Effect of Brown Rice on PINK1/Parkin-Mediated Mitophagy in a Drosophila Model of Iron-Induced Parkinson’s Disease

Background: Parkinson’s disease (PD) involves the progressive loss of dopaminergic neurons and is linked to brain iron accumulation and free radicals. Brown rice (BR) possesses antioxidant properties that may help mitigate oxidative stress-related damage. This study aimed to compare the effects of BR against WR on iron-induced PD in a fruit fly model. Materials and Methods: Adult fruit flies were divided into five groups and fed an iron-supplemented diet for 10 days to induce oxidative stress. The groups were then given different diets for 5 days: normal, iron-only, BR + iron, white rice (WR) + iron, and L-dopa + iron diets. Behavioural tests (motor function, memory, anxiety), iron, dopamine, malondialdehyde (MDA), and antioxidant enzyme levels were measured, along with the expression of antioxidant genes (CAT, GPx and NRF2), iron metabolism-related genes (ferritin and DMT-1) and autosomal activity-related genes (PINK1/PARKIN). Results: BR improved motor and cognitive functions, reduced MDA and iron levels, and increased antioxidant enzyme levels compared to the iron-only and WR groups. BR also upregulated the expression of antioxidant and iron metabolism genes, and positively affected the expression of the PINK1/PARKIN genes. These findings suggest BR could be developed as a complementary dietary supplement in combination with standard PD treatments. Conclusion: BR may be beneficial as a therapeutic dietary intervention for PD by reducing motor/non-motor symptoms and regulating PINK1/Parkin-mediated mitophagy.