Exploring the Molecular Mechanism by which Kaempferol Attenuates Sepsis-related Acute Respiratory Distress Syndrome Based on Network Pharmacology and Experimental Verification
Authors: Ding Weichao , Huang Changbao , Chen Juan , Zhang Wei , Wang Mengmeng , Ji Xiaohang , Nie Shinan , Sun Zhaorui 
Published: February 2024

Background:
Sepsis-related acute respiratory distress syndrome (ARDS) is a fatal
disease without effective therapy. Kaempferol is a flavonoid compound extracted from natural
plant products; it exerts numerous pharmacological effects. Kaempferol attenuates sepsis-related
ARDS; however, the underlying protective mechanism has not been elucidated completely.

Objective:
This study aimed to use network pharmacology and experimental verification to
investigate the mechanisms by which kaempferol attenuates sepsis-related ARDS.

Methods:
We screened the targets of kaempferol by PharMapper, Swiss Target Prediction, and
CTD database. We identified the targets of sepsis-related ARDS by GeneCards, DisGeNet,
OMIM, and TTD. The Weishengxin platform was used to map the targets of both kaempferol
and sepsis-related ARDS. We created a Venn diagram to identify the intersection targets. We
constructed the "component-intersection targets-disease" network diagram using Cytoscape
3.9.1 software. The intersection targets were imported into the STRING database for developing
the protein-protein interaction network. Metascape was used for the Gene Ontology (GO) and
Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. We selected the
leading 20 KEGG pathways to establish the KEGG relationship network. Finally, we performed
experimental verification to confirm our prediction results.

Results:
Through database screening, we obtained 502, 360, and 78 kaempferol targets, disease
targets of sepsis-related ARDS, and intersection targets, respectively. The core targets consisted of
tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, albumin (ALB), IL-1β, and AKT serine/
threonine kinase (AKT)1. GO enrichment analysis identified 426 items, which were principally
involved in response to lipopolysaccharide, regulation of inflammatory response, inflammatory
response, positive regulation of cell migration, positive regulation of cell adhesion, positive regulation
of protein phosphorylation, response to hormone, regulation of reactive oxygen species (ROS)
metabolic process, negative regulation of apoptotic signaling pathway, and response to decreased
oxygen levels. KEGG enrichment analysis identified 151 pathways. After eliminating the disease
and generalized pathways, we obtained the hypoxia-inducible factor 1 (HIF-1), nuclear factor κB
(NF-κB), and phosphoinositide 3-kinase (PI3K)-Akt signaling pathways. Our experimental verification
confirmed that kaempferol blocked the HIF-1, NF-κB, and PI3K-Akt signaling pathways,
diminished TNF-α, IL-1β, and IL-6 expressions, suppressed ROS production, and inhibited apoptosis
in lipopolysaccharide (LPS)-induced murine alveolar macrophage (MH-S) cells.

Conclusion:
Kaempferol can reduce inflammatory response, ROS production, and cell apoptosis
by acting on the HIF-1, NF-κB, and PI3K-Akt signaling pathways, thereby alleviating sepsis-
related ARDS.