Vitamin D may reduce liver damage

Chronic liver diseases (CKD) affect about 1.5 billion people worldwide. This progressive and often asymptomatic condition can lead to dangerous complications, including cirrhosis and liver cancer. To date, liver transplantation remains the main method of treating advanced forms.

Led by Professor Hee-John Kwon from the College of Veterinary Medicine, a team of scientists has found that vitamin D can reduce inflammation and liver fibrosis by activating a specific gene, TXNIP (thioredoxin—interagating protein), an important regulator of oxidative stress and inflammation in bile duct cells (cholangiocytes).

One of the early signs of liver damage is a ductal reaction — an active proliferation of bile duct cells in response to inflammation or injury. Although initially it serves as a protective function, with chronic exposure it becomes a source of inflammation, activates immune cells and leads to fibrosis — the replacement of liver tissue with scar tissue.

Scientists have found that in patients with chronic liver diseases, lower levels of vitamin D in the blood are associated with a more pronounced ductal reaction. Mechanistic studies in mice and in cell cultures have confirmed that vitamin D increases the activity of the TXNIP gene, which, in turn, limits the overreaction of bile duct cells and inhibits inflammatory processes in the liver.

In the absence of the TXNIP gene, the opposite occurred in cholangiocytes: the release of pro—inflammatory molecules that activate Kupffer cells (liver macrophages) and liver stellate cells, the main participants in fibrosis, increased. This begins the path to inflammation and collagen formation, which worsens the condition of the liver.

“Our data indicate that the use of vitamin D for TXNIP” may be a potential target for CKD therapy. This is not just prevention, but a real intervention into the mechanism of the disease,” says Professor Kwon.

Although the study was conducted primarily in animal models and in vitro, its results provide a solid foundation for clinical research. If the effects are confirmed in humans, vitamin D may become a safe and cheap supportive therapy for patients with chronic liver disease.

In an environment where access to expensive treatments is limited, especially in low-income countries, such a solution can significantly improve the quality of life of millions of people.