目的 研究番茄红素对大鼠肺缺血再灌注损伤的保护作用, 并考察其作用机制。方法 取120只SD大鼠随机分为假手术组、模型组、舒血宁注射液(4 mg/kg)组以及番茄红素5、10、20 mg/kg组, 每组20只。除假手术组外采用夹闭左肺门45 min后松夹的方法制备大鼠肺缺血再灌注损伤模型。再灌注2 h后, 分别测定各组大鼠肺组织湿质量/干质量比值;通过苏木精-尹红(HE)染色观察肺组织病理学改变;原位末端标记(TUNEL)法观察肺组织细胞凋亡并计算凋亡指数(AI);检测血清中丙二醛(MDA)含量和髓过氧化物酶(MPO)活性;测定肺组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性。结果 与模型组比较, 番茄红素10、20 mg/kg组肺组织湿质量/干质量比值显著降低(P<0.05、0.01), 肺组织病变显著改善, 肺组织细胞凋亡状况明显改善;血清中MDA含量和MPO活性显著降低(P<0.05、0.01), 肺组织中SOD、CAT活性显著升高(P<0.05、0.01)。其中番茄红素20 mg/kg组对肺缺血再灌注损伤大鼠肺组织病变改善最为显著、细胞凋亡状况改善以及凋亡指数降低效果最为显著, 对血清中MDA含量和MPO活性显著降低效果更加显著、肺组织中GSH-Px活性显著升高(P<0.01)。结论 番茄红素能够有效降低肺组织湿质量/干质量比值, 改善肺组织病变, 抑制肺组织细胞凋亡、降低凋亡指数, 提示番茄红素对大鼠肺缺血再灌注损伤具有剂量相关性的保护作用, 其作用机制可能与番茄红素能够有效改善机体抗氧化酶活性、抑制氧化应激损伤有关。

Objective To investigate the protective effects of lycopene on pulmonary ischemia-reperfusion injury in rats and to explore its mechanism. Methods A total of 120 SD rats were randomly divided into Sham group, model group, Shuxuening Injection (4 mg/kg) group, and lycopene (5, 10, and 20 mg/kg) groups, and each group had 20 rats. Pulmonary ischemia-reperfusion injury models in rats except Sham group were clipped the hilum of left lung, and after 45 min release of the clip. Two hours after reperfusion, wet weight/dry weight ratios of lung tissue were determined, the histopathological changes of lung tissue were observed by HE method, myocardial apoptosis of lung tissue was observed by TUNEL method, and the apoptosis index (AI) was analyzed. At the same times, the contents of Malondialdehyde (MDA) and activity of myeloperoxidase (MPO) in serum were determined, the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in lung tissue were determined. Results Compared with the model group, indexes of lycopene (10, 20 mg/kg) groups such as wet weight/dry weight ratios were significantly decreased (P < 0.05, 0.01), histopathological changes and cells apoptosis of lung tissues were significantly improved, the content of MDA and activity of MPO in serum were significantly decreased (P < 0.05, 0.01), and the activity of SOD and CAT in lung tissue were significantly increased (P < 0.05, 0.01). Especially lycopene (20 mg/kg) group had better effects in improvement of histopathological changes, cells apoptosis, and AI, decrease of the content of MDA and activity of MPO in serum, and rise of activity of GSH-Px in lung tissues (P < 0.01). Conclusion Lycopene could effectively lower wet weight/dry weight ratio, improve the histopathological changes, inhibit lung tissue apoptosis, and lower the AI. It is suggested that lycopene has dose-dependent protective effects on pulmonary ischemia-reperfusion injury in rats, which perhaps related to its effects of improving antioxidant ability and inhibiting the oxidative stress.