Molecular genetic features of human mesenchymal stem cells after their osteogenic differentiation under the conditions of microgravity

Abstract

Modified gravity is known to affect both the whole body and the molecular processes in individual cells. The purpose of the present study was to examine gene expression pattern in mesenchymal stromal cells (MSCs) of human bone marrow under the conditions of microgravity. Exposure of cell cultures on dRPM for 20 days resulted in significant changes in the expression of 144 genes. Thirty of these genes increased their expression, whereas the other 114 genes decreased their expression. Analysis of the genes revealed that most of them belonged to 11 principal groups according to their biological roles in the cell. Most genes with a changed expression were from the following groups: inflammatory responses and intercellular interactions, matrix and adhesion, metabolic processes, and signaling and regulation. We found that microgravity inhibited the expression of genes encoding the products, which play a key role in osteogenic differentiation including COL15A1, CXCL12, DPT, and WISP2 and are involved in intercellular interactions between MSCs and different types of bone marrow cells such as CXCL12 and SCG2. These molecular-genetic changes indicate the possible involvement of progenitor cells of osteogenic differon in the development of osteopeny under the conditions of microgravity.