Protective Effects of Combined Selenium and Punica granatum Treatment on Some Inflammatory and Oxidative Stress Markers in Arsenic-Induced Hepatotoxicity in Rats

Mechanisms of Metal-Induced Hepatic Inflammation

PURPOSE OF REVIEW

Worldwide, there is an increasing prevalence of hepatic diseases. The most common diseases include alcoholic-associated liver disease (ALD), metabolic dysfunction-associated fatty liver disease/ metabolic dysfunction-associated steatohepatitis (MAFLD/MASH) and viral hepatitis. While there are many important mediators of these diseases, there is increasing recognition of the importance of the inflammatory immune response in hepatic disease pathogenesis.

RECENT FINDINGS

Hepatic inflammation triggers the onset and progression of liver diseases. Chronic and sustained inflammation can lead to fibrosis, then cirrhosis and eventually end-stage cancer, hepatocellular carcinoma. Importantly, growing evidence suggest that metal exposure plays a role in hepatic disease pathogenesis. While in recent years, studies have linked metal exposure and hepatic steatosis, studies emphasizing metal-induced hepatic inflammation are limited. Hepatic inflammation is an important hallmark of fatty liver disease. This review aims to summarize the mechanisms of arsenic (As), cadmium (Cd) and chromium (Cr)-induced hepatic inflammation as they contribute to hepatic toxicity and to identify data gaps for future investigation.

Zingerone effects on arsenic-induced glucose intolerance and hepatotoxicity in mice via suppression of oxidative stress-mediated hepatic inflammation and apoptosis

BACKGROUND

Arsenic (As), a poisonous metalloid, is widely distributed in air, water, and soil and has been associated with the occurrence of diabetes and liver toxicity. Zingerone (ZNG), one of the active compounds in ginger, has several pharmacological benefits such as antioxidant and anti-inflammatory characteristics. The objective of this research was to assess the protective role of ZNG against arsenic (As)-induced glucose intolerance (GI) and hepatotoxicity in mice.

METHODS

Male NMRI mice were treated with ZNG (25, 50, and 100 mg/kg, oral gavage for 29 days) before As administration (10 mg/kg, oral gavage for 29 days). On the 29th day, fasting blood glucose (FBG) and glucose tolerance test were measured. The animals were euthanized (day 30), and samples from blood and tissue (liver and pancreas) were gathered for further evaluations.

RESULTS

Administration of ZNG inhibited As-induced elevation of FBG and GI. Moreover, hepatic tissue damage and decreased Langerhans islets' diameter caused by As administration were improved by ZNG treatment. Pretreatment with ZNG attenuated the elevation of serum liver enzymes induced by As (alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase). Also, the reduction in total thiol content, as well as the decline in antioxidant enzyme activities (catalase, superoxide dismutase, and glutathione peroxidase) and the increase in lipid peroxidation marker (thiobarbituric acid reactive substances) in the liver tissue of As-exposed mice were reversed in ZNG-treated mice. Furthermore, ZNG prevented the increase of hepatic inflammatory markers (nitric oxide and tumor necrosis factor-alpha levels, and protein expression of nuclear factor-kappa B) and apoptosis-related marker (caspase-3 protein expression) in As-treated mice.

CONCLUSIONS

This study has provided evidence indicating that ZNG can act as a beneficial agent in preventing As-induced hepatotoxicity and diabetes.

The Nephroprotective Effect of Punica granatum Peel Extract on LPS-Induced Acute Kidney Injury

Sepsis is an exaggerated immune response resulting from systemic inflammation, which can damage tissues and organs. Acute kidney injury has been detected in at least one-third of patients with sepsis. Sepsis-associated acute kidney injury increases the risk of a secondary infection. Rapid diagnosis and appropriate initiation of antibiotics can significantly reduce mortality and morbidity. However, microorganisms are known to develop resistance to antibiotics. Estimations indicate that the annual casualties caused by microbial resistance will surpass cancer fatalities by 2050. The prevalence of bacterial infections and their growing antibiotic resistance has brought immediate attention to the search for novel treatments. Plant-derived supplements contain numerous bioactive components with therapeutic potential against a variety of conditions, including infections. Punica granatum peel is rich in phenolic compounds. The purpose of this study was to determine the anti-inflammatory and anti-bacterial properties of P. granatum peel extract (PGPE) on lipopolysaccharide (LPS)-induced acute kidney injury. Experimental groups were Control, LPS (10 mg/kg LPS, intraperitoneally), PGPE100, and PGPE300 (100 and 300 mg/mL PGPE via oral gavage, respectively, for 7 days). According to biochemical results, serum blood urea nitrogen (BUN), creatinine (Cr) and C-reactive protein (CRP), kidney tissue thiobarbituric acid reactive substances (TBARS), and reduced glutathione (GSH) levels significantly decreased in the PGPE groups compared to the LPS group. Histopathological and immunohistochemical findings revealed that toll-like receptor 4 (TLR4) level and nuclear factor kappa B (NF-κB) expression increased in the LPS group compared to the Control group. In addition, the anti-Gram-negative activity showed a dose-dependent effect on Acinetobacter baumannii, Escherichia coli, and Pseudomonas aeruginosa with the agar well diffusion method and the minimal inhibitory concentration (MIC). The MIC value was remarkable, especially on A. baumannii. We conclude that PGPE has the potential to generate desirable anti-bacterial and anti-inflammatory effects on LPS-induced acute kidney injury in rats.

Selenium Improves Arsenic-Induced Male Reproductive Dysfunction by Regulating H3K14ac Level

Arsenic exposure has been known to be associated with male reproduction injury. Exploring the antidote of arsenic and ascertaining proper dose of antidote are important for detoxifying the male reproductive toxicity of arsenic. Selenium, which is essential for the male reproduction and spermatogenesis, can alleviate the toxicity of many environmental toxins, such as metals, and fluoride (F). Selenium relieves arsenic-induced reductions in spermatogenesis index and testicular function marker enzymes via promoting the antioxidative ability of rats. Our previous study has found that arsenic can induce male reproductive toxicity by affecting the level of H3K14ac in the testis, so we further investigate whether selenium can antagonize arsenic-induced male reproductive toxicity through the H3K14ac pathway and ascertain the appropriate dose of selenium. The results show that selenium intervention reduces the accumulation of arsenic in rat testis probably attributing to promote the excretion of arsenic from rat, then improves the testis injury induced by arsenic. Selenium intervention enhances sperm quality, testosterone level, and expression of steroidogenic genes by regulating H3K14ac level and expression of its associated enzymes (KAT2A, BAZ2A, and HDAC6), and thus alleviates the male reproductive toxicity of arsenic, and the proper dose of Se for mitigating arsenic male reproductive toxicity is 1 mg/kg.

Arsenic toxicity: sources, pathophysiology and mechanism

Background

Arsenic is a naturally occurring element that poses a significant threat to human health due to its widespread presence in the environment, affecting millions worldwide. Sources of arsenic exposure are diverse, stemming from mining activities, manufacturing processes, and natural geological formations. Arsenic manifests in both organic and inorganic forms, with trivalent meta-arsenite (As3+) and pentavalent arsenate (As5+) being the most common inorganic forms. The trivalent state, in particular, holds toxicological significance due to its potent interactions with sulfur-containing proteins.

Objective

The primary objective of this review is to consolidate current knowledge on arsenic toxicity, addressing its sources, chemical forms, and the diverse pathways through which it affects human health. It also focuses on the impact of arsenic toxicity on various organs and systems, as well as potential molecular and cellular mechanisms involved in arsenic-induced pathogenesis.

Methods

A systematic literature review was conducted, encompassing studies from diverse fields such as environmental science, toxicology, and epidemiology. Key databases like PubMed, Scopus, Google Scholar, and Science Direct were searched using predetermined criteria to select relevant articles, with a focus on recent research and comprehensive reviews to unravel the toxicological manifestations of arsenic, employing various animal models to discern the underlying mechanisms of arsenic toxicity.

Results

The review outlines the multifaceted aspects of arsenic toxicity, including its association with chronic diseases such as cancer, cardiovascular disorders, and neurotoxicity. The emphasis is placed on elucidating the role of oxidative stress, genotoxicity, and epigenetic modifications in arsenic-induced cellular damage. Additionally, the impact of arsenic on vulnerable populations and potential interventions are discussed.

Conclusions

Arsenic toxicity represents a complex and pervasive public health issue with far-reaching implications. Understanding the diverse pathways through which arsenic exerts its toxic effects is crucial to developing effective mitigation strategies and interventions. Further research is needed to fill gaps in our understanding of arsenic toxicity and to inform public health policies aimed at minimising exposure.Arsenic toxicity is a crucial public health problem influencing millions of people around the world. The possible sources of arsenic toxicity includes mining, manufacturing processes and natural geological sources. Arsenic exists in organic as well as in inorganic forms. Trivalent meta-arsenite (As3+) and pentavalent arsenate (As5+) are two most common inorganic forms of arsenic. Trivalent oxidation state is toxicologically more potent due to its potential to interact with sulfur containing proteins. Humans are exposed to arsenic in many ways such as environment and consumption of arsenic containing foods. Drinking of arsenic-contaminated groundwater is an unavoidable source of poisoning, especially in India, Bangladesh, China, and some Central and South American countries. Plenty of research has been carried out on toxicological manifestation of arsenic in different animal models to identify the actual mechanism of aresenic toxicity. Therefore, we have made an effort to summarize the toxicology of arsenic, its pathophysiological impacts on various organs and its molecular mechanism of action.

Dapagliflozin alleviates arsenic trioxide-induced hepatic injury in rats via modulating PI3K/AkT/mTOR, STAT3/SOCS3/p53/MDM2 signaling pathways and miRNA-21, miRNA-122 expression

Dapagliflozin (DPG) is a sodium-glucose co-transporter 2 inhibitor that is commonly used in the treatment of type 2 diabetes. However, studies have shown that DPG has a protective effect under a variety of experimental conditions through its antioxidative and anti-inflammatory properties. DPG's effect on experimental hepatotoxicity caused by arsenic trioxide (ATO) has yet to be investigated. The purpose of this study was to investigate the protective effect of DPG in preventing hepatic damage caused by ATO and discover the underlying mechanisms. The effect of DPG (1 mg/kg, orally) on ATO (5 mg/kg, i.p.)-induced hepatic injury was evaluated in rats. Serum liver function parameters, as well as oxidative stress biomarkers and inflammatory cytokine levels were assessed. Histopathological changes in the liver were detected using H&E staining. Using Western blotting and PCR techniques, the molecular mechanisms of DPG in ameliorating hepatic injury were investigated. DPG improved liver function by inhibiting histopathological changes, decreasing levels of hepatic function and toxicity parameters measured in both serum and tissues, and exhibiting antioxidant and anti-inflammatory effects, according to the findings. Consistent with the PCR results, DPG also decreased the expression of LC3-II, micro-RNA-122, and micro-RNA-21 while increased the expression of SOCS3. Furthermore, according to western blotting results, DPG was able to reduce the protein expression of AKT, mTOR, PI3K, and STAT3. Although further clinical research is necessary, this study highlights the potential of DPG in preventing liver damage in a rat model of hepatotoxicity induced by ATO.

Melatonin attenuates liver injury in arsenic-treated rats: The potential role of the Nrf2/HO-1, apoptosis, and miR-34a/Sirt1/autophagy pathways

Arsenic is a toxic metalloid found in the environment in different organic and inorganic forms. Molecular mechanisms implicated in arsenic hepatotoxicity are complex but include oxidative stress, apoptosis, and autophagy. The current study focused on the potential protective capacity of melatonin against arsenic-induced hepatotoxicity. Thirty-six male Wistar rats were allocated into control, arsenic (15 mg/kg; orally), arsenic (15 mg/kg) plus melatonin (10, 20, and 30 mg/kg; intraperitoneally), and melatonin alone (30 mg/kg) groups for 28 days. After the treatment period, the serum sample was separated to measure liver enzymes (AST and ALT). The liver tissue was removed and then histological alterations, oxidative stress markers, antioxidant capacity, the levels of Nrf2 and HO-1, apoptosis (Bcl-2, survivin, Mcl1, Bax, and caspase-3), and autophagy (Sirt1, Beclin-1, and LC3 II/I ratio) proteins, as well as the expression level of miR-34a, were evaluated on this tissue. Arsenic exposure resulted in the enhancement of serum AST, ALT, and substantial histological damage in the liver. Increased levels of malondialdehyde, a lipid peroxidation marker, and decreased levels of physiological antioxidants including glutathione, superoxide dismutase, and catalase were indicators of arsenic-induced oxidative damage. The levels of Nrf2, HO-1, and antiapoptotic proteins diminished, while proapoptotic and autophagy proteins were elevated in the arsenic group concomitant with a low level of hepatic miR-34a. The co-treatment of melatonin and arsenic reversed the changes caused by arsenic. These findings showed that melatonin reduced the hepatic damage induced by arsenic due to its antioxidant and antiapoptotic properties as well as its regulatory effect on the miR-34a/Sirt1/autophagy pathway.

Selenium and zinc alleviate hepatotoxicity induced by heavy metal mixture (cadmium, mercury, lead and arsenic) via attenuation of inflammo-oxidant pathways

Heavy metals (HM) are believed to be injurious to humans. Man is exposed to them on daily basis unknowingly, with no acceptable protocol to manage its deleterious effects. These metals occur as mixture of chemicals with varying concentrations in our atmosphere. There are growing calls for the use of essential metals in mitigating the injurious effects induced by heavy metals exposure to man; therefore, the aim of this study was to evaluate the protective effects of essential metals (Zinc and Selenium) in a mixture of heavy metal toxicity. In this study, except for negative controls, all other groups were treated with lead (PbCl2 , 20 mg kg-1 ); cadmium (CdCl2 , 1.61 mg kg-1 ); mercury (HgCl2 , 0.40 mg kg-1 ), and arsenic (NaAsO3, 10 mg kg-1 ) that were formed in distilled water. Pb, Cd, As, and Hg were administered as mixtures to 35, 6 weeks old rats weighing between 80 to 100 g for 60 days. Group I served as normal control without treatment, group II positive control received HM mixture, while groups III to V received HMM with Zn, Se, and Zn + Se respectively. Animal and liver weights, HM accumulation in the liver, food intake (FI), water intake (WI), liver function test, malondialdehyde (MDA), and inflammatory/transcription factor/apoptosis markers were checked. Also, antioxidant enzymes, and histological studies were carried out. Metal mixture accumulated in the liver and caused toxicities which were ameliorated by Zn and Se administration. HM caused significant decrease in FI, WI and distorted the level of liver enzymes, lipid peroxidation, inflammatory markers, antioxidants and architecture of the liver. Co administration with Zn or Se or both reversed the distortions. This study lays credence to the evolving research on the public health implications of low dose metal mixtures and the possible ameliorative properties of Zn and Se.

Zinc and selenium attenuate quaternary heavy metal mixture-induced testicular damage via amplification of the antioxidant system, reduction in metal accumulation, inflammatory and apoptotic biomarkers

Heavy metals (HMs) such as cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg) are highly toxic elements. They are often found together in nature as a heavy metal mixture (HMM) and are known to contribute to subfertility/infertility as environmental pollutants. This study aims to evaluate the potential benefits of treating HMM-induced testicular pathophysiology with zinc (Zn) and/or selenium (Se). Six-week-old male Sprague Dawley rats were grouped into 5 (n = 7). The control group received deionized water, while the other groups were treated with PbCl2 (20 mg kg-1), CdCl2 (1.61 mg kg-1), HgCl2 (0.40 mg kg-1), and Na2AsO3 (10 mg kg-1) in deionized water for 60 days. Additionally, groups III to V received Zn, Se, and Zn/Se, respectively, for 60 days. The study evaluated testis weight, metal accumulation, sperm analysis, FSH, LH, testosterone, prolactin, oxidative stress, antioxidants, pro-inflammatory and apoptotic markers, and presented structural changes in the testis as micrographs. HMM caused a significant increase in testis weight, metal accumulation, prolactin, oxidative stress, and pro-inflammatory and apoptotic markers, while significantly decreasing semen analysis, FSH, LH, and testosterone. Histology showed decreased spermatogenesis and spermiogenesis, as evidenced by the structure of the germ cells and spermatids. However, Zn, Se, or both ameliorated and reversed some of the observed damages. This study provides further evidence for the mitigative potential of Zn, Se, or both in reversing the damage inflicted by HMM in the testis, and as a countermeasure towards improving HM-induced decrease in public health fecundity.

Graphical abstract

Arsenic-induced toxicity and the ameliorative role of antioxidants and natural compounds

Arsenic (As) poisoning has proven to be a major threat worldwide because of its toxic effects on the human body. As toxicity through drinking water is a global health concern. The toxicity of As is known to affect the liver, kidney, lungs, muscles, cardiovascular system, and nervous system and can even induce diabetes. Further As can cause skin lesions leading to notable diseases in the skin like Bowen's disease. Chronic exposure to As has caused many tragedies in Eastern, and several Southeast Asian and Latin American countries. Long-term exposure to As makes it an immediate threat that should be dealt with as a priority, and one of the ways to handle it may be with the use of antioxidants. In this review, we have discussed the natural and anthropogenic sources of As, its metabolism, pathophysiology, and mechanism of toxicity. Besides, we have also discussed some of the synthetic chelators and the ameliorative role of antioxidants and natural compounds in reducing As toxicity.

Protective effects of pomegranate (Punica granatum) and its main components against natural and chemical toxic agents: A comprehensive review

BACKGROUND

Different chemical toxicants or natural toxins can damage human health through various routes such as air, water, fruits, foods, and vegetables.

PURPOSE

Herbal medicines may be safe and selective for the prevention of toxic agents due to their active ingredients and various pharmacological properties. According to the beneficial properties of pomegranate, this paper summarized the protective effects of this plant against toxic substances.

STUDY DESIGN

In this review, we focused on the findings of in vivo and in vitro studies of the protective effects of pomegranate (Punica granatum) and its active components including ellagic acid and punicalagin, against natural and chemical toxic agents.

METHODS

We collected articles from the following databases or search engines such as Web of Sciences, Google Scholar, Pubmed and Scopus without a time limit until the end of September 2022.

RESULTS

P. granatum and its constituents have shown protective effects against natural toxins such as aflatoxins, and endotoxins as well as chemical toxicants for instance arsenic, diazinon, and carbon tetrachloride. The protective effects of these compounds are related to different mechanisms such as the prevention of oxidative stress, and reduction of inflammatory mediators including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), cyclooxygenase-2(COX-2) and nuclear factor ĸB (NF-ĸB) as well as the modulation of apoptosis, mitogen-activated protein kinase (MAPK) signaling pathways and improvement of liver or cardiac function via regulation of enzymes.

CONCLUSION

In this review, different in vitro and in vivo studies have shown that P. granatum and its active constituents have protective effects against natural and chemical toxic agents via different mechanisms. There are no clinical trials on the protective effects of P. granatum against toxic agents.

Ethanol Extracts of Eriobotrya japonica (Loquat) Seeds, Leaves, and Fruits Have Anti-obesity and Hypolipidemic Effects in Rats

Background:

Obesity is a serious public health problem contributing to development of several diseases, including hyperlipidemia, hyperglycemia, and hypertension. The plant Eriobotrya japonica (loquat) has been used in traditional Chinese medicine to treat many ailments and traditional healers used it to reduce weight.

Objective:

To examine the potential anti-obesity and hypolipidemic effects of ethanol extract of loquat in rats.

Materials and Methods:

Loquat leaves, fruits, or seeds were extracted with ethanol. About 96 Wistar male rats were fed either a normal rat diet (normal control group; group 1) or a high-fat diet (HFD) for 12 weeks (obese; groups 2−12). Obese rats were divided into11 groups as follows: (obese control: group 2) (obese positive control which received the hypolipidemic reference drug atorvastatin: group 3). Groups (4−6), (7−9), and (10−12) were given seed, leaf, or fruit extract, respectively, at 40,100, and 400 mg/kg. Body weight, serum glucose, lipid profile, creatinine, liver enzymes, albumin, and total protein were measured weekly.

Results:

HFD consumption significantly increased body weight and serum total cholesterol (TC), triglycerides (TGs), low-density lipoprotein (LDL), very-low density lipoprotein (VLDL), and glucose and decreased HDL compared to rats fed the normal diet. HFD also increased serum glutamic-oxaloacetic transaminase (GOT), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP) and creatinine but decreased serum albumin and total protein. Administration of E. japonica seed, leaf, or fruit extract significantly decreased body weight, TC, TGs, LDL, VLDL, glucose, liver, and renal enzymes but increased HDL, albumin, and total protein levels.

Conclusion:

E. japonica seed, leaf, and fruit ethanol extract regulates body weight gain, has hypolipidemic properties, and positively affects liver and kidney enzymes.

Protective effect of starch-stabilized selenium nanoparticles against melamine-induced hepato-renal toxicity in male albino rats

Melamine and its analogues are illegally added to raise the apparent protein content in foods. The elevated concentrations of these compounds cause adverse effects in humans and animals. In this contribution, the protective effects of the synthesized starch-stabilized selenium nanoparticles (Se-NPs@starch) on melamine-induced hepato-renal toxicity have been systematically investigated. The Se-NPs@starch were characterized by X-ray photoelectron spectroscopy (XPS) analysis, energy dispersive spectroscopy (EDS) mapping analysis, TEM, and FT-IR. Starch plays a crucial role in the stabilization and dispersion of Se NPs, as noticed from the TEM and EDS investigations. Furthermore, the atomic ratio of Se distribution over the starch surface is approximately 1.67%. The current study was conducted on four groups of adult male rats, and the oral daily treatments for 28 days were as follows: group I served as control, group II received Se-NPs@starch, group III was exposed to melamine, while group IV was treated with melamine and Se-NPs@starch. The results reveal a significant alteration in the histoarchitecture of both hepatic and renal tissues induced by melamine. Furthermore, elevated liver and kidney function markers, high malondialdehyde, and increased expression levels of apoptosis-related genes besides a reduction in GSH and expression levels of antioxidant genes were observed in the melamine-exposed group. Interestingly, the administration of the Se-NPs@starch resulted in remarkable protection of rats against melamine-induced toxicity through increasing the antioxidant capacity and inhibiting oxidative damage. Collectively, this study provides affordable starch-stabilized Se-NPs with potent biological activity, making them auspicious candidates for prospective biomedical applications.

DL-Selenomethionine Alleviates Oxidative Stress Induced by Zearalenone via Nrf2/Keap1 Signaling Pathway in IPEC-J2 Cells

Zearalenone (ZEN) is a kind of nonsteroidal mycotoxin that is considered a risk affecting the safety of human food and livestock feed that causes oxidative damages in mammalian cells. Selenomethionine (SeMet) was indicated to have antioxidant activity and received great interest in investigating the role of SeMet as a therapeutic agent in oxidation. Therefore, the aim of this study was to investigate the hormetic role of DL-SeMet in porcine intestinal epithelial J2 (IPEC-J2) cells against ZEN-induced oxidative stress injury. As a result of this experiment, 30 μg/mL of ZEN was observed with significantly statistical effects in cell viability. Following the dose-dependent manner, 20 μg/mL was chosen for the subsequent experiments. Then, further results in the current study showed that the ZENinduced oxidative stress with subsequent suppression of the expression of antioxidant stress pathway-related genes species. Moreover, SeMet reversed the oxidative damage and cell death of ZEN toxins to some extent, by a Nrf2/Keap1-ARE pathway. The finding of this experiment provided a foundation for further research on the ZEN-caused cell oxidative damage and the cure technology.

Antioxidant Therapy in Pancreatitis

Pancreatitis is pathologic inflammation of the pancreas characterized by acinar cell destruction and oxidative stress. Repeated pancreatic insults can result in the development of chronic pancreatitis, characterized by irreversible fibrosis of the pancreas and many secondary sequelae, ultimately leading to the loss of this important organ. We review acute pancreatitis, chronic pancreatitis, and pancreatitis-related complications. We take a close look at the pathophysiology with a focus on oxidative stress and how it contributes to the complications of the disease. We also take a deep dive into the evolution and current status of advanced therapies for management including dietary modification, antioxidant supplementation, and nuclear factor erythroid-2-related factor 2-Kelch-like ECH-associated protein 1(Nrf2-keap1) pathway activation. In addition, we discuss the surgeries aimed at managing pain and preventing further endocrine dysfunction, such as total pancreatectomy with islet auto-transplantation.

Exploration of the hepatoprotective effect and mechanism of magnesium isoglycyrrhizinate in mice with arsenic trioxide‑induced acute liver injury

Arsenic trioxide (ATO)-induced hepatotoxicity limits the therapeutic effect of acute myelogenous leukemia treatment. Magnesium isoglycyrrhizinate (MgIG) is a natural compound extracted from licorice and a hepatoprotective drug used in liver injury. It exhibits anti-oxidant, anti-inflammatory and anti-apoptotic properties. The aim of the present study was to identify the protective action and underlying mechanism of MgIG against ATO-induced hepatotoxicity. A total of 50 mice were randomly divided into five groups (n=10/group): Control; ATO; MgIG and high- and low-dose MgIG + ATO. Following continuous administration of ATO for 7 days, the relative weight of the liver, liver enzyme, histological data, antioxidant enzymes, pro-inflammatory cytokines, cell apoptosis and changes in Kelch-like ECH-associated protein 1/nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2) signaling pathway were observed. MgIG decreased liver injury, decreased the liver weight and liver index, inhibited oxidative stress and decreased the activity of glutathione, superoxide dismutase and catalase, production of reactive oxygen species and levels of pro-inflammatory cytokines, including IL-1β, IL-6 and TNF-α. Western blotting showed a decrease in Bax and caspase-3. There was decreased cleaved caspase-3 expression and increased Bcl-2 expression. MgIG notably activated ATO-mediated expression of Keap1 and Nrf2 in liver tissue. MgIG administration was an effective treatment to protect the liver from ATO-induced toxicity. MgIG maintained the level of Nrf2 in the liver and protected the antioxidative defense system to attenuate oxidative stress and prevent ATO-induced liver injury.

Sodium arsenite induces spatial learning and memory impairment associated with oxidative stress and activates the Nrf2/PPARγ pathway against oxidative injury in mice hippocampus

Arsenic (As) is a ubiquitous environmental and industrial toxin with known correlates of oxidative stress and cognitive deficits in the brain. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcriptional factor that represents a central cellular antioxidant defense mechanism and transcribes many antioxidant genes. Peroxisome proliferator-activated receptor-gamma (PPARγ) is a well-known nuclear receptor to regulate lipid metabolism in many tissues, and it has been also associated with the control of oxidative stress, neuronal death, neurogenesis and differentiation. The role of Nrf2 and PPARγ in As-induced neurotoxicity is still debated. The present study was designed to investigate the neurobehavioral toxic effect of sub-chronic and middle-dose sodium arsenite exposure in mice hippocampus, as well as the response of Nrf2/PPARγ expression and influence on protein expression levels of their downstream antioxidant genes. Our results showed that mice treated with intraperitoneal injection of sodium arsenite (50 mg/kg body wt.) twice a week for 7 weeks resulted in increased generation of reactive oxygen species and impairment of spatial cognitive function. The present study also found a positive association between Nrf2/PPARγ expression in hippocampus of mice, and activation of antioxidant defenses by the evidently upregulated expression of their downstream genes, including superoxide dismutase, heme oxygenase-1 and glutathione peroxidase-3. Therefore, our findings were helpful for further understanding the role of Nrf2/PPARγ feedback loop in As-induced neurobehavioral toxicity.

Mechanisms involved in the possible protective effect of chrysin against sodium arsenite-induced liver toxicity in rats

Arsenic as a one of the most important toxic metals could induce hepatotoxicity. Previous reports revealed the significance of oxidative stress in promoting of arsenic-induced liver toxicity. The aim of the present investigation is to evaluate the effect of chrysin (CHR), a natural flavonoid with potent antioxidant activity, against sodium arsenite (SA)-induced hepatotoxicity. Thirty male Wistar rats were divided into four groups: Group 1: received normal saline (2 ml/kg/day, orally for 21 days), Group 2: received SA (10 mg/kg/day, orally for 14 days), Group 3, 4 and 5: received CHR (25, 50 and 100 mg/kg/day, respectively, orally for 21 days) and SA (10 mg/kg/day, orally for 14 days) from the 7th day. Serum levels of alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase were evaluated. Moreover, liver glutathione peroxidase and myeloperoxidase activity as well as levels of protein carbonylation, malondialdehyde, glutathione, catalase, nitric oxide, superoxide dismutase, tumor necrosis factor-α and interleukin-1β were evaluated. Moreover, histological evaluation was done. Our results revealed that treatment with CHR (more potentially at the dose of 100 mg/kg/day) before and alongside with SA significantly mitigated the SA-induced hepatotoxicity. Also, the hepatoprotective effect of CHR was verified by the histological evaluation of the liver. The results of current study demonstrated that CHR (100 mg/kg/day) could mitigate the oxidative stress and inflammation induced by SA in liver tissue.

An appraisal on molecular and biochemical signalling cascades during arsenic-induced hepatotoxicity

Arsenic is a ubiquitous metalloid compound commonly found in the environment, and it is usually found in combination with sulphur and metals. Arsenic is considered as a therapeutic as well as poisoning agent since ancient times. It causes toxic effects on different organs, mainly the liver. In this review, we focused on the molecular mechanism of arsenic-induced hepatotoxicity. Here we envisaged the bridge between arsenic and hepatotoxicity with particular focus on the level of hepatic enzymes such as ALT, AST, and ALP. Here, we attempted to elucidate the role of arsenic in redox imbalance on increased oxidative stress (elevated level of ROS, MDA and NO) and decreased antioxidant levels such as reduced GSH, catalase, and SOD. Oxidative stress induces mitochondrial dysfunction via apoptosis (AKT-PKB, MAPK, PI3/AKT, PKCδ-JNK, AKT/ERK, p53 pathways), fibrosis (TGF-β/Smad pathway), and necrosis and inflammation (TNF-α, NF-ĸB, IL-1, and IL-6). Along with that, arsenic activates caspases and Bax, decreases Bcl2 through mitochondrial dysfunction, and induces apoptosis regulatory mechanism. We believe the alteration of all these pathways leads to arsenic-induced hepatotoxicity.

Plant Extracts and Isolated Compounds Reduce Parameters of Oxidative Stress Induced by Heavy Metals: An up-to-Date Review on Animal Studies

BACKGROUND

Heavy metals are elements that are naturally found in the earth. They are used in many modern-day applications in agriculture, medicine, and industry. Heavy metal poisoning occurs when the body's soft tissues absorb too much of a particular metal. The heavy metals of interest for this review paper were cadmium, arsenic, mercury, and lead since these are the most common metals that the human body can absorb in toxic amounts. Different plant species were investigated in recent years for their effect on oxidative stress parameters after intoxication with heavy metals.

OBJECTIVES

This review paper is focused on the current update to research on heavy metals induced oxidative stress in animal models and improvement of the oxidative stress parameters upon/co-/after treatment with different plant extracts and isolated compounds.

METHODS

The available literature was screened for the novel data regarding the influence of plant extracts and compounds on heavy metals induced oxidative stress. For that purposes Scopus database was used, looking for the publications in the last 5-10 years with the key terms: plant extracts, oxidative stress, in vivo, cadmium, lead, mercury and arcenic.

RESULTS

Various parameters of oxidative stress were investigated, and their improvement with plant extracts/ compounds was observed in the brain, lungs, kidneys, liver, uterus, testis, thymus, spleen, heart, skin and blood of experimental animals. Common parameters used to determine oxidative stress in animals were: superoxide dismutase; catalase; reduced glutathione; glutathione reductase; glutathione-S-transferase; glutathione peroxidase; lipid peroxidation; oxidized glutathione; malondialdehyde; xanthine oxidase; nonprotein-soluble thiol; thioredoxin reductase; total sulphydryl group; nitric oxide; γ-glutamyl cysteine synthetase.

CONCLUSION

The most investigated species for antioxidant effects upon intoxication with heavy metals seem to be Allium sp., Bacopa monniera, Camellia sinensis, Moringa oleifera, Vitis vinifera and Zingiber officinale. According to literature data, the most promising effect to alleviate symptoms of intoxication was achieved with proanthocyanidins obtained from Vitis vinifera.

The Role of Selenium in Arsenic and Cadmium Toxicity: an Updated Review of Scientific Literature

Arsenic (As) and cadmium (Cd) are elements arousing major public health concerns associated with environmental pollution, high toxicity potential, and carcinogenic nature. However, selenium (Se) at low doses and incorporated into enzymes and proteins has antioxidant properties and protects animals and humans from the risk of various diseases. It also has an exceptionally narrow range between necessary and toxic concentrations, which is a well-known hindrance in its use as a dietary supplement. The present article aims to update and expand the role of Se in As and Cd toxicity discussed in our earlier paper. In general, recent reports show that Se, regardless of its form (as selenite, selenomethionine, nanoSe, or Se from lentils), can reduce As- or Cd-mediated toxicity in the liver, kidney, spleen, brain, or heart in animal models and in cell culture studies. As was suggested in our earlier review, Se antagonizes the toxicity of As and Cd mainly through sequestration of these elements into biologically inert complexes and/or through the action of Se-dependent antioxidant enzymes. An increase in the As methylation efficiency is proposed as a possible mechanism by which Se can reduce As toxicity. However, new studies indicate that Se may also diminish As or Cd toxicity by activation of the Nrf2 pathway. In addition, this paper discusses possible signs of Se toxic effects, which may be a challenge for its future use in the therapy of As and Cd poisoning and provide future directions to address this issue.

The effect of Punica granatum L. flower extract on post-surgical peritoneal adhesions in a rat model

OBJECTIVE

Peritoneal adhesions may develop after every abdominopelvic surgery. Many agents and technical modifications have been investigated to minimize adhesions. Punica granatum (pomegranate) flower has some anti-inflammatory and antioxidative effects that would reduce the formation of peritoneal adhesions. In the present study, the effects of different doses of oral Punica granatum flower extract on postoperative peritoneal adhesions were evaluated in a rat model.

STUDY DESIGN

Thirty-two female Wistar rats were divided into four groups: one control group (CG) and three experimental groups, treated with 100 (EG100), 200 (EG200), and 400 (EG400) mg/kg/day Punica granatum extract orally for eight days. Induction of peritoneal adhesions was done in all groups using the same method. Two weeks after the first surgery, all rats re-operated and adhesions were evaluated via both macroscopic and microscopic changes.

RESULTS

We observed that rats in the control group had statistically higher adhesion area and more severe adhesions when compared to all experimental groups. Besides, those in the EG-400 group had a significantly lower rate of foreign body reaction in serosal layer when compared to the other three study groups. Other microscopic findings were comparable between the four groups.

CONCLUSION

Administration of the oral Punica granatum flower extract was associated with a decreased quantity and quality of the adhesions in the animal model of rat in this study. This therapy might be an effective and safe strategy to reduce intraperitoneal adhesion after abdominal surgeries in animal models.

The Variable Regulatory Effect of Arsenic on Nrf2 Signaling Pathway in Mouse: a Systematic Review and Meta-analysis

Arsenic is known to cause oxidative damage. Nuclear factor E2-relate factor-2 (Nrf2) can resist this toxicity. Scholars demonstrated that Nrf2 pathway was activated by arsenic. In contrast, other articles established arsenic-induced inhibition of Nrf2 pathway. To resolve the contradiction and elucidate the mechanism of Nrf2 induced by arsenic, 39 publications involving mouse models were identified through exhaustive database retrieval and were analyzed. The pooled results suggested that arsenic obviously elevated transcription and translation levels of Nrf2 and its downstream genes, NAD(P)H dehydrogenase 1 (NQO1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC), and GST-glutathione-S-transferase1/2 (GSTO1/2). Arsenic increased the level of reactive oxygen species (ROS), but reduced the level of glutathione (GSH). Subgroup analysis between arsenic and control groups showed that the levels of Nrf2 and its downstream genes are greater in high dose than that in the low dose, higher in short-term exposure than long term, female subjects tolerated better than males, higher in mice than the rats, and greater in other organs than the liver. However, the contents of genes of Nrf2 pathway between the arsenic and control groups were lower in rats than in mice and were less for long-term exposure than the short term (P < 0.05). Conclusively, a variable regulation of arsenic on Nrf2 pathway is noted. Higher dose and short-term exposure of female mice organs except for liver promoted Nrf2 pathway. On the other hand, arsenic inhibited Nrf2 pathway for long-term exposure on rats.

Biochemical investigation of association of arsenic exposure with risk factors of diabetes mellitus in Pakistani population and its validation in animal model

Arsenic is one of the naturally occurring heavy metal that has been reported to cause damaging effects on different body organs. This study was aimed to determine the arsenic level in different water sources and investigate the effect of arsenic exposure on risk factors of diabetes mellitus (DM) in human participants and experimental animals. We recruited 150 participants to investigate the arsenic exposure in their urine and from drinking water. We found that males contained significantly higher (P < 0.001) concentrations of urinary arsenic as compared with that of their female counterparts. Similarly, urinary arsenic concentration was high and showed significant association in the age of ≥ 60 years (P < 0.05), illiterate (P < 0.001), smokers (P < 0.0001), and diabetic (P < 0.0001) participants. Moreover, urinary arsenic exposure was also associated with higher levels of fasting (P < 0.001) and random blood glucose (P < 0.001), HbA1c (P < 0.001), AST, ALT, MDA, IL-6, CRP, blood urea nitrogen, and creatinine in arsenic-exposed diabetics as compared with that of unexposed diabetics. Further, we also exposed the white albino rats with arsenic in drinking water for 30 days and their blood glucose was measured at 15th and 30th days of treatment that was significantly higher (P < 0.001) in arsenic-exposed animals as compared with that of unexposed animals. Similarly, arsenic-exposed animals failed to tolerate exogenously administered glucose (P < 0.001) as compared with that of unexposed animals. Likewise, insulin and glutathione concentrations were also significantly decreased (P < 0.001) in arsenic-exposed animals as compared with that of unexposed animals. The alterations in normal values of glucose, insulin, and glutathione exhibited the damaging effects of arsenic exposure in experimental rats. This study showed that arsenic exposed to human beings and animals through drinking water resulted in the disruption of pancreatic β-cell functioning that provoked the risk factor for development of DM. This study also suggested that long-term arsenic exposure induces hyperglycemia, inflammation, and oxidative stress that may lead to the onset of development of DM.

Advanced oxidation protein products play critical roles in liver diseases

There is a complex oxidant and antioxidant system that maintains the redox homoeostasis in the liver. While suffering from exogenous or endogenous risk factors, the balance between oxidants and antioxidants is disturbed and excessive reactive oxygen species are generated, resulting in oxidative stress. Oxidative stress is prevalent in various liver diseases and is thought to be involved in their pathophysiology. Advanced oxidation protein products are generated under conditions of oxidative damage and are newly described protein markers of oxidative stress. Previous studies have underscored the universal pathogenic roles of oxidation protein products in various diseases. However, investigations into how these products participate in the development of liver diseases have been superficial and insufficient. In this review, we highlight the current understanding of the roles of advanced oxidation protein products in liver disease pathogenesis and the underlying mechanisms. Moreover, we summarize the current studies on advanced oxidation protein products in infectious and noninfectious, acute and chronic liver diseases. Different strategies for targeting these advanced oxidation protein products and future perspectives, which may pave the way for developing new therapeutic strategies, will also be discussed here.

Selenium Nanoparticles Dispersed in Phytochemical Exert Anti-Inflammatory Activity by Modulating Catalase, GPx1, and COX-2 Gene Expression in a Rheumatoid Arthritis Rat Model

BACKGROUND Literature shows that serum selenium concentration is low in rheumatoid arthritis (RA) patients. Biochemical properties of nanoparticles (NPs) are depend in its medium dispersed. Biochemical properties could effectively alter the therapeutic potential of NPs. Phytochemicals could serve as suitable medium for dispersion of NPs. P-Coumaric acid (CA) known to have anti-inflammatory activity. MATERIAL AND METHODS In the present experiment, we investigated the anti-inflammatory effect of SeNPs dispersed in 1% CA against Complete Freund's adjuvant induced RA. Celecoxib was used as a reference drug. RESULTS Selenium NPs (SeNPs) size is maintained in 1% CA solution. We observed that supplementation with 500 μg/Kg body weight (b.w.) eNPs significantly restored the levels of thiobarbituric acid reactive substances, COX-2 activity, different antioxidant enzyme activities, and inflammatory cytokines (TNF-α, IL-1β, IL-6, and MCP-1) in RA rats. The mRNA expression of antioxidant enzymes such as MnSOD, Cu/ZnSOD, ECSOD, CAT, and GPx1 was found to be downregulated, whereas COX-2 was upregulated in RA rats; however, the mRNA expression of CAT, GPx1, and COX-2 reverted back to near normal levels in SeNPs-treated animals. CONCLUSIONS The therapeutic potential of SeNPs was confirmed through histological observation of angle joints in different experimental animals. Our results collectively suggest that SeNPs dispersed in CA can be an effective therapeutic agent for inflammatory disorders like acute gouty arthritis.

Proanthocyanidins Antagonize Arsenic-Induced Oxidative Damage and Promote Arsenic Methylation through Activation of the Nrf2 Signaling Pathway

Purpose

To investigate the effects of grape seed proanthocyanidin extract (GSPE) on oxidative damage and arsenic (As) methylation and to clarify the role of Nrf2 in the process.

Methods

L-02 cells were treated with arsenic (25 μM) and GSPE (10, 25, and 50 mg/L) for 24 h. Cell viability was analyzed by MTT assay. Cell apoptosis and ROS fluorescence were detected by flow cytometry. Oxidative stress marker levels were measured using commercial kits. mRNA and protein expression were detected by qRT-PCR and western blotting. The cellular concentrations of methylation products were measured by HPLC-HGAFS. Arsenic methylation ability of cells was determined.

Results

Cell survival rate was significantly lower in the As group than in the control group (P < 0.05), while cell apoptosis increased and the number of apoptotic cells decreased gradually after GSPE intervention. Superoxide dismutase, glutathione, and sulfhydryl levels in the intervention group were significantly higher (P < 0.05), while MDA and ROS levels were significantly lower (P < 0.05) than those in the As group. The mRNA and protein expression of Nrf2, HO-1, NQO1, and glutathione-S-transferase increased in the As + GSPE group compared with that in the As group (P < 0.05). GSPE significantly increased methylated As level, primary methylation index, secondary methylation index, average growth rate of methylation, and average methylation speed compared with the GSPE untreated group (P < 0.05). After Nrf2 inhibition, the effect of GSPE decreased significantly.

Conclusion

GSPE activates the Nrf2 signaling pathway to antagonize As-induced oxidative damage and to promote As methylation metabolism. Therefore, GSPE may be a potential agent for relieving As-induced hepatotoxicity.

Prominence of Oxidative Stress in the Management of Anti-tuberculosis Drugs Related Hepatotoxicity

Advanced medical services and treatments are available for treating Tuberculosis. Related prevalence has increased in recent times. Unfortunately, the continuous consumption of related drugs is also known for inducing hepatotoxicity which is a critical condition and cannot be overlooked. The present review article has focused on the pathways causing these toxicities and also the role of enzyme CYP2E1, hepatic glutathione, Nrf2-ARE signaling pathway, and Membrane Permeability Transition as possible targets which may help in preventing the hepatotoxicity induced by the drugs used in the treatment of tuberculosis.

Boron ameliorates arsenic-induced DNA damage, proinflammatory cytokine gene expressions, oxidant/antioxidant status, and biochemical parameters in rats

Arsenic, an element found in nature, causes hazardous effects on living organisms. Meanwhile, natural compounds exhibit protective effects against hazardous substances. This study evaluated the effects of boron against arsenic-induced genotoxicity and altered biochemical parameters in rats. Thirty-five male Wistar albino rats were equally divided into five groups, and the experimental period lasted 30 days. One group was used as the control, and another group was treated with 100 mg/L arsenic in drinking water. The other groups were orally treated with 5, 10, and 20 mg/kg boron plus arsenic (100 mg/L via drinking water). Arsenic caused changes in biochemical parameters, total oxidant/antioxidant status, and DNA damage in mononuclear leukocytes. Moreover, it increased IFN-γ, IL-1β, TNF-α, and NFκB mRNA expression levels in rat tissue. However, boron treatment improved arsenic-induced alterations in biochemical parameters and increases in DNA damage and proinflammatory cytokine gene expressions.

Effects of Olive Oil supplementation on Sodium Arsenate-induced Hepatotoxicity in Mice

Background:

Sodium arsenate (As), a toxic substance with induced oxidative stress, lead to hepatotoxicity. Olive oil (OO) with antioxidant property has protective effect on toxicity. The aim of this study was to investigate protective effect of OO on sodium As-induced hepatotoxicity in mice.

Subjects and Methods:

In this experimental study, 32 adult male BALB/c mice were divided randomly into four groups: control group (received only normal saline, the same volume as other groups), OO (0.4 mL/day, gavage), sodium As (15 mg/kg, gavage), and OO + sodium As (received OO 1 h before sodium As). Drugs were given for 30 consecutive days. After the last receipt of the drugs, oxidative stress parameters [malondialdehyde (MDA), glutathione (GSH)] in tissue, liver function parameters [alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP)] in serum, ferric reducing ability of plasma (FRAP) in plasma, and histopathological assays were performed.

Results:

Sodium As induced hepatic injury as indicated by significant increase in AST, ALT, ALP, and LDH in serum and pathologic evidences. It also induces hepatic oxidative stress biomarkers as indicated by significant increase in levels of MDA and significant decrease in FRAP and GSH concentration. OO administration significantly improved oxidative stress parameters, histopathological changes, and enzymatic markers of liver injury.

Conclusions:

It was concluded that antioxidant activity of OO has hepatoprotective effect on As-induced hepatic injury.

Combination of Selenomethionine and N-Acetylcysteine Alleviates the Joint Toxicities of Aflatoxin B1 and Ochratoxin A by ERK MAPK Signal Pathway in Porcine Alveolar Macrophages

Our previous studies showed that aflatoxin B1 (AFB1) and ochratoxin A (OTA) could trigger joint immune toxicity. Little is known about the combined effects of selenomethionine (SeMet) and N-acetylcysteine (NAC) on the joint toxicities of the two toxins. In this study, results showed that SeMet or NAC alone or in combination significantly alleviated the downswing of cell viability, glutathione production, and phagorytosis induced by AFB1 and OTA in porcine alveolar macrophages. The uptrend of lactate dehydrogenase activities, apoptosis, reactive oxygen species levels, and the relative mRNA of inflammatory cytokines triggered by the two toxins was decreased. Combination of them was more effective than single application. Knockdown of p38, c-JUN N-terminal kinase (JNK), or extracellular signal-regulated kinase (ERK) via use of the corresponding specific siRNA could alleviate the joint toxicities of AFB1 and OTA. However, the ERK but not p38 or JNK pathway was involved in the protection of SeMet and NAC against the immunotoxicity. In conclusion, combination of SeMet and NAC might be a new therapeutic orientation for preventing the joint toxicities induced by AFB1 and OTA.

Nutritional management can assist a significant role in alleviation of arsenicosis

Consumption of arsenic contaminated water causes serious skin disease and cancer in a significant number of exposed people. Chelating agents, consider an expensive therapy, are employed in the treatment of arsenic intoxication. There are reports which suggest that the poorest suffer the most from arsenicosis. This may be due to improper diet intake, consist of low protein and micronutrients which increase the vulnerability to arsenic-related disorders. Several human studies demonstrated the associations between malnourishment and the development of arsenic-caused skin lesions, skin cancer and cardiovascular effects. Thus, there is an urgent need of implementation of mitigation strategies for improving the health of exposed populations. Nutrition enhances the detoxification process so food rich in vitamins, protein, antioxidants help in its detoxification process. Methylation is the detoxification process which takes place via S-adenosylmethionine (SAM). It is a methyl group donor and it derived its methyl group from diet. Nutritional intervention thus may appear as a practical and inexpensive approach. Nutrition provides protection from toxic effect of arsenic by two ways (i) methylation of As (ii) antioxidants which provides protection against free radical species. The governments and NGOs may run awareness programmes in arsenic affected area regarding prevention and alternate therapy which can decrease the susceptibility of the exposed population. They could also help in distributing cheaper, high protein diets particularly to the masses who cannot afford such foods. Thus, to prevent arsenicosis alternate therapy and proper nutrition could be the important strategy for alleviating its toxic effects. This mini review provides an insight on the importance of nutrition in preventing adverse effect cause by arsenic to suffer population.

Levels of plasma selenium and urinary total arsenic interact to affect the risk for prostate cancer

This study investigated whether plasma selenium levels modified the risk for prostate cancer (PC) related to arsenic exposure. We conducted a case-control study that included 318 PC patients and 318 age-matched, healthy control subjects. Urinary arsenic profiles were examined using HPLC-HG-AAS and plasma selenium levels were measured by ICP-MS. We found that plasma selenium levels displayed a significant dose-dependent inverse association with PC. The odds ratio (OR) and 95% confidence interval (CI) for PC was 0.07 (0.04-0.13) among participants with a plasma selenium level >28.06 μg/dL vs. ≤19.13 μg/dL. A multivariate analysis showed that participants with a urinary total arsenic concentration >29.28 μg/L had a significantly higher OR (1.75, 1.06-2.89) for PC than participants with ≤29.89 μg/L. The combined presence of a low plasma selenium level and a high urinary total arsenic concentration exponentially increased the OR for PC, and additively interacted with PSA at levels ≥20 ng/mL. This is the first epidemiological study to examine the combined effects of plasma selenium and urinary total arsenic levels on the OR for PC. Our data suggest a low plasma selenium level coupled with a high urinary total arsenic concentration creates a significant risk for aggressive PC.

Biological effects and epidemiological consequences of arsenic exposure, and reagents that can ameliorate arsenic damage in vivo

Through contaminated diet, water, and other forms of environmental exposure, arsenic affects human health. There are many U.S. and worldwide "hot spots" where the arsenic level in public water exceeds the maximum exposure limit. The biological effects of chronic arsenic exposure include generation of reactive oxygen species (ROS), leading to oxidative stress and DNA damage, epigenetic DNA modification, induction of genomic instability, and inflammation and immunomodulation, all of which can initiate carcinogenesis. High arsenic exposure is epidemiologically associated with skin, lung, bladder, liver, kidney and pancreatic cancer, and cardiovascular, neuronal, and other diseases. This review briefly summarizes the biological effects of arsenic exposure and epidemiological cancer studies worldwide, and provides an overview for emerging rodent-based studies of reagents that can ameliorate the effects of arsenic exposure in vivo. These reagents may be translated to human populations for disease prevention. We propose the importance of developing a biomarker-based precision prevention approach for the health issues associated with arsenic exposure that affects millions of people worldwide.

Oxidative Damage Induced by Arsenic in Mice or Rats: A Systematic Review and Meta-Analysis

In this meta-analysis, studies reporting arsenic-induced oxidative damage in mouse models were systematically evaluated to provide a scientific understanding of oxidative stress mechanisms associated with arsenic poisoning. Fifty-eight relevant peer-reviewed publications were identified through exhaustive database searching. Oxidative stress indexes assessed included superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), glutathione-s-transferase (GST), glutathione reductase (GR), oxidized glutathione (GSSG), malondialdehyde (MDA), and reactive oxygen species (ROS). Our meta-analysis showed that arsenic exposure generally suppressed measured levels of the antioxidants, SOD, CAT, GSH, GPx, GST, and GR, but increased levels of the oxidants, GSSG, MDA, and ROS. Arsenic valence was important and GR and MDA levels increased to a significantly (P < 0.05) greater extent upon exposure to As³⁺ than to As⁵⁺. Other factors that contributed to a greater overall oxidative effect from arsenic exposure included intervention time, intervention method, dosage, age of animals, and the sample source from which the indexes were estimated. Our meta-analysis effectively summarized a wide range of studies and detected a positive relationship between arsenic exposure and oxidative damage. These data provide a scientific basis for the prevention and treatment of arsenic poisoning.

Alleviation of lead-induced oxidative stress and immune damage by selenium in chicken bursa of Fabricius

We investigated lead (Pb)-induced oxidative stress and immune damage in the chicken bursa of Fabricius (BF) and the ameliorative effect of selenium (Se). Seven-day-old male chickens were randomly divided into four groups and were provided standard diet and drinking water, Na₂SeO₃ added to the standard diet and drinking water, standard diet and (CH₃COO)₂Pb added to drinking water, and Na₂SeO₃ added to the standard diet and (CH₃COO)₂Pb added to drinking water for 30, 60, and 90 days. The presence of Pb inhibited total antioxidant capacity (T-AOC), glutathione peroxidase (GPx), glutathione S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT) activities; decreased glutathione (GSH) content; increased malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) contents; inhibited interleukin (IL)-2 and interferon-γ (IFN-γ) messenger RNA (mRNA) expression; and increased IL-4, IL-6, IL-10, IL-12β, and IL-17 mRNA expression. The presence of Se relieved all of the above Pb-induced changes. There were close correlations among GSH, CAT, T-AOC, SOD, GPx, MDA, and H₂O₂ and among IL-2, IL-4, IL-6, IL-12β, IL-17, and IFN-γ. Our data showed that Pb caused oxidative stress and immune damage in the chicken BF. Se alleviated Pb-induced oxidative stress and immune damage in the chicken BF.

Prophylactic effects of pomegranate (Punica granatum) juice on sodium fluoride induced oxidative damage in liver and erythrocytes of rats

The objective of this study was to investigate the protective effects of pomegranate (Punica granatum) juice (PGJ) on oxidative damages in liver tissue and erythrocytes of rats intoxicated by sodium fluoride (NaF). Rats were randomly divided into two groups: group I received standard diet and group II received orally 1 mL of PGJ. After 5 weeks of pretreatment, each group was divided again into two subgroups and treated for another 3 weeks as follows: group I was subdivided into a control group and a group that was treated with 100 ppm of NaF (in drinking water); group II was subdivided into one group that was treated daily with both 100 ppm NaF and PGJ (1 mL orally) and one that received daily 1 mL of pomegranate juice. Exposure to NaF decreased hematological parameters, changed the total protein, albumin, bilirubin levels, and increased the activities of hepatic marker enzymes. We also noted an increase in lipid peroxidation contents, accompanied by a decrease of reduced glutathione levels. Antioxidant enzyme activities in both tissues were modified in the NaF group compared with the control group. However, the administration of PGJ juice caused an amelioration of the previous parameters. Our results indicated the potential effects of NaF to induce oxidative damage in tissues and the ability of PGJ to attenuate NaF-induced oxidative injury.

Antioxidant and anti-inflammatory potential of pomegranate rind extract to ameliorate cisplatin-induced acute kidney injury

The aim of the present study was to evaluate the nephroprotective effect of pomegranate in cisplatin-induced acute kidney injury.