ABSTRACT
AIM: 1,1'-([1,1'-Biphenyl]-4,4'-diyl)bis(3-(piperidin-1-yl)propan-1-one)dihydrochloride (DL0410) is a novel synthetic dual acetylcholinesterase (AChE)/butyrocholinesterase (BuChE) inhibitor, which has shown a potential therapeutic effect on Alzheimer's disease (AD). In this study we examined whether DL0410 produced neuroprotective effects in an AD cellular model and an Aß1-42-induced amnesia mouse model. METHODS: The in vitro inhibitory activities against AChE and BuChE were estimated using Ellman's assay. Copper-induced toxicity in APPsw-SY5Y cells was used as AD cellular model, the cell viability was assessed using MTS assay, and cell apoptosis was evaluated based on mitochondrial membrane potential detection. Aß1-42-induced amnesia mouse model was made in male mice by injecting aggregated Aß1-42 (2 µg in 2 µL 0.1% DMSO) into the right cerebral ventricle. Before and after Aß1-42 injection, the mice were orally administered DL0410 (1, 3, 9 mg·kg-1·d-1) or rivastigmine (2 mg·kg-1·d-1) for 3 and 11 d, respectively. Memory impairments were examined using Morris water maze (MWM) test and passive avoidance test. The expression levels of APP, CREB, BDNF, JNK and Akt in the mouse brains were measured with either immunohistochemistry or Western blotting. RESULTS: DL0410 exhibited in vitro inhibitory abilities against AChE and BuChE with IC50 values of 0.286±0.004 and 3.962±0.099 µmol/L, respectively, which were comparable to those of donepezil and rivastigmine. In APPsw-SY5Y cells, pretreatment with DL0410 (1, 3, and 10 µmol/L) decreased the phosphorylation of JNK and increased the phosphorylation of Akt, markedly decreased copper-stimulated Aß1-42 production, reversed the loss of mitochondrial membrane potential, and dose-dependently increased the cell viability. In Aß1-42-treated mice, DL0410 administration significantly ameliorated learning and memory deficits in MWM test and passive avoidance test. Furthermore, DL0410 administration markedly decreased Aß1-40/42 deposits in mouse cerebral cortices, and significantly up-regulated neurotrophic CREB/BDNF. Meanwhile, Akt/JNK signaling pathway may play a key role in the neuroprotective effect of DL0410. CONCLUSION: DL0410 ameliorates cognitive deficit and exerts neuronal protection in AD models, implicating this compound as a candidate drug for the prevention and therapy of AD.
Subject(s)
Amyloid beta-Peptides/toxicity , Biphenyl Compounds/pharmacology , Brain/drug effects , Cholinesterase Inhibitors/pharmacology , Memory Disorders/drug therapy , Neurons/drug effects , Neuroprotective Agents/pharmacology , Peptide Fragments/toxicity , Piperidines/pharmacology , Acetylcholinesterase/metabolism , Alzheimer Disease/drug therapy , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Animals , Apoptosis/drug effects , Avoidance Learning/drug effects , Brain/pathology , Butyrylcholinesterase/metabolism , Cell Line, Tumor , Cerebral Cortex/drug effects , Cerebral Cortex/pathology , Cholinesterase Inhibitors/therapeutic use , Donepezil , Indans/pharmacology , JNK Mitogen-Activated Protein Kinases/metabolism , Male , Maze Learning/drug effects , Membrane Potential, Mitochondrial/drug effects , Memory Disorders/metabolism , Memory Disorders/psychology , Mice, Inbred ICR , Neurons/pathology , Neuroprotective Agents/therapeutic use , Peptide Fragments/metabolism , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Rivastigmine/pharmacology , Signal TransductionABSTRACT
Cholinesterase inhibitors are first-line therapy for Alzheimer's disease (AD). DL0410 is an AChE/BuChE dual inhibitor with a novel new structural scaffold. It has been demonstrated that DL0410 could improve memory deficits in both Aß1-42-induced and scopolamine-induced amnesia in mice. In the present study, the therapeutic effect of DL0410 and its action mechanism were investigated in APP/PS1 transgenic mice. Six-month old APP/PS1 transgenic mice were orally administered with DL0410 (3, 10, 30 mg/kg/day). After 60 days, several behavioural tests, including the Morris water maze and step-down tests, were used to investigate the effects of DL0410 on mice behaviours. All the behavioural experimental results showed that DL0410 significantly ameliorated memory deficits. Meanwhile, DL0410 attenuated neural cell damage and reduced senile plaques significantly in the hippocampus of APP/PS1 transgenic mice. In addition, DL0410 significantly decreased Aß plaques, while increasing the number of synapses and the thickness of PSD in the hippocampus. We also found DL0410 decreased the expression of APP, NMDAR1B and the phosphorylation level of NMDAR2B, and increased the phosphorylation level of CAMKII and the expression of PSD-95. In this study, the results of behavioural tests demonstrated for the first time that DL0410 could improve learning and memory dysfunction in APP/PS1 transgenic mice. The mechanism of its beneficial effects might be related to cholinesterase inhibition, Aß plaques inhibition, improvement of synapse loss by regulating of expression of proteins related to synapses. As a result, DL0410 could be considered as a candidate drug for the therapy of AD.
Subject(s)
Amyloid beta-Protein Precursor/genetics , Cognition Disorders/drug therapy , Cognition Disorders/pathology , Plaque, Amyloid/drug therapy , Presenilin-1/genetics , Synapses/drug effects , Synapses/pathology , Acetylcholinesterase/blood , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Amyloid beta-Protein Precursor/biosynthesis , Animals , Behavior, Animal/drug effects , Butyrylcholinesterase/blood , Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Cerebral Cortex/metabolism , Cholinesterase Inhibitors/pharmacology , Cholinesterase Inhibitors/therapeutic use , Disease Models, Animal , Disks Large Homolog 4 Protein , Dose-Response Relationship, Drug , Guanylate Kinases/biosynthesis , Hippocampus/metabolism , Hippocampus/pathology , Hippocampus/ultrastructure , Male , Membrane Proteins/biosynthesis , Mice , Mice, Transgenic , Phosphorylation/drug effects , Plaque, Amyloid/metabolism , Post-Synaptic Density/drug effects , Post-Synaptic Density/ultrastructure , Receptors, N-Methyl-D-Aspartate/biosynthesis , Receptors, N-Methyl-D-Aspartate/metabolismABSTRACT
Baicalein, a flavonoid from Scutellaria baicalensis Georgi, has been shown to possess neuroprotective properties. The purpose of this study was to explore the effects of baicalein on motor behavioral deficits and gene expression in N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mice model of Parkinson's disease (PD). The behavioral results showed that baicalein significantly improves the abnormal behaviors in MPTP-induced mice model of PD, as manifested by shortening the total time for climbing down the pole, prolonging the latent periods of rotarod, and increasing the vertical movements. Using cDNA microarray and subsequent bioinformatic analyses, it was found that baicalein significantly promotes the biological processes including neurogenesis, neuroblast proliferation, neurotrophin signaling pathway, walking and locomotor behaviors, and inhibits dopamine metabolic process through regulation of gene expressions. Based on analysis of gene co-expression networks, the results indicated that the regulation of genes such as LIMK1, SNCA and GLRA1 by baicalein might play central roles in the network. Our results provide experimental evidence for the potential use of baicalein in the treatment of PD, and revealed gene expression profiles, biological processes and pathways influenced by baicalein in MPTP-treated mice.
