Anti-asthmatic effect of Ping-Chuan Formula in asthmatic mice, and its molecular mechanism of action

Purpose: To investigate the anti-asthmatic effect of Ping-Chuan Formula (PCF) in a mouse model, and the associated molecular mechanisms. Methods: Asthma mice were induced using ovalbumin (OVA), and PCF (600 mg/kg) was administered to the mice for 4 weeks. Sections of lung tissues were examined microscopically. The expressions of interleukins (ILs), interferon (IFN)-gamma, transforming growth factor (TGF)-beta were assayed, while lung tissue expressions of Toll like receptor (TLR)-4, GATA binding protein (GATA)-3, Ox40 ligand (OX40L), indoleamine 2,3-dioxygenase (IDO), and forkhead box P3 (Foxp3) determined. The T box expressed in T cells (T-bet) was evaluated using western blotting. The expressions of MHC II and co-stimulators (CD 11c, CD 80 and CD 86) of dendritic cells (DCs) were determined by flow cytometry. Results: PCF decreased inflammation in lung, and also down-regulated IL-4,-6,-17 and TGF-beta (p < 0.01), whereas IL-10 and IFN-gamma expressions were up-regulated (p < 0.01). Moreover, PCF decreased the expressions of TLR-4, GATA-3 and OX40L in lung tissue, and promoted Foxp3, IDO and T-bet. Besides, PCF decreased the levels of MHC II and co-stimulators (CD 80 and CD 86) on the surface of DCs. Conclusion: PCF exerts anti-asthmatic effect in mice via inhibition of inflammation, and modulation of MHC II and co-stimulators on the surface of DCs. These findings suggest that PCF is a promising candidate drug for treating asthma in humans.