寒冷暴露联合咪喹莫特诱导的小鼠银屑病样病变模型构建及开玄解毒核心方的疗效评价OA

Objective:To establish the mouse models of psoriasis-like lesions induced by continuous cold exposure or intermittent cold exposure combined with imiquimod(IMQ),and to evaluate the interventional effects of Kaixuan Jiedu core prescription(KXJD)on the two models.Methods:Male C57BL/6J mice were selected and classified into two experimental batches.The first batch of 36 mice was randomized into a room temperature group,a continuous cold exposure(10℃/24 h)group,and an intermittent cold exposure(10℃/6 h)group.Each group was further divided into a normal subgroup and a model subgroup(topical application of IMQ to induce skin lesions),with 6 mice in each subgroup,for modeling and evaluation.The second batch of 54 mice,with 6 in each group,were subjected to the same temperature grouping with an additional KXJD(30.42 g·kg-1,continuous gavage for 5 days)group.Comprehensive evaluation of model characteristics and KXJD efficacy was conducted through Psoriasis Area and Severity Index(PASI)scoring,skin temperature measurement by infrared thermography,histopathological observation by hematoxylin-eosin(HE)staining,detection of vascular endothelial growth factor(VEGF)and platelet endothelial cell adhesion molecule 1(CD31)by immunohistochemistry,detection of Claudin-1 and Occludin by immunofluorescence assay,determination of serum levels of tumor necrosis factor-α(TNF-α)and interleukin(IL)-10 by enzyme-linked immunosorbent assay(ELISA),and quantification of mRNA levels of IL-17A,IL-23,IL-6,and chemokine ligand 20(CCL20)in skin lesions by quantitative Real-time polymerase chain reaction(Real-time PCR).Results:Model mice in all temperature groups exhibited typical psoriasis-like skin lesions.Compared with the normal groups,the model groups showed increased PASI scores,decreased skin temperatures(P<0.05),obvious epidermal thickening,parakeratosis,and dermal inflammatory cell infiltration,as well as elevated mRNA levels of IL-17A,IL-23,IL-6,and CCL20(P<0.05).Cold exposure further aggravated psoriasis.The total PASI score of the intermittent cold exposure model group was higher than that of the room temperature model group(P<0.05).The serum IL-10 did not show a compensatory elevation,and the blood vessels presented a characteristic of elevated CD31 expression(P<0.05)without a synchronous increase in VEGF.The continuous cold exposure model group exhibited more significant dermal capillary tortuosity and dilation,with the highest mRNA levels of IL-17A,IL-23,IL-6,and CCL20 among all groups.Compared with the respective model groups,KXJD intervention alleviated skin lesions,reduced epidermal thickness and inflammatory cell infiltration,and increased skin temperature,with the temperature increase being particularly significant in the intermittent cold exposure+KXJD group(P<0.05).Furthermore,KXJD down-regulated the expression of VEGF and CD31,restored the expression of Claudin-1 and Occludin,decreased the mRNA levels of IL-17A and IL-23(P<0.05),and reduced the serum TNF-α level.Conclusion:This study successfully established compound psoriasis-like mouse models induced by cold exposure combined with IMQ.It confirms that cold aggravates the severity of psoriasis by exacerbating the closure of Xuanfu(sweat pores),microcirculation disorders,and immune imbalance.Moreover,different cold exposure patterns have distinct mechanism differences.Continuous cold exposure focuses on enhancing the inflammatory response via the IL-23/IL-17 axis and angiogenesis,simulating chronic aggravation under a long-term cold environment.Intermittent cold exposure tends to impair immune regulation and induce microvascular endothelial stress,corresponding to acute exacerbations caused by sudden temperature drops.KXJD can effectively alleviate psoriasis-like skin lesions under cold conditions by unblocking Xuanfu,regulating vasomotor function,and correcting abnormal immune-inflammatory responses.