Arsenic-induced oxidative stress, cholinesterase activity in the brain of Swiss albino mice, and its amelioration by antioxidants Vitamin E and Coenzyme Q10

Morin attenuates arsenic-induced toxicity in 3T3 embryonic fibroblast cells by suppressing oxidative stress, inflammation, and apoptosis: In vitro and silico evaluations

This study aims to investigate the curative effects of Morin, a flavonoid, against arsenic toxicity in 3T3 embryonic fibroblast cells and its effect on the molecular mechanisms of cells. The cytotoxicity and viability of the cells were measured by MTT and LDH tests. Arsenic (0.74 μM) was used to trigger toxicity and Morin (50 μM) was used for treatment. The levels of oxidative stress biomarkers and the activities of antioxidant enzymes were measured by spectrophotometric method, and inflammatory markers were measured by ELISA method. While mRNA expression levels of Bax, Bcl-2 levels, and Caspase-3 activity were measured by qRT-PCR technique, TUNEL staining was performed to detect DNA breaks and DAPI staining to visualize nuclear changes. Protein structures were retrieved from the protein data bank. OpenBabel and Autodock programs were used for the molecular docking study. Morin rescued the 3T3 embryonic fibroblast cells exposed to arsenic. However, Arsenic decreased the activities of antioxidant enzymes in cells and significantly increased oxidative stress, inflammation, and apoptosis. Morin treatment reduced oxidative damage and TNF-α and IL-1β levels. Arsenic-induced Caspase-3 mRNA expression level and Bax protein mRNA expression level were significantly increased, while Bcl-2 mRNA expression level was significantly decreased. While Caspase-3 mRNA expression level and Bax protein mRNA expression level decreased with morin treatment, Bcl-2 mRNA expression level increased significantly. Molecular docking study results showed good binding affinity of morin in SOD, GSH-Px, Bax, Bcl-2, Caspase-3, TNF-α, and IL-1β structures. Morin showed antioxidant, anti-inflammatory, and anti-apoptotic effects against Arsenic-induced cellular toxicity.

Anti-oxidant activity of coenzyme Q10 against AlCl3/D-galactose in albino rat induced cognitive dysfunctions: Behavioral, biochemical, and BACE-1/GSK-3β alterations

The relationship between amyloid beta (Aβ) and oxidative stress (OS), both prominent factors in Alzheimer's disease-related neural degeneration, is deeply interconnected. The cleavage of the extracellular domain of Amyloid precursor protein (APP) and phosphorylating different substrates, respectively, the β-site amyloid precursor protein cleaving enzyme-1 (BACE-1) and Glycogen synthase kinase-3-beta (GSK-3β) enzymes initiate the synthesis of Aβ, which causes cognitive deficits in AD. This study aimed to explore the protective potential of Coenzyme Q10 (CoQ10). It also sought to uncover any synergistic effects when combined with donepezil, an acetylcholinesterase inhibitor, in treating Alzheimer's disease in male albino rats, focusing on the modulation of the BACE-1/GSK-3β pathway. The experiment involved 70 rats categorized into different groups: control, donepezil alone, CoQ10 alone, AD-model, donepezil co-treatment, CoQ10 co-treatment, and CoQ10 + donepezil combination. Various assessments, such as cholinesterase activity, oxidative stress, serum iron profile, Brain Derived Neurotrophic Factor (BDNF), Tau protein, β-site amyloid precursor protein cleaving enzyme-1 (BACE-1), phosphatase and tensin homolog (Pten), and Glycogen synthase kinase-3-beta (GSK-3β), were conducted on behavioral and biochemical aspects. CoQ10 treatment demonstrated memory improvement, enhanced locomotion, and increased neuronal differentiation, mainly through the inhibition of the dual BACE-1/GSK-3β. These findings were substantiated by histological and immunohistological examinations of the hippocampus.

Developmental exposure to arsenic reduces anxiety levels and leads to a depressive-like behavior in female offspring rats: Molecular changes in the prefrontal cortex

Exposure to inorganic arsenic (iAs) detrimentally affects the structure and function of the central nervous system. In-utero and postnatal exposure to iAs has been connected to adverse effects on cognitive development. Therefore, this investigation explores neurobehavioral and neurochemical effects of 0.05 and 0.10 mg/L iAs exposure during gestation and lactation periods on 90-day-old female offspring rats. The assessment of anxiety- and depressive-like behaviors was conducted through the application of an elevated plus maze and a forced swim test. The neurochemical changes were evaluated in the prefrontal cortex (PFC) through the determination of enzyme activities and α1 GABAA subunit expression levels. Our findings revealed a notable impact of iAs exposure on anxiety and the induction of depressive-like behavior in 90-day-old female offspring. Furthermore, the antioxidant status within the PFC exhibited discernible alterations in exposed rats. Notably, the activities of acetylcholinesterase and glutamate pyruvate transaminase demonstrated an increase, while glutamate oxaloacetate transaminase activity displayed a decrease within the PFC due to the iAs treatment. Additionally, a distinct downregulation in the mRNA expression of the α1GABAA receptor was observed in this neuronal region. These findings strongly suggest that iAs exposure during early stages of rat development causes significant modifications in brain oxidative stress markers and perturbs the activity of enzymes associated with cholinergic and glutamatergic systems. In parallel, it elicits a discernible reduction in the level of GABA receptors within the PFC. These molecular alterations may play a role in the diminished anxiety levels and the depressive-like behavior outlined in the current investigation.

AuNPs with Cynara scolymus leaf extracts rescue arsenic-induced neurobehavioral deficits and hippocampal tissue toxicity in Balb/c mice through D1R and D2R activation

The present study was designed to evaluate whether AuNPs (gold nanoparticles) synthesized with the Cynara scolymus (CS) leaf exert protective and/or alleviative effects on arsenic (As)-induced hippocampal neurotoxicity in mice. Neurotoxicity in mice was developed by orally treating 10 mg/kg/day sodium arsenite (NaAsO2) for 21 days. 10 µg/g AuNPs, 1.6 g/kg CS, and 10 µg/g CS-AuNPs were administered orally simultaneously with 10 mg/kg As. CS and CS-AuNPs treatments showed down-regulation of TNF-α and IL-1β levels. CS and CS-AuNPs also ameliorated apoptosis and reduced the alterations in the expression levels of D1 and D2 dopamine receptors induced by As. Simultaneous treatment with CS and CS-AuNPs improved As-induced learning, memory deficits, and motor coordination in mice assessed by water maze and locomotor tests, respectively. The results of this study provide evidence that CS-AuNPs demonstrated neuroprotective roles with antioxidant, anti-inflammatory, and anti-apoptotic effects, as well as improving D1 and D2 signaling, and eventually reversed neurobehavioral impairments.

Vitamin E and conflicting understandings in noncommunicable diseases: Is it worth supplementing?

Vitamin E is a lipid-soluble nutrient found mainly in vegetable oils and oilseeds. It is divided into eight homologous compounds; however, only α-tocopherol exhibits vitamin activity. Many advantages are related to these compounds, including cellular protection through antioxidant and anti-inflammatory activity, and improving lipid metabolism. Physiopathology of many diseases incepts with reduced antioxidant defense, characterized by an increased reactive oxygen species production and activation of transcription factors involved in inflammation, such as nuclear factor-kappa B (NF-κB), that can be linked to oxidative stress. Moreover, disorders of lipid metabolism can increase the risk of cardiovascular diseases. In addition, intestinal dysbiosis plays a vital role in developing chronic non-communicable diseases. In this regard, vitamin E can be considered to mitigate those disorders, but data still needs to be more conclusive. This narrative review aims to elucidate the mechanisms of action of vitamin E and if supplementation can be beneficial in a disease scenario regarding non-communicable diseases.

Efficacy of coenzyme Q10 and curcumin on antioxidant enzyme activity and hippocampal alteration following exposure to cyclophosphamide in male rat

Coenzyme Q10 (KQ10) and curcumin (KUR) supplements are extensively used for their potential antioxidant, anticancer, and antiapoptotic properties. The present study investigated the neuroprotective potential of KQ10 and KUR against the side effect of cyclophosphamide (SF) (150 mg/kg) on the hippocampus of male Wistar albino rats. Forty-nine 10-12 weeks old rats were randomly divided into seven groups: control, olive oil (OL), SF, KQ10, KUR, SF+KQ10, and SF+KUR. Our biochemical finding showed a significant decrease in superoxide dismutase (SOD) level in the SF group compared to the control group (p < 0.05). There was also a significant reduction in the total number of the hippocampal pyramidal neurons in the CA1, CA2, and CA1-3 regions in the SF group compared to the control group (p < 0.05). In the SF+KQ10 group, we found a significant increase in serum SOD level and the total number of the hippocampal pyramidal neurons in the CA1, CA2, and CA1-3 regions compared to the SF group (p < 0.05). Immunohistochemical and histopathological examination exhibited noteworthy findings in the hippocampus tissues. Our findings showed that KQ10 administration significantly mitigated the hippocampal alteration caused by SF through enhancing antioxidant enzyme activity and reducing apoptosis. However, we found no protective activity of KUR on the hippocampus tissue, which may be due to its weak antioxidative activity.

Fisetin attenuates arsenic and fluoride subacute co-exposure induced neurotoxicity via regulating TNF-α mediated activation of NLRP3 inflammasome

Groundwater is considered safe, however, the occurrence of contaminants like arsenic and fluoride has raised a major healthcare concern. Clinical studies suggested that arsenic and fluoride co-exposure induced neurotoxicity, however efforts to explore safe and effective management of such neurotoxicity are limited. Therefore, we investigated the ameliorative effect of Fisetin against arsenic and fluoride subacute co-exposure-induced neurotoxicity, and associated biochemical and molecular changes. Male BALB/c mice Arsenic (NaAsO₂: 50mg/L) and fluoride (NaF: 50mg/L) were exposed to drinking water and fisetin (5, 10, and 20mg/kg/day) was administered orally for 28 days. The neurobehavioral changes were recorded in the open field, rotarod, grip strength, tail suspension, forced swim, and novel object recognition test. The co-exposure resulted in anxiety-like behaviour, loss of motor coordination, depression-like behaviour, and loss of novelty-based memory, along with enhanced prooxidant, inflammatory markers and loss of cortical and hippocampal neurons. The treatment with fisetin reversed the co-exposure-induced neurobehavioral deficit along with restoration of redox & inflammatory milieu, and cortical and hippocampal neuronal density. Apart from antioxidants, inhibition of TNF-α/ NLRP3 expression has been suggested as one of the plausible neuroprotective mechanisms of Fisetin in this study.

In utero arsenic exposure and early childhood motor development in the New Hampshire Birth Cohort Study

Introduction

High-level prenatal and childhood arsenic (As) exposure characteristic of several regions in Asia (e.g., Bangladesh), may impact motor function. However, the relationship between lower-level arsenic exposure (characteristic of other regions) and motor development is largely unstudied, despite the potential for deficient motor skills in childhood to have adverse long-term consequences. Thus, we sought to investigate the association between prenatal As exposure and motor function among 395 children in the New Hampshire Birth Cohort Study, a rural cohort from northern New England.

Methods

Prenatal exposure was estimated by measuring maternal urine speciated As at 24-28 weeks of gestation using high-performance liquid chromatography (HPLC) inductively coupled plasma mass spectrometry (ICP-MS) and summing inorganic As, monomethylarsonic acid, and dimethylarsinic acid to obtain total urinary As (tAs). Motor function was assessed with the Bruininks-Oseretsky Test of Motor Proficiency, 2nd Edition (BOT-2) at a mean (SD) age of 5.5 (0.4) years.

Results

Children who completed this exam were largely reported as white race (97%), born to married mothers (86%) with a college degree or higher (67%). The median (IQR) gestational urine tAs concentration was 4.0 (5.0) µg/L. Mean (SD) BOT-2 scores were 48.6 (8.4) for overall motor proficiency and 48.2 (9.6) for fine manual control [standard score = 50 (10)], and were 16.3 (5.1) for fine motor integration and 12.5 (4.1) for fine motor precision [standard score = 15 (5)]. We found evidence of a non-linear dose response relationship and used a change-point model to assess the association of tAs with overall motor proficiency and indices of fine motor integration, fine motor precision, and their composite, fine manual control, adjusted for age and sex. In models adjusted for potential confounders, each doubling of urine tAs decreased overall motor proficiency by -3.3 points (95% CI: -6.1, -0.4) for tAs concentrations greater than the change point of 9.5 µg/L and decreased fine motor integration by -4.3 points (95% CI: -8.0, -0.6) for tAs concentrations greater than the change point of 17.0 µg/L.

Discussion

In summary, we found that levels of prenatal As exposure above an empirically-derived threshold (i.e., the change point) were associated with decrements in childhood motor development in a US population.

Coenzyme Q10 treatment and diazinon exposure in parental male rats: effects of the exposure on their neonatal brains

Prenatal acute and chronic exposure to organophosphorus pesticides may evoke physical and behavioral impairments in offspring development. However, the mechanism of antioxidant consumption repair to cure these impairments remains unclear. This study aimed to investigate the protective effects of COQ10 against DZN toxicity by measuring Malondialdehyde (MDA) level, superoxide dismutase (SOD) activity, the expression of MH2A, DNMT1, H2AZ, and HDAC3, and the histopathology in the brain of neonatal Wistar albino rats whose male parents were exposed to DZN and COQ10. The results showed that COQ10 could significantly decrease MDA level, histopathological alteration, and expression of DNMT1 and HDAC3 in the neonatal brain (P < 0.05). Also, an increase in SOD activity and expression of MH2A and H2AZ were observed in the neonatal brain of this group (P < 0.05). These investigations suggest that COQ10 can reduce the effects of DZN on neuronal oxidative stress and its damage to the neonatal brain.

Oxidative stress and toxicity produced by arsenic and chromium in broiler chicks and application of vitamin E and bentonite as ameliorating agents

The present study investigated the adverse effects of arsenic and chromium in broilers and ascertained the role of vitamin E and bentonite in alleviating their harmful effects. For this purpose, we experimented on 180 one-day-old broiler chickens. The feed was administered to broiler chicks of groups 2, 6, 7, 8, and 9 chromium @ (270 mg.kg−1 BW). Groups 3, 6, 7, 8, and 9 were administered arsenic @ (50 mg.kg−1 BW). Groups 4, 7, and 9 received vitamin E (150 mg.kg−1 BW), and groups 5, 8, and 9 received bentonite (5%), respectively. Group 1 was kept in control. All the broiler chicks treated with chromium and arsenic showed a significant (p &lt; 0.05) decline in erythrocytic parameters on experimental days 21 and 42. Total proteins decreased significantly, while ALT, AST, urea, and creatinine increased significantly (p &lt; 0.05). TAC and CAT decreased significantly (p &lt; 0.05), while TOC and MDA concentrations increased significantly (p &lt; 0.05) in chromium and arsenic-treated groups on experimental days 21 and 42. Pearson correlation analysis revealed a strong positive correlation between TAC and CAT (Pearson correlation value = 0.961; p &lt; 0.001), similarly TOC and MDA positive correlation (Pearson correlation value = 0.920; p &lt; 0.001). However, TAC and CAT showed a negative correlation between TOC and MDA. The intensity of gross and microscopic lesions was more in chromium (270 mg.kg−1) and arsenic (50 mg.kg−1) singly or in combination-treated groups. Thus, broiler chicks treated with chromium plus arsenic exhibited higher gross and microscopic lesion intensity than other treated groups. Fatty degeneration, severe cytoplasmic vacuolar degeneration, and expansion of sinusoidal spaces were the main lesions observed in the liver. Kidneys showed renal epithelial cells necrosis, glomerular shrinkage, and severe cytoplasmic vacuolar degeneration. Co-administration of bentonite along with chromium and arsenic resulted in partial amelioration (group 8) compared to groups 7 and 9, administered arsenic + chromium + vitamin E and arsenic + chromium + vitamin E + bentonite, respectively. It was concluded that arsenic and chromium cause damage not only to haemato-biochemical parameters but also lead to oxidation stress in broilers. Vitamin E and bentonite administration can ameliorate toxicity and oxidative stress produced by arsenic and chromium.

Short-term trivalent arsenic and hexavalent chromium exposures induce gut dysbiosis and transcriptional alteration in adipose tissue of mice

BACKGROUND

Inorganic arsenic [As(III)] and hexavalent chromium [Cr(VI)] can potentially affect metabolic functions. These heavy metal(s)/metalloids can also affect the gut microbial architecture which affects metabolic health. Here, we assessed the effects of short-term exposure of As(III) and Cr(VI) on key transcription factors in adipose tissues and on selected gut microbial abundances to understand the possible modulatory role of these toxicants on host metabolic health.

METHODS AND RESULTS

qRT-PCR based relative bacterial abundance studies in cecal samples, gene expression analysis for gut wall integrity in ileum and colon and adipogenesis, lipolysis, and thermogenic genes in gonadal white and brown adipose tissue (gWAT and BAT), along with tissue oxidative stress parameters have been performed. As(III) and Cr(VI) exposure reduced beneficial Lactobacilli, Bifidobacteria, Akkermansia, Lachenospiraceae, Fecalibacterium, Eubacterium, and clostridium coccoid group while increasing lipopolysaccharides producing Enterobacteriaceae abundances. It also impaired structural features and expression of key tight junction and mucin production genes in ileum and colon (Cld-2, Cld-4, ZO-1, ZO-2, MUC-2 and - 4). In gWAT it inhibited adipogenesis (PPARγ, FASN, SREBP1a), lipolysis (HSL, ACOX-1), and thermogenesis (UCP-1, PGC1a, PRDM-16, PPARa) related genes expression, whereas in BAT, it enhanced adipogenesis and reduced thermogenesis. These exposures also reduces the endogenous antioxidants levels in these tissues and promote pro-inflammatory cytokines genes expression (TLRs, IL-6, MCP-1). The combinatorial exposure appears to have more deleterious effects.

CONCLUSION

These effects of As(III) and Cr(VI) may not directly be linked to their known toxicological effects, instead, more intriguing crosstalk with gut microbial ecosystem hold the key.

Ameliorative effect of Brassica oleracea var. Italica extract on oxidative damage of arsenic in the rat's brain: biochemical, pathological, and behavioral aspects

Brain damage caused by the metal accumulation may result in the permanent injuries including severe neurological disorders. Thus, the aim of this study was to determine the medicinal efficacy of broccoli extract in arsenic-induced brain poisoning. Twenty-eight female rats were classified into 4 groups; control, receiving sodium arsenate (As), As + broccoli extract (As + Bc), and (Bc). Then, the Elevated Plus-Maze and pathological-biochemical assessment of the brain tissue were performed. Moreover, the GC-MS was used to explore the quantity and quality of broccoli extract. The catalase had a significant decrease in the As group compared to that of the control group; As + Bc and Bc groups also showed a significant increase compared to that of the As group. Glutathione peroxidase was the lowest in the As group (1.84 ± 0.97) and the highest in the Bc group (5.51 ± 2.31). The Treatment significantly reduced pro-inflammatory cytokines in the As + Bc group. In addition, in terms of behavioral changes, the duration of presence in the open arm was reduced in the As group compared to that of the control group. Besides, the open arm duration increased significantly in the Bc group. Interestingly, there was a significant increase in estrogen and gonadotropin hormones in the Bc group compared to the other groups. Pathological findings showed that the condition of cortical neurons was improved and the surrounding space was reduced in As + Bc compared to that of the As group. In addition, more than 30% of the extract's compounds are made up Phytol,1-isothiocyanate-4-[methylsulfinyl] butane, and γ-Sitosterol. Thereby, the broccoli extract with active substances was highly effective in enhancing the behavioral and pathological parameters switch in rats with arsenic-induced poisoned brains.

Melatonin ameliorates arsenic-induced cardiotoxicity through the regulation of the Sirt1/Nrf2 pathway in rats

Chronic arsenic (As) exposure, mainly as a result of drinking contaminated water, is associated with cardiovascular diseases. Mitochondrial dysfunction, oxidative stress, inflammation, apoptosis, and autophagy have been suggested as the molecular etiology of As cardiotoxicity. Melatonin (Mel) is a powerful antioxidant. Mel improves diabetic cardiomyopathy, cardiac remodeling, and heart failure. Following pre-treatment with Mel (10, 20, or 30 mg/kg/day i.p.), rats were orally gavaged with As (15 mg/kg/day) for 28 days. Electrocardiographic findings showed that Mel decreased the As-mediated QT interval prolongation. The effects of As on cardiac levels of glutathione (GSH) and malondialdehyde (MDA) were reversed by Mel pretreatment. Mel also modulated the Sirt1 and Nrf2 expressions promoted by As. Mel down-regulated autophagy markers such as Beclin-1 expression and the LC3-II/I ratio. Moreover, the cardiac expression of cleaved-caspase-3 and Bax/Bcl-2 ratio was decreased by Mel pretreatment. Reduced expression of miR-34a and miR-144 by As were reversed by Mel. The histopathological changes of cardiac injury associated with As exposure was moderated by Mel. Mel may improve As-induced cardiac dysfunction through anti-oxidative, anti-apoptotic, and anti-autophagic mechanisms.

Nrf2/Keap1 pathway in countering arsenic-induced oxidative stress in mice after chronic exposure at environmentally-relevant concentrations

Contamination of drinking water by carcinogen arsenic (As) is of worldwide concern as its exposure poses potential threat to human health. As such, it is important to understand the mechanisms associated with As-induced toxicity to humans. The Nrf2/Keap1 signal pathway is one of the most important defense mechanisms in cells to counter oxidative stress; however, limited information is available regarding its role in countering As-induced stress in model animal mouse. In this study, we assessed the responses of Nrf2/keap1 pathway in mice after chronic exposure to As at environmentally-relevant concentrations of 10-200 μg L^-1 for 30 days via drinking water. Our results indicate that chronic As exposure had limited effect on mouse growth. However, As induced oxidative stress to mice as indicated by increased content of malondialdehyde (MDA; 52-90%), an index of lipid peroxidation. Further, arsenic exposure reduced the activity of superoxide dismutase (SOD; 14-18%), an indication of reduced anti-oxidative activity. Besides, arsenic exposure increased MnSOD mRNA transcription by 25-66%, and decreased the mRNA transcriptions of Cu/ZnSOD by 72-83% and metallothionein by 16-75%, a cysteine-rich protein involved in metal detoxification. To counter arsenic toxicity, the expression of transcription factor for Nrf2 and Keap1 was increased by 2.8-8.9 and 0.2-8.1 fold in mice. To effectively reduce As-induced oxidative stress, the Nrf2/Keap1 transcription factor upregulated several downstream anti-oxidative genes, including heme oxygenase-1 (0.9-2.5 fold), glutamate-cysteine ligase catalytic subunit (0.6-1.7 fold), and NADH quinone dehydrogenase 1 (2.1-4.8 fold). This study shows the importance of Nrf2/Keap1 signaling pathway and associated anti-oxidative enzymes in countering As-toxicity in mice, possibly having implication for human health.

Apricot Kernel: Bioactivity, Characterization, Applications, and Health Attributes

Apricot kernel, a by-product of apricot fruit, is a rich source of proteins, vitamins, and carbohydrates. Moreover, it can be used for medicinal purposes and the formation of food ingredients. Several techniques have been adopted for the extraction of bioactive compounds from the apricot kernel such as solvent extraction, ultra-sonication, enzyme-assisted, microwave-assisted, and aqueous extraction. Apricot kernels may help to fight against various diseases such as cancer and cancer immunotherapy, as well as reduce blood pressure. Additionally, the kernel is famous due to its diverse industrial applications in various industries and fields of research such as thermal energy storage, the cosmetic industry, the pharmaceutical industry, and the food industry. Especially in the food industry, the apricot kernel can be used in the preparation of low-fat biscuits, cookies, cakes, and the fabrication of antimicrobial films. Therefore, in this review article, the bioactivity of the apricot kernel is discussed along with its chemical or nutritional composition, characterizations, and applications.

Nobiletin Ameliorates Cellular Damage and Stress Response and Restores Neuronal Identity Altered by Sodium Arsenate Exposure in Human iPSCs-Derived hNPCs

Environmental exposure to arsenic has been profoundly associated with chronic systemic disorders, such as neurodegeneration, in both experimental models and clinical studies. The neuronal cells of the brain and the nervous system have a limited regeneration capacity, thus making them more vulnerable to exposure to xenobiotics, leading to long-lasting disabilities. The functional and anatomical complexity of these cells hinders the complete understanding of the mechanisms of neurodegeneration and neuroprotection. The present investigations aimed to evaluate the neuroprotective efficacy of a herbal formulation of Nobiletin (NOB) against the toxic insult induced by sodium arsenate (NA) in human neural progenitor cells (hNPCs) derived from human induced pluripotent stem cells (hiPSCs). Prior to the neuroprotective experiments, biologically safe doses of both NOB and NA were ascertained using standard endpoints of cytotoxicity. Thereafter, the hNPCs were exposed to either NOB (50 μM) or NA (50 μM) and co-exposed to biologically safe concentrations of NA (50 μM) with NOB (50 μM) for a period of up to 48 h. NOB treatment restored the morphological damage (neurite damage), the levels of stress granule G3BP1 (Ras-GTPase-activating protein (SH3 domain)-binding protein) and TIA1 (T cell-restricted intracellular antigen), and the expression of neuronal markers (Tuj1, Nestin, MAP2, and PAX6) when compared to NA-exposed cells. A substantial restoration of reactive oxygen species and mitochondrial membrane potential was also witnessed in the co-exposure group (NA + NOB) in comparison to the NA-exposed group. The findings suggest that NOB possesses a significant restorative/protective potential against the NA challenge in hNPCs under experimental conditions and imply that nobiletin may impart a potential therapeutic impact if studied adequately using in vivo studies.

Therapeutic effects of CoenzymeQ10, Biochanin A and Phloretin against arsenic and chromium induced oxidative stress in mouse (Mus musculus) brain

Arsenic and chromium are the most common environmental toxicants prevailing in nature. Hence, the present study endeavors to investigate the salutary effects of Coenzyme Q10 (CoQ10), Biochanin A (BCA), and Phloretin (PHL) on the combined neurotoxic impact of arsenic and chromium in the Swiss albino mice (Mus musculus). Sodium meta-arsenite (100 ppm) and potassium dichromate (75 ppm) were given orally in conjugation with CoQ10 (10 mg/kg), BCA & PHL (50 mg/kg each) in accordance with body weight per day for the 2 weeks experimental duration. Weight reduction was figured out in the exposed toxic group of arsenic and chromium in contrast with the comparison group (control), and with the selected anti-oxidants treatment, it rose significantly to the basal status (p < 0.05). The concentration of arsenic and chromium was reduced significantly (p < 0.001) amidst all the natural compounds co-medicated groups. Anti-oxidant indicators, viz. lipid peroxidation (LPO) and protein carbonyl content (PCC), were found elevated, with reduction observed in the levels of superoxide dismutase (SOD), reduced glutathione (GSH), glutathione s-transferase (GST), and total thiols (TT) in the arsenic and chromium, co-exposed mice. The alterations in redox homeostasis were well corroborated with the estimations of cholinesterase's enzymes (p < 0.05) along with DNA fragmentation assay and altered Nrf2 signaling. The administration of CoQ10, BCA, and PHL ameliorated the effects of arsenic and chromium induced oxidative stress in the exposed mice. Our research unfolds the remedial outcome of these natural compounds contrary to the combined arsenic and chromium associated-neurotoxicity in the experimental model.

Polyphenolics with Strong Antioxidant Activity from Acacia nilotica Ameliorate Some Biochemical Signs of Arsenic-Induced Neurotoxicity and Oxidative Stress in Mice

Neurotoxicity is a serious health problem of patients chronically exposed to arsenic. There is no specific treatment of this problem. Oxidative stress has been implicated in the pathological process of neurotoxicity. Polyphenolics have proven antioxidant activity, thereby offering protection against oxidative stress. In this study, we have isolated the polyphenolics from Acacia nilotica and investigated its effect against arsenic-induced neurotoxicity and oxidative stress in mice. Acacia nilotica polyphenolics prepared from column chromatography of the crude methanol extract using diaion resin contained a phenolic content of 452.185 ± 7.879 mg gallic acid equivalent/gm of sample and flavonoid content of 200.075 ± 0.755 mg catechin equivalent/gm of sample. The polyphenolics exhibited potent antioxidant activity with respect to free radical scavenging ability, total antioxidant activity and inhibition of lipid peroxidation. Administration of arsenic in mice showed a reduction of acetylcholinesterase activity in the brain which was counteracted by Acacia nilotica polyphenolics. Similarly, elevation of lipid peroxidation and depletion of glutathione in the brain of mice was effectively restored to normal level by Acacia nilotica polyphenolics. Gallic acid methyl ester, catechin and catechin-7-gallate were identified in the polyphenolics as the major active compounds. These results suggest that Acacia nilotica polyphenolics due to its strong antioxidant potential might be effective in the management of arsenic induced neurotoxicity.

Effects of acute arsenic exposure in two different populations of Hyalella curvispina amphipods from North Patagonia Argentina

Arsenic (As) is a toxic metalloid present in high levels in diverse regions of Argentina. The aim of this study was to determine acute As-mediated toxicity in two different populations of autochthonous Hyalella curvispina amphipods from a reference site (LB) and an agricultural one (FO) within North Patagonia Argentina. Previously, both populations exhibited significant differences in pesticide susceptibility. Lab assays were performed to determine acute lethal concentrations, as well as some biochemical parameters. Lethal concentration (LC₅₀) values obtained after 48 and 96 hr As exposure were not significantly different between these populations, although FO amphipods appeared slightly less susceptible. LC₅₀-48 hr values were 3.33 and 3.92 mg/L As, while LC₅₀-96 hr values were 1.76 and 2.14 mg/L As for LB and FO amphipods. The no observed effect concentration (NOEC) values were 0.5 mg/L As. Cholinesterase (ChE) activity was significantly diminished by As acute exposure (0.5-1.5 mg/L As), indicative of a significant neurotoxic action for this metalloid in both amphipod populations. Activities of catalase (CAT) and glutathione S-transferase (GST) and levels of reduced glutathione (GSH) were differentially altered following As exposure. CAT activity was increased after 96 hr As exposure. GST activity and GSH levels were significantly elevated followed by either a decrease or a return to control values after 96 hr treatment. However, additional studies are necessary to understand the mechanisms underlying the As-mediated oxidative effects in H. curvispina. Our findings suggest that measurement of ChE activity in H. curvispina amphipods might serve as a useful biomarker of As exposure and effect.

Potential Protective Effect of Coenzyme Q10 on Doxorubicin-Induced Neurotoxicity and Behavioral Disturbances in Rats

The aim of this study was to investigate the potential neuroprotective efficacy of coenzyme Q10 (CoQ10) against doxorubicin (DOX) -induced behavioral disturbances in rats. Female rats were randomly assigned into 4 groups as control, CoQ10, DOX, and DOX plus CoQ10. The CoQ10 groups received CoQ10 (200 mg kg^-1) for 21 days, and the DOX groups received DOX (4 mg kg^-1) on days 7 and 14 of the study. The open field (OF) and elevated plus maze (EPM) tests were performed to assess locomotor activity and anxiety levels. Additionally, malondialdehyde (MDA), and protein carbonyl (PC) levels and acetylcholinesterase (AChE), and glutathione peroxidase (GPx) activities and total antioxidant capacity (TAC) were quantified in brain tissue. DOX administration caused alterations in locomotor activity, and anxiety-like behaviors. Moreover, DOX produced significant elevation in AChE activity . PC level and GPx activity tended to alter with DOX administration. Co-treatment with CoQ10 significantly attenuated DOX-induced behavioral alterations via improving AChE activity in the brain tissue of rats. CoQ10 treatment may be potential for the alleviation of DOX-induced behavioral disturbances. This improvement might be due to the inhibition of AChE activity.

Effect of Selenium on Brain Injury in Chickens with Subacute Arsenic Poisoning

The aim of this study was to investigate the effects of different doses of selenium (Se) on oxidative damage and neurotransmitter-related parameters in arsenic (As)-induced broiler brain tissue damage. Two hundred 1-day-old avian broilers were randomly divided into five groups and fed the following diets: control group (As 0.1 mg/kg + Se 0.2 mg/kg), As group (As 3 mg/kg + Se 0.2 mg/kg), low-Se group (As 3 mg/kg + Se 5 mg/kg), medium-Se group (As 3 mg/kg + Se 10 mg/kg), and high-Se group (As 3 mg/kg + Se 15 mg/kg). Glutathione (GSH), glutathione peroxidase (GSH-PX), nitric oxide (NO), nitric oxide synthase (NOS) activity, glutamate (Glu) concentration, glutamine synthetase (GS) activity, acetylcholinesterase (TchE) activity, and the apoptosis rate of brain cells were measured. The results showed that 3 mg/kg dietary As could induce oxidative damage and neurotransmitter disorder of brain tissue, increase the apoptosis rate of brain cells and cause damage to brain tissue, decrease activities of GSH and GSH-PX, decrease the contents of NO, decrease the activities of iNOS and tNOS, increase contents of Glu, and decrease activities of Gs and TchE. Compared with the As group, the Se addition of the low-Se and medium-Se groups protected against As-induced oxidative damage, neurotransmitter disorders, and the apoptosis rate of brain cells, with the addition of 10 mg/kg Se having the best effect. However, 15 mg/kg Se not only did not produce a protective effect against As damage but actually caused similar or severe damage.

Coenzyme Q10 protected against arsenite and enhanced the capacity of 2,3-dimercaptosuccinic acid to ameliorate arsenite-induced toxicity in mice

BACKGROUND

Arsenic poisoning affects millions of people. The inorganic forms of arsenic are more toxic. Treatment for arsenic poisoning relies on chelation of extracellularly circulating arsenic molecules by 2,3-dimecaptosuccinic acid (DMSA). As a pharmacological intervention, DMSA is unable to chelate arsenic molecules from intracellular spaces. The consequence is continued toxicity and cell damage in the presence of DMSA. A two-pronged approach that removes extracellular arsenic, while protecting from the intracellular arsenic would provide a better pharmacotherapeutic outcome. In this study, Coenzyme Q10 (CoQ10), which has been shown to protect from intracellular organic arsenic, was administered separately or with DMSA; following oral exposure to sodium meta-arsenite (NaAsO2) - a very toxic trivalent form of inorganic arsenic. The aim was to determine if CoQ10 alone or when co-administered with DMSA would nullify arsenite-induced toxicity in mice.

METHODS

Group one represented the control; the second group was treated with NaAsO2 (15 mg/kg) daily for 30 days, the third, fourth and fifth groups of mice were given NaAsO2 and treated with 200 mg/kg CoQ10 (30 days) and 50 mg/kg DMSA (5 days) either alone or in combination.

RESULTS

Administration of CoQ10 and DMSA resulted in protection from arsenic-induced suppression of RBCs, haematocrit and hemoglobin levels. CoQ10 and DMSA protected from arsenic-induced alteration of WBCs, basophils, neutrophils, monocytes, eosinophils and platelets. Arsenite-induced dyslipidemia was nullified by administration of CoQ10 alone or in combination with DMSA. Arsenite induced a drastic depletion of the liver and brain GSH; that was significantly blocked by CoQ10 and DMSA alone or in combination. Exposure to arsenite resulted in significant elevation of liver and kidney damage markers. The histological analysis of respective organs confirmed arsenic-induced organ damage, which was ameliorated by CoQ10 alone or when co-administered with DMSA. When administered alone, DMSA did not prevent arsenic-driven tissue damage.

CONCLUSIONS

Findings from this study demonstrate that CoQ10 and DMSA separately or in a combination, significantly protect against arsenic-driven toxicity in mice. It is evident that with further pre-clinical and clinical studies, an adjunct therapy that incorporates CoQ10 alongside DMSA may find applications in nullifying arsenic-driven toxicity.

Neuroprotective effects of protocatechuic acid on sodium arsenate induced toxicity in mice: Role of oxidative stress, inflammation, and apoptosis

Arsenic is a toxic metalloid abundantly found in nature and used in many industries. Consumption of contaminated water mainly results in human exposure to arsenic. Toxicity (arsenicosis) resulting from arsenic exposure causes cerebral neurodegeneration. Protocatechuic acid (PCA), a phenol derived from edible plants, has antioxidant properties. The present study investigated the neuroprotective potential of PCA against arsenic-induced neurotoxicity in mice. Male Swiss albino mice were divided into four groups: (i) orally administered physiological saline, (ii) orally administered 100 mg/kg PCA, (iii) orally administered 5 mg/kg NaAsO₂, and (iv) orally administered 100 mg/kg PCA 120 min prior to oral administration of 5 mg/kg NaAsO₂. Each group received its respective treatment for 1 week, after which cortical tissues from each group were analyzed for various parameters of oxidative stress, proinflammatory cytokines, apoptosis-related proteins, and changes in histopathology. NaAsO₂-treatment resulted in a significant increase in lipid peroxidation (LPO), inducible nitric oxide synthetase (iNOs), and NO levels, with a decrease in the levels of both enzymatic (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) and non-enzymatic (glutathione) antioxidant markers. Arsenic increased proinflammatory cytokine (tumor necrosis factor-α and interleukin-1β) levels, enhanced caspase-3 and Bax expression, and reduced Bcl-2 expression. Furthermore, arsenic-exposure in mice decreased significantly acetylcholinesterase activity and brain-derived neurotrophic factor level in the cerebral cortex. Histopathological examination revealed changes in nerve cell cyto-architecture and distribution in arsenic-exposed brain tissue sections. PCA treatment before arsenic administration resulted in a positive shift in the oxidative stress and cytokine levels with decreased levels of LPO, iNOS, and NO. PCA pre-treatment considerably attenuated arsenic-associated histopathological changes in murine brain tissue. This study suggested that the presence of PCA may be responsible for the prevention of arsenic-induced neurotoxicity.

Association between Parameters Related to Oxidative Stress and Trace Minerals in Athletes

The aim of the present study was to evaluate the basal concentrations of malondialdehyde (MDA) nonenzymatic antioxidants, such as ascorbic acid, α-tocopherol, and retinol in plasma or erythrocytes, and the plasma concentrations of 16 trace minerals in endurance athletes from Extremadura (Spain). In addition, we aimed to assess the possible relationships between some parameters related to cellular oxidative stress with plasma concentrations of some trace minerals. Sixty-two national long-distance men athletes participated in this study. The parameters related to oxidative stress and antioxidant activity were analyzed through high pressure liquid chromatography (HPLC), and trace minerals analysis was performed by inductively coupled plasma mass spectrometry (ICP-MS). We found that plasma MDA was positively correlated with selenium and rubidium. Plasma ascorbic acid was positively correlated with manganese and negatively correlated with cobalt and cadmium. Erythrocyte ascorbic acid was related to arsenic and cesium. Plasma α-tocopherol correlated with copper and manganese negatively and positively with arsenic. Erythrocyte α-tocopherol was positively related to copper, rubidium, and lithium. The findings show that athletes with a high degree of training should monitor their intake and concentrations of α-tocopherol for its fundamental role of neutralizing the excess of reactive oxygen species produced by exercise and the prooxidant effects of several minerals such as arsenic, copper, and lithium.

Arsenic exposure with reference to neurological impairment: an overview

Arsenic (As) toxicity has become a public health and environmental problem, which is a serious issue in certain parts of the world. Many people are exposed to As through contaminated drinking water, food and soil, through occupation, etc. Chronic As exposure is linked to various hostile health effects including skin problems, cancer, diabetes, cardiovascular disease, reproductive and developmental and neurological problems in exposed subjects. Experimental existing data indicate that chronic As exposure affects the nervous system by impairing the nerve and brain tissues of the exposed animals, and clinical studies indicate that As exposure leads to both central nervous system and peripheral nervous system impairments and also causes depression, memory impairment and difficulty in problem solving, affects body coordination, etc. Various prenatal and postnatal studies with respect to As exposure also suggest that developing offspring and young children are susceptible to As exposure. The only solution to this serious health problem is to stop occupational As exposure and provide As free drinking water to the affected population.

Manganese attenuates the effects of arsenic on neurobehavioral and biochemical changes in mice co-exposed to arsenic and manganese

An unsafe level of manganese (Mn) was detected in the drinking water in some arsenic (As)-contaminated areas in Bangladesh. Mn is an essential trace element; however, the intake of a higher level of Mn through the drinking water is associated with the development of toxicity in humans. This study was designed to evaluate the effects of As and Mn co-exposure on neurobehavioral and biochemical alterations in a mouse model. Sodium arsenite (10 mg/kg body weight) and manganese chloride tetrahydrate (10 mg/kg body weight) were given to mice individually and in combination with drinking water for 90 days. Results showed that individual As and Mn exposure as well as co-exposure of As and Mn significantly (p < 0.05) reduced the percent of time spent in the open arms when compared with that of control mice. In addition, percent of time spent in open arms significantly (p < 0.05) increased in co-exposed mice compared with As exposure in elevated plus maze (42.05 ± 1.10 versus 38.94 ± 0.66). In the Morris water maze test, the mean time latency to find the platform was longer in metal-treated mice in comparison to that of control mice (p < 0.05). Importantly, the co-exposed group had shorter time when compared with the As-exposed group during the training periods (p < 0.05). Moreover, co-exposed mice stayed significantly (p < 0.05) more time in the target quadrant in the probe trial in comparison with that of As-exposed mice (27.25 ± 1.21 versus 23.83 ± 0.87 s) but less time than control mice (27.25 ± 1.21 versus 43.17 ± 1.49 s). In addition, a significant (p < 0.05) alteration of biochemical parameters such as ALT, AST, ALP, BChE, and SOD as well as urea and creatinine levels were noted in the As-exposed group compared with the control group and Mn significantly (p < 0.05) attenuated the effects of As in co-exposed mice. Therefore, the results of this study suggest that As and Mn may have some antagonistic effect and Mn could attenuate the As-induced neurobehavioral and biochemical alterations in co-exposed mice.

First evaluation of novel potential synergistic effects of glyphosate and arsenic mixture on Rhinella arenarum (Anura: Bufonidae) tadpoles

The toxicity of glyphosate-based herbicide (GBH) and arsenite (As(III)) as individual toxicants and in mixture (50:50 v/v, GBH-As(III)) was determined in Rhinella arenarum tadpoles during acute (48 h) and chronic assays (22 days). In both types of assays, the levels of enzymatic activity [Acetylcholinesterase (AChE), Carboxylesterase (CbE), and Glutathione S-transferase (GST)] and the levels of thyroid hormones (triiodothyronine; T3 and thyroxine; T4) were examined. Additionally, the mitotic index (MI) of red blood cells (RBCs) and DNA damage index were calculated for the chronic assay. The results showed that the LC50 values at 48 h were 45.95 mg/L for GBH, 37.32 mg/L for As(III), and 30.31 mg/L for GBH-As(III) (with similar NOEC = 10 mg/L and LOEC = 20 mg/L between the three treatments). In the acute assay, Marking's additive index (S = 2.72) indicated synergistic toxicity for GBH-As(III). In larvae treated with GBH and As(III) at the NOEC-48h (10 mg/L), AChE activity increased by 36.25% and 33.05% respectively, CbE activity increased by 22.25% and 39.05 % respectively, and GST activity increased by 46.75% with the individual treatment with GBH and by 131.65 % with the GBH-As(III) mixture. Larvae exposed to the GBH-As(III) mixture also showed increased levels of T4 (25.67 %). In the chronic assay at NOEC-48h/8 (1.25 mg/L), As(III) and GBH-As(III) inhibited AChE activity (by 39.46 % and 35.65%, respectively), but did not alter CbE activity. In addition, As(III) highly increased (93.7 %) GST activity. GBH-As(III) increased T3 (97.34%) and T4 (540.93%) levels. Finally, GBH-As(III) increased the MI of RBCs and DNA damage. This study demonstrated strong synergistic toxicity of the GBH-As(III) mixture, negatively altering antioxidant systems and thyroid hormone levels, with consequences on RBC proliferation and DNA damage in treated R. arenarum tadpoles.

The Neuroprotective Role of Coenzyme Q10 Against Lead Acetate-Induced Neurotoxicity Is Mediated by Antioxidant, Anti-Inflammatory and Anti-Apoptotic Activities

Heavy metal exposure, in lead (Pb) particularly, is associated with severe neuronal impairment though oxidative stress mediated by reactive oxygen species, and antioxidants may be used to abolish these adverse effects. This study investigated the potential neuroprotective role of coenzyme Q10 (CoQ₁₀) against lead acetate (PbAc)-induced neurotoxicity. Twenty-eight male Wistar albino rats were divided into four equal groups (n = 7) and treated as follows: the control group was injected with physiological saline (0.9% NaCl); the CoQ₁₀ group was injected with CoQ₁₀ (10 mg/kg); PbAc group was injected with PbAc (20 mg/kg); PbAc + CoQ₁₀ group was injected first with PbAc, and after 1 h with CoQ₁₀. All groups were injected intraperitoneally for seven days. PbAc significantly increased cortical lipid peroxidation, nitrate/nitrite levels, and inducible nitric oxide synthase expression, and decreased glutathione content, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase activity and mRNA expression, as well as nuclear factor erythroid 2–related factor 2 (Nrf2) and homoxygenase-1 (HO-1) expression. PbAc also promoted the secretion of interleukin-1ß and tumor necrosis factor-α, inhibited interleukin-10 production, triggered the activation of pro-apoptotic proteins, and suppressed anti-apoptotic proteins. Additionally, PbAc increased the cortical levels of serotonin, dopamine, norepinephrine, GABA, and glutamate, and decreased the level of ATP. However, treatment with CoQ₁₀ rescued cortical neurons from PbAc-induced neurotoxicity by restoring the balance between oxidants and antioxidants, activating the Nrf2/HO-1 pathway, suppressing inflammation, inhibiting the apoptotic cascade, and modulating cortical neurotransmission and energy metabolism. Altogether, our findings indicate that CoQ₁₀ has beneficial effects against PbAc-induced neuronal damage through its antioxidant, anti-inflammatory, anti-apoptotic, and neuromodulatory activities.

Influence of Chronic Coenzyme Q10 Supplementation on Cognitive Function, Learning, and Memory in Healthy and Diabetic Middle-Aged Rats

Diabetes mellitus can induce impairment in learning and memory. Cognitive and memory deficits are common in older adults and especially in those with diabetes. This is mainly because of hyperglycemia, oxidative stress, and vascular abnormalities. Coenzyme Q10 (CoQ10) can decrease oxidative stress, hyperglycemia, and inflammatory markers, and improve vascular function. Therefore, the aim of the present study was to investigate the possible effects of CoQ10 on cognitive function, learning, and memory in middle-aged healthy and diabetic rats. Adult middle-aged male Wistar rats (390-460 g, 12-13 months old) were divided into 6 experimental groups. Diabetes was induced by a single i.p. injection of streptozotocin (60 mg/kg). CoQ10 (20 or 120 mg/kg, orally by gavage) was administered for 45 days. The cognitive function and learning memory of rats were evaluated using novel object recognition (NOR) and passive avoidance tests. The discrimination index of the NOR test in the diabetic groups receiving CoQ10 (20 or 120 mg/kg) and the healthy group receiving CoQ10 (120 mg/kg) was significantly higher than that in the control group. In addition, the step through latency was significantly longer and the time spent in the dark compartment was significantly shorter in the diabetic groups receiving CoQ10 than in the control group. CoQ10 supplementation can improve learning and memory deficits induced by diabetes in older subjects. In addition, CoQ10 at higher doses can improve cognitive performance in older healthy subjects.

Effect of Coenzyme Q10 Supplementation on Testosterone

Enhancing testosterone production in males is a continuous research direction for many scientists in the field, due to its role as a principal sex hormone and as a crucial modulator of well-being and general health in humans. Since 1978, there have been more than 30 studies that have connected coenzyme Q₁₀ and testosterone. Such a link is attributable to the vigorous biological role of coenzyme Q₁₀ as a crucial member in the energy production route in humans and animals, which is thought to have a positive influence on testosterone production, and hence on infertility, particularly male infertility. However, this connection has not yet been deliberated. The present work systematically reviews and summarizes the influence of coenzyme Q₁₀ supplementation on testosterone. To accomplish this purpose, the Scopus, PubMed, and Web of Science databases were searched using the keywords “coenzyme Q₁₀” versus “testosterone” for English language papers from November 1978 through October 2018. Relevant articles were also discussed and included to address an integral discussion. In summary, to date the studies conducted on human males reveal insignificant effects of coenzyme Q₁₀ supplementation on testosterone. Similarly, rather than the reproductive toxicity studies, the studies conducted on animals did not show any positive influence of coenzyme Q₁₀ on testosterone. However, coenzyme Q₁₀ supplementation was found to ameliorate the reduction in testosterone induced by chemical reproductive toxicants, mainly by neutralizing the damaging effect of the generated free radicals. However, collectively these findings require further confirmation by additional research studies.