A new potential treatment pathway for cardiovascular disease

A collaborative study involving scientists from the University of Leicester has shown, for the first time, that a protein expressed in a subset of immune cells contributes towards the build-up of fatty deposits in arteries, which leads to cardiovascular disease. These fatty deposits are caused by macrophages, a subset of immune cells known to take up surplus cholesterol. When this is present in excess, they mature into larger cholesterol-laden cells known as foam cells which accumulate and cause blockages inside arteries.

The study, which involved collaborations in the UK, Hungary and USA, was published in Science Advances. It shows for the first time that levels of a protein called Tribbles-1 (TRIB1)* inside macrophages controls the amount of cholesterol taken up by foam cells.

The research shows that higher levels of TRIB1 increased specific cholesterol uptake receptors, thereby promoting arterial disease, whereas decreasing TRIB1 reduced disease via the same mechanism. The findings of this early translational study suggest that inhibiting TRIB1 in macrophages could be a viable therapeutic target in treating cardiovascular disease for the first time.

Researchers have long been trying to identify the proteins regulated by TRIB1 to understand their effects, and whether they are of benefit, or detrimental to disease development. The role of TRIB1 in macrophages has remained elusive for some time; this research provides the missing link and highlights the importance of cell-specific expression in cardiovascular disease.

Professor Endre Kiss-Toth from the University of Sheffield, who led the study, said: “Studying the genetics of cardiovascular disease in large human populations has revealed that TRIB1 contributes to its development.  However, this is the first time that its role in immune cells has been directly addressed, thus uncovering a new mechanism by which arterial disease develops.

“The research into this mechanism has not yet translated into novel medical interventions. However we now have pre-clinical proof that it would be beneficial to build on this research and see which patients with cardiovascular disease would benefit from the development of treatments to manage their lipid-laden foam cell formation”

Professor Alison Goodall from the University of Leicester’s Department of Cardiovascular Sciences said: “We were delighted to be able to provide Professor Kiss-Toth with the data from our large cohorts of human subjects, to demonstrate the links between TRIB1 and cholesterol uptake in humans”.

• Johnston et al: Myeloid Tribbles 1 induces early atherosclerosis via enhanced foam cell expansion doi:10.1126/sciadv.aax9183

* Tribbles-1 takes its name from the Drosophila gene tribbles which causes over-proliferation of mesodermal cells. The fruit fly gene takes its name, of course, from Star Trek.