Possible mechanism of betel-quid-extract-induced expression of matrix metalloproteinase-2.
OBJECTIVE
Betel quid extract (BQE) has been demonstrated to induce matrix metalloproteinase (MMP)-2 expression. This study aimed to establish the possible mechanism involved in this event.


METHODS
Western blotting, reverse-transcription polymerase chain reaction, and gelatin zymography were used to study the expression level of MMP-2. LY294002, PD98059, U0126, N-acetyl-L-cysteine, SB203580, SP600125, and Bay 11-7082 were used to pretreat OECM-1 cells before BQE treatment and MMP-2 detection.


RESULTS
OECM-1 cells were subjected to short-term (10 minutes) or long-term (24 hours) BQE treatment (designated as SBT and LBT, respectively), and we found that both treatments increased MMP-2 protein and extracellular signal-regulated kinase (ERK) phosphorylation levels in a concentration- and time-dependent manner. LBT also increased MMP-2 mRNA level. LBT-induced MMP-2 secretion was not inhibited by PD98059 (up to 50 μM) when ERK was effectively blocked, but was attenuated by LY294002 (0-10 μM) in a concentration-dependent manner. This LBT effect was inhibited strongly by SB203580 (10 μM), SP600125 (10 μM), and Bay 11-7082 (10 μM) and mildly by N-acetyl-L-cysteine (5 mM), but not by U0126 (10 μM).


CONCLUSIONS
Both SBT and LBT upregulate MMP-2 expression, and LBT-induced MMP-2 expression might be mediated by phosphoinositide 3-kinase, p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, and nuclear factor-κB, and to a lesser extent, by reactive oxygen species, rather than by ERK.
Department of Ophthalmology, Taipei Veterans General Hospital, Taipei Medical University, Taipei, Taiwan.
Yu-Chi
YC
Liu
Mei-Huei
MH
Lin
Shyun-Yeu
SY
Liu
Wei-Fan
WF
Chiang
Li-Lin
LL
Chen
Tai-Chi
TC
Chen
Yon-Chi
YC
Cheng
Kai-Chen
KC
Hsu
Pse-Chou
PC
Cheng
Chin-Hai
CH
Lee
Young-Chau
YC
Liu
D000818:Animals; D001114:Areca / Q000009:adverse effects*; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D008409:Mastication; D020778:Matrix Metalloproteinase 2 / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D009062:Mouth Neoplasms / Q000201:enzymology; D018514:Plant Structures / Q000009:adverse effects*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D015854:Up-Regulation / Q000187:drug effects*
D012333:RNA, Messenger; D020778:Matrix Metalloproteinase 2