A Study On The Influence And Mechanism Of Lactoferrin To Acute Lung Injury Induced By Oleic Acid In Rats

Objective：In order to explore ALI each index variation and potential linkages suchas wet/dry weight ratio of lung (W/D), arterial oxygen pressure (PaO2),theconcentration of serous8-isoprostanes,tumor necrosis factor (TNF-alpha) concentrationin serum and bronchoalveolar lavage fluid by means of detecting the changes of theseindexes and the law in ALI rats model induced by oleic acid. Lactoferrin was used tointervene ALI rat models induced by oleic acid(OA) for the purpose of understandingthe influence to each indexes and the influence mechanism of lactoferrin when ALI andwhether it has the preventive as well as therapeutical effect.Methods:32healthy SD rats were randomly divided into4groups:normalgroup,model group,LF prevent group in early(prevent group)and LF treatment grouptimely(treatment group)，8rats in each group. ALI animal models were established bymeans of intravenous injection of oleic acid (0.2ml/kg). Wet/dry weight radio of lungtissue and arterial partial pressure of oxygen(PaO2) were observed.Through the lightmicroscope to observe changes of lung tissue cells.The concentration of serous8-isoprostanes、 tumor necrosis factor (TNF-alpha) concentration in serum andbronchoalveolar lavage fluid were detected by means of double antibody sandwichmethod (ABC-ELISA). Then each index of the experimental data for statistical analysis.Results:1Compared with the normal group，the PaO2and PaO2/FiO2of model group,prevention group and treatment group were significantly reduced（P<0.05）,and the W/D ratio of Lung tissue were all increased compared with the normal group(P<0.05),there was lung injury performance in model group, prevention group andtreatment group. But compared with the model group, lung injury of prevention groupand treatment group had abated in degree, and there was no significant differencebetween prevention group and treatment group.2The tumor necrosis factor (TNF-alpha) concentration of Serum and bronchoalveolar lavage fluid (BALF) in model group, prevention group and treatmentgroup were increased compared with the normal group（P<0.05）,but compared with themodel group, the rate of increase were all low in prevention group and treatment group（P<0.05）, and there was no significant difference between prevention group andtreatment group（P>0.05）.3The8-isoprostanes concentration in model group, prevention group andtreatment group were all increased compared with the normal group（P<0.05）, andcompared with the model group, the rate of increase were all low in prevention groupand treatment group（P<0.05）, there was no significant difference between preventiongroup and treatment group（P>0.05）.4There is a clear linear relationship between the concentration of inflammatorycytokines TNF-alpha and8-isoprostanes.Conclusions:1By intravenous injection of oleic acid(0.2ml/kg),ALI rats models can besuccessfully reproduced.2There is a imbalance state of oxidation-antioxidant system when ALI.Therise of8-isoprostanes can reflect the enhanced oxidative stress,and the level of its canbe used as a reliable indicators reflecting disease severity.3There is a closely relationship between inflammation factors and oxidativestress in ALI rats models.,and there is possibly a positive feedback effect betweenthem.4Lactoferrin may have prevention protective effect and early treatment effect toacute lung injury (ALI).