1
|
Dumont Y, Bastianetto S, Duranton A, Breton L, Quirion R. Immunohistochemical distribution of neuropeptide Y, peptide YY, pancreatic polypeptide-like immunoreactivity and their receptors in the epidermal skin of healthy women. Peptides 2015; 70:7-16. [PMID: 26002416 DOI: 10.1016/j.peptides.2015.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 05/07/2015] [Accepted: 05/12/2015] [Indexed: 11/19/2022]
Abstract
Few studies have suggested that neuropeptide Y (NPY) could play an important role in skin functions. However, the expression of NPY, the related peptides, peptide YY (PYY) and pancreatic polypeptide (PP) and their receptors have not been investigated in human skin. Using specific antisera directed against NPY, PYY, PP and the Y1, Y2, Y4 and Y5 receptor subtypes, we investigated here the expression of these markers. NPY-like immunoreactivity (ir) in the epidermal skin could not be detected. For the first time we report the presence of positive PP-like ir immunofluorescent signals in epidermal cells, i.e. keratinocytes of skin from three areas (abdomen, breast and face) obtained as surgical left-overs. The immunofluorescent signal of PP-like ir varies from very low to high level in all three areas. In contrast, PYY-like ir is only expressed in some cells and with varied level of intensity. Furthermore and for the first time we observed specific Y1 and Y4 receptor-like ir in all epidermal layers, while the Y2 and Y5 subtypes were absent. Interestingly, as seen in human epidermis, in Episkin, a reconstituted human epidermal layer, we detected the presence of PP-like as well as Y1-like and Y4-like ir. These data have shown the presence and distribution of PYY, PP and Y1 and Y4 receptors in the human skin and Episkin, suggesting possible novel roles of NPY related peptides and their receptors in skin homeostasis.
Collapse
Affiliation(s)
- Yvan Dumont
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montréal, QC, Canada H4H 1R3
| | - Stéphane Bastianetto
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montréal, QC, Canada H4H 1R3
| | | | | | - Rémi Quirion
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montréal, QC, Canada H4H 1R3.
| |
Collapse
|
2
|
Bastianetto S, Ménard C, Quirion R. Neuroprotective action of resveratrol. Biochim Biophys Acta Mol Basis Dis 2014; 1852:1195-201. [PMID: 25281824 DOI: 10.1016/j.bbadis.2014.09.011] [Citation(s) in RCA: 235] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 09/09/2014] [Accepted: 09/16/2014] [Indexed: 11/30/2022]
Abstract
Low-to-moderate red wine consumption appeared to reduce age-related neurological disorders including macular degeneration, stroke, and cognitive deficits with or without dementia. Resveratrol has been considered as one of the key ingredients responsible for the preventive action of red wine since the stilbene displays a neuroprotective action in various models of toxicity. Besides its well documented free radical scavenging and anti-inflammatory properties, resveratrol has been shown to increase the clearance of beta-amyloid, a key feature of Alzheimer's disease, and to modulate intracellular effectors associated with oxidative stress (e.g. heme oxygenase), neuronal energy homeostasis (e.g. AMP kinase), program cell death (i.e. AIF) and longevity (i.e. sirtuins). This article summarizes the most recent findings on mechanisms of action involved in the protective effects of this multi target polyphenol, and discusses its possible roles in the prevention of various age-related neurological disorders. This article is part of a Special Issue entitled: Resveratrol: Challenges in translating pre-clinical findings to improved patient outcomes.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Douglas Mental Health University Institute, McGill University, Montreal, QC H4H 1R3, Canada
| | - Caroline Ménard
- Douglas Mental Health University Institute, McGill University, Montreal, QC H4H 1R3, Canada; Department of Psychiatry, McGill University, Montreal, QC H3A 1A1, Canada; Laboratory of Neuroendocrinology of Aging, Centre Hospitalier de l'Université de Montréal Research Center, Montreal, QC H2X 0A9, Canada; Department of Medicine, University of Montreal, Montreal, QC H3T 1J4, Canada
| | - Rémi Quirion
- Douglas Mental Health University Institute, McGill University, Montreal, QC H4H 1R3, Canada; Department of Psychiatry, McGill University, Montreal, QC H3A 1A1, Canada.
| |
Collapse
|
3
|
Menard C, Bastianetto S, Quirion R. Neuroprotective effects of resveratrol and epigallocatechin gallate polyphenols are mediated by the activation of protein kinase C gamma. Front Cell Neurosci 2013; 7:281. [PMID: 24421757 PMCID: PMC3872731 DOI: 10.3389/fncel.2013.00281] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 12/15/2013] [Indexed: 01/08/2023] Open
Abstract
Polyphenols such as epigallocatechin gallate (EGCG) and resveratrol have received a great deal of attention because they may contribute to the purported neuroprotective action of the regular consumption of green tea and red wine. Many studies, including those published by our group, suggest that this protective action includes their abilities to prevent the neurotoxic effects of beta-amyloid, a protein whose accumulation likely plays a pivotal role in Alzheimer's disease. Moreover, the scavenging activities of polyphenols on reactive oxygen species and their inhibitory action of cyclooxygenase likely explain, at least in part, their antioxidant and anti-inflammatory activities. Besides these well-documented properties, the modulatory action of these polyphenols on intracellular signaling pathways related to cell death/survival (e.g., protein kinase C, PKC) has yet to be investigated in detail. Using rat hippocampal neuronal cells, we aimed to investigate here the effects of EGCG and resveratrol on cell death induced by GF 109203X, a selective inhibitor of PKC. The MTT/resazurin and spectrin assays indicated that EGCG and resveratrol protected against GF 109203X-induced cell death and cytoskeleton degeneration, with a maximal effect at 1 and 3 μM, respectively. Moreover, immunofluorescence data revealed that cells treated with these polyphenols increased PKC gamma (γ) activation and promoted neuronal interconnections. Finally, we found that the protective effects of both polyphenols on the cytoskeleton and synaptic plasticity were mediated by the PKCγ subunit. Taken together, the results suggest that PKC, and more specifically its γ subunit, plays a critical role in the protective action of EGCG and resveratrol on neuronal integrity.
Collapse
Affiliation(s)
- Caroline Menard
- Laboratory of Neuroendocrinology of Aging, Centre Hospitalier de l'Université de Montréal Research Center Montreal, QC, Canada ; Department of Medicine, University of Montreal Montreal, QC, Canada ; Douglas Mental Health University Institute, McGill University Montreal, QC, Canada ; Department of Psychiatry, McGill University Montreal, QC, Canada
| | - Stéphane Bastianetto
- Douglas Mental Health University Institute, McGill University Montreal, QC, Canada
| | - Rémi Quirion
- Douglas Mental Health University Institute, McGill University Montreal, QC, Canada ; Department of Psychiatry, McGill University Montreal, QC, Canada
| |
Collapse
|
4
|
Morales-Medina JC, Dumont Y, Benoit CE, Bastianetto S, Flores G, Fournier A, Quirion R. Role of neuropeptide Y Y1 and Y2 receptors on behavioral despair in a rat model of depression with co-morbid anxiety. Neuropharmacology 2012; 62:200-8. [DOI: 10.1016/j.neuropharm.2011.06.030] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2011] [Revised: 06/28/2011] [Accepted: 06/29/2011] [Indexed: 02/08/2023]
|
5
|
Bastianetto S, Krantic S, Chabot JG, Quirion R. Possible Involvement of Programmed Cell Death Pathways in the Neuroprotective Action of Polyphenols. Curr Alzheimer Res 2011; 8:445-51. [DOI: 10.2174/156720511796391854] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2010] [Accepted: 04/16/2011] [Indexed: 11/22/2022]
|
6
|
Bastianetto S, Dumont Y, Duranton A, Vercauteren F, Breton L, Quirion R. Protective action of resveratrol in human skin: possible involvement of specific receptor binding sites. PLoS One 2010; 5:e12935. [PMID: 20886076 PMCID: PMC2944869 DOI: 10.1371/journal.pone.0012935] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Accepted: 08/27/2010] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Resveratrol is a plant-derived polyphenol with purported protecting action on various disorders associated with aging. It has been suggested that resveratrol could exert its protective action by acting on specific plasma membrane polyphenol binding sites (Han Y.S., et al. (2006) J Pharmacol Exp Ther 318:238-245). The purpose of this study was to investigate, in human skin, the possible existence of specific binding sites that mediate the protective action of resveratrol. METHODS AND FINDINGS Using human skin tissue, we report here the presence of specific [(3)H]-resveratrol binding sites (K(D) = 180 nM) that are mainly located in the epidermis. Exposure of HaCaT cells to the nitric oxide free radical donor sodium nitroprusside (SNP; 0.3-3 mM) resulted in cell death which was reduced by resveratrol (EC(50) = 14.7 µM), and to a much lesser extent by the resveratrol analogue piceatannol (EC(50) = 95 µM) and epigallocatechin gallate (EC(50) = 200 µM), a green-tea derived polyphenol. The protective action of resveratrol likely relates to its anti-apoptotic effect since at the same range of concentration it was able to reduce both the number of apoptotic cells as well as mitochondrial apoptotic events triggered by SNP. CONCLUSION Taken together, these findings suggest that resveratrol, by acting on specific polyphenol binding sites in epidermis, may be useful to prevent skin disorders associated with aging.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, Quebec, Canada
| | - Yvan Dumont
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, Quebec, Canada
| | | | - Freya Vercauteren
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, Quebec, Canada
| | | | - Rémi Quirion
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, Quebec, Canada
- * E-mail:
| |
Collapse
|
7
|
Bastianetto S, Quirion R. Heme oxygenase 1: another possible target to explain the neuroprotective action of resveratrol, a multifaceted nutrient-based molecule. Exp Neurol 2010; 225:237-9. [PMID: 20603117 DOI: 10.1016/j.expneurol.2010.06.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Accepted: 06/25/2010] [Indexed: 11/27/2022]
Abstract
Resveratrol, a polyphenol present in red wine, has received much attention lately because of its putative preventive role in the purported link between moderate red wine consumption and lower incidence of neurological disorders such as dementia and stroke. Numerous animal and in vitro studies have shown that this polyphenol is neuroprotective and can reverse various types of cognitive deficits. However, the mechanism(s) of action involved in the multiple effects of resveratrol is not fully understood. In a recent article by Sakata and colleagues in Experimental Neurology (Sakata, Y., Zhuang, H., Kwansa, H., Koehler, R.C., Doré, S., 2010. Resveratrol protects against experimental stroke: putative neuroprotective role of heme oxygenase 1. Exp. Neurol. 224, 325-329.), the authors raise a hypothesis that the induction of heme oxygenase 1, an endogenous enzyme that provides resistance against oxidative stress-related neuronal damage, contributes, at least in part, to the neuroprotective action of resveratrol. Our brief commentary summarizes recent findings on intracellular pathways possibly involved in the effects of a multi-functional molecule, such as resveratrol, and highlights their relevance in various age-related neurological disorders.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, QC, Canada
| | | |
Collapse
|
8
|
Bastianetto S, Krantic S, Quirion R. P3‐316: Anti‐apoptotic action of polyphenols derived from red wine and green tea against beta‐amyloid in hippocampal cells. Alzheimers Dement 2010. [DOI: 10.1016/j.jalz.2010.05.1817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Rémi Quirion
- Douglas Mental Health University InstituteVerdun QC Canada
| |
Collapse
|
9
|
Bastianetto S, Dumont Y, Han Y, Quirion R. Comparative neuroprotective properties of stilbene and catechin analogs: action via a plasma membrane receptor site? CNS Neurosci Ther 2009; 15:76-83. [PMID: 19228181 DOI: 10.1111/j.1755-5949.2008.00074.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Various studies have reported on the neuroprotective effects of polyphenols, widely present in food, beverages, and natural products. For example, we have shown that resveratrol, a polyphenol enriched in red wine and other foods such as peanuts, protects hippocampal cells against beta-amyloid (Abeta)-induced toxicity, a key protein involved in the neuropathology of Alzheimer disease. This effect involves, at least in part, the capacity of resveratrol to activate the phosphorylation of delta isoform of protein kinase C (PKC-delta). The neuroprotective action of resveratrol is shared by piceatannol, a stilbene derivative, as well as by tea-derived catechin gallate esters. The thioflavin T assay indicated that all these polyphenols inhibited the formation of Abeta fibrils, suggesting that this action likely also contributes to their neuroprotective effects. Binding and autoradiographic studies revealed that the effects of polyphenols might involve specific binding sites that are particularly enriched in the choroid plexus in the rat brain. Interestingly, the choroid plexus secretes transthyretin, a protein that has been shown to modulate Abeta aggregation and that may be critical to the maintenance of normal learning capacities in aging. Taken together, these data suggest that polyphenols target multiple enzymes/proteins, leading to their neuroprotective actions, possibly through action via specific plasma membrane binding sites.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, 6875 LaSalle Boulevard,Montréal, Québec, Canada
| | | | | | | |
Collapse
|
10
|
Rajah M, Bastianetto S, Bromley-Brits K, Cools R, D’Esposito M, Grady C, Poirier J, Quirion R, Raz N, Rogaeva E, Song W, Pruessner J. Biological changes associated with healthy versus pathological aging: a symposium review. Ageing Res Rev 2009; 8:140-6. [PMID: 19274854 DOI: 10.1016/j.arr.2009.01.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The Douglas Mental Health University Institute, in collaboration with the McGill Centre for Studies in Aging, organized a 2-day symposium entitled "Biological Changes Associated with Healthy Versus Pathological Aging" that was held in 13 and 14 December 2007 on the Douglas campus. The symposium involved presentations on current trends in aging and dementia research across several sub-disciplines: genetics, neurochemistry, structural and functional neuroimaging and clinical treatment and rehabilitation. The goal of this symposium was to provide a forum for knowledge-transfer between scientists and clinicians with different specializations in order to promote cross-fertilization of research ideas that would lead to future collaborative neuroscience research in aging and dementia. In this review article, we summarize the presentations made by the 13 international scientists at the symposium and highlight: (i) past research, and future research trends in neuroscience of aging and dementia and (ii) links across levels of analysis that can lead to fruitful transdisciplinary research programs that will advance knowledge about the neurobiological changes associated with healthy aging and dementia.
Collapse
|
11
|
Bastianetto S, Krantic S, Quirion R. Polyphenols as Potential Inhibitors of Amyloid Aggregation and Toxicity:Possible Significance to Alzheimers Disease. Mini Rev Med Chem 2008; 8:429-35. [DOI: 10.2174/138955708784223512] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
12
|
Bastianetto S, Brouillette J, Quirion R. Neuroprotective effects of natural products: interaction with intracellular kinases, amyloid peptides and a possible role for transthyretin. Neurochem Res 2007; 32:1720-5. [PMID: 17406978 DOI: 10.1007/s11064-007-9333-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Accepted: 03/16/2007] [Indexed: 12/20/2022]
Abstract
Various studies reported on the neuroprotective effects of natural products, particularly polyphenols, widely present in food and beverages. For example, we have shown that resveratrol, a polyphenol contained present in red wine and other foods, activates the phosphorylation of protein kinase C (PKC), this effect being involved in its neuroprotective action against Ass-induced toxicity. Moreover, tea-derived catechin gallate esters inhibit the formation Ass oligomers/fibrils, suggesting that this action likely contributes to their neuroprotective effects. Interestingly, the effects of polyphenols may be attributable, at least in part, to the presence of specific binding sites. Autoradiographic studies revealed that these binding sites are particularly enriched in choroids plexus in the rat brain. Interestingly, the choroid plexus secretes transthyretin, a protein that has been shown to prevent Abeta aggregation and that may be critical to the maintenance of normal learning capacities in aging. Taken together, these data suggest that polyphenols target multiple enzymes/proteins leading to their neuroprotective actions.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 LaSalle Boulevard, Verdun, Montreal, QC, Canada, H4H 1R3
| | | | | |
Collapse
|
13
|
Bastianetto S, Danik M, Mennicken F, Williams S, Quirion R. Prototypical antipsychotic drugs protect hippocampal neuronal cultures against cell death induced by growth medium deprivation. BMC Neurosci 2006; 7:28. [PMID: 16573831 PMCID: PMC1448194 DOI: 10.1186/1471-2202-7-28] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2005] [Accepted: 03/30/2006] [Indexed: 12/21/2022] Open
Abstract
Background Several clinical studies suggested that antipsychotic-based medications could ameliorate cognitive functions impaired in certain schizophrenic patients. Accordingly, we investigated the effects of various dopaminergic receptor antagonists – including atypical antipsychotics that are prescribed for the treatment of schizophrenia – in a model of toxicity using cultured hippocampal neurons, the hippocampus being a region of particular relevance to cognition. Results Hippocampal cell death induced by deprivation of growth medium constituents was strongly blocked by drugs including antipsychotics (10-10-10-6 M) that display nM affinities for D2 and/or D4 receptors (clozapine, haloperidol, (±)-sulpiride, domperidone, clozapine, risperidone, chlorpromazine, (+)-butaclamol and L-741,742). These effects were shared by some caspases inhibitors and were not accompanied by inhibition of reactive oxygen species. In contrast, (-)-raclopride and remoxipride, two drugs that preferentially bind D2 over D4 receptors were ineffective, as well as the selective D3 receptor antagonist U 99194. Interestingly, (-)-raclopride (10-6 M) was able to block the neuroprotective effect of the atypical antipsychotic clozapine (10-6 M). Conclusion Taken together, these data suggest that D2-like receptors, particularly the D4 subtype, mediate the neuroprotective effects of antipsychotic drugs possibly through a ROS-independent, caspase-dependent mechanism.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, 6875 LaSalle Boulevard, Montreal, Québec, H4H 1R3, Canada
| | - Marc Danik
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, 6875 LaSalle Boulevard, Montreal, Québec, H4H 1R3, Canada
| | - Françoise Mennicken
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, 6875 LaSalle Boulevard, Montreal, Québec, H4H 1R3, Canada
| | - Sylvain Williams
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, 6875 LaSalle Boulevard, Montreal, Québec, H4H 1R3, Canada
| | - Rémi Quirion
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, 6875 LaSalle Boulevard, Montreal, Québec, H4H 1R3, Canada
| |
Collapse
|
14
|
Han YS, Bastianetto S, Dumont Y, Quirion R. Specific Plasma Membrane Binding Sites for Polyphenols, Including Resveratrol, in the Rat Brain. J Pharmacol Exp Ther 2006; 318:238-45. [PMID: 16574779 DOI: 10.1124/jpet.106.102319] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Using [3H]resveratrol (3,5,4'-trihydroxy-trans-stilbene) as radioligand, we investigated the possible existence of specific polyphenol binding sites at the level of the cellular plasma membrane in rat brain. Specific [3H]resveratrol binding sites were found to be enriched in the plasma membrane pellet with lower levels in the nuclear and cell debris fraction. Specific [3H]resveratrol binding to the plasma membrane fraction was sensitive to trypsin digestion and protein denaturation but not to DNase and RNase treatment. Saturation binding experiments revealed that specific [3H]resveratrol recognized a single class of sites with an apparent affinity (KD) of 220+/-45 nM and a maximal capacity (Bmax) of 1060+/-120 fmol/mg protein. Various polyphenols and resveratrol derivatives competed against specific [3H]resveratrol binding in rat brain plasma membrane homogenates with the tea catechin gallates (epigallocatechin gallate and epicatechin gallate) displaying the highest affinities (Ki=25-45 nM) followed by resveratrol (Ki=102 nM). Quantitative autoradiographic studies revealed that specific [3H]resveratrol binding sites are broadly distributed in the rat brain, with highest levels of labeling seen in the choroid plexus and subfornical organ. Finally, the potency of various polyphenols and resveratrol analogs in protecting hippocampal cells against beta-amyloid-induced toxicity correlated well (r=0.74) with their apparent affinity in the [3H]resveratrol binding assay. Taken together, these results suggest that the neuroprotective action of various polyphenols and resveratrol analogs could be mediated by the activation of common "receptor" binding sites particularly enriched at the level of the cellular plasma membrane in the rat brain.
Collapse
Affiliation(s)
- Ying-Shan Han
- Douglas Hospital Research Center, Department of Psychiatry, McGill University, 6875 Blvd. LaSalle, Montréal (Verdun), QC H4H 1R3, Canada
| | | | | | | |
Collapse
|
15
|
Bastianetto S, Yao ZX, Papadopoulos V, Quirion R. Neuroprotective effects of green and black teas and their catechin gallate esters against β-amyloid-induced toxicity. Eur J Neurosci 2006; 23:55-64. [PMID: 16420415 DOI: 10.1111/j.1460-9568.2005.04532.x] [Citation(s) in RCA: 227] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Teas represent a large family of plants containing high amounts of polyphenols that may confer health benefits in various diseases. Recently, it has been hypothesized that tea consumption may also reduce the risk of age-related neurodegenerative pathologies. Considering the deleterious role of beta-amyloid (Abeta) in the aetiology of Alzheimer's disease (AD), we investigated green and black tea extracts and flavan-3-ols (present as monomers and dimers in green and black forms, respectively) against toxicity induced by Abeta-derived peptides using primary cultures of rat hippocampal cells as model. Both green and black tea extracts (5-25 microg/mL) displayed neuroprotective action against Abeta toxicity. These effects were shared by gallic acid (1-20 microm), epicatechin gallate (ECG; 1-20 microM) and epigallocatechin gallate (EGCG; 1-10 microM), the former being the most potent flavan-3-ol. In contrast, epicatechin and epigallocatechin were ineffective in the same range of concentrations. Moreover, only tea flavan-3-ol gallate esters (i.e. ECG, EGCG) and gallic acid inhibited apoptotic events induced by Abeta(25-35). Interestingly, EGCG and gallic acid inhibited Abeta aggregation and/or the formation of Abeta-derived diffusible neurotoxin ligands. Taken together, these results indicate that the catechin gallates (through the galloyl moiety) contribute to the neuroprotective effects of both green and black teas. Moreover, the protective effect of EGCG is likely to be associated, at least in part, with its inhibitory action on Abeta fibrils/oligomers formation. These data also support the hypothesis that not only green but also black teas may reduce age-related neurodegenerative diseases, such as AD.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, 6875 Blvd LaSalle, Verdun, Québec, Canada H4H 1R3
| | | | | | | |
Collapse
|
16
|
Han YS, Zheng WH, Bastianetto S, Chabot JG, Quirion R. Neuroprotective effects of resveratrol against beta-amyloid-induced neurotoxicity in rat hippocampal neurons: involvement of protein kinase C. Br J Pharmacol 2005; 141:997-1005. [PMID: 15028639 PMCID: PMC1574264 DOI: 10.1038/sj.bjp.0705688] [Citation(s) in RCA: 220] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
1. Resveratrol, an active ingredient of red wine extracts, has been shown to exhibit neuroprotective effects in several experimental models. 2. The present study evaluated the neuroprotective effects of resveratrol against amyloid beta(Abeta)-induced toxicity in cultured rat hippocampal cells and examined the role of the protein kinase C (PKC) pathway in this effect. 3. Pre-, co- and post-treatment with resveratrol significantly attenuated Abeta-induced cell death in a concentration-dependent manner, with a concentration of 25 microm being maximally effective. 4. Pretreatment (1 h) of hippocampal cells with phorbol-12-myristate-13-acetate, a PKC activator, at increasing concentrations (1-100 ng x ml(-1)), resulted in a dose-dependent reduction in Abeta-induced toxicity, whereas the inactive 4alpha-phorbol had no effect. 5. Pretreatment (30 min) of hippocampal cells with GF 109203X (1 microm), a general PKC inhibitor, significantly attenuated the neuroprotective effect of resveratrol against Abeta-induced cell death. 6. Treatment of hippocampal cells with resveratrol (20 microm) also induced the phosphorylation of various isoforms of PKC leading to activation. 7. Taken together, the present results indicate that PKC is involved in the neuroprotective action of resveratrol against Abeta-induced toxicity.
Collapse
Affiliation(s)
- Ying-Shan Han
- Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 Boulevard LaSalle, Montreal, Québec, Canada H4H 1R3
| | - Wen-Hua Zheng
- Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 Boulevard LaSalle, Montreal, Québec, Canada H4H 1R3
| | - Stéphane Bastianetto
- Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 Boulevard LaSalle, Montreal, Québec, Canada H4H 1R3
| | - Jean-Guy Chabot
- Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 Boulevard LaSalle, Montreal, Québec, Canada H4H 1R3
| | - Rémi Quirion
- Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 Boulevard LaSalle, Montreal, Québec, Canada H4H 1R3
- Author for correspondence:
| |
Collapse
|
17
|
Abstract
Neurodegenerative diseases such as Alzheimer's (AD) and Parkinson's (PD) diseases are defined by a progressive neuronal dysfunction and an ensuing behavioral dysfunction. Although protein aggregation (i.e beta-amyloid and alpha-synuclein) plays a pivotal role in both AD and PD, there is increasing evidence that excessive accumulation of reactive oxygen species (ROS) that occurs during normal and pathological brain aging contributes to neuronal losses and dysfunction. Based on these observations, it has been hypothesized that natural antioxidants derived from food, beverages and natural extracts may be beneficial to prevent or delay the occurrence of age-related cognitive deficits and neurodegenerative diseases. We will summarize in this review the role of oxidative stress in pathological brain aging, and provide evidence for a role for antioxidant molecules as therapeutic agents. We will also focus on the various mechanisms underlying their neuroprotective effects in in vivo and in vitro models of neurotoxicity.
Collapse
Affiliation(s)
- S Bastianetto
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, 6875 LaSalle Boulevard, Montreal, Quebec, H4H 1R3 Canada
| | | |
Collapse
|
18
|
Zheng WH, Bastianetto S, Mennicken F, Ma W, Kar S. Amyloid beta peptide induces tau phosphorylation and loss of cholinergic neurons in rat primary septal cultures. Neuroscience 2003; 115:201-11. [PMID: 12401334 DOI: 10.1016/s0306-4522(02)00404-9] [Citation(s) in RCA: 240] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The neuropathological features associated with Alzheimer's disease (AD) brain include the presence of extracellular neuritic plaques composed of amyloid beta protein (Abeta), intracellular neurofibrillary tangles containing phosphorylated tau protein and the loss of basal forebrain cholinergic neurons which innervate regions such as the hippocampus and the cortex. Studies of the pathological changes that characterize AD and several other lines of evidence indicate that Abeta accumulation in vivo may initiate phosphorylation of tau protein, which by disrupting neuronal network may trigger the process of neurodegeneration observed in AD brains. However, the underlying cause of degeneration of the basal forebrain cholinergic neurons and their association, if any, to Abeta peptides or phosphorylated tau remains mostly unknown. In the present study, using rat primary septal cultures, we have shown that aggregated Abeta peptides, in a time (18-96 h)- and concentration (0.7-60 microM)-dependent manner, induce toxicity and decrease choline acetyltransferase enzyme activity in cultured neurons. Using immunocytochemistry and immunoblotting, we have also demonstrated that Abeta treatment can significantly increase the phosphorylation of tau protein in septal cultures. At the cellular level, hyperphosphorylated tau is mostly apparent in the somatodendritic compartment of the neurons. Abeta peptide (10 microM), in addition to tau phosphorylation, also activates mitogen-activated protein kinase and glycogen synthase kinase-3beta, the two kinases which are known to be involved in the formation of hyperphosphorylated tau in the AD brain. Exposure to specific inhibitors of the mitogen-activated protein kinase (i.e. PD98059) or glycogen synthase kinase-3beta (i.e. LiCl) attenuated the hyperphosphorylation of the tau protein in cultured neurons. Given the evidence that tau phosphorylation can induce cell loss by disrupting neuronal cytoskeleton, it is likely that aggregated Abeta peptide triggers degeneration of septal neurons, including those expressing the cholinergic phenotype, by phosphorylation of the tau protein activated by mitogen-activated protein kinase and glycogen synthase kinase-3beta. These results, taken together, suggest that cultured septal cholinergic neurons are vulnerable to Abeta-mediated toxicity and tau phosphorylation may play an important role in Abeta-induced neurodegeneration.
Collapse
Affiliation(s)
- W-H Zheng
- Douglas Hospital Research Center, Department of Psychiatry, McGill University, 6875 La Salle Boulevard, Verdun, QC, Canada H4H 1R3
| | | | | | | | | |
Collapse
|
19
|
Auld DS, Kornecook TJ, Bastianetto S, Quirion R. Alzheimer's disease and the basal forebrain cholinergic system: relations to beta-amyloid peptides, cognition, and treatment strategies. Prog Neurobiol 2002; 68:209-45. [PMID: 12450488 DOI: 10.1016/s0301-0082(02)00079-5] [Citation(s) in RCA: 472] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Alzheimer's disease (AD) is the most common form of degenerative dementia and is characterized by progressive impairment in cognitive function during mid- to late-adult life. Brains from AD patients show several distinct neuropathological features, including extracellular beta-amyloid-containing plaques, intracellular neurofibrillary tangles composed of abnormally phosphorylated tau, and degeneration of cholinergic neurons of the basal forebrain. In this review, we will present evidence implicating involvement of the basal forebrain cholinergic system in AD pathogenesis and its accompanying cognitive deficits. We will initially discuss recent results indicating a link between cholinergic mechanisms and the pathogenic events that characterize AD, notably amyloid-beta peptides. Following this, animal models of dementia will be discussed in light of the relationship between basal forebrain cholinergic hypofunction and cognitive impairments in AD. Finally, past, present, and future treatment strategies aimed at alleviating the cognitive symptomatology of AD by improving basal forebrain cholinergic function will be addressed.
Collapse
Affiliation(s)
- Daniel S Auld
- Douglas Hospital Research Centre, 6875 Blvd Lasalle, Verdun, Que, Canada H4H 1R3
| | | | | | | |
Collapse
|
20
|
Bastianetto S, Quirion R. EGb 761 is a neuroprotective agent against beta-amyloid toxicity. Cell Mol Biol (Noisy-le-grand) 2002; 48:693-7. [PMID: 12396081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Beta-amyloid (Abeta) deposition likely plays a causal role in the lesions that occur in Alzheimer's disease (AD). The Ginkgo biloba extract EGb 761 is widely prescribed in the treatment of cognitive deficits that are associated with normal and pathological brain aging such as AD. We have investigated here the potential effectiveness of EGb 761 against cell death produced by Abeta fragments on primary cultures of hippocampal cells, these cells being severely damaged in AD. A co-treatment with EGb 761 protected cells against toxicity induced by Abeta fragments in a concentration dependent manner. The effect of EGb 761 was even significant if added up to 8 hr to cells and was shared by its flavonoid fraction CP 205, whereas the terpenes bilobalide and ginkgolide B were ineffective. EGb 761 also displayed protective effects against toxicity produced by either H2O2 or nitric oxide, two neurotoxic agents that possibly mediate Abeta toxicity. Moreover, EGb 761, and to a lesser extent CP 205, completely blocked Abeta-induced events, such as reactive oxygen species accumulation and apoptosis. Taken together, these results and those obtained by other groups highlight the neuroprotective abilities of EGb 761 against dysfunction and death of neurons caused by Abeta deposits.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Douglas Hospital Research Centre, Department of Psychiatry and Pharmacology and Therapeutics, McGill University, Verdun, Quebec, Canada
| | | |
Collapse
|
21
|
Abstract
A growing number of studies suggest that natural extracts and phytochemicals have a positive impact on brain aging. We examined the potential of the Ginkgo biloba extract EGb 761 and red wine-derived constituents on cell death produced by beta-amyloid (Abeta) peptides and oxidative stress, with respect to their possible deleterious role in age-related neurological disorders. We found that EGb 761, possibly through the antioxidant properties of its flavonoids, was able to protect hippocampal cells against toxic effects induced by Abeta peptides. Moreover, we showed that an exposure of rat hippocampal cells to the nitric oxide (NO) donor sodium nitroprusside (SNP) resulted in a decrease in cell survival and increase in reactive oxygen species (ROS) accumulation. However, EGb 761 and red wine-derived polyphenols protected against these events, due to their antioxidant activities, and their ability to block SNP-stimulated activity of protein kinase C (PKC). Taken together, these results support the hypothesis that dietary intake of natural substances may be beneficial in normal aging of the brain.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Department of Psychiatry and Pharmacology and Therapeutics, Douglas Hospital Research Centre, McGill University, 6875 LaSalle Boulevard, Verdun, Que, Canada H4H 1R3
| | | |
Collapse
|
22
|
|
23
|
Bastianetto S, Zheng WH, Quirion R. Neuroprotective abilities of resveratrol and other red wine constituents against nitric oxide-related toxicity in cultured hippocampal neurons. Br J Pharmacol 2000; 131:711-20. [PMID: 11030720 PMCID: PMC1572384 DOI: 10.1038/sj.bjp.0703626] [Citation(s) in RCA: 239] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Animal and epidemiological studies suggest that polyphenol constituents of red wine possess antioxidant activities that favour protection against cardiovascular disease - the so-called. 'French paradox' - and possibly, central nervous system disorders such as Alzheimer's disease (AD) and ischaemia. In the present study, the potential of three major red wine derived-polyphenols to protect against toxicity induced by the nitric oxide free radical donors sodium nitroprusside (SNP) and 3-morpholinosydnonimine (SIN-1) was examined in cultured rat hippocampal cells. Both co- and post-treatments with either the stilbene resveratrol (5 - 25 microM) or the flavonoids quercetin (5 - 25 microM) and (+)-catechin (1 - 10 microM) were capable of attenuating hippocampal cell death and intracellular reactive oxygen species accumulation produced by SNP (100 microM and 1 mM, respectively). However, among the phenolic compounds tested, only the flavonoids afforded significant protection against 5 mM SIN-1-induced toxicity. The effects of phenolic constituents were shared by Trolox (100 microM), a vitamin E analogue, but not by selective inhibitors of cyclo-oxygenases (COX) and lipoxygenases (LOX). Among the phenolic compounds tested, only quercetin (10 microM) inhibited 100 microM SNP-stimulated protein kinase C (PKC) activation, whereas none of them were able to attenuate nitrite accumulation caused by SNP (100 microM). Taken together, these data suggest that the neuroprotective abilities of quercetin, resveratrol, and (+)-catechin result from their antioxidant properties rather than their purported inhibitory effects on intracellular enzymes such as COX, LOX, or nitric oxide synthase. Quercetin, however, may also act via PKC to produce its protective effects.
Collapse
Affiliation(s)
- Stéphane Bastianetto
- Department of Psychiatry, Pharmacology and Therapeutics, Douglas Hospital Research Centre, McGill University, 6875 Bld LaSalle, Verdun, Québec, H4H 1R3 Canada
| | - Wen-Hua Zheng
- Department of Psychiatry, Pharmacology and Therapeutics, Douglas Hospital Research Centre, McGill University, 6875 Bld LaSalle, Verdun, Québec, H4H 1R3 Canada
| | - Rémi Quirion
- Department of Psychiatry, Pharmacology and Therapeutics, Douglas Hospital Research Centre, McGill University, 6875 Bld LaSalle, Verdun, Québec, H4H 1R3 Canada
- Author for correspondence:
| |
Collapse
|
24
|
Bastianetto S, Ramassamy C, Doré S, Christen Y, Poirier J, Quirion R. The Ginkgo biloba extract (EGb 761) protects hippocampal neurons against cell death induced by beta-amyloid. Eur J Neurosci 2000; 12:1882-90. [PMID: 10886329 DOI: 10.1046/j.1460-9568.2000.00069.x] [Citation(s) in RCA: 274] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Substantial evidence suggests that the accumulation of beta-amyloid (Abeta)-derived peptides, and to a lesser extent free radicals, may contribute to the aetiology and/or progression of Alzheimer's disease (AD). Ginkgo biloba extract (EGb 761) is a well-defined plant extract containing two major groups of constituents, i.e. flavonoids and terpenoids. It is viewed as a polyvalent agent with a possible therapeutic use in the treatment of neurodegenerative diseases of multifactorial origin, e.g. AD. We have investigated here the potential effectiveness of EGb 761 against toxicity induced by (Abeta)-derived peptides (Abeta25-35, Abeta1-40 and Abeta1-42) on hippocampal primary cultured cells, this area being severely affected in AD. A co-treatment with EGb 761 concentration-dependently (10-100 microg/mL) protected hippocampal neurons against toxicity induced by Abeta fragments, with a maximal and complete protection at the highest concentration tested. Similar, albeit less potent protective effects were seen with the flavonoid fraction of the extract (CP 205), while the terpenes were ineffective. Most interestingly, EGb 761 (100 microg/mL) was even able to protect (up to 8 h) hippocampal cells from a pre-exposure to Abeta25-35 and Abeta1-40. EGb 761 was also able to both protect and rescue hippocampal cells from toxicity induced by H2O2 (50-150 microM), a major peroxide possibly involved in mediating Abeta toxicity. Moreover, EGb 761 (10-100 microg/mL), and to a lesser extent CP 205 (10-50 microg/mL), completely blocked Abeta-induced events, e.g. reactive oxygen species accumulation and apoptosis. These results suggest that the neuroprotective effects of EGb 761 are partly associated with its antioxidant properties and highlight its possible effectiveness in neurodegenerative diseases, e.g. AD via the inhibition of Abeta-induced toxicity and cell death.
Collapse
Affiliation(s)
- S Bastianetto
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, 6875 Bld LaSalle, Verdun, Québec, Canada
| | | | | | | | | | | |
Collapse
|
25
|
Bastianetto S, Zheng WH, Quirion R. The Ginkgo biloba extract (EGb 761) protects and rescues hippocampal cells against nitric oxide-induced toxicity: involvement of its flavonoid constituents and protein kinase C. J Neurochem 2000; 74:2268-77. [PMID: 10820186 DOI: 10.1046/j.1471-4159.2000.0742268.x] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
An excess of the free radical nitric oxide (NO) is viewed as a deleterious factor involved in various CNS disorders. Numerous studies have shown that the Ginkgo biloba extract EGb 761 is a NO scavenger with neuroprotective properties. However, the mechanisms underlying its neuroprotective ability remain to be fully established. Thus, we investigated the effect of different constituents of EGb 761, i.e., flavonoids and terpenoids, against toxicity induced by NO generators on cells of the hippocampus, a brain area particularly susceptible to neurodegenerative damage. Exposure of rat primary mixed hippocampal cell cultures to either sodium nitroprusside (SNP; 100 microM) or 3-morpholinosydnonimine resulted in both a decrease in cell survival and an increase in free radical accumulation. These SNP-induced events were blocked by either EGb 761 (10-100 microg/ml) or its flavonoid fraction CP 205 (25 microg/ml), as well as by inhibitors of protein kinase C (PKC; chelerythrine) and L-type calcium channels (nitrendipine). In contrast, the terpenoid constituents of EGb 761, known as bilobalide and ginkgolide B, as well as inhibitors of phospholipases A [3-[(4-octadecyl)benzoyl]acrylic acid (OBAA)] and C (U-73122), failed to display any significant effects. Moreover, EGb 761 (50 microm) CP 205 (25 microg/ml), and chelerythrine were also able to rescue hippocampal cells preexposed to SNP (up to 1 mM). Finally, EGb 761 (100 microg/ml) was shown to block the activation of PKC induced by SNP (100 microM). These data suggest that the protective and rescuing abilities of EGb 761 are not only attributable to the antioxidant properties of its flavonoid constituents but also via their ability to inhibit NO-stimulated PKC activity.
Collapse
Affiliation(s)
- S Bastianetto
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, Verdun, Québec, Canada
| | | | | |
Collapse
|
26
|
Doré S, Bastianetto S, Kar S, Quirion R. Protective and rescuing abilities of IGF-I and some putative free radical scavengers against beta-amyloid-inducing toxicity in neurons. Ann N Y Acad Sci 2000; 890:356-64. [PMID: 10668442 DOI: 10.1111/j.1749-6632.1999.tb08015.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
beta-Amyloid (A beta) peptides are most likely involved in the neurodegenerative process occurring in Alzheimer's Disease (AD) and are enriched in senile plaques. The mechanisms of A beta toxicity are not clear but likely involve free radicals and apoptosis. Much interest is currently aiming at developing effective approaches to block A beta toxicity in order to slow down disease progression. In that context, we are particularly interested in studying the role of insulin-like growth factors, particularly IGF-I and purported free radical scavengers including a Gingko biloba extract (EGb761) as blocker of A beta toxicity in a simple in vitro model of hippocampal primary cultures. We observed that both IGF-I and EGb761 are unique in that they are able not only to protect but even to rescue neurons against A beta toxicity. These results are summarized here and possible mechanisms of action are discussed to explain the protective properties of these two classes of agents.
Collapse
Affiliation(s)
- S Doré
- Douglas Hospital Research Center, McGill University, Montreal, Quebec, Canada
| | | | | | | |
Collapse
|
27
|
Ramassamy C, Averill D, Beffert U, Bastianetto S, Theroux L, Lussier-Cacan S, Cohn JS, Christen Y, Davignon J, Quirion R, Poirier J. Oxidative damage and protection by antioxidants in the frontal cortex of Alzheimer's disease is related to the apolipoprotein E genotype. Free Radic Biol Med 1999; 27:544-53. [PMID: 10490274 DOI: 10.1016/s0891-5849(99)00102-1] [Citation(s) in RCA: 181] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A great number of epidemiological studies have demonstrated that the frequency of the epsilon4 allele of the apolipoprotein E gene (APOE) is markedly higher in sporadic and in familial late onset Alzheimer disease (AD). In the frontal cortex of AD patients, oxidative damage is elevated. We address the hypothesis that the APOE genotype and reactive oxygen-mediated damage are linked in the frontal cortex of AD patients. We have related the APOE genotype to the levels of lipid oxidation (LPO) and to the antioxidant status, in frontal cortex tissues from age-matched control and AD cases with different APOE genotypes. LPO levels were significantly elevated in tissues from Alzheimer's cases which are homozygous for the epsilon4 allele of APOE, compared to AD epsilon3/epsilon3 cases and controls. Activities of enzymatic antioxidants, such as catalase and glutathione peroxidase (GSH-PX), were also higher in AD cases with at least one epsilon4 allele of APOE, while superoxide dismutase (SOD) activity was unchanged. In the frontal cortex, the concentration of apoE protein was not different between controls and AD cases, and was genotype independent. The Ginkgo biloba extract (EGb 761), the neurosteroid dehydroepiandrosterone (DHEA) and human recombinant apoE3 (hapoE3rec) were able to protect control, AD epsilon3/epsilon3 and epsilon3/epsilon4 cases against hydrogen peroxide/iron-induced LPO, while hapoE4rec was completely ineffective. Moreover, EGb 761 and DHEA had no effect in homozygous epsilon4 cases. These results demonstrate that oxidative stress-induced injury and protection by antioxidants in the frontal cortex of AD cases are related to the APOE genotype.
Collapse
Affiliation(s)
- C Ramassamy
- Neuroscience Division, Douglas Hospital Research Center, Verdun, Quebec, Canada
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Bastianetto S, Ramassamy C, Poirier J, Quirion R. Dehydroepiandrosterone (DHEA) protects hippocampal cells from oxidative stress-induced damage. Brain Res Mol Brain Res 1999; 66:35-41. [PMID: 10095075 DOI: 10.1016/s0169-328x(99)00002-9] [Citation(s) in RCA: 191] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
It has been postulated that decreases in plasma levels of dehydroepiandrosterone (DHEA) may contribute to the development of some age-related disorders. Along with neuroprotective and memory enhancing effects, DHEA has been shown to display antioxidant properties. Moreover, oxidative stress is known to cause lipid peroxidation and degenerative changes in the hippocampus, an area involved in memory processes and especially afflicted in Alzheimer's disease (AD). Accordingly, we investigated the antioxidant effects of DHEA in models of oxidative stress using rat primary hippocampal cells and human hippocampal tissue from AD patients and age-matched controls. A pre-treatment of rat primary mixed hippocampal cell cultures with DHEA (10-100 microM) protected against the toxicity induced by H2O2 and sodium nitroprusside. Moreover, DHEA (10-100 microM) was also able to prevent H2O2/FeSO4-stimulated lipid oxidation in both control and AD hippocampal tissues. Taken together, these data suggest that DHEA may be useful in treating age-related central nervous system diseases based on its protective effects in the hippocampus.
Collapse
Affiliation(s)
- S Bastianetto
- Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 LaSalle Boulevard, Verdun, Québec, Canada
| | | | | | | |
Collapse
|
29
|
Affiliation(s)
- S Bastianetto
- Douglas Hospital Research Centre, Faculty of Medicine, McGill University, Montréal, Québec, Canada
| | | |
Collapse
|
30
|
|
31
|
Bastianetto S, Rouquier L, Perrault G, Sanger DJ. DTG-induced circling behaviour in rats may involve the interaction between sigma sites and nigro-striatal dopaminergic pathways. Neuropharmacology 1995; 34:281-7. [PMID: 7630482 DOI: 10.1016/0028-3908(94)00156-m] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The distribution of sigma sites in brain areas enriched in dopamine, and the finding that circling behaviour can be elicited by specific sigma ligands such as DTG (di-o-tolylguanidine) suggest a modulatory role of these sites in the dopaminergic system. The present study was carried out to investigate further this hypothesis. Circling behaviour induced in rats by unilateral intranigral injection of DTG (10 nmol/rat) was decreased by haloperidol (0.1 mg/kg, i.p.), clebopride (0.25 mg/kg, i.p.) and SCH 23390 (0.03 mg/kg, s.c.) indicating that an interaction between sigma sites and the midbrain dopaminergic system may be involved in this rotational behaviour. Microdialysis experiments in freely moving rats showed that unilateral intranigral injection of DTG (5, 10, 20 nmol/rat) produced increases in extracellular levels of dopamine metabolites (DOPAC, HVA) in the ipsilateral striatum which correlated with the number of rotations. In addition intranigral injection of DTG (10 nmol/rat) produced increases in tissular dopamine metabolite levels in the ipsilateral striatum without affecting dopamine metabolite levels in limbic structures. These results indicate that sigma sites may be involved in the modulation of the dopaminergic motor system.
Collapse
|
32
|
Abstract
The central distribution of sigma sites labelled by di-o-tolylguanidine (DTG), a compound which has specific affinity for sigma sites, and its ability to produce postural movements, are consistent with the hypothesis that sigma sites may play a functional role in the regulation of movement. The aim of the present study was to evaluate the specificity of the circling behaviour induced by unilateral intranigral injection of DTG in rats. As previously described, DTG produced dose-dependent unilateral rotations (2.5-20 nmol/rat). A similar dose-dependent circling behaviour was observed with DMTG and (+) NANM (3-40 nmol/rat), compounds which bind to both sigma and PCP sites, and with haloperidol (3-20 nmol/rat) whereas raclopride and D,L-sulpiride did not elicit any circling (10 nmol/rat). DTG-induced circling after intranigral injection (10 nmol/rat) was decreased in a dose-dependent manner by rimcazole (20-40 mg/kg, i.p.), a selective ligand for sigma sites, and by BMY 14802 (3, 10, 30 mg/kg, i.p.), ifenprodil and eliprodil (1, 3, 10 mg/kg, i.p.), non-selective sigma ligands. In contrast, naloxone (1 mg/kg, s.c.) and CGS 19755 (1, 3, 10 mg/kg, i.p.) did not change the DTG-induced circling. Eliprodil failed to inhibit circling produced by compounds devoid of any affinity for sigma sites such as APV, dizocilpine or muscimol, indicating the specificity of the inhibition observed with eliprodil on the DTG-induced circling.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|