Wogonin is a flavonoid isolated from Scutellaria baicalensis Georgi, a traditional Chinese medicine, and it possesses antioxidant and anti-inflammatory effects. The aim of this study is to investigate the in vivo effect of wogonin on myocardial ischemia/reperfusion injury in an open-chest anesthetized rat model, which was induced by 45-minute left coronary artery occlusion and 2-hour reperfusion. Rats were treated with wogonin (5, 10, and 20 mg/kg, intraperitoneal) 40 minutes before ischemia or treatment with 10 mg/kg of wogonin 15 minutes after occlusion. Pretreatment with 10 mg/kg of wogonin significantly delayed the occurrence of ventricular premature contractions and tachycardia, and it suppressed the incidence of ventricular tachycardia and ventricular fibrillation, and mortality elicited by ischemia when compared with that in the control group, accompanied by reducing the arrhythmia scores. After 2-hour reperfusion, pretreatment and posttreatment with wogonin significantly reduced the infarct size and plasma levels of creatine kinase muscle-brain fraction and lactate dehydrogenase. Wogonin also significantly reduced the elevation of plasma tissue necrosis factor-α and superoxide anion production in the myocardium with ischemia/reperfusion. The expression of monocyte chemoattractant protein-1, phosphorylated p38 mitogen-activated protein kinase, p65 and IκBα, and active caspase-3 in ischemic myocardium pronouncedly increased in the control group; these were significantly attenuated by treatment with wogonin. In conclusion, wogonin demonstrated in vivo cardioprotective effects by the attenuation of the severity of ischemia-induced arrhythmias and irreversible ischemia/reperfusion injury, which is associated with its antioxidant capacity and anti-inflammatory effects. The suppression of nuclear factor-κB and p38 mitogen-activated protein kinase activation and the inhibition of monocyte chemoattractant protein-1 expression contribute to the beneficial effects of wogonin.
From the *Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan; †Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan; ‡Graduate Institute of Chinese Pharmaceutical Sciences, China Medical University, Taichung, Taiwan; §Department of Nursing, HungKuang University, Taichung, Taiwan; ¶Department of Obstetrics and Gynecology, Army Forces Tao-Yuan General Hospital, Tao-Yuan, Taiwan; and ‖Department of Pharmacology, Taipei Medical University, Taipei, Taiwan.
Received for publication Augst 21, 2010; accepted March 14, 2011.
Supported by research grants from the National Science Council (NSC 93-2320-B-016-039 and 97-2320-B-016-004), Taipei, Taiwan.
The authors declare no conflicts of interest.
Reprints: Joen-Rong Sheu, PhD, Department of Pharmacology, Taipei Medical University, 250 Wu-Hsing St, Taipei 110, Taiwan (e-mail: email@example.com).