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Hussein MM, Fouda EM, Shehab Y, Nabih ES, Osman AM, Ishak SR. Association between arachidonate lipoxygenase 15,c.-292 C > T gene polymorphism and non-cystic fibrosis bronchiectasis in children: a pilot study on the effects on airway lipoxin A4 and disease phenotype. Ital J Pediatr 2024; 50:90. [PMID: 38685084 PMCID: PMC11059722 DOI: 10.1186/s13052-024-01654-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 04/07/2024] [Indexed: 05/02/2024] Open
Abstract
BACKGROUND Persistent airway inflammation is a central feature of bronchiectasis. Arachidonate 15-lipoxygenase (ALOX-15) controls production of endogenous lipid mediators, including lipoxins that regulate airway inflammation. Mutations at various positions in ALOX-15 gene can influence airway disease development. We investigated association between ALOX-15,c.-292 C > T gene polymorphism and bronchiectasis unrelated to cystic fibrosis in Egyptian children. Also, lipoxin A4 (LXA4) level in bronchoalveolar lavage (BAL) was studied in relation to polymorphism genotypes and disease phenotypes determined by clinical, pulmonary functions, and radiological severity parameters. METHODS This was an exploratory study that included 60 participants. Thirty children with non-cystic fibrosis bronchiectasis (NCFB) were compared with 30 age and sex-matched controls. ALOX-15,c.-292 C > T polymorphism was genotyped using TaqMan-based Real-time PCR. LXA4 was measured in BAL using ELISA method. RESULTS There was no significant difference between patients and controls regarding ALOX-15,c.-292 C > T polymorphism genotypes and alleles (OR = 1.75; 95% CI (0.53-5.7), P = 0.35) (OR = 1; 95% CI (0.48-2), p = 1). BAL LXA4 level was significantly lower in patients, median (IQR) of 576.9 (147.6-1510) ng/ml compared to controls, median (IQR) of 1675 (536.8-2542) (p = 0.002). Patients with severe bronchiectasis had a significantly lower LXA4 level (p < 0.001). There were significant correlations with exacerbations frequency (r=-0.54, p = 0.002) and FEV1% predicted (r = 0.64, p = 0.001). Heterozygous CT genotype carriers showed higher LXA4 levels compared to other genotypes(p = 0.005). CONCLUSIONS Low airway LXA4 in children with NCFB is associated with severe disease phenotype and lung function deterioration. CT genotype of ALOX-15,c.-292 C > T polymorphism might be a protective genetic factor against bronchiectasis development and/or progression due to enhanced LXA4 production.
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Affiliation(s)
| | - Eman Mahmoud Fouda
- Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Yasmine Shehab
- Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Enas Samir Nabih
- Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Ahmed Mohamed Osman
- Radiology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Sally Raafat Ishak
- Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
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2
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Zhou J, Zhou H, Liu Y, Liu C. Inhibition of CTCF-regulated miRNA-185-5p mitigates renal interstitial fibrosis of chronic kidney disease. Epigenomics 2021; 13:859-873. [PMID: 33977784 DOI: 10.2217/epi-2020-0243] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Aim: The present study aimed to elucidate the effect of CTCF on renal interstitial fibrosis in chronic kidney disease (CKD) and underlying mechanisms. Materials & methods: We measured NPHS2 expression and investigated its function in a unilateral ureteral obstruction-induced mouse model of CKD. Results: NPHS2 was poorly expressed in CKD mice. miR-185-5p targeted NPHS2 and reduced its expression, leading to increased α-SMA and COL I/III expression, increased renal interstitial fibrosis area and elevated phosphorylated vasodilator-stimulated phosphoprotein/vasodilator-stimulated phosphoprotein ratio. Co-treatment with CTCF downregulated miR-185-5p expression and abolished its effects in the CKD model. Conclusion: CTCF suppressed miR-185-5p and upregulated its target NPHS2, with a net effect of alleviating renal interstitial fibrosis in CKD.
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Affiliation(s)
- Jiajun Zhou
- Kidney Department, Yijishan Hospital of Wannan Medical College, Wuhu 241001, PR China
| | - Han Zhou
- Queen Mary College of Nanchang University, Nanchang 330031, PR China
| | - Yong Liu
- Kidney Department, Yijishan Hospital of Wannan Medical College, Wuhu 241001, PR China
| | - Caixin Liu
- Clinical Laboratory, Yijishan Hospital of Wannan Medical College, Wuhu 241001, PR China
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3
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MicroRNAs in shaping the resolution phase of inflammation. Semin Cell Dev Biol 2021; 124:48-62. [PMID: 33934990 DOI: 10.1016/j.semcdb.2021.03.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 03/28/2021] [Accepted: 03/29/2021] [Indexed: 12/19/2022]
Abstract
Inflammation is a host defense mechanism orchestrated through imperative factors - acute inflammatory responses mediated by cellular and molecular events leading to activation of defensive immune subsets - to marginalize detrimental injury, pathogenic agents and infected cells. These potent inflammatory events, if uncontrolled, may cause tissue damage by perturbing homeostasis towards immune dysregulation. A parallel host mechanism operates to contain inflammatory pathways and facilitate tissue regeneration. Thus, resolution of inflammation is an effective moratorium on the pro-inflammatory pathway to avoid the tissue damage inside the host and leads to reestablishment of tissue homeostasis. Dysregulation of the resolution pathway can have a detrimental impact on tissue functionality and contribute to the diseased state. Multiple reports have suggested peculiar dynamics of miRNA expression during various pro- and anti-inflammatory events. The roles of miRNAs in the regulation of immune responses are well-established. However, understanding of miRNA regulation of the resolution phase of events in infection or wound healing models, which is sometimes misconstrued as anti-inflammatory signaling, remains limited. Due to the deterministic role of miRNAs in pro-inflammatory and anti-inflammatory pathways, in this review we have provided a broad perspective on the putative role of miRNAs in the resolution of inflammation and explored their imminent role in therapeutics.
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4
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Andrews D, Godson C. Lipoxins and synthetic lipoxin mimetics: Therapeutic potential in renal diseases. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158940. [PMID: 33839296 DOI: 10.1016/j.bbalip.2021.158940] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 12/26/2022]
Abstract
Inflammation and its timely resolution are critical to ensuring effective host defence and appropriate tissue repair after injury. Unresolved inflammation typifies many renal pathologies. The key drivers of the inflammatory response are well defined and targeted by conventional anti-inflammatory therapeutics. However, these are associated with undesirable side effects including immune suppression. More recently, there is growing appreciation that specialized lipid mediators [SPMs] including lipoxins promote the resolution of inflammation and endogenous repair mechanisms without compromising host defence. We discuss the pro-resolving bioactions of lipoxins and recent work that aims to harness their therapeutic potential in the context of kidney disease.
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Affiliation(s)
- Darrell Andrews
- Diabetes Complications Research Centre, Conway Institute and School of Medicine, University College Dublin, Dublin, Ireland
| | - Catherine Godson
- Diabetes Complications Research Centre, Conway Institute and School of Medicine, University College Dublin, Dublin, Ireland.
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5
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Arachidonic Acid Metabolism and Kidney Inflammation. Int J Mol Sci 2019; 20:ijms20153683. [PMID: 31357612 PMCID: PMC6695795 DOI: 10.3390/ijms20153683] [Citation(s) in RCA: 163] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/19/2019] [Accepted: 07/20/2019] [Indexed: 12/17/2022] Open
Abstract
As a major component of cell membrane lipids, Arachidonic acid (AA), being a major component of the cell membrane lipid content, is mainly metabolized by three kinds of enzymes: cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome P450 (CYP450) enzymes. Based on these three metabolic pathways, AA could be converted into various metabolites that trigger different inflammatory responses. In the kidney, prostaglandins (PG), thromboxane (Tx), leukotrienes (LTs) and hydroxyeicosatetraenoic acids (HETEs) are the major metabolites generated from AA. An increased level of prostaglandins (PGs), TxA2 and leukotriene B4 (LTB4) results in inflammatory damage to the kidney. Moreover, the LTB4-leukotriene B4 receptor 1 (BLT1) axis participates in the acute kidney injury via mediating the recruitment of renal neutrophils. In addition, AA can regulate renal ion transport through 19-hydroxystilbenetetraenoic acid (19-HETE) and 20-HETE, both of which are produced by cytochrome P450 monooxygenase. Epoxyeicosatrienoic acids (EETs) generated by the CYP450 enzyme also plays a paramount role in the kidney damage during the inflammation process. For example, 14 and 15-EET mitigated ischemia/reperfusion-caused renal tubular epithelial cell damage. Many drug candidates that target the AA metabolism pathways are being developed to treat kidney inflammation. These observations support an extraordinary interest in a wide range of studies on drug interventions aiming to control AA metabolism and kidney inflammation.
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6
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Gilroy DW, Bishop-Bailey D. Lipid mediators in immune regulation and resolution. Br J Pharmacol 2019; 176:1009-1023. [PMID: 30674066 DOI: 10.1111/bph.14587] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 12/05/2018] [Accepted: 12/08/2018] [Indexed: 12/31/2022] Open
Abstract
We are all too familiar with the events that follow a bee sting-heat, redness, swelling, and pain. These are Celsus' four cardinal signs of inflammation that are driven by very well-defined signals and hormones. In fact, targeting the factors that drive this onset phase is the basis upon which most current anti-inflammatory therapies were developed. We are also very well aware that within a few hours, these cardinal signs normally disappear. In other words, inflammation resolves. When it does not, inflammation persists, resulting in damaging chronic conditions. While inflammatory onset is actively driven, so also is its resolution-years of research have identified novel internal counter-regulatory signals that work together to switch off inflammation. Among these signals, lipids are potent signalling molecules that regulate an array of immune responses including vascular hyper reactivity and pain, as well as leukocyte trafficking and clearance, so-called resolution. Here, we collate bioactive lipid research to date and summarize the major pathways involved in their biosynthesis and their role in inflammation, as well as resolution. LINKED ARTICLES: This article is part of a themed section on Eicosanoids 35 years from the 1982 Nobel: where are we now? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.8/issuetoc.
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Affiliation(s)
- Derek W Gilroy
- Centre for Clinical Pharmacology and Therapeutics, Division of Medicine, University College London, London, UK
| | - David Bishop-Bailey
- Comparative Biological Sciences, Royal Veterinary College, University of London, London, UK
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7
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Singh NK, Rao GN. Emerging role of 12/15-Lipoxygenase (ALOX15) in human pathologies. Prog Lipid Res 2019; 73:28-45. [PMID: 30472260 PMCID: PMC6338518 DOI: 10.1016/j.plipres.2018.11.001] [Citation(s) in RCA: 162] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 11/07/2018] [Accepted: 11/09/2018] [Indexed: 02/06/2023]
Abstract
12/15-lipoxygenase (12/15-LOX) is an enzyme, which oxidizes polyunsaturated fatty acids, particularly omega-6 and -3 fatty acids, to generate a number of bioactive lipid metabolites. A large number of studies have revealed the importance of 12/15-LOX role in oxidative and inflammatory responses. The in vitro studies have demonstrated the ability of 12/15-LOX metabolites in the expression of various genes and production of cytokine related to inflammation and resolution of inflammation. The studies with the use of knockout and transgenic animals for 12/15-LOX have further shown its involvement in the pathogenesis of a variety of human diseases, including cardiovascular, renal, neurological and metabolic disorders. This review summarizes our current knowledge on the role of 12/15-LOX in inflammation and various human diseases.
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Affiliation(s)
- Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street Memphis, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street Memphis, Memphis, TN 38163, USA.
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8
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Çolakoğlu M, Tunçer S, Banerjee S. Emerging cellular functions of the lipid metabolizing enzyme 15-Lipoxygenase-1. Cell Prolif 2018; 51:e12472. [PMID: 30062726 DOI: 10.1111/cpr.12472] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 04/22/2018] [Indexed: 02/06/2023] Open
Abstract
The oxygenation of polyunsaturated fatty acids such as arachidonic and linoleic acid through lipoxygenases (LOXs) and cyclooxygenases (COXs) leads to the production of bioactive lipids that are important both in the induction of acute inflammation and its resolution. Amongst the several isoforms of LOX that are expressed in mammals, 15-LOX-1 was shown to be important both in the context of inflammation, being expressed in cells of the immune system, and in epithelial cells where the enzyme has been shown to crosstalk with a number of important signalling pathways. This review looks into the latest developments in understanding the role of 15-LOX-1 in different disease states with emphasis on the emerging role of the enzyme in the tumour microenvironment as well as a newly re-discovered form of cell death called ferroptosis. We also discuss future perspectives on the feasibility of use of this protein as a target for therapeutic interventions.
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Affiliation(s)
- Melis Çolakoğlu
- Department of Biological Sciences, Middle East Technical University, Ankara, Turkey
| | - Sinem Tunçer
- Department of Biological Sciences, Middle East Technical University, Ankara, Turkey
| | - Sreeparna Banerjee
- Department of Biological Sciences, Middle East Technical University, Ankara, Turkey
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9
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Kroschwald S, Chiu CY, Heydeck D, Rohwer N, Gehring T, Seifert U, Lux A, Rothe M, Weylandt KH, Kuhn H. Female mice carrying a defective Alox15 gene are protected from experimental colitis via sustained maintenance of the intestinal epithelial barrier function. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:866-880. [PMID: 29702245 DOI: 10.1016/j.bbalip.2018.04.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 04/17/2018] [Accepted: 04/21/2018] [Indexed: 12/19/2022]
Abstract
Lipoxygenases (ALOXs) are involved in the regulation of cellular redox homeostasis. They also have been implicated in the biosynthesis of pro- and anti-inflammatory lipid mediators and play a role in the pathogenesis of inflammatory diseases, which constitute a major health challenge owing to increasing incidence and prevalence in all industrialized countries around the world. To explore the pathophysiological role of Alox15 (leukocyte-type 12-LOX) in mouse experimental colitis we tested the impact of systemic inactivation of the Alox15 gene on the extent of dextrane sulfate sodium (DSS) colitis. We found that in wildtype mice expression of the Alox15 gene was augmented during DSS-colitis while expression of other Alox genes (Alox5, Alox15b) was hardly altered. Systemic Alox15 (leukocyte-type 12-LOX) deficiency induced less severe colitis symptoms and suppressed in vivo formation of 12-hydroxyeicosatetraenoic acid (12-HETE), the major Alox15 (leukocyte-type 12-LOX) product in mice. These alterations were paralleled by reduced expression of pro-inflammatory gene products, by sustained expression of the zonula occludens protein 1 (ZO-1) and by a less impaired intestinal epithelial barrier function. These results are consistent with in vitro incubations of colon epithelial cells, in which addition of 12S-HETE compromised enantioselectively transepithelial electric resistance. Consistent with these data transgenic overexpression of human ALOX15 intensified the inflammatory symptoms. In summary, our results indicate that systemic Alox15 (leukocyte-type 12-LOX) deficiency protects mice from DSS-colitis. Since exogenous 12-HETE compromises the expression of the tight junction protein ZO-1 the protective effect has been related to a less pronounced impairment of the intestinal epithelial barrier function.
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Affiliation(s)
- Saskia Kroschwald
- Institute of Biochemistry, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Chariteplatz 1, D-10117 Berlin, Germany; Institute for Molecular and Clinical Immunology, Medical Faculty of the Otto-von-Guericke-University, Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Cheng-Ying Chiu
- Division of Medicine, Department of Hepatology, Gastroenterology and Metabolism, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Dagmar Heydeck
- Institute of Biochemistry, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Chariteplatz 1, D-10117 Berlin, Germany
| | - Nadine Rohwer
- Division of Medicine, Department of Hepatology, Gastroenterology and Metabolism, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Tatjana Gehring
- Institute of Biochemistry, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Chariteplatz 1, D-10117 Berlin, Germany
| | - Ulrike Seifert
- Institute for Molecular and Clinical Immunology, Medical Faculty of the Otto-von-Guericke-University, Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Anke Lux
- Institute for Molecular and Clinical Immunology, Medical Faculty of the Otto-von-Guericke-University, Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Michael Rothe
- Lipidomix GmbH, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Karsten-Henrich Weylandt
- Division of Medicine, Department of Hepatology, Gastroenterology and Metabolism, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Augustenburger Platz 1, 13353 Berlin, Germany; Division of Medicine, Department of Gastroenterology and Oncology, Ruppiner Kliniken, Brandenburg Medical School, 16816 Neuruppin, Germany.
| | - Hartmut Kuhn
- Institute of Biochemistry, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Chariteplatz 1, D-10117 Berlin, Germany.
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10
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Abstract
Lipids are potent signaling molecules that regulate a multitude of cellular responses, including cell growth and death and inflammation/infection, via receptor-mediated pathways. Derived from polyunsaturated fatty acids (PUFAs), such as arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), each lipid displays unique properties, thus making their role in inflammation distinct from that of other lipids derived from the same PUFA. This diversity arises from their synthesis, which occurs via discrete enzymatic pathways and because they elicit responses via different receptors. This review will collate the bioactive lipid research to date and summarize the major pathways involved in their biosynthesis and role in inflammation. Specifically, lipids derived from AA (prostanoids, leukotrienes, 5-oxo-6,8,11,14-eicosatetraenoic acid, lipoxins, and epoxyeicosatrienoic acids), EPA (E-series resolvins), and DHA (D-series resolvins, protectins, and maresins) will be discussed herein.
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11
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Possible involvement of the lipoxygenase and leukotriene signaling pathways in cisplatin-mediated renal toxicity. Cancer Chemother Pharmacol 2017; 80:55-64. [DOI: 10.1007/s00280-017-3331-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 05/02/2017] [Indexed: 01/18/2023]
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Tarannum F, Faizuddin M. Effect of Alox-15 Polymorphism on GCF Levels of Lipoxin-A4 in Chronic Periodontitis: A Preliminary Study. Braz Dent J 2017; 28:140-147. [DOI: 10.1590/0103-6440201701094] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 01/04/2017] [Indexed: 12/12/2022] Open
Abstract
Lipoxins play an important role in periodontal resolution, hence, investigation of genetic polymorphism of lipoxin gene may provide important information on the role of lipoxins in periodontal disease pathogenesis. The aim of this study was to investigate a polymorphism of C-to-T substitution at position c.-292 in ALOX15 (reticulocyte-type 15 lipoxygenase 1) gene in patients with chronic periodontitis and to associate the polymorphism with gingival crevicular fluid (GCF) lipoxin A4 (LXA4) levels. Forty-five chronic periodontitis and 45 periodontally healthy patients were included in this case-control study. Plaque index, calculus index, sulcus bleeding index, full mouth probing depth (PD) and clinical attachment loss (CAL) were recorded. GCF and blood samples were collected. GCF was analyzed for LXA4 levels by enzyme linked immunosorbant assay. Genotyping of ALOX15 polymorphism was studied using PCR. Mean LXA4 was lower in periodontitis group compared to the periodontally healthy group. There was a negative correlation between CAL and LXA4. The CC genotype was higher in the study group than in the control group. In the study group, mean CAL was significantly lower among individuals with the CT genotype. Mean LXA4 was significantly lower in CC genotype (45.0±7.11 ng/mL) compared to CT genotype (50.81±5.81 ng/mL) among the patients with periodontitis. The results suggest that LXA4 and c.-292T allele are associated with periodontal health. Polymorphisms in the ALOX15 gene may influence periodontal disease pathogenesis. Hence, investigation of such polymorphisms could benefit the evaluation of lipoxins role in periodontal disease.
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Abstract
The clinical category of acute kidney injury includes a wide range of completely different disorders, many with their own pathomechanisms and treatment targets. In this review we focus on the role of inflammation in the pathogenesis of acute tubular necrosis (ATN). We approach this topic by first discussing the role of the immune system in the different phases of ATN (ie, early and late injury phase, recovery phase, and the long-term outcome phase of an ATN episode). A more detailed discussion focuses on putative therapeutic targets among the following mechanisms and mediators: oxidative stress and reactive oxygen species-related necroinflammation, regulated cell death-related necroinflammation, immunoregulatory lipid mediators, cytokines and cytokine signaling, chemokines and chemokine signaling, neutrophils and neutrophils extracellular traps (NETs) associated neutrophil cell death, called NETosis, extracellular histones, proinflammatory mononuclear phagocytes, humoral mediators such as complement, pentraxins, and natural antibodies. Any prioritization of these targets has to take into account the intrinsic differences between rodent models and human ATN, the current acute kidney injury definitions, and the timing of clinical decision making. Several conceptual problems need to be solved before anti-inflammatory drugs that are efficacious in rodent ATN may become useful therapeutics for human ATN.
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Affiliation(s)
- Shrikant R Mulay
- Nephrologisches Zentrum, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Alexander Holderied
- Nephrologisches Zentrum, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Santhosh V Kumar
- Nephrologisches Zentrum, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Hans-Joachim Anders
- Nephrologisches Zentrum, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany.
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14
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Tian R, Zuo X, Jaoude J, Mao F, Colby J, Shureiqi I. ALOX15 as a suppressor of inflammation and cancer: Lost in the link. Prostaglandins Other Lipid Mediat 2017; 132:77-83. [PMID: 28089732 DOI: 10.1016/j.prostaglandins.2017.01.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 01/06/2017] [Accepted: 01/09/2017] [Indexed: 02/06/2023]
Abstract
Mounting evidence supports a mechanistic link between inflammation and cancer, especially colon cancer. ALOX15 (15-lipoxygenase-1) plays an important role in the formation of key lipid mediators (e.g., lipoxins and resolvins) to terminate inflammation. ALOX15 expression is downregulated in colorectal cancer (CRC). Intestinally-targeted transgenic expression of ALOX15 in mice inhibited dextran sodium sulfate-induced colitis from promoting azoxymethane- induced colorectal tumorigenesis, demonstrating that ALOX15 can suppress inflammation-driven promotion of carcinogen-induced colorectal tumorigenesis and therefore ALOX15 downregulation during tumorigenesis is likely to enhance the link between colitis and colorectal tumorigenesis. ALOX15 suppressed the TNF-α, IL-1β/NF-κB, and IL-6/STAT3 signaling pathways, which play major roles in promotion of colorectal cancer by chronic inflammation. Defining ALOX15's regulatory role in colitis-associated colorectal cancer could identify important molecular regulatory events that could be targeted to suppress promotion of tumorigenesis by chronic inflammation.
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Affiliation(s)
- Rui Tian
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States
| | - Xiangsheng Zuo
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States
| | - Jonathan Jaoude
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States
| | - Fei Mao
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States
| | - Jennifer Colby
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States
| | - Imad Shureiqi
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States.
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15
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Ackermann JA, Hofheinz K, Zaiss MM, Krönke G. The double-edged role of 12/15-lipoxygenase during inflammation and immunity. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:371-381. [PMID: 27480217 DOI: 10.1016/j.bbalip.2016.07.014] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 07/01/2016] [Accepted: 07/28/2016] [Indexed: 01/18/2023]
Abstract
12/15-Lipoxygenase (12/15-LOX) mediates the enzymatic oxidation of polyunsaturated fatty acids, thereby contributing to the generation of various bioactive lipid mediators. Although 12/15-LOX has been implicated in the pathogenesis of multiple chronic inflammatory diseases, its physiologic functions seem to include potent immune modulatory properties that physiologically contribute to the resolution of inflammation and the clearance of inflammation-associated tissue damage. This review aims to give a comprehensive overview about our current knowledge on the role of this enzyme during the regulation of inflammation and immunity. This article is part of a Special Issue entitled: Lipid modification and lipid peroxidation products in innate immunity and inflammation edited by Christoph J. Binder.
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Affiliation(s)
- Jochen A Ackermann
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University Hospital Erlangen, Erlangen, Germany; Nikolaus Fiebiger Center of Molecular Medicine, University Hospital Erlangen, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Katharina Hofheinz
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University Hospital Erlangen, Erlangen, Germany; Nikolaus Fiebiger Center of Molecular Medicine, University Hospital Erlangen, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Mario M Zaiss
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University Hospital Erlangen, Erlangen, Germany
| | - Gerhard Krönke
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University Hospital Erlangen, Erlangen, Germany; Nikolaus Fiebiger Center of Molecular Medicine, University Hospital Erlangen, University of Erlangen-Nuremberg, Erlangen, Germany.
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Abstract
The immune response comprises not only pro-inflammatory and anti-inflammatory pathways but also pro-resolution mechanisms that serve to balance the need of the host to target microbial pathogens while preventing excess inflammation and bystander tissue damage. Specialized pro-resolving mediators (SPMs) are enzymatically derived from essential fatty acids to serve as a novel class of immunoresolvents that limit acute responses and orchestrate the clearance of tissue pathogens, dying cells and debris from the battlefield of infectious inflammation. SPMs are composed of lipoxins, E-series and D-series resolvins, protectins and maresins. Individual members of the SPM family serve as agonists at cognate receptors to induce cell-type specific responses. Important regulatory roles for SPMs have been uncovered in host responses to several microorganisms, including bacterial, viral, fungal and parasitic pathogens. SPMs also promote the resolution of non-infectious inflammation and tissue injury. Defects in host SPM pathways contribute to the development of chronic inflammatory diseases. With the capacity to enhance host defence and modulate inflammation, SPMs represent a promising translational approach to enlist host resolution programmes for the treatment of infection and excess inflammation.
Here, the authors detail our current understanding of specialized pro-resolving mediators (SPMs), a family of endogenous mediators that have important roles in promoting the resolution of inflammation. With a focus on the lungs, they discuss the contribution of SPMs to infectious and chronic inflammatory diseases and their emerging therapeutic potential. Specialized pro-resolving mediators (SPMs) are enzymatically derived from essential fatty acids and have important roles in orchestrating the resolution of tissue inflammation — that is, catabasis. Host responses to tissue infection elicit acute inflammation in an attempt to control invading pathogens. SPMs are lipid mediators that are part of a larger family of pro-resolving molecules, which includes proteins and gases, that together restrain inflammation and resolve the infection. These immunoresolvents are distinct from immunosuppressive molecules as they not only dampen inflammation but also promote host defence. Here, we focus primarily on SPMs and their roles in lung infection and inflammation to illustrate the potent actions these mediators play in restoring tissue homeostasis after an infection.
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Romano M, Cianci E, Simiele F, Recchiuti A. Lipoxins and aspirin-triggered lipoxins in resolution of inflammation. Eur J Pharmacol 2015; 760:49-63. [DOI: 10.1016/j.ejphar.2015.03.083] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 03/27/2015] [Accepted: 03/30/2015] [Indexed: 02/08/2023]
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Abstract
Lipoxygenases (LOX) form a family of lipid peroxidizing enzymes, which have been implicated in a number of physiological processes and in the pathogenesis of inflammatory, hyperproliferative and neurodegenerative diseases. They occur in two of the three domains of terrestrial life (bacteria, eucarya) and the human genome involves six functional LOX genes, which encode for six different LOX isoforms. One of these isoforms is ALOX15, which has first been described in rabbits in 1974 as enzyme capable of oxidizing membrane phospholipids during the maturational breakdown of mitochondria in immature red blood cells. During the following decades ALOX15 has extensively been characterized and its biological functions have been studied in a number of cellular in vitro systems as well as in various whole animal disease models. This review is aimed at summarizing the current knowledge on the protein-chemical, molecular biological and enzymatic properties of ALOX15 in various species (human, mouse, rabbit, rat) as well as its implication in cellular physiology and in the pathogenesis of various diseases.
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Affiliation(s)
- Igor Ivanov
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Hartmut Kuhn
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany.
| | - Dagmar Heydeck
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
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Mao F, Wang M, Wang J, Xu WR. The role of 15-LOX-1 in colitis and colitis-associated colorectal cancer. Inflamm Res 2015; 64:661-9. [DOI: 10.1007/s00011-015-0852-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 07/04/2015] [Accepted: 07/06/2015] [Indexed: 02/08/2023] Open
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Mao F, Xu M, Zuo X, Yu J, Xu W, Moussalli MJ, Elias E, Li HS, Watowich SS, Shureiqi I. 15-Lipoxygenase-1 suppression of colitis-associated colon cancer through inhibition of the IL-6/STAT3 signaling pathway. FASEB J 2015; 29:2359-70. [PMID: 25713055 DOI: 10.1096/fj.14-264515] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 02/03/2015] [Indexed: 12/24/2022]
Abstract
The IL-6/signal transducer and activator of transcription 3 (STAT3) pathway is a critical signaling pathway for colitis-associated colorectal cancer (CAC). Peroxisome proliferator-activated receptor (PPAR)-δ, a lipid nuclear receptor, up-regulates IL-6. 15-Lipoxygenase-1 (15-LOX-1), which is crucial to production of lipid signaling mediators to terminate inflammation, down-regulates PPAR-δ. 15-LOX-1 effects on IL-6/STAT3 signaling and CAC tumorigenesis have not been determined. We report that intestinally targeted transgenic 15-LOX-1 expression in mice inhibited azoxymethane- and dextran sodium sulfate-induced CAC, IL-6 expression, STAT3 phosphorylation, and IL-6/STAT3 downstream target (Notch3 and MUC1) expression. 15-LOX-1 down-regulation was associated with IL-6 up-regulation in human colon cancer mucosa. Reexpression of 15-LOX-1 in human colon cancer cells suppressed IL-6 mRNA expression, STAT3 phosphorylation, IL-6 promoter activity, and PPAR-δ mRNA and protein expression. PPAR-δ overexpression in colonic epithelial cells promoted CAC tumorigenesis in mice and increased IL-6 expression and STAT3 phosphorylation, whereas concomitant 15-LOX-1 expression in colonic epithelial cells (15-LOX-1-PPAR-δ-Gut mice) suppressed these effects: the number of tumors per mouse (mean ± sem) was 4.22 ± 0.68 in wild-type littermates, 6.67 ± 0.83 in PPAR-δ-Gut mice (P = 0.026), and 2.25 ± 0.25 in 15-LOX-1-PPAR-δ-Gut mice (P = 0.0006). Identification of 15-LOX-1 suppression of PPAR-δ to inhibit IL-6/STAT3 signaling-driven CAC tumorigenesis provides mechanistic insights that can be used to molecularly target CAC.
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Affiliation(s)
- Fei Mao
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Min Xu
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Xiangsheng Zuo
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Jiang Yu
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Weiguo Xu
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Micheline J Moussalli
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Elias Elias
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Haiyan S Li
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Stephanie S Watowich
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Imad Shureiqi
- Departments of *Gastrointestinal Medical Oncology, Pathology, and Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA; and School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
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Brütsch SH, Wang CC, Li L, Stender H, Neziroglu N, Richter C, Kuhn H, Borchert A. Expression of inactive glutathione peroxidase 4 leads to embryonic lethality, and inactivation of the Alox15 gene does not rescue such knock-in mice. Antioxid Redox Signal 2015; 22:281-93. [PMID: 25313597 DOI: 10.1089/ars.2014.5967] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
AIMS Glutathione peroxidases (Gpx) and lipoxygenases (Alox) are functional counterplayers in the metabolism of hydroperoxy lipids that regulate cellular redox homeostasis. Gpx4 is a moonlighting protein that has been implicated not only as an enzyme in anti-oxidative defense, gene expression regulation, and programmed cell death, but also as a structural protein in spermatogenesis. Homozygous Gpx4 knock-out mice are not viable, but molecular reasons for intrauterine lethality are not completely understood. This study was aimed at investigating whether the lack of catalytic activity or the impaired function as structural protein is the dominant reason for embryonic lethality. We further explored whether the pro-oxidative enzyme mouse 12/15 lipoxygenase (Alox15) plays a major role in embryonic lethality of Gpx4-deficient mice. RESULTS To achieve these goals, we first created knock-in mice, which express a catalytically inactive Gpx4 mutant (Sec46Ala). As homozygous Gpx4-knock-out mice Sec46Ala-Gpx4(+/+) knock-in animals are not viable but undergo intrauterine resorption between embryonic day 6 and 7 (E6-7). In contrast, heterozygous knock-in mice (Sec46Ala-Gpx4(-/+)) are viable, fertile and do not show major phenotypic alterations. Interestingly, homozygous Alox15 deficiency did not rescue the U46A-Gpx4(+/+) mice from embryonic lethality. In fact, when heterozygous U46A-Gpx4(-/+) mice were stepwise crossed into an Alox15-deficent background, no viable U46A-Gpx4(+/+)+Alox15(-/-) individuals were obtained. However, we were able to identify U46A-Gpx4(+/+)+Alox15(-/-) embryos in the state of resorption around E7. INNOVATION AND CONCLUSION These data suggest that the lack of catalytic activity is the major reason for the embryonic lethality of Gpx4(-/-) mice and that systemic inactivation of the Alox15 gene does not rescue homozygous knock-in mice expressing catalytically silent Gpx4.
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Affiliation(s)
- Simone Hanna Brütsch
- 1 Institute of Biochemistry, Charite-University Medicine Berlin , Berlin, Germany
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22
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Horn T, Adel S, Schumann R, Sur S, Kakularam KR, Polamarasetty A, Redanna P, Kuhn H, Heydeck D. Evolutionary aspects of lipoxygenases and genetic diversity of human leukotriene signaling. Prog Lipid Res 2014; 57:13-39. [PMID: 25435097 PMCID: PMC7112624 DOI: 10.1016/j.plipres.2014.11.001] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 11/17/2014] [Accepted: 11/19/2014] [Indexed: 12/14/2022]
Abstract
Leukotrienes are pro-inflammatory lipid mediators, which are biosynthesized via the lipoxygenase pathway of the arachidonic acid cascade. Lipoxygenases form a family of lipid peroxidizing enzymes and human lipoxygenase isoforms have been implicated in the pathogenesis of inflammatory, hyperproliferative (cancer) and neurodegenerative diseases. Lipoxygenases are not restricted to humans but also occur in a large number of pro- and eucaryotic organisms. Lipoxygenase-like sequences have been identified in the three domains of life (bacteria, archaea, eucarya) but because of lacking functional data the occurrence of catalytically active lipoxygenases in archaea still remains an open question. Although the physiological and/or pathophysiological functions of various lipoxygenase isoforms have been studied throughout the last three decades there is no unifying concept for the biological importance of these enzymes. In this review we are summarizing the current knowledge on the distribution of lipoxygenases in living single and multicellular organisms with particular emphasis to higher vertebrates and will also focus on the genetic diversity of enzymes and receptors involved in human leukotriene signaling.
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Affiliation(s)
- Thomas Horn
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany; Department of Chemistry and Biochemistry, University of California - Santa Cruz, 1156 High Street, 95064 Santa Cruz, USA
| | - Susan Adel
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Ralf Schumann
- Institute of Microbiology, Charité - University Medicine Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Saubashya Sur
- Institute of Microbiology, Charité - University Medicine Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Kumar Reddy Kakularam
- Department of Animal Sciences, School of Life Science, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Aparoy Polamarasetty
- School of Life Sciences, University of Himachal Pradesh, Dharamshala, Himachal Pradesh 176215, India
| | - Pallu Redanna
- Department of Animal Sciences, School of Life Science, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India; National Institute of Animal Biotechnology, Miyapur, Hyderabad 500049, Telangana, India
| | - Hartmut Kuhn
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany.
| | - Dagmar Heydeck
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
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Soumya SJ, Binu S, Helen A, Reddanna P, Sudhakaran PR. 15-LOX metabolites and angiogenesis: angiostatic effect of 15(S)-HPETE involves induction of apoptosis in adipose endothelial cells. PeerJ 2014; 2:e635. [PMID: 25346880 PMCID: PMC4207198 DOI: 10.7717/peerj.635] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 10/01/2014] [Indexed: 11/20/2022] Open
Abstract
Inflammation is critical in the dysregulated growth of adipose tissue and associated vascular dysfunctions. 15-Lipoxygenase metabolites, important mediators of inflammation in adipose tissue during obese conditions, may contribute to codependence of inflammation and angiogenesis in adipose tissue. We have already reported the pro-angiogenic effect of 15(S)-HETE in adipose tissue. The present study was designed to understand the effect of 15(S)-HPETE, precursor of 15(S)-HETE, on angiogenesis in adipose tissue. Results showed that 15(S)-HPETE exerts an anti-angiogenic effect in adipose tissue. This was evidenced from decreased endothelial sprouting in adipose tissue explants, inhibition of angiogenic phenotype in adipose endothelial cells, decreased production of CD31 and VEGF in endothelial cells treated with 15(S)-HPETE. Further studies to examine the molecular mechanism of anti-angiogenic effect of 15(S)-HPETE showed that it inhibited cell survival signaling molecule Akt and anti-apoptotic Bcl-2 and also activated caspase-3 in adipose endothelial cells. These observations indicate that 15(S)-HPETE exerts its angiostatic effect in adipose tissue by inducing apoptosis of endothelial cells.
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Affiliation(s)
- Sasikumar J Soumya
- Department of Biochemistry, University of Kerala , Thiruvananthapuram, Kerala , India ; Inter-University Centre for Genomics and Gene Technology, University of Kerala , Kariavattom, Thiruvananthapuram, Kerala , India
| | - Sheela Binu
- Department of Biochemistry, University of Kerala , Thiruvananthapuram, Kerala , India
| | - Antony Helen
- Department of Biochemistry, University of Kerala , Thiruvananthapuram, Kerala , India
| | - Pallu Reddanna
- National Institute of Animal Biotechnology, University of Hyderabad , Hyderabad , India
| | - Perumana R Sudhakaran
- Department of Biochemistry, University of Kerala , Thiruvananthapuram, Kerala , India ; Department of Computational Biology and Bioinformatics, University of Kerala , Kariavattom, Thiruvananthapuram, Kerala , India
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Kuhn H, Banthiya S, van Leyen K. Mammalian lipoxygenases and their biological relevance. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:308-30. [PMID: 25316652 DOI: 10.1016/j.bbalip.2014.10.002] [Citation(s) in RCA: 402] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 09/30/2014] [Accepted: 10/03/2014] [Indexed: 02/07/2023]
Abstract
Lipoxygenases (LOXs) form a heterogeneous class of lipid peroxidizing enzymes, which have been implicated not only in cell proliferation and differentiation but also in the pathogenesis of various diseases with major public health relevance. As other fatty acid dioxygenases LOXs oxidize polyunsaturated fatty acids to their corresponding hydroperoxy derivatives, which are further transformed to bioactive lipid mediators (eicosanoids and related substances). On the other hand, lipoxygenases are key players in the regulation of the cellular redox homeostasis, which is an important element in gene expression regulation. Although the first mammalian lipoxygenases were discovered 40 years ago and although the enzymes have been well characterized with respect to their structural and functional properties the biological roles of the different lipoxygenase isoforms are not completely understood. This review is aimed at summarizing the current knowledge on the physiological roles of different mammalian LOX-isoforms and their patho-physiological function in inflammatory, metabolic, hyperproliferative, neurodegenerative and infectious disorders. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance".
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Affiliation(s)
- Hartmut Kuhn
- Institute of Biochemistry, University Medicine Berlin - Charite, Chariteplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany.
| | - Swathi Banthiya
- Institute of Biochemistry, University Medicine Berlin - Charite, Chariteplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Klaus van Leyen
- Neuroprotection Research Laboratory, Department of Radiology, Massachusetts Genrel Hospital and Harvard Medical School, Charlestown, MA, USA
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D'Souza Z, McAdoo SP, Smith J, Pusey CD, Cook HT, Behmoaras J, Aitman TJ. Experimental crescentic glomerulonephritis: a new bicongenic rat model. Dis Model Mech 2013; 6:1477-86. [PMID: 24046355 PMCID: PMC3820270 DOI: 10.1242/dmm.012328] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Crescentic glomerulonephritis (CRGN) is a major cause of human kidney failure, but the underlying mechanisms are not fully understood. Wistar Kyoto (WKY) rats are uniquely susceptible to CRGN following injection of nephrotoxic serum, whereas Lewis (LEW) rats are resistant. Our previous genetic studies of nephrotoxic nephritis (NTN), a form of CRGN induced by nephrotoxic serum, identified Fcgr3 and Jund as WKY genes underlying the two strongest quantitative trait loci for NTN phenotypes: Crgn1 and Crgn2, respectively. We also showed that introgression of WKY Crgn1 or Crgn2 individually into a LEW background did not lead to the formation of glomerular crescents. We have now generated a bicongenic strain, LEW.WCrgn1,2, in which WKY Crgn1 and Crgn2 are both introgressed into the LEW genetic background. These rats show development of NTN phenotypes, including glomerular crescents. Furthermore, we characterised macrophage function and glomerular cytokine profiles in this new strain. Additionally, we show that LEW.WCrgn1,2 rats are resistant to the development of glomerular crescents that is usually induced following immunisation with recombinant rat α3(IV)NC1, the specific Goodpasture autoantigen located in the glomerular basement membrane against which the immune response is directed in experimental autoimmune glomerulonephritis. Our results show that the new bicongenic strain responds differently to two distinct experimental triggers of CRGN. This is the first time that CRGN has been induced on a normally resistant rat genetic background and identifies the LEW.WCrgn1,2 strain as a new, potentially valuable model of macrophage-dependent glomerulonephritis.
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Affiliation(s)
- Zelpha D'Souza
- MRC Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK
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Uderhardt S, Krönke G. 12/15-lipoxygenase during the regulation of inflammation, immunity, and self-tolerance. J Mol Med (Berl) 2012; 90:1247-56. [PMID: 22983484 DOI: 10.1007/s00109-012-0954-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 08/22/2012] [Accepted: 08/27/2012] [Indexed: 12/20/2022]
Abstract
12/15-Lipoxygenase (12/15-LO) catalyzes the oxidation of free and esterified fatty acids thereby generating a whole spectrum of bioactive lipid mediators. This enzyme is involved in the regulation of various homeostatic processes as well as in the pathogenesis of multiple diseases. During the innate and adaptive immune response, 12/15-LO and its products exert both pro- and anti-inflammatory effects. Likewise, this enzyme has been implicated in the pathogenesis of autoimmune disease as well as in the maintenance of self-tolerance. This review will summarize our current knowledge about the role of 12/15-LO and will try to examine the two faces of this enzyme within the context of inflammation and immunity.
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Affiliation(s)
- Stefan Uderhardt
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University of Erlangen-Nuremberg, 91054 Erlangen, Germany
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27
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Zhu D, Ran Y. Role of 15-lipoxygenase/15-hydroxyeicosatetraenoic acid in hypoxia-induced pulmonary hypertension. J Physiol Sci 2012; 62:163-72. [PMID: 22331435 PMCID: PMC10717549 DOI: 10.1007/s12576-012-0196-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 01/25/2012] [Indexed: 12/01/2022]
Abstract
Pulmonary arterial hypertension (PAH) is a rare disease with a complex aetiology characterized by elevated pulmonary artery resistance, which leads to right heart ventricular afterload and ultimately progressing to right ventricular failure and often death. In addition to other factors, metabolites of arachidonic acid cascade play an important role in the pulmonary vasculature, and disruption of signaling pathways of arachidonic acid plays a central role in the pathogenesis of PAH. 15-Lipoxygenase (15-LO) is upregulated in pulmonary artery endothelial cells and smooth muscle cells of PAH patients, and its metabolite 15-hydroxyeicosatetraenoic acid (15-HETE) in particular seems to play a central role in the contractile machinery, and in the initiation and propagation of cell proliferation via its effects on signal pathways, mitogens, and cell cycle components. Here, we focus on our important research into the role played by 15-LO/15-HETE, which promotes a proliferative, antiapoptotic, and vasoconstrictive physiological milieu leading to hypoxic pulmonary hypertension.
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Affiliation(s)
- Daling Zhu
- College of Pharmacy, Harbin Medical University-Daqing, Daqing 163319, Heilongjiang, People's Republic of China.
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28
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He C, Wu Y, Lai Y, Cai Z, Liu Y, Lai L. Dynamic eicosanoid responses upon different inhibitor and combination treatments on the arachidonic acid metabolic network. MOLECULAR BIOSYSTEMS 2012; 8:1585-94. [DOI: 10.1039/c2mb05503a] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Abstract
15-Lipoxygenase-1 (15-LOX-1) is an inducible and highly regulated enzyme in normal human cells that plays a key role in the production of lipid signaling mediators, such as 13-hydroxyoctadecadienoic acid (13-HODE) from linoleic acid. 15-LOX-1 significantly contributes to the resolution of inflammation and to the terminal differentiation of normal cells. 15-LOX-1 is downregulated in human colorectal polyps and cancers. Emerging data support a tumor suppressor role for 15-LOX-1, especially in colon cancer. These data indicate that 15-LOX-1 promotes various anti-tumorigenic events, including cell differentiation and apoptosis, and inhibits chronic inflammation, angiogenesis, and metastasis. The transcriptional repression of 15-LOX-1 in colon cancer cells is complex and involves multiple mechanisms (e.g., histone methylation, transcriptional repressor binding). Re-expression of 15-LOX-1 in colon cancer cells can function as an important therapeutic mechanism and could be further exploited to develop novel treatment approaches for this common cancer.
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Affiliation(s)
- Sun IL Lee
- Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Xiangsheng Zuo
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Imad Shureiqi
- Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030
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30
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Affiliation(s)
- Motonao Nakamura
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, The University of Tokyo, Hongo, Tokyo, Japan.
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Abstract
Macrophages have long been regarded as classic mediators of innate immunity because of their production of proinflammatory cytokines and their ability to induce apoptotic cell death. As a result of such activities and the detrimental long-term effect of kidney inflammation, macrophages principally have been regarded as mediators of glomerular damage, tubular cell death, and the downstream fibrotic events leading to chronic kidney disease. Although this has been the accepted consequence of macrophage infiltration in kidney disease, macrophages also play a critical role in normal organ development, cell turnover, and recovery from injury in many organs, including the kidney. There is also a growing awareness that there is considerable heterogeneity of phenotype and function within the macrophage population and that a greater understanding of these different states of activation may result in the development of therapies specifically designed to capitalize on this variation in phenotype and cellular responses. In this review, we discuss the current understanding of induction and consequences of classic versus alternative macrophage activation and highlight what additional therapeutic options this may provide for the management of both acute and chronic kidney disease as well as renal cancer.
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Affiliation(s)
- Timothy M Williams
- Monash Immunology and Stem Cell Laboratories, Monash University, Clayton, Victoria, Australia
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Dobrian AD, Lieb DC, Cole BK, Taylor-Fishwick DA, Chakrabarti SK, Nadler JL. Functional and pathological roles of the 12- and 15-lipoxygenases. Prog Lipid Res 2010; 50:115-31. [PMID: 20970452 DOI: 10.1016/j.plipres.2010.10.005] [Citation(s) in RCA: 231] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 10/13/2010] [Accepted: 10/14/2010] [Indexed: 12/25/2022]
Abstract
The 12/15-lipoxygenase enzymes react with fatty acids producing active lipid metabolites that are involved in a number of significant disease states. The latter include type 1 and type 2 diabetes (and associated complications), cardiovascular disease, hypertension, renal disease, and the neurological conditions Alzheimer's disease and Parkinson's disease. A number of elegant studies over the last thirty years have contributed to unraveling the role that lipoxygenases play in chronic inflammation. The development of animal models with targeted gene deletions has led to a better understanding of the role that lipoxygenases play in various conditions. Selective inhibitors of the different lipoxygenase isoforms are an active area of investigation, and will be both an important research tool and a promising therapeutic target for treating a wide spectrum of human diseases.
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Affiliation(s)
- Anca D Dobrian
- Eastern Virginia Medical School, Department of Physiological Sciences, Lewis Hall, Room 2027, 700 W. Olney Road, Norfolk, VA 23507, United States.
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López-Novoa JM, Martínez-Salgado C, Rodríguez-Peña AB, Hernández FJL. Common pathophysiological mechanisms of chronic kidney disease: Therapeutic perspectives. Pharmacol Ther 2010; 128:61-81. [DOI: 10.1016/j.pharmthera.2010.05.006] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Accepted: 05/25/2010] [Indexed: 12/17/2022]
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Stables MJ, Gilroy DW. Old and new generation lipid mediators in acute inflammation and resolution. Prog Lipid Res 2010; 50:35-51. [PMID: 20655950 DOI: 10.1016/j.plipres.2010.07.005] [Citation(s) in RCA: 232] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 07/08/2010] [Accepted: 07/08/2010] [Indexed: 01/02/2023]
Abstract
Originally regarded as just membrane constituents and energy storing molecules, lipids are now recognised as potent signalling molecules that regulate a multitude of cellular responses via receptor-mediated pathways, including cell growth and death, and inflammation/infection. Derived from polyunsaturated fatty acids (PUFAs), such as arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), each lipid displays unique properties, thus making their role in inflammation distinct from that of other lipids derived from the same PUFA. The diversity of their actions arises because such metabolites are synthesised via discrete enzymatic pathways and because they elicit their response via different receptors. This review will collate the bioactive lipid research to date and summarise the findings in terms of the major pathways involved in their biosynthesis and their role in inflammation and its resolution. It will include lipids derived from AA (prostanoids, leukotrienes, 5-oxo-6,8,11,14-eicosatetraenoic acid, lipoxins and epoxyeicosatrienoic acids), EPA (E-series resolvins), and DHA (D-series resolvins, protectins and maresins).
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Affiliation(s)
- Melanie J Stables
- Centre for Clinical Pharmacology and Therapeutics, Division of Medicine, 5 University Street, University College London, London WC1E 6JJ, United Kingdom
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Shureiqi I, Chen D, Day RS, Zuo X, Hochman FL, Ross WA, Cole RA, Moy O, Morris JS, Xiao L, Newman RA, Yang P, Lippman SM. Profiling lipoxygenase metabolism in specific steps of colorectal tumorigenesis. Cancer Prev Res (Phila) 2010; 3:829-38. [PMID: 20570882 PMCID: PMC2900425 DOI: 10.1158/1940-6207.capr-09-0110] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Lipoxygenases (LOX) are key enzymes for the oxidative metabolism of polyunsaturated fatty acids into biologically active products. Clinical data on comparative levels of various LOX products in tumorigenesis are lacking. Therefore, we examined the profiles of several LOX products (5-LOX, 12-LOX, 15-LOX-1, and 15-LOX-2) by liquid chromatography/tandem mass spectrometry in the major steps of colorectal tumorigenesis (normal, polyp, and cancer) in a clinical study of 125 subjects (49 with normal colon, 36 with colorectal polyps, and 40 with colorectal cancer) who underwent prospective colorectal biopsies to control for various potential confounding factors (e.g., diet, medications). Mean 13-hydroxyoctadecadienoic acid (13-HODE) levels were significantly higher in normal colon [mean, 36.11 ng/mg protein; 95% confidence interval (95% CI), 31.56-40.67] than in paired colorectal cancer mucosa (mean, 27.01 ng/mg protein; 95% CI, 22.00-32.02; P = 0.0002), and in normal colon (mean, 37.15 ng/mg protein; 95% CI, 31.95-42.34) than in paired colorectal polyp mucosa (mean, 28.07 ng/mg protein; 95% CI, 23.66-32.48; P < 0.001). Mean 13-HODE levels, however, were similar between the left (mean, 37.15 ng/mg protein; 95% CI, 31.95-42.35) and the right normal colon (mean, 32.46 ng/mg protein; 95% CI, 27.95-36.98; P = 0.09). No significant differences with regard to 12- or 15-hydroxyeicosatetraenoic acid or leukotriene B(4) levels were detected between normal, polyp, and cancer mucosae. 15-LOX-1 inhibited interleukin-1beta expression. This study establishes that reduced 13-HODE levels are a specific alteration in the LOX product profile associated with human colorectal tumorigenesis.
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Affiliation(s)
- Imad Shureiqi
- Department of Clinical Cancer Prevention, The University of Texas M.D. Anderson Cancer Center, Houston, 77030-4009, USA.
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Peled N, Keith RL, Hirsch FR. Lung Cancer Prevention. Lung Cancer 2010. [DOI: 10.1007/978-1-60761-524-8_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Leedom AJ, Sullivan AB, Dong B, Lau D, Gronert K. Endogenous LXA4 circuits are determinants of pathological angiogenesis in response to chronic injury. THE AMERICAN JOURNAL OF PATHOLOGY 2009; 176:74-84. [PMID: 20008149 DOI: 10.2353/ajpath.2010.090678] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Inflammation and angiogenesis are intimately linked, and their dysregulation leads to pathological angiogenesis in human diseases. 15-lipoxygenase (15-LOX) and lipoxin A(4) receptors (ALX) constitute a LXA(4) circuit that is a key feature of inflammatory resolution. LXA(4) analogs have been shown to regulate vascular endothelial growth factor (VEGF)-A-induced angiogenic response in vitro. 15-LOX and ALX are highly expressed in the avascular and immune-privileged cornea. However, the role of this endogenous LXA(4) circuit in pathological neovascularization has not been determined. We report that suture-induced chronic injury in the cornea triggered polymorphonuclear leukocytes (PMN) infiltration, pathological neovascularization, and up-regulation of mediators of inflammatory angiogenesis, namely VEGF-A and the VEGF-3 receptor (FLT4). Up-regulation of the VEGF circuit and neovascularization correlated with selective changes in both 15-LOX (Alox15) and ALX (Fpr-rs2) expression and a temporally defined increase in basal 15-LOX activity. More importantly, genetic deletion of 15-LOX or 5-LOX, key and obligatory enzymes in the formation of LXA(4), respectively, led to exacerbated inflammatory neovascularization coincident with increased VEGF-A and FLT4 expression. Direct topical treatment with LXA(4), but not its metabolic precursor 15-hydroxyeicosatetraenoic acid, reduced expression of VEGF-A and FLT4 and inflammatory angiogenesis and rescued 15-LOX knockout mice from exacerbated angiogenesis. In summary, our findings and the prominent expression of 15-LOX and ALX in epithelial cells and macrophages place the LXA(4) circuit as an endogenous regulator of pathological angiogenesis.
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Affiliation(s)
- Alexander J Leedom
- Vision Science Program, School of Optometry, University of California, Berkeley, CA 94720-2020, USA
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Xu YW, Sun L, Liang H, Sun GM, Cheng Y. 12/15-Lipoxygenase inhibitor baicalein suppresses PPAR gamma expression and nuclear translocation induced by cerebral ischemia/reperfusion. Brain Res 2009; 1307:149-57. [PMID: 19853588 DOI: 10.1016/j.brainres.2009.10.038] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 10/14/2009] [Accepted: 10/15/2009] [Indexed: 11/27/2022]
Abstract
Accumulating evidences have demonstrated the beneficial actions of peroxisome proliferator-activated receptor gamma (PPAR gamma) in a variety of animal stroke models. Following middle cerebral artery occlusion (60 min) and 2-24 hr reperfusion in rats, we observed cerebral ischemia/reperfusion (I/R) induced up-regulation of PPAR gamma protein expression and translocation from the cytoplasm into the nucleus in a time-dependent manner. We also found that PPAR gamma agonist rosiglitazone enhanced whereas PPAR gamma antagonist GW9662 inhibited the alteration of PPAR gamma stimulated by I/R, suggesting that the changes of PPAR gamma may result from the activation by endogenous ligands. Moreover, the link between the 12/15-lipoxygenase and the production of activating ligands for PPAR gamma has been proved in various tissues. However, the relation of them in brain tissue has not been identified. We demonstrated that the I/R-induced PPAR gamma alteration was reversed by baicalein, the specific inhibitor of 12/15-lipoxygenase. Baicalein treatment significantly inhibited the up-regulation of PPAR gamma expression and, furthermore, suppressed PPAR gamma nuclear accumulation as well as maintained PPAR gamma cytoplasmic retention. Together, these results suggest that I/R induces both PPAR gamma expression and translocation, probably through the activation by endogenous ligands in a 12/15-lipoxygenase inhibitor-sensitive way.
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Affiliation(s)
- Yan-Wei Xu
- Tianjin Neurology Institute, Tianjin Medical University General Hospital, 154 Anshan Road Heping District, Tianjin 300052, China
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Abstract
The resolution of inflammation is an active process controlled by endogenous mediators with selective actions on neutrophils and monocytes. The initial phase of the acute inflammatory response is characterized by the production of pro-inflammatory mediators followed by a second phase in which lipid mediators with pro-resolution activities may be generated. The identification of these mediators has provided evidence for the dynamic regulation of the resolution of inflammation. Among these endogenous local mediators of resolution, lipoxins (LXs), lipid mediators typically formed during cell-cell interaction, were the first to be recognized. More recently, families of endogenous chemical mediators, termed resolvins and protectins, were discovered. LXs and aspirin-triggered LXs are considered to act as 'braking signals' in inflammation, limiting the trafficking of leukocytes to the inflammatory site. LXs are actively involved in the resolution of inflammation stimulating non-phlogistic phagocytosis of apoptotic cells by macrophages. Furthermore, LXs have emerged as potential anti-fibrotic mediators that may influence pro-fibrotic cytokines and matrix-associated gene expression in response to growth factors. Here, we provide a review and an update of the biosynthesis, metabolism and bioactions of LXs and LX analogues, and the recent studies on their therapeutic potential as promoters of resolution and fibro-suppressants.
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Affiliation(s)
- Paola Maderna
- UCD Diabetes Research Centre, UCD Conway Institute, School of Medicine and Medical Sciences, University College Dublin, Dublin, Ireland
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Abstract
The identification of nitric oxide ((*)NO) as an endogenously produced free radical mediator of endothelial-dependent relaxation and host defense has fundamentally changed concepts of cell signal transduction. Ligand-receptor oriented paradigms of cell signaling were originally centered on the concept of a high affinity and specific interaction between a ligand and its receptor, resulting in the activation of secondary signaling events such as gene expression or modulation of catalytic protein function. While (*)NO ligation of the heme iron of soluble guanylate cyclase is consistent with this perspective, the readily diffusible and broadly reactive (*)NO is increasingly appreciated to react with a vast array of target molecules that mediate paracrine vasodilator actions, inhibition of thrombosis and neointimal proliferation, and both pro- and antiinflammatory signaling reactions that are not affected by inhibitors of soluble guanylate cyclase. There is an expanding array of functionally significant "off target" collateral reactions mediated by (*)NO that are guanylate cyclase-independent and rather are dictated by anatomic distribution and the formation of secondary (*)NO-derived species. These reactions are a critical element of redox-regulated signaling and are addressed herein in the context of the oxidation of unsaturated fatty acids to vascular and inflammatory signaling mediators. Because of their abundance and the intrinsic reactivity of unsaturated lipid intermediates and eicosanoid metabolism enzymes with (*)NO and other oxides of nitrogen, lipid signaling mechanisms are a significant target for regulation by (*)NO in the vascular compartment. This convergence of (*)NO and lipid signaling pathways thus adds another level of regulation to physiological responses such as vasodilation, thrombosis, and inflammation. Herein, interactions between (*)NO and lipid signaling events are placed in the context of cardiovascular regulation.
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Affiliation(s)
- Volker Rudolph
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
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Liu C, Xu D, Liu L, Schain F, Brunnström Å, Björkholm M, Claesson HE, Sjöberg J. 15-Lipoxygenase-1 induces expression and release of chemokines in cultured human lung epithelial cells. Am J Physiol Lung Cell Mol Physiol 2009; 297:L196-203. [DOI: 10.1152/ajplung.00036.2008] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
15-Lipoxygenase-1 (15-LOX-1) has been proposed to be involved in various physiological and pathophysiological activities such as inflammation, atherosclerosis, cell maturation, and tumorigenesis. Asthma and chronic obstructive pulmonary disease are associated with increased expression of 15-LOX-1 in bronchial epithelial cells, but the potential functions of 15-LOX-1 in airway epithelial cells have not been well clarified. To study the function of 15-LOX-1 in bronchial epithelial cells, we ectopically expressed 15-LOX-1 in the human lung epithelial cell line A549. We found that overexpression of 15-LOX-1 in A549 cells leads to increased release of the chemokines MIP-1α, RANTES, and IP-10, and thereby to increased recruitment of immature dendritic cells, mast cells, and activated T cells. These results suggest that an increased expression and activity of 15-LOX-1 in lung epithelial cells is a proinflammatory event in the pathogenesis of asthma and other inflammatory lung disorders.
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Jin Y, Arita M, Zhang Q, Saban DR, Chauhan SK, Chiang N, Serhan CN, Dana R. Anti-angiogenesis effect of the novel anti-inflammatory and pro-resolving lipid mediators. Invest Ophthalmol Vis Sci 2009; 50:4743-52. [PMID: 19407006 DOI: 10.1167/iovs.08-2462] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
PURPOSE Resolvins and lipoxins are lipid mediators generated from essential polyunsaturated fatty acids that are the first dual anti-inflammatory and pro-resolving signals identified in the resolution phase of inflammation. Here the authors investigated the potential of aspirin-triggered lipoxin (LX) A4 analog (ATLa), resolving (Rv) D1, and RvE1, in regulating angiogenesis in a murine model. METHODS ATLa and RvE1 receptor expression was tested in different corneal cell populations by RT-PCR. Corneal neovascularization (CNV) was induced by suture or micropellet (IL-1 beta, VEGF-A) placement. Mice were then treated with ATLa, RvD1, RvE1, or vehicle, subconjunctivally at 48-hour intervals. Infiltration of neutrophils and macrophages was quantified after immunofluorescence staining. The mRNA expression levels of inflammatory cytokines, VEGFs, and VEGFRs were analyzed by real-time PCR. CNV was evaluated intravitally and morphometrically. RESULTS The receptors for LXA4, ALX/Fpr-rs-2 and for RvE1, ChemR23 were each expressed by epithelium, stromal keratocytes, and infiltrated CD11b(+) cells in corneas. Compared to the vehicle-treated eye, ATLa-, RvD1-, and RvE1-treated eyes had reduced numbers of infiltrating neutrophils and macrophages and reduced mRNA expression levels of TNF-alpha, IL-1 alpha, IL-1 beta, VEGF-A, VEGF-C, and VEGFR2. Animals treated with these mediators had significantly suppressed suture-induced or IL-1 beta-induced hemangiogenesis (HA) but not lymphangiogenesis. Interestingly, only the application of ATLa significantly suppressed VEGF-A-induced HA. CONCLUSIONS ATLa, RvE1, and RvD1 all reduce inflammatory corneal HA by early regulation of resolution mechanisms in innate immune responses. In addition, ATLa directly inhibits VEGF-A-mediated angiogenesis and is the most potent inhibitor of NV among this new genus of dual anti-inflammatory and pro-resolving lipid mediators.
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Affiliation(s)
- Yiping Jin
- Department of Ophthalmology, Schepens Eye Research Institute, Harvard Medical School, 20 Staniford Street, Boston, MA 02114, USA
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Hassan IR, Gronert K. Acute changes in dietary omega-3 and omega-6 polyunsaturated fatty acids have a pronounced impact on survival following ischemic renal injury and formation of renoprotective docosahexaenoic acid-derived protectin D1. THE JOURNAL OF IMMUNOLOGY 2009; 182:3223-32. [PMID: 19234220 DOI: 10.4049/jimmunol.0802064] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Exacerbated inflammation plays an important role in the pathogenesis of ischemic renal injury (IRI), which is the major cause of intrinsic acute renal failure. Clinical studies suggest that long-term treatment with omega-3 polyunsaturated fatty acids (PUFA) improves renal function and lowers the risk of death or end-stage renal disease. Docosahexaenoic acid, a principle omega-3 PUFA of fish oils, is of particular interest as it is found in most human tissues and is converted to protectin D1 (PD1), which exhibits antiinflammatory and proresolving bioactions. We set out to investigate the impact of acute dietary modulation of omega-3 or omega-6 PUFA on IRI and renal lipid autacoid circuits, using an established mouse model and liquid chromatography-mass spectroscopy/mass spectroscopy-based lipidomics. Thirty minutes of renal ischemia significantly elevated serum creatinine in the omega-6 diet group while renal function remained normal in the matched omega-3 diet group. Notably, extending ischemia to 45 min caused 100% mortality in the omega-6 group, in sharp contrast to 0% mortality in the omega-3 group. Protection against IRI in the omega-3 group correlated with decreased polymorphonuclear leukocyte recruitment, chemokine and cytokine levels, abrogated formation of lipoxygenase- and cyclooxygenase-derived eicosanoids, and increased renal levels of PD1. Systemic treatment with PD1 reduced kidney polymorphonuclear leukocyte influx and, more importantly, amplified renoprotective heme-oxygenase-1 protein and mRNA expression in injured and uninjured kidneys. These findings suggest therapeutic or dietary amplification of PD1 circuits restrains acute renal injury and that short-term changes in dietary omega-3 and omega-6 PUFA dramatically impacts renal lipid autacoid formation and outcome of IRI.
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Affiliation(s)
- Iram R Hassan
- New York Medical College, Department of Pharmacology, Valhalla, NY 10595, USA
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Chabane N, Zayed N, Benderdour M, Martel-Pelletier J, Pelletier JP, Duval N, Fahmi H. Human articular chondrocytes express 15-lipoxygenase-1 and -2: potential role in osteoarthritis. Arthritis Res Ther 2009; 11:R44. [PMID: 19296842 PMCID: PMC2688191 DOI: 10.1186/ar2652] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 03/04/2009] [Accepted: 03/18/2009] [Indexed: 01/24/2023] Open
Abstract
Introduction 15-Lipoxygenases and their metabolites have been shown to exhibit anti-inflammatory and immunomodulatory properties, but little is known regarding their expression and function in chondrocytes. The objective of this study was to evaluate the expression of 15-lipoxygenase-1 and -2 in human articular chondrocytes, and to investigate the effects of their metabolites 13(S)-hydroxy octadecadienoic and 15(S)-hydroxyeicosatetraenoic acids on IL-1β-induced matrix metalloproteinase (MMP)-1 and MMP-13 expression. Methods The expression levels of 15-lipoxygenase-1 and -2 were analyzed by reverse transcription PCR and Western blotting in chondrocytes, and by immunohistochemistry in cartilage. Chondrocytes or cartilage explants were stimulated with IL-1β in the absence or presence of 13(S)-hydroxy octadecadienoic and 15(S)-hydroxyeicosatetraenoic acids, and the levels of MMP-1 and MMP-13 protein production and type II collagen cleavage were evaluated using immunoassays. The role of peroxisome proliferator-activated receptor (PPAR)γ was evaluated using transient transfection experiments and the PPARγ antagonist GW9662. Results Articular chondrocytes express 15-lipoxygenase-1 and -2 at the mRNA and protein levels. 13(S)-hydroxy octadecadienoic and 15(S)-hydroxyeicosatetraenoic acids dose dependently decreased IL-1β-induced MMP-1 and MMP-13 protein and mRNA expression as well as type II collagen cleavage. The effect on MMP-1 and MMP-13 expression does not require de novo protein synthesis. 13(S)-hydroxy octadecadienoic and 15(S)-hydroxyeicosatetraenoic acids activated endogenous PPARγ, and GW9662 prevented their suppressive effect on MMP-1 and MMP-13 production, suggesting the involvement of PPARγ in these effects. Conclusions This study is the first to demonstrate the expression of 15-lipoxygenase-1 and -2 in articular chondrocytes. Their respective metabolites, namely 13(S)-hydroxy octadecadienoic and 15(S)-hydroxyeicosatetraenoic acids, suppressed IL-1β-induced MMP-1 and MMP-13 expression in a PPARγ-dependent pathway. These data suggest that 15-lipoxygenases may have chondroprotective properties by reducing MMP-1 and MMP-13 expression.
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Affiliation(s)
- Nadir Chabane
- Osteoarthritis Research Unit, Research Centre of the University of Montreal Hospital Center, Notre-Dame Hospital, Montreal, Quebec, Canada.
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Wu SH, Liao PY, Yin PL, Zhang YM, Dong L. Elevated expressions of 15-lipoxygenase and lipoxin A4 in children with acute poststreptococcal glomerulonephritis. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 174:115-22. [PMID: 19095947 DOI: 10.2353/ajpath.2009.080671] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Anti-inflammatory effects of the 15-lipoxygenase (15-LO) derivatives lipoxin A(4) (LXA(4)) and 15-S-hydroxyeicosatetraenoic acid (15-S-HETE) have been documented in many experimental models of acute inflammation. However, the expression levels of 15-LO and its products in human renal diseases remain unknown. This study investigated the expression levels of LXA(4), leukotriene B(4) (LTB(4)), and 15-LO in leukocytes and glomeruli obtained from 22 children with acute poststreptococcal glomerulonephritis (APSGN), and determined the modulatory effects of both 15-S-HETE and LXA(4) on LTB(4) synthesis in leukocytes and LTB(4)-evoked chemotaxis of polymorphonuclear leukocytes (PMNs) obtained from children during the first 3 days after onset of APSGN. Expression levels of both LXA(4) and 15-LO in leukocytes and glomeruli were up-regulated during the acute phase of disease, further peaking between days 10 and 14, and remained increased after 6 to 8 weeks of APSGN onset. In contrast, blood and urinary levels of LTB(4) as well as the number of glomerular PMNs peaked during the acute phase of disease and then decreased during the resolution phase. Administration of both 15-S-HETE and LXA(4) in vitro inhibited LTB(4)-induced chemotaxis of PMNs and production of LTB(4) from leukocytes obtained from patients with APSGN. The current study provides further support for an anti-inflammatory role for 15-LO products in human nephritis through both antagonism and inhibition of leukotriene synthesis and its biological activity.
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Affiliation(s)
- Sheng-Hua Wu
- Department of Pediatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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Zuo X, Morris JS, Shureiqi I. Chromatin modification requirements for 15-lipoxygenase-1 transcriptional reactivation in colon cancer cells. J Biol Chem 2008; 283:31341-7. [PMID: 18799463 PMCID: PMC2581547 DOI: 10.1074/jbc.m803729200] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Revised: 09/15/2008] [Indexed: 01/26/2023] Open
Abstract
15-Lipoxygenase-1 (15-LOX-1) contributes significantly to inflammation regulation and terminal cell differentiation. 15-LOX-1 is transcriptionally silenced in cancer cells, and its transcriptional reactivation (e.g. via histone deacetylase inhibitors (HDACIs)) is essential for restoring terminal cell differentiation to cancer cells. STAT-6 acetylation via the histone acetyltransferase KAT3B has been proposed to be necessary for 15-LOX-1 transcriptional activation. However, the exact mechanism underlying 15-LOX-1 transcriptional reactivation in cancer cells is still undefined, especially in regard to the contribution of 15-LOX-1 promoter histone modifications. We therefore examined the relative mechanistic contributions of 15-LOX-1 promoter histone modifications and STAT-6 to 15-LOX-1 transcriptional reactivation by HDACIs in colon cancer cells. We found that: 1) histone H3 and H4 acetylation in the 15-LOX-1 promoter through KAT3B was critical to 15-LOX-1 transcriptional activation; 2) 15-LOX-1 transcription was activated independently from STAT-6; and 3) dimethyl-histone H3 lysine 9 (H3K9me2) demethylation in the 15-LOX-1 promoter via the histone lysine demethylase KDM3A was an early and specific histone modification and was necessary for activation of transcription. These findings demonstrate that histone modification in the 15-LOX-1 promoter is important to 15-LOX-1 transcriptional silencing in colon cancer cells and that HDACIs can activate gene transcription via KDM3A demethylation of H3K9me2.
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Affiliation(s)
- Xiangsheng Zuo
- Department of Clinical Cancer Prevention, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA
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O'Meara SJ, Rodgers K, Godson C. Lipoxins: update and impact of endogenous pro-resolution lipid mediators. Rev Physiol Biochem Pharmacol 2008; 160:47-70. [PMID: 18481030 DOI: 10.1007/112_2006_0606] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Lipoxins (LXs) are endogenously produced eicosanoids that are typically generated by transcellular biosynthesis. These trihydroxytetraene-containing lipid mediators and their stable synthetic analogues possess a wide spectrum of anti-inflammatory and pro-resolution bioactions both in vitro and in vivo. More recently, LXs have emerged as potential anti-fibrotic mediators that may influence pro-fibrotic cytokines and matrix-associated gene expression in response to platelet-derived growth factor (PDGF). Here we review the biosynthesis, metabolism and bioactions of LXs and LX analogues and their therapeutic potential.
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Affiliation(s)
- S J O'Meara
- UCD Conway Institute of Biomolecular and Biomedical Research and UCB Diabetes Research Center, School of Medicine and Medical Sciences, University College Dublin, Belfield, Dublin 4, Ireland
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Planagumà A, Kazani S, Marigowda G, Haworth O, Mariani TJ, Israel E, Bleecker ER, Curran-Everett D, Erzurum SC, Calhoun WJ, Castro M, Chung KF, Gaston B, Jarjour NN, Busse WW, Wenzel SE, Levy BD. Airway lipoxin A4 generation and lipoxin A4 receptor expression are decreased in severe asthma. Am J Respir Crit Care Med 2008; 178:574-82. [PMID: 18583575 DOI: 10.1164/rccm.200801-061oc] [Citation(s) in RCA: 187] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
RATIONALE Airway inflammation is common in severe asthma despite antiinflammatory therapy with corticosteroids. Lipoxin A(4) (LXA(4)) is an arachidonic acid-derived mediator that serves as an agonist for resolution of inflammation. OBJECTIVES Airway levels of LXA(4), as well as the expression of lipoxin biosynthetic genes and receptors, in severe asthma. METHODS Samples of bronchoalveolar lavage fluid were obtained from subjects with asthma and levels of LXA(4) and related eicosanoids were measured. Expression of lipoxin biosynthetic genes was determined in whole blood, bronchoalveolar lavage cells, and endobronchial biopsies by quantitative polymerase chain reaction, and leukocyte LXA(4) receptors were monitored by flow cytometry. MEASUREMENTS AND MAIN RESULTS Individuals with severe asthma had significantly less LXA(4) in bronchoalveolar lavage fluids (11.2 +/- 2.1 pg/ml) than did subjects with nonsevere asthma (150.1 +/- 38.5 pg/ml; P < 0.05). In contrast, levels of cysteinyl leukotrienes were increased in both asthma cohorts compared with healthy individuals. In severe asthma, 15-lipoxygenase-1 mean expression was decreased fivefold in bronchoalveolar lavage cells. In contrast, 15-lipoxgenase-1 was increased threefold in endobronchial biopsies, but expression of both 5-lipoxygenase and 15-lipoxygenase-2 in these samples was decreased. Cyclooxygenase-2 expression was decreased in all anatomic compartments sampled in severe asthma. Moreover, LXA(4) receptor gene and protein expression were significantly decreased in severe asthma peripheral blood granulocytes. CONCLUSIONS Mechanisms underlying pathological airway responses in severe asthma include lipoxin underproduction with decreased expression of lipoxin biosynthetic enzymes and receptors. Together, these results indicate that severe asthma is characterized, in part, by defective lipoxin counterregulatory signaling circuits.
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Affiliation(s)
- Anna Planagumà
- Pulmonary and Critical Care Medicine Division, Department of Internal Medicine, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA
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Yuan H, Lanting L, Xu ZG, Li SL, Swiderski P, Putta S, Jonnalagadda M, Kato M, Natarajan R. Effects of cholesterol-tagged small interfering RNAs targeting 12/15-lipoxygenase on parameters of diabetic nephropathy in a mouse model of type 1 diabetes. Am J Physiol Renal Physiol 2008; 295:F605-17. [PMID: 18562637 DOI: 10.1152/ajprenal.90268.2008] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
We previously showed that the 12/15-lipoxygenase (12/15-LO) pathway of arachidonate acid metabolism is involved in multiple events related to diabetic nephropathy (DN), including glomerular hypertrophy and extracellular matrix deposition (Kang SW, Adler SG, Nast CC, LaPage J, Gu JL, Nadler JL, Natarajan R. Kidney Int 59: 1354-1362, 2001; Kang SW, Natarajan R, Shahed A, Nast CC, LaPage J, Mundel P, Kashtan C, Adler SG. J Am Soc Nephrol 14: 3178-3187, 2003; Kim YS, Lanting L, Adler SG, Natarajan R. Kindney Int 64: 1702-1714, 2003; Reddy MA, Adler SG, Kim YS, Lanting L, Rossi JJ, Kang SW, Nadler JL, Shahed A, Natarajan R. Am J Physiol Renal Physiol 283: F985-F994, 2002). In this study, we investigated whether in vivo delivery of small interfering RNAs (siRNAs) targeting 12/15-LO can ameliorate renal injury and DN in a streptozotocin-injected mouse model of type 1 diabetes. To achieve greater in vivo access and siRNA expression in the kidney, we used double-stranded 12/15-LO siRNA oligonucleotides conjugated with cholesterol. Diabetic DBA/2J mice were injected subcutaneously with either cholesterol-tagged 12/15-LO siRNA, mismatched control siRNA, or vehicle alone, twice weekly for 7 wk. Relative to controls, mice that received 12/15-LO siRNA showed significant reduction in albuminuria, kidney-to-body weight ratios, glomerular mesangial matrix expansion, renal structural damage, and monocyte/macrophage infiltration. These effects were associated with lower renal cortical or glomerular levels of profibrotic markers transforming growth factor-beta, connective tissue growth factor, type I and type IV collagens, plasminogen activator inhibitor 1, and fibronectin. The diabetes-induced increase in glomerular cyclin-dependent kinase inhibitors that are associated with hypertrophy was also prevented by siRNA administration. Our results show for the first time that systemic delivery of cholesterol-tagged siRNAs targeting 12/15-LO has renoprotective effects under diabetic conditions and therefore could be a novel therapeutic approach for DN.
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Affiliation(s)
- Hang Yuan
- Department of Diabetes, Beckman Research Institute, City of Hope, Duarte, California, USA
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Merched AJ, Ko K, Gotlinger KH, Serhan CN, Chan L. Atherosclerosis: evidence for impairment of resolution of vascular inflammation governed by specific lipid mediators. FASEB J 2008; 22:3595-606. [PMID: 18559988 DOI: 10.1096/fj.08-112201] [Citation(s) in RCA: 325] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Atherosclerosis is now recognized as an inflammatory disease involving the vascular wall. Recent results indicate that acute inflammation does not simply passively resolve as previously assumed but is actively terminated by a homeostatic process that is governed by specific lipid-derived mediators initiated by lipoxygenases. Experiments with animals and humans support a proinflammatory role for the 5-lipoxygenase system. In contrast, results from animal experiments show a range of responses with the 12/15-lipoxygenase pathways in atherosclerosis. To date, the only two clinical epidemiology human studies both support an antiatherogenic role for 12/15-lipoxygenase downstream actions. We tested the hypothesis that atherosclerosis results from a failure in the resolution of local inflammation by analyzing apolipoprotein E-deficient mice with 1) global leukocyte 12/15-lipoxygenase deficiency, 2) normal enzyme expression, or 3) macrophage-specific 12/15-lipoxygenase overexpression. Results from these indicate that 12/15-lipoxygenase expression protects mice against atherosclerosis via its role in the local biosynthesis of lipid mediators, including lipoxin A(4), resolvin D1, and protectin D1. These mediators exert potent agonist actions on macrophages and vascular endothelial cells that can control the magnitude of the local inflammatory response. Taken together, these findings suggest that a failure of local endogenous resolution mechanisms may underlie the unremitting inflammation that fuels atherosclerosis.
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Affiliation(s)
- Aksam J Merched
- Department of Molecular and Cellular Biology, Baylor College of Medicine and St. Luke's Episcopal Hospital, Houston, TX 77030, USA.
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