Decoding Macrophage Subtypes to Engineer Modulating Hydrogels for the Alleviation of Intervertebral Disk Degeneration
Da-Wang Zhao1, Qian Cheng2, Huimin Geng2
1Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong, 250012, China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|November 8, 2023
Summary
This study developed an injectable hydrogel to treat intervertebral disk degeneration by balancing extracellular matrix metabolism. The hydrogel modulates macrophage phenotypes, promoting tissue repair and reducing degeneration.
Area of Science:
- Biomaterials Science
- Regenerative Medicine
- Orthopedics
Background:
- Intervertebral disk degeneration, a cause of low back pain, stems from nucleus pulposus cell issues and extracellular matrix (ECM) metabolic imbalance.
- Macrophage phenotype critically influences ECM metabolism, making macrophage modulation a potential therapeutic strategy for disk degeneration.
Purpose of the Study:
- To develop an injectable nanocomposite hydrogel for intervertebral disk degeneration (IDD) treatment.
- To investigate the hydrogel's ability to modulate macrophage phenotype and restore ECM balance.
Main Methods:
- Prepared an injectable hydrogel embedding epigallocatechin-3-gallate-coated hydroxyapatite nanorods in O-carboxymethyl chitosan.
- Utilized aldehyde hyaluronic acid for cross-linking, creating a system capable of macrophage phenotype modulation.
- Evaluated the hydrogel's effects on ECM metabolism, mesenchymal stem cell differentiation, and macrophage polarization in vitro and in vivo.
Main Results:
- Hydroxyapatite nanorods promoted ECM anabolism via mesenchymal stem cell differentiation.
- Epigallocatechin-3-gallate induced M2 macrophage polarization, reducing ECM catabolism and alleviating degeneration.
- The hydrogel system effectively controlled ECM anabolism/catabolism and inhibited the M1-related IL17 pathway.
Conclusions:
- The developed injectable nanocomposite hydrogel offers a promising minimally invasive treatment for intervertebral disk degeneration.
- Modulating macrophage phenotype and restoring ECM metabolic balance are key to repairing degenerated intervertebral disks.
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