Treatment with Sheng-Mai-San Reduces Myocardial Infarct Size Through Activation of Protein Kinase C and Opening of Mitochondrial KATP Channel

2001 ◽  
Vol 29 (02) ◽  
pp. 367-375 ◽  
Author(s):  
Ningyuan Wang ◽  
Shinya Minatoguchi ◽  
Yoshihiro Uno ◽  
Masazumi Arai ◽  
Kazuaki Hashimoto ◽  
...  

Sheng-Mei-San (SMS), a traditional Chinese formulation comprising Radix Ginseng, Radix Ophiopogonis and Fructus Schisandrae, has long been used for more than 700 years for patients with coronary heart disease. We attempted to clarify 1) whether SMS reduces myocardial infarct size, and 2) whether the infarct size-reducing effect of SMS is related to activation of protein kinase C and the opening of the mitochondrial KATP channels in Japanese white rabbits without collateral circulation. The results indicate that three days treatment but not acute treatment with SMS reduces myocardial infarct size through activation of protein kinase C and opening of the mitochondrial KATP channels.

2015 ◽  
Vol 78 (9) ◽  
pp. 506-512
Author(s):  
Chia-Yu Tang ◽  
Chang-Chi Lai ◽  
Shu-Chiung Chiang ◽  
Kuo-Wei Tseng ◽  
Cheng-Hsiung Huang

1995 ◽  
Vol 268 (1) ◽  
pp. H426-H431 ◽  
Author(s):  
Y. Li ◽  
R. A. Kloner

Protein kinase C (PKC) has been implicated in the cardioprotective effects of ischemic preconditioning in rabbits, but whether it plays a role in rats is unknown. We tested this preconditioning PKC theory by assessing whether the inhibition of PKC with calphostin C, a potent and specific inhibitor of PKC, can block the preconditioning effects in this model. Four groups of rats were studied: 1) control + vehicle, 2) control + calphostin C, 3) preconditioning + vehicle, and 4) preconditioning + calphostin C. All rats underwent 90 min of coronary occlusion followed by 4 h of reperfusion; in addition, preconditioned rats underwent three 3-min episodes of ischemia and 5 min of reperfusion before the 90 min of ischemia. Two injections of vehicle or calphostin C (0.1 mg/kg) were administered in intravenous boluses 29 min and 3 min before the 90-min coronary occlusion, i.e., one dose was given 5 min before preconditioning, and another dose was given between preconditioning and the sustained 90 min of ischemia in preconditioned rats. After 4 h of reperfusion, the area at risk (AR) was delineated by dye injection and area of necrosis was assessed by triphenyltetrazolium chloride staining. The electrocardiogram was recorded for the incidence of ventricular tachycardia (VT) and ventricular fibrillation. AR was similar in all four groups. In the nonpreconditioned control rats receiving vehicle, myocardial infarct size expressed as a percentage of the AR averaged 45.7 +/- 1.7%. Pretreatment with calphostin C had no effect on infarct size (48.9 +/- 3.4%) in nonpreconditioned control rats.(ABSTRACT TRUNCATED AT 250 WORDS)


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Shohei Sumi ◽  
Masamitsu Iwasa ◽  
Hiroyuki Kobayashi ◽  
Shinji Yasuda ◽  
Takahiko Yamaki ◽  
...  

It has been reported that granulocyte-colony-stimulating factor(G-CSF) improves cardiac function after myocardial infarction (MI). However, its direct effect on the myocardium and its signaling pathway remain unclear. We examined the acute beneficial effect of G-CSF on myocardial infarct size and its precise mechanisms in a rabbit model of myocardial infarction. In 80 Japanese white rabbits, MI was induced by 30 min of ischemia and 48 hours of reperfusion. Rabbits were intravenously injected with 10 μg/kg of G-CSF (G-CSF group, n=10) or saline (control group, n=10) immediately after reperfusion. The G-CSF+5HD group (n=10) was injected with 5-HD(5-hydroxydecanoate, a mitochondrial KATP channel blocker) 5 min before G-CSF injection. The G-CSF +wortmaninn group (n=10) was injected wortmaninn (0.6mg/kg) 5 min before G-CSF injection. G-CSF+L-NAME group (n=10) was injected with L-NAME (10mg/kg) 5 min before G-CSF injection. The 5HD alone (n=10), wortmannin alone (n=10), L-NAME alone (n=10) groups were respectively injected 5HD, wortmannin and L-NAME immediately after reperfusion. Myocardial infarct size was calculated as a percentage of the risk area of the left ventricle. Western blot analysis was performed to examine the Akt and phospho-Akt and phospho-eNOS in the ischemic myocardium at 48 hours of reperfusion. The infarct size was significantly smaller in the G-CSF group (26.7±2.7%) than in the control group (42.3±4.6%). The infarct size-reducing effect of G-CSF was completely blocked by 5-HD (42.5±1.66%), wortmaninn(44.7±4.81) and L-NAME (42.1±4.2%). Wortmannin, L-NAME or 5HD alone did not affect the infarct size. Western blotting showed higher expression of phospho-Akt and phosho-eNOS in the infarct area in the G-CSF group than in the control group. G-CSF administered immediately after reperfusion reduces myocardial infarct size via activation of PI3K, Akt, eNOS and opening the mitochondrial KATP channels.


2005 ◽  
Vol 102 (2) ◽  
pp. 371-378 ◽  
Author(s):  
Ye Zhang ◽  
Michael G. Irwin ◽  
Tak Ming Wong ◽  
Mai Chen ◽  
Chun-Mei Cao

Background Remifentanil preconditioning (RPC) reduces the infarct size in anesthetized rat hearts, and this effect seems to be mediated by all three types of opioid receptors (ORs). Because there is evidence of only kappa- and delta- but not mu-ORs in the rat heart, the authors investigated whether RPC confers cardioprotection via cardiac kappa- and delta-OR as well as via extracardiac mu-OR agonist activity. The authors also investigated the involvement of signaling mechanisms, namely protein kinase C and mitochondrial adenosine triphosphate-sensitive potassium (KATP) channels. Methods The hearts of male Sprague-Dawley rats weighing 190-210 g were removed, mounted on a Langendorff apparatus, and perfused retrogradely at 100 cm H2O with Krebs-Ringer's solution. All hearts were subjected to 30 min of ischemia and 2 h of reperfusion. The study consisted of three series of experiments on the effect of ischemic preconditioning or RPC (10, 50, and 100 ng/ml remifentanil) after blockade of OR subtypes (delta-OR antagonist naltrindol, kappa-OR antagonist nor-binaltorphimine, and mu-OR antagonist CTOP). The involvement of protein kinase C or the KATP channel in the cardioprotection of RPC was also investigated using specific blockers in each group. RPC was produced by three cycles of 5-min perfusion of remifentanil in Krebs-Ringer's solution interspersed with a 5-min reperfusion with Krebs solution only. Infarct size, as a percentage of the area at risk, was determined by 2,3,5-triphenyltetrazolium staining. Results Infarct size as a percentage of the area at risk was significantly reduced after RPC from 51.9 +/- 5.0% (control, n = 8) to 36.2 +/- 10.0% (100 ng/ml RPC, n = 8, P < 0.01). This effect was stopped by pretreatment with naltrindol (52.3 +/- 5.2%) and nor-binaltorphimine (43.5 +/- 6.0%) but not CTOP (37.1 +/- 6.0%). Chelerythrine and GF109203X, both protein kinase C inhibitors, abolished the effects of RPC or ischemic preconditioning on infarct size as a percentage of area at risk. 5-Hydroxydecanoate (a selective mitochondrial KATP channel blocker) also abolished the cardioprotection of RPC and IPC, but HMR-1098 (a selective inhibitor of the sarcolemmal KATP channel) did not. Conclusion Cardiac delta- and kappa- but not mu-ORs mediate the cardioprotection produced by RPC. Both protein kinase C and the mitochondrial KATP channel were involved in this effect.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Shinya Minatoguchi ◽  
Hiroaki Ushikoshi ◽  
Narantuya Bao ◽  
Hiroyuki Kobayashi ◽  
Shinji Yasuda ◽  
...  

Background: Acarbose, an anti-diabetic drug, is an α– glucosidase inhibitor that can inhibit glucose absorption in the intestine. A recent large-scale clinical trial, STOP-NIDDM, showed that acarbose reduces the risk of myocardial infarction. We examined whether acarbose reduces myocardial infarct size and investigated its mechanisms. Methods and Results: Rabbits were fed with one of four diets in this study: normal chow, 30 mg acarbose/100 g chow, 8 g sucrose/100 g chow, or 30 mg acarbose plus 8 g sucrose/100 g chow for 7 days. Rabbits were assigned randomly to one of eight groups: control (n=10), acarbose (n=10), sucrose (n=10), acarbose+sucrose (n=10), acarbose+i.v. 5-hydroxydecanoate (5HD, a mitochondrial KATP channel blocker, 5 mg/kg) (n=10), 5HD (i.v. 5 mg/kg, n=10), acarbose+exendin(9 –39) (n=10, a Glucagon-Like Peptide-1(GLP-1) receptor blocker, 3 nmol/l) (45.4±1.2%) and exendin(9 –39)(n=10). Rabbits then underwent 30 min of coronary occlusion followed by 48 h reperfusion. Postprandial blood glucose levels were highest in the sucrose group and higher in the control groups, but decreased in the acarbose and sucrose+acarbose groups. The infarct size as a percentage of the left ventricular area at risk was reduced significantly in the acarbose (19.4±2.3%) and sucrose+acarbose groups (19.0±5.6%) as compared with the sucrose (47.4±4.2%) and control groups (42.8±5.4%). The infarct size-reducing effect of acarbose was abolished by 5HD (43.4±4.7%) and exendin(9 –39) (45.4±1.2%). The 5HD and exendin(9 –39) by itself did not affect the infarct size. Myocardial interstitial 2,5-DHBA levels, an indicator of hydroxyl radicals, increased during reperfusion after 30 min of ischemia but this increase was inhibited in the acarbose group. Conclusions: Acarbose reduces myocardial infarct size via stimulation of GLP-1 receptors, opening mitochondrial KATP channels, and preventing hydroxyl radical production.


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