c-Src-dependent MAPKs/AP-1 activation is involved in TNF-α-induced matrix metalloproteinase-9 expression in rat heart-derived H9c2 cells.
TNF-α plays a critical mediator in the pathogenesis of chronic heart failure contributing to cardiac remodeling and peripheral vascular disturbances. The implication of TNF-α in inflammatory responses has been shown to be mediated through up-regulation of inflammatory genes, including matrix metalloproteinase-9 (MMP-9). However, the detailed mechanisms of TNF-α-induced MMP-9 expression are largely unclear in the heart cells. Here, we demonstrated that in rat embryonic-heart derived H9c2 cells, TNF-α could induce MMP-9 mRNA expression associated with an increase in the secretion of MMP-9, determined by real-time PCR, zymography, and promoter activity assays. TNF-α-mediated responses were attenuated by pretreatment with the inhibitor of c-Src (PP1), EGFR (AG1478), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), MEK1/2 (U0126), p38 MAPK (SB202190), JNK1/2 (SP600125), or AP-1 (Tanshinone IIA) and transfection with siRNA of c-Src, EGFR, PDGFR, p110, Akt, or c-Jun. TNF-α stimulated c-Src, PDGFR, and EGFR phosphorylation, which were reduced by PP1. In addition, TNF-α-stimulated Akt phosphorylation was inhibited by PP1, AG1478, AG1296, or LY294002. We further demonstrated that TNF-α markedly stimulated p38 MAPK, p42/p44 MAPK, and JNK1/2 phosphorylation via a c-Src/EGFR, PDGFR/PI3K/Akt pathway. Finally, we showed that, in H9c2 cells, TNF-α-stimulated AP-1 promoter activity, c-Jun mRNA expression, and c-Jun phosphorylation were attenuated by PP1, AG1478, AG1296, LY294002, SB202190, SP600125, or U0126. These results suggested that TNF-α-induced MMP-9 expression is mediated through a c-Src/EGFR, PDGFR/PI3K/Akt/MAPKs/AP-1 cascade in H9c2 cells. Consequently, MMP-9 induction may contribute to cell migration and cardiovascular inflammation.
Department of Physiology and Pharmacology and Health Aging Research Center, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan. chuenmao@mail.cgu.edu.tw
Chuen-Mao
CM
Yang
I-Ta
IT
Lee
Chih-Chung
CC
Lin
Chao-Hung
CH
Wang
Wen-Jin
WJ
Cherng
Li-Der
LD
Hsiao
D000818:Animals; D000081247:CSK Tyrosine-Protein Kinase; D002478:Cells, Cultured; D066246:ErbB Receptors / Q000502:physiology; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000502:physiology*; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D051057:Proto-Oncogene Proteins c-akt / Q000502:physiology; D051381:Rats; D017479:Receptors, Platelet-Derived Growth Factor / Q000502:physiology; D018808:Transcription Factor AP-1 / Q000502:physiology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D019061:src-Family Kinases / Q000502:physiology*
D000081247:CSK Tyrosine-Protein Kinase; D066246:ErbB Receptors; D020780:Matrix Metalloproteinase 9; D020928:Mitogen-Activated Protein Kinases; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D017479:Receptors, Platelet-Derived Growth Factor; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; D019061:src-Family Kinases