A well-known molecule, called Notch, may be behind alcohol’s protective cardiovascular effects. This finding may help scientists create a new treatment for heart disease that mimics the beneficial influence of modest alcohol consumption.
“Any understanding of a socially acceptable, modifiable activity that many people engage in, like drinking, is useful as we continue to search for new ways to improve health,” said Eileen M. Redmond, Ph.D., associate professor in the Department of Surgery, Basic and Translational Research Division, at the University of Rochester Medical. “If we can figure out at the basic science level how alcohol is beneficial it wouldn’t translate to doctors prescribing people to drink, but hopefully will lead to the development of a new therapy for the millions of people with coronary heart disease.”
The study suggests that alcohol at moderate levels of consumption inhibits Notch, and subsequently prevents the buildup of smooth muscle cells in blood vessels, which contributes to narrowing of the arteries and can lead to a heart attack or stroke.
The team studied the effects of moderate amounts of alcohol in human coronary artery smooth muscle cells and in the carotid arteries of mice. In both scenarios, regular, limited amounts of alcohol decreased Notch, which in turn decreased the production and growth of smooth muscle cells, leaving vessels open and relatively free of blockages or build-up - a desirable state for a healthy heart.
Specifically, in human smooth muscle cells, treatment with moderate levels of alcohol significantly decreased the expression of the Notch 1 receptor and inhibited Notch signaling, leading to decreased growth of smooth muscle cells. The inhibitory effect of moderate alcohol on smooth muscle cell growth was reversed if the Notch pathway was artificially switched on in these cells.
In a mouse model of vessel remodeling, daily feeding of alcohol inhibited Notch in the vessel wall and markedly reduced vessel thickening, compared to the control, no alcohol group. Vessel remodeling occurs when vessels change shape and thickness in response to different injurious stimuli.
“At the molecular level, this is the first time anyone has linked the benefits of moderate drinking on cardiovascular disease with Notch,” said researchers. “Now that we’ve identified Notch as a cell signaling pathway regulated by alcohol, we’re going to delve deeper into the nuts and bolts of the process to try to find out exactly how alcohol inhibits Notch in smooth muscle cells.”
Researchers admit that uncovering how alcohol inhibits Notch signaling in these cells will not be an easy task. According to Redmond, “The Notch pathway is complex, and there are multiple potential regulatory points whichcould be affected by alcohol.”
Source: Arteriosclerosis, Thrombosis and Vascular Biology