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Background: Oxidative stress mediated by reactive oxygen species (ROS) is a common denominator in arsenic toxicity. Arsenic stress in soil affects the water absorption, decrease stomatal conductance, reduction in osmotic, and leaf water potential, which restrict water uptake and osmotic stress in plants. Arsenic-induced osmotic stress triggers the overproduction of ROS, which causes a number of germination, physiological, biochemical, and antioxidant alterations. Antioxidants with potential to reduce ROS levels ameliorate the arsenic-induced lesions. Plant growth promoting rhizobacteria (PGPR) increase the total soluble sugars and proline, which scavenging OH radicals thereby prevent the oxidative damages cause by ROS. The main objective of this study was to evaluate the potential role of Arsenic resistant PGPR in growth of maize by mitigating arsenic stress. Methodology: Arsenic tolerant PGPR strain MD3 (Pseudochrobactrum asaccharolyticum) was used to dismiss the 'As' induced oxidative stress in maize grown at concentrations of 50 and 100 mg/kg. Previously isolated arsenic tolerant bacterial strain MD3 "Pseudochrobactrum asaccharolyticum was used for this experiment. Further, growth promoting potential of MD3 was done by germination and physio-biochemical analysis of maize seeds. Experimental units were arranged in Completely Randomized Design (CRD). A total of 6 sets of treatments viz., control, arsenic treated (50 & 100 mg/kg), bacterial inoculated (MD3), and arsenic stress plus bacterial inoculated with three replicates were used for Petri plates and pot experiments. After treating with this MD3 strain, seeds of corn were grown in pots filled with or without 50 mg/kg and 100 mg/kg sodium arsenate. Results: The plants under arsenic stress (100 mg/kg) decreased the osmotic potential (0.8 MPa) as compared to control indicated the osmotic stress, which caused the reduction in growth, physiological parameters, proline accumulation, alteration in antioxidant enzymes (Superoxide dismutase-SOD, catalase-CAT, peroxidase-POD), increased MDA content, and H2O2 in maize plants. As-tolerant Pseudochrobactrum asaccharolyticum improved the plant growth by reducing the oxidation stress and antioxidant enzymes by proline accumulation. PCA analysis revealed that all six treatments scattered differently across the PC1 and PC2, having 85.51% and 9.72% data variance, respectively. This indicating the efficiency of As-tolerant strains. The heatmap supported the As-tolerant strains were positively correlated with growth parameters and physiological activities of the maize plants. Conclusion: This study concluded that Pseudochrobactrum asaccharolyticum reduced the 'As' toxicity in maize plant through the augmentation of the antioxidant defense system. Thus, MD3 (Pseudochrobactrum asaccharolyticum) strain can be considered as bio-fertilizer. [ABSTRACT FROM AUTHOR]

Arsenic (As) toxicity is a serious hazard to agricultural land due to growing industrialization, which has a negative effect on wheat crop yields. To address this issue, using seaweed extract and Azospirillum brasilense has emerged as an effective strategy for improving yield under stress conditions. However, the combined application of A. brasilense and seaweed extract in wheat crops under As toxicity has not been fully explored. The effectiveness of combining A. brasilense and seaweed extract in reducing As toxicity in wheat production was examined in this study through a 2-year pot experiment with nine treatments. These treatments included a control with no additives and two As concentrations (50 and 70 μM). At 50 and 70 μM, As was tested alone, with seaweed extract, with A. brasilense, and both. Significant results were achieved in reducing As toxicity in wheat crops. Arsenic at 70 μM proved more harmful than at 50 μM. The application of A. brasilense and seaweed extract was more effective in improving crop growth rates, chlorophyll levels, and stomatal conductance. The combined application notably decreased As concentration in wheat plants. It was concluded that applying A. brasilense and seaweed extract not only improves wheat growth but can also improve soil parameters under As toxicity conditions by increasing organic matter contents, boosting nutrient availability, and increasing the production of antioxidant enzymes. [ABSTRACT FROM AUTHOR]

Arsenic (As) contamination of agricultural soils poses a serious threat to crop productivity and food safety. Zinc oxide nanoparticles (ZnONPs) have emerged as a potential amendment for mitigating the adverse effects of As stress in plants. Soybean crop is mostly grown on marginalized land and is known for high accumulation of As in roots than others tissue. Therefore, this study aimed to elucidate the underlying mechanisms of ZnONPs in ameliorating arsenic toxicity in soybean. Our results demonstrated that ZnOB significantly improved the growth performance of soybean plants exposed to arsenic. This improvement was accompanied by a decrease (55%) in As accumulation and an increase in photosynthetic efficiency. ZnOB also modulated hormonal balance, with a significant increase in auxin (149%), abscisic acid (118%), gibberellin (160%) and jasmonic acid content (92%) under As(V) stress assuring that ZnONPs may enhance root growth and development by regulating hormonal signaling. We then conducted a transcriptomic analysis to understand further the molecular mechanisms underlying the NPs-induced As(V) tolerance. This analysis identified genes differentially expressed in response to ZnONPs supplementation, including those involved in auxin, abscisic acid, gibberellin, and jasmonic acid biosynthesis and signaling pathways. Weighted gene co-expression network analysis identified 37 potential hub genes encoding stress responders, transporters, and signal transducers across six modules potentially facilitated the efflux of arsenic from cells, reducing its toxicity. Our study provides valuable insights into the molecular mechanisms associated with metalloid tolerance in soybean and offers new avenues for improving As tolerance in contaminated soils. [ABSTRACT FROM AUTHOR]

Background: Grain quality is an important index of rice production, particularly when plants are grown under stress. Arsenic (As) contamination in paddy fields severely affects rice grain yield and quality. Here, the effects of As and combinations of As(III)-oxidizing bacteria (Pseudomonas stutzeri 4.25, 4.27, and 4.44) and plant growth-promoting bacteria (Delftia acidovorans KKU2500-12 and Cupriavidus taiwanensis KKU2500-3) on enzymes related to starch accumulation in grains and the grain quality of Khao Dawk Mali 105 rice cultivated in As-contaminated soil under greenhouse conditions were investigated. Results: Arsenic affected the activities of starch biosynthesis-related enzymes, and decreases of up to 76.27%, 71.53%, 49.74%, 73.39%, and 47.46% in AGPase, SSS, GBSS, SBE, and SDBE activities, respectively, and 9.42–61.07% in starch accumulation in grains were detected after growth in As-contaminated soil. However, the KKU2500-3/4.25 and KKU2500-3/4.44 combinations yielded the greatest enzyme activities in grains, and compared with the results observed in uninoculated seedlings, increases in starch accumulation of up to 51.16% and 23.81% were found in the inoculated seedlings after growth in medium- and high-As-contaminated soils, at 10–17 and 10–24 days after anthesis, respectively. The bacteria increased the 2-AP content in rice under As stress, possibly via the induction of proline, a 2-AP substrate. Bacterium-inoculated rice had significantly greater 2-AP levels than uninoculated rice, and 2.16–9.93% and 26.57–42.04% increases were detected in rice plants grown in medium- and high-As-contaminated soils, respectively. Conclusions: Arsenic toxicity can be mitigated in rice growing under greenhouse conditions by maintaining starch biosynthesis, accumulating amylose, and increasing 2-AP content. The effectiveness of these bacteria should be validated in paddy fields; hence, safe rice grains with a good starch content and aroma could be produced. Highlights: As(III) oxidation and PGPB improved the quality of the KDML 105 rice grains. Bacteria maintained starch biosynthesis-related enzyme activity in As-contaminated soils. Bacteria increased starch accumulation and the 2-AP aromatic content in rice grains. Bacteria improved the crop yield and grain quality of As-stressed rice plants. [ABSTRACT FROM AUTHOR]

The present study evaluated the repercussions of magnetopriming on the root system architecture of soybean plants subjected to arsenic toxicity using synchrotron radiation source based micro-computed tomography (SR-µCT). This will be used evey where as abbreviation for the technique for threedimensional imaging. Seeds of soybean were exposed to the static magnetic field (SMF) of strength (200 mT) for 1h prior to sowing. Magnetoprimed and nonprimed seeds were grown for 1 month in a soil-sand mixture containing four different levels of sodium arsenate (0, 5, 10, and 50 mg As kg-1 soil). The results showed that arsenic adversely affects the root growth in non-primed plants by reducing their root length, root biomass, root hair, size and number of root nodules, where the damaging effect of As was observed maximum at higher concentrations (10 and 50 mg As kg-1 soil). However, a significant improvement in root morphology was detected in magnetoprimed plants where SMF pretreatment enhanced the root length, root biomass, pore diameter of cortical cells, root hair formation, lateral roots branching, and size of root nodules and girth of primary roots. Qualitative analysis of x-ray micro-CT images showed that arsenic toxicity damaged the epidermal and cortical layers of the root as well as reduced the pore diameter of the cortical cells. However, the diameter of cortical cells pores in magnetoprimed plants was observed higher as compared to plants emerged from non-primed seeds at all level of As toxicity. Thus, the study suggested that magnetopriming has the potential to attenuate the toxic effect of As and could be employed as a pre-sowing treatment to reduce the phytotoxic effects of metal ions in plants by improving root architecture and root tolerance index. This study is the very first exploration of the potential benefits of magnetopriming in mitigating the toxicity of metals (As) in plant roots utilizing the micro-CT technique. [ABSTRACT FROM AUTHOR]

Arsenic (As) contamination is a major environmental pollutant that adversely affects plant physiological processes and can hinder nutrients and water availability. Such conditions ultimately resulted in stunted growth, low yield, and poor plant health. Using rhizobacteria and composted biochar (ECB) can effectively overcome this problem. Rhizobacteria have the potential to enhance plant growth by promoting nutrient uptake, producing growth hormones, and suppressing diseases. Composted biochar can enhance plant growth by improving aeration, water retention, and nutrient cycling. Its porous structure supports beneficial microorganisms, increasing nutrient uptake and resilience to stressors, ultimately boosting yields while sequestering carbon. Therefore, the current study was conducted to investigate the combined effect of previously isolated Bacillus faecalis (B. faecalis) and ECB as amendments on maize cultivated under different As levels (0, 300, 600 mg As/kg soil). Four treatments (control, 0.5% composted biochar (0.5ECB), B. faecalis, and 0.5ECB + B. faecalis) were applied in four replications following a completely randomized design. Results showed that the 0.5ECB + B. faecalis treatment led to a significant rise in maize plant height (~ 99%), shoot length (~ 55%), root length (~ 82%), shoot fresh (~ 87%), and shoot dry weight (~ 96%), root fresh (~ 97%), and dry weight (~ 91%) over the control under 600As stress. There was a notable increase in maize chlorophyll a (~ 99%), chlorophyll b (~ 81%), total chlorophyll (~ 94%), and shoot N, P, and K concentration compared to control under As stress, also showing the potential of 0.5ECB + B. faecalis treatment. Consequently, the findings suggest that applying 0.5ECB + B. faecalis is a strategy for alleviating As stress in maize plants. [ABSTRACT FROM AUTHOR]

Arsenic (As) poisoning has become a global public problem threatening human health. Chelation therapy (CT) is the preferred treatment for arsenic poisoning. Nevertheless, efficient and safe arsenic removal in vivo remains a daunting challenge due to the limitations of chelators, including weak affinity, poor cell membrane penetration, and short half-life. Herein, a mercapto-functionalized and size-tunable hierarchical porous Zr-MOF (UiO-66-TC-SH) is developed, which possesses abundant arsenic chemisorption sites, effective cell uptake ability, and long half-life, thereby efficiently removing toxic arsenic in vivo. Moreover, the strong binding affinity of UiO-66-TC-SH for arsenic reduces systemic toxicity caused by off-target effects. In animal trials, UiO-66-TC-SH decreases the blood arsenic levels of acute arsenic poisoning mice to a normal value within 48 h, and the efficacy is superior to clinical drugs 2,3-dimercaptopropanesulfonic acid sodium salt (DMPS). Meanwhile, UiO-66-TC-SH also significantly mitigates the arsenic accumulation in the metabolic organs of chronic arsenic poisoning mice. Surprisingly, UiO-66-TC-SH also accelerates the metabolism of arsenic in organs of tumor-bearing mice and alleviates the side effects of arsenic drugs antitumor therapy. Arsenic (As) contamination has become a global problem threatening public health. The present clinical chelation therapy (CT) still has some limitations, including the weak affinity, poor cell membrane permeability and short half-life of hydrophilic chelators. Herein, a metal−organic framework (MOF)-based multieffective arsenic removal strategy in vivo is proposed for the first time. Mercapto-functionalized and size-tunable hierarchical porous Zr-MOF nanoantidote (denoted as UiO-66-TC-SH) is accordingly designed and synthesized. After injection, UiO-66-TC-SH can form Zr− O −As bonds and As− S bonds with arsenic, thus enhancing arsenic adsorption capacity, cycling stability and systemic safety simultaneously. The acute arsenic poisoning model results indicate that UiO-66-TC-SH shows superior efficacy to the clinical drug sodium dimercaptopropanesulfonate (DMPS). More meaningfully, we find that UiO-66-TC-SH also accelerates the metabolism of arsenic in organs of tumor-bearing mice and alleviates side effects of arsenic drugs anti-tumor therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

The current work aims to prevent the adverse effects of arsenic poisoning in animal models by using a medicinal plant extract. The animals (Charles Foster rats) were exposed to Sodium arsenite at a dose of 8 mg per kg body weight for 90 days in order to develop an arsenic model. Leaf extract of Calendula officinalis at a dose of 200 mg per kg body weight was administered to these arsenic treated rats for 60 days to study the preventive effects of this plant extract. The study found that arsenic poisoning had an adverse effect on rats at the haematological, biochemical, and histopathological levels, but there was considerable normalization in the animal at all of these levels after the leaf extract administration of Calendula officinalis. As a result, it has ameliorative qualities against arsenic-induced toxicity and may be used therapeutically as a preventative medication. [ABSTRACT FROM AUTHOR]

Arsenic poisoning in groundwater is the most common environmental pollutant, which is leading to serious pollution worldwide. Chronic arsenic exposure from drinking water to humans causes major public health-related issues. The present study was conducted to investigate the antidote effects of Foeniculum vulgare (Fennel) against arsenic-induced hepatotoxicity and testicular toxicity in Charles Foster rats. In the present study, twenty-four male Charles Foster rats (120±5gm) were divided into four Groups (n=6), where control Group-I received a normal diet and water; Group - II and Group - III received sodium arsenite (8 mg per kg body weight per day) for 90 days. Group III was left with a normal diet and water for the next 60 days for auto-recovery. The group IV rats were administered Foeniculum vulgare (Funnel) hydroxyl ethanolic seed extract at a dose of 150 mg per kg body weight for 60 days in a 90-day pre)treated sodium arsenite group (8 mg per kg body weight). After complete dose duration, all the treated animals were sacrificed the same day for haematological, biochemical, hormonal, and histopathological studies. In the arsenic treated rats, there were significant (p<0.001) changes in serum levels of SGPT, SGOT, urea, uric acid and creatinine as well as in haematological parameters. And there was also decease in the sperm count and sperm motility, accompanied by an increased incidence of sperm abnormalities and hormonal imbalances leading to infertility. In contrast, after the administration of F. vulgare seeds hydroxy-ethanolic extract to arsenic-treated rats, significant (p<0.001) improvements were observed in hepatic and renal parameters as well as haematological parameters. In the arsenic-intoxicant rat, after administration of F. vulgare seeds hydroxyl ethanolic extract, there was a significant (p<001) reduction in the arsenic concentration in blood, liver, and kidney tissues as well as serum LPO. The histopathological study also showed the F. vulgare seeds hydroxy-ethanolic extract significantly restored the cellular integrity of testicular cells, leading to their normal functioning against arsenic-induced toxicity. [ABSTRACT FROM AUTHOR]

The presence of arsenic (As) metalloid in groundwater poses serious threat to human and animal’s health. Approx. 300 million people of about 105 countries in the world are affected due to arsenite poisoning. Except mitigation there is no such mode by which the population can be prevented from being exposed to arsenic. Elaeocarpus sphaericus (E. sphaericus) is widely used in the folk medicine system for the treatment of various diseases. Hence, present study aimed to investigate the Bio-remedial Impact of ESSE against As-Induced Nephrotoxicity in Charles foster rats. Male twenty-four rats (weighing 160 ± 20 g) were randomly assigned into two groups, where Group-I (n=6) rats were used as control. Group-II (n=18) rats were treated with sodium arsenite at 8 mg/Kg body weight for 90 days daily and then further divided into three sub-groups. Sub-Group I (n=6); rats were sacrificed and data were collected, Sub-Group II (n=6); rats were left for 60 days for auto recovery (as As-pre-treated group), and Sub-Group II (n=6); rats were administrated with E. sphaericus at 20mg/kg body weight for 60 days. After the completion of entire experimental dose all the control and treatment group were sacrificed to evaluate the various parameters. As-Induced rats had Significant (p<0.0001) alteration in haematological parameters. As-Induced serum levels of urea, uric acid, creatinine and albumin had significant (p<0.0001) alteration. Level of MDA and BUN were significantly (p<0001) increased. However, ESSE administration significantly reduced the adverse effect related to test of nephrological functions, MDA level significantly (p<0.0001) reduced. Dose dependent ESSE administration combat As)Induced toxicity and significantly (P<0.0001) normalise the level of haematological parameters. Hence, the study concluded that E. sphaericus seed might be used as a nutritional supplement to combat the arsenic led toxicity among the exposed population. [ABSTRACT FROM AUTHOR]

Globally, 300 million people worldwide are exposed to groundwater arsenic poisoning in the recent time, while an estimated 10 million population are exposed to arsenic poisoning in Bihar (India). The arsenic contamination in ground water has caused serious health hazards in the exposed population. The typical symptoms of arsenicosis are observed in the exposed population mostly skin manifestations such as hyperkeratosis, melanosis, loss of appetite, neuro-behavioral disorders etc. Hence, the present study aims to develop novel drug discovery against arsenic induced toxicity in rat models. In the present study treatment groups received sodium arsenite orally at the dose of 8 mg/kg body weight daily for 90 days followed by administration of Ocimum sanctum (Tulsi) seed extract at the dose of 500 mg/ kg body weight daily by gavage method for 60 days. Their biochemical levels like liver and kidney function tests were assayed and were found with elevated levels. Furthermore, their free radical assessment such as lipid peroxidation levels were assayed which was also found to be many folds higher. Furthermore, the arsenic concentration in the tissue of liver and kidney was significantly very high. But, after the administration of ethanolic seed extract of Ocimum sanctum, there was significant restoration in the biochemical and lipid peroxidation levels. Moreover, there was also reduction in the arsenic content in the liver and kidney tissues of rats. The phytoremedial effect of this novel plant (Ocimum sanctum) denotes that it possesses antidote effect against arsenic induced toxicity. [ABSTRACT FROM AUTHOR]

Increased levels of the non-essential hazardous metalloid arsenic (As) in rice grains pose a threat to human health and the sustainability of the rice industry. In several counties, the average As contamination in polished rice has been detected to range from 0.002 to 0.39 mg/kg, which is above the safe limit of 1 mg/kg as recommended by the World Health Organisation. Beyond this limit, the digestive tract, circulatory system, skin, liver, kidney, nervous system and heart can be affected. Humans can develop cancer from consuming or inhaling As. In addition, long-term exposure to drinking water contaminated with arsenic has also been linked to a dose-response relationship with an increased risk of hypertension and diabetes mellitus. Rice has been shown to be an indirect source of arsenic accumulation in human bodies. Under flooded paddy soil, trivalent arsenate (AsIII) occupies 87-94% of the total As, while under non-flooded soil, pentavalent arsenate (AsV) predominates (73-96% of the total As). This review aims to provide a thorough and interdisciplinary understanding of the behaviour of As in the paddy soil and transportation to rice grain and further investigate efficient ways to limit arsenic contamination. Supplementation of soil with specific mineral nutrients such as iron (Fe), sulphur (S) and silicon (Si) can significantly decrease the arsenic accumulation in rice grain by minimising its uptake and translocation. The hydrogen bonding potentials of uronic acids, proteins and amino sugars on the extracellular surface of soil microorganisms facilitate the detoxification of arsenic species. Further, rice is absorbed less when exposed to aerobic water management practices than anaerobic ones since it reduces the build-up of As in rice, and the solution is immobilised as in the soil. [ABSTRACT FROM AUTHOR]

Arsenic catastrophe has caused serious health hazards to the exposed population. An estimated 10 million people are exposed to arsenic poisoning through groundwater. The arsenic contamination through ground water has caused health diseases such as skin manifestations, loss of appetite, nausea, bowel disorders, neurological disorders etc. Therefore, there is need for search for proper therapeutic drug against arsenic induced toxicity in rats. In the present study, arsenic induced toxic model was developed by treating Charles Foster rats (n=18) with sodium arsenite orally at the dose of 8 mg/kg body weight daily for 60 days followed by administration of Bacopa moneri (Brahmi) leaf extract at the dose of 30mg/kg body weight daily by gavage method for 60 days. After the completion of the experiment, all the animals were sacrificed and their blood samples were collected along with their vital tissues. Following parameters were assayed such as haematological assay, biochemical assay and histopathological evaluation in the present study. The haematological study comprised of RBC counts, WBC counts, platelets counts and heamoglobin percentage. For biochemical evaluation, the liver function test and the kidney function test parameters along with free radical assay were carried out. The histopathological study also showed very high degree of degeneration in the hepatocytes and the nephrocytes in the vital organ's liver and kidney. But, after the administration of ethanolic leaf extract of Bacopa moneri, there was marked restoration in the studied parameters. The haematological parameters, the biochemical parameters as well as the histopathological study showed very significant outcomes. Therefore, the present studied medicinal plant Bacopa moneri possesses antidote effect against arsenic induced toxicity in Charles Foster rats which can be used as therapeutic drug in the future after clinical approval. [ABSTRACT FROM AUTHOR]

Arsenic contamination is a serious issue throughout the world and is substantial risk factor in most of the countries including India. Chronic arsenic exposure from drinking water to humans is causing major public health related issues. The present study aims to investigate the ameliorative effect of Citrullus lanatus (Watermelon) seeds against arsenic induced reproductive function and testicular toxicity in Charles Foster rats. In the present study, twenty-four male Charles Foster rats (120±5gm). The study group includes group - I (n=6) as control, and group - II (n=18) treated with sodium arsenite (8 mg per Kg body weight per day) for 90 days. The group - II was furthermore divided into three sub-groups, Group - II-a, Group - II-b and Group - II-c. The group - II-a were sacrificed to see the effect of arsenic toxicity effect after arsenic exposure. Group - II-b was left with normal food and water for next 60 days to observe auto recovery. The group - II-c rats were administered with Citrullus lanatus (Watermelon) hydroxyl ethanolic seeds extract at the dose of 400 mg per Kg body weight per day for 60 days for 90 days upon pre-treated sodium arsenite treated group (8 mg per kg body weight). After completion of the experiment, all the treated group of animals were sacrificed for biochemical, hormonal assay, histopathological, testicular and reproductive functions study. In the arsenic treated rats' group, there was significant (p<0.001) changes in serum levels of SGPT, SGOT, urea, uric acid and creatinine as well as in haematological parameters. There was decrease in the sperm counts and sperm motility accompanied by an increased incidence of sperm abnormalities and hormonal imbalance denotes infertility condition. In contrast, after the administration with C.lanatus (Watermelon) seeds hydroxy-ethanolic extract upon arsenic treated rats group, there was significant (p<0.001) improvement observed in the reproductive, hepatic and renal parameters. In the arsenic intoxicant rats' group, after administration with C. lanatus (Watermelon) seeds hydroxyl ethanolic extract, there was significant (p<001) reduction in the arsenic concentration in blood, liver, and kidney tissues as well as serum lipid peroxidation. The histopathological study also showed the C. lanatus (Watermelon) seeds hydroxy ethanolic extract significantly restored the cellular integrity of testicular cells leading to normal functioning of it against arsenic induced toxicity. [ABSTRACT FROM AUTHOR]

Groundwater contamination in India exposes an estimated 70 million people to arsenic. Over 10 million people in the state of Bihar (India) are at risk of arsenic poisoning. As reported 27 districts of the state's thirty-eight districts are under a state of catastrophe. Symptoms noticed by those who have been exposed to the arsenic caused disease are-lack of appetite, neurobehavioral problems, hyperkeratosis, and melanosis on the skin. So, this study's primary objective is to find novel approaches to treat arsenic poisoning in rats using the Charles Foster model. Following permission from the Institutional Animal Ethics Committee, the animals were divided into three groups: one group served as a control, the second group received arsenic treatment, and the third group received Ganoderma lucidum extract after arsenic treatment. For the arsenic group, the rats were given 8 mg/kg body weight of sodium arsenite orally every day for 90 days, and then for 60 days, they were given 80 mg/Kg body weight of Ganoderma lucidum extract via gavage. Their biochemical values, including those of the liver and kidneys, were found to be increased. In addition, their levels of free radicals, including lipid peroxidation, were measured and found to be substantially higher. In addition, the levels of arsenic in the kidney and liver tissue were very high. However, biochemical and lipid peroxidation levels were significantly restored after administration of Ganoderma lucidum ethanolic extract. Arsenic levels in rat liver and kidney tissues were also found to be reduced. Ganoderma lucidum has a therapeutic impact against arsenicinduced toxicity, according to the present research. [ABSTRACT FROM AUTHOR]

Arsenic, existing in various chemical forms such as arsenate (As(V)) and arsenite (As(III)), demands serious attention in water and environmental contexts due to its significant health risks. It is classified as "carcinogenic to humans" by the International Agency for Research on Cancer (IARC) and is listed by the World Health Organization (WHO) as one of the top 10 chemicals posing major public health concerns. This widespread contamination results in millions of people globally being exposed to dangerous levels of arsenic, making it a top priority for the WHO. Chronic arsenic toxicity, known as arsenicosis, presents with specific skin lesions like pigmentation and keratosis, along with systemic manifestations including chronic lung diseases, liver issues, vascular problems, hypertension, diabetes mellitus, and cancer, often leading to fatal outcomes. Therefore, it is crucial to explore novel, cost-effective, and reliable methods with rapid response and improved sensitivities (detection limits). Most of the traditional detection techniques often face limitations in terms of complexity, cost, and the need for sophisticated equipment requiring skilled analysts and procedures, which thereby impedes their practical use, particularly in resource-constrained settings. Colorimetric methods leverage colour changes which are observable and quantifiable using simple instrumentation or even visual inspection. This review explores the colorimetric techniques designed to detect arsenite and arsenate in water. It covers recent developments in colorimetric techniques, and advancements in the role of nanomaterials in colorimetric arsenic detection, followed by discussion on current challenges and future prospects. The review emphasizes efforts to improve sensitivity, selectivity, cost, and portability, as well as the role of advanced materials/nanomaterials to boost the performance of colorimetric assays/sensors towards combatting this pervasive global health concern. [ABSTRACT FROM AUTHOR]

The use of probiotic lactobacilli has been proposed as a strategy to mitigate damage associated with exposure to toxic metals. Their protective effect against cationic metal ions, such as those of mercury or lead, is believed to stem from their chelating and accumulating potential. However, their retention of anionic toxic metalloids, such as inorganic arsenic, is generally low. Through the construction of mutants in phosphate transporter genes (pst) in Lactiplantibacillus plantarum and Lacticaseibacillus paracasei strains, coupled with arsenate [As(V)] uptake and toxicity assays, we determined that the incorporation of As(V), which structurally resembles phosphate, is likely facilitated by phosphate transporters. Surprisingly, inactivation in Lc. paracasei of PhoP, the transcriptional regulator of the two-component system PhoPR, a signal transducer involved in phosphate sensing, led to an increased resistance to arsenite [As(III)]. In comparison to the wild type, the phoP strain exhibited no differences in the ability to retain As(III), and there were no observed changes in the oxidation of As(III) to the less toxic As(V). These results reinforce the idea that specific transport, and not unspecific cell retention, plays a role in As(V) biosorption by lactobacilli, while they reveal an unexpected phenotype for the lack of the pleiotropic regulator PhoP. [ABSTRACT FROM AUTHOR]

Background: Arsenic is a well-known toxin which may contaminate household water. It is harmful when ingested over prolonged periods of time. As a result, public health experts recommend that water should be screened and treated to prevent arsenic ingestion. In the United States, the responsibility of testing and treatment of private wells falls on homeowners. Despite recommendations for routine screening, this is rarely done. Objectives: To assess the prevalence of well water use in a Midwestern patient population, how patients and clinicians perceive the risks of arsenic in well water, and whether additional resources on well water testing are desired. These findings will be used to influence tools for clinicians regarding symptom and examination findings of chronic arsenic exposure and potentiate the distribution of informational resources on well water testing. Methods: Surveys were sent via email to all actively practicing primary care clinicians at the Mayo Clinic in the United States Midwest, and all active adult patients at the Mayo Clinic in the same region. Our team analyzed survey data to determine whether both patients and clinicians are aware of the health effects of chronic arsenic toxicity from well water, the need for routine well water testing and whether each group wants more information on the associated risks. Results: Both patients and primary care clinicians worry about arsenic exposure. Patients with well water are concerned about their water safety yet feel uninformed about testing options. Clinicians do not know how prevalent well water use is among their patients, feel uninformed about the chronic risks of arsenic exposure and the physical examination associated with it. Both groups unanimously want more information on testing options. Conclusions: Our findings show a significant reliance on well water use in the American Midwest, and unanimous support for the need for further well water testing information and resources for patients and their clinicians. [ABSTRACT FROM AUTHOR]

The health risks that arise from environmental exposures vary widely within and across human populations, and these differences are largely determined by genetic variation and gene-by-environment (gene–environment) interactions. However, risk assessment in laboratory mice typically involves isogenic strains and therefore, does not account for these known genetic effects. In this context, genetically heterogenous cell lines from laboratory mice are promising tools for population-based screening because they provide a way to introduce genetic variation in risk assessment without increasing animal use. Cell lines from genetic reference populations of laboratory mice offer genetic diversity, power for genetic mapping, and potentially, predictive value for in vivo experimentation in genetically matched individuals. To explore this further, we derived a panel of fibroblast lines from a genetic reference population of laboratory mice (the Diversity Outbred, DO). We then used high-content imaging to capture hundreds of cell morphology traits in cells exposed to the oxidative stress-inducing arsenic metabolite monomethylarsonous acid (MMAIII). We employed dose-response modeling to capture latent parameters of response and we then used these parameters to identify several hundred cell morphology quantitative trait loci (cmQTL). Response cmQTL encompass genes with established associations with cellular responses to arsenic exposure, including Abcc4 and Txnrd1, as well as novel gene candidates like Xrcc2. Moreover, baseline trait cmQTL highlight the influence of natural variation on fundamental aspects of nuclear morphology. We show that the natural variants influencing response include both coding and non-coding variation, and that cmQTL haplotypes can be used to predict response in orthogonal cell lines. Our study sheds light on the major molecular initiating events of oxidative stress that are under genetic regulation, including the NRF2-mediated antioxidant response, cellular detoxification pathways, DNA damage repair response, and cell death trajectories. Author summary: Exposure to environmental toxicants leads to adverse health outcomes. Natural genetic variation regulates the likelihood and severity of these outcomes, but studying the underlying genes and pathways in human populations is challenging. Population-based rodent models simulate the genetic variation of the human population offering numerous advantages as experimental genetic models for studying gene–environment interactions and in chemical risk asessment. These include exquisite environmental control and higher power for mapping the genes and pathways that influence sensitivity and resilience to environmental exposures. We leveraged a genetically diverse laboratory mouse population to investigate the genetic regulation of arsenic response. To minimize animal use, cells were derived from each individual animal through a minimally invasive tail biopsy. These cells provide a reusable genetic resource for chemical or drug screening through which predictions of risk can be made and tested in genetically matched laboratory mice. To evaluate the utility of this resource, we used high content imaging to quantify changes in cell morphology following exposure to the arsenic metabolite MMAIII. Using dose-response modeling, we identified the subset of morphological changes that are informative of arsenic response and that exhibit robust interindividual variation. We then used genetic association mapping to identify several hundred loci regulating individual differences in arsenic response. To nominate candidate driver genes, we integrated various lines of evidence from published arsenic studies and molecular data from the same mouse population. Our work demonstrates that genetic variation in the molecular pathways regulating arsenic transport, oxidative stress, and DNA damage contribute to variation in arsenic response. Additionally, we show that this genetic variation predicts cellular response in independent experiments. Our data establish a population-based approach for studying gene–environment interactions using inexpensive and high-throughput cell morphology traits in an experimental system that enables recursive in vitro and in vivo experimentation across genetically matched individuals. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa) is the primary crop for nearly half of the world's population. Groundwater in many rice-growing parts of the world often has elevated levels of arsenite and arsenate. At the same time, rice can accumulate up to 20 times more arsenic compared to other staple crops. This places an enormous amount of people at risk of chronic arsenic poisoning. In this study, we investigated whether Raman spectroscopy (RS) could be used to diagnose arsenic toxicity in rice based on biochemical changes that were induced by arsenic accumulation. We modeled arsenite and arsenate stresses in four different rice cultivars grown in hydroponics over a nine-day window. Our results demonstrate that Raman spectra acquired from rice leaves, coupled with partial least squaresdiscriminant analysis, enabled accurate detection and identification of arsenic stress with approximately 89% accuracy. We also performed high-performance liquid chromatography (HPLC)-analysis of rice leaves to identify the key molecular analytes sensed by RS in confirming arsenic poisoning. We found that RS primarily detected a decrease in the concentration of lutein and an increase in the concentration of vanillic and ferulic acids due to the accumulation of arsenite and arsenate in rice. This showed that these molecules are detectable indicators of biochemical response to arsenic accumulation. Finally, a cross-correlation of RS with HPLC and ICP-MS demonstrated RS's potential for a label-free, non-invasive, and nondestructive quantification of arsenic accumulation in rice. [ABSTRACT FROM AUTHOR]

BACKGROUND: Hypertension is a major cause of death worldwide. Although arsenic exposure has been associated with the risk of hypertension, this association appears nonuniform due to inconsistent results from studies conducted in different populations. Moreover, hypertension is a complex condition with multiple underlying mechanisms and factors. One factor is impaired production and bioavailability of vascular nitric oxide (NO). However, the implications of the effects of arsenic exposure on circulating NO and its association with hypertension in humans are largely unknown. OBJECTIVE: We investigated the dose–response relationship between arsenic exposure and hypertension with vascular NO levels as a potential mediator of arsenic-related hypertension in individuals exposed to a broad range of arsenic. METHODS: A total of 828 participants were recruited from low- and high-arsenic exposure areas in Bangladesh. Participants’ drinking water, hair, and nail arsenic concentrations were measured by inductively coupled plasma mass spectroscopy. Hypertension was defined as a systolic blood pressure (SBP) value of = 140 and a diastolic (DBP) value of = 90 mmHg. Serum NO levels reflected by total serum nitrite concentrations were measured by immunoassay. A formal causal mediation analysis was used to assess NO as a mediator of the association between arsenic level and hypertension. RESULTS: Increasing concentrations of arsenic measured in drinking water, hair, and nails were associated with the increasing levels of SBP and DBP. The odds of hypertension were dose-dependently increased by arsenic even in participants exposed to relatively low to moderate levels (10–50 µg/L) of water arsenic [odds ratios (ORs) and 95% confidence intervals (CIs): 2.87 (95% CI: 1.28, 6.44), 2.67 (95% CI: 1.27, 5.60), and 5.04 (95% CI: 2.71, 9.35) for the 10–50 µg/L, 50.01–150 µg/L, and >150 µg/L groups, respectively]. Causal mediation analysis showed a significant mediating effect of NO on arsenic-related SBP, DBP, and hypertension. CONCLUSION: Increasing exposure to arsenic was associated with increasing odds of hypertension. The association was mediated through the reduction of vascular NO bioavailability, suggesting that impaired NO bioavailability was a plausible underlying mechanism of arsenic-induced hypertension in this Bangladeshi population. [ABSTRACT FROM AUTHOR]

The article describes the case of a 24-year-old male patient who developed acute hemolytic anemia following arsenic poisoning. Topics include his medical history of the patient, differential diagnosis, confirmation of an ischemic stroke of the brain following a neurological consultation, and a discussion on arsenic poisoning.

A toxicogenomic approach was used for toxicity evaluation of arsenic in the aquatic environment, and differential gene expression was investigated from 24 h and 96 h water-only acute toxicity tests with the aquatic oligochaete, Tubifex tubifex (Annelida, Clitellata). Several toxicological endpoints (survival and autotomy) of the oligochaete and tissue residues were measured, and dose-response modelling of gene expression data was studied. A reference transcriptome of the aquatic oligochaete, T. tubifex, was reconstructed for the first time, and genes related to cell stress response (Hsc70, Hsp10, Hsp60, and Hsp83), energy metabolism (COX1), oxidative stress (Cat, GSR, and MnSOD), and the genes involved in the homeostasis of organisms (CaM, RpS13, and UBE2) were identified and characterised. The potential use of the genes identified for risk assessment in freshwater ecosystems as early biomarkers of arsenic toxicity is discussed. [ABSTRACT FROM AUTHOR]

Introduction: The toxicity of arsenic is widely recognized globally, mainly harming human health by polluting water, soil, and food. However, its formulations can also be used for the clinical treatment of diseases such as leukemia and tumors. Arsenic has been used as a drug in China for over 2,400 years, with examples such as the arsenic-containing drug realgar mentioned in Shennong's Herbal Classic. We have reviewed references on arsenic over the past thirty years and found that research has mainly focused on clinical, pharmacological, and toxicological aspects. Results and Discussion: The finding showed that in clinical practice, arsenic trioxide is mainly used in combination with all-trans retinoic acid (ATRA) at a dose of 10 mg/d for the treatment of acute promyelocytic leukemia (APL); realgar can be used to treat acute promyelocytic leukemia, myelodysplastic syndrome, and lymphoma. In terms of pharmacology, arsenic mainly exerts anti-tumor effects. The dosage range of the action is 0.01-80 μmol/L, and the concentration of arsenic in most studies does not exceed 20 μmol/L. The pharmacological effects of realgar include antiviral activity, inhibition of overactivated lactate dehydrogenase, and resistance to malaria parasites. In terms of toxicity, arsenic is toxic to multiple systems in a dose-dependent manner. For example, 5 μmol/L sodium arsenite can induce liver oxidative damage and promote the expression of pro-inflammatory factors, and 15 μmol/L sodium arsenite induces myocardial injury; when the concentration is higher, it is more likely to cause toxic damage. [ABSTRACT FROM AUTHOR]

The high toxicity of arsenic (As) can cause irreversible harm to the environment and human health. In this study, the chlorin e6 (Ce6), which emits fluorescence in the infrared region, was introduced as the luminescence center, and the addition of copper ion (Cu2+) and As(V) provoked a regular change in fluorescence at 652 nm, whereas that of As(III) was 665 nm, which was used to optionally detect Cu2+, arsenic (As(III), and As(V)). The limit of detection (LOD) values were 0.212 μM, 0.089 ppm, and 1.375 ppb for Cu2+, As(III), and As(V), respectively. The developed method can be used to determine Cu2+ and arsenic in water and soil with good sensitivity and selectivity. The 1:1 stoichiometry of Ce6 with Cu2+ was obtained from the Job plot that was developed from UV–visible spectra. The binding constants for Cu2+ and As(V) were established to be 1.248 × 105 M−1 and 2.35 × 1012 M−2, respectively, using B–H (Benesi–Hildebrand) plots. Fluorescence lifetimes, B–H plots, FT–IR, and 1H-NMR were used to postulate the mechanism of Cu2+ fluorescence quenching and As(V) fluorescence restoration and the interactions of the two ions with the Ce6 molecule. [ABSTRACT FROM AUTHOR]

Arsenic is frequently used in alternative medicine, and it is critical to promptly identify and treat suspected arsenic toxicity in patients. In a case study, a female patient presented with several symptoms, including nausea, vomiting, bilateral tinnitus, hearing loss, vertigo, and other associated complaints. After admission, the patient showed lethargy, and topical application of Chinese herbal medicine was found on her left breast, along with visible pigmentation on her torso. Examination revealed severe bilateral sensorineural deafness, liver and kidney injury, and pancytopenia. Due to the presence of broken skin, toxicological analysis detected elevated levels of arsenic in both blood (113 ng/mL) and urine (865.4 ng/mL). The patient was diagnosed with arsenic poisoning and received symptomatic treatment, including detoxification. Unfortunately, the patient died due to long-term exposure to arsenic. Therefore, early identification of the etiology is crucial for managing cases of arsenic poisoning. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chronic arsenic exposure has been associated with an increased risk of cardiovascular disease; diabetes; cancers of the lung, pancreas and prostate; and all-cause mortality in American Indian communities in the Strong Heart Study. OBJECTIVE: The Strong Heart Water Study (SHWS) designed and evaluated a multilevel, community-led arsenic mitigation program to reduce arsenic exposure among private well users in partnership with Northern Great Plains American Indian Nations. METHODS: A cluster randomized controlled trial (cRCT) was conducted to evaluate the effectiveness of the SHWS arsenic mitigation program over a 2-y period on a) urinary arsenic, and b) reported use of arsenic-safe water for drinking and cooking. The cRCT compared the installation of a pointof- use arsenic filter and a mobile Health (mHealth) program (3 phone calls; SHWS mHealth and Filter arm) to a more intensive program, which included this same program plus three home visits (3 phone calls and 3 home visits; SHWS Intensive arm). RESULTS: A 47% reduction in urinary arsenic [geometric mean (GM)=13.2 to 7.0 μg/g creatinine] was observed from baseline to the final follow-up when both study arms were combined. By treatment arm, the reduction in urinary arsenic from baseline to the final follow-up visit was 55% in the mHealth and Filter arm (GM=14.6 to 6.55 μg/g creatinine) and 30% in the Intensive arm (GM=11.2 to 7.82 μg/g creatinine). There was no significant difference in urinary arsenic levels by treatment arm at the final follow-up visit comparing the Intensive vs. mHealth and Filter arms: GM ratio of 1.21 (95% confidence interval: 0.77, 1.90). In both arms combined, exclusive use of arsenic-safe water from baseline to the final follow-up visit significantly increased for water used for cooking (17% to 53%) and drinking (12% to 46%). DISCUSSION: Delivery of the interventions for the community-led SHWS arsenic mitigation program, including the installation of a point-of-use arsenic filter and a mHealth program on the use of arsenic-safe water (calls only, no home visits), resulted in a significant reduction in urinary arsenic and increases in reported use of arsenic-safe water for drinking and cooking during the 2-y study period. These results demonstrate that the installation of an arsenic filter and phone calls from a mHealth program presents a promising approach to reduce water arsenic exposure among private well users. [ABSTRACT FROM AUTHOR]

Human health and sustainable agricultural production are both susceptible to numerous toxic metal(loid)s that cause serious chronic diseases in the human via food chain. There found no conspicuous knowledge which could address the proper strategic measures to limit arsenic (As) uptake in maize grains and improve seed nutritional value. Careful consultation of previous literature explored no single study till present day which could reveal about the contribution of seed-applied THI (thiamine) + IAA (indole-3-acetic acid) under toxic As stress (AsS) levels to enhance the seed nutritional value and minimize the As administered damages in specific context of plant nutrition and crop yield. For this purpose, current study was organized to limit the As-uptake in maize parts (root, shoot and grains) and to magnify the grain nutritional constituents. Seed-applied supplementation of THI (250 mgL−1), IAA (30 µM) and mixture (THI + IAA) under AsS levels (0, 50, 100 mg/kg) was investigated. The results demonstrated the significant (P ≤ 0.001) deteriorations in maize kernel proximate components (kernel sugars, proteins, fiber, oil fat, starch), crop yield and seed micro- and macronutrients when exposed to AsS. In contradiction, the maize plants developed from seed-applied THI and IAA treatments significantly (P ≤ 0.001) increased the maize yield, kernel proximate components and grain nutrients of under AsS and NS. Maximum significant (P ≤ 0.001) improvements of maize kernel nutrients, crop yield and proximate components were evident with combined seed application of THI + IAA as compared to alone applications under AsS and NS conditions. [ABSTRACT FROM AUTHOR]

Health concerns about the toxicity of arsenic compounds have therefore encouraged the development of new analytical tools for quick monitoring of arsenic in real samples with improved sensitivity, selectivity, and reliability. An overview of advanced optical colorimetric sensor techniques for real-time monitoring of inorganic arsenic species in the environment is given in this review paper. Herein, several advanced optical colorimetric sensor techniques for arsenite (As+3) and arsenate (As+5) based on doping chromogenic dyes/reagents, biomolecule-modified nanomaterials, and arsenic-binding ligand tethered nanomaterials are introduced and discussed. This review also highlights the benefits and limitations of the colorimetric sensor for arsenic species. Finally, prospects and future developments of an optical colorimetric sensor for arsenic species are also proposed. For future study in this sector, particularly for field application, authors recommend this review paper will be helpful for readers to understand the design principles and their corresponding sensing mechanisms of various arsenic optical colorimetric sensors. [ABSTRACT FROM AUTHOR]

The ongoing challenges of climate change and pollution are major factors disturbing ecosystems, including aquatic systems. They also have an impact on gene regulation and biochemical changes in aquatic animals, including fish. Understanding the mechanisms of gene regulation and biochemical changes due to climate change and pollution in aquatic animals is a challenging task. However, with this backdrop, the present investigation was conducted to explore the effects of arsenic (As) and ammonia (NH3) toxicity and high-temperature (T) stress on gene regulation and biochemical profiles, mitigated by dietary manganese (Mn) in Pangasianodon hypophthalmus. The fish were exposed to different combinations of As, NH3, and T, and fed with dietary Mn at 4, 8, and 12 mg kg−1 to evaluate the gene expression of immunity, antioxidative status, cytokine, and NfKB signaling pathway genes. HSP 70, cytochrome P450 (CYP 450), metallothionein (MT), DNA damage-inducible protein (DDIP), caspase (CAS), tumor necrosis factor (TNFα), toll-like receptor (TLR), interleukin (IL), inducible nitric oxide synthase (iNOS), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) were noticeably highly upregulated by As + NH3 + T stress, whereas Mn diet at 8 mg kg−1 downregulated these genes. Further, total immunoglobulin (Ig), myostatin (MYST), somatostatin (SMT), growth hormone (GH), growth hormone regulator 1 and β, insulin-like growth factors (IGF1X1 and IGF1X2) were significantly upregulated by Mn diets. The biochemical profiles were highly affected by stressors (As + NH3 + T). The bioaccumulation of arsenic in different tissues was also notably reduced by Mn diets. Furthermore, the infectivity of the fish was reduced, and survival against pathogenic bacteria was enhanced by Mn diet at 8 mg kg−1. The results of the present investigation revealed that dietary Mn at 8 mg kg−1 controls gene regulation against multiple stressors (As, NH3, As + NH3, NH3 + T, As + NH3 + T) in fish. [ABSTRACT FROM AUTHOR]

At a great many locations worldwide, the safety of drinking water is not assured due to pollution with arsenic. Arsenic toxicity is a matter of both systems chemistry and systems biology: it is determined by complex and intertwined networks of chemical reactions in the inanimate environment, in microbes in that environment, and in the human body. We here review what is known about these networks and their interconnections. We then discuss how consideration of the systems aspects of arsenic levels in groundwater may open up new avenues towards the realization of safer drinking water. Along such avenues, both geochemical and microbiological conditions can optimize groundwater microbial ecology vis-à-vis reduced arsenic toxicity. [ABSTRACT FROM AUTHOR]

Throughout history, cases of arsenic poisoning have been reported worldwide, and the highly toxic effects of arsenic to humans, plants, and animals are well documented. Continued anthropogenic activities related to arsenic contamination in soil and water, as well as its persistency and lethality, have allowed arsenic to remain a pollutant of high interest and concern. Constant scrutiny has eventually resulted in new and better techniques to mitigate it. Among these, microbial remediation has emerged as one of the most important due to its reliability, safety, and sustainability. Over the years, numerous microorganisms have been successfully shown to remove arsenic from various environmental matrices. This review provides an overview of the interactions between microorganisms and arsenic, the different mechanisms utilized by microorganisms to detoxify arsenic, as well as current trends in the field of microbial-based bioremediation of arsenic. While the potential of microbial bioremediation of arsenic is notable, further studies focusing on the field-scale applicability of this technology is warranted. [ABSTRACT FROM AUTHOR]

Many toxic metals are involved in the initiation and progression of DNA damage that can result in the activation of DNA damage response machinery at double- and single-stranded DNA; this response can result in global and gene-specific DNA alteration. The toxicological profiles from the Agency for Toxic Substances and Disease Registry (ATSDR) and several other studies have demonstrated the influence of metal exposure-induced genotoxic endpoints and epigenetic modifications. Our review systematically summarizes accumulating evidence from ATSDR toxicological profiles and the available literature that demonstrate a possible induction of various genotoxic endpoints and metal exposures. We include in this article studies on chromium, arsenic, nickel, lead, mercury, and zinc. [ABSTRACT FROM AUTHOR]

BACKGROUND: Inorganic arsenic (As) may increase the risk of cardiovascular disease (CVD) and all-cause mortality through accelerated aging, which can be estimated using epigenetic-based measures. OBJECTIVES: We evaluated three DNA methylation-based aging measures (PhenoAge, GrimAge, DunedinPACE) (epigenetic aging measures) as potential mediators of the previously reported association of As exposure with CVD incidence, CVD mortality, and all-cause mortality in the Strong Heart Study (SHS), an epidemiological cohort of American Indian adults. METHODS: Blood DNA methylation and urinary As levels were measured in 2,323 SHS participants (41.5% men, mean age of 55 years old). PhenoAge and GrimAge values were calculated using a residual-based method. We tested the association of urinary As with epigenetic aging measures using linear regression, the association of epigenetic aging measures with the three health outcomes using additive hazards models, and the mediation of As-related CVD incidence, CVD mortality, and all-cause mortality by epigenetic aging measures using the product of coefficients method. RESULTS: SHS participants with higher vs. lower urinary As levels had similar PhenoAge age, older GrimAge age, and faster DunedinPACE. An interquartile range increase in urinary As was associated with higher of PhenoAge age acceleration [mean difference (95% confidence interval)=0.48 (0.17, 0.80) years], GrimAge age acceleration [0.80 (0.60, 1.00) years], and DunedinPACE [0.011 (0.005, 0.018)], after adjusting for age, sex, center location, genetic components, smoking status, and body mass index. Of the 347 incident CVD events per 100,000 person-years associated with a doubling in As exposure, 21.3% (9.1, 57.1) and 22.6% (9.5, 56.9), were attributable to differences in GrimAge and DunedinPACE, respectively. DISCUSSION: Arsenic exposure was associated with older GrimAge and faster DunedinPACE measures of biological age. Furthermore, accelerated biological aging measured from DNA methylation accounted for a relevant fraction of As-associated risk for CVD, CVD mortality, and all-cause mortality in the SHS, supporting the role of As in accelerated aging. Research of the biological underpinnings can contribute to a better understanding of the role of aging in arsenic-related disease. [ABSTRACT FROM AUTHOR]

Pustular microbial mats in Shark Bay, Western Australia, are modern analogs of microbial systems that colonized peritidal environments before the evolution of complex life. To understand how these microbial communities evolved to grow and metabolize in the presence of various environmental stresses, the horizontal gene transfer (HGT) detection tool, MetaCHIP, was used to identify the horizontal transfer of genes related to stress response in 83 metagenome-assembled genomes from a Shark Bay pustular mat. Subsequently, maximum-likelihood phylogenies were constructed using these genes and their most closely related homologs from other environments in order to determine the likelihood of these HGT events occurring within the pustular mat. Phylogenies of several stress-related genes—including those involved in response to osmotic stress, oxidative stress and arsenic toxicity—indicate a potentially long history of HGT events and are consistent with these transfers occurring outside of modern pustular mats. The phylogeny of a particular osmoprotectant transport gene reveals relatively recent adaptations and suggests interactions between Planctomycetota and Myxococcota within these pustular mats. Overall, HGT phylogenies support a potentially broad distribution in the relative timing of the HGT events of stress-related genes and demonstrate ongoing microbial adaptations and evolution in these pustular mat communities. [ABSTRACT FROM AUTHOR]

The present study aims to determine the relationship between the concentration of arsenic in the groundwater of Hamadan province and the mortality rate due to various types of malignancies, congenital anomalies, diabetes mellitus and Alzheimer's. Mortality data due to various causes of death in Hamadan province were collected for five years (2016–2020). Sampling of drinking water was determined in the reference laboratory using polarography method. Poisson regression was used to investigate the relationship between arsenic level and the death rate due to various types of disease, at a significant level (p value < 0.05). According to the results of Poisson regression, among the various causes of death (N = 8042), Alzheimer's 5.94 (3.67–9.61), diabetes mellitus 4.05 (3.5–5.37), congenital malformations 2.98 (1.88–4.72), breast cancer 2.72 (1.56–4.71), leukemia 1.90 (1.24–2.92), stomach cancer 1.64 (1.28–2.10), Liver cancer 1.58 (1.58–2.30), other digestive organs 5.86 (3.38–10.16), meninges and brain cancer 1.57 (1.02–2.41) showed the highest relationship with arsenic contamination. The results of this study could be evidence for a positive and significant relationship between arsenic concentrations and mortality rates due to cancers, diabetes mellitus, Alzheimer disease, and congenital malformations. Therefore, it's necessary to use appropriate water treatment methods to remove arsenic at the source in contaminated areas. [ABSTRACT FROM AUTHOR]

Metalloid pollution, including arsenic poisoning, is a serious environmental issue, plaguing plant productivity and quality of life worldwide. Biochar, a carbon-rich material, has been known to alleviate the negative effects of environmental pollutants on plants. However, the specific role of biochar in mitigating arsenic stress in maize remains relatively unexplored. Here, we elucidated the functions of biochar in improving maize growth under the elevated level of sodium arsenate (Na2AsO4, AsV). Maize plants were grown in pot-soils amended with two doses of biochar (2.5% (B1) and 5.0% (B2) biochar Kg−1 of soil) for 5 days, followed by exposure to Na2AsO4 ('B1 + AsV'and 'B2 + AsV') for 9 days. Maize plants exposed to AsV only accumulated substantial amount of arsenic in both roots and leaves, triggering severe phytotoxic effects, including stunted growth, leaf-yellowing, chlorosis, reduced photosynthesis, and nutritional imbalance, when compared with control plants. Contrariwise, biochar addition improved the phenotype and growth of AsV-stressed maize plants by reducing root-to-leaf AsV translocation (by 46.56 and 57.46% in 'B1 + AsV' and 'B2 + AsV' plants), improving gas-exchange attributes, and elevating chlorophylls and mineral levels beyond AsV-stressed plants. Biochar pretreatment also substantially counteracted AsV-induced oxidative stress by lowering reactive oxygen species accumulation, lipoxygenase activity, malondialdehyde level, and electrolyte leakage. Less oxidative stress in 'B1 + AsV' and 'B2 + AsV' plants likely supported by a strong antioxidant system powered by biochar-mediated increased activities of superoxide dismutase (by 25.12 and 46.55%), catalase (51.78 and 82.82%), and glutathione S-transferase (61.48 and 153.83%), and improved flavonoid levels (41.48 and 75.37%, respectively). Furthermore, increased levels of soluble sugars and free amino acids also correlated with improved leaf relative water content, suggesting a better osmotic acclimatization mechanism in biochar-pretreated AsV-exposed plants. Overall, our findings provided mechanistic insight into how biochar facilitates maize's active recovery from AsV-stress, implying that biochar application may be a viable technique for mitigating negative effects of arsenic in maize, and perhaps, in other important cereal crops. Highlights: Maize developed significant growth defects under excessive arsenate (AsV) stress. Biochar addition decreased root AsV uptake and root-to-leaf AsV translocation. Biochar protected photosynthetic rate and pigment levels from AsV -stress. Biochar reduced AsV-caused oxidative damage by strengthening antioxidant defense. Biochar boosted osmoprotectant levels and nutrient uptake in AsV-stressed maize. [ABSTRACT FROM AUTHOR]

Fluoride (F) and arsenic (As) are two major contaminants of water and soil systems around the globe, causing potential toxicity to humans, plants, animals, and microbes. These contaminated soil systems can be restored by microorganisms that can tolerate toxic stress and provide rapid mineralization of soil, organic matter, and contaminants, using various tolerance mechanisms. Thus, the present study was undertaken with the arsenic hyper-tolerant bacterium Microbacterium paraoxydans strain IR-1 to determine its tolerance and toxicity to increasing doses of fluoride, either individually or in combination with arsenic, in terms of growth inhibition using a toxicity unit model. The minimum inhibitory concentration (MIC)and half maximal inhibitory concentration (IC50) values for fluoride increased, from 9 g/L to 11 g/L and from 5.91 ± 0.1 g/L to 6.32 ± 0.028 g/L, respectively, in the combination (F + As) group. The statistical comparison of observed and expected additive toxicities, with respect to toxicity unit (TU difference), using Student's t-test, was found to be highly significant (p < 0.001). This suggests the antagonistic effect of arsenic on fluoride toxicity to the strain IR-1. The unique stress tolerance of IR-1 ensures its survival as well as preponderance in fluoride and arsenic co-contaminated sites, thus paving the way for its possible application in the natural or artificial remediation of toxicant-exposed degraded soil systems. [ABSTRACT FROM AUTHOR]

Introduction: Approximately 200 million people worldwide are affected by arsenic toxicity emanating from the consumption of drinking water containing inorganic arsenic above the prescribed maximum contaminant level. The current investigation deals with the role of prenatal arsenic exposure in modulating the gut microbial community and functional pathways of the host. Method: 16S rRNA-based next-generation sequencing was carried out to understand the effects of in utero 0.04 mg/kg (LD) and 0.4 mg/kg (HD) of arsenic exposure. This was carried out from gestational day 15 (GD-15) until the birth of pups to understand the alterations in bacterial diversity. Results: The study focused on gestational exposure to arsenic and the altered gut microbial community at phyla and genus levels, along with diversity indices. A significant decrease in firmicutes was observed in the gut microbiome of mice treated with arsenic. Functional analysis revealed that a shift in genes involved in crucial pathways such as insulin signaling and non-alcoholic fatty liver disease pathways may lead to metabolic diseases in the host. Discussion: The present investigation may hypothesize that in utero arsenic exposure can perturb the gut bacterial composition significantly as well as the functional pathways of the gestationally treated pups. This research paves the way to further investigate the probable mechanistic insights in the field of maternal exposure environments, which may play a key role in epigenetic modulations in developing various disease endpoints in the progeny. [ABSTRACT FROM AUTHOR]

Inorganic arsenic in drinking water is prioritized as a top environmental contaminant by the World Health Organization, with over 230 million people potentially being exposed. Arsenic toxicity has been well documented and is associated with a plethora of human diseases, including diabetes, as established in numerous animal and epidemiological studies. Our previous study revealed that arsenic exposure leads to the inhibition of nuclear receptors, including LXR/RXR. To this end, FXR is a nuclear receptor central to glucose and lipid metabolism. However, limited studies are available for understanding arsenic exposure-FXR interactions. Herein, we report that FXR knockout mice developed more profound glucose intolerance than wild-type mice upon arsenic exposure, supporting the regulatory role of FXR in arsenic-induced glucose intolerance. We further exposed mice to arsenic and tested if GW4064, a FXR agonist, could improve glucose intolerance and dysregulation of hepatic proteins and serum metabolites. Our data showed arsenic-induced glucose intolerance was remarkably diminished by GW4064, accompanied by a significant ratio of alleviation of dysregulation in hepatic proteins (83%) and annotated serum metabolites (58%). In particular, hepatic proteins "rescued" from arsenic toxicity by GW4064 featured members of glucose and lipid utilization. For instance, the expression of PCK1, a candidate gene for diabetes and obesity that facilitates gluconeogenesis, was repressed under arsenic exposure in the liver, but revived with the GW4064 supplement. Together, our comprehensive dataset indicates FXR plays a key role and may serve as a potential therapeutic for arsenic-induced metabolic disorders. [ABSTRACT FROM AUTHOR]

BACKGROUND: Newborns can be exposed to inorganic arsenic (iAs) through contaminated drinking water, formula, and other infant foods. Epidemiological studies have demonstrated a positive association between urinary iAs levels and the risk of developing nonalcoholic fatty liver disease (NAFLD) among U.S. adolescents and adults. OBJECTIVES: The present study examined how oral iAs administration to neonatal mice impacts the intestinal tract, which acts as an early mediator for NAFLD. METHODS: Neonatal mice were treated with a single dose of iAs via oral gavage. Effects on the small intestine were determined by histological examination, RNA sequencing, and biochemical analysis. Serum lipid profiling was analyzed by fast protein liquid chromatography (FPLC), and hepatosteatosis was characterized histologically and biochemically. Liver X receptor-alpha (LXRα) knockout (퐿푥푟α-/-) mice and liver-specific activating transcription factor 4 (ATF4)-deficient (퐴푡푓 4Δ퐻푒푝) mice were used to define their roles in iAs-induced effects during the neonatal stage. RESULTS: Neonatal mice exposed to iAs via oral gavage exhibited accumulation of dietary fat in enterocytes, with higher levels of enterocyte triglycerides and free fatty acids. These mice also showed accelerated enterocyte maturation and a longer small intestine. This was accompanied by higher levels of liver-derived very low-density lipoprotein and low-density lipoprotein triglycerides, and a lower level of high-density lipoprotein cholesterol in the serum. Mice exposed during the neonatal period to oral iAs also developed hepatosteatosis. Compared with the control group, iAs-induced fat accumulation in enterocytes became more significant in neonatal 퐿푥푟α-/- mice, accompanied by accelerated intestinal growth, hypertriglyceridemia, and hepatosteatosis. In contrast, regardless of enterocyte fat accumulation, hepatosteatosis was largely reduced in iAs-treated neonatal 퐴푡푓 4Δ퐻푒푝 mice. CONCLUSION: Exposure to iAs in neonatal mice resulted in excessive accumulation of fat in enterocytes, disrupting lipid homeostasis in the serum and liver, revealing the importance of the gut–liver axis and endoplasmic reticulum stress in mediating iAs-induced NAFLD at an early age. [ABSTRACT FROM AUTHOR]

Arsenic toxicity, imposed mainly by arsenic-contaminated groundwater, is considered a critical threat to global communal health, as there is no specific and proven conventional therapy for chronic arsenic toxicity, i.e., arsenicosis, which is an insidious global public health menace affecting 50 countries. Alternative options should, therefore, be explored for the mitigation of arsenicosis. Literature survey reveals several natural compounds from plants possess significant protective efficacy against arsenic toxicity in chiefly preclinical and few clinical investigations. The studies on the ameliorative effects of plant-derived natural compounds against arsenic toxicity published in the last 25 years are collated. Fortyeight plant-based natural compounds possess alleviative effects on experimental arsenic-induced toxicity in animals, six of which have been reported to be clinically effective in humans. A potential nutraceutical or therapeutic candidate against arsenicosis for humans may thus be developed with the help of recent advancements in research in this area, along with the currently available treatments. [ABSTRACT FROM AUTHOR]

BACKGROUND: Neural tube defects (NTDs) affect >300,000 pregnancies worldwide annually. Few nongenetic factors, other than folate deficiency, have been identified that may provide intervenable solutions to reduce the burden of NTDs. Prenatal exposure to toxic metals [arsenic (As), cadmium (Cd), mercury (Hg), manganese (Mn) and lead (Pb)] may increase the risk of NTDs. Although a growing epidemiologic literature has examined associations, to our knowledge no systematic review has been conducted to date. OBJECTIVE: Through adaptation of the Navigation Guide systematic review methodology, we aimed to answer the question “does exposure to As, Cd, Hg, Mn, or Pb during gestation increase the risk of NTDs?” and to assess challenges to evaluating this question given the current evidence. METHODS: We selected available evidence on prenatal As, Cd, Hg, Mn, or Pb exposure and risk of specific NTDs (e.g., spina bifida, anencephaly) or all NTDs via a comprehensive search across MEDLINE, Embase, Web of Science, and TOXLINE databases and applied inclusion/exclusion criteria. We rated the quality and strength of the evidence for each metal. We applied a customized risk of bias protocol and evaluated the sufficiency of evidence of an effect of each metal on NTDs. RESULTS: We identified 30 studies that met our criteria. Risk of bias for confounding and selection was high in most studies, but low for missing data. We determined that, although the evidence was limited, the literature supported an association between prenatal exposure to Hg or Mn and increased risk of NTDs. For the remaining metals, the evidence was inadequate to establish or rule out an effect. CONCLUSION: The role of gestational As, Cd, or Pb exposure in the etiology of NTDs remains unclear and warrants further investigation in high-quality studies, with a particular focus on controlling confounding, mitigating selection bias, and improving exposure assessment. [ABSTRACT FROM AUTHOR]

Arsenic is one of the most abundant elements on earth. Arsenic, also called metalloid, is used as a raw material in many industries. Arsenic causes the acceleration of free radical production in the body and the resulting oxidative stress. In juvenile trout, the interactions of arsenic with metacomposition, biochemical analysis, and apoptosis stimuli were investigated. Results were demonstrated by several marker applications, including oxidative stress parameters, proinflammatory cytokine expressions, DNA damage, and apoptosis markers. In our study, arsenic was applied to juvenile trout (Oncorhynchus mykiss) at concentrations of 25, 50, and 75 mg/L for 96 h. After exposure, the brain tissues of the fish were collected and homogenized. SOD the GSH-Px, CAT, and MDA levels were determined by spectrophotometric methods in the supernatants from the brain tissues of the juvenile trout. Levels of NF-kB, TNF-α, IL-6, Nrf-2, GSH, caspase-3, AChE, and 8-OHdG were determined with an ELISA kit. When the brain tissues of the fish were examined after the study, it was found that the levels of NF-kB, TNF-α, IL-6, Nrf-2, Caspza-3, MDA, and 8-OHdG increased, and the levels of GSH, CAT, SOD, AChE, and GSH-Px decreased. It was found that oxidative stress occurred as a result of the effect of the heavy metal arsenic in the brain tissues of the fish after application. [ABSTRACT FROM AUTHOR]

Bamboo is nutritionally significant across the world because the shoots are high in calories and nutritional fiber but low in cholesterol. However, recent research has shown that bamboo shoots also contain a substantial quantity of heavy metals, including arsenic (As). Therefore, we explored whether the co-application of iron oxide nanoparticles (IONPs) and selenium nanoparticles (Se-NPs) would attenuate As toxicity in bamboo plants (Pleioblastus pygmaeus). A greenhouse experiment was performed to investigate plant responses to arsenic toxicity. Bamboo plants exposed to four levels of As (0, 10, 20, and 40 mg L−1) were foliar-sprayed with 60 mg L−1 of Se-NPs and 60 mg L−1 of IONPs alone and in combination. The data indicated that different As concentrations (10, 20, and 40 mg L−1) caused membrane damage and reactive oxide species (ROS) production in bamboo cells, characterized by H2O2, O2•−, MDA, and EL increasing by up to 47%, 54%, 57%, and 65%, respectively, in comparison with a control. The co-application of 60 mg L−1 of Se-NPs + IONP markedly improved the antioxidant enzyme activities (by 75% in SOD, 27% in POD, 52% in CAT, 37% in GR, and 38% in PAL), total flavonoid content (42%), phenolic content (36%), proline (44%), nitric oxide (59%), putrescine (Put) (85%), spermidine (Spd) (53%), relative water content (RWC) (36%), photosynthetic characteristics (27%) in net photosynthesis (Pn) (24% in the intercellular CO2 concentration (Ci), 39% in stomatal conductance (Gs), and 31% in chlorophyll pigments), and ultimately biomass indices and growth. The co-application of Se-NPs + IONPs with 10 and 20 mg L−1 of As raised the TI by 14% and 9% in the shoot and by 18% and 14% in the root, respectively. IONPs and Se-NPs reduced ROS, cell membrane lipoperoxidation, and electrolyte leakage, all contributing to the decrease in oxidative stress by limiting As uptake and translocation. In sum, Se-NPs and IONPs improved bamboo endurance, yet the most effective approach for increasing bamboo's ability to recover from As toxicity was the concurrent use of 60 mg L−1 of Se-NPs and 60 mg L−1 of IONPs. Our IONP and Se-NP data from single and combined applications offer novel knowledge in improving the tolerance mechanism against As exposure in Pleioblastus pygmaeus. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Patients that are taking Ayurvedic supplements have an increased risk of heavy metal toxicity. Lead, arsenic, and mercury are frequently identified in these supplements and can cause clinically significant toxicity. Clinicians should screen patients routinely for use of non‐pharmaceutical medications and supplements. [ABSTRACT FROM AUTHOR]

Exposure to inorganic arsenic remains a global public health problem. The liver is the main target organ, leading to arsenic-induced liver fibrosis. Phosphatase and tensin homology deleted on chromosome ten (PTEN) may participate in arsenic-induced liver fibrosis by regulating autophagy, but the exact mechanisms remain unclear. We established a mouse model of arsenic poisoning through their drinking water and a fibrosis model using the human hepatic stellate cell line LX-2 through NaAsO2 exposure for 24 h. Masson staining measured liver fibrosis. The cells were transfected with a PTEN overexpression plasmid. Western blot and qRT-PCR determined the levels of protein/mRNA expression. Fibrosis was evident in both the mouse model and arsenic-exposed LX-2 cells. NaAsO2 upregulated expression of autophagic markers microtubule-associated protein light chain A/B (LC3), recombinant human autophagy effector protein (Beclin-1), and hairy and enhancer of split homolog-1 (HES1), but downregulated PTEN. Alongside this, α-smooth muscle actin (α-SMA) expression was significantly upregulated by NaAsO2. PTEN overexpression altered NaAsO2-induced autophagy and downregulated LC3 and Beclin-1. While Notch1, HES1, α-SMA, and collagen I expression were all downregulated in the NaAsO2 groups. Therefore, PTEN overexpression might decrease autophagy and inhibit fibrosis progression caused by arsenic, and the NOTCH1/HES1 pathway is likely involved. [ABSTRACT FROM AUTHOR]

The World Health Organization (WHO) estimates that around ~150 million people in 70 different countries have been consuming water with arsenic levels higher than the recommended limit of 10 μg/L. Here we describe the concentrations of inorganic arsenic in drinking water in homes of pregnant women living in the province of Tacna, near the southern border of Peru. 161 pregnant women were enrolled in their second trimester of pregnancy. A total of 100mL drinking water was collected in each household from the source of most common use. Inorganic arsenic was categorized into 3 levels with a commercial kit. Thirty percent of women had drinking water ≤10 μg/L (the WHO recommended level), 35% had 25 μg/L, and 35% had greater than 50 μg/L. Low arsenic levels were found in the southernmost homes, supplied by groundwater, while high levels were found in the northern and metropolitan homes supplied by river water.

An 18-year-old man presented with palpitations and chest discomfort, and an electrocardiogram revealed supraventricular tachycardia. Further examination revealed tingling and numbness in his hands and feet, as well as hyperpigmented spots on his hands, back, and chest. Laboratory studies showed high levels of arsenic in his blood, and a diagnosis of chronic arsenic toxicity with cardiac, dermatological, and neurological manifestations was made. The patient's symptoms improved after discontinuing the homeopathic medications he had been taking. [Extracted from the article]