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1.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199590

RESUMO

In living cells Reactive Oxygen Species (ROS) participate in intra- and inter-cellular signaling and all cells contain specific systems that guard redox homeostasis. These systems contain both enzymes which may produce ROS such as NADPH-dependent and other oxidases or nitric oxide synthases, and ROS-neutralizing enzymes such as catalase, peroxiredoxins, thioredoxins, thioredoxin reductases, glutathione reductases, and many others. Most of the genes coding for these enzymes contain sequences targeted by micro RNAs (miRNAs), which are components of RNA-induced silencing complexes and play important roles in inhibiting translation of their targeted messenger RNAs (mRNAs). In this review we describe miRNAs that directly target and can influence enzymes responsible for scavenging of ROS and their possible role in cellular redox homeostasis. Regulation of antioxidant enzymes aims to adjust cells to survive in unstable oxidative environments; however, sometimes seemingly paradoxical phenomena appear where oxidative stress induces an increase in the levels of miRNAs which target genes which are supposed to neutralize ROS and therefore would be expected to decrease antioxidant levels. Here we show examples of such cellular behaviors and discuss the possible roles of miRNAs in redox regulatory circuits and further cell responses to stress.


Assuntos
Antioxidantes/metabolismo , Homeostase/genética , MicroRNAs/genética , Estresse Oxidativo/genética , Glutationa Redutase/genética , Glutationa Redutase/metabolismo , Humanos , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Oxirredução , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
2.
Andrologia ; 53(7): e14098, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34051107

RESUMO

Up until today, there are still uncertainties regarding the occurrence of isoforms of the nitric oxide synthase (eNOS, nNOS) in the human prostate. While nNOS was exclusively seen in slender nerve fibres branching within the transition zone, eNOS was reported in glandular structures and also in small vessels interspersing the tissue. This study aimed to re-evaluate by means of light and electron microscopy (LM, EM), the distribution of eNOS and nNOS in the transition zone of the human prostate. Tissue specimens were obtained from 16 patients who underwent surgery for pelvic malignancies. Using specific antibodies in conjunction with advanced fixation and staining procedures, the occurrence of eNOS and nNOS was investigated. nNOS was detected in nerve fibres interspersing the tissue and was also seen in glandular structures. EM revealed that in glandular epithelial cells immunoreaction for nNOS was limited to the cytoplasmic compartment. Vascular endothelial cells of small vessels transversing glandular structures significantly stained for eNOS, while epithelial layers of prostatic glandules appeared free of eNOS. The results implicate that, in the prostate, nNOS is a mediator of stromal and glandular tissue function, and counteract the assumption of eNOS activity in glandular epithelial cells as a source of NO synthesis.


Assuntos
Células Endoteliais , Próstata , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Óxido Nítrico , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Próstata/metabolismo , Isoformas de Proteínas
3.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947005

RESUMO

Beneficial metabolic effects of inorganic nitrate (NO3-) and nitrite (NO2-) in type 2 diabetes mellitus (T2DM) have been documented in animal experiments; however, this is not the case for humans. Although it has remained an open question, the redox environment affecting the conversion of NO3- to NO2- and then to NO is suggested as a potential reason for this lost-in-translation. Ascorbic acid (AA) has a critical role in the gastric conversion of NO2- to NO following ingestion of NO3-. In contrast to AA-synthesizing species like rats, the lack of ability to synthesize AA and a lower AA body pool and plasma concentrations may partly explain why humans with T2DM do not benefit from NO3-/NO2- supplementation. Rats also have higher AA concentrations in their stomach tissue and gastric juice that can significantly potentiate gastric NO2--to-NO conversion. Here, we hypothesized that the lack of beneficial metabolic effects of inorganic NO3- in patients with T2DM may be at least in part attributed to species differences in AA metabolism and also abnormal metabolism of AA in patients with T2DM. If this hypothesis is proved to be correct, then patients with T2DM may need supplementation of AA to attain the beneficial metabolic effects of inorganic NO3- therapy.


Assuntos
Ácido Ascórbico/uso terapêutico , Diabetes Mellitus Tipo 2/metabolismo , Nitratos/farmacocinética , Oxirredutases do Álcool/deficiência , Animais , Arginina/metabolismo , Ácido Ascórbico/metabolismo , Ácido Ascórbico/farmacologia , Deficiência de Ácido Ascórbico/complicações , Deficiência de Ácido Ascórbico/tratamento farmacológico , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 2/complicações , Dieta , Suco Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Glucose/metabolismo , Cobaias , Homeostase , Humanos , Insulina/metabolismo , Camundongos , Modelos Animais , Nitratos/administração & dosagem , Nitratos/metabolismo , Nitratos/uso terapêutico , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Nitritos/metabolismo , Nitritos/farmacocinética , Necessidades Nutricionais , Oxirredução , Ratos , Especificidade da Espécie
4.
Int J Mol Sci ; 22(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33926146

RESUMO

Vascular dementia (VaD) is the second most common form of dementia worldwide. It is caused by cerebrovascular disease, and patients often show severe impairments of advanced cognitive abilities. Nitric oxide synthase (NOS) and nitric oxide (NO) play vital roles in the pathogenesis of VaD. The functions of NO are determined by its concentration and bioavailability, which are regulated by NOS activity. The activities of different NOS subtypes in the brain are partitioned. Pathologically, endothelial NOS is inactivated, which causes insufficient NO production and aggravates oxidative stress before inducing cerebrovascular endothelial dysfunction, while neuronal NOS is overactive and can produce excessive NO to cause neurotoxicity. Meanwhile, inflammation stimulates the massive expression of inducible NOS, which also produces excessive NO and then induces neuroinflammation. The vicious circle of these kinds of damage having impacts on each other finally leads to VaD. This review summarizes the roles of the NOS/NO pathway in the pathology of VaD and also proposes some potential therapeutic methods that target this pathway in the hope of inspiring novel ideas for VaD therapeutic approaches.


Assuntos
Demência Vascular/fisiopatologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Encéfalo/metabolismo , Transtornos Cerebrovasculares , Demência Vascular/metabolismo , Demência Vascular/terapia , Humanos , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/fisiologia , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/fisiologia , Transdução de Sinais
5.
Plant Sci ; 307: 110860, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33902845

RESUMO

Developing strategies to improve nitrogen (N) use efficiency (NUE) in plants is a challenge to reduce environmental problems linked to over-fertilization. The nitric oxide synthase (NOS) enzyme from the cyanobacteria Synechococcus PCC 7335 (SyNOS) has been recently identified and characterized. SyNOS catalyzes the conversion of arginine to citrulline and nitric oxide (NO), and then approximately 75 % of the produced NO is rapidly oxidized to nitrate by an unusual globin domain in the N-terminus of the enzyme. In this study, we assessed whether SyNOS expression in plants affects N metabolism, NUE and yield. Our results showed that SyNOS-expressing transgenic Arabidopsis plants have greater primary shoot length and shoot branching when grown under N-deficient conditions and higher seed production both under N-sufficient and N-deficient conditions. Moreover, transgenic plants showed significantly increased NUE in both N conditions. Although the uptake of N was not modified in the SyNOS lines, they showed an increase in the assimilation/remobilization of N under conditions of low N availability. In addition, SyNOS lines have greater N-deficiency tolerance compared to control plants. Our results support that SyNOS expression generates a positive effect on N metabolism and seed production in Arabidopsis, and it might be envisaged as a strategy to improve productivity in crops under adverse N environments.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Cianobactérias/genética , Cianobactérias/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Nitrogênio/metabolismo , Arginina/metabolismo , Óxido Nítrico Sintase/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
6.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33921984

RESUMO

Chronic pain syndromes are an important medical problem generated by various molecular, genetic, and pathophysiologic mechanisms. Back pain, neuropathic pain, and posttraumatic pain are the most important pathological processes associated with chronic pain in adults. Standard approaches to the treatment of them do not solve the problem of pain chronicity. This is the reason for the search for new personalized strategies for the prevention and treatment of chronic pain. The nitric oxide (NO) system can play one of the key roles in the development of peripheral pain and its chronicity. The purpose of the study is to review publications devoted to changes in the NO system in patients with peripheral chronical pain syndromes. We have carried out a search for the articles published in e-Library, PubMed, Oxford Press, Clinical Case, Springer, Elsevier, and Google Scholar databases. The search was carried out using keywords and their combinations. The role of NO and NO synthases (NOS) isoforms in peripheral pain development and chronicity was demonstrated primarily from animal models to humans. The most studied is the neuronal NOS (nNOS). The role of inducible NOS (iNOS) and endothelial NOS (eNOS) is still under investigation. Associative genetic studies have shown that single nucleotide variants (SNVs) of NOS1, NOS2, and NOS3 genes encoding nNOS, iNOS, and eNOS may be associated with acute and chronic peripheral pain. Prospects for the use of NOS inhibitors to modulate the effect of drugs used to treat peripheral pain syndrome are discussed. Associative genetic studies of SNVs NOS1, NOS2, and NOS3 genes are important for understanding genetic predictors of peripheral pain chronicity and development of new personalized pharmacotherapy strategies.


Assuntos
Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Manejo da Dor , Dor/metabolismo , Medicina de Precisão , Animais , Terapia Combinada , Suscetibilidade a Doenças , Predisposição Genética para Doença , Humanos , Dor/etiologia , Polimorfismo de Nucleotídeo Único , Medicina de Precisão/métodos
7.
Med Sci Monit ; 27: e930176, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33846282

RESUMO

BACKGROUND Intrahepatic cholestasis of pregnancy (ICP) is a condition specific to pregnancy, leading to increased fetal morbidity and mortality. Nitric oxide synthase (iNOS) may be a factor regulating the vasodilation of blood vessels, which are relevant to ischemic-hypoxic conditions. We aimed to explore the potential relationship between iNOS and ICP. MATERIAL AND METHODS A prospective, case-control study was conducted including 77 pregnant women with ICP and 80 healthy pregnant women as controls. Enzyme-linked immunosorbent assays were used to investigate maternal plasma iNOS levels. The placenta mRNA levels and cell-specific localization of iNOS were determined by quantitative polymerase chain reaction, western blotting, and immunohistochemical analysis. A multivariate linear regression model was used to identify the independent factors of serum total biliary acids (TAB) in ICP. RESULTS Compared with controls, the expression of iNOS was significantly lower in maternal serum and placentas with ICP (P<0.001). Maternal plasm iNOS levels were negatively correlated with TAB (r=-0.450, P<0.001), cholyglycine (r=-0.367, P<0.001), alanine aminotransferase (r=-.359, P<0.001), and aspartate aminotransferase (r=-0.329, P<0.001). iNOS level was an indicator for ICP by multivariate linear regression analysis (ß=-0.505, P<0.001). The ROC curve indicated the optimal cut-off level for iNOS was 2865.43 pg/mL (sensitivity, 85.71%; specificity, 63.75%). The ROC curve area for iNOS was 0.793 (95% CI 0.722-0.864). CONCLUSIONS iNOS plays an important role in poor fetoplacental vascular perfusion and adverse pregnancy outcomes. iNOS can provide complementary information in predicting the extent and severity of ICP.


Assuntos
Colestase Intra-Hepática/metabolismo , Óxido Nítrico Sintase/metabolismo , Placenta/metabolismo , Plasma/metabolismo , Complicações na Gravidez/metabolismo , Gravidez , Adulto , Estudos de Casos e Controles , Colestase Intra-Hepática/genética , Regulação para Baixo , Feminino , Idade Gestacional , Humanos , Óxido Nítrico Sintase/genética , Projetos Piloto , Complicações na Gravidez/genética , Resultado da Gravidez , Estudos Prospectivos , Adulto Jovem
8.
Int J Mol Sci ; 22(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919841

RESUMO

Sodium restriction is often recommended in heart failure (HF) to block symptomatic edema, despite limited evidence for benefit. However, a low-sodium diet (LSD) activates the classical renin-angiotensin-aldosterone system (RAAS), which may adversely affect HF progression and mortality in patients with dilated cardiomyopathy (DCM). We performed a randomized, blinded pre-clinical trial to compare the effects of a normal (human-equivalent) sodium diet and a LSD on HF progression in a normotensive model of DCM in mice that has translational relevance to human HF. The LSD reduced HF progression by suppressing the development of pleural effusions (p < 0.01), blocking pathological increases in systemic extracellular water (p < 0.001) and prolonging median survival (15%, p < 0.01). The LSD activated the classical RAAS by increasing plasma renin activity, angiotensin II and aldosterone levels. However, the LSD also significantly up-elevated the counter-regulatory RAAS by boosting plasma angiotensin converting enzyme 2 (ACE2) and angiotensin (1-7) levels, promoting nitric oxide bioavailability and stimulating 3'-5'-cyclic guanosine monophosphate (cGMP) production. Plasma HF biomarkers associated with poor outcomes, such as B-type natriuretic peptide and neprilysin were decreased by a LSD. Cardiac systolic function, blood pressure and renal function were not affected. Although a LSD activates the classical RAAS system, we conclude that the LSD delayed HF progression and mortality in experimental DCM, in part through protective stimulation of the counter-regulatory RAAS to increase plasma ACE2 and angiotensin (1-7) levels, nitric oxide bioavailability and cGMP production.


Assuntos
Angiotensina I/biossíntese , GMP Cíclico/metabolismo , Dieta Hipossódica , Edema/prevenção & controle , Insuficiência Cardíaca/complicações , Óxido Nítrico/metabolismo , Fragmentos de Peptídeos/biossíntese , Animais , Disponibilidade Biológica , Biomarcadores/sangue , Pressão Sanguínea , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/fisiopatologia , Edema/sangue , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/fisiopatologia , Rim/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Peptídeo Natriurético Encefálico/metabolismo , Óxido Nítrico/sangue , Óxido Nítrico Sintase/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Derrame Pleural , Sistema Renina-Angiotensina , Análise de Sobrevida , Sístole
9.
Int J Mol Sci ; 22(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799869

RESUMO

The possible cardioprotective effects of translocator protein (TSPO) modulation with its ligand 4'-Chlorodiazepam (4'-ClDzp) in isoprenaline (ISO)-induced rat myocardial infarction (MI) were evaluated, alone or in the presence of L-NAME. Wistar albino male rats (b.w. 200-250 g, age 6-8 weeks) were divided into 4 groups (10 per group, total number N = 40), and certain substances were applied: 1. ISO 85 mg/kg b.w. (twice), 2. ISO 85 mg/kg b.w. (twice) + L-NAME 50 mg/kg b.w., 3. ISO 85 mg/kg b.w. (twice) + 4'-ClDzp 0.5 mg/kg b.w., 4. ISO 85 mg/kg b.w. (twice) + 4'-ClDzp 0.5 mg/kg b.w. + L-NAME 50 mg/kg b.w. Blood and cardiac tissue were sampled for myocardial injury and other biochemical markers, cardiac oxidative stress, and for histopathological evaluation. The reduction of serum levels of high-sensitive cardiac troponin T hs cTnT and tumor necrosis factor alpha (TNF-α), then significantly decreased levels of serum homocysteine Hcy, urea, and creatinine, and decreased levels of myocardial injury enzymes activities superoxide dismutase (SOD) and glutathione peroxidase (GPx) as well as lower grades of cardiac ischemic changes were demonstrated in ISO-induced MI treated with 4'-ClDzp. It has been detected that co-treatment with 4'-ClDzp + L-NAME changed the number of registered parameters in comparison to 4'-ClDzp group, indicating that NO (nitric oxide) should be important in the effects of 4'-ClDzp.


Assuntos
Benzodiazepinonas/farmacologia , Proteínas de Transporte/metabolismo , Infarto do Miocárdio/prevenção & controle , NG-Nitroarginina Metil Éster/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Inibidores Enzimáticos/farmacologia , Glutationa Peroxidase/metabolismo , Homocisteína/sangue , Isoproterenol , Masculino , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/metabolismo , Miocárdio/enzimologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Ratos Wistar , Superóxido Dismutase/metabolismo , Troponina T/sangue , Fator de Necrose Tumoral alfa/sangue
10.
Int J Mol Sci ; 22(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802652

RESUMO

Red blood cells (RBCs) have been found to synthesize and release both nitric oxide (NO) and cyclic guanosine monophosphate (cGMP), contributing to systemic NO bioavailability. These RBC functions resulted impaired in chronic kidney disease (CKD). This study aimed to evaluate whether predialysis (conservative therapy, CT) and dialysis (peritoneal dialysis, PD; hemodialysis, HD) therapies used during CKD progression may differently affect NO-synthetic pathway in RBCs. Our data demonstrated that compared to PD, although endothelial-NO-synthase activation was similarly increased, HD and CT were associated to cGMP RBCs accumulation, caused by reduced activity of cGMP membrane transporter (MRP4). In parallel, plasma cGMP levels were increased by both CT and HD and they significantly decreased after hemodialysis, suggesting that this might be caused by reduced cGMP renal clearance. As conceivable, compared to healthy subjects, plasma nitrite levels were significantly reduced by HD and CT but not in patients on PD. Additionally, the increased carotid intima-media thickness (IMT) values did not reach the significance exclusively in patients on PD. Therefore, our results show that PD might better preserve the synthetic NO-pathway in CKD-erythrocytes. Whether this translates into a reduced development of uremic vascular complications requires further investigation.


Assuntos
Eritrócitos/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico/sangue , Diálise Peritoneal , Diálise Renal , Uremia/sangue , Idoso , GMP Cíclico/sangue , GMP Cíclico/metabolismo , Feminino , Humanos , Falência Renal Crônica/sangue , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Óxido Nítrico Sintase/metabolismo , Nitritos/sangue , Nitrosação , Fosforilação
11.
Mem Inst Oswaldo Cruz ; 116: e200417, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729328

RESUMO

BACKGROUND: Toxoplasma gondii causes toxoplasmosis and is controlled by activated macrophages. However, infection of macrophages by tachyzoites induces TGF-ß signaling (TGF-s) inhibiting nitric oxide (NO) production. NO inhibition may be a general escape mechanism of distinct T. gondii strains. OBJECTIVES: To evaluate in activated macrophages the capacity of T. gondii strains of different virulence and genetics (RH, type I; ME-49, type II; VEG, type III; P-Br, recombinant) to evade the NO microbicidal defense system and determine LC3 loading to the parasitophorous vacuole. METHODS: Activated peritoneal macrophages were infected with the different T. gondii strains, NO-production was evaluated by the Griess reagent, and inducible nitric oxide synthase expression, TGF-s, and LC3 localisation assayed by immunofluorescence. FINDINGS: Only RH persisted in macrophages, while VEG was more resistant than P-Br and ME-49. All strains induced TGF-s, degradation of inducible nitric oxide synthase, and NO-production inhibition from 2 to 24 h of infection, but only RH sustained these alterations for 48 h. By 24 h of infection, TGF-s lowered in macrophages infected by ME-49, and P-Br, and NO-production recovered, while VEG sustained TGF-s and NO-production inhibition longer. LC3 loading to parasitophorous vacuole was strain-dependent: higher for ME-49, P-Br and VEG, lower for RH. All strains inhibited NO-production, but only RH sustained this effect probably because it persisted in macrophages due to additional evasive mechanisms as lower LC3 loading to parasitophorous vacuole. MAIN CONCLUSIONS: These results support that T. gondii can escape the NO microbicidal defense system at the initial phase of the infection, but only the virulent strain sustain this evasion mechanism.


Assuntos
Macrófagos Peritoneais/parasitologia , Macrófagos/parasitologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/biossíntese , Toxoplasma/fisiologia , Animais , Macrófagos/metabolismo , Camundongos , Toxoplasmose Animal/parasitologia
12.
Life Sci ; 272: 119223, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33610574

RESUMO

AIMS: Hypertension underlies endothelial dysfunction, and activation of vasorelaxation signaling with low dependence on nitric oxide (NO) represents a good alternative for vascular modulation. C-type natriuretic peptide (CNP) causes relaxation by increasing cyclic guanosine 3',5'-monophosphate (cGMP) or Gi-protein activation through its natriuretic peptide receptor-B or -C, respectively. We have hypothesized that CNP could exerts its effects and could overcome endothelial dysfunction in two kidney-one clip (2K-1C) hypertensive rat aorta. Here, we investigate the intracellular signaling involved in CNP effects in hypertension. MATERIALS AND METHODS: The 2K-1C hypertension was induced in male Wistar rats (200 g). CNP-induced vascular relaxation and cGMP production were investigated in rat thoracic aortas. The natriuretic peptide receptor-B and -C localization was evaluated by immunofluorescence. Calcium mobilization was assessed in endothelial cells from rat aortas. KEY FINDINGS: CNP induced similar relaxation in normotensive and 2K-1C hypertensive rat aortas, which increased after endothelium removal. CNP-induced relaxation involved natriuretic peptide receptor-B and -C activation in 2K-1C rats. Nitric oxide synthase (NOS) and soluble guanylyl cyclase (sGC) counter-regulated CNP-particulate GC (pGC) activation in aortas. CNP reduced endothelial calcium and increased cGMP production, which was lower in 2K-1C. CNP-induced cGMP-dependent protein kinase (PKG) and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) activation was impaired in 2K-1C rat aorta. SIGNIFICANCE: Our results indicated CNP triggered relaxation through its natriuretic peptide receptor-B and -C in 2K-1C rat aortas, and that CNP-induced relaxation overcomes endothelial dysfunction in hypertension. In addition, NOS and sGC activities counter-regulate CNP-pGC activation to induce vascular relaxation.


Assuntos
Peptídeo Natriurético Tipo C/farmacologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Vasodilatação/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , GMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Guanilato Ciclase/metabolismo , Hipertensão/fisiopatologia , Rim/metabolismo , Masculino , Peptídeo Natriurético Tipo C/metabolismo , Peptídeos Natriuréticos/metabolismo , Peptídeos Natriuréticos/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Wistar , Instrumentos Cirúrgicos , Vasodilatação/fisiologia
13.
J Toxicol Sci ; 46(1): 1-10, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33408296

RESUMO

Bisphenol A (BPA) is an endocrine-disrupting chemical used in polycarbonate and epoxy resins. Previously, we found that BPA stabilized the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) by inducing Ca2+ efflux into the cytosol, followed by nitric oxide synthase activation, resulting in the enhanced nitrosylation of Keap1, which is a negative regulator of Nrf2. However, the mechanisms behind the stimulation of Ca2+ efflux by BPA remain unknown. In the present study, we found that BPA stimulated Ca2+ efflux into the cytosol from the ER, but not from outside of cells through the plasma membrane in Hep3B cells. Ca2+ efflux and Nrf2 stabilization by BPA were inhibited by an inhibitor of the inositol 1,4,5-trisphosphate (IP3) receptor, 2-aminoethoxydiphenylborane, in the endoplasmic reticulum. IP3 is produced by activation of phospholipase C (PLC) from a membrane lipid, phosphatidylinositol 4,5-bisphosphate (PIP2). The induction of Nrf2 by BPA was not inhibited by a PLC inhibitor, U-73122, suggesting that BPA does not induce the production of IP3 via PLC activation. We found that BPA bound directly to the IP3 binding core domain of the IP3 receptor, and BPA competed with IP3 on this site. In addition, overexpression of this domain of the IP3 receptor in Hep3B cells inhibited the stabilization of Nrf2 by BPA. These results clarified that the IP3 receptor is a new target of BPA, and that BPA induces Ca2+ efflux from the endoplasmic reticulum via activation of the IP3 receptor.


Assuntos
Compostos Benzidrílicos/efeitos adversos , Cálcio/metabolismo , Disruptores Endócrinos/efeitos adversos , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fenóis/efeitos adversos , Células Cultivadas , Citosol/metabolismo , Retículo Endoplasmático/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Óxido Nítrico Sintase/metabolismo
14.
PLoS One ; 16(1): e0245974, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33497400

RESUMO

Autonomic neurons innervating uterine horn is probably the only nerve cell population capable of periodical physiological degeneration and regeneration. One of the main sources of innervation of the uterus is paracervical ganglion (PCG). PCG is a unique structure of the autonomic nervous system. It contains components of both the sympathetic and parasympathetic nervous system. The present study examines the response of neurons of PCG innervating uterine horn to axotomy caused by partial hysterectomy in the domestic pig animal model. The study was performed using a neuronal retrograde tracing and double immunofluorescent staining for tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DßH), choline acetyltransferase (ChAT), vesicular acetylcholine transporter (VAChT), neuronal nictric oxide synthase (nNOS), galanin, neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), pituitary adenylate cyclase-activating peptide (PACAP), somatostatin and substance P (SP). Our study showed that virtually all neurons of the porcine PCG innervating uterine horn are adrenergic and we did not confirm that PCG is the source of cholinergic fibers innervating uterine horn of the pig. After axotomy there was a decrease in expression of catecholamine-synthesizing enzymes (TH, DßH) and a strong increase in the galanin expression. The increase of the number of NPY-IR neurons in the ganglia after axotomy was observed. There were no changes in the expression of other studied substances in the PCG neurons innervating the uterine horn, what was often found in rodents studies. This indicates that neurons can respond to damage in a species-specific way.


Assuntos
Gânglios Espinais/metabolismo , Histerectomia/métodos , Neurônios/metabolismo , Útero/inervação , Animais , Colina O-Acetiltransferase/metabolismo , Dopamina beta-Hidroxilase/metabolismo , Feminino , Óxido Nítrico Sintase/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Somatostatina/metabolismo , Substância P/metabolismo , Suínos , Tirosina 3-Mono-Oxigenase/metabolismo , Útero/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Proteínas Vesiculares de Transporte de Acetilcolina/metabolismo
15.
Invest Ophthalmol Vis Sci ; 62(1): 10, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33410914

RESUMO

Purpose: Intrinsically photosensitive retinal ganglion cells (ipRGCs) signal not only centrally to non-image-forming visual centers of the brain but also intraretinally to amacrine interneurons through gap junction electrical coupling, potentially modulating image-forming retinal processing. We aimed to determine (1) which ipRGC types couple with amacrine cells, (2) the neuromodulator contents of ipRGC-coupled amacrine cells, and (3) whether connexin36 (Cx36) contributes to ipRGC-amacrine coupling. Methods: Gap junction-permeable Neurobiotin tracer was injected into green fluorescent protein (GFP)-labeled ipRGCs in Opn4Cre/+; Z/EG mice to stain coupled amacrine cells, and immunohistochemistry was performed to reveal the neuromodulator contents of the Neurobiotin-stained amacrine cells. We also created Opn4Cre/+; Cx36flox/flox; Z/EG mice to knock out Cx36 in GFP-labeled ipRGCs and looked for changes in the number of ipRGC-coupled amacrine cells. Results: Seventy-three percent of ipRGCs, including all six types (M1-M6), were tracer-coupled with amacrine somas 5.7 to 16.5 µm in diameter but not with ganglion cells. Ninety-two percent of the ipRGC-coupled somas were in the ganglion cell layer and the rest in the inner nuclear layer. Some ipRGC-coupled amacrine cells were found to accumulate serotonin or to contain nitric oxide synthase or neuropeptide Y. Knocking out Cx36 in M2 and M4 dramatically reduced the number of coupled somas. Conclusions: Heterologous gap junction coupling with amacrine cells is widespread across mouse ipRGC types. ipRGC-coupled amacrine cells probably comprise multiple morphologic types and use multiple neuromodulators, suggesting that gap junctional ipRGC-to-amacrine signaling likely exerts diverse modulatory effects on retinal physiology. ipRGC-amacrine coupling is mediated partly, but not solely, by Cx36.


Assuntos
Células Amácrinas/citologia , Conexinas/metabolismo , Junções Comunicantes/fisiologia , Neuropeptídeo Y/metabolismo , Óxido Nítrico Sintase/metabolismo , Células Ganglionares da Retina/citologia , Serotonina/metabolismo , Células Amácrinas/metabolismo , Animais , Biotina/administração & dosagem , Biotina/análogos & derivados , Comunicação Celular/fisiologia , Feminino , Proteínas de Fluorescência Verde/administração & dosagem , Substâncias Luminescentes/administração & dosagem , Masculino , Camundongos , Camundongos Knockout , Isoformas de Proteínas , Células Ganglionares da Retina/metabolismo , Opsinas de Bastonetes
16.
Am J Physiol Regul Integr Comp Physiol ; 320(5): R588-R610, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33501888

RESUMO

Whether hypoxic acclimation influences nitric oxide (NO)-mediated control of fish cardiac function is not known. Thus, we measured the function/performance of myocardial strips from normoxic- and hypoxic-acclimated (40% air saturation; ∼8 kPa O2) trout at several frequencies (20-80 contractions·min-1) and two muscle strain amplitudes (8% and 14%) when exposed to increasing concentrations of the NO donor sodium nitroprusside (SNP) (10-9 to 10-4 M). Further, we examined the influence of 1) nitric oxide synthase (NOS) produced NO [by blocking NOS with 10-4 M NG-monomethyl-l-arginine (l-NMMA)] and 2) soluble guanylyl cyclase mediated, NOS-independent, NO effects (i.e., after blockade with 10-4 M ODQ), on myocardial contractility. Hypoxic acclimation increased twitch duration by 8%-10% and decreased mass-specific net power by ∼35%. However, hypoxic acclimation only had minor impacts on the effects of SNP and the two blockers on myocardial function. The most surprising finding of the current study was the degree to which contraction frequency and strain amplitude influenced NO-mediated effects on myocardial power. For example, at 8% strain, 10-4 SNP resulted in a decrease in net power of ∼30% at 20 min-1 but an increase of ∼20% at 80 min-1, and this effect was magnified at 14% strain. This research suggests that hypoxic acclimation has only minor effects on NO-mediated myocardial contractility in salmonids, is the first to report the high frequency- and strain-dependent nature of NO effects on myocardial contractility in fishes, and supports previous work showing that NO effects on the heart (myocardium) are finely tuned spatiotemporally.


Assuntos
Aclimatação , Hipóxia/metabolismo , Contração Miocárdica , Miocárdio/metabolismo , Óxido Nítrico/metabolismo , Oncorhynchus mykiss/metabolismo , Animais , Inibidores Enzimáticos/farmacologia , Proteínas de Peixes/antagonistas & inibidores , Proteínas de Peixes/metabolismo , Hipóxia/fisiopatologia , Cinética , Contração Miocárdica/efeitos dos fármacos , Doadores de Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Guanilil Ciclase Solúvel/antagonistas & inibidores , Guanilil Ciclase Solúvel/metabolismo
17.
Am J Physiol Heart Circ Physiol ; 320(2): H668-H678, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33306447

RESUMO

Passive leg movement (PLM) evokes a robust and predominantly nitric oxide (NO)-mediated increase in blood flow that declines with age and disease. Consequently, PLM is becoming increasingly accepted as a sensitive assessment of endothelium-mediated vascular function. However, a substantial PLM-induced hyperemic response is still evoked despite nitric oxide synthase (NOS) inhibition. Therefore, in nine young healthy men (25 ± 4 yr), this investigation aimed to determine whether the combination of two potent endothelium-dependent vasodilators, specifically prostaglandin (PG) and endothelium-derived hyperpolarizing factor (EDHF), account for the remaining hyperemic response to the two variants of PLM, PLM (60 movements) and single PLM (sPLM, 1 movement), when NOS is inhibited. The leg blood flow (LBF, Doppler ultrasound) response to PLM and sPLM following the intra-arterial infusion of NG-monomethyl-l-arginine (l-NMMA), to inhibit NOS, was compared to the combined inhibition of NOS, cyclooxygenase (COX), and cytochrome P-450 (CYP450) by l-NMMA, ketorolac tromethamine (KET), and fluconazole (FLUC), respectively. NOS inhibition attenuated the overall LBF [area under the curve (LBFAUC)] response to both PLM (control: 456 ± 194, l-NMMA: 168 ± 127 mL, P < 0.01) and sPLM (control: 185 ± 171, l-NMMA: 62 ± 31 mL, P = 0.03). The combined inhibition of NOS, COX, and CYP450 (i.e., l-NMMA+KET+FLUC) did not further attenuate the hyperemic responses to PLM (LBFAUC: 271 ± 97 mL, P > 0.05) or sPLM (LBFAUC: 72 ± 45 mL, P > 0.05). Therefore, PG and EDHF do not collectively contribute to the non-NOS-derived NO-mediated, endothelium-dependent hyperemic response to either PLM or sPLM in healthy young men. These findings add to the mounting evidence and understanding of the vasodilatory pathways assessed by the PLM and sPLM vascular function tests.NEW & NOTEWORTHY Passive leg movement (PLM) evokes a highly nitric oxide (NO)-mediated hyperemic response and may provide a novel evaluation of vascular function. The contributions of endothelium-dependent vasodilatory pathways, beyond NO and including prostaglandins and endothelium-derived hyperpolarizing factor, to the PLM-induced hyperemic response to PLM have not been evaluated. With intra-arterial drug infusion, the combined inhibition of nitric oxide synthase (NOS), cyclooxygenase, and cytochrome P-450 (CYP450) pathways did not further diminish the hyperemic response to PLM compared with NOS inhibition alone.


Assuntos
Endotélio Vascular/fisiologia , Hiperemia , Movimento , Contração Muscular , Músculo Esquelético/irrigação sanguínea , Óxido Nítrico/metabolismo , Vasodilatação , Adulto , Fatores Biológicos/metabolismo , Velocidade do Fluxo Sanguíneo , Inibidores de Ciclo-Oxigenase/administração & dosagem , Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Endotélio Vascular/metabolismo , Voluntários Saudáveis , Humanos , Infusões Intra-Arteriais , Perna (Membro) , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Prostaglandinas/metabolismo , Fluxo Sanguíneo Regional , Transdução de Sinais , Fatores de Tempo , Adulto Jovem
18.
Handb Exp Pharmacol ; 264: 169-204, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32797331

RESUMO

The 1998 Nobel Prize in Medicine and Physiology for the discovery of nitric oxide, a nitrogen containing reactive oxygen species (also termed reactive nitrogen or reactive nitrogen/oxygen species) stirred great hopes. Clinical applications, however, have so far pertained exclusively to the downstream signaling of cGMP enhancing drugs such as phosphodiesterase inhibitors and soluble guanylate cyclase stimulators. All clinical attempts, so far, to inhibit NOS have failed even though preclinical models were strikingly positive and clinical biomarkers correlated perfectly. This rather casts doubt on our current way of target identification in drug discovery in general and our way of patient stratification based on correlating but not causal biomarkers or symptoms. The opposite, NO donors, nitrite and enhancing NO synthesis by eNOS/NOS3 recoupling in situations of NO deficiency, are rapidly declining in clinical relevance or hold promise but need yet to enter formal therapeutic guidelines, respectively. Nevertheless, NOS inhibition in situations of NO overproduction often jointly with enhanced superoxide (or hydrogen peroxide production) still holds promise, but most likely only in acute conditions such as neurotrauma (Stover et al., J Neurotrauma 31(19):1599-1606, 2014) and stroke (Kleinschnitz et al., J Cereb Blood Flow Metab 1508-1512, 2016; Casas et al., Proc Natl Acad Sci U S A 116(14):7129-7136, 2019). Conversely, in chronic conditions, long-term inhibition of NOS might be too risky because of off-target effects on eNOS/NOS3 in particular for patients with cardiovascular risks or metabolic and renal diseases. Nitric oxide synthases (NOS) and their role in health (green) and disease (red). Only neuronal/type 1 NOS (NOS1) has a high degree of clinical validation and is in late stage development for traumatic brain injury, followed by a phase II safety/efficacy trial in ischemic stroke. The pathophysiology of NOS1 (Kleinschnitz et al., J Cereb Blood Flow Metab 1508-1512, 2016) is likely to be related to parallel superoxide or hydrogen peroxide formation (Kleinschnitz et al., J Cereb Blood Flow Metab 1508-1512, 2016; Casas et al., Proc Natl Acad Sci U S A 114(46):12315-12320, 2017; Casas et al., Proc Natl Acad Sci U S A 116(14):7129-7136, 2019) leading to peroxynitrite and protein nitration, etc. Endothelial/type 3 NOS (NOS3) is considered protective only and its inhibition should be avoided. The preclinical evidence for a role of high-output inducible/type 2 NOS (NOS2) isoform in sepsis, asthma, rheumatic arthritis, etc. was high, but all clinical development trials in these indications were neutral despite target engagement being validated. This casts doubt on the role of NOS2 in humans in health and disease (hence the neutral, black coloring).


Assuntos
Óxido Nítrico Sintase Tipo III , Óxido Nítrico Sintase , GMP Cíclico , Humanos , Óxido Nítrico , Óxido Nítrico Sintase/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais
19.
J Exp Bot ; 72(3): 781-792, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32910824

RESUMO

Nitric oxide (NO) was the first identified gaseous messenger and is now well established as a major ubiquitous signalling molecule. The rapid development of our understanding of NO biology in embryophytes came with the partial characterization of the pathways underlying its production and with the decrypting of signalling networks mediating its effects. Notably, the identification of proteins regulated by NO through nitrosation greatly enhanced our perception of NO functions. In comparison, the role of NO in algae has been less investigated. Yet, studies in Chlamydomonas reinhardtii have produced key insights into NO production through the identification of NO-forming nitrite reductase and of S-nitrosated proteins. More intriguingly, in contrast to embryophytes, a few algal species possess a conserved nitric oxide synthase, the main enzyme catalysing NO synthesis in metazoans. This latter finding paves the way for a deeper characterization of novel members of the NO synthase family. Nevertheless, the typical NO-cyclic GMP signalling module transducing NO effects in metazoans is not conserved in algae, nor in embryophytes, highlighting a divergent acquisition of NO signalling between the green and the animal lineages.


Assuntos
Clorófitas/metabolismo , Óxido Nítrico Sintase , Óxido Nítrico , GMP Cíclico , Óxido Nítrico Sintase/metabolismo , Nitritos , Transdução de Sinais
20.
Science ; 371(6526)2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33273062

RESUMO

Here we describe mechanistically distinct enzymes (a kinase, a guanosine triphosphatase, and a ubiquitin protein hydrolase) that function in disparate biochemical pathways and can also act in concert to mediate a series of redox reactions. Each enzyme manifests a second, noncanonical function-transnitrosylation-that triggers a pathological biochemical cascade in mouse models and in humans with Alzheimer's disease (AD). The resulting series of transnitrosylation reactions contributes to synapse loss, the major pathological correlate to cognitive decline in AD. We conclude that enzymes with distinct primary reaction mechanisms can form a completely separate network for aberrant transnitrosylation. This network operates in the postreproductive period, so natural selection against such abnormal activity may be decreased.


Assuntos
Doença de Alzheimer/enzimologia , Quinase 5 Dependente de Ciclina/metabolismo , Dinaminas/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Sinapses/enzimologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Cisteína/genética , Cisteína/metabolismo , Modelos Animais de Doenças , Células HEK293 , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Nitroarginina/farmacologia , Oxirredução , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Sinapses/patologia , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
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