HDL cholesterol (commonly referred to as “good cholesterol”) picks up excess cholesterol in the bloodstream and carries it to the liver, where it can be safely broken down.
Unlike LDL cholesterol (popularly known as “bad cholesterol”), which can form clumps capable of blocking blood vessels, HDL cholesterol can help prevent heart disease. New research now reveals a possible hitherto unknown link of this cholesterol with the level of inflammation of the liver.
A team that includes, but is not limited to, Gwendalyn J. Randolph and Emily Onufer, from Washington University in St. Louis, Missouri, United States, as well as Yong-Hyun Han, now at Kangwon National University in South Korea, has found quite convincing evidence that a type of good cholesterol is involved in a protective mechanism in the liver that prevents liver damage. This type of HDL cholesterol, specifically HDL3, appears to protect the liver by blocking inflammatory signals produced by common gut bacteria.
In experiments with rats, the researchers found that when HDL3 cholesterol is produced by the intestine, it blocks intestinal bacterial signals that cause inflammation of the liver. If not blocked, these bacterial signals travel from the intestine to the liver, where they activate immune cells that trigger an inflammatory state, which if it persists long enough ends up causing liver damage.
Yong-Hyun Han (left) and Emily Onufer from the investigation team. (Photo: Brad W. Warner)
In other words, so-called good cholesterol may be even better than we think.
The study is titled “Enterically derived high-density lipoprotein restrains liver injury via the portal vein.” And it has been published in the academic journal Science. (Source: NCYT from Amazings)