The Bacterial Connection to Alcoholism and Liver Disease

The Bacterial Connection to Alcoholism and Liver Disease

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About 100 trillion bacteria live inside your digestive system, and each strain of bacteria has both good and bad effects. Researchers are now looking more closely at how this system of organisms in your gut influence several health conditions ranging from heart disease and cancer to arthritis and liver disease (Harvard Health, 2016). More specifically, a research team led by Dr. Bernd Schnabl at the University of California, San Diego, explored how gut microbes contribute to alcoholic hepatitis, a life-threatening form of alcohol-associated liver disease (AALD) caused by heavy drinking over time (National Institutes of Health, 2019). To understand this study, let’s first take a look at the facts on AALD, the signs of alcoholic hepatitis, and how your gut has more power than you realize.

Quick Facts on AALD 

Excessive intake of alcohol causes AALD; however, in the early stages of the disease, liver damage may be reversed if the person stops drinking. It’s important to understand this fact, especially if you or someone you love has an alcohol use disorder. Intervention and addiction treatment can literally save a person’s life. To comprehend the long-term ramifications of this disease, and break-down AALD even further, the American National Liver Foundation (ANLF) offers information on the three types of liver disease that can occur from heavy drinking:

  • Fatty liver – an excessive build-up of fat in the liver, almost all heavy drinkers develop a fatty liver.
  • Alcoholic hepatitis – a form of alcohol-associated liver disease (AALD) when the liver cells become inflamed. 
  • Alcohol-related cirrhosis – in which normal liver tissue is replaced by non-living scar tissue. 

Up to 35% of heavy drinkers develop alcoholic hepatitis, and between 10 and 20 percent develop cirrhosis. The damage from alcohol-related cirrhosis is not reversible and can cause liver failure. Additionally, alcohol remains the second most common cause of liver cirrhosis after hepatitis C virus infection in the U.S., contributing to around 25 percent of cases of liver cirrhosis, states ANLF.

Signs of Alcoholic Hepatitis 

Symptoms of alcoholic hepatitis include inflammation of the liver, jaundice (skin yellowing), and, if not treated, ultimately liver failure and death. As treatment for alcoholic hepatitis is limited, liver transplantation is the only cure. In severe cases, more than half of patients die within two months of diagnosis. Other signs and symptoms of the disease include:

  • Loss of appetite
  • Nausea and vomiting
  • Fatigue and weakness
  • Abdominal tenderness
  • Low-grade fever (Mayo Clinic)

In previous research, scientists have shown that microbes living in the gut can influence AALD, however, the actual link between AALD and gut bacteria is still a mystery – until now. A research team led by Dr. Bernd Schnabl at UC San Diego explored how gut microbes actually contribute to alcoholic hepatitis.

How Gut Bacteria Can Treat Alcohol Hepatitis

The research team first analyzed bacteria in fecal samples from patients with alcohol use disorder (AUD) and alcoholic hepatitis. A large portion (80 percent) of samples from people with alcoholic hepatitis contained several thousand Enterococcus faecalis, a common gut bacterium, then samples from healthy drinkers. Additionally, researchers also discovered cytolysin (a cell-destroying toxin secreted by specific E. faecalis) in fecal samples from 30 percent of the people with alcoholic hepatitis. Upon further inspection, the team also found:

  • People carrying toxin-producing strains of E. faecalis had more severe alcoholic hepatitis and a greater risk of death. 
  • Among those with cytolysin-positive E. faecalis, 89 percent died within 180 days of admission, compared with only 3.8 percent of people with cytolysin-negative E. faecalis (NIH).

Researchers then studied mice that had been injected with feces from people with alcoholic hepatitis. They found that transplantation of feces with cytolysin-positive E. faecalis caused more severe liver disease in mice than feces without it. Next, the team investigated the therapeutic potential of bacteriophages – viruses that destroy bacteria. Instead of using antibiotics that kill many types of bacteria, researchers identified four bacteriophages in sewage water that target cytolytic E. faecalis. Scientists then transplanted stool from cytolysin-positive alcoholic hepatitis patients into mice designed to model AALD. 

The mice were then treated with bacteriophages targeting the cytolytic E. faecalis strains. The result? The mice with these viruses had less liver injury, inflammation, and significantly reduced levels of cytolysin in the liver compared to controls. These results suggest that cytolytic E. faecalis causes more severe alcoholic hepatitis and that bacteriophages might be used to target these bacteria to treat AALD. 

The Promise of a Better Future

Researchers hope to conduct more clinical trials to see how humans respond to the same treatment and to see whether this new therapeutic approach is useful for patients with alcoholic hepatitis. If you or someone you know is suffering from an alcohol use disorder, get help now.  Liver damage may be reversed if the person stops drinking, so early intervention is crucial. At Silver Lining, we have formed a highly skilled multi-disciplinary treatment team to deliver exceptional client care for alcohol or drug addiction. We take a conventional and holistic approach when it comes to treating addiction. Our motto says it all: Courage – Growth – Recovery. Call Silver Lining Recovery at 1-833-8GROWTH today.