Astaxanthin Rescues Memory Impairments in Rats with Vascular Dementia by Protecting Against Neuronal Death in the Hippocampus

Abstract

Abstract Background Vascular dementia (VaD) is a cognitive disorder characterized by a decline in cognitive function resulting from cerebrovascular disease. The hippocampus, an important brain region for memory processes, is particularly susceptible to ischemic insults, leading to memory deficits in VaD. Astaxanthin, a carotenoid pigment found in marine organisms, has shown potential therapeutic effects in neurodegenerative diseases. However, the mechanisms underlying its protective effects in VaD and against hippocampal neuronal death remain unclear. Methods In this study, we utilized a rat model of VaD induced by CCH to investigate the therapeutic potential of astaxanthin. Memory impairments were assessed using Y-maze and Morris water maze tests. We also performed biochemical analyses to evaluate levels of hippocampal neuronal death and apoptosis-related proteins, as well as the impact of astaxanthin on the PI3K/Akt/mTOR pathway and oxidative stress. Results Our results demonstrated that astaxanthin significantly rescued memory impairments in VaD rats. Furthermore, astaxanthin treatment protected against hippocampal neuronal death and attenuated apoptosis. We also observed that astaxanthin modulated the PI3K/Akt/mTOR pathway, suggesting its involvement in promoting neuronal survival and synaptic plasticity. Additionally, astaxanthin exhibited antioxidant properties, mitigating oxidative stress in the hippocampus. Conclusions These findings provide valuable insights into the potential therapeutic effects of astaxanthin in VaD. By elucidating the mechanisms underlying the actions of astaxanthin, this study highlights the importance of protecting hippocampal neurons and suggests potential targets for intervention in VaD. Further research is warranted to fully understand the therapeutic potential of astaxanthin and its application in the clinical treatment of VaD.