Bone-Like Hydroxyapatite Formation in Human Blood
International Journal of Environmental and Science Education
Titov Anatoly T.
Larionov Peter M.
Ivanova Alexandra S.
Zaikovskii Vladimir I.
Chernyavskiy Mikhail A.
Novosibirsk State University, Novosibirsk, RUSSIA
Novosibirsk Research Institute of the Pathology of Blood Circulation named after academician E.N. Meshalkin, Novosibirsk, RUSSIA
Russian Foundation for Basic Research
The purpose of this study was to prove the mechanism of mineralization, when
hydroxyapatite (HAP) is formed in blood plasma. These observations were substantiated by
in vitro simulation of HAP crystallization in the plasma of healthy adults in a controllable
quasi-physiological environment (T = 37°C, pH = 7.4) and at concentrations of dissolved Ca
and P ions that resemble those in the blood of healthy adults. Another objective of the
study was to investigate the role of Mg2+, Na+Cl - and serum albumin, the main blood
protein, in the formation of calcium phosphate. Mineralized aortic and mitral valves of the
heart were obtained in operations on patients with rheumatic or septic acquired valvular
disease. Macroscopic and histological analyses of these samples were conducted. Primary
nanocrystals of HAP formed in the blood may take part in the mineralization of both cardiac
valves and vessels. The penetration of HAP nanocrystals may be caused by breaks in the
endothelium of blood vessels. The lowering of pH may result from substantial degradation
in the valve tissue. The experimental data make it possible to conclude that albumin and
Fetuin-A are structural proteins that are responsible for subsequent incorporation of HAP
nanocrystals in newly formed bone tissue