Get enough sleep and avoid the risk of cardiovascular disease

Boston: Sleeping enough can help protect against cardiovascular disease by preventing plaque build up in the arteries, a study revealed. The research. published in the journal Nature, describes the mechanism by which insufficient sleep increases the production of inflammatory white blood cells that are known to contribute significantly to atherosclerosis.

"We found that sleep helped regulate the production of inflammatory bone marrow cells and blood vessel health, and that, conversely, sleep disturbances altered the control of inflammatory cell production, resulting in more sleep." inflammation and heart disease, "said Filip Swirski, Mbadachusetts General Hospital (MGH) in the United States.

"We have also identified how a hormone in the brain known to control arousal controls the processes in the bone marrow and protects against cardiovascular disease," Swirski said.

In order to determine to what extent insufficient sleep increases atherosclerosis, the Swirski team has submitted genetically programmed mice to develop atherosclerosis at repeated interruptions in their sleep, similar to those experienced by patients with atherosclerosis. people constantly waking up because of noise or discomfort.

Although there was no change in weight, cholesterol level, or glucose tolerance in sleep-deprived mice, compared to animals of the same strain allowed to sleep normally, those that were Subjects with sleep fragmentation developed larger arterial plaques and exhibited higher levels of monocytes and neutrophils – the inflammatory cells that contribute to atherosclerosis – in their blood vessels.

Other experiments have revealed that bone marrow production of stem cells producing white blood cells is doubled in sleep-deprived mice. A hormone called hypocretin, produced in the brain structure called hypothalamus and known to play a role in the regulation of sleep, plays an unexpected role in controlling the production of white blood cells.

Although normally produced at high levels when animals, including humans, are awake, hypocretin levels were significantly reduced in sleep-deprived mice. The team found that hypocretin regulates white blood cell production through interaction with neutrophil progenitors in the bone marrow.

They discovered that neutrophils induced monocyte production by releasing a factor called CSF-1, and experiments on mice lacking the hypocretin gene revealed that this hormone controlled the expression of CSF-1. , the production of monocytes and the development of arterial plaques.

In sleep-deprived animals, the decline in hypocretin resulted in increased production of CSF-1 by neutrophils, elevated monocyte production, and accelerated atherosclerosis. "This is a direct demonstration of the fact that hypocretin is also an important inflammatory mediator," Swirski said.

"We must now study this pathway in humans, explore other mechanisms that allow sleep to preserve vascular health and further explore this newly identified neuro-immune axis," he said.