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Burke ND, Nixon B, Roman SD, Schjenken JE, Walters JLH, Aitken RJ, Bromfield EG. Male infertility and somatic health - insights into lipid damage as a mechanistic link. Nat Rev Urol 2022; 19:727-750. [PMID: 36100661 DOI: 10.1038/s41585-022-00640-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2022] [Indexed: 11/08/2022]
Abstract
Over the past decade, mounting evidence has shown an alarming association between male subfertility and poor somatic health, with substantial evidence supporting the increased incidence of oncological disease, cardiovascular disease, metabolic disorders and autoimmune diseases in men who have previously received a subfertility diagnosis. This paradigm is concerning, but might also provide a novel window for a crucial health reform in which the infertile phenotype could serve as an indication of potential pathological conditions. One of the major limiting factors in this association is the poor understanding of the molecular features that link infertility with comorbidities across the life course. Enzymes involved in the lipid oxidation process might provide novel clues to reconcile the mechanistic basis of infertility with incident pathological conditions. Building research capacity in this area is essential to enhance the early detection of disease states and provide crucial information about the disease risk of offspring conceived through assisted reproduction.
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Affiliation(s)
- Nathan D Burke
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, Infertility and Reproduction Research Program, New Lambton Heights, New South Wales, Australia
| | - Brett Nixon
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, Infertility and Reproduction Research Program, New Lambton Heights, New South Wales, Australia
| | - Shaun D Roman
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, Infertility and Reproduction Research Program, New Lambton Heights, New South Wales, Australia
- Priority Research Centre for Drug Development, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - John E Schjenken
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, Infertility and Reproduction Research Program, New Lambton Heights, New South Wales, Australia
| | - Jessica L H Walters
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, Infertility and Reproduction Research Program, New Lambton Heights, New South Wales, Australia
| | - R John Aitken
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, Infertility and Reproduction Research Program, New Lambton Heights, New South Wales, Australia
| | - Elizabeth G Bromfield
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia.
- Hunter Medical Research Institute, Infertility and Reproduction Research Program, New Lambton Heights, New South Wales, Australia.
- Department of Biomolecular Health Sciences, Utrecht University, Utrecht, Netherlands.
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2
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The Role of Transcription Factor PPAR-γ in the Pathogenesis of Psoriasis, Skin Cells, and Immune Cells. Int J Mol Sci 2022; 23:ijms23179708. [PMID: 36077103 PMCID: PMC9456565 DOI: 10.3390/ijms23179708] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 11/22/2022] Open
Abstract
The peroxisome proliferator-activated receptor PPAR-γ is one of three PPAR nuclear receptors that act as ligand-activated transcription factors. In immune cells, the skin, and other organs, PPAR-γ regulates lipid, glucose, and amino acid metabolism. The receptor translates nutritional, pharmacological, and metabolic stimuli into the changes in gene expression. The activation of PPAR-γ promotes cell differentiation, reduces the proliferation rate, and modulates the immune response. In the skin, PPARs also contribute to the functioning of the skin barrier. Since we know that the route from identification to the registration of drugs is long and expensive, PPAR-γ agonists already approved for other diseases may also represent a high interest for psoriasis. In this review, we discuss the role of PPAR-γ in the activation, differentiation, and proliferation of skin and immune cells affected by psoriasis and in contributing to the pathogenesis of the disease. We also evaluate whether the agonists of PPAR-γ may become one of the therapeutic options to suppress the inflammatory response in lesional psoriatic skin and decrease the influence of comorbidities associated with psoriasis.
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Zhao T, Wang Y, Guo X, Li H, Jiang W, Xiao Y, Deng B, Sun Y. Altered oxylipin levels in human vitreous indicate imbalance in pro-/anti-inflammatory homeostasis in proliferative diabetic retinopathy. Exp Eye Res 2021; 214:108799. [PMID: 34687725 DOI: 10.1016/j.exer.2021.108799] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 09/23/2021] [Accepted: 10/18/2021] [Indexed: 12/16/2022]
Abstract
Proliferative diabetic retinopathy (PDR) is an advanced stage of diabetic retinopathy (DR), characterized by retinal neovascularization. It is a progressive fundus disease and a severe complication of diabetes that causes vision impairment. Hyperglycemia-induced persistent low-grade inflammation is a crucial factor underlying the pathogenesis of DR-associated damage and contributing to the progression of PDR. Highly enriched polyunsaturated fatty acids (PUFAs) in the retina are precursors to oxidized metabolites, namely, oxylipins, which exert pro-inflammatory or anti-inflammatory (resolving) effects under different pathological conditions and have been implicated in diabetes. To evaluate differences in oxylipin levels in the vitreous obtained from PDR and non-diabetic subjects, we performed a targeted assessment of oxylipins. A total of 41 patients with PDR and 22 non-diabetic control subjects were enrolled in this study. Vitreous humor obtained during routinely scheduled vitrectomy underwent a targeted but unbiased screening for oxylipins using mass spectrometry-based lipidomics. We found 21 oxylipins showing statistically significant differences in their levels between PDR and non-diabetic subjects (p < 0.05). Lipoxygenase (LOX)- and cytochrome P450 (CYP)- derived oxylipins were the most affected, while cyclooxygenase (COX) oxylipins were affected to a lesser extent. When categorized by their precursor PUFAs, ±19,20-EpDPE, a CYP product of docosahexaenoic acid (DHA) and 12S-HETE, a LOX product of arachidonic acid (ARA), were increased by the largest magnitude. Moreover, of these 21 oxylipins, 7 were considered as potential biomarkers for discriminating PDR patients from the non-diabetic controls. Our results indicate that altered oxylipin levels in the vitreous implicate an underlying imbalanced inflammation-resolution homeostasis in PDR.
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Affiliation(s)
- Tantai Zhao
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Hunan Clinical Research Center of Ophthalmic Disease, Changsha, Hunan, China
| | - Yanbin Wang
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Hunan Clinical Research Center of Ophthalmic Disease, Changsha, Hunan, China
| | - Xiaojian Guo
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Hunan Clinical Research Center of Ophthalmic Disease, Changsha, Hunan, China
| | - Huiling Li
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Hunan Clinical Research Center of Ophthalmic Disease, Changsha, Hunan, China
| | - Wenmin Jiang
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Hunan Clinical Research Center of Ophthalmic Disease, Changsha, Hunan, China
| | - Yangyan Xiao
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Hunan Clinical Research Center of Ophthalmic Disease, Changsha, Hunan, China
| | - Bin Deng
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Hunan Clinical Research Center of Ophthalmic Disease, Changsha, Hunan, China
| | - Yun Sun
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Hunan Clinical Research Center of Ophthalmic Disease, Changsha, Hunan, China.
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4
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Du Y, Taylor CG, Aukema HM, Zahradka P. Role of oxylipins generated from dietary PUFAs in the modulation of endothelial cell function. Prostaglandins Leukot Essent Fatty Acids 2020; 160:102160. [PMID: 32717531 DOI: 10.1016/j.plefa.2020.102160] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/17/2020] [Accepted: 07/17/2020] [Indexed: 12/13/2022]
Abstract
Oxylipins, which are circulating bioactive lipids generated from polyunsaturated fatty acids (PUFAs) by cyclooxygenase, lipooxygenase and cytochrome P450 enzymes, have diverse effects on endothelial cells. Although studies of the effects of oxylipins on endothelial cell function are accumulating, a review that provides a comprehensive compilation of current knowledge and recent advances in the context of vascular homeostasis is lacking. This is the first compilation of the various in vitro, ex vivo and in vivo reports to examine the effects and potential mechanisms of action of oxylipins on endothelial cells. The aggregate data indicate docosahexaenoic acid-derived oxylipins consistently show beneficial effects related to key endothelial cell functions, whereas oxylipins derived from other PUFAs exhibit both positive and negative effects. Furthermore, information is lacking for certain oxylipin classes, such as those derived from α-linolenic acid, which suggests additional studies are required to achieve a full understanding of how oxylipins affect endothelial cells.
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Affiliation(s)
- Youjia Du
- Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada; Department of Physiology and Pathophysiology, University of Manitoba, MB R3E 0J9, Canada
| | - Carla G Taylor
- Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada; Department of Physiology and Pathophysiology, University of Manitoba, MB R3E 0J9, Canada; Department of Food and Human Nutritional Sciences, University of Manitoba, MB R3T 2N2, Canada
| | - Harold M Aukema
- Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada; Department of Food and Human Nutritional Sciences, University of Manitoba, MB R3T 2N2, Canada
| | - Peter Zahradka
- Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada; Department of Physiology and Pathophysiology, University of Manitoba, MB R3E 0J9, Canada; Department of Food and Human Nutritional Sciences, University of Manitoba, MB R3T 2N2, Canada.
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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: 173] [Impact Index Per Article: 34.6] [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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Yeung J, Holinstat M. Who is the real 12-HETrE? Prostaglandins Other Lipid Mediat 2017; 132:25-30. [PMID: 28259546 DOI: 10.1016/j.prostaglandins.2017.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 02/16/2017] [Accepted: 02/28/2017] [Indexed: 12/24/2022]
Abstract
Oxygenases, including lipoxygenases and cytochrome P450s, generate an array of structurally diverse oxylipins that modulate distinct biological responses in mammals. Depending on the source of tissues and enzymes, distinct oxylipins are generated with inherent cellular function. Here, we report structurally different forms of 12-HETrE, with distinct biological function in tissues as well as their derived enzymatic source.
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Affiliation(s)
- Jennifer Yeung
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, United States
| | - Michael Holinstat
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, United States; Department of Internal Medicine, Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, MI, United States.
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Tuncer S, Banerjee S. Eicosanoid pathway in colorectal cancer: Recent updates. World J Gastroenterol 2015; 21:11748-11766. [PMID: 26557000 PMCID: PMC4631974 DOI: 10.3748/wjg.v21.i41.11748] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 06/25/2015] [Accepted: 08/31/2015] [Indexed: 02/06/2023] Open
Abstract
Enzymatic metabolism of the 20C polyunsaturated fatty acid (PUFA) arachidonic acid (AA) occurs via the cyclooxygenase (COX) and lipoxygenase (LOX) pathways, and leads to the production of various bioactive lipids termed eicosanoids. These eicosanoids have a variety of functions, including stimulation of homeostatic responses in the cardiovascular system, induction and resolution of inflammation, and modulation of immune responses against diseases associated with chronic inflammation, such as cancer. Because chronic inflammation is essential for the development of colorectal cancer (CRC), it is not surprising that many eicosanoids are implicated in CRC. Oftentimes, these autacoids work in an antagonistic and highly temporal manner in inflammation; therefore, inhibition of the pro-inflammatory COX-2 or 5-LOX enzymes may subsequently inhibit the formation of their essential products, or shunt substrates from one pathway to another, leading to undesirable side-effects. A better understanding of these different enzymes and their products is essential not only for understanding the importance of eicosanoids, but also for designing more effective drugs that solely target the inflammatory molecules found in both chronic inflammation and cancer. In this review, we have evaluated the cancer promoting and anti-cancer roles of different eicosanoids in CRC, and highlighted the most recent literature which describes how those molecules affect not only tumor tissue, but also the tumor microenvironment. Additionally, we have attempted to delineate the roles that eicosanoids with opposing functions play in neoplastic transformation in CRC through their effects on proliferation, apoptosis, motility, metastasis, and angiogenesis.
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Wang R, He A, Ramu E, Falck JR. Studies towards asymmetric synthesis of 4(S)-11-dihydroxydocosahexaenoic acid (diHDHA) featuring cross-coupling of chiral stannane under mild conditions. Org Biomol Chem 2015; 13:1624-8. [PMID: 25425336 DOI: 10.1039/c4ob02324b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient and asymmetric synthetic approach towards one of the biologically interesting 4(S)-11-diHDHA derivatives was developed. This process mainly relied on two reactions, one is the copper-catalyzed mild cross-coupling that allows for the efficient construction of a chiral α-alkynyl α-hydroxy motif and another is the synthesis of chiral α-hydroxy α-stannanes that has previously been developed by our group featuring the asymmetric stannylation using the well-established tributyltin hydride/diethyl zinc system from an aldehyde.
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Affiliation(s)
- Rui Wang
- Division of Chemistry, Department of Biochemistry University of Texas Southwestern Medical Center 5323 Harry Hines Blvd., Dallas, Texas 75390-9038, USA.
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Powell WS, Rokach J. Biosynthesis, biological effects, and receptors of hydroxyeicosatetraenoic acids (HETEs) and oxoeicosatetraenoic acids (oxo-ETEs) derived from arachidonic acid. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:340-55. [PMID: 25449650 DOI: 10.1016/j.bbalip.2014.10.008] [Citation(s) in RCA: 218] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 10/10/2014] [Accepted: 10/21/2014] [Indexed: 12/14/2022]
Abstract
Arachidonic acid can be oxygenated by a variety of different enzymes, including lipoxygenases, cyclooxygenases, and cytochrome P450s, and can be converted to a complex mixture of oxygenated products as a result of lipid peroxidation. The initial products in these reactions are hydroperoxyeicosatetraenoic acids (HpETEs) and hydroxyeicosatetraenoic acids (HETEs). Oxoeicosatetraenoic acids (oxo-ETEs) can be formed by the actions of various dehydrogenases on HETEs or by dehydration of HpETEs. Although a large number of different HETEs and oxo-ETEs have been identified, this review will focus principally on 5-oxo-ETE, 5S-HETE, 12S-HETE, and 15S-HETE. Other related arachidonic acid metabolites will also be discussed in less detail. 5-Oxo-ETE is synthesized by oxidation of the 5-lipoxygenase product 5S-HETE by the selective enzyme, 5-hydroxyeicosanoid dehydrogenase. It actions are mediated by the selective OXE receptor, which is highly expressed on eosinophils, suggesting that it may be important in eosinophilic diseases such as asthma. 5-Oxo-ETE also appears to stimulate tumor cell proliferation and may also be involved in cancer. Highly selective and potent OXE receptor antagonists have recently become available and could help to clarify its pathophysiological role. The 12-lipoxygenase product 12S-HETE acts by the GPR31 receptor and promotes tumor cell proliferation and metastasis and could therefore be a promising target in cancer therapy. It may also be involved as a proinflammatory mediator in diabetes. In contrast, 15S-HETE may have a protective effect in cancer. In addition to GPCRs, higher concentration of HETEs and oxo-ETEs can activate peroxisome proliferator-activated receptors (PPARs) and could potentially regulate a variety of processes by this mechanism. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance".
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Affiliation(s)
- William S Powell
- Meakins-Christie Laboratories, Department of Medicine, McGill University, 3626St. Urbain Street, Montreal, Quebec H2X 2P2, Canada.
| | - Joshua Rokach
- Claude Pepper Institute and Department of Chemistry, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901, USA
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Issan Y, Hochhauser E, Guo A, Gotlinger KH, Kornowski R, Leshem-Lev D, Lev E, Porat E, Snir E, Thompson CI, Abraham NG, Laniado-Schwartzman M. Elevated level of pro-inflammatory eicosanoids and EPC dysfunction in diabetic patients with cardiac ischemia. Prostaglandins Other Lipid Mediat 2013; 100-101:15-21. [PMID: 23291334 DOI: 10.1016/j.prostaglandins.2012.12.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 12/13/2012] [Accepted: 12/14/2012] [Indexed: 11/16/2022]
Abstract
BACKGROUND Circulating endothelial progenitor cells (EPCs) are recruited from the blood system to sites of ischemia and endothelial damage, where they contribute to the repair and development of blood vessels. Since numerous eicosanoids including leukotrienes (LTs) and hydroxyeicosatetraenoic acids (HETEs) have been shown to exert potent pro-inflammatory activities, we examined their levels in chronic diabetic patients with severe cardiac ischemia in conjunction with the level and function of EPCs. RESULTS Lipidomic analysis revealed a diabetes-specific increase (p<0.05) in inflammatory and angiogenic eicosanoids including the 5-lipoxygenase-derived LTB (4.11±1.17 vs. 0.96±0.27 ng/ml), the lipoxygenase/CYP-derived 12-HETE (117.08±35.05 vs. 24.34±10.03 ng/ml), 12-HETrE (17.56±4.43 vs. 4.15±2.07 ng/ml), and the CYP-derived 20-HETE (0.32±0.04 vs. 0.06±0.05 ng/ml) the level of which correlated with BMI (p=0.0027). In contrast, levels of the CYP-derived EETs were not significantly (p=0.36) different between these two groups. EPC levels and their colony-forming units were lower (p<0.05) with a reduced viability in diabetic patients compared with non-diabetics. EPC function (colony-forming units (CFUs) and MTT assay) also negatively correlated with the circulating levels of HgA1C. CONCLUSION This study demonstrates a close association between elevated levels of highly pro-inflammatory eicosonoids, diabetes and EPC dysfunction in patients with cardiac ischemia, indicating that chronic inflammation impact negatively on EPC function and angiogenic capacity in diabetes.
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Affiliation(s)
- Yossi Issan
- Cardiac Research Laboratory at the Felsenstein Medical Research Institute, Rabin Medical Center, Petah-Tikva and the Sackler Faculty of Medicine, Tel-Aviv University, Israel
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Overexpression of miR-221 is associated with aggressive clinicopathologic characteristics and the BRAF mutation in papillary thyroid carcinomas. Med Oncol 2012; 29:3360-6. [PMID: 22855362 DOI: 10.1007/s12032-012-0315-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 07/16/2012] [Indexed: 01/24/2023]
Abstract
Correlation between clinicopathogenetic features and the expression of specific miRNAs is unclear in papillary thyroid carcinoma (PTC). We therefore sought to assess whether miR-221 was associated with aggressive clinicopathologic characteristics and the BRAF mutation. We studied the expression levels of miR-221 using northern blot quantitated by scion image in 51 cases of PTCs. The status of BRAF of PTCs was analyzed through direct DNA sequencing. Mann-Whitney U test was used to analyze different expression of miR-221 in PTCs with distinct clinicopathogenetic characteristics including gender, age, tumor size, multifocality, extrathyroidal invasion, disease stages, node metastasis, and BRAF status. Compared with the normal thyroid tissues, the relative expression of miR-221 in tumor tissues was significantly upregulated (p < 0.001). Overexpression of miR-221 was significantly associated with extrathyroidal invasion (p = 0.001), lymph node metastasis (p = 0.046), advanced disease stages III-IV (p = 0.001), and the BRAF mutation (p = 0.014). While among BRAF wild tumors, miR-221 was only associated with extarthyroidal invasion, it showed strong association with all above aggressive features among BRAF mutation tumors. MiR-221 may be of potential importance in determining the aggressive properties of PTCs including the BRAF mutation, and it may further refine the risk stratification by BRAF mutation in PTCs.
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12
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Angiogenesis: the HETE is on. Blood 2012; 118:5367-9. [PMID: 22096255 DOI: 10.1182/blood-2011-09-376152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In this issue of Blood, Singh and colleagues identify HMG-CoA reductase-dependent farnesylation of Rac-1 as critical for 15(S)-HETE-induced angiogenesis. These findings establish a novel link between eicosanoid and cholesterol metabolism with important biologic and therapeutic implications for angiogenesis.
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13
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Gentile LB, Piva B, Diaz BL. Hypertonic stress induces VEGF production in human colon cancer cell line Caco-2: inhibitory role of autocrine PGE₂. PLoS One 2011; 6:e25193. [PMID: 21980393 PMCID: PMC3182186 DOI: 10.1371/journal.pone.0025193] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 08/30/2011] [Indexed: 12/27/2022] Open
Abstract
Vascular Endothelial Growth Factor (VEGF) is a major regulator of angiogenesis. VEGF expression is up regulated in response to micro-environmental cues related to poor blood supply such as hypoxia. However, regulation of VEGF expression in cancer cells is not limited to the stress response due to increased volume of the tumor mass. Lipid mediators in particular arachidonic acid-derived prostaglandin (PG)E2 are regulators of VEGF expression and angiogenesis in colon cancer. In addition, increased osmolarity that is generated during colonic water absorption and feces consolidation seems to activate colon cancer cells and promote PGE2 generation. Such physiological stimulation may provide signaling for cancer promotion. Here we investigated the effect of exposure to a hypertonic medium, to emulate colonic environment, on VEGF production by colon cancer cells. The role of concomitant PGE2 generation and MAPK activation was addressed by specific pharmacological inhibition. Human colon cancer cell line Caco-2 exposed to a hypertonic environment responded with marked VEGF and PGE2 production. VEGF production was inhibited by selective inhibitors of ERK 1/2 and p38 MAPK pathways. To address the regulatory role of PGE2 on VEGF production, Caco-2 cells were treated with cPLA2 (ATK) and COX-2 (NS-398) inhibitors, that completely block PGE2 generation. The Caco-2 cells were also treated with a non selective PGE2 receptor antagonist. Each treatment significantly increased the hypertonic stress-induced VEGF production. Moreover, addition of PGE2 or selective EP2 receptor agonist to activated Caco-2 cells inhibited VEGF production. The autocrine inhibitory role for PGE2 appears to be selective to hypertonic environment since VEGF production induced by exposure to CoCl2 was decreased by inhibition of concomitant PGE2 generation. Our results indicated that hypertonicity stimulates VEGF production in colon cancer cell lines. Also PGE2 plays an inhibitory role on VEGF production by Caco-2 cells exposed to hyperosmotic stress through EP2 activation.
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Affiliation(s)
- Luciana B. Gentile
- Divisão de Biologia Celular, Coordenação de Pesquisa, Instituto Nacional de Câncer, Rio de Janeiro, Rio de Janeiro, Brasil
- Programa de Pós-Graduação em Ciências Morfológicas, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brasil
| | - Bruno Piva
- Programa de Imunobiologia, Instituto de Biofísica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brasil
| | - Bruno L. Diaz
- Programa de Imunobiologia, Instituto de Biofísica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brasil
- * E-mail:
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12/15-Lipoxygenase gene knockout severely impairs ischemia-induced angiogenesis due to lack of Rac1 farnesylation. Blood 2011; 118:5701-12. [PMID: 21841162 DOI: 10.1182/blood-2011-04-347468] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
To understand the mechanisms by which 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE) activates Rac1 in the induction of angiogenesis, we studied the role of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase and αPix. 15(S)-HETE stimulated Rac1 in a sustained manner in human dermal microvascular endothelial cells (HDMVECs). Simvastatin, a potent inhibitor of HMG-CoA reductase, suppressed 15(S)-HETE-induced Rac1 activation in HDMVECs affecting their migration and tube formation. 15(S)-HETE by inducing HMG-CoA reductase expression caused increased farnesylation and membrane translocation of Rac1 where it became activated by Src-dependent αPix stimulation. Mevalonate rescued 15(S)-HETE-induced Rac1 farnesylation and membrane translocation in HDMVECs and the migration and tube formation of these cells from inhibition by simvastatin. Down-regulation of αPix inhibited 15(S)-HETE-induced HDMVEC migration and tube formation. Hind-limb ischemia induced Rac1 farnesylation and activation leading to increased angiogenesis and these effects were blocked by simvastatin and rescued by mevalonate in WT mice. In contrast, hind-limb ischemia failed to induce Rac1 farnesylation and activation as well as angiogenic response in 12/15-Lox(-/-) mice. Activation of Src and αPix were also compromised at least to some extent in 12/15-Lox(-/-) mice compared with WT mice in response to hind-limb ischemia. Together, these findings demonstrate for the first time that HMG-CoA reductase plays a determinant role in 12/15-Lox-induced angiogenesis.
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15
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Tian H, Lu Y, Shah SP, Hong S. 14S,21R-dihydroxydocosahexaenoic acid remedies impaired healing and mesenchymal stem cell functions in diabetic wounds. J Biol Chem 2010; 286:4443-53. [PMID: 21112969 DOI: 10.1074/jbc.m110.100388] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Treatment of diabetes-impaired wound healing remains a major unresolved medical challenge. Here, we identified suppressed formation of a novel reparative lipid mediator 14S,21R-dihydroxydocosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid (14S,21R-diHDHA) in cutaneous wounds of diabetic db/db mice. These results indicate that diabetes impedes the biosynthetic pathways of 14S,21R-diHDHA in skin wounds. Administration of exogenous 14S,21R-diHDHA to wounds in diabetic animals rescued healing and angiogenesis. When db/db mesenchymal stem cells (MSCs) were administered together with 14S,21R-diHDHA to wounds in diabetic animals, they coacted to accelerate wound re-epithelialization, granulation tissue formation, and synergistically improved vascularization. In the pivotal cellular processes of angiogenesis, 14S,21R-diHDHA enhanced VEGF release, vasculature formation, and migration of db/db dermal microvascular endothelial cells (DMVECs), as well as remedied paracrine angiogenic functions of db/db MSCs, including VEGF secretion and the promotion of DMVEC migration and vasculature formation. Our results show that 14S,21R-diHDHA activates the p38 MAPK pathway in wounds, db/db MSCs, and DMVECs. Overall, the impeded formation of 14S,21R-diHDHA described in this study suggests that diabetes could affect the generation of pro-healing lipid mediators in wound healing. By restoring wound healing and MSC functions, 14S,21R-diHDHA is a new lead for the development of better therapeutics used in treating wounds of diabetics.
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Affiliation(s)
- Haibin Tian
- Center of Neuroscience Excellence, Louisiana State University Health Science Center, New Orleans, Louisiana 70112, USA
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16
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Arachidonic acid promotes epithelial-to-mesenchymal-like transition in mammary epithelial cells MCF10A. Eur J Cell Biol 2010; 89:476-88. [PMID: 20207443 DOI: 10.1016/j.ejcb.2009.12.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 12/19/2009] [Accepted: 12/21/2009] [Indexed: 11/22/2022] Open
Abstract
Epidemiological studies and animal models suggest an association between high levels of dietary fat intake and an increased risk of breast cancer. Cancer progression requires the development of metastasis, which is characterized by an increase in cell motility and invasion. Epithelial-to-mesenchymal transition (EMT) is a process, by which epithelial cells are transdifferentiated to a more mesenchymal state. A similar process takes place during tumor progression, when carcinoma cells stably or transiently lose epithelial polarities and acquire a mesenchymal phenotype. Arachidonic acid (AA) is a fatty acid that mediates cellular processes, such as cell survival, angiogenesis, chemotaxis, mitogenesis, migration and apoptosis. However, the role of AA on the EMT process in human mammary epithelial cells remains to be studied. We demonstrate here that AA promotes an increase in vimentin and N-cadherin expression, MMP-9 secretion, a decrease in E-cadherin junctional levels, and the activation of FAK, Src and NF-kappaB in MCF10A cells. Furthermore, AA also promotes cell migration in an Src kinase activity-dependent fashion. In conclusion, our results demonstrate, for the first time, that AA promotes an epithelial-to-mesenchymal-like transition in MCF10A human mammary non-tumorigenic epithelial cells.
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17
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PKCα-MAPK/ERK-phospholipase A2 signaling is required for human melanoma-enhanced brain endothelial cell proliferation and motility. Microvasc Res 2009; 78:338-57. [DOI: 10.1016/j.mvr.2009.09.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2008] [Revised: 07/08/2009] [Accepted: 09/01/2009] [Indexed: 12/28/2022]
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18
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Lu Y, Tian H, Hong S. Novel 14,21-dihydroxy-docosahexaenoic acids: structures, formation pathways, and enhancement of wound healing. J Lipid Res 2009; 51:923-32. [PMID: 19965612 DOI: 10.1194/jlr.m000059] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Chronic wounds remain a medical challenge, where well-coordinated cellular and molecular processes required by optimal healing are impaired by diabetes, aging, or other diseases. In determining mechanisms that regulate wound healing, we found that wounding induced formation of novel endogenous 14S,21S-dihydroxy-docosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acids (14S,21S-diHDHA);14R,21R-diHDHA; 14S,21R-diHDHA; and/or 14R,21S-diHDHA. 12-lipoxygenase and cytochrome P450 catalysis in tandem converted docosahexaenoic acid to 14S,21R-diHDHA and 14S,21S-diHDHA through the intermediacy of 14S-HDHA; P450 also converted 14R-HDHA to novel 14R,21R-diHDHA and 14R,21S-diHDHA. Macrophages function as the combination of 12-lipoxgenase and P450 to generate these 14,21-diHDHA stereoisomers, as well as their intermediates 14S-HDHA, 14R-HDHA, and 21-HDHA. The structure and formation pathways of 14,21-diHDHA stereoisomers were further confirmed by macrophage biosynthesis of 14,21-diHDHA-21,22,22,22-d(4) stereoisomers, 14S-HDHA-d(5), 14R-HDHA-d(5), and 21-HDHA-d(4) from DHA-21,21,22,22,22-d(5). We found that 14S,21-diHDHA and 14R,21-diHDHA enhanced wound closure, reepithelialization, granulation tissue growth, and capillary vasculature formation of murine wounds. 14S,21-diHDHA and 14R,21-diHDHA produced by macrophages may partially represent the molecular mechanisms for macrophage pro-healing function. Taken together, 14,21-dihydroxy-DHA stereoisomers and their formation pathways may represent a novel mechanism in the orchestration of wound healing processes, which may provide new insight for developing novel therapeutic modalities that counteract impairments to wound healing.
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Affiliation(s)
- Yan Lu
- Center of Neuroscience Excellence, Health Science Center, Louisiana State University, New Orleans, LA 70112, USA
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19
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Bellner L, Martinelli L, Halilovic A, Patil K, Puri N, Dunn MW, Regan RF, Schwartzman ML. Heme oxygenase-2 deletion causes endothelial cell activation marked by oxidative stress, inflammation, and angiogenesis. J Pharmacol Exp Ther 2009. [PMID: 19773531 DOI: 10.1124/jpet.109.15835] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In previous studies, we have shown that heme oxygenase (HO)-2 null [HO-2(-/-)] mice exhibit a faulty response to injury; chronic inflammation and massive neovascularization replaced resolution of inflammation and tissue repair. Endothelial cells play an active and essential role in the control of inflammation and the process of angiogenesis. We examined whether HO-2 deletion affects endothelial cell function. Under basal conditions, HO-2(-/-) aortic endothelial cells (mAEC) showed a 3-fold higher expression of vascular endothelial growth factor receptor 1 and a marked angiogenic response compared with wild-type (WT) cells. Compared with WT cells, HO-2(-/-) mAEC showed a 2-fold reduction in HO activity and marked increases in levels of gp91(phox)/NADPH oxidase isoform, superoxide, nuclear factor kappaB activation, and expression of inflammatory cytokines, including interleukin (IL)-1alpha and IL-6. HO-2 deletion transforms endothelial cells from a "normal" to an "activated" phenotype characterized by increases in inflammatory, oxidative, and angiogenic factors. This switch may be the result of reduced HO activity and the associated reduction in the cytoprotective HO products, carbon monoxide and biliverdin/bilirubin, because addition of biliverdin to HO-2(-/-) cells attenuated angiogenesis and reduced superoxide production. This transformation underscores the importance of HO-2 in the regulation of endothelial cell homeostasis.
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Affiliation(s)
- Lars Bellner
- Department of Pharmacology, New York Medical College, Valhalla, New York 10595, USA
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20
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Bellner L, Martinelli L, Halilovic A, Patil K, Puri N, Dunn MW, Regan RF, Schwartzman ML. Heme oxygenase-2 deletion causes endothelial cell activation marked by oxidative stress, inflammation, and angiogenesis. J Pharmacol Exp Ther 2009; 331:925-32. [PMID: 19773531 DOI: 10.1124/jpet.109.158352] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In previous studies, we have shown that heme oxygenase (HO)-2 null [HO-2(-/-)] mice exhibit a faulty response to injury; chronic inflammation and massive neovascularization replaced resolution of inflammation and tissue repair. Endothelial cells play an active and essential role in the control of inflammation and the process of angiogenesis. We examined whether HO-2 deletion affects endothelial cell function. Under basal conditions, HO-2(-/-) aortic endothelial cells (mAEC) showed a 3-fold higher expression of vascular endothelial growth factor receptor 1 and a marked angiogenic response compared with wild-type (WT) cells. Compared with WT cells, HO-2(-/-) mAEC showed a 2-fold reduction in HO activity and marked increases in levels of gp91(phox)/NADPH oxidase isoform, superoxide, nuclear factor kappaB activation, and expression of inflammatory cytokines, including interleukin (IL)-1alpha and IL-6. HO-2 deletion transforms endothelial cells from a "normal" to an "activated" phenotype characterized by increases in inflammatory, oxidative, and angiogenic factors. This switch may be the result of reduced HO activity and the associated reduction in the cytoprotective HO products, carbon monoxide and biliverdin/bilirubin, because addition of biliverdin to HO-2(-/-) cells attenuated angiogenesis and reduced superoxide production. This transformation underscores the importance of HO-2 in the regulation of endothelial cell homeostasis.
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Affiliation(s)
- Lars Bellner
- Department of Pharmacology, New York Medical College, Valhalla, New York 10595, USA
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21
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A new antiangiogenic C24 oxylipin from the soft coral Sinularia numerosa. Bioorg Med Chem 2009; 17:2181-4. [DOI: 10.1016/j.bmc.2008.10.083] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Revised: 09/20/2008] [Accepted: 10/31/2008] [Indexed: 11/22/2022]
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22
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Seta F, Patil K, Bellner L, Mezentsev A, Kemp R, Dunn MW, Schwartzman ML. Inhibition of VEGF expression and corneal neovascularization by siRNA targeting cytochrome P450 4B1. Prostaglandins Other Lipid Mediat 2007; 84:116-27. [PMID: 17991614 DOI: 10.1016/j.prostaglandins.2007.05.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Revised: 05/01/2007] [Accepted: 05/06/2007] [Indexed: 11/17/2022]
Abstract
Injury to the cornea leads to formation of mediators that initiate and amplify inflammatory responses and neovascularization. Among these are lipid mediators generated by a cytochrome P450 (CYP) enzyme identified as CYP4B1. Increased corneal CYP4B1 expression increases limbal angiogenic activity through the production of 12-hydroxyeicosatrienoic acid (12-HETrE), a potent inflammatory and angiogenic eicosanoid. We used siRNA duplexes targeting CYP4B1 to substantiate the link between CYP4B1 expression, 12-HETrE production and angiogenesis in a model of suture-induced corneal neovascularization. Intrastromal sutures induced a time-dependent neovascular response which was significantly attenuated by CYP4B1-specific siRNAs but not by nonspecific siRNA. CYP4B1 mRNA was reduced by 60% and 12-HETrE's levels were barely detected in corneal homogenates from eyes treated with the CYP4B1-specific siRNA. The decreased neovascular response in CYP4B1 siRNA-treated eyes was associated with a 75% reduction in corneal VEGF mRNA levels. Transfection of rabbit corneal epithelial cells with CYP4B1 cDNA induced VEGF expression. Conversely, treatment with CYP4B1 siRNA or addition of a CYP4B1 inhibitor significantly decreased VEGF mRNA levels; addition of 12-HETrE potently increased them. The results strongly implicate the corneal CYP4B1 as a component of the inflammatory and neovascular cascade initiated by injury and further suggest that CYP4B1-12-HETrE is a proximal regulator of VEGF expression.
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Affiliation(s)
- Francesca Seta
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, USA
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23
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Seta F, Bellner L, Rezzani R, Regan RF, Dunn MW, Abraham NG, Gronert K, Laniado-Schwartzman M. Heme oxygenase-2 is a critical determinant for execution of an acute inflammatory and reparative response. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 169:1612-23. [PMID: 17071585 PMCID: PMC1780218 DOI: 10.2353/ajpath.2006.060555] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/20/2006] [Indexed: 01/09/2023]
Abstract
Heme oxygenase (HO) represents an intrinsic anti-inflammatory system based on its ability to regulate leukocyte function and inhibit expression of proinflammatory cytokines. This anti-inflammatory function is linked to the inducible isoform HO-1; the role of the constitutive isoform HO-2 is unknown. The current study was undertaken to investigate the role of HO-2 in the regulation of the acute inflammatory and reparative response by using HO-2-null mice and well-established animal models of epithelial injury and antigen-induced peritonitis. Here we show that in vivo deletion of HO-2 disables execution of the acute inflammatory and reparative response after epithelial injury and leads to an exaggerated inflammatory response in antigen-induced peritonitis. HO-2 deletion was associated with impaired HO-1 induction, indicating that HO-2 is critical for HO-1 expression and that the subsequent failure to up-regulate the HO system may contribute to unresolved inflammation and the development of chronic inflammatory conditions. Indeed, supplementation with the HO bioactive product, biliverdin, rescued the acute inflammatory and reparative response in HO-2-null mice. Thus, HO-2 sets in place a basal tone of anti-inflammatory signals that may be a prerequisite for the ordered execution of an inflammatory and reparative response.
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Affiliation(s)
- Francesca Seta
- Department of Pharmacology, New York Medical College, Grassland Reservation, Valhalla, NY 10595, USA
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24
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Dronadula N, Rizvi F, Blaskova E, Li Q, Rao GN. Involvement of cAMP-response element binding protein-1 in arachidonic acid-induced vascular smooth muscle cell motility. J Lipid Res 2005; 47:767-77. [PMID: 16382163 DOI: 10.1194/jlr.m500369-jlr200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In addition to their role in many vital cellular functions, arachidonic acid (AA) and its eicosanoid metabolites are involved in the pathogenesis of several diseases, including atherosclerosis and cancer. To understand the potential mechanisms by which these lipid molecules could influence the disease processes, particularly cardiovascular diseases, we studied AA's effects on vascular smooth muscle cell (VSMC) motility and the role of cAMP-response element binding protein-1 (CREB-1) in this process. AA exerted differential effects on VSMC motility; at lower doses, it stimulated motility, whereas at higher doses, it was inhibitory. AA-induced VSMC motility requires its conversion via the lipoxygenase (LOX) and cyclooxygenase (COX) pathways. AA stimulated the phosphorylation of extracellular signal-regulated kinases (ERKs), Jun N-terminal kinases (JNKs), and p38 mitogen-activated protein kinase (p38MAPK) in a time-dependent manner, and blockade of these serine/threonine kinases significantly attenuated AA-induced VSMC motility. In addition, AA stimulated CREB-1 phosphorylation and activity in a manner that was also dependent on its metabolic conversion via the LOX and COX pathways and the activation of ERKs and p38MAPK but not JNKs. Furthermore, suppression of CREB-1 activation inhibited AA-induced VSMC motility. 15(S)-Hydroxyeicosatetraenoic acid and prostaglandin F2alpha, the 15-LOX and COX metabolites of AA, respectively, that are produced by VSMC at lower doses, were also found to stimulate motility in these cells. Together, these results suggest that AA induces VSMC motility by complex mechanisms involving its metabolism via the LOX and COX pathways as well as the ERK- and p38MAPK-dependent and JNK-independent activation of CREB-1.
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MESH Headings
- Animals
- Arachidonic Acid/metabolism
- Arachidonic Acid/pharmacology
- Cell Movement/drug effects
- Cell Movement/physiology
- Cells, Cultured
- Cyclic AMP Response Element-Binding Protein/genetics
- Cyclic AMP Response Element-Binding Protein/metabolism
- Cytochrome P-450 Enzyme System/metabolism
- Dinoprost/metabolism
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Genes, Reporter
- Hydroxyeicosatetraenoic Acids/metabolism
- JNK Mitogen-Activated Protein Kinases/metabolism
- Lipoxygenase/metabolism
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Prostaglandin-Endoperoxide Synthases/metabolism
- Rats
- Rats, Sprague-Dawley
- Signal Transduction/physiology
- p38 Mitogen-Activated Protein Kinases/metabolism
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Affiliation(s)
- Nagadhara Dronadula
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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25
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Zhang B, Cao H, Rao GN. Fibroblast growth factor-2 is a downstream mediator of phosphatidylinositol 3-kinase-Akt signaling in 14,15-epoxyeicosatrienoic acid-induced angiogenesis. J Biol Chem 2005; 281:905-14. [PMID: 16286479 DOI: 10.1074/jbc.m503945200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To determine the efficacy of cytochrome P450 2C9 metabolites of arachidonic acid, viz. 5,6-, 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acids (EETs), in inducing angiogenesis, we have studied their effects on human dermal microvascular endothelial cell (HDMVEC) tube formation and migration. All four EETs stimulated HDMVEC tube formation and migration in a dose-dependent manner. Because 14,15-EET was found to be slightly more efficacious than 5,6-, 8,9-, and 11,12-EETs in stimulating HDMVEC tube formation and migration, we next focused on elucidation of the signaling mechanisms underlying its angiogenic activity. 14,15-EET stimulated Akt and S6K1 phosphorylation in Src- and phosphatidylinositol 3-kinase (PI3K)-dependent manner in HDMVECs. Inhibition of Src and PI3K-Akt-mTOR signaling by both pharmacological and dominant-negative mutant approaches suppressed 14,15-EET-induced HDMVEC tube formation and migration in vitro and Matrigel plug angiogenesis in vivo. In addition, 14,15-EET induced the expression of fibroblast growth factor-2 (FGF-2) in Src- and PI3K-Akt-dependent and mTOR-independent manner in HDMVECs. Neutralizing anti-FGF-2 antibodies completely suppressed 14,15-EET-induced HDMVEC tube formation and migration in vitro and Matrigel plug angiogenesis in vivo. Together, these results show for the first time that Src and PI3K-Akt signaling via targeting in parallel with FGF-2 expression and mTOR-S6K1 activation plays an indispensable role in 14,15-EET-induced angiogenesis.
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MESH Headings
- 8,11,14-Eicosatrienoic Acid/analogs & derivatives
- 8,11,14-Eicosatrienoic Acid/pharmacology
- Animals
- Cell Movement
- Cells, Cultured
- Collagen/chemistry
- Collagen/pharmacology
- Dose-Response Relationship, Drug
- Drug Combinations
- Endothelium, Vascular/cytology
- Fibroblast Growth Factor 2/metabolism
- Fibroblast Growth Factor 2/physiology
- Genetic Vectors
- Green Fluorescent Proteins/metabolism
- Humans
- Laminin/chemistry
- Laminin/pharmacology
- Mice
- Mice, Inbred C57BL
- Microcirculation
- Neovascularization, Pathologic
- Oxygen/chemistry
- Phosphatidylinositol 3-Kinases/metabolism
- Phosphorylation
- Protein Kinases/metabolism
- Proteoglycans/chemistry
- Proteoglycans/pharmacology
- Proto-Oncogene Proteins c-akt/metabolism
- RNA, Messenger/metabolism
- Ribosomal Protein S6 Kinases, 70-kDa/metabolism
- Signal Transduction
- TOR Serine-Threonine Kinases
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Affiliation(s)
- Baolin Zhang
- Department of Physiology, University of Tennessee Health Science Center, Memphis, 38163, USA
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26
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Zhang B, Cao H, Rao GN. 15(S)-hydroxyeicosatetraenoic acid induces angiogenesis via activation of PI3K-Akt-mTOR-S6K1 signaling. Cancer Res 2005; 65:7283-91. [PMID: 16103079 DOI: 10.1158/0008-5472.can-05-0633] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To determine whether the lipoxygenase metabolites of arachidonic acid, 5(S)-, 12(S)-, and 15(S)-hydroxyeicosatetraenoic acids [5(S)-HETE, 12(S)-HETE, and 15(S)-HETE, respectively] are angiogenic, we have studied their effects on human dermal microvascular endothelial cell (HDMVEC) tube formation and migration. All three HETEs stimulated HDMVEC tube formation and migration. Because 15(S)-HETE was found to be more potent than 5(S)-HETE and 12(S)-HETE in HDMVEC tube formation, we next focused on elucidation of the signaling mechanisms underlying its angiogenic activity. 15(S)-HETE stimulated Akt and S6K1 phosphorylation in HDMVEC in a time-dependent manner. Wortmannin and LY294002, two specific inhibitors of phosphatidylinositol 3-kinase (PI3K), blocked both Akt and S6K1 phosphorylation, whereas rapamycin, a specific inhibitor of Akt downstream effector, mammalian target of rapamycin (mTOR), suppressed only S6K1 phosphorylation induced by 15(S)-HETE suggesting that this eicosanoid activates the PI3K-Akt-mTOR-S6K1 signaling in HDMVEC. Wortmannin, LY294002, and rapamycin also inhibited 15(S)-HETE-induced HDMVEC tube formation and migration. In addition, all three HETEs stimulated angiogenesis as measured by in vivo Matrigel plug assay with 15(S)-HETE being more potent. Pharmacologic inhibition of PI3K-Akt-mTOR-S6K1 signaling completely suppressed 15(S)-HETE-induced in vivo angiogenesis. Consistent with these observations, adenoviral-mediated expression of dominant-negative Akt also blocked 15(S)-HETE-induced HDMVEC tube formation and migration and in vivo angiogenesis. Together, these results show for the first time that 15(S)-HETE stimulates angiogenesis via activation of PI3K-Akt-mTOR-S6K1 signaling.
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Affiliation(s)
- Baolin Zhang
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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27
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Mezentsev A, Mastyugin V, Seta F, Ashkar S, Kemp R, Reddy DS, Falck JR, Dunn MW, Laniado-Schwartzman M. Transfection of Cytochrome P4504B1 into the Cornea Increases Angiogenic Activity of the Limbal Vessels. J Pharmacol Exp Ther 2005; 315:42-50. [PMID: 16009741 DOI: 10.1124/jpet.105.088211] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Injury to the ocular surface induces the production of the corneal epithelial-derived 12-hydroxyeicosatetrienoic acid (12-HETrE), which exhibits stereospecific potent inflammatory and angiogenic properties and is formed by a cytochrome P450 (P450) enzyme, CYP4B1. We have cloned the rabbit corneal CYP4B1 into the expression plasmid pIRES2-enhanced green fluorescent protein (EGFP) and examined the effect of CYP4B1 overexpression on corneal inflammation in vivo and limbal vessel sprouting ex vivo. Cultured rabbit corneal epithelial cells transfected with pIRES2-EGFP-CYP4B1 metabolized arachidonic acid to 12-HETrE at a rate five times higher than that of pIRES2-EGFP-transfected cells (3.53 +/- 0.08 versus 0.62 +/- 0.10 nmol/h/10(6) cells; mean +/- S.E.M., n = 6, p < 0.05), indicating a functional expression of the CYP4B1. Injection of either plasmid into the rabbit cornea resulted in EGFP fluorescence in the corneal epithelium. However, corneal neovascularization, as measured by the length of penetrating blood vessels, was significantly greater in the corneas of eyes transfected with the pIRES2-CYP4B1 compared with pIRES2-EGFP. Corneal-limbal explants from eyes transfected with pIRES2-CYP4B1 showed a marked angiogenic activity (46 +/- 10 versus 12 +/- 3 mm capillary length, n = 6, p < 0.05), which correlated with increased levels of 12-HETrE, the CYP4B1-derived angiogenic 12-hydroxyeicosanoid (0.93 +/- 0.18 versus 0.15 +/- 0.02 pmol/explant, n = 6, p < 0.05), and was inhibited (76 +/- 5%) by the P450 inhibitor 17-octadecynoic acid. The results further implicate the corneal CYP4B1 as a component of the inflammatory and angiogenic cascade initiated by injury to the ocular surface and raise the possibility of a new therapeutic target for preventing corneal neovascularization, namely, the CYP4B1-12-HETrE system.
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Affiliation(s)
- Alexandre Mezentsev
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, USA
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28
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Dronadula N, Liu Z, Wang C, Cao H, Rao GN. STAT-3-dependent cytosolic phospholipase A2 expression is required for thrombin-induced vascular smooth muscle cell motility. J Biol Chem 2004; 280:3112-20. [PMID: 15548519 DOI: 10.1074/jbc.m409739200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Vascular smooth muscle cell (VSMC) migration from media to intima and its multiplication in intima is a contributing factor in the pathogenesis of atherosclerosis and restenosis after angioplasty. Previously, we have demonstrated that STAT-3-dependent cytosolic phospholipase A(2) (cPLA(2)) expression is needed for VSMC motility induced by platelet-derived growth factor-BB, a receptor tyrosine kinase agonist (Neeli et al. (2005) J. Biol. Chem. 279, 46122-46128). In order to learn more about the STAT-3-cPLA(2) axis in motogenic signaling, here we have studied its role in VSMC motility in response to a G protein-coupled receptor (GPCR) agonist, thrombin. Thrombin induced VSMC motility in a dose-dependent manner with a maximum effect at 0.5 units/ml. Thrombin activated STAT-3 as measured by its tyrosine phosphorylation and translocation from the cytoplasm to the nucleus. Forced expression of a dominant negative mutant of STAT-3 reduced thrombin-induced STAT-3 tyrosine phosphorylation and its translocation from the cytoplasm to the nucleus. Thrombin stimulated STAT-3-DNA binding and reporter gene activities in VSMC, and these responses were blocked by FS3DM, a dominant negative mutant of STAT-3. FS3DM also attenuated thrombin-induced VSMC motility. Thrombin induced the expression of cPLA(2) in a time- and STAT-3-dependent manner. In addition, pharmacological inhibition of cPLA(2) blocked thrombin-induced VSMC motility. Furthermore, exogenous addition of arachidonic acid rescued thrombin-induced VSMC motility from inhibition by blockade of STAT-3 activation. Forced expression of cPLA(2) also surpassed the inhibitory effect of dominant negative STAT-3 on thrombin-induced VSMC motility. Together, these results show that thrombin-induced VSMC motility requires STAT-3-dependent induction of expression of cPLA(2).
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Affiliation(s)
- Nagadhara Dronadula
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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Neeli I, Liu Z, Dronadula N, Ma ZA, Rao GN. An essential role of the Jak-2/STAT-3/cytosolic phospholipase A(2) axis in platelet-derived growth factor BB-induced vascular smooth muscle cell motility. J Biol Chem 2004; 279:46122-8. [PMID: 15322111 DOI: 10.1074/jbc.m406922200] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Platelet-derived growth factor-BB (PDGF-BB) is a potent motogen for vascular smooth muscle cells (VSMCs). To understand its motogenic signaling events, we have studied the role of the Janus-activated kinase/signal transducers and activators of transcription (Jak/STAT) pathway and cytosolic phospholipase A(2) (cPLA(2)). PDGF-BB stimulated tyrosine phosphorylation of Jak-2 and STAT-3 in a time-dependent manner in VSMCs. In addition, AG490 and Jak-2KEpRK5, a selective pharmacological inhibitor and a dominant negative mutant, respectively, of Jak-2, attenuated PDGF-BB-induced STAT-3 tyrosine phosphorylation and its DNA binding and reporter gene activities. PDGF-BB induced VSMC motility in a dose-dependent manner with a maximum effect at 10 ng/ml. Dominant negative mutant-dependent suppression of Jak-2 and STAT-3 blocked PDGF-BB-induced VSMC motility. PDGF-BB induced the expression of cPLA(2) in a Jak-2/STAT-3-dependent manner, and pharmacological inhibitors of cPLA(2) prevented PDGFBB-induced VSMC motility. Furthermore, either exogenous addition of arachidonic acid or forced expression of cPLA(2) rescued PDGF-BB-induced VSMC motility from inhibition by blockade of Jak-2 and STAT-3 activation. Together, these results for the first time show that PDGF-BB-induced VSMC motility requires activation of the Jak-2/STAT-3/cPLA(2) signaling axis.
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Affiliation(s)
- Indira Neeli
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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Jiang M, Mezentsev A, Kemp R, Byun K, Falck JR, Miano JM, Nasjletti A, Abraham NG, Laniado-Schwartzman M. Smooth muscle--specific expression of CYP4A1 induces endothelial sprouting in renal arterial microvessels. Circ Res 2003; 94:167-74. [PMID: 14670847 DOI: 10.1161/01.res.0000111523.12842.fc] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Cytochrome P450 (CYP) 4A1 has been characterized as the most efficient arachidonic acid omega-hydroxylase catalyzing the formation of 20-hydroxyeicosatetraenoic acid (20-HETE), a potent constrictor of the renal and cerebral microcirculation and a mitogen for smooth muscle cells. We constructed adenoviruses expressing the CYP4A1 cDNA or LacZ under the control of the smooth muscle cell-specific promoter SM22alpha (Ad-SM22-4A1 and Ad-SM22-nLacZ, respectively). Beta-galactosidase expression was detected in Ad-SM22-nLacZ-transduced vascular smooth muscle A7r5 and PAC1 cells, but not in Ad-SM22-nLacZ-transduced 3T3 fibroblasts or vascular endothelial cells. Likewise, CYP4A1 mRNA and protein were detected in Ad-SM22-4A1-transduced A7r5 and PAC1 cells. Ad-SM22-4A1-transduced A7r5 cells metabolized lauric acid to 12-hydroxy-lauric acid at a rate 5 times greater than that of cells transduced with Ad-SM22-nLacZ (4.79+/-1.77 versus 0.97+/-0.57 nmol 12-hydroxy lauric acid/10(6) cells per h). Smooth muscle-specific LacZ expression was also detected in microdissected renal interlobar arteries transduced with Ad-SM22-nLacZ. Arteries transduced with Ad-SM22-4A1 produced higher levels of 20-HETE (4.04+/-0.29 and 13.43+/-2.84 ng/mg protein in Ad-SM22-nLacZ-transduced and Ad-SM22-4A1-transduced arteries, respectively) and demonstrated a marked angiogenic activity measured as the total length of sprouting neovessels (12.63+/-3.66 mm in Ad-SM22-4A1-transduced vessels versus 1.79+/-0.89 mm in Ad-SM22-nLacZ-transduced vessels). This angiogenic activity represented endothelial cell sprouting and was fully blocked by treatment with HET0016, a selective inhibitor of CYP4A-catalyzed reactions. The inhibitory effect of HET0016 was reversed by addition of a 20-HETE agonist. We conclude that Ad-SM22-4A1 drives a smooth muscle-specific functional expression of CYP4A1 and demonstrates increased angiogenesis, presumably via increased production of 20-HETE.
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Affiliation(s)
- Miao Jiang
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, USA
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31
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Neeli I, Yellaturu CR, Rao GN. Arachidonic acid activation of translation initiation signaling in vascular smooth muscle cells. Biochem Biophys Res Commun 2003; 309:755-61. [PMID: 13679036 DOI: 10.1016/j.bbrc.2003.08.066] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
To understand the role of arachidonic acid (AA) in regulating vascular smooth muscle cell (VSMC) growth, its effects on phosphorylation of Akt, S6K1, ribosomal protein S6, 4EBP1, and eIF4E were studied. Arachidonic acid stimulated phosphorylation of Akt, S6K1, ribosomal protein S6, 4EBP1, and eIF4E in a time-dependent manner in VSMC. Arachidonic acid stimulation of phosphorylation of the above signaling molecules is specific, as these events were not affected by other unsaturated or saturated fatty acids. Metabolic conversion of AA via the LOX/MOX and/or COX pathways, to some extent, was required for its effects on the phosphorylation of Akt, S6K1, ribosomal protein S6, 4EBP1, and eIF4E. In addition, AA increased PI3K activity in a time-dependent manner in VSMC. LY294002, an inhibitor of PI3K, completely blocked AA-induced phosphorylation of Akt, S6K1, ribosomal protein S6, 4EBP1, and eIF4E, suggesting a role for PI3K in these effects. Consistent with its effects on translation initiation signaling events, AA induced global protein synthesis in VSMC and this response was dependent, to some extent, on its metabolism via the LOX/MOX and/or COX pathways, and mediated by the PI3K/Akt/mTOR pathway. Thus, the above observations provide the first biochemical evidence for the role of AA in the activation of translation initiation signaling in VSMC.
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Affiliation(s)
- Indira Neeli
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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Laniado-Schwartzman M, Dunn MW. Cytochrome P450-derived eicosanoids mediators of ocular surface inflammation. are. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 525:47-54. [PMID: 12751735 DOI: 10.1007/978-1-4419-9194-2_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
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Yellaturu CR, Rao GN. Cytosolic phospholipase A2 is an effector of Jak/STAT signaling and is involved in platelet-derived growth factor BB-induced growth in vascular smooth muscle cells. J Biol Chem 2003; 278:9986-92. [PMID: 12529382 DOI: 10.1074/jbc.m211276200] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Platelet-derived growth factor-BB (PDGF-BB) is a potent mitogen and chemoattractant for vascular smooth muscle cells (VSMC). To understand its mitogenic and chemotactic signaling events, we studied the role of cytosolic phospholipase A(2) (cPLA(2)) and the Jak/STAT pathway. PDGF-BB induced the expression and activity of cPLA(2) in a time-dependent manner in VSMC. Arachidonyl trifluoromethyl ketone, a potent and specific inhibitor of cPLA(2), significantly reduced PDGF-BB-induced arachidonic acid release and DNA synthesis. PDGF-BB stimulated tyrosine phosphorylation of Jak-2 in a time-dependent manner. In addition, PDGF-BB activated STAT-3 as determined by its tyrosine phosphorylation, DNA-binding activity, and reporter gene expression, and these responses were suppressed by AG490, a selective inhibitor of Jak-2. AG490 and a dominant-negative mutant of STAT-3 also attenuated PDGF-BB-induced expression of cPLA(2,) arachidonic acid release, and DNA synthesis in VSMC. Together, these results suggest that induction of expression of cPLA(2) and arachidonic acid release are involved in VSMC growth in response to PDGF-BB and that these events are mediated by Jak-2-dependent STAT-3 activation.
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Affiliation(s)
- Chandrahasa R Yellaturu
- Department of Physiology and the Center for Vascular Biology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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Zeng ZZ, Yellaturu CR, Neeli I, Rao GN. 5(S)-hydroxyeicosatetraenoic acid stimulates DNA synthesis in human microvascular endothelial cells via activation of Jak/STAT and phosphatidylinositol 3-kinase/Akt signaling, leading to induction of expression of basic fibroblast growth factor 2. J Biol Chem 2002; 277:41213-9. [PMID: 12193593 DOI: 10.1074/jbc.m204508200] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To understand the role of eicosanoids in angiogenesis, we have studied the effect of lipoxygenase metabolites of arachidonic acid on human microvascular endothelial cell (HMVEC) DNA synthesis. Among the various lipoxygenase metabolites of arachidonic acid tested, 5(S)-hydroxyeicosatetraenoic acid (5(S)-HETE) induced DNA synthesis in HMVEC. 5(S)-HETE also stimulated Jak-2, STAT-1, and STAT-3 tyrosine phosphorylation and STAT-3-DNA binding activity. Tyrphostin AG490, a specific inhibitor of Jak-2, significantly reduced tyrosine phosphorylation and DNA binding activity of STAT-3 and DNA synthesis induced by 5(S)-HETE. In addition, 5(S)-HETE stimulated phosphatidylinositol 3-kinase (PI3-kinase) activity and phosphorylation of its downstream targets Akt, p70S6K, and 4E-BP1 and their effector molecules ribosomal protein S6 and eIF4E. LY294002 and rapamycin, potent inhibitors of PI3-kinase and mTOR, respectively, also blocked the DNA synthesis induced by 5(S)-HETE. Interestingly, AG490 attenuated 5(S)-HETE-induced PI3-kinase activity and phosphorylation of Akt, p70S6K, ribosomal protein S6, 4E-BP1, and eIF4E. 5(S)-HETE induced the expression of basic fibroblast growth factor 2 (bFGF-2) in a Jak-2- and PI3-kinase-dependent manner. In addition, a neutralizing anti-bFGF-2 antibody completely blocked 5(S)-HETE-induced DNA synthesis in HMVEC. Together these results suggest that 5(S)-HETE stimulates HMVEC growth via Jak-2- and PI3-kinase-dependent induction of expression of bFGF-2. These findings also reveal a cross-talk between Jak-2 and PI3-kinase in response to 5(S)-HETE in HMVEC.
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Affiliation(s)
- Zhao-Zhu Zeng
- Department of Physiology and Center for Vascular Biology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, TN 38163, USA
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