Scientists uncover liver disease's hidden cause - breakthrough treatment nears reality

New Research Links Harmful Gut Bacteria to Rising Liver Cancer Cases

Recent scientific findings have highlighted a worrying connection between harmful gut bacteria and the increasing number of liver cancer cases. While many people associate liver disease with excessive alcohol consumption, experts now emphasize that factors such as poor diet and high fat levels in the liver can significantly increase the risk of developing the condition.

According to the British Liver Trust, liver disease is the only major illness experiencing a continuous rise in death rates, with numbers quadrupling over the past 50 years. This alarming trend has prompted researchers to explore new approaches to treating metabolic diseases like fatty liver disease.

Canadian scientists have made a breakthrough in understanding how gut bacteria contribute to liver damage and elevated blood sugar levels. Their study, published in the journal Cell Metabolism, identified a molecule produced by gut bacteria that prompts the liver to generate excess sugar and fat. This discovery could lead to innovative treatments for individuals at high risk, particularly those who are obese.

Professor Jonathan Schetzer, a biomedical sciences expert at McMaster University and lead author of the study, explained that this research offers a completely new perspective on treating metabolic disorders. Instead of targeting hormones or the liver directly, the approach focuses on intercepting a microbial fuel source before it causes harm.

He noted that the concept of the Cori cycle—where muscles and the liver exchange lactate and glucose—has been known for nearly a century. However, the team discovered a new branch of this cycle involving gut bacteria. This finding opens up new possibilities for addressing liver-related conditions.

In their research, the scientists examined D-lactate, a lesser-known molecule that plays a role in the body. They found that obese individuals tend to have higher levels of D-lactate, which originates from gut microbes. This molecule was shown to raise blood sugar levels and liver fat more dramatically than the commonly known L-lactate.

To counteract this effect, the researchers developed a "gut substrate trap" designed to bind to D-lactate in the gut and prevent its absorption. Experiments on mice revealed that those fed the trap experienced lower blood glucose levels, improved insulin resistance, and reduced liver inflammation and fibrosis compared to those not given the trap. Notably, these improvements occurred without changes to diet or weight.

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, affects approximately one in five people in the UK. The condition results from fat accumulation in the liver, leading to inflammation. Over time, this can cause scarring and eventually cirrhosis, potentially resulting in liver failure or cancer. Obese individuals and those with type 2 diabetes are at higher risk.

The Liver Trust reported 11,000 deaths from liver disease last year, many of which could have been prevented through early intervention and lifestyle adjustments. Professor Philip Newsome, Director of the Roger Williams Institute of Liver Studies at King's College London, emphasized that MASLD often goes unnoticed until it reaches an advanced stage. He warned against the misconception that only alcohol can cause liver scarring, noting that excess fat and uncontrolled blood sugar levels can lead to similar outcomes.

Although MASLD typically does not cause symptoms, some patients may experience fatigue, malaise, or discomfort in the upper right abdomen. Early detection is crucial, as the condition is often diagnosed during tests for unrelated health issues.

In response to the growing obesity crisis, the UK has taken urgent steps to address the issue. Recent data shows that nearly two-thirds of adults in England are overweight, with 260,000 more people entering this category last year. Over 26.5% of the population, or 14 million people, are classified as obese.

Last month, general practitioners were permitted to prescribe weight loss injections, known as GLP-1s, to help tackle the crisis. An estimated 1.5 million people are currently using these treatments through the NHS or private clinics, with millions more eligible for them.