Butyrate-Modified Hyaluronic Acid Ameliorates MPTP-Induced Parkinson's Disease via Modulating PINK1/Parkin-Involved Mitophagy and Intestinal Flora.

Parkinson's disease (PD) is difficult to treat clinically and lacks an effective treatment. The aim of this study was to synthesize and characterize butyrate-modified hyaluronic acid (HA-But), validate its therapeutic efficacy, and elucidate its mechanisms of action in PD. Behavioral tests, including the open field test, Y-maze, and elevated plus maze test, demonstrated that HA-But significantly alleviated motor dysfunction in PD mice. ELISA results indicated a marked reduction in pro-inflammatory cytokine levels following the HA-But treatment. In addition, immunohistochemistry, immunofluorescence, and Western blot analyses revealed that HA-But improved dopaminergic neuron survival and reduced α-synuclein aggregation. Furthermore, HA-But activated PINK1/Parkin-mediated mitophagy, modulated gut microbiota composition, and increased short-chain fatty acid (SCFA) levels, especially butyric acid. Combining HA-But with gastrodin further improved the PD symptoms in mice. These findings suggested the potential of HA-But as a novel approach for PD treatment.