PARP inhibition in vivo blocks alcohol-induced brain neurodegeneration and neuroinflammatory cytosolic phospholipase A2 elevations.

Chronic alcoholism promotes brain damage that impairs memory and cognition. High binge alcohol levels in adult rats also cause substantial neurodamage to memory-linked regions, notably, the hippocampus (HC) and entorhinal cortex (ECX). Concurrent with neurodegeneration, alcohol elevates poly (ADP-ribose) polymerase-1 (PARP-1) and cytosolic phospholipase A2 (cPLA2) levels. PARP-1 triggers necrosis when excessively activated, while cPLA2 liberates neuroinflammatory ω-6 arachidonic acid. Inhibitors of PARP exert in vitro neuroprotection while suppressing cPLA2 elevations in alcohol-treated HC-ECX slice cultures. Here, we examined in vivo neuroprotection and cPLA2 suppression by the PARP inhibitor, veliparib, in a recognized adult rat model of alcohol-binging. Adult male rats received Vanilla Ensure containing alcohol (ethanol, 7.1 ±â€¯0.3 g/kg/day), or control (dextrose) ±â€¯veliparib (25 mg/kg/day), by gavage 3x daily for 4 days. Rats were sacrificed on the morning after the final binge. HC and ECX neurodegeneration was assessed in fixed sections by Fluoro-Jade B (FJB) staining. Dorsal HC, ventral HC, and ECX cPLA2 levels were quantified by immunoblotting. Like other studies using this model, alcohol binges elevated FJB staining in the HC (dentate gyrus) and ECX, indicating neurodegeneration. Veliparib co-treatment significantly reduced dentate gyrus and ECX neurodegeneration by 79% and 66%, respectively. Alcohol binges increased cPLA2 in the ventral HC by 34% and ECX by 72%, which veliparib co-treatment largely prevented. Dorsal HC cPLA2 levels remained unaffected by alcohol binges, consistent with negligible FJB staining in this brain region. These in vivo results support an emerging key role for PARP in binge alcohol-induced neurodegeneration and cPLA2-related neuroinflammation.

Chronic Alcohol Exposure Induced Neuroapoptosis: Diminishing Effect of Ethyl Acetate Fraction from Aralia elata.

An ethyl acetate fraction from Aralia elata (AEEF) was investigated to confirm its neuronal cell protective effect on ethanol-induced cytotoxicity in MC-IXC cells and its ameliorating effect on neurodegeneration in chronic alcohol-induced mice. The neuroprotective effect was examined by methylthiazolyldiphenyl-tetrazolium bromide (MTT) and 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA) assays. As a result, AEEF reduced alcohol-induced cytotoxicity and oxidative stress. To evaluate the improvement of learning, memory ability, and spatial cognition, Y-maze, passive avoidance, and Morris water maze tests were conducted. The AEEF groups showed an alleviation of the decrease in cognitive function in alcohol-treated mice. Then, malondialdehyde (MDA) levels and the superoxide dismutase (SOD) content were measured to evaluate the antioxidant effect of AEEF in the brain tissue. Treatment with AEEF showed a considerable ameliorating effect on biomarkers such as SOD and MDA content in alcohol-induced mice. To assess the cerebral cholinergic system involved in neuronal signaling, acetylcholinesterase (AChE) activity and acetylcholine (ACh) content were measured. The AEEF groups showed increased ACh levels and decreased AChE activities. In addition, AEEF prevented alcohol-induced neuronal apoptosis via improvement of mitochondrial activity, including reactive oxygen species levels, mitochondrial membrane potential, and adenosine triphosphate content. AEEF inhibited apoptotic signals by regulating phosphorylated c-Jun N-terminal kinases (p-JNK), phosphorylated protein kinase B (p-Akt), Bcl-2-associated X protein (BAX), and phosphorylated Tau (p-Tau). Finally, the bioactive compounds of AEEF were identified as caffeoylquinic acid (CQA), 3,5-dicaffeoylquinic acid (3,5-diCQA), and chikusetsusaponin IVa using the UPLC-Q-TOF-MS system.

Propofol for Treatment of Refractory Alcohol Withdrawal Syndrome: A Review of the Literature.

The authors evaluated all available evidence on the use of propofol as an adjuvant for the treatment of resistant alcohol withdrawal syndrome (AWS) in comparison to other therapies. A comprehensive PubMed search (1966-December 2015) was conducted using the search terms propofol, alcohol withdrawal, and drug therapy. Articles were cross-referenced for other citations. Clinical studies, case series, and case reports published in the English language assessing the use of propofol in adult patients for treatment of AWS were reviewed for inclusion. Propofol is a sedative-hypnotic that exerts its actions through agonism of GABAA receptors at a different binding site than benzodiazepines and reduces glutamatergic activity through N-methyl-d-aspartase (NMDA) receptor blockade. Dosages from 5 to 100 µg/kg/minute reduced AWS symptoms with frequent development of hypotension and requirement for mechanical ventilation. Patients on propofol often experienced longer durations of mechanical ventilation and length of stay, which may be attributed to more-resistant cases of AWS. When propofol was compared with dexmedetomidine as adjuncts in AWS, both agents showed similar benzodiazepine- and haloperidol-sparing effects. Dexmedetomidine was associated with more numerical rates of bradycardia, while propofol was associated with more numerical instances of hypotension. Dexmedetomidine was used more frequently in nonintubated patients. The available data assessing the utility of propofol for AWS exhibited significant heterogeneity. Propofol may be useful in a specific population of patients with AWS, limited to those who are not clinically responding to first-line therapy with benzodiazepines. Specifically, propofol should be considered in patients who are refractory to or not candidates for other adjuvant therapies, patients already requiring mechanical ventilation, or those with seizure activity or refractory delirium tremens. In severe, refractory AWS, adjuvant therapy with propofol may be considered but requires further research to recommend its use either preferentially or as monotherapy.

Protective Effects of Tetramethylpyrazine on Cerebrovascular Regulations in Rats with Chronic Alcoholic Encephalopathy.

Recent studies showed that pathology of alcoholic encephalopathy was associated with cerebral vascular damage. TMP (tetramethyl- pyrazine) is widely used in the treatment of cerebrovascular diseases, however, it has not been reported whether TMP can relieve alcohol-induced cerebral vascular damages. The study was performed to investigate the learning and memory, cerebrovascular pathological changes and the expressions of vascular endothelial growth factor (VEGF) and serum levelsofendothelin-1 (ET-1) in the rat model of chronic alcoholic encephalopathy, and explore the effects of TMP intervention on alcoholic encephalopathy. In the present study, the rat model of chronic alcoholic encephalopathy was established by the gavage administration of alcohol; the learning and memory ability was tested by Morris water maze; the expression of VEGF was measured by RT-PCR and Western blot; and the serum levels of ET-1 was measured by radioimmunoassay. We found that alcohol intoxication impaired learning and memory, induced VEGF overexpression and increased ET 1 concentrations. TMP intervention improved learning abilities, increased the VEGF expression and reduced ET-1 level. These results indicate that TMP exhibits therapeutic effects on chronic alcoholic encephalopathy.

An alternative for rapid administration of medication and fluids in the emergency setting using a novel device.

Routes of administration for medications and fluids in the acute care setting have primarily focused on oral, intravenous, or intraosseous routes, but, in many patients, none of these routes is optimal. A novel device (Macy Catheter; Hospi Corp) that offers an easy route for administration of medications or fluids via rectal mucosal absorption (proctoclysis) has recently become available in the palliative care market; we describe here the first known uses of this device in the emergency setting. Three patients presenting to the hospital with conditions limiting more typical routes of medication or fluid administration were treated with this new device; patients were administered water for hydration, lorazepam for treatment of alcohol withdrawal, ondansetron for nausea, acetaminophen for fever, aspirin for antiplatelet effect, and methimazole for hyperthyroidism. Placement of the device was straightforward, absorption of administered medications (judged by immediacy of effects, where observable) was rapid, and use of the device was well tolerated by patients, suggesting that this device may be an appealing alternative route to medication and fluid administration for a variety of indications in acute and critical care settings.

Impact of thiamine supplementation in the reversal of ethanol induced toxicity in rats.

One of the molecular mechanisms of alcohol induced toxicities is mediated by oxidative stress. Hence our studies were focused on the effect of thiamine (antioxidant) in the reversal of alcohol induced toxicity and comparison of the reversal with abstinence. Administration of ethanol at a dose of 4 g/kg body wt/day for 90 days to Sprague Dawley rats manifested chronic alcohol induced toxicity evidenced by decreased body weight, an increase in liver-body weight ratio, increase in activities of serum and liver aspartate transaminase (AST), alanine transaminase (ALT), gamma-glutamyl transpeptidase (GGT); decrease in the activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase in the liver and brain. The levels of inflammatory markers, fibrosis markers and DNA fragmentation were also elevated in the serum, liver and brain. After ethanol administration for 90 days, the reversal of the alcohol induced toxicity was studied by supplementing thiamine at a dose of 25 mg/100 g body wt/day. Duration of the reversal study was 30 days. The activities of AST, ALT, GGT, scavenging enzymes as well as markers of inflammation and fibrosis in serum, liver and brain were reversed to a certain extent by thiamine. Changes in neurotransmitter levels in brain were also reversed by thiamine supplementation. DNA damage was decreased and DNA content increased in thiamine supplemented group compared to abstinence group showing a faster regeneration. In short, histopathological and biochemical evaluations indicate that thiamine supplemented abstinent rats made a faster recovery of hepatic and neuronal damage than in the abstinence group.

[Features of psychopharmacotherapeutic correction of alcohol dependence in the elderly].

The article is devoted to the actual in modern medicine problem as the study of the prevalence of alcohol dependence and its psyhofarmacological correction in the elderly. It is shown that elderly and old age as a result of reduction of the reserve capacity of the organism for clinical pathology becomes addictive specific psychopathological features that affect the course of disease and maintenance of preventive treatment. On the basis of empirical evidence the authors prove that at the border severity of alcohol withdrawal syndrome the drug "Cytoflavin" has a fairly pronounced psyhofarmacological activity for older people with alcohol dependence.

Phenobarbital for acute alcohol withdrawal: a prospective randomized double-blind placebo-controlled study.

BACKGROUND: Acute alcohol withdrawal syndrome (AAWS) is encountered in patients presenting acutely to the Emergency Department (ED) and often requires pharmacologic management. OBJECTIVE: We investigated whether a single dose of intravenous (i.v.) phenobarbital combined with a standardized lorazepam-based alcohol withdrawal protocol decreases intensive care unit (ICU) admission in ED patients with acute alcohol withdrawal. METHODS: This was a prospective, randomized, double-blind, placebo-controlled study. Patients were randomized to receive either a single dose of i.v. phenobarbital (10 mg/kg in 100 mL normal saline) or placebo (100 mL normal saline). All patients were placed on the institutional symptom-guided lorazepam-based alcohol withdrawal protocol. The primary outcome was initial level of hospital admission (ICU vs. telemetry vs. floor ward). RESULTS: There were 198 patients enrolled in the study, and 102 met inclusion criteria for analysis. Fifty-one patients received phenobarbital and 51 received placebo. Baseline characteristics and severity were similar in both groups. Patients that received phenobarbital had fewer ICU admissions (8% vs. 25%, 95% confidence interval 4-32). There were no differences in adverse events. CONCLUSIONS: A single dose of i.v. phenobarbital combined with a symptom-guided lorazepam-based alcohol withdrawal protocol resulted in decreased ICU admission and did not cause increased adverse outcomes.

Estrogen blocks the protective action of melatonin in a behavioral model of ethanol-induced hangover in mice.

Melatonin has antioxidant and neuroprotective properties in human beings and experimental models, as well as 'anti-estrogenic' effects. Ethanol (EtOH) affects various behavioral parameters during a period known as ethanol-induced hangover. Our study evaluated the neuroprotective effect of melatonin on motor performance during ethanol hangover in male and female Swiss mice. The females were subjected to specific hormonal states: ovariectomized (OVX) and OVX estrogenized (OVX-E(2)). Mice received melatonin (25 µg/ml) or vehicle in their drinking water for seven days and were given intraperitoneal (i.p.) injections of EtOH (3.8 g/kg) or saline on the morning of the eighth day. Motor performance was evaluated by the tightrope test 6h after EtOH exposure (hangover onset). During ethanol hangover, males exhibited lower motor performance than controls (p<0.01) but pretreatment with melatonin significantly improved performance during hangover (p<0.05). In females, melatonin treatment before ethanol-induced hangover led to a better motor performance in OVX compared with intact females (p<0.01) and a lower performance in OVX-E(2) compared with not-estrogenized OVX (p<0.05). Consequently, estrogen reversed the motor performance enhancement afforded by melatonin. We conclude that estrogen interferes with the protective action of melatonin on motor performance during ethanol hangover.

Dihydromyricetin as a novel anti-alcohol intoxication medication.

Alcohol use disorders (AUDs) constitute the most common form of substance abuse. The development of AUDs involves repeated alcohol use leading to tolerance, alcohol withdrawal syndrome, and physical and psychological dependence, with loss of ability to control excessive drinking. Currently there is no effective therapeutic agent for AUDs without major side effects. Dihydromyricetin (DHM; 1 mg/kg, i.p. injection), a flavonoid component of herbal medicines, counteracted acute alcohol (EtOH) intoxication, and also withdrawal signs in rats including tolerance, increased anxiety, and seizure susceptibility; DHM greatly reduced EtOH consumption in an intermittent voluntary EtOH intake paradigm in rats. GABA(A) receptors (GABA(A)Rs) are major targets of acute and chronic EtOH actions on the brain. At the cellular levels, DHM (1 µM) antagonized both acute EtOH-induced potentiation of GABA(A)Rs and EtOH exposure/withdrawal-induced GABA(A)R plasticity, including alterations in responsiveness of extrasynaptic and postsynaptic GABA(A)Rs to acute EtOH and, most importantly, increases in GABA(A)R α4 subunit expression in hippocampus and cultured neurons. DHM anti-alcohol effects on both behavior and CNS neurons were antagonized by flumazenil (10 mg/kg in vivo; 10 µM in vitro), the benzodiazepine (BZ) antagonist. DHM competitively inhibited BZ-site [(3)H]flunitrazepam binding (IC(50), 4.36 µM), suggesting DHM interaction with EtOH involves the BZ sites on GABA(A)Rs. In summary, we determined DHM anti-alcoholic effects on animal models and determined a major molecular target and cellular mechanism of DHM for counteracting alcohol intoxication and dependence. We demonstrated pharmacological properties of DHM consistent with those expected to underlie successful medical treatment of AUDs; therefore DHM is a therapeutic candidate.

Heart rate turbulence during acute alcohol withdrawal syndrome.

BACKGROUND: Alcohol withdrawal syndrome is associated with an increased incidence of cardiac arrhythmias and sudden cardiac death. Heart rate turbulence (HRT) parameters were applied during withdrawal to estimate cardiac regulation during treatment with clomethiazole. METHODS: Twenty-two patients suffering from alcohol withdrawal syndrome were included in the study. Heart rate regulation was obtained by means of Holter ECG analyzing time intervals before medication, and 2 and 6h after medication. Slope and onset of HRT were calculated in addition to heart rate variability (HRV) parameters. Furthermore, we calculated the slope and the onset of ectopic beat-like events. RESULTS: Heart rate variability parameters indicated a minor reduction of vagal modulation during withdrawal syndrome. Especially, the fractal scaling exponent BBI alpha1 (4-16) indicated the autonomic shift. In contrast to HRV parameters, no significant changes were observed in the HRT parameters. Significant correlations were observed between severity of withdrawal, as assessed by the AWS scale, and the fractal scaling exponent BBI alpha2 (16-64), and the onset and the slope of HRT of ectopic beat-like activity. CONCLUSION: Increased sympathetic modulation during withdrawal and clomethiazole treatment is not associated with changes of heart rate turbulence parameters predictive of cardiac death after myocardial infarction.

Mifepristone in the central nucleus of the amygdala reduces yohimbine stress-induced reinstatement of ethanol-seeking.

Chronic ethanol exposure leads to dysregulation of the hypothalamic-pituitary-adrenal axis, leading to changes in glucocorticoid release and function that have been proposed to maintain pathological alcohol consumption and increase vulnerability to relapse during abstinence. The objective of this study was to determine whether mifepristone, a glucocorticoid receptor antagonist, plays a role in ethanol self-administration and reinstatement. Male, Long-Evans rats were trained to self-administer either ethanol or sucrose in daily 30 min operant self-administration sessions using a fixed ratio 3 schedule of reinforcement. Following establishment of stable baseline responding, we examined the effects of mifepristone on maintained responding and yohimbine-induced increases in responding for ethanol and sucrose. Lever responding was extinguished in separate groups of rats and animals were tested for yohimbine-induced reinstatement and corticosterone release. We also investigated the effects of local mifepristone infusions into the central amygdala (CeA) on yohimbine-induced reinstatement of ethanol- and sucrose-seeking. In addition, we infused mifepristone into the basolateral amygdala (BLA) in ethanol-seeking animals as an anatomical control. We show that both systemic and intra-CeA (but not BLA) mifepristone administration suppressed yohimbine-induced reinstatement of ethanol-seeking, while only systemic injections attenuated sucrose-seeking. In contrast, baseline consumption, yohimbine-induced increases in responding, and circulating CORT levels were unaffected. The data indicate that the CeA plays an important role in the effects of mifepristone on yohimbine-induced reinstatement of ethanol-seeking. Mifepristone may be a valuable pharmacotherapeutic strategy for preventing relapse to alcohol use disorders and, as it is FDA approved, may be a candidate for clinical trials in the near future.

Ameliorative effect of BDNF on prenatal ethanol and stress exposure-induced behavioral disorders.

Brain-derived neurotrophic factor (BDNF) plays critical role in neuronal development, function, survival and plasticity of mature neurons. The present experiments investigated whether BDNF ameliorates the damaging effect of prenatal ethanol and stress exposure on behavior in offspring. Prenatal exposure of ethanol and stress combined during gestation inverted sexual partner preference of male offspring, increased social contacts with juvenile male mouse and stereotypic burying activity in the marble-burying test suggesting predisposition to homosexuality and to obsessive-compulsive disorder. Centrally administered BDNF (300ng i.c.v.) restored sexual female preference of male adult offspring and decreased marble-burying activity. Ameliorative effect was shown in 7-10 days after BDNF administration. The results provide the first evidence that BDNF improves epigenetic impairment of behavior and may have profound implications in the treatment of neurologic disorders induced by early environmental challenges.

Endothelial dysfunction during acute alcohol withdrawal syndrome.

BACKGROUND: Endothelial dysfunction (EF) is a central phenomenon in a variety of conditions associated with increased cardiovascular morbidity. Here, we investigated EF during acute alcohol withdrawal syndrome before and 24h after medication. We aimed to analyze microcirculation, applying the post-occlusive reactive hyperemia (PORH) test and spectral analysis of skin vasomotion as markers of EF. Additionally, we explored whether segmentation of spectral analysis data may disclose more detailed information on dynamic blood flow behavior. METHODS: We investigated 30 unmedicated patients during acute alcohol withdrawal syndrome and matched controls. Patients were reinvestigated after 24h when half of them had been treated with clomethiazole. Capillary blood flow was assessed on the right forearm after compression of the brachial artery. Parameters of PORH such as time to peak (TP), slope and PORH indices were calculated. Spectral analysis was performed in order to study five different frequency bands. Withdrawal symptoms were quantified by means of the alcohol withdrawal scale (AW scale). RESULTS: We observed a blunted hyperemic response in patients after occlusion of the brachial artery indicated by significantly increased TP and decreased PORH indices. In contrast, vasomotion as investigated by spectral analysis was not altered. Segmentation analysis revealed some alterations in the cardiac band at rest, and indicated differences between treated and untreated patients after 24h. CONCLUSION: Our results suggest peripheral endothelial dysfunction in patients during acute alcohol withdrawal. No major influence of treatment was observed. Future studies need to address the relation of EF to cardiac morbidity during alcohol withdrawal.

Cyanidin-3-glucoside ameliorates ethanol neurotoxicity in the developing brain.

Ethanol exposure induces neurodegeneration in the developing central nervous system (CNS). Fetal alcohol spectrum disorders (FASD) are caused by ethanol exposure during pregnancy and are the most common nonhereditary cause of mental retardation. It is important to identify agents that provide neuroprotection against ethanol neurotoxicity. Multiple mechanisms have been proposed for ethanol-induced neurodegeneration, and oxidative stress is one of the most important mechanisms. Recent evidence indicates that glycogen synthase kinase 3ß (GSK3ß) is a potential mediator of ethanol-mediated neuronal death. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is a potent natural antioxidant. Our previous study suggested that C3G inhibited GSK3ß activity in neurons. Using a third trimester equivalent mouse model of ethanol exposure, we tested the hypothesis that C3G can ameliorate ethanol-induced neuronal death in the developing brain. Intraperitoneal injection of C3G reduced ethanol-meditated caspase-3 activation, neurodegeneration, and microglial activation in the cerebral cortex of 7-day-old mice. C3G blocked ethanol-mediated GSK3ß activation by inducing phosphorylation at serine 9 while reducing the phosphorylation at tyrosine 216. C3G also inhibited ethanol-stimulated expression of malondialdehyde (MDA) and p47phox, indicating that C3G alleviated ethanol-induced oxidative stress. These results provide important insight into the therapeutic potential of C3G.

Pharmacologically induced alcohol craving in treatment seeking alcoholics correlates with alcoholism severity, but is insensitive to acamprosate.

Modulation of alcohol craving induced by challenge stimuli may predict the efficacy of new pharmacotherapies for alcoholism. We evaluated two pharmacological challenges, the α(2)-adrenergic antagonist yohimbine, which reinstates alcohol seeking in rats, and the serotonergic compound meta-chlorophenylpiperazine (mCPP), previously reported to increase alcohol craving in alcoholics. To assess the predictive validity of this approach, the approved alcoholism medication acamprosate was evaluated for its ability to modulate challenge-induced cravings. A total of 35 treatment seeking alcohol dependent inpatients in early abstinence were randomized to placebo or acamprosate (2997 mg daily). Following two weeks of medication, subjects underwent three challenge sessions with yohimbine, mCPP or saline infusion under double blind conditions, carried out in counterbalanced order, and separated by at least 5 days. Ratings of cravings and anxiety, as well as biochemical measures were obtained. In all, 25 subjects completed all three sessions and were included in the analysis. Cravings were modestly, but significantly higher following both yohimbine and mCPP challenge compared with saline infusion. The mCPP, but not yohimbine significantly increased anxiety ratings. Both challenges produced robust ACTH, cortisol and prolactin responses. There was a significant correlation between craving and the degree of alcoholism severity. Acamprosate administration did not influence craving. Both yohimbine and mCPP challenges lead to elevated alcohol craving in a clinical population of alcoholics, and these cravings correlate with alcoholism severity. Under the experimental conditions used, alcohol cravings induced by these two stimuli are not sensitive to acamprosate at clinically used doses.

Comparison of two oral symptom-triggered pharmacological inpatient treatments of acute alcohol withdrawal: clomethiazole vs. clonazepam.

AIMS: To compare two inpatient symptom-triggered pharmacological treatments of acute alcohol withdrawal (AWS) (clomethiazole vs. clonazepam). METHODS: Prospective observational comparison within a quality improvement project. Because of a need for extra precautions against complications such as seizures and severe respiratory complaints, patients with a history of withdrawal seizures or complications with clomethiazole in their history were automatically assigned to the clonazepam group. The remaining patients were alternately assigned either to the clonazepam group (n = 38 altogether) or the clomethiazole group (n = 36). Rescue medication could consist of adding either extra clonazepam or clomethiazole. Effectiveness was measured by Clinical Global Impression Scale, Revised Clinical Institute Withdrawal Assessment for Alcohol Scale, Mainz Alcohol Withdrawal Scale, Essen Self-Assessment-Alcohol Withdrawal and attrition rate. Safety and tolerability was estimated from adverse clinical events. Secondary outcome values were heart rate, blood and pulse pressure. RESULTS: There were no significant differences between the treatments with respect to primary and secondary effectiveness measures, safety or tolerability or duration of medication treatment. Both reduced the severity of initial withdrawal symptoms below 20% up to the ending of withdrawal medications. No withdrawal seizure or delirium occurred. CONCLUSION: Both score-driven treatments were equally effective, safe and well tolerated in this setting. This is the first study demonstrating the utility of clonazepam in the treatment of AWS syndrome.

Comparative study of the efficacy of ascorbic acid, quercetin, and thiamine for reversing ethanol-induced toxicity.

This study compares the curative effect of three antioxidants-ascorbic acid, quercetin, and thiamine-on ethanol-induced toxicity in rats. Administration of ethanol at a dose of 4 g/kg of body weight/day for 90 days initiated chronic alcohol-induced oxidative stress as shown by increased malondialdehyde level and DNA fragmentation in liver and brain. Ethanol administration also led to a decrease in DNA content. Activities of toxicity marker enzymes-alanine aminotransferase, aspartate aminotransferase, and γ-glutamyltranspeptidase-in liver and serum increased progressively upon ethanol administration. After ethanol administration for 90 days, the efficacy of antioxidant treatment of the alcohol-induced toxicity was studied by supplementing ascorbic acid (200 mg/100 g of body weight/day), quercetin (50 mg/kg of body weight/day), and thiamine (25 mg/kg of body weight/day) for 30 days. These groups were compared with the abstention group (not treated with ethanol). All the alterations induced by alcohol were reduced significantly by the supplementation of antioxidants and also with abstention. The regression by antioxidants was greater that of abstention. Antioxidants significantly reduced the oxidative stress induced by ethanol intoxication, increased membrane integrity, and also increased organ regeneration. Ascorbic acid was shown to be more effective than quercetin and thiamine in treating both hepatotoxicity and neurotoxicity induced by alcohol administration. This may be due to the higher antioxidant potential of ascorbic acid in physiological conditions.

Taurine prevents enhancement of acetylcholinesterase activity induced by acute ethanol exposure and decreases the level of markers of oxidative stress in zebrafish brain.

Ethanol (EtOH) is a drug widely consumed throughout the world that promotes several neurochemical disorders. Its deleterious effects are generally associated with modifications in oxidative stress parameters, signaling transduction pathways, and neurotransmitter systems, leading to distinct behavioral changes. Taurine (2-aminoethanesulfonic acid) is a ß-amino acid not incorporated into proteins found in mM range in the central nervous system (CNS). The actions of taurine as an inhibitory neurotransmitter, neuromodulator, and antioxidant make it attractive for studying a potential protective role against EtOH-mediated neurotoxicity. In this study, we investigated whether acute taurine cotreatment or pretreatment (1 h) prevent EtOH-induced changes in acetylcholinesterase (AChE) activity and in oxidative stress parameters in zebrafish brain. The results showed that EtOH exposure (1% in volume) during 1 h increased AChE activity, whereas the cotreatment with 400 mg·L(-1) taurine prevented this enhancement. A similar protective effect of 150 and 400 mg·L(-1) taurine was also observed when the animals were pretreated with this amino acid. Taurine treatments also prevented the alterations promoted in superoxide dismutase and catalase activities by EtOH, suggesting a modulatory role in enzymatic antioxidant defenses. The pretreatment with 150 and 400 mg·L(-1) taurine significantly increased the sulfydryl levels as compared to control and EtOH groups. Moreover, 150 and 400 mg·L(-1) taurine significantly decreased thiobarbituric acid reactive species (TBARS) levels, but the cotreatment with EtOH plus 400 mg·L(-1) taurine did not prevent the EtOH-induced lipoperoxidation. In contrast, the pretreatment with 150 and 400 mg·L(-1) taurine prevented the TBARS increase besides decreased the basal levels of lipid peroxides. Altogether, our data showed for the first time that EtOH induced oxidative stress in adult zebrafish brain and reinforce the idea that this vertebrate is an attractive alternative model to evaluate the beneficial effect of taurine against acute EtOH exposure.

Systemic administration of D-penicillamine prevents the locomotor activation after intra-VTA ethanol administration in rats.

Although recently published studies seem to confirm the important role displayed by acetaldehyde (ACH), the main metabolite of ethanol, in the behavioral effects of ethanol, the origin of ACH is still a matter of debate. While some authors confer more importance to the central (brain metabolism) origin of ACH, others indicate that the hepatic origin could be more relevant. In this study we have addressed this topic using an experimental approach that combines local microinjections of ethanol into the ventral tegmental area (VTA) (which guarantees the brain origin of the ACH) to induce motor activation in rats together with systemic administration (i.p.) of several doses (0, 12.5, 25 and 50 mg/kg) of D-penicillamine (DP), a sequestering agent of ACH with contrasted efficiency to abolish the behavioral effects of the drug. Our results clearly show that DP prevented in a dose-dependent manner the motor activation induced by intra-VTA ethanol, being the 50 mg/kg dose the most efficient. DP per se did not affect the basal activity of the rats. In order to determine the specificity of the DP action, we also studied the effects of DP 50 mg/kg on the DAMGO-induced motor activation after the intra-VTA administration of this mu-opioid receptors agonist. DP did not significantly modify the motor activation induced by DAMGO thus confirming the specificity of the DP effects. Our results clearly suggest that the brain-derived ACH is necessary to manifest the activating effects resulting from ethanol administration.