Injectable chitosan/maltodextrin/microcrystalline cellulose hydrogels loaded with melatonin for intervertebral disc...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Orthopedics

Background:

• Intervertebral disc degeneration is a prevalent condition with limited regenerative capacity.
• Current treatments for disc degeneration primarily manage symptoms rather than restore function.
• Injectable hydrogels are emerging as promising therapeutic strategies for intervertebral disc regeneration.

Purpose of the Study:

• To develop and characterize an injectable melatonin-loaded hydrogel for intervertebral disc regeneration.
• To evaluate the impact of oxidized microcrystalline cellulose (ox-MCC) on hydrogel properties and performance.
• To assess the biocompatibility and therapeutic potential of the melatonin-loaded hydrogel using nucleus pulposus cells.

Main Methods:

• Fabrication of an injectable hydrogel composite from chitosan (CS), oxidized maltodextrin (ox-MD), and oxidized microcrystalline cellulose (ox-MCC).
• Characterization of hydrogel properties including gelation time, degradation, mechanical strength (Young's modulus), and melatonin release kinetics.
• In vitro assessment of hydrogel cytotoxicity, cell proliferation, and glycosaminoglycan synthesis using bovine nucleus pulposus (NP) cells.

Main Results:

• Incorporation of ox-MCC significantly reduced gelation time and improved hydrogel weight retention during degradation.
• Increasing ox-MCC content enhanced hydrogel mechanical properties, with a six-fold increase in Young's modulus.
• Melatonin-loaded hydrogels demonstrated non-toxicity, supported NP cell proliferation, and significantly increased glycosaminoglycan synthesis, with the highest levels observed in the melatonin-loaded formulation.

Conclusions:

• The developed injectable melatonin-loaded hydrogel, incorporating ox-MCC, exhibits favorable physicochemical and mechanical properties.
• The hydrogel formulation is biocompatible and effectively promotes nucleus pulposus cell proliferation and extracellular matrix synthesis.
• This melatonin-loaded hydrogel holds significant potential as a therapeutic agent for intervertebral disc regeneration.