Integrated pharmacological preconditioning and memory of cardioprotection: role of protein kinase C and phosphatidylinositol 3-kinase

2005 ◽  
Vol 289 (2) ◽  
pp. H761-H767 ◽  
Author(s):  
Takayuki Okada ◽  
Hajime Otani ◽  
Yue Wu ◽  
Takamichi Uchiyama ◽  
Shiori Kyoi ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Kinase Inhibitor ◽  
Pi3 Kinase ◽  
Neonatal Rat ◽  
Rat Cardiomyocytes ◽  
Simulated Ischemia ◽  
Kinase C ◽  
Pharmacological Preconditioning ◽  
Phosphatidylinositol 3

Although protein kinase C (PKC) and phosphatidylinositol 3 (PI3)-kinase are implicated in cardioprotective signal transduction mediated by ischemic preconditioning, their role in pharmacological preconditioning (PPC) has not been determined. Cultured neonatal rat cardiomyocytes (CMCs) were subjected to simulated ischemia for 2 h followed by 15 min of reoxygenation. PPC of CMCs consisted of administration of 50 μM adenosine, 50 μM diazoxide, and 50 μM S-nitroso- N-acetylpenicillamine (SNAP), each alone or in combination, for 15 min followed by 30 min of washout before simulated ischemia. Although PKC-ε and PI3-kinase were significantly activated during treatment with adenosine, activation of these kinases dissipated after washout. In contrast, PPC combined with adenosine, diazoxide, and SNAP elicited sustained activation of PKC-ε and PI-3 kinase after washout. The combined-PPC, but not the single-PPC, protocol conferred antiapoptotic and antinecrotic effects after reoxygenation. The PKC inhibitor chelerythrine (5 μM) or the PI3-kinase inhibitor LY-294002 (10 μM) given during the washout period partially blocked the activation of PKC-ε and PI3-kinase mediated by the combined-PPC protocol, whereas combined addition of chelerythrine and LY-294002 completely inhibited activation of PKC-ε and PI3-kinase. Chelerythrine or LY-294002 partially blocked antiapoptotic and antinecrotic effects mediated by the combined-PPC protocol, whereas combined addition of chelerythrine and LY-294002 completely abrogated antiapoptotic and antinecrotic effects. These results suggest that the combined-PPC protocol confers cardioprotective memory through sustained and interdependent activation of PKC and PI3-kinase.

scholarly journals Insulin-Induced GLUT4 Translocation Involves Protein Kinase C-λ-Mediated Functional Coupling between Rab4 and the Motor Protein Kinesin

2003 ◽  
Vol 23 (14) ◽  
pp. 4892-4900 ◽  
Author(s):  
Takeshi Imamura ◽  
Jie Huang ◽  
Isao Usui ◽  
Hiroaki Satoh ◽  
Jennie Bever ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Cell Surface ◽  
Kinase Inhibitor ◽  
Motor Protein ◽  
Pi3 Kinase ◽  
Dominant Negative ◽  
Functional Coupling ◽  
Glut4 Translocation ◽  
Kinase C

ABSTRACT Insulin stimulates glucose transport by promoting translocation of GLUT4 proteins from the perinuclear compartment to the cell surface. It has been previously suggested that the microtubule-associated motor protein kinesin, which transports cargo toward the plus end of microtubules, plays a role in translocating GLUT4 vesicles to the cell surface. In this study, we investigated the role of Rab4, a small GTPase-binding protein, and the motor protein KIF3 (kinesin II in mice) in insulin-induced GLUT4 exocytosis in 3T3-L1 adipocytes. Photoaffinity labeling of Rab4 with [γ-32P]GTP-azidoanilide showed that insulin stimulated Rab4 GTP loading and that this insulin effect was inhibited by pretreatment with the phosphatidylinositol 3-kinase (PI3-kinase) inhibitor LY294002 or expression of dominant-negative protein kinase C-λ (PKC-λ). Consistent with previous reports, expression of dominant-negative Rab4 (N121I) decreased insulin-induced GLUT4 translocation by 45%. Microinjection of an anti-KIF3 antibody into 3T3-L1 adipocytes decreased insulin-induced GLUT4 exocytosis by 65% but had no effect on endocytosis. Coimmunoprecipitation experiments showed that Rab4, but not Rab5, physically associated with KIF3, and this was confirmed by showing in vitro association using glutathione S-transferase-Rab4. A microtubule capture assay demonstrated that insulin stimulation increased the activity for the binding of KIF3 to microtubules and that this activation was inhibited by pretreatment with the PI3-kinase inhibitor LY294002 or expression of dominant-negative PKC-λ. Taken together, these data indicate that (i) insulin signaling stimulates Rab4 activity, the association of Rab4 with kinesin, and the interaction of KIF3 with microtubules and (ii) this process is mediated by insulin-induced PI3-kinase-dependent PKC-λ activation and participates in GLUT4 exocytosis in 3T3-L1 adipocytes.

Cardioprotective action of CRF peptide urocortin against simulated ischemia in adult rat cardiomyocytes

2003 ◽  
Vol 284 (1) ◽  
pp. H330-H336 ◽  
Author(s):  
Jennifer M. Gordon ◽  
Gregory J. Dusting ◽  
Owen L. Woodman ◽  
Rebecca H. Ritchie
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Ischemic Preconditioning ◽  
Glucose Deprivation ◽  
Rat Cardiomyocytes ◽  
Adult Rat ◽  
Simulated Ischemia ◽  
Corticotrophin Releasing Factor ◽  
Kinase C ◽  
Protein Kinase C Inhibitor

The major objective of this study was to determine whether urocortin, a member of the corticotrophin-releasing factor (CRF) family, protects adult rat cardiomyocytes from ischemia that has been simulated by glucose deprivation and acidosis. When it was present during simulated ischemia, urocortin (0.1 μM) markedly attenuated the cellular injury, which was assessed by increases in creatine kinase and lactate dehydrogenase levels. This effect was comparable with that observed with adenosine (10 μM). The cardioprotective effect of urocortin was markedly attenuated by the protein kinase C inhibitor chelerythrine and by 5-hydroxydecanoate, an inhibitor of ATP-sensitive K+channels. Cardiomyocytes were also protected from injury by pretreatment with urocortin, either by incubation for 5 min with a subsequent 10-min recovery or incubation for 20 min with a 20-h recovery before simulated ischemia. Similar cardioprotective effects were observed with ischemic preconditioning protocols during both immediate and delayed phases. In conclusion, in adult cardiomyocytes, urocortin has immediate and delayed cardioprotective actions that mimic ischemic preconditioning. These actions are mediated via protein kinase C and ATP-sensitive K+channels.

Role of protein kinase C in T-cell antigen receptor regulation of p21ras: evidence that two p21ras regulatory pathways coexist in T cells

1992 ◽  
Vol 12 (7) ◽  
pp. 3305-3312
Author(s):  
M Izquierdo ◽  
J Downward ◽  
J D Graves ◽  
D A Cantrell
Keyword(s):  
T Cells ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Kinase Inhibitor ◽  
Antigen Receptor ◽  
Permeabilized Cell ◽  
Regulatory Pathways ◽  
Kinase C ◽  
Stimulation Of

T-lymphocyte activation via the antigen receptor complex (TCR) results in accumulation of p21ras in the active GTP-bound state. Stimulation of protein kinase C (PKC) can also activate p21ras, and it has been proposed that the TCR effect on p21ras occurs as a consequence of TCR regulation of PKC. To test the role of PKC in TCR regulation of p21ras, a permeabilized cell system was used to examine TCR regulation of p21ras under conditions in which TCR activation of PKC was blocked, first by using a PKC pseudosubstrate peptide inhibitor and second by using ionic conditions that prevent phosphatidyl inositol hydrolysis and hence diacylglycerol production and PKC stimulation. The data show that TCR-induced p21ras activation is not mediated exclusively by PKC. Thus, in the absence of PKC stimulation, the TCR was still able to induce accumulation of p21ras-GTP complexes, and this stimulation correlated with an inactivation of p21ras GTPase-activating proteins. The protein tyrosine kinase inhibitor herbimycin could prevent the non-PKC-mediated, TCR-induced stimulation of p21ras. These data indicate that two mechanisms for p21ras regulation coexist in T cells: one PKC mediated and one not. The TCR can apparently couple to p21ras via a non-PKC-controlled route that may involve tyrosine kinases.

The protein kinase C inhibitor H-7 activates human neutrophils: effect on shape, actin polymerization, fluid pinocytosis and locomotion

1990 ◽  
Vol 96 (1) ◽  
pp. 99-106
Author(s):  
H.U. Keller ◽  
V. Niggli ◽  
A. Zimmermann ◽  
R. Portmann
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Actin Polymerization ◽  
Kinase Inhibitor ◽  
Human Neutrophils ◽  
Kinase C ◽  
Chemotactic Peptides ◽  
Protein Kinase C Inhibitor ◽  
Shape Changes ◽  
Stimulation Of

The present study demonstrates new properties of H-7. The protein kinase inhibitor H-7 is a potent activator of several neutrophil functions. Stimulation of initially spherical nonmotile neutrophils elicits vigorous shape changes within a few seconds, increases in cytoskeletal actin, altered F-actin distribution, increased adhesiveness and a relatively small increase in pinocytic activity. H-7 has also chemokinetic activities. Depending on the experimental condition, H-7 may elicit or inhibit neutrophil locomotion. It failed to induce chemotaxis. Thus, the response pattern elicited by H-7 is different from that of other leukocyte activators such as chemotactic peptides, PMA or diacylglycerols. The finding that H-7 can elicit shape changes, actin polymerization and pinocytosis suggests that these events can occur without activation of protein kinase C (PKC). PMA-induced shape changes and stimulation of pinocytosis were not inhibited by H-7.

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