| Coronary artery disease (CAD) is one of the most dangerous diseases threatening human’s health due to its high morbidity and mortality, which has attracted the attention of medical workers around the world. The serious complication, like ischemia/reperfusion (I/R) injury, has become the biggest obstacle in the clinical treatment of myocardial ischemia. Myocardial ischemia causes I/R injury, both of them have close relationship and mutual influence. Therefore, the treatment of CAD should take into account I/R injury. Finding effective drugs to treat CAD and prevent its prognosis have crucial clinical values.The plant Gentianella acuta belongs to Gentianella genus of Gentianaceae family. It has the effects of clearing heat, cholagogue and eliminating jaundice. In folk, this plant is used to treat arrhythmia and coronary artery disease. However, the studies on chemistry and pharmacology of this plant are seldom reported. For the purpose of making full use of this medicinal plant, this paper focuses on the constituents and pharmacological activity of ameliorating ischemia myocardial of G. acuta.The constituents of the active fraction from this plant (GAHN) are systematically investigated.7 compounds are obtained by means of HPLC and various kinds of column chromatography including silica gel, Sephadex LH-20, C-18, and so on. The structures of these compounds are fully elucidated on the basis of MS, ID and 2D-NMR and physical properties, which are identified as 5 xanthons,2 flavonoids. The structures of xanthones are identified as demethylbellidifolin (1), mangiferin (2), bellidifolin (3), swertianolin (6), norswertianolin (7). The structures of flavonoids are identified as isovitexin (4) and isoorientin (5). Among all the isolated compounds, compound 4 is isolated from this plant for the first time.A model of H2O2-induced injury in H9c2 cardiomyoblasts was established. The cardioprotective effects of GAHN were evaluated by measuring the viability of the GAHN pretreated H9c2 cardiomyoblasts after exposure to H2O2-induced damage. We discussed the protective effects of GAHN against H2O2-induced injury in H9c2 cardiomyoblasts. The results showed that GAHN could significantly reduce the H2O2-induced damage to H9c2 cardiomyoblasts with a dose-dependent, and it could significantly decrease the levels of LDH leakage. Pretreated with GAHN could significantly improve the activity of endogenous antioxidant enzymes such as SOD, CAT, GSH-Px.The antioxidative activity of GAHN is evaluated by four different methods (DPPH-, ABTS, pyrogallol autooxidation and phenanthroline). And the IC50 values of four radicals are calculated. The results showed that GAHN exhibit strong activity of scavenging DPPH-, ABTS+, O2’- and OH with IC50 values are 22.5,9.5,18.7,32.9 mg/L, respectively.Ischemia/reperfusion protocol was carried out ex vivo using langendorff perftision method and the cardiac functional recovery was assessed in terms of percentage rate pressure product. GAHN was administered orally to rats daily for consecutive 7 days. The results indicated that GAHN (200.0,400.0 mg/kg) significantly increase the recovery of rat-pressure product (RPP), intraventricular pressure maximum upstroke and downstroke velocity (± dp/dtmax) compared with model group. Coronary effluents of LDH and CK-MB activities were evaluated. Pretreatment with GAHN decreased CK-MB and LDH levels compared with rats in model group in a dose-dependent manner. Compared with control group, the level of MDA was increased and the activities of SOD, GSH-Px, CAT were decreased in the model group. Administration of GAHN significantly decreased the level of MDA and increased the activities of SOD, GSH-Px, CAT in left ventricles compared with the model group. HE staining showed that heart globe ischemia/reperfusion treatment caused severe injury to the myocardial tissue, and GAHN observably decrease the myocardial tissue injury. The level of ATP and the activity of TCA cycle enzymes in the heart mitochondria were evaluated. The results indicated that pretreatment with GAHN increase the level of ATP and the activity of TCA cycle enzymes compared with model group. This study concluded that GAHN provides a profound protection against myocardial I/R injury.The model of normobaric hypoxia tolerance in mice was established. The mice was given isoprenaline 20.0 mg/kg (ip) and the survival time of the mice under hypoxic condition was recorded. The effects of total ethanol extraction (GAH) and different polarity fractions of G acuta (GAHW, GAHT, GAHS, GAHN) on hypoxia tolerance in mice were observed and recored. The results showed that GAH and 30% ethanol extraction (GAHT) prolong the survival time in mice under the hypoxic condition.This paper preliminarily clarifies the effective material basis of G. acuta for the treatment of CAD. That will provide essential foundation for developing new drugs against myocardial ischemia. Our works are very important in ensuring people’s usage safety and adequately developing this medical resource. |
PDF Full Text Request