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1.
PLoS One ; 15(8): e0237569, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817667

RESUMO

Several 'super-complexes' of individual hetero-oligomeric membrane protein complexes, whose function is to facilitate intra-membrane electron and proton transfer and harvesting of light energy, have been previously characterized in the mitochondrial cristae and chloroplast thylakoid membranes. We report the presence of an intra-membrane super-complex dominated by the ATP-synthase, photosystem I (PSI) reaction-center complex and the ferredoxin-NADP+ Reductase (FNR) in the thylakoid membrane. The presence of the super-complex has been documented by mass spectrometry, clear-native PAGE and Western Blot analyses. This is the first documented presence of ATP synthase in a super-complex with the PSI reaction-center located in the non-appressed stromal domain of the thylakoid membrane.


Assuntos
Cloroplastos/metabolismo , Ferredoxina-NADP Redutase/metabolismo , Óxido Nítrico Sintase/metabolismo , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Tilacoides/metabolismo , Trifosfato de Adenosina/metabolismo , Transporte de Elétrons , Fotossíntese , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Spinacia oleracea/crescimento & desenvolvimento , Spinacia oleracea/metabolismo
2.
Am J Physiol Heart Circ Physiol ; 319(2): H271-H281, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32559139

RESUMO

The purpose of this study was to investigate the effect of race and subclinical elevations in blood pressure (i.e., prehypertension) on cutaneous sensory nerve-mediated and nitric oxide (NO)-dependent vasodilation. We recruited participants who self-identified as either non-Hispanic black (n = 16) or non-Hispanic white (n = 16). Within each group, participants were subdivided as either normotensive (n = 8 per group) or prehypertensive (n = 8 per group). Each participant was instrumented with four intradermal microdialysis fibers: 1) control (lactated Ringer's), 2) 5% lidocaine (sensory nerve inhibition), 3) 20 mM Nω-nitro-l-arginine methyl ester (l-NAME) (NO synthase inhibition), and 4) lidocaine + l-NAME. Skin blood flow was assessed via laser-Doppler flowmetry, and each site underwent local heating from 33°C to 39°C. At the plateau, 20 mM l-NAME were infused at control and lidocaine sites to quantify NO-dependent vasodilation. Maximal vasodilation was induced via 54 mM sodium nitroprusside and local heating to 43°C. Data are means ± SD. Sensory nerve-mediated cutaneous vasodilation was reduced in prehypertensive non-Hispanic white (34 ± 7%) and both non-Hispanic black groups (normotensive, 20 ± 9%, prehypertensive, 24 ± 15%) relative to normotensive non-Hispanic whites (54 ± 12%). NO-dependent vasodilation was also reduced in prehypertensive non-Hispanic white (41 ± 7%) and both non-Hispanic black groups (normotensive, 44 ± 7%, prehypertensive, 19 ± 7%) relative to normotensive non-Hispanic whites (60 ± 11%). The decrease in NO-dependent vasodilation in prehypertensive non-Hispanic blacks was further reduced relative to all other groups. These data suggest subclinical increases in blood pressure adversely affect sensory-mediated and NO-dependent vasodilation in both non-Hispanic blacks and whites.NEW & NOTEWORTHY Overt hypertension is known to reduce cutaneous sensory nerve-mediated and nitric oxide (NO)-dependent vasodilation, but the effect of subclinical increases in blood pressure (i.e., prehypertension) is unknown. The combined effect of race and prehypertension is also unknown. In this study, we found that prehypertension reduces cutaneous sensory nerve-mediated and NO-dependent vasodilation in both non-Hispanic white and black populations, with the greatest reductions observed in prehypertensive non-Hispanic blacks.


Assuntos
Pressão Sanguínea , Vasos Sanguíneos/inervação , Vasos Sanguíneos/metabolismo , Células Endoteliais/metabolismo , Óxido Nítrico/metabolismo , Pré-Hipertensão/fisiopatologia , Células Receptoras Sensoriais , Pele/irrigação sanguínea , Vasodilatação , Administração Cutânea , Adolescente , Adulto , Afro-Americanos , Anestésicos Locais/administração & dosagem , Vasos Sanguíneos/efeitos dos fármacos , Estudos de Casos e Controles , Células Endoteliais/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Grupo com Ancestrais do Continente Europeu , Feminino , Georgia/epidemiologia , Humanos , Masculino , Microdiálise , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Pré-Hipertensão/diagnóstico , Pré-Hipertensão/etnologia , Pré-Hipertensão/metabolismo , Fatores Raciais , Células Receptoras Sensoriais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/administração & dosagem , Adulto Jovem
3.
Acta Cir Bras ; 35(2): e202000205, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428061

RESUMO

Purpose To investigate the effects of induction of selective liver hypothermia in a rodent model. Methods Seven male Wistar rats were subjected to 90 minutes of partial 70% liver ischemia and topic liver 26°C hypothermia (H group). Other seven male Wistar rats were subjected to 90 minutes of partial 70% normothermic liver ischemia (N group). Five additional rats underwent a midline incision and section of liver ligaments under normothermic conditions and without any liver ischemia (sham group). All animals were sacrificed 24-h after reperfusion, and livers were sampled for analyses. Pathology sections were scored for sinusoidal congestion, ballooning, hepatocelllular necrosis and the presence of neutrophilic infiltrates. Results At the end of the experiment, liver tissue expressions of TNF-ɑ, IL-1ß, iNOS and TNF-ɑ/IL-10 ratio were significantly reduced in the H group compared to N group, whereas IL-10 and eNOS were significantly increased in H group. Histopathological injury scores revealed a significant decrease in ischemia/reperfusion (I/R) injuries in H group. Conclusion Selective liver hypothermia prevented I/R injury by inhibiting the release of inflammatory cytokines, preserves microcirculation, prevents hepatocellular necrosis and leukocyte infiltration, allowing maintenance of the liver architecture.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Hipotermia Induzida/métodos , Fígado/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Lesão Pulmonar Aguda/patologia , Animais , Temperatura Corporal , Citocinas/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Isquemia/patologia , Fígado/patologia , Masculino , Necrose/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Fator de Necrose Tumoral alfa
4.
Life Sci ; 254: 117819, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32442451

RESUMO

AIMS: Vascular dysfunction plays a key role in sepsis but the role of perivascular adipose tissue (PVAT) in this condition is relatively unknown. MAIN METHODS: Sepsis was induced by cecal ligation and puncture (CLP). The responses of the aorta and superior mesenteric artery to norepinephrine in the presence or absence of PVAT were evaluated. Fluorescent probes measured the production of nitric oxide (NO) and reactive oxygen species (ROS). NO synthases (NOS) and ß3-adrenoceptor expression were detected by immunofluorescence and S-nitrosylation by the biotin switch assay. KEY FINDINGS: Aorta and superior mesenteric arteries from septic animals with intact PVAT showed a worsened response to the vasoconstrictor compared to vessels without PVAT. PVAT from the aorta (APVAT) produced NO and ROS whereas PVAT from the superior mesenteric artery (MPVAT) produced only ROS. Septic APVAT exhibited a higher density of NOS-1 and NOS-3. S-nitrosylation was found in APVAT. Donor (PVAT obtained from normal or septic rats):Host (normal vessel without PVAT) experiments showed that L-NAME, ODQ and ß3-adrenergic receptor antagonist blocked the septic APVAT anti-contractile effect. None of these compounds affected MPVAT; tempol, but not apocynin, blocked its anti-contractile effect. SIGNIFICANCE: PVAT contributes to the anti-contractile effect in the aorta and mesenteric artery of septic rats through different pathways. ß3-Adrenergic receptor and NO appear to be key mediators of this effect in APVAT, but not in MPVAT where ROS seem to be a relevant mediator. Therefore, PVAT is a relevant player of sepsis vascular dysfunction.


Assuntos
Aorta/metabolismo , Artérias Mesentéricas/metabolismo , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores Adrenérgicos beta 3/fisiologia , Sepse/fisiopatologia , Acetofenonas/farmacologia , Tecido Adiposo/metabolismo , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Animais , Óxidos N-Cíclicos/farmacologia , Feminino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/metabolismo , Norepinefrina/farmacologia , Oxidiazóis/farmacologia , Fenótipo , Quinoxalinas/farmacologia , Ratos , Receptores Adrenérgicos beta 3/biossíntese , Marcadores de Spin , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologia
5.
Arch Biochem Biophys ; 690: 108430, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32473132

RESUMO

BACKGROUND: The severity and duration of hypoxia is known to determine apoptotic fate in heart; however, its implication during myocardial infarction (MI) remains unaddressed. Therefore the aim of the study was to determine apoptotic regulation in cardiomyocytes under varied hypoxic intensity and duration and to unravel the role of HIF-1α in such modulation. METHODS: Treatment of cardiomyocytes to varied hypoxic intensity and duration was carried out in vitro, which was mimicked in vivo by dose-dependent Isoproterenol hydrochloride treatment for varied time-points. Myocardium-targeted HIF-1α knockdown in vivo was performed to decipher its role in cardiomyocyte apoptosis under varied stress. Signaling intermediates were analyzed by RT-PCR, immunoblotting and co-immunoprecipitation. DCFDA-based ROS assay, Griess assay for NO release and biochemical assays for estimating caspase activity were performed. RESULTS: Severe stress resulted in cardiomyocyte apoptosis in both shorter and longer time-points. Moderate stress, on the other hand, induced apoptosis only in the shorter time-point which was downregulated in the longer time-point. ROS activity was upregulated under severe hypoxic stress for both time-points and only in the early time-point under moderate hypoxia. Increased ROS accumulation activated ERK-1/2 which stabilized nuclear HIF-1α, promoting bnip3-mediated apoptosis. Stable HSP90-IRE-1 association in such cells caused elevated endoplasmic reticulum stress-related caspase-12 activity. Sustained moderate hypoxia caused decline in ROS activity, but upregulated NFκB-dependent NO generation. NO-stabilized HIF-1α was predominantly cytosolic, since low ROS levels downregulated ERK-1/2 activity, thereby suppressing bnip3 expression. Cytosolic HIF-1α in such cells sequestered HSP90 from IRE-1, downregulating caspase-12 activity due to proteasomal degradation of IRE-1. Accordingly, myocardium-specific in vivo silencing of HIF-1α was beneficial at both time-points under severe stress as also for lesser duration of moderate stress. However, silencing of HIF-1α aggravated apoptotic injury during sustained moderate stress. CONCLUSION: ROS-mediated HIF-1α stabilization promotes cardiomyocyte apoptosis on one hand while NO-mediated stabilization of HIF-1α disrupts apoptosis depending upon the severity and duration of hypoxia. Therefore the outcome of modulation of cardiac HIF-1α activity is regulated by both the severity and duration of ischemic stress.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Infarto do Miocárdio/fisiopatologia , Animais , Apoptose , Caspase 12/metabolismo , Hipóxia Celular , Linhagem Celular , Estresse do Retículo Endoplasmático , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Humanos , Mutação , Miócitos Cardíacos/citologia , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/metabolismo , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais , Fatores de Tempo , Transfecção
6.
Nat Commun ; 11(1): 1614, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32235841

RESUMO

The heterocycle 1,2,3-triazole is among the most versatile chemical scaffolds and has been widely used in diverse fields. However, how nature creates this nitrogen-rich ring system remains unknown. Here, we report the biosynthetic route to the triazole-bearing antimetabolite 8-azaguanine. We reveal that its triazole moiety can be assembled through an enzymatic and non-enzymatic cascade, in which nitric oxide is used as a building block. These results expand our knowledge of the physiological role of nitric oxide synthase in building natural products with a nitrogen-nitrogen bond, and should also inspire the development of synthetic biology approaches for triazole production.


Assuntos
Bactérias/metabolismo , Óxido Nítrico/metabolismo , Triazóis/metabolismo , Azaguanina/metabolismo , Bactérias/enzimologia , Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Produtos Biológicos , Vias Biossintéticas/genética , Genes Bacterianos/genética , Óxido Nítrico Sintase/metabolismo , Nitrogênio , Streptomyces/enzimologia , Streptomyces/genética , Streptomyces/metabolismo , Biologia Sintética
7.
Vascular ; 28(5): 619-628, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32295493

RESUMO

OBJECTIVES: To detect the vascular tension and nitric oxide (NO) release synchronously in mice pulmonary artery, we perform two experiments and present a novel application of confocal wire myograph coupled with the confocal laser scanning microscopy. METHODS: In the first experiment, viable endothelium-intact mouse pulmonary artery (outer diameter 100-300 µM) rings underwent a one-hour preincubation with a NO-specific fluorescent dye, 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate Calbiochem (2.5 µM), and then precontracted with phenylephrine (Phen, 10-6 M), and subsequently dilated in acetylcholine (ACh, 10-6 M - 10-4 M). The endothelium-dependent vasorelaxation and NO generation in pulmonary artery rings were simultaneously recorded. In the second experiment, after 30-min incubation with the former NO fluorescent dye, the qualified pulmonary artery rings were co-incubated for another 30 min with a nitric oxide synthase inhibitor, 10-4 M Nω-nitro-L-arginine-methyl-ester (L-NAME), and then pretreated with Phen (10-6 M) followed by ACh (10-5 M). The Ach-induced vasodilation and NO release were recorded simultaneously. RESULTS: ACh (10-6 M - 10-4 M) promoted pulmonary artery relaxation and intracellular NO release in a dose-dependent manner. Additionally, L-NAME (10-4 M) significantly attenuated the vasodilatation and the intracellular NO release. CONCLUSIONS: This combined application visually confirms that the synchronous changes in Ach induced vasodilation and NO release, which provides a new method for cardiovascular research.


Assuntos
Endotélio Vascular/metabolismo , Microscopia Confocal , Miografia , Óxido Nítrico/metabolismo , Artéria Pulmonar/metabolismo , Vasodilatação , Acetilcolina/farmacologia , Animais , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Masculino , Camundongos Endogâmicos ICR , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Artéria Pulmonar/efeitos dos fármacos , Fatores de Tempo , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
8.
Braz J Med Biol Res ; 53(3): e8761, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159612

RESUMO

Nitric oxide (NO) inhibition by high-dose NG-nitro-L-arginine methyl ester (L-NAME) is associated with several detrimental effects on the cardiovascular system. However, low-dose L-NAME increases NO synthesis, which in turn induces physiological cardiovascular benefits, probably by activating a protective negative feedback mechanism. Aerobic exercise, likewise, improves several cardiovascular functions in healthy hearts, but its effects are not known when chronically associated with low-dose L-NAME. Thus, we tested whether the association between low-dose L-NAME administration and chronic aerobic exercise promotes beneficial effects to the cardiovascular system, evaluating the cardiac remodeling process. Male Wistar rats were randomly assigned to control (C), L-NAME (L), chronic aerobic exercise (Ex), and chronic aerobic exercise associated to L-NAME (ExL). Aerobic training was performed with progressive intensity for 12 weeks; L-NAME (1.5 mg·kg-1·day-1) was administered by orogastric gavage. Low-dose L-NAME alone did not change systolic blood pressure (SBP), but ExL significantly increased SBP at week 8 with normalization after 12 weeks. Furthermore, ExL promoted the elevation of left ventricle (LV) end-diastolic pressure without the presence of cardiac hypertrophy and fibrosis. Time to 50% shortening and relaxation were reduced in ExL, suggesting a cardiomyocyte contractile improvement. In addition, the time to 50% Ca2+ peak was increased without alterations in Ca2+ amplitude and time to 50% Ca2+ decay. In conclusion, the association of chronic aerobic exercise and low-dose L-NAME prevented cardiac pathological remodeling and induced cardiomyocyte contractile function improvement; however, it did not alter myocyte affinity and sensitivity to intracellular Ca2+ handling.


Assuntos
Cálcio/análise , Inibidores Enzimáticos/farmacologia , Contração Miocárdica/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Adiposidade , Animais , Peso Corporal/fisiologia , Inibidores Enzimáticos/administração & dosagem , Hemodinâmica , Masculino , Modelos Animais , Atividade Motora/fisiologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/fisiologia , NG-Nitroarginina Metil Éster/administração & dosagem , Óxido Nítrico Sintase/metabolismo , Ratos Wistar , Pressão Ventricular/efeitos dos fármacos
9.
Proc Natl Acad Sci U S A ; 117(13): 7516-7523, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32170009

RESUMO

Among CO2-fixing metabolic pathways in nature, the linear Wood-Ljungdahl pathway (WLP) in phylogenetically diverse acetate-forming acetogens comprises the most energetically efficient pathway, requires the least number of reactions, and converts CO2 to formate and then into acetyl-CoA. Despite two genes encoding glycine synthase being well-conserved in WLP gene clusters, the functional role of glycine synthase under autotrophic growth conditions has remained uncertain. Here, using the reconstructed genome-scale metabolic model iSL771 based on the completed genome sequence, transcriptomics, 13C isotope-based metabolite-tracing experiments, biochemical assays, and heterologous expression of the pathway in another acetogen, we discovered that the WLP and the glycine synthase pathway are functionally interconnected to fix CO2, subsequently converting CO2 into acetyl-CoA, acetyl-phosphate, and serine. Moreover, the functional cooperation of the pathways enhances CO2 consumption and cellular growth rates via bypassing reducing power required reactions for cellular metabolism during autotrophic growth of acetogens.


Assuntos
Aminoácido Oxirredutases/metabolismo , Aminometiltransferase/metabolismo , Processos Autotróficos/fisiologia , Complexos Multienzimáticos/metabolismo , Acetilcoenzima A/metabolismo , Aminoácido Oxirredutases/genética , Aminometiltransferase/genética , Proteínas de Bactérias/metabolismo , Ciclo do Carbono , Dióxido de Carbono/metabolismo , Monóxido de Carbono/metabolismo , Clostridium/metabolismo , Redes e Vias Metabólicas , Complexos Multienzimáticos/genética , Família Multigênica , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo
10.
BMC Complement Med Ther ; 20(1): 80, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164648

RESUMO

BACKGROUND: The health benefits of botanicals is linked to their phytochemicals that often exert pleiotropic effects via targeting multiple molecular signaling pathways such as the peroxisome proliferator-activated receptors (PPARs) and the nuclear factor kappaB (NFκB). The PPARs are transcription factors that control metabolic homeostasis and inflammation while the NF-κB is a master regulator of inflammatory genes such as the inducible nitric-oxide synthase that result in nitric oxide (NO) overproduction. METHODS: Extracts of Maerua subcordata (MS) and selected candidate constituents thereof, identified by liquid chromatography coupled to mass spectroscopy, were tested for their ability to induce PPARγ mediated gene expression in U2OS-PPARγ cells using luciferase reporter gene assay and also for their ability to inhibit lipopolysaccharide (LPS) induced NO production in RAW264.7 macrophages. While measuring the effect of test samples on PPARγ mediated gene expression, a counter assay that used U2OS-Cytotox cells was performed to monitor cytotoxicity or any non-specific changes in luciferase activity. RESULTS: The results revealed that the fruit, root, and seed extracts were non-cytotoxic up to a concentration of 30 g dry weight per litre (gDW/L) and induced PPARγ mediated gene expression but the leaf extract showed some cytotoxicity and exhibited minimal induction. Instead, all extracts showed concentration (1-15 gDW/L) dependent inhibition of LPS induced NO production. The root extract showed weaker inhibition. Among the candidate constituents, agmatine, stachydrine, trigonelline, indole-3-carboxyaldehyde, plus ethyl-, isobutyl-, isopropyl, and methyl-isothiocyanates showed similar inhibition, and most showed increased inhibition with increasing concentration (1-100 µM) although to a lesser potency than the positive control, aminoguanidine. CONCLUSION: The present study demonstrated for the first time the induction of PPARγ mediated gene expression by MS fruit, root, and seed extracts and the inhibition of LPS induced NO production by MS fruit, leaf, root, and seed extracts and some candidate constituents thereof.


Assuntos
Capparaceae/química , Expressão Gênica/efeitos dos fármacos , NF-kappa B/metabolismo , Óxido Nítrico Sintase/metabolismo , PPAR gama/metabolismo , Extratos Vegetais/farmacologia , Animais , Etiópia , Frutas/química , Camundongos , Raízes de Plantas/química , Células RAW 264.7 , Sementes/química
11.
Biomed Res Int ; 2020: 6892961, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32149121

RESUMO

Inflammatory mediators and inflammatory cells in the inflammatory microenvironment promote the transformation of normal cells to cancer cells in the early stage of cancer, promote the growth and development of cancer cells, and induce tumor immune escape. The monomeric active ingredient ß-elemene is extracted from the traditional Chinese medicine Curcuma wenyujin and has been proven to have good anti-inflammatory and antitumor activities in clinical applications for more than 20 years in China. Recent studies have found that this traditional Chinese medicine plays a vital role in macrophage infiltration and M2 polarization, as well as in regulating immune disorders, and it even regulates the transcription factors NF-κB and STAT3 to alter inflammation, tumorigenesis, and development. In addition, ß-elemene regulates not only different inflammatory factors (such as TNF-α, IFN, TGF-ß, and IL-6/10) but also oxidative stress in vivo and in vitro. The excellent anti-inflammatory and antitumor effects of ß-elemene and its ability to alter the inflammatory microenvironment of tumors have been gradually elaborated. Although the study of monomeric active ingredients in traditional Chinese medicines is insufficient in terms of quality and quantity, the pharmacological effects of more active ingredients of traditional Chinese medicines will be revealed after ß-elemene.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Sesquiterpenos/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Animais , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , China , Curcuma/química , Humanos , Doenças do Sistema Imunitário/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Medicina Tradicional Chinesa , NF-kappa B , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo , Fator de Transcrição STAT3/efeitos dos fármacos , Sesquiterpenos/química , Fatores de Transcrição/efeitos dos fármacos
13.
Biochemistry (Mosc) ; 85(Suppl 1): S56-S78, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32087054

RESUMO

Oxidative stress resulting from accumulation of reactive oxygen, nitrogen, and halogen species (ROS, RNS, and RHS, respectively) causes the damage of cells and biomolecules. However, over the long evolutionary time, living organisms have developed the mechanisms for adaptation to oxidative stress conditions including the activity of the antioxidant system (AOS), which maintains low intracellular levels of RONS (ROS and RNS) and RHS. Moreover, living organisms have adapted to use low concentrations of these electrophiles for the regulation of cell functions through the reversible post-translational chemical modifications of redox-sensitive amino acid residues in intracellular effectors of signal transduction pathways (protein kinases and protein phosphatases), transcription factors, etc. An important fine-tuning mechanism that ensures involvement of RONS and RHS in the regulation of physiological processes is interconversion between different reactive species. This review focuses on the complex networks of interacting RONS and RHS types and their endogenous sources, such as NOX family of NADPH oxidases, complexes I and III of the mitochondrial electron transport chain, NO synthases, cytochrome P450-containing monooxygenase system, xanthine oxidoreductase, and myeloperoxidases. We highlight that kinetic parameters of reactions involving RONS and RHS determine the effects of these reactive species on cell functions. We also describe the functioning of enzymatic and non-enzymatic AOS components and the mechanisms of RONS and RHS scavenging under physiological conditions. We believe that analysis of interactions between RONS and relationships between different endogenous sources of these compounds will contribute to better understanding of their role in the maintenance of cell redox homeostasis as well as initiation and progression of diseases.


Assuntos
Halogênios/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Antioxidantes/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Radicais Livres/metabolismo , Halogenação , Humanos , Mitocôndrias/enzimologia , NADPH Oxidases/metabolismo , Óxido Nítrico Sintase/metabolismo , Oxirredução , Estresse Oxidativo , Peroxidase/metabolismo , Xantina Desidrogenase/metabolismo
14.
J Vasc Res ; 57(3): 126-135, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32106116

RESUMO

Uterine artery myogenic tone (MT) develops during pregnancy in hemochorial placentates such as rats and humans. The physiological reason for its appearance is not clear, and we reasoned that it may be a late pregnancy (LP) event in preparation for controlling hemorrhage during parturition. We also hypothesized that gestational increases in RhoA-induced vascular smooth muscle (VSM) calcium sensitivity are contributory and occur under the tonic influence of nitric oxide (NO). Second-order pre-placental radial arteries from early-pregnant (day 12, n = 5), mid-pregnant (day 16, n = 5) and LP (day 20, n = 20) rats were used in combination with arteriography, VSM calcium measurements, pharmacological RHO/Rho-associated protein kinase (ROCK) and nitric oxide synthase (NOS) inhibition, and Western blotting. A subgroup of LP animals (LP + LN; n = 5) treated with L-NAME from gestational days 10 to 20 were used to determine the effects of NOS inhibition on MT and RhoA expression. MT was evident throughout pregnancy, but its expression in pressurized vessels was masked by endothelial NO-induced vasodilation during early gestation. RhoA protein expression was upregulated in LP and attenuated by in vivo NOS inhibition (as was MT). In vitro RHO/ROCK inhibition decreased MT in a concentration-dependent manner without reducing VSM calcium. In summary, pressure-dependent uterine artery tone increases with gestational age due to a combination of RhoA-mediated increases in VSM calcium sensitivity and a loss of endothelial NO influence.


Assuntos
Sinalização do Cálcio , Endotélio Vascular/metabolismo , Músculo Liso Vascular/metabolismo , Vasoconstrição , Animais , Feminino , Idade Gestacional , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Gravidez , Ratos Sprague-Dawley , Artéria Uterina/metabolismo , Vasodilatação , Proteínas rho de Ligação ao GTP/metabolismo , Quinases Associadas a rho/metabolismo
15.
Food Chem ; 314: 126203, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31978718

RESUMO

The activity, expression and S-nitrosylation of glycogen phosphorylase (GP), phosphofructokinase (PFK) and pyruvate kinase (PK) was compared between pale, soft and exudative (PSE) and red, firm and non-exudative (RFN) pork. The nitric oxide synthase (NOS) activity of RFN pork was higher than PSE pork (P < 0.05). Glycogen and lactic acid content were significantly different between PSE and RFN samples at 1 h postmortem (P < 0.05). Compared to PSE pork, RFN pork had lower activities and higher S-nitrosylation levels of GP, PFK and PK (P < 0.05). Moreover, GP expression in RFN pork was lower (P < 0.05) while no significant differences of PFK and PK expression were observed between these two groups. These data suggest that protein S-nitrosylation can presumably regulate glycolysis by modulating glycolytic enzymes activities and then regulate the development of PSE pork.


Assuntos
Glicólise , Músculo Esquelético/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Carne de Porco/análise , Animais , Cor , Glicogênio/metabolismo , Glicogênio Fosforilase/metabolismo , Músculo Esquelético/enzimologia , Fosfofrutoquinases/metabolismo , Piruvato Quinase/metabolismo , Suínos
16.
World Neurosurg ; 136: e476-e486, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31953101

RESUMO

OBJECTIVE: The present study was performed to elucidate the role of nitric oxide (NO) and connexin 40 (Cx40) in the induction of cerebral vasospasm after subarachnoid hemorrhage (SAH) in vivo. METHODS: A SAH rat model was established using the double-bleed method. A total of 108 Sprague-Dawley rats weighing 250-300 g were randomly divided into 6 groups: SAH; SAH plus diethylenetriamine (DETA)/NO (exogenous NO donor); SAH plus 8-bromoadenosine (8-Br)-cyclic guanosine monophosphate (cGMP; protein kinase G [PKG] activator); SAH plus DETA/NO plus KT5823 (PKG inhibitor); SAH plus DETA/NO plus 40Gap27 (Cx40 inhibitor); and sham. The changes in the diameter of the branch microvessels in the middle cerebral artery were recorded. The neurological score was evaluated using the Garcia scoring system. Basilar artery (BA) tension was measured using the Danish Myo Technology myograph system. Cx40 protein expression was analyzed using immunofluorescence and Western blotting. Endothelial NO synthase, soluble guanylate cyclase, and PKG protein expression were measured by Western blotting. RESULTS: A considerable narrowing of the cerebral vessels was detected in the SAH group compared with that in the sham group. Moreover, compared with the sham group, the SAH group showed a marked decrease in Cx40, endothelial NO synthase, soluble guanylate cyclase, and PKG expression. The expression of Cx40 and PKG were obviously higher in the SAH plus DETA/NO and SAH plus 8-Br-cGMP groups than in the SAH group. However, Cx40 was lower in the SAH plus DETA/NO plus KT5823 and SAH plus DETA/NO plus 40Gap27 groups than in the SAH plus ETA/NO group. The BAs showed significant vasodilation in the SAH plus DETA/NO and SAH plus 8-Br-cGMP groups. However, the vasodilation response of BAs was inhibited in the SAH plus DETA/NO plus KT5823 and SAH plus DETA-NO plus 40Gap27 groups. CONCLUSIONS: The NO-cGMP-PKG pathway alleviated cerebral vasospasm via Cx40 upregulation.


Assuntos
Conexinas/fisiologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Guanosina Monofosfato/metabolismo , Óxido Nítrico/fisiologia , Hemorragia Subaracnóidea/fisiopatologia , Vasoespasmo Intracraniano/fisiopatologia , Animais , Conexinas/metabolismo , Modelos Animais de Doenças , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Guanilil Ciclase Solúvel/metabolismo , Regulação para Cima/fisiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-31913684

RESUMO

Local skin heating to 42°C causes cutaneous thermal hyperemia largely via nitric oxide (NO) synthase (NOS)-related mechanisms. We assessed the hypothesis that ATP-sensitive K+ (KATP) channels interact with NOS to mediate cutaneous thermal hyperemia. In 13 young adults (6 women, 7 men), cutaneous vascular conductance (CVC) was measured at four intradermal microdialysis sites that were continuously perfused with 1) lactated Ringer solution (control), 2) 5 mM glibenclamide (KATP channel blocker), 3) 20 mM NG-nitro-l-arginine methyl ester (NOS inhibitor), or 4) a combination of KATP channel blocker and NOS inhibitor. Local skin heating to 42°C was administered at all four treatment sites to elicit cutaneous thermal hyperemia. Thirty minutes after the local heating, 1.25 mM pinacidil (KATP channel opener) and subsequently 25 mM sodium nitroprusside (NO donor) were administered to three of the four sites (each 25-30 min). The local heating-induced prolonged elevation in CVC was attenuated by glibenclamide (19%), but the transient initial peak was not. However, glibenclamide had no effect on the prolonged elevation in CVC in the presence of NOS inhibition. Pinacidil caused an elevation in CVC, but this response was abolished at the glibenclamide-treated skin site, demonstrating its effectiveness as a KATP channel blocker. The pinacidil-induced increase in CVC was unaffected by NOS inhibition, whereas the increase in CVC elicited by sodium nitroprusside was partly (15%) inhibited by glibenclamide. In summary, we showed an interactive effect of KATP channels and NOS for the plateau of cutaneous thermal hyperemia. This interplay may reflect a vascular smooth muscle cell KATP channel activation by NO.


Assuntos
Hiperemia/enzimologia , Canais KATP/metabolismo , Microcirculação , Microvasos/enzimologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Pele/irrigação sanguínea , Vasodilatação , Adulto , Velocidade do Fluxo Sanguíneo , Inibidores Enzimáticos/administração & dosagem , Feminino , Humanos , Hiperemia/etiologia , Hiperemia/fisiopatologia , Hipotermia Induzida , Ativação do Canal Iônico , Canais KATP/antagonistas & inibidores , Masculino , Microcirculação/efeitos dos fármacos , Microvasos/efeitos dos fármacos , Microvasos/fisiopatologia , Doadores de Óxido Nítrico/administração & dosagem , Óxido Nítrico Sintase/antagonistas & inibidores , Bloqueadores dos Canais de Potássio/administração & dosagem , Transdução de Sinais , Vasodilatação/efeitos dos fármacos , Vasodilatadores/administração & dosagem , Adulto Jovem
18.
Artigo em Inglês | MEDLINE | ID: mdl-31927272

RESUMO

In order to evaluate the genes involved in polyamines synthesis pathway and the role of nitric oxide synthase (NOS) and H2O2 in stomatal closure under drought stress, a research conducted with three irrigation levels (100, 50 and 25% field capacity) at 1, 3, 6 and 12 days on Rosa damascena Mill. HPLC and qPCR results showed that putrescine (Put) accumulation occurred at first day in both 50 and 25% of field capacity and then decreased the other days. Furthermore, Put accumulation in the indirect pathway (ADC, AIH and CPA) was more effective related to the direct pathway (ODC) under severe stress. Increased expression of genes involved in production of spermidine (Spd) and spermine (Spm) i.e., SAMDC, SPDS and SPMS correlated with the highest accumulation of Spd and Spm under 50% FC at 6 d and 25% FC at 12 d, respectively. Moreover, results showed that Put reduction simultaneously accumulated H2O2, which subsequently increased NOS expression suggesting a key signal for stomatal closure.


Assuntos
Secas , Óxido Nítrico Sintase , Estômatos de Plantas , Poliaminas , Rosa , Estresse Fisiológico , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Estômatos de Plantas/enzimologia , Estômatos de Plantas/genética , Poliaminas/metabolismo , Rosa/enzimologia , Rosa/genética , Espermidina/metabolismo , Espermina/metabolismo , Estresse Fisiológico/genética
19.
Parasitol Res ; 119(1): 333-337, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31788770

RESUMO

Chagas disease (CD) is a tropical zoonosis caused by the protozoan Trypanosoma cruzi. Severe autonomic dysfunction like reduced cardiac catecholamine-containing or acetylcholinesterase-positive innervation have been reported in CD. Renin-angiotensin system (RAS) seems to participate in the regulation of adrenal catecholamine secretion by adrenal medullary chromaffin cells, which might be dependent of nitric oxide (NO) pathways. To investigate the levels of RAS components in the adrenal gland during the acute infection with Y strain T. cruzi and in response to acute administration of an inhibitor of the enzyme NO synthase, L-NAME. Male Holtzman rats were inoculated intraperitoneally with Y strain T. cruzi and received L-NAME or tap water from one day before the infection until 13 or 17 days post-inoculation (dpi). The concentration of RAS molecules in the adrenal tissue was evaluated by ELISA immunoassay. Angiotensin converting enzyme 1 (ACE1) levels were significantly lower at 17 dpi when compared to 13 dpi. No significant differences were found compared with baseline, and no changes were detected in adrenal tissue levels of angiotensin converting enzyme 2 (ACE2), angiotensin II, or angiotensin-(1-7). Moreover, the treatment with L-NAME did not influence the levels of RAS components in adrenal tissue during the course of T. cruzi infection. We provided the first evidence that levels of RAS molecules change in the adrenal gland during acute phase of T. cruzi infection. Future studies are necessary to fully address the role of NO in RAS-associated adrenal gland function in CD.


Assuntos
Glândulas Suprarrenais/metabolismo , Doença de Chagas/metabolismo , Óxido Nítrico/metabolismo , Sistema Renina-Angiotensina/fisiologia , Trypanosoma cruzi/fisiologia , Animais , Modelos Animais de Doenças , Masculino , NG-Nitroarginina Metil Éster/administração & dosagem , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Peptidil Dipeptidase A/metabolismo , Ratos , Ratos Sprague-Dawley
20.
Mol Cell ; 77(1): 95-107.e5, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31628042

RESUMO

GTP cyclohydrolase I (GTPCH), 6-pyruvoyltetrahydropterin synthase (PTPS), and sepiapterin reductase (SR) are sequentially responsible for de novo synthesis of tetrahydrobiopterin (BH4), a known co-factor for nitric oxide synthase (NOS). The implication of BH4-biosynthesis process in tumorigenesis remains to be investigated. Here, we show that PTPS, which is highly expressed in early-stage colorectal cancer, is phosphorylated at Thr 58 by AMPK under hypoxia; this phosphorylation promotes PTPS binding to LTBP1 and subsequently drives iNOS-mediated LTBP1 S-nitrosylation through proximal-coupling BH4 production within the PTPS/iNOS/LTBP1 complex. In turn, LTBP1 S-nitrosylation results in proteasome-dependent LTBP1 protein degradation, revealing an inverse relationship between PTPS pT58 and LTBP1 stability. Physiologically, the repressive effect of PTPS on LTBP1 leads to impaired transforming growth factor ß (TGF-ß) secretion and thereby maintains tumor cell growth under hypoxia. Our findings illustrate a molecular mechanism underlying the regulation of LTBP1-TGF-ß signaling by the BH4-biosynthesis pathway and highlight the specific requirement of PTPS for tumor growth.


Assuntos
Proliferação de Células/fisiologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Hipóxia/metabolismo , Proteínas de Ligação a TGF-beta Latente/metabolismo , Fósforo-Oxigênio Liases/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Óxido Nítrico Sintase/metabolismo , Fosforilação/fisiologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/metabolismo
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