Study On The Mechanism Of Jianpi Jiedu Decoction Treatment Of Psoriasis With Spleen Deficiency And Dampness Syndrome Based On AQP3

Objective: To study the effect of Jianpi Jiedu decoction(JPJD)on the expression of Aquaporins 3(AQP3)and serum IL-22,IL-17 A in the psoriatic-like skin skin inflammation rat model with spleen deficiency and dampness syndrome,and to conduct a preliminary study on the partial mechanism of JPJD in repairing skin barrier function.Methods: According to the random number table,72 male SD rats were randomly divided into 6 groups: negative control group,model group,positive control group,JPJD(low dose)group,JPJD(medium dose)group and JPJD(high dose)group,12 rats in each group.The negative control group was treated with a twice daily application of equal amount of Vaseline and was subjected to the saline gavage treatment.The remaining groups received a twice daily application of imiquimod(IMQ)cream and gavaged with rhubarb aqueous decoction to establish IMQ-induced psoriasis rat model with spleen deficiency and dampness syndrome.The experiment was conducted for 10 days.After the establishment of IMQ-induced psoriasis rat model,the positive control group was given Methotrexate tablets 0.97 mg/kg via gavage,and the low,medium and high dose groups were given JPJD 2.32 g/kg,4.64 g/kg,and 9.26 g/kg via gavage daily for 14 days.We described the characterization of spleen deficiency and dampness in psoriasis rats,the histological changes of skin tissues by H&E staining,and the expression of AQP3 protein in skin tissues by Western-Blot.The concentrations of serum IL-22,IL-17 A were detected by ELISA.Results: We observed significant improvement in the symptoms of IMQ-induced psoriasis rat model with spleen deficiency and dampness syndrome at low,medium,and high doses of JPJD.The skin structure of the negative control group was basically normal.However,rats in the model group showed hyperplastic hypertrophy of the epidermis,significant keratosis imperfecta with hyperkeratosis prolonged epidermal protrusions,partial epidermal intercellular edema,more neutrophil infiltration in the epidermis and the stratum corneum,dilated blood vessels in the superficial dermis,scattered or focal infiltration of chronic inflammatory cells.The rest of the experimental group was significantly improved compared with the model group by giving different doses of JPJD.Western-blot results showed that AQP3 protein was significantly decreased in the skin tissues of rats in the model group compared with the negative control group(all P < 0.05).Compared with the model group,the AQP3 protein expression was increased in the positive control group and the low,medium,and high dose groups of JPJD(all P <0.05).Compared with the positive control group,the AQP3 protein expression levels of rats in the low,medium,and high dose groups of JPJD were not significantly different(p>0.05).ELISA results showed that the concentrations of serum IL-22 of was significantly improved in the model group compared with the negative control group.Compared with the model group,the concentrations of serum IL-22 was decrease in the positive control group,and themedium,high dose groups of JPJD(all P < 0.05).Compared with the negative control group,the serum IL-17 A expression level of rats in the model group was increased,and compared with the model group,the low,middle and high dose groups of JPJD significantly decreased(all P < 0.05).Conclusion: Our results suggest that JPJD improve the expression level of AQP3 protein in the skin of rats with psoriasis due to spleen deficiency and dampness and restore the skin barrier function by promoting the main function of the spleen in transporting water and fluid to relieve dryness and itching.