Melatonin as an Ameliorative Agent Against Cadmium- and Lead-Induced Toxicity in Fish: an Overview.

Diverse anthropogenic activities and lack of knowledge on its consequences have promoted serious heavy metal contaminations in different aquatic systems throughout the globe. The non-biodegradable nature of most of these toxic heavy metals has increased the concern on their possible bioaccumulation in aquatic organisms as well as in other vertebrates. Among these aquatic species, fish are most sensitive to such contaminated water that not only decreases their chance of survivability in the nature but also increases the probability of biomagnifications of these heavy metals in higher order food chain. After entering the fish body, heavy metals induce detrimental changes in different vital organs by impairing multiple physiological and biochemical pathways that are essential for the species. Such alterations may include tissue damage, induction of oxidative stress, immune-suppression, endocrine disorders, uncontrolled cell proliferation, DNA damage, and even apoptosis. Although uncountable reports have explored the toxic effects of different heavy metals in diverse fish species, but surprisingly, only a few attempts have been made to ameliorate such toxic effects. Since, oxidative stress seems to be the underlying common factor in such heavy metal-induced toxicity, therefore, a potent and endogenous antioxidant with no side effect may be an appropriate therapeutic solution. Apart from summarizing the toxic effects of two important toxicants, i.e., cadmium and lead in fish, the novelty of the present treatise lies in its arguments in favor of using melatonin, an endogenous free radical scavenger and indirect antioxidant, in ameliorating the toxic effects of heavy metals in any fish species.

An update of the species of Myxosporea (Cnidaria, Myxozoa) described from Indian fish.

A synopsis of Myxosporea (Cnidaria, Myxozoa) species described in about the last 14 years in Indian fish is provided. The synopsis include a total of 97 new species, and 18 species redescribed including significant new data, namely molecular characterization, distributed by 19 genera. For each species are indicated, in tabulated format, the morphological characteristics and the Gen Bank Accession Number whenever possible. Data about the type host and type locality are included also, and a complete list of references is provided. The information presented, combined with former synopsis, allow an update general view about these parasites infecting Indian fish hosts.

Improved drug carriage and protective potential against Cisplatin-induced toxicity using Boldine-loaded PLGA nanoparticles.

BACKGROUND: Cisplatin is a widely-used potent anti-cancer drug having severe side-effects precluding its sustained use. OBJECTIVES: Poly (lactide-co-glycolide) (PLGA)-nanoparticles loaded Boldine, an antioxidant ingredient of ethanolic extract of Boldo plant (Peumus boldus) was tested in cancer mice model, Mus musculus to examine if it could reduce unwanted Cisplatin-induced toxicity in normal tissue. MATERIAL AND METHODS: Nano-encapsulation of Boldine was done by following the standardized solvent displacement method. Physico-chemical characterization of PLGA-encapsulated nano-Boldine (NBol) was accomplished through analyses of various spectroscopic techniques. Status of major antioxidant enzymes, functional markers, and lipid peroxidation (LPO) was also determined in certain tissue and serum samples. Percentage of cells undergoing cytotoxic death, Reactive oxygen species (ROS) accumulation and mitochondrial functioning were analyzed in both normal and cancer mice. Nanoscale changes in chromatin organization were assessed by Transmission electron microscopy (TEM). mRNA and protein expressions of Top II, Bax, Bcl-2, Cyt c, caspase 3 were studied by RT-PCR, immunoblot and immunofluorescence. RESULTS: NBol had faster mobility, site-specific action and ability of sustained particle release. NBol readily entered cells, prevented Cisplatin to intercalate with dsDNA resulting in reduction of chromatin condensation, with corresponding changes in ROS levels, mitochondrial functioning and antioxidant enzyme activities, leading to reduction in Deoxyribose nucleic acid (DNA) damage and cytotoxic cell death. Expression pattern of apoptotic genes like Top II, p53, Bax, Bcl-2, cytochrome c and caspase-3 suggested greater cytoprotective potentials of NBol in normal tissues. CONCLUSIONS: Compared to Boldine (Bol), NBol had better ability of drug carriage and protective potentials (29.00% approximately) against Cisplatin-induced toxicity. Combinational therapeutic use of PLGA-NBol can reduce unwanted Cisplatin-induced cellular toxicity facilitating use of Cisplatin.

Isolation, characterization and growth kinetics of phenol hyper-tolerant bacteria from sewage-fed aquaculture system.

Pollution of aquatic resources is increasing day-by-day, and phenolic compounds are common pollutants negatively impacting aquatic biodiversity and production. This study aimed at isolation of phenol hyper-tolerant bacteria from polluted aquaculture resource so that they might be useful in aquaculture systems. Four phenol hyper-tolerant bacterial strains were isolated from sewage fed East Kolkata Wetlands, a Ramsar site. By 16S rDNA sequence, cell morphology and biochemical characteristics the strains PDB2, PDB13, PDB16, and PDB26 were identified as Acinetobacter sp., Acinetobacter junii, Pseudomonas citronellolis, and Bacillus cereus, respectively. Pseudomonas citronellolis strain PDB16, described in this study, is possibly the first report of phenol hyper-tolerant strain in this species. All the four strains degraded 600 mg L-1 phenol within 5 days and expressed catechol 1,2-dioxygenase but lacked catechol 2,3-dioxygenase enzyme suggesting that the bacteria used the ortho-cleavage pathway for phenol degradation. In growth kinetic study Edwards and Aiba model, rather than the most popular Haldane model, gave the best fit indicating behavioral divergence of these strains with those from petroleum contaminated environments. The phenol degrading bacteria isolated from a polluted sewage fed aquaculture system might be useful in degradation and remediation of polluted aquaculture resources as well as inland open waters.

Mitigating peroxynitrite mediated mitochondrial dysfunction in aged rat brain by mitochondria-targeted antioxidant MitoQ.

Although reactive oxygen species mediated oxidative stress is a well-documented mechanism of aging, recent evidences indicate involvement of nitrosative stress in the same. As mitochondrial dysfunction is considered as one of the primary features of aging, the present study was designed to understand the involvement of nitrosative stress by studying the impact of a mitochondria-targeted antioxidant MitoQ, a peroxynitrite (ONOO-) scavenger, on mitochondrial functions. Four groups of rats were included in this study: Group I: Young-6 months (-MitoQ), Group II: Aged-22 months (- MitoQ), Group III: Young-6 months (+ MitoQ), Group IV: Aged-22 months (+ MitoQ). The rats belonging to group III and IV were treated with oral administration of MitoQ (500 µM) daily through drinking water for 5 weeks. MitoQ efficiently suppressed synaptosomal lipid peroxidation and protein oxidation accompanied by diminution of nitrite production and protein bound 3-nitrotyrosine. MitoQ normalized enhanced caspase 3 and 9 activities in aged rat brains and efficiently reversed ONOO- mediated mitochondrial complex I and IV inhibition, restored mitochondrial ATP production and lowered mitochondrial membrane potential loss. To ascertain these findings, a mitochondrial in vitro model (iron/ascorbate) was used involving different free radical scavengers and anti-oxidants. MitoQ provided better protection compared to mercaptoethylguanidine, N-nitro-L-arginine-methyl ester and superoxide dismutase establishing the predominancy of ONOO- in the process compared to •NO and O 2•- . These results clearly highlight the involvement of nitrosative stress in aging process with MitoQ having therapeutic potential to fight against ONOO- mediated aging deficits.

Effects of bisphenol A (BPA) on brain-specific expression of cyp19a1b gene in swim-up fry of Labeo rohita.

Estrogen regulates numerous developmental and physiological processes and effects are mediated mainly by estrogenic receptors (ERs), which function as ligand-regulated transcription factor. ERs can be activated by many different types endocrine disrupting chemicals (EDCs) and interfere with behaviour and reproductive potential of living organism. Estrogenic regulation of membrane associated G protein-coupled estrogen receptor, GPER activity has also been reported. Bisphenol A (BPA), a ubiquitous endocrine disruptor is present in many household products, has been linked to many adverse effect on sexual development and reproductive potential of wild life species. The present work is aimed to elucidate how an environmentally pervasive chemical BPA affects in vivo expression of a known estrogen target gene, cyp19a1b in the brain, and a known estrogenic biomarker, vitellogenin (Vg) in the whole body homogenate of 30 days post fertilization (dpf) swim-up fry of Labeo rohita. We confirm that, like estrogen, the xenoestrogen BPA exposure for 5-15 days induces strong overexpression of cyp19a1b, but not cyp19a1a mRNA in the brain and increase concentration of vitellogenin in swim-up fry. BPA also induces strong overexpression of aromatase B protein and aromatase activity in brain. Experiments using selective modulators of classical ERs and GPER argue that this induction is largely through nuclear ERs, not through GPER. Thus, BPA has the potential to elevate the levels of aromatase and thereby, levels of endogenous estrogen in developing brain. These results indicate that L. rohita swim-up fry can be used to detect environmental endocrine disruptors either using cyp19a1b gene expression or vitellogenin induction.

Estrogen-regulated expression of cyp19a1a and cyp19a1b genes in swim-up fry of Labeo rohita.

P450 aromatase is the terminal enzyme in the steroidogenic pathway and catalyzes the conversion of androgens to estrogens. The expression of cyp19a1 genes in brain and gonad of Indian major carp, Labeo rohita swim-up fry was measured by quantitative real-time polymerase chain-reaction. Results demonstrated that cyp19a1b and cyp19a1a predominate in brain and gonad respectively. Treatment of fry with an aromatase inhibitor fadrozole for 6days attenuated brain cyp19a1b expression, but not cyp19a1a of gonad. Fadrozole also attenuated brain aromatase activity. Treatment with 17ß-estradiol (E2) for 6days resulted in up-regulation of brain cyp19a1b transcripts in a dose- and time-dependent manner, but not cyp19a1a. Whole-body concentration of vitellogenin also increased in response to E2. Altogether, these results indicate L. rohita swim-up fry can be used to detect environmental estrogens either using vitellogenin induction or cyp19a1b gene expression.

Anticancer potential of Conium maculatum extract against cancer cells in vitro: Drug-DNA interaction and its ability to induce apoptosis through ROS generation.

OBJECTIVE: Conium maculatum extract is used as a traditional medicine for cervix carcinoma including homeopathy. However, no systematic work has so far been carried out to test its anti-cancer potential against cervix cancer cells in vitro. Thus, in this study, we investigated whether ethanolic extract of conium is capable of inducing cytotoxicity in different normal and cancer cell lines including an elaborate study in HeLa cells. MATERIALS AND METHODS: Conium's effects on cell cycle, reactive oxygen species (ROS) accumulation, mitochondrial membrane potential (MMP) and apoptosis, if any, were analyzed through flow cytometry. Whether Conium could damage DNA and induce morphological changes were also determined microscopically. Expression of different proteins related to cell death and survival was critically studied by western blotting and ELISA methods. If Conium could interact directly with DNA was also determined by circular dichroism (CD) spectroscopy. RESULTS: Conium treatment reduced cell viability and colony formation at 48 h and inhibited cell proliferation, arresting cell cycle at sub-G stage. Conium treatment lead to increased generation of reactive oxygen species (ROS) at 24 h, increase in MMP depolarization, morphological changes and DNA damage in HeLa cells along with externalization of phosphatidyl serine at 48 hours. While cytochrome c release and caspase-3 activation led HeLa cells toward apoptosis, down-regulation of Akt and NFkB inhibited cellular proliferation, indicating the signaling pathway to be mediated via the mitochondria-mediated caspase-3-dependent pathway. CD-spectroscopy revealed that Conium interacted with DNA molecule. CONCLUSION: Overall results validate anti-cancer potential of Conium and provide support for its use in traditional systems of medicine.

Low doses of ethanolic extract of Boldo (Peumus boldus) can ameliorate toxicity generated by cisplatin in normal liver cells of mice in vivo and in WRL-68 cells in vitro, but not in cancer cells in vivo or in vitro.

OBJECTIVE: Use of cisplatin, a conventional anticancer drug, is restricted because it generates strong hepatotoxicity by accumulating in liver. Therefore its anticancer potential can only be fully exploited if its own toxicity is considerably reduced. Towards this goal, ethanolic extract of the plant, Boldo (Peumus boldus), known for its antihepatotoxic effects, was used simultaneously with cisplatin, to test its ability to reduce cisplatin's cytotoxicity without affecting its anticancer potential. METHODS: The cytotoxicity of Boldo extract (BE) and cisplatin, administered alone and in combination, was determined in three cancer cell lines (A549, HeLa, and HepG2) and in normal liver cells (WRL-68). Drug-DNA interaction, DNA damage, cell cycle, apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP, ΔΨ) were also studied. Hepatotoxicity and antioxidant activity levels were determined by alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and glutathione assays in mice. The cytotoxicity of related proteins was tested by Western blotting. RESULTS: Co-administration of BE and cisplatin increased viability of normal cells, but had no effect on the viability of cancer cells. Boldo protected liver from damage and normalized different antioxidant enzyme levels in vivo and also reduced ROS and re-polarized MMP in vitro. Bax and cytochrome c translocation was reduced with caspase 3 down-regulation. Further, a drug-DNA interaction study revealed that BE reduced cisplatin's DNA-binding capacity, resulting in a reduction in DNA damage. CONCLUSION: Results indicated that a low dose of BE could be used beneficially in combination with cisplatin to reduce its toxicity without hampering cisplatin's anticancer effect. These findings signify a potential future use of BE in cancer therapy.

Low doses of ethanolic extract of Boldo (Peumus boldus) can ameliorate toxicity generated by cisplatin in normal liver cells of mice in vivo and in WRL-68 cells in vitro, but not in cancer cells in vivo or in vitro / 中西医结合学报

Use of cisplatin, a conventional anticancer drug, is restricted because it generates strong hepatotoxicity by accumulating in liver. Therefore its anticancer potential can only be fully exploited if its own toxicity is considerably reduced. Towards this goal, ethanolic extract of the plant, Boldo (Peumus boldus), known for its antihepatotoxic effects, was used simultaneously with cisplatin, to test its ability to reduce cisplatin's cytotoxicity without affecting its anticancer potential.