Effect of Phlomis umbrosa root on mast cell-dependent immediate-type allergic reactions by anal therapy

The effect of aqueous extract of Phlomis umbrosa Turcz. (Labiatae) root (PUAE) on mast cell-dependent immediate-type allergic reaction by anal therapy was investigated. PUAE (0.01 to 1 g/kg) dose-dependently inhibited systemic anaphylaxis induced by compound 48/80 in mice. When PUAE was pretreated at the same concentrations with systemic anaphylaxis, the plasma histamine levels were reduced in a dose-dependent manner. PUAE (0.1 and 1 g/kg) also significantly inhibited local anaphylaxis activated by anti-DNP IgE. PUAE (0.001 to 1 mg/mL) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cyclic AMP (cAMP) in human mast cells (HMC-1 cells) when PUAE (1 mg/mL) was added, transiently and significantly increased compared with that of basal cells. In addition, PUAE (0.1 and 1 mg/mL) inhibited the secretion of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6 in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated HMC-1 cells. These results provide evidence that anal therapy of PUAE may be beneficial in the treatment of allergic diseases.