A Single-Cell-Inspired Self-Enrichment Therapeutic Strategy Delays Intervertebral Disc Degeneration by Inhibiting...

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Nanotechnology

Background:

• Intervertebral disc degeneration (IVDD) is a leading cause of spinal surgery, with current treatments unable to halt or reverse its progression due to poor drug delivery and limited mechanistic understanding.
• Degenerative tissues exhibit a fibrotic barrier hindering therapeutic access, and nucleus pulposus cells undergo pyroptosis driven by STING-mediated inflammation.
• A comprehensive cellular atlas is needed to understand IVDD mechanisms and develop targeted therapies.

Purpose of the Study:

• To construct a cellular atlas for IVDD by integrating single-cell transcriptomics and clinical data.
• To identify key mechanisms driving IVDD, including fibrotic barriers and pyroptosis.
• To develop and validate a novel nanocarrier system for targeted drug delivery to degenerated intervertebral discs.

Main Methods:

• Single-cell transcriptomics and clinical validation were used to create a cellular atlas of IVDD.
• A self-enriching nanocarrier (Motor@TA-siRNA) was designed to overcome fibrotic barriers via bubble propulsion.
• Small interfering ribonucleic acid (siRNA) was incorporated for targeted delivery to the STING pathway, inhibiting inflammation and pyroptosis.

Main Results:

• The study identified a fibrotic barrier in degenerative discs impeding drug delivery.
• Pyroptosis in nucleus pulposus cells, mediated by STING, was confirmed as a key inflammatory mechanism.
• The Motor@TA-siRNA nanocarrier demonstrated selective penetration into degenerated tissues and effectively inhibited STING-mediated inflammation and pyroptosis.
• In vitro and in vivo studies confirmed the nanocarrier's biocompatibility and efficacy in delaying IVDD progression.

Conclusions:

• A synergistic strategy combining mechanistic insight and nanocarrier design offers a promising approach for IVDD therapy.
• The developed nanocarrier system effectively targets the STING pathway, mitigating inflammation and pyroptosis.
• This study provides a foundation for personalized IVDD treatment by addressing key pathological features and improving drug delivery.