To elucidate the effect and possible mechanism of Zhichuan Capsule (ZCC), a Chinese herbal preparation for reinforcing Kidney and invigorating Spleen, on airway remodeling when it was used in treating asthma.
Fifty SD rats were randomly divided into five groups: the normal control group, the model group, the high-dosage ZCC group, the low-dosage ZCC group and the Becotide (Beclomethasone Dipropionate) group, 10 rats in each group. The chronic asthma model was established by repeated inhalation of ovalbumin. The changes of collagen and fibronectin (Fn) content in airway wall, inner and outer diameter as well as area of respiratory tract cavity in lung slices were measured by computerized image analysis system.
The wall contents of collagen and Fn in airway were higher (P < 0.05 and P < 0.01), while the ratio of inner diameter/outer diameter (ID/OD) and ratio of area of airway cavity/total area of airway (CA/TA) were significantly lower (P < 0.01) in the model animals than those in the normal controls. As compared with the model group, collagen and Fn contents were lower, ID/OD and CA/TA ratio were significantly higher in high-dosage ZCC group, close to normal range. In the low-dosage ZCC group, although collagen content, ID/OD and CA/TA were not different to those in the model group, but the content of Fn was significantly lower (P < 0.01).
ZCC could inhibit the remodeling of airway in chronic asthma by way of reducing the precipitation of collagen and Fn, thus help the prevention and treatment of chronic bronchial asthma.