APP/PS1小鼠中PEG-PLA纳米粒的表面蛋白冠组成及其脑内递送的实验研究

摘要 目的：研究阿尔茨海默病（Alzhemer''s disease,AD）模型鼠中聚乙二醇聚乳酸（poly(ethylene glycol)-poly(l-lactide),PEG-PLA）纳米粒表面蛋白冠组成及其对脑内递送特性的影响。方法：制备PEG-PLA纳米粒,测定纳米粒的zeta电位及粒径,采用透射电子显微镜观察纳米粒形态。通过双光子显微镜观察APP/PS1小鼠与野生型（Wild Type,WT）小鼠脑内PEG-PLA纳米粒分布特性。采用液相色谱-质谱联用（LC-MS）技术对PEG-PLA纳米粒分别与APP/PS1小鼠和WT小鼠血浆孵育形成的两种不同蛋白冠进行蛋白组学分析。结果：制备的PEG-PLA纳米粒粒径均一,分散性较好。静脉注射PEG-PLA后,APP/PS1小鼠脑内纳米粒量明显高于WT小鼠。蛋白质组学结果显示,APP/PS1小鼠血浆孵育组PEG-PLA纳米粒表面蛋白冠中凝聚素（Clusterin）明显高于WT小鼠血浆孵育组,该蛋白与纳米粒逃避机体清除有关。此外,纳米粒蛋白冠中血管性血友病因子（Von Willebrand factor）、玻连蛋白（Vitronectin）、肌球蛋白重链-9（Myosin-9）等参与细胞粘附作用相关蛋白在APP/PS1小鼠血浆孵育组也明显多于WT小鼠血浆孵育组。结论：PEG-PLA纳米粒在AD模型小鼠中表现出的高入脑量,可能与AD疾病影响纳米粒蛋白冠组成有关。     

NAD/NADP及其介导氧化应激在神经退行性疾病中的作用

神经退行性疾病如阿尔茨海默病、帕金森病、亨廷顿病等疾病的发生与氧化应激紧密相关。NAD和NADP是维持氧化系统和抗氧化系统平衡的两个关键物质。NAD和NADP的生物合成和降解有多种途径,参与其生物途径的物质如NAMPT、NADK、PARP1、SIRT1、CD38等,均报道在神经退行性疾病发挥一定的作用。因此,本文分别从NAD和NADP的合成和降解途径中的一些关键物质出发,结合氧化应激总结并探讨它们在神经退行性疾病的作用,以期为临床治疗神经退行性疾病提供新思路。     

乳铁蛋白修饰纳米粒包载的α-倒捻子素对AD模型动物脑内特征性病理改变的影响

目的:采用乳铁蛋白修饰的PEG-PLA纳米粒为递药工具包载α-M,探讨其对快速老化SAMP8小鼠AD相关脑内病理特征的改善作用。方法:用乳化/溶剂蒸发法制备载α-M的PEG-PLA纳米粒NP(α-M),将巯基化的乳铁蛋白连接于纳米粒表面,得到Lf-NP(α-M)。7月龄SAMP8系小鼠尾静脉给予注射生理盐水、Lf-NP(α-M)或空白纳米粒溶液,每日一次,连续两周。正常老化小鼠SAMR为模型对照组,通过对脑组织进行免疫组化分析,观察Lf-NP(α-M)对SAMP8小鼠脑内炎症、Aβ沉积等AD特征性病理变化的影响。结果:0.5、2 mg/kgα-M对SAMP8小鼠脑内小胶质细胞激活、星形胶质细胞增生以及Aβ沉积均无显著影响;0.5mg/kg Lf-NP(α-M)可抑制小胶质细胞的激活(P0.001),2 mg/m L Lf-NP(α-M)显著抑制星形胶质细胞增生以及Aβ沉积(P0.05)。结论:乳铁蛋白修饰的包载α-M的可降解纳米粒脑靶向递药系统成功有效,显著提高α-M的成药性并改善AD模型小鼠脑内特征性病理改变。     

Design,synthesis and evaluation of novel bivalent β-carboline derivatives as multifunctional agents for the treatment of Alzheimer's disease

To develop potent multi-target ligands against Alzheimer's disease (AD), a series of novel bivalent β-carboline derivatives were designed, synthesized, and evaluated. In vitro studies revealed these compounds exhibited good multifunctional activities. In particular, compounds 8f and 8g showed the good selectivity potency on BuChE inhibition (IC₅₀?=?1.7 and 2.7?μM, respectively), Aβ_1-42 disaggregation and neuroprotection. Compared with the positive control resveratrol, 8f and 8g showed better activity in inhibiting Aβ_1-42 aggregation, with inhibitory rate 82.7% and 85.7% at 25?μM, respectively. Moreover, compounds 8e, 8f and 8g displayed excellent neuroprotective activity by ameliorating the impairment induced by H₂O₂, okadaic acid (OA) and Aβ_1-42 without cytotoxicity in SH-SY5Y cells. Thus, the present study evidently showed that compounds 8f and 8g are potent multi-functional agents against AD and might serve as promising lead candidates for further development.     

Glycomics of pediatric and adulthood diseases of the central nervous system

Glycosylation consists in the covalent linkage of a carbohydrate structure to membrane bound and secreted glycoconjugates. It is a common post-translational modification that serves multiple functions in cell differentiation, signaling and intercellular communication. Unlike DNA/RNA/protein, the addition of complex carbohydrates is not-template driven and it is conceivable that both genetics and environmental factors might interact to influence glycosylation machinery in several pathological processes. Over the last few decades, the recognition of Congenital Disorders of Glycosylation (CDG) as an increasing number of genetic diseases of glycosylation with almost constant nervous system involvement, dramatically illustrated the consequences of abnormal glycosylation as improper CNS development and function. In addition, CDG recognition contributed to postulate that aberrant glycosylation processes might play a role in multifactorial, complex CNS diseases. On this context, CNS glycomics explores the effects of possible aberrant glycosylation to identify potential glyco-biomarkers useful for the diagnosis and ultimately for potential intervention strategies in neurological diseases. Up to date, CNS glycomics is an emerging, still uncharted area because of the specificity of CNS glycosylation, the complexity of the neurological disorders and for the inaccessibility and invasiveness of disease relevant samples. Here we review current knowledge on clinical glycomics of nervous system diseases, starting with CDG to include those pediatric and adulthood neuropsychiatric diseases where some evidences suggest that multifactor determinants converge to dysregulate glycosylation. Conventional and mass spectrometry-based high throughput technology for glyco-biomarker detection in CNS diseases is reported.     

ACTIGRAPHIC SLEEP-WAKE PATTERNS AND URINARY 6-SULFATOXYMELATONIN EXCRETION IN PATIENTS WITH ALZHEIMER'S DISEASE

Recent studies suggest melatonin, due to its antioxidant and free-radical- scavenging actions, may play a role in the neuroprotection against amyloid, which is implicated in the pathogenesis of Alzheimer's disease (AD). In this study, we determined urinary 6-sulfatoxymelatonin (aMT6s) excretion together with actigraphic sleep-wake patterns of untreated male patients with AD who lived at home. Results were compared with those obtained from normal age-matched elderly and normal young male subjects. Similar measurements were also performed in another group of patients with AD who were treated with a cholinesterase inhibitor (Donepezil, Aricept). Total 24h aMT6s values were significantly reduced in elderly controls (19.9h ± 5.2 μg/24h), in those with untreated AD (12.7 ± 4.4 μg/24h), and in patients treated for AD (12.4 ± 4.4 μ g/24h) compared with normal young men (32.8 ± 3.1 μ g/24h). A day-night difference in aMT6s was evident in all young controls, in 50% of elderly controls, in only 20% of patients with untreated AD, and in 67% of those with AD receiving Aricept. Sleep quality (expressed as sleep efficiency, wake time, and long undisturbed sleep duration) was better in young and elderly controls compared with the two groups of patients with AD. There was no significant correlation between aMT6s values or sleep patterns and the severity of cognitive impairment in patients with AD. Taken together, these data suggest that disrupted sleep, decreased melatonin production, and partial lack of day-night difference in melatonin secretion were observed equally in normal elderly and in patients with AD. Our results do not permit drawing any conclusion as to whether changes in urinary aMT6s excretion is correlated with disturbed sleep in patients with AD. (Chronobiology International, 18(3), 513–524, 2001)     

Zebrafish as a tool in Alzheimer's disease research

Alzheimer's disease is the most prevalent form of neurodegenerative disease. Despite many years of intensive research our understanding of the molecular events leading to this pathology is far from complete. No effective treatments have been defined and questions surround the validity and utility of existing animal models. The zebrafish (and, in particular, its embryos) is a malleable and accessible model possessing a vertebrate neural structure and genome. Zebrafish genes orthologous to those mutated in human familial Alzheimer's disease have been defined. Work in zebrafish has permitted discovery of unique characteristics of these genes that would have been difficult to observe with other models. In this brief review we give an overview of Alzheimer's disease and transgenic animal models before examining the current contribution of zebrafish to this research area. This article is part of a Special Issue entitled Zebrafish Models of Neurological Diseases.     

Protein interaction network for Alzheimer's disease using computational approach

Alzheimer''s disease (AD) is the most common form of dementia. It is the sixth leading cause of death in old age people. Despiterecent advances in the field of drug design, the medical treatment for the disease is purely symptomatic and hardly effective. Thusthere is a need to understand the molecular mechanism behind the disease in order to improve the drug aspects of the disease. Weprovided two contributions in the field of proteomics in drug design. First, we have constructed a protein-protein interactionnetwork for Alzheimer''s disease reviewed proteins with 1412 interactions predicted among 969 proteins. Second, the diseaseproteins were given confidence scores to prioritize and then analyzed for their homology nature with respect to paralogs andhomologs. The homology persisted with the mouse giving a basis for drug design phase. The method will create a new drug designtechnique in the field of bioinformatics by linking drug design process with protein-protein interactions via signal pathways. Thismethod can be improvised for other diseases in future.     

Regulation of autophagy by polyphenols: Paving the road for treatment of neurodegeneration

In the present paper, we will discuss on the importance of autophagy in the central nervous system, and outline the relation between autophagic pathways and the pathogenesis of neurodegenerative disorders. The potential therapeutic benefits of naturally occurring phytochemicals as pharmacological modulators of autophagy will also be addressed. Our findings provide renewed insight on the molecular modes of protection by polyphenols, which is likely to be at least in part mediated not only by their potent antioxidant and anti-inflammatory effects, but also through modulation of autophagic processes to remove the aberrant protein aggregates.