Exploring the Combined Effect of Exercise and Apigenin on Aluminium-Induced Neurotoxicity in Zebrafish

Aluminium (AL) is a strong environmental neurotoxin linked to neurodegenerative disorders. Widespread industrial use leads to its presence in water systems, causing bioaccumulation in organisms. This, in turn, results in the bioaccumulation of AL in various organisms. Several studies have highlighted the benefits of enhanced physical activity in combating neurodegenerative diseases. Meanwhile widespread presence of apigenin in aquatic environment has been largely overlooked, in terms of its potential to counter AL-induced neurotoxicity. The combined impact of exercise and apigenin in mitigating the effects of AL-induced neurotoxicity in aquatic animals remains unexplored. Hence, the objective of this study is to determine whether the combined treatment of exercise and apigenin can effectively alleviate the chronic neurotoxicity induced by AL. Zebrafish that were exposed to AL showed behaviours resembling anxiety, increased aggression, unusual swimming pattern, and memory impairment, which are typical features observed in Alzheimer's disease (AD)-like syndrome. Combined treatment of exercise and apigenin protects zebrafish from AL-induced neurotoxicity, which was measured by improvements in memory, reduced anxiety and aggression, and increased levels of antioxidant enzymes and acetylcholinesterase (AChE) activity. Furthermore, AL exposure is associated with increased expression of genes related to neuroinflammation and AD. However, synergistic effect of exercise and apigenin counteract this effect in AL-treated zebrafish. These findings suggest that AL is involved in neurodegenerative diseases in fish, which could affect the integrity of aquatic ecosystem. Hence, there is a strong correlation between enhanced physical activity, apigenin, and the well-being of the ecosystem.