Involvement of p42/p44 MAPK, p38 MAPK, JNK and nuclear factor-kappa B in interleukin-1beta-induced matrix metalloproteinase-9 expression in rat brain astrocytes.
Matrix metalloproteinase (MMP)-9 expression induced by interleukin-1beta (IL-1beta) was investigated in rat brain astrocyte-1 (RBA-1). Here we report that the mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-kappaB) pathways participate in the induction of MMP-9 expression by IL-1beta. Zymographic, western blotting, and RT-PCR analyses showed that IL-1beta increased expression of MMP-9 mRNA and protein, which were inhibited by inhibitors of MEK1/2 (U0126), p38 (SB202190), and JNK (SP600125). In accordance with these findings, IL-1beta stimulated phosphorylation of p42/p44 MAPK, p38, and c-Jun N-terminal kinase (JNK), which was attenuated by U0126, SB202190, or SP600125, respectively. Furthermore, this up-regulation of MMP-9 mRNA and protein was blocked by a specific NF-kappaB inhibitor helenalin. Consistently, IL-1beta-stimulated translocation of NF-kappaB into the nucleus and degradation of inhibitory kappa B-alpha (IkappaB-alpha) was revealed by western blotting and immunofluorescence staining, which was blocked by helenalin, but not by U0126, SB202190, or SP600125. Taken together, these results suggest that in RBA-1 cells, activation of p42/p44 MAPK, p38, JNK and NF-kappaB pathways is essential for IL-1beta-induced MMP-9 gene expression via transcription and translation processes. An increased understanding of the signal transduction pathways involved in IL-1beta-induced MMP-9 expression on RBA-1 may be of potential therapeutic value in the treatment of inflammatory disease.
Wu
Cheng-Ying
CY
Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan.
Hsieh
Hsi-Lung
HL
Jou
Mei-Jie
MJ
Yang
Chuen-Mao
CM
D000818:Animals; D001253:Astrocytes / Q000187:drug effects* / Q000378:metabolism; D015153:Blotting, Western / Q000379:methods; D001921:Brain / Q000166:cytology*; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005455:Fluorescent Antibody Technique / Q000379:methods; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000502:physiology*; D007375:Interleukin-1 / Q000494:pharmacology*; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000145:classification / Q000502:physiology*; D016328:NF-kappa B / Q000502:physiology*; D051381:Rats; D013997:Time Factors; D014178:Translocation, Genetic / Q000502:physiology
D004791:Enzyme Inhibitors; D007375:Interleukin-1; D016328:NF-kappa B; D020928:Mitogen-Activated Protein Kinases; D020780:Matrix Metalloproteinase 9