Protective Effect Of Procyanidins On Injury Of Rat Abdominal Aorta Induced By PM_2.5 And Its Mechanism

Objective:To observe the injury of fine particles to abdominal aorta and the protective effect of Procyanidins,SD rats were used to establish a fine particle injury model,and Procyanidins were used as an intervention?On the basis of the above–mentioned,the potential mechanism is discussed to provide scientific basis for preventing cardiovascular injury caused by air pollution from the perspective of diet.Method:Fifty healthy male SD rats were divided into five groups randomly.?1?control group:normaly feed without any treatment;?2?PM_2.5group:PM_2.5 tracheal instillation+distilled water gavage?3?Low dose Procyanidins intervention group:PM_2.5 tracheal instillation+50mg/kg Procyanidins gavage;?4?Intervention group of medium dose Procyanidins:PM_2.5tracheal instillation+100mg/kg Procyanidins gavage;?5?High dose Procyanidins intervention group:PM_2.5 tracheal instillation+200mg/kg Procyanidins gavage.Animals were fed for a total of 21 days,gavage is conducted every day;Blood pressure was measured on the 7th,14th and 21st days;Tracheal instillation was carried out on the 8th,10th and 12th days.After collecting abdominal aorta samples,HE staining was used for pathological examination;Tunel method was used to observe the apoptosis of blood vessels.The contents of SOD and MDA were determined by the kit.Western Blot was used to detect the expression and content of related proteins.Data were expressed as?x±SD.One-way ANOVA test was performed on SPSS 21.0 software.LSD-t method was used for comparison between the two groups.The level of significance adopted was P<0.05.Results:1. compared with the control group,the weight of PM_2.5 group and each intervention group significantly decreased at the end of the experiment,with statistical difference?P<0.05?,and there was no difference in blood pressure between the groups.2. HE staining showed that the vascular morphology of each group was normal and no pathological changes occurred.3. Compared with the control group,SOD activity in abdominal aorta of PM_2.5group decreased significantly,while ROS and MDA production increased,and the difference between the two groups was statistically significant?P<0.05?.Compared with PM_2.5 group,SOD activity increased and ROS and MDA production decreased significantly after Procyanidins intervention?P<0.05?.4. There were few apoptotic cells in the control group,while the apoptosis rate in the PM_2.5 group significantly increased.Compared with PM_2.5 group,apoptosis rate decreased after Procyanidins intervention.5. Compared with the control group,the release of cytochromec from mitochondria,the ratio of Clevead-Caspase-3/Caspase-3 and the expression of Bax significantly increased in PM_2.5 group,while the expression of Bcl-2,Nrf2,HO-1 and NQO1 decreased,and the difference between the two groups was statistically significant?P<0.05?.Compared with PM_2.5 group,the release of cytochrome c from mitochondria,the ratio of Clevead-Caspase-3/Caspase-3,and the expression of Bax decreased,while the expression of Bcl-2,Nrf2,HO-1,and NQO1 increased significantly in Procyanidins groups,with statistically significant difference?P<0.05?.Conclusion:PM_2.5instillation can induce oxidative stress and apoptosis in rat blood vessels,but not pathological and blood pressure changes in rats.Procyanidins produce protective effect by activating Nrf2/HO-1 pathway,and reduce the damage caused by PM_2.5.