Fatty liver disease starts with a damaged membrane layer
Millions of people have a fatty liver without knowing it. When that fatty liver tips into dangerous inflammation, the trigger has long been unclear. New research points to a specific form of damage deep inside the liver cell.
Cardiolipin is a fat molecule found exclusively in the inner membrane of mitochondria (the cell’s energy factories). It keeps the structure intact that mitochondria need to produce energy. Without enough cardiolipin, that structure breaks down, with serious consequences.
From fatty liver to severe inflammation
The study, published in eLife, showed that cardiolipin is reduced in humans and mice with fatty liver disease (MASLD) and in people with metabolic-dysfunction-associated steatohepatitis (MASH). To test causation, the researchers deleted the cardiolipin-synthesis gene specifically in the liver cells of mice. Those mice developed spontaneous, severe liver inflammation with fibrosis, without any special diet or additional intervention.
The mechanism worked as follows. Loss of cardiolipin paradoxically increased mitochondrial respiratory capacity but also promoted electron leakage at specific sites in the electron transport chain (the system mitochondria use to convert energy). That leakage produced reactive oxygen species, which drove oxidative stress and inflammation in liver cells.
A new therapeutic target
This matters because MASH is one of the fastest-growing causes of liver disease globally, with limited treatment options. If cardiolipin plays such a central role in disease progression, restoring cardiolipin composition could become a therapeutic goal. The researchers also show that the balance of coenzyme Q (a molecule that ferries electrons) is disrupted when cardiolipin is lost.
The findings are preliminary. Mouse models show robust effects, but whether the same mechanisms operate as strongly in humans requires clinical investigation. The study does provide a concrete mechanistic model for the transition from a silent fatty liver to active liver disease.
Search terms to explore further: cardiolipin mitochondria liver disease | electron transport chain oxidative stress | MASH MASLD pathogenesis