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Desbène C, Malaplate-Armand C, Youssef I, Garcia P, Stenger C, Sauvée M, Fischer N, Rimet D, Koziel V, Escanyé MC, Oster T, Kriem B, Yen FT, Pillot T, Olivier JL. Critical role of cPLA2 in Aβ oligomer-induced neurodegeneration and memory deficit. Neurobiol Aging 2011; 33:1123.e17-29. [PMID: 22188721 DOI: 10.1016/j.neurobiolaging.2011.11.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 11/03/2011] [Accepted: 11/04/2011] [Indexed: 12/23/2022]
Abstract
Soluble beta-amyloid (Aβ) oligomers are considered to putatively play a critical role in the early synapse loss and cognitive impairment observed in Alzheimer's disease. We previously demonstrated that Aβ oligomers activate cytosolic phospholipase A(2) (cPLA(2)), which specifically releases arachidonic acid from membrane phospholipids. We here observed that cPLA(2) gene inactivation prevented the alterations of cognitive abilities and the reduction of hippocampal synaptic markers levels noticed upon a single intracerebroventricular injection of Aβ oligomers in wild type mice. We further demonstrated that the Aβ oligomer-induced sphingomyelinase activation was suppressed and that phosphorylation of Akt/protein kinase B (PKB) was preserved in neuronal cells isolated from cPLA(2)(-/-) mice. Interestingly, expression of the Aβ precursor protein (APP) was reduced in hippocampus homogenates and neuronal cells from cPLA(2)(-/-) mice, but the relationship with the resistance of these mice to the Aβ oligomer toxicity requires further investigation. These results therefore show that cPLA(2) plays a key role in the Aβ oligomer-associated neurodegeneration, and as such represents a potential therapeutic target for the treatment of Alzheimer's disease.
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Affiliation(s)
- Cédric Desbène
- Lipidomix (EA 4422), INPL-ENSAIA, Université de Lorraine, Vandœuvre-lès-Nancy, France
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2
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Kim SJ, Jeong HJ, Kim BK, Kim NH, Kim JS, Choi KS, Lee HJ, Kang ST, Shin SS, Kim WI, Eom HS, Lee KM, Um JY, Hong SH, Kim HM. Anti-inflammatory effect of jeongshintang through suppression of p38 activation in human astrocytoma, U373MG cells. Exp Mol Pathol 2006; 81:85-91. [PMID: 16698013 DOI: 10.1016/j.yexmp.2005.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2005] [Revised: 11/18/2005] [Accepted: 12/01/2005] [Indexed: 01/22/2023]
Abstract
Jeongshintang (JST) is a Korean herbal prescription, which has been successfully used for cerebral diseases. However, the anti-inflammatory effect of JST on Alzheimer's disease (AD) is still not fully understood. In this study, we investigated the effects of JST in attenuating the inflammatory response induced by interleukin (IL)-1beta plus beta-amyloid [1-42] fragment (A beta) in the human astrocyte cell line, U373MG. The production of IL-6, IL-8, and prostaglandin (PG)E2 was significantly increased by IL-1beta plus A beta (1-42) in a time-dependent manner (P < 0.05). JST significantly inhibited the IL-1beta plus A beta (1-42)-induced IL-6, IL-8, and PGE2 production at 24 h (P < 0.05). Maximal inhibition rate of IL-6, IL-8, and PGE2 production by JST was about 54.40%, 56.01%, and 44.06% respectively. JST (0.01-1 mg/ml) also attenuated the expression of cyclooxygenase (COX)-2 and activation of p38 MAPK induced by IL-1beta and A beta (1-42). These results demonstrated that JST has an anti-inflammatory effect, which might explain its beneficial effect in the treatment of various neurodegenerative diseases such as AD.
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Affiliation(s)
- S J Kim
- College of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul 130-701, Republic of Korea
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3
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Mandel S, Weinreb O, Amit T, Youdim MBH. Cell signaling pathways in the neuroprotective actions of the green tea polyphenol (-)-epigallocatechin-3-gallate: implications for neurodegenerative diseases. J Neurochem 2004; 88:1555-69. [PMID: 15009657 DOI: 10.1046/j.1471-4159.2003.02291.x] [Citation(s) in RCA: 261] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Accumulating evidence supports the hypothesis that brain iron misregulation and oxidative stress (OS), resulting in reactive oxygen species (ROS) generation from H2O2 and inflammatory processes, trigger a cascade of events leading to apoptotic/necrotic cell death in neurodegenerative disorders, such as Parkinson's (PD), Alzheimer's (AD) and Huntington's diseases, and amyotrophic lateral sclerosis (ALS). Thus, novel therapeutic approaches aimed at neutralization of OS-induced neurotoxicity, support the application of ROS scavengers, transition metals (e.g. iron and copper) chelators and non-vitamin natural antioxidant polyphenols, in monotherapy, or as part of antioxidant cocktail formulation for these diseases. Both experimental and epidemiological evidence demonstrate that flavonoid polyphenols, particularly from green tea and blueberries, improve age-related cognitive decline and are neuroprotective in models of PD, AD and cerebral ischemia/reperfusion injuries. However, recent studies indicate that the radical scavenger property of green tea polyphenols is unlikely to be the sole explanation for their neuroprotective capacity and in fact, a wide spectrum of cellular signaling events may well account for their biological actions. In this article, the currently established mechanisms involved in the beneficial health action and emerging studies concerning the putative novel molecular neuroprotective activity of green tea and its major polyphenol (-)-epigallocatechin-3-gallate (EGCG), will be reviewed and discussed.
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Affiliation(s)
- Silvia Mandel
- Eve Topf and USA National Parkinson Foundation Centers of Excellence for Neurodegenerative Diseases Research and Department of Pharmacology, Technion-Faculty of Medicine, Haifa, Israel
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Villa A, Santiago J, García-Silva S, Ruiz-León Y, Pascual A. Serum is required for release of Alzheimer's amyloid precursor protein in neuroblastoma cells. Neurochem Int 2002; 41:261-9. [PMID: 12106777 DOI: 10.1016/s0197-0186(02)00019-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The beta-amyloid peptide, the major component of the senile plaques that characterize Alzheimer's disease, is generated from a set of alternatively spliced beta-amyloid precursor proteins (APPs), which are proteolytically cleaved by the action of a set of enzymes referred to generically as secretases. The major processing pathway involves the proteolytic cleavage of APP by alpha-secretase and results in the release of soluble non-amyloidogenic full-length amino terminal fragments (sAPP), which appear to be involved in neurotrophic events. A reduced production of these neuroprotective sAPP would contribute, together with deposition of the beta-amyloid peptide, to the neurodegenerative processes that lead to the cellular death in Alzheimer's disease. In the present work, we describe a dramatic reduction of sAPP content in medium conditioned by neuronal cells grown under low-serum conditions, when compared with the levels released in the presence of 10% serum. The inhibitory effect on sAPP release appears to be quite specific since that reduction occurs without major changes in cell proliferation, expression of APP-mRNA or intracellular APP levels. Under low-serum conditions, cells showed a more differentiated morphology and no apoptotic signs were observed. Since the alpha-secretase has been described as a membrane anchored protein, our results suggest that the serum contains an essential factor(s) involved in the alpha-secretase activity.
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Affiliation(s)
- Ana Villa
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas, Arturo Duperier 4, 28029 Madrid, Spain
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Avramovich Y, Amit T, Youdim MBH. Non-steroidal anti-inflammatory drugs stimulate secretion of non-amyloidogenic precursor protein. J Biol Chem 2002; 277:31466-73. [PMID: 12070143 DOI: 10.1074/jbc.m201308200] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Chronic inflammatory processes are associated with the pathophysiology of Alzheimer's disease (AD), and it has been proposed that treatment with non-steroidal anti-inflammatory drugs (NSAIDs) reduces the risk for AD. Here we report that various NSAIDs, such as the cyclooxygenase inhibitors, nimesulide, ibuprofen and indomethacin, as well as thalidomide (Thal) and its non-teratogenic analogue, supidimide, significantly stimulated the secretion of the non-amyloidogenic alpha-secretase form of the soluble amyloid precursor protein (sAPP alpha) into the conditioned media of SH-SY5Y neuroblastoma and PC12 cells. These NSAIDs markedly reduced the levels of the cellular APP holoprotein, further accelerating non-amyloidogenic processes. sAPP alpha release, induced by nimesulide and Thal, was modulated by inhibitors of protein kinase C and Erk mitogen-activated protein (MAP) kinase. Furthermore, in results complementary to the inhibitor studies, we show for the first time that NSAIDs can activate the Erk MAP kinase signaling cascade, thus identifying a novel pharmacology mechanism of NSAIDs. Our findings suggest that NSAIDs and Thal might prove useful to favor non-amyloidogenic APP processing by enhancing alpha-secretase activity, thereby reducing the formation of amyloidogenic derivatives, and therefore are of potential therapeutic value in AD.
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Affiliation(s)
- Yael Avramovich
- Eve Topf and National Parkinson Foundation Centers of Excellence for Neurodegenerative Diseases Research and Department of Pharmacology, Technion - Faculty of Medicine, 31096 Haifa, Israel
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Skovronsky DM, Lee VM, Praticò D. Amyloid precursor protein and amyloid beta peptide in human platelets. Role of cyclooxygenase and protein kinase C. J Biol Chem 2001; 276:17036-43. [PMID: 11278299 DOI: 10.1074/jbc.m006285200] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The main component of Alzheimer's disease (AD) senile plaques is amyloid-beta peptide (Abeta), a proteolytic fragment of the amyloid precursor protein (APP). Platelets contain both APP and Abeta and may contribute to the perivascular amyloid deposition seen in AD. However, no data are available concerning the biochemical mechanism(s) involved in their formation and release by these cells. We found that human platelets released APP and Abeta following activation with collagen or arachidonic acid. Inhibition of platelet cyclooxygenase (COX) reduced APP but not Abeta release following those stimuli. In contrast, activation of platelets by thrombin and calcium ionophore caused release of both APP and Abeta in a COX-independent fashion. Ex vivo studies showed that, despite suppression of COX activity, administration of aspirin did not modify Abeta or APP levels in serum or plasma, suggesting that this enzyme plays only a minor role in vivo. We examined the regulation of APP cleavage and release from activated platelets and found that cleavage requires protein kinase C (PKC) activity and is regulated by the intracellular second messengers phosphatidylinositol 2-phosphate and Ca(2+). Our data provide the first evidence that in human platelets COX is a minor component of APP secretion whereas PKC plays a major role in the secretory cleavage of APP. By contrast, Abeta release may represent secretion of preformed peptide and is totally independent of both COX and PKC activity.
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Affiliation(s)
- D M Skovronsky
- Center for Experimental Therapeutics and The Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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Sato K, Muroi M, Nakamura M, Fujimura M, Takatsuki A. Co-existing proteins interfere with the action of nordihydroguaiaretic acid on retrograde Golgi-to-ER protein trafficking in NRK cells and alpha-glucosidase reaction in vitro. Biosci Biotechnol Biochem 2001; 65:996-8. [PMID: 11388491 DOI: 10.1271/bbb.65.996] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Induction of retrograde trafficking of mannosidase II and TGN38 in NRK cells and inhibition of alpha-glucosidase in vitro by nordihydroguaiaretic acid (NDGA) were strongly interfered with by serum, serum albumin, or other unrelated proteins added to the medium or incubation mixture. These observations indicate that NDGA interacts with diverse kinds of proteins, and therefore, pharmacological effects of NDGA at cellular levels should be carefully interpreted.
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Affiliation(s)
- K Sato
- Animal and Cellular Systems Laboratory, RIKEN (The Institute of Physical and Chemical Research) Hirosawa, Wako-shi, Saitama, Japan
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Sugaya K, Uz T, Kumar V, Manev H. New anti-inflammatory treatment strategy in Alzheimer's disease. JAPANESE JOURNAL OF PHARMACOLOGY 2000; 82:85-94. [PMID: 10877525 DOI: 10.1254/jjp.82.85] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Numerous reports have indicated that patients suffering from inflammatory diseases (e.g., arthritis) who take anti-inflammatory medication have a reduced risk of developing Alzheimer's disease (AD). Thus, the first generation of anti-inflammatory cyclooxygenase (COX) inhibitors, such as aspirin and indomethacin, have been tested as potential therapeutics in AD. Because the inhibition of COX-1 is also known to cause tissue damage in the gastrointestinal system from the resultant reduced cytoprotection, selective COX-2 inhibitors are being investigated and tested clinically as potentially better therapeutics for AD patients. However, such drugs may also trigger unwanted effects; for example, the COX-2 inhibitors, which reduce the production of one type of eicosanoids, the prostaglandins, may increase the production of other eicosanoids; i.e., the leukotriene B4 (LTB4), which is one of the most potent endogenous chemotactic/inflammatory factors. LTB4 production is initiated by the enzyme 5-lipoxygenase (5-LOX). The expression of the 5-LOX gene is upregulated during neurodegeneration and with aging. In spite of the fact that 5-LOX and leukotrienes are major players in the inflammation cascade, their role in AD pathobiology/therapy has not been extensively investigated. We propose that the 5-LOX inflammatory cascade may take part in the process of aging-associated neurodegenerative diseases, and we point to the role of 5-LOX in neurodegeneration and discuss its relevance for anti-inflammatory therapy of AD.
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Affiliation(s)
- K Sugaya
- The Psychiatric Institute, West Side VA Medical Center, Department of Psychiatry, University of Illinois at Chicago, 60612, USA
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Abstract
Multiple lines of evidence suggest that increased production and/or deposition of the beta-amyloid peptide, derived from the amyloid precursor protein, contributes to Alzheimer's disease. A growing list of neurotransmitters, growth factors, cytokines, and hormones have been shown to regulate amyloid precursor protein processing. Although traditionally thought to be mediated by activation of protein kinase C, recent data have implicated other signaling mechanisms in the regulation of this process. Moreover, novel mechanisms of regulation involving cholesterol-, apolipoprotein E-, and stress-activated pathways have been identified. As the phenotypic changes associated with Alzheimer's disease encompass many of these signaling systems, it is relevant to determine how altered cell signaling may be contributing to increasing brain amyloid burden. We review the myriad ways in which first messengers regulate amyloid precursor protein catabolism as well as the signal transduction cascades that give rise to these effects.
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Affiliation(s)
- J Mills
- Kinsmen Laboratory of Neurological Research, Graduate Program in Neuroscience, University of British Columbia, Vancouver, Canada
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Licastro F, Davis LJ, Pedrini S, Galasko D, Masliah E. Prostaglandin E2 induced polymerization of human alpha-1-antichymotrypsin and suppressed its protease inhibitory activity: implications for Alzheimer's disease. Biochem Biophys Res Commun 1998; 249:182-6. [PMID: 9705853 DOI: 10.1006/bbrc.1998.9103] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Different molecular forms of alpha-1-antichymotrypsin (ACT) in sera and cerebrospinal fluids from patients with Alzheimer's disease (AD) were detected. Monomeric and polymeric ACT were observed by polyacrylamide gel electrophoresis of both sera and cerebrospinal fluids. ACT polymers were increased in AD patients with the apolipoprotein E (APOE) 4 allele. Increased levels of inactive ACT molecules were also detected in brain homogenates of patients with the APOE 4 allele. Experimental conditions promoting in vitro polymerization of ACT and the effect of polymerization on the biological activity of this serpin were also explored. Incubation of this serpin with prostaglandins of E series (PGE 2) induced ACT polymerization and decreased its activity. Amyloid beta-peptide1-42 did not significantly affected the biological activity of ACT. Inactivation of protease inhibitors by inflammatory molecules such as PGE 2 released from activated microglia in AD brains may promote amyloid deposition and neurodegeneration.
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Affiliation(s)
- F Licastro
- Dipartimento di Patologia Sperimentale, Università di Bologna, Italy
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Fujiwara T, Takami N, Misumi Y, Ikehara Y. Nordihydroguaiaretic acid blocks protein transport in the secretory pathway causing redistribution of Golgi proteins into the endoplasmic reticulum. J Biol Chem 1998; 273:3068-75. [PMID: 9446623 DOI: 10.1074/jbc.273.5.3068] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We have investigated the effect of nordihydroguaiaretic acid (NDGA), an inhibitor of lipoxygenase, on the intracellular protein transport and the structure of the Golgi complex. Pulse-chase experiments and immunoelectron microscopy showed that NDGA strongly inhibits the transport of newly synthesized secretory proteins to the Golgi complex resulting in their accumulation in the endoplasmic reticulum (ER). Despite their retention in the ER, oligosaccharides of secretory and ER-resident proteins were processed to endoglycosidase H-resistant forms, raising the possibility that oligosaccharide-processing enzymes are redistributed from the Golgi to the ER. Morphological observations further revealed that alpha-mannosidase II (a cis/medial-Golgi marker), but not TGN38 (a trans-Golgi network marker), rapidly redistributes to the ER in the presence of NDGA, resulting in the disappearance of the characteristic Golgi structure. Upon removal of the drug, the Golgi complex was reassembled into the normal structure as judged by perinuclear staining of alpha-mannosidase II and by restoration of the secretion. These effects of NDGA are quite similar to those of brefeldin A. However, unlike brefeldin A, NDGA did not cause a dissociation of beta-coatomer protein, a subunit of coatomer, from the Golgi membrane. On the contrary, NDGA exerted the stabilizing effect on beta-coatomer protein/membrane interaction against the dissociation caused by brefeldin A and ATP depletion. Taken together, these results indicate that NDGA is a potent agent disrupting the structure and function of the Golgi complex with a mechanism different from those known for other drugs reported so far.
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Affiliation(s)
- T Fujiwara
- Department of Biochemistry, Fukuoka University School of Medicine, Jonan-ku, Fukuoka 814-80, Japan
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Abstract
Proteolytic processing of beta-amyloid precursor protein (APP) is believed to be fundamental to the understanding of Alzheimer's disease. The identities and the regulatory elements of the proteases involved in the process, known as alpha/beta/gamma secretases, are unclear. In this study, by examining reported data, we found some indications suggesting that the putative alpha-secretase may be a calcium-dependent protease, and that this enzyme may play a primary role in the regulation of APP processing. Based on this, we proposed a model for the membrane orientations of the secretases for further discussions.
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Affiliation(s)
- M Chen
- Department of Pharmacology and Therapeutics, University of South Florida College of Medicine, Tampa 33612, USA.
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Smedman M, Potempska A, Rubenstein R, Ju W, Ramakrishna N, Denman RB. Effects of cadmium, copper, and zinc and beta APP processing and turnover in COS-7 and PC12 cells. Relationship to Alzheimer disease pathology. MOLECULAR AND CHEMICAL NEUROPATHOLOGY 1997; 31:13-28. [PMID: 9271002 DOI: 10.1007/bf02815157] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effects of cadmium, copper, and zinc on beta APP metabolism were investigated in COS-7 and PC12 cells. Cadmium chloride (CdCl2) increased beta APP steady-state protein levels and decreased beta APP posttranslational processing. These changes were not accompanied by alterations in beta APP mRNA levels or splicing. In addition, cytosolic alpha-actin and G3PDH levels were not affected. Further, neither zinc (ZnCl2) nor copper (CuSO4) altered beta APP levels or affected its normal processing. Pulse-chase studies revealed that the rate of beta APP maturation decreased twofold in the presence of 25 microM CdCl2 compared to untreated controls. beta APP secretion from the cell also dramatically slowed. These two factors result in the accumulation of partially processed beta APP inside cells. The presence of CdCl2 also decreased the amount of an 8-kDa beta APP C-terminal fragment, indicating that the cellular compartment in which beta APP accumulates is not accessible to alpha-secretase. Studies using Brefeldin A suggest that this compartment may be the cis or medial Golgi. However, A beta production was proportionately increased. These data show that CdCl2 can modulate the beta APP cleavage to favor A beta. Finally, beta APP mis- metabolism was shown to be unrelated to the hsp70 induction elicited by CdCl2; both heat shock and CuSO4 induced hsp70 but had no effect on steady-state levels of beta APP, although heat shock did slow beta APP maturation. These data indicate that hsp70 alone cannot chaperone beta APP through an alternate processing pathway leading to A beta production.
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Affiliation(s)
- M Smedman
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island 10314, USA
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Dayton ET, Major EO. Recombinant human interleukin 1 beta induces production of prostaglandins in primary human fetal astrocytes and immortalized human fetal astrocyte cultures. J Neuroimmunol 1996; 71:11-8. [PMID: 8982097 DOI: 10.1016/s0165-5728(96)00111-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Astrocytes play an important role in initiating and modulating inflammatory responses within the central nervous system. Extensive studies in rodents have shown that TPA, substance P, calcium ionophore A21387, and lipopolysaccharide (LPS) induce formation and release of arachidonic acid metabolites which have immunoregulatory properties. To better understand the immunopathology of brain injury, we studied the role of inflammatory cytokines such as tumor necrosis factor alpha, interleukin (IL) 6, IL-2, interferon gamma and IL-1 beta in the production of arachidonic acid metabolites in cells from fetal human brain. Among these cytokines, only IL-1 beta significantly stimulated production of prostaglandins E2 and F2 alpha but not PGD2, thromboxane B2 and 6-keto-PGF1 alpha. Under our experimental conditions, these astrocyte cultures did not produce metabolites in the lipoxygenase pathway such as leukotrienes B4 and C4 upon IL-1 beta stimulation. The stimulatory effects of IL-1 beta on the induction of arachidonic acid metabolites have been studied in various human cell types but not in astrocytes. Human astrocyte production of PGF2 alpha and PGE2 but not PGD2, 6-keto-PGF1 alpha and TXB2 when stimulated by IL-1 beta, is thus a novel finding. This observation should initiate investigations into the mechanism of arachidonic acid metabolism and the role of its metabolites in inflammation in the human nervous system.
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Affiliation(s)
- E T Dayton
- Laboratory of Molecular Medicine and Neuroscience, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892-4164, USA
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