Scutellaria baicalensis Pith-decayed Root Inhibits Macrophage-related Inflammation Through the NF-κB/NLRP3 Pathway to Alleviate LPS-induced Acute Lung Injury

Abstract

Acute lung injury (ALI) is one of the representative “lung heat syndromes” in traditional Chinese medicine (TCM). Scutellaria baicalensis is a herbal medicine used in TCM for treating lung diseases due to its remarkable anti-inflammatory and antiviral effects. When used in TCM, S. baicalensis root is divided into two categories: S. baicalensis pith-not-decayed root (SN) and S. baicalensis pith-decayed root (SD). Compared to SN, SD has a better effect on lung diseases. We constructed a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model to study the pharmacodynamic mechanism of SD. The ethanolic extract of Scutellaria baicalensis pith-decayed root (EESD) significantly affected LPS-induced ALI by reducing alveolar interstitial thickening, pulmonary edema, and other pathological symptoms, decreasing the infiltration of inflammatory cells, especially macrophages, and inhibiting IL-1β, TNF-α, and IL-6 transcription and translation. Furthermore, in the THP-1 macrophage model induced by LPS, EESD inhibited the expression of phosphorylated nuclear factor inhibitory protein alpha (p-IκBα), phosphorylated nuclear factor-κB P65 (p-p65), cleaved-caspase-1, cleaved-IL-1β protein, and the release of inflammatory factors in the NF-κB/NLRP3 pathway, inhibiting macrophage function. In vivo experiments yielded similar results. Therefore, the present study clarified the potential of EESD in the treatment of ALI and revealed its potential pharmacodynamic mechanism by inhibiting the NF-κB/NLRP3 inflammasome pathway and suppressing the pro-inflammatory phenotype activation of lung tissue macrophages.

Network Pharmacology and Experimental Verifications to Discover Scutellaria baicalensis Georgi’s Effects on Joint Inflammation, Destruction, and Pain in Osteoarthritis

“…Firstly, the anti-inflammatory and antioxidant activities of SB that inhibit the progressive pathology of OA should be examined in greater detail. The anti-inflammatory activity of SB is well established [18,26,27,43]. In contrast, the antioxidant activity of SB mediates protective effects in biological tissues, such as myocardial damage in myocardial ischemia and the inhibition of oxidative stress-induced liver injury; its antioxidant capacity is also stronger than that of other widely studied materials [24,28,44,45].…”

The Extract of Scutellaria baicalensis Attenuates the Pattern Recognition Receptor Pathway Activation Induced by Influenza A Virus in Macrophages

“…There are few studies on the effect of SBE on influenza virus-infected human macrophages. In the LPS-induced THP-1 macrophage model, Scutellaria baicalensis pith-decayed root reduced caspase-1 activation and IL-1 expression by inhibiting the NF-κB/NLRP3 pathway [ 63 ]. We propose that further studies in humans are needed to decipher the role of SBE against influenza virus-induced innate immunity, particularly in macrophages.…”