Studys On Anti-Inflammatory Effects And Mechanisms Of Yulangsan

Objective:To study the anti-inflammatory effect and its mechanisms of Yulangsan(YLS)extracts(Yulangsan aqueous extract and flavonoid).It will provid experimental evidence and theoretic basis for the further development of YLS.Methods:1.The models of acute inflammation in mice such as dimethylbenzene-induced ear swelling,carrageenan-induced hind paw edema and trauma-induced toe congestion were performed to investigate the effects of YLS extracts.The levels of prostaglandin E₂(PGE₂)and nitric oxide(NO)in the inflammatory tissue were detected then.2.To explore the relationship between the anti-inflammation of YLS extracts and hypothalamus-pituitary-adrenal axis (HPAA),the model of dimethylbenzene-induced ear swelling in bilaterally adrenalectomized mice was performed,meanwhile,the contents of Vit C and cholesterol in normal adrenal glands and serum cortisol were measured after given the drugs in rats.3.The effect of YLS extracts on inflammatory mediators and other parameters was assessed by the rat model of carrageenan-induced pleurisy.The volume of pleurorrhea,the amount of leucocyte,the contents of protein,PGE₂,NO,malondialdehyde(MDA),tumor necrosis factorα(TNF-α), the activities of superoxide dismutase(SOD)and myeloperoxidase(MPO)in the pleurorrhea were measured respectively.4.To study the effects and the mechanisms of YLS extracts on yeast suspension-induced acute lung injury (ALI),the content of interleukin-1β(IL-1β)in the lung tissue was detected by enzyme-linked immunosorbnent assay(ELISA),the expression of nuclear factor-κB(NF-κB)was analyzed by immunohistochemistry,meanwhile, pathology changes of lung tissue,the lung wet/dry weight ratio and the activity of MPO in the lung tissues were determined.Results:1.The aqueous extract(YLSA)and flavonoid(YLSF)of Yulangsan showed a marked suppressive effect on the ear swelling induced by dimethylbenzene,the normal mouse hind paw edema induced by carrageenan, the toe congestion in mice and the synthesis of PGE₂ in the injected paw of mice caused by carrageenan in a dose-dependent manner(P＜0.05),but they couldn't inhibite the synthesis of NO in the exudates(P＞0.05).2.High dosage of YLSA and YLSF could significantly decrease the contents of Vit C and cholesterol in normal adrenal glands,and increase the content of serum cortisol in rats significantly(compared with control group,P＜0.05).In addition,YLS extracts couldn't inhibit the ear swelling caused by dimethylbenzene in adrenalectomized mice,just appearing the trend of reduction(P＞0.05).3.The results showed that YLSA and YLSF could reduce the pleurorrhea volume,leukocyte count,protein, PGE₂,MDA and TNF-αcontents,and MPO activity,and increase SOD level in the pleurorrhea as compared with the model group.In addition,they had not apparent inhibitive effects on the content of NO in the pleurorrhea(P＞0.05).4. As compared with the model group,YLSA and YLSF could lessened the degree of the lung injury,decreased IL-1βcontent,reduced MPO activity and the lung wet/dry weight ratio,downregulate the expression of NF-κB(P＜0.05).Conclusion:The YLS extracts have the inhibitive effects on the acute inflammation,which mechanisms may be related to their effects of suppressing the infiltration and transmigration of leucocytes,decreaseing the exudation, attenuating free radicals,inhibiting the synthesis of inflammation mediator PGE₂, reducing the contents of TNF-αand IL-1βby interfering the NF-κB path and activating the hypothalamus-pituitary-adrenal axis.