Therapeutic effects of liver soothing pingchuan formula decoction on experimental asthma in BALB/c mice via regulation of nerve growth factor-tyrosine kinase A pathway.

The present study was designed to investigate the effects of liver soothing pingchuan formula decoction (LSPF) on experimental asthma in BALB/c mice and explore its potential molecular mechanisms. An animal model of asthma was established in BALB/c mice through sensitization and activation with intraperitoneal injection of 10% ovalbumin (OVA)/Al(OH)3 solution in addition to inhalation of a 5% OVA solution. LSPF (300 and 600 mg/kg/day) was initially administered orally prior to activation. Following this, bronchoalveolar lavage fluid (BALF) and lung tissues were collected for histopathalogical examination. Levels of inflammatory cells and cytokines were determined in the BALF, and levels of nerve growth factor (NGF) and tyrosine kinase A (TrkA) in the lung tissues were determined. The results of the present study indicated that increased inflammatory reactions were observed following OVA sensitization (P<0.05), and the expression levels of NGF (P<0.05) and TrkA (P<0.05) were significantly increased, compared with normal mice. Notably, compared with the asthma model group, immunohistochemical results revealed that LSPF treatment suppressed OVA induced inflammatory reactions (P<0.05) and NGF (P<0.05) and TrkA expression levels (P<0.05). In addition, the NGF (P<0.05) and TrkA (P<0.05) were revealed to be downregulated with LSPF treatment from the results of the ELISA and western blotting assay. Overall, the results of the present study demonstrated that LSPF exhibits therapeutic effects on experimental asthma in mice, via downregulation of the NGF-TrkA pathway.

[Effects of Chinese herbal medicine Pingchuan Formula on airway inflammation, interferon-γ and interleukin-4 in mice with asthma].

OBJECTIVE: To observe the changes of interferon-γ (IFN-γ) and interleukin-4 (IL-4), factors related to T helper 1/T helper 2 (Th1/Th2), in airway inflammation in an asthmatic model of mice and the effects of Pingchuan Formula (PCF), a compound traditional Chinese herbal medicine. METHODS: Eighty BALB/c mice were randomly divided into normal group, model group, dexamethasone group and PCF group, with 20 mice in each group. For inducing asthma, the BALB/c mice were sensitized by intraperitoneal injection of mixed ovalbumin, and then activated by inhaling ovalbumin. After 2 weeks of sensitizing, asthmatic mice were intragastrically administered with the drugs once a day for four weeks. Bronchoalveolar lavage fluid (BALF) and lung tissue were collected respectively after 7-day activation or 2 weeks after activation. The general histological changes were observed by hematoxylin and eosin staining and collagen staining, meanwhile the levels of IFN-γ and IL-4 in BALF were detected by enzyme-linked immunosorbent assay. RESULTS: After 7 d of activation, compared with the normal group, significant decrease in IFN-γ and increase in IL-4 were detected in the model group; compared with the model group, IL-4 level of the two treated groups was decreased and the IFN-γ/IL-4 ratio was increased significantly; no significant difference was found between the two treated groups. Two weeks after activation, compared with the normal group, IFN-γ was decreased, IL-4 was increased, and the IFN-γ/IL-4 ratio was decreased in the model group; compared with the model group, IL-4 level in the dexamethasone group was significantly decreased and IFN-γ/IL-4 ratio was significantly elevated, while the level of IL-4 in the PCF group was significantly decreased, the level of IFN-γ was increased simultaneously, and the IFN-γ/IL-4 ratio was significantly elevated. There was no significant difference between the two treated groups in IFN-γ and IL-4 levels, nor in the IFN-γ/IL-4 ratio. The area of collagen fiber in airway wall epithelium in the model group was smaller than that in the normal group, and those in the treated groups were lower than that in the model group; there was no significant difference between the two treated groups. CONCLUSION: PCF has regulating function in correcting the imbalance of Th1/Th2 so as to improve airway inflammation. The therapeutic effects of PCF are basically similar to dexamethasone.