Exploring the material basis and mechanism of Astilbe chinensis for acute lung injury via integrated network pharmacology and experimental validation.

Ethnopharmacological Relevance: Acute lung injury (ALI), a critical complication of severe pneumonia, lacks targeted therapies. Astilbe chinensis (Maxim.) Franch. & Sav. possesses documented anti-inflammatory and respiratory-protective properties, yet its efficacy against ALI, bioactive constituents, and mechanisms remain unexplored.

Aim Of The Study: This study sought to evaluate the therapeutic efficacy and elucidate the mechanisms of action of Astilbe chinensis in the treatment of ALI through the application of network pharmacology and experimental methodologies.

Materials And Methods: UHPLC-MS was used to analyze plasma components absorbed after Astilbe chinensis administration in rats. Inflammation-related targets and pathway enrichment analyses were conducted via network pharmacology technique. Pulmonary function was assessed using forced lung function measurements in a LPS-induced ALI mouse model. ELISA quantified inflammatory mediators, including pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IFN-γ), chemokines (CCL5, CXCL2), and the anti-inflammatory cytokine IL-10 in mouse lung tissue. Flow cytometry evaluated macrophage polarization, and HE staining examined histopathological changes. qRT-PCR determined the mRNA expression levels of genes like CCR1, IKBKB, CXCL8, STAT3, CXCR4, AKT1, CCL3, CCL5, iNOS, Arg1, YM1 and CCR5, while simple western analysis evaluated the protein expression of t-AKT, p-AKT, t-STAT3, p-STAT3, CCR1 and CCR5 in mouse lung tissues affected by Astilbe chinensis.

Results: In this study, 20 blood-borne components of Astilbe chinensis were identified, predicted to interact with 369 potential molecular targets, with 331 related to ALI treatment. GO and KEGG pathway analyses showed that 36 targets participate in inflammatory processes, mainly via chemokine signaling pathways. Key targets identified include CCR1, IKBKB, CXCL8, STAT3, CXCR4, AKT1, and CCR5. The principal active constituents of Astilbe chinensis with potential efficacy against ALI were identified as cyclo(phenylalanyl-prolyl), 5-(6-hydroxy-6-methyloctyl)- -2,5-dihydrofuran-2-one, nicotinamide, 3-phenyllactic acid, and phloretin. In vivo studies demonstrated that Astilbe chinensis administration significantly increased M2 macrophage populations in lung tissue while improving forced pulmonary function parameters. Furthermore Astilbe chinensis reduces the levels of inflammatory factors TNF-α, IL-6, IFN-γ, CCL5 (the ligand for CCR5 and CCR1), and the neutrophil chemokine CXCL2 in the lung tissues of ALI mice, while significantly increasing the content of the anti-inflammatory cytokine IL-10. Additionally, Astilbe chinensis significantly downregulated gene expression of chemokine receptors CCR1, CCR5 and their ligands CCL3, CCL5 in ALI mouse lung tissues, while upregulating anti-inflammatory markers Arg1 and Ym1 (M2 macrophage biomarkers). Meanwhile, it exerts a notable inhibitory effect on the protein expression of CCR1, CCR5, p-AKT, and p-STAT3.

Conclusion: This study demonstrates that Astilbe chinensis significantly improves lung function and pulmonary inflammation in mice with ALI. Component identification combined with network pharmacology analysis reveals that its major anti-inflammatory components are cyclo(phenylalanyl-prolyl), 5-(6-hydroxy-6- -methyloctyl)-2,5-dihydrofuran-2-one, nicotinamide, 3-phenyllactic acid, and phloretin. The anti-inflammatory mechanism may involve inhibiting the gene and protein expression of inflammatory chemokines CCR1 and CCR5, suppressing the activity of the AKT/STAT3 signaling pathway, reducing the expression of inflammatory factors, promoting M2 macrophage polarization, and thereby increasing the release of anti-inflammatory genes and cytokines, ultimately exerting anti-inflammatory effects.