Root-Securing and Brain-Fortifying Liquid Upregulates Caveolin-1 in Cell Model with Alzheimer's Disease through Inhibiting Tau Phosphorylation.

Depei Yuan,Ziyang Shu,Yaoqian Zhu,Chuhua Zeng,Fengjie Wang,Lin Yuan,Qianfeng Chen,Ning Chen

doi:10.1155/2017/6248351

Abstract

In order to explore the effect of root-securing and brain-fortifying Liquid- (RSBFL-) mediated caveolin-1 (CAV-1) on phosphorylation of Tau protein and to uncover underlying mechanisms of RSBFL for the prevention and treatment of Alzheimer's disease (AD), hippocampal neurons isolated from neonatal SD rats and cultured in DMEM-F12 medium were induced by exogenous Aβ1–42 to establish a cell model with AD. Meanwhile, pEGFP-C1-CAV1 and CAV1-shRNA plasmids were transfected into hippocampal neurons for CAV-1 overexpression and silence, respectively. The serum containing RSBFL was prepared for the intervention of AD model cells. The expression of CAV-1, GSK-3β, and p-Tau in normal hippocampal neurons and AD model cells in the presence of serum containing RSBFL was evaluated. The model hippocampal neurons with AD induced by Aβ1–42 revealed an obvious CAV-1 inhibition, enhanced GSK-3β activity, and abnormal Tau phosphorylation. In contrast, the treatment with serum containing RSBFL could upregulate CAV-1 in AD hippocampal neurons (P < 0.05) with improved p-GSK-3βSer9 and reduced p-GSK-3βTyr216 (P < 0.01), as well as suppressed abnormal phosphorylation of Tau protein. Therefore, RSBFL has an excellent protective effect on hippocampal neurons through increasing CAV-1 expression, inhibiting GSK-3β activity, and reducing excessive abnormal phosphorylation of Tau protein.

Highlights

Alzheimer’s disease (AD) is a progressive degenerative disease of central nervous system and has two major characteristics including the formation of neurofibrillary tangles (NFTs) from the aggregates of excessively phosphorylated Tau protein in neurons [1] and the formation of senile plaques (SPs) from the aggregates of β-amyloid (Aβ) outside neurons
After transfecting recombinant pEGFP-C1-CAV1 plasmid in hippocampal neurons, the transfection at the ratio of 5 μL plasmid to 7.5 μL liposome could result in the strongest fluorescence intensity in transfected cells at the largest population (Figure 1(b1)), which was followed by the ratios of 2.5 μL plasmid to 3.75 μL liposome (Figure 1(a1)) and 7.5 μL plasmid to 11.25 μL liposome, as shown in the weakest fluorescence intensity and large amount of cell death (Figure 1(c1))
The serum containing SRBFL could rescue the expression of CAV-1 (a) in the presence of CAV1-shRNA and cause the reduced and enhanced phosphorylation of glycogen synthase kinase-3β (GSK-3β) at the sites of Ser9 and Tyr216, respectively, as well as leading to the increased phosphorylation of Tau at the sites of Thr231 and Ser396. These results indicated that Root-securing and brain-fortifying liquid (RSBFL) could promote the expression of CAV-1, inhibit the activity of GSK-3β, and reduce the phosphorylation of Tau

Summary

Introduction

Alzheimer’s disease (AD) is a progressive degenerative disease of central nervous system and has two major characteristics including the formation of neurofibrillary tangles (NFTs) from the aggregates of excessively phosphorylated Tau protein in neurons [1] and the formation of senile plaques (SPs) from the aggregates of β-amyloid (Aβ) outside neurons. Excessive abnormal phosphorylation of Tau is mainly regulated by glycogen synthase kinase-3β (GSK-3β), Cdk, MAPK, and other protein kinases. GSK-3β reveals the highest affinity and the strongest phosphorylation for Tau protein. A number of studies confirm that the activation of GSK-3β can obviously promote the phosphorylation of Tau [3, 4]. The underlying mechanisms of Chinese herbs for the prevention and treatment of AD are still unclear. GSK-3β could be considered as the target to explore the possible mechanisms of AD during the application of traditional Chinese medicine

Methods

Results

Conclusion