phalloidine and Necrosis

Topics: Animals; Calcium; Carbon Tetrachloride; Cell Membrane; Chemical and Drug Induced Liver Injury; Galactosamine; In Vitro Techniques; Liver; Liver Diseases; Necrosis; Phalloidine; Rats

Cigarette smoke extracts (CSE) may play a significant role in diseases of the upper airway including chronic rhinosinusitis. Even short term exposure of cigarette smoke has adverse effects on mitochondrial functions and redox homeostasis in tissues which may progress to further complications associated with chronic smoking. Cigarette smoke alters toll-like receptor 4 (TLR4) expression and activation in bronchial epithelial cells. Carbocysteine is an anti-oxidant and mucolytic agent. The effects of carbocysteine on CSE induced oxidative stress and on associated innate immune and inflammatory responses in nasal epithelial cells are largely unknown. The present study was aimed to assess in CSE stimulated nasal epithelial cells (RPMI 2650) the effects of carbocysteine (10(-4)M) on: cell survival, intracellular reactive oxygen species (ROS) production, TLR4 expression, LPS binding and neutrophil chemotaxis (actin reorganization). We found that CSE increased ROS production, TLR4 expression, LPS binding and neutrophil chemotaxis and all these events were counteracted by pre-incubating CSE stimulated RPMI 2650 cells with carbocysteine. In conclusion, the present study provides compelling evidence that carbocysteine may be considered a promising therapeutic strategy in chronic inflammatory nasal diseases.

Topics: Actins; Apoptosis; Carbocysteine; Cell Line; Cell Separation; Epithelial Cells; Expectorants; Fluorescent Antibody Technique; Humans; Immunity, Innate; Lipopolysaccharides; Nasal Mucosa; Necrosis; Neutrophils; Nicotiana; Oxidative Stress; Phalloidine; Reactive Oxygen Species; Smoke; Tobacco Products; Toll-Like Receptor 4

Mineral fibers are potential carcinogens to humans. In order to help clarify the etiology of the pathological effects of asbestos, cellular reactions to natural and synthetic asbestos fibers were compared using a lung alveolar cancer cell line (A549 epithelial cells), considered the first target of inhaled micro-environmental contaminants. Natural asbestos tremolite (NAT) fibers were collected from rocks in NW Italy. Synthetic asbestos tremolite (SAT) was iron-free and therefore considered as standard tremolite. Both fibers, subjected to mineralogical characterization by X-ray powder diffractometry, electron microscopy and energy dispersive spectrometry, fell within the definition of respirable and potentially carcinogenic fibers. Several signs of functional and structural cell damage were found after treatment with both fibers, documented by viability, motility, and morphological perturbations. Phalloidin labeling showed irregular distribution of cytoskeletal F-actin, whereas immunohistochemical investigations showed abnormal expression of VEGF, Cdc42, β-catenin, assessed as risks indicators for cancer development. Both fibers caused significant loss of viability, even compared to UICC crocidolite, but, while SAT fibers exerted a more direct cytotoxic effect, survival of damaged cells expressing high VEGF levels was detected after NAT contact. This in vitro pilot study outlines potential health risks of NAT fibers in vivo related to their iron content, which could trigger signaling networks connected with cell proliferation and neoplastic transformation.

Topics: Actins; Apoptosis; Asbestos; Asbestos, Amphibole; Asbestos, Crocidolite; beta Catenin; cdc42 GTP-Binding Protein; Cell Line, Tumor; Cell Survival; Cytoskeleton; Humans; Immunohistochemistry; Iron; Microscopy, Electron; Mitosis; Necrosis; Phalloidine; Pilot Projects; Tetrazolium Salts; Thiazoles; Time Factors; Vascular Endothelial Growth Factor A; X-Rays

The Wong-Kilbourne derivative of Chang conjunctiva-derived cell line has been widely used for toxicological and functional in vitro studies on the ocular surface. The common reserve to this cell line is the reported contamination with HeLa cells. Thus, the IOBA-NHC spontaneously immortalized conjunctival epithelial cell line has been recently developed and did not show other cell type contamination. Our purpose was to determine whether both cell lines would be equally suitable for in vitro toxicological studies. Therefore, we compared in these two cell types the toxic effects of the preservative, benzalkonium chloride (BAC); its toxicity has been often reported on conjunctival in vivo and in vitro models.. The necrotic, apoptotic, and oxidative effects of BAC were evaluated on Chang and IOBA-NHC cell lines using microplate cytofluorometry tests (neutral red, 2,7- dichlorofluorescein diacetate dye [H(2)DCF-DA], hydroethidine, and Yopro-1), flow cytometry (Annexin V/7-AAD and DNA content tests), and standard immunofluorescence stainings. Cells were exposed to five concentrations of BAC (10(-2)%, 5.10(-3)%, 10(-3)%, 10(-4)%, and 10(-5)%) for two incubation times: 15 min of treatment and 15 min of treatment followed by 24 h of cell recovery in complete medium.. All parameters of toxicity increased in a BAC dose-dependent manner on both cell lines.. The comparison of BAC toxicity on both cell lines supported the use of IOBA-NHC and Chang cells for toxicological in vitro studies. Drawbacks of both cell lines have to be known and considered in studies performed on these cell lines.

Topics: Annexin A5; Benzalkonium Compounds; Cell Death; Cell Line; Cell Membrane; Cell Survival; Conjunctiva; DNA; Fluoresceins; Humans; Necrosis; Phalloidine; Propidium; Reactive Oxygen Species; Superoxides

In alcoholic liver injury, necrosis is involved in the progression from benign fatty liver to alcoholic hepatitis and cirrhosis. However, there is no practical model of alcohol-dependent liver cell necrosis. The calcium-dependent killing of cultured rat hepatocytes by two different membrane-active hepatotoxins, galactosamine and phalloidin, is potentiated by ethyl alcohol. This indicates that some general physical effect of alcohol on cellular membranes renders cells susceptible to otherwise nonlethal injuries. The in vitro model described in this report may thus be used to search for a general mechanism underlying alcohol-related tissue injury.

Topics: Animals; Calcium; Cell Membrane; Cells, Cultured; Drug Synergism; Ethanol; Female; Galactosamine; In Vitro Techniques; Liver; Liver Diseases, Alcoholic; Necrosis; Phalloidine; Rats

Topics: Animals; Chemical and Drug Induced Liver Injury; Hemorrhage; Intestine, Small; Lung; Necrosis; Oligopeptides; Phalloidine; Rats; Shock, Hemorrhagic

Topics: Animals; Animals, Newborn; Chemical and Drug Induced Liver Injury; Hemorrhage; Liver; Liver Regeneration; Male; Necrosis; Oligopeptides; Phalloidine; Rats; Thymidine; Tritium

In vitro 14C-Methyl-Phalloidin is found to be well dialysable; in vivo dialysis is less effective. In rats the application of 2 mg/kg Phalloidin i.v. led to death after 106 minutes on the average. Hemodialysis with electrolyte-glucose solution or with plasma protein solution immediately started after Phalloidin injection did not alter the survival time significantly. Only a group of rats which was cross dialysed immediately after intoxication showed a statistically insignificant prolongation of survival time of 16 minutes. The histomorphological findings of the liver were similar in all groups. We found a phalloidinic vacuolisation of the cytoplasm of the lobular periphery, hemorrhagic necrosis and also fatty changes in the periphery of the lobule with small fat droplets and pycnosis of nuclei. Specific Phalloidin effects, too, were found in the liver of both animals used in cross-dialysis, which proves that Phalloidin is dialysable by this method.

Topics: Animals; Arteriovenous Shunt, Surgical; Blood Glucose; Blood Proteins; Fatty Liver; Female; Glucose; In Vitro Techniques; Liver; Necrosis; Oligopeptides; Phalloidine; Rats; Renal Dialysis