Mitigation of arsenic driven utero-ovarian malfunction and changes of apoptotic gene expression by dietary NAC

Association between urinary arsenic and the prevalence of endometriosis in women in the United States

Background

Endometriosis affects up to 15% of women of reproductive age and can lead to various symptoms. More than 200 million people worldwide are at risk of higher than safe levels of arsenic exposure through drinking water. Studies investigating the relationship between arsenic and endometriosis are very limited and have yielded inconsistent results. This study aimed to explore the relationship between total urinary arsenic, arsenic species (Urinary arsenous acid, Urinary Arsenic acid, Urinary Arsenobetaine, Urinary Arsenocholine, Urinary Dimethylarsinic acid, Urinary Monomethylarsonic acid) and endometriosis.

Methods

We utilized a nationally representative dataset from the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2006. A total of 650 participants were included. We examined the association between total urinary arsenic and different arsenic species with endometriosis using weighted multivariate logistic regression models.

Results

Urinary arsenous acid and urinary monomethylarsonic acid (MMA) were positively correlated with endometriosis (p < 0.05). After adjusting for potential confounding factors, the positive correlation of urinary MMA remained significant (OR: 1.317, 95%CI: 1.074-1.615). Subgroup analyses and interaction tests indicated that this association was not dependent.

Conclusion

Our research underscores a significant positive association observed between factors urinary MMA and endometriosis. Future research is needed to elucidate the specific mechanisms behind this association.

Metformin Mitigates the Impact of Arsenic Exposure on the Maternal and Offspring Reproductive System of Female Mice

Exposure to arsenic causes health problems and is associated with adverse effects on fertility and development. Humans are facing increasing exposure to arsenic from multiple sources, such as drinking water, food products, and industrial processes. The mechanisms behind arsenic-induced reproductive toxicity and its impact on fertility and the development of future generations are investigated by the protective role of metformin (200 mg/kg) against arsenic-induced (20 ppm As2O3) ovarian damage in both maternal and offspring generations. Results showed arsenic exposure caused significant weight loss, increased mortality, reduced serum anti-Mullerian hormone (AMH) levels, and heightened oxidative stress, indicated by increased reactive oxygen species (ROS), malondialdehyde (MDA), and reduced ovarian antioxidant activity. Gene expression changes related to apoptosis and inflammation, such as BAX, Bcl-2, Bcl-2, caspase-3, tumor necrosis factor-alpha (TNF-α), and interleukin-1 (IL-1), were also noted, along with a decrease in HO-1 expression. Arsenic exposure led to a reduction in ovarian follicles and an increase in atretic follicles and uterine thickness. However, metformin significantly reduced ROS and MDA levels, enhanced antioxidant capacity, and protected ovarian tissue by upregulating heme oxygenase-1 (HO-1) and Bcl-2, modulating apoptotic and inflammatory genes, and preserving AMH levels. The possible protective role of metformin against arsenic-induced toxicity and its detrimental effects aims to improve therapeutic approaches to alleviate the harmful consequences of environmental pollutants, especially arsenic.

Impact of oxidative stress induced by heavy metals on ovarian function

As a crucial organ of the female reproductive system, the ovary has both reproductive and endocrine functions. Oxidative stress refers to an increase in intracellular reactive oxygen species (ROS), which play a role in the normal physiological activity of the ovary. However, excessive ROS can cause damage to the ovary. With the advancement of human industrial activities, heavy metal pollution has become increasingly severe. Heavy metals cause oxidative stress through both direct and indirect mechanisms, leading to changes in signal transduction pathways that damage the ovaries. This review aims to outline the adverse effects of oxidative stress on the ovaries triggered by heavy metals such as copper, arsenic, cadmium, mercury, and lead. The detrimental effects of heavy metals on ovaries include follicular atresia and decreased estrogen production in experimental animals, and they also cause premature ovarian insufficiency in women. Additionally, this review discusses the role of antioxidants, provides some treatment methods, summarizes the limitations of current research, and offers perspectives for future research directions.

Environmental arsenic exposure and reproductive system toxicity in male and female and mitigatory strategies: a review

Environmental Arsenic (As) exposure is one of the main health challenges in different area of the world. As is a significant factor responsible to the reproductive system toxicity in both male and female. In this study, the most important effects mechanisms and biomarkers related to environmental exposure to As and the reproductive system toxicity, and infertility risk are reviewed in male and female. The results showed that the most important As-induced reproductive system toxicity in the male were alteration in the quantity and quality of semen, testicular toxicity, oxidative stress, testosterone reduction, and sperm apoptosis. For female were oxidative stress, spontaneous miscarriage, reproductive cycle disruption, decrease in the estradiol, progesterone, and testosterone levels and impair fecundity. The main mechanisms of reproductive system toxicity caused by As exposure in male were, genotoxic effects, reduction of glutathione, disruption of sex hormones, sperm flagellum formation impairment, inhibition of spermatogenesis, disruption of cell signaling pathways, and metabolites disruption. For female were abnormal signaling in gene expression, hormonal homeostasis, As-accumulation in placental tissue and creation of reactive oxygen, disruption in the neurotransmitters balance, and sex hormones disruption. The suitable biomarkers for As-induced reproductive toxicity in male were changes in testosterone, one-carbon and lipid metabolism, noncoding RNAs, and steroid hormone homeostasis, and for female was human chorionic gonadotropin (hCG) changes. Finaly, taking selenium, zinc, silymarin, vitamins (C and E) and phytonutrients can be effective in reducing the As-induced reproductive system toxicity and infertility risk.

Attenuation of sodium arsenite mediated ovarian DNA damage, follicular atresia, and oxidative injury by combined application of vitamin E and C in post pubertal Wistar rats

Arsenic being a toxic metalloid ubiquitously persists in environment and causes several health complications including female reproductive anomalies. Epidemiological studies documented birth anomalies due to arsenic exposure. Augmented reactive oxygen species (ROS) generation and quenched antioxidant pool are foremost consequences of arsenic threat. On the contrary, Vitamin E (VE) and C (VC) are persuasive antioxidants and conventionally used in toxicity management. Present study was designed to explore the extent of efficacy of combined VE and VC (VEC) against Sodium arsenite (NaAsO2) mediated ovarian damage. Thirty-six female Wistar rats were randomly divided into three groups (Grs) and treated for consecutive 30 days; Gr I (control) was vehicle fed, Gr II (treated) was gavaged with NaAsO2 (3 mg/kg/day), Gr III (supplement) was provided with VE (400 mg/kg/day) & VC (200 mg/kg/day) along with NaAsO2. Marked histological alterations were evidenced by disorganization in oocyte, granulosa cells and zona pellucida layers in treated group. Considerable reduction of different growing follicles along with increased atretic follicles was noted in treated group. Altered activities ofΔ5 3β-Hydroxysteroid dehydrogenase and 17β-Hydroxysteroid dehydrogenase accompanied by reduced luteinizing hormone, follicle-stimulating hormone and estradiol levels were observed in treated animals. Irregular estrous cyclicity pattern was also observed due to NaAsO2 threat. Surplus ROS production affected ovarian antioxidant strata as evidenced by altered oxidative stress markers. Provoked oxidative strain further affects DNA status of ovary. However, supplementation with VEC caused notable restoration from such disparaging effects of NaAsO2 toxicities. Antioxidant and antiapoptotic attributes of those vitamins might be liable for such restoration.

Effects of N-acetyl-l-cysteine on chronic heat stress-induced oxidative stress and inflammation in the ovaries of growing pullets

The aims of this study were to investigate the effects of supplemental N-acetyl-l-cysteine (NAC) on chronic heat stress-induced oxidative stress and inflammation in the ovaries of growing pullets. A total of 120, 12-wk-old, Hy-Line Brown hens were randomly separated into 4 groups with 6 replicates of 5 birds in each group for 21 d. The 4 treatments were as follows: the CON group and CN group were supplemented with basal diet or basal diet with 1 g/kg NAC, respectively; and the HS group and HSN group were heat-stressed groups supplemented with basal diet or basal diet with 1 g/kg NAC, respectively. The results indicated that the ovaries suffered pathological damage due to chronic heat stress and that NAC effectively ameliorated these changes. Compared with the HS group, antioxidant enzyme activities (including SOD, GSH-Px, CAT, and T-AOC) were enhanced, while the MDA contents and the expression levels of HSP70 were decreased in the HSN group. In addition, NAC upregulated the expression levels of HO-1, SOD2, and GST by upregulating the activity of Nrf2 at different time points to mitigate oxidative stress caused by heat exposure. Simultaneously, NAC attenuated chronic heat stress-induced NF-κB pathway activation and decreased the expression levels of the proinflammatory cytokines IL-8, IL-18, TNF-α, IKK-α, and IFN-γ. Cumulatively, our results indicated that NAC could ameliorate chronic heat stress-induced ovarian damage by upregulating the antioxidative capacity and reducing the secretion of proinflammatory cytokines.

N-Acetylcysteine improves oocyte quality through modulating the Nrf2 signaling pathway to ameliorate oxidative stress caused by repeated controlled ovarian hyperstimulation

CONTEXT

N -acetyl-cysteine (NAC) is a potent antioxidant that can be used for many gynecological diseases such as polycystic ovary syndrome and endometriosis. Controlled ovarian hyperstimulation (COH) is a critical step in infertility treatment. Our previous clinical studies have shown that repeated COH led to oxidative stress in follicle fluid and ovarian granulosa cells.

AIMS

In this study, we investigated whether NAC could inhibit oxidative stress in mice caused by repeated COH and improve the mitochondrial function of oocytes.

METHODS

Female Institute of Cancer Research (ICR) mice were randomly assigned into three groups: normal group, model (repeated COH) group, NAC group. We examined the morphology, number and quality of mitochondria. The mechanism of regulation of nuclear factor erythroid 2-related factor 2 (Nrf2) by NAC to ameliorate oxidative stress was also investigated.

KEY RESULTS

Repeated COH caused oxidative damage in ovaries and oocytes and decreased oocyte quality, while NAC prevented oxidative damage and increased oocyte mitochondrial function. In in vitro experiments, it was verified that NAC can promote the nuclear translocation of Nrf2, which transcriptionally activates the expression of superoxide dismutase and glutathione peroxidase, which removed excessive reactive oxygen species that causes mitochondria damage.

CONCLUSIONS

The results suggest that NAC raises mitochondrial function in oocytes and improves oocyte quality through decreasing oxidative stress in mice with repeated COH. The underlying mechanism is related to the regulation of the Nrf2 signaling pathway.

IMPLICATION

This study provides a meaningful foundation for the future clinical application of NAC during repeated COH.

Heavy Metal Contamination of Natural Foods Is a Serious Health Issue: A Review

Heavy metals play an important role in the homeostasis of living cells. However, these elements induce several adverse environmental effects and toxicities, and therefore seriously affect living cells and organisms. In recent years, some heavy metal pollutants have been reported to cause harmful effects on crop quality, and thus affect both food security and human health. For example, chromium, cadmium, copper, lead, and mercury were detected in natural foods. Evidence suggests that these elements are environmental contaminants in natural foods. Consequently, this review highlights the risks of heavy metal contamination of the soil and food crops, and their impact on human health. The data were retrieved from different databases such as Science Direct, PubMed, Google scholar, and the Directory of Open Access Journals. Results show that vegetable and fruit crops grown in polluted soil accumulate higher levels of heavy metals than crops grown in unpolluted soil. Moreover, heavy metals in water, air, and soil can reduce the benefits of eating fruits and vegetables. A healthy diet requires a rational consumption of foods. Physical, chemical, and biological processes have been developed to reduce heavy metal concentration and bioavailability to reduce heavy metal aggregation in the ecosystem. However, mechanisms by which these heavy metals exhibit their action on human health are not well elucidated. In addition, the positive and negative effects of heavy metals are not very well established, suggesting the need for further investigation.

NAC antagonizes arsenic-induced neurotoxicity through TMEM179 by inhibiting oxidative stress in Oli-neu cells

Arsenic is one of the most common environmental pollutants. Neurotoxicity induced by arsenic has become a major public health concern. However, the effects of arsenic-induced neurotoxicity in the brain and the underlying molecular mechanisms are not well understood. N-acetyl-cysteine (NAC) is a thiol-based antioxidant that can antagonize heavy metal-induced neurotoxicity by scavenging reactive oxygen species (ROS). Here, we used the mouse oligodendrocyte precursor cell (OPC) line Oli-neu to explore the neurotoxic effects of arsenic and the protective effects of NAC. We found that arsenic exposure decreased cell viability, increased oxidative stress, caused mitochondrial dysfunction, and led to apoptosis of Oli-neu cells. Furthermore, we revealed that NAC treatment reversed these neurotoxic effects of arsenic. TMEM179, a key membrane protein, was found highly expressed in OPCs and to be an important factor in maintaining mitochondrial functions. We found that TMEM179 played a critical role in mediating the neurotoxic effects of arsenic and the protective role of NAC. PKCβ is a downstream factor through which TMEM179 regulates the expression of apoptosis-related proteins. This study improves our understanding of the neurotoxic effects and mechanisms of arsenic exposure and the protective effects of NAC. It also identifies a potential molecular target, TMEM179, for the treatment of arsenic-induced neurotoxicity.

Arsenic-induced uterine apoptotic damage is protected by ethyl acetate fraction of Camellia sinensis (green tea) via Bcl-2-BAX through NF-κB regulations in Wistar rats

The non-invasive treatment strategy is indispensable to overcome the side effects of conventional treatment with chelating agents against arsenic. Presence of catechins and flavonoids in Camellia sinensis have potential antioxidant properties and other beneficial effects. The aim of the study was to explore the curative potential role of Camellia sinensis against uterine damages produced by sodium arsenite in mature albino rats. A dose of 10 mg of Camellia sinensis ethyl acetate (CS-EA) fraction/100 gm body weight was provided to the sodium arsenite-treated rats (10 mg/Kg body weight). LC-MS analysis was used for the detection of active component in CS-EA fraction. Enzymatic antioxidants analysis carried out by reproducible native gel technique. Hormones and some pro and anti-inflammatory markers were detected by ELISA, PCR, and western blot techniques respectively. Immunostaining was performed for the detection of estradiol receptor alpha. LC-MS analysis of CS-EA fraction ensured the presence of active tea polyphenol and tea catechin of which highest peak of epigallocatechin-3 gallate (EGCG) was obtained in this study. Significant elevations of lipid peroxidation end products followed by the diminution of antioxidant enzymes activities were noted in arsenicated rats which were capably retrieved by the treatment of CS-EA fraction. Post-treatment with CS-EA fraction meaningfully improved gonadotrophins and estradiol signalling in association with a highly expressing estradiol receptor-α (ERα) in the ovary and uterus followed by the maintenance of normal utero-ovarian histoarchitecture in arsenic fed rats. CS-EA fractioned treated group overturned the sodium arsenite driven higher expression of pro-inflammatory cytokines and proapoptotic markers along with a low level of anti apoptotic Bcl-2 expression and comparatively lower NF-κB signalling in the uterus via regulating IKK β kinase mostly by EGCG of CS-EA fraction. However, ethyl acetate fraction of Camellia sinensis played a critical role in minimizing arsenic-mediated uterine hypo-function.