TY - JOUR
T1 - Influence of rabbit notochordal cells on symptomatic intervertebral disc degeneration
T2 - anti-angiogenic capacity on human endothelial cell proliferation under hypoxia
AU - Kwon, W. K.
AU - Moon, H. J.
AU - Kwon, T. H.
AU - Park, Y. K.
AU - Kim, J. H.
N1 - Funding Information:
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology ( NRF-2013R1A1A2063968 ), and by Korea University Guro Hospital grant ( O1600171 ).
Funding Information:
HMEC-1 was kindly provided by Professor Daniel C Devor (Department of Cell Biology and Physiology, University of Pittsburgh). And we gratefully acknowledge Soon-young Hwang (Statistical assistance, Center for Medical Research support, Korea University) for her assistance and thorough advices regarding statistical analyses.
PY - 2017/10
Y1 - 2017/10
N2 - Objectives Symptomatic degenerative disc disease (DDD) is associated with neovascularization and nerve ingrowth into intervertebral discs (IVDs). Notochordal cells (NCs) are key cells that may lead to regeneration of IVDs. However, their activities under conditions of hypoxia, the real environment of IVD, are not well known. We hypothesized that NCs may inhibit neovascularization by interacting with endothelial cells (ECs) under hypoxia. Design Human IVDs were isolated and cultured to produce nucleus pulposus (NP) cell conditioned medium (NPCM). Immortalized human microvascular ECs were cultured in NPCM with notochordal cell-rich rabbit nucleus pulposus cells (rNC) under hypoxia. Vascular endothelial growth factor (VEGF), vascular cell adhesion molecule (VCAM), and interleukin-8 (IL-8) were analyzed by ELISA. Focal adhesion kinase (FAK), filamentous actin (F-actin), and platelet-derived growth factor (PDGF) were evaluated to investigate EC activity. Wound-healing migration assays were performed to examine EC migration. Results The VEGF level of EC cells cultured in NPCM was significantly higher under hypoxia compared to normoxia. VEGF expression was significantly decreased, and FAK, F-actin, PDGF expression were inhibited when ECs were cocultured with rNCs under hypoxia. ECs cocultured with rNC in NPCM showed significantly decreased migratory activity compared to those without rNC under hypoxia. Conclusions The angiogenic capacity of ECs was significantly inhibited by NCs under hypoxia via a VEGF-related pathway. Our results suggest that NCs may play a key role in the development of IVDs by inhibiting vascular growth within the disc, and this may be a promising novel therapeutic strategy for targeting vascular ingrowth in symptomatic DDD.
AB - Objectives Symptomatic degenerative disc disease (DDD) is associated with neovascularization and nerve ingrowth into intervertebral discs (IVDs). Notochordal cells (NCs) are key cells that may lead to regeneration of IVDs. However, their activities under conditions of hypoxia, the real environment of IVD, are not well known. We hypothesized that NCs may inhibit neovascularization by interacting with endothelial cells (ECs) under hypoxia. Design Human IVDs were isolated and cultured to produce nucleus pulposus (NP) cell conditioned medium (NPCM). Immortalized human microvascular ECs were cultured in NPCM with notochordal cell-rich rabbit nucleus pulposus cells (rNC) under hypoxia. Vascular endothelial growth factor (VEGF), vascular cell adhesion molecule (VCAM), and interleukin-8 (IL-8) were analyzed by ELISA. Focal adhesion kinase (FAK), filamentous actin (F-actin), and platelet-derived growth factor (PDGF) were evaluated to investigate EC activity. Wound-healing migration assays were performed to examine EC migration. Results The VEGF level of EC cells cultured in NPCM was significantly higher under hypoxia compared to normoxia. VEGF expression was significantly decreased, and FAK, F-actin, PDGF expression were inhibited when ECs were cocultured with rNCs under hypoxia. ECs cocultured with rNC in NPCM showed significantly decreased migratory activity compared to those without rNC under hypoxia. Conclusions The angiogenic capacity of ECs was significantly inhibited by NCs under hypoxia via a VEGF-related pathway. Our results suggest that NCs may play a key role in the development of IVDs by inhibiting vascular growth within the disc, and this may be a promising novel therapeutic strategy for targeting vascular ingrowth in symptomatic DDD.
KW - Angiogenesis
KW - Degenerative disc disease
KW - Endothelial cell
KW - Hypoxia
KW - Notochordal cell
KW - Nucleus pulposus
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U2 - 10.1016/j.joca.2017.06.003
DO - 10.1016/j.joca.2017.06.003
M3 - Article
C2 - 28647468
AN - SCOPUS:85023634547
VL - 25
SP - 1738
EP - 1746
JO - Osteoarthritis and Cartilage
JF - Osteoarthritis and Cartilage
SN - 1063-4584
IS - 10
ER -