Guarana (Paullinia cupana): Cytoprotective effects on age-related eye dysfunction

Ageing can cause disorders such as age-related macular degeneration (AMD), which leads to irreversible visual loss in elderly people. Given that nutrition may influence some age-related disorders, this study investigated, in vivo, the association between self-reported eyesight quality and daily guarana intake in riparian elderly subjects and, in vitro, the effects of guarana (Paullinia cupana) on retinal pigmented epithelium (RPE) cells exposed to paraquat. Just over half of the elderly subjects self-reported poor vision (n = 320, 50.8%), 234 (37.1%) self-reported regular eyesight, whereas just 76 (12.1%) self-reported good vision. Subjects that self-reported good vision presented a higher frequency of habitual guarana consumption. Guarana treatment was able to decrease apoptosis and necrosis events and differentially modulate gene expression and protein levels of caspases 1, 3 and 8 in RPE cells. This work provides new perspectives on the potential use of guarana against eye diseases due to its cytoprotective effects.