Sumanta De

Effect of ascorbic acid on blood oxidative stress in experimental chronic arsenicosis in rodents.

Ascorbic acid is a sugar acid and an essential vital food nutrient found mainly in fruits and vegetables. The purpose of this study was to investigate the effects of ascorbic acid against arsenic induced oxidative stress in blood of rat. In rat, treatment with ascorbic acid prevented the increased serum enzymatic activity of AST, ALT, ALP, ACP and LDH. In addition, treatment with ascorbic acid prevented elevated production of LPO, PC and NO and restored the depletion of reduced SOD and CAT activities. Interestingly, ascorbic acid markedly upregulated lymphocytes relative mRNA expression of lymphocytes SOD2 gene corresponding to GAPDH, house keeping candidate gene in arsenic-treated rat, which might provide anti-oxidative activity in the blood.

L-Ascorbate protects rat hepatocytes against sodium arsenite—induced cytotoxicity and oxidative damage:

Sodium arsenite—exposed hepatocytes of rat showed higher production of nitric oxide (NO) and increased lipid peroxidation (LPO) level vis-a-vis activity of superoxide dismutase (SOD) and catalase (CAT) were significantly lowered. Subsequently, the cell proliferation index (CPI) and cell viability were also reduced. Treatment with L-ascorbate was found effective in normalizing the arsenic-induced alteration of SOD and CAT activity and LPO level in rat hepatocytes. These observations indicated that L-ascorbate also has potent cytoprotective role as it could reduce the NO production and normalize the cell proliferation and viability of hepatocytes. Therefore, the in vitro study suggested that ascorbic acid is helpful to ameliorate the arsenic-induced cytotoxicity and oxidative stress of rat hepatocytes.

Ground water arsenic contamination in West Bengal, India: a risk of sub-clinical toxicity in cattle as evident by correlation between arsenic exposure, excretion and deposition.

Arsenic contamination of ground water in West Bengal, India, is a great concern for both human and livestock populations. Our study investigated and correlated the arsenic concentration in the drinking water, urinary excretion and deposition of total arsenic in hair of cattle at an arsenic contaminated zone in West Bengal. The results of our study indicated that the average concentration of arsenic in tube well water in contaminated villages ranged from 0.042 to 0.251 ppm and a statistical significant (p < 0.01) difference was seen when compared to samples from a non-contaminated zone. The arsenic concentration in urine and hair of cattle ranged between 0.245—0.691 ppm and 0.461—0.984 ppm, respectively. A close relationship was found between the total arsenic in drinking water urinary excretion (r2 = 0.03664, p < 0.05) and the arsenic concentration in hair (r2 = 0.03668, p < 0.05). Our findings indicate that quantification of arsenic concentration in cattle urine and hair can serve as biomarkers for both present and past exposure in cattle population.

Supplementation of ascorbic acid prevents oxidative damages in arsenic-loaded hepatic tissue of rat: An ex vivo study

Oxidative stress due to arsenic toxicity and ameliorative potentiality of L-ascorbic acid was evaluated in an ex vivo system of rat hepatic tissue. The study revealed that arsenic increased the activity of superoxide dismutase (SOD) and catalase (CAT) and the level of lipid peroxidation (LPO), protein carbonyl (PC) and nitric oxide (NO) at 1 hour, 1.5 hours and 2 hours of incubation. Co-treatment with L-ascorbic acid was found effective to normalize the activity of SOD and CAT and the production of LPO, PC and NO in hepatic tissue. This ex vivo study suggested that ascorbic acid is helpful to ameliorate arsenic-induced oxidative stress. This may be one of the alternative screening systems to study the efficacy of antioxidant and hepatoprotective agent.

Molecular and biochemical mining of heat-shock and 14-3-3 proteins in drug-induced protoscolices of Echinococcus granulosus and the detection of a candidate gene for anthelmintic resistance

Cystic echinococcosis (CE) caused by the larval stage of Echinococcus granulosus is a disease that affects both humans and animals. In humans the disease is treated by surgery with a supplementary option of chemotherapy with a benzimidazole compound. During the present study heat-shock protein 60 (HSP 60) was identified as one of the most frequently expressed biomolecules by E. granulosus after albendazole treatment. Data were correlated with 14-3-3 protein signature, and overexpression of this molecule after albendazole induction was an indicator of cell survival and signal transduction during in vitro maintenance of E. granulosus for up to 72 h. This observation was further correlated with a uniform expression pattern of a housekeeping gene (actin II). Out of three β-tubulin gene isoforms of E. granulosus, β-tubulin gene isoform 2 showed a conserved point mutation indicative of benzimidazole resistance.

Mushroom lectin protects arsenic induced apoptosis in hepatocytes of rodents

Acute and chronic arsenic exposure result in toxicity both in human and animal beings and cause many hepatic and renal manifestations. The present study stated that mushroom lectin prevents arsenic-induced apoptosis. Apoptosis was measured by morphological alterations, cell proliferation index (CPI), phagocytic activity (nitro blue tetrazolium index; NBT), nitric oxide (NO) production, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, DNA fragmentation and caspase-3 activity. Arsenic exposure at 5 μM in the form of sodium arsenite resulted in significant elevation of deformed cells, NO production, TUNEL stained nuclei of hepatocytes, DNA fragmentation and caspase-3 activity. But the CPI and NBT index were significantly declined in arsenic-treated hepatocytes. The beneficial effect of mushroom lectin at 10 μg/mL, 20 μg/mL and 50 μg/mL) showed increased CPI and phagocytic activity. Mushroom lectin at those concentrations reduced deformed cells, NO production, DNA fragmentation and caspase-3 activity of hepatocytes. But significant better protection was observed in 50 μg/mL mushroom lectin-treated hepatocytes. This finding may be of therapeutic benefit in people suffering from chronic arsenic exposure.

Relative expression of antigen B coding gene of bubaline isolates of Echinococcus granulosus in fertile and sterile cysts

This article communicates the relative quantification of five isoforms of antigen B (AgB) of Echinococcus granulosus. Relative expression of the AgB was quantified in active and inactive cysts. Cysts with germinal membrane, clear cyst fluid and protoscoleces showed uniform expression of the five isoforms and were utilized as control. Relative expression of AgB1 was the highest in cysts, where calcification has initiated. AgB2 and AgB4 were expressed more in fertile cysts irrespective of the condition of germinal membrane. The lowest expression of AgB3 was seen in calcified cysts. The relative expression of AgB5 could not be correlated with respect to the condition of the cyst because AgB5 is typically expressed by the adult stage of the parasite.

Molecular differentiation of cryptic stage of Echinococcus granulosus and Taenia species from faecal and environmental samples

Objective To differentiate cryptic stage of Echinococcus granulosus (E. granulosus) and Taenia by PCR-RFLP and sequence information of amplicon. Methods DNA were isolated from metacestodes stage of Taenia and E. granulosus using DNA isolation kit (Q-BIOgene kit, USA), the amplified and purified DNA product was then cloned and sent for sequencing. The generating sequence information was used for amplicons identification. Results Out of 112 faecal and environmental samples, 16 exhibited positive result. The product size of amplicon positive for E. granulosus was 310 bp; whereas, for Taenia spp. sizes varied from 379 to 388 bp. Restriction profile of actin II with Csp61 also differed Taenia spp. and E. granulosus . Conclusions The result of the study indicated that, the primers were useful to differentiate cryptic stage of the two genera which is yet to be reported earlier.

Relative expression of the 14-3-3 gene in different morphotypes of cysts of Echinococcus granulosus isolated from the Indian buffalo.

The metacestode stage of Echinococcus granulosus is of zoonotic importance. In general, the 14-3-3 protein is involved in multiplication and survival of eukaryotes. Therefore, this communication presents succinct information on relative expression of the 14-3-3 protein in six different morphotypes of cysts of E. granulosus. All isolated E. granulosus belonged to the common sheep strain (G1). Relative expression of the 14-3-3 protein was higher in fertile cysts when compared to sterile cysts. The predicted amino acid sequence of the 14-3-3 protein was closely clustered with zeta-type isoforms 1 and 2 of the 14-3-3 protein. In addition, the present study demonstrates the presence of the 14-3-3 protein which until now had not been detected in the germinal layer. Our findings indicate that the expression of this biomolecule in the germinal layer of sterile organisms may contribute to the development and survival of the parasite in the host. The uniform expression of actin II conclusively proves the survivability of the harvested organisms.

Intra-species sequence variability in 28s rRNA gene of Oesophagostomum venulosum isolated from goats of West Bengal, India

Objective: To identify genotypes of Oesophagostmum venulosum (O. venulosum) prevailing in West Bengal, India by comparing variation of nucleotide sequences among 28S rRNA. Methods: PCR amplification of partial segment of 28S rRNA sequence and analysis of sequence amplified product by single strand conformation polymorphism (SSCP). Results: Two distinct conformers among male and female parasites were identified by PCR-SSCP analysis. Sequence analysis among conformers revealed the presence of five single nucleotide polymorphisms (SNP) in codon 64, 66, 86, 125 and 146. Secondary RNA prediction structure showed that out of 5 SNPs, 4 occurred at interior loop of RNA which confirmed evolutionary changes among isolates prevailing in this region. Conclusions: SNPs occured in different isolates of O. venulosum might influence critical changes in rRNA folding pattern which influence evolutionary changes among isolates.