Qu Feng Xuan Bi Formula attenuates anaphylactic rhinitis–asthma symptoms via reducing EOS count and regulating T cell function in rat ARA models

Abstract

Ethnopharmacological relevanceAqueous extract of Qu Feng Xuan Bi Formula (QFXBF, a Chinese herb formula) which composed of Radix Glycyrrhizae, Radix Glycyrrhizae Preparata, Paeonia sterniana Fletcher in Journ, Pheretima, Allium macrostemon Bunge, Astragalus membranaceus (Fisch) Bunge and Divaricate Saposhnikovia Root has been used in treatment of allergic rhinitis and asthma (ARA) as an approved hospital prescription for many years in Jiangsu Province Hospital of Traditional Chinese Medicine, China. The present study was designed to investigate the effect of the aqueous extract of QFXBF in the gene expression of Toll-like receptor 9 (TLR9) and the manners of immune modulation of T cell-associated interleukin (IL-4 and IL-13) in rat ARA models. Materials and methodsFifty SD male rats were divided into five groups: not treated group, OVA only group (treated only with OVA), dexamethasone (DXM) group, low dose QFXBF group and high dose QFXBF group randomly (n=10 per group). Rat allergic rhinitis and asthma model was developed by ovalbumin (OVA) sensitization and nose infusion. Pathological changes of nasal tissue and lungs were examined by H&E staining. Gene expressions of TLR9, Stat 3, Jak-1 and C-Jun in nasal tissue were assayed by real-time polymerase chain reaction (RT-PCR). The serum and broncho-alveolar lavage fluid (BALF) levels of T cell-associated interleukin (IL-4 and IL-13) were determined by enzyme-linked immunosorbent assay (ELISA). ResultThe ARA model was successfully established. Marked EOS count was observed in BALF from ARA models. The aqueous extract of QFXBF could reduce EOS levels and increase TLR9 expression, but did not affect the gene expression of Stat-3 and Jak-1 and C-Jun. The reduction of IL-13 concentration in serum from high dose QFXBF group was observed in BALF, albeit not significantly. Despite the not treated group, serum levels of IL-4 had significantly increased in other four groups (P<0.001, n=4–6) but made higher in low dose QFXBF group and DXM group (P<0.05, n=4–6). ConclusionThis study originally provides the evidence that the aqueous extract of Qu Feng Xuan Bi Formula alone is effective in the treatment of anaphylactic rhinitis–asthma symptoms. The extract of Qu Feng Xuan Bi Formula was effective to reduce the eosophil recruitment to the lung. In addition it increased the IL-4 concentration in the BALF and expression of TLR9 in the nasal tissue. No alteration was observed in the IL-13 concentration in the BALF and expression of STAT-3, JAK-1 and C-Jun in nasal tissue. The results thereby scientifically provided mechanism of these aqueous extract of QFXBF in improvement of ARA and supported its clinical use.