Oral arsenite exposure induces inflammation and apoptosis in pulmonary tissue: acute and chronic evaluation in young and adult mice.

Inorganic arsenic is a well-known environmental toxicant, and exposure to this metalloid is strongly linked with severe and extensive toxic effects in various organs including the lungs. In the present study, we aimed to investigate the acute and chronic effects of arsenite exposure on pulmonary tissue in young and adult mice. In brief, young and adult female Balb/C mice were exposed to 3 and 30 ppm arsenite daily via drinking water for 30 and 90 days. Subsequently, the animals were sacrificed and various histological and immunohistochemistry (IHC) analyses were performed using lung tissues. Our findings showed arsenite was found to cause dose-dependent pathological changes such as thickening of the alveolar septum, inflammatory cell infiltrations and lung fibrosis in young and adult mice. In addition, arsenite exposure significantly increased the expression of inflammatory markers NF-κB and TNF-α, indicating that arsenite-exposed mice suffered from severe lung inflammation. Moreover, the IHC analysis of fibrotic proteins demonstrated an increased expression of TGF-ß1, α-SMA, vimentin and collagen-I in the arsenite-exposed mice compared to the control mice. This was accompanied by apoptosis, which was indicated by the upregulated expression of caspase-3 in arsenite-exposed mice compared to the control. Adult mice were generally found to be more prone to arsenite toxicity during chronic exposure relative to their younger counterparts. Overall, our findings suggest that arsenite in drinking water may induce dose-dependent and age-dependent structural and functional impairment in the lungs through elevating inflammation and fibrotic proteins.

The Conundrum of the PFOA human half-life, an international collaboration.

The Steering Committee of the Alliance for Risk Assessment (ARA) opened a call for scientists interested in resolving what appeared to be a conundrum in estimating of the half-life of perfluorooctanoate (PFOA) in humans. An Advisory Committee was formed from nominations received and a subsequent invitation led to the development of three small independent working groups to review appropriate information and attempt a resolution. Initial findings were shared among these groups and a conclusion developed from the ensuing discussions. Many human observational studies have estimated the PFOA half-life. Most of these studies note the likely occurrence of unmonitored PFOA exposures, which could inflate values of the estimated PFOA half-life. Also, few of these studies estimated the half-life of PFOA isomers, the branched chains of which likely have shorter half-lives. This could deflate values of the estimated linear PFOA half-life. Fortunately, several studies informed both of these potential problems. The majority opinion of this international collaboration is that the studies striking the best balance in addressing some of these uncertainties indicate the likely central tendency of the human PFOA half-life is less than 2 years. The single best value appears to be the geometric mean (GM) of 1.3 years (Zhang et al., 2013, Table 3), based on a GM = 1.7 years in young females (n = 20) and GM = 1.2 years in males of all ages and older females (n = 66). However, a combined median value from Zhang et al. (2013) of 1.8 years also adds value to this range of central tendency. While the Collaboration found this study to be the least encumbered with unmonitored PFOA exposures and branched isomers, more studies of similar design would be valuable. Also valuable would be clarification around background exposures in other existing studies in case adjustments to half-life estimates are attempted.

Biotechnological Innovations from Ocean: Transpiring Role of Marine Drugs in Management of Chronic Disorders.

Marine drugs are abundant in number, comprise of a diverse range of structures with corresponding mechanisms of action, and hold promise for the discovery of new and better treatment approaches for the management of several chronic diseases. There are huge reserves of natural marine biological compounds, as 70 percent of the Earth is covered with oceans, indicating a diversity of chemical entities on the planet. The marine ecosystems are a rich source of bioactive products and have been explored for lead drug molecules that have proven to be novel therapeutic targets. Over the last 70 years, many structurally diverse drug products and their secondary metabolites have been isolated from marine sources. The drugs obtained from marine sources have displayed an exceptional potential in the management of a wide array of diseases, ranging from acute to chronic conditions. A beneficial role of marine drugs in human health has been recently proposed. The current review highlights various marine drugs and their compounds and role in the management of chronic diseases such as cancer, diabetes, neurodegenerative diseases, and cardiovascular disorders, which has led to the development of new drug treatment approaches.

Molecular Mechanism of Arsenic-Induced Neurotoxicity including Neuronal Dysfunctions.

Arsenic is a key environmental toxicant having significant impacts on human health. Millions of people in developing countries such as Bangladesh, Mexico, Taiwan, and India are affected by arsenic contamination through groundwater. Environmental contamination of arsenic leads to leads to various types of cancers, coronary and neurological ailments in human. There are several sources of arsenic exposure such as drinking water, diet, wood preservatives, smoking, air and cosmetics, while, drinking water is the most explored route. Inorganic arsenic exhibits higher levels of toxicity compared its organic forms. Exposure to inorganic arsenic is known to cause major neurological effects such as cytotoxicity, chromosomal aberration, damage to cellular DNA and genotoxicity. On the other hand, long-term exposure to arsenic may cause neurobehavioral effects in the juvenile stage, which may have detrimental effects in the later stages of life. Thus, it is important to understand the toxicology and underlying molecular mechanism of arsenic which will help to mitigate its detrimental effects. The present review focuses on the epidemiology, and the toxic mechanisms responsible for arsenic induced neurobehavioral diseases, including strategies for its management from water, community and household premises. The review also provides a critical analysis of epigenetic and transgenerational modifications, mitochondrial oxidative stress, molecular mechanisms of arsenic-induced oxidative stress, and neuronal dysfunction.

Applications of Adductomics in Chemically Induced Adverse Outcomes and Major Emphasis on DNA Adductomics: A Pathbreaking Tool in Biomedical Research.

Adductomics novel and emerging discipline in the toxicological research emphasizes on adducts formed by reactive chemical agents with biological molecules in living organisms. Development in analytical methods propelled the application and utility of adductomics in interdisciplinary sciences. This review endeavors to add a new dimension where comprehensive insights into diverse applications of adductomics in addressing some of society's pressing challenges are provided. Also focuses on diverse applications of adductomics include: forecasting risk of chronic diseases triggered by reactive agents and predicting carcinogenesis induced by tobacco smoking; assessing chemical agents' toxicity and supplementing genotoxicity studies; designing personalized medication and precision treatment in cancer chemotherapy; appraising environmental quality or extent of pollution using biological systems; crafting tools and techniques for diagnosis of diseases and detecting food contaminants; furnishing exposure profile of the individual to electrophiles; and assisting regulatory agencies in risk assessment of reactive chemical agents. Characterizing adducts that are present in extremely low concentrations is an exigent task and more over absence of dedicated database to identify adducts is further exacerbating the problem of adduct diagnosis. In addition, there is scope of improvement in sample preparation methods and data processing software and algorithms for accurate assessment of adducts.

In Vitro Phytochemical Screening, Cytotoxicity Studies of Curcuma longa Extracts with Isolation and Characterisation of Their Isolated Compounds.

The Curcuma longa plant is endowed with multiple traditional and therapeutic utilities and is here explored for its phytochemical constituents and cytotoxic potential. Turmeric rhizomes were extracted from three different solvents and screened for the presence of different phytochemical constituents, observation of which indicated that the polar solvents favoured extraction of greater versatile phytochemical constituents. These extracts were investigated for their cytotoxic potential by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on three different of cell lines including SCC-29B (oral cancer cell line), DU-145 (prostate cancer cell line) and the Vero cell line (healthy cell line/non-cancerous cell line). This assay was performed by taking three extracts from isolated curcuminoids and a pure bioactive compound bisdemethoxycurcumin (BD). Bisdemethoxycurcumin was isolated from curcuminoids and purified by column and thin-layer chromatography, and its structural characterisation was performed with different spectroscopic techniques such as FTIR, NMR (1H Proton and 13C Carbon-NMR) and LC-MS. Amongst the extracts, the ethanolic extracts exhibited stronger cytotoxic potential against the oral cancer cell line (SCC-29B) with an IC50value of 11.27 µg/mL, and that this was too low of a cytotoxicity against the Vero cell line. Although, curcuminoids have also shown a comparable cytotoxic potential against SCC-29B (IC50 value 16.79 µg/mL), it was not as potent against the ethanolic extract, and it was even found to be cytotoxic against healthy cell lines at a very low dose. While considering the isolated compound, bisdemethoxycurcumin, it also possessed a cytotoxic potential against the prostate cancer cell line (DU-145) (IC50 value of 93.28 µg/mL), but was quite safe for the healthy cell line in comparison to doxorubicin.

Reproductive and Developmental Effects of Sex-Specific Chronic Exposure to Dietary Arsenic in Zebrafish (Danio rerio).

The present study investigated the reproductive and developmental effects of sex-specific chronic exposure to dietary arsenic in zebrafish. Adult zebrafish (Danio rerio) were exposed to environmentally realistic doses of arsenic via diet [0 (control; no added arsenic), 30 (low), 60 (medium), and 100 (high) µg/g dry weight, as arsenite] for 90 days. Following exposure, arsenic-exposed females from each dietary treatment were mated with control males, and similarly, arsenic-exposed males from each dietary treatment were mated with control females. In females, arsenic exposure resulted in a dose-dependent decrease in reproductive performance (fecundity, fertilization success, and hatching success). Moreover, a dose-dependent increase in developmental toxicity (larval deformities and larval mortality) was observed with maternal exposure to arsenic. In contrast, in males, arsenic exposure also induced similar reproductive and developmental toxicity; however, the adverse effects were mainly evident only in the medium and high dietary arsenic treatment groups. We also examined the sex-specific effects of dietary arsenic exposure on the expression of genes that regulate the hypothalamus-pituitary-gonadal-liver (HPG-L) axis in fish. The gene expression results indicated the downregulation of HPG-L axis genes in females irrespective of the arsenic treatment dose; however, the reduced expression of HPG-L axis genes in males was recorded only in the medium and high arsenic treatment groups. These observations suggest that chronic arsenic exposure in either females or males causes reproductive and developmental toxicity in zebrafish. However, these toxic effects are markedly higher in females than in males. Our results also suggest that arsenic can act as an endocrine disruptor and mediate reproductive and developmental toxicity by disrupting the HPG-L axis in zebrafish.

Pulmonary fibrotic response to inhalation of ZnO nanoparticles and toluene co-exposure through directed flow nose only exposure chamber.

The increasing use of Zinc Oxide nanoparticles (ZnONPs) in paint industry is not supplemented with adequate toxicology data. This report focuses on the fibrogenic toxicity caused due to co-exposure of ZnONPs and toluene in male Wistar rats, exposed for 28 days, through directed flow nose only exposure chamber. The rats were grouped as air control, toluene control (200 ppm), zinc oxide control (10 mg/m(3)), low dose co-exposed (5 mg/m(3) ZnO and 200 ppm of toluene) and high dose co-exposed (10 mg/m(3) of ZnO and 200 ppm of toluene). Our study demonstrates that co-exposure of ZnONPs and toluene (as in paint industry), even at their respective permissible exposure level (5 mg/m(3) for ZnO and 200 ppm for toluene) have the potential to produce a progressive inflammatory and fibrotic response in the alveolar tissues of the lungs. We observed a significant increase in inflammatory markers in BAL fluid and elevated malondialdehyde (MDA) levels with lower levels of intracellular reduced glutathione (GSH) in lungs of rats of co-exposed group. Significant increase in the levels of pro-inflammatory mediators (IL-6, Ikßα, Cox-II, p-NF-κB) in lung tissues also indicated pulmonary damage. To best of our knowledge this is the first study which highlights the toxicity of co-exposed ZnO NPs and toluene.

Lung fibrosis: Post-COVID-19 complications and evidences.

BACKGROUND: COVID 19, a lethal viral outbreak that devastated lives and the economy across the globe witnessed non-compensable respiratory illnesses in patients. As been evaluated in reports, patients receiving long-term treatment are more prone to acquire Pulmonary Fibrosis (PF). Repetitive damage and repair of alveolar tissues increase oxidative stress, inflammation and elevated production of fibrotic proteins ultimately disrupting normal lung physiology skewing the balance towards the fibrotic milieu. AIM: In the present work, we have discussed several important pathways which are involved in post-COVID PF. Further, we have also highlighted the rationale for the use of antifibrotic agents for post-COVID PF to decrease the burden and improve pulmonary functions in COVID-19 patients. CONCLUSION: Based on the available literature and recent incidences, it is crucial to monitor COVID-19 patients over a period of time to rule out the possibility of residual effects. There is a need for concrete evidence to deeply understand the mechanisms responsible for PF in COVID-19 patients.

Examining the subchronic (28-day) effects of aqueous Cd-BaP co-exposure on detoxification capacity and cardiac function in adult zebrafish (Danio rerio).

The present study aimed to examine the effects of environmentally relevant concentrations of cadmium (Cd) and Benzo[a]Pyrene (BaP) in the adult zebrafish (Danio rerio). To this end, fish were exposed to either 1 or 10 µg/L Cd or 0.1 or 1 µg/L BaP in isolation, or a co-exposure containing a mixture of the two toxicants. Our results showed extensive modulation of the expression of key antioxidant genes (GPx, SOD1, catalase), detoxifying genes (MT1, MT2, CYP1A1) and a stress biomarker (HSP70) differing between control, single toxicant groups and co-exposure groups. We additionally carried out histopathological analysis of the gills, liver, and hearts of exposed animals, noting no differences in tissue necrosis or apoptosis. Finally, we carried out ultrasonographic analysis of cardiac function, noting a significant decrease of E-wave peak velocity and end diastolic volume in exposed fish. This in turn was accompanied by a decrease in stroke volume and ejection fraction, but not cardiac output in co-exposed fish. The present study is the first to demonstrate that a subchronic aqueous exposure to a Cd-BaP mixture can extensively modulate detoxification capacity and cardiac function in adult zebrafish in a tissue-specific manner.

Chronic dietary exposure to arsenic at environmentally relevant concentrations impairs cognitive performance in adult zebrafish (Danio rerio) via oxidative stress and dopaminergic dysfunction.

The current study was designed to evaluate the effects of chronic dietary arsenic exposure on the cognitive performance of adult zebrafish and uncover probable pathways by which arsenic mediates such neurotoxic effects. Adult zebrafish were treated with 3 different dietary arsenic concentrations (30, 60, and 100 µg/g dry weight (dw), as arsenite) in addition to control for 60 days. A latent learning paradigm, which employs a complex maze, was used to assess the cognitive performance of fish. Our results demonstrated that dietary treatment with arsenic, especially at medium (60 µg/g dw) and high (100 µg/g dw) exposure dose levels, significantly impaired the performance of fish in various latent learning tasks evaluated in the present study. Concomitant with cognitive dysfunction, chronic dietary exposure to arsenic was also found to increase arsenic accumulation and dopamine levels, and induce oxidative stress (reduced thiol redox, increased lipid peroxidation and expression of antioxidant enzyme genes) in the brain of zebrafish in a dose-dependent manner. Dopaminergic system in the brain is known to play a critical role in regulating cognitive behaviours in fish, and our observations suggested that chronic dietary treatment with medium and high arsenic doses leads to significant alterations in the expression of genes involved in dopamine signaling (dopamine receptors), synthesis (thyroxine hydroxylase) and metabolism (monoamine oxidase) in the zebrafish brain. Moreover, we also recorded significant downregulation of genes such as the brain-derived neurotrophic factor (BDNF) and ectonucleotidases (entpd2_mg, entpd2_mq, and 5'-nucleotidase), which are critical for learning and memory functions, in the zebrafish brain following chronic dietary exposure to arsenic. Overall, the present study suggests that chronic environmentally relevant dietary exposure to arsenic can impair the cognitive performance in zebrafish, essentially by inducing oxidative stress and disrupting the dopaminergic neurotransmission in the brain.

Melatonin Attenuates Extracellular Matrix Accumulation and Cardiac Injury Manifested by Copper.

Copper-induced cardiac injury is not widely reported in spite of its ability to cause oxidative damage and tissue injury. Structural and morphological changes in the cardiac tissue are triggered via oxidative stress and inflammatory responses following copper exposure. The varied and unavoidable exposure of copper through contaminated food and water warrants a safe and effective agent against its harmful effects. Since the heart is highly sensitive to changes in the redox balance, the present study was undertaken to examine the protective effects of melatonin against copper-induced cardiac injury. Sprague Dawley (SD) rats were exposed to 100 ppm of elemental copper via drinking water for 4 months. The cardiac tissue was evaluated for various biochemical, histological, and protein expression studies. Animals exposed to copper exhibited induced oxidative stress and cardiac injury compared to normal control. To this end, we found that melatonin treatment ameliorated copper-induced alterations in tissue oxidative variables like ROS, nitrate, MDA, and GSH. In addition, histological examinations unravelled decreased cardiac muscle dilation, atrophy, and cardiomyopathy in melatonin-treated rats. Furthermore, melatonin-treated rats were associated with reduced tissue copper levels, collagen deposition, α-SMA, and increased HO-1 expression as compared to rats exposed exclusively to copper. Moreover, the levels of NF-κB and cardiac markers such as CK-MB, cTnI, and cTnT were found to be decreased in the melatonin-treated animals. Altogether, melatonin-triggered increase in antioxidant capacity resulting in reduced aggregation of ECM components demonstrates the therapeutic potential of melatonin in the treatment of cardiac injury and tissue fibrosis.

Mitochondrial Dysfunction: A Cellular and Molecular Hub in Pathology of Metabolic Diseases and Infection.

Mitochondria are semiautonomous doubly membraned intracellular components of cells. The organelle comprises of an external membrane, followed by coiled structures within the membrane called cristae, which are further surrounded by the matrix spaces followed by the space between the external and internal membrane of the organelle. A typical eukaryotic cell contains thousands of mitochondria within it, which make up 25% of the cytoplasm present in the cell. The organelle acts as a common point for the metabolism of glucose, lipids, and glutamine. Mitochondria chiefly regulate oxidative phosphorylation-mediated aerobic respiration and the TCA cycle and generate energy in the form of ATP to fulfil the cellular energy needs. The organelle possesses a unique supercoiled doubly stranded mitochondrial DNA (mtDNA) which encodes several proteins, including rRNA and tRNA crucial for the transport of electrons, oxidative phosphorylation, and initiating genetic repair processors. Defects in the components of mitochondria act as the principal factor for several chronic cellular diseases. The dysfunction of mitochondria can cause a malfunction in the TCA cycle and cause the leakage of the electron respiratory chain, leading to an increase in reactive oxygen species and the signaling of aberrant oncogenic and tumor suppressor proteins, which further alter the pathways involved in metabolism, disrupt redox balance, and induce endurance towards apoptosis and several treatments which play a major role in developing several chronic metabolic conditions. The current review presents the knowledge on the aspects of mitochondrial dysfunction and its role in cancer, diabetes mellitus, infections, and obesity.

Arsenic Exposure and Amyloid Precursor Protein Processing: A Focus on Alzheimer's Disease.

BACKGROUND: Arsenic is present in above permissible safe limits in groundwater, soil, and food, in various areas of the world. This is increasing exposure to humankind and affecting health in various ways. Alternation in cognition is one among them. Epidemiological research has reflected the impact of arsenic exposure on children in the form of diminished cognition. AIMS: Considering this fact, the present study reviewed the impact of arsenic on amyloid precursor protein, which is known to cause one of the commonest cognitive disorders such as Alzheimer's disease. METHODS: The present study reviews the arsenic role in the generation of amyloid-beta from its precursor that leads to Alzheimer's disease through the published article from Pubmed and Scopus. DESCRIPTION: According to the findings, regular, long-term exposure to arsenic beginning in infancy changes numerous arsenic level-regulating regions in the rat brain, which are related to cognitive impairments. Arsenic also affects the BBB clearance route by increasing RAGE expression. Arsenic triggers the proamyloidogenic pathway by increasing APP expression and subsequently, its processing by ß-secretase and presenilin. Arsenic also affects mitochondrial dynamics, DNA repair pathway and epigenetic changes. The mechanism behind all these changes is explained in the present review article. CONCLUSION: A raised level of arsenic exposure affects the amyloid precursor protein, a factor for the early precipitation of Alzheimer's disease.

Neuroprotective potential of saroglitazar in 6-OHDA induced Parkinson's disease in rats.

Parkinson's disease (PD) is a neurodegenerative disorder that affects 2%-3% of the population worldwide. Clinical presentation of PD includes motor and non-motor symptoms. The interplay between pathogenic factors such as increased oxidative stress, neuroinflammation, mitochondrial dysfunction and apoptosis are responsible for neurodegeneration in PD. Intrastriatal administration of 6-hydroxy dopamine (6-OHDA) in rat brain provoked oxidative and nitrosative stress by decreasing endogenous antioxidants such as superoxide dismutase, catalase, glutathione, glutathione peroxidase and glutathione reductase. Consequently, interleukin-6, tumour necrosis-α, interferon-γ and cyclooxygenase-2 mediated neuroinflammation leads to mitochondrial dysfunction, involving inhibition of complex-II and IV activities, followed by apoptosis and degeneration of striatal dopaminergic neurons. Degeneration of dopaminergic neurons resulted in reduced dopamine turnover, consequently induced behavioural abnormalities in rats. Activation of peroxisome proliferator-activated receptors (PPARs) have protective role in PD by modulating response of antioxidant enzymes, neuroinflammation and apoptosis in various animal models of PD. Saroglitazar (SG) being dual PPAR-α/γ agonist activates both PPAR-α and PPAR-γ receptors and provide neuroprotection by reducing oxidative stress, neuroinflammation, mitochondrial dysfunction and apoptosis of dopaminergic cells in 6-OHDA induced PD in rats. Thereby, SG restored striatal histopathological damage and dopamine concentration in rat striatum, and behavioural alterations in rats. Thus, SG proved neuroprotective effects in rat model of PD. Potential benefits of SG in rat model of PD advocates to consider it for further preclinical and clinical evaluation.

Geraniol protects hippocampal CA1 neurons and improves functional outcomes in global model of stroke in rats.

Geraniol (GE), an acyclic monoterpene, is a chief constituent of essential oils of herbs and fruits. It possesses diverse pharmacological actions like antioxidant, anti-inflammatory, anti-apoptotic, and anti-parkinson. However, its neuroprotective potential in stroke is yet to be explored at large. The present study evaluated the neuroprotective potential of GE against the global model of cerebral ischemia/reperfusion (I/R)-injury in rats. Bilateral common carotid artery (BCCA) occlusion for 30 min followed by 7 days of reperfusion caused varied biochemical/enzymatic alterations viz. increase in levels of lipid peroxidation (LPO), nitric oxide (NO), xanthine oxidase (XO), and decrease in the levels of cerebroprotectives like superoxide dismutase (SOD), catalase (CAT), total thiols, and glutathione (GSH). GE-pretreatment markedly reversed these changes and restored the levels of protective enzymatic and non-enzymatic antioxidants near to normal compared to I/R group. Besides, GE treatment showed marked improvement in anxiety-related behavior and neuronal deficits in animals subjected to I/R injury. Moreover, 2,3,5-triphenyl tetrazolium chloride (TTC)-stained rat brain coronal sections and histopathological studies revealed neuronal protection against I/R-injury, as evidenced by a reduction in infarct area (%) and an increase in hippocampal CA1 neuronal density in the GE-treated groups. The results of this study revealed that GE exhibited potential neuroprotective activity by reducing oxidative stress and infarction area, and protecting hippocampal CA1 neurons against I/R-injury in the global stroke model in rats.

Arsenic causing gallbladder cancer disease in Bihar.

In recent times Gallbladder cancer (GBC) incidences increased many folds in India and are being reported from arsenic hotspots identified in Bihar. The study aims to establish association between arsenic exposure and gallbladder carcinogenesis. In the present study, n = 200 were control volunteers and n = 152 confirmed gallbladder cancer cases. The studied GBC patient's biological samples-gallbladder tissue, gallbladder stone, bile, blood and hair samples were collected for arsenic estimation. Moreover, n = 512 gallbladder cancer patients blood samples were also evaluated for the presence of arsenic to understand exposure level in the population. A significantly high arsenic concentration (p < 0.05) was detected in the blood samples with maximum concentration 389 µg/L in GBC cases in comparison to control. Similarly, in the gallbladder cancer patients, there was significantly high arsenic concentration observed in gallbladder tissue with highest concentration of 2166 µg/kg, in gallbladder stones 635 µg/kg, in bile samples 483 µg/L and in hair samples 6980 µg/kg respectively. Moreover, the n = 512 gallbladder cancer patient's blood samples study revealed very significant arsenic concentration in the population of Bihar with maximum arsenic concentration as 746 µg/L. The raised arsenic concentration in the gallbladder cancer patients' biological samples-gallbladder tissue, gallbladder stone, bile, blood, and hair samples was significantly very high in the arsenic exposed area. The study denotes that the gallbladder disease burden is very high in the arsenic exposed area of Bihar. The findings do provide a strong link between arsenic contamination and increased gallbladder carcinogenesis.

Maternal exposure to bisphenol S induces neuropeptide signaling dysfunction and oxidative stress in the brain, and abnormal social behaviors in zebrafish (Danio rerio) offspring.

Recent studies show that bisphenol S (BPS) induces multiple adverse effects in exposed organisms; however, the maternal effects of BPS exposure remain poorly understood. Here, we expose adult female zebrafish to environmentally relevant concentrations of BPS (0, 1, 10, 30 µg/L) and 1 µg/L of 17-ß-estradiol (E2) as a positive control for 60 days. Females were then paired with BPS-unexposed males and their offspring were raised in control water for 6 months. Maternal exposure to BPS was found to alter social behavior and anxiety response in a dose-specific manner in male offspring. Group preferences and social cohesion were significantly reduced by maternal exposure to 1 and 10 µg/L BPS, respectively. Additionally, maternal exposure to 1 and 30 µg/L BPS and E2 decreased offspring stress responses during the novel tank test. The impaired social behavior was associated with elevated arginine-vasotocin (AVT) level as well as with the altered expression of genes involved in AVT signaling pathway (AVT, avpr1aa) and enzymatic antioxidant genes (cat and Mn-sod) in the brain. Collectively, these results suggest that maternal exposure to environmentally relevant concentrations of BPS alters social behavior in zebrafish offspring, which is likely mediated by oxidative stress and disruption of neuropeptide signaling pathways in the brain.

Contemporary Comprehensive Review on Arsenic-Induced Male Reproductive Toxicity and Mechanisms of Phytonutrient Intervention.

Arsenic (As) is a poisonous metalloid that is toxic to both humans and animals. Drinking water contamination has been linked to the development of cancer (skin, lung, urinary bladder, and liver), as well as other disorders such as diabetes and cardiovascular, gastrointestinal, neurological, and developmental damage. According to epidemiological studies, As contributes to male infertility, sexual dysfunction, poor sperm quality, and developmental consequences such as low birth weight, spontaneous abortion, and small for gestational age (SGA). Arsenic exposure negatively affected male reproductive systems by lowering testicular and accessory organ weights, and sperm counts, increasing sperm abnormalities and causing apoptotic cell death in Leydig and Sertoli cells, which resulted in decreased testosterone synthesis. Furthermore, during male reproductive toxicity, several molecular signalling pathways, such as apoptosis, inflammation, and autophagy are involved. Phytonutrient intervention in arsenic-induced male reproductive toxicity in various species has received a lot of attention over the years. The current review provides an in-depth summary of the available literature on arsenic-induced male toxicity, as well as therapeutic approaches and future directions.