Psoriasis is an incurable, chronic and auto-immune skin disorder with a global prevalence rate of approximately 2-3%. The study investigated the antipsoriasis activities of Deprungsith formulation and its bioactive components and their potential for inhibitory activities on human cytochrome P450 (CYP450). HaCaT and peripheral blood mononuclear cells (PBMCs) from healthy volunteers (n = 9) and psoriasis patients (n = 10) were exposed to Deprungsith formulation (Thai traditional medicine for psoriasis consisting of 16 plants), ethyl p-methoxycinnamate (EPMC), ligustilide and cyclosporin for 24 and 48 h. The antiproliferative, cell apoptosis and cell cycle arrest activities were evaluated using MTT assay and flow cytometry, respectively. The pro-inflammatory cytokine mRNA expression levels were measured using real-time polymerase chain reaction (RT-PCR). The CYP450 inhibitory effect was investigated using a bioluminescent-based CYP450 assay. Deprungsith formulation and the bioactive compounds inhibited HaCaT cells and PBMCs with weak to moderate potencies. EPMC and ligustilide combination produced an additive effect. Most substances arrested cell transition at sub-G1 and S phases, leading to early and late apoptosis induction. With prolonged exposure (48 h), all test substances decreased PBMCs necrosis. The mRNA expression of all pro-inflammatory cytokines was downregulated. Deprungsith formulation, EPMC, ligustilide and ferulic acid inhibited CYP1A2, CYP2C9, CYP2D6 and CYP3A4 activities with weak to moderate potencies. Deprungsith formulation and bioactive components induced cell apoptosis by inhibiting cell transition at specific cell cycle phases, which was correlated with the mRNA downregulation of interleukin (IL-6, IL-12p19, IL-23) and tumor necrosis factor (TNF-α). There is a low risk of potential adverse drug reactions and toxicity due to CYP450 interaction when Deprungsith formulation is concurrently administered with modern medicines.
Keywords: antipsoriasis; cytochrome P450 interaction; deprungsith formulation; ethyl p-methoxycinnamate; ligustilide.