Effect Of Radix Hedysari Water Extract On TNF-α, IL-10and NF-κBp65in Lipopolysaccharide Induced Acute Lung Injury Rats

Objective: To observe the effect of Radix Hedysari water extract on the morphology oflung tissue, and on immune functions and NF-κBp65pathway in ALI rats, investigate itsrelated therapeutic mechanism, in order to provide experimental basis for the clinicalapplication of Radix Hedysari in the treatment ofALI.Methods:60SPF Wistar rats,180~220g, half male and half female, were randomizedinto normal control group (10rats) and model group (50rats). The rats in the model groupwere intraperitoneally injected LPS5ml·kg-1to make ALI model. After model making, therats were randomized into: model group (M group), Radix Hedysari water extract treatmentgroups (high, middle, low dose group), positive control group (dexamethasone group, DEXgroup),10rats in each group. After4h modeling, Radix Hedysari water extract of high,middle, low dose group were intragastricly given5.2g·kg-1,2.6g·kg-1,1.3g·kg-1respectively;the rats of DEX group were given0.01g·kg-1; NS group and M group rats were given the samevolume of NS orally,1time a day for3days.24h after the last administration, all the rats were sacrificed, and the lungs were weighted.The left lungs were weighted, drying for48h at60℃; middle lobes of the right lungs werefixed in4%formalin, then embedded with paraffin. Continuous4μ m thick slices wereacquired. The remaining lung tissue were restored at-80℃refrigerator. Lung index (LI), leftlung wet/dry weight ratio (W/D) and lung water rate were calculated. Lung pathologicalmorphology was observed under optical microscope; the expression of TNF-α and IL-10protein were detected with immunohistochemical SP method; the expression of lung tissueNF-κBp65（rela） mRNA and mapk14mRNA were detected by real-time fluorescentquantitative PCR.Results:1.After the application of LPS, the breath were quickened and deepened, piloerection,stooping, lips cyanosis, cough, lethargy, poor appetite and other symptoms, indicating the success of modelling.2.LI, W/D and lung water content rate in M group were increased, in NS group, high,medium, low dose groups of Radix Hedysari water extract and DEX group decreased.3.Under light microscopy, alveolar structure in NS group was clear, with no obviousinflammatory cell infiltration and exudation; in M group, there focal pulmonary hemorrhage,pulmonary interstitial and alveolar edema, alveolar wall thickening, alveolar collapse,peripheral vascular and bronchial inflammatory cell infiltration; in DEX group, lung tissuewas clear, less damage, pulmonary congestion and edema, inflammatory cell infiltrationphenomenon obviously reduced or disappeared; in high dose water extract group, lung tissuestructure was clear, alveolar interval narrowed, less red blood cell and neutrophil exudation,and lung injury improved significantly; in middle and low dose groups, rats alveolarhemorrhage degree, number of alveolar edema and inflammatory cells were less than that inthe M group.4.The expression level of TNF-α protein in M group increased significantly; in treatmentgroups, TNF-α expression level decreased significantly; DEX group and low dose group ofRadix Hedysari water extract got about the same effect; high, middle dose groups wassuperior to low dose group.5. IL-10protein in lung tissue decreased in M group, increased in each treatment group;high, medium dose group got about the same expression level with DEX group.6.Expression quantity of NF-κBp65（rela）mRNA, mapk14mRNAwere significantlyincreased in M group, decreased in the treatment groups.Conclusions:1.Radix Hedysari water extract in each treatment group can improve the morphologicalchanges, such as pulmonary edema, hemorrhage, decrease LI, W/D and the pulmonary waterratio ofALI rats.2.Radix Hedysari water extract high, middle dose group can inhibit TNF-α and enhanceIL-10protein expression in the lung tissue ofALI rats.3.Radix Hedysari water extract treatment group could inhibit NF-κBp65（rela）mRNA,mapk14mRNAgene expression in the lung tissue ofALI rats. Protective effect of Radix Hedysari on ALI rats may be through the promotion of IL-10expression, the inhibition of TNF-α expression and p38MAPKs signaling pathway, therebypreventing the activation of NF-κB pathway.