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1.
Int Heart J ; 61(5): 984-992, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32921665

RESUMO

Uric acid is generated with reactive oxygen species via xanthine oxidase (XO), and hyperuricemia, which is identified as the excess of uric acid in the blood, has been associated with vascular endothelial dysfunction. However, the effects of urate-lowering medicines on endothelial function have not been fully elucidated. Thus this study determined and compared the effects of benzbromarone (urate transporter 1 inhibitor) and febuxostat (XO inhibitor) on endothelial function.This randomized, cross-over, open-label study initially recruited 30 patients with hyperuricemia. They were divided into two groups, treated initially with benzbromarone or febuxostat for three months and then were switched for the next three months. Endothelial function was defined as reactive hyperemia indexes (RHI) determined using Endo-PAT 2000 before and at three and six months after medication using the two agents. Blood levels of asymmetric dimethylarginine (ADMA) and high-molecular-weight (HMW) adiponectin were also compared. We finally analyzed data from 24 patients whose endothelial function was assessed as described above.Our findings show that levels of uric acid significantly decreased, whereas those of HMW adiponectin and the RHI have significantly increased after treatment with benzbromarone. Meanwhile, in patients administered with febuxostat, uric acid levels tended to decrease and RHI significantly decreased. Neither of the two agents altered ADMA levels. The changes in RHI (P = 0.026) and HMW adiponectin levels (P = 0.001) were found to be significantly greater in patients treated with benzbromarone than febuxostat. Changes in the levels of HMW adiponectin and of uric acid were significantly correlated (r = -0.424, P = 0.039).Benzbromarone has increased adiponectin besides reducing uric acid levels, and thus, this might confer more benefits on endothelial function than febuxostat.


Assuntos
Benzobromarona/uso terapêutico , Endotélio Vascular/fisiopatologia , Febuxostat/uso terapêutico , Hiperemia/fisiopatologia , Hiperuricemia/tratamento farmacológico , Uricosúricos/uso terapêutico , Adiponectina/sangue , Idoso , Arginina/análogos & derivados , Arginina/sangue , Estudos Cross-Over , Feminino , Supressores da Gota/uso terapêutico , Humanos , Hiperuricemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Proteínas de Transporte de Cátions Orgânicos/antagonistas & inibidores , Resultado do Tratamento , Ácido Úrico/sangue , Xantina Oxidase/antagonistas & inibidores
2.
Rev Assoc Med Bras (1992) ; 66(8): 1128-1133, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32935809

RESUMO

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.


Assuntos
Hemorroidas , Arginina/análogos & derivados , Humanos , Óxido Nítrico , Óxido Nítrico Sintase Tipo III
3.
Br Dent J ; 229(3): 147-148, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32811906
6.
Neurol Neurochir Pol ; 54(4): 323-328, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32510570

RESUMO

Atrial fibrillation (AF) and atherosclerotic disease are independent risk factors for acute ischaemic stroke (AIS). The optimal biological marker which could allow differentiation between AF and non-AF AIS patients is still not available. AIM OF THE STUDY: Aim of the present study was to investigate the role of pentosidine as a potential biological marker for AF in an AIS patient group. MATERIALS AND METHODS: Sixty-three acute ischaemic hemispheric stroke patients were recruited and divided into two groups according to the presumed underlying mechanism: with or without atrial rhythm disorders. Ten healthy volunteers were a reference group for serum level of pentosidine. Carotid artery ultrasound was performed, and common carotid artery stiffness and intima-media thickness were measured. Serum levels of pentosidine and selected routine biochemical risk factors for atherosclerosis (cholesterol and its lipoprotein fractions, homocysteine) were examined. RESULTS: A higher serum level of pentosidine was observed in patients without atrial fibrillation (1,509 ± 485.13pmol/ml); a statistically significant difference was observed compared to the reference group (1,041.52 ± 411.17pmol/ml; p = 0.01), but not the AF patients (1,438.19 ± 495.97pmol/ml; p = 0.59). No significant difference in the non-AF group compared to the AF group for carotid intima-media thickness (IMT)/stiffness and pentosidine serum level was recorded. CONCLUSIONS AND CLINICAL IMPLICATIONS: A higher serum level of pentosidine was observed in AIS patients without atrial fibrillation compared to the healthy volunteers. According to the results of the present study, no difference between these patients in the selected risk factors of atherosclerosis were observed. Further studies are needed to identify a reliable marker of AF that would bring added value to the standard diagnostic workup after acute ischaemic stroke.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , Acidente Vascular Cerebral , Arginina/análogos & derivados , Espessura Intima-Media Carotídea , Humanos , Lisina/análogos & derivados , Fatores de Risco
7.
Proc Natl Acad Sci U S A ; 117(27): 15862-15873, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32561647

RESUMO

Albuminuria is an independent risk factor for the progression to end-stage kidney failure, cardiovascular morbidity, and premature death. As such, discovering signaling pathways that modulate albuminuria is desirable. Here, we studied the transcriptomes of podocytes, key cells in the prevention of albuminuria, under diabetic conditions. We found that Neuropeptide Y (NPY) was significantly down-regulated in insulin-resistant vs. insulin-sensitive mouse podocytes and in human glomeruli of patients with early and late-stage diabetic nephropathy, as well as other nondiabetic glomerular diseases. This contrasts with the increased plasma and urinary levels of NPY that are observed in such conditions. Studying NPY-knockout mice, we found that NPY deficiency in vivo surprisingly reduced the level of albuminuria and podocyte injury in models of both diabetic and nondiabetic kidney disease. In vitro, podocyte NPY signaling occurred via the NPY2 receptor (NPY2R), stimulating PI3K, MAPK, and NFAT activation. Additional unbiased proteomic analysis revealed that glomerular NPY-NPY2R signaling predicted nephrotoxicity, modulated RNA processing, and inhibited cell migration. Furthermore, pharmacologically inhibiting the NPY2R in vivo significantly reduced albuminuria in adriamycin-treated glomerulosclerotic mice. Our findings suggest a pathogenic role of excessive NPY-NPY2R signaling in the glomerulus and that inhibiting NPY-NPY2R signaling in albuminuric kidney disease has therapeutic potential.


Assuntos
Albuminúria/metabolismo , Nefropatias/metabolismo , Neuropeptídeo Y/metabolismo , Receptores de Neuropeptídeo Y/metabolismo , Transdução de Sinais/fisiologia , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Benzazepinas/farmacologia , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas , Modelos Animais de Doenças , Regulação para Baixo , Doxorrubicina/farmacologia , Humanos , Insulina/metabolismo , Nefropatias/patologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Neuropeptídeo Y/farmacologia , Neuropeptídeo Y/urina , Podócitos/metabolismo , Proteômica , Receptores de Neuropeptídeo Y/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
8.
Eur J Protistol ; 74: 125705, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32464434

RESUMO

The ciliate Paramecium tetraurelia has four arginine kinase genes (AK1, AK2, AK3, and AK4). Of these genes, only AK3 has a signal sequence for farnesylation, a post-translational modification that enables anchoring of the modified enzyme to the ciliary membrane. To confirm this modification, AK3 was synthesized using a cell-free protein synthesis system and the peptide masses were analyzed using peptide mass fingerprinting (PMF). The PMF analysis indicated that the C-terminal peptide of AK3 is farnesylated. Thus, AK3 can be farnesylated under physiologically appropriate conditions. To determine the subcellular localization of P. tetraurelia AK3, Western blot analysis was performed using an AK3 polyclonal antibody for the proteins extracted from intact cells and ciliary fractions. When extraction was performed using Triton X-100, AK3 was detected the ciliary fraction. This result suggested that the ciliary fraction contains AK3. In addition, we investigated the role of P. tetraurelia AKs in ciliary movement using the feeding RNA interference method. The swimming velocity of AK1- and AK3-silenced cells was significantly reduced to half the value of that control cells. In summary, P. tetraurelia AK3 is likely to be located in the ciliary membrane and influences swimming velocity, presumably through the phosphoarginine shuttle system present in cilia.


Assuntos
Arginina Quinase/metabolismo , Arginina/análogos & derivados , Paramecium tetraurellia/enzimologia , Arginina/metabolismo , Cílios/enzimologia , Compostos Organofosforados/metabolismo
9.
Am J Physiol Renal Physiol ; 319(2): F215-F228, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32463727

RESUMO

Nitric oxide synthase inhibition by Nω-nitro-l-arginine methyl ester (l-NAME) plus a high-salt diet (HS) is a model of chronic kidney disease (CKD) characterized by marked hypertension and renal injury. With cessation of treatment, most of these changes subside, but progressive renal injury develops, associated with persistent low-grade renal inflammation. We investigated whether innate immunity, and in particular the NF-κB system, is involved in this process. Male Munich-Wistar rats received HS + l-NAME (32 mg·kg-1·day-1), whereas control rats received HS only. Treatment was ceased after week 4 when 30 rats were studied. Additional rats were studied at week 8 (n = 30) and week 28 (n = 30). As expected, HS + l-NAME promoted severe hypertension, albuminuria, and renal injury after 4 wk of treatment, whereas innate immunity activation was evident. After discontinuation of treatments, partial regression of renal injury and inflammation occurred, along with persistence of innate immunity activation at week 8. At week 28, glomerular injury worsened, while renal inflammation persisted and renal innate immunity remained activated. Temporary administration of the NF-κB inhibitor pyrrolidine dithiocarbamate, in concomitancy with the early 4-wk HS + l-NAME treatment, prevented the development of late renal injury and inflammation, an effect that lasted until the end of the study. Early activation of innate immunity may be crucial to the initiation of renal injury in the HS + l-NAME model and to the autonomous progression of chronic nephropathy even after cessation of the original insult. This behavior may be common to other conditions leading to CKD.


Assuntos
Arginina/análogos & derivados , Glomérulos Renais/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Insuficiência Renal Crônica/tratamento farmacológico , Animais , Arginina/metabolismo , Inibidores Enzimáticos/farmacologia , Rim/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Nefrite/fisiopatologia , Ratos Wistar , Insuficiência Renal Crônica/fisiopatologia , Cloreto de Sódio/farmacologia , Cloreto de Sódio na Dieta/farmacologia
10.
Food Chem ; 327: 127039, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32454273

RESUMO

In this study, we investigated the tailoring of food emulsions using interactions between rice bran cellulose nanocrystals (CNCs) and lauric arginate (LAE), which is food-grade cationic surfactant. Complexes of anionic CNCs and cationic LAE (CNCs/LAE) were formed through electrostatic attraction which were characterized using isothermal titration calorimetry (ITC), turbidity, and zeta-potential measurements. The saturation complexes could be formed at ratios of 1:2 (w/w) CNCs-to-LAE. Furthermore, the physical and oxidative stability of oil-in-water emulsions containing lipid droplets coated by CNCs/LAE complexes was determined. Electrostatic complexes formed from 0.02% CNCs and 0.1% LAE produced stable Pickering emulsions that were resistant to droplet coalescence. It was also exhibited that 0.02% CNCs and 0.1% LAE complexes stabilized-emulsions was able to extend the lag phase to 20 days for lipid hydroperoxide and to 14 days for hexanal production. This study shows that food-grade Pickering emulsions with good stability can be produced by CNCs with LAE complexes.


Assuntos
Arginina/análogos & derivados , Celulose/química , Alimentos , Nanopartículas/química , Óleos/química , Tensoativos/química , Água/química , Arginina/química , Emulsões , Eletricidade Estática
11.
J Laryngol Otol ; 134(4): 316-322, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32281535

RESUMO

BACKGROUND: Individuals on anticoagulation therapy are at increased risk of bleeding, including epistaxis. There is a lack of available reversal agents for novel oral anticoagulation therapy. OBJECTIVE: This paper reviews the current literature on epistaxis in the context of novel oral anticoagulation use, in order to recommend guidelines on management. METHOD: A comprehensive search of published literature was conducted to identify all relevant articles published up to April 2019. RESULTS: Patients on oral anticoagulation therapy are over-represented in individuals with epistaxis. Those on novel oral anticoagulation therapy were more likely to relapse compared to patients on classic oral anticoagulants or non-anticoagulated patients. Idarucizumab is an effective antidote for bleeding associated with dabigatran use. Recommendations for epistaxis management in patients on novel oral anticoagulation therapy are outlined. CONCLUSION: Clinicians need to be aware of the potential severity of epistaxis and the increased likelihood of recurrence. High-quality studies are required to determine the efficacy and safety of andexanet alfa and ciraparantag, as well as non-specific reversal agents.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antídotos/uso terapêutico , Epistaxe/tratamento farmacológico , Administração Oral , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Antídotos/administração & dosagem , Antitrombinas/efeitos adversos , Antitrombinas/uso terapêutico , Arginina/administração & dosagem , Arginina/análogos & derivados , Arginina/uso terapêutico , Conscientização , Dabigatrana/efeitos adversos , Dabigatrana/uso terapêutico , Epistaxe/induzido quimicamente , Epistaxe/epidemiologia , Fator Xa/administração & dosagem , Fator Xa/uso terapêutico , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/uso terapêutico , Primeiros Socorros/normas , Humanos , Masculino , Piperazinas/administração & dosagem , Piperazinas/uso terapêutico , Prevalência , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Rivaroxabana/efeitos adversos , Rivaroxabana/uso terapêutico , Índice de Gravidade de Doença
12.
Am J Vet Res ; 81(4): 375-380, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228261

RESUMO

OBJECTIVE: To establish a reference interval for glomerular filtration rate (GFR) determined by measuring serum clearance of a single IV dose of inulin in clinically normal cheetahs (Acinonyx jubatus) and compare serum symmetric dimethylarginine (SDMA) concentration in cheetahs with GFR. ANIMALS: 33 cheetahs housed at 3 institutions. PROCEDURES: A single bolus of inulin (3,000 mg/m2) was administered IV, and 5 serial blood samples were collected and analyzed for serum inulin concentration with the anthrone technique. The GFR was estimated with a modified slope-intercept method for the slow component of the serum concentration-versus-time curve. Blood urea nitrogen and serum creatinine concentrations were measured in samples obtained immediately prior to inulin administration, and serum SDMA concentration was measured in stored samples. RESULTS: Mean ± SD measured GFR was 1.58 ± 0.39 mL/min/kg, and the calculated reference interval was 0.84 to 2.37 mL/min/kg. There were significant negative correlations between GFR and serum creatinine concentration (r = -0.499), BUN concentration (r = -0.592), and age (r = -0.463). Serum SDMA concentration was not significantly correlated with GFR (r = 0.385), BUN concentration (r = -0.281), or serum creatinine concentration (r = 0.165). CONCLUSIONS AND CLINICAL RELEVANCE: A reference interval for GFR in clinically normal cheetahs was obtained. Further evaluation of animals with renal disease is needed to determine whether measuring serum clearance of a single IV dose of inulin is a reliable diagnostic test for early detection of renal disease in cheetahs.


Assuntos
Acinonyx , Animais , Arginina/análogos & derivados , Creatinina , Testes Diagnósticos de Rotina , Taxa de Filtração Glomerular , Inulina
13.
Environ Sci Pollut Res Int ; 27(14): 16246-16253, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32124290

RESUMO

Cadmium (Cd) is a naturally occurring toxic heavy metal with no known essential biological functions. Exposure to Cd increases the risk of cardiovascular disease by disrupting vascular homeostasis at the endothelium. The aim of the study was to evaluate the effect of chronic low-dose Cd on vascular structure and function. Fifty adult male Sprague Dawley rats were grouped and assigned to one of two treatments for 14 weeks. The control group received normal water for 14 weeks while the Cd-treated group received 15 mg Cd/kg B.W. as CdCl2 in water for 10 weeks. A subset of the Cd-treated group received 15 mg Cd/kg B.W. as CdCl2 in water for 10 weeks followed by 4 weeks of normal water. Results show an overall decline in vascular function and structure. Withdrawal of Cd treatment showed a considerable restoration of vascular structure and vasorelaxation function. Additionally, asymmetric dimethylarginine (ADMA) bioavailability was found to be lowered over time. Interestingly, the expression of eNOS in the Cd-treated group was found to be significantly elevated during the exposure by more than 3-fold in comparison with that in the control group. This protein expression was similar to the control group after the withdrawal of Cd treatment. Taken together, the results suggest that ADMA, an eNOS inhibitor, may play a role in altering endothelial function in the presence of cadmium. In conclusion, the findings indicate that even at low doses, Cd leads to endothelial dysfunction mediated by ADMA.


Assuntos
Cádmio , Endotélio Vascular , Animais , Arginina/análogos & derivados , Masculino , Óxido Nítrico , Ratos , Ratos Sprague-Dawley
14.
Aust Vet J ; 98(6): 247-249, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32189333

RESUMO

Oxalate nephrosis is a prevalent renal disease in koalas (Phascolarctos cinereus) of the Mount Lofty Ranges population in South Australia. The symmetric dimethylarginine (SDMA) assay is widely used in companion animals to diagnose renal disease, particularly in the early stages. This study aimed to determine: (1) reference intervals for SDMA in koalas and (2) SDMA values of koalas with oxalate nephrosis. Blood samples were collected from 41 Mount Lofty Ranges koalas euthanased on welfare grounds. Koalas were necropsied and, based on renal histopathology, were classified as unaffected (n = 22) or affected (n = 19) by oxalate nephrosis. Serum or plasma samples were analysed for creatinine, urea and SDMA and urine samples for urine specific gravity (USG). The reference interval for SDMA in unaffected koalas was 2.4-22.9 µg/dL. In koalas with oxalate nephrosis, SDMA was elevated in 74% of cases above the upper limit of the confidence interval. SDMA was elevated in three affected koalas with normal creatinine values. A positive correlation was found between SDMA and creatinine (R = 0.775, P < 0.001) and SDMA and urea (R = 0.580, P < 0.001) and a negative correlation between SDMA and USG (R = -0.495, P = 0.027). In conclusion, SDMA correlates well with other commonly used tests of renal function in koalas and should be included as part of the standard diagnostic process to increase the accuracy of oxalate nephrosis diagnosis in koalas.


Assuntos
Nefrose/veterinária , Phascolarctidae , Animais , Arginina/análogos & derivados , Oxalatos , Austrália do Sul
15.
Artigo em Inglês | MEDLINE | ID: mdl-32062367

RESUMO

Protein-arginine methyltransferases catalyze the methylation of the guanidine (NG) group of proteinic L-arginine (Arg) to produce monomethyl and dimethylarginine proteins. Their proteolysis releases the free amino acids monomethylarginine (MMA), symmetric dimethylarginine (SDMA) and asymmetric dimethylarginine (ADMA), respectively. MMA, SDMA and ADMA are inhibitors of the nitric oxide synthase (NOS) activity. High circulating and low urinary concentrations of ADMA and SDMA are considered risk factors in the cardiovascular and renal systems, mainly due to their inhibitory action on NOS activity. Identity, biological activity and concentration of NG-methylated proteins are largely unknown. The present study addressed these issues by using GC-MS and LC-MS/MS approaches. GC-MS was used to quantify free ADMA released by classical HCl-catalyzed hydrolysis of three synthetic Arg-vasopressin (V) peptides and of unknown endogenous NG-dimethylated proteins. The cyclic (c) disulfide forms of Arg-vasopressin analogs, i.e., Arg-vasopressin (cV-Arg-Gly-NH2), asymmetrically NG-dimethylated vasopressin (cV-ADMA-Gly-NH2) and symmetrically NG-dimethylated vasopressin (cV-SDMA-Gly-NH2) were used as model peptides in quantitative GC-MS analyses of ADMA, SDMA and other expected amino acids from the hydrolyzed Arg-vasopressin analogs. cV-ADMA-Gly-NH2 and cV-SDMA-Gly-NH2 were discriminated from cV-Arg-Gly-NH2 by LC-MS and LC-MS/MS, yet they were indistinguishable from each other. The same applies to the respective open (o) reduced and di-S-acetamide forms of oV-ADMA-Gly-NH2, oV-SDMA-Gly-NH2 and oV-Arg-Gly-NH2. Our LC-MS and LC-MS/MS studies suggest that the Arg-vasopressin analogs form [(M-H)]+ and [(M-H)+H]+ in the positive ESI mode and undergo in part conversion of their terminal Gly-NH2 (NH2, 16 Da) group to Gly-OH (OH, 17 Da). The product ion mass spectra of the di-S-acetamide forms are complex and contain several intense mass fragments differing by 1 Da. cV-ADMA-Gly-NH2 and cV-SDMA-Gly-NH2 induced platelet aggregation in platelet-rich human plasma with moderately different initial velocity and maximal aggregation rates compared to cV-Arg-Gly-NH2. Previous studies showed that human red blood cells are rich in large (>50 kDa) ADMA-containing proteins of unknown identity. Our LC-MS/MS proteomic study identified several membrane and cytosolic erythrocytic NG-dimethylated proteins, including spectrin-α (280 kDa), spectrin-ß (247 kDa) and protein 4.1 (80 kDa). Being responsible for the stability of the erythrocyte membrane, the newly identified main targets for NG-dimethylation in human erythrocytes should be given a closer look in erythrocytic diseases like hereditary spherocytosis.


Assuntos
Arginina Vasopressina , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Guanidina/química , Espectrometria de Massas em Tandem/métodos , Arginina/análogos & derivados , Arginina/análise , Arginina/sangue , Arginina/química , Arginina Vasopressina/análise , Arginina Vasopressina/sangue , Arginina Vasopressina/química , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/química , Humanos , Modelos Lineares , Masculino , Peptídeos/análise , Peptídeos/sangue , Peptídeos/química , Projetos Piloto , Processamento de Proteína Pós-Traducional
16.
Adv Exp Med Biol ; 1202: 243-258, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32034717

RESUMO

The observations that numerous cancers are characterized by impairment in arginine synthesis and that deficit of exogenous arginine specifically affects their growth and viability are the ground for arginine deprivation-based anticancer treatment strategy. This review addresses molecular mechanisms of the human glioblastoma cell response to arginine deprivation. Our earlier studies have shown that arginine deprivation specifically impairs glioblastoma cell motility, adhesion and invasiveness. These changes were evoked by alterations in the actin cytoskeleton organization resulting from a decreased arginylation of ß-actin isoform. Moreover, deficit of arginine induces prolonged endoplasmic reticulum (ER) stress and activation of the unfolded protein response, not leading, however, to a massive apoptosis in glioblastoma cells. Our current research indicates that cell death could be augmented by other compounds such as modulators of ER stress, for example arginine analogue of plant origin, canavanine. Implication of these studies on the development of new anti-glioma metabolic therapeutic modalities are discussed.


Assuntos
Arginina/deficiência , Arginina/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Transdução de Sinais , Animais , Arginina/análogos & derivados , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Humanos , Transdução de Sinais/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos dos fármacos
17.
Kidney Int ; 97(3): 450-452, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32087885

RESUMO

Patients with end-stage renal disease have a high risk of dying from cardiovascular disease that cannot be explained solely by traditional cardiovascular disease risk factors. Hesse et al. suggest that dysfunctional high-density lipoprotein cholesterol generated in patients with end-stage renal disease causes endothelial glycocalyx degradation. Glycocalyx degradation may represent one of the earliest insults leading to atheroma formation, and so this work suggests a novel link between renal failure and cardiovascular disease.


Assuntos
Glicocálix , Insuficiência Renal Crônica , Arginina/análogos & derivados , Humanos , Lipoproteínas HDL
18.
Adv Clin Exp Med ; 29(1): 63-70, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31967743

RESUMO

BACKGROUND: The most commonly recognized cardiovascular risk factors (CVRF) include smoking cigarettes, manifestation of arterial hypertension (AH), hypercholesterolemia, hypertriglyceridemia, manifestation of type 2 diabetes mellitus (DM), and the presence of overweight or obesity. In recent years, investigations have documented the significance of asymmetric dimethylarginine concentration (ADMA) in the pathogenesis of diseases affecting the cardiovascular system. OBJECTIVES: To evaluate the relationship between the number of CVRF and blood ADMA concentration. MATERIAL AND METHODS: The study was conducted on a sample of 138 individuals (mean age 54.90 ±10.38 years). Among the participants, we distniguished subgroups with no CVRF (group A, n = 21), with 1-2 CVRF (group B, n = 53), with 3-4 CVRF (group C, n = 55), and with 5-6 CVRF (group D, n = 9). Plasma concentrations of arginine and of endogenous methylarginines were estimated. RESULTS: Plasma ADMA concentrations proved to be significantly higher in groups B, C and D than those in group A. Regression analysis allowed us to demonstrate that in the studied population of patients, manifestation of type 2 DM, followed by AH and hypercholesterolemia, were linked to the highest probability of elevated plasma ADMA concentration. CONCLUSIONS: Higher concentration of ADMA in the blood may be a marker for higher cardiovascular risk, especially associated with hypertension, type 2 DM and hypercholesterolemia.


Assuntos
Arginina/análogos & derivados , Biomarcadores , Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Adulto , Idoso , Arginina/sangue , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Diabetes Mellitus Tipo 2/sangue , Humanos , Pessoa de Meia-Idade , Fatores de Risco
19.
PLoS One ; 15(1): e0227964, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31990929

RESUMO

Hyperthyroidism in cats can mask changes in renal function, including chronic kidney disease (CKD), because of hyperfiltration and muscle loss. Symmetric dimethylarginine (SDMA) has been shown to increase earlier than creatinine in cats with renal dysfunction, and, unlike creatinine, SDMA is not impacted by lean muscle mass. The aim of this study was to describe the relationship between SDMA, creatinine, body weight and TT4 over time during treatment of hyperthyroidism. Cats were retrospectively identified from the US IDEXX Reference Laboratories database where TT4, SDMA and creatinine were measured on the same cat at multiple time points. A hyperthyroid treated group was identified (TT4 ≤ 4.7 µg/dL and decreased by a minimum of 2.5 µg/dL) that had body weight and laboratory results available from more than one visit, and was used to evaluate body weight, creatinine, SDMA and TT4 pre-treatment and at 1-30, 31-60, 61-90, 91-120 days post-treatment. Creatinine significantly decreased with increasing concentrations of TT4 (Spearman's ρ = -0.37, P < 0.001), whereas SDMA did not. Body weight, SDMA and creatinine concentrations significantly increased during the immediate 1-30 day post-treatment period (P < 0.012, P < 0.001, P < 0.001, respectively). During treatment creatinine continued to increase as cats gained weight. In contrast, SDMA remained stable during treatment and was comparable to age-matched control cats. Therefore, SDMA may be a more reliable biomarker of renal function than creatinine in hyperthyroid cats before and during treatment.


Assuntos
Arginina/análogos & derivados , Creatinina/sangue , Hipertireoidismo/sangue , Insuficiência Renal Crônica/sangue , Animais , Arginina/sangue , Biomarcadores/sangue , Peso Corporal/fisiologia , Gatos , Testes Diagnósticos de Rotina , Feminino , Taxa de Filtração Glomerular/fisiologia , Hipertireoidismo/patologia , Hipertireoidismo/veterinária , Rim/metabolismo , Rim/patologia , Masculino , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/veterinária , Estudos Retrospectivos
20.
Am J Physiol Renal Physiol ; 318(2): F509-F517, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31904280

RESUMO

Endothelial dysfunction, characterized by reduced bioavailability of nitric oxide and increased oxidative stress, is a hallmark characteristic in diabetes and diabetic nephropathy (DN). High levels of asymmetric dimethylarginine (ADMA) are observed in several diseases including DN and are a strong prognostic marker for cardiovascular events in patients with diabetes and end-stage renal disease. ADMA, an endogenous endothelial nitric oxide synthase (NOS3) inhibitor, is selectively metabolized by dimethylarginine dimethylaminohydrolase (DDAH). Low DDAH levels have been associated with cardiac and renal dysfunction, but its effects on DN are unknown. We hypothesized that enhanced renal DDAH-1 expression would improve DN by reducing ADMA and restoring NOS3 levels. DBA/2J mice injected with multiple low doses of vehicle or streptozotocin were subsequently injected intrarenally with adenovirus expressing DDAH-1 (Ad-h-DDAH-1) or vector control [Ad-green fluorescent protein (GFP)], and mice were followed for 6 wk. Diabetes was associated with increased kidney ADMA and reduced kidney DDAH activity and DDAH-1 expression but had no effect on kidney DDAH-2 expression. Ad-GFP-treated diabetic mice showed significant increases in albuminuria, histological changes, glomerular macrophage recruitment, inflammatory cytokine and fibrotic markers, kidney ADMA levels, and urinary thiobarbituric acid reactive substances excretion as an indicator of oxidative stress, along with a significant reduction in kidney DDAH activity and kidney NOS3 mRNA compared with normal mice. In contrast, Ad-h-DDAH-1 treatment of diabetic mice reversed these effects. These data indicate, for the first time, that DDAH-1 mediates renal tissue protection in DN via the ADMA-NOS3-interaction. Enhanced renal DDAH-1 activity could be a novel therapeutic tool for treating patients with diabetes.


Assuntos
Adenoviridae/genética , Amidoidrolases/biossíntese , Arginina/análogos & derivados , Diabetes Mellitus Experimental/terapia , Nefropatias Diabéticas/prevenção & controle , Terapia Genética , Vetores Genéticos , Rim/enzimologia , Albuminúria/enzimologia , Albuminúria/genética , Albuminúria/prevenção & controle , Amidoidrolases/genética , Animais , Arginina/metabolismo , Citocinas/genética , Citocinas/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/genética , Nefropatias Diabéticas/enzimologia , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/genética , Fibrose , Mediadores da Inflamação/metabolismo , Rim/patologia , Masculino , Camundongos Endogâmicos DBA , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo , Transdução de Sinais , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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