Protective Effect of Piplartine against LPS-Induced Sepsis through Attenuating the MAPKs/NF-κB Signaling Pathway and NLRP3 Inflammasome Activation

• Main Authors: Chi-Han Huang, Shu-Chi Wang, I-Chen Chen, Yi-Ting Chen, Po-Len Liu, Shih-Hua Fang, Shu-Pin Huang, Hsin-Chih Yeh, Ching-Chih Liu, Po-Yen Lee, Tzu-Chieh Lin, Wei-Chung Cheng, Chia-Cheng Su, Hsin-En Wu, Yuan-Ru Chen, Chia-Yang Li
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: Pharmaceuticals
• Subjects: piplartine; macrophage; inflammation; NLRP3 inflammasome; sepsis
• Online Access: https://www.mdpi.com/1424-8247/14/6/588

Piplartine (or Piperlongumine) is a natural alkaloid isolated from <i>Piper longum</i> L., which has been proposed to exhibit various biological properties such as anti-inflammatory effects; however, the effect of piplartine on sepsis has not been examined. This study was performed to examine the anti-inflammatory activities of piplartine in vitro, ex vivo and in vivo using murine J774A.1 macrophage cell line, peritoneal macrophages, bone marrow-derived macrophages and an animal sepsis model. The results demonstrated that piplartine suppresses iNOS and COX-2 expression, reduces PGE₂, TNF-α and IL-6 production, decreases the phosphorylation of MAPKs and NF-κB and attenuates NF-κB activity by LPS-activated macrophages. Piplartine also inhibits IL-1β production and suppresses NLRP3 inflammasome activation by LPS/ATP- and LPS/nigericin-activated macrophages. Moreover, piplartine reduces the production of nitric oxide (NO) and TNF-α, IL-6 and IL-1β, decreases LPS-induced tissue damage, attenuates infiltration of inflammatory cells and enhances the survival rate. Collectively, these results demonstrate piplartine exhibits anti-inflammatory activities in LPS-induced inflammation and sepsis and suggest that piplartine might have benefits for sepsis treatment.