[Exploring the treatment of sepsis-associated acute lung injury with Liangge Powder via ERK1/2 and PI3K/AKT pathways: based on network pharmacology and whole animal experimentation]

Objective: To investigate the therapeutic effect and mechanism of Liangge Powder against sepsis-induced acute lung injury (ALI) . Methods: From April to December 2021, the key components of Liangge Powder and its targets against sepsis-induced ALI were analyzed by network pharmacology, and to enrich for relevant signaling pathways. A total of 90 male Sprague-Dawley rats were randomly assigned to sham-operated group, sepsis-induced ALI model group (model group), Liangge Powder low, medium and high dose group, ten rats in the sham-operated group and 20 rats in each of the remaining four groups. Sepsis-induced ALI model was established by cecal ligation and puncture. Sham-operated group: gavage with 2 ml saline and no surgical treatment. Model group: surgery was performed and 2 ml saline was gavaged. Liangge Powder low, medium and high dose groups: surgery and gavage of Liangge Powder 3.9, 7.8 and 15.6 g/kg, respectively. To measure the wet/dry mass ratio of rats lung tissue and evaluate the permeability of alveolar capillary barrier. Lung tissue were stained with hematoxylin and eosin for histomorphological analysis. The levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL) -6 and IL-1β in bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay. The relative protein expression levels of p-phosphatidylinositol 3-kinase (PI3K), p-protein kinase B (AKT), and p-ertracellular regulated protein kinases (ERK) were detected via Western blot analysis. Results: Network pharmacology analysis indicated that 177 active compounds of Liangge Powder were selected. A total of 88 potential targets of Liangge Powder on sepsis-induced ALI were identified. 354 GO terms of Liangge Powder on sepsis-induced ALI and 108 pathways were identified using GO and KEGG analysis. PI3K/AKT signaling pathway was recognized to play an important role for Liangge Powder against sepsis-induced ALI. Compared with the sham-operated group, the lung tissue wet/dry weight ratio of rats in the model group (6.35±0.95) was increased (P<0.001). HE staining showed the destruction of normal structure of lung tissue. The levels of IL-6 [ (392.36±66.83) pg/ml], IL-1β [ (137.11±26.83) pg/ml] and TNF-α [ (238.34±59.36) pg/ml] were increased in the BALF (P<0.001, =0.001, <0.001), and the expression levels of p-PI3K, p-AKT and p-ERK1/2 proteins (1.04±0.15, 0.51±0.04, 2.31±0.41) were increased in lung tissue (P=0.002, 0.003, 0.005). The lung histopathological changes were reduced in each dose group of Liangge Powder compared with the model group. Compared with the model group, the wet/dry weight ratio of lung tissue (4.29±1.26) was reduced in the Liangge Powder medium dose group (P=0.019). TNF-α level [ (147.85±39.05) pg/ml] was reduced (P=0.022), and the relative protein expression levels of p-PI3K (0.37±0.18) and p-ERK1/2 (1.36±0.07) were reduced (P=0.008, 0.017). The wet/dry weight ratio of lung tissue (4.16±0.66) was reduced in the high-dose group (P=0.003). Levels of IL-6, IL-1β and TNF-α[ (187.98±53.28) pg/ml, (92.45±25.39) pg/ml, (129.77±55.94) pg/ml] were reduced (P=0.001, 0.027, 0.018), and relative protein expression levels of p-PI3K, p-AKT and p-ERK1/2 (0.65±0.05, 0.31±0.08, 1.30±0.12) were reduced (P=0.013, 0.018, 0.015) . Conclusion: Liangge Powder has therapeutic effects in rats with sepsis-induced ALI, and the mechanism may be related to the inhibition of ERK1/2 and PI3K/AKT pathway activation in lung tissue.