ABSTRACT
ObjectiveThis study observes the intervention effect of Longmu Piyan prescription on oxidative stress in BALB/c mice with atopic dermatitis （AD） induced by 2，4-dinitrochlorobenzene （DNCB） and explores its mechanism. MethodThe AD model was established using the method of DNCB sensitization on the back skin of BALB/c mice. Forty male BALB/c mice were randomly divided into a blank group， a model group， a vitamin C control group （0.5×10-3 mg·kg-1）， and a Longmu Piyan prescription group （26 g·kg-1）. Except for the blank group， other groups were sensitized with different concentrations of DNCB on the back to induce AD， and the blank group was treated with matrix coating. The gastric administration was started on the seventh day after sensitization with 2% DNCB and on the 24th day after sensitization with 0.2% DNCB continuously for 21 days. The changes in skin lesions of each group were directly observed after the experiment. Enzyme-linked immunosorbent assay （ELISA） was used to detect the levels of interleukin （IL）-4， tumor necrosis factor （TNF）-α， immunoglobulin E （IgE）， and reactive oxygen species （ROS） in the serum of each group. The total antioxidant capacity determination kit-trace method (ABTS method) was used to measure the level of total antioxidant capacity （TAOC） in serum. The Hematoxylin eosin （HE） staining method was used to observe the pathological and morphological changes of the skin lesion site. The immunohistochemical method was used to detect the expression of thymic stromal lymphopoietin （TSLP） in the skin lesion site. Western blot was used to detect the expression of filaggrin （FLG） in the dorsal skin lesions. ResultThe results showed that compared with the blank group， the skin lesion score of the model group mice was significantly increased （P<0.01）， and HE staining showed characteristic pathological changes of AD in the skin lesion site. At the same time， the expression of TSLP in the skin lesion was significantly increased， and that of FLG was reduced （P<0.05）. The levels of TNF-α， IL-4， IgE， and ROS in serum increased， while the activity of TAOC decreased （P<0.01）. Compared with the model group， the Longmu Piyan prescription group showed a significant decrease in skin lesion scores and a significant improvement in skin lesion pathology. At the same time， the expression of TSLP decreased， and the expression of FLG increased in the skin lesions （P<0.05）. In addition， compared with the model group， the serum levels of TNF-α， IL-4， IgE， and ROS also decreased to varying degrees （P<0.05，P<0.01）， and TAOC activity increased in the Longmu Piyan prescription group （P<0.01）. ConclusionThere is a significant correlation among the degree of oxidative stress， the severity of skin lesions in AD， and the levels of inflammatory cytokines. Longmu Piyandu prescription can improve AD-like skin lesions in BALB/c mice by promoting ROS clearance， enhancing TAOC， and inhibiting oxidative stress， thus protecting the skin barrier and reducing inflammation.