Work

Ma Xing Shi Gan Decoction alleviates lipopolysaccharide-induced pneumonia by inhibiting NLRP3 inflammasome activation via AMPK/mTOR/ULK1-mediated autophagy

Year: 2025

Type: article

Abstract: ETHNOPHARMACOLOGICAL RELEVANCE: Pneumonia represents a common acute respiratory infection that presents a major health concern worldwide. The Ma Xing Shi Gan Decoction (MXSG) is a famous formulation utilized for respiratory ailments for millennia and celebrated for its impressive therapeutic benefits. However, the specific mechanism of MXSG alleviating pneumonia remains unclear. AIM OF THE STUDY: This research aimed to investigate the involvement of the NLRP3 inflammasome and autophagy in pneumonia induced by lipopolysaccharide (LPS), and to examine the therapeutic mechanisms associated with MXSG. MATERIALS AND METHODS: The principal MXSG components were characterized through the application of high-performance liquid chromatography coupled with mass spectrometry. To investigate how MXSG impacts the inflammatory response and autophagy, and NLRP3 inflammasome activation, a rat model of pneumonia was created via LPS inhalation. Additionally, LPS-stimulated J774A.1 macrophages were utilized for in vitro investigations. Furthermore, the processes through which MXSG promotes autophagy and subsequently suppresses excessive NLRP3 inflammasome activation were examined utilizing 3-methyladenine (3-MA, which inhibits autophagy), compound C (CC, an inhibitor of AMPK), and siAMPK (siRNA targeting AMPK). To evaluate the binding affinity of the primary active compounds in MXSG with the essential proteins associated with autophagy, molecular docking studies were conducted. RESULTS: A comprehensive analysis revealed the identification of 828 active compounds within MXSG. In vivo, MXSG significantly alleviated lung inflammation in rats with pneumonia induced by LPS. The mechanism included improving autophagy and the subsequent inhibition of excessive NLRP3 inflammasome activation via the AMPK/mTOR/ULK1 pathway. Notably, 3-MA and CC greatly reduced the suppressive impact of MXSG on NLRP3 inflammasome activation. Molecular docking revealed that the active compounds of MXSG (amygdalin, licoricesaponin G2, and daidzein) exhibited high binding affinities to autophagy-related proteins (AMPK, mTOR, and ULK1). In vitro, MXSG demonstrated anti-inflammatory properties in LPS-activated J774A.1 macrophages and suppressed excessive NLRP3 inflammasome activation by promoting autophagy. Similarly, silencing AMPK genes notably diminished the suppressive effects of MXSG on NLRP3 inflammasome activation. This confirms that MXSG enhances autophagy and inhibits NLRP3 inflammasome activation is dependent on the AMPK/mTOR/ULK1 pathway. CONCLUSION: MXSG activates the AMPK/mTOR/ULK1 pathway, promoting autophagy and inhibiting excessive NLRP3 inflammasome activation induced by LPS. This subsequently reduces inflammatory cytokine (IL-1β, IL-18) levels, thereby mitigating LPS-triggered lung inflammation. The primary active compounds of MXSG that promote autophagy are amygdalin, licoricesaponin G2, and daidzein. These findings offer fresh perspectives on how MXSG mitigates pneumonia, highlighting the anti-inflammatory effects, and reveal potential therapeutic targets for future use in integrative medicine.

Source: Journal of Ethnopharmacology

DOI: 10.1016/j.jep.2025.120418