Cadmium exposure and its association with oxidative stress, MT1A methylation, and idiopathic male infertility in Egypt: A case-control study

Idiopathic male infertility, a significant health concern, lacks a clear etiology. Cadmium (Cd), a widespread environmental pollutant known to impact male reproductive health negatively, can accumulate in mussels, a common food source in Egypt. This study investigated the link between ecological Cd exposure, oxidative stress, MT1A methylation, and idiopathic male infertility in two regions of Alexandria. Thirty-three infertile men and 33 fertile controls were included. Cd levels were measured in mussels from the study sites and in participants' blood and semen. Biomarkers reflecting Cd exposure and its effects were assessed. Mussel Cd levels exceeded regulatory limits. Infertile men revealed significantly higher blood and semen Cd levels, reduced semen quality, increased oxidative stress, and elevated MT1A methylation compared to controls. MT1A methylation was inversely correlated with sperm count and is the strongest predictor of idiopathic male infertility, demonstrating the lowest p-value and considerable effect size. This study suggests that environmental Cd exposure, potentially through mussel consumption, may contribute to idiopathic male infertility in Egypt by increasing oxidative stress, inducing epigenetic modifications, and impairing semen quality. These findings underscore the need for further research into the mechanisms underlying Cd-induced male infertility and the development of preventative strategies.

Positive association of ethylene oxide levels with young stroke: a population-based study

Background

Ethylene oxide (EtO), a highly reactive organic compound with extensive industrial applications, poses significant health risks. The association between EtO exposure and stroke was not well established. This study examined the association between EtO exposure and stroke among US adults using data from the 2013-2018 National Health and Nutrition Examination Survey (NHANES).

Methods

We used appropriately weighted multifactorial logistic regression models to analyze the data and validated the findings with smoothed curve fitting. Stratified analysis and interaction assessments were performed to evaluate the robustness of the findings.

Results

The study included 5,071 participants, balanced between men and women, with a stroke prevalence of 4.1%. Higher EtO levels were associated with rising rates of stroke (OR = 1.23, 95% CI: 1.06-1.42). Individuals in the top 25% group displayed a stroke prevalence 1.6 times higher than those in the bottom 25% group (OR = 1.60, 95%CI: 1.03-2.48). Stratified analysis demonstrated a significant positive association between EtO and stroke in individuals under 50 years (OR = 1.94, 95%CI: 1.38-2.72), while no significant association was found in those aged 50 and above (OR = 0.97, 95%CI: 0.83-1.14).

Conclusion

This study identified a significant association between EtO exposure and stroke occurrence in young adults in the United States.

Association between ethylene oxide levels and depressive symptoms: A cross-sectional study based on NHANES 2013-2018 database

BACKGROUND AND AIM

Ethylene oxide (EO) is a commonly used compound with known health risks. However, the specific association between EO exposure and the development of depressive symptoms has not been well established. Therefore, this study aimed to examine the potential association between EO exposure, as indicated by hemoglobin adduct of ethylene oxide (HbEO) levels, and the occurrence of depressive symptoms.

METHODS

We employed logistic regression, restricted cubic spline, and subgroup analysis to investigate the association between EO exposure and the occurrence of depressive symptoms. Additionally, we conducted a mediating effect analysis to explore the potential factors influencing the association between EO exposure and depressive symptoms.

RESULTS

Elevated HbEO levels were associated with the development of depressive symptoms. After adjusting for potential confounders, the highest quartile of HbEO levels showed an odds ratio (OR) of 3.37 [95 % confidence interval (CI): 1.87-6.10, P = 0.002] compared with the lowest quartile. Additionally, a linear association was observed between HbEO levels and the risk of depressive symptoms. We also revealed that the levels of several inflammatory factors and triglycerides mediated the association between EO exposure and the occurrence of depressive symptoms.

CONCLUSIONS

Higher levels of EO exposure were related to an increased risk of developing depressive symptoms. The analysis also suggested that the inflammatory response might play a mediating role in the pathway from EO exposure to depressive symptoms.

Association between ethylene oxide exposure and periodontitis: a cross-sectional study from NHANES 2013-2014

BACKGROUND

Exposure to ethylene oxide (EO) induces inflammation and oxidative stress, which are the main mechanisms of periodontitis. However, the effect of EO on periodontal health is not unclear. In this study, we aimed to explore the relationship between EO exposure and the risk of periodontitis in general US adults.

METHODS

Data used in our study from the National Health and Nutritional Examination Survey (NHANES) 2013-2014. The EO biomarker, hemoglobin adduct of EO (HbEO), was measured in blood samples utilizing high-performance liquid chromatography-tandem mass spectrometry. Periodontitis category was defined by the CDC/AAP according to clinical periodontal parameters. Natural cubic spline, weight multivariable logistic regression analyses and subgroup analysis were used to explore the association between EO exposure and the risk of periodontitis.

RESULTS

A total of 1497 participants over the age of 30 were included in our study. A non-linear positive association with periodontitis was identified for HbEO levels. Participants in the highest tertile of HbEO levels were more likely to have poorer periodontal health compared to the lowest tertile (ORtertile3vs1 = 2.80, 95% CI: 1.85-4.24). Similar results were also found in different subgroups.

CONCLUSIONS

HbEO levels are positively associated with poor periodontal health in US adults. Additional longitudinal studies are necessary to further enhance our comprehension of the impact of exposure to EO on periodontal status.

Associations of ethylene oxide exposure and "Life's Essential 8"

Ethylene oxide (EtO) is a widely used industrial chemical with recognized health risks. While its carcinogenic properties have been extensively studied, emerging evidence suggests potential associations with cardiovascular diseases. Using the recently introduced Life's Essential 8 (LE8) score as a comprehensive cardiovascular health (CVH) measure, this study aimed to elucidate the relationship between EtO exposure and CVH. Data from the National Health and Nutrition Examination Survey (NHANES) encompassing 3748 adults was analyzed. CVH was assessed using the LE8 score, which incorporates diet, physical activity, tobacco/nicotine exposure, sleep duration, BMI, non-HDL cholesterol, blood glucose, and blood pressure. The association between EtO exposure, gauged by Hemoglobin adduct (HbEtO) levels, and CVH was examined using linear regression and Cox regression models. An inverse relationship between EtO exposure and the overall CVH score was identified. Specifically, for every 1-unit increase in ln-transformed HbEtO, a 3.69-point decrease in the total CVH score was observed. An inverted J-shaped association between ln-transformed HbEtO and CVH score emerged, with an inflection point at 3.15 pmol/g Hb. Elevated EtO exposure was not significantly linked to all-cause mortality but was robustly associated with increased cardiovascular mortality. Elevated EtO exposure is negatively associated with CVH, as outlined by the LE8 metrics. Beyond a certain threshold, this association underscores the cardiovascular risks of EtO exposure and highlights the importance of further research to determine underlying mechanisms and recommend preventive strategies.

Association between blood ethylene oxide levels and the prevalence of hypertension

The relationship of blood ethylene oxide levels with hypertension and blood pressure has not been addressed. A total of 5005 participants from the National Health and Nutrition Examination Survey (NHANES) 2013-2016 were enrolled. Hypertension was defined as a mean systolic blood pressure (SBP) of at least 140 mmHg, a mean diastolic blood pressure (DBP) of at least 90 mmHg, or both, and/or the self-reported use of prescription drugs for diagnosed hypertension. Generalized linear regression models and restricted cubic spline plots were performed to explore the associations of ethylene oxide levels with hypertension and blood pressure. The prevalence of hypertension in the study sample was 27.6%. After adjusting for confounding factors, compared with the lowest quantile, the odds ratios (ORs) with 95% confidence intervals (CIs) of hypertension across the quantiles of ethylene oxide levels were 0.80 (0.63, 1.03), 0.91 (0.71, 1.16), and 1.39 (1.06, 1.82), respectively (P-value for trend = 0.001). Compared with the lowest quantile, the highest quantile of blood ethylene oxide levels was significantly associated with the worst DBP profile by approximately 2.67 mmHg. Blood ethylene oxide levels showed a strong nonlinear and positive association with DBP, while no significant association was observed between blood ethylene oxide levels and SBP. These results provide epidemiological evidence of elevated blood levels of ethylene oxide in relation to a higher prevalence of hypertension and higher DBP. Further study is warranted to address these issues.

Effect of syringic acid on steroid and gonadotropic hormones, hematological indices, sperm characteristics and morphologies, and markers of tissue damage in methyl cellosolve-administered rats

Methyl cellosolve (MTC) is an established gonadotoxic and hematotoxic compound that is commonly and universally utilized in herbicide, liquid soap, stain, dye, paint, and brake fluid manufacturing industries as a solvent. Due to its wide range usage, this study therefore investigated the effect of syringic acid (SYAC) on hematological indices, sperm characteristics and morphologies, and markers of tissue damage in MTC administered male Wistar rats. Thirty (30) rats divided into six groups were used. Rats in group 1 served as control, those in group 2 were administered MTC for 30 consecutive days, those in groups 3, 4, and 5 were treated with 25, 50, and 75 mg/kg body weight of SYAC respectively also for 30 consecutive days immediately after each day MTC administrations, while rats in group 6 received 75 mg/kg body weight of SYAC only throughout. Compared with control, administrations of MTC resulted in a significant decrease in spermatozoa count, number of normal and live spermatozoa, Hb count, MCH, MCHC, serum TC, and LH, while number of abnormal spermatozoa, RBC and WBC counts, activities of serum AST, ALT, GGT, LDH, and ADH were significantly increased. Treatments with 25 mg/kg of SYAC significantly reduced the RBC and WBC counts, serum activities of AST, ALT, GGT, and increased TC concentration. Treatments with 50 mg/kg SYAC significantly lowered the number of abnormal spermatozoa, RBC count, activities of serum ALT, AST, LDH, ADH, and increased the number of normal spermatozoa, MCV, MCH, and MCHC, while 75 mg/kg of SYAC significantly decreased the serum activities of AST, ALT, GGT, LDH, ADH, and increased serum TC concentration. Findings from this study have revealed the hepatoprotective effect of SYAC at all doses investigated but did not confer spermatoprotection and hematoprotection against MTC-induced toxicities, and looking at the 3 doses investigated, 50 mg/kg of SYAC yielded the best effect.

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MTC significantly decreased live sperm, sperm count, MCH, MCHC, and Hb counts.

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MTC significantly increased number of abnormal sperm, RBC and WBC counts.

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MTC significantly increased serum activities of AST, ALT, GGT, LDH, and ADH.

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SYAC significantly decreased RBC and WBC counts, AST, ALT, GGT, LDH, and ADH.

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SYAC significantly increased number of normal sperm, MCV, MCH, and MCHC counts.

Phytochemical analysis and protective effects of Vaccinium macrocarpon (cranberry) in rats (Rattus norvegicus) following ethylene oxide-induced oxidative insult

The Vaccinium genus comprises more than 126 genera of perennial flowering plants that are commonly adapted to poor and acidic soils or epiphytic environments. Their molecular and genomic characterization is a result of the recent advent in next-generation sequencing technology. In the current research, extracts were prepared in different media, such as petroleum ether, methanol and ethanol. An extract of Vaccinium macrocarpon (cranberry) was used at a dose of 200–400 mg/kg by weight (B.wt). Levels of oxidative stress markers, i.e., superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), advanced oxidation protein products (AOPPs) and malondialdehyde (MDA), were measured. A histopathological study of six vital organs in rats was also conducted. The results indicated that the antioxidant levels were lower in the group given only ethylene oxide (EtO) but higher in the groups receiving cranberry extract as a treatment. Major improvements were also observed in stress markers such as advanced oxidation protein products (AOPPs) and MDA following cranberry treatment. Histopathological changes induced by EtO were observed in the heart, kidney, liver, lung, stomach and testis and were reversed following cranberry treatment. The major toxic effects of EtO were oxidative stress and organ degeneration, as observed from various stress markers and histopathological changes. Our study showed that this extract contains strong antioxidant properties, which may contribute to the amelioration of the observed toxic effects.

Ethylene glycol butyl ether deteriorates oocyte quality via impairing mitochondrial function

Ethylene glycol butyl ether (EGBE) is a ubiquitous environmental pollutant that is commonly used in maquillage, industrial, and household products. EGBE has been shown to cause blood toxicity, carcinogenicity, and organ malformations. However, little is known about the impact of EGBE on the female reproductive system, especially oocyte quality. Here, we reported that EGBE influenced oocyte quality by showing the disturbed oocyte meiotic capacity, fertilization potential, and early embryonic development competency. Specifically, EGBE exposure impaired spindle/chromosome structure, microtubule stability, and actin polymerization to result in the oocyte maturation arrest and aneuploidy. In addition, EGBE exposure compromised the dynamics of cortical granules and their component ovastacin, leading to the failure of sperm binding and fertilization. Last, single-cell transcriptome analysis revealed that EGBE-induced oocyte deterioration was caused by mitochondrial dysfunction, which led to the accumulation of ROS and occurrence of apoptosis. Altogether, our study illustrates that mitochondrial dysfunction and redox perturbation is the major cause of the poor quality of oocytes exposed to EGBE.

Nicotinamide Mononucleotide Restores the Meiotic Competency of Porcine Oocytes Exposed to Ethylene Glycol Butyl Ether

Ethylene glycol butyl ether (EGBE), a type of glycol ethers, is a common chemical used in both industrial and household products. Increasing animal studies have indicated that it produces reproductive problems, such as testicular damage, reduced female fertility, death of embryos, and birth defects. However, how it influences the female germ cells has not yet determined. Here, we found that EGBE exposure resulted in the defective porcine oocyte maturation via disruption of cytoskeleton dynamics, showing the abnormal spindle assembly, chromosome alignment, and actin organization. Meanwhile, EGBE exposure perturbed the mitochondrial distribution and function, leading to the accumulation of reactive oxygen species (ROS) and generation of DNA damage and apoptosis. Of note, nicotinamide mononucleotide (NMN) supplementation rescued the meiotic defects caused by EGBE exposure via restoring NAD⁺ level and mitochondrial function and thus eliminating the excessive ROS. Taken together, our observations illustrate that NMN supplementation is an effective strategy to protect oocyte quality against environmental pollutant-induced deterioration, contributing to improve the animal and human fertility.

Hepatic oxidative stress, up-regulation of pro-inflammatory cytokines, apoptotic and oncogenic markers following 2-methoxyethanol administrations in rats

2-methoxyethanol (2-ME) is an organic solvent widely used in the manufacture of brake fluids, paints, resins, varnish, nail polish, acetate cellulose, wood coloring, and as a plasticizer in plastics manufacturing. We therefore, investigated its effect on the liver, in a time-course study in male Wistar rats. Animals were orally administered 50 mg/kg body weight of 2-ME for a period of 7, 14, and 21 days. Following 7 days of administration of 2-ME, there was a significant increase in the level of Bax, c-Myc, K-Ras, TNF-α, IL-1β, IL-6, MDA and GPx activity, while the levels of Bcl-2, NO and GSH were significantly reduced compared with control. At the end of 14 days exposure, Bcl-2, and GSH levels, as well as GST activity, were significantly decreased, while levels of Bax, c-Myc, K-Ras, caspase-3, TNF-α, IL-1β, IL-6, MDA and NO were significantly increased compared with control. After 21 days of 2-ME administration, Bcl-2, IL-10, and GSH levels, as well as SOD and GST activities, were significantly decreased, while levels of Bax, c-Myc, K-Ras, caspase-3, p53, TNF-α, IL-1β, IL-6, MDA and NO were significantly increased compared with control. Lastly, liver histopathology confirmed and corroborated the biochemical findings reported above. We therefore, advised that exposures to 2-ME should be strictly avoided as it could trigger hepatic damage through the disorganization of the antioxidant system, up-regulation of inflammatory, apoptotic, and oncogenic markers in rats.

Ethylene glycol monomethyl ether-induced testicular oxidative stress and time-dependent up-regulation of apoptotic, pro-inflammatory, and oncogenic markers in rats

Ethylene glycol monomethyl ether (EGME) is a major component of paints, lacquers, inks, and automobile brake fluids. As a result, exposures to humans are inevitable. We therefore, investigated in this study, its effect on testicular cells in a time-course manner in male Wistar rats. Animals were orally administered 50 mg/kg body weight of EGME for duration of 7, 14, and 21 days. Following 7 days of the administration, levels of NO and GSH were significantly reduced, while levels of c-Myc, K-Ras, caspase-3, IL-6, TNF-α, and IL-1β were significantly increased compared with control. At the end of 14 days exposure, GPx, and SOD activities, as well as IL-10 level were significantly decreased, while levels of c-Myc, K-Ras, p53, Bax, caspase-3, IL-6, TNF-α, IL-1β, and GST activity were significantly elevated compared with control. After 21 days of EGME administration, Bcl-2, IL-10, and NO levels were significantly decreased, while levels of c-Myc, K-Ras, p53, Bax, caspase-3, IL-6, TNF-α, IL-1β, MDA and GST activity were significantly increased compared with control. After 7, 14, and 21 days of EGME administrations, testis histopathology showed severe loss of seminiferous tubules, the seminiferous epithelium revealed very few spermatocytes, spermatids, spermatogonia, spermatozoa, and Sertoli cells, while the interstitial tissue is eroded, with scanty abnormal Leydig cells, compared with the control that appeared normal. We therefore, concluded that EGME-induced testicular toxicity as a result of EGME administration could be via the disorganization of the endogenous antioxidant systems as well as up-regulation of pro-inflammatory, apoptotic and oncogenic mediators in rats.

Value and limitation of structure-based profilers to characterize developmental and reproductive toxicity potential

The uncertainty regarding the safety of chemicals leaching from food packaging triggers attention. In silico models provide solutions for screening of these chemicals, since many are toxicologically uncharacterized. For hazard assessment, information on developmental and reproductive toxicity (DART) is needed. The possibility to apply in silico toxicology to identify and quantify DART alerts was investigated. Open-source models and profilers were applied to 195 packaging chemicals and analogues. An approach based on DART and estrogen receptor (ER) binding profilers and molecular docking was able to identify all except for one chemical with documented DART properties. Twenty percent of the chemicals in the database known to be negative in experimental studies were classified as positive. The scheme was then applied to 121 untested chemicals. Alerts were identified for sixteen of them, five being packaging substances, the others structural analogues. Read-across was then developed to translate alerts into quantitative toxicological values. They can be used to calculate margins of exposure (MoE), the size of which reflects safety concern. The application of this approach appears valuable for hazard characterization of toxicologically untested packaging migrants. It is an alternative to the use of default uncertainty factor (UF) applied to animal chronic toxicity value to handle absence of DART data in hazard characterization.

The signal transduction of xanthone as a protector on 2-methoxyethanol-induced cardiac cell damage in mice

This research aims at investigating the role of antioxidant of xanthone on 2-methoxyethanol (2-ME)-induced cardiac cell damage in mice. Forty mice were grouped into: (1) The control group (mice were given with distilled water), (2) the ME group (mice were given with 2-ME 200 mg/kg BW orally), and (3) the treatment group (mice were given of xanthone with doses 60 mg, 120 mg, 240 mg/kg BW orally and were also given 2-ME 200 mg/kg BW). Their blood samples were taken to measure the level of lactate dehydrogenase (LDH) and creatinine kinase-MB (CK-MB). Heart tissues were also taken to determine the malondialdehyde (MDA), histological findings of heart damage, and the immunohistochemical of the expression of superoxide dismutase (SOD) and glutathione peroxidase (GPx). The administration of 2-ME resulted in a significant increase level of the LDH, CK-MB, MDA, and a decrease in SOD and GPx expression were compared with the control group. The 2-ME also induced loss of the normal structure of heart cells and necrosis. However, treatment with the xanthone, only dose 240 mg/kg BW significantly decrease the level of LDH, CK-MB, MDA, and increase SOD, GPx expression. The xanthone 240 mg/kg BW also demonstrated significantly improved heart cell damage. From the results, it is concluded that the xanthone are a potent antioxidant in against 2-ME-induced cardiac toxicity in mice, through increasing SOD and GPx expression, and also inhibiting LDH, CK-MB and MDA.

Chronic Exposure to Water of Lake Qaroun Induced Metal-Related Testicular Damage and Endocrine Disruption in Male Fish

The uncontrolled releasing of hazardous wastes into Lake Qaroun was adversely impacting the aquatic environment and its biota. Therefore, this approach was designed to investigate the impact of these discharges on the reproductive and testicular function of Oreochromis niloticus. Several biomarkers were applied on the testicular tissues as metal bioaccumulation levels, histological examination with recording the ovotestis appearance and antioxidant status after 45 days of exposure to 0, 10, 20, & 30% of Lake Qaroun water (LQW). The bioaccumulated Cu, Mn, Fe, Pb, and Cd were unequally distributed in the testes but all these metals showed a significant concentration-dependent elevation among the studied groups. The exposure to LQW significantly increased the histological alterations in the testicular tissues as vacuolar degeneration, loss of tubular organization, and degeneration of Leydig cell. Based on the frequent appearance of histopathological abnormalities and ovotestis recording, the most deformed testicular tissues were observed in the 30% LQW-exposed groups. The ovotestis severity index (OSI) was significantly raised in LQW-exposed groups compared to the control group. The activities of superoxide dismutase, catalase as well as glutathione-reduced levels were significantly (p < 0.05) decreased in testes after chronic exposure to LQW. On the other pole, the activities of glutathione peroxidase enzyme and malondialdehyde formation were sharply increased. In view of the above, the exposure to LQW induced metal-related oxidative damage to the testicular tissues and impaired the male reproductive health. This study showed strong correlations between the anthropogenic activities around Lake Qaroun and the reproductive dysfunction in fish.

Reproductive effects of cadmium on sperm function and early embryonic development in vitro

Cadmium is a major environmental toxicant that is released into the atmosphere, water and soil in the form of cadmium oxide, cadmium chloride, or cadmium sulfide via industrial activities, such as the manufacturing of batteries and pigments, metal smelting and refining and municipal waste incineration. In the present study, we investigated the effects of cadmium exposure on sperm quality parameters, fertilization capacity and early embryonic development. Our study showed that in vitro incubation of human or mouse sperms with cadmium for a long time (up to 24 hours) could significantly decreased sperm motility in a concentration- and time-dependent manner. Exposure to cadmium in the environment for a short term (30 min) did not affect sperm motility but significantly reduced in vitro fertilization rate. We also evaluated the effects of cadmium at concentrations of 0.625 μg/ml, and 1.25 μg/ml on early embryonic development in vitro and observed that the blastocyst formation rate dramatically decreased with increasing cadmium concentration. This finding emphasizes the hazardous effects of cadmium on sperm quality as well as on natural embryo development and raises greater concerns regarding cadmium pollution.

Participation of protein kinases in cytotoxic and proapoptotic effects of ethylene glycol ethers and their metabolites in SH-SY5Y cells

Ethylene glycol ethers (EGEs) are compounds widely used in many branches of industry. Their toxicological profile in the peripheral tissues is relatively well described, but little is known about their action on the central nervous system (CNS). In this study, we evaluated the effect of 2-ethoxyethanol (EE), 2-butoxyethanol (BE), 2-phenoxyethanol (PHE) and their metabolites on necrotic (estimated by cell viability and lactate dehydrogenase release) and apoptotic (caspase-3 activity and mitochondrial membrane potential) processes and reactive oxygen species' (ROS) production in human neuroblastoma (SH-SY5Y) cells. We have shown that, similar to the peripheral tissues, EGE metabolites in most of the performed assays revealed greater potential to damage than the parent compounds in the CNS cells. Subsequently, we investigated the participation of some selected protein kinases in the degenerative activity of PHE and its main metabolite, phenoxyacetic acid (PHA). It has been found that a GSK3β inhibitor weakened the damaging effects of PHE and PHA in each of the performed assays. Furthermore, the kinases, p38-MAPK, JNK-MAPK and PKC, had a significant role in the cytotoxic and proapoptotic effects of PHA. These results indicate that the neurotoxic effect of EGEs may stem from their impact on many intracellular signal transduction pathways.

Responses of testis, epididymis, and sperm of pubertal rats exposed to functionalized multiwalled carbon nanotubes

The present study investigated the response of testes, epididymides and sperm in pubertal Wistar rats following exposure to 0, 0.25, 0.5, 0.75, and 1.0 mg kg(-1) functionalized multi-walled carbon nanotubes (f-MWCNTs) for 5 days. The results showed that administration of (f-MWCNTs) significantly increased the activities of superoxide dismutase, catalase, and glutathione peroxidase in a dose-dependent manner in both testes and sperm compared with control group. Moreover, the significant decrease in the activity of glutathione-S-transferase and glutathione level was accompanied with significant elevation in the levels of hydrogen peroxide and malondialdehyde in both testes and sperm of (f-MWCNTs)-treated rats. The spermiogram of (f-MWCNTs)-treated rats indicated significant decrease in epididymal sperm number, sperm progressive motility, testicular sperm number and daily sperm production with elevated sperm abnormalities when compared with the control. Exposure to (f-MWCNTs) decreased plasma testosterone level and produced marked morphological changes including decreased geminal epithelium, edema, congestion, reduced spermatogenic cells and focal areas of tubular degeneration in the testes. The lumen of the epididymides contained reduced sperm cells and there was mild to severe hyperplasia epithelial cells lining the duct of the epididymis. Collectively, pubertal exposure of male rats to (f-MWCNTs) elicited oxidative stress response resulting in marked testicular and epididymides dysfunction.

6-Gingerol-Rich Fraction from Zingiber officinale Prevents Hematotoxicity and Oxidative Damage in Kidney and Liver of Rats Exposed to Carbendazim

Ginger (Zingiber officinale) is a globally marketed flavoring agent and cooking spice with a long history of human health benefits. The fungicide carbendazim (CBZ) is often detected in fruits and vegetables for human nutrition and has been reported to elicit toxic effects in different experimental animal models. The present study investigated the protective effects of 6-Gingerol-rich fraction (6-GRF) from ginger on hematotoxicity and hepatorenal damage in rats exposed to CBZ. CBZ was administered at a dose of 50 mg/kg alone or simultaneously administered with 6-GRF at 50, 100, and 200 mg/kg, whereas control rats received corn oil alone at 2 mL/kg for 14 days. Hematological examination showed that CBZ-mediated toxicity to the total white blood cell (WBC), neutrophils, lymphocytes, and platelets counts were normalized to the control values in rats cotreated with 6-GRF. Moreover, administration of CBZ significantly decreased the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase as well as glutathione level in the livers and kidneys of rats compared with control. However, the levels of hydrogen peroxide (H2O2) and malondialdehyde were markedly elevated in kidneys and livers of CBZ-treated rats compared with control. The significant elevation in the plasma indices of renal and hepatic dysfunction in CBZ-treated rats was confirmed by light microscopy. Coadministration of 6-GRF exhibited chemoprotection against CBZ-mediated hematotoxicity, augmented antioxidant status, and prevented oxidative damage in the kidney and liver of rats.

Comparative assessment of onion and garlic extracts on endogenous hepatic and renal antioxidant status in rat

BACKGROUND

Despite growing claims of functional health benefits in folkloric medicine, the safety of chronic/elevated intakes of onion and garlic cannot be assumed. Therefore, this study assesses oral administration of varied doses of onion and garlic on some biomarkers of hepatic and renal functions in rats.

METHODS

Animals were divided into five groups: control group received vehicle and extract-treated groups received varied doses of onion or garlic extract (0.5 mL and 1.0 mL/100 g bwt/day) for 6 weeks.

RESULTS

Both doses of onion caused marked (p<0.05) increase in hepatic and renal levels of glutathione (GSH), glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) and marked (p<0.05) decrease in malondialdehyde (MDA). Treatment with low dose of garlic elicited similar trend except in hepatic CAT, renal SOD and GST levels. A high dose of garlic only caused marked (p<0.05) increase in hepatic GST, renal GST, and SOD. Both doses of onion and low dose of garlic significantly (p<0.05) enhanced renal Na+/K+-ATPase activity. Only a high dose of onion caused significant (p<0.05) increase in hepatic aspartate transaminase (AST), alkaline phosphatase (ALP), and decrease in plasma AST activities.

CONCLUSIONS

These findings suggest antioxidant enhancing capability for both doses of onion and low dose of garlic, while high dose of garlic elicited pro-oxidant conditions.

Garcinia kola seed ameliorates renal, hepatic, and testicular oxidative damage in streptozotocin-induced diabetic rats

CONTEXT

In Africa, Garcinia kola Heckel (Guttiferae) seed is commonly recommended in folklore medicine for the treatment of diabetes and its associated complications.

OBJECTIVE

The present study evaluated this traditional claim by mechanistic investigation into the effect of G. kola seed administration on renal, hepatic, and testicular oxidative damage in streptozotocin (STZ)-induced diabetic rats.

MATERIALS AND METHODS

Diabetes mellitus was induced in adult male Wistar rats by an intraperitoneal injection of STZ (50 mg/kg). The diabetic rats were thereafter treated orally once per day with G. kola seed (250 mg/kg) and monitored for 14 d. Clinical observations, plasma biochemistry, hormonal profile, oxidative stress indices, sperm characteristics, and histopathological examination of the kidney, liver, and testes were evaluated to monitor treatment-related effects of G. kola seed in STZ-induced diabetic rats.

RESULTS AND DISCUSSION

Garcinia kola seed administration significantly ameliorated hyperglycemia mediated damage by decreasing the blood glucose level (72.8% and 84.6% on the 7th and 14th post-treatment days, respectively), enhancement of the antioxidant system, inhibition of lipid peroxidation, and improving the architecture of the kidney, liver, and testes in STZ-induced diabetic rats. In addition, G. kola seed intervention restored the kidney and liver function biomarkers, the sperm characteristics as well as the plasma levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, triiodothyronine (T3), and thyroxine (T4) to normal in STZ-induced diabetic rats.

CONCLUSION

The findings from this investigation provide persuasive scientific support for the traditional use of G. kola seed in the treatment of diabetes and its associated complications.

Triclosan exhibits a tendency to accumulate in the epididymis and shows sperm toxicity in male Sprague-Dawley rats

Triclosan (TCS) is considered a potent endocrine disruptor that causes reproductive toxicity in non-mammals, but it is still unclear exactly whether TCS has adverse effects on the sperm or reproductive organs in mammals. In this study, we aimed to evaluate the distribution status of TCS in male reproductive organs of rats, and seek the correlation with the TCS-induced sperm toxicity or reproductive organ damage. Male rats were intragastrically administered with TCS at a dose of 50 mg/kg, the kinetics of TCS in the plasma and reproductive organs were investigated. TCS in testes and prostates both showed a lower-level distribution compared to that in the plasma, which indicates it has no tendency to accumulate in those organs. However, TCS in the epididymides showed a longer elimination half-life (t1/2 z), a longer the mean retention time (MRT), and a lower clearance (CLZ /F) compared with those in the plasma. Besides, the ratios of mean area under the concentration-time curve (AUC)(0-96 h(epididymides/plasma)) and AUC(0-∞(epididymides/plasma)) were 1.13 and 1.51, respectively. These kinetic parameters suggest TCS has an accumulation tendency in the epididymides. Based on this, we investigated the TCS-induced sperm toxicity and histopathological changes of reproductive organs in rats. TCS was given intragastrically at doses of 10, 50, and 200 mg/kg for 8 weeks. Rats treated with the high dose (200 mg/kg) of TCS showed a significant decrease in daily sperm production (DSP), changes in sperm morphology and epididymal histopathology. Considering the histopathological change in the epididymides, TCS may induce the epididymal damage due to the epididymal accumulation of that.

Impairment of hepatic and renal functions by 2,5-hexanedione is accompanied by oxidative stress in rats

2,5-Hexanedione (2,5-HD) is the toxic metabolite of n-hexane which is widely used as solvent in numerous industries. The present study elucidated the precise mechanism of 2,5-HD in hepatorenal toxicity by determining the involvement of oxidative stress in rats. Adult male Wistar rats were exposed to 0, 0.25, 0.5, and 1% 2,5-HD in drinking water for 21 days. Exposure to 2,5-HD caused liver and kidney atrophy evidenced by significant elevation in serum aminotransferases, alkaline phosphatase, albumin, bilirubin, urea, creatinine, and electrolytes levels compared with control. The marked dose-dependent increase in total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL) was accompanied with significant decrease in high-density lipoprotein (HDL) levels in 2,5-HD-exposed animals when compared with the control. Administration of 2,5-HD significantly diminished glutathione (GSH) level but increased the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), and glutathione-S-transferase (GST) concomitantly with marked elevation in hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels in liver and kidney of the treated groups compared with control. These findings suggest that undue exposure to 2,5-HD at environmentally relevant levels may impair liver and kidney functions through induction of oxidative stress.

Testicular effect of a mixture of 2-methoxyethanol and 2-ethoxyethanol in rats

BACKGROUND

2-Methoxyethanol (ME) and 2-ethoxyethanol (EE) represent a large group of chemicals which are used separately or as mixtures. These compounds exert multidirectional toxic effects. The present studies aimed to demonstrate the effects of ME and EE alone and their mixture on the reproductive organs in the rats.

METHODS

Male Wistar rats were treated subcutaneously with ME and EE alone (1.25-5.0mM/kg/day) or with their mixture (1:1) for 4 weeks. After completion of the experiment, the testes, epididymides, and prostate were weighed. In post-mitochondrial supernatant of the testes, the level of total protein, non-protein and protein sulfhydryl groups, malondialdehyde, total antioxidant status, and glutathione peroxidase and glutathione reductase activities were determined.

RESULTS

Exposure to ME alone resulted in a dose-dependent decrease in the organ weights, the total protein, non-protein and protein sulfhydryl groups. EE alone led to less marked alterations. Co-exposure to ME and EE caused alterations similar as in the rats treated with ME alone.

CONCLUSIONS

Marked testicular atrophy, decrease in epididymis and prostate weights are predominant effects of the repeated exposure to relatively low doses of ME and EE. A decrease in the total protein level, and protein sulfhydryl groups may be responsible for testicular atrophy. A significant depletion of non-protein sulfhydryl groups and occasionally elevated glutathione peroxidase activity may indicate that ME and EE resulted in disturbances of pro-oxidant/antioxidant balance. The study suggests that testicular toxicity in male rats co-exposed to ME and EE is mainly caused by the former compound.

Modulatory role of kolaviron in phenytoin-induced hepatic and testicular dysfunctions in Wistar rats

Phenytoin, an anticonvulsant agent used for the treatment of epilepsy has been reported to exhibit toxic side effects on the liver and testes. The present study investigated the protective effects of kolaviron (KV, a bioflavonoid from Garcinia kola seeds) against hepatic and testicular damage in rats exposed to phenytoin. The study consisted of four groups of six rats per group. Group I rats received 2 mL/kg of corn alone while group II received 75 mg/kg of phenytoin (PHT) alone. Groups III and IV were co-treated with kolaviron (200 mg/kg KV) and vitamin E (500 mg/kg VTE), respectively, for 14 days. The antioxidant status, hepatic and reproductive functional parameters were subsequently determined. PHT treatment significantly (p < 0.05) increased superoxide dismutase (SOD) and catalase (CAT) activities, elevated lipid peroxidation (LPO) and hydrogen peroxide (H2O2) levels along with significant reduction in the hepatic and testicular levels of glutathione (GSH). Moreover, PHT exposure elicited significant increases in alkaline phosphatase (ALP) and aspartate aminotransferase (AST) levels. The significant reduction in seminal epithelium thickness and the diameter of seminiferous tubules was accompanied with marked decrease in sperm motility, sperm count, and viability in PHT-treated rats. However, antioxidant status and the functional indices of liver and testes were restored to near control levels in rats co-treated with KV and VTE. In conclusion, KV and VTE protect the liver and testes against functional impairment due to PHT treatment.

Ethylene glycol ethers induce oxidative stress in the rat brain

Ethylene glycol ethers (EGEs) are components of many industrial and household products. Their hemolytic and gonadotoxic effects are relatively well known while their potential adverse effects on the central nervous system have not yet been clearly demonstrated. The aim of the present study was to examine the effects of 4-week administration of 2-buthoxyethanol (BE), 2-phenoxyethanol (PHE) and 2-ethoxyethanol (EE) on the total antioxidant capacity, activity of some antioxidant enzymes, such as the superoxide dismutase (SOD), catalase, glutathione peroxidase (GPX) and glutathione reductase and lipid peroxidation in the frontal cortex and hippocampus in the rat. These studies showed that BE and PHE decreased the total antioxidant activity, SOD and GPX activity, while increased lipid peroxidation in the frontal cortex. Like in the frontal cortex, also in the hippocampus BE and PHE attenuated the total antioxidant activity, however, lipid peroxidation was increased only in animals which received BE while reduction in GPX activity was present in rats administered PHE. The obtained data indicated that 4-week administration of BE and PHE, but not EE, reduced the total antioxidant activity and enhanced lipid peroxidation in the brain. In the frontal cortex, adverse effects of PHE and BE on lipid peroxidation probably depended on reduction in SOD and GPX activity, however, in the hippocampus the changes in the total antioxidant activity and lipid peroxidation were not connected with reduction of the investigated antioxidant enzyme activity.

Kolaviron prevents carbendazim-induced steroidogenic dysfunction and apoptosis in testes of rats

The study evaluated the protective role of kolaviron (an isolated biflavonoid from the seed of Garcinia kola) and vitamin E in carbendazim-induced reproductive dysfunction in male rats. Adult male Wistar rats were orally exposed to carbendazim (200mg/kg) singly or in combination with kolaviron (100 and 200mg/kg). Exposure to carbendazim significantly decreased the activities of superoxide dismutase and catalase but markedly increased sialic acid concentration and lipid peroxidation in the testes of rats. Western blot analysis revealed that carbendazim treatment decreased the expression of steroid acute regulatory (StAR) protein and androgen binding protein (ABP) with concomitant decrease in activities of steroidogenic enzymes. Germ cell apoptosis in carbendazim-treated rats was confirmed by TUNEL assay. However, pretreatment with kolaviron and vitamin E restored the testicular antioxidant status and steroidogenesis and decreased apoptotic nuclei to near control level in carbendazim-treated rats. Kolaviron may prove useful in combating carbendazim-induced reproductive toxicity.

Hepatic, testicular and spermatozoa antioxidant status in rats chronically treated with Garcinia kolaseed

ETHNOPHARMACOLOGICAL RELEVANCE

Garcinia kola seed is commonly used in African Traditional Medicine as a remedy for liver disorders, hepatitis, bronchitis, throat infections as well as an aphrodisiac and fertility enhancing substance. Owing to the abundance of complex mixture of phenolic compounds in Garcinia kola seed, there is a growing safety concern on its long-term use in folklore medicine. The present study evaluated the hepatic, testicular and spermatozoa antioxidant status in rats chronically treated with Garcinia kolaseed.

MATERIALS AND METHODS

Adult male Wistar rats were randomly assigned to four groups of 10 rats each and were orally administered with Garcinia kola at 0, 250, 500 and 1000mg/kg for 6consecutive weeks. Clinical observations, serum biochemistry, oxidative stress biomarkers, spermatozoa parameters and histopathological examination of the organs were assessed to monitor treatment-related adverse effects inrats.

RESULTS

Long-term treatment of Garcinia kola had no adverse effect on the spermatozoa characteristics but significantly elevated testosterone concentration when compared to the control group. Improvement of antioxidant systems was accompanied by a significant decrease in malondialdehyde level in the liver, testes and spermatozoa of Garcinia kola-treated rats. Histological observation revealed that chronic administration of Garcinia kola had no effect on the liver and testes at all doses when compared with control.

CONCLUSION

Garcinia kola seed boosts the antioxidant status and exhibits no adverse effect on the liver, testes and spermatozoa after a long-term oral exposure inrats.

Influence of kolaviron and vitamin E on ethylene glycol monoethyl ether-induced haematotoxicity and renal apoptosis in rats

The present study investigated the protective effects of kolaviron, a biflavonoid from the seed of Garcinia kola, and vitamin E on ethylene glycol monoethyl ether (EGEE)-induced haematotoxicity and renal apoptosis in male rats. EGEE was administered at a dose of 200 mg kg(-1) alone or simultaneously administered with kolaviron (100 and 200 mgkg(-1) ) and vitamin E (50 mg kg(-1) ) for 14 days. Results of haematological examination showed that white blood cells, platelets, neutrophils and mean corpuscular haemoglobin concentration were significantly lower, whereas lymphocytes were increased in EGEE-exposed rats compared with those in the control. Administration of EGEE caused a significant decrease in the superoxide dismutase and catalase activities as well as in the glutathione level but significantly increased glutathione Stransferase activity and levels of hydrogen peroxide and lipid peroxidation in kidneys of rats compared with those in the control. Also, EGEE-treated rats showed significant elevation in the serum urea and creatinine with marked increase in the frequency of terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay-positive apoptotic cells in the tubular epithelial cells in comparison with the control. Co-administration with kolaviron or vitamin E exhibited chemoprotective effects against EGEE-mediated haematotoxicity, augmented renal antioxidant status and prevented the induction of renal apoptosis.

Neurotoxicity of Nigerian bonny light crude oil in rats

Biometal accumulation may contribute to organ toxicity in individuals using the Nigerian bonny light crude oil (BLCO) for ailment management. We assessed the levels of biometals, antioxidant status, along with histomorphometric analysis to investigate the effect of BLCO, commonly use in folklore medicine, on the brain. Adult male Wistar rats were dosed by gavage with BLCO at 0, 200, and 800 mg/kg(-1) of BLCO for 7 days. Results showed the accumulation of iron, zinc, nickel and lead, in contrast to copper, in BLCO-treated rats. Administration of BLCO disrupted the brain's antioxidant system and significantly increased levels of hydrogen peroxide and lipid peroxidation. Although the Purkinje layer and maximum width of Purkinje cells were not affected, BLCO treatment significantly decreased molecular layer, granular layer, and density of Purkinje cells of the cerebellum. The neurotoxicity of BLCO may be the result of oxidative stress resulting from loss of biometal homeostasis as well as toxicant injury from other constituents of BLCO.

Chemoprotection of ethylene glycol monoethyl ether-induced reproductive toxicity in male rats by kolaviron, isolated biflavonoid from Garcinia kola seed

The present study investigated the protective effect of kolaviron, a biflavonoid from the seed of Garcinia kola, on ethylene glycol monoethyl ether (EGEE)-induced reproductive toxicity in male rats. The protective effect of kolaviron was validated using vitamin E, a standard antioxidant. EGEE was administered at a dose of 200 mg/kg. Other groups of rats were simultaneously treated with kolaviron (100 and 200 mg/kg) and vitamin E (50 mg/kg) for 14 days. EGEE treatment resulted in significant decrease in glutathione (GSH) level, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities but markedly increased the glutathione-S-transferase (GST) and lactate dehydrogenase (LDH) activities in the testes. In the spermatozoa, administration of EGEE caused significant decrease in the activities of CAT, GPx, GST and LDH as well as in the level of GSH but significantly increased SOD activity with concomitant increase in hydrogen peroxide and malondialdehyde levels in both testes and spermatozoa. EGEE-exposed rats showed marked testicular degeneration with concomitant decrease in spermatozoa quantity and quality. Overall, EGEE causes reproductive dysfunction in rats by altering antioxidant systems in the testes and spermatozoa. Kolaviron or vitamin E exhibited protective effects against EGEE-induced male reproductive toxicity by enhancement of antioxidant status and improvement in spermatozoa quantity and quality.

Effects of ethylene glycol ethers on cell viability in the human neuroblastoma SH-SY5Y cell line

Ethylene glycol ethers (EGEs) are a class of chemicals used extensively in the manufacture of a wide range of domestic and industrial products, which may result in human exposure and toxicity. Hematologic and reproductive toxicity of EGEs are well known whereas their action on neuronal cell viability has not been studied so far. In the present study, we investigated the effects of some EGEs on cell viability and on the hydrogen peroxide-induced damage in the human neuroblastoma (SH-SY5Y) cells. It has been found that 2-phenoxyethanol in a concentration-dependent manner (5-25 mM, 24 h) increased the basal and H(2)O(2)-induced lactate dehydrogenase (LDH) release and 3-[4,5-dimethylthiazol-2-yl]2,5-diphenyl tetrazolium bromide (MTT) reduction. 2-Butoxyethanol given alone did not affect LDH release and MTT reduction but concentration-dependently enhanced the cytotoxic effect of H(2)O(2). 2-Isopropoxyethanol significantly and concentration-dependently (1-25 mM) increased the basal LDH release and attenuated MTT reduction, but did not potentiate the cytotoxic effect of H(2)O(2). Contrary to this, 2-methoxyethanol did not show a cytotoxic effect while 2-ethoxyethanol at high concentrations intensified the hydrogen peroxide action. This study demonstrated that among the EGEs studied, 2-phenoxyethanol showed the most consistent cytotoxic effect on neurons in in vitro conditions and enhanced the hydrogen peroxide action. 2-Isopropoxyethanol had also a potent cytotoxic effect, but it did not enhance the hydrogen peroxide action, whereas 2-butoxyethanol only potentiated cytotoxic effect of H(2)O(2). It is concluded that the results of the present study should be confirmed in in vivo conditions and that some EGEs, especially 2-phenoxyethanol, 2-butoxyethanol and 2-isopropoxyethanol, may be responsible for initiation or exacerbation of neuronal cell damage.