DNA Damage In Testicular Cells Research Articles

Quercetin Supplementation Alleviates Cadmium Induced Genotoxicity-Mediated Apoptosis in Caprine Testicular Cells.

Being a common environmental pollutant, cadmium causes detrimental health effects, including testicular injury. Herein, we document the ameliorative potential of quercetin, a potent antioxidant, against cadmium-induced geno-cytotoxicity and steroidogenic toxicity in goat testicular tissue. Cadmium induced different comet types (Type 0 - Type 4), indicating the varying degree of DNA-damage in testicular cells. The quantitative analysis at 50 and 100 µM cadmium concentration revealed the DNA damage with per cent tail DNA as 75.78 ± 1.49 and 94.65 ± 0.95, respectively, in comparison to the control group (8.87 ± 0.48) post 8h exposure duration. Cadmium caused a substantial decrease in the activity of key steroidogenic enzymes' (3β-HSD and 17β-HSD) along with reduction of testosterone level in testicular tissue. Furthermore, cadmium treatment induced various types of deformities in sperm, altered the Bax/Bcl-2 expression ratio in testicular tissue and thus suggesting the apoptosis-mediated death of testicular cells. Simultaneous quercetin supplementation, however, significantly (p < 0.05) averted the aforementioned cadmium-mediated damage in testicular tissue. Conclusively, the cadmium-induced DNA-damage and decrease in steroidogenic potential results in death of testicular cells via apoptosis, which was significantly counteracted by quercetin co-supplementation, and thus preventing the cadmium-mediated cytotoxicity of testicular cells.

High doses of clethodim-based herbicide GrassOut Max poses reproductive hazard by affecting male reproductive function and early embryogenesis in Swiss albino mice

Clethodim is a widely used and approved class II herbicide, with little information about its impact on the reproductive system. Herein, we investigated the male reproductive toxicity of clethodim using a mouse model. GrassOut Max (26% clethodim-equivalent) or analytical grade clethodim (≥90%) were given orally to male mice for 10 d in varying doses. All parameters were assessed at 35 d post-treatment. Significant decrease in testicular weight, decreased germ cell population, elevated DNA damage in testicular cells and lower serum testosterone level was observed post clethodim based herbicide exposure. Epididymal spermatozoa were characterized with significant decrease in motility, elevated DNA damage, abnormal morphology, chromatin immaturity and, decreased acetylated-lysine of sperm proteins. In the testicular cells of clethodim-based herbicide treated mice, the expression of Erβ and Gper was significantly higher. Proteomic analysis revealed lower metabolic activity, poor sperm-oocyte binding potential and defective mitochondrial electron transport in spermatozoa of clethodim-based herbicide treated mice. Further, fertilizing ability of spermatozoa was compromised and resulted in defective preimplantation embryo development. Together, our data suggest that clethodim exposure risks male reproductive function and early embryogenesis in Swiss albino mice via endocrine disrupting function.

Testicular dysfunction induced by aluminum oxide nanoparticle administration in albino rats and the possible protective role of the pumpkin seed oil

BackgroundEven though the widespread of nanoalumina and their benefits in all fields, its potential impacts on male reproductive system have limited information.ObjectiveThe present study was conducted to investigate the testicular dysfunction of nanoalumina and the protective role of pumpkin seed oil (PSO) against potential adverse impacts induced by alumina nanoparticles (Al2O3-NPs) in male rat.MethodologyAl2O3-NPs were administered to the rat orally at a dose of 70 mg/kg body weight once a day for 28 successive days, while pumpkin seed oil was administered to the rat orally at 4 mL/kg b w before administration of Al2O3-NPs, once a day for 28 successive days. After the administration period, sperm concentration, motility, morphology, and DNA damage, as biomarkers of reproductive toxic effects, were evaluated using sperm analysis and comet assays, and histopathological examination of testis was performed. In addition, level of the serum testosterone hormones were estimated, and the levels of oxidative stress biomarkers that take part in the reproductive pathologies such as catalase, glutathione, and malondialdehyde were estimated.ResultsThe present results revealed that Al2O3-NPs induced DNA damage in testicular cells, marked histopathological alterations, and caused a significant elevation in MDA in testicular tissue. There was a significant decline in GSH and CAT activities. Furthermore, there was a significant decline in serum testosterone level in the testicular tissue of Al2O3-NP-administered rats. In contrast, pumpkin seed oil co-administration alleviated DNA damage and improved the histopathological alterations in the testicular tissues. Moreover, pumpkin seed oil co-administration significantly reduced MDA and improved the antioxidant defenses in testicular tissue.ConclusionThe current study concluded that Al2O3-NPs caused testicular dysfunction by generating oxidative injury. Otherwise, PSO co-administration successfully attenuated the adverse impacts of Al2O3-NPs via suppression of oxidative stress and apoptosis as well as enhancement of the antioxidant defense system.

Reproductive toxicity of perchlorate in rats

Perchlorate, as an oxidizer, has many applications such as explosives and pyrotechnics, especially in rocket propellants and missile motors. Because it was found in water including wells and drinking water in the US, its effect on human health was being noted. However, the reproductive toxic effect on perchlorate is still unclear. In present study, the effects of repeated exposure to perchlorate on reproductive toxicity were evaluated in Wistar rats. The rats were treated orally with perchlorate at doses of 0.05, 1.00 or 10.00 mg/kg body weight (b.w.) daily for 8 weeks. The levels of T3 and T4 hormones in the rat serum were detected by radioimmunoassay kit. The indexes of reproduction, percentage of organ in body weight (%) and frequency of abnormal sperm cells were also analyzed in this study. DNA damage in testicular cells was evaluated by Comet assay. The levels of MDA, GSH and SOD were examined in testicle tissues of rats by ELISA. The expression of c-fos and fas protein was examined in testicle tissues by immunohistochemistry. The results showed that perchlorate did not affect the body weight of rats. Perchlorate also significantly decreased indexes of live birth and weaning in the groups of 1.00 and 10.00 mg/kg, and viability index only in the 10.00 mg/kg group (P < 0.05). Perchlorate also significantly decreased the serum level of T3 in male rats of 1.00 and 10.00 mg/kg groups, increased the rate of sperm abnormality (10.00 mg/kg), potentially caused DNA damage in testicular cells and altered the status of oxidative stress in male rats. In addition, because of the increase in the expression of fas and c-fos protein in testicle tissues, perchlorate could induce apoptosis in spermatogenesis. Thus, these findings indicate that perchlorate could cause DNA damage in testicular tissues and reduce testicular spermatogenic ability, resulting in reproductive toxicity.

Resveratrol Restores Type 2 Diabetes‐induced Alterations in Transcriptional Regulation of DNA Damage Repair Pathway genes in Goto‐Kakizaki Rats

BackgroundType 2 diabetes (T2DM)‐ characterized by insulin resistance and hyperglycemia‐affects organ systems resulting in macrovascular and microvascular complications. T2DM also induces DNA damage in varieties of cells, including germ cells, which forms a basis for the increased incidence of cancers in diabetic patients. The present study investigated modulatory effects of Resveratrol on gene expressions of DNA damage repair pathway‐related proteins in non‐obese Goto‐Kakizaki (GK) T2DM rats.MethodsTwo groups of adult male GK rats (70‐day‐old), a T2DM group and a T2DM+R (DMR) group, along with an age‐ and sex‐matched Wistar rat control group were used. Resveratrol (20 mg/kg; po) was given once daily for 120 days. Body weight and blood glucose levels were measured once a week. The animals were killed on day 121 and testes were removed and processed for RNA extraction. The quantitative analysis of 84 DNA damage repair pathway genes was carried out using SABiosciences RT2 Profiler™ PCR Array. The gene expression (2−ΔΔct) was considered regulated when the expression showed a minimum of 2‐fold increase/decrease compared to that in controls, and the Student's t‐test detected statistical significance at P&lt;0.05 level.ResultsOf the 84 genes studied, only 25 (30%) genes were differentially regulated either in DM or DMR groups. Diabetes increased the expression of apoptosis‐related genes‐ Mbd4 (methyl‐CpG‐binding domain), Mgmt (O6‐methylguanine‐DNA methyltransferase) which Resveratrol recovered to control levels in DMR group (P&lt;0.05). Diabetes also increased the expression of cell cycle control genes‐ Hus1 (checkpoint protein) and Cdc25c (cell division cycle 25c) and decreased that of Cdkn1a (cyclin‐dependent kinase inhibitor 1a). Resveratrol treatment recovered the expression of only Cdc25c in DMR group. Diabetes increased the expression of base‐excision repair (BER) related genes‐ Apex1 (DNA lyase), Mpg (DNA‐methyladenine glycosylase), Parp1 ((poly(ADP‐ribose) polymerase)), and Parp2, and nucleotide excison repair (NER) genes‐Dclre1a (DNA cross‐link repair protein), Rnf (Ubiquitinase), Xpc (xeroderma pigmentation complementation), and double‐strand breaks repair (DSBR) genes‐ Prkdc (DNA‐dependent protein kinase), Rad51c (DNA repair protein), Rad52, Blm (Bloom syndrome), and Rpa1 (Replication protein), and other genes related to DNA damage repair‐ Wrn (Helicase), Poli (DNA polymerase iota), and Sirt1 (Sirtuin) (P&lt;0.05). Resveratrol recovered the expression of the genes mentioned earlier in DMR group, except that of Dclre1a, Rad52, Blm, Wrn, and Poli. In consensus with the gene expressions, diabetes increased DNA damage in testicular cells, and Resveratrol recovered the damage to the control level in DMR group.ConclusionsResveratrol decreases DNA damage due to which diabetes‐induced pro‐apoptotic and pro‐cell cycle arrest gene expressions recovered to control level. The increased DNA damage upregulates gene expressions related to BER, NER, and DSBR. Resveratrol‐mediated prevention/alleviation of DNA damage results in normalization of expressions of DNA damage repair pathway genes. (Supported by Kuwait University Grant#RM01/12 and SRUL02/13).Support or Funding InformationSupported by Kuwait University Grant#RM01/12 and SRUL02/13This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Potential reproductive health effects and oxidative stress associated with exposure to potassium dichromate (K2Cr2O7) and magnesium sulphate (MgSO4) in male mice.

To investigate the potential harmful effects of potassium dichromate and magnesium sulphate causing oxidative stress and reproductive toxicity in adult male mice model. The experimental work was conducted on sixty male mice (Mus musculus) divided into three groups. Mice in group B and C received potassium dichromate and magnesium sulphate of 5.0 and 500 mg/Kg body weight/ml respectively, for sixty days. The blood sample was analyzed to assess oxidative stress and cellular damage. RESULTS showed high malondialdehyde (MDA) and low levels of antioxidant enzymes [catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx)] in both potassium dichromate and magnesium sulphate administrated groups as compared to control group. Reduced number of sperm count and excessive destruction of testicular follicles, including destruction of spermatids, leydig cells and sertoli cells, were also seen in both groups. We concluded from present study that potassium dichromate and magnesium sulphate causes oxidative stress by generation of reactive oxygen species (ROS) and causing DNA damage in testicular cells leading to adverse reproductive abnormalities.

X-Ray Induced DNA Damage and Repair in Germ Cells of PARP1−/− Male Mice

Poly(ADP-ribose)polymerase-1 (PARP1) is a nuclear protein implicated in DNA repair, recombination, replication, and chromatin remodeling. The aim of this study was to evaluate possible differences between PARP1−/− and wild-type mice regarding induction and repair of DNA lesions in irradiated male germ cells. Comet assay was applied to detect DNA damage in testicular cells immediately, and two hours after 4 Gy X-ray irradiation. A similar level of spontaneous and radiation-induced DNA damage was observed in PARP1−/− and wild-type mice. Conversely, two hours after irradiation, a significant level of residual damage was observed in PARP1−/− cells only. This finding was particularly evident in round spermatids. To evaluate if PARP1 had also a role in the dynamics of H2AX phosphorylation in round spermatids, in which γ-H2AX foci had been shown to persist after completion of DNA repair, we carried out a parallel analysis of γ-H2AX foci at 0.5, 2, and 48 h after irradiation in wild-type and PARP1−/− mice. No evidence was obtained of an effect of PARP1 depletion on H2AX phosphorylation induction and removal. Our results suggest that, in round spermatids, under the tested experimental conditions, PARP1 has a role in radiation-induced DNA damage repair rather than in long-term chromatin modifications signaled by phosphorylated H2AX.

Therapeutic approaches of melatonin in microwave radiations-induced oxidative stress-mediated toxicity on male fertility pattern of Wistar rats

Microwave (MW) radiation produced by wireless telecommunications and a number of electrical devices used in household or in healthcare institutions may adversely affects the reproductive pattern. Present study aimed to investigate the protective effects of melatonin (is well known antioxidant that protects DNA, lipids and proteins from free radical damage) against oxidative stress-mediated testicular impairment due to long-term exposure of MWs. For this, 70-day-old male Wistar rats were divided into four groups (n = 6/group): Sham exposed, Melatonin (Mel) treated (2 mg/kg), 2.45 GHz MWs exposed and MWs + Mel treated. Exposure took place in Plexiglas cages for 2 h a day for 45 days where, power density (0.21 mW/cm2) and specific absorption rate (SAR 0.14 W/Kg) were estimated. After the completion of exposure period, rats were sacrificed and various stress related parameters, that is LDH-X (lactate dehydrogenase isoenzyme) activity, xanthine oxidase (XO), ROS (reactive oxygen species), protein carbonyl content, DNA damage and MDA (malondialdehyde) were performed. Result shows that melatonin prevent oxidative damage biochemically by significant increase (p < 0.001) in the levels of testicular LDH-X, decreased (p < 0.001) levels of MDA and ROS in testis (p < 0.01). Meanwhile, it reversed the effects of MWs on XO, protein carbonyl content, sperm count, testosterone level and DNA fragmentation in testicular cells. These results concluded that the melatonin has strong antioxidative potential against MW induced oxidative stress mediated DNA damage in testicular cells.

Investigation on the Genotoxic Effects of Long-Term Administration of Sodium Arsenite in Bone Marrow and Testicular Cells In Vivo Using the Comet Assay

The main source of environmental arsenic exposure in most populations is drinking water in which inorganic forms of arsenic predominate. The single-cell gel electrophoresis technique (the comet assay) measures DNA damage, including double-strand and single-strand breaks, in somatic cells after a variety of genotoxic insults. We have used this method to measure damage to cellular DNA in the bone marrow and testicular cells of mice using the alkaline comet assay for the former and neutral comet assay for the latter. Swiss albino male mice were exposed to sodium arsenite in drinking water at concentrations of 10, 50,100, and 200 mg/l for a period of three months. Concurrently, negative and positive control sets were maintained. The negative control animals were given distilled water as drinking water for the same period of treatment while the animals in positive control sets were either given single or multiple injections of EMS (100 mg/kg body weight) according to the tissue sampled. Following long-term exposure, there was a significant dose-dependent reduction in the size and weight of testes. The comet parameters of DNA, such as tail length (microm), % of DNA in tail, and Olive tail moment (arbitrary units) were increased in both bone marrow and testicular cells due to arsenic-induced DNA strand breaks. A positive dose response relationship was noted. The magnitude of DNA strand break was more pronounced in the bone marrow cells than in the testicular cells. The minimum effective concentrations for inducing DNA damage in bone marrow cells and testicular cells were 10 mg/l and 50 mg/l, respectively. The results of the study indicate that arsenic in drinking water is genotoxic in mice and the comet assay can be used for examining DNA damage in testicular cells as a parameter for evaluating male reproductive toxicity.

Influence of oxygen on radiation-induced DNA damage in testicular cells of C3H mice

Radiation-induced DNA single-strand break (ssb) induction and rejoining were measured in murine testicular cells using the alkaline comet assay. Individual cells in different stages of differentiation were identified on the basis of DNA content. As expected, induction of DNA ssb in testis cells irradiated on ice was independent of ploidy, and the extent of damage was similar to that produced in cells from other normal tissues. However, in vivo irradiation of air-breathing mice produced more ssb in haploid than tetraploid germ cells, although their rates of rejoining were similar and comparable to repair rates of cells from other normal tissues. In addition, irradiation of testis in situ produced only half as much damage as irradiation in vitro, and this could be explained only in part by the rapid ssb rejoining occurring during irradiation and cell isolation. A lower cellular oxygenation was postulated to account for the apparent resistance of testis cells to induction of breaks and the difference in induction in relation to DNA content. This was confirmed when carbogen inhalation and treatment with nicotinamide not only increased the overall degree of ssb induction in all these cells, but also reduced differences between cells of different ploidies. Results using the hypoxic cell cytotoxin RSU 1069 confirmed that the extent of hypoxia was not as severe in the testis as in the SCCVII murine tumour. It can be concluded from these data that the oxygenation of all testis cells is low enough to confer radioresistance, and that haploid testis cells are less hypoxic than tetraploid spermatocytes.

DNA damage in testicular cells in vitro: The response of rat and human cells to known testicular toxicants

DNA damage in testicular cells in vitro: The response of rat and human cells to known testicular toxicants