Naringenin suppresses aluminum-induced experimental hepato-nephrotoxicity in mice through modulation of oxidative stress and inflammation.

Aluminum is a widely used metal substance in daily life activities that has been shown to cause severe hepato-nephrotoxicity with long-term exposure. Natural dietary flavonoids are being utilized as a newer pharmaceutical approach against various acute and chronic diseases. Naringenin (NAR) has shown efficient therapeutic properties, including effects against metal toxicities. However, the protective efficacy of NAR on aluminum chloride (AlCl3)-induced hepato-renal toxicity needs investigation as aluminum has shown serious environmental toxicity and bioaccumulation behavior. In this study, mice were treated with AlCl3 (10 mg/kg b.w./day) to assess toxicities, and a group of mice were co-treated with NAR (10 mg/kg b.w./day) to assess the protective effects of NAR against hepato-nephrotoxicity. The levels of blood serum enzymes, oxidative stress biomarkers, inflammatory cytokines, and the apoptosis marker caspase-3 were measured using histological examinations. NAR treatment in AlCl3-treated mice resulted in maintained levels of liver and kidney function enzymes and lipid profiles. NAR treatment attenuated oxidative stress by regulating the levels of nitric oxide, advance oxidation of protein products, protein carbonylation, and lipid peroxidation. NAR also replenished reduced antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and reduced the levels of glutathione and oxidized glutathione. NAR regulated the levels of pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α) and elevated the levels of anti-inflammatory cytokines (IL-4, IL-10, and IFN-γ). The histological study further confirmed the protective effects of NAR against AlCl3-induced hepato-renal alterations. NAR decreased the expression of caspase-3 as a mechanism of protective effects against apoptotic damage in the liver and kidney of AlCl3-treated mice. In summary, this study demonstrated the antioxidant and anti-inflammatory properties of NAR, leading to the suppression of AlCl3-triggered hepato-renal apoptosis and histological alterations. The results suggest that aluminum toxicity needs to be monitored in daily life usage, and supplementation of the natural dietary flavonoid naringenin may help maintain liver and kidney health.

Assessment of Lactobacillus rhamnosus mediated protection against arsenic-induced toxicity in zebrafish: a qPCR-based analysis of Firmicutes and Bacteroidetes groups and embryonic development.

Arsenic poses a significant health risk worldwide, impacting the gut microbiota, reproductive health, and development. To address this issue, a cost-effective method like probiotic supplementation could be beneficial. However, the interplay between arsenic toxicity, probiotics, gut microbiota, and maternal transcript modulation remains unexplored. This study investigates the impact of Lactobacillus rhamnosus (L. rhamnosus) DSM 20021 on the proportions of Firmicutes and Bacteroidetes, as well as its effects on embryonic development in zebrafish induced by arsenic trioxide (As2O3). Adult zebrafish were exposed to both high and environmentally relevant concentrations of As2O3 (10, 50, and 500 ppb) for 1, 6, and 12 weeks. qPCR analysis revealed increased proportions of Firmicutes and Bacteroidetes in all As2O3-exposed and As2O3 + L. rhamnosus-exposed groups, while no significant changes were observed in groups exposed only to L. rhamnosus DSM 20021. The larvae, exposed to 500 ppb of As2O3 for 12 weeks, exhibited low growth, decreased survival rates, and morphological deformities. However, these adverse effects were reversed upon exposure to only L. rhamnosus DSM 20021. Furthermore, the expression of DVR1 and ABCC5, which are involved in defense against xenobiotics and embryo development, decreased significantly in As2O3 (500 ppb) and As2O3 (500 ppb) + L. rhamnosus-exposed groups, whereas ameliorative effects were observed in only L. rhamnosus DSM 20021-exposed groups.

Mechanism of action of certain medicinal plants for the treatment of asthma.

ETHNOPHARMACOLOGICAL RELEVANCE: Asthma is often treated and prevented using the pharmacological properties of traditional medicinal plants. These healthcare systems are among the most well-known, conveniently accessible, and economically priced in India and several other Asian countries. Traditional Indian Ayurvedic plants have the potential to be used as phyto-therapeutics, to create novel anti-asthmatic drugs, and as a cost-effective source of pharmaceuticals. Current conventional therapies have drawbacks, including serious side effects and expensive costs that interfere with treatment compliance and affect the patient's quality of life. The primary objective of the article is to comprehensively evaluate the advancement of research on the protective phytochemicals of traditional plants that target immune responses and signaling cascades in inflammatory experimental asthma models. The study would assist in paving the way for the creation of natural phytomedicines that are protective, anti-inflammatory, and immunomodulatory against asthma, which may then be used in individualized asthma therapy. AIM OF THE STUDY: The study demonstrates the mechanisms of action of phytochemicals present in traditional medicinal plants, diminish pulmonary disorder in both in vivo and in vitro models of asthma. MATERIALS AND METHODS: A comprehensive review of the literature on conventional plant-based asthma therapies was performed from 2006 to 2022. The study uses authoritative scientific sources such as PubMed, PubChem Compound, Wiley Online Library, Science Direct, Springer Link, and Google Scholar to collect information on potential phytochemicals and their mechanisms of action. World Flora Online (http://www.worldfloraonline.org) and Plants of the World Online (https://wcsp.science.kew.org) databases were used for the scientific names of medicinal plants. RESULTS: The study outlines the phytochemical mechanisms of some traditional Ayurveda botanicals used to treat asthma. Active phytochemicals including curcumin, withaferin-A, piperine, glabridin, glycyrrhizin, 18ß-glycyrrhetinic acid, trans-cinnamaldehyde, α-hederin, thymoquinone, eugenol, [6]-shogoal, and gingerol may treat asthma by controlling inflammation and airway remodeling. The study concluded that certain Ayurvedic plants' phytochemicals have the ability to reduce inflammation and modulate the immune system, that can effectively cure asthma. CONCLUSION: Plants used in traditional Ayurvedic medicine have been utilized for millennia, advocating phyto-therapy as a treatment for a variety of illnesses. A theoretical foundation for the use of cutting-edge asthma treatments has been built with the growth of experimental research on traditional phytochemicals. In-depth phytochemical research for the treatment of asthma using Indian Traditional Ayurvedic herbs is compiled in the study. The approach for preventative therapeutics and cutting-edge alternatives to battle the molecular pathways in the pathophysiology of asthma are the key themes of the study. The phytochemical mechanism of action of traditional Ayurvedic herbs is explained to get the attention of the pharmaceutical industry so they can make future anti-asthma drugs for personalized asthma care in the community. The study develops strategies for customized phyto-therapeutics, concentrating on low-cost, side-effect-free approaches that employ bioactive phytochemicals from plants as the major source of effective anti-asthmatic therapy.

Metagenomic Insights into the Gut Microbiota of Eudrilus eugeniae (Kinberg) and Its Potential Roles in Agroecosystem.

Gut microbiomes, a consortium of microorganisms that live in the animal gut, are highly engineered microbial communities. It makes a major contribution to digestive health, metabolism management, and the development of a strong immune system in the host. The present study was taken up to answer the long-running question about the existence of truly indigenous microflora of the epigeic earthworm gut. This is due to the general difficulties of culturing many of the microorganisms found in soil or earthworms' gut. Keeping this fact in a view, the metagenomics approach using 16S rRNA marker gene incorporated with amplicon-based sequencing was used to explore microbiota of commercially overriding, diversely fed epigeic earthworm Eudrilus eugeniae (Kinberg) in three varied habitats viz., artificial soil (AS), organic agricultural farm soil (OAFS) and conventional agriculture farm soil (CAFS). There are predominant bacteria that belong to different phyla such as Proteobacteria (29.72-76.81%), Actinobacteria (11.06-34.42%), Firmicutes (6.02-19.81%), and Bacteroidetes (2.40-9.22%) present in the gut of E. eugeniae. The alpha diversity (Observed species, Chao1, ACE, Shannon, Simpson, and Fisher alpha) indices showed that OAFS had significantly higher alpha diversity than AS and CAFS groups. The core microbiota analysis showed that OAFS and AS groups had a relatively similar bacterial panel in comparison to the CAFS group. Various statistical tools i.e. MetagenomeSeq, LEfSe, and Random Forest analysis were performed and the findings demonstrated prevalence of the most significant bacterial genera; Aeromonas, Gaiella, and Burkholderia in CAFS group. Nonetheless, in AS and OAFS groups, the common existence of Anaerosporobacter and Aquihabitans were found respectively. Metagenomic functional prediction revealed that earthworms' gut microbial communities were actively involved in multiple organic and xenobiotics compound degradation-related pathways. This is the first research to use high-throughput 16S rRNA gene amplicon sequencing to show the gut microbiota of E. eugeniae in diverse agricultural systems. The findings suggest the configuration of the gut microbiota of earthworms and its potential role in the soil ecosystem depends on the microbial communities of the soil.

Inonotus obliquus aqueous extract prevents histopathological alterations in liver induced by environmental toxicant Microcystin.

Environmental toxicants like microcystins are known to adversely impact liver physiology and lead to the increased risk for abnormal liver function and even liver carcinoma. Chaga mushroom (Inonotus obliquus) is reported for various properties mainly antibacterial, antiallergic, anti-inflammatory, antioxidant, and anticancer properties. This study was aimed to assess the effect microcystin (MC-LR) on histopathology of liver in mice and a preventive measure by using aqueous extract of Inonotus obliquus (IOAE). Adult Balb/c mice were administered with MC-LR at 20 â€‹µg/kg body weight, per day, intraperitoneal (i.p.) for 4 weeks. IOAE was treated to one group of MC-LR mice at 200 â€‹mg/kg body weight, per oral, for 4 weeks. Histological staining for liver structural details and biochemical assays for functions were assessed. The results of the study showed that MC-LR drastically reduced the body weight of mice which were restored close to the range of control by IOAE treatment. MC-LR exposed mice showed 1.9, 1.7 and 2.2-fold increase in the levels of SGOT, SGPT and LDH which were restored by IOAE treatment as compared to control (one-fold). MC-LR exposed mice showed reduced level of GSH (19.83 â€‹± â€‹3.3 â€‹µM) which were regained by IOAE treatment (50.83 â€‹± â€‹3.0 â€‹µM). Similar observations were noted for catalase activity. Histological examinations show that MC-LR exposed degenerative changes in the liver sections which were restored by IOAE supplementation. The immunofluorescence analysis of caspase-3 counterstained with DAPI showed that MC-LR led to the increased expression of caspase-3 which were comparatively reduced by IOAE treatment. The cell viability decreased on increasing the concentration of MC-LR with 5% cell viability at concentration of 10 â€‹µg MC-LR/mL as that of control 100% Cell viability. The IC50 was calculated to be 3.6 â€‹µg/ml, indicating that MC-LR is chronic toxic to AML12 mouse hepatocytes. The molecular docking interaction of NF-κB-NIK with ergosterol peroxidase showed binding interaction between the two and showed the plausible molecular basis for the effects of IOAE in MC-LR induced liver injury. Collectively, this study revealed the deleterious effects of MC-LR on liver through generation of oxidative stress and activation of caspase-3, which were prevented by treatment with IOAE.

Genetic engineering of potato (Solanum tuberosum L.) for enhanced α-tocopherols and abiotic stress tolerance.

Vitamin E (α-tocopherol) is a lipid-soluble essential vitamin recognized for improvement in degenerative health conditions, abating cancer risk, and coronary heart diseases in humans. While in plants, it acts as a free radical scavenger that protects cells against oxidative and photooxidative damages. The daily consumption of potato makes it a key target for biofortification with vitamins for eliminating vitamin deficiency in large populations. Vitamin E biosynthetic pathway genes have been overexpressed in plants via genetic engineering to enhance the α-tocopherol content. Major genes involved in the vitamin E biosynthesis in plants viz. the homogentisate-phytyltransferase (At-HPT) and γ-tocopherol-methyltransferase (At-γ-TMT), isolated from Arabidopsis were constitutively overexpressed in potato (Solanum tuberosum L.). The molecular analyses of independent transgenic lines revealed a stable integration of both the genes in the plant genome. The transgenic potato exhibited significantly improved vitamin E contents up to 173-258% in comparison to the untransformed control plants. Transgenic tissues also exhibited increased cellular antioxidant enzymes, proline, osmolyte, and glutathione content that are directly correlated with the ability of the plant to withstand abiotic stresses imposed by salt (NaCl) and heavy metal (CdCl2 ). Therefore, the current strategy of increasing the vitamin E content in potato with enhanced tolerance to abiotic stresses might greatly aid efforts to engineer crops for human health benefits and greater yield under adverse environmental conditions.

ADH1B, ALDH2, GSTM1 and GSTT1 Gene Polymorphic Frequencies among Alcoholics and Controls in the Arcadian Population of Central India

Background: Epidemiological research has highlighted the global burden of primary liver cancer cases due to alcohol consumption, even in a low consumption country like India. Alcohol detoxification is governed by ADH1B, ALDH2, GSTM1 and GSTT1 genes that encode functional enzymes which are coordinated with each other to remove highly toxic metabolites i.e. acetaldehyde as well as reactive oxygen species generated through detoxification processes. Some communities in the population appears to be at greater risk for development of the liver cancer due to genetic predispositions. Methods: The aim of this study was to screen the arcadian population of central India in order to investigate and compare the genotype distribution and allele frequencies of alcohol metabolizing genes (ADH1B, ALDH2, GSTM1 and GSTT1) in both alcoholic (N=121) and control (N=145) healthy subjects. The gene polymorphism analysis was conducted using PCR and RFLP methods. Results: The allele frequency of ALDH2 *1 was 0.79 and of ALDH2*2 was 0.21 (OR:1.12; CI (95%): 0.74-1.71). The null allele frequency for GSTM1 was 0.28 (OR:0.85; CI (95%): 0.50-1.46) and for GSTT1 was 0.20 (OR:1.93; CI (95%): 1.05-3.55). No gene polymorphism for ADH1B was not observed. The total prevalence of polymorphisms was 3.38% for ALDH2, GSTM1 and GSTT1. Conclusion: The results of this study suggested that individuals of the Central India population under study are at risk for liver disorders due to ALDH2, GSTM1 and GSTT1 gene polymorphisms. This results may have significance for prevention of alcohol dependence, alcoholic liver disorders and the likelihood of liver cancer.

Contribution of Vesicular Glutamate Transporters to Stress Response and Related Psychopathologies: Studies in VGluT3 Knockout Mice.

Maintenance of the homeostasis in a constantly changing environment is a fundamental process of life. Disturbances of the homeostatic balance is defined as stress response and is induced by wide variety of challenges called stressors. Being the main excitatory neurotransmitter of the central nervous system glutamate is important in the adaptation process of stress regulating both the catecholaminergic system and the hypothalamic-pituitary-adrenocortical axis. Data are accumulating about the role of different glutamatergic receptors at all levels of these axes, but little is known about the contribution of different vesicular glutamate transporters (VGluT1-3) characterizing the glutamatergic neurons. Here we summarize basic knowledge about VGluTs, their role in physiological regulation of stress adaptation, as well as their contribution to stress-related psychopathology. Most of our knowledge comes from the VGluT3 knockout mice, as VGluT1 and 2 knockouts are not viable. VGluT3 was discovered later than, and is not as widespread as the VGluT1 and 2. It may co-localize with other transmitters, and participate in retrograde signaling; as such its role might be unique. Previous reports using VGluT3 knockout mice showed enhanced anxiety and innate fear compared to wild type. Moreover, these knockout animals had enhanced resting corticotropin-releasing hormone mRNA levels in the hypothalamus and disturbed glucocorticoid stress responses. In conclusion, VGluT3 participates in stress adaptation regulation. The neuroendocrine changes observed in VGluT3 knockout mice may contribute to their anxious, fearful phenotype.

Biotechnological improvement of nutritional and therapeutic value of cultivated potato.

Genetic engineering is recognized as a powerful tool for altering the genetic characteristic of crop plants. Genetic engineering has tremendous potential in developing improved potato varieties with desired agronomic traits and has been utilized for improvement of several crop plants including potato to enhance essential amino acid, protein and lipids/carbohydrates contents as well to improve stress tolerance. The pathway engineering of amino acid revealed dramatic changes in essential amino acid content and protein quality. Similarly, the vitamin pathway engineering of potato has been proved to enhance the vitamin content with increased cellular antioxidant activities. Secondary metabolites such as flavonoids have also been altered through the genetic engineering of potato. This review provides detailed reports on the advances made in genetic transformation of potato for enrichment in its nutritional and therapeutic value by an increase in functional secondary metabolites, carbohydrate, essential amino acids, proteins, lipids, vitamins and edible vaccines.

Molecular Links between Alcohol and Tobacco Induced DNA Damage, Gene Polymorphisms and Patho-physiological Consequences: A Systematic Review of Hepatic Carcinogenesis.

Chronic alcohol and tobacco abuse plays a crucial role in the development of different liver associated disorders. Intake promotes the generation of reactive oxygen species within hepatic cells exposing their DNA to continuous oxidative stress which finally leads to DNA damage. However in response to such damage an entangled protective repair machinery comprising different repair proteins like ATM, ATR, H2AX, MRN complex becomes activated. Under abnormal conditions the excessive reactive oxygen species generation results in genetic predisposition of various genes (as ADH, ALDH, CYP2E1, GSTT1, GSTP1 and GSTM1) involved in xenobiotic metabolic pathways, associated with susceptibility to different liver related diseases such as fibrosis, cirrhosis and hepatocellular carcinoma. There is increasing evidence that the inflammatory process is inherently associated with many different cancer types, including hepatocellular carcinomas. The generated reactive oxygen species can also activate or repress epigenetic elements such as chromatin remodeling, non-coding RNAs (micro-RNAs), DNA (de) methylation and histone modification that affect gene expression, hence leading to various disorders. The present review provides comprehensive knowledge of different molecular mechanisms involved in gene polymorphism and their possible association with alcohol and tobacco consumption. The article also showcases the necessity of identifying novel diagnostic biomarkers for early cancer risk assessment among alcohol and tobacco users.

Mitochondrial oxidative stress-induced epigenetic modifications in pancreatic epithelial cells.

Emerging studies have linked prooxidative carbamate compound exposures with various human pathologies including pancreatic cancer. In these studies, our aim was to examine mitochondrial oxidative stress-mediated aberrant chromatin responses in human pancreatic ductal epithelial cells. Posttranslational histone modifications, promoter DNA methylation, and micro-RNA (miRNA) expression patterns were evaluated following induction of mitochondrial oxidative stress by N-succinimidyl N-methylcarbamate exposure. In treated cells, perturbation in mitochondrial machinery led to hypermethylation of p16 and smad4 gene promoters and downregulation of respective gene products. Posttranslational histone modifications that include hypoacetylation of acetylated histone (AcH) 3 and AcH4, hypermethylation of monomethylated histone 3 at lysine 9 and trimethylated histone 4 at lysine 20 ubiquitinated histone (uH) 2A/uH2B, and increased phosphorylation of H2AX and H3 were observed in the treated cells. Altered expression of miRNAs denoted possible location of corresponding genes at oxidatively damaged fragile sites. Collectively, our results provide a direct role of mitochondrial oxidative stress-mediated epigenetic imbalance to perturbed genomic integrity in oxygen radical-induced pancreatic injury. Further, identification and characterization of molecular switches that affect these epigenomic signatures and targets thereof will be imperative to understand the complex role of redox-regulatory network in pancreatic milieu.

In vitro and in vivo evaluation of the anticarcinogenic and cancer chemopreventive potential of a flavonoid-rich fraction from a traditional Indian herb Selaginella bryopteris.

Prevention of cancer through nutritional intervention has gained significant recognition in recent years. Evidence revealed from mechanistic investigations coupled with molecular epidemiology show an inverse association of dietary flavonoids intake with cancer risk. The chemopreventive and anticarcinogenic potential of Selaginella bryopteris, a traditional Indian herb referred to as 'Sanjeevani' in the Ayurvedic system of medicine, was examined in the present study. Comprehensive in vitro and in vivo studies were conducted on the flavonoid-rich benzene fraction of the aqueous extract that demonstrated a significant cytoprotective activity. Biomarkers of chemoprevention such as proliferative index and status of cell-cycle regulatory proteins, antioxidant property, anti-inflammatory effect, reversal of stress-induced senescence and genoprotective effect were investigated in human and murine cell cultures. Chemopreventive potential was assessed in benzopyrene-induced lung carcinogenesis and 7,12-dimethyl benz(a)anthracene-mediated skin papillomagenesis test models. Inhibition of DNA fragmentation, unperturbed cell-cycle regulation, maintenance of intracellular antioxidant defence, anti-inflammatory activity, prevention of stress-induced senescence and genoprotective effects against methyl isocyanate carcinogenicity was observed. Medium-term anticarcinogenicity and two-stage skin papillomagenesis tests strongly substantiated our in vitro observations. Results from the present study provide evidence of anticarcinogenic and chemopreventive activities of S. bryopteris hitherto unreported and reaffirm the nutritional significance of flavonoids in cancer prevention.

Molecular mechanisms of isocyanate induced oncogenic transformation in ovarian epithelial cells.

Ovarian surface epithelium is under constant physiological pressure to maintain its integrity. Environmental toxic exposure can contribute to degenerative pathologies including ovarian cancer. Based on our current understanding, we aimed at listing mechanistic insights that contribute to ovarian carcinogenesis after exposure to methyl isocyanate, an ubiquitous environmental pollutant. Ovarian epithelial cells manifested a persistent DNA damage response along with increased accumulation of GADD45, p21, p16(INK4A) and pRb proteins upon treatment. Increase in cell size and ß-gal positive staining showing inception of premature senescence with morphological transformation and structural and numerical chromosomal abnormalities were also observed. Immuno-FISH analysis illustrated early loss of TRF2 protein suggestive of telomeric dysfunction due to premature senescence and plausible association with chromosomal and microsatellite instability. Soft-agar assay displayed neoplasticity in treated cells demonstrating onset of malignant transformation. These results indicate that isocyanate exposure alters ovarian epithelial cell proliferation and might lead to ovarian dysfunction and carcinogenesis.

Molecular characterization of isocyanate-induced male germ-line genomic instability.

Male reproductive health is exquisitely sensitive to environmental insults as evidenced by the rising incidence of testicular cancers and low and probably declining semen quality. Isocyanates, such as methyl isocyanate (MIC), with their wide industrial applications, are known to exert severe ill health effects. The present study was performed to find out the pathophysiological implications of isocyanate exposure on the male germ line. The investigations were performed in the cultured mouse spermatogonial GC-1 spg cell line using N-succinimidyl N-methylcarbamate, a surrogate chemical to MIC. DNA damage, oxidative stress and apoptosis response parameters increased with time of exposure and dose after treatment. Treated cells also displayed elevated levels of inflammatory cytokines as well as morphological transformation and stress-responsive senescence. Chromosomal aberrations, telomere anomaly, aneuploidy and variable amplification of microsatellite repeats additionally indicated induced genomic instability. This was accompanied by evidence of a deregulation of cell cycle progression, such as substantial fold-changes in the expression of proliferating cell nuclear antigen, Cyclin D1, Bcl-2 and Bax genes; and aberrant expression of p53, cyclin A, cyclin E, CDK-2 and aurora kinase-B proteins. Our results demonstrate that MIC in the form of N-succinimidyl N-methylcarbamate promotes germ-line genomic instability in vitro. We envisage that understanding the interplay between environmental toxin-induced signaling and predisposition to testicular cancers would spur identification of meaningful targets for useful therapeutic translational modalities.

The stimuli-specific role of vasopressin in the hypothalamus-pituitary-adrenal axis response to stress.

Adaptation to a constantly changing environment is fundamental to every living organism. The hypothalamic-pituitary-adrenocortical (HPA) axis is a key component of the adaptation process. The present study tests the hypothesis that vasopressin (AVP) is required for the HPA response to acute stimuli. To accomplish this, naturally AVP-deficient Brattleboro rats were exposed to a wide range of stimuli and their HPA response was compared with heterozygous littermates. The circadian rhythmicity of plasma ACTH and corticosterone was not different between the two genotypes. The ACTH and corticosterone response to volume load, restraint or aggressive attack were decreased in AVP-deficient rats. The stress-induced increase in ACTH, but not corticosterone, was significantly impaired in AVP-deficient animals after novelty, elevated plus-maze, forced swim, hypoglycaemia, ulcerogenic cold immobilisation, lipopolysaccharide, hypertonic saline and egg white injection. The HPA response to social avoidance, ether inhalation and footshock was not different between the genotypes. In vitro, the hypophysis of AVP-deficient animals showed a reduction in stimulated ACTH production and their adrenal glands were hyporeactive to ACTH. A dissociation between the ACTH and corticosterone response was observed in several experiments and could not be explained by an earlier ACTH peak or enhanced adrenal sensitivity, suggesting the existence of paraadenohypophyseal neuroendocrine regulators. Loss of AVP affected the HPA response to a wide variety of stressors. Interestingly, the contribution of AVP to the HPA response was not specific for, nor limited to, a known stressor category. Thus, there is a context-specific requirement for AVP in stress-induced activation of the HPA axis.

Analysis of cellular response to isocyanate using N-succinimidyl N-methylcarbamate exposure in cultured mammalian cells.

Isocyanates (R--N==C==O), one of the highly reactive industrial intermediates, possess the capability to modulate the bio-molecules by forming toxic metabolites and adducts which may cause adverse health effects. Some of their toxic degradations have previously been unknown and overlooked; of which, molecular repercussions underlying their genetic hazards upon occupational/accidental exposures still remain as an intricate issue and are hitherto unknown. To assess the genotoxic potential of methyl isocyanate in cultured mammalian cells after in vitro exposure, we performed a study in three different normal cell lines MM55.K (mouse kidney epithelial), B/CMBA.Ov (mouse ovarian epithelial), and NIH/3T3 (primary mouse embryonic fibroblast). Cellular DNA damage response was studied for qualitative phosphorylation states of ATM, gammaH2AX proteins and quantitative state of p53 phosphorylation; DNA cell cycle analysis and measure of cellular apoptotic index before and after treatment were also investigated. Our results demonstrate that methyl isocyanate by negatively regulating the DNA damage response pathway, might promote cell cycle arrest, and apoptosis in cultured mammalian cells suggestive of causing genetic alterations. We anticipate that these data along with other studies reported in the literature would help to design better approaches in risk assessment of occupational and accidental exposure to isocyanates. We also predict that increasing knowledge on DNA damage-triggered signaling leading to cell death could provide new strategies for investigating the effects of DNA repair disorders and decreased repair capacity on the toxicity and carcinogenic properties of environmental toxins.

Isocyanates induces DNA damage, apoptosis, oxidative stress, and inflammation in cultured human lymphocytes.

Isocyanates, a group of low molecular weight aromatic and aliphatic compounds containing the isocyanate group (-NCO), are important raw materials with diverse industrial applications; however, pathophysiological implications resulting from occupational and accidental exposures of these compounds are hitherto unknown. Although preliminary evidence available in the literature suggests that isocyanates and their derivatives may have deleterious health effects including immunotoxicity, but molecular mechanisms underlying such an effect have never been addressed. The present study was carried out to assess the immunotoxic response of methyl isocyanate (MIC) on cultured human lymphocytes isolated from healthy human volunteers. Studies were conducted to evaluate both dose-dependent and time-course response (n = 3), using N-succinimidyl N-methylcarbamate, a surrogate chemical substitute to MIC. Evaluation of DNA damage by ataxia telangiectasia mutated (ATM) and gamma H2AX protein phosphorylation states; measure of apoptotic index through annexin-V/PI assay, apoptotic DNA ladder assay, and mitochondrial depolarization; induction of oxidative stress by CM-H2DCFDA and formation of 8-hydroxy-2' deoxy guanosine; levels of antioxidant defense system enzyme glutathione reductase; and multiplex cytometric bead array analysis to quantify the secreted levels of inflammatory cytokines, interleukin-8, interleukin-1beta, interleukin-6, interleukin-10, tumor necrosis factor, and interleukin-12p70 parameters were carried out. The results of the study showed a dose- and time-dependent response, providing evidence to hitherto unknown molecular mechanisms of immunotoxic consequences of isocyanate exposure at a genomic level. We anticipate these data along with other studies reported in the literature would help to design better approaches in risk assessment of occupational and accidental exposure to isocyanates.