Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 683
Filter
1.
Rev. Assoc. Med. Bras. (1992) ; 66(8): 1128-1133, Aug. 2020. tab
Article in English | LILACS, SES-SP | ID: biblio-1136334

ABSTRACT

SUMMARY AIM The aim of this study was to examine the roles of nitric oxide (NOx), endothelial nitric oxide synthetase (eNOS), and asymmetric dimethylarginine (ADMA), which is the major endogenous inhibitor of nitric oxide synthases (NOS), in the pathophysiology of hemorrhoidal disease. METHODS This study included 54 patients with grades 3 and 4 internal hemorrhoidal disease and 54 patients without the disease who attended the General Surgery Clinic. NOx, eNOS, and ADMA levels were measured with the Enzyme-Linked ImmunoSorbent Assay (ELISA) method. RESULTS The patients had higher NO and eNOS levels and lower ADMA levels than the control subjects (p<0.001). A significant highly positive correlation was found between NO and eNOS (p<0.001). Nevertheless, there was a highly negative correlation between ADMA and NO-eNOS(p<0.001, p<0.001). CONCLUSION This preliminary study reveals that higher NOx and eNOS activities and lower ADMA levels in the rectal mucosa are observed in patients with hemorrhoidal disease than in those with normal rectal tissue. The imbalance between endothelium-derived relaxing factors, such as NO and endogenous competitive inhibitor of NOS, ADMA, may cause hemorrhoidal disease. Our study proposes that hemorrhoids display apparent vascular dilatation and present with bleeding or swelling. ADMA is an effective NOS inhibitor and may be a promising therapeutic option for hemorrhoidal disease.


RESUMO OBJETIVO O objetivo deste estudo foi examinar os papéis do óxido nítrico (NOx), do óxido nítrico sintetase endotelial (eNOS) e da dimetilarginina assimétrica (ADMA), que é o principal inibidor endógeno das óxido nítrico sintase (NOS) na fisiopatologia da doença hemorróida. MÉTODOS Este estudo incluiu 54 pacientes com doença hemorróida interna de grau 3 e 4 e 54 pacientes sem a doença que se inscreveram na Clínica Geral de Cirurgia. Os níveis de NOx, eNOS e ADMA foram medidos com o método de Ensaio Imuno absorvente ligado a enzima (ELISA). RESULTADOS Os pacientes têm níveis mais altos de NO e eNOS e níveis mais baixos de ADMA do que os indivíduos controle (p <0,001). Uma correlação altamente positiva significativa foi encontrada entre o NO-eNOS (p <0,001). No entanto, houve uma correlação negativa muito séria entre ADMA e NO-eNOS (p <0,001, p <0,001). CONCLUSÃO Este estudo preliminar revela que os pacientes com doença hemorróida têm atividades mais altas de NOx e eNOS e níveis mais baixos de ADMA na mucosa retal do que os pacientes com tecido retal normal. Desequilíbrio entre o fator relaxante derivado do endotélio, como; O NO e o inibidor competitivo endógeno da NOS, ADMA, podem causar doenças hemorróidas. Nosso estudo propõe que as hemorróidas exibam aparente dilatação vascular e apresentam sangramento ou inchaço, a ADMA é um inibidor eficaz da NOS e pode ser uma opção terapêutica promissora para a doença hemorróida.


Subject(s)
Humans , Hemorrhoids , Arginine/analogs & derivatives , Nitric Oxide Synthase Type III , Nitric Oxide
2.
Rev. bras. ciênc. mov ; 28(1): 78-91, jan.-mar., 2020. ilus, tab
Article in Portuguese | LILACS | ID: biblio-1102548

ABSTRACT

O objetivo do presente estudo foi avaliar o efeito da suplementação de arginina (ARG) sobre marcadores indiretos do dano muscular induzido pelo exercício (DMIE). Participaram do estudo 24 jovens universitários do sexo masculino, com experiência mínima de 1 ano em treinamento de força. Os indivíduos foram alocados em 2 grupos, em seguindo delineamento experimental duplo -cego: suplementado com 7g de arginina (ARG, n=12) ou suplementado com 7g de placebo (PLA, n =12 ). O suplemento foi oferecido 30 min antes da realização do protocolo de 10 séries de 10 repetições máximas (RMs) realizadas no supino. Foram aferidas a circunferência torácica, a dor muscular de in ício tardio (DMIT), por meio da escala visual analógica (EVA), e a carga do teste de uma repetição máxima (1 RM) em repouso, 24h, 48h e 72h após a sessão de treinamento (ST). Os resultados foram analisados utilizando teste de análise de variância ANOVA de dois fatores), seguido pelo teste de Bonferroni. A DMIT apresentou maior magnitude no PLA, em todos momentos avaliados após a ST, em comparação ao grupo ARG (p<0,01). Foi observado maior decréscimo da produção de força no grupo PLA, em 72h após a ST , comparado ao grupo ARG (p<0,05). A suplementação aguda de ARG parece ter atenuado a magnitude da DMIT e acelerado a recuperação da força...(AU)


The purpose of this study was to investigate the effect of arginine (ARG) supplementation o nindirect markers of exercise-induced muscle damage (EIMD). Twenty-four male graduate students, with a minimum of one year of experience in resistance training participated in the study . T he subject s were allocated in 2 groups in a double-blind experimental design: supplemented with 7 g o f argin ine (ARG, n=12) or supplemented with 7g of placebo (PLA, n=12). The dietary supplement was co n sum e d at 3 0 minutes prior to a protocol of 10 sets of 10 maximum repetitions performed in the bench press. Measurements of thoracic circumference, delayed onset muscle soreness (DOMS) using visual an alo gue scale (VAS), and one-repetition maximum (1RM) at rest, 24h, 48h and 72h after the training session (TS). The data were analyzed by ANOVA-two way, followed by the Bonferroni test. DOMS presented a reater magnitude for PLA, in all moments evaluated after TS, compared to the ARG group (p<0.01). There was a greater decrease in the strength for PLA, at 72h after TS, compared to ARG (p<0 .05 ). The acute ARG supplementation seems to attenuate the magnitude of DOMS and accelerate recovery of strength...(AU)


Subject(s)
Humans , Male , Arginine , Exercise , Analysis of Variance , Dietary Supplements , Richter Scale , Muscle Strength , Visual Analog Scale , Muscles , Measurements, Methods and Theories
4.
Article in Chinese | WPRIM | ID: wpr-878683

ABSTRACT

Kidney is one of the important organs of the body.With both excretory and endocrine functions,it plays a vital role in regulating the normal physiological state.As a precursor of the nitric oxide(NO)synthesis


Subject(s)
Animals , Arginine/physiology , Kidney/physiology , Muscle, Smooth, Vascular , Nitric Oxide/physiology , Rats , Receptors, Adrenergic, alpha-1/physiology , Renal Insufficiency/physiopathology , Signal Transduction , Vasoconstriction
5.
Chinese Medical Journal ; (24): 28-37, 2020.
Article in English | WPRIM | ID: wpr-878003

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is an extremely malignant disease, which has an extremely low survival rate of <9% in the United States. As a new hallmark of cancer, metabolism reprogramming exerts crucial impacts on PDAC development and progression. Notably, arginine metabolism is altered in PDAC cells and participates in vital signaling pathways. In addition, arginine and its metabolites including polyamine, creatine, agmatine, and nitric oxide regulate the proliferation, growth, autophagy, apoptosis, and metastasis of cancer cells. Due to the loss of argininosuccinate synthetase 1 (ASS1) expression, the key enzyme in arginine biosynthesis, arginine deprivation is regarded as a potential strategy for PDAC therapy. However, drug resistance develops during arginine depletion treatment, along with the re-expression of ASS1, metabolic dysfunction, and the appearance of anti-drug antibody. Additionally, arginase 1 exerts crucial roles in myeloid-derived suppressor cells, indicating its potential targeting by cancer immunotherapy. In this review, we introduce arginine metabolism and its impacts on PDAC cells. Also, we discuss the role of arginine metabolism in arginine deprivation therapy and immunotherapy for cancer.


Subject(s)
Arginine/metabolism , Argininosuccinate Synthase , Carcinoma, Pancreatic Ductal/drug therapy , Cell Line, Tumor , Humans , Pancreatic Neoplasms/drug therapy
6.
Braz. arch. biol. technol ; 63: e20190127, 2020. graf
Article in English | LILACS | ID: biblio-1132169

ABSTRACT

Abstract Bioprocess studies have been highlighted due to the importance of physiological processes and industrial applications of enzymes. The potential of peptidase production from Aspergillus section Flavi using different amino acids as a supplemental nitrogen source was investigated. A production profile revealed that amino acids had positive effects on peptidase production when compared to the control without amino acids. Optimal production (100 U/mL) was obtained with Arginine amino acid in 96 h of fermentation. Extracellular peptidase from Aspergillus section Flavi was identified in submerged bioprocesses by in situ activity. Biochemical studies revealed that the maximum activities of the enzyme extract were obtained at pH 6.5 and a temperature of 55°C. The inhibition by EDTA and PMSF suggests the presence of more than one peptidase while the Ni2+ and Cu2+ had a negative influence on the enzyme activity. When the crude extract was reversibly immobilized on ionic supports, DEAE-Agarose and MANAE-Agarose the derivative showed different profiles of thermal and pH stabilities. Hence, this study revealed the basic properties and biochemical characteristics that allowed the production improvement of this class of enzyme. Moreover, with known properties stabilization and immobilization process is required to further explore its biotechnological capacities.


Subject(s)
Peptide Hydrolases/biosynthesis , Aspergillus/enzymology , Amino Acids/administration & dosage , Arginine , Sepharose , Enzyme Inhibitors
7.
Electron. j. biotechnol ; 42: 49-55, Nov. 2019. tab, ilus, graf
Article in English | LILACS | ID: biblio-1087461

ABSTRACT

Background: Protein glutaminase specifically deamidates glutamine residue in protein and therefore significantly improves protein solubility and colloidal stability of protein solution. In order to improve its preparation efficiency, we exploited the possibility for its secretory expression mediated by twin-arginine translocation (Tat) pathway in Bacillus licheniformis. Results: The B. licheniformis genome-wide twin-arginine signal peptides were analyzed. Of which, eleven candidates were cloned for construction of expression vectors to mediate the expression of Chryseobacterium proteolyticum protein glutaminase (PGA). The signal peptide of GlmU was confirmed that it significantly mediated PGA secretion into media with the maximum activity of 0.16 U/ml in Bacillus subtilis WB600. A mutant GlmU-R, being replaced the third residue aspartic acid of GlmU twin-arginine signal peptide with arginine by site-directed mutagenesis, mediated the improved secretion of PGA with about 40% increased (0.23 U/ml). In B. licheniformis CBBD302, GlmU-R mediated PGA expression in active form with the maximum yield of 6.8 U/ml in a 25-l bioreactor. Conclusions: PGA can be produced and secreted efficiently in active form via Tat pathway of B. licheniformis, an alternative expression system for the industrial-scale production of PGA.


Subject(s)
Bacillus licheniformis/enzymology , Glutaminase/metabolism , Arginine , Plasmids , Prostaglandins A/chemistry , Bacillus subtilis , Protein Sorting Signals , Base Sequence , Mutagenesis, Site-Directed , Aspartic Acid , Escherichia coli , Bacillus licheniformis/genetics , Glutaminase/genetics
8.
Arq. bras. cardiol ; 113(2): 218-228, Aug. 2019. tab, graf
Article in English | LILACS | ID: biblio-1019401

ABSTRACT

Abstract Background: Studies have persuasively demonstrated that citrulline has a key role in the arginine-nitric oxide system, increasing nitric oxide bioavailability, an important mediator of peripheral vasodilation. Objective: To analyze the inter-individual post-exercise hypotension responsiveness following acute citrulline supplementation in hypertensives. Methods: Forty hypertensives were randomly assigned to one of the four experimental groups (control-placebo, control-citrulline, exercise-placebo, and exercise-citrulline). They ingested placebo or citrulline malate [CM] (6 grams). During the exercise session, individuals performed 40 minutes of walking/running on a treadmill at 60-70% of HR reserve. For the control session, the individuals remained seated at rest for 40 minutes. Office blood pressure (BP) was taken every 10 minutes until completing 60 minutes after the experimental session. The ambulatory BP device was programmed to take the readings every 20 minutes (awake time) and every 30 minutes (sleep time) over the course of 24 hours of monitoring. Statistical significance was defined as p < 0.05. Results: Unlike the other experimental groups, there were no "non-responders" in the exercise/citrulline (EC) for "awake" (systolic and diastolic BP) and "24 hours" (diastolic BP). The effect sizes were more consistent in the EC for systolic and diastolic ambulatorial BP response. The effects were "large" (> 0.8) for "awake", "asleep", and "24 hours" only in the EC for diastolic BP. Conclusion: CM supplementation can increase the post-exercise hypotensive effects in hypertensives. In addition, the prevalence of non-responders is lower when associated with aerobic exercise and CM supplementation.


Resumo Fundamento: Estudos demonstraram de maneira persuasiva que a citrulina tem um papel fundamental no sistema arginina-óxido nítrico, aumentando a biodisponibilidade do óxido nítrico, um importante mediador da vasodilatação periférica. Objetivo: Analisar a responsividade interindividual da hipotensão pós-exercício após suplementação aguda com citrulina em hipertensos. Métodos: Quarenta hipertensos foram aleatoriamente designados para um dos quatro grupos experimentais (controle-placebo, controle-citrulina, exercício-placebo e exercício-citrulina). Eles ingeriram placebo ou citrulina malato [CM] (6 gramas). Durante a sessão de exercício, os indivíduos realizaram 40 minutos de caminhada/corrida em esteira a 60-70% da FC de reserva. Para a sessão de controle, os indivíduos permaneceram sentados em repouso por 40 minutos. A medida da pressão arterial (PA) no consultório foi realizada a cada 10 minutos até completar 60 minutos após a sessão experimental. O dispositivo ambulatorial de PA foi programado para fazer as leituras a cada 20 minutos (tempo de vigília) e a cada 30 minutos (tempo de sono) ao longo de 24 horas de monitoramento. A significância estatística foi definida como p < 0,05. Resultados: Diferentemente de outros grupos experimentais, não houve "não respondedores" no exercício/citrulina (EC) para "acordado" (PA sistólica e diastólica) e "24 horas" (PA diastólica). Os tamanhos de efeito foram mais consistentes no EC para a resposta sistólica e diastólica da PA ambulatorial. Os efeitos foram "grandes" (> 0,8) para "acordado", "dormindo", e para "24 horas" apenas no EC para a PA diastólica. Conclusão: A suplementação com CM pode aumentar os efeitos hipotensivos pós-exercício em hipertensos. Além disso, a prevalência de "não respondedores" é menor quando associada ao exercício aeróbico e à suplementação com CM.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Vasodilator Agents/pharmacology , Blood Pressure/drug effects , Exercise/physiology , Citrulline/analogs & derivatives , Post-Exercise Hypotension/physiopathology , Hypertension/physiopathology , Malates/pharmacology , Arginine/metabolism , Reference Values , Time Factors , Placebo Effect , Anthropometry , Double-Blind Method , Analysis of Variance , Treatment Outcome , Citrulline/pharmacology , Statistics, Nonparametric , Exercise Test , Hypertension/therapy , Nitric Oxide/metabolism
9.
Article in English | WPRIM | ID: wpr-764506

ABSTRACT

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a maternally inherited mitochondrial disorder of which m.3243A>G is the most commonly associated mutation, resulting in an inability to meet the energy requirements of various organs. MELAS poses a diagnostic challenge owing to its multiple organ involvement and great clinical variability due to its heteroplasmic nature. We report three cases from a family who were initially misdiagnosed with myasthenia gravis or undiagnosed. Although there is no optimal consensus treatment approach for patients with MELAS because of the disease's heterogeneity, our 21-year-long therapy regimen of l-arginine, l-carnitine, and coenzyme Q10 supplementation combined with dietary management appeared to provide noticeable protection from the symptoms and complications. Prompt early diagnosis is important, as optimal multidisciplinary management and early intervention may improve outcomes.


Subject(s)
Acidosis, Lactic , Arginine , Carnitine , Consensus , DNA, Mitochondrial , Early Diagnosis , Early Intervention, Educational , Follow-Up Studies , Humans , MELAS Syndrome , Mitochondrial Diseases , Myasthenia Gravis , Population Characteristics
10.
Article in English | WPRIM | ID: wpr-777120

ABSTRACT

OBJECTIVE@#To examine the prognostic value of serum levels of asymmetric dimethylarginine (ADMA) in patients with stable coronary heart disease (CHD) thus explore a potential biomarker of "toxin syndrome" in CHD.@*METHODS@#In this prospective nested case-control study, 36 of 1,503 Chinese patients with stable CHD experienced at least 1 recurrent cardiovascular event (RCE) during 1-year follow-up. Serum levels of ADMA at the start of follow-up were compared between these 36 cases and 36 controls which matched to cases in terms of gender, age, history of hypertension, and myocardial infarction.@*RESULTS@#Based on the crude model, subjects in the 2 highest ADMA quartiles showed significantly higher risk of developing RCE than those in the lowest ADMA quartile [odds ratio (OR) 4.09, 95% confidence interval (CI) 1.01 to 16.58; OR 6.76, 95% CI 1.57 to 29.07]. This association was also observed in the case-mix model (OR 5.51, 95% CI 1.23 to 24.61; OR 7.83, 95% CI 1.68 to 36.41) and multivariable model (OR 6.64, 95% CI 1.40 to 31.49: OR 13.14, 95% CI 2.28 to 75.71) after adjusting for confounders. The multivariable model which combined ADMA and high-sensitivity C-reactive protein (hsCRP) showed better predictive power with areas under the receiver operator characteristic curves (0.779) than the model of either ADMA (0.694) or hsCRP (0.636).@*CONCLUSION@#Serum ADMA level may be a potential biomarker of "toxin syndrome" in CHD which shows favorable prognostic value in predicting 1-year RCE in patients with stable CHD. [The registration number is ChiCTR-PRNRC-07000012].


Subject(s)
Arginine , Blood , Biomarkers , Blood , Coronary Disease , Blood , Humans , Odds Ratio , ROC Curve , Recurrence , Risk Factors , Syndrome
11.
Laboratory Animal Research ; : 202-212, 2019.
Article in English | WPRIM | ID: wpr-786402

ABSTRACT

In this probe, at first we examined the best route and dosage of arginine administration on wound healing in an excisional wound model in rats. Next, we intend to assess the impact of photobiomodulation (PBM) and arginine, individually and together, on the wound healing. In the pilot study, an excisional wound was made in each of 24 rats. There were 4 groups. Group 1 was the control group. In groups 2 and 3, wounds were topically treated with arginine ointments (ARG.) 2% and 5%, respectively. In group 4, arginine was injected (ARG. INJ.,i.p.). In the main phase, in 24 new rats, an excisional wound was made. There were 4 groups: group 5 served as the control. Wounds in group 6 were topically treated with ARG 2%. Wounds in group 7 were subjected to PBM. Wounds in group 8 were treated with PBM+ARG. 2%. On day 15, wound area measurement, wound strength, and stereological examination were performed. In the pilot study, we found that the ARG 2% ointment significantly decreased wound area than ARG. 5%, ARG. INJ. and control groups, and significantly increased wound strength compared to the control and ARG.5% groups. In the main phase, a significant decrease of wound area in all treatment regimens was induced. PBM + ARG. 2% and PBM treatment regimens significantly improved wound strength and almost all stereological parameters, compared to the control and ARG. 2% groups. PBM + ARG. 2% induced anti-inflammatory and angiogenic activities, and hastened the wound healing process in an excisional wound model in rats.


Subject(s)
Animals , Arginine , Ointments , Pilot Projects , Rats , Wound Healing , Wounds and Injuries
12.
Article in English | WPRIM | ID: wpr-739331

ABSTRACT

Recovery from central nervous system (CNS) injury, such as stroke or spinal cord injury (SCI), largely depends on axonal regeneration, and the neuronal and glial cells plasticity in the lesioned tissue. The lesioned tissue following CNS injury forms a scar that is composed of astrocytes and mixed with connective tissues. At the glial scar, the regenerating axon forms dystrophic endbulbs which do not regenerate and grow beyond the glial scar without a suitable environment. Along with the astrocytes, microglia are also suspected of being involved in necrotic and apoptotic neuronal cell death and the early response to axonal damage in CNS injury. The inflammatory response, a major component of secondary injury and controlled by the microglia, plays a pivotal role in nerve injury and control the regenerative response. As a result, it is very important to control the glial cell function in order to assure the recovery of the CNS injury. Studies have suggested that agmatine, a L-arginine derived primary amine, is a potential modulator of glial cell function after CNS injuries. Agmatine was found to possess anti-inflammatory and neuroprotective characteristics that benefited the rehabilitation process following CNS injury. In this review, we will discuss the effect of agmatine on glial cells in the process of recovery after CNS injury.


Subject(s)
Agmatine , Arginine , Astrocytes , Axons , Cell Death , Central Nervous System , Cicatrix , Connective Tissue , Microglia , Neuroglia , Neurons , Plastics , Regeneration , Rehabilitation , Spinal Cord Injuries , Stroke
13.
HU rev ; 45(4): 441-451, 2019.
Article in Portuguese | LILACS | ID: biblio-1177336

ABSTRACT

Introdução: A lesão por pressão (LPP) é um dano localizado na pele e/ou no tecido mole subjacente que ocorre normalmente em pacientes acamados, com declínio do estado nutricional e da imunidade. Portanto, tem-se, o processo de cicatrização prejudicado e o uso de alguns imunomoduladores pode melhorar esse quadro, como a arginina. Objetivo: Identificar na literatura científica o efeito e o mecanismo de ação da arginina isolada ou associada na cicatrização de LPP. Material e Métodos: Revisão sistemática da literatura científica, com pesquisas nas bases de dados PubMed, Trip Data Base, Scielo, Science Direct e Scopus entre agosto de 2018 e abril de 2019, com recorte temporal de 2008 a 2018. Foram adotados os descritores e termos de pesquisa arginina, úlcera por pressão, cicatrização e tratamento. Resultados: A busca resultou em 11 artigos que atenderam aos critérios do presente estudo. Esses evidenciaram que a suplementação de arginina, isolada ou associada a nutrientes antioxidantes, possui resultados significativos no tratamento de LPP que levam a considerável diminuição do tempo de internação e dos custos hospitalares. Conclusão: O uso de arginina isolada ou associada a nutrientes antioxidantes têm efeitos promissores na cicatrização de LPP.


Introduction: Pressure ulcer (PU) is localized damage to the skin and/or underlying soft tissue that normally occurs in hospitalized patients with declining nutritional status and immunity. Therefore, one has, the process of impaired healing and use some immunomodulators may better this picture, such as arginine. Objective: To identify in the scientific literature the effect and mechanism of action of arginine alone or associated in the healing of PU. Material and Methods: Systematic review of the scientific literature, with searches in the databases PubMed, Trip Data Base, Scielo, Science Direct and Scopus between August 2018 and April 2019, with a temporal cut from 2008 to 2018. The following descriptors and terms were adopted arginine, pressure ulcer, healing and treatment. Results: The search resulted in 11 articles that met the criteria of the present study. These evidenced that arginine supplementation, alone or associated with antioxidant nutrients, has significant results in the treatment of LPP that lead to a considerable reduction in length of stay and hospital costs. Conclusion: The use of arginine alone or associated with antioxidant nutrients has promising effects on the healing of PU.


Subject(s)
Arginine , Arginine/adverse effects , Skin , Wound Healing , Pressure Ulcer , Bedridden Persons
14.
Rev. Col. Bras. Cir ; 46(6): e20192322, 2019. tab, graf
Article in Portuguese | LILACS | ID: biblio-1057185

ABSTRACT

RESUMO Objetivo: avaliar os efeitos da arginina na cicatrização da parede abdominal de ratos Wistar. Métodos: vinte ratos Wistar foram submetidos à laparotomia e separados em dois grupos (arginina e controle), que receberam tratamento diário por via intraperitoneal com arginina (300mg/kg/dia) e solução tampão fosfato em dose equivalente ao peso, respectivamente, durante cinco dias. No sétimo dia pós-operatório, coletaram-se amostras de sangue e da cicatriz da parede abdominal de ambos os grupos. Avaliaram-se o nível sérico de nitratos e nitritos, a evolução cicatricial pelas dosagens de hidroxiprolina tecidual, formação de tecido de granulação, determinação da porcentagem de colágeno maduro e imaturo, densidade de miofibroblastos e angiogênese. Empregaram-se os testes de ANOVA e t de Student com p=0,05 para as comparações entre os grupos. Resultados: não ocorreram diferenças significantes entre os grupos estudados para dosagens de nitratos e nitritos (p=0,9903), hidroxiprolina tecidual (p=0,1315) e densidade de miofibroblastos (p=0,0511). O grupo arginina apresentou maior densidade microvascular (p=0,0008), maior porcentagem de colágeno tipo I (p=0,0064) e melhora na formação do tecido de granulação, com melhores índices de proliferação angiofibroblástica (p=0,0007) e re-epitelização das bordas (p=0,0074). Conclusão: na avaliação cicatricial da parede abdominal de ratos Wistar sob tratamento com arginina, não houve alteração do nível sérico de nitratos e nitritos, da deposição de colágeno total e da densidade de miofibroblastos. Verificaram-se aumento da maturação de colágeno do tipo I, da densidade microvascular e melhora na formação do tecido de granulação cicatricial pelas melhores re-epitelização de bordas e proliferação angiofibroblástica.


ABSTRACT Objective: to evaluate the effects of arginine on abdominal wall healing in rats. Methods: we submitted 20 Wistar rats to laparotomy and divided them into two groups, arginine and control, which then received, respectively, daily intraperitoneal treatment with arginine (300mg/kg/day) and weight-equivalent phosphate buffered solution, during five days. On the seventh postoperative day, we collected blood and scar wall samples from both groups. We evaluated serum nitrate and nitrite levels, wound evolution by tissue hydroxyproline dosages, granulation tissue formation, percentage of mature and immature collagen, myofibroblast density and angiogenesis. We used the ANOVA and the Student's t tests with p=0.05 for comparisons between groups. Results: there were no significant differences between the groups studied for nitrate and nitrite (p=0.9903), tissue hydroxyproline (p=0.1315) and myofibroblast density (p=0.0511). The arginine group presented higher microvascular density (p=0.0008), higher percentage of type I collagen (p=0.0064) and improved granulation tissue formation, with better angiofibroblastic proliferation rates (p=0.0007) and wound edge reepithelization (p=0.0074). Conclusion: in the abdominal wall healing evaluation of Wistar rats under arginine treatment, there was no change in serum nitrate and nitrite levels, total collagen deposition and myofibroblast density. There was an increase in type I collagen maturation, microvascular density and improvement in scar granulation tissue formation by better edge reepithelization and angiofibroblastic proliferation.


Subject(s)
Animals , Rats , Arginine/pharmacology , Wound Healing/drug effects , Collagen/drug effects , Abdominal Wall/surgery , Collagen/metabolism , Rats, Wistar , Models, Animal , Abdominal Wall/pathology , Myofibroblasts/drug effects , Abdominal Injuries/drug therapy
15.
Experimental Neurobiology ; : 183-215, 2019.
Article in English | WPRIM | ID: wpr-739544

ABSTRACT

In the brain, a reduction in extracellular osmolality causes water-influx and swelling, which subsequently triggers Cl⁻- and osmolytes-efflux via volume-regulated anion channel (VRAC). Although LRRC8 family has been recently proposed as the pore-forming VRAC which is activated by low cytoplasmic ionic strength but not by swelling, the molecular identity of the pore-forming swelling-dependent VRAC (VRAC(swell)) remains unclear. Here we identify and characterize Tweety-homologs (TTYH1, TTYH2, TTYH3) as the major VRAC(swell) in astrocytes. Gene-silencing of all Ttyh1/2/3 eliminated hypo-osmotic-solution-induced Cl⁻ conductance (I(Cl,swell)) in cultured and hippocampal astrocytes. When heterologously expressed in HEK293T or CHO-K1 cells, each TTYH isoform showed a significant I(Cl,swell) with similar aquaporin-4 dependency, pharmacological properties and glutamate permeability as I(Cl,swell) observed in native astrocytes. Mutagenesis-based structure-activity analysis revealed that positively charged arginine residue at 165 in TTYH1 and 164 in TTYH2 is critical for the formation of the channel-pore. Our results demonstrate that TTYH family confers the bona fide VRAC(swell) in the brain.


Subject(s)
Arginine , Astrocytes , Brain , Cytoplasm , Glutamic Acid , Humans , Osmolar Concentration , Permeability
16.
Experimental Neurobiology ; : 85-103, 2019.
Article in English | WPRIM | ID: wpr-739528

ABSTRACT

Cell replacement therapy using neural progenitor cells (NPCs) following ischemic stroke is a promising potential therapeutic strategy, but lacks efficacy for human central nervous system (CNS) therapeutics. In a previous in vitro study, we reported that the overexpression of human arginine decarboxylase (ADC) genes by a retroviral plasmid vector promoted the neuronal differentiation of mouse NPCs. In the present study, we focused on the cellular mechanism underlying cell proliferation and differentiation following ischemic injury, and the therapeutic feasibility of NPCs overexpressing ADC genes (ADC-NPCs) following ischemic stroke. To mimic cerebral ischemia in vitro , we subjected the NPCs to oxygen-glucose deprivation (OGD). The overexpressing ADC-NPCs were differentiated by neural lineage, which was related to excessive intracellular calcium-mediated cell cycle arrest and phosphorylation in the ERK1/2, CREB, and STAT1 signaling cascade following ischemic injury. Moreover, the ADC-NPCs were able to resist mitochondrial membrane potential collapse in the increasingly excessive intracellular calcium environment. Subsequently, transplanted ADC-NPCs suppressed infarct volume, and promoted neural differentiation, synapse formation, and motor behavior performance in an in vivo tMCAO rat model. The results suggest that ADC-NPCs are potentially useful for cell replacement therapy following ischemic stroke.


Subject(s)
Animals , Arginine , Brain Ischemia , Calcium , Cell Cycle Checkpoints , Cell Proliferation , Central Nervous System , Humans , In Vitro Techniques , Membrane Potential, Mitochondrial , Mice , Models, Animal , Neurons , Phosphorylation , Plasmids , Stem Cells , Stroke , Synapses , Zidovudine
17.
Article in English | WPRIM | ID: wpr-763491

ABSTRACT

Colorectal cancer (CRC) is one of the major reasons of mortality in the worldwide. There is clear evidence that some amino acids such as arginine can improve CRC and its complications. Hence, in this systematic review we evaluated the association between arginine intake and CRC improvement. We searched the PubMed, Scopus, ISI Web of Science, Cochrane library, and Google Scholar databases by using proper keywords to find the relevant literatures, published to March 2019. Nine human studies of 523 screened articles were included in present systematic review. The majority of studies have found a positive association between consumption of arginine and CRC improvement. Increased inducible nitric oxide (NO) synthase expression and subsequently increasing the NO concentration in the tumor and/or serum, after arginine intake may be responsible for these protective effects. Also, arginine consumption may reduce cell proliferation in CRC and it can enhance immune function after remove the tumor. Although the benefits of arginine consumption in CRC patients were reported in previous trials, the finding need replication in well-designed studies before final conclusion.


Subject(s)
Amino Acids , Arginine , Cell Proliferation , Colorectal Neoplasms , Humans , Mortality , Nitric Oxide
18.
Yonsei Medical Journal ; : 366-375, 2018.
Article in English | WPRIM | ID: wpr-714674

ABSTRACT

PURPOSE: Vascular smooth muscle cell (VSMC) proliferation induced by native low-density lipoprotein (nLDL) stimulation is dependent on superoxide production from activated NADPH oxidase. The present study aimed to investigate whether the novel arginase inhibitor limonin could suppress nLDL-induced VSMC proliferation and to examine related mechanisms. MATERIALS AND METHODS: Isolated VSMCs from rat aortas were treated with nLDL, and cell proliferation was measured by WST-1 and BrdU assays. NADPH oxidase activation was evaluated by lucigenin-induced chemiluminescence, and phosphorylation of protein kinase C (PKC) βII and extracellular signal-regulated kinase (ERK) 1/2 was determined by western blot analysis. Mitochondrial reactive oxygen species (ROS) generation was assessed using MitoSOX-red, and intracellular L-arginine concentrations were determined by high-performance liquid chromatography (HPLC) in the presence or absence of limonin. RESULTS: Limonin inhibited arginase I and II activity in the uncompetitive mode, and prevented nLDL-induced VSMC proliferation in a p21Waf1/Cip1-dependent manner without affecting arginase protein levels. Limonin blocked PKCβII phosphorylation, but not ERK1/2 phosphorylation, and translocation of p47phox to the membrane was decreased, as was superoxide production in nLDL-stimulated VSMCs. Moreover, mitochondrial ROS generation was increased by nLDL stimulation and blocked by preincubation with limonin. Mitochondrial ROS production was responsible for the phosphorylation of PKCβII. HPLC analysis showed that arginase inhibition with limonin increases intracellular L-arginine concentrations, but decreases polyamine concentrations. L-Arginine treatment prevented PKCβII phosphorylation without affecting ERK1/2 phosphorylation. CONCLUSION: Increased L-arginine levels following limonin-dependent arginase inhibition prohibited NADPH oxidase activation in a PKCβII-dependent manner, and blocked nLDL-stimulated VSMC proliferation.


Subject(s)
Animals , Aorta , Arginase , Arginine , Blotting, Western , Bromodeoxyuridine , Cell Proliferation , Chromatography, High Pressure Liquid , Chromatography, Liquid , Lipoproteins , Luminescence , Membranes , Muscle, Smooth, Vascular , NADP , NADPH Oxidases , Phosphorylation , Phosphotransferases , Protein Kinase C , Rats , Reactive Oxygen Species , Superoxides
19.
Yonsei Medical Journal ; : 1138-1142, 2018.
Article in English | WPRIM | ID: wpr-718025

ABSTRACT

This study aimed to analyze the impact of sleep deprivation (SD) on cardiac, hemodynamic, and endothelial parameters and to determine whether these are sustained with increased periods of SD. The study included 60 healthy men (mean: age 31.2±6.3 years; body mass index 24.6±2.6 kg/m2). Hemodynamic parameters, parameters of myocardial contractility, spectral analysis of heart rate (HR) and blood pressure (BP) variability, and the sensitivity of arterial baroreflex function were evaluated. Biochemical tests were performed to assess L-arginine (L-Arg) and asymmetric dimethylarginine (ADMA) levels in reflection of endothelial nitric oxide synthase ability. Measurements of cardiovascular system parameters were obtained at 9 a.m. (baseline) on the first day of the study and 9 a.m. (24-h SD), 1 p.m. (28-h SD), and 5 p.m. (32-h SD) on the second day. Blood samples for evaluating biochemical parameters were obtained at baseline and after 24-h SD. ANOVA Friedman's test revealed a significant effect for time in relation to HR (χ²=26.04, df=5, p=0.000), systolic BP (χ²=35.98, df=5, p=0.000), diastolic BP (χ²=18.01, df=5, p=0.003), and mean BP (χ²=28.32, df=5, p=0.000). L-Arg and ADMA levels changed from 78.2±12.9 and 0.3±0.1 at baseline to 68.8±10.2 and 0.4±0.1 after 24-hr SD, respectively (p=0.001, p=0.004). SD in healthy men is associated with increases in BP, which appear to occur after 24 hours of SD and are maintained over increasing periods of SD. The observed hemodynamic changes may have resulted due to disordered vascular endothelial function, as reflected in alterations in L-Arg and ADMA levels.


Subject(s)
Arginine , Autonomic Nervous System , Baroreflex , Blood Pressure , Body Mass Index , Cardiovascular System , Heart Rate , Hemodynamics , Humans , Male , Multiple Endocrine Neoplasia Type 1 , Nitric Oxide Synthase Type III , Sleep Deprivation
20.
Braz. j. med. biol. res ; 51(5): e6693, 2018. graf
Article in English | LILACS | ID: biblio-889091

ABSTRACT

Testosterone synthesis within Leydig cells is a calcium-dependent process. Intracellular calcium levels are regulated by different processes including ATP-activated P2X purinergic receptors, T-type Ca2+ channels modulated by the luteinizing hormone, and intracellular calcium storages recruited by a calcium-induced calcium release mechanism. On the other hand, nitric oxide (NO) is reported to have an inhibitory role in testosterone production. Based on these observations, we investigated the interaction between the purinergic and nitrergic systems in Leydig cells of adult mice. For this purpose, we recorded ATP-evoked currents in isolated Leydig cells using the whole cell patch clamp technique after treatment with L-NAME (300 μM and 1 mM), L-arginine (10, 100, 300, and 500 μM), ODQ (300 μM), and 8-Br-cGMP (100 μM). Our results show that NO produced by Leydig cells in basal conditions is insufficient to change the ATP-evoked currents and that extra NO provided by adding 300 μM L-arginine positively modulates the current through a mechanism involving the NO/cGMP signaling pathway. Thus, we report an interaction between the nitrergic and purinergic systems in Leydig cells and suggest that Ca2+ entry via the purinergic receptors can be regulated by NO.


Subject(s)
Animals , Male , Mice , Adenosine Triphosphate/physiology , Receptors, Purinergic/metabolism , Leydig Cells/physiology , Nitric Oxide/physiology , Arginine/administration & dosage , Arginine/metabolism , Thionucleotides/administration & dosage , Thionucleotides/metabolism , Action Potentials , Cells, Cultured , Cyclic GMP/administration & dosage , Cyclic GMP/analogs & derivatives , Cyclic GMP/metabolism , Patch-Clamp Techniques , NG-Nitroarginine Methyl Ester/administration & dosage , NG-Nitroarginine Methyl Ester/metabolism , Nitric Oxide/biosynthesis
SELECTION OF CITATIONS
SEARCH DETAIL