| Sepsis is an uncontrolled inflammatory reaction in the host caused by a severe infection,which can easily cause multiple organ dysfunction.The lung is one of the organs most commonly involved.Sepsis patients with acute lung injury(ALI),and even those with hypoxemia that are difficult to treat,have a mortality rate of up to 43%.Autophagy,the body’s self-defense mechanism,can swallow and digest damaged organelles,and maintain cell homeostasis.Up-regulation of autophagy can play a protective role against lung injury in septic rats.Carbazochrome sodium sulfonate is a capillary stabilizer,which can improve capillary elasticity and reduce pulmonary vascular exudation.However,whether it is beneficial to alleviate the changes in lung permeability caused by sepsis,induce autophagy activation,and thus protect lung tissue remains to be studied.The rats were randomly divided into: sham operation group,sepsis group,low-dose carbazochrome sodium sulfonate group(8mg/kg),medium-dose group(40mg/kg),and high-dose group(80mg/kg).There were twenty five rats in each group.Out of them,fifteen rats were used for survival rate monitoring(72 hours),and ten rats were used to detect the effect of carbazochrome sodium sulfonate on lung morphology and function in septic ALI.The sepsis model was established by the cecal ligation and puncture(CLP)method.Immediately after the operation,at 8h and 16 h postoperatively,carbazochrome sodium was injected into the abdominal cavity per groups,and 0.9% Na Cl was injected in the sham operation and sepsis groups.At the same time,0.9% Na Cl was injected into rats of sham and sepsis group.In order to clarify the relationship between the therapeutic effect of carbazochrome sodium sulfonate and autophagy,twenty rats were randomly divided into the carbazochrome sodium sulfonate medium-dose group(40mg/kg)and the autophagy inhibitor3-methyladenine group(3-MA).In the middle-dose group of carbazochrome sodium sulfonate,carbazochrome sodium sulfonate(40mg/kg)was injected intraperitoneally at 0.5h,8h,and 16 h after operation.The 3-MA group was given 3-MA(15 mg/kg)immediately after operation,the carbazochrome sodium sulfonate(40mg/kg)was given intraperitoneally at 0.5h,8h,and 16 h postoperatively.After the operation,pay close attention to the physical signs of the rats,including: mental status,free movement ability,diet,response to sound stimulation,breathing rate,whether or not the rat is shivering,etc.,and draw the 72 h rat survival curve.Twenty-four hours after surgery,arterial blood was tested for blood gas;lung Micro-CT was performed;both lungs of rats were weighed,and lung coefficient was calculated based on the ratio of body weight(mg/g);lung tissue Evans blue extraction method was used to detect capillary permeability;HE staining was performed to observe lung tissue changes;Western-blot method showed changes in the ratio of LC3-Ⅱ/LC3-Ⅰ in lung tissue.Compared with the sham operation group,the sepsis group had poorer spirits,lethargy,less activity,decreased diet,low voice stimulation,shallow breathing,and piloerection.Compared with the sepsis group,the rats in the carbazochrome sodium sulfonate group have better spirits,better mobility,better diet,turn head response to sound stimulation,smoother breathing,better chills and piloerection,and 40mg/kg,80mg/kg carbazochrome sodium sulfonate group is better than 8mg/kg group.The general state of the rats in the 3-MA group was worse than that in the 40mg/kg carbazochrome sodium sulfonate group.In the 72-hour survival rate,the survival rate of rats in each group of carbazochrome sodium sulfonate increased.The arterial partial pressure of oxygen and oxygenation index in each group of carbazochrome sodium sulfonate increased compared with the sepsis group at 24 hours after operation(P<0.01).The lung coefficient and pulmonary vascular permeability of the 40mg/kg and 80mg/kg groups were correlated with those in the sepsis group.Compared with the sepsis group,they all decreased(P<0.05).Lung imaging and lung HE staining showed that the lung lesions and injuries were more severe in the sepsis group,while the degree of lung lesions and injuries in each group of carbazochrome sodium sulfonate was lessened(P<0.05).Western-blot results showed that the ratio of LC3-Ⅱ/LC3-Ⅰ in the sepsis group was higher than that in the sham operation group(P<0.05),and the 8mg/kg,40mg/kg carbazochrome sodium sulfonate group was higher than that in the sepsis group.The ratio of LC3-Ⅱ/LC3-I further increased(P<0.05).Compared with the middle-dose carbazochrome sodium sulfonate group,the value of LC3-Ⅱ/LC3-Ⅰ in the lung tissue of rats in the 3-MA group was significantly reduced,and the difference was statistically significant(P<0.05).In summary,carbazochrome sodium sulfonate can reduce lung capillary leakage and improve oxygenation and reduce ALI.Also,survival rate of sepsis rats is improved.There is a certain correlation between the efficacy and the dose concentration.Carbazochrome sodium sulfonate can reduce ALI in septic rats by up-regulating the level of autophagy in lung tissue,which may be one of the mechanisms of action. |
PDF Full Text Request