红豆杉多糖对Beagle犬心肌缺血再灌注损伤模型心肌NADPH氧化酶mRNA及SOD、MDA的影响

目的观察红豆杉多糖对心肌缺血-再灌注损伤(MIRI)模型心肌损伤及心肌还原型辅酶II(NADPH)氧化酶mRNA、超氧化物歧化酶(SOD)、丙二醛(MDA)的影响。方法将30只Beagle犬随机分为假手术组、模型组、红豆杉多糖低剂量组与高剂量组、卡维地洛对照组,每组6只,给药7 d后,建立MIRI模型。HE染色,光镜观察心肌组织病理改变;原位杂交检测NADPH氧化酶p47phox(NCF-47K)mRNA表达;比色法检测心肌SOD活性和MDA水平。结果光镜下可见,模型组心肌严重紊乱、断裂,核固缩及胞浆嗜酸性变明显,轻至中度充血、水肿,炎细胞浸润;红豆杉多糖高剂量组心肌细胞紊乱、断裂程度较轻,核固缩及胞浆嗜酸性变明显减少,部分组织仍有轻度充血、水肿。模型组、红豆杉多糖低剂量组心肌NCF-47K mRNA表达较假手术组显著升高(P<0.01),红豆杉多糖高剂量组NCF-47K mRNA表达显著低于模型组(P<0.05)。除红豆杉多糖高剂量组心肌SOD活性显著高于模型组(P<0.01)外,模型组及各治疗组心肌组织SOD活性较假手术组显著降低(P<0.01)。模型组及红豆杉多糖低剂量组心肌组织MDA水平较假手术组显著增加(P<0.05),红豆杉多糖高剂量组心肌MDA水平显著低于模型组(P<0.05)。结论红豆杉多糖可能通过降低心肌组织NADPH氧化酶NCF-47K mRNA表达,升高SOD活性,减少O2÷等氧自由基对心肌细胞的损伤,减轻缺血再灌注导致的心肌损伤。

Effects of Taxus polysaccharide on myocardial NADPH oxidase mRNA, and SOD, and MDA in myocardial ischemia-reperfusion injury model of Beagle's dogs

Objective To investigate the influence of Taxus polysaccharide on myocardial NADPH oxidase mRNA, SOD, and MDA in myocardial ischemia-reperfusion injury (MIRI) model of Beagle's dogs. Methods Beagle's dogs (30) were randomly divided into Sham operation, model, low-dose Taxol polysaccharide, high-dose Taxol polysaccharide, and Carvedilol groups, six in each group, and MIRI model was established after 7 dadministration. Stained with HE, pathological changes in myocardial tissue were observed with light microscopy; NADPH oxidase p47phox (NCF-47K) mRNA expression was detected with in situ hybridization; Myocardial SOD and MDA contents were detected with colorimetry. Results Under light microscope, serious cardiac cells disorders, fracture, karyopyknosis, and significant eosinophilic cytoplasm existed, mild to moderate hyperemia and edema and inflammatory cell infiltration appeared in the model group. However, in the high-dose group, myocardial cells disorders and destruction existed in a lesser extent, karyopyknosis and eosinophilic cytoplasm decreased ignificantly, and some organizations were still mild hyperemia and edem. Myocardial NCF-47K mRNA expression of Beagle's dogs in the model group and low-dose group were significantly higher than that in the Sham-operated group (P<0.01), NCF-47K mRNA expression of Beagle's dogs in the high-dose group was significantly lower than that in the model group (P<0.05). And SOD content in myocardial tissue of the model group and the treatment group was significantlylower than that in the Sham-operated group (P<0.01). SOD content in the high dose group was significantly higher than that in the model group (P<0.01). MDA contents in myocardial tissue in the model and low-dose groups were significantly higher than those in the Sham-operated group (P<0.05). MDA content in high-dose group was significantly lower than that in the model group (P<0.05). Conclusion The Taxus polysaccharide may reduce ischemia-reperfusion myocardial injury by reducing the expression of NADPH oxidase,increasing SOD activity, and reducing injury of O2÷ and other oxygen free radicals in myocardial cell.