Cardioprotection induced by cardiac-specific overexpression of fibroblast growth factor-2 is mediated by the MAPK cascade

2005 ◽  
Vol 289 (5) ◽  
pp. H2167-H2175 ◽  
Author(s):  
Stacey L. House ◽  
Kevin Branch ◽  
Gilbert Newman ◽  
Thomas Doetschman ◽  
Jo El J. Schultz

Our laboratory showed previously that cardiac-specific overexpression of FGF-2 [FGF-2 transgenic (Tg)] results in increased recovery of contractile function and decreased infarct size after ischemia-reperfusion injury. MAPK signaling is downstream of FGF-2 and has been implicated in other models of cardioprotection. Treatment of FGF-2 Tg and wild-type hearts with U-0126, a MEK-ERK pathway inhibitor, significantly reduced recovery of contractile function after global low-flow ischemia-reperfusion injury in FGF-2 Tg (86 ± 2% vehicle vs. 66 ± 4% U-0126; P < 0.05) but not wild-type (61 ± 7% vehicle vs. 67 ± 7% U-0126) hearts. Similarly, MEK-ERK inhibition significantly increased myocardial infarct size in FGF-2 Tg (12 ± 3% vehicle vs. 31 ± 2% U-0126; P < 0.05) but not wild-type (30 ± 4% vehicle vs. 36 ± 7% U-0126) hearts. In contrast, treatment of FGF-2 Tg and wild-type hearts with SB-203580, a p38 inhibitor, did not abrogate FGF-2-induced cardioprotection from postischemic contractile dysfunction. Instead, inhibition of p38 resulted in decreased infarct size in wild-type hearts (30 ± 4% vehicle vs. 11 ± 2% SB-203580; P < 0.05) but did not alter infarct size in FGF-2 Tg hearts (12 ± 3% vehicle vs. 14 ± 1% SB-203580). Western blot analysis of ERK and p38 activation revealed signaling alterations in FGF-2 Tg and wild-type hearts during early ischemia or reperfusion injury. In addition, MEK-independent ERK inhibition by p38 was observed during early ischemic injury. Together these data suggest that activation of ERK and inhibition of p38 by FGF-2 is cardioprotective during ischemia-reperfusion injury.

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Yasuo M Tsutsumi ◽  
Yoshihiro Ishikawa ◽  
David M Roth ◽  
Hemal H Patel

Introduction: Caveolae are small, flask-like invaginations of the plasma membrane. Caveolins are structural proteins found in caveolae that have scaffolding properties to allow organization of signaling. We have recently shown that both caveolin-1 and caveolin-3 knockout (Cav-1 KO and Cav-3 KO, respectively) mice are unable to be protected from myocardial ischemia-reperfusion injury by acute treatment with volatile anesthetics. Therefore, we tested the hypothesis that delayed cardiac protection induced by volatile anesthetics is caveolin-dependent. Methods: Biochemical assays were performed in excised hearts. Electron microscopy was used to assess caveolae formation. An in vivo mouse model of ischemia-reperfusion injury with delayed anesthetic preconditioning (delayed APC) was tested in wild-type (WT), Cav-1 KO, and Cav-3 KO mice. Mice were exposed to 30 min isoflurane or oxygen and allowed to recover for 24 h. After 24 h recovery, mice underwent 30 min left anterior descending coronary artery occlusion, followed by 2 h of reperfusion at which time infarct size was determined. Results: To elucidate a role for caveolins in delayed APC, wild-type mice were exposed to delayed APC and hearts were fractionated on a discontinuous sucrose gradient to isolate buoyant caveolar membranes. Delayed APC increased the amount of Cav-3 protein but not Cav-1 protein in buoyant fractions. Glucose transporter-4 (GLUT-4), known to interact with Cav-3 and affect cardiac protection, was also increased in buoyant fractions after APC. Microscopically distinct caveolae were observed in WT and Cav-1 KO mice but not Cav-3 KO mice. We assessed the impact of caveolae formation in induction of delayed APC. Infarct size as a percent of the area at risk was reduced by isoflurane in WT (24.0 ± 2.5% vs. 45.1 ± 2.9%, p < 0.05) and Cav-1 KO mice (27.2 ± 4.4%). Cav-3 KO mice did not show delayed APC (41.5 ± 2.2%). Conclusions: These results demonstrate that isoflurane-induced delayed preconditioning involves translocation of Cav-3 and GLUT-4 to caveolae and the presence of microscopically distinct caveolae (dependent on Cav-3 expression) are a requisite for induction of delayed protection in the myocardium. This research has received full or partial funding support from the American Heart Association, AHA Western States Affiliate (California, Nevada & Utah).


PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254712
Author(s):  
Shoichiro Nohara ◽  
Mai Yamamoto ◽  
Hideo Yasukawa ◽  
Takanobu Nagata ◽  
Jinya Takahashi ◽  
...  

Ischemic preconditioning (IPC) is the most powerful endogenous cardioprotective form of cellular adaptation. However, the inhibitory or augmenting mechanism underlying cardioprotection via IPC remains largely unknown. Suppressor of cytokine signaling-3 (SOCS3) is a cytokine-inducible potent negative feedback regulator of the signal transducer and activator of transcription-3 (STAT3) signaling pathway. Here, we aimed to determine whether cardiac SOCS3 deficiency and IPC would synergistically reduce infarct size after myocardial ischemia reperfusion injury. We evaluated STAT3 activation and SOCS3 induction after ischemic conditioning (IC) using western blot analysis and real-time PCR, and found that myocardial IC alone transiently activated myocardial STAT3 and correspondingly induced SOCS3 expression in wild-type mice. Compared with wild-type mice, cardiac-specific SOCS3 knockout (SOCS3-CKO) mice showed significantly greater and more sustained IC-induced STAT3 activation. Following ischemia reperfusion, IPC substantially reduced myocardial infarct size and significantly enhanced STAT3 phosphorylation in SOCS3-CKO mice compared to in wild-type mice. Real-time PCR array analysis revealed that SOCS3-CKO mice after IC exhibited significantly increased expressions of several anti-apoptotic genes and SAFE pathway-related genes. Moreover, real-time PCR analysis revealed that myocardial IC alone rapidly induced expression of the STAT3-activating cytokine erythropoietin in the kidney at 1 h post-IC. We also found that the circulating erythropoietin level was promptly increased at 1 h after myocardial IC. Myocardial SOCS3 deficiency and IPC exert synergistic effects in the prevention of myocardial injury after ischemia reperfusion. Our present results suggest that myocardial SOCS3 is a potent inhibitor of IPC-induced cardioprotection, and that myocardial SOCS3 inhibition augment IPC-mediated cardioprotection during ischemia reperfusion injury.


2001 ◽  
Vol 281 (4) ◽  
pp. H1751-H1758 ◽  
Author(s):  
Rachael J. Cerniway ◽  
Zequan Yang ◽  
Marlene A. Jacobson ◽  
Joel Linden ◽  
G. Paul Matherne

A3 adenosine receptors (A3ARs) have been implicated in regulating mast cell function and in cardioprotection during ischemia-reperfusion injury. The physiological role of A3ARs is unclear due to the lack of widely available selective antagonists. Therefore, we examined mice with targeted gene deletion of the A3AR together with pharmacological studies to determine the role of A3ARs in myocardial ischemia-reperfusion injury. We evaluated the functional response to 15-min global ischemia and 30-min reperfusion in isovolumic Langendorff hearts from A3AR−/−and wild-type (A3AR+/+) mice. Loss of contractile function during ischemia was unchanged, but recovery of developed pressure in hearts after reperfusion was improved in A3AR−/− compared with wild-type hearts (80 ± 3 vs. 51 ± 3% at 30 min). Tissue viability assessed by efflux of lactate dehydrogenase was also improved in A3AR−/− hearts (4.5 ± 1 vs. 7.5 ± 1 U/g). The adenosine receptor antagonist BW-A1433 (50 μM) decreased functional recovery following ischemia in A3AR−/− but not in wild-type hearts. We also examined myocardial infarct size using an intact model with 30-min left anterior descending coronary artery occlusion and 24-h reperfusion. Infarct size was reduced by over 60% in A3AR−/− hearts. In summary, targeted deletion of the A3AR improved functional recovery and tissue viability during reperfusion following ischemia. These data suggest that activation of A3ARs contributes to myocardial injury in this setting in the rodent. Since A3ARs are thought to be present on resident mast cells in the rodent myocardium, we speculate that A3ARs may have proinflammatory actions that mediate the deleterious effects of A3AR activation during ischemia-reperfusion injury.


2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Jingrui Chen ◽  
Yuening Liu ◽  
Peng Xia ◽  
Zhaokang Cheng

Background: Reperfusion therapy, an effective treatment for myocardial infarction, triggers ischemia-reperfusion (I/R) injury and eventually may result in heart failure. Retinoblastoma-like 2 (Rbl2), a major retinoblastoma family member expressed in the heart, maintains the postmitotic state of adult cardiac myocytes. However, the role of Rbl2 in myocardial I/R injury remains unclear. We hypothesize that Rbl2 deficiency exacerbates myocardial injury following I/R. Methods and results: Wild type C57BL/6 (8–10-week, male) mice were subjected to 30 min of ischemia followed reperfusion. I/R induced phosphorylation of Rbl2 at Ser952, which has been associated with Rbl2 protein inactivation. To determine the role of Rbl2 in vivo, Rbl2-deficient mice and wild-type littermates were subjected to I/R and infarct size was evaluated by Evans blue/TTC staining. Rbl2 deficiency significantly increased infarct size at 24 h post I/R when compared with wild-type littermate controls. Echocardiography and Masson’s trichrome staining revealed that Rbl2 deficiency exacerbated I/R-induced cardiac dysfunction and fibrosis. Moreover, ablation of Rbl2 exacerbated I/R-induced cardiomyocyte apoptosis, as evidenced by the increased TUNEL positive signal. Consistently, knockdown of Rbl2 augmented H 2 O 2 -induced cleavage of PARP and caspase 3 in neonatal rat cardiomyocytes , suggesting that depletion of Rbl2 exacerbated oxidative stress-induced cardiomyocyte apoptosis. Mechanistically, both I/R and H 2 O 2 induced expression of the pro-apoptotic protein BNIP3, which was augmented by depletion of Rbl2. Since the BNIP3 promoter contains an E2F-binding site, we further examined the levels of the transcriptional activator E2F1 and the transcriptional repressor E2F4. Western blotting revealed that disruption of Rbl2 reduced E2F4 but increased E2F1 levels in mouse heart both at baseline and following I/R. Conclusion: Our findings suggest that Rbl2 deficiency exacerbates cardiomyocyte apoptosis and ischemia-reperfusion injury by augmenting E2F1-mediated BNIP3 expression.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Sverre E. Aune ◽  
Steve T. Yeh ◽  
Periannan Kuppusamy ◽  
M. Lakshmi Kuppusamy ◽  
Mahmood Khan ◽  
...  

The neutrophil elastase inhibitor sivelestat (ONO-5046) possesses unknown mechanisms of cardioprotection when infused following global ischemia, even in the absence of neutrophils. Since myocardial ischemia-reperfusion injury is strongly associated with endothelial dysfunction and reactive oxygen species (ROS) generation during reperfusion, we have tested the hypothesis that infusion of sivelestat during postischemic low flow would preserve endothelial and contractile function and reduce infarct size through an ROS-mediated mechanism. Isolated male rat hearts, subjected to global ischemia of 25 minutes, were reperfused with low flow with or without sivelestat followed by a full flow reperfusion. Hearts treated with sivelestat showed a significant improvement of LV contractile function and a reduction in infarct size. Infusion of L-NAME (nonspecific blocker of endothelial nitric oxide synthase (eNOS)) along with sivelestat during reperfusion reversed the preservation of contractile function and infarct size.In vitroEPR spin trapping experiments showed that sivelestat treatment decreased superoxide adduct formation in bovine aortic endothelial cells (BAECs) subjected to hypoxia-reoxygenation. Similarly, dihydroethidine (DHE) staining showed decreased superoxide production in LV sections from sivelestat-treated hearts. Taken together, these results indicate that sivelestat infusion during postischemic low flow reduces infarct size and preserves vasoreactivity in association with decreased ROS formation and the preservation of nitric oxide.


2000 ◽  
Vol 278 (3) ◽  
pp. H755-H761 ◽  
Author(s):  
Silvia Bertuglia ◽  
Antonio Colantuoni

Ischemia shifts the anticoaugulant/procoagulant balance of the endothelium in favor of activation of coagulation. We studied whether cheek pouch microcirculation of leukopenic hamsters was protected by tissue plasminogen activator (tPA) (50 μg/100 g body wt) against ischemia-reperfusion injury. Adherent leukocytes, total perfused capillary length (PCL), permeability increase, and arteriolar and venular red blood cell (RBC) velocity were investigated by fluorescence microscopy. Measurements were made at control, 30 or 60 min of ischemia, and at 30 or 60 min of reperfusion. Hamsters were made leukopenic by treatment with cyclophosphamide (20 mg/100 g body wt ip, 4 days before the experiment), which decreased circulating leukocyte count by 85–90%. Leukopenic hamsters undergoing 30 min of ischemia followed by 30 min of reperfusion showed no significant decrease in PCL or increased permeability. Leukopenic hamsters undergoing 60 min of ischemia followed by 60 min of reperfusion presented a significant decrease in microvascular perfusion where PCL was 28 ± 7% of baseline, low-flow conditions, and increased permeability. In leukopenic hamsters treated with tPA there was complete protection of capillary perfusion with no significant changes in permeability or arteriolar and venular RBC velocity. In conclusion, thrombus formation may be an additional and independent factor that with leukocyte-mediated mechanisms determines ischemia-reperfusion injury.


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