Gene Transfer of Dominant-Negative Mutants of Extracellular Signal–Regulated Kinase and c-Jun NH2-Terminal Kinase Prevents Neointimal Formation in Balloon-Injured Rat Artery

Abstract

Abstract-We previously reported that extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK), belonging to mitogen-activated protein kinases, are rapidly activated in balloon-injured artery. Therefore, we examined the role of these kinase activations in neointimal formation by using an in vivo gene transfer technique. We made the dominant-negative mutants of ERK (DN-ERK) and JNK (DN-JNK) to specifically inhibit endogenous ERK and JNK activation, respectively. Before balloon injury, these mutants were transfected into rat carotid artery using the hemagglutinating virus of Japan liposome method. In vivo transfection of DN-ERK and DN-JNK significantly suppressed the activation of ERK and JNK, respectively, after balloon injury, confirming successful expression of the transfected genes. Neointimal formation at 14 and 28 days after injury was prevented by gene transfer of DN-ERK or DN-JNK. Furthermore, bromodeoxyuridine labeling index and total cell-counting analysis at 7 days showed that either DN-ERK or DN-JNK remarkably suppressed smooth muscle cell (SMC) proliferation in both the intima and the media after injury. Gene transfer of wild-type ERK (W-ERK) or JNK (W-JNK) significantly enhanced neointimal hyperplasia at 14 days after injury. Furthermore, DN-ERK and DN-JNK significantly suppressed serum-induced SMC proliferation in vitro. We obtained the first evidence that in vivo gene transfer of DN-ERK or DN-JNK prevented neointimal formation in balloon-injured artery by inhibiting SMC proliferation. Thus, ERK and JNK activation triggers SMC proliferation, leading to neointimal formation. These kinases may be the new therapeutic targets for prevention of vascular diseases.

Role of Pim-1 in Smooth Muscle Cell Proliferation

“…Several signal transduction pathways including c-Jun N-terminal kinase, I B kinase, and p38 mitogen-activated protein kinase are known to be activated by oxidative stress in several cell types. Among the various kinases, inactivation of the c-Jun N-terminal kinase pathway has clearly been shown to suppress VSMC proliferation in a balloon injury model (29), and, thus, we assume that activation of the c-Jun N-terminal kinase pathway at least in part explains the oxidative stress-mediated induction of Pim-1.…”

ERK1-Based Pathway as a New Selective Mechanism To Modulate CCR5 with Natural Antibodies

“…To this end, we transiently nucleofected R5-SupT1-L23 cells with the dominant negative (dn) ERK1 mutant (dnERK1), which was mutated in lysine 72, threonine 202, and tyrosine 204 and was unable to translocate to the nucleus (35,36). At 24 h post nucleofection, the cells were incubated with sera (either CCR5 Ab pos or CCR5 Ab neg) for 150 min and analyzed by Western blot.…”

Borrelia burgdorferi-Induced Expression of Matrix Metalloproteinases from Human Chondrocytes Requires Mitogen-Activated Protein Kinase and Janus Kinase/Signal Transducer and Activator of Transcription Signaling Pathways

“…To confirm the role of p38 MAPK, ERK1/2 and JNK on MMP-1 and MMP-3 induction by B. burgdorferi, we examined expression of MMP-1 and MMP-3 in the presence of specific inhibitors for each pathway. Concentrations of inhibitors were selected based on prior studies of these inhibitors with chondrocytes (9,15,16,21,25,28,29,31,33,34). Cells were in- (Fig.…”