Background: PentaHerbs formula (PHF) containing Cortex Moutan, root bark of Paeonia suffruticosa Andr. (Ranunculaceae), Cortex Phellodendri, bark of Phellodendron chinensis Schneid. (Rutaceae), Flos Lonicerae, flower of Lonicera japonica Thunb. (Capri-foliaceae), Herba Menthae, aerial part of Mentha haplocalyx Briq. (Labiatae) and Rhizoma Atractylodis, rhizome of Atractylodes lancea (Thunb.) DC. (Compositae) at the ratio of 2:2:2:1:2 was useful in the management of eczema.
Aim of the study: Since the mechanism of action of PHF is not known, we aimed to investigate the actions of PHF on mast cell activation.
Materials and methods: Effects of aqueous extracts of PHF and individual component herb on mediator release from rat peritoneal mast cells (RPMCs) and cytokine production from HMC-1 were investigated.
Results: PHF, Cortex Moutan and Herba Menthae significantly attenuated histamine release and prostaglandin D(2) synthesis from RPMC activated by anti-IgE and compound 48/80 (p<0.05). While Flos Lonicerae and Rhizoma Atractylodis suppressed only mediator release from compound 48/80 activated RPMC, Cortex Phellodendri potentiated only anti-IgE induced mediator release (p<0.05). However, with the exception of Cortex Moutan, PHF and the other four component herbs failed to affect cytokine production in HMC-1.
Conclusions: Although individual herbs demonstrated different modulating effects on mast cells, inhibition of inflammatory mediator release from mast cells would contribute to the therapeutic efficacy of PHF.