The effect of Qingfei Chengqi decoction on lung tissue cell apoptosis in rats with severe intraperitoneal infection / 中国中西医结合急救杂志

ABSTRACT

Objective To observe the effects of Qingfei Chengqi decoction on lung tissue cell apoptosis and its associated protein,tumor necrosis factor-α(TNF-α),interleukin-6(IL-6)of lung tissues in rats with severe intra-peritoneal infection(SII). Methods Thirty male Wistar rats were randomly divided into three groupssham operation group,model group and traditional Chinese medicine(TCM)group(each n=10). Simulating clinical pathophysiological process of digestive tract perforation,the rat model of SII was reproduced by injecting E. coli intraperitoneally. The TCM group was treated by gavage with Qingfei Chengqi decoction one day in advance of the study,3 times per day,once 2 mL. The same amount of nutrient broth which contained 10%barium sulfate(BaSO4) to replace the bacteria solution was injected into the sham operation group. Six hours after model establishment,all rats were killed and lung tissues were harvested for pathohistological evaluation and for the determination of apoptosis rate with TdT-mediated dUTP nick-end labeling(TUNEL)method,of Bax,Bcl-2 protein expression with Western Blot method,and of the level of TNF-α,IL-6 with enzyme-linked immunosorbent assay(ELISA)method,and the pathological changes of lung tissues were observed under the light and electron microscopes. Results Compared with sham operation group,the apoptosis rate〔(12.7±5.4)%vs. 0〕,the expression of Bax protein〔absorbance(A)value8 416.89±875.16 vs. 6 654.09±1 130.18〕,the level of TNF-α(ng/L3 132.56±457.96 vs. 1 948.55±269.32), the level of IL-6(ng/L75.14±1.63 vs. 31.17±0.81)of lung tissues were significantly increased(all P<0.05), meanwhile Bcl-2 protein expression decreased observably(A value7 490.59±200.34 vs. 12 289.02±535.93,P<0.05)in model group induced by SII. After treatment with TCM,apoptosis rate〔(7.9±0.3)%〕,the expression of Bax protein(A value7 619.50±999.30),the level of TNF-α(ng/L3 114.34±454.32)and IL-6(ng/L52.46±0.96) of lung tissues were decreased and Bcl-2 protein expression(A value11 155.07±1 018.87)increased(all P<0.05) compared with model group. General observationthe color of lung tissues was uniform in sham operation group;the lung tissues of model group swelled obviously,and parts of lung tissues had patches of ecchymosis and hemorrhage. The light microscope showedthe pulmonary vessels,the alveolar interstitium,alveolar epithelium and lobular interstitium of sham operation group were all normal,while in the model group,the pulmonary interstitium was edematous and hemorrhagic,and in the alveolar cavities there was infiltration of inflammatory cells. Under the electron microscope, the lung tissue type Ⅱ alveolar epithelial cells of model group were increased,and they had morphological changes in various degrees,such as cell shrinkage and change becoming round,and cell nucleus presenting irregular in shape. After treatment with TCM,the above pathological changes were all alleviated compared with those in the model group. Conclusions Qingfei Chengqi decoction can ameliorate the SII leading to acute lung injury,and reduce the cell apoptosis rate of lung tissues in SII rats. Its mechanism may be related to the intervention of above TCM which can lower the levels of inflammatory media and elevate the protein expression of Bcl-2.