosis in mouse testes, and targeting HO-1 may be an effective protective strategy against male reproductive disorders induced by pesticides in agriculture.

Developmental exposure to cobalt chloride affected mouse testis via altered iron metabolism in adulthood

INRODUCTION

Cobalt (Co) is known to interfere with iron (Fe) metabolism that is essential for differentiating male germ cells. Our aim was to study the effect of developmental chronic cobalt exposure on mouse testis through changes in iron homeostasis in adulthood.

METHODS

Pregnant ICR mice were exposed to 75 mg (low dose) or 125 mg (high dose)/kg b.w. cobalt chloride (CoCl2) with drinking water for 3 days before delivery and treatment continued until postnatal day 90 of the pups. Age-matched control animals obtained regular tap water. Testes of control and Co-treated mice were processed for immunohistochemistry and inductively coupled plasma mass spectrometry. Sperm count was performed.

RESULTS

Chronic CoCl2 administration resulted in significant dose-dependent Co accumulation in sera and testes of the exposed mice. Fe content also showed a significant increase in sera and testes compared to the untreated controls. Surprisingly, testes of low dose-treated mice had ∼ 2.7-fold higher Fe content compared to those exposed to the high dose. A significant dose-dependent reduction in relative testis weight by 18.8% and by 37.7% was found after treatment with low and high dose CoCl2, respectively was found. Our study demonstrated that developmental chronic exposure to CoCl2 affected cellular composition of the testis manifested by germ cell loss and low sperm count, accompanied by altered androgen response in Sertoli cells (loss of stage-specific expression of androgen receptor). A possible mechanism involved is iron accumulation in the testis that was associated with altered ferroportin-hepcidin localization in seminiferous tubules depleted in germ cells. As a protective mechanism for germ cells in condition of iron excess, ferroportin was distributed in Sertoli cells around elongating spermatids. Similar changes in expression of transferrin receptor 1 (TfR1) and divalent metal transporter 1 (DMT1) implied that both factors of testicular Fe homeostasis are closely related. Outside the seminiferous tubules, Leydig cells localized ferroportin, hepcidin, DMT1 and TfR1 thus they could be considered as a main site for iron metabolism.

CONCLUSION

Our data suggest that Co exerts its effects on the testis by indirect mechanism possibly through alteration in Fe homeostasis.

Cadmium exposure during puberty damages testicular development and spermatogenesis via ferroptosis caused by intracellular iron overload and oxidative stress in mice

Cadmium (Cd) is a widespread environmental pollutant and a reproductive toxicant. It has been proved that Cd can reduce male fertility, however, the molecular mechanisms remain unveiled. This study aims to explore the effects and mechanisms of pubertal Cd exposure on testicular development and spermatogenesis. The results showed that Cd exposure during puberty could cause pathological damage to testes and reduce sperm counts in mice in adulthood. Moreover, Cd exposure during puberty reduced GSH content, induced iron overload and ROS production in testes, suggesting that Cd exposure during puberty may induce testicular ferroptosis. The results in vitro experiments further strengthened that Cd caused iron overload and oxidative stress, and decreased MMP in GC-1 spg cells. In addition, Cd disturbed intracellular iron homeostasis and peroxidation signal pathway based on transcriptomics analysis. Interestingly, these changes induced by Cd could be partially suppressed by pretreated with ferroptotic inhibitors, Ferrostatin-1 and Deferoxamine mesylate. In conclusion, the study demonstrated that Cd exposure during puberty maybe disrupted intracellular iron metabolism and peroxidation signal pathway, triggered ferroptosis in spermatogonia, and ultimately damaged testicular development and spermatogenesis in mice in adulthood.

Combined Protective Effects of Quercetin, Rutin, and Gallic Acid against Cadmium-Induced Testicular Damages in Young-Adult Rats

Cadmium (Cd) is a toxic metal that damages several tissues of animals and humans including the testis. The ameliorative effects of quercetin (QUE), rutin (RUT), and gallic acid (GAL) at 20 mg kg-1 body weight alone or in combination against testicular injury induced by Cd (24 mg kg-1 body weight) in male Wistar rats were evaluated in this study. Forty-two (42) rats were randomly grouped into six (6) groups: (1) vehicle control group, (2) Cd group, (3) RUT+Cd group, (4) GAL+Cd group, (5) QUE+Cd group, and (6) RUT+GAL+QUE+Cd group. At the end of the oral gavage of the tested chemicals, the rats were sacrificed, blood samples were collected, and testes were harvested and processed for biochemical assays. Cd exposure damaged the testis (smaller epithelium thickness and spermatogenesis index and sloughing of the epithelium); increased lipid peroxidation, glutathione S-transferase activity, and DNA fragmentation; and diminished glutathione reductase activity and serum testosterone level 40 days posttreatment. Treatment with the phenolics separately or in combination attenuated the effect of Cd on serum testosterone, glutathione reductase and glutathione S-transferase activities, lipid peroxidation, and percent fragmented DNA. The increased nitric oxide concentration in the QUE+Cd group was attenuated to control values in the combined (RUT+GAL+QUE+Cd) exposure group. Coadministration of the phenolics appears to have more substantial protective effects than their single effects against Cd-induced testicular DNA damage, glutathione S-transferase activity, and the recovery of testosterone levels and spermatogenesis index. Overall, the tested phenolics can reduce testicular damage more efficiently in their combined form than individual administration.

Effects of Ferroptosis on Male Reproduction

Ferroptosis is a relatively novel form of regulated cell death that was discovered in 2012. With the increasing research related to the mechanisms of ferroptosis, previous studies have demonstrated that the inactive of the intracellular antioxidant system and iron overload can result in the accumulation of reactive oxygen species (ROS), which can ultimately cause lipid peroxidation in the various cell types of the body. ROS accumulation can cause sperm damage by attacking the plasma membrane and damaging DNA. Acute ferroptosis causes oxidative damage to sperm DNA and testicular oxidative stress, thereby causing male reproductive dysfunction. This review aims to discuss the metabolic network of ferroptosis, summarize and analyze the relationship between male reproductive diseases caused by iron overload as well as lipid peroxidation, and provide a novel direction for the research and prevention of various male reproductive diseases.

In vitro effect of ferrous sulphate on bovine spermatozoa motility parameters, viability and Annexin V-labeled membrane changes

The aim of this study was to assess the dose- and time-dependent in vitro effects of ferrous sulphate (FeSO₄.7H₂O) on the motility parameters, viability, structural and functional activity of bovine spermatozoa. Spermatozoa motility parameters were determined after exposure to concentrations (3.90, 7.80, 15.60, 31.20, 62.50, 125, 250, 500 and 1000 μM) of FeSO₄.7H₂O using the SpermVision^TM CASA (Computer Assisted Semen Analyzer) system in different time periods. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay, and the Annexin V-Fluos was applied to detect the membrane integrity of spermatozoa. The initial spermatozoa motility showed increased average values at all experimental concentrations compared to the control group (culture medium without FeSO₄.7H₂O). After 2 h, FeSO₄.7H₂O stimulated the overall percentage of spermatozoa motility at the concentrations of ≤ 125 μM. However, experimental administration of 250 μM of FeSO₄.7H₂O significantly (P < 0.001) decreased the spermatozoa motility but had no negative effect on the cell viability (P < 0.05) (Time 2 h). The lowest viability was noted after the addition of ≥ 500 μM of FeSO₄.7H₂O (P < 0.001). The concentrations of ≤ 62.50 μM of FeSO₄.7H₂O markedly stimulated (P < 0.001) spermatozoa activity after 24 h of exposure, while at high concentrations of ≥ 500 μM of FeSO₄.7H₂O the overall percentage of spermatozoa motility was significantly inhibited (P < 0.001) and it elicited cytotoxic action. Fluorescence analysis confirmed that spermatozoa incubated with higher concentrations (≥ 500 μM) of FeSO₄.7H₂O displayed apoptotic changes, as detected in head membrane (acrosomal part) and mitochondrial portion of spermatozoa. Moreover, the highest concentration and the longest time of exposure (1000 μM of FeSO₄.7H₂O; Time 6 h) induced even necrotic alterations to spermatozoa. These results suggest that high concentrations of FeSO₄.7H₂O are able to induce toxic effects on the structure and function of spermatozoa, while low concentrations may have the positive effect on the fertilization potential of spermatozoa.

Copper oxychloride-induced testicular damage of adult albino rats and the possible role of curcumin in healing the damage

The current research study investigated the effect of 80 mg/kg b.wt./day curcumin (cur) against 50, 100, and 200 mg/kg copper oxychloride (COC) for 90 days induced testicular damage using histological, ultrastructural, and biochemical techniques. Histological and cellular abnormalities have been noted in seminiferous tubules of COC-treated group and treated group with Cur- and COC-treated group. The biochemical result showed that serum testosterone was significantly decreased in COC-treated rats and Cur COC-treated rats compared with the control groups. Testes copper content and malondialdehyde was increased, whereas the testes total antioxidant, manganese, ferrous, and zinc levels were decreased (p ≥ 0.05) compared to the control groups. In conclusion, the present work reported that the treatment of rats with 80 mg/kg body weight curcumin prior to treatment with COC did not mitigate the deleterious effects of COC and manifested no signs of protection.

Effect of Fe and Cd Co-Exposure on Testicular Steroid Metabolism, Morphometry, and Spermatogenesis in Mice

The mechanism of testicular toxicity of simultaneous multiple exposures to metals is poorly understood. Previous studies reported that the toxic effect of cadmium (Cd) is modified by tissue concentration of iron (Fe). Using the mice (Mus musculus) model in the present study, we demonstrated that combined Cd (25 mg kg^-1 bw) and Fe (100 mg kg^-1 bw) treatment increased both Cd and Fe testicular concentrations much more than separate exposures to either of the metals. Intratesticular Cd and Fe concentrations were inversely correlated (r = - 0.731, p < 0.05) on administration of Fe but not on combined exposure to both metals when they were positively correlated (versus Cd; r = 0.793, versus Fe; r = 0.779, p < 0.05). Additionally, Cd + Fe treatment increased testicular lipid peroxidation and depleted intratestesticular testosterone, cholesterol and glutathione concentrations much more than their separate treatment. This was also associated with decreased activity of the germ cell marker, testicular lactate dehydrogenase, and increased testicular myeloperoxidase activity. These changes resulted in decreased seminiferous epithelial height, tubular diameter, germ cell (spermatogonia, spermatocytes, and spermatids) numbers, and severe tissue damage. In conclusion, Cd + Fe intake have synergistic toxic effects on testicular steroid formation and spermatogenesis due to the high testicular concentrations of both metals.

Impact of elemental iron on human spermatozoa and mouse embryonic development in a defined synthetic culture medium

There is a paucity of studies on effect of iron in embryo culture procedures. This study aims to ascertain the optimal, tolerance and toxic levels of iron in a protein-free embryo culture medium (PFM) to determine the effect of iron on embryonic development. The application of PFM in assisted reproductive technologies (ART) is intended to eliminate disease transmission and improve ART treatment outcome. The optimal, tolerance and toxic levels of iron on human spermatozoa and mouse embryos were determined by challenging them with different levels of iron (ferric iron; Fe⁺³). Human normozoospermic semen samples (n=24) and days 1-4 Quakenbush Special (Qs) mouse embryos (n=1160) were incubated in PFM supplemented with different concentrations of Fe⁺³ over different periods of time. 2.0μg/mL (35.8μM) of Fe⁺³ was the optimal level of Fe⁺³ for human spermatozoa with a tolerance range of 0.5-2μg/mL; whereas a level of 0.11μg/mL (2μM) of Fe⁺³ was the optimum for day 2 embryos. Levels of ferric iron at 0.11 to 2.8μg/mL appear to enhance spermatozoa motility, preserve its DNA integrity and possibly increase percentage of blastocysts developed but levels of ferric iron >16μg/mL is hazardous for both spermatozoa and embryos. In spite of beneficial effects of iron it is premature to recommend its supplementation in embryo culture media because of the known deleterious nature of iron and the paucity of toxicological data. Toxicological studies must be performed following which it can be decided whether it is safe to consider iron as a supplement in human embryo and spermatozoa culture media.

Vitamin E Protection from Testicular Damage Caused by Intraperitoneal Aluminium

Different forms of Aluminium (Al) are environmental xenobiotics that induce free radical–mediated cytotoxicity and reproductive toxicity. Vitamin E ( α-tocopherol) is an antioxidative agent that has been reported to be important for detoxification pathways. This study was thus aimed at elucidating the protective effects of vitamin E towards aluminium toxicity on the histology of the rat testis. Al (5 mg/kg body weight) was administered intraperitoneally in 2 ml saline, either alone or immediately before vitamin E (500 mg/kg body weight), at a different point of abdomen, and the alterations in the testis tissue were analyaed histologically. Seven treated animals were sacrificed for each group, with the testes removed and examined histologically. In the Al-treated group, the germinal epithelium of the seminiferous tubules was thinner in places and spermatids were almost absent; sperm numbers were low and there were no sperm in the lumen. In the Al plus vitamin E rats, there were large numbers of spermatids and sperm in the seminiferous tubule lumen. In the vitamin E alone group, a normal histology was seen. Electron microscopically, in the Al-treated group there were irregularities in the nuclear membrane, some damaged mitochondria, a decrease in the number of ribosomes, and an increase in the number of lysosomes in the sertoli cell cytoplasm. In the primary spermatocyte cytoplasm, there was an increase in the rough endoplasmic reticulum. In the Al plus vitamin E group, the spermatogeneic cells and the sertoli cell cytoplasm showed an almost normal appearance. The ultrastructure of the testis in the vitamin E alone group showed a normal appearance. In conclusion, vitamin E antagonizes the toxic effects of Al at the histological level, thus potentially contributing to an amelioration of the testis histology in the Al-treated rats. The associated biochemical parameters merit further investigation.

Dose- and Time-Dependent In Vitro Effects of Divalent and Trivalent Iron on the Activity of Bovine Spermatozoa

This in vitro study was designed to assess the impact of divalent (Fe(2+)) or trivalent (Fe(3+)) iron on the activity and oxidative balance of bovine spermatozoa at specific time intervals (0, 2, 8, 16, and 24 h) during an in vitro culture. Forty-five semen samples were collected from adult breeding bulls and diluted in physiological saline solution supplemented with different concentrations (0, 1, 5, 10, 50, 100, 200, 500, 1000 μmol/L) of FeCl2 or FeCl3. Spermatozoa motion parameters were assessed using the SpermVision™ computer-aided sperm analysis (CASA) system. Cell viability was examined with the metabolic activity 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the nitroblue-tetrazolium (NBT) test was applied to quantify the intracellular superoxide formation. Both divalent and trivalent iron exhibited a dose- and time-dependent impact on the spermatozoa physiology and oxidative balance. Concentrations ≥50 μmol/L FeCl2 and ≥100 μmol/L FeCl3 led to a significant decrease of spermatozoa motility (P < 0.05) and mitochondrial activity (P < 0.001 with respect to 200-1000 μmol/L FeCl2/FeCl3; P < 0.01 in case of 100 μmol/L FeCl2/FeCl3), accompanied by a significant superoxide overproduction (P < 0.001 in terms of 200-1000 μmol/L FeCl2 and 500-1000 μmol/L FeCl3; P < 0.01 with respect to 100 μmol/L FeCl2 and 100-200 μmol/L FeCl3). On the other hand, concentrations below 10 μmol/L FeCl2 and 50 μmol/L FeCl3 proved to stimulate the spermatozoa activity, as shown by a significant preservation of the motility and viability characteristics (P < 0.001 in case of the motility parameters; P < 0.01 with respect to the spermatozoa viability), alongside a significant decline of the superoxide generation (P < 0.05). In a direct comparison, divalent iron has been shown to be more toxic than trivalent iron. Results from this in vitro study show that high concentrations of both forms of iron are toxic, while their low concentrations may have spermatozoa activity-promoting properties. In vitro concentrations of divalent or trivalent iron that could be regarded as critical are 50 μmol/L FeCl2 and 100 μmol/L FeCl3 when iron ceases to be an essential micronutrient in order to become a toxic risk factor.

Iron and copper in male reproduction: a double-edged sword

Iron and copper are essential trace nutrients playing important roles in general health and fertility. However, both elements are highly toxic when accumulating in large quantities. Their direct or indirect impact on the structure and function of male gonads and gametes is not completely understood yet. Excess or deficiency of either element may lead to defective spermatogenesis, reduced libido, and oxidative damage to the testicular tissue and spermatozoa, ultimately leading to fertility impairment. This review will detail the complex information currently available on the dual roles iron and copper play in male reproduction.

An association study of HFE gene mutation with idiopathic male infertility in the Chinese Han population

Mutations in the haemochromatosis gene (HFE) influence iron status in the general population of Northern Europe, and excess iron is associated with the impairment of spermatogenesis. The aim of this study is to investigate the association between three mutations (C282Y, H63D and S65C) in the HFE gene with idiopathic male infertility in the Chinese Han population. Two groups of Chinese men were recruited: 444 infertile men (including 169 with idiopathic azoospermia) and 423 controls with proven fertility. The HFE gene was detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The experimental results demonstrated that no C282Y or S65C mutations were detected. Idiopathic male infertility was not significantly associated with heterozygous H63D mutation (odds ratio=0.801, 95% confidence interval=0.452-1.421, χ(2)=0.577, P=0.448). The H63D mutation frequency did not correlate significantly with the serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone (T) levels in infertile men (P=0.896, P=0.404 and P=0.05, respectively). Our data suggest that the HFE H63D mutation is not associated with idiopathic male reproductive dysfunction.

Une nouvelle fonction pour la transferrine exprimée par le testicule

Chez l’homme, les oligospermies sévères sont associées à un faible taux de transferrine dans le liquide séminal. La transferrine apparaît comme un bon indicateur pour définir les dysfonctionnements testiculaires. Son niveau d’expression dans le testicule doit être parfaitement contrôlé. Elle y joue un rôl dans le transport du fer. Mais de récents résultats montrent l’existence d’une forme dimérique de la transferrine sertolienne comme puissant régulateur de la phagocytose des corps résiduels par les cellules de Sertoli.

The inhibitory effects of polychlorinated biphenyl Aroclor 1254 on Leydig cell LH receptors, steroidogenic enzymes and antioxidant enzymes in adult rats

Polychlorinated biphenyls (PCBs) are global pollutants of major concern to human and animal reproductive health. The present study has examined the impact of Aroclor 1254 exposure on oxidative stress and testicular Leydig cell function. Adult albino male rats of the Wistar strain were dosed for 30 days with daily intraperitoneal injections of 2 mg/kg Aroclor 1254 or vehicle (corn oil). One day after the last treatment, animals were euthanized and blood collected for the assay of serum testosterone and estradiol. Testes were removed and Leydig cells were isolated for the assay of luteinizing hormone (LH) receptors, steroidogenic enzymes cytochrome P450 side chain cleavage enzyme (P450 scc), 3beta-hydroxysteroid dehydrogenase (3beta-HSD) and 17beta-hydroxysteroid dehydrogenase (17beta-HSD). Cellular antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), and glutathione-S-transferase (GST) were also assayed. Lipid peroxidation (LPO) and reactive oxygen species (ROS) were quantified. Results showed that Aroclor 1254 exposure lowered serum testosterone and estradiol levels. Leydig cell LH receptor density, activities of the steroidogenic enzymes P450 scc, 3beta-HSD, 17beta-HSD, antioxidant enzymes SOD, CAT, GPX, GR, and GST were significantly diminished whereas, LPO and ROS significantly elevated. Taken together, these results suggest that inefficient LH receptors, steroidogenic enzymes and antioxidant enzymes are possible mechanisms by which Aroclor 1254 treatment disrupts Leydig cell steroidogenesis.

Spermatogenesis recovery in the mouse after iron injury

Alloys used as prosthetic devices for bone/joint replacement include some heavy metals such as chromium, iron, nickel, or titanium. Unfortunately, due to the aggressive nature of the physiological environment, corrosion of these alloys promotes the release of metal ions into the surrounding tissues causing systemic toxic effects. Our previous preliminary studies have demonstrated that iron induced several morphological changes within mice seminiferous epithelium. The aim of the present work was to investigate, over a one-month period, the possibility of recovery of mice seminiferous epithelium, previously damaged by iron. Male Charles River mice were dosed subcutaneously with 0.5 mL of an iron suspension of 538 mg/L +/- 10(-10) mg/L (n = 5) every 72 hours during two weeks, followed by a recovery period of 30 days. Fragments of the seminiferous tubules were fixed in glutaraldehyde and prepared for light and transmission electron microscopy. Regeneration of spermatogenesis was noted after a one-month period, as illustrated by the presence of normal germ cells, in the usual position within the seminiferous tubules. These germinal elements and the Sertoli cells have shown normal cytological features. These results strongly suggest that the deleterious effects induced by iron are reversible. The presence of residual bodies within Sertoli cells cytoplasm indicates that they are able to perform a normal functional activity in a recovered spermatogenesis.

Relationships of testicular iron and ferritin concentrations with testicular weight and sperm production in boars

The inverse relationship of testicular size and circulating follicle-stimulating hormone (FSH) concentrations has been documented, and accompanying this relationship is the change in color of the parenchymal tissue of the testes. Large testes (300 to 400 g) are pink to light red and small testes (100 g) are dark maroon with color gradations for weights in between. It was hypothesized that this color most likely represented an iron protein. Chromatographic analysis of testicular tissue indicated that the Fe was associated primarily with ferritin, and immunohistochemistry showed that Leydig cells were the primary location of ferritin storage within the testes. Concentrations of Fe and ferritin were higher in small testes and decreased as testes weight increased (P < 0.05). As testicular Fe concentrations increased, daily sperm production (DSP) and total DSP declined (P < 0.05). Genotyping six generations of Meishan x White composite boars (n = 288) for a quantitative trait locus that is indicative of elevated FSH and small testes in boars indicated that the Meishan genotype had elevated testicular iron concentrations and darker color in conjunction with reduced total DSP (P < 0.01). It is not thought the elevated iron concentrations affect testicular weights but are probably a result of elevated FSH and FSH inducement of Fe transport. The storage of Fe in Leydig cells may provide a reservoir of Fe for easy access by Sertoli and germ cells, but still provide a degree of protection to germ cells from ionic iron.

2-Bromopropane induces DNA damage, impairs functional antioxidant cellular defenses, and enhances the lipid peroxidation process in primary cultures of rat Leydig cells

Utilization of highly enriched preparations of steroidogenic Leydig cells has proven invaluable for studying the direct effects of various hormones and agents on Leydig cell function in vitro. It is widely reported that male reproductive organs are particularly susceptible to the deleterious effects of reactive oxygen species (ROS) and lipid peroxidation, which ultimately lead to impaired fertility. The purpose of the study was to examine the potential of 2-bromopropane (2-BP) to induce oxidative stress and antioxidant function in primary cultures of rat Leydig cells. Leydig cells were isolated from the testes of Sprague-Dawley rats. The purity of Leydig cells was determined to be 94.6% and the cells maintained their testosterone secreting capabilities for 48 h. Fresh medium containing 2-BP (1.00, 0.10, 0.01 mM, and vehicle control) and 1 U human chorionic gonadotropin (hCG) were added in the cell culture. Superoxide dismutase (SOD) activity, malondialdehyde (MDA), and glutathione peroxidase (GSH-PX) were analyzed in the medium of each well by biochemical methods. Additionally, DNA damage was examined using the Comet assay. The proportion of cells with undamaged DNA was decreased significantly and those with different grades of damaged DNA were increased significantly in the cells exposed to 2-BP. The level of MDA and GSH-PX activity increased significantly in the cell groups exposed to 0.10 and 1.00 mM 2-BP, whereas, SOD activity decreased considerably in these two groups of cells when compared to the control. The data indicate that 2-BP induces DNA damage, impairs functional antioxidant cellular defenses, and enhances the lipid peroxidation in cultured Leydig cells. These effects may be responsible for the testicular toxicity noted in laboratory animals and humans.