Apoptosis Regulation by Buzhong Yiqitang via PERK/eIF2α/ATF4/CHOP Pathway to Enhance Pulmonary Surfactant-associated Protein C Expression and Ameliorate Lung Injury in CIH Mice
10.13422/j.cnki.syfjx.20242242
- VernacularTitle:补中益气汤通过PERK/eIF2α/ATF4/CHOP通路调控凋亡改善CIH小鼠肺表面活性蛋白C的表达及肺损伤
- Author:
Luyao ZHANG
1
;
Yangjing WANG
1
;
Bingbing LIU
1
;
Jieru LI
1
Author Information
1. Hebei University of Chinese Medicine， Shijiazhuang 050200， China
- Publication Type:Journal Article
- Keywords:
Buzhong Yiqitang;
intermittent hypoxia;
endoplasmic reticulum stress;
pulmonary surfactant-associated protein C
- From:
Chinese Journal of Experimental Traditional Medical Formulae
2025;31(15):19-27
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the effects of Buzhong Yiqitang on the abnormal expression of pulmonary surfactant-associated protein C （SFTPC） and lung injury induced by chronic intermittent hypoxia （CIH） and the mechanism of action. MethodsForty healthy adult male SPF-grade C57BL/6 mice were randomly allocated into five experimental groups： a normoxia group， a CIH group， and low-， medium-， and high-dose Buzhong Yiqitang groups， with eight mice in each group. During the modeling， mice in the normoxia group were housed under standard oxygen concentrations， while the CIH and all Buzhong Yiqitang groups were placed in a hypoxic chamber for 8 h daily over 35 d. Prior to each chamber session， mice in the low-， medium-， and high-dose Buzhong Yiqitang groups were administered decoctions by gavage at corresponding doses （8.1， 16.2， 32.4 g·kg-1·d-1 of crude drug， respectively）， while those in normoxia and CIH groups received an equivalent volume of saline by gavage. The general conditions of the mice were recorded before and after the experiment. Pulmonary function was assessed using a non-invasive detection system. Serum SFTPC levels were measured using enzyme-linked immunosorbent assay （ELISA）. Histopathological changes in lung tissue were evaluated using hematoxylin-eosin （HE） staining. Apoptosis in lung tissue was detected using terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL）. Protein expression of SFTPC， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， protein kinase R-like endoplasmic reticulum kinase （PERK）， phosphorylated PERK （p-PERK）， eukaryotic initiation factor 2α （eIF2α）， phosphorylated eIF2α （p-eIF2α）， activating transcript factor 4 （ATF4）， and CCAAT/enhancer-binding protein homologous protein （CHOP） in lung tissue was analyzed by Western blot. Immunofluorescence staining was employed to assess the expression of SFTPC and CHOP proteins in lung tissue. ResultsCompared to those in the normoxia group， mice in the CIH group showed significantly impaired pulmonary function and increased histopathological lung injury scores （P<0.05， P<0.01）. Serum SFTPC levels increased， while SFTPC expression in lung tissue was reduced （P<0.05， P<0.01）. The rate of apoptotic cells in lung tissue increased， and the expression of endoplasmic reticulum stress markers p-PERK， p-eIF2α， ATF4， and CHOP was upregulated （P<0.05， P<0.01）. Compared with the CIH group， Buzhong Yiqitang intervention improved pulmonary function indicators and decreased the histopathological lung injury scores （P<0.05， P<0.01）. Serum SFTPC levels were decreased， and lung tissue SFTPC expression was recovered （P<0.05， P<0.01）. The apoptotic rate of lung tissue cells was significantly reduced， with downregulation of pro-apoptotic Bax and upregulation of anti-apoptotic Bcl-2 expression （P<0.05， P<0.01）. Activation and expression of p-PERK， p-eIF2α， ATF4， and CHOP were also decreased （P<0.05， P<0.01）. ConclusionBuzhong Yiqitang can alleviate lung injury and improve pulmonary function by reducing lung cell apoptosis and enhancing alveolar surfactant secretion， which may be related to the modulation of the PERK/eIF2α/ATF4/CHOP signaling pathway.
