Non-steroidal anti-inflammatory drugs in Parkinson's disease

Parkinson's disease (PD) is known to be a chronic and progressive neurodegenerative disease caused by a selective degeneration of dopaminergic (DAergic) neurons in the substantia nigra pars compacta (SNc). A large body of experimental evidence indicates that the factors involved in the pathogenesis of this disease are several, occurring inside and outside the DAergic neuron. Recently, the role of the neuron-glia interaction and the inflammatory process, in particular, has been the object of intense study by the research community. It seems to represent a new therapeutic approach opportunity for this neurological disorder. Indeed, it has been demonstrated that the cyclooxygenase type 2 (COX-2) is up-regulated in SNc DAergic neurons in both PD patients and animal models of PD and, furthermore, non-steroidal anti-inflammatory drugs (NSAIDs) pre-treatment protects against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or 6 hydroxydopamine (6-OHDA)-induced nigro-striatal dopamine degeneration. Moreover, recent epidemiological studies have revealed that the risk of developing PD is reduced in humans who make therapeutical use of NSAIDs. Consequently, it is hypothesized that they might delay or prevent the onset of PD. However, whether or not these common drugs may also be of benefit to those individuals who already have Parkinson's disease has not as yet been shown. In this paper, evidence relating to the protective effects of aspirin or other NSAIDs on DAergic neurons in animal models of Parkinson's disease will be discussed. In addition, the pharmacological mechanisms by which these molecules can exert their neuroprotective effects will be reviewed. Finally, epidemiological data exploring the effectiveness of NSAIDs in the prevention of PD and their possible use as adjuvants in the therapy of this neurodegenerative disease will also be examined.     

β-淀粉样蛋白和载脂蛋白E4降低神经元膜流动性

为了研究 Aβ和 Apo E对神经元膜流动性的影响 ,探索 Aβ和 Apo E的神经毒性机制 ,制备急性分离的新生 SD大鼠海马和皮质神经元细胞悬液 ,采用显微准弹性激光散射技术 ,分析单个神经元散射光强度的自相关函数 (ACF) ,通过公式由 ACF拟合出反映细胞膜流动性的频移线宽 Γ。结果发现 Aβ2 5～ 3 5和 Apo E4作用 5min和 3 5min后均降低海马和皮质神经元 ACF的衰减速率及频移线宽 Γ,而 Apo E3对两者无影响 ,提示 Aβ和 Apo E4均可降低神经元膜流动性。     

炎症反应及抗炎药物与阿尔茨海默病的研究进展

阿尔茨海默病(Alzheimer's disease,AD)又称老年性痴呆,是一种常见的以认知功能进行性减退为特征的中枢神经系统(CNS)变性疾病,其病因和发病机制十分复杂,迄今仍未完全阐明.近年来越来越多的实验和临床证据表明,AD、帕金森病和多发性硬化等CNS疾病均与炎症反应有关,而对AD的研究表明:大量已知的炎症因子参与了AD的炎症损伤病理过程,在老年斑周围有大量活化的胶质细胞和炎症细胞,AD患者脑内持续存在慢性炎症反应等,这证明炎症机制参与了AD病理的发生发展过程.     

Aspirin,anti-inflammatory drugs and risk of dementia

Objective. To test the hypothesis that aspirin and non-steroidal anti-inflammatory drugs (NSAIDs) may prevent dementia or cognitive impairment. Design. A two-wave longitudinal study over 3.6 years. Setting. A community survey of elderly persons living in Canberra, Australia. Participants. There were 1045 elderly persons aged 70 at the start of the study; cognitive assessment was obtained at both waves on 588. Main outcome measures. Cognitive functioning was measured using the Mini-Mental State Examination, an episodic memory test, a test of mental speed and the National Adult Reading Test. Dementia was assessed using the Canberra Interview for the Elderly. Results. On cross-sectional data, those who had been taking NSAIDs or aspirin performed no better on the cognitive tests after account had been taken of other confounding variables. There was no interaction with apolipoprotein E genotype. On longitudinal data, no difference was found between NSAID or aspirin users and controls, either in cognitive decline or incidence of dementia. Conclusions. The results do not support the hypothesis that aspirin or NSAIDs have a protective effect, but it remains possible that various sources of measurement error may have attenuated an effect of clinical significance from either type of drug. Conclusive evidence can be obtained only by a prospective trial. © 1997 John Wiley & Sons, Ltd.     

Immobilized amyloid precursor protein constructs: a tool for the in vitro screening of glial cell reactivity

Astrocytes and microglia are closely associated with amyloid plaques in Alzheimer's disease (AD). Microglia constitute the first barrier surrounding plaques, although they seem to be unable to remove them efficiently. We evaluated the reaction of microglial cells from neonatal rats and mice to plaque mimetics. The C-terminal part of the amyloid precursor protein (APP) or amyloid peptide (A beta) was immobilized to either 60-microm or 2.8-microm beads and incubated with microglial cells. Beads of 60 microm, having approximately the size of senile plaques, were not phagocytosed, in contrast to 2.8-microm beads, which were phagocytosed by microglia but not by astrocytes. Once taken up by the cells, proteins immobilized to the beads were degraded rapidly, as confirmed by mass spectrometry and immunofluorescence with an antibody against beta-amyloid. On the other hand, no protein degradation was observed with 60-microm beads. Also, probably as a reaction to its incapability to phagocytose the beads, glia organized around the beads and started to proliferate. Cell proliferation was more pronounced when the beads contained the A beta epitope compared with the beads with an inert surface. This in vitro effect could be exploited to set up a screening assay for compounds that ameliorate the adverse reaction of microglia supposed to contribute to the pathogenesis of AD.     

No effect of apolipoprotein E on neuronal cell death due to excitotoxic and apoptotic agents in vitro and neonatal hypoxic ischaemia in vivo

The epsilon4 allele of apolipoprotein E (apoE) is a genetic risk factor for Alzheimer's disease. Studies also suggest that the epsilon4 allele may be a risk factor for poor outcome following head trauma, brain haemorrhage and ischaemia. The mechanism by which the presence of an apoE epsilon4 allele and certain brain injuries act to predispose to Alzheimer's disease and poor outcome following brain injury is unknown. We questioned whether poor outcome after brain injury was due to direct modification by apoE protein and its gene variants of susceptibility to glutamate-mediated excitotoxic injury and apoptosis, mechanisms of cell death which occur following ischaemia and trauma. We investigated the effect of the presence or absence of endogenous murine apoE protein and different apoE isoforms in modification of the survival of murine embryonic cortical neurons exposed to the glutamate agonist, N-methyl-D-aspartic acid (NMDA) or apoptotic insult by staurosporine, and on the amount of brain injury sustained following a hypoxic-ischaemic insult in vivo to the brain of neonatal mice transgenically expressing human apoE epsilon3 or epsilon4. Our data provide evidence that apoE does not appear to alter neuronal viability following diverse types of acute neuronal insult, e.g. hypoxic-ischaemic or acute exposure to injurious agents in the models we have examined. This suggests that if apoE does modify the extent of brain damage and recovery after injury, it seems unlikely to be a result of direct or indirect modulation of excitotoxic or apoptotic cell death.     

Parkinson病与Alzheimer病载脂蛋白E基因型分布的研究

目的探讨载脂蛋RE（apoE）基因多态性与Parkinson病及Alzheimer病的关系。方法应用聚合酶链反应-限制性片段氏度多态性（PCR－RFLP）技术检测72名帕金森氏病（PD）、68名Alzheimer病（AD）患者和66名正常老年人的apoE基因型分布。结果PD组apoE2、apoE3、apoE4及AD组apoE4等位基因频率与对照组比较无统计学意义（P＞0.05）;AD组apoE2等位基因频率明显低于对照组（P＜0．01）。结论apoE基因型分布与PD发病无关;与AD发病相关,即apoE2基因可能具有防止AD发病的作用;不支持apoE4是中国人散发性AD发病病危因素的结论。     

Polymorphisms in the apolipoprotein E (APOE) gene in gerontopsychiatric patients

Two recently described polymorphisms in the promoter region of the apolipoprotein E (APOE), the −491A7T and Th1/E47csT/G polymorphism, have been suggested to be associated with an increased risk for Alzheimer's disease (AD) independent from the APOE ɛ4 carrier status. We studied the association between the APOE ɛ4 polymorphism and the −491A/T and Th1E47csT/G polymorphisms in a sample of 118 healthy, non-demented controls and 239 consecutively recruited gerontopsychiatric patients diagnosed as: Alzheimer's disease (N = 89), age mild cognitive impairment (N = 32), memory complainers without any congitive deficit (N = 54) and depression/other psychiatric disorders (N = 64), to test whether the investigated polymorphisms have a high enough selectivity and specificity to distinguish between the different gerontopsychiatric disorders to differentiate AD genetically from other forms of dementia, respectively. Also a possible association with the APOE ɛ4 polymorphism was examined. We found a statistically significant association between the APOE ɛ4 allele and Alzheimer's disease (p = 0.0001) and age associated memory impairment (p = 0.006). Our study failed to show an association between the promoter polymorphisms −491A/T and Th1E47csT/G in the APOE gene and gerontopsychiatric disorders either alone or in relationship to the APOE ɛ4 polymorphism. However, if we combine our results with three previous published positive reports there seems to be an association between the −491A/T polymorphism and AD, though its size is less than found in the original publication. Accepted: 3 February 2001     

Nonsteroidal anti-inflammatory drugs and risk of Parkinson's disease.

Inflammation and oxidative stress have been implicated as pathogenic mechanisms in Parkinson's disease (PD). Evidence from in vitro and animal studies suggests a possible protective role of nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin. We investigated the risk of PD associated with use of aspirin and nonaspirin NSAIDs in a population-based case-control study among enrollees of Group Health Cooperative, a health maintenance organization in the Seattle area. Subjects included 206 cases between ages 35 and 89 with a new diagnosis of idiopathic PD between 1992 and 2002, and 383 randomly selected controls frequency-matched by age, sex, duration of enrollment, and clinic. We obtained information on participants' age, smoking, and medical history from interview. Exposure to NSAIDs was ascertained from an automated pharmacy database. Medications filled within 5 years of the interview were excluded. After adjusting for age, sex, smoking, duration of enrollment, and clinic, the risk of PD among individuals who received nonaspirin NSAIDs between 1977 and 1992 was 0.90 (95% CI: 0.59-1.35) and 1.67 (95% CI: 0.60-4.60) between 1993 and 2002. Use of ibuprofen was not associated with PD (OR: 0.89; 95% CI: 0.60-1.32). The risk of PD associated with aspirin or aspirin-containing medications was 0.74 (95% CI: 0.49-1.12). We observed no trend in risk according to number of fills for these drugs. Our results provide only limited support for the hypothesis that use of aspirin may reduce the risk of this disease, and no indication of protection from other NSAIDs.     

Alzheimer病早期脑脊液tau蛋白与ApoE基因的关系

目的探讨Alzheimer病患者脑脊液tau蛋白与ApoE基因型的关系。方法对84例患者脑脊液微管相关蛋白(tau蛋白)应用ELISA法对进行定量,其中41例临床诊断为早期Alzheimer病(AD),23例伴其他类型的痴呆,6例为Down综合征患者;14例非痴呆患者为对照组。结果多变量ANOVA分析显示痴呆患者与ApoE等位基因者脑脊液tau蛋白升高,AD患者脑脊液tau蛋白浓度明显高于对照组。而非AD痴呆患者脑脊液tau蛋白浓度与AD患者和对照组无明显差异,伴ApoEε4等位基因的AD病人与不伴ε4等位基因的AD病人相比,tau蛋白浓度升高。结论脑脊液tau蛋白浓度升高提示携带ε4等位基因AD病人早期发生神经变性和神经纤维病理学改变,应用ELISA法检测脑脊液tau蛋白对诊断早期AD及与其他类型的痴呆相鉴别缺乏敏感性和特异性,应首先考虑ApoE基因类型。     

Activity of flurbiprofen and chemically related anti-inflammatory drugs in models of Alzheimer's disease

Currently, there is an intense debate on the potential use of nonsteroidal anti-inflammatory drugs (NSAIDs) in Alzheimer's disease (AD). NSAIDs are among the most widely prescribed drugs for the treatment of pain, fever, and inflammation. Their effects are largely attributed to the inhibition of the enzymatic activity of cyclooxygenase (COX)-1 and -2. The apparent activity of this class of drugs stems from one critical pathological process underlying AD and other neurodegenerative disorders, i.e., the presence of chronic neuroinflammation. In fact, prolonged use of NSAIDs is associated with reduced risk of AD. Besides COX inhibition, additional mechanisms could contribute to the potential activity of NSAIDs in AD. For example, several studies show that only a few selected NSAIDs also affect β-amyloid (Aβ) deposition and metabolism. Among the Aβ-effective NSAIDs, flurbiprofen raised particular interest because of its multiple actions on key AD hallmarks. Studies in cell lines and animal models have shown that flurbiprofen racemate, its R-enantiomer and its nitric oxide (NO)-releasing derivatives, HCT 1026 and NCX 2216, are effective on AD amyloid pathology. Moreover, HCT 1026 and NCX 2216 differentially influence the cellular component of neuroinflammation (i.e., microglia activation) in some experimental settings, i.e., HCT 1026 inhibits the activation of microglia, while NCX 2216 can either enhance or inhibit microglial activation, depending upon the experimental conditions. It is still unclear which effects on microglia will prove most beneficial. Ultimately, clinical studies in AD patients will provide the best information as to whether selected NSAIDs will improve this devastating disease.     

Acetylcholinesterase induces the expression of the beta-amyloid precursor protein in glia and activates glial cells in culture

Acetylcholinesterase (AChE) activities in CNS physiopathology are increasingly diverse and range from neuritogenesis, through synaptogenesis, to enhancement of amyloid fiber assembly. In Alzheimer's disease, senile plaques and neurodegeneration specially affect regions enriched for cholinergic synapses. In this study we show an effect of AChE that could contribute to the increased deposition of Abeta in certain regions. Affinity-purified AChE induced the expression of amyloid-beta-precursor protein (beta-APP) in glial cells in a concentration-dependent manner up to 5 nM. In glia, AChE also increased inducible nitric oxide synthase (iNOS) assessed by immunocytochemistry and decreased reductive metabolism as evidence of cell activation. AChE could increase the expression of beta-APP in astrocytes and microglia as result of the activation of glial cells. As a whole, we found that AChE has additional effects that could result in an increased synthesis of Abeta, both by increasing beta-APP expression of astrocytes and by further activating glial cells.     

Relation of apolipoprotein E polymorphism to clinically diagnosed Alzheimer's disease in the Korean population

The gene for human apolipoprotein E (APOE) is found on the long arm of chromosome 19 (19q13.2) and exists in three common allelic forms, epsilon2, epsilon3, and epsilon4. The APOE epsilon4 allele is overrepresented in Alzheimer's disease (AD) and is accepted as a genetic risk factor. Some studies reported a protective effect of the APOE epsilon2 allele for AD. However, there are some ethnic variations in the proportion of different APOE alleles and their relationship to AD. We examine the distribution of APOE alleles from 30 AD patients and 158 controls in Korea. The control subjects were all cognitively intact unrelated Koreans. The frequencies of APOE alleles in AD patients were 18.3% (epsilon2), 58.3% (epsilon3), and 23.3% (epsilon4). The corresponding frequencies in controls were 13.3% (epsilon2), 72.5% (epsilon3), and 14.2% (epsilon4). The frequency of the APOE epsilon2 allele in AD patients was not significantly different from that in controls. When statistical analysis was conducted after the exclusion of the APOE epsilon2 allele, the frequency of the APOE epsilon4 allele in AD patients was significantly higher than that in controls (P < 0.05). These results support that the APOE epsilon4 allele plays a role as a risk factor for AD in Koreans and suggest that the APOE epsilon2 allele may not play a protective role in the development of AD in Koreans.     

Apolipoprotein E4 (ApoE4) but not ApoE3 or ApoE2 potentiates β-amyloid protein activation of complement in vitro

Apolipoprotein E4 (ApoE4) increases the risk of late-onset Alzheimer's disease (AD). It binds tightly to β-amyloid protein (A β), which is known to activate the classical complement pathway in vitro. Since complement activation is a possible mechanism for promoting inflammation in AD, we tested, utilizing ELISA techniques, whether the various isoforms of ApoE could influence A β complement activation, or could themselves activate the pathway. A β applied alone to ELISA plate wells at concentrations of 100–500 ng showed a linear increase in ability to activate serum complement, but all the ApoE isoproteins were inactive. When 200 or 430 ng of A β were plated and then exposed to solutions of 100–200 ng of ApoE2, ApoE3, ApoE4 or bovine serum albumin (BSA), only ApoE4 significantly enhanced the activation. This ApoE4-specific enhancement of complement activation by A β may relate to its role in increasing the risk of late-onset AD.     

Increased neuronal and glial expression of protein kinase C isoforms in neocortex of transgenic Tg2576 mice with amyloid pathology

We investigated the influence of five- to sevenfold neuronal overexpression of the Swedish mutation of human APP695 (APPsw) in the transgenic mouse strain Tg2576 on neocortical protein kinase C (PKC) expression and subcellular distribution. Using specific antibodies to PKC alpha, PKC beta, PKC gamma, PKC epsilon and PKC zeta isoforms for Western blot analysis, we observed increased immunoreactivity for PKC alpha and PKC gamma isoforms in crude tissue homogenates from the neocortex of 16-month-old APPsw mice as compared with nontransgenic littermates, which was not present in 6 month-old Tg2576 mice. We also observed elevated levels of PKC alpha, PKC beta, PKC gamma and PKC zeta in membrane fractions and reduced concentrations of PKC alpha and PKC gamma in cytosolic fractions of aged Tg2576 mice, indicating that these PKC isoforms are in their activated state. In young, 6-month-old Tg2576 mice, however, the increase in membrane-bound PKC isoforms and concomitant decrease in cytosolic PKC isoforms was much less pronounced, demonstrating the age-dependent nature of alterations in PKC isoforms. Immunocytochemistry of brain sections supported these findings and revealed increased neuronal labelling for PKC alpha, PKC gamma and PKC lambda isoforms in neocortex of 16-month-old APPsw mice compared with nontransgenic littermates, with the increase being strongest for PKC gamma and PKC lambda isoforms. Additionally, PKC gamma and to a lesser extent PKC lambda isoforms were induced in reactive astrocytes in proximity to amyloid plaques. Our data indicate that neuronal overexpression of APPsw causes a dynamic change in neuronal expression and activation of multiple PKC isoforms known to be regulators of proteolytic amyloid precursor protein (APP) processing (PKC alpha) and of neuronal survival (PKC lambda and PKC zeta). The induction of the PKC gamma and PKC lambda isoforms in reactive astrocytes surrounding amyloid plaques might be required for astrocyte activation and astrocytic cytokine expression in response to amyloid plaque formation.     

8-羟基鸟嘌呤糖苷酶1、载脂蛋白酶E基因多态性与阿尔茨海默病相关性研究

目的 探讨河南汉族人群8-羟基鸟嘌呤糖苷酶1(OGG1)、载脂蛋白酶E(ApoE)基因多态性与阿尔茨海默病的相关性.方法 采用聚合酶链反应(PCR)及基因测序检测126例正常对照组和58例阿尔茨海默病患者OGG1基因第326位Ser/Ser、Ser/Cys、Cys/Cys基因型多态分布及ApoE e2、e3、ε4基因型多态分布.结果 与对照组比较,AD组OGG1基因的3种基因型分布总体差异有统计学意义(x2＝6.337,P＝0.042),G等位基因频率高于健康对照组(χ2＝ 6.447,P＝0.011);AD组ApoE等位基因ε4频率显著升高,呈正关联(χ2＝ 11.722,OR＝2.872,95％CI＝ 1.542 ～5.351,P＝0.001).ApoEε4等位基因不影响OGG1基因型或等位基因的分布频率(P＞0.05).经年龄分层后,AD组OGG1基因分布无差异性(P＞0.05),ApoE基因在大于70岁组分布有差异性(x2＝14.163,P＝0.001).结论 河南汉族人群中,OGG1 G等位基因可能是AD发病的独立于ApoE之外的危险因素,与年龄无相关性;ApoEε4等位基因是散发性AD的主要危险因素,并与年龄有相关性,ε3等位基因是AD的保护因素.     

Relationship between apolipoprotein E and the amyloid deposits and dystrophic neurites of Alzheimer's disease

T. C. Dickson, H. L. Saunders and J. C. Vickers (1997) Neuropathology and Applied Neurobiology , 23, 483–491
Relationship between apolipoprotein E and the amyloid deposits and dystrophic neurites of Alzheimer's disease
Although the inheritance of certain apolipoprotein E (ApoE) alleles has been recognized as a genetic risk factor for Alzheimer's disease, the role of ApoE in the pathology underlying this disease is unclear. Several reports have emphasized the association of ApoE with either β-amyloid plaque formation or the development of neurofibrillary pathology. Utilization of multiple label immunohistochemical methods enabled us to examine directly the localization of ApoE immunoreactivity relative to β- amyloid plaques, dystrophic neurites and neurofibrillary tangles. In Alzheimer's disease cases, β-amyloid plaques showing high ApoE immunoreactivity were localized to layers II, III and V of the neocortex. In layer I, β-amyloid plaques were unlabelled for ApoE relative to β-amyloid. Dense core plaques labelled for β-amyloid often had only the central portions labelled for ApoE. Conversely, ApoE labelled spherical structures within some plaques were not immunoreactive for β-amyloid or dystrophic neurite markers. Unlike β-amyloid labelled plaques, all ApoE immunoreactive plaques were associated with dystrophic neurites. In preclinical Alzheimer's disease cases, most plaques were double labelled for β-amyloid and ApoE. ApoE did not label dystrophic neurites or the early stages of neurofibrillary tangle formation, indicating that ApoE may not be directly involved in neurofibrillary pathology. The specific presence of ApoE in plaques associated with dystrophic neurites in demented patients suggests that ApoE may contribute toward a higher degree of β- amyloid fibrillogenesis, enhancing the ability of certain plaques to cause damage to surrounding axons.     

Does apolipoprotein E (Apo-E) genotype influence nicotinic receptor binding in Alzheimer's disease

Summary. We wished to determine the influence of the apolipoprotein E (Apo-E) genotype on the loss of high affinity nicotinic acetylcholine receptor (nAChR) binding in Alzheimer's disease (AD). The interaction between ε4 allele gene dose and cholinergic loss in AD remains controversial. We have demonstrated that nicotinic binding is significantly lost in AD. Tissue from the midfrontal (MF) cortex of 7 subjects with no ε4 allele copies (ε−/ε−) (mean death age 75.1 ± 10.4 years) was compared to MF cortex of 14 subjects heterozygous for the ε4 allele (ε4/ε−) (mean death age 81.4 ± 7.3 years) and MF cortex of 10 subjects homozygous for the ε4 allele (ε4/ε4) (mean death age 79.6 ± 5.0 years). All subjects were autopsy confirmed AD (using NIA and CERAD criteria) and met NINCDS-ADRDA clinical criteria for probable or possible AD. Nicotine AChR binding was assayed using the high affinity nicotinic agonist ³H-epibatidine ([³H]-Epi). Apo-E genotype was determined in blood samples or in post-mortem tissue. The mean age at death was not significantly different among the groups (p = 0.19). There was no difference in mean [³H]-Epi total binding among the three groups (6.7 ± 4.6, 6.1 ± 2.4, and 6.0 ± 1.0 fmol/mg protein for ε−/ε−, ε4/ε−, and ε4/ε4 respectively. We conclude that the presence or absence of the Apo-E4 genotype does not influence the loss of high affinity nAChR in AD. Received January 16, 2001; accepted April 16, 2001     

Transient expression of glial fibrillary acidic protein in developing oligodendrocytes in vitro

Expression of galactocerebroside (GC) and glial fibrillary acidic protein (GFAP) was studied in oligodendrocyte-enriched cultures of newborn mouse brains. In the cultures, GC was detectable as early as 1 day in vitro (1-DIV). Using double immunofluorescence labeling, some GC-positive cells were also stained homogeneously by the anti-GFAP serum. The intensity of GFAP staining increased until 9-DIV when the GC-positive cells revealed the typical morphology of oligodendrocytes, and the GFAP staining faded thereafter. The GFAP staining pattern of the GC-positive cells was not changed upon exposure to demecolcine, even though the GC-negative, GFAP-positive astrocytes showed perinuclear aggregation of GFAP. No intermediate filaments were observed in the oligodendrocytes by electron microscopy. The results suggest that the oligodendrocytes may have soluble GFAP in a certain period of early development.