Prevalence of Extended-Spectrum ß-Lactamases (ESBLs) Producing Aeromonas spp. Isolated from Lamellidens marginalis (Lamark, 1819) of Sewage-Fed Wetland: A Phenotypic and Genotypic Approach.

The global rise of zoonotic bacteria resistant to multiple antimicrobial classes and the growing occurrence of infections caused by Aeromonas spp. resistant to ß-lactam antibiotics pose a severe threat to animal and human health. However, the contribution of natural environments, particularly aquatic ecosystems, as ideal settings for the development and spread of antimicrobial resistance (AMR) is a key concern. Investigating the phenotypic antibiotic resistance and detection of ß-lactamase producing Aeromonas spp. in Lamellidens marginalis, which inhabit all freshwater ecosystems of the Indian subcontinent, is essential for implications in monitoring food safety and drug resistance. In the present investigation, 92 isolates of Aeromonas spp. were recovered from 105 bivalves and screened for their antimicrobial resistance patterns. In vitro antibiotic resistance profiling showed a higher Multiple Antibiotic Resistance (MAR) index of 0.8 with the highest resistance against ampicillin/sulbactam (82%), while 58, 44, 39 and 38% of the isolates were resistant to cephalothin, erythromycin, cefoxitin and imipenem, respectively. PCR results revealed that these isolates carried the blaTEM gene (94%), which was followed by the blaCTX-M gene (51%) and the blaSHV gene (45%). A combination of blaSHV, blaCTX-M, and blaTEM genes was found in 17% of the isolates, indicating the presence of all three resistance genes. This is the first investigation which highlights the importance of multidrug-resistant Aeromonas spp. in L. marginalis. The identification of extended-spectrum-ß-lactamases (ESBLs) genes demand the necessity of continuous surveillance and systematic monitoring, considering its potential health risks for both animals and human beings.

Trophic transfer patterns of arsenic in freshwater ecosystem layers in arsenic-endemic Ganges Delta and its potential human health risk.

Arsenic (As) is a toxic environmental contaminant with global public health concern. In aquatic ecosystems, the quantification of total As is restricted chiefly to the individual organisms. The present study has quantified the total As in different trophic layers (sediment-water-phytoplankton-periphyton-zooplankton-fish-gastropod-hydrophytes) of lentic freshwater ecosystems. As transfer pathways quantifying the transmission rate across trophic-level compartmental route were delineated using a novel model-based approach along with its potential contamination risk to humans. Lentic water bodies from Indo-Gangetic region, a core area of groundwater As, were selected for the present investigation. The study revealed that among the lower biota, zooplankton were the highest accumulator of total As (5554-11,564 µg kg-1) with magnification (rate = 1.129) of the metalloid, followed by phytoplankton (2579-6865 µg kg-1) and periphytic biofilm (1075 to 4382 µg kg -1). Muscle tissue of zooplanktivore Labeo catla is found to store higher As (80-115 µg kg-1 w.w.) compared to bottom-dwelling omnivore Cirrhinus mrigala (58-92 µg kg-1 w.w.). Whereas, Amblypharyngodon mola has accumulated higher As (203-319 µg kg-1 w.w.) than Puntius sophore (30-98 µg kg-1 w.w.) that raised further concern. The hepatic concentration indicated arsenic-mediated stress based on As stress index (threshold value = 1). Mrigal and Mola showed significant biomagnification among fishes while biodiminution was observed in Catla, Bata, Rohu and Punti. All the studied fishes were under the arsenic mediated stress. In the 'sediment-water-periphytic biofilm-gastropod' compartment, the direct grazing accumulation was higher (rate = 0.618) than the indirect path (rate = 0.587). Stems of edible freshwater macrophytes accumulated lesser As (32-190 µg kg-1 d.w.) than roots (292-946 µg kg-1 d.w.) and leaves (62-231 µg kg-1 d.w.). The target cancer risk (TCR) revealed a greater concern for adults consuming edible macrophyte regularly. Similarly, the varied level of target hazard quotient and TCR for adults consuming fishes from these waterbodies further speculated significant health concerns. The trophic transfer rate of environmental As in soil-water-biota level at an increasing trophic guild and consumer risk analysis have been unravelled for the first time in the Indo-Gangetic plains, which will be helpful for the strategic mitigation of As contamination.

Microbiome analysis reveals potential for modulation of gut microbiota through polysaccharide-based prebiotic feeding in Oreochromis niloticus (Linnaeus, 1758).

Characterization and functional profiling of the gut microbiota are essential for guiding nutritional interventions in fish and achieving favorable host-microbe interactions. Thus, we conducted a 30 days study to explore and document the gut microbial community of O. niloticus, as well as to evaluate the effects of a polysaccharide-based prebiotics with 0.5% and 0.75% Aloe vera extract on the gut microbiome through genomic analysis. The V3-V4 region of 16S rRNA was amplified and sequenced using Illumina HiSeq 2500, resulting in 1,000,199 reads for operational taxonomic unit (OTU) identification. Out of 8,894 OTUs, 1,181 were selected for further analysis. Our results revealed that Planctomycetes, Firmicutes, Proteobacteria, Verrucomicrobia, Actinobacteria, and Fusobacteria were the dominant phyla in both control and treatment samples. Higher doses of prebiotics were found to improve Planctomycetes and Firmicutes while decreasing Proteobacteria and Verrucomicrobia. We observed increasing trends in the abundance of Bacilli, Bacillaceae, and Bacillus bacteria at the class, family, and genus levels, respectively, in a dose-dependent manner. These findings were consistent with the conventional colony count data, which showed a higher prevalence of Bacillus in prebiotic-supplemented groups. Moreover, predicted functional analysis using PICRUSt indicated a dose-dependent upregulation in glycolysis V, superpathway of glycol metabolism and degradation, glucose and xylose degradation, glycolysis II, and sulfoglycolysis pathways. Most of the energy, protein, and amino acid synthesis pathways were upregulated only at lower doses of prebiotic treatment. Our findings suggest that the gut microbiome of O. niloticus can be optimized through nutritional interventions with plant-based polysaccharides for improved growth performance in commercial fish.

Peeping into Mitochondrial Diversity of Andaman Goats: Unveils Possibility of Maritime Transport with Diversified Geographic Signaling.

Andaman and Nicobar Islands, a part of South-East Asia, is enriched with the presence of native breeds of livestock (cattle, pig, goat) and poultry. There are two native goat breeds, viz., Andaman local goat and Teressa goat in Andaman and Nicobar Islands. However, to date, the origin and genetic makeup of these two breeds have not been detailed. Therefore, the present study describes the genetic makeup of Andaman goats through analysis of mitochondrial D-loop sequence for sequence polymorphism, phylogeographical signaling and population expansion events. The genetic diversity of the Teressa goat was less compared to the Andaman local goat due to its sole presence on Teressa Island. Out of 38 well-defined haplotypes of Andaman goats, the majority of haplotypes belonged to haplogroup A followed by haplogroup B and haplogroup D. The result of mismatch distribution and neutrality tests indicated no population expansion event of haplogroup A and B. Finally, based on poor geographical signaling, we hypothesize that Andaman goats have been imported to these Islands either through multidirectional diffusion or unidirectional diffusion. We justify our hypothesis of multidirectional diffusion on the basis of observation of the haplotype and nucleotide diversity of Andaman goats. Simultaneously, the probability of unidirectional diffusion of goats in these islands from the Indian subcontinent in different spells of domestication events through maritime routes cannot be ignored.

Immunomodulatory Potency of Eclipta alba (Bhringaraj) Leaf Extract in Heteropneustes fossilis against Oomycete Pathogen, Aphanomyces invadans.

Aphanomyces invadans is an aquatic oomycete pathogen and the causative agent of epizootic ulcerative syndrome (EUS) in fresh and brackish water fish, which is responsible for severe mortalities and economic losses in aquaculture. Therefore, there is an urgent need to develop anti-infective strategies to control EUS. An Oomycetes, a fungus-like eukaryotic microorganism, and a susceptible species, i.e., Heteropneustes fossilis, are used to establish whether an Eclipta alba leaf extract is effective against the EUS-causing A. invadans. We found that treatment with methanolic leaf extract, at concentrations between 50-100 ppm (T4-T6), protects the H. fossilis fingerlings against A. invadans infection. These optimum concentrations induced anti-stress and antioxidative response in fish, marked by a significant decrease in cortisol and elevated levels of superoxide dismutase (SOD) and catalase (CAT) levels in treated animals, as compared with the controls. We further demonstrated that the A. invadans-protective effect of methanolic leaf extract was caused by its immunomodulatory effect and is linked to the enhanced survival of fingerlings. The analysis of non-specific and specific immune factors confirms that methanolic leaf extract-induced HSP70, HSP90 and IgM levels mediate the survival of H. fossilis fingerlings against A. invadans infection. Taken together, our study provides evidence that the generation of anti-stress and antioxidative responses, as well as humoral immunity, may play a role in protecting H. fossilis fingerlings against A. invadans infection. It is probable that E. alba methanolic leaf extract treatment might become part of a holistic strategy to control EUS in fish species.

Co-Prevalence of Virulence and Pathogenic Potential in Multiple Antibiotic Resistant Aeromonas spp. from Diseased Fishes with In Silico Insight on the Virulent Protein Network.

Aeromonas species exhibit widespread presence in food, poultry, and aquaculture. They are major multi-drug-resistant fish pathogens. This study aims to identify Aeromonas species harbouring virulence genes aerolysin, flagellin, and lipase from diseased fishes of Assam wetlands with association with antibiotic resistance and in vivo pathogenicity. One hundred and thirty-four Aeromonas strains were isolated and thirty representative species identified using genus-specific 16S rRNA gene amplification. A. veronii was most prevalent (53.7%) followed by A. hydrophila (40.2%), A. caviae (4.47%), and A. dhakensis (1.49%). Ninety percent (90%) of strains harboured at least one of the studied virulence genes: aerA (73.3%), lip (46.6%), and flaA (26.6%). The highest multiple antibiotic resistance (MAR) index 0.8 corresponded to A. hydrophila DBTNE1 (MZ723069), containing all the studied genes. The lowest LD50 values (1.6 × 106 CFU/fish) corresponded to isolates having both aerA and lip. ß-lactams showed utmost resistance and lowest for aminoglycosides. There was a significant (p < 0.05) Pearson chi-square test of association between the occurrence of virulence and antibiotic resistance. The in silico protein−protein interaction revealed important drug targets, such as σ28 transcription factor, aminoacyl-tRNA synthetase, and diacylglycerol kinase, with significant (p < 0.05) enrichment. This study suggests that fish-isolate Aeromonas strains represent potential threat to aquaculture with subsequent risk of transferring antibiotic resistance to human pathogens.

Legacies of domestication, Neolithic diffusion and trade between Indian subcontinent and Island Southeast Asia shape maternal genetic diversity of Andaman cattle.

Andaman cattle is a precious indigenous livestock species endemic to Andaman and Nicobar Islands, India. Till date, origin and genetic makeup of the breed which is warranted for breed conservation is not known. Moreover, the spread of zebu cattle from Indus valley to different parts of Island Southeast Asia (ISEA) is not properly understood. Here, we report the genetic diversity, population structure of Andaman cattle and their evolution in the context of epicentre of zebu domestication and ISEA. High genetic diversity in complete mitochondrial D-loop sequences indicated the ability of the breed to withstand impending climate change. Total 81 haplotypes were detected and all of them except three belonged to Bos indicus. The presence of taurine haplotypes in Andaman cattle indicate introgression by European-derived cattle. A poor phylogenetic signal of Andaman cattle with genetic affinities with cattle of Indian subcontinent and ISEA was observed. The poor phylogenetic structure may be due to multidirectional gene flow from Indian subcontinent and ISEA, with which Andaman shares a close cultural and trade relationship from Neolithic age. We hypothesize that Andaman cattle is the outcome of Neolithic diffusion from centre of zebu domestication along with multidirectional commercial exchange between Indian subcontinent and ISEA.

Pharmacokinetics, bioavailability and withdrawal period of antibiotic oxytetracycline in catfish Pangasianodon hypophthalmus.

The antibiotic oxytetracycline (OTC) has been widely used for therapeutic and preventive management of bacterial diseases in finfish and shellfish. In the present study the bioavailability, pharmacokinetics, and withdrawal period of the OTC have been determined following in-feed administration in intensively cultured catfish Pangasianodon hypophthalmus. Furthermore, the pharmacokinetic parameters of oral route were also compared with parenteral route. Drug concentrations were measured in various tissues at different time intervals by LC-MS/MS. The study revealed the drug kinetics best followed the enterohepatic circulation model with very poor bioavailability and low blood concentration after oral administration. In the withdrawal study, after 10-days of in-feed administration at the therapeutic dose the drug reached very high concentrations in the liver and kidneys but did not attain minimum inhibitory concentrations (MICs) in blood or flesh. OTC concentration also did not exceed the recommended MRL value in flesh; however, considering high amounts of the chemical in the liver and kidneys a withdrawal period of 4 days (at 28 ± 1.5 oC) is recommended for consumer safety. Poor bioavailability and non-attainment of minimum therapeutic concentration in blood and flesh do not warrant in-feed administration of OTC for control of bacterial diseases in P. hypophthalmus. AVAILABILITY OF DATA AND MATERIALS: All data generated and analyzed during this study are included in this article. Raw data may be shared upon reasonable request.

Tri-Model Therapy: Combining Macrocyclic Lactone, Piperazine Derivative and Herbal Preparation in Treating Humpsore in Cattle.

Stephanofilariasis or humpsore is a chronic parasitic dermatitis of cattle. Various treatment regimens were attempted in the past but were found to be partially effective. Here, we claim a successful treatment regime using an FDA-approved macrocyclic lactone, a piperazine derivative, and an herbal preparation. Twenty-four cattle (18 affected and 6 unaffected) were selected and divided into Gr 1: positive control (infected without treatment; n = 6), Gr 2: treatment group (infected with treatment with ivermectin; n = 6), Gr 3: treatment group (infected with treatment with tri-model therapy including ivermectin, diethylcarbamazine citrate, and an herbal ointment, n = 6), and Gr 4: negative control (non-infected animals; n = 6). In Gr 2 and Gr 3, treatment to the ailing animals were given for 30 days. Lesion was significantly reduced in day 15 of post-treatment and completely healed on day 30 of post-treatment in Gr 3. Tri-model therapy recorded significant improvement in the surface area of the sore as compared to ivermectin administration alone. Antioxidants were increased and malondialdehyde (MDA) and cortisol concentrations were decreased significantly (p < 0.05) in Gr 3 than in untreated control group at day 14, 21 and 28. Histopathological changes in infected animals were characterized by parakeratotic hyperkeratosis along with presence of nucleated keratinocytes. There were infiltrations of polymorphonuclear cells specially eosinophils along with a few monomorphonuclear cells. Microfilarial organism was observed beneath the epidermis, which was surrounded by fibrocytes and infiltrated cells. In the tri-model-treated animal after recovery, the skin revived a normal architecture. Therefore, tri-model therapy has the potential to cure humpsore.

Host-Parasite Interaction in Sarcoptes scabiei Infestation in Porcine Model with a Preliminary Note on Its Genetic Lineage from India.

The burrowing mite Sarcoptes scabiei causes scabies in humans or mange in animals. It infests a wide range of mammalian species including livestock, companion animals, wild animals, and humans. Differential diagnosis of Sarcoptes varieties is key for epidemiological studies and for formulation of an eradication program. Host-parasite interaction at the systemic level is very important to understand the pathogenicity of the mite. This communication deals with the preliminary report on the genetic characterization of S. scabiei from India. Moreover, the effect of S. scabiei infestation on host physiology with special emphasis on serum biochemical parameters, lipid profile, oxidant/antioxidant balance, stress parameters, and immune responses were evaluated in a porcine model. Cytochrome C oxidase 1 and voltage-sensitive sodium channel based phylogenetic study could distinguish human and animals isolates but could not distinguish host or geographical specific isolates belonging to animal origin. An absence of host-specific cluster among animal isolates argues against the hypothesis of delineating S. scabiei as per host origin. Elevated levels of markers of liver function such as albumin, AST, ALT, ALP, and LDH in infested animals indicated impaired liver function in infested animals. S. scabiei infestation induced atherogenic dyslipidemia indicated by elevated levels of total cholesterol, low-density lipoprotein cholesterol and triglycerides, and a decreased level of high-density lipoprotein cholesterol. Oxidative stress in infested animals was indicated by a high level of nitric oxide and serum MDA as oxidative stress markers and low antioxidant capacity. S. scabiei triggered stress response and elevated levels of serum cortisol and heat shock proteins were recorded in infested animals. S. scabiei infestation increased the serum concentration of immunoglobulins and was associated with up-regulation of IL-2, IFN-γ, IL-1ß, and IL-4 indicating both Th1 and Th2 response. The results of the study will be helpful for a better understanding of host-parasite interaction at the systemic level in crusted scabies in pigs.

A Natural Quinazoline Derivative from Marine Sponge Hyrtios erectus Induces Apoptosis of Breast Cancer Cells via ROS Production and Intrinsic or Extrinsic Apoptosis Pathways.

Here, we report the therapeutic potential of a natural quinazoline derivative (2-chloro-6-phenyl-8H-quinazolino[4,3-b]quinazolin-8-one) isolated from marine sponge Hyrtios erectus against human breast cancer. The cytotoxicity of the compound was investigated on a human breast carcinoma cell line (MCF-7). Antiproliferative activity of the compound was estimated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. MTT assay showed significant inhibition of MCF-7 cells viability with the IC50 value of 13.04 ± 1.03 µg/mL after 48 h. The compound induced down-regulation of anti-apoptotic Bcl-2 protein and increase in the pro-apoptotic Bax/Bcl-2 ratio in MCF-7 cells. The compound activated the expression of Caspases-9 and stimulated downstream signal transducer Caspase-7. In addition, Caspase-8 showed remarkable up-regulation in MCF-7 cells treated with the compound. Moreover, the compound was found to promote oxidative stress in MCF-7 cells that led to cell death. In conclusion, the compound could induce apoptosis of breast carcinoma cells via a mechanism that involves ROS production and either extrinsic or intrinsic apoptosis pathways. The systemic toxic potential of the compound was evaluated in an in vivo mouse model, and it was found non-toxic to the major organs.

Understanding spatial and temporal patterns of fish diversity and assemblage structure vis-a-vis environmental parameters in a tropical Indian reservoir.

Reservoirs have been given priority as an important resource for fisheries enhancement in inland open waters. This paper described the spatial and temporal pattern of fish diversity using GIS platform, assemblage structure, and studied the influence of environmental parameters in these variables in a large tropical reservoir, Chandil, located in the eastern India using multiple approaches. Altogether, 42 fish species belonging to 30 genera were recorded from the reservoir, including two exotic species: pangas, Pangasianodon hypophthalmus, and Nile tilapia, Oreochromis niloticus. The diversity indices indicated lowest fish diversity in the lacustrine zone, but without distinct seasonal variation. The taxonomic distinctness was lower in the lacustrine zone as compared to other zones, and the summer season exhibited higher taxonomic distinctness, though the number of species was lowest. Most of the physicochemical parameters recorded are within the favorable range for fisheries enhancement. Among the environmental parameters, pH and nitrate significantly influenced the fish abundance. The study recommends suitable measures and interventions for conservation of the native fish diversity and sustainable fisheries development: closed season, protected/conservation area, introduction of fish aggregating device (FAD), and regulated fish culture in enclosures.

Inhibition of Oxidative Stress and Enhancement of Cellular Activity by Mushroom Lectins in Arsenic Induced Carcinogenesis.

Chronic arsenicosis is a major environmental health hazard throughout the world, including India. Animals and human beings are affected due to drinking of arsenic contaminated ground water, due to natural mineral deposits, arsenical pesticides or improperly disposed arsenical chemicals. Arsenic causes cancer with production of free radicals and reactive oxygen species (ROS) that are neutralized by an elaborate antioxidant defense system consisting of enzymes and numerous non-enzymatic antioxidants. Dietary antioxidant supplements are useful to counteract the carcinogenesis effects of arsenic. Oyster mushroom lectins can be regarded as ingredients of popular foods with biopharmaceutical properties. A variety of compounds have been isolated from mushrooms, which include polysaccharides and polysaccharopeptides with immune-enhancing effects. Lectins are beneficial in reducing arsenic toxicity due to anticarcinogenetic roles and may have therapeutic application in people suffering from chronic exposure to arsenic from natural sources, a global problem that is especially relevant to millions of people on the Indian subcontinent.

Characterization of arsenic-induced cytotoxicity in liver with stress in erythrocytes and its reversibility with Pleurotus florida lectin.

Arsenic is one of the most hazardous substances in the environment known to cause toxicity in multiple organs. Cell adhesion, morphological alterations, cell proliferation, terminal deoxyuridine triphosphate nick-end labeling (TUNEL) and caspase-3/CPP32 fluorometric protease assay were important biomarkers to assess apoptosis in cells. This study aimed to evaluate arsenic-induced apoptosis in the hepatocytes of rat and its protective efficacy with coadministration of ascorbic acid (AA) and Pleurotus florida lectin (PFL) individually. Results of the present study also showed that arsenic caused cytotoxicity by elevating morphological alterations, TUNEL-positive nuclei, caspase-3 activity and DNA damage and reducing cell adhesion and cell proliferation in a time-dependent manner. The apoptosis in hepatocytes was reverted to normal value after coadministration of mushroom lectin in arsenic-exposed rat. The study provided significant evidence that PFL has antiapoptotic property against arsenic-induced toxicity. The beneficial effect of PFL was proportional to its duration of exposure. Retard activities of superoxide dismutase and catalase, enhanced lipid peroxidation as well as protein carbonyl in erythrocytes caused by arsenic could also be maintained toward normalcy by supplementation of AA and PFL. These antioxidative effects were exhibited in a time-dependant manner. In rat, treatment with AA and PFL prevented alteration of plasma enzyme activities caused by arsenic. The results concluded that treatment with PFL has significant role in protecting animals from arsenic-induced erythrocytic damage. This finding might be of therapeutic benefit in people suffering from chronic exposure to arsenic from natural sources, a global problem especially relevant to millions of people on the Indian subcontinent.

Subclinical arsenicosis in cattle in arsenic endemic area of West Bengal, India.

Arsenic is ubiquitously found metalloid that commonly contaminates drinking water and agricultural food. To minimise the ecotoxicological effect of arsenic in the environment, it is important to ameliorate the deleterious effects on human and animal health. We investigated the effects of arsenic on cattle by estimating arsenic concentration in biological samples of cattle that consumed contaminated drinking water and feedstuffs directly or indirectly. We have selected arsenic prone village that is Ghentugachi, Nadia district, West Bengal, India, along with arsenic safe control village, Akna in Hoogli district, West Bengal, India. It is found that arsenic is deposited highly in blood, urine and faeces. Agricultural field is contaminated through cattle urine, hair, faeces, cow dung cakes and farmyard manure. Bioconcentration factor and biotransfer factor are two important biomarkers to assess the subclinical toxicity in cattle, as they do not exhibit clinical manifestation like human beings.

Effect of Pleurotus florida lectin (PFL) on arsenic-induced activities of splenocytes in rat.

The present study was undertaken to investigate the protective effect of Pleurotus florida lectin (PFL) against arsenic-induced cytotoxicity and oxidative damages in freshly isolated splenocytes of rodents. Our finding indicated that arsenic caused reduction in cell adhesion, morphological alterations, cell proliferation, nitro blue tetrazolium (NBT) index, superoxide dismutase (SOD) activity, catalase (CAT) activity and relative mRNA expression of SOD2 in relation to housekeeping gene glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and increased production of nitric oxide (NO), protein carbonyl (PC) and lipid peroxidation levels (LPO) assembled to play key factors for cytotoxicity and oxidative stress. PFL normalized cellular damages and enhanced SOD production pathway relating to gene expression. Further studies are needed to address effective phytochemicals of the edible mushroom and their mechanism.

Arsenic residue in the products and by-products of chicken and ducks: a possible concern of avian health and environmental hazard to the population in West Bengal, India.

Arsenicosis caused due to drinking of arsenic contaminated ground water is a major environmental health hazard throughout the world. We evaluated the ecotoxicological effect of arsenic on chicken and duck in an arsenic endemic zone. The concentration of arsenic was higher in chicken and duck feed and their by-products than that in the respective samples of control area. Arsenic concentration in the eggs of both chicken and duck was higher than that in the respective samples of control area. Thus, we concluded that arsenic enters into food chain through the intake of contaminated eggs. Furthermore, adverse health effect of arsenic on avian population is due to the alteration in haematobiochemical indices.

Evidence of antiapoptotic properties of Pleurotus florida lectin against chronic arsenic toxicity in renal cells of rats.

Chronic arsenic exposure results in toxicity in humans and causes many toxicologic manifestations. Apoptosis was measured by cell adhesion, morphologic alterations, cell proliferation, terminal deoxyuridine triphosphate nick-end labeling (TUNEL), and caspase-3/CPP32 fluorometric protease assay. Results of the present study suggested that arsenic administration in rats caused apoptosis by elevating morphologic alterations, TUNEL-positive nuclei, caspase-3 activity, and DNA damage and by reducing cell adhesion and cell proliferation in a time-dependent manner. The apoptosis in renal cells of arsenic-exposed rats reverted to normal values after coadministration of mushroom lectin. This study provided significant evidence that Pleurotus florida lectin has an antiapoptotic property by protecting from arsenic-induced toxicity. The beneficial effect of Pleurotus florida lectin was proportional to its duration of exposure. This finding might be of therapeutic benefit in people suffering from chronic exposure to arsenic from natural sources, a global problem that is especially relevant to millions of people on the Indian subcontinent.

Metabolic adaptations to arsenic-induced oxidative stress in male wistar rats.

The present study was planned to investigate the effect of arsenic in rats on several biochemical indices of oxidative stress. Rats were exposed to arsenite in drinking water for upto 12 weeks. Chronic exposure to arsenic for a period of 12 weeks significantly (p < 0.05) increased arsenic burden in blood, liver, and kidney. Several intrinsic antioxidant defenses were activated after a 4-week exposure to arsenic. Some remained elevated, but others became depressed over a longer exposure period. Alterations in most of the biochemical variables reached statistical significant (p < 0.05). Arsenic significantly (p < 0.01) reduced mRNA expression of the superoxide dismutase 2 (SOD2) gene with respect to the glyceraldehyde 3-phosphate dehydrogenase (GAPDH) gene. These observations indicated that prolong exposure to arsenic causes induction of oxidative stress and biochemical alterations.

Chronic arsenicosis in goats with special reference to its exposure, excretion and deposition in an arsenic contaminated zone.

Thirty goats were selected randomly from a village of Nadia district, West Bengal according to the previous reports of human being suffering from chronic arsenicosis. Environmental samples viz. drinking water, rice plants and grass used for goat and biological samples viz. blood, urine, faeces, hair and meat were collected to evaluate the arsenic status. It was found that arsenic concentration in both environmental and biological samples was significantly (p<0.01) higher rather than respective samples on control zone. Bio-concentration factor (BCF) and bio-transfer factor (BTF) are indicated to evaluate the subclinical toxicity in goat as they do not exhibit clinical manifestation like human beings.