TY - JOUR
T1 - Transforming growth factor β1 rescues serum deprivation-induced apoptosis via the mitogen-activated protein kinase (MAPK) pathway in macrophages
AU - Chin, Beek Yoke
AU - Petrache, Irina
AU - Choi, Augustine M.K.
AU - Choi, Mary E.
PY - 1999/4/16
Y1 - 1999/4/16
N2 - Cell death and cell survival are central components of normal development and pathologic states. Transforming growth factor β1 (TGF- β1) is a pleiotropic cytokine that regulates both cell growth and cell death. To better understand the molecular mechanisms that control cell death or survival, we investigated the role of TGF-β1 in the apoptotic process by dominant-negative inhibition of both TGF-β1 and mitogen-activated protein kinase (MAPK) signaling pathways. Murine macrophages (RAW 264.7) undergo apoptosis following serum deprivation, as determined by DNA laddering assay. However, apoptosis is prevented in serum-deprived macrophages by the presence of exogenous TGF-β1. Using stably transfected RAW 264.7 cells with the kinase-deleted dominant-negative mutant of TβR-II (TβR-II(M)) cDNA, we demonstrate that this protective effect by TGF-β1 is completely abrogated. To determine the downstream signaling pathways, we examined TGF-β1 effects on the MAPK pathway. We show that TGF-β1 induces the extracellular signal- regulated kinase (ERK) activity in a time-dependent manner up to 4 h after stimulation. Furthermore, TGF-β1 does not rescue serum deprivation-induced apoptosis in RAW 264.7 cells transfected with a dominant-negative mutant MAPK (ERK2) cDNA or in wild type RAW 264.7 cells in the presence of the MAPK kinase (MEK1) inhibitor. Taken together, our data demonstrate for the first time that TGF-β1 is an inhibitor of apoptosis in cultured macrophages and may serve as a cell survival factor via TβR-II-mediated signaling and downstream intracellular MAPK signaling pathway.
AB - Cell death and cell survival are central components of normal development and pathologic states. Transforming growth factor β1 (TGF- β1) is a pleiotropic cytokine that regulates both cell growth and cell death. To better understand the molecular mechanisms that control cell death or survival, we investigated the role of TGF-β1 in the apoptotic process by dominant-negative inhibition of both TGF-β1 and mitogen-activated protein kinase (MAPK) signaling pathways. Murine macrophages (RAW 264.7) undergo apoptosis following serum deprivation, as determined by DNA laddering assay. However, apoptosis is prevented in serum-deprived macrophages by the presence of exogenous TGF-β1. Using stably transfected RAW 264.7 cells with the kinase-deleted dominant-negative mutant of TβR-II (TβR-II(M)) cDNA, we demonstrate that this protective effect by TGF-β1 is completely abrogated. To determine the downstream signaling pathways, we examined TGF-β1 effects on the MAPK pathway. We show that TGF-β1 induces the extracellular signal- regulated kinase (ERK) activity in a time-dependent manner up to 4 h after stimulation. Furthermore, TGF-β1 does not rescue serum deprivation-induced apoptosis in RAW 264.7 cells transfected with a dominant-negative mutant MAPK (ERK2) cDNA or in wild type RAW 264.7 cells in the presence of the MAPK kinase (MEK1) inhibitor. Taken together, our data demonstrate for the first time that TGF-β1 is an inhibitor of apoptosis in cultured macrophages and may serve as a cell survival factor via TβR-II-mediated signaling and downstream intracellular MAPK signaling pathway.
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U2 - 10.1074/jbc.274.16.11362
DO - 10.1074/jbc.274.16.11362
M3 - Article
C2 - 10196228
AN - SCOPUS:0000432767
VL - 274
SP - 11362
EP - 11368
JO - The Journal of biological chemistry
JF - The Journal of biological chemistry
SN - 0021-9258
IS - 16
ER -