How liver disease leads to cardiovascular disease

Affecting up to 40% of the population in Southeast Asia, non-alcoholic fatty liver disease (NAFLD) is a common chronic condition characterised by the accumulation of fat in the liver. The disease can lead to the scarring of liver tissue and liver cancer.

However, the top cause of death in patients with NAFLD is cardiovascular complications, not liver disease.

To find out why this is the case, a team of researchers from NTU investigated how NAFLD and cardiovascular disease are connected.

Studying blood vessel cells cultured from samples donated by NAFLD patients and healthy controls, the researchers found that compared to healthy individuals, the cells of fatty liver disease patients contained elevated levels of proteins called chemokines.

Chemokines usually attract immune cells such as T cells to the site of infection, indicating where T cells should begin combatting the infectious agent. However, abnormally high levels of chemokines can unintentionally attract T cells into the blood vessel walls of liver disease patients, causing inflammation and damaging the blood vessels.

The researchers also detected three times as many circulating damaged endothelial cells – cells from the inner lining of blood vessels that have been shed into the bloodstream – in fatty liver disease patients, an indicator of blood vessel injury.

As a result of inflammation and blood vessel damage, NAFLD patients have a higher risk of developing blood clots and cardiovascular disease.