Potentially Damaging Ossified Particles Discovered in the Aging Bloodstream
Calcification is the inappropriate deposition of minerals into tissue, altering structural properties to cause a loss of elasticity. It is a feature of the aging cardiovascular system, in part caused by inflammatory signals and other harmful activities of senescent cells. The growing numbers of senescent cells in old tissues cause changes in the behavior of other cell populations, which leads to greater mineralization of tissues that should normally be flexible. Researchers here uncover another consequence of this process, which is the presence of what are effectively bone particles in the bloodstream. These particles are large enough to cause a variety of damage to blood vessels, and while the size of this effect is unknown, this adds to the existing set very good reasons to try to prevent and reverse calcification in aging tissues.
Blood vessels within bone marrow may progressively convert into bone with advancing age. Examination of these vessels led to the discovery of bone-like particles in the peripheral circulation. The findings suggest that ossified particles may contribute to diseases such as vascular calcification, heart attack, stroke, and inadequate blood supply to the limbs. In fact, some of the ossified particles are large enough to clog the smallest blood vessels in the vascular tree.
Approximately 610,000 people die each year from a heart disease-related event, making it the leading cause of death for both men and women in the United States, according to the Centers for Disease Control and Prevention. Vascular calcification is a common characteristic and risk factor for morbidity and mortality. These bone-like particles are potentially more dangerous because of their sharp edges. "Some of the ossified particles have sharp tips and edges that could damage the lining of blood vessels. This damage could initiate events leading to atherosclerosis, which can restrict blood flow over time. When looking for etiologies related to vascular calcification, heart attack and/or stroke, perhaps we should consider if and how ossified particles contribute to these diseases. We will examine these possibilities."
Link: https://www.uta.edu/news/news-releases/2019/08/19/bone-particles-in-blood
Average diameter of erythrocote is 6.2 to 8.2 uM, so say 7.2uM.
There is a wide range of diameters of brain arterioles -5 to 100uM, though they vary in diameter with smooth muscle contraction/relaxation in their walls.
After the arterioles come capillaries which are 5-10uM in diameter ie quite narrow.
Judging from the photograph in the article, the calcium particles appear to exceed an erythrocyte in diameter by circa 1.5x and in length by up to 4x. - ie 10.8uM by 28.8uM - so easily able to become lodged in the microcirculation of any tissue,eg of brain.
Trans doppler ultrasound often picks up evidence of micro stroke which individually would be insignificant but which,collectively, could account for cognitive impairment. This is particularly so in those patients known to have atherosclerosis.
Hmmm... I sorta wonder if a few months in zero gee, flushing out a lot of calcium, might actually be good for people with unwanted calcification...