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1.
Bol. latinoam. Caribe plantas med. aromát ; 20(3): 303-314, may. 2021. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1343478

RESUMO

In this study, against streptozotocin (STZ) induced diapetic nephropathy (DN); it is aimed to investigate the use of thymoquinone (TQ) and ß-aminoisobutyric acid (BAIBA) and to compare the effects of these agents. With random selection of 35 male rats, five groups (seven rats in each group) were constituted as follows: Control, STZ, STZ + TQ, STZ + BAIBA, STZ + TQ + BAIBA. In the STZ group; body weight, glutathione (GSH) and insulin levels decreased, relative kidney weight, malondialdehyde (MDA), glucose, blood urea nitrogen (BUN) and creatinine (Cr) levels were increased. Also, in kidney tissue; histopathological changes (such as thickening of the capsular, glomerular and tubular basement membranes, increased mesangial matrix amount, increased cytoplasmic vacuolization in some of the tubular epithelial cells, increased tumor necrosis factor-alpha (TNF-α) expression, and inflammatory cell infiltrations in interstitial tissue) were detected. It was observed that these changes occurring after diabetes mellitus (DM) reversed significantly in TQ, BAIBA and TQ + BAIBA groups.


En este estudio, contra la nefropatía diapética (ND) inducida por estreptozotocina (STZ); tiene como objetivo investigar el uso de timoquinona (TQ) y ácido ß-aminoisobutírico (BAIBA) y comparar los efectos de estos agentes. Con la selección aleatoria de 35 ratas macho, se constituyeron cinco grupos (siete ratas en cada grupo) como sigue: Control, STZ, STZ + TQ, STZ + BAIBA, STZ + TQ + BAIBA. En el grupo STZ; el peso corporal, los niveles de glutatión (GSH) y de insulina disminuyeron, el peso relativo de los riñones, el malondialdehído (MDA), la glucosa, el nitrógeno ureico en sangre (BUN) y los niveles de creatinina (Cr) aumentaron. Además, en tejido renal; se detectaron cambios histopatológicos (como engrosamiento de las membranas basales capsular, glomerular y tubular, aumento de la cantidad de matriz mesangial, aumento de la vacuolización citoplasmática en algunas de las células epiteliales tubulares, aumento de la expresión del factor de necrosis tumoral alfa (TNF-α) e infiltraciones de células inflamatorias en tejido intersticial). Se observó que estos cambios que ocurren después de la diabetes mellitus (DM) se revirtieron significativamente en los grupos TQ, BAIBA y TQ + BAIBA.


Assuntos
Animais , Masculino , Ratos , Benzoquinonas/administração & dosagem , Nefropatias Diabéticas/tratamento farmacológico , Ácidos Aminoisobutíricos/administração & dosagem , Nitrogênio da Ureia Sanguínea , Peso Corporal , Imuno-Histoquímica , Ratos Sprague-Dawley , Estreptozocina , Estresse Oxidativo , Creatinina/análise , Modelos Animais de Doenças , Glucose/análise , Glutationa/análise , Rim/efeitos dos fármacos
2.
BMC Infect Dis ; 21(1): 389, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33906643

RESUMO

BACKGROUND: In patients with hepatitis C virus (HCV) and malignant lymphoma, hepatitis C flare during R-CHOP can result in discontinuation of treatment. However, appropriate therapeutic strategies for managing hepatitis C flare during R-CHOP have not been established, and this issue is complicated by conflicting results regarding the use of direct-acting antivirals in patients with uncontrolled malignancies. CASE PRESENTATION: We report the first case of effective and safe treatment with on-demand 8-week glecaprevir and pibrentasvir for hepatitis C flare during R-CHOP in a patient with diffuse large B-cell lymphoma (DLBCL). The patient completed five additional courses of R-CHOP without hepatic toxicity. A complete response of DLBCL and a sustained virological response were observed at 24 weeks after glecaprevir and pibrentasvir completion. CONCLUSION: On-demand, direct-acting antivirals could be a novel strategy for managing hepatitis C flare during R-CHOP.


Assuntos
Ácidos Aminoisobutíricos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antivirais/administração & dosagem , Benzimidazóis/administração & dosagem , Ciclopropanos/administração & dosagem , Hepacivirus/genética , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Lactamas Macrocíclicas/administração & dosagem , Leucina/análogos & derivados , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Prolina/análogos & derivados , Quinoxalinas/administração & dosagem , Sulfonamidas/administração & dosagem , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Genótipo , Humanos , Leucina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Prolina/administração & dosagem , Pirrolidinas , RNA Viral/sangue , RNA Viral/genética , Rituximab/uso terapêutico , Resposta Viral Sustentada , Vincristina/uso terapêutico , Carga Viral/efeitos dos fármacos
3.
Int J Oncol ; 53(6): 2737-2744, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30334568

RESUMO

The non­natural amino acid positron emission tomography tracers, 2­amino[3­11C]isobutyric acid ([3­11C]AIB) and 2­amino[11C]methyl­isobutyric acid ([11C]MeAIB), are metabolically stable in vivo and accumulate in tumors. [3­11C]AIB is transported into cells mainly via the amino acid transport system A and partially via systems L and ASC, whereas [11C]MeAIB is transported into cells specifically via system A. How transport via the different systems affects the tumor uptake of these tracers, however, is unclear. In the present study, the tumor uptake of the two tracers was directly compared in eight lung cancer models (A549, H82, H441, H460, H1299, H1650, PC14, and SY), and the correlation of tumor uptake with several factors (amino acid transporter expression, contribution of amino acid transport systems to AIB uptake and tumor proliferation indices) was analyzed. Biodistribution analyses revealed that the tumor uptake of [3­11C]AIB (4.9 to 19.2% injected dose per gram [ID/g]) was higher than that of [11C]MeAIB (3.1 to 15.9% ID/g) in all eight tumors, with a statistically significant difference in three tumors (P<0.01 in H441 and H460 tumors, P<0.05 in H82 tumors). A significant correlation was observed between the tumor uptake of the two tracers (r=0.95, P<0.01). The mRNA expression levels of the amino acid transporters of system A (SLC38A1 and SLC38A2), system L (SLC7A5) and system ASC (SLC1A5) were higher in all eight tumors than in the normal lung, with widely varying expression patterns. Although the contributions of the amino acid transport systems, Ki­67 indices and tumor doubling times greatly differed among the eight models, these factors did not correlate with the tumor uptake of either tracer. The higher tumor uptake of [3­11C]AIB and the correlation of tumor uptake between [3­11C]AIB and [11C]MeAIB warrant further investigation in clinical studies in order to clarify the role of [3­11C]AIB PET in oncology imaging.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros/genética , Ácidos Aminoisobutíricos/farmacocinética , Neoplasias Pulmonares/diagnóstico por imagem , beta-Alanina/análogos & derivados , Células A549 , Ácidos Aminoisobutíricos/administração & dosagem , Animais , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Tomografia por Emissão de Pósitrons , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto , beta-Alanina/administração & dosagem , beta-Alanina/farmacologia
4.
Mol Genet Metab ; 110 Suppl: S71-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23999161

RESUMO

BACKGROUND: Our laboratory seeks a pharmacotherapeutic intervention for PKU that utilizes non-physiological amino acids (NPAAs) to block the accumulation of phenylalanine (Phe) in the brain. In previous studies (Vogel et al. 2013), methylation of the amino group of 2-aminoisobutyrate (AIB) provided an enhanced degree of selectivity for Phe restriction into the brain of Pah(enu2) mice in comparison to unmethylated AIB, leading to the hypothesis that 2-(methylamino)alkanoic acid analogs of AIB might represent targeted inhibitors of Phe accretion into the brain. METHODS: Pah(enu2) and control mice were intraperitoneally administered (500-750 mg/kg body weight, once daily; standard 19% protein diet) AIB, methyl AIB (MAIB), isovaline, and two MAIB analogs, 2-methyl-2-(methylamino)butanoic (MeVal) and 3-methyl-2-(methylamino)pentanoic (MePent) acids for one week, followed by brain and blood isolation for amino acid analyses using UPLC. RESULTS: In the brain, AIB significantly reduced Phe accretion in Pah(enu2) mice, while MeVal significantly improved glutamine and aspartic acids. Four of five test compounds improved brain threonine and arginine levels. AIB, MAIB and IsoVal significantly reduced blood Phe, with no effect of any drug intervention on other sera amino acids. CONCLUSIONS: Further evaluation of AIB and the 2-(methylamino)alkanoic acids as inhibitors of brain Phe accumulation in Pah(enu2) mice is warranted, with more detailed evaluations of route of administration, combinatorial intervention, and detailed toxicity studies.


Assuntos
Ácidos Acíclicos/farmacologia , Ácidos Aminoisobutíricos/farmacologia , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Isoleucina/análogos & derivados , Fenilalanina/metabolismo , Fenilcetonúrias/tratamento farmacológico , Valina/análogos & derivados , Ácidos Acíclicos/administração & dosagem , Ácidos Aminoisobutíricos/administração & dosagem , Animais , Modelos Animais de Doenças , Humanos , Isoleucina/administração & dosagem , Isoleucina/farmacologia , Transportador 1 de Aminoácidos Neutros Grandes/química , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Metilação , Camundongos , Camundongos Transgênicos , Terapia de Alvo Molecular , Especificidade de Órgãos , Fenilalanina/sangue , Conformação Proteica , Dobramento de Proteína , Valina/administração & dosagem , Valina/farmacologia
5.
Clin Cancer Res ; 4(6): 1549-55, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9626476

RESUMO

To assess how to maximize drug delivery to intracerebral tumors and surrounding brain, this study examined the effects of route and method of administration and tumor size on the distribution of three agents in a nude rat intracerebral tumor xenograft model. Aminoisobutyric acid (M(r) 103), methotrexate (M(r) 454), and dextran 70 (M(r) 70,000) were administered i.v. or intra-arterially (i.a.) with or without osmotic blood-brain barrier disruption (BBBD) at 8, 12, or 16 days after tumor cell inoculation (n = 72). A 2.2- to 2.5-fold increase in delivery to tumor and surrounding brain was observed when i.a. was compared with i.v., and a 2.5- to 7.6-fold increase was observed when BBBD was compared with the saline control. The combined effect of i.a. administration and BBBD was to increase delivery 6.3-16.7-fold. The greatest benefit of BBBD was seen in animals with 8-day tumors, whereas BBBD had less benefit in improving delivery to intracerebral tumor and brain around tumor as the tumors grew larger. Regional delivery decreased as the molecular weight of the agent increased. Based on these results, we suggest that i.a. administration of antitumor agents may be adequate to obtain initial responses in large, very permeable, intracerebral tumors. However, in smaller, less permeable tumors or after an initial response to treatment, there may be a significant therapeutic advantage to i.a. agent administration and BBBD.


Assuntos
Ácidos Aminoisobutíricos/farmacocinética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Carcinoma de Células Pequenas/patologia , Neoplasias Pulmonares/patologia , Metotrexato/farmacocinética , Ácidos Aminoisobutíricos/administração & dosagem , Ácidos Aminoisobutíricos/sangue , Animais , Barreira Hematoencefálica , Neoplasias Encefálicas/secundário , Carcinoma de Células Pequenas/metabolismo , Dextranos/administração & dosagem , Dextranos/sangue , Dextranos/farmacocinética , Feminino , Humanos , Injeções Intra-Arteriais , Injeções Intravenosas , Neoplasias Pulmonares/metabolismo , Metotrexato/administração & dosagem , Metotrexato/sangue , Permeabilidade , Ratos , Ratos Nus , Análise de Regressão , Transplante Heterólogo , Trítio , Células Tumorais Cultivadas
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