Repeated intra-hippocampal injection of beta-amyloid 25–35 induces a reproducible impairment of learning and memory: Considering caspase-3 and MAPKs activity

Endocannabinoid 2-arachidonylglycerol protects primary cultured neurons against homocysteine-induced impairments in rat caudate nucleus through CB1 receptor

Homocysteine (Hcy) is a high risk factor for Alzheimer's disease (AD). Caudate nucleus (CN), the major component of basal ganglia in the brain, is also involved in many neurological disorders. 2-Arachidonoylglycerol (2-AG), the true natural ligand for cannabinoid type-1 (CB1) receptors and the most abundant endogenous cannabinoid, has been shown to exhibit neuroprotective effects through its anti-inflammatory action from proinflammatory stimuli in the hippocampus and CN. However, it is still not well understood whether that 2-AG is also able to protect CN neurons from Hcy harmful insults. In the present work, we explored that 2-AG significantly protects CN neurons in culture against Hcy-induced response. 2-AG is capable of inhibiting elevation of Hcy-induced cyclooxygenase-2 expression associated with nuclear factor-kappaB/p38MAPK/ERK1/2 signaling pathway through CB1 receptors-dependent way in primary cultured CN neurons. Our study reveals the therapeutic potential for 2-AG for the treatment of neurodegenerative diseases, such as AD.

l-3-n-Butylphthalide attenuates β-amyloid-induced toxicity in neuroblastoma SH-SY5Y cells through regulating mitochondrion-mediated apoptosis and MAPK signaling

Alzheimer's disease (AD) is a progressive neurodegenerative disease. Amyloid-β protein (Aβ), the hallmark of AD, invokes a cascade of mitochondrial dysfunction and eventually leads to neuronal death. l-3-n-Butylphthalide (l-NBP) has shown the potent neuroprotective effects in stroke and AD animal models. The present study is to evaluate the neuroprotective effect of l-NBP on Aβ25-35-induced neuronal injury and the possible mechanism in the human neuroblastoma SH-SY5Y cells. Our results showed that l-NBP significantly attenuated Aβ25-35-induced cell death and reduced neuronal apoptosis. l-NBP significantly inhibited Aβ25-35-induced mitochondrial dysfunction, including mitochondrial membrane potential reduction, and reactive oxygen species production. Furthermore, l-NBP could partially reverse the elevations of Aβ25-35-induced active caspase-3, caspase-9, and cytochrome c expressions, and the downregulation of anti-apoptosis protein Bcl-2. Moreover, l-NBP markedly inhibited the activations of p38 mitogen-activated protein kinase and c-Jun N-terminal kinase/stress-activated protein kinase signaling pathway. These results demonstrated that l-NBP was capable of protecting neuronal cells from Aβ25-35-induced toxicity through a mitochondrial-dependent apoptotic pathway. Thus, l-NBP shows promising candidate of multi-target neuronal protective agent for the treatment of AD.