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Yamashita A, Hayashi Y, Matsumoto N, Nemoto-Sasaki Y, Koizumi T, Inagaki Y, Oka S, Tanikawa T, Sugiura T. Coenzyme-A-Independent Transacylation System; Possible Involvement of Phospholipase A2 in Transacylation. BIOLOGY 2017; 6:biology6020023. [PMID: 28358327 PMCID: PMC5485470 DOI: 10.3390/biology6020023] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 03/23/2017] [Accepted: 03/24/2017] [Indexed: 11/29/2022]
Abstract
The coenzyme A (CoA)-independent transacylation system catalyzes fatty acid transfer from phospholipids to lysophospholipids in the absence of cofactors such as CoA. It prefers to use C20 and C22 polyunsaturated fatty acids such as arachidonic acid, which are esterified in the glycerophospholipid at the sn-2 position. This system can also acylate alkyl ether-linked lysophospholipids, is involved in the enrichment of arachidonic acid in alkyl ether-linked glycerophospholipids, and is critical for the metabolism of eicosanoids and platelet-activating factor. Despite their importance, the enzymes responsible for these reactions have yet to be identified. In this review, we describe the features of the Ca2+-independent, membrane-bound CoA-independent transacylation system and its selectivity for arachidonic acid. We also speculate on the involvement of phospholipase A2 in the CoA-independent transacylation reaction.
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Affiliation(s)
- Atsushi Yamashita
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Yasuhiro Hayashi
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Naoki Matsumoto
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Yoko Nemoto-Sasaki
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Takanori Koizumi
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Yusuke Inagaki
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Saori Oka
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Takashi Tanikawa
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Takayuki Sugiura
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
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Acyltransferases and transacylases that determine the fatty acid composition of glycerolipids and the metabolism of bioactive lipid mediators in mammalian cells and model organisms. Prog Lipid Res 2014; 53:18-81. [DOI: 10.1016/j.plipres.2013.10.001] [Citation(s) in RCA: 160] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 07/20/2013] [Accepted: 10/01/2013] [Indexed: 12/21/2022]
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Suckling K. Phospholipase A2s: Developing drug targets for atherosclerosis. Atherosclerosis 2010; 212:357-66. [DOI: 10.1016/j.atherosclerosis.2010.03.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 03/08/2010] [Accepted: 03/08/2010] [Indexed: 12/24/2022]
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Papamichael ND, Stathopoulou EM, Roussa VD, Tsironis LD, Kotsia AP, Stanica RM, Moussis V, Tsikaris V, Katsouras CS, Tselepis AD, Michalis LK. Effect of a Synthetic Peptide Corresponding to Residues 313 to 320 of the αIIbSubunit of the Human Platelet Integrin αIIbβ3on Carotid Artery Thrombosis in Rabbits. J Pharmacol Exp Ther 2009; 329:634-40. [DOI: 10.1124/jpet.108.150086] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Tsoukatos DC, Brochériou I, Moussis V, Panopoulou CP, Christofidou ED, Koussissis S, Sismanidis S, Ninio E, Siminelakis S. Platelet-activating factor acetylhydrolase and transacetylase activities in human aorta and mammary artery. J Lipid Res 2008; 49:2240-9. [PMID: 18587071 PMCID: PMC2533414 DOI: 10.1194/jlr.m800188-jlr200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Platelet-activating factor (PAF), the potent phospholipid mediator of inflammation, is involved in atherosclerosis. Platelet-activating factor-acetylhydrolase (PAF-AH), the enzyme that inactivates PAF bioactivity, possesses both acetylhydrolase and transacetylase activities. In the present study, we measured acetylhydrolase and transacetylase activities in human atherogenic aorta and nonatherogenic mammary arteries. Immunohistochemistry analysis showed PAF-AH expression in the intima and the media of the aorta and in the media of mammary arteries. Acetylhydrolase and transacetylase activities were (mean +/- SE, n = 38): acetylhydrolase of aorta, 2.8 +/- 0.5 pmol/min/mg of tissue; transacetylase of aorta, 3.3 +/- 0.7 pmol/min/mg of tissue; acetylhydrolase of mammary artery, 1.4 +/- 0.3 pmol/min/mg of tissue (P < 0.004 as compared with acetylhydrolase of aorta); transacetylase of mammary artery, 0.8 +/- 0.2 pmol/min/mg of tissue (P < 0.03 as compared with acetylhydrolase of mammary artery). Lyso-PAF accumulation and an increase in PAF bioactivity were observed in the aorta of some patients. Reverse-phase HPLC and electrospray ionization mass spectrometry analysis revealed that 1-O-hexadecyl-2 acetyl-sn glycero-3-phosphocholine accounted for 60% of the PAF bioactivity and 1-O-hexadecyl-2-butanoyl-sn-glycerol-3-phosphocholine for 40% of the PAF bioactivity. The nonatherogenic properties of mammary arteries may in part be due to low PAF formation regulated by PAF-AH activity. In atherogenic aortas, an imbalance between PAF-AH and transacetylase activity, as well as lyso-PAF accumulation, may lead to unregulated PAF formation and to progression of atherosclerosis.
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Maruyama C, Yoneyama M, Suyama N, Yoshimi K, Teramoto A, Sakaki Y, Suto Y, Takahashi K, Araki R, Ishizaka Y, Yamakado M, Teramoto T. Differences in Serum Phospholipid Fatty Acid Compositions and Estimated Desaturase Activities between Japanese Men with and without Metabolic Syndrome. J Atheroscler Thromb 2008; 15:306-13. [PMID: 19060426 DOI: 10.5551/jat.e564] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Chizuko Maruyama
- Department of Food and Nutrition, Faculty of Home Economics, Japan Women's University, Tokyo, Japan.
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Guerra CT, Caini P, Giannini C, Giannelli F, Gragnani L, Petrarca A, Solazzo V, Monti M, Laffi G, Zignego AL. Effect of chronic hepatitis C virus infection on inflammatory lipid mediators. Dig Liver Dis 2007; 39 Suppl 1:S76-82. [PMID: 17936229 DOI: 10.1016/s1590-8658(07)80016-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Platelet-activating factor (PAF), a powerful phospholipid mediator of inflammation, is degraded by plasma PAF-acetyl-hydxolase (pPAF-AH), an enzyme which circulates in serum mainly in a complex with lipoproteins that confer its biological activity. Hepatitis C virus (HCV) is linked to lipoproteins in serum too. Reduced pPAF-AH activity was observed in several diseases, including systemic vasculitis. AIM To evaluate if chronic HCV infection could alter pPAF-AH physiological functions. SUBJECTS 145 subjects were studied: 56 HCV- and 52 HBV-infected patients (pathologic controls); 37 healthy subjects (healthy controls). METHODS pPAF-AH activity, PAF and Apo B100 titers were determined in plasma; enzyme expression levels were evaluated in monocyte-derived macrophages. HCV-RNA was detected in plasma, peripheral blood mononuclear cells and liver samples. RESULTS HCV-infected patients showed an increase of PAF levels following a significant decrease of pPAF-AH activity. A recovery of pPAF-AH activity occurs only in patients who clear HCV after the antiviral treatment. Expression levels of pPAF-AH mRNA and Apo B100 titers were not modified in HCV patients in comparison to controls. CONCLUSION In light of these results, it is tempting to hypothesize that during chronic HCV infection, the PAF/pPAF-AH system may be altered and this condition may contribute to HCV-related vascular damage.
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Affiliation(s)
- Cristina Tosti Guerra
- Department of Internal Medicine, Center for the Study of Systemic Manifestations of Hepatitis Viruses MaSVE, University of Florence, Florence, Italy
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Kom GD, Schwedhelm E, Maas R, Schneider L, Benndorf R, Böger RH. Impact of atorvastatin treatment on platelet-activating factor acetylhydrolase and 15-F(2trans)-isoprostane in hypercholesterolaemic patients. Br J Clin Pharmacol 2007; 63:672-9. [PMID: 17214829 PMCID: PMC2000588 DOI: 10.1111/j.1365-2125.2006.02832.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
AIMS Isoprostanes are the product of free radical oxidation of arachidonic acid, whose hydrolysis from phospholipids is presumably catalysed by phospholipases A(2) (PLA(2)s) such as group IIA or V PLA(2)s, or group VII PLA(2)[platelet-activating factor acetylhydrolase (PAF-AH), lipoprotein-associated phospholipase]. Atorvastatin reduces concentrations of low-density lipoprotein (LDL), with which PAF-AH is associated, and PLA(2)s' protein concentrations. We investigated the effect of atorvastatin on PLA(2)s and PAF-AH activity and the urinary excretion of 15-F(2trans)-isoprostane (15-F(2t)-IsoP, 8-iso-PGF(2alpha), iPF(2alpha)-III). METHODS Twenty-four hypercholesterolaemic individuals naive to lipid-lowering therapy were randomized to atorvastatin 40 mg or placebo for 6 weeks. The 15-F(2t)-isoP urinary excretion (gas chromatography/mass spectrometry), PAF-AH and group IIA and V PLA(2) activities (photometry) were assessed at baseline and end-point. RESULTS At end-point, 15-F(2t)-isoP urinary excretion concentrations as well as PLA(2)s' activity were unchanged under atorvastatin (mean change 0.21 +/- 1.79 ng h(-1), 95% confidence interval -0.92, 1.35 and 0.33 +/- 0.94 nmol min(-1) ml(-1), -0.27, 0.93) and under placebo (mean change 0.69 +/- 1.69 ng h(-1), -0.52, 1.90 and 1.29 +/- 2.16 nmol min(-1) ml(-1), -0.25, 2.84). Atorvastatin treatment decreased total (P < 0.001) and LDL-cholesterol (P < 0.001) but had no effect on high-density lipoprotein. PAF-AH activity was lowered in the atorvastatin group (mean change - 5.27+/- 1.96 nmol min(-1) ml(-1), -6.51, -4.03, P < 0.001) but not in the placebo group (mean change 1.02 +/- 1.64 nmol min(-1) ml(-1), 0.15, 2.20), and the change in PAF-AH activity was correlated with that in total (P = 0.03) and LDL-cholesterol (P = 0.03). CONCLUSION Our results show a lowering effect of atorvastatin on PAF-AH activity associated with its lipid-lowering effect and exclude a key role of PAF-AH in the liberation of 15-F(2t)-isoP from phospholipids.
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Affiliation(s)
- Ghainsom D Kom
- Institute of Experimental and Clinical Pharmacology and Toxicology, University Medical Centre Hamburg--Eppendorf, Hamburg, Germany.
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Caini P, Guerra CT, Giannini C, Giannelli F, Gragnani L, Petrarca A, Solazzo V, Monti M, Laffi G, Zignego AL. Modifications of plasma platelet-activating factor (PAF)-acetylhydrolase/PAF system activity in patients with chronic hepatitis C virus infection. J Viral Hepat 2007; 14:22-8. [PMID: 17212640 DOI: 10.1111/j.1365-2893.2006.00766.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Hepatitis C virus (HCV) chronically infects about 200 million individuals worldwide and leads to severe liver and lymphatic diseases. HCV circulates in the serum, associated with apoB-containing lipoproteins. Platelet-activating factor (PAF), a pro-inflammatory mediator, is mainly modulated by plasma PAF-acetylhydrolase (pPAF-AH), associated with ApoB100-containing low-density lipoproteins (LDL). The aim of the study was to evaluate the potential effects of chronic HCV infection on the PAF/pPAF-AH system. HCV-RNA was detected in plasma, peripheral blood mononuclear cells (PBMC) and liver samples. Plasma PAF levels, pPAF-AH activity, ApoB100 serum titres and pPAF-AH mRNA levels in cultured macrophages were determined. Plasma PAF levels were significantly higher and pPAF-AH activity was significantly lower in HCV patients than in controls. No significant modifications of pPAF-AH mRNA in macrophages or in ApoB100 values were observed in HCV patients compared with controls. Patients who cleared HCV after antiviral treatment showed a complete restoration of pPAF-AH activity and significant decrease of PAF levels during the follow-up. No data exist about the PAF/pPAF-AH system behaviour during HCV infection. This study shows that in HCV patients modifications of pPAF-AH activity/PAF levels take place and that HCV clearance restored pPAF-AH activity. This suggests that circulating viral particles play a role in PAF/pPAF-AH system modifications and such an alteration could be involved in HCV-related damage.
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Affiliation(s)
- P Caini
- Department of Internal Medicine, Center for the Study of Systemic Manifestations of Hepatitis Viruses MASVE and Higher Education Research and Transfer Center DENOTHE, University of Florence, Florence, Italy
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Beaudeux JL, Said T, Ninio E, Ganné F, Soria J, Delattre J, Soria C, Legrand A, Peynet J. Activation of PAF receptor by oxidised LDL in human monocytes stimulates chemokine releases but not urokinase-type plasminogen activator expression. Clin Chim Acta 2005; 344:163-71. [PMID: 15149885 DOI: 10.1016/j.cccn.2004.02.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2004] [Revised: 02/05/2004] [Accepted: 02/23/2004] [Indexed: 01/30/2023]
Abstract
BACKGROUND We investigated whether the increase of urokinase-type plasminogen activator (uPA) monocyte expression and chemokine releases induced by oxidised low density lipoproteins (LDL), which participate to vascular tissue remodeling and to atherosclerotic plaque rupture, involved proinflammatory phospholipid products having platelet-activating factor (PAF)-like activity via the PAF-receptor pathway. METHODS uPA monocyte expression was stimulated by either copper ions-oxidised or O2*-/HO* free radical-oxidised LDL. The effects of PAF and oxidised LDL on the production of monocyte chemoattractant protein-1 and interleukin-8 were also examined. RESULTS Synthetic PAF significantly enhanced chemokine releases (P<0.001) without modifying uPA expression. Copper-oxidised LDL, which exhibit a higher content in lysophosphatidylcholines than free radical-oxidised LDL, induced a significantly higher enhancement in uPA expression (P<0.05). By contrast, free radical-oxidised LDL were more efficient than copper-oxidised LDL to increase chemokine releases (P<0.01). Oxidised LDL-enhanced uPA expressions were not altered by the PAF-receptor antagonist SR27417, whereas increases in chemokine releases induced by oxidised LDL and by PAF were abolished. PAF-acetylhydrolase activity was rapidly and largely inhibited in free radical-oxidised LDL when compared to copper-oxidised LDL, suggesting that free radical-oxidised LDL would contain a higher content in PAF-like products than copper-oxidised LDL. CONCLUSION Our results indicated that PAF-like oxidation products are responsible for the monocyte chemokine releases, but did not contribute to the enhanced monocyte uPA expression by oxidised LDL.
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Affiliation(s)
- Jean-Louis Beaudeux
- Laboratoire de Biochimie, EA 3617, Faculté des Sciences Pharmaceutiques et Biologiques, 4, avenue de l'Observatoire, 75006 Paris, France.
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Karasawa K, Harada A, Satoh N, Inoue K, Setaka M. Plasma platelet activating factor-acetylhydrolase (PAF-AH). Prog Lipid Res 2003; 42:93-114. [PMID: 12547653 DOI: 10.1016/s0163-7827(02)00049-8] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The platelet-activating factor-acetylhydrolase (PAF-AH) is an enzyme which catalyzes the hydrolysis of acetyl ester at the sn-2 position of PAF. The family of PAF-AHs consists of two intracellular isoforms (Ib and II), and one secreted isoform (plasma). These PAF-AHs show different biochemical characteristics and molecular structures. Plasma PAF-AH and intracellular isoform, II degrade not only PAF but also oxidatively fragmented phospholipids with potent biological activities. Among these PAF-AHs, plasma PAF-AH has been the target of many clinical studies in inflammatory diseases, such as asthma, sepsis, and vascular diseases, because the plasma PAF-AH activity in the patients with these diseases is altered when compared with normal individuals. Finding a genetic deficiency in the plasma PAF-AH opened the gate in elucidating the protecting role of this enzyme in inflammatory diseases. The most common loss-of-function mutation, V279F, is found in more than 30% of Japanese subjects (4% homozygous, 27% heterozygous). This single nucleotide polymorphism in plasma PAF-AH and the resulting enzymatic deficiency is thought to be a genetic risk factor in various inflammatory diseases in Japanese subjects. Administration of recombinant plasma PAF-AH or transfer of the plasma PAF-AH gene improves pathology in animal models. Therefore, substitution of plasma PAF-AH would be an effective in the treatment of the patients with the inflammatory diseases and a novel clinical approach. In addition, the detection of polymorphisms in the plasma PAF-AH gene and abnormalities in enzyme activity would be beneficial in the diagnosis of the inflammatory diseases.
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Affiliation(s)
- Ken Karasawa
- Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko, Kanagawa, Japan.
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Tselepis AD, John Chapman M. Inflammation, bioactive lipids and atherosclerosis: potential roles of a lipoprotein-associated phospholipase A2, platelet activating factor-acetylhydrolase. ATHEROSCLEROSIS SUPP 2002; 3:57-68. [PMID: 12573364 DOI: 10.1016/s1567-5688(02)00045-4] [Citation(s) in RCA: 229] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
It is well established that inflammation is an integral feature of atherosclerosis and of the cardiovascular diseases which it underlies. Oxidative stress is also recognized as a key actor in atherogenesis, in which it is closely associated with the inflammatory response and bioactive lipid formation. Several bioactive lipids have been identified in the atherosclerotic plaque, including the potent inflammatory mediator platelet activating factor (PAF), PAF-like lipids, oxidised phospholipids (oxPL) and lysophosphatidylcholine (lyso-PC). Recent evidence has established a central role of two phospholipases (PL) in atherogenesis, the non-pancreatic Type II secretory phospholipase A(2) (sPLA(2)) and the lipoprotein-associated PLA(2)-alternatively termed as PAF-acetylhydrolase (PAF-AH). sPLA(2) is calcium-dependent and hydrolyses the sn-2 acyl group of glycerophospholipids of lipoproteins and cell membranes to produce lyso-PC and free fatty acids. It is also implicated in isoprostane production from oxPL. sPLA(2) is an acute phase reactant, which is upregulated by inflammatory cytokines and may represent a new independent risk factor for coronary heart disease. In contrast to sPLA(2), PAF-AH is calcium-independent and is specific for short acyl groups at the sn-2 position of the phospholipid substrate and with the exception of PAF, can equally hydrolyze oxPL to generate lyso-PC and oxidized fatty acids. Thus PAF-AH plays a key role in the degradation of proinflammatory oxPL and in the generation of lyso-PC and oxidized fatty acids. PAF-AH equally can also hydrolyze short-chain diacylglycerols, triacylglycerols, and acetylated alkanols, and displays a PLA(1) activity. Whereas sPLA(2) may represent a new independent risk factor for coronary artery disease, the potential relevance of PAF-AH to atherosclerosis remains the subject of debate, and recent results suggest that the potential role of the LDL-associated PAF-AH in atherogenesis may be distinct to that of the HDL-associated enzyme. This review is focused on the main structural and catalytic features of plasma PAF-AH, on the association of the enzyme with distinct lipoprotein particle subspecies, on its cellular sources, and finally on the potential significance of this lipoprotein-associated PLA(2) in cardiovascular disease.
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Wen T, Gu P, Minning TA, Wu Q, Liu M, Chen F, Liu H, Huang H. Microarray analysis of neural stem cell differentiation in the striatum of the fetal rat. Cell Mol Neurobiol 2002; 22:407-16. [PMID: 12507390 DOI: 10.1023/a:1021059520618] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
1. Gene expression profiles in neural stem cell differentiation in vitro were determined by cDNA microarray analysis. 2. Total RNA was extracted and reverse transcripted into cDNA from differentiated and undifferentiated neural stem cells. The 33P labeled cDNA was hybridized with a cDNA microarray consisting of 14,000 human genes. 3. The results showed that a total of 1406 genes were differentially expressed, of which 148 genes exhibited more than twofold differences. Some genes were obviously activated while others were strongly repressed. These changes in gene expression suggest that differentiation is regulated by different genes at different expressional levels. By biological classification, the differentially expressed genes were divided into four functional categories: molecular function, biological process, cellular component, and new functional genes or ESTs. 4. These findings will be a valuable contribution for gene expression profiling and elucidation of neural stem cell differentiation mechanisms.
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Affiliation(s)
- Tieqiao Wen
- Laboratory of Neural Molecular Biology, School of Life Sciences, Shanghai University, 99 Shangda Road, Shanghai 200436, People's Republic of China.
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