Alcohol binge before trauma/hemorrhage impairs integrity of host defense mechanisms during recovery

Tumour Necrosis Factor in Neuroplasticity, Neurogenesis and Alcohol Use Disorder

Alcohol use disorder is a pervasive and detrimental condition that involves changes in neuroplasticity and neurogenesis. Alcohol activates the neuroimmune system and alters the inflammatory status of the brain. Tumour necrosis factor (TNF) is a well characterised neuroimmune signal but its involvement in alcohol use disorder is unknown. In this review, we discuss the variable findings of TNF's effect on neuroplasticity and neurogenesis. Acute ethanol exposure reduces TNF release while chronic alcohol intake generally increases TNF levels. Evidence suggests TNF potentiates excitatory transmission, promotes anxiety during alcohol withdrawal and is involved in drug use in rodents. An association between craving for alcohol and TNF is apparent during withdrawal in humans. While anti-inflammatory therapies show efficacy in reversing neurogenic deficit after alcohol exposure, there is no evidence for TNF's essential involvement in alcohol's effect on neurogenesis. Overall, defining TNF's role in alcohol use disorder is complicated by poor understanding of its variable effects on synaptic transmission and neurogenesis. While TNF may be of relevance during withdrawal, the neuroimmune system likely acts through a larger group of inflammatory cytokines to alter neuroplasticity and neurogenesis. Understanding the individual relevance of TNF in alcohol use disorder awaits a more comprehensive understanding of TNF's effects within the brain.

Combined Effects of Repetitive Mild Traumatic Brain Injury and Alcohol Drinking on the Neuroinflammatory Cytokine Response and Cognitive Behavioral Outcomes

The relationship between alcohol consumption and traumatic brain injury (TBI) often focuses on alcohol consumption increasing the likelihood of incurring a TBI, rather than alcohol use outcomes after TBI. However, patients without a history of an alcohol use disorder can also show increased problem drinking after single or multiple TBIs. Alcohol and mild TBI share diffuse deleterious neurological impacts and cognitive impairments; therefore, the purpose of these studies was to determine if an interaction on brain and behavior outcomes occurs when alcohol is consumed longitudinally after TBI. To examine the impact of mild repetitive TBI (rmTBI) on voluntary alcohol consumption, mice were subjected to four mild TBI or sham procedures over a 2 week period, then offered alcohol (20% v/v) for 2 weeks using the two-bottle choice, drinking in the dark protocol. Following the drinking period, mice were evaluated for neuroinflammatory cytokine response or tested for cognitive and behavioral deficits. Results indicate no difference in alcohol consumption or preference following rmTBI as compared to sham; however, increases in the neuroinflammatory cytokine response due to alcohol consumption and some mild cognitive behavioral deficits after rmTBI and alcohol consumption were observed. These data suggest that the cytokine response to alcohol drinking and rmTBI + alcohol drinking is not necessarily aggregate, but the combination does result in an exacerbation of cognitive behavioral outcomes.

Injury Occurrence and Return to Dance in Professional Ballet: Prospective Analysis of Specific Correlates

Professional ballet is a highly challenging art, but studies have rarely examined factors associated with injury status in ballet professionals. This study aimed to prospectively examine gender-specific correlates of injury occurrence and time-off from injury in professional ballet dancers over a one-year period. The participants were 99 professional ballet dancers (41 males and 58 females). Variables included: (i) predictors: sociodemographic data (age, educational status), ballet-related factors (i.e., experience in ballet, ballet status), cigarette smoking, alcohol drinking, and consumption of illicit drugs; and (ii) outcomes: injury occurrence and time-off from injury. Participants were questioned on predictors at the beginning of the season, while data on outcomes were collected continuously once per month over the study period. Dancers reported total of 196 injuries (1.9 injuries (95% CI: 1.6–2.3) per dancer in average), corresponding to 1.4 injuries per 1000 dance-hours (95% CI: 1.1–1.7). In females, cigarette smoking was a predictor of injury occurrence in females (OR: 4.33, 95% CI: 1.05–17.85). Alcohol drinking was a risk factor for absence from dance in females (OR: 1.29, 95% CI: 1.01–4.21) and males (OR: 1.21, 95% CI: 1.05–3.41). Less experienced dancers were more absent from dance as a result of injury than their more experienced peers (Mann-Whitney Z: 2.02, p < 0.04). Ballet dancers and their managers should be aware of the findings of this study to make informed decisions on their behavior (dancers) or to initiate specific programs aimed at the prevention of substance use and misuse in this profession (managers).

Circulating Extracellular Vesicles and Their miR "Barcode" Differentiate Alcohol Drinkers With Liver Injury and Those Without Liver Injury in Severe Trauma Patients

Short Summary: Extracellular vesicles (EVs), released during tissue/cell injury, contain a “barcode” indicating specific microRNAs (miRs) that can uncover their origin. We examined whether systemic EVs possessing hepatic miR-signatures would indicate ongoing liver injury and clinical complications in trauma patients (TP). We grouped the patients of alcoholic drinkers into “alcohol-drinkers with liver injury (LI)” (EtOH with LI) or “alcohol-drinkers without LI” (EtOH w/o LI) and we compared these groups to “non-drinkers” (no EtOH). When we examined patient blood from the EtOH with LI group we found the total number of EVs to be increased, along with an increase in miR-122 and let7f—two EV-associated miRNAs—and several inflammation-associating cytokines, such as interleukin (IL)-6 and IL-33. In contrast, all of the aforementioned readouts were found to be decreased in the EtOH w/o LI group. These novel data demonstrate that hepatocyte damage in alcohol-intoxicated trauma patients presenting with liver injury can be reflected by an increase in circulating serum EVs, their specific miR-“barcode” and the concomitant increase of systemic inflammatory markers IL-6 and IL-33. Anti-inflammatory effect of alcohol-drinking in EtOH w/o LI can be presented by a reduced number of hepato-derived EVs, no upregulation of IL-6 and IL-33, and a miR “barcode” different from patients presenting with liver injury.

Background: Alcohol abuse is associated with (neuro)protective effects related to (head) injuries, and with negative effects regarding infection rates and survival in severely injured trauma patients (TP). Extracellular vesicles (EVs), which are released during tissue and/or cell injury, can contain a “barcode” including specific microRNAs (miRs) that uncover their origin. We examined whether EVs with a hepatic miR signature can be systemically measured, and whether they can indicate ongoing liver injury in alcohol-intoxicated TP and foretell clinical complications.

Patients/Methods: We enrolled 35 TP and measured blood EVs, IL-6, TNF-alpha, IL-1beta, IL-10 and IL-33, alcohol (ethanol, EtOH) concentration (BAC), GLDH, GGT, AST, ALT, leukocytes, platelets, and bilirubin. Within circulating EVs we measured the expression levels of miR-122, let7f, miR21, miR29a, miR-155, and miR-146a. Patients of alcohol-drinkers were grouped into “alcohol drinkers with liver injury (LI)” (EtOH with LI) or “alcohol drinkers without LI” (EtOH w/o LI) and compared to “non-drinkers” (no EtOH). We assessed systemic injury characteristics and the outcome of hospitalization with regard to sepsis, septic shock, pneumonia, or mortality.

Results: EtOH with LI patients had significantly increased rates of pneumonia vs. the EtOH w/o LI group. EVs, IL-6, and IL-33 levels were significantly increased in EtOH with LI vs. EtOH w/o LI group (p < 0.05). EV number correlated positively with ALT and IL-6 (p < 0.0001). Two miRs, miR-122 and let7f, were increased only in the blood EVs from the EtOH with LI group (p < 0.05). Five miRs, miR-122, let7f, miR-21, miR-29a, and miR-146a, were reduced in the blood EVs from the EtOH w/o LI group, vs. no EtOH (p < 0.05). Notably miR-122 correlated significantly with increased bilirubin levels in the EtOH with LI group (p < 0.05).

Conclusions: Liver injury in alcohol-intoxicated TP is reflected by increased EV numbers, their specific miR barcode, and the correlated increase of systemic inflammatory markers IL-6 and IL-33. Interestingly, severely injured TP without liver injury were found to have a reduced number of liver-derived EVs, no observed inflammatory infiltration and reduced specific miR “barcode.”

A rat model of acute kidney injury through systemic hypoperfusion evaluated by micro-US, color and PW-Doppler

AIM

To create an animal model of acute renal ischemia induced by systemic hypoperfusion, controllable and reproducible to study, in real time, hemorrhagic shock changes with micro-imaging.

ANIMALS AND METHODS

Hemorrhagic shock was induced in rats activating a syringe pump setup to remove 1 mL/min of blood, through the femoral artery catheter. The withdrawal was continued until the mean arterial pressure (MAP) dropped to 25-30 mmHg. For the next 60 min, the MAP was maintained at a constant pressure value, by automatic pump infusion and withdrawal. Micro-ultrasound imaging was performed using the Vevo 2100 system with the MS250 transducer (13-24 MHz). Renal size, morphology and echogenicity were evaluated in B-mode. Renal blood flow was evaluated using color and PW-Doppler.

RESULTS

After 1 h of ischemia, B-mode images documented slight changes in kidney echogenicity. Color and PW-Doppler analysis showed a reduction in renal blood flow in kidneys during the hypoperfusion with a progressive and significant change from baseline values of resistive index (RI). At the histological evaluation, 60 min of hypoperfusion resulted in ischemic changes in the kidneys.

CONCLUSIONS

The results of this experimental study encourage the use of the described model to study acute renal ischemia trough severe hypoperfusion. The histological data confirmed that the model was able to produce injury in renal parenchyma. It can be used to assess acute ischemic damage not only in the kidney but also in other organs by using all available dedicated small animals imaging techniques.

Sphingosine-1-Phosphate Treatment Can Ameliorate Microvascular Leakage Caused by Combined Alcohol Intoxication and Hemorrhagic Shock

Fluid resuscitation following hemorrhagic shock is often problematic, with development of prolonged hypotension and edema. In addition, many trauma patients are also intoxicated, which generally worsens outcomes. We directly investigated how alcohol intoxication impacts hemorrhagic shock and resuscitation-induced microvascular leakage using a rat model with intravital microscopic imaging. We also tested the hypothesis that an endothelial barrier-protective bioactive lipid, sphingosine-1-phosphate (S1P), could ameliorate the microvascular leakage following alcohol intoxication plus hemorrhagic shock and resuscitation. Our results show that alcohol intoxication exacerbated hemorrhagic shock and resuscitation-induced hypotension and microvascular leakage. We next found that S1P effectively could reverse alcohol-induced endothelial barrier dysfunction using both cultured endothelial cell monolayer and in vivo models. Lastly, we observed that S1P administration ameliorated hypotension and microvascular leakage following combined alcohol intoxication and hemorrhagic shock, in a dose-related manner. These findings suggest the viability of using agonists that can improve microvascular barrier function to ameliorate trauma-induced hypotension, offering a novel therapeutic opportunity for potentially improving clinical outcomes in patients with multi-hit injuries.

Impaired wound healing: facts and hypotheses for multi-professional considerations in predictive, preventive and personalised medicine

Whereas the physiologic wound healing (WH) successfully proceeds through the clearly defined sequence of the individual phases of wound healing, chronic non-healing wounds/ulcers fail to complete the individual stages and the entire healing process. There are many risk factors both modifiable (such as stress, smoking, inappropriate alcohol consumption, malnutrition, obesity, diabetes, cardio-vascular disease, etc.) and non-modifiable (such as genetic diseases and ageing) strongly contributing to the impaired WH. Current statistics demonstrate that both categories are increasingly presented in the populations, which causes dramatic socio-economic burden to the healthcare sector and society at large. Consequently, innovative concepts by predictive, preventive and personalised medicine are crucial to be implemented in the area. Individual risk factors, causality, functional interrelationships, molecular signature, predictive diagnosis, and primary and secondary prevention are thoroughly analysed followed by the expert recommendations in this paper.

Differential Relevance of NF-κB and JNK in the Pathophysiology of Hemorrhage/Resususcitation-Induced Liver Injury after Chronic Ethanol Feeding

BACKGROUND

Chronic ethanol (EtOH) abuse worsens pathophysiological derangements after hemorrhagic shock and resuscitation (H/R) that induce hepatic injury and strong inflammatory changes via JNK and NF-κB activation. Inhibiting JNK with a cell-penetrating, protease-resistant peptide D-JNKI-1 after H/R in mice with healthy livers ameliorated these effects. Here, we studied if JNK inhibition by D-JNKI-1 in chronically EtOH-fed mice after hemorrhagic shock prior to the onset of resuscitation also confers protection.

METHODS

Male mice were fed a Lieber-DeCarli diet containing EtOH or an isocaloric control (ctrl) diet for 4 weeks. Animals were hemorrhaged for 90 min (32 ± 2 mm Hg) and randomly received either D-JNKI-1 (11 mg/kg, intraperitoneally, i. p.) or sterile saline as vehicle (veh) immediately before the onset of resuscitation. Sham animals underwent surgical procedures without H/R and were either D-JNKI-1 or veh treated. Two hours after resuscitation, blood samples and liver tissue were harvested.

RESULTS

H/R induced hepatic injury with increased systemic interleukin (IL)-6 levels, and enhanced local gene expression of NF-κB-controlled genes such as intercellular adhesion molecule (ICAM)-1 and matrix metallopeptidase (MMP)9. c-Jun and NF-κB phosphorylation were increased after H/R. These effects were further increased in EtOH-fed mice after H/R. D-JNKI-1 application inhibited the proinflammatory changes and reduced significantly hepatic injury after H/R in ctrl-fed mice. Moreover, D-JNKI-1 reduces in ctrl-fed mice the H/R-induced c-Jun and NF-κB phosphorylation. However, in chronically EtOH-fed mice, JNK inhibition did not prevent the H/R-induced hepatic damage and proinflammatory changes nor c-Jun and NF-κB phosphorylation after H/R.

CONCLUSIONS

These results indicate, that JNK inhibition is protective only in not pre-harmed liver after H/R. In contrast, the pronounced H/R-induced liver damage in mice being chronically fed with ethanol cannot be prevented by JNK inhibition after H/R and seems to be under the control of NF-κB.

Acute alcohol intoxication-induced microvascular leakage

BACKGROUND

Alcohol intoxication can increase inflammation and worsen injury, yet the mechanisms involved are not clear. We investigated whether acute alcohol intoxication increases microvascular permeability and investigated potential signaling mechanisms in endothelial cells that may be involved.

METHODS

Conscious rats received a 2.5 g/kg alcohol bolus via gastric catheters to produce acute intoxication. Microvascular leakage of intravenously administered fluorescein isothiocyanate (FITC)-conjugated albumin (FITC-albumin) from the mesenteric microcirculation was assessed by intravital microscopy. Endothelial-specific mechanisms were studied using cultured endothelial cell monolayers. Transendothelial electrical resistance (TER) served as an index of barrier function, before and after treatment with alcohol or its metabolite acetaldehyde. Pharmacologic agents were used to test the roles of alcohol metabolism, oxidative stress, p38 mitogen-activated protein kinase (MAPK), myosin light-chain kinase (MLCK), rho kinase (ROCK), and exchange protein activated by cAMP (Epac). VE-cadherin localization was investigated to assess junctional integrity. Rac1 and RhoA activation was assessed by ELISA assays.

RESULTS

Alcohol significantly increased FITC-albumin extravasation from the mesenteric microcirculation. Alcohol also significantly decreased TER and disrupted VE-cadherin organization at junctions. Acetaldehyde significantly decreased TER, but inhibition of alcohol dehydrogenase or application of a superoxide dismutase mimetic failed to prevent alcohol-induced decreases in TER. Inhibition of p38 MAPK, but not MLCK or ROCK, significantly attenuated the alcohol-induced barrier dysfunction. Alcohol rapidly decreased GTP-bound Rac1 but not RhoA during the drop in TER. Activation of Epac increased TER, but did not prevent alcohol from decreasing TER. However, activation of Epac after initiation of alcohol-induced barrier dysfunction quickly resolved TER to baseline levels.

CONCLUSIONS

Our results suggest that alcohol intoxication increases microvascular permeability to plasma proteins. The data also suggest the endothelial-specific mechanism involves the p38 MAPK, Rac1, and reorganization of VE-cadherin at junctions. Last, activation of Epac can quickly resolve alcohol-induced endothelial barrier dysfunction.

Acute binge alcohol administration reverses sleep-wake cycle in Sprague Dawley rats

BACKGROUND

Binge alcohol drinking is among the most common pattern of alcohol consumption in our society. Binge alcohol consumption has serious negative consequence on mental and physical health. Although alcohol consumption is known to have profound impact on sleep, it is yet unknown as to how binge alcohol affects/alters sleep-wakefulness. The objective of this study was to examine the effect of acute binge alcohol administration on sleep-wakefulness.

METHODS

Male Sprague Dawley rats were used in the study. Under standard aseptic surgical conditions, rats (N = 7) were implanted with sleep-recording electrodes. After postoperative recovery and habituation, baseline sleep-wakefulness was recorded. Subsequently, rats were exposed to binge alcohol treatment as follows: One hour before light onset, a priming dose of 5 g/kg of alcohol was administered followed by 2 subsequent doses (adjusted based on the intoxication level of the rat) approximately 8 hours apart. Sleep-wakefulness was continuously recorded for 3 days post-binge.

RESULTS

Acute binge alcohol administration had no significant effect on sleep-wakefulness on post-binge Day 1. However, on post-binge Day 2, after blood alcohol concentration (BAC) was 0, sleep disruptions were observed manifested by a reversal of sleep-wakefulness as evident from insomnia-like symptoms (significant increase in wakefulness; significant reduction in nonrapid eye movement [NREM] sleep) during the normal sleep (light) period and excessive sleep (significant increase in NREM sleep) during the normal active (dark) period similar to excessive daytime sleepiness in humans. All sleep-wakefulness changes were normalized on Day 3 post-binge.

CONCLUSIONS

Alcohol hangover is defined as the presence of unpleasant symptoms that peak when BAC is 0. Our results suggest that the reversal of sleep-wakefulness accompanies alcohol hangover after binge alcohol administration.

Chronic ethanol feeding modulates inflammatory mediators, activation of nuclear factor-κB, and responsiveness to endotoxin in murine Kupffer cells and circulating leukocytes

Chronic ethanol abuse is known to increase susceptibility to infections after injury, in part, by modification of macrophage function. Several intracellular signalling mechanisms are involved in the initiation of inflammatory responses, including the nuclear factor-κB (NF-κB) pathway. In this study, we investigated the systemic and hepatic effect of chronic ethanol feeding on in vivo activation of NF-κB in NF-κB^EGFP reporter gene mice. Specifically, the study focused on Kupffer cell proinflammatory cytokines IL-6 and TNF-α and activation of NF-κB after chronic ethanol feeding followed by in vitro stimulation with lipopolysaccharide (LPS). We found that chronic ethanol upregulated NF-κB activation and increased hepatic and systemic proinflammatory cytokine levels. Similarly, LPS-stimulated IL-1β release from whole blood was significantly enhanced in ethanol-fed mice. However, LPS significantly increased IL-6 and TNF-α levels. These results demonstrate that chronic ethanol feeding can improve the responsiveness of macrophage LPS-stimulated IL-6 and TNF-α production and indicate that this effect may result from ethanol-induced alterations in intracellular signalling through NF-κB. Furthermore, LPS and TNF-α stimulated the gene expression of different inflammatory mediators, in part, in a NF-κB-dependent manner.

Acute alcohol intoxication prolongs neuroinflammation without exacerbating neurobehavioral dysfunction following mild traumatic brain injury

Traumatic brain injury (TBI) represents a leading cause of death and disability among young persons with ∼1.7 million reported cases in the United States annually. Although acute alcohol intoxication (AAI) is frequently present at the time of TBI, conflicting animal and clinical reports have failed to establish whether AAI significantly impacts short-term outcomes after TBI. The objective of this study was to determine whether AAI at the time of TBI aggravates neurobehavioral outcomes and neuroinflammatory sequelae post-TBI. Adult male Sprague-Dawley rats were surgically instrumented with gastric and vascular catheters before a left lateral craniotomy. After recovery, rats received either a primed constant intragastric alcohol infusion (2.5 g/kg+0.3 g/kg/h for 15 h) or isocaloric/isovolumic dextrose infusion followed by a lateral fluid percussion TBI (∼1.4 J, ∼30 ms). TBI induced apnea and a delay in righting reflex. AAI at the time of injury increased the TBI induced delay in righting reflex without altering apnea duration. Neurological and behavioral dysfunction was observed at 6 h and 24 h post-TBI, and this was not exacerbated by AAI. TBI induced a transient upregulation of cortical interleukin (IL)-6 and monocyte chemotactic protein (MCP)-1 mRNA expression at 6 h, which was resolved at 24 h. AAI did not modulate the inflammatory response at 6 h but prevented resolution of inflammation (IL-1, IL-6, tumor necrosis factor-α, and MCP-1 expression) at 24 h post-TBI. AAI at the time of TBI did not delay the recovery of neurological and neurobehavioral function but prevented the resolution of neuroinflammation post-TBI.

Intoxication by intraperitoneal injection or oral gavage equally potentiates postburn organ damage and inflammation

The increasing prevalence of binge drinking and its association with trauma necessitate accurate animal models to examine the impact of intoxication on the response and outcome to injuries such as burn. While much research has focused on the effect of alcohol dose and duration on the subsequent inflammatory parameters following burn, little evidence exists on the effect of the route of alcohol administration. We examined the degree to which intoxication before burn injury causes systemic inflammation when ethanol is given by intraperitoneal (i.p.) injection or oral gavage. We found that intoxication potentiates postburn damage in the ileum, liver, and lungs of mice to an equivalent extent when either ethanol administration route is used. We also found a similar hematologic response and levels of circulating interleukin-6 (IL-6) when either ethanol paradigm achieved intoxication before burn. Furthermore, both i.p. and gavage resulted in similar blood alcohol concentrations at all time points tested. Overall, our data show an equal inflammatory response to burn injury when intoxication is achieved by either i.p. injection or oral gavage, suggesting that findings from studies using either ethanol paradigm are directly comparable.

Preinjury alcohol exposure attenuates the neuroinflammatory response to traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) initiates a neuroinflammatory response that increases the risk of TBI-related mortality. Acute alcohol intoxication at the time of TBI is associated with improved survival. Ethanol is recognized as a systemic immunomodulator that may also impart neuroprotection. The effects of alcohol on TBI-induced neuroinflammation, however, are unknown. We hypothesized that ethanol treatment prior to TBI may provide neuroprotection by diminishing the neuroinflammatory response to injury.

MATERIALS AND METHODS

Mice underwent gavage with ethanol (EtOH) or water (H2O) prior to TBI. Animals were subjected to blunt TBI or sham injury (Sham). Posttraumatic rapid righting reflex (RRR) and apnea times were assessed. Cerebral and serum samples were analyzed by ELISA for inflammatory cytokine levels. Serum neuron-specific enolase (NSE), a biomarker of injury severity, was also measured.

RESULTS

Neurologic recovery from TBI was more rapid in H2O-treated mice compared with EtOH-treated mice. However, EtOH/TBI mice had a 4-fold increase in RRR time compared with EtOH/Sham, whereas H2O/TBI mice had a 15-fold increase in RRR time compared with H2O/Sham. Ethanol intoxication at the time of TBI significantly increased posttraumatic apnea time. Preinjury EtOH treatment was associated with reduced levels of proinflammatory cytokines IL-6, KC, MCP-1, and MIP-1α post TBI. NSE was significantly increased post injury in the H2O/TBI group compared with H2O/Sham but was not significantly reduced by EtOH pretreatment.

CONCLUSIONS

Alcohol treatment prior to TBI reduces the local neuroinflammatory response to injury. The decreased neurologic and inflammatory impact of TBI in acutely intoxicated patients may be responsible for improved clinical outcomes.

Angiotensin (1-7) contributes to nitric oxide tonic inhibition of vasopressin release during hemorrhagic shock in acute ethanol intoxicated rodents

AIMS

Acute ethanol intoxication (AEI) attenuates the arginine vasopressin (AVP) response to hemorrhage leading to impaired hemodynamic counter-regulation and accentuated hemodynamic stability. Previously we identified that the ethanol-induced impairment of circulating AVP concentrations in response to hemorrhage was the result of augmented central nitric oxide (NO) inhibition. The aim of the current study was to examine the mechanisms underlying ethanol-induced up-regulation of paraventricular nucleus (PVN) NO concentration. Angiotensin (ANG) (1-7) is an important mediator of NO production through activation of the Mas receptor. We hypothesized that Mas receptor inhibition would decrease central NO concentration and thus restore the rise in circulating AVP levels during hemorrhagic shock in AEI rats.

MAIN METHODS

Conscious male Sprague-Dawley rats (300-325 g) received a 15 h intra-gastric infusion of ethanol (2.5 g/kg+300 mg/kg/h) or dextrose prior to a fixed-pressure (~40 mm Hg) 60 min hemorrhage. The Mas receptor antagonist A-779 was injected through an intracerebroventricular (ICV) cannula 15 min prior to hemorrhage.

KEY FINDINGS

PVN NOS activity and NO were significantly higher in AEI compared to DEX-treated controls at the completion of hemorrhage. ICV A-779 administration decreased NOS activity and NO concentration, partially restoring the rise in circulating AVP level at completion of hemorrhage in AEI rats.

SIGNIFICANCE

These results suggest that Mas receptor activation contributes to the NO-mediated inhibitory tone of AVP release in the ethanol-intoxicated hemorrhaged host.

Alcohol abuse and the injured host: dysregulation of counterregulatory mechanisms review

Traumatic injury ranks as the number one cause of death for the younger than 44 years age group and fifth leading cause of death overall (www.nationaltraumainstitute.org/home/trauma_statistics.html). Although improved resuscitation of trauma patients has dramatically reduced immediate mortality from hemorrhagic shock, long-term morbidity and mortality continue to be unacceptably high during the postresuscitation period particularly as a result of impaired host immune responses to subsequent challenges such as surgery or infection. Acute alcohol intoxication (AAI) is a significant risk factor for traumatic injury, with intoxicating blood alcohol levels present in more than 40% of injured patients. Severity of trauma, hemorrhagic shock, and injury is higher in intoxicated individuals than that of sober victims, resulting in higher mortality rates in this patient population. Necessary invasive procedures (surgery, anesthesia) and subsequent challenges (infection) that intoxicated trauma victims are frequently subjected to are additional stresses to an already compromised inflammatory and neuroendocrine milieu and further contribute to their morbidity and mortality. Thus, dissecting the dynamic imbalance produced by AAI during trauma is of critical relevance for a significant proportion of injured victims. This review outlines how AAI at the time of hemorrhagic shock not only prevents adequate responses to fluid resuscitation but also impairs the ability of the host to overcome a secondary infection. Moreover, it discusses the neuroendocrine mechanisms underlying alcohol-induced hemodynamic dysregulation and its relevance to host defense restoration of homeostasis after injury.

Acute alcohol intoxication reduces mortality, inflammatory responses and hepatic injury after haemorrhage and resuscitation in vivo

BACKGROUND AND PURPOSE

Haemorrhagic shock and resuscitation (H/R) induces hepatic injury, strong inflammatory changes and death. Alcohol intoxication is assumed to worsen pathophysiological derangements after H/R. Here, we studied the effects of acute alcohol intoxication on survival, liver injury and inflammation after H/R, in rats.

EXPERIMENTAL APPROACH

Rats were given a single oral dose of ethanol (5 g·kg(-1) , 30%) or saline (control), 12 h before they were haemorrhaged for 60 min and resuscitated (H/R). Sham groups received the same procedures without H/R. Measurements were made 2, 24 and 72 h after resuscitation. Survival was assessed 72 h after H/R.

KEY RESULTS

Ethanol increased survival after H/R three-fold and also induced fatty changes in the liver. H/R-induced liver injury was amplified by ethanol at 2 h but inhibited 24 h after H/R. Elevated serum IL-6 levels as well as hepatic IL-6 and TNF-α gene expression 2 h after H/R were reduced by ethanol. Ethanol enhanced serum IL-1β at 2 h, but did not affect increased hepatic IL-1β expression at 72 h after H/R. Local inflammatory markers, hepatic infiltration with polymorphonuclear leukocytes and intercellular adhesion molecule 1 expression decreased after ethanol compared with saline, following H/R. Ethanol reduced H/R-induced IκBα activation 2 h after H/R, and NF-κB-dependent gene expression of MMP9.

CONCLUSIONS AND IMPLICATIONS

Ethanol reduced H/R-induced mortality at 72 h, accompanied by a suppression of proinflammatory changes after H/R in ethanol-treated animals. Binge-like ethanol exposure modulated the inflammatory response after H/R, an effect that was associated with NF-κB activity.

Acute ethanol gavage attenuates hemorrhage/resuscitation-induced hepatic oxidative stress in rats

Acute ethanol intoxication increases the production of reactive oxygen species (ROS). Hemorrhagic shock with subsequent resuscitation (H/R) also induces ROS resulting in cellular and hepatic damage in vivo. We examined the role of acute ethanol intoxication upon oxidative stress and subsequent hepatic cell death after H/R. 14 h before H/R, rats were gavaged with single dose of ethanol or saline (5 g/kg, EtOH and ctrl; H/R_EtOH or H/R_ctrl, resp.). Then, rats were hemorrhaged to a mean arterial blood pressure of 30 ± 2 mmHg for 60 min and resuscitated. Two control groups underwent surgical procedures without H/R (sham_ctrl and sham_EtOH, resp.). Liver tissues were harvested at 2, 24, and 72 h after resuscitation. EtOH-gavage induced histological picture of acute fatty liver. Hepatic oxidative (4-hydroxynonenal, 4-HNE) and nitrosative (3-nitrotyrosine, 3-NT) stress were significantly reduced in EtOH-gavaged rats compared to controls after H/R. Proapoptotic caspase-8 and Bax expressions were markedly diminished in EtOH-gavaged animals compared with controls 2 h after resuscitation. EtOH-gavage increased antiapoptotic Bcl-2 gene expression compared with controls 2 h after resuscitation. iNOS protein expression increased following H/R but was attenuated in EtOH-gavaged animals after H/R. Taken together, the data suggest that acute EtOH-gavage may attenuate H/R-induced oxidative stress thereby reducing cellular injury in rat liver.

Augmented central nitric oxide production inhibits vasopressin release during hemorrhage in acute alcohol-intoxicated rodents

Acute alcohol intoxication (AAI) attenuates the AVP response to hemorrhage, contributing to impaired hemodynamic counter-regulation. This can be restored by central cholinergic stimulation, implicating disrupted signaling regulating AVP release. AVP is released in response to hemorrhage and hyperosmolality. Studies have demonstrated nitric oxide (NO) to play an inhibitory role on AVP release. AAI has been shown to increase NO content in the paraventricular nucleus. We hypothesized that the attenuated AVP response to hemorrhage during AAI is the result of increased central NO inhibition. In addition, we predicted that the increased NO tone during AAI would impair the AVP response to hyperosmolality. Conscious male Sprague-Dawley rats (300-325 g) received a 15-h intragastric infusion of alcohol (2.5 g/kg + 300 mg·kg(-1)·h(-1)) or dextrose prior to a 60-min fixed-pressure hemorrhage (∼40 mmHg) or 5% hypertonic saline infusion (0.05 ml·kg(-1)·min(-1)). AAI attenuated the AVP response to hemorrhage, which was associated with increased paraventricular NO content. In contrast, AAI did not impair the AVP response to hyperosmolality. This was accompanied by decreased paraventricular NO content. To confirm the role of NO in the alcohol-induced inhibition of AVP release during hemorrhage, the nitric oxide synthase inhibitor, nitro-l-arginine methyl ester (l-NAME; 250 μg/5 μl), was administered centrally prior to hemorrhage. l-NAME did not further increase AVP levels during hemorrhage in dextrose-treated animals; however, it restored the AVP response during AAI. These results indicate that AAI impairs the AVP response to hemorrhage, while not affecting the response to hyperosmolality. Furthermore, these data demonstrate that the attenuated AVP response to hemorrhage is the result of augmented central NO inhibition.

Binge alcohol exposure modulates rodent expression of biomarkers of the immunoinflammatory response to orthopaedic trauma

BACKGROUND

Alcohol is a known modulator of the immune system and host-defense response. Alcohol abuse is common in trauma patients, although the influence of alcohol intoxication on the inflammatory response following major orthopaedic injury remains unknown. The aim of this investigation was to examine the influence of binge alcohol exposure on biomarkers of the systemic inflammatory response following bilateral traumatic femoral fracture in a rodent model.

METHODS

Ninety-two Sprague-Dawley rats were administered intraperitoneal injections of either saline solution or alcohol for three days. These animals then underwent a sham procedure or bilateral femoral intramedullary pinning and mid-diaphyseal closed fracture via blunt guillotine. The animals were killed at specific time points after the injury. Serum and lung tissue were collected, and twenty-five inflammatory markers were analyzed by immunoassay. Histological sections of lung tissue were evaluated by a board-certified pathologist.

RESULTS

Bilateral femoral fracture significantly (p < 0.05) increased multiple serum biomarkers of inflammation. Binge alcohol treatment prior to injury significantly suppressed the increase in serum levels of interleukin (IL)-6, white blood cells, IL-2, IL-10, and C-reactive protein after the fracture. However, alcohol-treated animals were found to have increased pulmonary levels of IL-6, IL-1β, IL-2, and macrophage inflammatory protein-1α following bilateral femoral fracture. In addition, lung tissue harvested following alcohol treatment and injury demonstrated increased pathologic changes, including parenchymal, alveolar, and peribronchial leukocyte infiltration and significantly elevated pulmonary wet-to-dry ratio, indicative of pulmonary edema.

CONCLUSIONS

Our results indicate that acute alcohol intake prior to bilateral femoral fracture with fixation in rats modulates the inflammatory response after injury in a tissue-dependent manner. Although serum biomarkers of inflammation were suppressed in alcohol-treated animals following injury, several measures of pulmonary inflammation including cytokine levels, histological changes, and findings of pulmonary edema were significantly increased following fracture with the presence of alcohol.

Cellular and mitochondrial effects of alcohol consumption

Alcohol dependence is correlated with a wide spectrum of medical, psychological, behavioral, and social problems. Acute alcohol abuse causes damage to and functional impairment of several organs affecting protein, carbohydrate, and fat metabolism. Mitochondria participate with the conversion of acetaldehyde into acetate and the generation of increased amounts of NADH. Prenatal exposure to ethanol during fetal development induces a wide spectrum of adverse effects in offspring, such as neurologic abnormalities and pre- and post-natal growth retardation. Antioxidant effects have been described due to that alcoholic beverages contain different compounds, such as polyphenols as well as resveratrol. This review analyzes diverse topics on the alcohol consumption effects in several human organs and demonstrates the direct participation of mitochondria as potential target of compounds that can be used to prevent therapies for alcohol abusers.

Alcohol exposure and outcomes in trauma patients

Objective

To determine the injury patterns, complications, and mortality after alcohol consumption in trauma patients.

Methods

The Trauma Registry at an American College of Surgeons (ACS) level I center was queried for all patients with a toxicology screen admitted between 1st January 2002 and 31st December 2005. Alcohol-positive (AP) patients were matched to control patients who had a completely negative screen (AN) using age, gender, mechanism, Injury Severity Score (ISS), head Abbreviated Injury Scale (AIS), chest AIS, abdominal AIS, and extremity AIS. Injuries and outcomes were compared between the groups.

Results

As many as 5,317 patients had toxicology data, of which 471 (8.9%) had a positive alcohol screen (AP). A total of 386 AP patients were then matched to 386 control (AN) patients. The AP group had a significantly higher mortality than the AN group overall (23 vs. 13%; p < 0.001), and by ISS stratification: ISS < 16 (6 vs. 0.4%; p < 0.001), ISS 16–25 (53 vs. 28%; p = 0.01), and ISS > 25 (90 vs. 67%; p = 0.01). AP patients had a higher incidence of admission systolic blood pressure < 90 (18 vs. 10%; p < 0.001) and Glasgow Coma Scale (GCS) score ≤ 8 (25 vs. 17%; p = 0.002). AN patients had a significantly higher incidence of hemopneumothorax (11 vs. 7%; p = 0.03), while AP patients had a higher incidence of cardiac arrest (8 vs. 3%; p = 0.004). There was no difference in intensive care unit (ICU) and hospital length of stay.

Conclusion

In a mixed population of trauma patients, an AP screen is associated with an increased incidence of admission hypotension and depressed GCS score. In this case-matched study, alcohol exposure appeared to increase mortality after injury.

Pathogenesis of alcoholic liver disease: the role of nuclear receptors

Ethanol consumption causes fatty liver, which can lead to inflammation, fibrosis, cirrhosis and even liver cancer. The molecular mechanisms by which ethanol exerts its damaging effects are extensively studied, but not fully understood. It is now evident that nuclear receptors (NRs), including retinoid x receptor alpha and peroxisome proliferator-activated receptors, play key roles in the regulation of lipid homeostasis and inflammation during the pathogenesis of alcoholic liver disease (ALD). Given their pivotal roles in physiological processes, NRs represent potential therapeutic targets for the treatment and prevention of numerous metabolic and lipid-related diseases including ALD. This review summarizes the factors that contribute to ALD and the molecular mechanisms of ALD with a focus on the role of NRs.

Transient central cholinergic activation enhances sympathetic nervous system activity but does not improve hemorrhage-induced hypotension in alcohol-intoxicated rodents

Morbidity and mortality after traumatic injury and hemorrhagic shock (HS) are exacerbated in the alcohol-intoxicated individual. The level of hypotension at the time of admittance into the emergency department is a critical indicator of outcome from injury. Previously, we have demonstrated that acute alcohol intoxication (AAI) decreases basal mean arterial blood pressure (MABP), exaggerates hypotension throughout HS, and attenuates the pressor response to fluid resuscitation in male rodents. This AAI-induced impaired hemodynamic counter-regulation to blood loss is associated with dampened neuroendocrine activation (i.e., epinephrine, norepinephrine, and arginine vasopressin [AVP] release). We hypothesize that the blunted neuroendocrine response is the principal mechanism involved in hemodynamic instability during and after HS in AAI. The present study investigates whether enhancing central cholinergic activity via intracerebroventricular (ICV) choline, a precursor of acetylcholine, would restore the neuroendocrine response and, as a result, improve hemodynamic compensation after HS. Chronically catheterized, conscious, male Sprague-Dawley rats (225-250 g) received a primed 15-h alcohol infusion (30% wt/vol; total approximately 8 g x kg(-1)) before ICV choline (150 microg) injection and were subsequently subjected to fixed-volume HS (50%) and fluid resuscitation with lactated Ringer's solution (2x volume removed). There were a total of eight experimental groups (n = 5-12 rats per group): alcohol-treated not hemorrhaged (alcohol/sham), dextrose-treated not hemorrhaged (dextrose/sham), alcohol-treated hemorrhaged (alcohol/hemorrhage), and dextrose-treated hemorrhaged (dextrose/hemorrhage), with ICV choline or water injection. Intracerebroventricular choline immediately increased basal MABP in both control (16%) and AAI animals (12%), but did not alter MABP after HS in either group. Intracerebroventricular choline increased basal plasma epinephrine (196%), norepinephrine (96%), and AVP (145%) and enhanced the HS-induced increase in epinephrine and AVP, without altering norepinephrine responses to HS, in control animals. Acute alcohol intoxication blunted choline-induced neuroendocrine activation and prevented the HS-induced increase in norepinephrine, without affecting post-HS epinephrine and AVP levels. Intracerebroventricular choline administration to AAI animals enhanced the HS-induced increase in epinephrine without affecting post-HS norepinephrine or AVP. These results indicate that ICV choline produced immediate neuroendocrine activation and elevation in MABP that was not sustained sufficiently to improve hemodynamic counter-regulation in alcohol-treated animals.

Central acetylcholinesterase inhibition improves hemodynamic counterregulation to severe blood loss in alcohol-intoxicated rats

Acute alcohol intoxication results in impaired hemodynamic counterregulation to blood loss and is associated with an attenuated hemorrhage-induced release of catecholamines and AVP. We speculated that restoration of the neuroendocrine response to hemorrhage would improve mean arterial blood pressure (MABP) recovery during acute alcohol intoxication. Previously, we demonstrated that intracerebroventricular (i.c.v.) choline, a precursor of acetylcholine, transiently increases sympathetic nervous system (SNS) outflow but is not capable of improving neuroendocrine and hemodynamic compensation to hemorrhage in alcohol-treated rats. We hypothesized that prolongation of the observed effect via i.c.v. neostigmine, an acetylcholinesterase inhibitor, would enhance SNS outflow, restore the neuroendocrine response, and in turn improve hemodynamic responses to hemorrhage during acute alcohol intoxication. I.c.v. neostigmine (1 microg) increased MABP, catecholamines, and AVP within 5 min and reversed hypotension due to 40% hemorrhage and intragastric alcohol (30% wt/vol, 2.5 g/kg) administration in chronically catheterized male Sprague-Dawley rats (225-250 g body wt). Acute alcohol intoxication before 50% hemorrhage decreased basal MABP, accentuated hypotension midhemorrhage, suppressed the hemorrhage-induced release of norepinephrine and AVP, and prevented restoration of MABP to basal levels after fluid resuscitation with lactated Ringer solution. I.c.v. neostigmine (0.5 microg) produced a sustained increase in MABP beginning at 30 min of hemorrhage that persisted throughout fluid resuscitation in control and alcohol-treated animals. I.c.v. neostigmine enhanced epinephrine responses and restored the hemorrhage-induced release of norepinephrine and AVP in alcohol-treated rats. These results demonstrate that inhibition of acetylcholinesterase in the central nervous system enhances SNS outflow, restores the neuroendocrine response to severe blood loss, and thereby improves hemodynamic counterregulation during acute alcohol intoxication. This study provides evidence for a central (and not peripheral) role of alcohol in impairing hemodynamic stability during hemorrhagic shock.

Alcohol and trauma: a summary of the Satellite Symposium at the 30th Annual Meeting of the Shock Society

This article highlights the research presented at the Alcohol and Trauma Satellite Symposium at the 30th Annual Meeting of the Shock Society. The satellite meeting was held on June 8 and 9 in Baltimore, MD. Its purpose was to discuss recent findings in the areas of alcohol and injury, including the effect of alcohol use on patients in the trauma unit of hospitals. The meeting consisted of three sessions, with plenary talks by invited speakers, short talks from selected abstracts, and a poster session. Participants presented data on the effects of alcohol on organ function, healing, and immune processes after a variety of injuries including burn, hemorrhagic shock, sepsis, and ischemia reperfusion.

Pathoanatomy and clinical correlates of the immunoinflammatory response following orthopaedic trauma

The natural inflammatory response to major trauma may be associated with the development of a systemic inflammatory state, remote multiorgan failure, and death. Although a controlled inflammatory response is beneficial, an exaggerated response can cause serious adverse systemic effects. Early identification of high-risk patients, based on inflammatory markers and genomic predisposition, should help direct intervention in terms of surgical stabilization and biologic response modification. Currently, two markers of immune reactivity, interleukin-6 and human leukocyte antigen-DR class II molecules, appear to have the most potential for regular use in predicting the clinical course and outcome in trauma patients; however, the ability to measure markers of inflammation is still limited at many hospitals. With improving technology and increasing research interest, understanding of the significance of the immunoinflammatory response system in injured patients will continue to evolve.

Binge drinking in young adults: Data, definitions, and determinants

Binge drinking is an increasingly important topic in alcohol research, but the field lacks empirical cohesion and definitional precision. The present review summarizes findings and viewpoints from the scientific binge-drinking literature. Epidemiological studies quantify the seriousness of alcohol-related problems arising from binge drinking, with a growing incidence reported in college-age men over the last 2 years. Experimental studies have found neurocognitive deficits for frontal lobe processing and working memory operations in binge-drinking compared with nonbinge alcohol drinkers. The findings are organized with the goals of providing a useful binge-drinking definition in the context of the empirical results. Theoretical implications are discussed on how binge drinking may alter neurophysiological and neurocognitive function.

In vitro and in vivo models of acute alcohol exposure

Alcohol abuse is a global problem due to the financial burden on society and the healthcare system. While the harmful health effects of chronic alcohol abuse are well established, more recent data suggest that acute alcohol consumption also affects human wellbeing. Thus, there is a need for research models in order to fully understand the effect of acute alcohol abuse on different body systems and organs. The present manuscript summarizes the interdisciplinary advantages and disadvantages of currently available human and non-human models of acute alcohol abuse, and identifies their suitability for biomedical research.

A recent perspective on alcohol, immunity, and host defense

BACKGROUND

Multiple line of clinical and experimental evidence demonstrates that both acute, moderate, and chronic, excessive alcohol use result in various abnormalities in the functions of the immune system.

METHODS

Medline and PubMed databases were used to identify published reports with particular interest in the period of 2000-2008 in the subject of alcohol use, infection, inflammation, innate, and adaptive immunity.

RESULTS

This review article summarizes recent findings relevant to acute or chronic alcohol use-induced immunomodulation and its consequences on host defense against microbial pathogens and tissue injury. Studies with in vivo and in vitro alcohol administration are both discussed. The effects of alcohol on lung infections, trauma and burn injury, liver, pancreas, and cardiovascular diseases are evaluated with respect to the role of immune cells. Specific changes in innate immune response and abnormalities in adaptive immunity caused by alcohol intake are detailed.

CONCLUSION

Altered inflammatory cell and adaptive immune responses after alcohol consumption result in increased incidence and poor outcome of infections and other organ-specific immune-mediated effects.

Further preliminary assessment of three human glioma cell lines as models of human astrocytic toxicity in vitro

Three human astroglioma lines U251-MG, U373-MG and CCF-STTG1 have been evaluated further as possible models for astrocytotoxicity (GFAP and IL-6 release). The effects of bacterial lipopolysaccharide, chloroquine diphosphate and acrylamide were studied on GFAP expression and LPS, chloroquine diphosphate, ethanol, trimethyltin chloride (TMTC) and acrylamide were examined on interleukin-6 (IL-6) release in the U373-MG line only. At 4-h LPS elevated GFAP (17.0±5.0% P<0.05) above control in the U251-MG cell line only. Chloroquine diphosphate over 4h in the U251-MG line resulted in an increase in GFAP-IR to 20.3±4.2% and 21.1±4.1% above control levels 0.1μM (P<0.05) and 1μM (P<0.05) respectively. CQD was associated with decreases in MTT turnover, particularly after 24h incubation. With the U373-MG line, LPS (0.5μg/ml) increased IL-6 expression 640% above control (P<0.001), whilst chloroquine diphosphate (100μM), ethanol (10mM) and TMTC chloride (1μM) also increased IL-6. It is possible that batteries of astrocytic human glioma cell lines may be applicable to the sensitive evaluation of toxicants on astrogliotic expression markers such as GFAP and IL-6.