Integrative systems pharmacology and experimental Assessment of hyaluronic Acid-Curcumin conjugate in an Alzheimer's disease model

Curcumin exhibits potent neuroprotective activity but is limited by poor solubility and limited bioavailability. Conjugation with hyaluronic acid (HA), a biocompatible polysaccharide, may improve the stability, therapeutic efficacy and bioavailability of curcumin.

Network pharmacology, Gene Ontology (GO), and KEGG pathway enrichment analysis revealed curcumin and hyaluronic acid - associated Alzheimer's disease (AD) targets and pathways. Docking and molecular dynamic studies were performed to evaluate protein-ligand interactions. The Hyaluronic acid-curcumin (HA-Cur) conjugate was synthesized through carbodiimide-mediated coupling using DCC and DMAP, purified by dialysis and lyophilized. Characterization was performed using FTIR, UV-visible spectroscopy, solubility, drug release and SEM analyses. In vivo validation used C. elegans CL4176 for Aβ-induced paralysis assay and N2 wild type strain for developmental assay and paraquat induced lifespan assay. Worms were treated with curcumin (1 mg), hyaluronic acid (1 mg), HA-Cur conjugate (0.01, 0.1 and 1 mg/mL), caffeine (Positive standard) and DMSO (Control). Developmental progression from L1 to adulthood was assessed by body length.

Network pharmacological analysis revealed 52 overlapping HA and curcumin associated AD, therapeutic targets, highlighting GSK3B, APP, SERPINE and NFE2L2 as key nodes. Molecular docking demonstrated strong binding affinities of curcumin (GSK3B: -7.7 kcal/mol) and hyaluronic acid (NFE2L2: -7.0 kcal/mol). Molecular dynamics simulation over 100 ns demonstrated stable protein-ligand interactions for both complexes. The conjugate showed enhanced solubility and sustained drug release. HA-Cur (1 mg) notably delayed Aβ-induced paralysis, ∗∗p < 0.01 and ∗∗∗p < 0.001 compared with curcumin and HA respectively. Enhanced survival under paraquat - induced oxidative stress compared to free curcumin and HA and promoted normal developmental progression.

The HA-Cur conjugate exhibited enhanced physicochemical stability and potent neuroprotective and developmental benefits in C. elegans, highlighting its potential as a multifunctional therapeutic agent for AD.