Injectable pathological microenvironment-responsive anti-inflammatory hydrogels for ameliorating intervertebral disc
Lei Liu1, Wantao Wang2, Lin Huang1
1Guangdong Provincial Key Laboratory of Advanced Biomaterials, Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, 518055, China.
Biomaterials
|February 20, 2024
Summary
This study introduces an injectable hydrogel that releases anti-inflammatory drugs in response to the intervertebral disc degeneration (IDD) microenvironment. This approach promotes nucleus pulposus (NP) cell repair and preserves disc structure in IDD models.
Area of Science:
- Biomaterials Science
- Regenerative Medicine
- Drug Delivery Systems
Background:
- Chronic inflammation and nucleus pulposus (NP) cell dysfunction drive intervertebral disc degeneration (IDD).
- Injectable, microenvironment-responsive hydrogels offer potential for IDD treatment by adapting to the dynamic pathological milieu.
Purpose of the Study:
- To develop an injectable, pathological microenvironment-responsive hydrogel for controlled release of an anti-inflammatory drug to treat IDD.
- To promote degenerative NP cell repair and preserve disc integrity.
Main Methods:
- Synthesized a gelatin-based hydrogel by conjugating phenylboronic acid-modified gelatin methacryloyl (GP) with epigallocatechin-3-gallate (EGCG) via dynamic boronic esters.
- Evaluated hydrogel properties including degradability, injectability, antioxidant and anti-inflammatory effects, and biocompatibility.
- Assessed EGCG release under high reactive oxygen species (ROS) and acidic conditions, and evaluated cytoprotective effects on NP cells in vitro. Conducted in vivo studies using a rat IDD model.
Main Results:
- The hydrogel demonstrated excellent degradability, injectability, antioxidant, anti-inflammatory, and biocompatible properties.
- EGCG release was responsive to high ROS levels and acidic conditions, characteristic of the IDD pathological microenvironment.
- In vitro, the hydrogel protected NP cells from oxidative stress and inflammatory cytokines. In vivo, it ameliorated IDD, maintaining disc height and NP tissue structure.
Conclusions:
- The developed hydrogel system exhibits biocompatibility and responsive drug release in pathological microenvironments.
- This hydrogel platform shows significant potential for treating intervertebral disc degeneration by delivering anti-inflammatory drugs effectively.
- The system's ability to adapt to the IDD microenvironment and promote NP repair highlights its promise as an advanced drug delivery platform.
Keywords:
Gelatin hydrogelInflammatory regulationIntervertebral disc degeneration repairMinimally invasive injectionResponsive releaseMore Related Videos
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