Together, these observations suggest that chronic alcohol consumption results in lymphopenia, which can increase homeostatic proliferation and accelerate conversion of naïve T cells into memory T cells (Cho et al. 2000). One of the most dramatic effects of both acute and chronic alcohol use is the impaired capacity of monocytes to produce cytokines that trigger inflammation, particularly TNF-α, in response to bacterial or mycobacterial infection. Of interest, Denis (1991) found that TNF-α had a beneficial effect on survival when it was infused into mice inoculated with M. Tuberculosis, suggesting that alcohol’s negative effect on the antimycobacterial activity of macrophages potentially could be overcome.
Examining how pain could play a direct protective role in the gut
Molecular mechanisms of the dose-dependent effects of alcohol on the immune system and HPA regulation remain poorly understood due to a lack of systematic studies that examine the effect of multiple doses and different time courses. There may be important differences in the effects of ethanol on the immune system depending on whether the study is conducted in vitro or in vivo, as the latter allows for a complex psychogenic component in which stress-related hormones and immune-signaling molecules interact. In addition, most studies have been done in vitro using primary cells or cell lines in the presence of rather high, constant doses of ethanol. Similarly, most rodent studies to date have focused on acute/short-term binge models utilizing high concentration of ethanol (20% ethanol) as the sole source of fluid, a possible stressor in itself. Therefore, there is a pressing need for in depth studies that examine dose-dependent effects of chronic ethanol consumption on immunity in vivo to allow for the complex interactions between ethanol, its metabolites, HPA signaling, nutritional deficiencies, and the immune system. Chronic alcohol consumption triggers an inflammatory response, contributing to various health issues.
Opposing Effects of Alcohol on the Immune System
Inflammation is the source of many serious conditions, but it’s actually your immune system’s way of healing your body after an injury or fighting an infection. When you get a cut or the flu, your body calls in an inflammatory team to handle the situation. It’s made up of different specialized forces such as cells, tissues, and organs that work together to protect your body. Gut microbiota are able to produce various of the aforementioned metabolites that act on enteroendocrine cells, the vagus nerve or by translocation throughout the gut epithelium into the systemic circulation and may have an impact on host physiology. To this end, heavy drinkers have been shown to exhibit an increase in both IgA and IgM levels when compared to both moderate and light male drinkers.
Moderate alcohol consumption ‘boosts immune system’
Additional studies in rodents assessed the effects of alcohol on the effectiveness of bacillus Calmette-Guérin (BCG) vaccination, which protects against tuberculosis. The studies found that when animals consumed ethanol before BCG vaccination, they were not protected against a subsequent pulmonary challenge with M. In contrast, mice that consumed ethanol after the BCG vaccination were protected against a subsequent M.
VDR normally reduces expression of a signaling molecule called renin angiotensin (RAS) (Li et al. 2004). Lowered RAS levels in turn induce dysregulation of the mitochondria (Kimura et al. 2005) and enhance production of reactive oxygen species (ROS) that can damage various molecules in the cells (Iuchi et al. 2003). Naïve human T cells produce low levels of VDR, but expression is increased to moderate levels in activated T cells (Irvin et al. 2000). Human T cells incubated in vitro with variable concentrations of ethanol (0, 10, 25, and 50mM for 24 hours) showed a reduced expression of the VDR, accompanied by increased expression of RAS and ROS as well as increased T-cell death (Rehman et al. 2013).
Healthy habits, such as being active, eating a balanced diet, and getting enough sleep, can keep your immune system strong. But unhealthy factors, like stress, smoking, or drinking alcohol, can be taxing for your immune system and make it harder for it to fight off infection. Alcohol feeding suppresses the production and secretion of certain acute-phase proteins (i.e., type II cell surfactant).
Several lines of evidence show that the number and function of B-cells are reduced by chronic alcohol. For example, chronic alcoholics exhibit loss of B-cells in the periphery and a reduced capacity to generate protective antibodies (Cook et al. 1996). In addition, chronic alcohol can decrease the number of B-cells that produce an antibody type called IgA5 in one of the layers of mucous membranes (i.e., the lamina propria), which is indicative of psilocybin magic mushrooms uses effects & hazards altered mucosal immunity (Lopez et al. 1994). Finally, alcohol inhibits the responsiveness of B-cells at certain developmental stages (i.e., blasts, which are the precursors to the antibody-secreting plasma cells) to various cytokines, particularly to IL-2 and IL-4. However, alcohol may have a dual effect on B-cell function because some studies have reported that B-cells also could be activated in alcohol-consuming people (Drew et al. 1984).
In chronically alcohol-fed rats, the T cells fail to proliferate adequately in response to stimulation by IL-2. The results of other investigations imply that decreased T-cell proliferation may be a consequence of the impaired function of accessory cells (e.g., antigen-presenting cells) after alcohol use. For example, the interaction of T cells with antigen-presenting monocytes or macrophages requires the presence of several proteins on the surfaces of both the T cells and the antigen-presenting cells (e.g., T-cell receptors and MHC molecules).
The production of some of these proteins also is altered in alcohol-exposed cells. Finally, reduced T-cell proliferation may be attributed to the increased production of immunoregulatory cytokines (e.g., IL-10 and TGF-β) caused by alcohol. The mechanisms by which moderate alcohol consumption might exert these beneficial effects are only beginning to emerge.
Nevertheless, studies have shown that the normal gut microbiota comprises mainly Bacteroidetes and Firmicutes as the dominant phyla, followed by Actinobacteria and Verrucomicrobia. These gut commensals play an important role in specific functions like nutrient and drug metabolism, protection against pathogens, maintenance of structural integrity of gut mucosal barrier, among others [5,6]. Alcoholics and laboratory animals chronically ingesting alcohol have lower-than-normal numbers of all subpopulations of T cells in the blood, in the thymus—the gland where T cells mature—and in the spleen, where immune reactions are initiated. The mechanism underlying the alcohol-induced decrease in T-cell numbers still is unknown. Some researchers have suggested that acute alcohol exposure induces programmed cell death, or apoptosis, in immature T cells in the thymus. Acute alcohol exposure also results in increased apoptosis of mature lymphocytes and monocytes in the blood.
- Alcohol consumption also damages epithelial cells, T cells, and neutrophils in the GI system, disrupting gut barrier function and facilitating leakage of microbes into the circulation (see the article by Hammer and colleagues).
- Acetate is then released into the blood where it is oxidized to carbon dioxide in the heart, skeletal muscle, and brain (Zakhari 2006).
- Fresh produce and nuts and seeds pack a lot of zinc, beta-carotene, vitamins A, C, and E, and other nutrients you need for a healthy body.
- Parallel to the T-cell response, the B cells mount another line of defense against the invading bacteria.
- Maintaining gut homeostasis—beneficial microbiota composition—plays a critical role in immune responses.
For certain types of infections (e.g., HIV and mycobacteria), however, the failure of an appropriate initial immune response to pathogens can have profound and potentially prolonged effects on the immune system and the drinker’s health. Although alcohol likely affects many immune system cells, macrophages and monocytes appear to be particularly sensitive to its influences. Both acute and chronic alcohol use may decrease the activation of antigen-specific T cells by inhibiting the macrophages’ capacity to present mycobacterial antigen to lymphocytes (Szabo et al. 1993). Bermudez and Young (1991) have shown that alcohol also enhances the survival of another pathogen (i.e., the Mycobacterium avium complex, or MAC2) within blood-derived macrophages in people and liver macrophages (i.e., Kupffer cells) in mice. The same study demonstrated an increase in MAC colony counts in the blood, liver, and spleen of alcohol-fed mice compared with controls, suggesting that alcohol use prior to and during MAC infection contributes to dissemination of the disease in the body. Male rats on a liquid diet with 35% of calories coming from ethanol also showed enhanced mRNA half-life and protein expression of LPS-induced TNF-α by increasing TNF-α in liver monocytes/macrophages (Kishore, McMullen et al. 2001).
To date, most studies have reported that heavy alcohol consumption directly alters the biodiversity of gut microbes and produces dramatic change in the relative abundance of some particular microbes, causing dysbiosis and inflammation in the gut [47,48,49]. Similar effects have been shown in moderate alcohol consumption and chronic consumption in animal models [46,50,51,52]. Unlike chronic alcohol consumption, binge drinking pattern (a frequent form of alcohol consumption, defined as 5 or more drinks for men and 4 or more drinks for women within 2 h) has not shown homogeneous results even using similar experimental designs. Some studies have found an effect of binge drinking on IMB (increased 16S rDNA levels) [53], but others have obtained negative results [54]; therefore, more studies are needed to elucidate this relationship.
In addition, alcohol interferes with TNF expression by inhibiting the normal processing of newly produced TNF that is necessary for normal TNF functioning (Zhao et al. 2003). If you drink every day, or almost every day, you might notice that you catch colds, flu or other alcohol use disorder symptoms and causes illnesses more frequently than people who don’t drink. That’s because alcohol can weaken your immune system, slow healing and make your body more susceptible to infection. But prolonged alcohol abuse can lead to chronic (long-term) pancreatitis, which can be severe.
Steatotic liver disease develops in about 90% of people who drink more than 1.5 to 2 ounces of alcohol per day. Heavy drinking can also lead to a host of health concerns, like brain damage, heart disease, treatment and recovery national institute on drug abuse nida cirrhosis of the liver and even certain kinds of cancer. Alcohol can have a range of harmful effects on the body, which can diminish a person’s immune response and put them more at risk for COVID-19.
Uncontrolled inflammation can do more harm than good by damaging healthy cells and tissues. The white blood cells, tissues and organs that make up our body’s immune system are designed to fight off infections, disease and toxins. Alcohol alters the composition of the IMB, resulting in an alteration of the amount and type of neuroactive substances produced by the microbiota, which may lead to behavioral alteration [79]. Gut–brain communication is disrupted by alcohol-related immune and gut dysfunction [80]. Alcohol modifies the intestinal microbiota, pH and permeability of the intestine, causing an increased entry of endotoxins into our CNS and brain, leading to neuroinflammatory processes.