Biancaea decapetala (Roth) O.Deg. extract exerts an anti-inflammatory effect by regulating the TNF/Akt/NF-κB pathway

Biancaea decapetala (Roth) O.Deg. (Fabaceae) is used to treat colds, fever, and rheumatic pain caused by inflammation. However, the mechanism underlying its anti-inflammatory properties remains unclear.

This study aimed to evaluate the anti-inflammatory activity of Biancaea decapetala extract (BDE) in vitro and in vivo and explore the possible underlying mechanism and potential targets.

The release of nitric oxide (NO) and inflammatory cytokines in LPS-stimulated RAW264.7 cells and rats were measured using Griess reagent and enzyme-linked immunosorbent assay (ELISA). Hematoxylin and eosin (H&E) staining was employed to examine the pathology of animal tissues. Transcriptome analysis was performed to screen the pathways related to BDE-mediated inhibition of inflammation, and the expression of related proteins was measured using real-time quantitative polymerase chain reaction (RT-qPCR), western blotting, ELISA, and immunofluorescence methods. Surface Plasmon Resonance (SPR) and the Drug Affinity Reaction Target Stability (DARTS) method were used to verify whether BDE binds to TNF-α target protein, while a L929 cell model and NF-κB gene reporter systematic method were used to investigate the inhibitory effect of BDE on the activity of TNF-α protein.

BDE inhibited the expression of TNF-α, IL-1β, IL-6, and NO in RAW264.7 cells and rats, and improved the pathological changes in lung tissue. RNA-seq showed that BDE may regulate the TNF/Akt/NF-κB pathway to inhibit inflammation onset. BDE significantly downregulated the mRNA expression of TNF-α, IL-6, IL-1β, and that of relevant proteins, including TNF-α, p-p65, p-Akt, p-IκBα. Furthermore, BDE inhibited the nuclear translocation of NF-κB (p65) and the activation of the Akt pathway by SC79. The L929 cell model, luciferase reporter gene analysis, DARTS, and SPR experiments showed that BDE may bind to TNF-α and inhibit the TNF-α-NF-κB pathway.

BDE may target TNF-α to inhibit the TNF/Akt/NF-κB pathway, thereby attenuating inflammation. These findings reveal the anti-inflammatory effects and mechanisms of BDE and provide a theoretical basis for the further development and utilization of BDE.