| Objective : To study the effects of RSV-induced dendritic cell autophagy on inflammatory cytokines in asthmatic mice,so as to reveal the formation mechanism of phlegm accumulation and scientifically explain the theory of phlegm accumulation.From intervening the effects of virus-induced dendritic cell autophagy on inflammatory cytokines in asthmatic mice,this paper explores the possible ways of Wuhu Decoction influencing the formation of asthma "futan" and provides theoretical and experimental basis for further elucidating the mechanism of Wuhu Decoction in the prevention and treatment of asthma.Methods:160 SPF Bal B/C mice were randomly selected as blank group and 130 as model group.The asthma model was established by RSV combined with OVA sensitization.After 14 days of sensitization,10 mice were randomly selected from blank group and model group to judge whether the model was successful by observing the behavior of mice and detecting airway hyperresponsiveness.The mice were divided into 6 groups according to the random number table method,20 mice in each group,namely model group,positive control group(dexamethasone),rapamycin group(autophagy inducer),low-dose Wuhu Decoction group,medium-dose Wuhu Decoction group and high-dose Wuhu Decoction group.In addition to 20 mice in the blank group,the other six groups were given drug intervention according to the grouping situation: Wuhu Decoction low,medium and high dose groups were given Wuhu Decoction by intragastric administration(5 ml/kg of low dose,10 ml/kg of medium dose and 20 ml/kg of high dose according to the observation results of clinical dose-effect relationship),and intraperitoneal injection of saline(10 ml/kg);dexamethasone(1.82 mg/kg)by intraperitoneal injection in the positive control group,and intragastric administration,etc.Volume normal saline;Rapamycin group was intraperitoneally injected with rapamycin(1mg/kg)and intragastrically administered with equal volume normal saline;blank group and model group were intragastrically administered with equal volume normal saline.After 14 consecutive days,blood and lung tissues were taken for autophagy examination by transmission electron microscopy.Western Blot method was used to detect the expression of autophagy marker proteins LC3 I,LC3 II and Beclin 1.LC3 II/LC3 I ratio was calculated.The serum levels of IFN-gamma,IL-4,IL-10 and IL-13 were determined by ELISA,and the IFN-gamma/IL-4 ratio was calculated.Results :(1)The clinical manifestations of irritability,nose scratching and nodding breathing of mice in each dose group of Wuhu Decoction and dexamethasone group were improved in varying degrees after treatment,especially in the middle dose group of Wuhu Decoction.(2)The airway resistance of model group mice was higher than that of blank group at acetylcholine concentration of 6.25 mg/ml,12.5 mg/ml,25 mg/ml and 50mg/ml,and the difference was statistically significant.(P < 0.01).(3)LC3 2/1 ratio and Beclin 1 value: The model group was higher than the blank group,the difference was statistically significant(P < 0.05);the three dosage groups of Wuhu Decoction were higher than the model group,the difference was statistically significant(P < 0.05);the model group was higher than the blank group,the difference was statistically significant(P < 0.05);the LC3 2/1 ratio of rapamycin group was significantly different from the Wuhu Decoction group and the model group,respectively.The LC3 2/1 ratio of rapamycin group was the highest,and there was no significant difference between dexamethasone group and model group(P >0.05).(4)IFN-gamma level: the model group was lower than the blank group,the difference was statistically significant(P < 0.05);the three dose groups of Wuhu Decoction were higher than the model group,the difference was statistically significant(P < 0.05),and the middle dose group of Wuhu Decoction was higher than the high dose group of Wuhu Decoction and the low dose group of Wuhu Decoction;the dexamethasone group was more unified than the middle dose group of Wuhu Decoction and the low dose group of Wuhu Decoction.The difference was between them(P < 0.05).(5)IL-4 level: Compared with the three dosage groups of Wuhu Decoction,dexamethasone group and blank group,the model group increased significantly(P <0.05);the three dosage groups of Wuhu Decoction increased slightly compared with the blank group,the difference was statistically significant(P < 0.05),among which the low dosage group of Wuhu Decoction increased most significantly,followed by the high dosage group of Wuhu Decoction;the middle dosage group of Wuhu Decoction had no significant difference compared with the dexamethasone group.(P > 0.05).(6)IFN-gamma/IL-4 ratio: There was no significant difference between the blank group and the middle dose group and the dexamethasone group(P > 0.05);the three dose groups and the dexamethasone group were higher than the model group(P< 0.05),and the difference was significant(P < 0.05),among which the middle dose group of Wuhu decoction was the most significant.(7)IL-10 level: The model group was lower than other groups,the difference was statistically significant(P < 0.05);the middle dose group of Wuhu Decoction was significantly higher than the low dose group and the high dose group of Wuhu Decoction(P < 0.05),and the middle dose group of Wuhu Decoction was the most significant increase(P < 0.05).(8)IL-13 level: Compared with the other six groups,the model group increased significantly(P < 0.05),and the model group increased most significantly.The middle dose group of Wuhu Decoction decreased significantly compared with the low dose group,the high dose group,the dexamethasone group and rapamycin group(P <0.05).Conclusion:1.RSV can induce the increase of autophagy level of dendritic cells in lung tissue of asthmatic mice,increase the levels of IL-4 and IL-13,decrease the levels of IFN-gamma and IL-10,and mediate chronic airway inflammation.2.Wuhu Decoction can reduce the levels of IL-4 and IL-13 in serum of asthmatic mice,increase the levels of IFN-gamma and IL-10,improve airway inflammation and exert the therapeutic effect of asthma.The middle dose group of Wuhu Decoction has the best effect.3.Wuhu Decoction can enhance the autophagy level of dendritic cells in lung tissue after RSV infection,and its advantages and disadvantages need further study. |
PDF Full Text Request