Analysis of the Effect of Microgravity Conditions on the Proteome of Microparticles Isolated by HUVEC Endothelial Cells

Abstract

The endothelial monolayer of the inner surface of blood vessels plays a fundamental role in maintaining the integrity of the vascular system and tissue homeostasis by regulating local blood flow and other physiological processes. Endothelial cells are very sensitive to mechanical stress, including gravitational stimuli. Given the involvement of the endothelium in the regulation of the state and functions of blood vessels undergoing changes during space flight, it is extremely important to study the mechanisms of the response of endothelial cells, including at the level of microparticles they secrete to microgravity conditions. The proteome of human umbilical vein endothelial cell microparticles (HUVEC) cultured under static conditions and while modeling the effects of microgravity using a random positioning machine has been studied by chromatography-mass spectrometry using a system consisting of an Agilent 1100 chromatograph and an LTQ-FT Ultra hybrid mass spectrometer. It has been revealed that cells under the influence of microgravity conditions secrete microparticles containing focal adhesion proteins, adapter proteins, and proteins involved in the organization of the cytoskeleton. In general, the percentage of proteins in samples cultured using a random positioning machine is higher for processes related to proinflammatory activation and immunity as well as signaling to the cytoskeleton. Based on these data, it can be assumed that, under microgravity conditions, a proinflammatory response develops and focal contacts are destroyed, which together is a prerequisite for the development of endothelial dysfunction.