RESUMO
The effects of HIF1A knockdown by RNA interference on the histone H3K9 methylation in human umbilical cord mesenchymal stromal cells in vitro under conditions of 24-h exposure to hypoxia (1% O2) were studied. Evaluation of transcriptional activity of genes involved in the regulation of H3K9 methylation (KDM3A, KDM4A, and EHMT2) and the cytofluorimetric analysis of the expression of the corresponding antigens and H3K9 methylation level demonstrated a pronounced stimulating effect of hypoxic exposure. Moreover, the expression of KDM4A and EHMT2 was regulated by HIF1A-mediated mechanism, unlike KDM3A; the level of the corresponding proteins depended on HIF1A. In addition, the HIF-1-dependent regulation of KDM3A, KDM4A, and EHMT2/G9a, and directly the H3K9 methylation level in mesenchymal stromal cells also took place under normoxia conditions.
Assuntos
Hipóxia Celular , Histonas , Subunidade alfa do Fator 1 Induzível por Hipóxia , Histona Desmetilases com o Domínio Jumonji , Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Humanos , Histonas/metabolismo , Histonas/genética , Metilação , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia Celular/genética , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Interferência de RNA , Cordão Umbilical/citologia , Cordão Umbilical/metabolismo , Células Cultivadas , Técnicas de Silenciamento de Genes , Regulação da Expressão GênicaRESUMO
The dynamics of the expression of genes encoding adhesion molecules, molecules of the connective tissue matrix, and its remodeling enzymes was studied in multipotent mesenchymal stromal cells (MSCs) from human adipose tissue after interaction with cord blood hematopoietic progenitors (HSPCs). An upregulation of ICAM1 and VCAM1, directly proportional to the coculture time (24-72 h), was found. After 72 h of culturing, a downregulation of the genes encoding the majority of matrix molecules (SPP1; COL6A2,7A1; MMP1,3; TIMP1,3; and HAS1) and cell-matrix adhesion molecules (ITGs) was revealed. The detected changes may ensure the realization of the stromal MSC function due to improvement of adhesion and transmigration of HSPCs into the subcellular space.
Assuntos
Moléculas de Adesão Celular/metabolismo , Comunicação Celular , Matriz Extracelular/genética , Sangue Fetal/citologia , Regulação da Expressão Gênica , Hematopoese , Células-Tronco Mesenquimais/citologia , HumanosRESUMO
The expression of several genes which functions are associated with cellular senescence was analyzed in multipotent mesenchymal stromal cells during long-term cultivation at different oxygen levels (20, 5, and 1%) using the RT² Profiler™ PCR Array Human Cellular Senescence system (Qiagen, United States). It was established that replicative senescence processes develop most actively in the cells cultured under the standard conditions (20% O2). The most significant changes were observed in the expression of CCND1, ID1, IGF1, PIK3CA, and SERPINE1 genes.