Induction Of Cell Damage Research Articles

Fungal burden, dimorphic transition and candidalysin: Role in Candida albicans-induced vaginal cell damage and mitochondrial activation in vitro.

Candida albicans (C. albicans) can behave as a commensal yeast colonizing the vaginal mucosa, and in this condition is tolerated by the epithelium. When the epithelial tolerance breaks down, due to C. albicans overgrowth and hyphae formation, the generated inflammatory response and cell damage lead to vulvovaginal candidiasis (VVC) symptoms. Here, we focused on the induction of mitochondrial reactive oxygen species (mtROS) in vaginal epithelial cells after C. albicans infection and the involvement of fungal burden, morphogenesis and candidalysin (CL) production in such induction. Bioluminescent (BLI) C. albicans, C. albicans PCA-2 and C. albicans 529L strains were employed in an in vitro infection model including reconstituted vaginal epithelium cells (RVE), produced starting from A-431 cell line. The production of mtROS was kinetically measured by using MitoSOX™ Red probe. The potency of C. albicans to induced cell damage to RVE and C. albicans proliferation have also been evaluated. C. albicans induces a rapid mtROS release from vaginal epithelial cells, in parallel with an increase of the fungal load and hyphal formation. Under the same experimental conditions, the 529L C. albicans strain, known to be defective in CL production, induced a minor mtROS release showing the key role of CL in causing epithelial mithocondrial activation. C. albicans PCA-2, unable to form hyphae, induced comparable but slower mtROS production as compared to BLI C. albicans yeasts. By reducing mtROS through a ROS scavenger, an increased fungal burden was observed during RVE infection but not in fungal cultures grown on abiotic surface. Collectively, we conclude that CL, more than fungal load and hyphae formation, seems to play a key role in the rapid activation of mtROS by epithelial cells and in the induction of cell-damage and that mtROS are key elements in the vaginal epithelial cells response to C. albicans.

Effects of Common Food Additives on HepG2 Cells: Accumulation of Reactive Oxygen Species and Induction of Cell Damage and Death

Effects of Common Food Additives on HepG2 Cells: Accumulation of Reactive Oxygen Species and Induction of Cell Damage and Death

Type VI Secretion System Accessory Protein TagAB-5 Promotes Burkholderia pseudomallei Pathogenicity in Human Microglia.

Central nervous system (CNS) melioidosis caused by Burkholderia pseudomallei is being increasingly reported. Because of the high mortality associated with CNS melioidosis, understanding the underlying mechanism of B. pseudomallei pathogenesis in the CNS needs to be intensively investigated to develop better therapeutic strategies against this deadly disease. The type VI secretion system (T6SS) is a multiprotein machine that uses a spring-like mechanism to inject effectors into target cells to benefit the infection process. In this study, the role of the T6SS accessory protein TagAB-5 in B. pseudomallei pathogenicity was examined using the human microglial cell line HCM3, a unique resident immune cell of the CNS acting as a primary mediator of inflammation. We constructed B. pseudomallei tagAB-5 mutant and complementary strains by the markerless allele replacement method. The effects of tagAB-5 deletion on the pathogenicity of B. pseudomallei were studied by bacterial infection assays of HCM3 cells. Compared with the wild type, the tagAB-5 mutant exhibited defective pathogenic abilities in intracellular replication, multinucleated giant cell formation, and induction of cell damage. Additionally, infection by the tagAB-5 mutant elicited a decreased production of interleukin 8 (IL-8) in HCM3, suggesting that efficient pathogenicity of B. pseudomallei is required for IL-8 production in microglia. However, no significant differences in virulence in the Galleria mellonella model were observed between the tagAB-5 mutant and the wild type. Taken together, this study indicated that microglia might be an important intracellular niche for B. pseudomallei, particularly in CNS infection, and TagAB-5 confers B. pseudomallei pathogenicity in these cells.

The Potential Role of Polyamines in Epilepsy and Epilepsy-Related Pathophysiological Changes.

Epilepsy is one of the most common neurological disorders and severely impacts the life quality of patients. Polyamines are ubiquitous, positively charged aliphatic amines that are present at a relatively high level and help regulate the maintenance of cell membrane excitability and neuronal physiological functions in the central nervous system. Studies have shown abnormalities in the synthesis and catabolism of polyamines in patients with epilepsy and in animal models of epilepsy. The polyamine system seems to involve in the pathophysiological processes of epilepsy via several mechanisms such as the regulation of ion permeability via interaction with ion channels, involvement in antioxidation as hydroperoxide scavengers, and the induction of cell damage via the production of toxic metabolites. In this review, we try to describe the possible associations between polyamines and epilepsy and speculate that the polyamine system is a potential target for the development of novel strategies for epilepsy treatment.

Neuroprotective Effects of Methyl Caffeate against Hydrogen Peroxide-Induced Cell Damage: Involvement of Caspase 3 and Cathepsin D Inhibition.

Finding effective neuroprotective strategies to combat various neurodegenerative disorders still remain a clinically unmet need. Methyl caffeate (MC), a naturally occurring ester of caffeic acid, possesses antioxidant and anti-inflammatory activities; however, its role in neuroprotection is less investigated. In order to better characterize neuroprotective properties of MC, we tested its effectiveness in various models of neuronal cell injury in human neuroblastoma SH-SY5Y cells and in mouse primary neuronal cell cultures. MC at micromolar concentrations attenuated neuronal cell damage induced by hydrogen peroxide (H2O2) in undifferentiated and neuronal differentiated SH-SY5Y cells as well as in primary cortical neurons. This effect was associated with inhibition of both caspase-3 and cathepsin D but without involvement of the PI3-K/Akt pathway. MC was neuroprotective when given before and during but not after the induction of cell damage by H2O2. Moreover, MC was protective against 6-OHDA-evoked neurotoxicity in neuronal differentiated SH-SY5Y cells via inhibition of necrotic and apoptotic processes. On the other hand, MC was ineffective in models of excitotoxicity (induced by glutamate or oxygen–glucose deprivation) and even moderately augmented cytotoxic effects of the classical apoptotic inducer, staurosporine. Finally, in undifferentiated neuroblastoma cells MC at higher concentrations (above 50 microM) induced cell death and when combined with the chemotherapeutic agent, doxorubicin, it increased the cell damaging effects of the latter compound. Thus, neuroprotective properties of MC appear to be limited to certain models of neurotoxicity and depend on its concentrations and time of administration.

Lipid Peroxidation Assay Using BODIPY-Phenylbutadiene Probes: A Methodological Overview.

The assessment of reactive oxygen species has increasing importance in biomedical sciences, due to their biological role in signaling pathways and induction of cell damage at low and high concentrations, respectively. Detection of lipid peroxidation with sensing probes such as some BODIPY dyes has now wide application in studies using fluorescent microplate readers, flow cytometry, and fluorescence microscopy. Two phenylbutadiene derivatives of BODIPY are commonly used as peroxidation probes, non-oxidized probes and oxidized products giving red and green fluorescence, respectively. Peculiar features of lipoperoxidation and BODIPY dye properties make this assessment a rather complex process, not exempt of doubts and troubles. Color changes and fluorescence fading that are not due to lipid peroxidation must be taken into account to avoid misleading results. As a characteristic feature of lipoperoxidation is the propagation of peroxyl radicals, pitfalls and advantages of a delayed detection by BODIPY probes should be considered.

The role of Candida albicans candidalysin ECE1 gene in oral carcinogenesis.

Oral squamous cell carcinoma is associated with many known risk factors including tobacco smoking, chronic alcoholism, poor oral hygiene, unhealthy dietary habits and microbial infection. Previous studies have highlighted Candida albicans host tissue infection as a risk factor in the initiation and progression of oral cancer. Calbicans invasion induces several cancerous hallmarks, such as activation of proto-oncogenes, induction of DNA damage and overexpression of inflammatory signalling pathways. However, the molecular mechanisms behind these responses remain unclear. A recently discovered fungal toxin peptide, candidalysin, has been reported as an essential molecule in epithelial damage and host recognition of Calbicans infection. Candidalysin has a clear role in inflammasome activation and induction of cell damage. Several inflammatory molecules such as IL-6, IL-17, NLRP3 and GM-CSF have been linked to carcinogenesis. Candidalysin is encoded by the ECE1 gene, which has been linked to virulence factors of Calbicans such as adhesion, biofilm formation and filamentation properties. This review discusses the recent epidemiological burden of oral cancer and highlights the significance of the ECE1 gene and the ECE1 protein breakdown product, candidalysin in oral malignancy. The immunological and molecular mechanisms behind oral malignancy induced by inflammation and the role of the toxic fungal peptide candidalysin in oral carcinogenesis are explored. With increasing evidence associating Calbicans with oral carcinoma, identifying the possible fungal pathogenicity factors including the role of candidalysin can assist in efforts to understand the link between Calbicans infection and carcinogenesis, and pave the way for research into therapeutic potentials.

Neuroprotective and Antiapoptotic Effects of N-acetylcystein and Crocus sativus Aqueous Extract on Arsenic-induced Neurotoxicity in SH-SY5Y Human Dopaminergic Neuroblastoma Cells

Abstract: Background: Parkinson’s disease is mainly specified by progressive and selective death of dopaminergic neurons. Crocus sativus L. (saffron) has been widely used to cure a diverse range of diseases in herbal medicine. Aim: The aim of the present study is to investigate the neuroprotective effects of saffron on arsenic-induced neurotoxicity, which was performed in human neuroblastoma SH-SY5Y cell line as an in vitro model of Parkinson’s disease and to confirm whether the neuroprotective effects of saffron on Parkinson’s disease are mainly due to their interactions with antioxidant systems. Moreover, as the antioxidant effect of N-acetylcysteine and its effectiveness as an antioxidant agent are proven, we compared saffron with NAC to control saffron extract. Material and Methods: The induction of cell damage was done by arsenic and the survival of the cells was measured using the MTT assay. In addition, the assessment of the generation of intracellular Reactive Oxygen Species (ROS) and mitochondrial membrane potential was done using fluorescence spectrophotometry method. Furthermore, immunoblotting analysis was performed to precisely determine the biomarkers level for apoptosis in the cells. Results: Our study indicated that arsenic had the ability to decrease cells survival rate, enhance the loss of mitochondrial membrane potential and increase the levels of intracellular ROS, c-Fos ratio and caspease-3. Pretreatment of cells with NAC (5 mM) and saffron aqueous extract (10mg/ml) significantly attenuated the mentioned effects in arsenic-treated cells. Conclusion: The outcome of the study has shown that the protective effects of NAC and saffron aqueous extract are produced by their antioxidant and antiapoptotic properties and their therapeutic potential is demonstrated in the treatment of Parkinson’s disease. Key words: Parkinson Disease, N-acetylcysteine, Saffron, Arsenic, SH-SY5Y cells.

Particulate Matter 2.5 Mediates Cutaneous Cellular Injury by Inducing Mitochondria-Associated Endoplasmic Reticulum Stress: Protective Effects of Ginsenoside Rb1.

The prevalence of fine particulate matter-induced harm to the human body is increasing daily. The aim of this study was to elucidate the mechanism by which particulate matter 2.5 (PM2.5) induces damage in human HaCaT keratinocytes and normal human dermal fibroblasts, and to evaluate the preventive capacity of the ginsenoside Rb1. PM2.5 induced oxidative stress by increasing the production of reactive oxygen species, leading to DNA damage, lipid peroxidation, and protein carbonylation; this effect was inhibited by ginsenoside Rb1. Through gene silencing of endoplasmic reticulum (ER) stress-related genes such as PERK, IRE1, ATF, and CHOP, and through the use of the ER stress inhibitor tauroursodeoxycholic acid (TUDCA), it was demonstrated that PM2.5-induced ER stress also causes apoptosis and ultimately leads to cell death; however, this phenomenon was reversed by ginsenoside Rb1. We also found that TUDCA partially restored the production of ATP that was inhibited by PM2.5, and its recovery ability was significantly higher than that of ginsenoside Rb1, indicating that the process of ER stress leading to cell damage may also occur via the mitochondrial pathway. We concluded that ER stress acts alone or via the mitochondrial pathway in the induction of cell damage by PM2.5, and that ginsenoside Rb1 blocks this process. Ginsenoside Rb1 shows potential for use in skin care products to protect the skin against damage by fine particles.

Assessment of the ecotoxicity of urban estuarine sediment using benthic and pelagic copepod bioassays.

Urban estuarine sediments are sinks to a range of contaminants of anthropogenic origin, and a key challenge is to characterize the risk of these compounds to receiving environments. In this study, the toxicity of urban estuarine sediments was tested using acute and chronic bioassays in the benthic harpacticoid Quinquelaophonte sp., and in the planktonic calanoid Gladioferens pectinatus, two New Zealand copepod species. The sediment samples from the estuary tributary sites significantly impacted reproduction in Quinquelaophonte sp. However, results from one of the estuary sites were not significantly different to those from the tributaries sites, suggesting that chemicals other than trace metals, polycyclic aromatic hydrocarbons and ammonia may be the causative stressors. Sediment elutriate samples had significant effects on reproductive endpoints in G. pectinatus, and on the induction of DNA damage in cells, as shown by the comet assay. The results indicate that sediment contamination at the Ahuriri Estuary has the potential to impact biological processes of benthic and pelagic organisms. The approach used provides a standardized methodology to assess the toxicity of estuarine sediments.

Perfluorooctanoic acid induces mitochondrial dysfunction in MC3T3-E1 osteoblast cells

ABSTRACTPerfluorooctanoic acid (PFOA), a stable organic perfluorinated compound, is an emerging persistent organic pollutant, found widely in human and wildlife populations. Recent evidence suggests that exposure to environmental toxicants can be associated with higher risks of osteoporosis and fractures. We studied the cellular toxicology of PFOA in MC3T3-E1osteoblast cells. To examine the effect of PFOA, we measured cell viability, reactive oxygen species (ROS), mitochondrial superoxide, and mitochondrial parameters including adenosine triphosphate (ATP) level, mitochondrial membrane potential (MMP), cardiolipin content, and cytochrome c release in MC3T3-E1 cells. Incubating MC3T3-E1 cells in different concentrations of PFOA for 48 h resulted in a concentration-dependent decrease in cell viability and significant inductions of ROS and mitochondrial superoxide. Moreover, PFOA induced MMP collapse, cardiolipin peroxidation, cytochrome c release, and decreased ATP levels, which in turn induced apoptosis or necrosis. When osteoblast differentiation markers were assessed, PFOA treatment caused a significant reduction in alkaline phosphatase activity, collagen synthesis, and mineralization in the cells. In summary, we found an ROS- and mitochondria-mediated pathway for the induction of cell damage by PFOA in MC3T3-E1 cells. Together, our results indicate that mitochondrial toxicity could be a plausible mechanism for the toxic effects of PFOA on osteoblast function.

Efficacy of combined therapy with paclitaxel and low-level ultrasound in human chronic myelogenous leukemia cell line K562

Background: Sonochemotherapy, which applies ultrasound in cancer chemotherapy, has been proven to be a promising therapeutic modality by some previous researches.Purpose: To investigate the interaction between an antineoplastic agent – paclitaxel (PTX) and low-level ultrasound in human chronic myelogenous leukemia cell line K562, their combined efficacy, and the potential mechanisms in sonochemotherapy.Methods: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) analysis and Guava Viacount assay were adopted to examine cell viability. Apoptosis was analyzed using Annexin V-PE/7-amino-actinomycin D staining. Changes in plasma membrane permeability were monitored by FD500-uptake and lactate dehydrogenase (LDH) release assays. Additionally, the ultrastructure changes were evaluated under scanning electron microscope (SEM).Results: When 5 ng/ml PTX was combined with sonication at Load Power (LP) = 2 W, the expected synergistic effects on cell viability loss (p < 0.05) and apoptosis enhancement could be significantly detected, the plasma membrane permeability showed the best response, and relatively serious cell damages were observed under SEM.Conclusion: The interaction between these two therapies depended on specific parameter settings, such as PTX dose and ultrasound intensity. Under synergistic conditions, ultrasound significantly potentiated the efficacies of PTX, including cytotoxicity, apoptosis and cell damage induction, which may be due to the enhanced membrane permeability and the increased intracellular PTX level.

Candida albicans cell wall glycosylation may be indirectly required for activation of epithelial cell proinflammatory responses.

Oral epithelial cells discriminate between the yeast and hyphal forms of Candida albicans via the mitogen-activated protein kinase (MAPK) signaling pathway. This occurs through phosphorylation of the MAPK phosphatase MKP1 and activation of the c-Fos transcription factor by the hyphal form. Given that fungal cell wall polysaccharides are critical in host recognition and immune activation in myeloid cells, we sought to determine whether β-glucan and N- or O-glycosylation was important in activating the MAPK/MKP1/c-Fos hypha-mediated response mechanism and proinflammatory cytokines in oral epithelial cells. Using a series of β-glucan and N- and O-mannan mutants, we found that N-mannosylation (via Δoch1 and Δpmr1 mutants) and O-mannosylation (via Δpmt1 and Δmnt1 Δmnt2 mutants), but not phosphomannan (via a Δmnn4 mutant) or β-1,2 mannosylation (via Δbmt1 to Δbmt6 mutants), were required for MKP1/c-Fos activation, proinflammatory cytokine production, and cell damage induction. However, the N- and O-mannan mutants showed reduced adhesion or lack of initial hypha formation at 2 h, resulting in little MKP1/c-Fos activation, or restricted hypha formation/pseudohyphal formation at 24 h, resulting in minimal proinflammatory cytokine production and cell damage. Further, the α-1,6-mannose backbone of the N-linked outer chain (corresponding to a Δmnn9 mutant) may be required for epithelial adhesion, while the α-1,2-mannose component of phospholipomannan (corresponding to a Δmit1 mutant) may contribute to epithelial cell damage. β-Glucan appeared to play no role in adhesion, epithelial activation, or cell damage. In summary, N- and O-mannosylation defects affect the ability of C. albicans to induce proinflammatory cytokines and damage in oral epithelial cells, but this may be due to indirect effects on fungal pathogenicity rather than mannose residues being direct activators of the MAPK/MKP1/c-Fos hypha-mediated immune response.

Induction of cell damage and change of miR-133b expression by paraquat in PC12 cells

To investigate the effect of paraquat on induction of cell damage and miR-133b expression in PC12 cells. Cytotoxicity of PC12 cells was measured by MTT assay, following the PC12 cells treatment with 50, 100, or 300 µmol/L paraquat. Cell apoptosis was examined by the method of Annexin V-FITC/PI in flow cytometry (FCM) and the relative level of miR-133b expression was measured by real time RT-PCR, following the PC12 cells treatment with 100 or 300 µmol/L paraquat. Survival rate of PC12 cells treated with 100 or 300 µmol/L paraquat was lower than that of the vehicle control group (P < 0.01, P < 0.05), in the dose dependent pattern. Apoptotic rate of PC12 cells treated with 100, 300 µmol/L paraquat was higher than that of the vehicle control group (P < 0.05). The relative level of miR-133b expression of PC12 cells treated with 300 µmol/L paraquat was higher than that of the vehicle control group (P < 0.05). Paraquat may cause cell damage and induce apoptosis in PC12 cells, and induce miR-133b expression.

Radiation-induced perturbation of cell-to-cell signalling and communication

The investigation of the bystander phenomena (i.e. the induction of damage in cells not directly traversed by radiation) is strictly related to the study of the mechanisms of intercellular communication and of the perturbative effects of radiation. A new possible way to try to solve the bystander puzzle is through a 'systems radiation biology' approach with the total integration of experimental and theoretical activities. In particular, this contribution will focus on: (1) 'ad hoc' experiments designed to quantify key parameters involved in intercellular signalling (focusing, as a pilot study, on release, decay and internalization of interleukine-6 molecules, their modulation by radiation, and possible differences between in vivo/in vitro behaviour); (2) the implementation and the development of two different modelling approaches: a stochastic model (based on a Monte Carlo code) that takes account of the local mechanisms of release and internalization of signalling molecules (e.g. cytokines) and an analytical model where signal molecules are treated as a population and their temporal behaviour is described by differential equations. This approach provided instruments to investigate the complex phenomena of signal transmission and the role of cell communication to guarantee (maintain) the robustness of the in vitro experimental systems against the effects of perturbations.

The importance of fine dust for the development of an environmentally induced dry eye

Abstract Purpose Environmental conditions promote dry eye by destruction of tear fluid and induction of cell damage. Fine dust is not only present in an urban polluted environment, but also in a cigarette fume or candle light dust loaded home environment. We wanted to determine, if fine dust affects the tear fluid components and conjunctival cells. Methods Human tear fluid from volunteers was obtained and incubated with fine dust suspensions. Possible tear protein changes were analysed by polyacrylamidegel‐electrophoresis (PAGE). Cultivated human conjunctival cells (CHANG‐cells) were incubated with fine dust suspensions as well as exposed to ultraviolet light (UV‐A). Cytomorphological changes and cell vitality were analysed via CASY1 Cell Counter and MTS‐assay. Results Fine dust suspensions destroy tear fluid proteins, particularly in combination with UV‐A‐light irradiation. Moreover, the incubation of human conjunctival cells with fine dust suspensions leads to a statistically significant decrease of cell vitality, depending on the fine dust concentration and incubation period. Additional UV‐A‐irradiation induces a further reduction of cell vitality. Conclusion Due to the alterations of human tear proteins and conjunctival cells caused by fine dust and exaggerated by UV‐A‐irradiation, fine dust can also be responsible for the development of an environmentally induced dry eye.

Green tea polyphenol (–)‐epigallocatechin‐3‐gallate induces neurorescue of long‐term serum‐deprived PC12 cells and promotes neurite outgrowth

Our previous studies have shown that the green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) prevents neuronal cell death caused by several neurotoxins. The present study sought to determine the neuroprotective effect of EGCG when it is administered after the induction of cell damage ('neurorescue'). In an attempt to imitate a progressive mode of death, PC12 cells were initially subjected to serum-starvation conditions for a period of 1 or 3 days before administration of EGCG (0.1-10 microM) for up to 3 days. In spite of the high percentage of cell death, single or repetitive administration of EGCG (1 microM) significantly attenuated cell death. The neurorescue effect of EGCG was abolished by pre-treatment with the protein kinase C inhibitor GF109203X (2.5 microM), suggesting the involvement of the protein kinase C pathway in neurorescue by the drug. This is consistent with the rapid (15 min) translocation of the protein kinase C alpha isoform to the cell membrane in response to EGCG. The correlative neurite outgrowth activity of EGCG on PC12 cells may also contribute to its neurorescue effect. The present findings suggest that EGCG may have a positive impact on aging and neurodegenerative diseases to retard or perhaps even reverse the accelerated rate of neuronal degeneration.

Effect of Thermal Treatment of Refractory Ceramic Fibres on the Induction of Cytotoxicity and Cell Transformation

Refractory ceramic fibres (RCFs) are amorphous fibres made up of various metal oxides (mainly Al2O3 and SiO2), used as high temperature insulation materials. We have examined the surface properties of three RCFs from the TIMA repository, RCF1, RCF3 and RCF4 (RCF1 heated at the expected working temperature), which showed different potentials for cytotoxicity and the induction of morphological transformation in Syrian hamster embryo cells, RCF4 being less active. The degree of surface hydrophilicity, evaluated by adsorption calorimetry, showed that RCF4 is less hydrophilic than RCF1, likely as a consequence of the prior thermal treatment. In order to investigate the effect of thermal treatment on the cellular response to RCFs we have heated (800°C for 24 h) the most active fibre (RCF3) in air until it was converted to a fully hydrophobic material. The cytotoxic (colony forming efficiency) and transforming potencies of heated and unheated RCF3, measured at concentrations between 1 and 16 µg/cm 2 of culture dish for 7 days, were then compared. Both cytotoxicity and potential to transform cells dramatically decreased when fibres were heated, indicating that hydrophobicity blunts the cellular response to RCF3. These results confirm that the state of the surface of RCFs modulates the biological response elicited and that a correlation exists between the degree of surface hydrophilicity and induction of cell damage and transformation. Thermal treatment, by lowering the surface affinity of RCFs for water, inhibits some cell–fibre interactions and decreases the extent of internalization of the fibres.

Ethanol-induced augmentation of annexin IV expression in rat C6 glioma and human A549 adenocarcinoma cells.

We previously reported that the amount of annexin IV significantly increased in the postmortem brains of alcoholics compared with controls. To investigate further whether ethanol directly affects cellular expression of annexins in a cell, we used cell lines and compared the amounts of annexins between ethanol-exposed and control cells. Two kinds of cells (rat glioma C6 cells and human adenocarcinoma A549 cells) were used in the present study. Western blot analysis was performed to quantify expressed amounts of annexins using anti-annexin I, IV, and V antibodies. The mitochondrial enzyme (dehydrogenase) and caspase 3 activities were measured to assess cell damage (apoptosis) by ethanol. Expressive augmentation of annexin IV was shown in both C6 and A549 cells after a 5-hr exposure to 200 mM of ethanol, whereas amounts of annexins I and V were not changed. Both the mitochondrial dehydrogenase and caspase 3 activities were altered under the same conditions in C6 cells, indicating the induction of cell damage (apoptosis), whereas both of these enzyme activities were unchanged in A549 cells under the same conditions. The amount of annexin IV seemed to increase before the induction of cell damage by ethanol. Annexin IV might be one of the specific markers for the effect of ethanol.

Ethanol‐Induced Augmentation of Annexin IV Expression in Rat C6 Glioma and Human A549 Adenocarcinoma Cells

Background We previously reported that the amount of annexin IV significantly increased in the postmortem brains of alcoholics compared with controls. To investigate further whether ethanol directly affects cellular expression of annexins in a cell, we used cell lines and compared the amounts of annexins between ethanol‐exposed and control cells.Methods Two kinds of cells (rat glioma C6 cells and human adenocarcinoma A549 cells) were used in the present study. Western blot analysis was performed to quantify expressed amounts of annexins using anti‐annexin I, IV, and V antibodies. The mitochondrial enzyme (dehydrogenase) and caspase 3 activities were measured to assess cell damage (apoptosis) by ethanol.Results Expressive augmentation of annexin IV was shown in both C6 and A549 cells after a 5‐hr exposure to 200 mM of ethanol, whereas amounts of annexins I and V were not changed. Both the mitochondrial dehydrogenase and caspase 3 activities were altered under the same conditions in C6 cells, indicating the induction of cell damage (apoptosis), whereas both of these enzyme activities were unchanged in A549 cells under the same conditions.Conclusions The amount of annexin IV seemed to increase before the induction of cell damage by ethanol. Annexin IV might be one of the specific markers for the effect of ethanol.