Biodegradable, electroconductive self-healing hydrogel based on polydopamine-coated polyurethane nano-crosslinker for Parkinson's disease therapy

Biomaterials. 2025 Sep:320:123268. doi: 10.1016/j.biomaterials.2025.123268. Epub 2025 Mar 18.

Abstract

Parkinson's disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons, causing motor and neurological impairments. Current treatments offer only temporary symptom relief without halting progression. Herein, a fully biodegradable, electroconductive self-healing hydrogel (CPUD gel) is developed, incorporating electroconductive polydopamine-coated polyurethane nanoparticles (PUD) as crosslinker. The core-shell PUD nanoparticles have a highly uniform size of ∼36 nm with a polydopamine shell of ∼4.8 nm thick on polyurethane core, revealed by small angle X-ray scattering, and own a conductivity of ∼0.82 mS/cm. As nano-crosslinker, the PUD can react with chitosan to form the dynamic CPUD hydrogel with shear modulus (∼280 Pa) and conductivity (∼4.34 mS/cm), mimicking brain tissue properties. In vitro, CPUD gel supports neural stem cell (NSC) proliferation (∼565 %) and differentiation, with elevated neuronal marker expression at 14 days, while exhibiting strong antioxidative and anti-inflammatory effects, rescuing ∼88 % inflamed NSCs. A therapeutic strategy combining injectable CPUD gel with acupuncture in a PD rat model, aiming to activate the innate regenerative mechanisms of body through mobilized endogenous stem cells, is further established. Using this approach, this hydrogel significantly elevates serum TGF-β1/SDF-1 levels, promotes dopaminergic neuron regeneration (>80 %), modulates neuroinflammation through M1-to M2-microglia transition (∼12.6-fold M2/M1 ratio), and improves motor function (from 8 % to 37 % forelimb contacts) in 14 days. Particularly, the electrophysiological spike rate is recovered from 66 to 19 spikes/s, close to the healthy rate 15 spikes/s. The synergistic immunomodulation and neuroprotection highlight the potential of CPUD gel as an advanced therapeutic tool for PD.

Keywords: Acupuncture; Biodegradable hydrogel; Conductive nanoparticle; Parkinson's disease; Polyurethane; Self-healing hydrogel.

MeSH terms

  • Animals
  • Cell Differentiation / drug effects
  • Cell Proliferation / drug effects
  • Cross-Linking Reagents* / chemistry
  • Electric Conductivity
  • Humans
  • Hydrogels* / chemistry
  • Hydrogels* / therapeutic use
  • Indoles* / chemistry
  • Male
  • Nanoparticles* / chemistry
  • Neural Stem Cells / cytology
  • Neural Stem Cells / drug effects
  • Parkinson Disease* / drug therapy
  • Parkinson Disease* / therapy
  • Polymers* / chemistry
  • Polyurethanes* / chemistry
  • Rats
  • Rats, Sprague-Dawley

Substances

  • polydopamine
  • Indoles
  • Polymers
  • Polyurethanes
  • Hydrogels
  • Cross-Linking Reagents