Role of tumor necrosis factor-alpha, interleukin-8, and dexamethasone in the focal adhesion kinase expression by human nucleus pulposus cells.
METHODS
Human nucleus pulposus cells from intervertebral disc specimens were cultured to study the effects of tumor necrosis factor (TNF)-alpha and interleukin (IL)-8 on the focal adhesion kinase (FAK) expression by these cells. The effect of co-stimulation with dexamethasone on the FAK expression by nucleus pulposus cells was also studied.


OBJECTIVE
To evaluate the possible role of activated FAK expressed by the human nucleus pulposus cells and its correlation with inflammatory cytokines (TNF-alpha, IL-8) and dexamethasone.


BACKGROUND
There have been no reported studies showing the correlation between the activated FAK expression by human nucleus pulposus cells with inflammatory cytokines and dexamethasone.


METHODS
The FAK expression in cultured human nucleus pulposus cells was studied, and Western blot and immunofluorescence analysis were performed to assess its relation to TNF-alpha, IL-8, and dexamethasone.


RESULTS
Treatments of TNF-alpha and IL-8 up-regulated the activated FAK expression. Dexamethasone attenuated the cytokine-induced FAK expression. The effects of inflammatory cytokines on the FAK expression were found to be concentration dependent, with greater correlation shown by IL-8 than TNF-alpha.


CONCLUSIONS
TNF-alpha and IL-8 stimulation up-regulated the FAK expression of human nucleus pulposus cells, and the coadministration of dexamethasone attenuated it.
Jee
Bo Keun
BK
Neuroscience Genome Research Center, The Catholic University of Korea, Seoul, Korea.
Surendran
Sibin
S
Park
Koung Min
KM
Lee
Woon Kyu
WK
Han
Chang Whan
CW
Kim
Young Yul
YY
Patinharayil
Gopinathan
G
Kim
Young Hoon
YH
Lee
Kweon Haeng
KH
D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology*; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000096:biosynthesis* / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D016209:Interleukin-8 / Q000494:pharmacology / Q000502:physiology*; D007403:Intervertebral Disc / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology / Q000502:physiology*
D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha; D003907:Dexamethasone; D051416:Focal Adhesion Protein-Tyrosine Kinases