Preventing H₂O₂-induced toxicity in primary cerebellar granule neurons via activating the PI3-K/Akt/GSK3β pathway by kukoamine from Lycii Cortex

Lycii Cortex (LyC) is widely used as a traditional anti-ageing food ingredient in soup, congee and tea for preventing degenerative disease. However, its bioactive components and modes of action have never been characterized scientifically. The aims of this study are to: 1) examine the neuroprotective effects of LyC against oxidative stress; 2) identify the bioactive components; 3) elucidate the possible molecular mechanisms of the key components. Phytochemical profiling using LC-MS/MS revealed that 7-(4-amino-butoxy)-6-methoxycoumarin, kukoamines A and B, and lyciumins A and B are the major characteristic compounds in LyC. LyC crude extract and kukoamines were effective in preventing cell damage in the H₂O₂-induced primary cerebellar granule neurons (CGNs) model, but kukoamines were more efficacious and potent than the extract. Western blot analysis revealed that KB, the most abundant kukoamine, was capable of inhibiting the neuronal apoptosis via activating the PI3-K/Akt/GSK3β pathway. Thus, our explorative results indicated that kukoamine, the major compounds in LyC, acts as a promising neuroprotectant against the H₂O₂ induced toxicity in CGNs model via activating the PI3-K/Akt/GSK3β pathway. Furthermore, molecular insight to substantiate the application of LyC or kukoamines for prevention and treatment of neurodegenerative diseases in which oxidative stress is involved is demonstrated.