Anti-asthmatic actions of ayanin and biochanin A
| Autor: | Hsin-Yi Shen, 沈欣儀 |
|---|---|
| Rok vydání: | 2008 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 96 Ayanin (quercetin-3,4′,7-O-trimethylether) is a methyl derivative of quercetin, it have been reported to inhibit phosphodiesterase (PDE) activities. The PDE4H/PDE4L ratio of ayanin was reported to be more than 19. Biochanin A, known as one of phytoestrogens, is the main ingredient of the red clover (Trifolium pretense L.), and has been reported to inhibit PDE activities. The PDE4H/PDE4L ratio of biochanin A was reported to be more than 35. Therefore we are interested in their mechanisms of anti-asthmatic effect. In the OVA-induced allergic asthma model of BALB/c mice, ayanin (30~100 μmol/kg, p.o.) revealed it dose-dependently and significantly attenuated the enhance pause (Penh) value induced by MCh (25~50 mg/ml). Ayanin (30~100 μmol/kg, p.o.) also significantly reduced total inflammatory cells, macrophages, lymphocytes, neutrophils and eosinophils. Ayanin (10~100 μmol/kg, p.o.) significantly attenuated the release of IL-2、IL-4, IL-5 and TNF-α, with the exception that ayanin (10 μmol/kg) did not attenuate the release of TNF-α. Ayanin at 100 μmol/kg significantly increased the release of IFN-γ. Ayanin (30~100 μmol/kg, p.o.) also significantly reduced total and OVA-specific IgE levels in the BALF and the serum, but increased IgG2a level in the serum. In the present results, ayanin (300 μmol/kg, s.c.) did not significantly shorten duration of anesthesia induced by xylazine (10 mg/kg)/ketamine (70 mg/kg). Biochanin A (100 μmol/ml, p.o.) significantly attenuated the enhanced pause (Penh) value induced by MCh (25~50 mg/ml), and also significantly reduced total inflammatory cells, neutrophils and eosinophils. Biochanin A (30~100 μmol/kg p.o.) significantly attenuated the release of IL-2, IL-4, IL-5, and TNF-α, with the exceptions that it at 30 μmol/kg did not significantly inhibit the release of IL-2 and TNF-α. Biochanin A 100, but not 30 μmol/kg, p.o., significantly reduced total and OVA-specific IgE levels in the BALF and the serum, but increased IgG2a levels in the serum. In the present results, Biochanin A (300 μmol/kg s.c.) did not significantly shorten the duration of anesthesia induced by xylazine (10 mg/kg)/ketamine (70 mg/kg). Ayanin (100 μM) and biochanin A (100 μM) significantly relaxed the baseline tension of isolated sensitized guinea pig trachealis, and also significantly suppressed cumulative OVA (10~100 μg/ml)–induced contractions. In conclusion, ayanin and biochanin A possessed anti-inflammatory effects and prevented airway hyperresponsiveness. Furthermore, they may prevent from degranulation of mast cells. Therefore, they have the potential in treating asthma. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|