Exposure to aluminum (Al) and its compounds is an environmental factor that induces neurotoxicity, partially through oxidative stress, potentially leading to the development of neurodegenerative diseases. Components of the diet, such as caffeinated coffee, may play a significant role in preventing these diseases. In the present study, an experimental model of PC12 cells (rat pheochromocytoma tumor cells) was developed to investigate the influence of caffeine and caffeinated coffee on neurotoxicity induced by Al compounds and/or oxidative stress. For the induction of neurotoxicity, aluminum maltolate (Almal) and H2O2 were used. The present study demonstrates that 100 μM Almal reduced cell survival, while caffeinated coffee with caffeine concentrations of 5 μg/mL and 80 μg/mL reversed this effect, resulting in a higher than fivefold increase in PC12 cell survival. However, despite the observed antioxidant properties typical for caffeine and caffeinated coffee, it is unlikely that they are the key factors contributing to cell protection against neurotoxicity induced by both oxidative stress and Al exposure. Moreover, the present study reveals that for coffee to exert its effects, it is possible that Al must first activate certain mechanisms within the cell. Therefore, various signaling pathways are discussed, and modifications of these pathways might significantly decrease the risk of Al-induced neurotoxicity.
Keywords: aluminum; caffeine; coffee; neurodegeneration; neurodegenerative diseases; neurotoxicity; oxidative stress.