1
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Wang Y, Payne SJ. Static autoregulation in humans. J Cereb Blood Flow Metab 2023:271678X231210430. [PMID: 37933742 DOI: 10.1177/0271678x231210430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
The process by which cerebral blood flow (CBF) remains approximately constant in response to short-term variations in arterial blood pressure (ABP) is known as cerebral autoregulation. This classic view, that it remains constant over a wide range of ABP, has however been challenged by a growing number of studies. To provide an updated understanding of the static cerebral pressure-flow relationship and to characterise the autoregulation curve more rigorously, we conducted a comprehensive literature research. Results were based on 143 studies in healthy individuals aged 18 to 65 years. The mean sensitivities of CBF to changes in ABP were found to be 1.47 ± 0.71%/% for decreased ABP and 0.37 ± 0.38%/% for increased ABP. The significant difference in CBF directional sensitivity suggests that cerebral autoregulation appears to be more effective in buffering increases in ABP than decreases in ABP. Regression analysis of absolute CBF and ABP identified an autoregulatory plateau of approximately 20 mmHg (ABP between 80 and 100 mmHg), which is much smaller than the widely accepted classical view. Age and sex were found to have no effect on autoregulation strength. This data-driven approach provides a quantitative method of analysing static autoregulation that can be easily updated as more experimental data become available.
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Affiliation(s)
- Yufan Wang
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Stephen J Payne
- Institute of Applied Mechanics, National Taiwan University, Taipei
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2
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Wahood W, Ghozy S, Al-Abdulghani A, Kallmes DF. Radial artery diameter: a comprehensive systematic review of anatomy. J Neurointerv Surg 2022; 14:1274-1278. [PMID: 35169033 DOI: 10.1136/neurintsurg-2021-018534] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/03/2022] [Indexed: 01/22/2023]
Abstract
AIMS The objective of this systematic review is to determine with the highest accuracy the average radial artery (RA) diameter overall and in certain subgroups. The aim of this study is to provide assistance in the development of fitting transradial devices, an increasingly popular intervention. METHODS Several databases were used to extract appropriate studies highlighting RA diameter. Databases used in the generation of this study were Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus and Web of Science Core Collection. RA diameter was determined overall, in males versus females, adults only, adults+children, in the presence of comorbidities, and finally RA diameter in the context of various vasodilators. RESULTS A total of 71 studies were included. The average RA diameter overall was determined to be 2.62±0.15 mm in children+adults and 2.70±0.15 mm in adults only. In comparison to an RA diameter of 2.68±0.24 mm in adult males, the diameter was found to be 2.27±0.27 mm in adult females (p=0.028). As for comorbidities, the mean RA diameter in adult patients with hypertension and congestive heart failure was 2.72±0.37 mm and 2.80±0.25 mm, respectively. Finally, the mean RA diameter with nitrate and angiotensin-converting enzyme (ACE) inhibitor use was 2.97±0.53 mm and 2.82±0.29 mm respectively. For comparison, the average outer diameter of a 5 French introducer sheath is 2.29 mm and a 6 French introducer sheath is 2.62 mm. CONCLUSIONS The findings presented in this study will help determine the most appropriate transradial device to use in several different populations in the context of vasodilator usage or the absence thereof.
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Affiliation(s)
- Waseem Wahood
- Dr. Kiran C. Patel College of Allopathic Medicine, Nova Southeastern University, Fort Lauderdale, Florida, USA
| | - Sherief Ghozy
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Abdulaziz Al-Abdulghani
- Department of Neurology and Ophthalmology, Michigan State University, East Lansing, Michigan, USA
| | - David F Kallmes
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
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3
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Jeong S, Pollin KU, DuBose LE, Bunsawat K. Brain Blood Flow: The More You N.O. J Physiol 2022; 600:11-13. [PMID: 34863039 PMCID: PMC8724410 DOI: 10.1113/jp282475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Affiliation(s)
- Soolim Jeong
- Neurovascular Physiology Laboratory, School of Kinesiology,
Auburn University, Auburn, AL, USA 36849
| | - Kamila U. Pollin
- War Related Illness and Injury Study Center, Veterans
Affairs Medical Center, Washington, DC, USA 20422
| | - Lyndsey E. DuBose
- Division of Geriatric Medicine, Department of Medicine,
University of Colorado Anschutz Medical Campus, Aurora, CO, USA 80045
| | - Kanokwan Bunsawat
- Department of Internal Medicine, Division of Geriatrics,
University of Utah, Salt Lake City, UT, USA 84132
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4
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Carter KJ, Ward AT, Kellawan JM, Eldridge MW, Al-Subu A, Walker BJ, Lee JW, Wieben O, Schrage WG. Nitric oxide synthase inhibition in healthy adults reduces regional and total cerebral macrovascular blood flow and microvascular perfusion. J Physiol 2021; 599:4973-4989. [PMID: 34587648 PMCID: PMC9009720 DOI: 10.1113/jp281975] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 09/28/2021] [Indexed: 11/08/2022] Open
Abstract
The importance of nitric oxide (NO) in regulating cerebral blood flow (CBF) remains unresolved, due in part to methodological approaches, which lack a comprehensive assessment of both global and regional effects. Importantly, NO synthase (NOS) expression and activity appear greater in some anterior brain regions, suggesting region-specific NOS influence on CBF. We hypothesized that NO contributes to basal CBF in healthy adults, in a regionally distinct pattern that predominates in the anterior circulation. Fourteen healthy adults (7 females; 24 ± 5 years) underwent two magnetic resonance imaging (MRI) study visits with saline (placebo) or the NOS inhibitor, L-NMMA, administered in a randomized, single-blind approach. 4D flow MRI quantified total and regional macrovascular CBF, whereas arterial spin labelling (ASL) MRI quantified total and regional microvascular perfusion. L-NMMA (or volume-matched saline) was infused intravenously for 5 min prior to imaging. L-NMMA reduced CBF (L-NMMA: 722 ± 100 vs. placebo: 771 ± 121 ml/min, P = 0.01) with similar relative reductions (5-7%) in anterior and posterior cerebral circulations, due in part to the reduced cross-sectional area of 9 of 11 large cerebral arteries. Global microvascular perfusion (ASL) was reduced by L-NMMA (L-NMMA: 42 ± 7 vs. placebo: 47 ± 8 ml/100g/min, P = 0.02), with 7-11% reductions in both hemispheres of the frontal, parietal and temporal lobes, and in the left occipital lobe. We conclude that NO contributes to macrovascular and microvascular regulation including larger artery resting diameter. Contrary to our hypothesis, the influence of NO on cerebral perfusion appears regionally uniform in healthy young adults. KEY POINTS: Cerebral blood flow (CBF) is vital for brain health, but the signals that are key to regulating CBF remain unclear. Nitric oxide (NO) is produced in the brain, but its importance in regulating CBF remains controversial since prior studies have not studied all regions of the brain simultaneously. Using modern MRI approaches, a drug that inhibits the enzymes that make NO (L-NMMA) reduced CBF by up to 11% in different brain regions. NO helps maintain proper CBF in healthy adults. These data will help us understand whether the reductions in CBF that occur during ageing or cardiovascular disease are related to shifts in NO signalling.
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Affiliation(s)
- Katrina J Carter
- Department of Kinesiology, University of Wisconsin, Madison, WI, USA
| | - Aaron T Ward
- Department of Kinesiology, University of Wisconsin, Madison, WI, USA
| | - J Mikhail Kellawan
- Department of Health and Exercise Science, University of Oklahoma, Norman, OK, USA
| | | | - Awni Al-Subu
- Department of Pediatrics, University of Wisconsin, Madison, WI, USA
| | - Benjamin J Walker
- Department of Anesthesiology, University of Wisconsin, Madison, WI, USA
| | - Jeffrey W Lee
- Department of Anesthesiology, University of Wisconsin, Madison, WI, USA
| | - Oliver Wieben
- Department of Medical Physics, University of Wisconsin, Madison, WI, USA
- Department of Radiology, University of Wisconsin, Madison, WI, USA
| | - William G Schrage
- Department of Kinesiology, University of Wisconsin, Madison, WI, USA
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5
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Rashid P, Singh D, Sanjayan GJ. An efficient and convenient route for the synthesis of thiophene-2-carboxamidines as potential inhibitors of nitric oxide synthase (NOS). Tetrahedron Lett 2019. [DOI: 10.1016/j.tetlet.2019.151254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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6
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Fan JL, Bourdillon N, Meyer P, Kayser B. Oral Nitrate Supplementation Differentially Modulates Cerebral Artery Blood Velocity and Prefrontal Tissue Oxygenation During 15 km Time-Trial Cycling in Normoxia but Not in Hypoxia. Front Physiol 2018; 9:869. [PMID: 30061839 PMCID: PMC6054990 DOI: 10.3389/fphys.2018.00869] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/18/2018] [Indexed: 12/22/2022] Open
Abstract
Background: Nitrate is a precursor of nitric oxide (NO), an important regulator of cerebral perfusion in normoxic and hypoxic conditions. Nitrate supplementation could be used to improve cerebral perfusion and oxygenation during exercise in hypoxia. The effects of dietary nitrate supplementation on cerebral haemodynamics during exercise in severe hypoxia (arterial O2 saturation < 70%) have not been explored. Methods: In twelve trained male cyclists, we measured blood pressure (BP), middle cerebral artery blood velocity (MCAv), cerebrovascular resistance (CVR) and prefrontal oxyhaemoglobin and deoxyhaemoglobin concentration (O2Hb and HHb, respectively) during 15 km cycling time trials (TT) in normoxia and severe hypoxia (11% inspired O2, peripheral O2 saturation ∼66%) following 3-day oral supplementation with placebo or sodium nitrate (0.1 mmol/kg/day) in a randomised, double-blinded manner. We tested the hypothesis that dietary nitrate supplementation increases MCAv and cerebral O2Hb during TT in severe hypoxia. Results: During TT in normoxia, nitrate supplementation lowered MCAv by ∼2.3 cm/s and increased cerebral O2Hb by ∼6.8 μM and HHb by ∼2.1 μM compared to normoxia placebo (p ≤ 0.01 for all), while BP tended to be lowered (p = 0.06). During TT in severe hypoxia, nitrate supplementation elevated MCAv (by ∼2.5 cm/s) and BP (by ∼5 mmHg) compared to hypoxia placebo (p < 0.01 for both), while it had no effect on cerebral O2Hb (p = 0.98), HHb (p = 0.07) or PETCO2 (p = 0.12). Dietary nitrate had no effect of CVR during TT in normoxia or hypoxia (p = 0.19). Conclusion: Our findings indicate that during normoxic TT, the modulatory effect of dietary nitrate on regional and global cerebral perfusion is heterogeneous. Meanwhile, the lack of major changes in cerebral perfusion with dietary nitrate during hypoxic TT alludes to an exhausted cerebrovascular reserve.
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Affiliation(s)
- Jui-Lin Fan
- Wellington Medical Technology Group, Department of Surgery and Anaesthesia, University of Otago, Wellington, New Zealand.,Centre for Translational Physiology, University of Otago, Wellington, New Zealand
| | - Nicolas Bourdillon
- Institute of Sports Sciences, University of Lausanne, Lausanne, Switzerland
| | - Philippe Meyer
- Cardiology Service, Geneva University Hospital, Geneva, Switzerland
| | - Bengt Kayser
- Institute of Sports Sciences, University of Lausanne, Lausanne, Switzerland
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7
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Wilson JR, Brown NJ, Nian H, Yu C, Bidlingmaier M, Devin JK. Dipeptidyl Peptidase-4 Inhibition Potentiates Stimulated Growth Hormone Secretion and Vasodilation in Women. J Am Heart Assoc 2018; 7:e008000. [PMID: 29478970 PMCID: PMC5866333 DOI: 10.1161/jaha.117.008000] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 12/13/2017] [Indexed: 01/21/2023]
Abstract
BACKGROUND Diminished growth hormone (GH) is associated with impaired endothelial function and fibrinolysis. GH-releasing hormone is the primary stimulus for GH secretion and a substrate of dipeptidyl peptidase-4. We tested the hypothesis that dipeptidyl peptidase-4 inhibition with sitagliptin increases stimulated GH secretion, vasodilation, and tissue plasminogen activator (tPA) activity. METHODS AND RESULTS Healthy adults participated in a 2-part double-blind, randomized, placebo-controlled, crossover study. First, 39 patients (29 women) received sitagliptin or placebo on each of 2 days separated by a washout. One hour after study drug, blood was sampled and then arginine (30 g IV) was given to stimulate GH. Vasodilation was assessed by plethysmography and blood sampled for 150 minutes. Following a washout, 19 of the original 29 women received sitagliptin alone versus sitagliptin plus antagonist to delineate GH receptor (GHR)- (n=5), nitric oxide- (n=7), or glucagon-like peptide-1 receptor- (n=7) dependent effects. Sitagliptin enhanced stimulated GH secretion (P<0.01 versus placebo, for 30 minutes) and free insulin-like growth factor-1 (P<0.001 versus placebo, after adjustment for baseline) in women. Vasodilation and tPA increased in all patients, but sitagliptin enhanced vasodilation (P=0.01 versus placebo) and increased tPA (P<0.001) in women only. GHR blockade decreased free insulin-like growth factor-1 (P=0.04 versus sitagliptin alone) and increased stimulated GH (P<0.01), but decreased vascular resistance (P=0.01) such that nadir vascular resistance correlated inversely with GH (rs=-0.90, P<0.001). GHR blockade suppressed tPA. Neither nitric oxide nor glucagon-like peptide-1 receptor blockade affected vasodilation or tPA. CONCLUSIONS Sitagliptin enhances stimulated GH, vasodilation, and fibrinolysis in women. During sitagliptin, increases in free insulin-like growth factor-1 and tPA occur via the GHR, whereas vasodilation correlates with GH but occurs through a GHR-independent mechanism. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01701973.
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Affiliation(s)
- Jessica R Wilson
- Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN
| | - Nancy J Brown
- Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN
| | - Hui Nian
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | - Chang Yu
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | - Martin Bidlingmaier
- Endocrine Laboratory, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Jessica K Devin
- Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN
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8
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Montanari A, Lazzeroni D, Pelà G, Crocamo A, Lytvyn Y, Musiari L, Cabassi A, Cherney DZI. Calcium channel blockade blunts the renal effects of acute nitric oxide synthase inhibition in healthy humans. Am J Physiol Renal Physiol 2017; 312:F870-F878. [DOI: 10.1152/ajprenal.00568.2016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 02/01/2017] [Accepted: 02/06/2017] [Indexed: 01/25/2023] Open
Abstract
Our aim was to investigate whether blockade of calcium channels (CCs) or angiotensin II type 1 receptors (AT1R) modulates renal responses to nitric oxide synthesis inhibition (NOSI) in humans. Fourteen sodium-replete, healthy volunteers underwent 90-min infusions of 3.0 μg·kg−1·min−1 NG-nitro-l-arginine methyl ester (l-NAME) on 3 occasions, preceded by 3 days of either placebo (PL), 10 mg of manidipine (MANI), or 50 mg of losartan (LOS). At each phase, mean arterial pressure (MAP), glomerular filtration rate (GFR; inulin), renal blood flow (RBF; p-aminohippurate), urinary sodium (UNaV), and 8-isoprostane (U8-iso-PGF2αV; an oxidative stress marker) were measured. With PL + l -NAME, the following changes were observed: +6% MAP ( P < 0.005 vs. baseline), −10% GFR, −20% RBF, −49% UNaV ( P < 0.001), and +120% U8-iso-PGF2αV ( P < 0.01). In contrast, MAP did not increase during LOS + l-NAME or MANI + l-NAME ( P > 0.05 vs. baseline), whereas renal changes were the same during LOS + l-NAME vs. PL + l-NAME (ANOVA, P > 0.05). However, during MANI + l-NAME, changes vs. baseline in GFR (−6%), RBF (−12%), and UNaV (−34%) were blunted vs. PL + l-NAME and LOS + l-NAME ( P < 0.005), and the rise in U8-iso-PGF2αV was almost abolished (+37%, P > 0.05 vs. baseline; P < 0.01 vs. PL + l-NAME or LOS + l-NAME). We conclude that, since MANI blunted l-NAME-induced renal hemodynamic changes, CCs participate in the renal responses to NOSI in healthy, sodium-replete humans independent of changes in MAP and without the apparent contribution of the AT1R. Because the rise in U8-iso-PGF2αV was essentially prevented during MANI + l-NAME, CC blockade may oppose the renal effects of NOSI in part by counteracting oxidative stress responses to acutely impaired renal NO bioavailability.
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Affiliation(s)
- Alberto Montanari
- Department of Clinical and Experimental Medicine, University of Parma Medical School, Parma, Italy
| | - Davide Lazzeroni
- Prevention and Rehabilitation Unit at the Don Gnocchi Foundation and Department of Clinical and Experimental Medicine, University of Parma Medical School, Parma, Italy; and
| | - Giovanna Pelà
- Department of Clinical and Experimental Medicine, University of Parma Medical School, Parma, Italy
| | - Antonio Crocamo
- Department of Clinical and Experimental Medicine, University of Parma Medical School, Parma, Italy
| | - Yuliya Lytvyn
- Division of Nephrology, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Luisa Musiari
- Department of Clinical and Experimental Medicine, University of Parma Medical School, Parma, Italy
| | - Aderville Cabassi
- Department of Clinical and Experimental Medicine, University of Parma Medical School, Parma, Italy
| | - David Z. I. Cherney
- Division of Nephrology, University Health Network, University of Toronto, Toronto, Ontario, Canada
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9
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Kang S, Li H, Tang W, Martásek P, Roman LJ, Poulos TL, Silverman RB. 2-Aminopyridines with a Truncated Side Chain To Improve Human Neuronal Nitric Oxide Synthase Inhibitory Potency and Selectivity. J Med Chem 2015; 58:5548-60. [PMID: 26120733 PMCID: PMC4514563 DOI: 10.1021/acs.jmedchem.5b00573] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have analyzed a recently obtained crystal structure of human neuronal nitric oxide synthase (nNOS) and then designed and synthesized several 2-aminopyridine derivatives containing a truncated side chain to avoid the hydrophobic pocket that differentiates human and rat nNOS in an attempt to explore alternative binding poses along the substrate access channel of human nNOS. Introduction of an N-methylethane-1,2-diamine side chain and conformational constraints such as benzonitrile and pyridine as the middle aromatic linker were sufficient to increase human and rat nNOS binding affinity and inducible and endothelial NOS selectivity. We found that 14b is a potent inhibitor; the binding modes with human and rat nNOS are unexpected, inducing side chain rotamer changes in Gln478 (rat) at the top of the active site. Compound 19c exhibits Ki values of 24 and 55 nM for rat and human nNOS, respectively, with 153-fold iNOS and 1040-fold eNOS selectivity. 19c has 18% oral bioavailability.
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Affiliation(s)
- Soosung Kang
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
- New Drug Development Center, DGMIF, 80 Cheombok-ro, Dae-gu, Korea
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, California 92697-3900, United States
| | - Wei Tang
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Pavel Martásek
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, Texas 78384-7760, United States
| | - Linda J. Roman
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, Texas 78384-7760, United States
| | - Thomas L. Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, California 92697-3900, United States
| | - Richard B. Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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10
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Annedi SC. Cell-permeable inhibitors of neuronal nitric oxide synthase open new prospects for the treatment of neurological disorders. J Med Chem 2015; 58:1064-6. [PMID: 25602734 DOI: 10.1021/acs.jmedchem.5b00057] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The disubstituted pyrimidines based SAR study by Silverman et al. ( J. Med. Chem. 2014 , DOI: 10.1021/jm501719e ) was focused on improving bioavailability and physicochemical properties of the designed inhibitors while retaining the potency for neural nitric oxide synthase (nNOS) and selectivity over the other two nitric oxide synthase (NOS) isoforms (endothelial NOS and inducible NOS). One of the new promising lead compounds, compound 7, displayed nanomolar potency for nNOS (Ki = 19 nM), good selectivity over endothelial (260-fold), and inducible (41-fold) NOS isoforms and also showed potential for oral bioavailability (good cell permeability with efflux ratio of 1.8) and broad safety profile with minimal off-target activities at 50 CNS based receptors. This remarkable achievement not only serves as a template for next generation selective NOS inhibitor design but also opens new prospects for the treatment of neurological disorders.
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Affiliation(s)
- Subhash C Annedi
- Vibrant Pharma Inc. , 45 Dalkeith Drive, Unit 14, Brantford, Ontario, N3P 1M1, Canada
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11
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Static autoregulation in humans: a review and reanalysis. Med Eng Phys 2014; 36:1487-95. [DOI: 10.1016/j.medengphy.2014.08.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/07/2014] [Accepted: 08/03/2014] [Indexed: 01/12/2023]
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12
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Víteček J, Lojek A, Valacchi G, Kubala L. Arginine-based inhibitors of nitric oxide synthase: therapeutic potential and challenges. Mediators Inflamm 2012; 2012:318087. [PMID: 22988346 PMCID: PMC3441039 DOI: 10.1155/2012/318087] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 05/30/2012] [Indexed: 12/24/2022] Open
Abstract
In the past three decades, nitric oxide has been well established as an important bioactive molecule implicated in regulation of cardiovascular, nervous, and immune systems. Therefore, it is not surprising that much effort has been made to find specific inhibitors of nitric oxide synthases (NOS), the enzymes responsible for production of nitric oxide. Among the many NOS inhibitors developed to date, inhibitors based on derivatives and analogues of arginine are of special interest, as this category includes a relatively high number of compounds with good potential for experimental as well as clinical application. Though this group of inhibitors covers early nonspecific compounds, modern drug design strategies such as biochemical screening and computer-aided drug design have provided NOS-isoform-specific inhibitors. With an emphasis on major advances in this field, a comprehensive list of inhibitors based on their structural characteristics is discussed in this paper. We provide a summary of their biochemical properties as well as their observed effects both in vitro and in vivo. Furthermore, we focus in particular on their pharmacology and use in recent clinical studies. The potential of newly designed specific NOS inhibitors developed by means of modern drug development strategies is highlighted.
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Affiliation(s)
- Jan Víteček
- International Clinical Research Center-Center of Biomolecular and Cell Engineering, St. Anne's University Hospital Brno, 656 91 Brno, Czech Republic
- Institute of Biophysics, Academy of Sciences of the Czech Republic, 612 65 Brno, Czech Republic
| | - Antonín Lojek
- Institute of Biophysics, Academy of Sciences of the Czech Republic, 612 65 Brno, Czech Republic
| | - Giuseppe Valacchi
- Department of Evolutionary Biology, University of Ferrara, 44100 Ferrara, Italy
- Department of Food and Nutrition, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Lukáš Kubala
- International Clinical Research Center-Center of Biomolecular and Cell Engineering, St. Anne's University Hospital Brno, 656 91 Brno, Czech Republic
- Institute of Biophysics, Academy of Sciences of the Czech Republic, 612 65 Brno, Czech Republic
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13
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Annedi SC, Maddaford SP, Ramnauth J, Renton P, Rybak T, Silverman S, Rakhit S, Mladenova G, Dove P, Andrews JS, Zhang D, Porreca F. Discovery of a potent, orally bioavailable and highly selective human neuronal nitric oxide synthase (nNOS) inhibitor, N-(1-(piperidin-4-yl)indolin-5-yl)thiophene-2-carboximidamide as a pre-clinical development candidate for the treatment of migraine. Eur J Med Chem 2012; 55:94-107. [PMID: 22840695 DOI: 10.1016/j.ejmech.2012.07.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 07/01/2012] [Accepted: 07/04/2012] [Indexed: 10/28/2022]
Abstract
We recently reported a series of 1,6-disubstituted indoline-based thiophene amidine compounds (5) as selective neuronal nitric oxide synthase (nNOS) inhibitors to mitigate the cardiovascular liabilities associated with hERG K(+) channel inhibition (IC(50) = 4.7 μM) with previously reported tetrahydroquinoline-based selective nNOS inhibitors (4). The extended structure-activity relationship studies within the indoline core led to the identification of 43 as a selection candidate for further evaluations. The in vivo activity in two different pain (spinal nerve ligation and migraine pain) models, the excellent physicochemical and pharmacokinetic properties, oral bioavailability (F(po) = 91%), and the in vitro safety profile disclosed in this report make 43 an ideal candidate for further evaluation in clinical applications related to migraine pain.
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Affiliation(s)
- Subhash C Annedi
- NeurAxon Inc., 2395 Speakman Drive, Suite #1001, Mississauga, ON, Canada L5K 1B3.
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14
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Mladenova G, Annedi SC, Ramnauth J, Maddaford SP, Rakhit S, Andrews JS, Zhang D, Porreca F. First-in-class, dual-action, 3,5-disubstituted indole derivatives having human nitric oxide synthase (nNOS) and norepinephrine reuptake inhibitory (NERI) activity for the treatment of neuropathic pain. J Med Chem 2012; 55:3488-501. [PMID: 22420844 DOI: 10.1021/jm300138g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A family of different 3,5-disubstituted indole derivatives having 6-membered rings were designed, synthesized, and demonstrated inhibition of human nitric oxide synthase (NOS) with norepinephrine reuptake inhibitory activity (NERI). The structure-activity relationship (SAR) within the cyclohexane ring showed the cis-isomers to be more potent for neuronal NOS and selective over endothelial NOS compared to their trans-counterparts. Compounds, such as cis-(+)-37, exhibited dual nNOS and NET inhibition (IC(50) of 0.56 and 1.0 μM, respectively) and excellent selectivity (88-fold and 12-fold) over eNOS and iNOS, respectively. The lead compound (cis-(+)-37) showed lack of any direct vasoconstriction or inhibition of ACh-mediated vasorelaxation in isolated human coronary arteries. Additionally, cis-(+)-37 was effective at reversing both allodynia and thermal hyperalgesia in a standard Chung (spinal nerve ligation) rat neuropathic pain model. Overall, the data suggest that cis-(+)-37 is a promising dual action development candidate having therapeutic potential for the treatment of neuropathic pain.
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Affiliation(s)
- Gabriela Mladenova
- NeurAxon Inc., 2395 Speakman Drive, Suite 1001, Mississauga, Ontario L5K 1B3, Canada.
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15
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Ramnauth J, Renton P, Dove P, Annedi SC, Speed J, Silverman S, Mladenova G, Maddaford SP, Zinghini S, Rakhit S, Andrews J, Lee DKH, Zhang D, Porreca F. 1,2,3,4-tetrahydroquinoline-based selective human neuronal nitric oxide synthase (nNOS) inhibitors: lead optimization studies resulting in the identification of N-(1-(2-(methylamino)ethyl)-1,2,3,4-tetrahydroquinolin-6-yl)thiophene-2-carboximidamide as a preclinical development candidate. J Med Chem 2012; 55:2882-93. [PMID: 22335555 DOI: 10.1021/jm3000449] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Numerous studies have shown that selective nNOS inhibitors could be therapeutic in many neurological disorders. Previously, we reported a series of 1,2,3,4-tetrahydroquinoline-based potent and selective nNOS inhibitors, highlighted by 1 ( J. Med. Chem. 2011 , 54 , 5562 - 5575 ). Despite showing activity in two rodent pain models, 1 suffered from low oral bioavailability (18%) and moderate hERG channel inhibition (IC(50) = 4.7 μM). To optimize the properties of 1, we synthesized a small focused library containing various alkylamino groups on the 1-position of the 1,2,3,4-tetrahydroquinoline scaffold. The compounds were triaged based on their activity in the NOS and hERG manual patch clamp assays and their calculated physicochemical parameters. From these studies, we identified 47 as a potent and selective nNOS inhibitor with improved oral bioavailability (60%) and no hERG channel inhibition (IC(50) > 30 μM). Furthermore, 47 was efficacious in the Chung model of neuropathic pain and has an excellent safety profile, making it a promising preclinical development candidate.
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Affiliation(s)
- Jailall Ramnauth
- NeurAxon Inc., 2395 Speakman Drive, Suite 1001, Mississauga, Ontario, L5K 1B3, Canada.
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16
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Annedi SC, Maddaford SP, Ramnauth J, Renton P, Speed J, Rakhit S, Andrews JS, Porreca F. 3,5-Disubstituted indole derivatives as selective human neuronal nitric oxide synthase (nNOS) inhibitors. Bioorg Med Chem Lett 2012; 22:1980-4. [PMID: 22318159 DOI: 10.1016/j.bmcl.2012.01.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 01/10/2012] [Accepted: 01/11/2012] [Indexed: 11/18/2022]
Abstract
A series of 3,5-disubstituted indole derivatives was designed, synthesized and evaluated as inhibitors of human nitric oxide synthase (NOS). Various guanidine isosteric groups were explored at the 5-position of the indole ring, while keeping the basic amine side chain such as N-methylpiperidine ring, fixed at the 3-position of the indole ring. Compounds having 2-thiophene amidine and 2-furanyl amidine groups (7, 8, 10 and 12) showed increased activity for human neuronal NOS and good selectivity over endothelial and inducible NOS isoforms. Compound 8 was shown to reverse (10mg/kg, ip) thermal hyperalgesia in the L(5)/L(6) spinal nerve ligation (neuropathic pain) model and was devoid of any significant drug-drug interaction potential due to cytochrome P450 inhibition or cardiovascular liabilities associated with the inhibition of endothelial NOS.
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Affiliation(s)
- Subhash C Annedi
- NeurAxon Inc., 2395 Speakman Drive, Suite #1001, Mississauga, ON, Canada L5K 1B3.
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17
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Annedi SC, Ramnauth J, Maddaford SP, Renton P, Rakhit S, Mladenova G, Dove P, Silverman S, Andrews JS, Felice MD, Porreca F. Discovery of cis-N-(1-(4-(methylamino)cyclohexyl)indolin-6-yl)thiophene-2-carboximidamide: a 1,6-disubstituted indoline derivative as a highly selective inhibitor of human neuronal nitric oxide synthase (nNOS) without any cardiovascular liabilities. J Med Chem 2012; 55:943-55. [PMID: 22175766 DOI: 10.1021/jm201564u] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A series of 1,6-disubstituted indoline derivatives were synthesized and evaluated as inhibitors of human nitric oxide synthase (NOS) designed to mitigate the cardiovascular liabilities associated with previously reported tetrahydroquinoline-based selective neuronal NOS inhibitors due to higher lipophilicity ( J. Med. Chem. 2011 , 54 , 5562 - 5575 ). This new series produced similar potency and selectivity among the NOS isoforms and was devoid of any cardiovascular liabilities associated with QT prolongation due to hERG activity or endothelial NOS mediated vasoconstriction effect. The SAR studies led to the identification of cis-45, which was shown to reverse thermal hyperalgesia in vivo in the spinal nerve ligation model of neuropathic pain with excellent safety profile (off-target activities at 80 CNS related receptors/ion channels/transporters). The results presented in this report make cis-45 as an ideal tool for evaluating the potential role of selective nNOS inhibitors in CNS related disorders where excess NO produced by nNOS is thought to play a crucial role.
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Affiliation(s)
- Subhash C Annedi
- NeurAxon Inc. , 2395 Speakman Drive, Suite 1001, Mississauga, Ontario L5K 1B3, Canada
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18
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Annedi SC, Maddaford SP, Mladenova G, Ramnauth J, Rakhit S, Andrews JS, Lee DKH, Zhang D, Porreca F, Bunton D, Christie L. Discovery of N-(3-(1-methyl-1,2,3,6-tetrahydropyridin-4-yl)-1H-indol-6-yl) thiophene-2-carboximidamide as a selective inhibitor of human neuronal nitric oxide synthase (nNOS) for the treatment of pain. J Med Chem 2011; 54:7408-16. [PMID: 21923116 DOI: 10.1021/jm201063u] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
3,6-Disubstituted indole derivatives were designed, synthesized, and evaluated as inhibitors of human nitric oxide synthase (NOS). Bulky amine containing substitution on the 3-position of the indole ring such as an azabicyclic system showed better selectivity over 5- and 6-membered cyclic amine substitutions. Compound (-)-19 showed the best selectivity for neuronal NOS over endothelial NOS (90-fold) and inducible NOS (309-fold) among the current series. Compounds 16 and (-)-19 were shown to be either inactive or very weak inhibitors of human cytochrome P450 enzymes, indicating a low potential for drug-drug interactions. Compound 16 was shown to reverse thermal hyperalgesia in vivo in the Chung model of neuropathic pain. Compound 16 was also devoid of any significant vasoconstrictive effect in human coronary arteries, associated with the inhibition of human eNOS. These results suggest that 16 may be a useful tool for evaluating the potential role of selective nNOS inhibitors in the treatment of pain such as migraine and CTTH.
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Affiliation(s)
- Subhash C Annedi
- NeurAxon Inc., 2395 Speakman Drive, Suite 1001, Mississauga, Ontario, L5K 1B3, Canada.
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19
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Ramnauth J, Speed J, Maddaford SP, Dove P, Annedi SC, Renton P, Rakhit S, Andrews J, Silverman S, Mladenova G, Zinghini S, Nair S, Catalano C, Lee DKH, De Felice M, Porreca F. Design, synthesis, and biological evaluation of 3,4-dihydroquinolin-2(1H)-one and 1,2,3,4-tetrahydroquinoline-based selective human neuronal nitric oxide synthase (nNOS) inhibitors. J Med Chem 2011; 54:5562-75. [PMID: 21699209 PMCID: PMC5699206 DOI: 10.1021/jm200648s] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Neuronal nitric oxide synthase (nNOS) inhibitors are effective in preclinical models of many neurological disorders. In this study, two related series of compounds, 3,4-dihydroquinolin-2(1H)-one and 1,2,3,4-tetrahydroquinoline, containing a 6-substituted thiophene amidine group were synthesized and evaluated as inhibitors of human nitric oxide synthase (NOS). A structure-activity relationship (SAR) study led to the identification of a number of potent and selective nNOS inhibitors. Furthermore, a few representative compounds were shown to possess druglike properties, features that are often difficult to achieve when designing nNOS inhibitors. Compound (S)-35, with excellent potency and selectivity for nNOS, was shown to fully reverse thermal hyperalgesia when given to rats at a dose of 30 mg/kg intraperitonieally (ip) in the L5/L6 spinal nerve ligation model of neuropathic pain (Chung model). In addition, this compound reduced tactile hyperesthesia (allodynia) after oral administration (30 mg/kg) in a rat model of dural inflammation relevant to migraine pain.
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20
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Potential mechanisms of prospective antimigraine drugs: A focus on vascular (side) effects. Pharmacol Ther 2011; 129:332-51. [DOI: 10.1016/j.pharmthera.2010.12.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 11/09/2010] [Indexed: 12/13/2022]
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21
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Damkjær M, Vafaee M, Møller ML, Braad PE, Petersen H, Høilund-Carlsen PF, Bie P. Renal cortical and medullary blood flow responses to altered NO availability in humans. Am J Physiol Regul Integr Comp Physiol 2010; 299:R1449-55. [PMID: 20881099 DOI: 10.1152/ajpregu.00440.2010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The objective of this study was to quantify regional renal blood flow in humans. In nine young volunteers on a controlled diet, the lower abdomen was CT-scanned, and regional renal blood flow was determined by positron emission tomography (PET) scanning using H(2)(15)O as tracer. Measurements were performed at baseline, during constant intravenous infusion of nitric oxide (NO) donor glyceryl nitrate and after intravenous injection of NO synthase inhibitor N(ω)-monomethyl-L-arginine (L-NMMA). Using the CT image, the kidney pole areas were delineated as volumes of interest (VOI). In the data analysis, tissue layers with a thickness of one voxel were eliminated stepwise from the external surface of the VOI (voxel peeling), and the blood flow subsequently was determined in each new, reduced VOI. Blood flow in the shrinking VOIs decreased as the number of cycles of voxel peeling increased. After 4-5 cycles, blood flow was not reduced further by additional voxel peeling. This volume-insensitive flow was measured to be 2.30 ± 0.17 ml·g tissue(-1)·min(-1) during the control period; it increased during infusion of glyceryl nitrate to 2.97 ± 0.18 ml·g tissue(-1)·min(-1) (P < 0.05) and decreased after L-NMMA injection to 1.57 ± 0.17 ml·g tissue(-1)·min(-1) (P < 0.05). Cortical blood flow was 4.67 ± 0.31 ml·g tissue(-1)·min(-1) during control, unchanged by glyceryl nitrate, and decreased after L-NMMA [3.48 ± 0.23 ml·(g·min)(-1), P < 0.05]. PET/CT scanning allows identification of a renal medullary region in which the measured blood flow is 1) low, 2) independent of reduction in the VOI, and 3) reactive to changes in systemic NO supply. The technique seems to provide indices of renal medullary blood flow in humans.
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Affiliation(s)
- Mads Damkjær
- Institute of Molecular Medicine, Univ. of Southern Denmark, 21 J. B. Winsloews Vej, DK-5000 Odense, Denmark
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22
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Abstract
Acute treatment of migraine has benefited first from major advances in pharmacological science followed in short order, sometimes preceded, by an improved understanding of pathogenesis, especially of headache. This chapter reviews the mechanisms of migraine that provide an understanding of the pharmacology and therapeutic targets for acute migraine medications. General clinical approaches to acute therapy are reviewed, and indices of acceptable acute therapeutic outcomes are discussed. Currently the serotonin (5-HT) 1B/1D agonist group of drugs, triptans, forms the mainstay of acute therapeutic regimens. Other approaches to acute treatment such as simple analgesics, non-steroidal anti-inflammatory drugs (NSAIDs), ergots, and combination medications are reviewed. Finally, the newest acute treatments that are currently exploratory or under clinical investigation are discussed.
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Affiliation(s)
- J L Brandes
- Department of Neurology, Vanderbilt University Medical Center, Nashville Neuroscience Group, St Thomas Health Services, Department of Neurology, Vanderbilt University School of Medicine, Nashville, Tennessee 37203, USA.
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Boutouyrie P, Corvisier R, Ong KT, Vulser C, Lassalle C, Azizi M, Laloux B, Laurent S. Acute and chronic effects of acupuncture on radial artery: A randomized double blind study in migraine. Artery Res 2010. [DOI: 10.1016/j.artres.2009.12.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Kaluski E, Uriel N, Milo-Cotter O, Klapholz M. Nitric oxide synthase inhibitors in cardiogenic shock: present and future. Future Cardiol 2009; 4:183-9. [PMID: 19804295 DOI: 10.2217/14796678.4.2.183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cardiogenic shock (CS) accompanying myocardial infarction carries a case fatality rate of 40-50%. Profound myocardial dysfunction is partially reversible, and possibly related to a state of inflammatory storm accompanied by nitric oxide (NO) overproduction. CS survivors enjoy satisfactory longevity and quality of life. The focus of this review is to describe the available data regarding NO synthase (NOS) inhibitors in CS. In view of supportive evidence from mammalian research (inducible-NOS-knockout mice are less susceptible to ischemic and reperfusion injury), therapies mitigating NO overproduction were tested in human CS subjects. Human randomized clinical trials project excellent safety but lack of efficacy. Although the Phase III, multicenter, prospective, randomized, double-blind, placebo-controlled Study to Assess the Safety and Efficacy of Tilarginine Acetate (L-N(G)-monomethyl arginine citrate [L-NMMA]) in CS (TRIUMPH) trial demonstrated lack of clinical benefit of 5-h infusion of L-NMMA in CS, major design issues regarding the optimal timing, dosing, duration and NOS inhibitor need to be addressed prior to rendering this therapy ineffective.
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Affiliation(s)
- Edo Kaluski
- Director of Cardiac Catheterization Laboratories University Hospital and the University of Medicine & Dentistry, Department of Cardiology, 185 South Orange Ave, MSB I-538 Newark, NJ 07101, USA.
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25
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Short-term hypoxia reduces arterial stiffness in healthy men. Eur J Appl Physiol 2008; 105:19-25. [PMID: 18815804 DOI: 10.1007/s00421-008-0868-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2008] [Indexed: 02/04/2023]
Abstract
This study examined the effects of hypoxia (80% arterial oxyhaemoglobin saturation for 20 min) and the accompanying changes in heart rate and blood pressure on two components of arterial stiffness in healthy men. Augmentation index (AIx) and time to reflection (Tr) representing measures of muscular artery and aortic stiffness, respectively, were continuously measured. At first, subjects were exposed to either hypoxia (n = 12) or room air (n = 5). During early hypoxia AIx increased by 6% before decreasing to baseline. After hypoxia AIx decreased by a further 6%. In contrast there was no change in Tr. Six subjects were then exposed to hypoxia following infusion with the nitric oxide (NO) synthase inhibitor NG-mono-methyl-L: -arginine (L-NMMA) or saline. During hypoxia AIx decreased by 12% following saline but increased by 14% after L-NMMA and Tr did not change. These findings suggest that hypoxia may induce NO-mediated vasodilatation of small muscular arteries but not the aorta.
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26
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van Lieshout JJ, Secher NH. Point:Counterpoint: Sympathetic activity does/does not influence cerebral blood flow. Point: Sympathetic activity does influence cerebral blood flow. J Appl Physiol (1985) 2008; 105:1364-6. [PMID: 18583376 DOI: 10.1152/japplphysiol.90597.2008] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Johannes J van Lieshout
- Department of Internal Medicine, Medium Care Unit, AMC Center for Heart Failure Research, Academic Medical Center, University of Amerstdam, The Netherlands.
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27
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Gupta S, Mehrotra S, Villalón CM, Perusquía M, Saxena PR, MaassenVanDenBrink A. Potential role of female sex hormones in the pathophysiology of migraine. Pharmacol Ther 2007; 113:321-40. [PMID: 17069890 DOI: 10.1016/j.pharmthera.2006.08.009] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Accepted: 08/25/2006] [Indexed: 12/20/2022]
Abstract
Clinical evidence indicates that female sex steroids may contribute to the high prevalence of migraine in women, as well as changes in the frequency or severity of migraine attacks that are in tandem with various reproductive milestones in women's life. While female sex steroids do not seem to be involved in the pathogenesis of migraine per se, they may modulate several mediators and/or receptor systems via both genomic and non-genomic mechanisms; these actions may be perpetuated at the central nervous system, as well as at the peripheral (neuro)vascular level. For example, female sex steroids have been shown to enhance: (i) neuronal excitability by elevating Ca(2+) and decreasing Mg(2+) concentrations, an action that may occur with other mechanisms triggering migraine; (ii) the synthesis and release of nitric oxide (NO) and neuropeptides, such as calcitonin gene-related peptide CGRP, a mechanism that reinforces vasodilatation and activates trigeminal sensory afferents with a subsequent stimulation of pain centres; and (iii) the function of receptors mediating vasodilatation, while the responses of receptors inducing vasoconstriction are attenuated. The serotonergic, adrenergic and gamma-aminobutyric acid (GABA)-ergic systems are also modulated by sex steroids, albeit to a varying degree and with potentially contrasting effects on migraine outcome. Taken together, female sex steroids seem to be involved in an array of components implicated in migraine pathogenesis. Future studies will further delineate the extent and the clinical relevance of each of these mechanisms, and will thus expand the knowledge on the femininity of migraine.
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Affiliation(s)
- Saurabh Gupta
- Department of Pharmacology, Erasmus MC, University Medical Center Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands
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28
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Ramadan NM, Buchanan TM. New and future migraine therapy. Pharmacol Ther 2006; 112:199-212. [PMID: 16797716 DOI: 10.1016/j.pharmthera.2005.04.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2005] [Accepted: 04/10/2005] [Indexed: 12/21/2022]
Abstract
Modern neuroscience advanced our understanding of putative migraine mechanisms, which led to improved therapeutics. Indeed, mechanism-based acute migraine therapy gained steam in the early 1990s after the introduction of the triptans (5-HT1B,D agonists). Post-triptans, novel targets such as calcitonin gene-related peptide (CGRP) antagonists, inhibitors of excitatory glutamatergic receptors, and nitric oxide synthase (NOS) inhibitors are leading the pack in this exploding field of discovery research. In contrast, novel therapeutic targets for migraine prevention are lacking despite a hugely unmet need. To date, migraine prophylactic drugs are advanced based on expanded indications for already approved pharmaceuticals (e.g., topiramate, valproate, propranolol, and timolol). An improved understanding of the predisposition to an attack, genomic discoveries, valid and reliable biomarkers and surrogates, and predictive preclinical models likely will unravel the neuronal substrates for central hyperexcitability and nociceptive dysmodulation, hopefully leading us to better mechanism-based targets for prevention, and ultimately yielding drugs with optimal therapeutic ratios or indices.
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Affiliation(s)
- Nabih M Ramadan
- Department of Neurology, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA.
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29
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Knipp M. How to Control NO Production in Cells: Nω,Nω-Dimethyl-L-Arginine Dimethylaminohydrolase as a Novel Drug Target. Chembiochem 2006; 7:879-89. [PMID: 16680784 DOI: 10.1002/cbic.200500527] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Markus Knipp
- Department of Chemistry, University of Arizona, 1306 East University Boulevard, Tucson, AZ 85721-0041, USA.
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30
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31
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Michelson G, Wärntges S, Harazny J, Oehmer S, Delles C, Schmieder RE. EFFECT OF NOS INHIBITION ON RETINAL ARTERIAL AND CAPILLARY CIRCULATION IN EARLY ARTERIAL HYPERTENSION. Retina 2006; 26:437-44. [PMID: 16603964 DOI: 10.1097/01.iae.0000238550.74626.e5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Arterial hypertension is involved in the pathogenesis of end organ damage by influencing the ability of the vascular endothelium to produce nitric oxide (NO). This study analyzes changes of retinal and systemic NO-dependent circulation parameters by inhibiting nitric oxide synthase (NOS) in both hypertensive and normotensive individuals. METHODS In a double-blind crossover trial, 19 hypertensive patients (H, age 28.2 +/- 0.9 years) and 19 normotensive controls (N, age 26.9 +/- 0.9 years) were randomized treated either with candesartan or placebo. Both retinal capillary flow (RCF) and mean blood flow velocity of the central retinal artery (VCRA) were registered before and after NOS inhibition with N-monomethyl-L-arginine (L-NMMA, 3 mg/kg). In a subpopulation mean arterial pressure (MAP), cardiac output (CO), and the total peripheral resistance (TPR) were determined simultaneously. RESULTS Changes from baseline: In normotensive and hypertensive subjects infusion of L-NMMA led to an increase of MAP (N, +13.3 +/- 1.8%, P < 0.01; H, +14.3 +/- 2.4%, P < 0.01) and TPR (N, +36.9 +/- 3.8%, P < 0.01; H, +45.0 +/- 4.5%, P < 0.01), and to a decrease of CO (N, -21.1 +/- 1.5%, P < 0.01; H, -24.6 +/- 2.3%, P < 0.01). The L-NMMA effect on VCRA and RCF differed between controls and hypertensives. VCRA changed by + 17.3 +/- 6.2% (P < 0.05) and RCF by -7.3 +/- 3.0% (P < 0.05) in controls. In hypertensive subjects corresponding results were + 9.5 +/- 5.2% (P = NS) and + 2.7 +/- 3.8% (P = NS), respectively. The decrease of RCF due to L-NMMA was reduced in hypertension as compared to controls (P < 0.05). The calculated cross-sectional area of CRA was reduced by -58.7% in controls and increased by + 31.1% in hypertensive subjects. There was no significant correlation between the flow in the systemic and retinal circulation. CONCLUSION Only normotensives L-NMMA induces an acceleration of VCRA due to a probable vasoconstriction of the central retinal artery and despite of a reduced RCF. Already in early hypertension the NOS-dependent vascular tone in retinal arteries and capillaries is impaired. The regulation of the retinal capillary flow appeared to be independent from systemic circulation.
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Affiliation(s)
- Georg Michelson
- Augenklinik mit Poliklinik, Universität Erlangen-Nürnberg, Schwabachanlage 6, D-91053 Erlangen, Germany.
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32
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Striessnig J. Pathophysiology of migraine headache: Insight from pharmacology and genetics. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.ddmec.2005.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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33
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Lassen LH, Sperling B, Andersen AR, Olesen J. The effect of i.v. L-NG methylarginine hydrochloride (L-NMMA: 546C88) on basal and acetazolamide (Diamox) induced changes of blood velocity in cerebral arteries and regional cerebral blood flow in man. Cephalalgia 2005; 25:344-52. [PMID: 15839849 DOI: 10.1111/j.1468-2982.2004.00862.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The aim of this study was to estimate the effect of Nitric Oxide synthase (NOS)-inhibition (L-NMMA) on the diameter of the middle cerebral artery (MCA) and on regional cerebral blood flow (rCBF). Furthermore, to assess the effect of L-NMMA on acetazolamide induced increases in MCA blood velocity (Vmean) and rCBF. In an open crossover design 12 healthy subjects attended the laboratory twice. The first day 6 mg/kg L-LNMMA i.v. over 15 min preceded 1 g acetazolamide i.v. over 5 min. Eight days later only acetazolamide was given. V(mean) in MCA was determined with transcranial Doppler (TCD) and rCBF with Xe-133 inhalation SPECT at baseline, after L-NMMA and 25 and 55 min after acetazolamide infusion. After L-NMMA the decrease in rCBF(MCA) was 6.8% (+/- 7.4) (P < 0.019, n = 12), whereas V(mean) was not affected (P = 0.83, n = 8). The change in MCA diameter was estimated to - 1.3% (P = 0.44, n = 8). L-NMMA did not affect acetazolamide increases in Vmean (P = 0.67, n = 8) nor rCBF (P = 0.29, n = 12). The percentage increase of V(mean) was 1.5 times that of rCBF (n = 8). Our data suggest that the basal tone of human cerebral arterioles but not of conduit arteries is NO-dependent. The action of acetazolamide in man is not NO-dependent.
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Affiliation(s)
- L h Lassen
- Department of Neurology, Glostrup Hospital, University of Copenhagen, Glostrup, Denmark.
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