Neutrophil elastase activity and superoxide production are diminished in neutrophils of alcoholics

Impact of Alcohol on Inflammation, Immunity, Infections, and Extracellular Vesicles in Pathogenesis

Alcohol consumption is a widespread social activity with a complex and multifaceted impact on human health. Although moderate alcohol consumption has been associated with certain potential health benefits, excessive or chronic alcohol use can disrupt the body's immune balance, promote inflammation, and increase susceptibility to infections. The deleterious effects associated with alcohol toxicity include the loss of cell integrity. When cells lose their integrity, they also lose the capacity to communicate with other systems. One of the systems disturbed by alcohol toxicity is extracellular vesicle (EV)-mediated communication. EVs are critical mediators of cell-to-cell communication. They play a significant role in alcohol-induced pathogenesis, facilitating communication and molecular exchange between cells, thereby potentially contributing to alcohol-related health issues. Investigating their involvement in this context is fundamental to resolving the intricate mechanisms behind the health consequences of alcohol use and may pave the way for innovative approaches for mitigating the adverse effects of alcohol on immune health. Understanding the role of EVs in the context of alcohol-induced pathogenesis is essential for comprehending the mechanisms behind alcohol-related health issues.

Sponge-Derived 24-Homoscalaranes as Potent Anti-Inflammatory Agents

Scalarane-type sesterterpenoids are known for their therapeutic potential in cancer treatments. However, the anti-inflammatory properties of this class of metabolites remain elusive. Our current work aimed to investigate the anti-inflammatory scalaranes from marine sponge Lendenfeldia sp., resulting in the isolation of six new 24-homoscalaranes, lendenfeldaranes E–J (1–6). The structures of the new metabolites were determined by extensive spectroscopic analyses, and the absolute configuration of 1 was established by electronic circular dichroism (ECD) calculations. Compounds 2 and 3 were discovered to individually reduce the generation of superoxide anions, and compound 1 displayed an inhibitor effect on the release of elastase. These three compounds were proven to be the first anti-neutrophilic scalaranes.

Chronic alcohol abuse affects the clinical course and outcome of community-acquired bacterial meningitis

The aim of the study was to determine the effect of chronic alcohol abuse on the course and outcome of bacterial meningitis (BM). We analyzed records of patients with BM who were hospitalized between January 2010 and December 2017 in the largest neuroinfection center in Poland. Out of 340 analyzed patients, 45 (13.2%) were alcoholics. Compared with non-alcoholics, alcoholics were more likely to present with seizures (p < 0.001), scored higher on the Sequential Organ Failure Assessment (SOFA) (p = 0.002) and lower on the Glasgow Coma Scale (GCS) (p < 0.001), and had worse outcome as measured by the Glasgow Outcome Score (GOS) (p < 0.001). Furthermore, alcoholics were less likely to complain of headache (p < 0.001) and nausea/vomiting (p = 0.005) and had lower concentration of glucose in cerebrospinal fluid (CSF) (p = 0.025). In the multiple logistic regression analysis, alcoholism was associated with lower GCS (p = 0.036), presence of seizures (p = 0.041), male gender (p = 0.042), and absence of nausea/vomiting (p = 0.040). Furthermore, alcoholism (p = 0.031), lower GCS score (p = 0.001), and higher blood urea concentration (p = 0.018) were independently associated with worse outcome measured by GOS. Compared with non-alcoholics, chronic alcohol abusers are more likely to present with seizures, altered mental status, and higher SOFA score and have an increased risk of unfavorable outcome. In multivariate analysis, seizures and low GCS were independently associated with alcoholism, while alcoholism was independently associated with worse outcome.

Alcohol, Aldehydes, Adducts and Airways

Drinking alcohol and smoking cigarettes results in the formation of reactive aldehydes in the lung, which are capable of forming adducts with several proteins and DNA. Acetaldehyde and malondialdehyde are the major aldehydes generated in high levels in the lung of subjects with alcohol use disorder who smoke cigarettes. In addition to the above aldehydes, several other aldehydes like 4-hydroxynonenal, formaldehyde and acrolein are also detected in the lung due to exposure to toxic gases, vapors and chemicals. These aldehydes react with nucleophilic targets in cells such as DNA, lipids and proteins to form both stable and unstable adducts. This adduction may disturb cellular functions as well as damage proteins, nucleic acids and lipids. Among several adducts formed in the lung, malondialdehyde DNA (MDA-DNA) adduct and hybrid malondialdehyde-acetaldehyde (MAA) protein adducts have been shown to initiate several pathological conditions in the lung. MDA-DNA adducts are pre-mutagenic in mammalian cells and induce frame shift and base-pair substitution mutations, whereas MAA protein adducts have been shown to induce inflammation and inhibit wound healing. This review provides an insight into different reactive aldehyde adducts and their role in the pathogenesis of lung disease.

Alcohol abuse and pulmonary disease

ARDS is a severe form of lung injury characterized by increased permeability of the alveolar capillary membrane, diffuse alveolar damage, the accumulation of proteinaceous interstitial and intra-alveolar edema, and the presence of hyaline membranes. These pathological changes are accompanied by physiological alterations, including severe hypoxemia, an increase in pulmonary dead space, and decreased pulmonary compliance. Approximately 200,000 individuals develop ARDS in the United States each year, and nearly 50% of these patients have a history of alcohol abuse. We have identified alcohol abuse as an independent risk factor for the development of ARDS, and more recent studies have validated these findings in patients following lung resection and blood transfusion. In ARDS survivors, alcohol abuse is also associated with an increased duration of mechanical ventilation and prolonged ICU length of stay. Despite studies aimed at improving outcomes in patients with ARDS, the mortality remains high at > 40%]. For those who abuse alcohol, the mortality is even higher, at 65%. In this review, we will discuss the relationship between alcohol abuse and ARDS, the effects of alcohol abuse on pulmonary function, and future directions and potential therapeutic targets for patients at risk for ARDS as a result of alcohol abuse, which impairs immune function, decreases pulmonary antioxidant capacity, decreases alveolar epithelial cell function, alters activation of the renin angiotensin system, and impairs GM-CSF signaling. These pathways represent potential therapeutic targets for patients at risk for ARDS as a result of alcohol abuse.

Mechanisms of neutrophil accumulation in the lungs against bacteria

Bacterial lung diseases are a major cause of morbidity and mortality both in immunocompromised and in immunocompetent individuals. Neutrophil accumulation, a pathological hallmark of bacterial diseases, is critical to host defense, but may also cause acute lung injury/acute respiratory distress syndrome. Toll-like receptors, nucleotide-binding oligomerization domain (NOD)-like receptors, transcription factors, cytokines, and chemokines play essential roles in neutrophil sequestration in the lungs. This review highlights our current understanding of the role of these molecules in the lungs during bacterial infection and their therapeutic potential. We also discuss emerging data on cholesterol and ethanol as environmentally modifiable factors that may impact neutrophil-mediated pulmonary innate host defense. Understanding the precise molecular mechanisms leading to neutrophil influx in the lungs during bacterial infection is critical for the development of more effective therapeutic and prophylactic strategies to control the excessive host response to infection.

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.

Effects of ethanol on pulmonary inflammation in postburn intratracheal infection

Infectious complications are a major cause of mortality in trauma patients. Burn patients with prior ethanol exposure have a worse prognosis than those who sustain injury but had not been drinking. We examined pulmonary infection and lung pathology in mice given ethanol (1.2 g/kg) 30 minutes before being subjected to 13 to 15% total body surface area scald burn followed by intratracheal inoculation with Pseudomonas aeruginosa (1-2 x 10(3) colony-forming units [CFUs]). Survival was monitored for up to 48 hours. Sham control groups had 100% survival after intratracheal infection regardless of ethanol exposure. Infected burned animals had 55% survival; however, survival of infected mice exposed to ethanol and burn injury was significantly lower (27%, P < .0001). When pulmonary infection was evaluated, the lungs of sham groups were negative for bacterial colonies. In addition, at 24 hours there were no significant differences in lung CFUs from infected burned animals regardless of ethanol exposure (3.0 x 10(4)). However, pulmonary bacterial content significantly decreased (1.2 x 10, P < .02) at 48 hours in mice given burn injury alone, where CFUs from the lungs of mice exposed to ethanol prior to burn did not decline (5.4 x 10(5)). At the same time point, lungs from animals given ethanol and burn injury had about a 2-fold (P < .02) increase in leukocyte infiltration and vascular congestion, as well as decreased pulmonary oxygen saturation (82.8%, P < .02), when compared with other treatment groups. In summary, ethanol exposure in postburn intratracheal infection results in the inability to clear pulmonary infection marked by a prolonged pulmonary leukocyte accumulation and a decrease in pulmonary function.

Alcohol abuse in the critically ill patient

Alcohol abuse and dependence disorders are common in the 10% of hospitalised patients who need admission to the intensive care unit (ICU), but these disorders are often undiagnosed. The systemic effects from the excessive use of alcohol increase susceptibility to, or directly cause various important disorders in the critically ill. Early recognition of alcohol abuse and dependence is necessary and should prompt consideration of several alcohol-specific diagnoses that have important prognostic and therapeutic implications for these patients. We discuss the use of screening tests to improve the identification of alcohol abuse and dependence disorders, the epidemiology and pathogenesis of important alcohol-related disorders, differences in the presentation of several common alcohol-related diagnoses in the ICU, and important alcohol-specific therapies.

Alcohol consumption, lung function, and quality of life in pneumoconiosis

BACKGROUND

To our knowledge, there are no previous data on drinking problems in patients with pneumoconiosis. The aim of this study was to examine drinking patterns and the impact of drinking on lung function and health-related quality of life (HRQOL) in Chinese patients with pneumoconiosis.

METHODS

Three hundred patients with pneumoconiosis were recruited from a community-based case registry. The HRQOL was measured with the St. George's Respiratory Questionnaire (SGRQ). Pulmonary function, comorbidity, and psychosocial variables were also assessed. The alcohol use of the patients was evaluated with the Alcohol Use Disorders Identification questionnaire.

RESULTS

Of the 300 patients, 72.3% (217) reported that they had not consumed any alcohol during the past year, whereas 83 patients (27.7%) did report drinking alcohol. In the drinking group, 88.0% (73) consumed <7 standard drinks per week, and none of them exceeded the safety limit of 21 standard drinks per week. The drinking group (n = 83) was younger, had less concurrent medical diseases, and lower (i.e., better) unadjusted SGRQ symptom, activity, impact, and total scores than the nondrinking group (n = 217). The SGRQ scores, which were adjusted for age, duration of occupation, concurrent medical diseases, smoking status, and forced expiratory volume in 1 sec predicted tests (FEV1%), remained significantly lower for the drinking group. Although the drinking group had a higher unadjusted FEV1% predicted, the difference between the FEV1% of the two groups, after adjustment for covariates, was of borderline significance only.

CONCLUSIONS

Most Chinese patients with pneumoconiosis in this study did not consume alcohol, and among those who did, the level of alcohol consumption was low. This low level of alcohol consumption was associated with a better HRQOL and possibly with better lung function.

Deficient phospholipase C activity in blood polimorphonuclear neutrophils from patients with liver cirrhosis

BACKGROUND/AIMS

Circulating neutrophils from cirrhotic patients have a reduced capacity to generate superoxide anion (O(2)(-)), which might contribute to frequent bacterial infections in these patients. We studied the signal transduction pathways involved in the generation of O(2)(-) in neutrophils from 98 cirrhotic patients and 46 healthy controls.

METHODS

We measured O(2)(-) production in neutrophils induced by fMLP, opsonized zymosan, TNF alpha, NaF, AlF(4)(-), A23187 and phorbol myristate acetate. Furthermore, we measured phospholipase C activity in neutrophils from healthy controls and end-stage cirrhotic patients.

RESULTS

O(2)(-) production was decreased in neutrophils from patients in response to fMLP, opsonized zymosan and TNF alpha. Likewise, response of these cells to G-protein stimulation by fluorides was also decreased. These reduced responses correlated significantly with the degree of liver dysfunction. On the contrary, neutrophils from patients responded normally to A23187 and phorbol esters stimulation indicating that Ca(2+)- and PKC-dependent pathways are intact in these cells. Finally, phospholipase C activity was markedly reduced in neutrophils from end-stage liver cirrhosis.

CONCLUSIONS

These data confirm that O(2)(-) generation by neutrophils is decreased in patients with cirrhosis, particularly in those with more severe liver dysfunction, and suggest that this defect involves phosphatidylinositol specific phospholipase C activity.

Acquired disorders of phagocyte function complicating medical and surgical illnesses

There is evidence that acquired dysfunction of neutrophils, monocytes, or macrophages is an important cause of infection in patients with diabetes mellitus, renal or hepatic failure, alcoholism, autoimmune diseases, influenza or human immunodeficiency virus infection, burns, and trauma. Distinguishable mechanisms of acquired phagocyte dysfunction include inhibitory effects of metabolic disturbances (e.g., hyperglycemia, uremia), chemical toxins (e.g., ethanol), viral proteins on phagocyte activation, and pathologic activation of phagocytes in the circulation (e.g., after hemodialysis, burns, or cardiopulmonary bypass). Although the burden of morbidity and mortality resulting from acquired phagocyte dysfunction appears to be vast, research in this area has been hampered by the complexity of the underlying illnesses and by limitations of laboratory assays and clinical study methodology. Given the advent of improved assays of phagocyte functions and treatments that can enhance these functions, there is a pressing need for more prospective studies of acquired phagocyte dysfunction.

Patients with stable uncomplicated cirrhosis have normal neutrophil function

BACKGROUND

Neutrophil function has been reported to be abnormal in patients with cirrhosis. In order to evaluate the relative contribution of hepatocellular dysfunction and portalsystemic shunting of blood to these abnormalities, neutrophil function was studied in 18 patients with cirrhosis and portal hypertension. Nine patients, with extrahepatic portal hypertension (EPH) caused by portal vein thrombosis, who had no clinical, biochemical or histologic evidence of liver disease were also studied.

METHODS

Superoxide generation, phagocytosis, degranulation, leukotriene B4 release, candidacidal activity and quantitative and qualitative expression of the cell surface adhesive marker CD11b/CD18 were measured in these patients as well as in age- and gender-matched controls.

RESULTS

Patients with cirrhosis were found to have a small but statistically significant decrease in the expression of the CD18 component of MAC1 in N-formyl-methionyl-leucyl-phenylalanine-stimulated neutrophils (P = 0.04). No significant differences were found between either of the two patient groups and the control group for any of the other parameters of neutrophil function tested.

CONCLUSIONS

These were unexpected findings in the light of data published elsewhere, which indicate impaired neutrophil function in patients with cirrhosis. The study suggests that patients with stable, uncomplicated cirrhosis and patients with EPH have normal neutrophil function.

Alcohol, smoking and lung disease

Alcohol and smoking are two well-known health hazards. Alcohol and tobacco consumption are strongly correlated and heavy drinkers have more trouble quitting smoking than do light drinkers. Death from tobacco-related causes was more common than alcohol-related death in a follow-up study on patients admitted to an addiction programme for treatment of alcoholism and non-nicotine drug dependence. In British male doctors in the middle and elderly age group, a protective effect of light and moderate alcohol consumption (1-3 British units of alcohol per day) compared with abstinence has been shown in one large survey. This protective effect was shown in overall mortality as well as in mortality from respiratory disease. Higher alcohol intakes were associated with an increase in mortality. This characteristic U-formed, or J-formed, dose-response curve has been found in most studies with an apparent beneficial effect of modest alcohol intake and a harmful effect of high intakes. The anti-inflammatory effect of alcohol has been considered to be responsible for its limited protective effect on smoking-related lung function decline. Recently, a hitherto unconfirmed report suggests that the beneficial effect of alcohol on lung function in men is restricted to subjects with Lewis-negative blood group (10% of the Caucasian population). On the other hand, the protective effect in those individuals is large enough to be clinically relevant. Prospective investigations including both men and women are needed to elucidate which individuals have a protective effect of light and moderate alcohol intake. The major deleterious effect of smoking, including passive smoking, must be kept in mind-drinking alcohol surrounded by cigarette smoke might not be beneficial for respiratory health.

Isotonic ethanol inhibits the generation of superoxide anion in neutrophils by inducing cell expansion

The effects of ethanol on the production of oxygen-derived free radicals by neutrophils are controversial. Osmolarity-mediated alteration of cell volume appears to be an important mechanism for regulating neutrophil activity. We investigated in neutrophils from healthy volunteers the effect of isotonic/hypertonic ethanol on both chemiluminescence amplified by a Cypridina luciferin analog in response to N-formyl-Met-Lue-Phe and cell volume measured with a Coulter counter. Both isotonic and hypertonic ethanol significantly decreased chemiluminescence in a dose-dependent manner. Isotonic ethanol produced a greater magnitude of inhibition than hypertonic ethanol (P<0.01). Another permeable molecule, urea, and hypotonic solution had the same effects on chemiluminescence. Isotonic and hypertonic ethanol caused a prompt cell expansion and shrinking, respectively. On the other hand, isotonic sucrose, an impermeable molecule, was ineffective in both chemiluminescence and cell volume changes. These data suggest that isotonic ethanol inhibits the superoxide anion production by inducing cell expansion probably due to increased intracellular osmotic pressure caused by rapid ethanol permeation through the plasmalemma. This impaired neutrophil function may, in some part, contribute to the susceptibility to infection in alcoholics.

Clinically relevant concentrations of ethanol attenuate primed neutrophil bactericidal activity

BACKGROUND

Acute alcohol intoxication is associated with an increased risk of infection in the injured patient. The impact of clinically relevant levels of ethanol (ETOH) on neutrophil (PMN) bactericidal activity remains ill-defined. PMN priming optimizes microbicidal activity by enhancing oxygen radical production, degranulation, and adhesion molecule up-regulation. We hypothesized that clinically relevant levels of ETOH attenuate these primed PMN responses critical to eradicate infection.

METHODS

After incubation with ETOH (0-1.0%), isolated human PMNs were primed with beta-acetyl-gamma-O-alkyl and activated with N-formyl-methionyl-leucyl-phenylalanine. Superoxide generation was measured by cytochrome c reduction, elastase release was measured by cleavage of methoxysuccinyl-ala-ala-pro-val-p-nitroanilide, and CD11b was measured by fluorescent monoclonal antibody staining. Bactericidal activity was assessed by Staphylococcus aureus killing.

RESULTS

ETOH attenuated superoxide production dose-dependently with significance at 0.3% ETOH. Elastase release was attenuated starting at 0.2% ETOH, and CD11b expression was reduced starting at 0.4% ETOH. S. aureus killing was impaired dose-dependently with significance at 0.3% ETOH.

CONCLUSION

Clinically relevant concentrations of ETOH attenuate PMN functions critical in host defense against invading pathogens. These results provide direct in vitro evidence consistent with previous in vivo data that acute alcohol intoxication is important in the pathogenesis of trauma-related infections.

Human neutrophil functions are inhibited in vitro by clinically relevant ethanol concentrations

Neutrophils [polymorphonuclear neutrophils (PMNs)] play a pivotal role in host defense in man. These defenses may be compromised, however, in alcohol users and abusers. We therefore evaluated the effect of ethanol levels (12.5 to 500 mg/dl), on key functions of human PMNs-chemotaxis and production of reactive oxygen species-and on changes in cytosolic-free calcium ([Ca2+]i), a pivotal intracellular mechanism of PMN activation. Ethanol significantly inhibited chemotaxis as evaluated by formyl-methionyl-leucyl-phenylalanine (fMLP)-induced upregulation of surface adhesion molecules (CD11b). fMLP-induced PMN elongation was only inhibited by a very high ethanol concentration of 500 mg/dl. Production of reactive oxygen species by normal PMNs was assessed by either chemiluminescence (CL) for hypochlorous acid or ferricytochrome c reduction (FCR) for superoxide anions. For PMN stimulated by fMLP, ethanol inhibited CL but not FCR. For PMNs activated by phorbol myristate acetate, ethanol inhibited both CL and FCR. Ethanol did not alter baseline [Ca2+]i, as assessed by videomicroscopy using the Ca(2+)-sensing fluorescent dye Fura-2-AM, but did significantly potentiate the increase in peak [Ca2+]i levels that occurs in response to stimulation by fMLP. Calcium channel blockers attenuated ethanol's inhibition of CL. Thus, acute in vitro ethanol, at clinically relevant concentrations, can inhibit several critical aspects of PMN functions. But, in PMNs, unlike neural cells, these inhibitory effects do not seem to be mediated by decreases in Ca2+ influx or in [Ca2+]i.

Polymorphonuclear leukocytes in ischemic vascular disease

Over the last decade, an extensive amount of evidence has accumulated which implicates PMN in the etiology and pathophysiology of ischemic/thrombotic diseases. It has become apparent that PMN infiltration is not, as once thought, an innocent secondary phenomenon following ischemia. Rather, PMN are active participants in the pathophysiology of infarction, exacerbating the tissue damage. Since the development of means to achieve reperfusion after thrombosis, this phenomenon has become of critical importance. Many different approaches, targeted at prevention of PMN trapping in the capillaries of the ischemic, area, have been shown to effectively reduce the final infarct size, and will likely prove valuable adjuncts to reperfusion. However, perhaps the most significant aspect of the realization that PMN play a significant role in thrombotic disease may prove to be the potential for early intervention: Elevated PMN counts are predictive of ischemic events, and there is preliminary evidence that the elevated PMN count may be also associated with increased PMN activation, suggesting that research directed at the prophylactic use of anti-PMN agents might someday prove effective in reducing the incidence of MI and stroke.

Relation of serum elastin peptide concentration to age, FEV1, smoking habits, alcohol consumption, and protease inhibitor phenotype: an epidemiological study in working men

BACKGROUND

In clinical investigations elastin peptide concentration has been proposed as one potential marker of lung elastin degradation. No epidemiological study has yet confirmed this hypothesis.

METHODS

The relation of elastin peptide concentration to some factors closely related to pulmonary emphysema (age, smoking habits, FEV1 alpha protease inhibitor (PI) phenotype) and to alcohol consumption was examined in an epidemiological study of 310 working men. The elastin peptides used for obtaining antibodies and as reference in an ELISA assay were prepared from chemically hydrolysed elastin.

RESULTS

The elastin peptide concentration significantly decreased with age from 2.92 (1.54) micrograms/ml among subjects younger than 30 years to 2.18 (1.14) micrograms/ml among subjects older than 50. Elastin peptide concentration did not differ with smoking habits and was clearly unrelated to FEV1. A lower elastin peptide concentration was observed in all groups of subjects with a protease inhibitor phenotype other than PI MM (PI FM, IM, MP, MS, MZ, and S phenotypes).

CONCLUSIONS

The results cast doubts on the usefulness of the elastin peptide concentration as a marker of lung destruction in middle aged, predominantly healthy men. Blood elastin peptide concentration may reflect both elastin degradation and resynthesis. The results of this analysis suggest that several factors (age, alcohol consumption, non-PI MM phenotype) may be associated with decreased resynthesis of lung elastin. Further studies, conducted in various age groups and including estimates of the degree of lung destruction, are needed to unravel the mechanisms underlying lysis and resynthesis of lung elastin.