Vitamin E protects against Alzheimer's amyloid peptide (25–35)-induced changes in neocortical synaptosomal membrane lipid structure and composition

Koppal, Tanuja; Subramaniam, Ram; Drake, Jennifer; Prasad, M. R. N.; Dhillon, Harbhajan S.; Butterfield, D. Allan

doi:10.1016/s0006-8993(97)01466-2

Cited by 71 publications

(38 citation statements)

References 20 publications

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“…In support of this suggestion, A␤-induced increases in Ca 2ϩ influx are reported to be involved in mediating the apoptotic effects of A␤ in PC12 cells (19,20), and L-type VDCCs have been demonstrated to mediate A␤-induced neurotoxicity in cultured hippocampal neurons (21). In addition, mobilization of intracellular Ca 2ϩ stores via formation of reactive oxygen species has been suggested to underlie the detrimental effects of A␤-(25-35) on synaptosomal membrane lipid structure and composition (22). Although elevation in [Ca 2ϩ ] i has been demonstrated to underlie A␤-induced neuronal apoptosis, A␤ also stimulates glia to produce growth factors that contribute to plaque development (5) and may influence neuronal viability (23).…”

Section: A␤-(1-40) Increasesmentioning

confidence: 99%

Enhancement of 45Ca2+ Influx and Voltage-dependent Ca2+ Channel Activity by β-Amyloid-(1–40) in Rat Cortical Synaptosomes and Cultured Cortical Neurons

MacManus

Ramsden

Murray

et al. 2000

Journal of Biological Chemistry

124

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␤-Amyloid protein is thought to underlie the neurodegeneration associated with Alzheimer's disease by inducing Ca 2؉ -dependent apoptosis. Elevated neuronal expression of the proinflammatory cytokine interleukin-1␤ is an additional feature of neurodegeneration, and in this study we demonstrate that interleukin-1␤ modulates the effects of ␤-amyloid on Ca 2؉ homeostasis in the rat cortex. ␤-Amyloid-(1-40) (1 M) caused a significant increase in 45 Ca 2؉ influx into rat cortical synaptosomes via activation of L-and N-type voltage-dependent Ca 2؉ channels and also increased the amplitude of N-and P-type Ca 2؉ channel currents recorded from cultured cortical neurons. In contrast, interleukin-1␤ (5 ng/ml) reduced the 45 Ca 2؉ influx into cortical synaptosomes and inhibited Ca 2؉ channel activity in cultured cortical neurons. Furthermore, the stimulatory effects of ␤-amyloid protein on Ca 2؉ influx were blocked following exposure to interleukin-1␤, suggesting that interleukin-1␤ may govern neuronal responses to ␤-amyloid by regulating Ca 2؉ homeostasis.␤-Amyloid (A␤-(1-40)) 1 is a peptide fragment derived from proteolytic processing of ␤-amyloid precursor protein (␤APP) (1), which accumulates as an insoluble extracellular deposit around neurons, giving rise to the senile plaques associated with Alzheimer's disease (AD) (2). Increased neuronal expression of the proinflammatory cytokine interleukin-1␤ (IL-1␤) is an additional neuropathological hallmark of AD (3), and inflammatory mediators such as IL-1␤ have been proposed to contribute to the development of amyloid plaques (4). Several reports describe an interaction between IL-1␤ and A␤ at the processing level; IL-1-immunoreactive microglia are prominent components of amyloid plaques in AD (4), and ␤-amyloid promotes release of IL-1␤ by the glial cells that surround senile plaques (5). In turn, IL-1␤ increases ␤APP mRNA expression (6) and promotes processing of ␤APP to liberate A␤ peptide fragments (7). Thus a chain of events involving IL-1␤ and A␤ is involved in plaque formation; however, the nature of the interaction between IL-1␤ and A␤ at a physiological level is poorly understood. Neuronal apoptosis is the suspected causative factor of neurodegeneration in AD, and A␤ fragments have been shown to promote apoptosis in vitro in human-derived neurotypic cells (8) and cultured neurons (9). The mechanism underlying A␤-induced apoptosis is thought to involve disregulation of Ca 2ϩ homeostasis (10). In the C6 glial cell line, expression of the Ca 2ϩ -binding protein calbindin was found to suppress A␤-induced apoptosis (11), providing evidence for the involvement of Ca 2ϩ fluxes in A␤-induced apoptosis. In this study we report that A␤-(1-40) (i) promotes a stimulation of 45 Ca 2ϩ influx into cortical synaptosomes via activation of L-and N-type voltagedependent Ca 2ϩ channels (VDCCs) and (ii) increases the amplitude of N-and P-type VDCC current in cultured cortical neurons. Furthermore, the A␤-(1-40)-induced increase in Ca 2ϩ influx is blocked by the proinflammatory mediato...

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Section: A␤-(1-40) Increasesmentioning

confidence: 99%

Enhancement of 45Ca2+ Influx and Voltage-dependent Ca2+ Channel Activity by β-Amyloid-(1–40) in Rat Cortical Synaptosomes and Cultured Cortical Neurons

MacManus

Ramsden

Murray

et al. 2000

Journal of Biological Chemistry

124

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“…There is evidence relating the etiopathology of AD with free radicals in AD brain patients (21)(22)(23)(24) as well as in in vitro experiments, which suggest that A␤ neurotoxicity operates by an oxidative mechanism (25)(26)(27). Evidence suggests that H 2 O 2 at a high concentration produces toxic reactions; however, at a moderate concentration, H 2 O 2 may functions as a second messenger mediating a variety of signal transduction pathways (28), including tyrosine phosphatase 1B, Jun N-terminal kinase, protein kinase C, and transcription factors like AP-1 and NF-B (29).…”

mentioning

confidence: 99%

Peroxisomal Proliferation Protects from β-Amyloid Neurodegeneration

Santos

Quintanilla²,

Toro

et al. 2005

Journal of Biological Chemistry

140

114

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Alzheimer disease is a neurodegenerative process that leads to severe cognitive impairment as a consequence of selective death of neuronal populations. The molecular pathogenesis of Alzheimer disease involves the participation of the ␤-amyloid peptide (A␤) and oxidative stress. We report here that peroxisomal proliferation attenuated A␤-dependent toxicity in hippocampal neurons. Pretreatment with Wy-14.463 (Wy), a peroxisome proliferator, prevent the neuronal cell death and neuritic network loss induced by the A␤ peptide. Moreover, the hippocampal neurons treated with this compound, showed an increase in the number of peroxisomes, with a concomitant increase in catalase activity. Additionally, we evaluate the Wy protective effect on ␤-catenin levels, production of intracellular reactive oxygen species, cytoplasmic calcium uptake, and mitochondrial potential in hippocampal neurons exposed to H 2 O 2 and A␤ peptide. Results show that the peroxisomal proliferation prevents ␤-catenin degradation, reactive oxygen species production, cytoplasmic calcium increase, and changes in mitochondrial viability. Our data suggest, for the first time, a direct link between peroxisomal proliferation and neuroprotection from A␤-induced degenerative changes.Peroxisomes are subcellular organelles found in most animal cells that perform diverse metabolic functions, including detoxification of reactive oxygen species (ROS) 2 through their matrix enzyme catalase (1-3) and regulation of the oxidative balance and fatty acid oxidation (4 -6). Peroxisomes are present in the cell bodies, dendrites, and presynaptic axon terminals of neuronal cells (7,8) as well as in growing neurites (9). Tau overexpression inhibits kinesin-dependent transport of peroxisomes, neurofilaments, and Golgi-derived vesicles into neurites (10), and it has been suggested that a loss of peroxisomes apparently makes neurons more vulnerable to oxidative stress (10). Peroxisome proliferators (PPs) are a class of structurally dissimilar industrial and pharmaceutical chemicals that were originally identified as inducers of peroxisome proliferation in rat and mouse hepatocytes (11,12). Several PPs have shown to bind to peroxisome proliferator-activated receptors (PPARs), these include Wy-14.643 (Wy), which binds with great affinity to PPAR␣ and induces a strong activation of this receptor (11). 4-Phenyl butyric (4-PB) is a PP that, in contrast to other PPs, is able to induce human peroxisome proliferation (13); however, the mechanism of peroxisome proliferation remains to be elucidated. According to Liu et al. (14), 4-PB activates PPARs in astrocytes; nevertheless, they suggested that peroxisome proliferation may be independent of PPAR␣ activation.Alzheimer disease (AD) is characterized by a progressive neurodegeneration associated with extracellular deposits of amyloid ␤-peptide (A␤) in the form of senile plaques (15,16). A␤ peptide acquires neurotoxic properties when it forms homo-oligomeric species (17) or heterooligomeric species with molecules associated with mature ...

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“…Lipids are modified by ROS and there is a strong regional correlation between lipid peroxides visualized as Thiobarbituric acid, antioxidant enzymes, the presence of senile plaques and neurofibrillary tangles in AD brain [54]. The Aβ induces lipid peroxidation of membranes [55,56] and lipid peroxidation products are involved in modification of proteins by covalent binding. 4-hydroxynonenal (4-HNE) an aldehydic product of membrane lipid peroxidation [57], generated following exposure of neuronal membranes to Aβ peptide [58,59], binds directly to tau, a microtubule-associated protein, inhibiting its dephosphorylation.…”

Section: Lipid Peroxidation By Rosmentioning

confidence: 99%

Role of Metals in Neuronal Apoptosis: Challenges Associated with Neurodegeneration

Bharathi

Ravid²,

Ks³

2006

CAR

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Apoptosis is a tightly controlled process in which cell death is executed through activation of specific signalling pathways. Within cells, there are positive and negative regulatory pathways of apoptosis, hence it is targeted as 'Double-edged sword', the balance between these pathways dictates the cell fate. The past decade has seen intense focus on the mechanisms of apoptosis. Many important observations on the various signalling pathways mediating apoptotic cell death have been made and our understanding of the importance of apoptosis in both normal growth and development and pathophysiology has greatly increased. In addition, mechanisms of metal-induced toxicity continue to be of interest given the ubiquitous nature of these contaminants. The purpose of this review is to summarize our current understanding of the apoptotic pathways that are initiated by metals in Alzheimer's disease. Increased understanding of metal-induced (direct) and metal-amyloid-β (indirect) linked neuronal cell death through the formation of reactive oxygen species (ROS) is critical to illuminate mechanisms of metal-induced cell death, as well as the potential role of metal speciation in neurodegeneration.

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Vitamin E protects against Alzheimer's amyloid peptide (25–35)-induced changes in neocortical synaptosomal membrane lipid structure and composition

Cited by 71 publications

References 20 publications

Enhancement of 45Ca2+ Influx and Voltage-dependent Ca2+ Channel Activity by β-Amyloid-(1–40) in Rat Cortical Synaptosomes and Cultured Cortical Neurons

Enhancement of 45Ca2+ Influx and Voltage-dependent Ca2+ Channel Activity by β-Amyloid-(1–40) in Rat Cortical Synaptosomes and Cultured Cortical Neurons

Peroxisomal Proliferation Protects from β-Amyloid Neurodegeneration

Role of Metals in Neuronal Apoptosis: Challenges Associated with Neurodegeneration

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