Improvement of Skin Barrier and Anti-inflammatory Mechanism of Huangliansan on Atopic Dermatitis in Mice / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo explore the therapeutic effect of Huangliansan on atopic dermatitis （AD） model mice induced by 2， 4-dinitrochlorobenzene （DNCB）. MethodA total of 42 male BALB/c mice were randomly divided into normal group， model group， hydrocortisone group， low， medium， and high-dose groups （0.3， 0.6， 1.2 g·kg-1） of Huangliansan oil， and water extract group （0.6 g·kg-1） of Huangliansan. In addition to the normal group， DNCB was applied on the back of mice in other groups to establish the AD model. On the 15th day after DNCB stimulation， each group was given the corresponding drug or solvent， and the changes in skin lesions， dermatitis score， and frequency of scratching were observed and recorded. Hematoxylin-eosin （HE） staining was used to observe the histopathological changes in the skin and spleen. Real-time fluorescent quantitative polymerase chain reaction （Real-time PCR） was used to detect mRNA levels of filaggrin （FLG）， lorophane （LOR）， and involucrin （IVL） in skin， as well as immunoglobulin E （lgE）， interleukin-4 （IL-4）， interleukin-6 （IL-6）， interleukin-1β （IL-1β）， tumor necrosis factor-α （TNF-α）， and interferon-γ （IFN-γ） in spleen. ResultCompared with the normal group， the model group showed symptoms of skin swelling and scab， and the score of dermatitis， the frequency of scratching， and the spleen index were increased （P<0.05）. The expression levels of FLG， LOR， and IVL in skin tissue were significantly decreased （P<0.01）， and the mRNA expressions of IgE， IL-4， IL-6， IL-1β， and TNF-α in the spleen were significantly increased， while the expression level of IFN-γ was significantly decreased （P<0.01）. Compared with the model group， the symptoms of skin erythema， scaly， and scab of mice in each drug group were alleviated to varying degrees， and the score of dermatitis， the frequency of scratching， and the spleen index were decreased （P<0.05， P<0.01）. In addition， the expression levels of FLG， LOR， and IVL in the skin of mice in the drug group were increased （P<0.05， P<0.01）， and the mRNA expression of IgE， IL-4， IL-6， IL-1β， and TNF-α in spleen were decreased. IFN-γ was increased （P<0.05， P<0.01）， and the lesions of the skin and spleen were improved to varying degrees. The medium-dose group of Huangliansan oil and hydrocortisone group had the most obvious manifestations （P<0.05， P<0.01）. The indexes in the medium-dose group of Huangliansan oil were better than those in the water extract group of Huangliansan. ConclusionHuangliansan may improve the expression level of skin barrier protein， inhibit the expression of helper T cell 2 （Th2）-related inflammatory factors， increase the expression of helper T cell 1 （Th1） inflammatory factors， restore the skin barrier function and Th1/Th2 balance in the spleen， regulate the inflammatory response in the spleen of AD mice， and thus relieve AD. Huangliansan oil is more effective than water extract.