EGCG (Epigallocatechin Gallate) for Parkinson's Disease
Also known as: Green tea extract, EGCg
EGCG protects dopaminergic neurons through iron chelation and inhibition of α-synuclein aggregation.
Mechanism of Action
EGCG chelates excess iron in the substantia nigra, preventing iron-catalyzed dopamine oxidation. It inhibits α-synuclein fibril formation by redirecting aggregation toward non-toxic amorphous structures. It also modulates microglial activation and activates PKC for neuronal survival signaling.
General mechanism: Tea catechin. Iron chelator, amyloid remodeler, EGFR inhibitor, DNMT inhibitor, Nrf2 activator, proteasome modulator.
Current Evidence
The CHINA-PD trial studied EGCG in early PD — showed initial benefit at 12 months that was not sustained at 24 months. Iron chelation and anti-aggregation effects documented in biomarkers.
Clinical Status: Phase III (CHINA-PD) mixed results. Mechanistic rationale remains strong.
Safety Profile
Generally safe from dietary sources. Hepatotoxicity reported with concentrated supplements >800mg/day. Caffeine interactions possible.
Key Research Questions
- Why did EGCG benefit decline after 12 months in CHINA-PD?
- Can sustained-release EGCG formulations provide longer-lasting neuroprotection?