Effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the PI3K-Akt-eNOS signal pathway.
Endothelial cells are very sensitive to microgravity and the morphological and functional changes in endothelial cells are believed to be at the basis of weightlessness-induced cardiovascular deconditioning. It has been shown that the proliferation, migration, and morphological differentiation of en...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2012-01-01
|
| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC3396652?pdf=render |
| _version_ | 1819024643069050880 |
|---|---|
| author | Fei Shi Yong-Chun Wang Tian-Zhi Zhao Shu Zhang Ting-Yuan Du Chang-Bin Yang Ying-Hui Li Xi-Qing Sun |
| author_facet | Fei Shi Yong-Chun Wang Tian-Zhi Zhao Shu Zhang Ting-Yuan Du Chang-Bin Yang Ying-Hui Li Xi-Qing Sun |
| author_sort | Fei Shi |
| collection | DOAJ |
| description | Endothelial cells are very sensitive to microgravity and the morphological and functional changes in endothelial cells are believed to be at the basis of weightlessness-induced cardiovascular deconditioning. It has been shown that the proliferation, migration, and morphological differentiation of endothelial cells play critical roles in angiogenesis. However, the influence of microgravity on the ability of endothelial cells to foster angiogenesis remains to be explored in detail. In the present study, we used a clinostat to simulate microgravity, and we observed tube formation, migration, and expression of endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVEC-C). Specific inhibitors of eNOS and phosphoinositide 3-kinase (PI3K) were added to the culture medium and gravity-induced changes in the pathways that mediate angiogenesis were investigated. After 24 h of exposure to simulated microgravity, HUVEC-C tube formation and migration were significantly promoted.This was reversed by co-incubation with the specific inhibitor of N-nitro-L-arginine methyl ester hydrochloride (eNOS). Immunofluorescence assay, RT-PCR, and Western blot analysis demonstrated that eNOS expression in the HUVEC-C was significantly elevated after simulated microgravity exhibition. Ultrastructure observation via transmission electron microscope showed the number of caveolae organelles in the membrane of HUVEC-C to be significantly reduced. This was correlated with enhanced eNOS activity. Western blot analysis then showed that phosphorylation of eNOS and serine/threonine kinase (Akt) were both up-regulated after exposure to simulated microgravity. However, the specific inhibitor of PI3K not only significantly downregulated the expression of phosphorylated Akt, but also downregulated the phosphorylation of eNOS. This suggested that the PI3K-Akt signal pathway might participate in modulating the activity of eNOS. In conclusion, the present study indicates that 24 h of exposure to simulated microgravity promote angiogenesis among HUVEC-C and that this process is mediated through the PI3K-Akt-eNOS signal pathway. |
| first_indexed | 2024-12-21T04:58:02Z |
| format | Article |
| id | doaj.art-4f21c200c8bd4f6eb29c9fa38a2e7080 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-21T04:58:02Z |
| publishDate | 2012-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-4f21c200c8bd4f6eb29c9fa38a2e70802022-12-21T19:15:18ZengPublic Library of Science (PLoS)PLoS ONE1932-62032012-01-0177e4036510.1371/journal.pone.0040365Effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the PI3K-Akt-eNOS signal pathway.Fei ShiYong-Chun WangTian-Zhi ZhaoShu ZhangTing-Yuan DuChang-Bin YangYing-Hui LiXi-Qing SunEndothelial cells are very sensitive to microgravity and the morphological and functional changes in endothelial cells are believed to be at the basis of weightlessness-induced cardiovascular deconditioning. It has been shown that the proliferation, migration, and morphological differentiation of endothelial cells play critical roles in angiogenesis. However, the influence of microgravity on the ability of endothelial cells to foster angiogenesis remains to be explored in detail. In the present study, we used a clinostat to simulate microgravity, and we observed tube formation, migration, and expression of endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVEC-C). Specific inhibitors of eNOS and phosphoinositide 3-kinase (PI3K) were added to the culture medium and gravity-induced changes in the pathways that mediate angiogenesis were investigated. After 24 h of exposure to simulated microgravity, HUVEC-C tube formation and migration were significantly promoted.This was reversed by co-incubation with the specific inhibitor of N-nitro-L-arginine methyl ester hydrochloride (eNOS). Immunofluorescence assay, RT-PCR, and Western blot analysis demonstrated that eNOS expression in the HUVEC-C was significantly elevated after simulated microgravity exhibition. Ultrastructure observation via transmission electron microscope showed the number of caveolae organelles in the membrane of HUVEC-C to be significantly reduced. This was correlated with enhanced eNOS activity. Western blot analysis then showed that phosphorylation of eNOS and serine/threonine kinase (Akt) were both up-regulated after exposure to simulated microgravity. However, the specific inhibitor of PI3K not only significantly downregulated the expression of phosphorylated Akt, but also downregulated the phosphorylation of eNOS. This suggested that the PI3K-Akt signal pathway might participate in modulating the activity of eNOS. In conclusion, the present study indicates that 24 h of exposure to simulated microgravity promote angiogenesis among HUVEC-C and that this process is mediated through the PI3K-Akt-eNOS signal pathway.http://europepmc.org/articles/PMC3396652?pdf=render |
| spellingShingle | Fei Shi Yong-Chun Wang Tian-Zhi Zhao Shu Zhang Ting-Yuan Du Chang-Bin Yang Ying-Hui Li Xi-Qing Sun Effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the PI3K-Akt-eNOS signal pathway. PLoS ONE |
| title | Effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the PI3K-Akt-eNOS signal pathway. |
| title_full | Effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the PI3K-Akt-eNOS signal pathway. |
| title_fullStr | Effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the PI3K-Akt-eNOS signal pathway. |
| title_full_unstemmed | Effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the PI3K-Akt-eNOS signal pathway. |
| title_short | Effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the PI3K-Akt-eNOS signal pathway. |
| title_sort | effects of simulated microgravity on human umbilical vein endothelial cell angiogenesis and role of the pi3k akt enos signal pathway |
| url | http://europepmc.org/articles/PMC3396652?pdf=render |
| work_keys_str_mv | AT feishi effectsofsimulatedmicrogravityonhumanumbilicalveinendothelialcellangiogenesisandroleofthepi3kaktenossignalpathway AT yongchunwang effectsofsimulatedmicrogravityonhumanumbilicalveinendothelialcellangiogenesisandroleofthepi3kaktenossignalpathway AT tianzhizhao effectsofsimulatedmicrogravityonhumanumbilicalveinendothelialcellangiogenesisandroleofthepi3kaktenossignalpathway AT shuzhang effectsofsimulatedmicrogravityonhumanumbilicalveinendothelialcellangiogenesisandroleofthepi3kaktenossignalpathway AT tingyuandu effectsofsimulatedmicrogravityonhumanumbilicalveinendothelialcellangiogenesisandroleofthepi3kaktenossignalpathway AT changbinyang effectsofsimulatedmicrogravityonhumanumbilicalveinendothelialcellangiogenesisandroleofthepi3kaktenossignalpathway AT yinghuili effectsofsimulatedmicrogravityonhumanumbilicalveinendothelialcellangiogenesisandroleofthepi3kaktenossignalpathway AT xiqingsun effectsofsimulatedmicrogravityonhumanumbilicalveinendothelialcellangiogenesisandroleofthepi3kaktenossignalpathway |