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Ueda, Masaya Takumida, Sachio Taken T. Functional Role of Nitric Oxide in the Nasal Mucosa of the Guinea Pig after Instillation with Lipopolysaccharide. Acta Otolaryngol 2009. [DOI: 10.1080/00016480118110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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2
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Willenborg DO, Staykova M, Fordham S, O'Brien N, Linares D. The contribution of nitric oxide and interferon gamma to the regulation of the neuro-inflammation in experimental autoimmune encephalomyelitis. J Neuroimmunol 2007; 191:16-25. [PMID: 17904645 DOI: 10.1016/j.jneuroim.2007.09.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Accepted: 09/07/2007] [Indexed: 01/22/2023]
Abstract
Nitric oxide (NO) is a key messenger involved in physiological functions including endothelium-dependent vascular relaxation, inhibition of platelet adhesion and aggregation and regulation of inflammatory and immune responses. Here we briefly introduce NO and its functions and then describe our work over the past several years examining the role of NO in EAE in both the rat and the mouse. We show that NO plays a significant role in determining the resistance or susceptibility to EAE in various strains and or sexes of animals. We demonstrate that NO down-regulates several aspects of CNS inflammation but also has a dual role in that it is required for inflammation in some situations.
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Affiliation(s)
- David O Willenborg
- Neurosciences Research Unit, Australian National University Medical School, The Canberra Hospital, ACT 2606, Australia.
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3
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Leong SK, Ruan RS, Zhang Z. A critical assessment of the neurodestructive and neuroprotective effects of nitric oxide. Ann N Y Acad Sci 2002; 962:161-81. [PMID: 12076973 DOI: 10.1111/j.1749-6632.2002.tb04066.x] [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: 11/28/2022]
Abstract
Whether nitric oxide is cytodestructive or cytoprotective is of obvious clinical importance. The debate on this subject in the past decade has generated much "heat and light". This paper focuses on the actions of NO on the nervous system and reexamines the controversial issue and the contribution of the authors and their colleagues in the light of recent findings. We also report new findings, critically assesses previous experimental data, and share perspectives on this important subject.
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Affiliation(s)
- Seng-Kee Leong
- Department of Anatomy, National University of Singapore, Singapore.
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4
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Zhelyaskov VR, Godwin DW. Photolytic generation of nitric oxide through a porous glass partitioning membrane. Nitric Oxide 1999; 2:454-9. [PMID: 10342488 DOI: 10.1006/niox.1998.0195] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We report a new method of generating nitric oxide that possesses several potential advantages for experimental use. This method consists of a microphotolysis chamber where NO is released by illuminating photolabile NO donors with light from a xenon lamp. NO then diffuses through a porous glass membrane to the experimental preparation. We observed that the rate of NO generation is a linear function of light intensity. Due to a dynamic equilibrium between the mechanisms of NO generation and dissipation (by diffusion or oxidation) the NO concentration in the experimental cuvette can be reversibly and reproducibly controlled. The major potential advantages of this device include its use as a NO point source, and the ability to partition the NO donor compound from the experimental preparation by a porous glass membrane. The diffusion of the caging moiety through the membrane is insignificant as seen by absorption spectroscopy due to its large relative size to NO. In this way, the porous glass membrane protects the preparation from the potential bioactive effects of the caging moiety, which is an important consideration for biological experiments.
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Affiliation(s)
- V R Zhelyaskov
- World Precision Instruments, Inc., International Trade Center, Sarasota, Florida 34240-9258, USA.
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5
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Nishio E, Watanabe Y. No induced apoptosis accompanying the change of oncoprotein expression and the activation of CPP32 protease. Life Sci 1998; 62:239-45. [PMID: 9488102 DOI: 10.1016/s0024-3205(97)01092-8] [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: 02/06/2023]
Abstract
Previously we have shown that nitric oxide (NO) donors induced apoptosis in vascular smooth muscle cells (VSMCs). However, the mechanisms by which NO induced apoptosis in VSMCs are entirely unknown. In the present study, we intended to identify the mechanism by which NO donors induce apoptosis in VSMCs. First, we evaluated the expression of c-Myc, P53, and Bcl-2 proteins in VSMCs treated by NO donors. c-Myc and P53 protein expression increased after VSMCs were incubated with NO donors for 6 hr and reached a maximum level at 24 hr, while Bcl-2 protein decreased after 12 hr incubation. Next we investigated to see whether the CPP32 protease activation was involved in NO donors-induced apoptosis. In VSMCs treated by NO donors, the increase of CPP32 protease activity was observed and specific inhibition of CPP32 activity significantly prevented apoptosis induced by NO donors in a dose-dependent manner. These results suggest that NO donors induced apoptosis through proto-oncoprotein expression and CPP32-like protease activation.
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Affiliation(s)
- E Nishio
- Department of Pharmacology, National Defense Medical College, Tokorozawa, Saitama, Japan
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6
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Zhelyaskov VR, Gee KR, Godwin DW. Control of NO Concentration in Solutions of Nitrosothiol Compounds by Light. Photochem Photobiol 1998. [DOI: 10.1111/j.1751-1097.1998.tb05200.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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7
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Liang JF, Akaike T. Inhibition of lipopolysaccharide and cytokine mixture-mediated hepatocyte nitric oxide synthesis by dimethyl sulfoxide. Biochem Biophys Res Commun 1997; 239:517-21. [PMID: 9344862 DOI: 10.1006/bbrc.1997.7506] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Treatment and pretreatment of hepatocytes with 2% dimethyl sulfoxide (DMSO) inhibited lipopolysaccharide and cytokine mixture (LPS/CM)-mediated NO synthesis in hepatocytes without any obvious effects on cell viability. DMSO at concentrations of 0.5-4% stimulated DNA replication and increased albumin secretion in LPS/CM-treated hepatocytes. Genisein, a inhibitor of protein tyrosine kinase (PTK), inhibited LPS/CM-mediated NO synthesis in hepatocytes. These results suggest that PTK is critical for hepatocyte NO synthesis, and DMSO-inhibited NO synthesis may be associated with prevention of LPS/CM-induced PTK activation in hepatocytes.
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Affiliation(s)
- J F Liang
- Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing, People's Republic of China
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8
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Lev-Ram V, Nebyelul Z, Ellisman MH, Huang PL, Tsien RY. Absence of cerebellar long-term depression in mice lacking neuronal nitric oxide synthase. Learn Mem 1997; 4:169-77. [PMID: 10456061 DOI: 10.1101/lm.4.1.169] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Extensive pharmacological evidence suggests that nitric oxide (NO) is a crucial transmitter for cerebellar long-term depression (LTD), a long-lasting decrease in efficacy of the synapses from parallel fibers onto Purkinje neurons, triggered by coincident presynaptic activity and postsynaptic depolarization. We now show that LTD cannot be induced in Purkinje neurons under whole-cell patch clamp in cerebellar slices from young adult mice genetically lacking neuronal nitric oxide synthase (nNOS). This genetic evidence confirms the essentiality of NO and nNOS for LTD in young adult rodents. Surprisingly, LTD in cells from nNOS knockout mice cannot be rescued by photolytic uncaging of NO and cGMP inside Purkinje neurons, although such stimuli circumvent acute pharmacological inhibition of nNOS and soluble guanylate cyclase in normal rodents. Also slices from knockout mice show no deficit in cGMP elevation in response to exogenous NO. Therefore, prolonged absence of nNOS allows atrophy of the signaling pathway downstream of cGMP.
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Affiliation(s)
- V Lev-Ram
- Department of Pharmacology, University of California San Diego, La Jolla 92093-0647, USA
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9
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Godwin DW, Che D, O'Malley DM, Zhou Q. Photostimulation with caged neurotransmitters using fiber optic lightguides. J Neurosci Methods 1997; 73:91-106. [PMID: 9130682 DOI: 10.1016/s0165-0270(96)02208-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
'Caged' neurotransmitters are molecules that are transformed to a neuroactive state by exposure to light of an appropriate wavelength and intensity. Use of these substances has centered on in vitro bath application and subsequent activation using light from lasers or flashlamps that is delivered into the preparation through microscope optics. We have tested a new and simpler method, using finely tapered fiberoptic lightguides, that promises to expand the use of caged compounds for in vitro and in vivo experimentation. We demonstrated the feasibility and flexibility of this method for caged neurotransmitter delivery using a range of ex vitro, in vitro and in vivo approaches. The degree and timing of uncaging could be controlled by manipulating the wavelength, intensity and timing of the light projected into the optical fiber. Because of the small size of the light guide and the ability to control light exposure at the source, this new method promises greater control over the spatial and temporal delivery of neuroactive substances than simple bath or iontophoretic application, and enables delivery of conventional neurotransmitters with a spatial and temporal resolution closer to that of the natural neuronal circuitry. In addition, this new method allows the application of normally labile substances, such as the free radical gas nitric oxide, by the photoconversion of photosensitive precursors.
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Affiliation(s)
- D W Godwin
- Department of Neurobiology and Behavior, State University of New York at Stony Brook, New York 11794-5230, USA.
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10
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Dietz NM, Joyner MJ, Shepherd JT. Vasovagal syncope and skeletal muscle vasodilatation: the continuing conundrum. Pacing Clin Electrophysiol 1997; 20:775-80. [PMID: 9080509 DOI: 10.1111/j.1540-8159.1997.tb03903.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
During vasovagal syncope, profound bradycardia and hypotension occur. Atropine administration can prevent the bradycardia but not the hypotension, suggesting that marked peripheral vasodilation is a major cause of the fall in arterial pressure. This concept has been confirmed since vasovagal syncope can be seen in patients who have undergone heart transplantation and also in patients subject to cardiac pacing. In both cases, there is no bradycardia but hypotension during the syncopal attacks. The major site of the vasodilation is in skeletal muscle and muscle sympathetic nerve activity is suppressed just prior to and during vasovagal attacks, indicating that sympathetic withdrawal contributes to the dilation. However, the skeletal muscle vasodilation seen during syncope is greater than that caused by sympathetic withdrawal alone, and it is absent in limbs that have undergone surgical sympathectomy, or local anesthetic nerve block. These observations suggest a role for neurally mediated "active" vasodilation during syncope. The afferent neural pathways that evoke the profound vasodilation during vasovagal attacks remain the subject of debate. The neural pathways responsible for the active component of the dilation are also unknown. Recent evidence has demonstrated that cholinergic, beta-adrenergic, and nitroxidergic (nitric oxide) vasodilator mechanisms are not essential to observe the dilation, demonstrating that the mechanisms responsible for it remain a continuing conundrum.
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Affiliation(s)
- N M Dietz
- Mayo Foundation, Rochester, Minnesota, USA
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11
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Eri?ir A, Van Horn SC, Bickford ME, Sherman SM. Immunocytochemistry and distribution of parabrachial terminals in the lateral geniculate nucleus of the cat: A comparison with corticogeniculate terminals. J Comp Neurol 1997. [DOI: 10.1002/(sici)1096-9861(19970127)377:4<535::aid-cne5>3.0.co;2-3] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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Tymianski M, Tator CH. Normal and abnormal calcium homeostasis in neurons: a basis for the pathophysiology of traumatic and ischemic central nervous system injury. Neurosurgery 1996; 38:1176-95. [PMID: 8727150 DOI: 10.1097/00006123-199606000-00028] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Clinical recovery after central nervous system (CNS) trauma or ischemia may be limited by a neural injury process that is triggered and perpetuated at the cellular level, rather than by a lesion amenable to surgical repair. It is widely thought that one such process, a fundamental pathological mechanism initiated by CNS injury, is a disruption of cellular Ca2+ homeostasis. Because of the critical role of Ca2+ ions in regulating innumerable cellular functions, this major homeostatic disturbance is thought to trigger neuronal and axonal degeneration and produce clinical disability. We review those aspects of normal and pathological Ca2+ homeostasis in neurons that relate to neurodegeneration and to the application of neuroprotective strategies for the treatment of CNS injury. In particular, we examine the contribution of Ca(2+)-permeable ionic channels, Ca2+ pumps, intracellular Ca2+ stores, intracellular Ca2+ buffering systems, and the roles of secondary, Ca(2+)-dependent processes in neurodegeneration. A number of hypotheses linking Ca2+ ions and Ca2+ permeable channels to neurotoxicity are discussed with an emphasis on strategies for lessening Ca(2+)-related damage. A number of these strategies may have a future role in the treatment of traumatic and ischemic CNS injury.
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Affiliation(s)
- M Tymianski
- Division of Neurosurgery, Toronto Hospital, Ontario, Canada
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Tymianski M, Tator CH. Normal and Abnormal Calcium Homeostasis in Neurons: A Basis for the Pathophysiology of Traumatic and Ischemic Central Nervous System Injury. Neurosurgery 1996. [DOI: 10.1227/00006123-199606000-00028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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Kremser K, Stangl H, Pahan K, Singh I. Nitric oxide regulates peroxisomal enzyme activities. EUROPEAN JOURNAL OF CLINICAL CHEMISTRY AND CLINICAL BIOCHEMISTRY : JOURNAL OF THE FORUM OF EUROPEAN CLINICAL CHEMISTRY SOCIETIES 1995; 33:763-74. [PMID: 8620052 DOI: 10.1515/cclm.1995.33.11.763] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have previously shown that peroxisomes are involved in the production and detoxification of reactive oxygen species and that peroxisomal functions are damaged by such oxygen species. Since nitric oxide is not only a cellular messenger, but also a free radical, it would be interesting to detect a connection between nitric oxide levels and peroxisomal enzyme activities. To determine if nitric oxide has an effect on the activities of peroxisomal functions and whether this effect is based solely on its chemical properties as reactive oxygen species or its action as a second messenger, effectors of the cellular nitric oxide level were applied to a cell model (human skin fibroblasts in culture) or directly to the enzymatic assays or both. If applied to the monolayer at non-cytotoxic concentrations, N-nitro-L-arginine methyl ester hydrochloride, an inhibitor of nitric oxide synthase (EC 1.14.13.39), increased catalase (EC 1.11.1.6) activity by more than 10% and decreased the activity of the peroxisomal fatty acid oxidation system by more than 10%. The effect was concentration-dependent. L-Arginine had the contrary effect. Combinations of L-arginine and N-nitro-L-arginine methyl ester hydrochloride compensated one another. If applied directly to the assays, S-nitroso-N-acetylpenicillamine and sodium nitroprusside inhibited catalase activity in a concentration-dependent manner. Sodium nitro-prusside had no effect on the peroxisomal beta-oxidation system unless cells were pretreated with N-nitro-L-arginine methyl ester overnight (50% inhibition). The results show a differential effect for the application of nitric oxide-effectors on fibroblast monolayers, cell suspensions and under assay conditions. Depending on the conditions of the incubation, nitric oxide applied to the cell monolayer at low doses acts as a second messenger in cells rather than as reactive oxygen species. Under assay conditions the effect of nitric oxide is more likely that of a reactive oxygen species because it inhibits all measured enzyme activities.
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Affiliation(s)
- K Kremser
- Institut für Medizinische Chemie, Universität Wien, Austria
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15
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Egan JM, Henderson TE, Bernier M. Arginine enhances glycogen synthesis in response to insulin in 3T3-L1 adipocytes. THE AMERICAN JOURNAL OF PHYSIOLOGY 1995; 269:E61-6. [PMID: 7631779 DOI: 10.1152/ajpendo.1995.269.1.e61] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The present study was undertaken to define the role of L-arginine (L-Arg) in glucose metabolism in differentiated 3T3-L1 adipocytes in culture. L-Arg alone had no effect on 2-deoxyglucose uptake or basal glycogen synthesis, but this amino acid increased by 153 +/- 10% (P < 0.01) the incorporation of glucose into glycogen in insulin-treated cells. L-Glutamate (L-Glu), a major metabolite of L-Arg, also enhanced insulin-stimulated glycogen synthesis. The response to insulin was not altered by L-lysine (L-Lys), but the effect of L-Arg was markedly attenuated by L-Lys. Cell incubation with L-Arg markedly enhanced arginase-mediated urea synthesis, whereas L-Lys abolished this response. The stimulatory effect of L-Arg on insulin-stimulated glycogen synthesis did not appear to be accounted for by the generation of polyamines or the production of nitric oxide, both potentially derived from the enzymatic conversion of L-Arg. In the presence of insulin, cellular ATP levels were significantly increased by L-Arg, L-Glu, and L-Lys as well. These data suggest that metabolic degradation of L-Arg not related to citric acid cycle activity is important in the mechanism by which L-Arg enhances insulin-stimulated glycogen synthesis.
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Affiliation(s)
- J M Egan
- Diabetes Unit, National Institute on Aging, Baltimore, Maryland 21224, USA
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Shepherd JT. Interactions of neurotransmitters and endothelial cells in determining vascular tone. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1995; 381:1-13. [PMID: 8867818 DOI: 10.1007/978-1-4615-1895-2_1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- J T Shepherd
- Mayo Clinic and Mayo Foundation, Rochester, Minnesota, USA
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17
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Skinner JE. Low-dimensional chaos in biological systems. BIO/TECHNOLOGY (NATURE PUBLISHING COMPANY) 1994; 12:596-600. [PMID: 7764948 DOI: 10.1038/nbt0694-596] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
During the past five years general rules have been developed for the application of chaos theory to biology and medicine, which enable investigators to avoid the pitfalls that invalidated and trivialized many earlier results. The importance of biological chaos is that the variables governing the spatial and temporal geometries of the system may be few in number, fractional in dimension, and thus enable low-energy control with complex deterministic consequences. The complexity of control inherent in chaotic systems may be important in the dynamics of gene expression and translation. Extending these ideas may lead to completely novel ways to modulate protein production by introducing simple pulses at critical times or places.
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Affiliation(s)
- J E Skinner
- Totts Gap Medical Research Laboratories, Bangor, PA 18013
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18
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Devi L, Petanceska S, Liu R, Arbabha B, Bansinath M, Garg U. Regulation of neuropeptide-processing enzymes by nitric oxide in cultured astrocytes. J Neurochem 1994; 62:2387-93. [PMID: 8189243 DOI: 10.1046/j.1471-4159.1994.62062387.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Nitric oxide (NO), a recently discovered neurotransmitter, has been shown to have a cytostatic effect on cultured glia. A NO-generating agent, S-nitroso-N-acetyl-penicillamine (SNAP), was used to treat C6 glioma and primary cortical astrocytes. The levels of a monobasic peptide-processing enzyme activity and carboxypeptidase E activity were examined. The cellular levels of these two enzymes are specifically reduced in response to treatment with SNAP. A decrease of approximately 30-50% in these two enzyme activities was seen in both primary astrocytes and C6 glioma cells. This decrease in cellular enzyme activities is not due to increased secretion because the secreted activity is also reduced in response to SNAP treatment in both the glioma cells and the primary astrocytes. Removal of SNAP treatment causes the carboxypeptidase enzyme activity to return to control levels within 3 days. Northern and western blot analyses indicate that the reduced cellular level of carboxypeptidase E is not due to reduced expression of the messenger RNA or protein, suggesting that the SNAP treatment is affecting factors that influence carboxypeptidase E activity. Taken together, these results imply that NO is involved in the regulation of peptide biosynthetic enzymes and this could lead to the antimitogenic action of SNAP on glia.
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Affiliation(s)
- L Devi
- Department of Pharmacology, New York University Medical Center, NY 10016
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Sexton DJ, Muruganandam A, McKenney DJ, Mutus B. Visible light photochemical release of nitric oxide from S-nitrosoglutathione: potential photochemotherapeutic applications. Photochem Photobiol 1994; 59:463-7. [PMID: 8022889 DOI: 10.1111/j.1751-1097.1994.tb05065.x] [Citation(s) in RCA: 138] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Some aspects of the physiological role of NO may be mediated by stable NO-carriers such as S-nitrosoglutathione and related S-nitrosothiols. In this report we show that irradiation of S-nitrosoglutathione at either absorption band (lambda max = 340 nm or 545 nm) results in the release of nitric oxide. Photolysis of S-nitrosoglutathione at 545 nm exhibited a quantum yield of 0.056 +/- 0.002 and was best approximated by a first-order process with kobs = 4.9 x 10(-7) +/- 0.3 x 10(-7) s-1. The photolytic release of NO from S-nitrosoglutathione resulted in an enhanced cytotoxic effect of S-nitrosoglutathione on HL-60 leukemia cells. That the cytotoxic effect of S-nitrosoglutathione was diminished by the addition of oxyhemoglobin strongly suggests that NO is the cytotoxic species. The finding that NO can be readily liberated from S-nitrosoglutathione by visible radiation indicates that the photochemical properties of this compound in the visible spectrum must be considered in order to obtain meaningful data as to its physiological role and the S-nitrosoglutathione and related compounds may find use as photochemotherapeutic agents.
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Affiliation(s)
- D J Sexton
- Department of Chemistry and Biochemistry, University of Windsor, Ontario, Canada
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