Toxic Effects Of Ethanol Research Articles

Effects of Red Ginseng Extract on the Epididymal Sperm Motility of Mice Exposed to Ethanol

The protective effects of red ginseng extract and ginseng wine against ethanol-induced male reproductive toxicity were evaluated in male mice using computer-assisted sperm analysis. Mice were divided into 4 groups of 10 and fed plain saline, 6 g/kg per d of ethanol in saline, red ginseng extract plus ethanol, or a fermented preparation of red ginseng extract daily for 5 weeks. We found that the average seminal vesicle weight was significantly lower in the ethanol-treated group compared to the control group, while those of the ginseng-treated groups tended to be higher than the ethanol-treated group. We found a significant decrease in sperm motility and progressiveness in mice treated with ethanol for 5 weeks, while administration of ethanol plus red ginseng extract appeared to minimize the negative effects of ethanol toxicity on male fertility. Serum testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) were insignificantly lower in the ethanol-treated group than in the control group.

Resveratrol Restores Nrf2 Level and Prevents Ethanol-Induced Toxic Effects in the Cerebellum of a Rodent Model of Fetal Alcohol Spectrum Disorders

In humans, ethanol exposure during pregnancy produces a wide range of abnormalities in infants collectively known as fetal alcohol spectrum disorders (FASD). Neuronal malformations in FASD manifest as postnatal behavioral and functional disturbances. The cerebellum is particularly sensitive to ethanol during development. In a rodent model of FASD, high doses of ethanol (blood ethanol concentration 80 mM) induces neuronal cell death in the cerebellum. However, information on potential agent(s) that may protect the cerebellum against the toxic effects of ethanol is lacking. Growing evidence suggests that a polyphenolic compound, resveratrol, has antioxidant and neuroprotective properties. Here we studied whether resveratrol (3,5,4'-trihydroxy-trans-stilbene), a phytoalexin found in red grapes and blueberries, protects the cerebellar granule neurons against ethanol-induced cell death. In the present study, we showed that administration of resveratrol (100 mg/kg) to postnatal day 7 rat pups prevents ethanol-induced apoptosis by scavenging reactive oxygen species in the external granule layer of the cerebellum and increases the survival of cerebellar granule cells. It restores ethanol-induced changes in the level of transcription factor nuclear factor-erythroid derived 2-like 2 (nfe2l2, also known as Nrf2) in the nucleus. This in turn retains the expression and activity of its downstream gene targets such as NADPH quinine oxidoreductase 1 and superoxide dismutase in cerebellum of ethanol-exposed pups. These studies indicate that resveratrol exhibits neuroprotective effects in cerebellum by acting at redox regulating proteins in a rodent model of FASD.

Deleterious Effects of Ethanol on Hematological Parameters and Fertility in Albino Rats

Objective: Hematological disorders including anaemia are prevalent in alcoholics. The study was an attempt to find out the toxic effects of ethanol on blood values and semen parameters of albino rats. Material & Methods: 15 male albino rats with body weight (bwt) of 190 – 220 gm were used for the 2-phase study. 25% ethanol was administered via oral cannula to a group of 5 male rats each at daily dose of 0.6ml/200gm bwt respec-tively for 3 days during phase I. Phase II was a recovery study involving 5 male rats exposed to dose regimen as in phase I, and sacrificed after 3-day withdrawal of treatment. The control group of 5 male rats was given sterile water ad-libitum. Each animal was weighed before sacrifice to obtain difference in bwt relative to its basal value. Blood samples were collected by cardio-puncture from the rats for hematology and serum testosterone at the end of each phase. Semen parameters were determined and compared with controls. Results: Ethanol caused significant reduction (P< 0.05) in the hematological profile as well as in the serum testoster-one and semen parameters of the animals. Discontinuation of the drug use however showed gradual recovery of the depressed indices of the semen, serum testosterone and blood parameters. Conclusion: The ethanol could induce reversible changes in hematological profiles and semen parameters of rats, and by extension man. Hence, the study supported the use of alcohol with caution especially in infertile men and those prone to anemic tendencies. Key Words: Albino rats; ethanol; semen parameters; hematology DOI: 10.3126/ajms.v1i2.3350Asian Journal of Medical Sciences 1 (2010) 37-40

Mechanisms of Ethanol-Induced Death of Cerebellar Granule Cells

Maternal ethanol exposure during pregnancy may cause fetal alcohol spectrum disorders (FASD). FASD is the leading cause of mental retardation. The most deleterious effect of fetal alcohol exposure is inducing neuroapoptosis in the developing brain. Ethanol-induced loss of neurons in the central nervous system underlies many of the behavioral deficits observed in FASD. The cerebellum is one of the brain areas that are most susceptible to ethanol during development. Ethanol exposure causes a loss of both cerebellar Purkinje cells and granule cells. This review focuses on the toxic effect of ethanol on cerebellar granule cells (CGC) and the underlying mechanisms. Both in vitro and in vivo studies indicate that ethanol induces apoptotic death of CGC. The vulnerability of CGC to ethanol-induced death diminishes over time as neurons mature. Several mechanisms for ethanol-induced apoptosis of CGC have been suggested. These include inhibition of N-methyl-D-aspartate receptors, interference with signaling by neurotrophic factors, induction of oxidative stress, modulation of retinoid acid signaling, disturbance of potassium channel currents, thiamine deficiency, and disruption of translational regulation. Cultures of CGC provide an excellent system to investigate cellular/molecular mechanisms of ethanol-induced neurodegeneration and to evaluate interventional strategies. This review will also discuss the approaches leading to neuroprotection against ethanol-induced neuroapoptosis.

Autophagy Reduces Acute Ethanol-Induced Hepatotoxicity and Steatosis in Mice

Alcohol abuse is a major cause of liver injury. The pathologic features of alcoholic liver disease develop over prolonged periods, yet the cellular defense mechanisms against the detrimental effects of alcohol are not well understood. We investigated whether macroautophagy, an evolutionarily conserved cellular mechanism that is commonly activated in response to stress, could protect liver cells from ethanol toxicity. Mice were acutely given ethanol by gavage. The effects of ethanol on primary hepatocytes and hepatic cell lines were also studied in vitro. Ethanol-induced macroautophagy in the livers of mice and cultured cells required ethanol metabolism, generation of reactive oxygen species, and inhibition of mammalian target of rapamycin signaling. Suppression of macroautophagy with pharmacologic agents or small interfering RNAs significantly increased hepatocyte apoptosis and liver injury; macroautophagy therefore protected cells from the toxic effects of ethanol. Macroautophagy induced by ethanol seemed to be selective for damaged mitochondria and accumulated lipid droplets, but not long-lived proteins, which could account for its protective effects. Increasing macroautophagy pharmacologically reduced hepatotoxicity and steatosis associated with acute ethanol exposure. Macroautophagy protects against ethanol-induced toxicity in livers of mice. Reagents that modify macroautophagy might be developed as therapeutics for patients with alcoholic liver disease.

Toxic effects of ethanol on bovine serum albumin

The toxic effects of ethanol on bovine serum albumin (BSA) were measured by resonance light scattering (RLS), fluorescence spectroscopy, ultraviolet spectrophotometry (UV), circular dichroism (CD), and transmission electron microscopy (TEM). The results indicated that ethanol had toxic effects on BSA, which led to protein denaturation and the effects increased with the ethanol dose. By means of RLS, BSA was found to aggregate in the presence of ethanol and particles smaller than 100 nm were observed from TEM. The fluorescence spectra showed that the intensity of the characteristic peak of BSA decreased and blue shifted, because of changes in the BSA skeleton structure, as well as alteration of the microenvironment of tryptophan (Trp) residues. The conformation changes of BSA were also shown by UV and CD spectrometry.

Herp mRNA expression in patients classified according to Lesch's typology

Chronic alcoholism is associated with hyperhomocysteinemia. Herp (homocysteine-induced endoplasmic reticulum [ER] protein) levels are elevated as a response to ER stress prior to mitochondrial dysfunction and cell death. The Lesch classification system has been applied in many studies and has been found useful. This study was undertaken to assess Herp mRNA expression in actively drinking patients with alcoholism who were classified according to Lesch's typology. Herp mRNA expression levels were measured by quantitative PCR in the blood of 76 male alcoholic patients. Patients were classified according to Lesch's typology (type I–IV). With respect to Lesch's typology, a significant difference in Herp mRNA expression regarding the four subtypes could be shown ( F[3,72] = 2.83, P = .044). In a logistic regression model (dependent variable Herp dichotomized by a median-split; adjusted for age and homocysteine levels) the subtype II differed statistically significant from the others (odds ratio, 5.75; 95% confidence interval, 2.07–15.98; P = .001). Type II alcoholic patients had a statistically significant higher expression of Herp mRNA due to upregulation of the expression of this neuroprotective cell non-chaperone by toxic effects of ethanol. These findings might explain why type II patients do not express severe withdrawal symptomatology (i.e., withdrawal seizures). These findings may be useful in the understanding and treatment considerations of different subtypes of alcohol dependence.

Integrative Basic Sciences: Change in Mental Status

This case discussion is part of the Integrating Basic Science Into Clinical Teaching Initiative. It examines the presentation of altered mental status and describes the underlying physiology, which explains the basic laboratory findings in an attempt to reach a diagnosis. This article describes a 13-year-old boy who presented to the emergency department with altered mental status after being found unconscious and alone in an abandoned building. He was unresponsive to painful and verbal stimuli, with otherwise normal findings on physical examination. Basic laboratory studies, including arterial blood gas, electrolytes, and serum osmolality, were obtained. The case discussion uses fundamentals of anatomy to build a focused differential diagnosis. The laboratory studies are interpreted using basic physiologic principles, including acid-base balance, anion gap, and osmolar gap, to determine the most likely cause of this patient's altered mental status. Subsequent investigation confirms a diagnosis of ethanol toxic effects. An understanding of electrolyte and acid-base physiology allows the clinician to use basic laboratory studies to build a focused differential diagnosis for altered mental status. This case discussion demonstrates how basic science principles of anatomy and physiology can be applied in clinical settings.

The Influence of the Nitric Oxide Synthase InhibitorL-NOARG on the Effects of Ethanol in Rats after Acute Ethanol Administration

Abstract: The aim of this work was to study the effects of the nitric oxide synthase inhibitor NG-nitro-L-arginine (L-NOARG) on the sedative and toxic effects of ethanol in rats. Ethanol at a dose of 3 g/kg, intraperitoneally induced sleep in rats (sleep time: 111.2±10.3 min.). Administration of the nitric oxide synthase inhibitor L-NOARG (20 and 40 mg/kg, intraperitoneally) 30 min. before ethanol significantly increased the duration of ethanol-induced sleep. L-NOARG at doses of 20 and 40 mg/kg reduced the exploratory activity of rats in the open-field test and significantly enhanced the sedative effect of ethanol in this test. It is possible that this effect is not caused by the interaction of ethanol with nitric oxide pathways but by synergistic CNS depression caused by ethanol and L-NOARG. L-NOARG (20 and 40 mg/kg) had no effect on ethanol concentrations in blood after acute ethanol administration (2 and 3 g/kg). Moreover, the combined administration of ethanol (2 g/kg) and L-NOARG (20 and 40 mg/kg) caused a decrease in the body weight of animals, observed for 14 days. Also, livers of these rats were studied for necrosis and connective tissue reaction. In histological studies L-NOARG at a dose of 40 mg/kg had no effect on hepatic necrosis caused by the acute administration of ethanol but strenghtened connective tissue reaction. L-NOARG is widely used in pharmacological studies, including those concerning the effects of ethanol. However, on the basis of our data the possibility of toxic interactions with ethanol should be considered.

Effect of Zinc on Hepatic Drug Metabolism under Ethanol Toxicity

The effects of zinc on drug-metabolizing enzymes in the liver were examined in male Wistar rats following ethanol intoxication. Rats were orally fed 3 mL of 30% ethanol daily for either two, four, or eight weeks and were orally administered zinc sulfate (ZnSO4.7H2O) at a dose level of 227 mg/L. Levels of reduced glutathione (GSH) and the activities of cytochrome P-450, cytochrome b5, NADPH cytochrome-C-reductase and glutathione-S-transferase (GST) were determined in liver after two, four, and eight weeks. Significant elevation was observed in the activities of the enzymes of the mixed function oxidase system in response to toxicity induced by ethanol at all the intervals. These effects of were ascribed to the enhanced activity of the microsomal ethanol oxidizing system and the associated increase in reactive oxygen species production. Zinc supplementation to these ethanol-intoxicated animals resulted in normalization of these elevated values significantly, but still they do not attain normal levels. Significant increase was observed in reduced glutathione content in animals after four and eight weeks of ethanol feeding, which appeared to be further elevated in combined zinc and ethanol treatment. Significant elevation in the activity of GST was illustrated on ethanol-fed animals at all the three treatment intervals. Furthermore, the activity of this enzyme was only moderately normalized following zinc treatment. This was accredited to the antioxidant potential of zinc, as well as its ability to induce metallothionein content, which provide protection against the toxic effects of ethanol. To conclude, zinc was able to normalize the effects of ethanol in the liver.

Impact of Fatty Liver Disease on Health Care Utilization and Costs in a General Population: A 5-Year Observation

Fatty liver disease is a common condition in the Western world. Fatty liver may progress to steatohepatitis and cirrhosis. It is not yet known whether fatty liver disease results in higher health care utilization and costs. We used data from the Study of Health in Pomerania (SHIP), Germany, to assess the relation of fatty liver disease to self-reported health care utilization and costs at baseline and 5 years. The SHIP is a general population cohort study of 4310 adults aged 20 to 79 years at baseline in Pomerania. Fatty liver disease was defined as the presence of a hyperechogenic pattern of the liver and elevated serum alanine aminotransferase (ALT) levels. In multivariable analyses, average annual overall health care costs at baseline and follow-up measurement were significantly higher for individuals with sonographic fatty liver and increased serum ALT levels. For example, controlling for comorbid conditions, subjects with sonographic fatty liver disease and increased serum ALT levels had 26% higher overall health care costs at 5-year follow-up. Analyses also suggest that diabetes and cardiovascular disease might mediate the relation of fatty liver disease and health care utilization and costs. Policies seeking to minimize costs associated with fatty liver disease might want to consider addressing behavioral risk factors of fatty liver disease.

Ethanol toxic effects on teeth development during pregnancy—Morphometrical evaluation

Tooth development involves sequential interactions between dental epithelial and mesenchymal cells. Our previous studies demonstrated that preameloblast-conditioned medium (PA-CM) induces the odontogenic differentiation of human dental pulp cells (hDPCs), and the novel protein Cpne7 in PA-CM was suggested as a candidate signaling molecule. In the present study, we investigated biological function and mechanisms of Cpne7 in regulation of odontoblast differentiation. Cpne7 was expressed in preameloblasts and secreted extracellularly during ameloblast differentiation. After secretion, Cpne7 protein was translocated to differentiating odontoblasts. In odontoblasts, Cpne7 promoted odontoblastic markers and the expression of Dspp in vitro. Cpne7 also induced odontoblast differentiation and promoted dentin/pulp-like tissue formation in hDPCs in vivo. Moreover, Cpne7 induced differentiation into odontoblasts of non-dental mesenchymal stem cells in vitro, and promoted formation of dentin-like tissues including the structure of dentinal tubules in vivo. Mechanistically, Cpne7 interacted with Nucleolin and modulated odontoblast differentiation via the control of Dspp expression. These results suggest Cpne7 is a diffusible signaling molecule that is secreted by preameloblasts, and regulates the differentiation of mesenchymal cells of dental or non-dental origin into odontoblasts.

Effects of Marjoram Volatile Oil and Grape Seed Extract on Ethanol Toxicity in Male Rats

Natural dietary antioxidants are extensively studied for their ability to protect cells from miscellaneous damages. Marjoram volatile oil (Origanum majorana L., Lamiaceae) and grape seed extract (Vitis vinifera L., Vitaceae) are potent antioxidants. Effects of administration of marjoram volatile oil or grape seed extract on oral administration of ethanol, simultaneously, daily for 10 weeks were studied through determining epididymal spermatozoal analysis, serum testosterone level, weight and histopathological examination of testis, liver and brain. Glutathione level and lipid peroxidation content as malondialdehyde in the testis, liver and brain were measured. The repeated intake of a great amount of ethanol (10 ml/kg body weight, 25% v/v) was followed by fertility disturbances with low sperm count, impaired sperm motility and decrease in serum testosterone level. Moreover, ethanol toxicity induced significant alterations in the histological structures of the testis, liver and brain. The results revealed a significant increase in lipid peroxidation and decrease in the level of glutathione in the testis, liver and brain in the ethanol-treated group. However, co-administration of the extracts of protective plants resulted in minimizing the hazard effects of ethanol toxicity on male fertility, liver and brain tissues. It may be concluded that marjoram volatile oil and grape seed extract are useful herbal remedies, especially for controlling oxidative damages.

Sleep and brain monoamine changes produced by acute and chronic acetaldehyde administration in rats

Acetaldehyde, the most toxic metabolite of ethanol, has been implicated in many toxic effects of ethanol. In the present study, we used rats to investigate the possible changes on the sleep–wake cycle and brain regional concentrations of noradrenaline and serotonin after intraperitoneal administration of several doses of acetaldehyde. Results showed that acetaldehyde significantly decreases the time spent in rapid eye movements sleep and wakefulness and increases the time spent in slow-wave sleep. The neurochemical analysis showed that acetaldehyde significantly increases the 5-hydroxyindolacetic acid content and 5-hydroxyindolacetic acid/serotonin ratio at the bulb and pons. These results suggest that acetaldehyde modifies the metabolism of serotonin which has been implicated in the onset and sustaining of the sleep episodes occurring along the sleep–wake cycle.

Alcoholic dementia: myth or reality?

Chronic alcohol abuse and/or dependence may result in cognitive decline, ranging from isolated amnesia and/or mild cognitive impairment to full-blown dementia. The underlying mechanisms include deficiency of nutritional factors (such as B-complex vitamins) resulting in Wernicke-Koraskoff's syndrome, and/or pellagrous encephalopathy, liver failure, Marchiafava-Bignami disease and cerebrovascular disease or combinations of the above. However, it has been suggested that progressive cognitive impairment can occur in the absence of the above-established syndromes, and has been attributed to the direct toxic effect of ethanol on the brain. Basic and clinical research has been shown that alcohol may be directly toxic to nerve cells via interplay of oxidative stress, excitotoxicity, mitochondrial damage and apoptosis.

Effect of ethanol on human osteosarcoma cell proliferatation, differentiation and mineralization

The habitual consumption of even moderate quantities of alcoholic beverages is clearly associated with reduced bone mass, increased prevalence of skeletal fracture and also it is the major risk factor for the development of secondary osteoporosis. The present in vitro study was designed to determine the dose response effects of ethanol on osteoblast-like human osteosarcoma cells (SaOS-2) proliferation, differentiation, mineralization and cyto-toxicity. SaOS-2 cells were plated in 48 and 6 well culture plates and exposed to different concentrations of ethanol (1, 10, 100, 200 and 300 mM) for 24, 48 and 72 h. At the end of incubation, proliferation of cells was studied using crystal violet Bioassay. The cell lysate was utilized to determine ALP activity and conditioned media were used to measure LDH activity. Histochemical localization of ALP and mineralized nodules were studied from cells treated with ethanol (10 and 100 mM) for 21 days. At higher doses, there was a significant reduction in cell number, whereas at lower doses there were variable effects. In 24 h treatment, the higher doses showed a significant increase in ALP activity, whereas 48 and 72 h treatments showed an opposite trend. Ethanol treatment caused a dose- and time-dependent increase in LDH activity. Ethanol treatment altered the quality of mineralization at 10 mM dose whereas completely inhibited mineralization at 100 mM dose, despite the presence of serum. In conclusion, the toxic effect of ethanol is reflected on cell proliferation, differentiation and mineralization even at low doses and at extended treatment duration.

Atomic force microscopic study of the effects of ethanol on yeast cell surface morphology

The detrimental effects of ethanol toxicity on the cell surface morphology of Saccharomyces cerevisiae (strain NCYC 1681) and Schizosaccharomyces pombe (strain DVPB 1354) were investigated using an atomic force microscope (AFM). In combination with culture viability and mean cell volume measurements AFM studies allowed us to relate the cell surface morphological changes, observed on nanometer lateral resolution, with the cellular stress physiology. Exposing yeasts to increasing stressful concentrations of ethanol led to decreased cell viabilities and mean cell volumes. Together with the roughness and bearing volume analyses of the AFM images, the results provided novel insight into the relative ethanol tolerance of S. cerevisiae and Sc. pombe.

Oxidation of ethanol to acetaldehyde and free radicals by rat testicular microsomes

A large number of epidemiological studies evidencing that excessive alcohol consumption is associated with impaired testosterone production and testicular atrophy are available in the literature. One hypothesis to explain the deleterious action of alcohol involves the in situ biotransformation to acetaldehyde, but it strongly suggests the need to learn more about the enzymatic processes governing alcohol metabolism to acetaldehyde in different cellular fractions since limited information is available in the literature. In this article we report studies on the metabolic conversion of alcohol to acetaldehyde and to 1-hydroxyethyl radicals in rat testicular microsomal fractions. The oxidation of ethanol to acetaldehyde in rat testes microsomal fraction was mostly of enzymatic nature and strongly dependent on the presence of NADPH and oxygen. Several compounds were able to significantly decrease the production of acetaldehyde: SKF 525A; diethyldithiocarbamate; esculetin; gossypol; curcumin; quercetin; dapsone; and diphenyleneiodonium. Microsomal preparations in the presence of NADPH were also able to produce both hydroxyl and 1-hydroxyethyl free radicals. Their generation was modulated by the presence of diphenyleneiodonium, gossypol, and deferoxamine. Results show that rat microsomal fractions are able to metabolize alcohol to deleterious chemicals, such as acetaldehyde and free radicals, that may be involved in ethanol toxic effects. Enzymes involved could include CYP2E1, P450 reductase, and other enzymes having lipoxygenase- /peroxidase-like behavior.

Induction of NO-synthase and acetaldehyde dehydrogenase in neurons of human cerebellar cortex during chronic alcohol intoxication.

Induction of NO-synthase and acetaldehyde dehydrogenase in Purkinje cells, basket-like neurons, and microvascular endothelium of human cerebellar cortex was detected in patients with chronic alcohol intoxication. It was hypothesized that the neuromodulating effect of NO is associated with mechanisms protecting neurons from toxic effects of ethanol and acetaldehyde.

Studies on the Wine Spoilage Capacity ofBrettanomyces/Dekkeraspp

The presence of <i>Brettanomyces/Dekkera</i> in wine during barrel aging is often associated with detrimental organoleptic effects. The mechanisms underlying the capacity of these yeast species to grow and survive in wine with high ethanol levels and low sugar supply were investigated. Ethanol was used by <i>Brettanomyces bruxellensis</i> ISA 1791 and <i>Dekkera anomala</i> IGC 5153 as the sole carbon and energy source, the growth of the yeasts being dependent on the concentration of alcohol in the culture media. When specific growth rates of both yeasts were plotted against ethanol concentration, at high substrate levels there was a decline in the specific growth rate rather than an asymptotic approach to µ_max according to the Monod-based Bungay equation. Moreover, these yeasts exhibited greater capacity to grow at high ethanol concentrations than <i>Saccharomyces cerevisiae</i> IGC 4072. When glucose was used as the sole carbon and energy source, the growth of <i>B. bruxellensis</i> showed lower sensitivity to ethanol toxic effects than <i>S. cerevisiae</i>. In transport assays carried out with <i>B. bruxellensis</i> grown with glucose as the carbon source, the yeast expressed activity for two transport systems for the monosaccharide: facilitated diffusion, specific for glucose and fructose, and H⁺-dependent transport, specific for glucose and galactose and subject to glucose repression. The activity of both transport systems was inhibited noncompetitively by ethanol according to exponential inhibition kinetics, but 12% alcohol reduced sugar transport only by 60%. Findings help explain the ability of <i>Brettanomyces/Dekkera</i> spp. to grow and survive under the severe environmental conditions of wine.