Role of p38 MAP kinase in diperoxovanadate-induced phospholipase D activation in endothelial cells

Abstract

We previously demonstrated that diperoxovanadate (DPV), a synthetic peroxovanadium compound and cell-permeable oxidant that acts as a protein tyrosine phosphatase inhibitor and insulinomimetic, increased phospholipase D (PLD) activation in endothelial cells (ECs). In this report, the regulation of DPV-induced PLD activation by mitogen-activated protein kinases (MAPKs) was investigated. DPV activated extracellular signal-regulated kinase, c-Jun NH2-terminal kinase (JNK), and p38 MAPK in a dose- and time-dependent fashion. Treatment of ECs with p38 MAPK inhibitors SB-203580 and SB-202190 or transient transfection with a p38 dominant negative mutant mitigated the PLD activation by DPV but not by phorbol ester. SB-202190 blocked DPV-mediated p38 MAPK activity as determined by activated transcription factor-2 phosphorylation. Immunoprecipitation of PLD from EC lysates with PLD1 and PLD2 antibodies revealed both PLD isoforms associated with p38 MAPK. Similarly, PLD1 and PLD2 were detected in p38 immunoprecipitates from control and DPV-challenged ECs. Binding assays demonstrated interaction of glutathione S-transferase-p38 fusion protein with PLD1 and PLD2. Both PLD1 and PLD2 were phosphorylated by p38 MAPK in vitro, and DPV increased phosphorylation of PLD1 and PLD2 in vivo. However, phosphorylation of PLD by p38 failed to affect PLD activity in vitro. These results provide evidence for p38 MAPK-mediated regulation of PLD in ECs.

Phospholipase D Activation by Sphingosine 1-Phosphate Regulates Interleukin-8 Secretion in Human Bronchial Epithelial Cells

“…In endothelial cells, S1P is capable of activating p38 mitogenactivated protein kinase (MAPK) (19), and p38 MAPK regulates PLD (69). Furthermore, we have shown in Beas-2B cells that S1P-induced p38 MAPK phosphorylation is 1-butanolinsensitive, whereas ERK1/2 phosphorylation is attenuated with 1-butanol.…”

“…Furthermore, we have shown in Beas-2B cells that S1P-induced p38 MAPK phosphorylation is 1-butanolinsensitive, whereas ERK1/2 phosphorylation is attenuated with 1-butanol. 2 These two MAPKs, particularly p38, have been shown to be involved in NFB activation (69) and IL-8 synthesis (49,52,70). It stands to reason that parallel and concomitant signaling events occur when S1P binds to its receptor(s).…”

Angiotensin II-Induced Akt Activation through the Epidermal Growth Factor Receptor in Vascular Smooth Muscle Cells Is Mediated by Phospholipid Metabolites Derived by Activation of Phospholipase D

“…Moreover, the cPLA 2 -specific inhibitor pyrrolidin-1 also decreased the phosphorylation of p38 MAPK. PLD activation by norepinephrine in VSMC is partially inhibited by either a MEK1 inhibitor (PD98059) (Muthalif et al, 2000;Parmentier et al, 2001b) or a p38 MAP kinase inhibitor (SB203580) (Min do et al, 2002), although SB203580 did not inhibit PLD activity in endothelial cells (Natarajan et al, 2001). However, Ang II-stimulated PLD activity has been reported to be independent of extracellular signal-regulated kinase 1/2 MAPK in VSMC derived from hypertensive rats (Wilkie et al, 1996).…”

Role of Mitogen-activated Protein Kinases in 4-Hydroxy-2-nonenal-induced Actin Remodeling and Barrier Function in Endothelial Cells

“…Although the current study has not characterized any of the Michael adducts formed in lung microvascular ECs, it has been demonstrated that HNE-protein adduct accumulation reflects cellular toxicity compromising tissue survival during heart ischemia, ischemia/reperfusion injury, or pulmonary diseases (18, 19, 38 -40). Exogenously added or endogenously generated in cells, 4-HNE modulates protein function; examples include Na-K-ATPase (57), glucose transporter (58), MAPKs (7)(8)(9)(10)(11)24), phospholipases (1,4,5,59,60), protein kinase C (6), IK␤ kinase (61), and gene expression of ␥-glutamylcysteine synthetase (62). Thus, 4-HNE generated during lipid peroxidation can serve as an extracellular and intracellular signaling molecule altering cellular responses to stress and toxicity.…”