A Role For Gut Bacteria in Fatty Liver Disease?

A new study in Cell Metabolism tells us that gut bacteria might play a role in the development of fatty liver disease. Jing Yuan and colleagues found that a strain of Klebsiella can cause fatty liver disease in mice. In addition, they found a correlation between the presence of these bacteria in humans and fatty liver disease.

Alcohol-Producing Klebsiella

It turns out that some strains of Klebsiella pneumoniae produce high amounts of alcohol. These are the bacteria with the link to fatty liver disease. Yuan found that up to 60 percent of a patient population with fatty liver disease also had the presence of these bacteria. Yuan wrote:

NAFLD (non-alcoholic fatty liver disease) is a very heterogeneous disease and the findings here likely represent just one type of etiology. Indeed, other mechanisms for NAFLD development, including a further role for the gut microbiota, need to be explored.

In other words, fatty liver disease can come in many forms, with different causes. This might be one of them.

Auto-Brewery Syndrome

In a fairly rare condition, patients can have microbiota that produce high amounts of alcohol from normal dietary carbohydrates. Even if they never take a drink, such patients can wind up with significant blood alcohol levels. A patient with this condition stimulated Yuan and her colleagues to look more closely at a role for Klebsiella in fatty liver disease.

A Growing Concern

Fatty liver disease is quite common. Between 30 and 40 percent of American adults have it. Nearly ten percent of children do. But most of them have simple fatty liver, with no liver damage. However, three to twelve percent develop a more serious form, steatohepatitis. It’s also known as NASH. And it’s becoming more common as a consequence of obesity. In fact, NASH will soon become the leading reason for liver transplants.

Thus, sorting out the role for gut bacteria in fatty liver disease could prove to be quite important.

Click here for the study, here and here for further reporting on it.

Bridging Liver Fibrosis, photograph by Durgesh1104 / Wikimedia Commons

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September 23, 2019