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Xu J, Yang G, Li T, Liu L. Myoendothelial gap junctions mediate regulation of angiopoietin-2-induced vascular hyporeactivity after hypoxia through connexin 43-gated cAMP transfer. Am J Physiol Cell Physiol 2017. [PMID: 28637680 DOI: 10.1152/ajpcell.00369.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Angiopoietin-2 (Ang-2) contributes to vascular hyporeactivity after hemorrhagic shock and hypoxia through upregulation of inducible nitric oxide synthase (iNOS) in a vascular endothelial cell (VEC)-specific and Ang-2/Tie2 receptor-dependent manner. While iNOS is primarily expressed in vascular smooth muscle cells (VSMCs), the mechanisms of signal transfer from VECs to VSMCs are unknown. A double-sided coculture model with VECs and VSMCs from Sprague-Dawley rats was used to investigate the role of myoendothelial gap junctions (MEGJs), the connexin (Cx) isoforms involved, and other relevant mechanisms. After hypoxia, VSMCs treated with exogenous Ang-2 showed increased iNOS expression and hyporeactivity, as well as MEGJ formation and communication. These Ang-2 effects were suppressed by the MEGJ inhibitor 18α-glycyrrhetic acid (18-GA), Tie2 siRNA, or Cx43 siRNA. Reagents antagonizing cAMP or protein kinase A (PKA) in VECs inhibited Cx43 expression in MEGJs, decreasing MEGJ formation and associated communication, after hypoxia following Ang-2 treatment. The increased cAMP levels in VSMCs and transfer of Alexa Fluor 488-labeled cAMP from VECs to VSMCs, after hypoxia following Ang-2 treatment, was antagonized by Cx43 siRNA. A cAMP antagonist added to VECs or VSMCs inhibited both increased iNOS expression and hyporeactivity in VSMCs subjected to hypoxia following Ang-2 treatment. Based on these findings, we propose that Cx43 was the Cx isoform involved in MEGJ-mediated VEC-dependent regulation of Ang-2, which induces iNOS protein expression and vascular hyporeactivity after hypoxia. Cx43 was upregulated by cAMP and PKA, permitting cAMP transfer between cells.
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Affiliation(s)
- Jing Xu
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
| | - Guangming Yang
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
| | - Tao Li
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
| | - Liangming Liu
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
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2
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Mao L, Zhou Q, Zhou S, Wilbur RR, Li X. Roles of apolipoprotein E (ApoE) and inducible nitric oxide synthase (iNOS) in inflammation and apoptosis in preeclampsia pathogenesis and progression. PLoS One 2013; 8:e58168. [PMID: 23472151 PMCID: PMC3589365 DOI: 10.1371/journal.pone.0058168] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Accepted: 02/03/2013] [Indexed: 02/05/2023] Open
Abstract
Objectives To investigate potential roles of inducible nitric oxide synthase (iNOS) and apolipoprotein (apoE) in inflammation and apoptosis promoting pathological changes in preeclampsia in pregnant mice with apoE and/or iNOS knock out. Methods B6.129 mice were crossed to produce WT, apoE−/−, apoE+/−, iNOS−/−, iNOS+/− and apoE−/−iNOS−/− groups. Variants were confirmed by PCR. Serum lipid parameters (triglycerides, TG; total cholesterol, TC; high density lipoprotein, HDL; and low density lipoprotein, LDL), NO levels and placental electronic microscopic ultrastructures were evaluated, and blood pressure (BP), 24-hour urine protein and pregnancy outcomes were recorded for pregnant F1 generation mice. Placental expressions of inflammatory (tumor necrosis factor-α, TNF-α; interleukin-6, IL-6; nuclear factor-κB, NF-κb) and apoptotic markers (Bcl-2 associated X protein, Bax, B-cell lymphoma/leukemia-2, Bcl-2, and Caspase-3) were evaluated via Western blot. Results Serum lipids, BP and 24-hour urine protein levels were shown to be significantly higher and parturition and placenta weights were lower in apoE−/− and apoE−/−iNOS−/− groups (p<0.05). NO levels were lower in the apoE−/−iNOS−/− group. In addition, inflammatory/apoptosis parameters, including TNF-α, IL-6, NF-κb, Bax, Bcl-2 and Caspase-3 in the apoE−/−iNOS−/− group (p<0.01), as well as in the apoE−/− group (p<0.05), and NF-κB, Bax in iNOS−/− group (p<0.05) were higher compared with WT group. However, most of the inflammatory/apoptosis parameters in the iNOS+/− and the apoE+/− groups (p>0.05) showed no differences. In addition, placenta vascular endothelial and trophoblast cell morphological changes were demonstrated in both the apoE−/−iNOS−/− and apoE−/− groups. Conclusion Elevated lipid metabolism and inflammatory/apoptosis parameters suggest a potentially significant role of apoE in preeclampsia pathology, as well as a relationship between iNOS and preeclampsia progression.
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Affiliation(s)
- Luyi Mao
- Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Qiongjie Zhou
- Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Shufeng Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida, United States of America
- * E-mail: (SZ); (XL)
| | - Rhonda R. Wilbur
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida, United States of America
| | - Xiaotian Li
- Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
- Institute of Biomedical Sciences, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, China
- * E-mail: (SZ); (XL)
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3
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Yang J, Zeng Y, Zhang C, Chen YX, Yang Z, Li Y, Leng X, Kong D, Wei XQ, Sun HF, Song CX. The prevention of restenosis in vivo with a VEGF gene and paclitaxel co-eluting stent. Biomaterials 2012. [PMID: 23199742 DOI: 10.1016/j.biomaterials.2012.11.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Long-term clinical studies of drug-eluting stents (DES) have reported high incidence of late thrombosis. Given the growing concern over the clinical application of this technology, we have developed a stent coated with bi-layered PLGA nanoparticles (BL-PLGA NPs) containing VEGF plasmid in the outer layer and paclitaxel (PTX) in the inner core (VEGF/PTX NPs). We hypothesized that early release of VEGF gene would promote re-endothelialization, while slow release of PTX would suppress smooth muscle cell proliferation. Using Fc plasmid as a reporter gene, we observed that Fc/PTX NPs successfully expressed Fc protein, but did not show cytotoxicity or anti-proliferative effect during the first 7 days in cell culture. In contrast, PTX NPs showed strong anti-proliferative effect staring from day 1 in culture, suggesting sequential release of gene and PTX from the BL-PLGA NPs. In vivo effects of the treated stent were assessed in mini-swines. Implantation of GFP/PTX NP-coated stents revealed efficient local GFP gene transfection at day 7. VEGF/PTX NP-coated stents showed complete re-endothelialization and significantly suppressed in-stent restenosis after 1 month compared to commercial DES. In conclusion, the VEGF/PTX NP-coated stents promote early endothelium healing while inhibit smooth muscle cell proliferation through sequential release of the VEGF gene and paclitaxel.
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Affiliation(s)
- Jing Yang
- Tianjin Key Laboratory of Biomaterial Research, Institute of Biomedical Engineering, Chinese Academy of Medical Science, Tianjin 300192, PR China
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4
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Perrotta I, Brunelli E, Sciangula A, Zuccalà V, Donato G, Tripepi S, Martinelli GL, Cassese M. Inducible and endothelial nitric oxide synthase expression in human atherogenesis: an immunohistochemical and ultrastructural study. Cardiovasc Pathol 2009; 18:361-8. [DOI: 10.1016/j.carpath.2008.08.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 06/25/2008] [Accepted: 08/19/2008] [Indexed: 10/21/2022] Open
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5
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Ginnan R, Guikema BJ, Halligan KE, Singer HA, Jourd’heuil D. Regulation of smooth muscle by inducible nitric oxide synthase and NADPH oxidase in vascular proliferative diseases. Free Radic Biol Med 2008; 44:1232-45. [PMID: 18211830 PMCID: PMC2390910 DOI: 10.1016/j.freeradbiomed.2007.12.025] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Revised: 12/11/2007] [Accepted: 12/11/2007] [Indexed: 10/22/2022]
Abstract
Inflammation plays a critical role in promoting smooth muscle migration and proliferation during vascular diseases such as postangioplasty restenosis and atherosclerosis. Another common feature of many vascular diseases is the contribution of reactive oxygen (ROS) and reactive nitrogen (RNS) species to vascular injury. Primary sources of ROS and RNS in smooth muscle are several isoforms of NADPH oxidase (Nox) and the cytokine-regulated inducible nitric oxide (NO) synthase (iNOS). One important example of the interaction between NO and ROS is the reaction of NO with superoxide to yield peroxynitrite, which may contribute to the pathogenesis of hypertension. In this review, we discuss the literature that supports an alternate possibility: Nox-derived ROS modulate NO bioavailability by altering the expression of iNOS. We highlight data showing coexpression of iNOS and Nox in vascular smooth muscle demonstrating the functional consequences of iNOS and Nox during vascular injury. We describe the relevant literature demonstrating that the mitogen-activated protein kinases are important modulators of proinflammatory cytokine-dependent expression of iNOS. A central hypothesis discussed is that ROS-dependent regulation of the serine/threonine kinase protein kinase Cdelta is essential to understanding how Nox may regulate signaling pathways leading to iNOS expression. Overall, the integration of nonphagocytic NADPH oxidase with cytokine signaling in general and in vascular smooth muscle in particular is poorly understood and merits further investigation.
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Affiliation(s)
| | | | | | | | - David Jourd’heuil
- To whom correspondence should be addressed: Albany Medical College, Center for Cardiovascular Sciences, 47 New Scotland Avenue (MC8), Albany, NY 12208; Tel: (518) 262 8104; Fax: (518) 262 8101; E-mail:
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6
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Leung BM, Sefton MV. A modular tissue engineering construct containing smooth muscle cells and endothelial cells. Ann Biomed Eng 2007; 35:2039-49. [PMID: 17882548 DOI: 10.1007/s10439-007-9380-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2007] [Accepted: 09/05/2007] [Indexed: 11/28/2022]
Abstract
Human umbilical vein endothelial cells (HUVEC) were seeded on sub-mm sized collagen cylinders containing embedded umbilical vein smooth muscle cells (UVSMC). These cylindrical "modules" are intended to be used as a vascularized construct, in which HUVEC lined channels are created by the random packing of the modules in situ or within a larger container. Embedding UVSMC cultured in medium containing 10% FBS had an adverse effect on subsequently seeded HUVEC junction morphology; HUVEC/UVSMC co-culturing was done in HUVEC medium (2% FBS with the addition of 0.03 mg/mL endothelial cell growth supplement) as compared to HUVEC seeded on collagen-only modules. In contrast, embedding UVSMC cultured in serum-free medium prior to embedding improved EC junction morphology. Such serum-free culturing, also prevented the UVSMC induced contraction of the collagen modules. On the other hand, embedding serum-free cultured UVSMC promoted HUVEC proliferation and NO secretion compared to those modules embedded with 10% serum cultured UVSMC. These results suggest, not surprisingly, that embedded UVSMC phenotype plays an important role in the seeded HUVEC phenotype, and that the response can be modulated by the UVSMC culture medium serum concentration. These studies were undertaken with a view to using the UVSMC to modulate the thrombogenicity of the HUVEC. Exploration of this outcome awaits further studies directed to understanding the mechanism of the cellular interactions.
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Affiliation(s)
- Brendan M Leung
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College St, M5S 3G9, Toronto, ON, Canada
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7
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Jones RJ, Jourd'heuil D, Salerno JC, Smith SME, Singer HA. iNOS regulation by calcium/calmodulin-dependent protein kinase II in vascular smooth muscle. Am J Physiol Heart Circ Physiol 2007; 292:H2634-42. [PMID: 17293490 DOI: 10.1152/ajpheart.01247.2006] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide synthase (NOS) expression is regulated transcriptionally in response to cytokine induction and posttranslationally by palmitoylation and trafficking into perinuclear aggresome-like structures. We investigated the effects of multifunctional calcium/calmodulin-dependent protein kinase II protein kinase (CaMKII) on inducible NOS (iNOS) trafficking in cultured rat aortic vascular smooth muscle cells (VSMCs). Immunofluorescence and confocal microscopy demonstrated colocalization of iNOS and CaMKIIdelta(2) with a perinuclear distribution and concentration in aggresome-like structures identified by colocalization with gamma-tubulin. Furthermore, CaMKIIdelta(2) coimmunoprecipitated with iNOS in a CaMKII activity-dependent manner. Addition of Ca(2+)-mobilizing stimuli expected to activate CaMKII; a purinergic agonist (UTP) or calcium ionophore (ionomycin) caused a general redistribution of iNOS from cytosolic to membrane and nuclear fractions. Similarly, adenoviral expression of a constitutively active CaMKIIdelta(2) mutant altered iNOS localization, shifting iNOS from the cytosolic fraction. Suppression of CaMKIIdelta(2) using an adenovirus expressing a short hairpin, small interfering RNA increased nuclear iNOS localization in resting cells but inhibited ionomycin-induced translocation of iNOS to the nucleus. Following addition of these chronic and acute CaMKII modulators, there were fewer aggresome-like structures containing iNOS. All of the treatments that chronically affected CaMKII activity or expression significantly inhibited iNOS-specific activity following cytokine induction. The results suggest that CaMKIIdelta(2) may be an important regulator of iNOS trafficking and activity in VSMCs.
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MESH Headings
- Animals
- Aorta, Thoracic/cytology
- Aorta, Thoracic/metabolism
- Benzylamines/pharmacology
- Calcium/metabolism
- Calcium-Calmodulin-Dependent Protein Kinase Type 2
- Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors
- Calcium-Calmodulin-Dependent Protein Kinases/genetics
- Calcium-Calmodulin-Dependent Protein Kinases/metabolism
- Cell Membrane/enzymology
- Cell Nucleus/enzymology
- Cells, Cultured
- Cytokines/metabolism
- Cytoplasm/enzymology
- Enzyme Induction
- Interferon-gamma/metabolism
- Interleukin-1beta/metabolism
- Ionomycin/pharmacology
- Ionophores/pharmacology
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/enzymology
- Nitric Oxide Synthase Type II/biosynthesis
- Protein Kinase Inhibitors/pharmacology
- Protein Transport
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Rats
- Rats, Sprague-Dawley
- Signal Transduction/drug effects
- Sulfonamides/pharmacology
- Tumor Necrosis Factor-alpha/metabolism
- Uridine Triphosphate/metabolism
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Affiliation(s)
- Rachel J Jones
- Center for Cardiovascular Sciences, Albany Medical College, 43 New Scotland Ave., Albany, NY 12208, USA
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8
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Yang J, Ji R, Cheng Y, Sun JZ, Jennings LK, Zhang C. L-arginine chlorination results in the formation of a nonselective nitric-oxide synthase inhibitor. J Pharmacol Exp Ther 2006; 318:1044-9. [PMID: 16717106 DOI: 10.1124/jpet.106.104422] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Reduced nitric oxide (NO) bioavailability and impaired vascular function are the key pathological characteristics of inflammatory diseases such as atherosclerosis. We have recently found that leukocyte-derived hypochlorous acid is able to react with the nitric-oxide synthase (NOS) substrate L-arginine to produce chlorinated L-arginine (cl-L-Arg). Interestingly, cl-L-Arg potently inhibits the formation of NO metabolites in cultured endothelial cells. It is unknown whether cl-L-Arg has a direct inhibitory effect on endothelial NOS (eNOS). In addition, the effect of cl-L-Arg on the other NOS isoforms, neuronal NOS (nNOS) and inducible NOS (iNOS), is also unknown. Therefore, we designed the current study to test the effects of cl-L-Arg on eNOS, nNOS, and iNOS. Using recombinant NOS, we found that cl-L-Arg had a direct inhibitory effect on the activity of NOS. The effect of cl-L-Arg on NOS activity is nonselective, as all three NOS isoforms were inhibited with a similar IC(50). We further determined the effect of cl-L-Arg on the three NOS isoforms at the tissue level. The results demonstrated that cl-L-Arg potently inhibited all three NOS isoform-mediated vessel reactivities, as well as the NOS signaling molecule cGMP. Cl-L-Arg might serve as a novel endogenous NOS inhibitor and an important mediator for vascular dysfunction under inflammatory conditions such as atherosclerosis. Blocking cl-L-Arg formation may be a new therapeutic approach to cardiovascular diseases.
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Affiliation(s)
- Jian Yang
- Vascular Biology Center, Department of Surgery, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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9
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Fischer JH, Funcke C, Yotsumoto G, Jeschkeit-Schubbert S, Kuhn-Régnier F. Maintenance of physiological coronary endothelial function after 3.3 h of hypothermic oxygen persufflation preservation and orthotopic transplantation of non-heart-beating donor hearts. Eur J Cardiothorac Surg 2004; 25:98-104. [PMID: 14690739 DOI: 10.1016/s1010-7940(03)00673-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE The use of non-heart-beating donors (NHBD) might increase the number of grafts available for transplantation. Experiments on heart transplantation from NHBDs demonstrated the necessity for oxygenation during preservation to allow sufficient myocardial recovery. It has been shown that, after 16 min normothermic ischemia followed by 3.3-h hypothermic preservation, excellent myocardial and cardiovascular recovery is attained, if coronary oxygen persufflation (COP) is included in the preservation protocol. Here tests are presented on the recovery of coronary endothelium derived relaxation (EDR) of NHBD hearts after preservation including COP. METHODS After 16 min normothermic ischemia, pig hearts were stored for 3.3 h at 0-1 degrees C in modified HTK plus COP (mBHTK+COP, n=6) or in two control groups without COP: (1) with mBHTK (n=6); and (2) with HTK (n=4). Following orthotopic transplantation and 3 h of reperfusion with full blood, coronary EDR was tested in vitro using Substance P (SP) under indomethacin for prostaglandin blockage. Additional tests were performed adding L-NIL to block the NO-production by iNOS or L-NNA to block total NO production. RESULTS The EDR in percent of precontraction was 78 +/- 7% after mBHTK+COP and 77 +/- 20% (mBHTK) or 72 +/- 7% (HTK) in the controls without significant differences between the groups. Physiologic values of normal coronaries were 75 +/- 9%. L-NIL for blockage of NO-production by iNOS resulted in unchanged relaxations. After blockage of total NO production by L-NNA, the SP-induced dilation was significantly reduced to 58 +/- 8% (mBHTK+COP) and to 48 +/- 8% (mBHTK) or 55 +/- 13% (HTK) in the controls. CONCLUSIONS Even after 16 min of warm ischemia followed by 3.3 h of preservation with gaseous oxygen persufflation, orthotopic transplantation, and reperfusion the endothelium derived coronary dilatation was unchanged from physiologic values and similar to the controls without COP. Blockage of NO production by L-NNA resulted in equal values of EDR with or without COP, while blockage of NO production by iNOS did not influence the EDR reaction. Thus COP preservation, which has been shown to allow excellent recovery of preserved NHBD hearts, caused no damage to the coronary EDR mechanisms.
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Affiliation(s)
- Jürgen H Fischer
- Institute of Experimental Medicine, University of Cologne, Robert-Koch-Str 10, 50931 Cologne, Germany.
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10
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Gobeil F, Bernier SG, Vazquez-Tello A, Brault S, Beauchamp MH, Quiniou C, Marrache AM, Checchin D, Sennlaub F, Hou X, Nader M, Bkaily G, Ribeiro-da-Silva A, Goetzl EJ, Chemtob S. Modulation of pro-inflammatory gene expression by nuclear lysophosphatidic acid receptor type-1. J Biol Chem 2003; 278:38875-83. [PMID: 12847111 DOI: 10.1074/jbc.m212481200] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a bioactive molecule involved in inflammation, immunity, wound healing, and neoplasia. Its pleiotropic actions arise presumably by interaction with their cell surface G protein-coupled receptors. Herein, the presence of the specific nuclear lysophosphatidic acid receptor-1 (LPA1R) was revealed in unstimulated porcine cerebral microvascular endothelial cells (pCMVECs), LPA1R stably transfected HTC4 rat hepatoma cells, and rat liver tissue using complementary approaches, including radioligand binding experiments, electron- and cryomicroscopy, cell fractionation, and immunoblotting with three distinct antibodies. Coimmunoprecipitation studies in enriched plasmalemmal fractions of unstimulated pCMVEC showed that LPA1Rs are dually sequestrated in caveolin-1 and clathrin subcompartments, whereas in nuclear fractions LPA1R appeared primarily in caveolae. Immunofluorescent assays using a cell-free isolated nuclear system confirmed LPA1R and caveolin-1 co-localization. In pCMVEC, LPA-stimulated increases in cyclooxygenase-2 and inducible nitric-oxide synthase RNA and protein expression were insensitive to caveolea-disrupting agents but sensitive to LPA-generating phospholipase A2 enzyme and tyrosine kinase inhibitors. Moreover, LPA-induced increases in Ca2+ transients and/or iNOS expression in highly purified rat liver nuclei were prevented by pertussis toxin, phosphoinositide 3-kinase/Akt inhibitor wortmannin and Ca2+ chelator and channel blockers EGTA and SK&F96365, respectively. This study describes for the first time the nucleus as a potential organelle for LPA intracrine signaling in the regulation of pro-inflammatory gene expression.
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MESH Headings
- Androstadienes/pharmacology
- Animals
- Blotting, Western
- Calcium/metabolism
- Caveolin 1
- Caveolins/metabolism
- Cell Nucleus/metabolism
- Cell-Free System/metabolism
- Cells, Cultured
- Chelating Agents/pharmacology
- Clathrin/metabolism
- Egtazic Acid/pharmacology
- Endothelium, Vascular/cytology
- Enzyme Inhibitors/pharmacology
- Gene Expression Regulation
- Immunoblotting
- Liver/metabolism
- Microcirculation
- Microscopy, Electron
- Microscopy, Fluorescence
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type II
- Pertussis Toxin/pharmacology
- Phosphoinositide-3 Kinase Inhibitors
- Phospholipases A/metabolism
- Phospholipases A2
- Precipitin Tests
- Protein Binding
- Protein-Tyrosine Kinases/metabolism
- Rats
- Receptors, Cell Surface/metabolism
- Receptors, Cell Surface/physiology
- Receptors, G-Protein-Coupled
- Receptors, Lysophosphatidic Acid
- Subcellular Fractions/metabolism
- Swine
- Time Factors
- Transfection
- Tumor Cells, Cultured
- Wortmannin
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Affiliation(s)
- Fernand Gobeil
- Departments of Pediatrics, Ophthalmology and Pharmacology, Research Center of Hôpital Sainte-Justine, Montréal, Québec H3T 1C5, Canada.
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11
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Smeets MB, Pasterkamp G, Lim SK, Velema E, van Middelaar B, de Kleijn DPV. Nitric oxide synthesis is involved in arterial haptoglobin expression after sustained flow changes. FEBS Lett 2002; 529:221-4. [PMID: 12372604 DOI: 10.1016/s0014-5793(02)03343-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The acute phase protein haptoglobin is highly expressed in arteries after sustained flow changes and involved in cell migration and arterial restructuring. In the liver, haptoglobin expression is mainly regulated by interleukin-6 (IL-6). In the artery, shear stress and NO influence IL-6 expression. In the present study, we demonstrate that NO synthesis is involved in the regulation of arterial haptoglobin expression after sustained flow changes. Decreased haptoglobin expression after NO inhibition coincided with decreased IL-6 levels. However, IL-6 knockout mice had normal arterial haptoglobin expression levels after sustained flow changes suggesting that other mediators may provide compensatory mechanisms for the regulation of arterial haptoglobin expression.
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Affiliation(s)
- Mirjam B Smeets
- Experimental Cardiology Laboratory, University Medical Center, Heidelberglaan 100 (room G02.523), 3584 CX Utrecht, The Netherlands
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12
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Buchwalow IB, Podzuweit T, Bocker W, Samoilova VE, Thomas S, Wellner M, Baba HA, Robenek H, Schnekenburger J, Lerch MM. Vascular smooth muscle and nitric oxide synthase. FASEB J 2002; 16:500-8. [PMID: 11919152 DOI: 10.1096/fj.01-0842com] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The concept of endothelium-derived relaxing factor (EDRF) put forward in 1980 by Furchgott and Zawadzki implies that nitric oxide (NO) produced by NO synthase (NOS) in the endothelium diffuses to the underlying vascular smooth muscle, where it modulates vascular tone as well as vascular smooth muscle cell (VSMC) proliferation by increasing cGMP formation with subsequent activation of cGMP-dependent protein kinase. According to this concept, VSMC do not express NOS by themselves. This attractive, simple scheme is now under considerable debate. To address this issue, we designed this study with the use of a novel supersensitive immunocytochemical technique of signal amplification with tyramide and electron microscopic immunogold labeling complemented with Western blotting, as in our recent studies demonstrating NOS in the myocardial and skeletal muscles. We provide the first evidence that, in contrast to the currently accepted view, VSMC in various blood vessels express all three NOS isoforms depending on the blood vessel type. These findings suggest an alternative mechanism by which local NOS expression may modulate vascular functions in an endothelium-independent manner.
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Affiliation(s)
- Igor B Buchwalow
- Department of Medicine B, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany.
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13
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Tolbert T, Thompson JA, Bouchard P, Oparil S. Estrogen-induced vasoprotection is independent of inducible nitric oxide synthase expression: evidence from the mouse carotid artery ligation model. Circulation 2001; 104:2740-5. [PMID: 11723029 DOI: 10.1161/hc4701.099581] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Estrogen is vasoprotective in animal models of vascular injury, yet the mechanisms involved are incompletely understood. The role of inducible nitric oxide synthase (iNOS) in vascular repair is controversial, but many lines of evidence indicate that it plays a role in neointima formation after arterial injury and that 17beta-estradiol (E(2)) modulates iNOS expression. This study tested the hypothesis that E(2) reduces neointima formation after vascular injury via a mechanism that is dependent on modulation of iNOS expression. METHODS AND RESULTS Male and female wild-type (iNOS(+/+)) mice and mice with homozygous deletion of the iNOS gene (iNOS(-/-)) were studied intact (INT) or after ovariectomy (OVX) and implantation of E(2) or vehicle (V) pellets. Mice were randomized to 8 groups based on sex, iNOS status, OVX, and treatment with E(2) or V. Twenty-eight days after carotid artery ligation, mice were euthanized, and occluded vessels were evaluated for neointima formation by morphometric analysis. There was a marked sexual dimorphism in neointima formation in both the iNOS(+/+) mice and the iNOS(-/-) mice. iNOS(+/+) INT females had a >90% reduction in neointima formation compared with iNOS(+/+) males, and iNOS(-/-) INT females had a 65% reduction in neointima formation compared with iNOS(-/-) males. The sexually dimorphic response was attenuated by OVX and restored by E(2) replacement in both iNOS(+/+) and iNOS(-/-) mice. CONCLUSIONS These results demonstrate that the vasoprotective effects of E(2) after ligation vascular injury are, at least in part, independent of iNOS expression.
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Affiliation(s)
- T Tolbert
- Departments of Medicine, Division of Cardiovascular Diseases, Division of Transplantation, University of Alabama at Birmingham, USA.
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Lee JK, Borhani M, Ennis TL, Upchurch GR, Thompson RW. Experimental abdominal aortic aneurysms in mice lacking expression of inducible nitric oxide synthase. Arterioscler Thromb Vasc Biol 2001; 21:1393-401. [PMID: 11557662 DOI: 10.1161/hq0901.095750] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To determine if nitric oxide synthase (NOS) contributes to the pathophysiology of abdominal aortic aneurysms (AAAs), C57BL/6J mice underwent transient aortic injury to induce a chronic inflammatory response. Wild-type mice developed a significant increase in aortic diameter within 14 days of elastase perfusion (115+/-16%, 40% incidence of AAAs), along with intense and widespread staining for nitrotyrosine, mononuclear inflammation, and delayed destruction of the elastic lamellae. Expression of both endothelial and neuronal forms of NOS was substantially decreased within AAAs, whereas inducible NOS (iNOS) mRNA was increased 360%, and the enzyme was localized to infiltrating inflammatory cells. By using mice with targeted deletion of iNOS to evaluate the functional importance of this enzyme, male iNOS(-/-) mice developed the same extent of aneurysmal dilatation as congenic controls (121+/-22%, 40% incidence of AAAs) and exhibited similar structural features except for diminished nitrotyrosine staining. Aneurysmal dilatation was actually enhanced in female iNOS(-/-) mice (141+/-16%, 80% incidence of AAAs; P<0.05), but this effect was reversed by previous oophorectomy. Although extensive protein nitration and increased expression of iNOS accompany the development of elastase-induced experimental AAAs, iNOS is not required in this process and its absence may be deleterious.
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Affiliation(s)
- J K Lee
- Department of Surgery, Section of Vascular Surgery, Washington University School of Medicine, Saint Louis, MO, USA
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Ihrig M, Dangler CA, Fox JG. Mice lacking inducible nitric oxide synthase develop spontaneous hypercholesterolaemia and aortic atheromas. Atherosclerosis 2001; 156:103-7. [PMID: 11369002 DOI: 10.1016/s0021-9150(00)00636-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide (NO) has been implicated in various aspects of the atherogenic process and has been shown to possess both protective and cytotoxic properties. Recently, increased expression of inducible nitric oxide synthase (iNOS) has been detected in atherosclerotic lesions, although there is no consensus as to its pathogenetic significance [1,2]. In this longitudinal study we show that iNOS plays an important protective role in the atherogenic process. Indirect systolic blood pressure was measured by photoplethysmography in unanesthetized mice fed either a basal or high salt diet, and found to be significantly higher in iNOS-deficient mice than in wild type controls at three months of age (P=0.038 (basal diet) and P=0.0005 (high salt diet)). In addition, relative to controls, the iNOS-deficient mice had significantly elevated serum cholesterol levels at 3, 9 and 12 months of age (P=0.0017, 0.0001 and 0.0002 for the respective ages) as well as a significantly higher incidence of atherosclerotic plaques. These findings suggest that iNOS targeted mutant mice, historically used as an animal model to investigate the role of nitric oxide in the inflammatory response [3,4], may also serve as a model for the study of cholesterol homeostasis and atherogenesis.
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Affiliation(s)
- M Ihrig
- Division of Comparative Medicine, Massachusetts Institute of Technology, Building 16-825, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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O'Donnell VB, Freeman BA. Interactions between nitric oxide and lipid oxidation pathways: implications for vascular disease. Circ Res 2001; 88:12-21. [PMID: 11139468 DOI: 10.1161/01.res.88.1.12] [Citation(s) in RCA: 172] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Nitric oxide ((.)NO) signaling pathways and lipid oxidation reactions are of central importance in both the maintenance of vascular homeostasis and the progression of vascular disease. Because both of these pathways involve free radical species that can also react together at extremely fast rates, convergent interactions between these pathways are expected. Biochemical and cell biology studies have defined multiple interactions of (.)NO with oxidizing lipids that could lead to either vascular protection or potentiation of inflammatory vascular injury. For example, low levels of (.)NO generated by endothelial nitric oxide synthase can terminate propagating lipid radicals and inhibit lipoxygenases, reactions that would be protective. Alternatively, if generated at elevated levels, for example, after inducible nitric oxide synthase expression in inflammation, (.)NO can be converted to prooxidant species, such as peroxynitrite (ONOO(-)) and nitrogen dioxide ((.)NO(2)), that can potentiate inflammatory injury to vascular cells. Finally, both enzymatic and nonenzymatic lipid oxidation reactions can influence (.)NO bioactivity by directly scavenging (.)NO or altering the induction and catalytic activity of nitric oxide synthase enzymes. In this review, we summarize the biochemical interactions between (.)NO and lipid oxidation reactions and discuss the recognized and potential roles of these reactions in the vasculature.
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Affiliation(s)
- V B O'Donnell
- Wales Heart Research Institute, University of Wales College of Medicine, Heath Park, Cardiff, Wales, UK.
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Channon KM, Qian H, George SE. Nitric oxide synthase in atherosclerosis and vascular injury: insights from experimental gene therapy. Arterioscler Thromb Vasc Biol 2000; 20:1873-81. [PMID: 10938006 DOI: 10.1161/01.atv.20.8.1873] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Gene therapy aims to intervene in a disease process by transfer and expression of specific genes in a target tissue or organ. Cardiovascular gene therapy in humans remains in its infancy, but in the last decade, experimental gene transfer has emerged as a powerful biological tool to investigate the function of specific genes in vascular disease pathobiology. Nitric oxide synthases, the enzymes that produce nitric oxide, have received considerable attention as potential candidates for vascular gene therapy because nitric oxide has pleiotropic antiatherogenic actions in the vessel wall, and abnormalities in nitric oxide biology are apparent very early in the atherogenic process. In this article, we review the use of nitric oxide synthases in experimental vascular gene therapy and assess the utility of these approaches for investigating the role of nitric oxide in atherosclerosis and their potential for human gene therapy.
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Affiliation(s)
- K M Channon
- Department of Cardiovascular Medicine (K.M.C.), University of Oxford, John Radcliffe Hospital, Oxford, England.
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Miller FJ. AIF-1 in the activated smooth muscle cell : spectator or participant? Arterioscler Thromb Vasc Biol 2000; 20:1701-3. [PMID: 10894805 DOI: 10.1161/01.atv.20.7.1701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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