Could bone-like particles in blood contribute to artery clogging?


Islamabad, APRIL 29 , (Online): Scientists have discovered that blood circulating around the body contains bone-like particles. They found the particles in blood samples from healthy humans and rats.
They suggest that the bone-like particles could be evidence of ossification in bone marrowvessels.
The team also proposes that the particles may contribute to conditions such as atherosclerosis, a process that causes plaques, or deposits of fats and other substances, to build up inside arteries.
A recent paper in the journal Microcirculation gives a detailed account of the study.
Although most of the bone-like particles were very small, a significant proportion were large enough “to block small blood vessels throughout the vascular tree,” write the authors.
The study follows previous research that uncovered a process in bone marrow whereby blood vessels “progressively and theoretically convert into bone tissue with advancing age.”
That finding was the work of Rhonda D. Prisby, Ph.D., an associate professor of kinesiology at the University of Texas at Arlington, who is also the lead and corresponding author of the new study.
Bone-like particles and vascular calcification
Prisby wondered if the processes of ossification in bone marrow blood vessels could give rise to bone-like particles that are capable of entering the bloodstream.
“By examining seemingly unrelated images and linking the details of them together,” says Prisby, “I was able to posit the presence of bone-like particles in the blood.”
They also “sought to confirm, characterize, and quantify the presence of [bone-like particles] in peripheral whole blood samples from humans and rats.”
Cardiovascular diseases are the leading cause of death worldwide and were responsible for around 31% of all global deaths in 2016, according to the World Health Organization (WHO).
The WHO also estimate that, in 2016, 17.9 million people died of cardiovascular diseases, the majority of them from heart attack andstroke.
Vascular calcification is a complex and dynamic process — involving several mechanisms — that deposits calcium in the walls of blood vessels.
The process hardens the vessels, reduces their elasticity, and raises the risk of cardiovascular diseases and deaths from such diseases.
Probing the process of vascular calcification
In their study paper, Prisby and colleagues explain that the processes of vascular calcification are unclear. However, scientists suspect that the processes involve several types of cell in the vessel wall and the tissue that surrounds it.
The authors give an example involving smooth muscle cells. These cells in the vessel wall can transition from a contractile type to a bone-generating type and thence to a form that is “noncontractile, migratory, and proliferative.”