Cerebrosides from Sea Cucumber Improved Aβ 1-42 -Induced Cognitive Deficiency in a Rat Model of Alzheimer's Disease

Cerebrosides are a class of neutral glycosphingolipids, which are widely found to be present in brain tissue. In this study, the protective effect of sea cucumber cerebrosides (Cer) against β-amyloid (Aβ)-induced cognitive impairment is investigated. Male SD rats receive a ventricle injection Aβ peptide to establish an Alzheimer's disease model. Then, the protective effects of Cer against Aβ -induced cognitive impairment by gavage and feed addition are evaluated. The Morris water maze test results show that oral administration of Cer can significantly ameliorate Aβ -induced cognitive deficiency at both high dose (200 mg per kg·per day) and low dose (40 mg per kg·per day) for 27 days. Dietary supplement of Cer by feed addition also exhibits the amelioration on the impaired cognitive function. Further findings indicate that Cer ameliorates Aβ -induced neuronal damage and suppresses the induced apoptosis by decreasing the level of Bax/Bcl-2. Additionally, Cer enhances the expressions of PSD-95 and synaptophysin by activating BDNF/TrkB/CREB signaling pathway, thereby ameliorating Aβ -induced synaptic dysfunction. Furthermore, Cer attenuates Aβ -induced tau hyperphosphorylation by activating the PI3K/Akt/GSK3β signaling pathway. Sea cucumber cerebrosides possess neuroprotective effects against Aβ -triggered cognitive deficits, which may be a potential nutritional preventive strategy for neurodegenerative diseases.