In older male macaque monkeys fed a high-fat diet for 18 months, higher levels of a liver enzyme called BAAT in the blood are linked to less severe liver scarring, indicating that BAAT could...
Mechanism
Synthesis from 1 study
When the liver gets too much fat over time, it makes more of a special enzyme that changes bile acids. These changed bile acids can't help clear fat well, so fat builds up, but somehow they also slow down the scarring process. This makes the liver look less damaged on tests, even though it's still...
Most probable mechanism
When the liver is overloaded with fat for a long time, it makes more of a specific enzyme that changes bile acids. These changed bile acids don't work as well at helping the liver get rid of fat, so fat builds up inside liver cells. This buildup stresses the cells and triggers inflammation, but the same enzyme change also seems to slow down the scarring process, making the liver damage look less severe on tests even though fat is still piling up.
Chronic exposure to excess dietary lipids increases hepatic bile acid flux and demand for conjugation
Bile acid-CoA: amino acid N-acyltransferase (BAAT) is upregulated to enhance conjugation of bile acids with amino acids
Altered bile acid composition disrupts farnesoid X receptor signaling, reducing expression of lipid transporters and impairing hepatic lipid export
Accumulation of lipids within hepatocytes induces cellular stress, oxidative damage, and low-grade inflammation
The modified bile acid pool suppresses activation of hepatic stellate cells and extracellular matrix deposition, resulting in reduced fibrosis despite ongoing steatosis
Less supported by current evidence, but not ruled out
Long-term high-fat intake damages the energy-producing parts of liver cells, making them less able to burn sugar for energy. At the same time, the liver starts making more sugar from scratch, raising blood sugar levels and worsening metabolic stress.
Mitochondrial enzymes critical for the tricarboxylic acid cycle are downregulated, reducing acetyl-CoA oxidation and ATP production
Pentose phosphate pathway activity increases to generate NADPH, fueling gluconeogenic flux
Impaired glucose oxidation and enhanced glucose production lead to hyperglycemia and insulin resistance
Fat overload weakens the structural support and signaling systems in heart muscle cells, reducing their ability to respond to mechanical and metabolic demands, which contributes to whole-body metabolic imbalance.
Expression of proteins that link the cell membrane to the internal skeleton is reduced in heart muscle cells
Loss of these proteins impairs mechanosensing and survival signaling pathways, including AKT and calcium regulation
Cardiac remodeling and reduced contractile efficiency increase systemic metabolic demand and inflammatory signaling
Evidence from Studies
Supporting (1)
Community contributions welcome
Contradicting (0)
Community contributions welcome
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.