Repair effect of Qinbai Qingfei concentrated pellets to AEC-Ⅱ of rats infected by Mycoplasmal pneumonia / 中国中药杂志

ABSTRACT

To discuss the repair mechanism of Qinbai Qingfei concentrated pellets to AEC-Ⅱ of rats infected by mycoplasma through the observation of the changes and distribution of TGF-β and SP-A in lungs, totally 60 Wistar rats that weighing 80-100 g were collected, with male and female in half. The rats were divided into six groups randomly, with 10 rats each group, namely blank group, model group, positive group and Qinbai Qingfei concentrated pellets high, middle and low dose groups. Rats were infected through nasal intubation drip of MP. After 10 days of administration, serum and bronchoalveolar lavage fluid (BALF) were collected to detect the concentration of surface activity related protein A (SP-A) by ELISA, left pulmonary tissues of rats were collected to observe the expression and distribution of transforming growth factor-beta (TGF-β) and SP-A by immunohistochemistry, and right pulmonary tissues were taken to detect TGF-β and SP-A mRNA expression level by real-time quantitative PCR (RT-PCR). Qinbai Qingfei concentrated pellets can reduce the expression of TGF-β and increase the expression of SP-A in the lung tissues of rats infected by mycoplasma. Specifically, TGF-β was mainly distributed among the lung interstitium, while SPAs were mainly distributed in AEC-II and parts of alveolar macrophage. The level of SP-A was reduced in serum and increased in BALF in rats in Qinbai Qingfei concentrated pellets groups. It was proved that Qinbai Qingfei concentrated pellets can restore the normal morphology and function of the lung by reducing the content of TGF-β to inhibit epithelial-mesenchymal transition (EMT) of alveolar type II epithelial cells and increasing the expression of SP-A. Qinbai Qingfei concentrated pellets have the repairing ability to capillary vessel damage caused by MP in lung tissues of rats.