Brown rice attenuates iron-induced Parkinson’s disease phenotypes in male wild-type <i>drosophila</i>: insights into antioxidant and iron metabolism modulation

Parkinson's disease (PD) is a progressive movement disorder associated with brain iron (Fe) accumulation and free radicals. Brown rice (BR) is antioxidant-rich and has been shown to ameliorate oxidative stress-induced damage. The aim of this study was to investigate the effects of BR compared to white rice (WR) on Fe-induced PD in a fruit fly model. Three-day-old male adult flies were divided into two groups: one on a normal diet and the other on Fe-diet (1 mmol/L) for 10 days to induce PD. After 10 days, the Fe-fed flies were redistributed into four groups: one on normal diet (Fe group), while the others were treated with BR (Fe + BR group), WR (Fe + WR group), or L-3,4-dihydroxyphenylalanine (L-dopa) (Fe + L-dopa group) for 5 days. Similarly, the flies initially on a normal diet were separated into four groups: one on normal diet (Control group), while the others were treated with BR (BR group), WR (WR group), or L-dopa (L-dopa group) for 5 days. Finally, Fe levels, dopamine, malonaldehyde (MDA), and antioxidant enzymes were measured, and the mRNA levels of antioxidant and Fe metabolism genes were assessed. BR significantly improved motor and cognitive functions, decreased fly head MDA and Fe levels, and increased antioxidant enzyme levels in comparison to the Fe and WR groups. Similarly, BR upregulated the mRNA levels of antioxidant genes: catalase, GPx, Nrf2, and DJ-1. The results suggest that BR could potentially reduce morbidities associated with PD possibly due to its bioactive compounds compared to WR.