Betulinic acid inhibits pyroptosis in spinal cord injury by augmenting autophagy via the AMPK-mTOR-TFEB signaling pathway

Int J Biol Sci. 2021 Mar 11;17(4):1138-1152. doi: 10.7150/ijbs.57825. eCollection 2021.


Spinal cord injury (SCI) results in a wide range of disabilities. Its complex pathophysiological process limits the effectiveness of many clinical treatments. Betulinic acid (BA) has been shown to be an effective treatment for some neurological diseases, but it has not been studied in SCI. In this study, we assessed the role of BA in SCI and investigated its underlying mechanism. We used a mouse model of SCI, and functional outcomes following injury were assessed. Western blotting, ELISA, and immunofluorescence techniques were employed to analyze levels of autophagy, mitophagy, pyroptosis, and AMPK-related signaling pathways were also examined. Our results showed that BA significantly improved functional recovery following SCI. Furthermore, autophagy, mitophagy, ROS level and pyroptosis were implicated in the mechanism of BA in the treatment of SCI. Specifically, our results suggest that BA restored autophagy flux following injury, which induced mitophagy to eliminate the accumulation of ROS and inhibits pyroptosis. Further mechanistic studies revealed that BA likely regulates autophagy and mitophagy via the AMPK-mTOR-TFEB signaling pathway. Those results showed that BA can significantly promote the recovery following SCI and that it may be a promising therapy for SCI.

Keywords: Betulinic acid; autophagy; mitophagy; pyroptosis; spinal cord injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases / metabolism
  • Animals
  • Anti-Inflammatory Agents, Non-Steroidal / pharmacology
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use*
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / metabolism
  • Betulinic Acid
  • Drug Evaluation, Preclinical
  • Female
  • Mice
  • Mice, Inbred C57BL
  • Mitophagy / drug effects*
  • Pentacyclic Triterpenes / pharmacology
  • Pentacyclic Triterpenes / therapeutic use*
  • Pyroptosis / drug effects*
  • Recovery of Function / drug effects
  • Signal Transduction / drug effects
  • Spinal Cord Injuries / drug therapy*
  • Spinal Cord Injuries / metabolism
  • TOR Serine-Threonine Kinases / metabolism


  • Anti-Inflammatory Agents, Non-Steroidal
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • Pentacyclic Triterpenes
  • Tcfeb protein, mouse
  • mTOR protein, mouse
  • TOR Serine-Threonine Kinases
  • AMP-Activated Protein Kinases
  • Betulinic Acid