Incidence of microplastics in Indian anchovy Stolephorus indicus from Tuticorin, Southeast coast of India.

In the present study, the occurrence of microplastics (MPs) in the gut, gill, and muscle of edible fish Stolephorus indicus sampled from Tuticorin coastal regions of Tamilnadu, India was investigated. We recorded a total of 689 MPs which includes 510 and 179 MPs from males and females respectively. The total abundance of MPs was significantly (P < 0.05) higher in the gut followed by gills and muscle. The sex-wise distribution of average MPs showed high in the females' gut and compared to that in males. Further, the length wise distribution of MPs was higher in the muscle in both male and female fish, followed by other organs. The predominance of MPs in tissues were transparent and blue colour with fibers and fragments in both males and females. Besides, polyethylene terephthalate and nylon were evidenced by the Fourier-transform infrared spectroscopy spectrum in all organs of fishes.

Evaluating the ameliorative effect of nano bis-demethoxy curcumin analog against extrapulmonary toxicity in rat induced by inhaled multi-walled carbon nanotube.

Carbon nanotubes (CNTs) exposure in human beings through inhalation may affect pulmonary organs and extrapulmonary organs including liver, kidney, brain, spleen, etc. The toxic effects developed as the result of CNTs exposure made us to explore the beneficial effect of nano bis-demethoxy curcumin analog (NBDMCA) towards multi-walled carbon nanotubes (MWCNTs)-induced toxicity in extrapulmonary organs. The current study described the ameliorative effect of NBDMCA against the toxic effects developed by inhaled MWCNTs in the extrapulmonary organs. The rats are exposed to the fixed aerosol concentration of 5 mg/m3 maintained in inhalation exposure chambers MWCNTs for 15 days as per OECD guidelines. After the exposure with MWCNTs, the animals were treated with NBDMCA (5 mg/kg body weight) with different dose frequencies, i.e., 2 doses per week for 1, 2, and 4 weeks. After treatment duration, the blood was drawn from retro-orbital vein and subjected to biochemical and cytokine analysis. Further the animals were euthanized, and the sample tissues were collected and performed oxidative stress and histopathology. The study results revealed that the intravenous administration of NBDMCA suppresses the extrapulmonary toxicity induced by MWCNTs, i.e., annulling the clinical changes and oxidative stress in various extrapulmonary organs at low doses of NBDMCA, evidenced its antioxidant efficacy. Moreover, use of increased doses provides better reduction in toxic symptoms with negligible side effects confirming the dose-dependent efficacy of NBDMCA. Overall, we suggested that NBDMCA may materialize into an effective compound for the reduction of MWCNTs-induced toxicity.

Multi-walled carbon nanotube-induced inhalation toxicity: Recognizing nano bis-demethoxy curcumin analog as an ameliorating candidate.

Human beings and ecosystems are being possibly exposed to CNTs, as there is a rise in global production rate of carbon nanotubes (CNTs). This may affect the health of humans and increases the environmental risk. We have already reported the pulmonary toxicity due to the inhalation of MWCNTs. We claim that a compound with anti-inflammatory and antioxidant activity may ameliorate the CNT-induced toxic effect. With this view, we have investigated the ameliorative effect of intravenously-administered nano bis-demethoxy curcumin analog (NBDMCA) against MWCNTs-induced inhalation toxicity by examining the lung histopathology for inflammatory cell dynamics, pulmonary remodeling and estimating the inflammatory biomarkers in the broncho-alveolar lavage fluid. We observed that NBDMCA could ameliorate the injury as evidenced by the decline in the levels of markers of inflammation, cell damage, and the histopathological changes induced by MWCNTs. We conclude that NBDMCA may be used to reduce the risk of MWCNTs-induced inhalation toxicity.

Future of nano bisdemethoxy curcumin analog: guaranteeing safer intravenous delivery.

The present study deals with the toxicity assessment of NBDMCA in vitro using red cell model and in vivo using rat model. Hemolysis was used as toxicity index in red blood cells. Different concentrations of NBDMCA viz., 20, 40, 60, 80, 100µg/ml in PBS were incubated with the red blood cells of rat. NBDMCA was found to induce less than 3% hemolysis in intact erythrocytes which was far lesser than the accepted threshold of 5%. Hematological cum biochemical parameters along with histopathological analysis and hemolysis were used as toxicity indices in rats. Whole blood of the NBDMCA-treated rats and control rats were analyzed for hematological parameters: erythrocyte count, leukocyte count, leukocyte differential count, hemoglobin, hematocrit, mean cell volume (MCV), mean corpuscular hemoglobin (MCH) using fully automated hematology analyzer. All hematological parameters analyzed were within the normal values in both the groups. Plasma samples were analyzed for biochemical parameters including glucose, blood urea nitrogen (BUN), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatinine (Cre), albumin (Alb), total protein (TP), calcium (Ca) and phosphorus (P) using fully automated biochemistry analyzer. Invariably, all the biochemical parameters are significantly similar in both the groups. Gross examination of vital organs like lung, heart, kidney, spleen and brain reveals no detectable abnormalities in NBDMCA-treated animals. Internal organs like heart, brain, lung, liver, spleen and kidneys of the experimental animals were collected and fixed in 10% formalin, processed in vacuum infiltration tissue processor, embedded with paraffin wax and sectioned at approximately 5µm thick, stained with hematoxylin and eosin. The sections were examined and imaged through light microscopy. NBDMCA did not produce any significant changes in the histoarchitecture of all the organs studied. Heart, aorta, brain, lung, liver, kidney and spleen showed normal pathology report. The histopathological data correlated with the biochemical results indicating normal hepatocellular and nephrotic function. Our investigation clearly revealed that NBDMCA is hemocompatible in vitro and also safe to vital organs in vivo. We conclude that NBDMCA is non-toxic and safe and can be promoted as an ideal therapeutic tool for human use.

One time nose-only inhalation of MWCNTs: Exploring the mechanism of toxicity by intermittent sacrifice in Wistar rats.

We have investigated the time-dependent effect of multi-walled carbon nanotubes (MWCNTs) in rats upon single inhalation exposure followed by intermittent sacrifice. The effects were monitored by analyzing the bronchoalveolar lavage fluid (BALF) and histopathological analysis. Cell count, neutrophils, lymphocytes, lactate dehydrogenase, alkaline phosphatase, protein and cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 4 (IL-4)) were significantly increased, while cell viability and alveolar macrophage count significantly decreased in the BALF of MWCNT-treated rats on day 1, day 7 and day 14 post-exposure, when compared to control rats. Histopathological analysis revealed inflammation, fibrosis and granuloma in the lungs of MWCNTs-treated rats on day 7 and day 14 post-exposure. We interpret that MWCNT induces inflammation, fibrosis and granuloma characterized by progressive elevation of TNF-α and IL-4. Histopathological studies further support our view and reveal the distribution of MWCNT in lungs and tracheobronchial lymph nodes (TBLN). We conclude that MWCNT-induced pulmonary toxicity is considerable even on single exposure.

Toxicity and bio-accumulation of inhaled cerium oxide nanoparticles in CD1 mice.

Male CD1 mice were subjected to nose-inhalation exposure of CeO2 nanoparticles (NPs) for 0, 7, 14 or 28 days with 14 or 28 days of recovery time at an aerosol concentration of 2 mg/m(3). Markers of lung injury and pro-inflammatory cytokines (interleukin-1beta, tumour necrosis factor-alpha, interleukin-6 and macrophage inflammatory protein-2) in bronchoalveolar lavage fluid (BALF), oxidative stress in lungs, bio-accumulation, and histopathology of pulmonary and extrapulmonary tissues were assessed. BALF analysis revealed the induction of pulmonary inflammation, as evident by an increase in the influx of neutrophils with a significant secretion of pro-inflammatory cytokines that lead to generation of oxidative stress and cytotoxicity, as is evident by induction of lipid peroxidation, depletion of glutathione and increased BALF lactate dehydrogenase and protein. The histopathological examination revealed that these inhaled CeO2 NPs were located all over the pulmonary parenchyma, inducing a severe, chronic, active inflammatory response characterised by necrosis, proteinosis, fibrosis and well-formed discrete granulomas in the pulmonary tissue and tubular degeneration leading to coagulative necrosis in kidneys. Inductively coupled plasma optical emission spectrometer results showed a significant bio-accumulation of these particles in the pulmonary and extrapulmonary tissues, even after one month of post-inhalation exposure. Together, these findings suggest that inhalation exposure of CeO2 NPs can induce pulmonary and extrapulmonary toxicity.

Toxicity of zinc oxide nanoparticles through oral route.

This experiment was aimed to determine the significance of dose by comparing acute oral toxicological potential of nano-sized zinc oxide (20 nm) with its micro-sized zinc oxide. Sprague Dawley rats, 8 to 9 weeks old, were administered with 5, 50, 300, 1000 and 2000 mg/kg body weight (b.w.) of nano- and micro-sized zinc oxide suspended in distilled water once through oral gavage. The effects of the micro- and nano-sized zinc oxide on biochemical and hematological parameters were analyzed on day 14 of administration. The organs were collected for histopathology. Interestingly, inverse dose-dependent increase was noted in aspartate aminotransferase, alanine aminotransferase serum levels of nano-size zinc oxide groups when compared with their micro-sized zinc oxide. Clotting time was effected in all the male groups of nano-size zinc oxide, except in 1000 mg/kg b.w. The incidences of microscopic lesions in liver, pancreas, heart and stomach were higher in lower doses of nano-size zinc oxide compared to higher dose. However, the incidences of above lesions were higher in rats treated with a high dose of micro-sized zinc oxide. We conclude that nano-size zinc oxide exhibited toxicity at lower doses, thus alarming future nanotoxicology research needs to be focused on importance of dose metrics rather following the conventional methods while conducting in vivo experiments.