Total Glucosides of Paeony Regulate Immune Imbalance Mediated by Dermal Mesenchymal Stem Cells in Psoriasis Mice.

objectiveTo investigate the therapeutic effects of total glucosides of paeony (TGP) on psoriasis based on the immunomodulatory effect of dermal mesenchymal stem cells (DMSCs).

methodsA total of 30 male BALB/c mice were divided into 6 groups (n=5 in each) by a random number table method, including control, psoriasis model (model, 5% imiquimod cream 42 mg/d), low-, medium- and high-dose TGP (50, 100, and 200 mg/kg, L, M-, and H-TGP, respectively), and positive control group (2.5 mg/kg acitretin). After 14 days of continuous administration, the skin's histopathological changes, apoptosis, secretion of inflammatory cytokines, and proportion of regulatory T cells (Treg) and T helper cell 17 (Th17) were evaluated using hematoxylin-eosin (HE) staining, TdT-mediated dUTP nick end labeling staining, enzyme-linked immunosorbent assay, and flow cytometry, respectively. DMSCs were further isolated from the skin tissues of normal and psoriatic mice, and the cell morphology, phenotype, and cycle were observed. Furthermore, TGP was used to treat psoriatic DMSCs to analyze the effects on the DMSCs immune regulation.

resultsTGP alleviated skin pathological injury, reduced epidermis layer thickness, inhibited apoptosis, and regulated the secretion of inflammatory cytokines and the proportion of Treg and Th17 in the skin tissues of psoriatic mice (P<0.05 or P<0.01). There was no significant difference in cell morphology and phenotype between control and psoriatic DMSCs (P>0.05), however, more psoriatic DMSCs remained in G

conclusionTGP may exert a good therapeutic effect on psoriasis by regulating the immune imbalance of DMSCs.