黄芩苷对油酸所致急性呼吸窘迫综合征大鼠的作用

Effects of baicalin on oleic acid induced-acute respiratory distress syndrome in rats

目的验证中药黄芩苷的抗氧化能力以及对油酸所致急性呼吸窘迫综合征(ARDS)的改善作用。方法将雄性SD大鼠随机分为对照组、油酸组和黄芩苷低、中、高剂量(150、300、450 mg/kg)组,分别在染毒后10 min、1 h、2 h、6 h不同时间点采集动脉血测定氧分压(PaO_(2)),同时检测血常规、动脉血气分析、肺组织内髓过氧化物酶(MPO)和活性氧(ROS)等指标及进行组织病理学检查。结果染毒2 h时油酸组的氧合指数达到最低值(189.45±43.03)mmHg,符合ARDS的诊断(<200 mmHg),与对照组相比,P<0.01;黄芩苷中剂量组(治疗组)氧合指数改善最为明显。此外,油酸组大鼠WBC、中性粒细胞计数(N)和百分比(N%)与对照组相比,升高具有统计学意义,治疗组这些指标出现峰值的时间晚于油酸组;油酸组和治疗组大鼠肺组织ROS含量均高于对照组,但治疗组ROS峰值低于油酸组,6 h时接近对照组;MPO浓度具有相同的变化规律。HE染色和病理评分显示,治疗组肺损伤程度较油酸组轻。结论适宜剂量的黄芩苷可能通过减少中性粒细胞在肺内的集聚和ROS产生发挥抗氧化作用,进而改善ARDS的缺氧状态。

Objective To investigate the antioxidative capacity of a traditional Chinese medicinal material baicalin,and its improvement effect on oleic acid induced-acute respiratory distress syndrome(ARDS).Methods Healthy adult male SD rats were randomly divided into control group,oleic acid group and low,medium and high dose(150,300,450 mg/kg)of baicalin groups.Arterial blood samples of the rats were collected at different time points of 10 min,1 h,2 h and 6 h after oleic acid exposure for the detections of partial pressure of oxygen(PaO2),meanwhile,other related indicators such as blood routine,arterial blood gas,myeloperoxidase(MPO)and reactive oxygen species(ROS)in lung tissue,as well as the pulmonary histopathology.Results The results showed that after two hours of exposure to oleic acid,the oxygenation index of the rats reached its lowest value(189.45±43.03)mmHg,which is consistent with the diagnosis of ARDS(<200 mmHg),compared with the control group,P<0.01,the improvement of oxygenation index was most obvious in medium dose group of baicalin(treatment group).In addition,the WBC and neutrophil(N)counts as well as their percentage count of the rats in oleic acid group were statistically significant increased compared with those of the control group.The peak time of these indexes in treatment groups was later than that of the oleic acid group;while the ROS content in lung tissue of oleic acid rats and baicalin treated rats were all higher than that of control rats,but the peak value of ROS in baicalin treated rats was lower than that of oleic acid exposed rats,and almost lowered to the level of control rats at 6 h;the MPO concentration seemed to have the same pattern of variation.HE staining and pathological score showed that the degree of lung injury in the treatment group was milder than that of oleic acid rats.Conclusion The results suggested that appropriate dose of baicalin may exert good antioxidative effect by reducing the aggregation of neutrophils in the lungs and the production of ROS,thereby improving the hypoxic state of ARDS.