Effects of ethanol on cytokine production after surgery in a murine model of gram-negative pneumonia

The Early Effects of Alcohol Consumption on Functional Visual Acuity, Tear Functions, and the Ocular Surface

PURPOSE

We investigated the early effects of alcohol intake on tear functions and ocular surface health in this prospective controlled study.

METHODS

Forty-four eyes of 22 subjects (17 males, 5 females; mean age: 35.3 years) who drank 200 mL of 25% Japanese vodka and 44 eyes of age- and sex-matched 22 control subjects who drank water were investigated. Subjects were requested to refrain from alcohol consumption from the previous day and food ingestion 6 hr before the study. Each subject consumed exactly the same order prepared dinner and same quantity of alcohol over the same time frame. Subjects underwent breath alcohol level, tear evaporation and blink rate, tear lipid layer interferometry, tear film break-up time (BUT), fluorescein and Rose Bengal stainings, Schirmer test, and visual analog scale (VAS) evaluation of dry eye symptoms before, as well as 2 and 12 hr after alcohol intake.

RESULTS

The mean breath alcohol level was significantly higher in the alcohol group compared to the water group at 2 and 12 hr (P<0.001). The mean tear evaporation increased significantly from 2.5×10-7 to 8.8×10-7 gr/cm2/sec 12 hr after alcohol intake (P<0.001). The mean BUT shortened significantly from 15.0±5.0 to 5.0±2.5 sec 12 hr after alcohol intake. Lipid layer interferometry showed signs of tear film thinning 12 hr after alcohol intake in all subjects of the alcohol intake group, which was not observed in the water group. The mean blink rates increased significantly from 10.6±1.5 blinks/min to 13.5±0.9 blinks/min and 15.1±1.2 blinks/min at 2 and 12 hr, respectively, in the alcohol group (P<0.001). The Schirmer test values decreased significantly 12 hr after alcohol intake (P<0.001). The mean VAS score for dryness increased from baseline significantly in the alcohol group at 12 hr (P<0.001). No significant time-wise changes in tear functions were observed in the water group.

CONCLUSION

The tear film and ocular surface epithelia showed early and distinctive quantitative and qualitative changes associated with visual disturbances after alcohol intake.

Ethanol-Induced Alterations of T Cells and Cytokines after Surgery in a Murine Infection Model

Background

Interactions between alcohol, infection, and surgery and their effect on differentiation and functionality of T helper cells are not yet completely understood. We hypothesized that alcohol and surgery disturb differentiation of T helper cells and contribute to an impaired immune response.

Methods

Mice were treated with alcohol for two weeks. Saline treatment served as control. Clinical performance and weight were assessed. On day 14, a median laparotomy was performed and animals were challenged with Klebsiella pneumoniae intranasally. Bacterial load was determined in lungs and blood. T helper cell subpopulations and the released cytokines were assessed in lungs, spleens, and plasma. Key transcription factors of T cell differentiation were evaluated.

Results

Alcohol significantly impaired clinical appearance and body weight of animals with postsurgical infection (p < 0.05). Bacterial load was significantly higher after alcohol treatment (p < 0.05). T helper cell subsets and released cytokine levels were significantly altered in lung, but not in spleen. Expression of transcription factors of T helper cell lineage commitment did not translate into different counts of T helper cells.

Conclusions

Alcohol and surgery lead to significant cellular and functional modulations of T helper cells during postsurgical infection. These effects may contribute to an impaired immune response after surgery.

Heavy ethanol intoxication increases proinflammatory cytokines and aggravates hemorrhagic shock-induced organ damage in rats

Hemorrhagic shock (HS) following acute alcohol intoxication can increase proinflammatory cytokine production and induce marked immunosuppression. We investigated the effects of ethanol on physiopathology and cytokine levels following HS in acutely alcohol-intoxicated rats. Rats received an intravenous injection of 5 g/kg ethanol over 3 h followed by HS induced by withdrawal of 40% of total blood volume from a femoral arterial catheter over 30 min. Mean arterial pressure (MAP) and heart rate (HR) were monitored continuously for 48 h after the start of blood withdrawal. Biochemical parameters, including hemoglobin, ethanol, glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), blood urea nitrogen (BUN), creatinine (Cre), lactic dehydrogenase (LDH), and creatine phosphokinase (CPK), were measured at 30 min before induction of HS and 0, 1, 3, 6, 9, 12, 18, 24, and 48 h after HS. Serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels were measured at 1 and 12 h after HS. The liver, kidneys, and lungs were removed for pathology at 48 h later. HS significantly increased HR, blood GOT, GPT, BUN, Cre, LDH, CPK, TNF-α, and IL-6 levels and decreased hemoglobin and MAP in rats. Acute ethanol intoxication further increased serum levels of GOT, GPT, BUN, Cre, LDH, CPK, TNF-α and IL-6 elevation following HS. Acutely intoxicated rats exacerbated the histopathologic changes in the liver, kidneys, and lungs following HS.

Ethanol enhances susceptibility to apoptotic cell death via down-regulation of autophagy-related proteins

BACKGROUND

Alcohol induces cellular stress and promotes cell death in immune cells. Molecular mechanisms by which ethanol impairs the function of immune cells are largely unknown. Autophagy is a degradation pathway, acting either as a pro-survival or pro-death mechanism activated during stress conditions. We examined whether ethanol influences autophagy in monocytic human U937, CD4 Jurkat, and MCF-7 cells.

METHODS

Effects of ethanol during starvation-induced autophagy were investigated, treating cells with ethanol alone and in combination with activation of autophagy by rapamycin or inhibition by wortmannin. Apoptotic and necrotic cell death features such as the breakdown of the mitochondrial membrane potential, DNA fragmentation, and cell permeability were assessed using FACS analyses. Expression level of Beclin-1, LC3-II, Bcl-2, and the activation of caspase-3, and PARP-1 were determined using Western blot analyses. Influence of ethanol on formation of LC3-II complexes was assessed using fluorescence microscopy in MCF-7 cells stable transfected with a GFP-LC3-II-expression vector.

RESULTS

Ethanol down regulated autophagy proteins such as Beclin-1 and LC3-II. Apoptosis was enhanced as shown by breakdown of mitochondrial potential, up-regulation of cleaved caspase-3 and PARP-1 and down-regulation of anti-apoptotic protein Bcl-2. Formation of LC3-II complexes was inhibited by ethanol in caspase-3 deficient MCF-7 cells. Stimulation of autophagy by rapamycin prevented ethanol-induced apoptotic cell death. Inhibition of autophagy by wortmannin aggravated ethanol-mediated necrotic cell death.

CONCLUSION

Inhibition of autophagy via ethanol enhances susceptibility to cell death.

Adaptation of mesenteric collecting lymphatic pump function following acute alcohol intoxication

OBJECTIVE

Acute alcohol intoxication increases intestinal lymph flow by unknown mechanisms, potentially impacting mucosal immunity. We tested the hypothesis that enhanced intrinsic pump function of mesenteric lymphatics contributes to increased intestinal lymph flow during alcohol intoxication.

METHODS

Acute alcohol intoxication was produced by intragastric administration of 30% alcohol to conscious, unrestrained rats through surgically implanted catheters. Time-matched controls received either no bolus, vehicle, or isocaloric dextrose. Thirty minutes after alcohol administration, rats were anesthetized and mesenteric collecting lymphatics were isolated and cannulated to study intrinsic pumping parameters. In separate experiments, mesenteric lymphatics were isolated to examine direct effects of alcohol on intrinsic pump activity.

RESULTS

Lymphatics isolated from alcohol-intoxicated animals displayed significantly decreased CF compared to the dextrose group, elevated SVI versus all other groups, and decreased myogenic responsiveness compared to sham. Elevating pressure from 2 to 4 cm H₂O increased the volume flow index 2.4-fold in the alcohol group versus 1.4-fold for shams. Isolated lymphatics exposed to 20 mM alcohol had reduced myogenic tone, without changes in CF or SVI.

CONCLUSIONS

Alcohol intoxication enhances intrinsic pumping by mesenteric collecting lymphatics. Alcohol directly decreases lymphatic myogenic tone, but effects on phasic contractions occur by an unidentified mechanism.

Alcohol screening and risk of postoperative complications in male VA patients undergoing major non-cardiac surgery

BACKGROUND

Patients who misuse alcohol are at increased risk for surgical complications. Four weeks of preoperative abstinence decreases the risk of complications, but practical approaches for early preoperative identification of alcohol misuse are needed.

OBJECTIVE

To evaluate whether results of alcohol screening with the Alcohol Use Disorders Identification Test - Consumption (AUDIT-C) questionnaire-up to a year before surgery-were associated with the risk of postoperative complications.

DESIGN

This is a cohort study.

SETTING AND PARTICIPANTS

Male Veterans Affairs (VA) patients were eligible if they had major noncardiac surgery assessed by the VA's Surgical Quality Improvement Program (VASQIP) in fiscal years 2004-2006, and completed the AUDIT-C alcohol screening questionnaire (0-12 points) on a mailed survey within 1 year before surgery.

MAIN OUTCOME MEASURE

One or more postoperative complication(s) within 30 days of surgery based on VASQIP nurse medical record reviews.

RESULTS

Among 9,176 eligible men, 16.3% screened positive for alcohol misuse with AUDIT-C scores ≥ 5, and 7.8% had postoperative complications. Patients with AUDIT-C scores ≥ 5 were at significantly increased risk for postoperative complications, compared to patients who drank less. In analyses adjusted for age, smoking, and days from screening to surgery, the estimated prevalence of postoperative complications increased from 5.6% (95% CI 4.8-6.6%) in patients with AUDIT-C scores 1-4, to 7.9% (6.3-9.7%) in patients with AUDIT-Cs 5-8, 9.7% (6.6-14.1%) in patients with AUDIT-Cs 9-10 and 14.0% (8.9-21.3%) in patients with AUDIT-Cs 11-12. In fully-adjusted analyses that included preoperative covariates potentially in the causal pathway between alcohol misuse and complications, the estimated prevalence of postoperative complications increased significantly from 4.8% (4.1-5.7%) in patients with AUDIT-C scores 1-4, to 6.9% (5.5-8.7%) in patients with AUDIT-Cs 5-8 and 7.5% (5.0-11.3%) among those with AUDIT-Cs 9-10.

CONCLUSIONS

AUDIT-C scores of 5 or more up to a year before surgery were associated with increased postoperative complications.

Alcohol exposure as a risk factor for adverse outcomes in elective surgery

BACKGROUND AND AIMS

Alcohol consumption is a well-documented determinant of adverse perioperative outcome. We sought to determine the effect of active alcohol consumption following elective surgery.

METHODS

We queried discharge records from the American College of Surgeons' National Surgical Quality Improvement Program (NSQIP, 2005-2007) for all elective adult admissions. The 7,631 (2.5%) patients with documented alcohol use (active alcohol use of at least two drinks per day within 2 weeks of surgery; ETOH use) underwent elective surgery; 301,994 (97.5%) patients denied ETOH use. Multivariate analysis was performed with adjustments for demographic and comorbid factors. Primary outcome measures included length of stay (LOS), postoperative complications, and death.

RESULTS

ETOH use associated with elective surgery decreased over the course of the study (p < 0.0001). ETOH use was an independent predictor of pneumonia (OR 1.98, 95% CI 1.84-2.13), sepsis (OR 1.19, 95% CI 1.03-1.37), superficial surgical site infection (SSI; OR 1.15, 95% CI 1.02-1.31), wound disruption (OR 1.41, 95% CI 1.11-1.80), and prolonged LOS (OR 1.17, 95% CI 1.08-1.26). Except for SSI, these complications were independent risk factors for postoperative mortality. ETOH use was associated with earlier time to wound disruption (9 vs. 11 days; p = 0.04), longer median hospital stays (5 vs. 3 days; p < 0.0001), and longer LOS after operation (4 vs. 3 days; p < 0.0001).

CONCLUSIONS

Active alcohol consumption is a significant determinant of adverse outcomes in elective surgery; patients with ETOH use who are scheduled to undergo elective surgery should be appropriately educated and counseled.

Chronic alcohol consumption enhances myeloid-derived suppressor cells in B16BL6 melanoma-bearing mice

We previously found that chronic alcohol consumption decreases the survival of mice bearing subcutaneous B16BL6 melanoma. The underlying mechanism is still not completely understood. Antitumor T cell immune responses are important to inhibiting tumor progression and extending survival. Therefore, we examined the effects of chronic alcohol consumption on the functionality and regulation of these cells in C57BL/6 mice that chronically consumed 20% (w/v) alcohol and subsequently were inoculated subcutaneously with B16BL6 melanoma cells. Chronic alcohol consumption inhibited melanoma-induced memory T cell expansion and accelerated the decay of interferon (IFN)-gamma producing T cells in the tumor-bearing mice. Foxp3(+)CD4(+)CD25(+) regulatory T cells were not affected; however, the percentage of myeloid-derived suppressor cells (MDSC) was significantly increased in the peripheral blood and spleen. T cell proliferation as determined by carboxyfluorescein succinimidyl ester labeling experiments in vitro was inhibited by alcohol consumption relative to control water-drinking melanoma-bearing mice. Collectively, these data show that chronic alcohol consumption inhibits proliferation of memory T cells, accelerates the decay of IFN-gamma producing CD8(+) T cells, and increases MDSC, all of which could be associated with melanoma progression and reduced survival.

Cerebritis: an unusual complication of Klebsiella pneumoniae

Cerebritis is part of a continuum of brain infection and is difficult to diagnose. Cerebritis caused by Klebsiella in immunocompetent adults without predisposing factors such as neurosurgery or penetrating brain injury has not been reported before. We report a case of Klebsiella cerebritis in an adult patient with a proven extracranial focus of infection. We suggest considering cerebritis as a differential diagnosis for altered level of consciousness in patients of severe sepsis, even if an extracranial source of infection is proven.

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.