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1.
J Cell Mol Med ; 23(5): 3357-3368, 2019 05.
Article in English | MEDLINE | ID: mdl-30770640

ABSTRACT

Ligustilide (LIG) is the main lipophilic component of the Umbelliferae family of pharmaceutical plants, including Radix angelicae sinensis and Ligusticum chuanxiong. LIG shows various pharmacological properties associated with anti-inflammation and anti-apoptosis in several kinds of cell lines. However, the therapeutic effects of LIG on chondrocyte apoptosis remain unknown. In this study, we investigated whether LIG had an anti-apoptotic activity in sodium nitroprusside (SNP)-stimulated chondrocyte apoptosis and could delay cartilage degeneration in a surgically induced rat OA model, and elucidated the potential mechanisms. In vitro studies revealed that LIG significantly suppressed chondrocyte apoptosis and cytoskeletal remodelling, which maintained the nuclear morphology and increased the mitochondrial membrane potential. In terms of SNP, LIG treatment considerably reduced the expression levels of cleaved caspase-3, Bax and inducible nitric oxide synthase and increased the expression level of Bcl-2 in a dose-dependent manner. The LIG-treated groups presented a significantly suppressed expression of activating transcription factor 2 and phosphorylation of Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). The inhibitory effect of LIG was enhanced by the p38 MAPK inhibitor SB203580 or the JNK inhibitor SP600125 and offset by the agonist anisomycin. In vivo studies demonstrated that LIG attenuated osteoarthritic cartilage destruction by inhibiting the cartilage chondrocyte apoptosis and suppressing the phosphorylation levels of activating transcription factor 2, JNK and p38 MAPK. This result was confirmed by histological analyses, micro-CT, TUNEL assay and immunohistochemical analyses. Collectively, our studies indicated that LIG protected chondrocytes against SNP-induced apoptosis and delayed articular cartilage degeneration by suppressing JNK and p38 MAPK pathways.


Subject(s)
4-Butyrolactone/analogs & derivatives , Apoptosis/drug effects , Cartilage, Articular/pathology , Chondrocytes/enzymology , Chondrocytes/pathology , JNK Mitogen-Activated Protein Kinases/metabolism , Nitric Oxide/toxicity , p38 Mitogen-Activated Protein Kinases/metabolism , 4-Butyrolactone/chemistry , 4-Butyrolactone/pharmacology , Animals , Cell Nucleus Shape/drug effects , Cell Survival/drug effects , Chondrocytes/drug effects , Disease Models, Animal , Enzyme Activation/drug effects , Injections, Intra-Articular , Male , Membrane Potential, Mitochondrial/drug effects , Nitroprusside/pharmacology , Osteoarthritis/pathology , Rats, Sprague-Dawley
2.
Drug Metab Lett ; 10(4): 254-263, 2017.
Article in English | MEDLINE | ID: mdl-27774888

ABSTRACT

BACKGROUND/AIMS: Genipin is a component of Japanese traditional herbal medicine (Kampo), inchinkoto, and is used for the treatment of various liver injuries. However, there are few scientific evidence for its anti-inflammatory effects and mechanisms. In inflamed liver, proinflammatory cytokines including tumor necrosis factor (TNF)-α and interleukin (IL)-1ß stimulate liver cells, followed by the expression of inducible nitric oxide synthase (iNOS). Excessive levels of NO produced by iNOS have been implicated as one of the factors in liver injury. Thus it is essential to inhibit iNOS induction for the prevention of liver injury. In this study, we examined IL-1ß-stimulated hepatocytes as a simple "in vitro liver injury model" to investigate liver protective effects of genipin. METHODS: Primary cultured rat hepatocytes were treated with IL-1ß in the presence or absence of genipin. The induction of NO production and iNOS, and its signaling pathway were analyzed. RESULTS: In IL-1ß-stimulated hepatocytes, genipin inhibited the production of NO dose- and timedependently, and reduced the levels of iNOS protein and its mRNA expression. Genipin also reduced mRNA expressions of TNF-α and IL-6. Genipin inhibited two essential signaling pathways for iNOS induction, IκB degradation/NF-κB activation and type I IL-1 receptor upregulation. Transfection experiments revealed that genipin decreased the expression of iNOS mRNA through both inhibitions of the promoter activation and mRNA stabilization. Delayed administration of genipin after IL-1ß addition also inhibited iNOS induction. CONCLUSION: Genipin influenced the induction of inflammatory mediators, iNOS and TNF-α, in part through the inhibition of NF-κB activation in hepatocytes. Genipin may have therapeutic potential for organ injuries including liver.


Subject(s)
Iridoids/pharmacology , Liver Failure, Acute/drug therapy , Liver/drug effects , NF-kappa B/metabolism , Nitric Oxide Synthase Type II/metabolism , Plant Extracts/pharmacology , Protective Agents/pharmacology , Animals , Cells, Cultured , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Hepatocytes , Humans , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Iridoids/therapeutic use , Liver/cytology , Liver/metabolism , Medicine, Kampo/methods , Nitric Oxide/toxicity , Plant Extracts/chemistry , Plant Extracts/therapeutic use , Primary Cell Culture , Protective Agents/therapeutic use , RNA, Messenger/metabolism , Rats , Rats, Wistar , Up-Regulation
3.
Life Sci ; 139: 69-74, 2015 Oct 15.
Article in English | MEDLINE | ID: mdl-26285175

ABSTRACT

AIMS: The present study has been designed to explore the molecular mechanism of chlorogenic acid (CGA) in the protective effect against glutamate-induced neuronal cell death. MAIN METHODS: Cortical neurons in primary culture were exposed to 300 µM l-glutamic acid or vehicle, with or without 10 µM CGA or 10 µM MK-801. After 16 h, primary cultures were stained with propidium iodide (PI)/Hoechst or calcein. Double-staining with PI and Hoechst was performed to confirm whether cell death induced by glutamate was apoptotic. In addition, intracellular concentrations of Ca(2+) were observed using Ca(2+) indicator fura-2. KEY FINDINGS: We investigated the protective effects of CGA on glutamate-induced neuronal cell death using primary cultures of mouse cerebral cortex because the release of glutamate during brain ischemia triggers death of neurons. Glutamate-induced neuronal cell death was inhibited by treatment with CGA. In addition, CGA prevented the increase in intracellular concentrations of Ca(2+) caused by the addition of glutamate to cultured neurons. On the other hand, there was little effect of CGA on cell death induced by nitric oxide, which is downstream of the ischemic neuronal cell death. Our results suggested that the polyphenol CGA in coffee protects neurons from glutamate neurotoxicity by regulating Ca(2+) entry into neurons. SIGNIFICANCE: CGA in coffee may have clinical benefits for neurodegenerative diseases such as ischemic stroke.


Subject(s)
Chlorogenic Acid/pharmacology , Coffee/chemistry , Glutamic Acid/toxicity , Neurons/drug effects , Neuroprotective Agents/pharmacology , Animals , Calcium/metabolism , Cell Death/drug effects , Cells, Cultured , Chlorogenic Acid/chemistry , Mice, Inbred C57BL , Neurons/cytology , Neurons/metabolism , Nitric Oxide/toxicity
4.
Chem Commun (Camb) ; 51(1): 81-4, 2015 Jan 04.
Article in English | MEDLINE | ID: mdl-25388953

ABSTRACT

We report a conjugate between carbon quantum dots and a NO photoreleaser able to photogenerate the anticancer NO radical via an energy transfer mechanism. This nanohybrid proved toxic to cancer cells in vitro and significantly reduced tumor volume in mice bearing human xenograft BxPC-3 pancreatic tumors upon two-photon excitation with the highly biocompatible 800 nm light.


Subject(s)
Nanostructures/chemistry , Nitric Oxide/chemistry , Quantum Dots/chemistry , Animals , Carbon/chemistry , Cell Line, Tumor , Cell Survival/drug effects , HeLa Cells , Humans , Light , Mice , Mice, Inbred BALB C , Mice, SCID , Nanomedicine , Nitric Oxide/toxicity , Pancreatic Neoplasms/therapy , Photons , Phototherapy , Transplantation, Heterologous
5.
Arch Pharm Res ; 38(6): 1263-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25348868

ABSTRACT

Nitric oxide (NO) induces apoptosis in neuronal cells, and has been implicating in a variety of neuronal pathological process. Thus, there is much interest in identifying natural substances which have protective effects against damage induced by nitrosative stress. The roots of Vitis amurensis have been used as traditional medicine and contain structurally diverse resveratrol oligomers with various biological activities. However, there have been few studies on the protective effect of resveratrol oligomers against neurotoxic reactive nitrogen species. In this study, we evaluated the protective effects of two resveratrol oligomers from V. amurensis, vitisin A and heyneanol A, against NO-induced toxicity. Additionally, their antioxidant activities were determined by measuring NO and hydroxyl radical scavenging ability. Both vitisin A and heyneanol A reduced cell death and DNA fragmentation induced by sodium nitroprusside in SH-SY5Y cells. The present study indicates that radical scavenging activities of vitisin A and heyneanol A contribute to protecting neuronal cells against nitrosative stress.


Subject(s)
Neuroprotective Agents/therapeutic use , Neurotoxicity Syndromes/prevention & control , Nitroprusside/toxicity , Stilbenes/therapeutic use , Vitis/chemistry , Antioxidants/pharmacology , Benzofurans/pharmacology , Cell Line , DNA Fragmentation/drug effects , Free Radical Scavengers/pharmacology , Humans , Hydroxyl Radical/metabolism , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/toxicity , Phenols/pharmacology , Plant Roots/chemistry , Reactive Nitrogen Species/metabolism , Resveratrol , Stilbenes/pharmacology
6.
PLoS One ; 9(7): e103562, 2014.
Article in English | MEDLINE | ID: mdl-25072795

ABSTRACT

Vitamin E has been shown to have strong anticarcinogenic properties, including antioxidant characteristics, making it an ideal candidate for use in combination with immunotherapies that modify the tumor microenvironment. The tumor microenvironment contains immunosuppressive components, which can be diminished, and immunogenic components, which can be augmented by immunotherapies in order to generate a productive immune response. In the current study, we employ the α-tocopherol succinate isomer of vitamin E to reduce immunosuppression by myeloid derived suppressor cells (MDSCs) as well as adoptive transfer of antigen-specific CD8+ T cells to generate potent antitumor effects against the HPV16 E7-expressing TC-1 tumor model. We show that vitamin E alone induces necrosis of TC-1 cells and elicits antitumor effects in TC-1 tumor-bearing mice. We further demonstrate that vitamin E reverses the suppression of T cell activation by MDSCs and that this effect is mediated in part by a nitric oxide-dependent mechanism. Additionally, treatment with vitamin E reduces the percentage of MDSCs in tumor loci, and induces a higher percentage of T cells, following T cell adoptive transfer. Finally, we demonstrate that treatment with vitamin E followed by E7-specific T cell adoptive transfer experience elicits potent antitumor effects in tumor-bearing mice. Our data provide additional evidence that vitamin E has anticancer properties and that it has promise for use as an adjuvant in combination with a variety of cancer therapies.


Subject(s)
CD8-Positive T-Lymphocytes/drug effects , Myeloid Cells/drug effects , alpha-Tocopherol/pharmacology , Animals , CD11b Antigen/metabolism , CD8-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/immunology , Disease Models, Animal , Female , Immunotherapy, Adoptive , Mice , Mice, Inbred C57BL , Myeloid Cells/cytology , Myeloid Cells/metabolism , Necrosis , Neoplasms/immunology , Neoplasms/pathology , Neoplasms/therapy , Nitric Oxide/chemistry , Nitric Oxide/toxicity , Papillomavirus E7 Proteins/immunology , Papillomavirus E7 Proteins/metabolism , alpha-Tocopherol/therapeutic use
7.
J Assist Reprod Genet ; 30(8): 1063-72, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23832270

ABSTRACT

PURPOSE: Previous studies reported that patients with endometriosis had excess nitric oxide (NO) in the reproductive tract and poor embryo development in IVF cycles. This study aims to elucidate the effects of NO on early embryo development. METHODS: Zygotes from superovulated B6CBF1 mice were cultured to blastocysts in a variety of media. Sodium nitroprusside (SNP) and N(G)-nitro-L-arginine (LNA) were added to the culture medium as a NO donor and a NO synthase inhibitor, respectively. The localization and fluorescence intensity of S-nitrosylated (SNO) proteins within 2-cell stage embryos were analyzed with confocal microscopy. Apoptosis and ATP production in the blastocysts were measured. RESULT(S): Subsequent to NO exposure, the SNO proteins mainly colocalized with the mitochondria and endoplasmic reticulum and the intensity of SNO proteins increased. The addition of a quanylate cyclase inhibitor and a cyclic GMP mimic agent induced nonsignificant changes in SNO proteins, whereas addition of a superoxide scavenger or a reduced form of glutathione rescued the embryos from the effects of NO. However, superoxide scavenger supplementation resulted in decreased blastocyst ATP production. CONCLUSION(S): Elevated NO exerts deleterious effects on embryo development, possibly through protein S-nitrosylation in the mitochondria and endoplasmic reticulum. Including glutathione as a component in the culture medium might counteract this effect.


Subject(s)
Apoptosis , Blastocyst/drug effects , Embryonic Development/drug effects , Mitochondria/drug effects , Nitric Oxide/toxicity , Animals , Blastocyst/cytology , Blastocyst/ultrastructure , Embryo Culture Techniques , Mice , Mitochondria/metabolism , Mitochondria/physiology
8.
Arch Pharm Res ; 35(1): 163-70, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22297755

ABSTRACT

Seven prenylated flavanoids, licoflavone C (1), cyclomulberrin (2), neocyclomorusin (3), sanggenon I (4), morusin (5), kuwanon U (6) and kuwanon E (7), and three 2-arylbenzofurans, moracin P (8), moracin O (9), and mulberrofuran Q (10) were isolated from the MeOH extract of Mori Cortex Radicis. Among these, compounds 2-7 enhanced cell viability in a dose-dependent manner against sodium nitroprusside-induced cell death in neuroblastoma SH-SY5Y cells, which was measured by MTT reduction assay (EC(50) values of 4.4, 5.6, 8.0, 6.4, 8.7, and 11.9 µg/mL, respectively). Among 10 compounds, C-3 prenylated flavones (2, 3, and 5) and prenylated flavanones (4, 6, and 7) showed cell protection. However, compound 1 which lacks the prenyl group at C-3 and three 2-arylbenzofurans (8-10) did not show protective effect. The order of cell protection was as follow: C-3 prenylated flavones (2, 3, and 5) > prenylated flavanones (4, 6, and 7) > 2-arylbenzofurans (8-10) and flavone (1). From this result, we show that some prenylated flavones and flavanones might protect neuronal cells against nitrosative stress-mediated cell death. Even though further evaluations are necessary in vitro and in vivo study, we carefully suggest that some prenylated flavonoids from Mori Cortex Radicis might protect neuronal cells from neurodegenerative diseases.


Subject(s)
Flavonoids/pharmacology , Moraceae , Neuroblastoma/pathology , Nitric Oxide/toxicity , Plant Extracts/pharmacology , Prenylation , Cell Death/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Cytoprotection/drug effects , Dose-Response Relationship, Drug , Flavonoids/isolation & purification , Flavonoids/therapeutic use , Humans , Moraceae/chemistry , Plant Extracts/isolation & purification , Plant Extracts/therapeutic use
9.
Nitric Oxide ; 24(3): 151-9, 2011 Apr 30.
Article in English | MEDLINE | ID: mdl-21354319

ABSTRACT

No pro-apoptotic effect of dinitrosyl iron complexes (DNIC) with glutathione, cysteine or thiosulfate was established after incubation of HeLa cells in Eagle's medium. However, DNIC with thiosulfate manifested pro-apoptotic activity during incubation of HeLa cells in Versene's solution supplemented with ethylene diamine tetraacetate (EDTA) known to induce the decomposition of these DNIC. The water-soluble о-phenanthroline derivative bathophenanthroline disulfonate (BPDS) had a similar effect on DNIC with glutathione during incubation of HeLa cells in Eagle's medium. It was assumed that EDTA- or BPDS-induced pro-apoptotic effect of DNIC with thiosulfate or glutathione is coupled with the ability of decomposing DNIC to initiate S-nitrosylation of proteins localized on the surface of HeLa cells. Presumably, the pro-apoptotic effect of S-nitrosoglutathione (GS-NO) on HeLa cells preincubated in Eagle's medium is mediated by the same mechanism, although the pro-apoptotic effect based on the ability of GS-NO to initiate the release of significant amounts of NO and its oxidation to cytotoxic peroxynitrite in a reaction with superoxide should not be ruled out either. No apoptotic activity was found in the presence of bivalent iron and glutathione favoring the conversion of GS-NO into DNIC with glutathione. It is suggested that interaction of HeLa cells with intact DNIC with glutathione or thiosulfate results in the formation of DNIC bound to cell surface proteins.


Subject(s)
Apoptosis/drug effects , Iron/toxicity , Nitric Oxide Donors/toxicity , Nitric Oxide/metabolism , Nitrogen Oxides/toxicity , Sulfhydryl Compounds/toxicity , Chelating Agents/metabolism , Chelating Agents/toxicity , Cysteine/metabolism , Edetic Acid/metabolism , Edetic Acid/toxicity , Glutathione/metabolism , HeLa Cells , Humans , Iron/metabolism , Ligands , Nitric Oxide/toxicity , Nitric Oxide Donors/metabolism , Nitrogen Oxides/metabolism , Oxidants/metabolism , Oxidants/toxicity , Oxidation-Reduction , Phenanthrolines/metabolism , Phenanthrolines/toxicity , S-Nitrosoglutathione/metabolism , S-Nitrosoglutathione/toxicity , Sulfhydryl Compounds/metabolism , Thiosulfates/metabolism , Thiosulfates/toxicity
10.
Zhen Ci Yan Jiu ; 32(4): 285-8, 2007 Aug.
Article in Chinese | MEDLINE | ID: mdl-17907396

ABSTRACT

In the present paper, the authors review the current development of studies on mechanisms of acupuncture treatment of acute ischemic cerebral apoplexy from (1) blood rheology, (2) cerebral microcirculation, 3) metabolism of cerebral tissue, (4) cerebral electrical activity, (5) free radicals and lipid peroxidation reaction, (6) excitatory aminoacid, (7) calcium overload, (8) nitrogen monoxidum, and (9) cerebral apoptosis. Cerebral stroke includes ischemic stroke and hemorrhagic stroke. Ischemic cerebral stroke accounted for about 60%-70% of all the stroke cases. At present, the main remedies for treating acute ischemic cerebral stroke includes thrombolysis, anti-platelet aggregation, improving microcirculation and symptomatic therapy. In stroke, highlighting the efficacy of acupuncture therapy in the treatment of stroke.


Subject(s)
Acupuncture Therapy , Brain Ischemia/therapy , Stroke/therapy , Acute Disease , Apoptosis , Calcium/metabolism , Free Radicals , Humans , Lipid Peroxidation , Nitric Oxide/toxicity
11.
Biochem Pharmacol ; 70(4): 590-7, 2005 Aug 15.
Article in English | MEDLINE | ID: mdl-15993853

ABSTRACT

Nitric oxide (NO) is a widely recognized mediator of physiological and pathophysiological signal transmission. In an attempt to better understand the molecular actions of NO in astrocytes, stress protein expression in response to NO donor sodium nitroprusside was investigated. Heme oxygenase-1 (HO-1) has been identified as an inducer of manganese superoxide dismutase (MnSOD), playing a cytoprotective role under the condition of nitrosative stress. We present evidence that the sequential induction of HO-1 and MnSOD protects astrocytes from NO toxicity: (1) both HO-1 and MnSOD expression were induced by NO; (2) NO-mediated increase in MnSOD activity was partly abolished by HO-1 inhibitor Zn(II) protoporphyrin IX (ZnPP); (3) pretreatment of astrocytes with a nontoxic dose of NO protected the cells against the later treatment with a toxic dose of NO; (4) inhibition of HO-1 by ZnPP sensitized astrocytes to the nontoxic dose of NO resulting in a marked cytotoxicity; and (5) adenovirus-mediated overexpression of MnSOD protected astrocytes from the NO toxicity. The molecular action of NO in astrocytes appears to be dose-dependent. While a high dose of NO exerts cytotoxicity leading to the tissue damage in the central nervous system, a low dose of NO may act as an important signaling molecule in astrocytes with concurrent induction of cytoprotective proteins such as HO-1 and MnSOD.


Subject(s)
Astrocytes/enzymology , Heme Oxygenase (Decyclizing)/biosynthesis , Nitric Oxide/physiology , Superoxide Dismutase/biosynthesis , Animals , Astrocytes/cytology , Blotting, Western , Cells, Cultured , Electrophoresis, Gel, Two-Dimensional , Enzyme Induction , Mice , Mice, Inbred ICR , Nitric Oxide/toxicity , Reverse Transcriptase Polymerase Chain Reaction
12.
Fish Shellfish Immunol ; 15(3): 241-8, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12892745

ABSTRACT

Virulent strains of Photobacterium damselae subsp. piscicida (Pdp) were grown in media with or without glucose supplementation (to enhance polysaccharide capsule formation) and the bactericidal action of nitric oxide (NO) and peroxynitrites was evaluated in a cell-free assay. Treatment with the NO-donor S-nitroso-acetyl-penicillamine (SNAP) induced a dose-and time-dependent decrease in Pdp survival. This effect was greater for strains grown without glucose supplementation (C forms) than for their counterparts grown with glucose supplementation (C(+) forms). Addition of superoxide anion (O2(-)) generating systems (Xanthine/Xanthine oxidase, glucose/glucose oxidase) to the culture media further enhanced the bactericidal effect of NO. A similar bactericidal effect, with the same pattern of sensitivity, was observed when C+ and C forms of the bacteria were treated with 3-morpholino-sydonimide hydrochloride (SIN-1), a compound which simultaneously generates NO and O2(-). Addition of superoxide dismutase (SOD) or SOD plus catalase (CAT) did not fully reverse the toxic action of SIN-1 and the bactericidal effect was similar for both C and C(+) forms suggesting that while NO alone is sufficient to cause damage in all strains of the pathogen tested, growth in glucose supplemented medium enhanced protection to reactive oxygen intermediates rather than NO.


Subject(s)
Molsidomine/analogs & derivatives , Nitric Oxide/toxicity , Peroxynitrous Acid/toxicity , Photobacterium/drug effects , Analysis of Variance , Culture Media , Glucose/metabolism , Molsidomine/metabolism , Photobacterium/metabolism , S-Nitroso-N-Acetylpenicillamine/metabolism
13.
Cell Mol Biol (Noisy-le-grand) ; 48(6): 693-7, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12396081

ABSTRACT

Beta-amyloid (Abeta) deposition likely plays a causal role in the lesions that occur in Alzheimer's disease (AD). The Ginkgo biloba extract EGb 761 is widely prescribed in the treatment of cognitive deficits that are associated with normal and pathological brain aging such as AD. We have investigated here the potential effectiveness of EGb 761 against cell death produced by Abeta fragments on primary cultures of hippocampal cells, these cells being severely damaged in AD. A co-treatment with EGb 761 protected cells against toxicity induced by Abeta fragments in a concentration dependent manner. The effect of EGb 761 was even significant if added up to 8 hr to cells and was shared by its flavonoid fraction CP 205, whereas the terpenes bilobalide and ginkgolide B were ineffective. EGb 761 also displayed protective effects against toxicity produced by either H2O2 or nitric oxide, two neurotoxic agents that possibly mediate Abeta toxicity. Moreover, EGb 761, and to a lesser extent CP 205, completely blocked Abeta-induced events, such as reactive oxygen species accumulation and apoptosis. Taken together, these results and those obtained by other groups highlight the neuroprotective abilities of EGb 761 against dysfunction and death of neurons caused by Abeta deposits.


Subject(s)
Amyloid beta-Peptides/drug effects , Amyloid beta-Peptides/toxicity , Neuroprotective Agents/pharmacology , Plant Extracts/pharmacology , Animals , Antioxidants/pharmacology , Apoptosis/drug effects , Ginkgo biloba , Hippocampus/drug effects , Hydrogen Peroxide/toxicity , Nitric Oxide/toxicity , Oxidative Stress/drug effects , Rats
14.
Am J Respir Crit Care Med ; 163(7): 1676-82, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11401893

ABSTRACT

Inhalation of nitric oxide (NO) is useful for the treatment of patients with pulmonary hypertension. However, the potential toxicity of inhaled NO is still unclear. Coagulation activation plays an important role in lung injury. We assessed the effect of low- and high-dose inhaled NO on the coagulation system in the intraalveolar space of mice. The animals were assigned to five groups (n = 6): [RA] group, mice exposed to fresh air alone; [RA+2 ppm NO] group, fresh air and 2 ppm NO; [RA+40 ppm NO] group, fresh air and 40 ppm NO; [RA+2 ppm NO+O(2)] group, fresh air, 2 ppm NO and O(2); and [RA+40 ppm NO+O(2)] group, fresh air, 40 ppm NO and O(2). Each group was treated for 3 wk. Lung specimens of [RA+40 ppm NO] and [RA+40 ppm NO+O(2)] groups showed significant nitrotyrosine immunoreactivity. BALF concentrations of total protein, thrombin and soluble tissue factor were significantly increased in mice of [RA+40 ppm NO] and [RA+40 ppm NO+O(2)] groups compared with [RA] group. However, BALF concentrations of total protein, thrombin, and soluble tissue factor were not significantly increased in mice of [RA+2 ppm NO] and [RA+2 ppm NO+O(2)] groups compared with [RA] group. Lung tissue factor mRNA expression was higher in the high-dose NO group than in the low-dose NO group. NO donor increased significantly tissue factor activity on alveolar epithelial cells. This study has shown for the first time that long-term inhalation of high, but not low, concentration of NO may activate the clotting system by increasing the lung expression of tissue factor.


Subject(s)
Nitric Oxide/toxicity , Pulmonary Alveoli/metabolism , Thrombin/metabolism , Thromboplastin/metabolism , Tyrosine/analogs & derivatives , Administration, Inhalation , Animals , Blood Coagulation , Bronchi/chemistry , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/cytology , Cell Line , Female , Immunohistochemistry , Lung/metabolism , Lung/pathology , Mice , Mice, Inbred C57BL , Nitrates/analysis , Nitric Oxide/administration & dosage , Nitric Oxide Donors/pharmacology , Nitrites/analysis , Nitro Compounds/pharmacology , Proteins/analysis , Reverse Transcriptase Polymerase Chain Reaction , Tyrosine/analysis
15.
J Infect Dis ; 183(9): 1388-94, 2001 May 01.
Article in English | MEDLINE | ID: mdl-11294671

ABSTRACT

Iron chelation therapy of Plasmodium falciparum infection alleviates the clinical course of cerebral malaria in children. This study assessed the underlying mechanisms of this therapy. Cytokine stimulation of human (intestinal cell line DLD-1) or murine cells (murine macrophage cell line RAW 264.7) resulted in increased nitric oxide (NO) formation and decreased survival of plasmodia within cocultured human erythrocytes. The addition of desferrioxamine (DFO) before cytokine treatment increased both NO formation and parasite killing but had no effect in the presence of the inhibitor of NO formation, L-N6-(1-iminoethyl)-lysine. Moreover, peroxynitrite, which is formed after chemical reaction of NO with superoxide, appears to be the principal effector molecule for macrophage-mediated cytotoxicity toward P. falciparum, and interferon-gamma is a major regulatory cytokine for this process. The effect of DFO on the clearance of plasmodia appears to be due to enhanced generation of NO, rather than to limitation of iron availability to the parasite.


Subject(s)
Deferoxamine/therapeutic use , Iron Chelating Agents/therapeutic use , Iron/metabolism , Malaria, Falciparum/immunology , Nitric Oxide/biosynthesis , Plasmodium falciparum/drug effects , Animals , Cells, Cultured , Coculture Techniques , Erythrocytes/immunology , Erythrocytes/parasitology , Humans , Interferon-gamma/immunology , Lipopolysaccharides/immunology , Macrophages/immunology , Macrophages/parasitology , Malaria, Falciparum/drug therapy , Mice , Nitric Oxide/toxicity , Plasmodium falciparum/immunology , Plasmodium falciparum/metabolism , RNA, Messenger/analysis , Superoxide Dismutase/metabolism , Tumor Cells, Cultured
16.
J Agric Food Chem ; 48(11): 5768-72, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11087552

ABSTRACT

It is found that green tea and black tea are able to protect against nitric oxide (NO(*)) toxicity in several ways. Both green tea and black tea scavenge NO(*) and peroxynitrite, inhibit the excessive production of NO(*) by the inducible form of nitric oxide synthase (iNOS), and suppress the LPS-mediated induction of iNOS. The NO(*) scavenging activity of tea was less than that of red wine. The high activity found in the polyphenol fraction of black tea (BTP) could not be explained by the mixed theaflavin fraction (MTF) or catechins [epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate (EGCG)], which were tested separately. Synergistic effects between the compounds, or the presence of a potent, unidentified NO(*) scavenger, may explain the high activity of BTP. The peroxynitrite scavenging of tea was comparable to that of red wine. The main activity was found in the polyphenol fraction. MTF and the catechins were found to be potent peroxynitrite scavengers. Tea and tea components were effective inhibitors of iNOS. Of the tea components tested, only MTF had an activity higher than that of the tea powders. The polyphenol fractions of tea were much more active than the tea powders in suppressing the induction of iNOS. On the basis of its abundance and activity, EGCG was the most active inhibitor. The protective effect of tea on NO(*) toxicity is discussed in relation to the beneficial effect of flavonoid intake on the occurrence of cardiovascular heart disease.


Subject(s)
Flavonoids , Nitric Oxide/toxicity , Phenols/pharmacology , Polymers/pharmacology , Tea , Wine , Animals , Cell Line , Enzyme Induction/drug effects , Lipopolysaccharides/pharmacology , Macrophages, Alveolar/enzymology , Nitrates/antagonists & inhibitors , Nitrates/metabolism , Nitrates/toxicity , Nitric Oxide/antagonists & inhibitors , Nitric Oxide Synthase/biosynthesis , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Nitrites/metabolism , Phytotherapy , Polyphenols , Rats , Tea/therapeutic use
17.
Gen Pharmacol ; 34(5): 303-10, 2000 May.
Article in English | MEDLINE | ID: mdl-11368885

ABSTRACT

Samultang has been traditionally used for treatment of ischemic heart and brain diseases in oriental medicine. However, little is known about the mechanism by which Samultang rescues the myocardial and neuronal cells from ischemic damage. This study was designed to evaluate whether the water extract of Samultang may modulate the production of nitric oxide (NO) in LPS and PMA treated-C6 glial cells to protect the cells from NO-induced cytotoxicity. C6 glial cells treated with both LPS and PMA significantly produced a large amount of NO compared to untreated, PMA, or LPS-treated cells. In parallel with NO production, cotreatment of LPS and PMA induced the severe apoptotic death of C6 glial cells. However, Samultang significantly reduced both cell death and NO production by LPS/PMA in a dose-dependent manner. In addition, the modulatory effects of Samultang on LPS/PMA-induced cytotoxicity and NO production could be mimicked by exogenous treatments of N(G)MMA, a nitric oxide synthase (NOS) inhibitor, and pyrrolidine dithiocarbamate (PDTC), a strong NF-kappaB inhibitor. Treatment of C6-glial cells with LPS/PMA induced the transcriptional activation of NF-kappaB, which was markedly inhibited by Samultang. Taken together, we suggest that the protective effects of Samultang against LPS/PMA-induced cytotoxicity may be mediated by the suppression of NO synthesis via down-regulation of NF-kappaB activation.


Subject(s)
Drugs, Chinese Herbal/pharmacology , Lipopolysaccharides/toxicity , NF-kappa B/drug effects , NF-kappa B/physiology , Neuroglia/drug effects , Nitric Oxide/biosynthesis , Nitric Oxide/toxicity , Tetradecanoylphorbol Acetate/toxicity , Cell Survival/drug effects , Down-Regulation/drug effects , Down-Regulation/physiology , Enzyme Inhibitors/pharmacology , Humans , Nitric Oxide Synthase/antagonists & inhibitors , omega-N-Methylarginine/pharmacology
18.
Wound Repair Regen ; 6(6): 569-77, 1998.
Article in English | MEDLINE | ID: mdl-9893176

ABSTRACT

A full-thickness wound model was used to evaluate the effects of a topically applied polyethyleneimine-based nitric oxide donor on wound repair in aged rats. Polymer applications were applied over a 10-day period on days 0, 2, 4, 6, and 8 comparing treatment (linear polyethyleneimine-nitric oxide) and control groups (linear polyethyleneimine). Urinary nitrate excretion was quantified as a measure of nitric oxide released. The nitric oxide released from the linear polyethyleneimine-nitric oxide group was significant compared with controls (p

Subject(s)
Bandages/standards , Nitric Oxide/toxicity , Nitric Oxide/therapeutic use , Polyethyleneimine/therapeutic use , Vasodilator Agents/toxicity , Vasodilator Agents/therapeutic use , Wound Healing/drug effects , Administration, Cutaneous , Age Factors , Animals , Disease Models, Animal , Drug Carriers , Drug Evaluation, Preclinical , Male , Nitric Oxide/urine , Rats , Rats, Sprague-Dawley , Vasodilator Agents/urine , Wound Healing/physiology
19.
Biochem Pharmacol ; 51(6): 863-8, 1996 Mar 22.
Article in English | MEDLINE | ID: mdl-8602884

ABSTRACT

The diterpenoid ent-8alpha-hydroxy-labda-13(16),14-dien ("labdane F2") was obtained from an anti-inflammatory extract of Sideritis javalambrensis. Labdane F2 inhibited prostaglandin E2 generation in cultured mouse peritoneal macrophages, treated with zymosan, ionophore A23187, or arachidonic acid itself, and in J774 macrophage-like cells activated by bacterial lipopolysaccharide (LPS). The mechanism was investigated by prelabelling the macrophages with radiolabelled arachidonic acid or oleic acid, followed by cell activation in the presence or absence of nontoxic concentrations of labdane F2. Surprisingly, under those conditions in which reduced PGE2 generation was observed, labdane F2 consistently enhanced the release of labelled fatty acid, in a manner similar to that displayed by thimerosal a known acyl-CoA: lysolecithin transferase inhibitor. Labdane E2 therefore appears to possess 2 mutually opposing actions on the eicosanoid system in macrophages: potentiation of delivery of substrate following cell activation, followed by inhibition of conversion of substrate to product. It was also found that nontoxic concentrations of labdane F2 reduced the expression of the inducible isoforms of cyclooxygenase and nitric oxide synthase in LPS-treated J774 cells. Thus, this anti-inflammatory diterpenoid labdane possesses a diverse array of effects impinging on enzyme pathways involved in eicosanoid generation and other inflammatory pathways in macrophages.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Arachidonic Acid/metabolism , Diterpenes/pharmacology , Eicosanoids/biosynthesis , Macrophage Activation/physiology , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/metabolism , Naphthols/pharmacology , Plant Extracts/pharmacology , Animals , Arachidonic Acid/biosynthesis , Dinoprostone/biosynthesis , Lipopolysaccharides/pharmacology , Macrophage Activation/drug effects , Male , Mice , Nitric Oxide/biosynthesis , Nitric Oxide/toxicity , Oleic Acid , Oleic Acids/metabolism , Phospholipids/metabolism , Plants/chemistry , Stimulation, Chemical
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