基于 FABP5/PPAR γ通路探讨固本祛湿化瘀方对脾虚湿阻型银屑病模型小鼠免疫及脂代谢的影响OA

Objective To investigate the effects and mechanisms of Guben Qushi Huayu Formula(GQHF)in ameliorating immune dysfunction and lipid metabolism disorders in a mouse model of psoriasis with spleen deficiency and dampness retention syndrome,based on the fatty acid-binding protein 5(FABP5)/peroxisome proliferator-activated receptor γ(PPARγ)pathway.Methods Forty-two BALB/c mice were randomly divided into a normal group,a psoriasis model group,a spleen deficiency and dampness retention syndrome group,a psoriasis with spleen deficiency and dampness retention syndrome model group,a methotrexate group(1.5 mg·kg-1),and high-dose(22.75 g·kg-1)and low-dose(11.34 g·kg-1)GQHF groups,with 6 mice in each group.The spleen deficiency and dampness retention syndrome model and psoriasis model were established using the internal dampness method and imiquimod induction,respectively.The psoriasis with spleen deficiency and dampness retention syndrome model was established by combining the internal dampness method with imiquimod induction.Concurrently,corresponding concentrations of drugs were administered by gavage for 10 consecutive days.Skin lesion changes were observed,and Psoriasis Area and Severity Index(PASI)scores,body weight,spleen coefficient,white adipose tissue coefficient,and serum levels of total cholesterol(TC),low-density lipoprotein cholesterol(LDL),aspartate aminotransferase(AST),alanine aminotransferase(ALT),and high-density lipoprotein cholesterol(HDL)were measured.HE staining was used to observe pathological changes in skin lesions and liver tissue.Serum levels of tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),interleukin-1β(IL-1β),interleukin-17A(IL-17A),and interleukin-4(IL-4)were detected by ELISA.mRNA expression levels of FABP5,CD36,and PPARγ in subcutaneous adipose tissue were measured by RT-PCR.Expression levels of CD4⁺ and CD4+IL-17A+T cells in spleen tissue were assessed by flow cytometry.Protein expression levels of FABP5,CD36,p-PPARγ,and PPARγ in skin tissue were detected by Western Blot.Results(1)In the normal group,the back skin tissue exhibited intact and well-defined epidermal structures with a thin stratum corneum,normal epidermal thickness,no inflammatory cell infiltration,and no morphological abnormalities.Hepatocytes were clearly structured,regularly arranged,and compact,with no obvious lipid vacuoles.In the psoriasis model group,skin lesions were covered with scales,with pinpoint bleeding upon scale shedding,and the skin appeared dark red and thickened.Epidermal thickening,parakeratosis,acanthosis,and inflammatory cell infiltration in the dermis were observed,with PASI scores significantly increased compared to the normal group(P＜0.01),while no significant changes were noted in hepatocytes.In the spleen deficiency and dampness retention syndrome group,body weight increased by more than 20%compared to the normal group,with mice exhibiting curled postures,sluggishness,and lethargy.Hepatocytes showed significant enlargement and swelling with numerous lipid vacuoles of varying sizes,while no abnormalities were observed in skin tissue.In the psoriasis with spleen deficiency and dampness retention model group,skin lesions were covered with scales,with pinpoint bleeding upon scale shedding,and the skin appeared dark red and thickened.Epidermal thickening,parakeratosis,acanthosis,and inflammatory cell infiltration in the dermis were observed.Hepatocytes showed significant enlargement and swelling with numerous lipid vacuoles of varying sizes.Body weight increased by more than 20%compared to the normal group,and PASI scores were significantly elevated(P＜0.01).Body weight in the psoriasis with spleen deficiency and dampness retention syndrome model group was significantly higher than that in the psoriasis model group(P＜0.01),and PASI scores were significantly higher than those in the spleen deficiency and dampness retention syndrome group(P＜0.01).Compared with the psoriasis with spleen deficiency and dampness retention syndrome model group,the high-dose GQHF group and the methotrexate group showed milder pathological changes in back skin lesions,with mild epidermal hyperplasia,slight hyperkeratosis,parakeratosis,and inflammatory cell infiltration,and no dermal capillary dilation.The GQHF groups exhibited significantly reduced lipid vacuoles and clearer hepatocyte structure.All treatment groups showed alleviated psoriasis severity with decreased PASI scores(P＜0.01),and body weight was reduced in the low-and high-dose GQHF groups(P＜0.05,P＜0.01).However,the methotrexate group still showed numerous vacuoles in hepatocyte structure,and the low-dose GQHF group exhibited no significant improvement in back skin lesions.(2)Compared with the normal group,the spleen deficiency and dampness retention syndrome group and the psoriasis with spleen deficiency and dampness retention syndrome model group showed significantly increased white adipose tissue index and serum levels of TC,LDL,AST,and ALT(P＜0.01),and decreased HDL levels(P＜0.01).The psoriasis model group and the psoriasis with spleen deficiency and dampness retention syndrome model group showed increased spleen index and serum levels of IL-6,IL-17A,TNF-α,and IL-1β(P＜0.01),and the spleen deficiency and dampness retention syndrome group showed increased serum levels of IL-6,IL-17A,and TNF-α(P＜0.01).Serum IL-4 levels were decreased in the psoriasis model group and the psoriasis with spleen deficiency and dampness retention syndrome model group(P＜0.01),while no significant changes were observed in spleen index,serum IL-1β levels in the spleen deficiency and dampness retention syndrome group,or white adipose tissue index and serum TC,LDL,AST,and ALT levels in the psoriasis model group(P＞0.05).Compared with the spleen deficiency and dampness retention syndrome group,the psoriasis with spleen deficiency and dampness retention syndrome model group showed increased spleen index and serum levels of IL-6,IL-17A,TNF-α,and IL-1β(P＜0.01),and decreased IL-4 levels(P＜0.01).Compared with the psoriasis model group,the psoriasis with spleen deficiency and dampness retention syndrome model group showed increased white adipose tissue index and serum levels of TC,LDL,AST and ALT,and decreased HDL levels(P＜0.05,P＜0.01).Compared with the psoriasis with spleen deficiency and dampness retention syndrome model group,the GQHF groups showed significantly decreased serum TC,LDL,AST,and ALT levels,white adipose tissue index,and serum IL-6,IL-17A,and TNF-α levels(P＜0.05,P＜0.01).Serum HDL levels in the GQHF groups and IL-4 levels in the high-dose GQHF group and methotrexate group were increased(P＜0.01).Spleen index in the high-dose GQHF group and IL-1β levels in the high-dose GQHF group and methotrexate group were significantly decreased(P＜0.05,P＜0.01).(3)Compared with the normal group,the psoriasis with spleen deficiency and dampness retention syndrome model group showed significantly increased mRNA expression levels of FABP5,CD36,and PPARγ in subcutaneous adipose tissue and significantly increased CD4+IL-17A+and CD4+T cell levels in spleen tissue(P＜0.01).The spleen deficiency and dampness retention syndrome group showed significantly increased mRNA expression levels of FABP5,CD36,and PPARγ in subcutaneous adipose tissue,and the psoriasis model group showed significantly increased CD4+IL-17A+and CD4+T cell levels in spleen tissue(P＜0.01).Compared with the spleen deficiency and dampness retention syndrome group,the psoriasis with spleen deficiency and dampness retention syndrome model group showed significantly increased CD4+IL-17A+and CD4+T cell levels in spleen tissue(P＜0.01).Compared with the psoriasis model group,the psoriasis with spleen deficiency and dampness retention syndrome model group showed significantly increased mRNA expression levels of FABP5,CD36,and PPARγ in subcutaneous adipose tissue(P＜0.01).Compared with the psoriasis with spleen deficiency and dampness retention syndrome model group,all treatment groups showed significantly decreased CD4+IL-17A+and CD4+T cell levels in spleen tissue and decreased mRNA expression levels of FABP5 and CD36 in subcutaneous adipose tissue(P＜0.05,P＜0.01).mRNA expression levels of PPARγ in subcutaneous adipose tissue were significantly decreased in the GQHF groups(P＜0.05,P＜0.01),while no significant change was observed in the methotrexate group(P＞0.05).(4)Compared with the normal group,the psoriasis with spleen deficiency and dampness retention syndrome model group showed significantly increased protein expression levels of FABP5 and CD36 in skin tissue(P＜0.01),and decreased p-PPARγ/PPARγ protein expression(P＜0.01).Compared with the psoriasis with spleen deficiency and dampness retention syndrome model group,the GQHF groups showed significantly decreased protein expression levels of FABP5 and CD36 in skin tissue(P＜0.05,P＜0.01),and significantly increased p-PPARγ/PPARγ protein expression(P＜0.01).The methotrexate group showed decreasing trends in FABP5 and CD36 protein expression in skin tissue compared with the model group,but the differences were not statistically significant(P＞0.05).Conclusion A mouse model of psoriasis with spleen deficiency and dampness retention syndrome was successfully established in this study,characterized by both psoriatic skin lesions and lipid metabolism disorders.Guben Qushi Huayu Formula may exert its therapeutic effects on psoriasis with spleen deficiency and dampness retention syndrome by modulating the FABP5/PPARγ pathway to improve immune imbalance and lipid metabolism disorders in these mice.