1
|
Munshi A, Das S. Genetic Understanding of Stroke Treatment: Potential Role for Phosphodiesterase Inhibitors. ADVANCES IN NEUROBIOLOGY 2017; 17:445-461. [PMID: 28956342 DOI: 10.1007/978-3-319-58811-7_16] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Phosphodiesterase (PDE) gene family is a large family having at least 21 genes and multiple versions (isoforms) of the phosphodiesterase enzymes. These enzymes catalyze the inactivation of intracellular mediators of signal transduction such as cAMP and cGMP and therefore, play a pivotal role in various cellular functions. PDE inhibitors (PDEI) are drugs that block one or more of the five subtypes of the PDE family and thereby prevent inactivation of the intracellular cAMP and cGMP by the respective PDE-subtypes. The first clinical use of PDEI was reported almost three decades ago. Studies later found the ability of these compounds to increase the levels of ubiquitous secondary messenger molecules that can cause changes in vascular tone, cardiac function and other cellular events and thus these findings paved the way for their use in various medical emergencies. PDEs are found to be distributed in many tissues including brain. Therefore, new therapeutic agents in the form of PDEI are being explored in neurodegenerative diseases including stroke. Although studies have revealed their use in cerebral infarction prevention, their full-fledged application in times of neurological emergency or stroke in specific has been very limited so far. Nevertheless, recent investigations suggest PDE4 and PDE5 inhibitors to play a vital role in mitigating stroke symptoms by modulating signaling mechanisms in PDE pathway. Further, extensive research in terms of their pharmacological properties like dosing, drug specific activities, use of simultaneous medications, ancillary properties of these compounds and studies on adverse drug reactions needs to be carried out to set them as standard drugs of use in stroke.
Collapse
Affiliation(s)
- Anjana Munshi
- Centre for Human Genetics and Molecular Medicine, School of Health Sciences, Central University of Punjab, Bathinda, Punjab, India.
| | - Satrupa Das
- Institute of Genetics and Hospital for Genetic Diseases, Osmania University, Begumpet, Hyderabad, 500016, India
- Dr. NTR University of Health Sciences, Vijayawada, Andhra Pradesh, India
| |
Collapse
|
2
|
Nassi A, Malorgio F, Tedesco S, Cignarella A, Gaion RM. Upregulation of inducible NO synthase by exogenous adenosine in vascular smooth muscle cells activated by inflammatory stimuli in experimental diabetes. Cardiovasc Diabetol 2016; 15:32. [PMID: 26879172 PMCID: PMC4754884 DOI: 10.1186/s12933-016-0349-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 02/02/2016] [Indexed: 01/19/2023] Open
Abstract
Background Adenosine has been shown to induce nitric oxide (NO) production via inducible NO synthase (iNOS) activation in vascular smooth muscle cells (VSMCs). Although this is interpreted as a beneficial vasodilating pathway in vaso-occlusive disorders, iNOS is also involved in diabetic vascular dysfunction. Because the turnover of and the potential to modulate iNOS by adenosine in experimental diabetes have not been explored, we hypothesized that both the adenosine system and control of iNOS function are impaired in VSMCs from streptozotocin-diabetic rats. Methods Male Sprague–Dawley rats were injected with streptozotocin once to induce diabetes. Aortic VSMCs from diabetic and nondiabetic rats were isolated, cultured and exposed to lipopolysaccharide (LPS) plus a cytokine mix for 24 h in the presence or absence of (1) exogenous adenosine and related compounds, and/or (2) pharmacological agents affecting adenosine turnover. iNOS functional expression was determined by immunoblotting and NO metabolite assays. Concentrations of adenosine, related compounds and metabolites thereof were assayed by HPLC. Vasomotor responses to adenosine were determined in endothelium-deprived aortic rings. Results Treatment with adenosine-degrading enzymes or receptor antagonists increased iNOS formation in activated VSMCs from nondiabetic and diabetic rats. Following treatment with the adenosine transport inhibitor NBTI, iNOS levels increased in nondiabetic but decreased in diabetic VSMCs. The amount of secreted NO metabolites was uncoupled from iNOS levels in diabetic VSMCs. Addition of high concentrations of adenosine and its precursors or analogues enhanced iNOS formation solely in diabetic VSMCs. Exogenous adenosine and AMP were completely removed from the culture medium and converted into metabolites. A tendency towards elevated inosine generation was observed in diabetic VSMCs, which were also less sensitive to CD73 inhibition, but inosine supplementation did not affect iNOS levels. Pharmacological inhibition of NOS abolished adenosine-induced vasorelaxation in aortic tissues from diabetic but not nondiabetic animals. Conclusions Endogenous adenosine prevented cytokine- and LPS-induced iNOS activation in VSMCs. By contrast, supplementation with adenosine and its precursors or analogues enhanced iNOS levels in diabetic VSMCs. This effect was associated with alterations in exogenous adenosine turnover. Thus, overactivation of the adenosine system may foster iNOS-mediated diabetic vascular dysfunction.
Collapse
Affiliation(s)
- Alberto Nassi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy. .,Transplant Immunology Unit, Padua University Hospital, Padova, Italy.
| | - Francesca Malorgio
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy.
| | - Serena Tedesco
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy.
| | | | - Rosa Maria Gaion
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy.
| |
Collapse
|
3
|
Marques SM, Castro PR, Campos PP, Viana CTR, Parreiras PM, Ferreira MAN, Andrade SP. Genetic strain differences in the development of peritoneal fibroproliferative processes in mice. Wound Repair Regen 2015; 22:381-9. [PMID: 24844337 DOI: 10.1111/wrr.12177] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 02/28/2014] [Indexed: 12/17/2022]
Abstract
Fibroproliferative processes are regulated by a wide variety of tissue components and genetic factors. However, whether there are genetic differences in peritoneal fibroproliferative tissue formation, with consequent differences in response to drug treatment, is unclear. We characterize the influence of the genetic background on peritoneal fibroproliferative tissue induced by sponge implants in DBA/1, Swiss, C57BL/6, and BALB/c mouse strains. In addition, responses to dipyridamole in the implants were evaluated. Angiogenesis, assessed by intra-implant hemoglobin content, was highest in Swiss mice, whereas levels of vascular endothelial growth factor were highest in C57BL/6 mice. The levels of pro-inflammatory cytokines and of inflammatory enzymes (myeloperoxidase- and N-acetyl-β-D-glucosaminidase) were also strain-related. The pro-fibrogenic markers transforming growth factor beta-1 and collagen were lowest in implants placed in DBA/1 mice, whereas those in C57BL/6 mice had the highest levels. Differential sensitivity to dipyridamole was also observed, with this compound being pro-angiogenic in implants placed in DBA/1 mice but antiangiogenic in implants placed in Swiss. An overall anti-inflammatory response was observed in the inbred strains. Antifibrogenic effects were observed only in implants placed in C57BL/6 mice. These important strain-related differences in the development of peritoneal fibrosis and in response to dipyridamole must be considered in the design and analysis of studies on fibrogenesis in mice.
Collapse
Affiliation(s)
- Suzane M Marques
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | | | | | | | | | | | | |
Collapse
|
4
|
Sampaio FP, Castro PR, Marques SM, Campos PP, Ferreira MAND, Andrade SP. Genetic background determines inflammatory angiogenesis response to dipyridamole in mice. Exp Biol Med (Maywood) 2012; 237:1084-92. [DOI: 10.1258/ebm.2012.012066] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Inflammation and angiogenesis, key components of fibrovascular tissue growth, exhibit considerable variability among species and strains. We investigated whether the response of inbred and outbred mice strains to dipyridamole (DP) on these processes would present similar variability. The effects of the drug on blood vessel formation, inflammatory cell recruitment, collagen deposition and cytokine production were determined on the fibroproliferative tissue induced by sponge implants in Swiss and Balb/c mice. Angiogenesis as assessed by hemoglobin (Hb) and vascular endothelial growth factor (VEGF) concentrations differed between the strains. Swiss implants had the highest Hb content but the lowest VEGF concentrations. Systemic DP treatment exerted an antiangiogenic effect on Balb/c implants but an proangiogenic effect on Swiss implants. The inflammatory enzyme activities myeloperoxidase (six-fold higher in Balb/c implants) and N-acetyl- β-d-glucosaminidase were reduced by the treatment in Balb/c implants only. Nitrite concentrations were also higher in Balb/c implants by 40% after DP treatment. Tumor necrosis factor-alpha levels were similar in the implants of both strains and were not reduced by DP. Transforming growth factor β-1 levels and collagen deposition also varied between the strains. The inbred strain had similar levels of the cytokine but implants of Swiss mice presented more collagen. DP treatment reduced collagen deposition in Balb/c implants only. Our data showing the influence of the genetic background on marked heterogeneity of inflammatory angiogenesis components and differential sensitivity to DP may provide some answers to clinical evidence for resistance to angiogenic therapy.
Collapse
Affiliation(s)
| | | | | | - Paula Peixoto Campos
- General Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Av. Antônio Carlos 6627-Campus Pampulha, Cx Post 468, CEP 31270-901, Belo Horizonte/MG, Brazil
| | - Mônica Alves Neves Diniz Ferreira
- General Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Av. Antônio Carlos 6627-Campus Pampulha, Cx Post 468, CEP 31270-901, Belo Horizonte/MG, Brazil
| | | |
Collapse
|
5
|
Gresele P, Momi S, Falcinelli E. Anti-platelet therapy: phosphodiesterase inhibitors. Br J Clin Pharmacol 2012; 72:634-46. [PMID: 21649691 DOI: 10.1111/j.1365-2125.2011.04034.x] [Citation(s) in RCA: 199] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Inhibition of platelet aggregation can be achieved either by the blockade of membrane receptors or by interaction with intracellular signalling pathways. Cyclic adenosine 3',5'-monophosphate (cAMP) and cyclic guanosine 3',5'-monophosphate (cGMP) are two critical intracellular second messengers provided with strong inhibitory activity on fundamental platelet functions. Phosphodiesterases (PDEs), by catalysing the hydrolysis of cAMP and cGMP, limit the intracellular levels of cyclic nucleotides, thus regulating platelet function. The inhibition of PDEs may therefore exert a strong platelet inhibitory effect. Platelets possess three PDE isoforms (PDE2, PDE3 and PDE5), with different selectivity for cAMP and cGMP. Several nonselective or isoenzyme-selective PDE inhibitors have been developed, and some of them have entered clinical use as antiplatelet agents. This review focuses on the effect of PDE2, PDE3 and PDE5 inhibitors on platelet function and on the evidence for an antithrombotic action of some of them, and in particular of dipyridamole and cilostazol.
Collapse
Affiliation(s)
- Paolo Gresele
- Department of Internal Medicine, Section of Internal and Cardiovascular Medicine, University of Perugia, Italy.
| | | | | |
Collapse
|
6
|
Prandota J. Recurrent headache as the main symptom of acquired cerebral toxoplasmosis in nonhuman immunodeficiency virus-infected subjects with no lymphadenopathy: the parasite may be responsible for the neurogenic inflammation postulated as a cause of different types of headaches. Am J Ther 2007; 14:63-105. [PMID: 17303977 DOI: 10.1097/01.mjt.0000208272.42379.aa] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Headache and/or migraine, a common problem in pediatrics and internal medicine, affect about 5% to 10% children and adolescents, and nearly 30% of middle-aged women. Headache is also one of the most common clinical manifestations of acquired Toxoplasma gondii infection of the central nervous system (CNS) in immunosuppressed subjects. We present 11 apparently nonhuman immunodeficiency virus-infected children aged 7 to 17 years (8 girls, 3 boys) and 1 adult woman with recurrent severe headaches in whom latent chronic CNS T. gondii infection not manifested by enlarged peripheral lymph nodes typical for toxoplasmosis, was found. In 7 patients, the mean serum IgG Toxoplasma antibodies concentration was 189 +/- 85 (SD) IU/mL (range 89 to 300 IU/mL), and in 5 other subjects, the indirect fluorescent antibody test titer ranged from 1:40 to 1:5120 IU/mL (n= <1:10 IU/mL). Some of the patients suffered also from atopic dermatitis (AD) and were exposed to cat and/or other pet allergens, associated with an increased IL-4 and decreased IFN-gamma production. These cytokine irregularities caused limited control of cerebral toxoplasmosis probably because IL-4 down-regulated both the production of IFN-gamma and its activity, and stimulated production of a low NO-producing population of monocytes, which allowed cysts rupture, increased parasite multiplication and finally reactivation of T. gondii infection. The immune studies performed in 4 subjects showed a decreased percentage of T lymphocytes, increased total number of lymphocytes B and serum IgM concentration, and impaired phagocytosis. In addition, few of them had also urinary tract diseases known to produce IL-6 that can mediate immunosuppressive functions, involving induction of the anti-inflammatory cytokine IL-10. These disturbances probably resulted from the host protective immune reactions associated with the chronic latent CNS T. gondii infection/inflammation. This is consistent with significantly lower enzyme indoleamine 2,3-dioxygenase (IDO) activity reported in atopic than in nonatopic individuals, and an important role that IDO and tryptophan degradation pathways plays in both, the host resistance to T. gondii infection and its reactivation. Analysis of literature information on the subjects with different types of headaches caused by foods, medications, and other substances, may suggest that their clinical symptoms and changes in laboratory data result at least in part from interference of these factors with dietary tryptophan biotransformation pathways. Several of these agents caused headache attacks through enhancing NO production via the conversion of arginine to citrulline and NO by the inducible nitric oxide synthase enzyme, which results in the high-output pathway of NO synthesis. This increased production of NO is, however, quickly down-regulated by NO itself because this biomolecule can directly inactivate NOS, may inhibit Ia expression on IFN-gamma-activated macrophages, which would limit antigen-presenting capability, and block T-cell proliferation, thus decreasing the antitoxoplasmatic activity. Moreover, NO inhibits IDO activity, thereby suppressing kynurenine formation, and at least one member of the kynurenine pathway, 3-hydroxyanthranilic acid, has been shown to inhibit NOS enzyme activity, the expression of NOS mRNA, and activation of the inflammatory transcription factor, nuclear factor-kB. In addition, the anti-inflammatory cytokines IL-4 and IL-10, TGF-beta, and a cytokine known as macrophage deactivating factor, have been shown to directly modulate NO production, sometimes expressing synergistic activity. On the other hand, IL-4 and TGF-beta can suppress IDO activity in some cells, for example human monocytes and fibroblasts, which is consistent with metabolic pathways controlled by IDO being a significant contributor to the proinflammatory system. Also, it seems that idiopathic intracranial hypertension, pseudotumor cerebri, and aseptic meningitis, induced by various factors, may result from their interference with IDO and inducible nitric oxide synthase activities, endogenous NO level, and cytokine irregularities which finally affect former T. gondii status 2mo in the brain. All these biochemical disturbances caused by the CNS T. gondii infection/inflammation may also be responsible for the relationship found between neurologic symptoms, such as headache, vertigo, and syncope observed in apparently immunocompetent children and adolescents, and physical and psychiatric symptoms in adulthood. We therefore believe that tests for T. gondii should be performed obligatorily in apparently immunocompetent patients with different types of headaches, even if they have no enlarged peripheral lymph nodes. This may help to avoid overlooking this treatable cause of the CNS disease, markedly reduce costs of hospitalization, diagnosis and treatment, and eventually prevent developing serious neurologic and psychiatric disorders.
Collapse
Affiliation(s)
- Joseph Prandota
- Faculty of Medicine and Dentistry, University Medical School, Wroclaw, Poland.
| |
Collapse
|
7
|
Milani E, Nikfar S, Khorasani R, Zamani MJ, Abdollahi M. Reduction of diabetes-induced oxidative stress by phosphodiesterase inhibitors in rats. Comp Biochem Physiol C Toxicol Pharmacol 2005; 140:251-5. [PMID: 15907769 DOI: 10.1016/j.cca.2005.02.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Revised: 02/12/2005] [Accepted: 02/14/2005] [Indexed: 10/25/2022]
Abstract
Increased oxidative stress has been suggested to be involved in the pathogenesis and progression of diabetic tissue damage. The aim of this study was to investigate the effect of different phosphodiesterase inhibitors on lipid peroxidation and total antioxidant capacity (TAC) of plasma in streptozotocin-induced diabetic rats (Rattus norvegicus). Rats became diabetic by a single administration of streptozotocin (STZ, 45 mg/kg). The effects of 15-days treatment by milrinone, sildenafil, and theophylline as cyclic-AMP and -GMP phosphodiesterase inhibitors (PDEIs) on diabetes-induced oxidative stress were studied. The levels of glucose, malonedialdehyde (MDA) the by product of lipid peroxides, and TAC (FRAP test) were estimated in plasma of control and experimental groups of rats. A significant increase in the levels of plasma glucose, and MDA and a concomitant decrease in the levels of TAC were observed in diabetic rats. These alterations were reverted back to near normal level after the treatment with PDEIs. Treatment of diabetic rats by PDEIs reduced MDA levels and increased TAC in the order of milrinone>sildenafil>theophylline. In conclusion, the present investigation show that PDIS possesses antioxidant activities, which may be attributed to their enhancing effect on cellular cyclic nucleotides contributing to the protection against oxidative stress in streptozotocin-induced diabetes. Exact mechanism of protective actions of cAMP- and cGMP-phosphodiesterase remains to be elucidated by further studies. This finding may suggest a place for PDEIs in maintaining health in diabetes.
Collapse
Affiliation(s)
- Elham Milani
- Laboratory of Toxicology, Department of Pharmacology and Toxicology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | | | | | | | | |
Collapse
|
8
|
Ito C, Yamamoto H, Furukawa Y, Takeda SI, Akimoto T, Iimura O, Ando Y, Asano Y, Kusano E. Role of cyclins in cAMP inhibition of glomerular mesangial cell proliferation. Clin Sci (Lond) 2004; 107:81-7. [PMID: 14992682 DOI: 10.1042/cs20030335] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2003] [Revised: 02/23/2004] [Accepted: 03/02/2004] [Indexed: 11/17/2022]
Abstract
MC (mesangial cell) proliferation is closely linked to the progression of glomerular disease. It has been reported that cAMP effectors suppress MC proliferation, inhibiting activation of MAPK (mitogen-activated protein kinase). In fibroblasts, activation of MAPK induces the expression of type D cyclin, whereas, in MCs, this induction has not been shown. In the present study, we explored the effects of cAMP on MAPK and expression of cell-cycle-regulated proteins. PDGF (platelet-derived growth factor) stimulated MAPK activity, up-regulated protein levels of cyclin D1, CDK2 (cyclin-dependent kinase 2) and PCNA (proliferating cell nuclear antigen), decreased the protein level of p27 and increased DNA synthesis. Fsk (forskolin) or PD98059 suppressed PDGF-induced DNA synthesis. Both agents inhibited PDGF-stimulated mRNA and protein expression of cyclin D1 and CDK2. Fsk or PD98059 also inhibited protein expression of PCNA and blocked a decrease in p27 protein. Fsk induced the phosphorylation of Raf-1 at Ser259, which was inhibited by KT5720. These data suggest that cAMP inhibits MC proliferation through inhibition of MAPK activity, and this mechanism partly involves alteration in the levels of cell-cycle-regulated proteins.
Collapse
Affiliation(s)
- Chiharu Ito
- Division of Nephrology, Department of Internal Medicine, Jichi Medical School, Tochigi, Japan. chiharu.@jichi.ac.jp
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Onozato ML, Tojo A, Goto A, Fujita T. Effect of combination therapy with dipyridamole and quinapril in diabetic nephropathy. Diabetes Res Clin Pract 2003; 59:83-92. [PMID: 12560157 DOI: 10.1016/s0168-8227(02)00154-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND/AIMS Dipyridamole stimulates nitric oxide action via inhibition of phosphodiesterase and also has an antioxidant effect. ACE inhibitor reduces glomerular pressure and enhances NO action via increased bradykinin. Thus, we evaluated the effect of the combination of dipyridamole and ACE inhibitor in diabetic nephropathy. METHODS Streptozotocin-induced diabetic rats at 2 weeks were treated with dipyridamole, quinapril or both. The expression of NOS and NAD(P)H oxidase p47phox was investigated using immunohistochemistry and western blot, and urinary albumin, cGMP and lipid peroxidation products (LPO) were measured at 4 weeks. RESULTS NAD(P)H oxidase and urinary LPO were significantly enhanced in diabetes, and suppressed by each treatment to the same extent. The nNOS expression in macula densa and eNOS increased significantly with combination therapy compared to quinapril treatment alone contributing to an enhanced urinary excretion of cGMP and to maintain the creatinine clearance. Increased albuminuria in diabetes was reduced more effectively with combination therapy to the control level than with single treatments. CONCLUSION Combination therapy with dipyridamole and quinapril suppressed urinary LPO via reduction of NAD(P)H oxidase increase in diabetes. The combination therapy reduced microalbuminuria to the control level and maintained creatinine clearance with enhanced nNOS and eNOS expression compared to quinapril alone.
Collapse
Affiliation(s)
- Maristela Lika Onozato
- Division of Nephrology and Endocrinology, Department of Internal Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan
| | | | | | | |
Collapse
|
10
|
Ito C, Kusano E, Furukawa Y, Yamamoto H, Takeda SI, Akimoto T, Iimura O, Ando Y, Asano Y. Modulation of the erythropoietin-induced proliferative pathway by cAMP in vascular smooth muscle cells. Am J Physiol Cell Physiol 2002; 283:C1715-21. [PMID: 12419709 DOI: 10.1152/ajpcell.00143.2002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously reported that erythropoietin (Epo) has a mitogenic effect on rat vascular smooth muscle cells (VSMC) and that activation of the mitogen-activated protein kinase (MAPK) cascade is an important mediator for Epo-induced mitogenesis. An increase in intracellular cAMP has an antiproliferative effect on VSMC. We therefore hypothesized that cAMP effectors inhibit Epo-induced MAPK activation in rat VSMC. When we exposed VSMC to recombinant human Epo (rHuEpo), DNA synthesis was increased. Forskolin (Fsk) or cilostazol (Cil) decreased the DNA synthesis stimulated by rHuEpo. Coincubation with Rp-cAMPS triethylamine canceled the suppression of DNA synthesis and MAPK activity by Fsk. Both rHuEpo and phorbol 12-myristate 13-acetate upregulated phosphorylations of MEK and MAPK. Pretreatment with Fsk inhibited these phosphorylations. Protein kinase C inhibitors also suppressed MEK and MAPK phosphorylations. Moreover, Fsk induced phosphorylation of Raf-1 at serine-259. These results indicated that cAMP inhibited Epo-induced MAPK activation and that this suppression might be regulated upstream or at Raf-1. The results also suggested that these agents, which could accumulate cAMP, might be protective for Epo-stimulated direct action.
Collapse
Affiliation(s)
- Chiharu Ito
- Division of Nephrology, Department of Internal Medicine, Jichi Medical School, Tochigi 329-0498, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Hewitson TD, Tait MG, Kelynack KJ, Martic M, Becker GJ. Dipyridamole inhibits in vitro renal fibroblast proliferation and collagen synthesis. ACTA ACUST UNITED AC 2002; 140:199-208. [PMID: 12271277 DOI: 10.1067/mlc.2002.126828] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fibroblasts are universally recognized in situations of tubulointerstitial injury, where their presence has been shown to be a marker of disease progression. The objective of this study was to determine whether the functions of fibroblasts relevant to fibrogenesis can be modified in vitro with dipyridamole. Cells were obtained from obstructed rat renal tissue and characterized on the basis of immunohistochemical findings. Fibroblasts constituted all of the cells from passage 3. Functional parameters were measured in cells cultured with 1, 5, and 50 micromol/L dipyridamole and compared to basal parameters of cells grown in Dulbecco's modified Eagle's medium plus 10% fetal calf serum (control). Northern-blot analysis indicated that dipyridamole decreased procollagen alpha1(I) messenger ribonucleic acid expression (P <.05, 50 micromol/L vs control), results that were reflected in a reduction in total collagen secretion as measured on the basis of hydroxyproline incorporation (P <.001, 50 micromol/L vs control). Mitogenesis, as measured on the basis of incorporation of tritiated thymidine, was decreased in a dose-dependent fashion by dipyridamole. Likewise, 50 micromol/L dipyridamole reduced cell-population growth to 16.8% +/- 2.1% of basal growth over 3 days (P <.001 vs control). Effects of dipyridamole on population growth were prevented by coincubation with a protein kinase G inhibitor peptide (P <.001 vs 50 micromol/L dipyridamole; P = not significant vs control). No such effect was observed with inhibitors for protein kinase A (H-89) and protein kinase C (bisindolylmaleimide I). Consistent with a protein kinase G-dependent mechanism, immunofluorescence staining indicated that dipyridamole increased basal expression of the inducible form of nitric oxide synthase. In conclusion, the results of this study demonstrate that at clinically relevant concentrations, dipyridamole inhibits profibrotic activities of renal fibroblasts. Effects on mitogenesis are mediated through a cyclic guanosine monophosphate-protein kinase G effector pathway.
Collapse
Affiliation(s)
- Tim D Hewitson
- Department of Nephrology, Royal Melbourne Hospital; and Department of Medicine, University of Melbourne, Melbourne, Australia.
| | | | | | | | | |
Collapse
|
12
|
Ito C, Kusano E, Akimoto T, Takeda S, Sasaki N, Umino T, Iimura O, Ando Y, Asano Y. Cilostazol enhances IL-1beta-induced NO production and apoptosis in rat vascular smooth muscle via PKA-dependent pathway. Cell Signal 2002; 14:625-32. [PMID: 11955955 DOI: 10.1016/s0898-6568(02)00004-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Interleukin-1beta (IL-1beta) stimulates nitric oxide (NO) production and induces apoptosis in several tissues. Cilostazol is a Type 3 phosphodiesterase inhibitor. We investigated whether cilostazol affects IL-1beta-induced NO production and apoptosis in rat vascular smooth muscle cells. Cilostazol (100 nM-10 microM) potentiated NO production triggered by IL-1beta. The mRNA and protein expression of inducible NO synthase was also upregulated by cilostazol. KT5720, an inhibitor of protein kinase A, and N(G)-monomethyl-L-arginine, an inhibitor of NO synthase, abrogated cilostazol-enhanced IL-1beta-stimulated NO production and apoptosis. These results shows that cilostazol potentiates IL-1beta-induced NO production via PKA-pathway and thereafter augments apoptosis via NO-dependent pathway.
Collapse
MESH Headings
- Animals
- Apoptosis
- Cells, Cultured
- Cilostazol
- Cyclic AMP-Dependent Protein Kinase Type II
- Cyclic AMP-Dependent Protein Kinases/physiology
- Dose-Response Relationship, Drug
- Drug Synergism
- Interleukin-1/pharmacology
- Kinetics
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/metabolism
- Nitric Oxide/biosynthesis
- Nitric Oxide Synthase/biosynthesis
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase Type II
- Nitrites/analysis
- Phosphodiesterase Inhibitors/pharmacology
- RNA, Messenger/biosynthesis
- Rats
- Rats, Sprague-Dawley
- Signal Transduction
- Tetrazoles/pharmacology
Collapse
Affiliation(s)
- Chiharu Ito
- Department of Nephrology, Jichi Medical School, Yakushiji 3311-1, Minamikawachi, 329-0498, Tochigi, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Hung KY, Shyu RS, Fang CC, Tsai CC, Lee PH, Tsai TJ, Hsieh BS. Dipyridamole inhibits human peritoneal mesothelial cell proliferation in vitro and attenuates rat peritoneal fibrosis in vivo. Kidney Int 2001; 59:2316-24. [PMID: 11380836 DOI: 10.1046/j.1523-1755.2001.00749.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Peritoneal fibrosis (PF) is one of the most serious complications after long-term continuous ambulatory peritoneal dialysis (CAPD). Proliferation of human peritoneal mesothelial cells (HPMC) and matrix over-production are regarded as the main processes predisposing to PF. Dipyridamole (DP) has been reported to have potential as an antiproliferative and antifibrotic agent. We thus investigated the effect of DP in inhibiting proliferation and collagen synthesis of HPMC. A rat model of peritonitis-induced PF was also established to demonstrate the in vivo preventive effect of DP. METHODS HPMC was cultured from human omentum by an enzyme digestion METHOD Cell proliferation was measured by the methyltetrazolium assay. Intracellular cAMP was measured using an enzyme immunoassay (EIA) kit. Total collagen synthesis was measured by (3)H-proline incorporation assay. Expression of collagen alpha1 (I) and collagen alpha 1 (III) mRNAs was determined by Northern blotting. The rat model of peritonitis-induced PF was developed by adding dextran microbeads (Cytodex, 8 mg/1 mL volume) to a standardized suspension (3 x 10(9)) of Staphylococcus aureus. DP was administrated via intravenous infusion (4 mg in 1 h) daily for seven days. Macroscopic grading of intraperitoneal adhesions and histological analyses of peritoneal thickness and collagen expression were performed. RESULTS Addition of DP to HPMC cultures suppressed serum-stimulated cell proliferation and collagen synthesis. The antimitogenic and antifibrotic effects of DP appear to be predominantly mediated through the cAMP pathway, as DP increased intracellular cAMP in a dose-dependent manner. The macroscopic grade of intraperitoneal adhesion and peritoneal thickness were both significantly increased in animals treated with Cytodex plus S. aureus; on the other hand, DP attenuated these fibrotic changes with statistical significance (P < 0.01). Analysis of gene expression of collagen alpha 1 (I) and alpha1 (III) in the peritoneal tissue of experimental animals yielded similar results. CONCLUSIONS This study suggests that dipyridamole may have therapeutic potential in treating peritoneal fibrosis.
Collapse
Affiliation(s)
- K Y Hung
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, Republic of China
| | | | | | | | | | | | | |
Collapse
|
14
|
Akimoto T, Kusano E, Fujita N, Okada K, Saito O, Ono S, Ando Y, Homma S, Saito T, Asano Y. Erythropoietin modulates angiotensin II- or noradrenaline-induced Ca(2+) mobilization in cultured rat vascular smooth-muscle cells. Nephrol Dial Transplant 2001; 16:491-9. [PMID: 11239021 DOI: 10.1093/ndt/16.3.491] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND It has been reported that human recombinant erythropoietin (rHuEpo) modulates the sensitivity of the cardiovascular system to angiotensin II (Ang II) or noradrenaline (NA). In the present study, we explored the effect of rHuEpo on the responsiveness of Ang II- or NA-induced cytosolic free calcium ([Ca(2+)]i) mobilization in cultured rat vascular smooth-muscle cells (VSMC). METHODS [Ca(2+)]i concentrations in VSMC were measured by using the calcium-sensitive fluorescent dye fura-2. RESULTS The addition of rHuEpo (250 U/ml) alone induced elevation in [Ca(2+)]i, which remained significantly elevated above basal level for at least 60 min in the presence of extracellular Ca(2+). Pre-incubation with specific protein kinase C (PKC) inhibitor calphostin C (1 micromol/l) significantly reduced the peak and the sustained elevations of [Ca(2+)]i. Pre-treatment with rHuEpo for 60 min increased both basal [Ca(2+)]i and the changes in [Ca(2+)]i by Ang II or NA in a dose-dependent manner in the presence of extracellular Ca(2+). The synergistic effects of rHuEpo with Ang II or NA were also retained when VSMC were bathed in the Ca(2+)-free medium after the pre-incubation of rHuEpo. Conversely, they were diminished in the presence of extracellular Ca(2+) combined with intracellular Ca(2+) release inhibitor 8-(NN-diethylamino)octyl-1,3,4,5-trimethoxybenzoate (TMB-8). The synergistic effects of rHuEpo were also diminished by PKC depletion or by PKC inhibitor. CONCLUSIONS These observations suggest that rHuEpo has synergistic effects on Ang II- or NA-induced [Ca(2+)]i mobilization, particularly on intracellular Ca(2+) release, in VSMC. This may be a potential mechanism contributing to hypertension associated with rHuEpo therapy.
Collapse
Affiliation(s)
- T Akimoto
- Department of Nephrology, Jichi Medical School, Tochigi, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
|
16
|
Akimoto T, Kusano E, Ito C, Yanagiba S, Inoue M, Amemiya M, Ando Y, Asano Y. Involvement of erythropoietin-induced cytosolic free calcium mobilization in activation of mitogen-activated protein kinase and DNA synthesis in vascular smooth muscle cells. J Hypertens 2001; 19:193-202. [PMID: 11212961 DOI: 10.1097/00004872-200102000-00005] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND/OBJECTIVE Human recombinant erythropoietin (rHuEPO) induces cytosolic free calcium ([Ca2+]i) mobilization, an activation of mitogen-activated protein (MAP) kinase and DNA synthesis in several tissues. We explored the mechanism of rHuEPO-induced [Ca2+]i mobilization and its role in the activation of MAP kinase and DNA synthesis in vascular smooth muscle cells (VSMC). METHODS [Ca2+]i concentrations were measured by fura-2. MAP kinase activation was analyzed using an immunocomplex kinase assay and Western blotting. DNA synthesis was measured as an incorporation of 5-bromo-2'-deoxyuridine. RESULTS Although addition of rHuEPO significantly increased [Ca2+]i, either in the presence or absence of extracellular Ca2+, the peak level and sustained elevation of [Ca2+]i were significantly reduced in the absence of extracellular Ca2+. Pretreatment with genistein completely blocked the elevation of [Ca2+]i in both conditions. Calphostin C and staurosporine did not completely block the elevation of [Ca2+]i. Staurosporine reduced its peak level in a dose-dependent manner, whereas calphostin C reduced its peak level at concentrations over 1 nmol/l in the presence of extracellular Ca2+. Similar results to those with staurosporine were observed with nifedipine. In the absence of extracellular Ca2+, their dose-dependent effects disappeared even though rHuEPO increased [Ca2+]i. rHuEPO activated MAP kinase and DNA synthesis, both of which were significantly suppressed by the chelation of intracellular Ca2+. CONCLUSION These findings suggest that rHuEPO increases [Ca2+]i by both Ca2+ influx and Ca2+ release from intracellular stores. Tyrosine phosphorylation is critical in the regulation of [Ca2+]i, but protein kinase C activation is important only in the regulation of Ca2+ influx. Dihydropyridine-sensitive L-type Ca2+ channels seem to be involved in rHuEPO-induced Ca2+ influx. In addition, increase of [Ca2+]i by rHuEPO stimulates MAP kinase activation and DNA synthesis in VSMC.
Collapse
Affiliation(s)
- T Akimoto
- Department of Nephrology, Jichi Medical School, Minamikawachi, Tochigi, Japan
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Pacheco ME, Marín J, Manso AM, Rodríguez-Martínez MA, Briones A, Salaices M, Redondo J. Nitric oxide synthase induction by ouabain in vascular smooth muscle cells from normotensive and hypertensive rats. J Hypertens 2000; 18:877-84. [PMID: 10930185 DOI: 10.1097/00004872-200018070-00009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To investigate the effect of ouabain on inducible nitric oxide synthase (iNOS) activity and expression in cytokine-stimulated vascular smooth muscle cells (VSMC) from normotensive Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). METHODS VSMC were treated for 24 h and afterwards, nitric oxide (NO) release was determined by the production of nitrite, a stable metabolite of NO. Activity of iNOS was measured by the conversion of [3H]-L-arginine to [3H]-L-citrulline and iNOS protein expression by Western blotting. RESULTS Ouabain (0.01-1 mmol/l) further enhanced interleukin-1beta (II-1beta)-induced nitrite production by WKY and SHR VSMC, although a more pronounced effect was observed in SHR cells (maximum response 52.1 +/- 5.2 and 71.2 +/- 6.4% of 11-1beta effect in WKY and SHR cells, respectively). Such response on NO release was mimicked by the calcium ionophore A 23187 (0.01-1 micromol/l) and abolished by the voltage-operated calcium channels (VOCC) nifedipine (0.1 micromol/l). Expression of iNOS showed that ouabain increased the synthesis of the enzyme in WKY and SHR VSMC stimulated with II-1beta, and this effect was higher in SHR cells. The increased iNOS expression was significantly reduced by nifedipine. CONCLUSIONS Ouabain stimulation of iNOS expression and activity in II-1beta-stimulated VSMCs from WKY rats and SHR seems to be related to increased intracellular calcium influx through VOCC. The more pronounced effect observed in SHR VSMC could be explained by an altered calcium entry in the hypertensive strain.
Collapse
Affiliation(s)
- M E Pacheco
- Departamento de Farmacologia y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Spain
| | | | | | | | | | | | | |
Collapse
|
18
|
Akimoto T, Kusano E, Inaba T, Iimura O, Takahashi H, Ikeda H, Ito C, Ando Y, Ozawa K, Asano Y. Erythropoietin regulates vascular smooth muscle cell apoptosis by a phosphatidylinositol 3 kinase-dependent pathway. Kidney Int 2000; 58:269-82. [PMID: 10886572 DOI: 10.1046/j.1523-1755.2000.00162.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Recent studies have shown that several cytokines could induce apoptosis in vascular smooth muscle cells (VSMCs) via the induction of nitric oxide (NO). In the present study, we explored whether human recombinant erythropoietin (rHuEPO) has a modulatory effect of apoptosis on interleukin-1beta (IL-1beta) or NO donor sodium nitroprusside (SNP)-induced apoptosis in rat cultured VSMCs. METHODS The quantitation of apoptosis among VSMCs was assessed by nuclear morphological analysis with fluorescent DNA-binding dye Hoechst 33258. Apoptotic changes were also confirmed by the detection of DNA fragmentation. The expression of EPO receptor (EpoR), cellular protein tyrosine phosphorylation, including EpoR and Janus kinase (JAK) 2, and the association of p85 subunit of phosphatidylinositol 3 kinase (PI3-kinase) to tyrosine-phosphorylated proteins, including EpoR, were explored by using Western blotting analysis combined in part with immunoprecipitation. RESULTS rHuEPO inhibited the apoptosis induced by IL-1beta or SNP in a dose- and time-dependent manner. The anti-apoptotic effects of rHuEPO were diminished in the presence of a tyrosine kinase (TK) inhibitor genistein or anti-EpoR antibody. After stimulation with rHuEPO, EpoR and JAK 2 were tyrosine phosphorylated, and p85 subunits were associated with EpoR. Also, rHuEPO induced phosphorylation of Akt through a PI3-kinase-dependent pathway. The phosphorylation of Akt and the anti-apoptotic effects of rHuEPO were diminished in the presence of a PI3-kinase inhibitor, wortmannin. CONCLUSION Our present study demonstrates that rHuEPO inhibites IL-1beta or SNP-induced VSMC apoptosis. The TK-dependent pathway, particularly the PI3-kinase-dependent pathway, seems to be critical to the countervailing effect of rHuEPO on IL-1beta and SNP-induced VSMC apoptosis.
Collapse
Affiliation(s)
- T Akimoto
- Departments of Nephrology and Molecular Biology, Jichi Medical School, Tochigi, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
De La Cruz JP, Blanco E, Sánchez de la Cuesta F. Effect of dipyridamole and aspirin on the platelet-neutrophil interaction via the nitric oxide pathway. Eur J Pharmacol 2000; 397:35-41. [PMID: 10844096 DOI: 10.1016/s0014-2999(00)00245-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study was designed to determine the influence of the combination of aspirin and dipyridamole on the interaction in vitro between neutrophils and platelets through the nitric oxide (NO) pathway. Collagen-induced platelet aggregation (impedance method) was determined in platelet-rich plasma and in platelet-rich plasma+neutrophils, and cGMP (enzyme immunoanassay) and NO levels (electrochemical method, with a ISO-200 electrode) were also measured. The 50% inhibitory concentration (IC(50)) of aspirin was 139+/-11 microM in platelet-rich plasma, 367+/-21 microM in platelet-rich plasma+L-N(G)-nitro-arginine-methyl-ester (L-NAME), and 42+/-3 microM in platelet-rich plasma+L-arginine. The IC(50) for dipyridamole in platelet-rich plasma was not affected by L-NAME or L-arginine; the combination of aspirin with 20 microM dipyridamole (which has no effect per se) led to an IC(50) of 51+/-2 microM in platelet-rich plasma, 101+/-7 microM in platelet-rich plasma+L-NAME, and 13+/-2 microM in platelet-rich plasma+L-arginine. The cGMP levels showed the greatest increases in the aspirin plus dipyridamole group. Dipyridamole and aspirin increased the leukocyte production of NO: 50% increases were obtained at concentrations of 285+/-31 microM aspirin, 110+/-9 microM dipyridamole, and 16+/-2 microM aspirin+dipyridamole. Dipyridamole alone at a concentration of 20 microM had no significant effect on NO levels. We conclude that the combination of aspirin and dipyridamole significantly increases the antiplatelet effect of leukocytes, through an increase of NO, and that this effect is further evidence of the therapeutic benefits of this combination of drugs.
Collapse
Affiliation(s)
- J P De La Cruz
- Department of Pharmacology and Therapeutics, School of Medicine, University of Málaga, Campus de Teatinos s/n, 29071, Málaga, Spain.
| | | | | |
Collapse
|
20
|
Galea E, Feinstein DL. Regulation of the expression of the inflammatory nitric oxide synthase (NOS2) by cyclic AMP. FASEB J 1999; 13:2125-37. [PMID: 10593859 DOI: 10.1096/fasebj.13.15.2125] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The enzyme nitric oxide synthase 2 (NOS2), often called inducible NOS, plays a central role in the inflammatory reactions that follow infection or tissue damage. NOS2 has been detected in virtually every cell type, and the NO it produces can perform both beneficial and detrimental actions. It is thus conceivable that regulatory mechanisms exist which control the timing and intensity of NO production by NOS2 in order to outweigh protective effects against detrimental ones. Since cyclic AMP inhibits numerous immunological reactions, studies have been carried out to determine whether cAMP-dependent pathways could inhibit NOS2 expression as well. Pharmacological studies in cultured cells show that, depending on the cell type examined, increased cAMP can exert opposite effects on the endotoxin- or cytokine-induced expression of NOS2, being either stimulatory or inhibitory in macrophages, stimulatory in adipocytes, smooth muscle, skeletal muscle, and brain endothelial cells, and inhibitory in pancreatic, liver, and brain glial cells. Regulation of NOS2 gene transcription appears to be the primary mechanism of action of cAMP, and whether it is stimulatory or inhibitory hinges on the cell-specific regulation of transcription factors including CREB, NF-kappaB, and C/EBP. Cyclic AMP must therefore be considered a modulator rather than a suppressor of NOS2 expression. This review summarizes evidence derived from in vitro studies, considers regulation of NOS2 by cAMP in vivo, and discusses possible therapeutic applications of cAMP treatment.-Galea, E., Feinstein, D. L. Regulation of the expression of the inflammatory nitric oxide synthase (NOS2) by cyclic AMP.
Collapse
Affiliation(s)
- E Galea
- Department of Anesthesiology, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
| | | |
Collapse
|
21
|
Akimoto T, Kusano E, Muto S, Fujita N, Okada K, Saito T, Komatsu N, Ono S, Ebata S, Ando Y, Homma S, Asano Y. The effect of erythropoietin on interleukin-1beta mediated increase in nitric oxide synthesis in vascular smooth muscle cells. J Hypertens 1999; 17:1249-56. [PMID: 10489101 DOI: 10.1097/00004872-199917090-00003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Recently, we observed that recombinant human erythropoietin (rHuEPO) inhibits the interleukin (IL)-1beta induced nitric oxide (NO) production and inducible NO synthase (iNOS) expression in cultured rat vascular smooth muscle cells (VSMC). The mechanisms of these inhibitory effects of rHuEPO were evaluated. METHODS Reverse transcription-polymerase chain reaction (RT-PCR) was performed to identify a specific erythropoietin receptor (EpoR). Tyrosine phosphorylation of phospholipase C (PLC) was analyzed by combination of immunoprecipitation and Western blotting. Protein kinase C (PKC) activities were analyzed by phosphorylation assay of myelin basic protein (MBP4-14). VSMC were incubated with test agents for 24 h and nitrite as a stable NO metabolite was measured. iNOS mRNA and protein expression was analyzed by Northern and Western blotting, respectively. RESULTS RT-PCR analysis revealed that EpoR m-RNA was expressed; furthermore, it might be alternatively spliced in VSMC. rHuEPO induced tyrosine phosphorylation of PLC-gamma1 and activation of PKC. rHuEPO inhibited not only IL-1beta induced nitrite production, but also the expression of iNOS mRNA and protein. These inhibitory effects of rHuEPO were reversed in the presence of PKC inhibitors, calphostin C (1 pmol/l) or staurosporine (10 nmol/l). PKC activation by phorbol myristate acetate inhibited nitrite production. The inhibitory effect of rHuEPO on IL-1beta induced nitrite production was also eliminated in PKC depleted cells or in the existence of anti-EpoR antibody. CONCLUSION rHuEPO inhibits IL-1beta induced NO production by suppressing iNOS mRNA and protein expressions through EpoR, and the PLC-gamma1 and PKC pathway may be involved.
Collapse
MESH Headings
- Animals
- Antibodies/pharmacology
- Cells, Cultured
- Enzyme Activation/drug effects
- Erythropoietin/pharmacology
- Humans
- Interleukin-1/antagonists & inhibitors
- Interleukin-1/pharmacology
- Isoenzymes/metabolism
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/metabolism
- Nitric Oxide/biosynthesis
- Nitric Oxide Synthase/biosynthesis
- Nitric Oxide Synthase Type II
- Phospholipase C gamma
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C/metabolism
- RNA, Messenger/biosynthesis
- Rats
- Receptors, Erythropoietin/biosynthesis
- Receptors, Erythropoietin/immunology
- Receptors, Erythropoietin/metabolism
- Recombinant Proteins
- Type C Phospholipases/metabolism
Collapse
Affiliation(s)
- T Akimoto
- Department of Nephrology, Jichi Medical School, Tochigi, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Hayden MA, Nakayama DK. Cyclic nucleotides and inducible nitric oxide synthesis in pulmonary artery smooth muscle. J Surg Res 1999; 82:222-7. [PMID: 10090833 DOI: 10.1006/jsre.1999.5573] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Nitric oxide (NO), cGMP, and cAMP affect the synthesis, metabolism, and cellular effects each other. We wanted to study how cGMP and cAMP interact to affect the induced synthesis of NO in response to interleukin-1 beta (IL-1 beta) in rat pulmonary artery smooth muscle cells. To further dissect the relative contributions of each cyclic nucleotide, and to detect any possible "crossover" effect of one cyclic nucleotide activating the other protein kinase, we tested how pharmacological inhibition of cGMP-dependent and cAMP-dependent protein kinases (PKG and PKA, respectively) affected responses. MATERIALS AND METHODS We tested the effects of IL-1 beta, dibutyryl (db)-cAMP (1-100 micro) and 8-bromo (Br)-cGMP (1 microM-1 mM) on NO synthesis in cultured rat pulmonary artery smooth muscle cells. Positive effects were then tested in the presence of KT5720 (10(-9)-10(-5) M), the pharmacological inhibitor of PKA, and KT5823 (10(-9)-10(-5) M), the pharmacological inhibitor of PKG. NO production was measured using the Greiss reaction, and mRNA abundance of the inducible NO synthase (iNOS), using semiquantitative RT-PCR. RESULTS IL-1 beta caused nitrite levels to increase nearly 10-fold over basal levels at 24 h (P < 0.05). Nitrite levels increased with the addition of either db-cAMP (100 microM, an 8-fold increase) or 8-Br-cGMP (100 microM, a 3-fold increase) to IL-1 beta (P < 0.05). PKA inhibition with KT5720 (10(-5) M) completely inhibited NO synthesis in response to the combination of IL-1 beta and cAMP, while KT5823 had less effect at all doses tested. NO synthesis in response to IL-1 beta plus cGMP also decreased to PKA inhibition, but not PKG inhibition, indicating that cGMP responses are a crossover effect. Both cAMP and cGMP in combination with IL-1 beta increased iNOS mRNA abundance above basal levels on reverse transcription polymerase chain reaction. KT5720, but not KT5823, decreased iNOS mRNA to basal levels. CONCLUSION Both cAMP and cGMP augment cytokine induction of NO synthesis through activation of PKA: cAMP does so directly; cGMP, through a crossover stimulation of PKA.
Collapse
Affiliation(s)
- M A Hayden
- Section of Pediatric Surgery and the Department of Surgery, University of North Carolina at Chapel Hill, C.B. 7210, 3010 Old Clinics Building, Chapel Hill, North Carolina, 27599-7210, USA
| | | |
Collapse
|
23
|
Kuriyama S, Tomonari H, Hosoya T. Antiplatelet therapy decreases the incidence of erythropoietin-induced hypertension in predialysis patients. Clin Exp Hypertens 1999; 21:213-22. [PMID: 10225477 DOI: 10.3109/10641969909068662] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The observation that antiplatelet therapy may decrease the incidence of Epo-induced hypertension in dialysis patients remains a subject of particular interest. The aim of the present study was to test this hypothesis in patients at the predialysis stage. Predialysis patients with renal anemia were treated with EPO (6000 IU/week) for 6-12 months. Patients were divided into two groups, one of which received antiplatelet therapy and the other did not, and a comparison was made between them with respect to the incidence of EPO-induced hypertension. Logistic regression analysis was used to determine the risk factors for developing hypertension during the EPO therapy. Such predictors included age, gender, antecedent of hypertension, antiplatelet drugs and diabetes mellitus. Overall, 66 patients were enrolled in the study and 18 developed hypertension (27%). Out of the 35 patients not receiving antiplatelet therapy, 15 developed hypertension (43%). In contrast, out of the 31 patients receiving antiplatelet therapy, only 3 (10%) developed hypertension (p=0.003 by Chi square test). Multiple regression analysis showed that the best predictive variables for the development of hypertension were antecedent of hypertension (odds ratio: 0.064, p=0.0118), and use of antiplatelet drugs (odds ratio: 5.081, p=0.0295). The present data provide evidence that antiplatelet therapy may prevent EPO-induced hypertension in predialysis patients. However, the mechanism to explain such an effect still remains to be elucidated.
Collapse
Affiliation(s)
- S Kuriyama
- Division of Nephrology, Saiseikai Central Hospital, Tokyo, Japan
| | | | | |
Collapse
|
24
|
Umino T, Kusano E, Muto S, Akimoto T, Yanagiba S, Ono S, Amemiya M, Ando Y, Homma S, Ikeda U, Shimada K, Asano Y. AVP inhibits LPS- and IL-1beta-stimulated NO and cGMP via V1 receptor in cultured rat mesangial cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:F433-41. [PMID: 10070167 DOI: 10.1152/ajprenal.1999.276.3.f433] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study examined how arginine vasopressin (AVP) affects nitric oxide (NO) metabolism in cultured rat glomerular mesangial cells (GMC). GMC were incubated with test agents and nitrite, and intracellular cGMP content, inducible nitric oxide synthase (iNOS) mRNA, and iNOS protein were analyzed by the Griess method, enzyme immunoassay, and Northern and Western blotting, respectively. AVP inhibited lipopolysaccharide (LPS)- and interleukin-1beta (IL-1beta)-induced nitrite production in a dose- and time-dependent manner, with concomitant changes in cGMP content, iNOS mRNA, and iNOS protein. This inhibition by AVP was reversed by V1- but not by oxytocin-receptor antagonist. Inhibition by AVP was also reproduced on LPS and interferon-gamma (IFN-gamma). Protein kinase C (PKC) inhibitors reversed AVP inhibition, whereas PKC activator inhibited nitrite production. Although dexamethasone and pyrrolidinedithiocarbamate (PDTC), inhibitors of nuclear factor-kappaB, inhibited nitrite production, further inhibition by AVP was not observed. AVP did not show further inhibition of nitrite production with actinomycin D, an inhibitor of transcription, or cycloheximide, an inhibitor of protein synthesis. In conclusion, AVP inhibits LPS- and IL-1beta-induced NO production through a V1 receptor. The inhibitory action of AVP involves both the activation of PKC and the transcription of iNOS mRNA in cultured rat GMC.
Collapse
Affiliation(s)
- T Umino
- Department of Nephrology, Jichi Medical School, Tochigi, 329-0498 Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Kusano E, Tian S, Umino T, Tetsuka T, Ando Y, Asano Y. Arginine vasopressin inhibits interleukin-1 beta-stimulated nitric oxide and cyclic guanosine monophosphate production via the V1 receptor in cultured rat vascular smooth muscle cells. J Hypertens 1997; 15:627-32. [PMID: 9218182 DOI: 10.1097/00004872-199715060-00009] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND It has been reported that various vasoactive substance modulate cytokine stimulated nitric oxide (NO) production in many cell types. OBJECTIVE To examine the effects of arginine vasopressin (AVP) on the production of NO and cyclic GMP (cGMP), and on inducible nitric oxide synthase (INOS) in cultured rat vascular smooth muscle cells (VSMC). DESIGN Because VSMC possess the V1 receptor which clauses vascular contraction and respond to various cytokines for producing NO, we used rat VSMC and selected interleukin-1 beta (IL-1 beta) as a potent stimulator of NO production among various cytokines. We also measured cGMP production, which is the final mediator of NO-induced vascular relaxation, in order to evaluate the physiologic meaning of the present study. METHODS VSMC were incubated with test agents for 24 h except for a time-course study. Nitrite as a stable end product of NO was measured in the medium. Intracellular cGMP contents were assayed by enzyme immunoassay. INOS messenger RNA expression was analyzed by Northern blotting. RESULTS AVP inhibited IL-1 beta-induced nitrite production in a dose- and time-dependent manner with concomitant changes in intracellular cGMP contents. On the other hand, AVP did not affect nitrite and cGMP production in the absence of IL-1 beta. Inhibition of nitrite and cGMP production by AVP was reversed by administration of the specific V1 receptor antagonist [1-(beta-mercapto-beta,beta- cyclopentamethylene propionic acid), 2-(O-methyl)-tyrosine] -Arg8-vasopressin) but not by the oxytocin (OXT) receptor antagonist [d(CH2(5)), TyrMe2, Orn8]-Vasotocin. Administration of the V1 receptor antagonist or OXT receptor antagonist alone did not affect IL-1 beta-stimulated nitrite and cGMP production. Although administration of AVP inhibited IL-1 beta-induced INOS messenger RNA expression, administration of the V1 receptor antagonist but not of the OXT receptor antagonist reversed this inhibition. CONCLUSION It is suggested that AVP inhibits IL-1 beta-induced NO and cGMP production via the V1 receptor but not via the OXT receptor in VSMC. AVP can cause vascular contraction not only through direct action but also through indirect action by inhibiting NO production under some inflammatory conditions.
Collapse
MESH Headings
- Animals
- Antidiuretic Hormone Receptor Antagonists
- Arginine Vasopressin/administration & dosage
- Arginine Vasopressin/pharmacology
- Cells, Cultured
- Cyclic GMP/biosynthesis
- Dose-Response Relationship, Drug
- Interleukin-1/pharmacology
- Kinetics
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nitric Oxide/biosynthesis
- Rats
- Receptors, Oxytocin/antagonists & inhibitors
- Receptors, Oxytocin/drug effects
- Receptors, Oxytocin/metabolism
- Receptors, Vasopressin/drug effects
- Receptors, Vasopressin/metabolism
Collapse
Affiliation(s)
- E Kusano
- Department of Nephrology, Jichi Medical School, Tochigi, Japan
| | | | | | | | | | | |
Collapse
|
26
|
Nitric oxide in blood pressure regulation, with special reference to patients undergoing hemodialysis. Clin Exp Nephrol 1997. [DOI: 10.1007/bf02480650] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|