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1.
Food Chem ; 404(Pt A): 134528, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36444010

RESUMO

To address consumer-level food waste, and pollution from commercial plastics, we developed intelligent films using sodium alginate (SA), pectin (PC), cellulose nanocrystals (CNCs), and anthocyanins extracted from red cabbage (RCA). We also investigated two methods of reinforcing these films - cross-linking (CL), and the addition of CNCs. Both together and separately, these methods improved SA/PC films' mechanical properties and thermal stability. The optimal SA/PC/CNCs/RCA/CL films exhibited pH-dependent color-response properties and high water resistance. These were then tested as colorimetric freshness indicators for shrimp samples, both through seepage and the monitoring of volatile compounds. The colors of the indicators changed from lilac to dark green to greenish-yellow after storage at 25 °C for 72 h, whereas at 4 °C, they changed much more slowly over the same time period. This demonstrated the excellent potential of such films to reduce food waste by providing real-time warnings of pH variation resulting from spoilage.


Assuntos
Nanopartículas , Eliminação de Resíduos , Pectinas , Celulose , Alginatos , Antocianinas , Alimentos Marinhos
2.
Cell Death Dis ; 12(4): 362, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824276

RESUMO

Adhesion G protein-coupled receptor A1 (ADGRA1, also known as GPR123) belongs to the G protein-coupled receptors (GPCRs) family and is well conserved in the vertebrate lineage. However, the structure of ADGRA1 is unique and its physiological function remains unknown. Previous studies have shown that Adgra1 is predominantly expressed in the central nervous system (CNS), indicating its important role in the transduction of neural signals. The aim of this study is to investigate the central function of Adgra1 in vivo and clarify its physiological significance by establishing an Adgra1-deficient mouse (Adgra1-/-) model. The results show that Adgra1-/- male mice exhibit decreased body weight with normal food intake and locomotion, shrinkage of body mass, increased lipolysis, and hypermetabolic activity. Meanwhile, mutant male mice present elevated core temperature coupled with resistance to hypothermia upon cold stimulus. Further studies show that tyrosine hydroxylase (TH) and ß3-adrenergic receptor (ß3-AR), indicators of sympathetic nerve excitability, are activated as well as their downstream molecules including uncoupling protein 1 (UCP1), coactivator 1 alpha (PGC1-α) in brown adipose tissue (BAT), and hormone-sensitive lipase (HSL) in white adipose tissue (WAT). In addition, mutant male mice have higher levels of serum T3, T4, accompanied by increased mRNAs of hypothalamus-pituitary-thyroid axis. Finally, Adgra1-/- male mice present abnormal activation of PI3K/AKT/GSK3ß and MEK/ERK pathways in hypothalamus. Overexpression of ADGRA1 in Neuro2A cell line appears to suppress these two signaling pathways. In contrast, Adgra1-/- female mice show comparable body weight along with normal metabolic process to their sex-matched controls. Collectively, ADGRA1 is a negative regulator of sympathetic nervous system (SNS) and hypothalamus-pituitary-thyroid axis by regulating PI3K/AKT/GSK3ß and MEK/ERK pathways in hypothalamus of male mice, suggesting an important role of ADGRA1 in maintaining metabolic homeostasis including energy expenditure and thermogenic balance.


Assuntos
Tecido Adiposo Branco/metabolismo , Hipotálamo/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Termogênese/fisiologia , Tecido Adiposo Marrom/metabolismo , Animais , Metabolismo Energético/fisiologia , Masculino , Camundongos , Obesidade/metabolismo , Transdução de Sinais/fisiologia , Sistema Nervoso Simpático/metabolismo , Glândula Tireoide/metabolismo
3.
Zhongguo Zhong Yao Za Zhi ; 46(3): 678-684, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33645035

RESUMO

The purpose of this study was to understand the pharmacodynamic effect of Valeriana jatamansi extract in diarrhea predominant irritable bowel syndrome(IBS-D) rat model induced by maternal separation combined with three kinds of stress, and observe the changes of endogenous metabolites in feces after intervention to find potential biomarkers and related metabolic pathways. The animal model of IBS-D was established by maternal separation combined with restraint, ice swimming and tail clamping. The therapeutic effect of each dose group of V. jatamansi extract was evaluated in terms of abdominal withdrawal reflex pressure threshold, fecal water content and immobility time of forced swimming test. In addition, rat feces were collected for detection of metabolic profiles of small molecular metabolites with UPLC-LTQ-Orbitrap MS platform, so as to find the biomarkers of differential metabolism with multivariate statistical analysis methods such as principal component analysis(PCA) and orthogon partial least squares discrimination analysis(OPLS-DA). The results showed that as compared with the normal group, the threshold of abdominal withdrawal reflex pressure was decreased, the fecal water content was increased, and the immobility time of forced swimming test was prolonged in the model group. The results of fecal metabonomics showed that the levels of 39 metabolites were down-regulated and those of 37 metabolites were up-re-gulated. Further analysis showed that these metabolites were related to bile acid metabolism, unsaturated fatty acid metabolism, amino acid metabolism, ceramide metabolism and other metabolic pathways. This study proved that the extract of V. jatamansi had definite pharmacodynamic effect on IBS-D model rats, and the mechanism was discussed from the perspective of fecal metabonomics.


Assuntos
Síndrome do Intestino Irritável , Valeriana , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Diarreia , Fezes , Síndrome do Intestino Irritável/tratamento farmacológico , Privação Materna , Metabolômica , Ratos , Espectrometria de Massas em Tandem
4.
Int J Mol Sci ; 22(3)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572934

RESUMO

(1) Background: Antifolate methotrexate (MTX) is the most common disease-modifying antirheumatic drug (DMARD) for treating human rheumatoid arthritis (RA). The mitochondrial-produced formate is essential for folate-mediated one carbon (1C) metabolism. The impacts of MTX on formate homeostasis in unknown, and rigorously controlled kinetic studies can greatly help in this regard. (2) Methods: Combining animal model (8-week old female C57BL/6JNarl mice, n = 18), cell models, stable isotopic tracer studies with gas chromatography/mass spectrometry (GC/MS) platforms, we systematically investigated how MTX interferes with the partitioning of mitochondrial and cytosolic formate metabolism. (3) Results: MTX significantly reduced de novo deoxythymidylate (dTMP) and methionine biosyntheses from mitochondrial-derived formate in cells, mouse liver, and bone marrow, supporting our postulation that MTX depletes mitochondrial 1C supply. Furthermore, MTX inhibited formate generation from mitochondria glycine cleavage system (GCS) both in vitro and in vivo. Folinate selectively rescued 1C metabolic pathways in a tissue-, cellular compartment-, and pathway-specific manner: folinate effectively reversed the inhibition of mitochondrial formate-dependent 1C metabolism in mouse bone marrow (dTMP, methionine, and GCS) and cells (dTMP and GCS) but not methionine synthesis in liver/liver-derived cells. Folinate failed to fully recover hepatic mitochondrial-formate utilization for methionine synthesis, suggesting that the efficacy of clinical folinate rescue in MTX therapy on hepatic methionine metabolism is poor. (4) Conclusion: Conducting studies in mouse and cell models, we demonstrate novel findings that MTX specifically depletes mitochondrial 1C supply that can be ameliorated by folinate supplementation except for hepatic transmethylation. These results imply that clinical use of low-dose MTX may particularly impede 1C metabolism via depletion of mitochondrial formate. The MTX induced systematic and tissue-specific formate depletion needs to be addressed more carefully, and the efficacy of folinate with respect to protecting against such depletion deserves to be evaluated in medical practice.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Formiatos/metabolismo , Leucovorina/uso terapêutico , Metotrexato/uso terapêutico , Complexo Vitamínico B/uso terapêutico , Animais , Antirreumáticos/farmacologia , Artrite Reumatoide/metabolismo , Suplementos Nutricionais , Feminino , Humanos , Leucovorina/farmacologia , Redes e Vias Metabólicas/efeitos dos fármacos , Metotrexato/farmacologia , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Complexo Vitamínico B/farmacologia
5.
Biomed Chromatogr ; 33(9): e4563, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31025385

RESUMO

Astragali Radix (AR) is a widely used traditional Chinese medicine for healing the cardiovascular, liver and immune systems. Recently, superfine pulverizing technology has been applied to developing novel formulations to improve bioavailability of the active constituents in herbs, such as ultrafine granular powder of AR. In this study, a universal and sensitive quantitative method based on LC-MS/MS was employed for determining formononetin, the main flavonoid in AR, in human plasma for comparative pharmacokinetics of three oral formulations of AR. Formononetin and IS (quercetin) were extracted by ethyl acetate from human plasma and were separated on a C18 column with a mobile phase consisting of acetonitrile and 0.1% formic acid. Positive-ion electrospray-ionization mode was applied in mass spectrometric detection. The quantitative method was validated with regards to selectivity, linearity, accuracy and precision, matrix effect, extraction recovery and stability, and was applied to comparing the pharmacokinetics of ultrafine granular powder (UGP), ultrafine powder (UP) and traditional decoction pieces (TDP) of AR after oral administration. The peak concentration and areas under the concentration-time curve of formononetin in UGP and UP were significantly higher than those of TDP. UGP and UP could significantly improve the bioavailability of AR in human compared with TDP after oral administration.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Isoflavonas/sangue , Isoflavonas/farmacocinética , Espectrometria de Massas em Tandem/métodos , Adolescente , Adulto , Astragalus propinquus , Estabilidade de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Humanos , Isoflavonas/química , Limite de Detecção , Modelos Lineares , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
6.
Bioanalysis ; 11(5): 365-380, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30873858

RESUMO

AIM: Ginsenoside compound K (CK) is considered to be a potential therapeutic drug for rheumatoid arthritis because of its good anti-inflammatory activity. The purpose of this work was to establish a rapid, sensitive and specific method for determination of CK and its active metabolite 20(S)-protopanaxadiol (20(S)-PPD). Materials & methods: The analytes and internal standards were extracted by liquid-liquid extraction. Then, were separated by high performance liquid phase and determined by triple quadrupole mass spectrometry. RESULTS: A LC-MS/MS using liquid-liquid extraction was developed for determining CK over the concentration range 1.00-1002.00 ng/ml and 0.15-54.30 ng/ml for 20(S)-PPD. The lower limits of quantification for CK and 20(S)-PPD were 1.00 and 0.15 ng/ml, respectively. CONCLUSION: This method was successfully validated for detecting both CK and 20(S)-PPD in the human plasma and urine, and was proved to be suitable for the pharmacokinetic study of CK in healthy Chinese volunteers. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR-TRC-14004824.


Assuntos
Cromatografia Líquida/métodos , Ginsenosídeos/uso terapêutico , Panax/química , Sapogeninas/uso terapêutico , Espectrometria de Massas em Tandem/métodos , Artrite Reumatoide , Feminino , Ginsenosídeos/farmacologia , Humanos , Masculino , Sapogeninas/farmacologia
7.
ACS Nano ; 13(2): 2349-2356, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30681827

RESUMO

Blue energy harvested from ocean waves is an important and promising renewable energy source for sustainable development of our society. Triboelectric nanogenerators (TENGs) and electromagnetic energy harvesters (EMGs) both are considered promising approaches for harvesting blue energy. In this work, a hybridized triboelectric-electromagnetic water wave energy harvester (WWEH) based on a magnetic sphere is presented. A freely rolling magnetic sphere senses the water motion to drive the friction object sliding on a solid surface for TENG back and forth. At the same time, two coils transform the motion of the magnetic sphere into electricity according to the electromagnetic induction effect. For harvesting the blue energy from any direction, the electrodes of the TENG are specified as the Tai Chi shape, the effective of which is analyzed and demonstrated. Based on a series of experimental comparisons, the two friction layers and the two coils are specified to be connected in parallel and in series, respectively. A paper-based supercapacitor of ∼1 mF is fabricated to store the generated energy. The WWEH is placed on a buoy to test in Lake Lanier. During 162 s, the supercapacitor can be charged to 1.84 V, the electric energy storage in it is about 1.64 mJ. This work demonstrates that the WWEH can be successfully used for driving distributed, self-powered sensors for environmental monitoring.

8.
Zhongguo Zhong Yao Za Zhi ; 42(2): 347-351, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-28948742

RESUMO

This study aimed to investigate the effects of baldrinal of Valeriana jatamansi on the expression of corticotropin releasing factor (CRF) and tryptophan hydroxylase 1 (TPH1) mRNA and levels of 5-hydroxytryptamine (5-HT) in colon of rats with irritable bowel syndrome (IBS), and to explain its therapeutic mechanism on IBS through 5-HT pathway. Fifty-four male SD rats were randomly divided into 6 groups: blank group, model group, baldrinal high, medium and low dose groups, and pinaverium bromide group, n=9 in each group. The IBS rat models were established by using unpredictable chronic stress for 3 weeks followed by 1-hour acute restraint stress (CAS) after 7 days of rest and independent feeding. CRF expression was detected by IHC-P; TPH1 mRNA expression was detected by using RT-PCR and the 5-HT level was measured by high performance liquid chromatography(HPLC). The results indicated that the method of chronic stress with acute restrain stress method and independent feeding could lead to the increase in expressions of CRF and TPH1 mRNA and levels of 5-HT in IBS rats(P<0.05). The expressions of CRF, TPH1 mRNA and 5-HT in baldrinal groups were significantly lower than those in model group(P<0.05). The experimental results showed that IBS could result in increase in the expressions of CRF, TPH1 mRNA and levels of 5-HT, and the baldrinal of V. jatamansi could improve the symptoms of IBS by reducing the expressions of CRF, TPH1 mRNA and levels of 5-HT in colon of rats.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Iridoides/farmacologia , Síndrome do Intestino Irritável/tratamento farmacológico , Serotonina/metabolismo , Triptofano Hidroxilase/metabolismo , Valeriana/química , Animais , Colo/efeitos dos fármacos , Colo/metabolismo , Síndrome do Intestino Irritável/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
9.
J Clin Oncol ; 35(26): 3021-3029, 2017 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-28767288

RESUMO

Purpose The Children's Oncology Group AAML0631 trial for newly diagnosed pediatric acute promyelocytic leukemia (APL) was a phase III historically controlled trial to determine the survival of patients receiving arsenic trioxide (ATO) consolidation and reduced doses of anthracyclines. Patients and Methods Patients age 2 to 21 years with de novo APL confirmed by PML-RARα polymerase chain reaction were stratified as standard risk (SR) or high risk (HR) on the basis of diagnostic WBC count. All patients received all-trans retinoic acid (ATRA) during induction, each consolidation course, and maintenance. All patients received two cycles of ATO therapy during consolidation 1, an additional two (SR) or three (HR) consolidation courses that included high-dose cytarabine and anthracycline, and maintenance therapy comprising ATRA, oral methotrexate, and mercaptopurine. Results One hundred one patients (66 SR and 35 HR) were evaluable for outcome. The 3-year overall survival was 94%, and event-free survival (EFS) was 91%. For SR and HR patients with APL, the overall survival was 98% versus 86% ( P = .003), and EFS was 95% versus 83% ( P = .03), respectively. The EFS for SR patients in AAML0631 was noninferior to that of patients in the AIDA 0493 historical control, which used a significantly higher anthracycline dose and did not include ATO consolidation. Relapse risk for patients in AAML0631 from end consolidation 1 (after ATO treatment) was only 4% at 3 years and did not differ significantly between SR and HR patients. Conclusion ATO consolidation cycles were well tolerated in pediatric patients with APL and allowed significant reduction in cumulative anthracycline doses while maintaining excellent survival and a low relapse risk for both SR and HR patients with APL.


Assuntos
Antraciclinas/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Arsenicais/administração & dosagem , Leucemia Promielocítica Aguda/tratamento farmacológico , Óxidos/administração & dosagem , Adolescente , Adulto , Trióxido de Arsênio , Criança , Pré-Escolar , Quimioterapia de Consolidação , Citarabina/administração & dosagem , Intervalo Livre de Doença , Feminino , Estudo Historicamente Controlado , Humanos , Masculino , Mercaptopurina/administração & dosagem , Metotrexato/administração & dosagem , Adulto Jovem
10.
PLoS One ; 11(2): e0147183, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26845774

RESUMO

Ginsenoside compound K (CK), a rare ginsenoside originating from Panax Ginseng, has been found to possess unique pharmacological activities specifically as anti-cancers. However, the role of cytochrome P450s (CYPs) in the metabolism of CK is unclear. In this study, we screened the CYPs for the metabolism of CK in vitro using human liver microsomes (HLMs) or human recombinant CYPs. The results showed that CK inhibited the enzyme activities of CYP2C9 and CYP3A4 in the HLMs. The Km and Vmax values of CK were 84.20±21.92 µM and 0.28±0.04 nmol/mg protein/min, respectively, for the HLMs; 34.63±10.48 µM and 0.45±0.05 nmol/nmol P450/min, respectively, for CYP2C9; and 27.03±5.04 µM and 0.68±0.04 nmol/nmol P450/min, respectively, for CYP3A4. The IC50 values were 16.00 µM and 9.83 µM, and Ki values were 14.92 µM and 11.42µM for CYP2C9 and CYP3A4, respectively. Other human CYP isoforms, including CYP1A2, CYP2A6, CYP2D6, CYP2E1, and CYP2C19, showed minimal or no effect on CK metabolism. The results suggested that CK was a substrate and also inhibitors for both CYP2C9 and CYP3A4. Patients using CK in combination with therapeutic drugs that are substrates of CYP2C9 and CYP3A4 for different reasons should be careful, although the inhibiting potency of CK is much poorer than that of enzyme-specific inhibitors.


Assuntos
Antineoplásicos Fitogênicos/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Ginsenosídeos/metabolismo , Panax/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Citocromo P-450 CYP2C9/metabolismo , Inibidores do Citocromo P-450 CYP2C9/química , Inibidores do Citocromo P-450 CYP2C9/farmacologia , Citocromo P-450 CYP3A/metabolismo , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ginsenosídeos/química , Ginsenosídeos/farmacologia , Humanos , Técnicas In Vitro , Concentração Inibidora 50 , Cinética , Microssomos Hepáticos/enzimologia , Microssomos Hepáticos/metabolismo , Proteínas Recombinantes , Especificidade por Substrato
11.
PLoS One ; 9(11): e113819, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25427198

RESUMO

Meranzin hydrate (MH), an absorbed bioactive compound from the Traditional Chinese Medicine (TCM) Chaihu-Shugan-San (CSS), was first isolated in our laboratory and was found to possess anti-depression activity. However, the role of cytochrome P450s (CYPs) in the metabolism of MH was unclear. In this study, we screened the CYPs for the metabolism of MH in vitro by human liver microsomes (HLMs) or human recombinant CYPs. MH inhibited the enzyme activities of CYP1A2 and CYP2C19 in a concentration-dependent manner in the HLMs. The Km and Vmax values of MH were 10.3±1.3 µM and 99.1±3.3 nmol/mg protein/min, respectively, for the HLMs; 8.0±1.6 µM and 112.4±5.7 nmol/nmol P450/min, respectively, for CYP1A2; and 25.9±6.6 µM and 134.3±12.4 nmol/nmol P450/min, respectively, for CYP2C19. Other human CYP isoforms including CYP2A6, CYP2C9, CYP2D6, CYP2E1 and CYP3A4 showed minimal or no effect on MH metabolism. The results suggested that MH was simultaneously a substrate and an inhibitor of CYP1A2 and CYP2C9, and MH had the potential to perpetrate drug-drug interactions with other CYP1A2 and CYP2C19 substrates.


Assuntos
Antidepressivos/metabolismo , Cumarínicos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Microssomos Hepáticos/metabolismo , Extratos Vegetais/metabolismo , Antidepressivos/farmacologia , Cumarínicos/farmacologia , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2C19/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Extratos Vegetais/farmacologia
12.
Int J Cancer ; 134(4): 799-810, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23922098

RESUMO

Glycine N-methyltransferase (GNMT) is a folate binding protein commonly diminished in human hepatoma yet its role in tumor development remains to be established. GNMT binds to methylfolate but is also inhibited by it; how such interactions affect human carcinogenesis is unclear. We postulated that GNMT plays a role in folate-dependent methyl group homeostasis and helps maintain genome integrity by promoting nucleotide biosynthesis and DNA repair. To test the hypothesis, GNMT was over-expressed in GNMT-null cell lines cultured in conditions of folate abundance or restriction. The partitioning of folate dependent 1-carbon groups was investigated using stable isotopic tracers and GC/MS. DNA damage was assessed as uracil content in cell models, as well as in Gnmt wildtype (Gnmt(+/+)), heterozygote (Gnmt(+/-)) and knockout (Gnmt(-/-)) mice under folate deplete, replete, or supplementation conditions. Our study demonstrated that GMMT 1) supports methylene-folate dependent pyrimidine synthesis; 2) supports formylfolate dependent purine syntheses; 3) minimizes uracil incorporation into DNA when cells and animals were exposed to folate depletion; 4) translocates into nuclei during prolonged folate depletion. In conclusion, loss of GNMT impairs nucleotide biosynthesis. Over-expression of GNMT enhances nucleotide biosynthesis and improves DNA integrity by reducing uracil misincorporation in DNA both in vitro and in vivo. To our best knowledge, the role of GNMT in folate dependent 1-carbon transfer in nucleotide biosynthesis has never been investigated. The present study gives new insights into the underlying mechanism by which GNMT can participate in tumor prevention/suppression in humans.


Assuntos
Carcinoma Hepatocelular/patologia , Dano ao DNA , Ácido Fólico/farmacologia , Glicina N-Metiltransferase/fisiologia , Hepatócitos/patologia , Neoplasias Hepáticas/patologia , Fígado/patologia , Adenosina/metabolismo , Animais , Radioisótopos de Carbono , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Metilação de DNA , Suplementos Nutricionais , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Hepatócitos/metabolismo , Homocisteína/metabolismo , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Camundongos , Camundongos Knockout , Antígenos de Histocompatibilidade Menor , Transporte Proteico , Purinas/metabolismo , Pirimidinas/metabolismo , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo , Tetra-Hidrofolatos , Uracila/metabolismo
13.
J Agric Food Chem ; 61(20): 4839-49, 2013 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-23663050

RESUMO

Human endothelial progenitor cells (EPCs) play crucial roles in the prevention of ischemic injury via neovasculogenesis. Frequent garlic consumption is reportedly associated with a low incidence of cardiovascular diseases (CVD). However, the molecular mechanisms by which garlic extracts, including diallyl disulfide (DADS) and diallyl trisulfide (DATS), exert an effect on neovasculogenesis have not been elucidated yet. The current study investigated the effects of these organosulfur compounds on neovasculogenesis by using vascular tube formation assay, Western blotting assay, real-time polymerase chain reaction (RT-PCR), and immunohistochemical (IHC) staining assays in both in vitro and in vivo models. The current study demonstrates that DADS and DATS dose-dependently enhance the neovasculogenesis of human EPCs in vitro. The mechanism of actions included the up-regulation of the c-kit protein, as well as the phosphorylation (i.e., activation) of the Akt and ERK 1/2 signaling molecules in human EPCs. Furthermore, DATS suppressed the expression of microRNA (miR) 221 in vitro. In a mouse xenograft model of neovasculogenesis, DATS consumption induced the formation of new blood vessels at a dosage of 10 mg/kg of body weight/day. It is suggested that garlic consumption enhances neovasculogenesis in human EPCs and thereby probably exerts a preventive effect against ischemic injuries.


Assuntos
Compostos Alílicos/farmacologia , Células Endoteliais/fisiologia , Alho/química , MicroRNAs/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sulfetos/farmacologia , Animais , Células Cultivadas , Dissulfetos/farmacologia , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/transplante , Feminino , Expressão Gênica/efeitos dos fármacos , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transplante de Células-Tronco , Células-Tronco/efeitos dos fármacos , Células-Tronco/fisiologia
14.
Mol Med ; 18: 423-32, 2012 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-22193356

RESUMO

Methionine S-adenosyltransferase (MAT) catalyzes the only reaction that produces the major methyl donor in mammals. Low-dose methotrexate is the most commonly used disease-modifying antirheumatic drug in human rheumatic conditions. The present study was conducted to test the hypothesis that methotrexate inhibits MAT expression and activity in vitro and in vivo. HepG2 cells were cultured under folate restriction or in low-dose methotrexate with and without folate or methionine supplementation. Male C57BL/6J mice received methotrexate regimens that reflected low-dose clinical use in humans. S-adenosylmethionine and MAT genes, proteins and enzyme activity levels were determined. We found that methionine or folate supplementation greatly improved S-adenosylmethionine in folate-depleted cells but not in cells preexposed to methotrexate. Methotrexate but not folate depletion suppressed MAT genes, proteins and activity in vitro. Low-dose methotrexate inhibited MAT1A and MAT2A genes, MATI/II/III proteins and MAT enzyme activities in mouse tissues. Concurrent folinate supplementation with methotrexate ameliorated MAT2A reduction and restored S-adenosylmethionine in HepG2 cells. However, posttreatment folinate rescue failed to restore MAT2A reduction or S-adenosylmethionine level in cells preexposed to methotrexate. Our results provide both in vitro and in vivo evidence that low-dose methotrexate inhibits MAT genes, proteins, and enzyme activity independent of folate depletion. Because polyglutamated methotrexate stays in the hepatocytes, if methotrexate inhibits MAT in the liver, then the efficacy of clinical folinate rescue with respect to maintaining hepatic S-adenosylmethionine synthesis and normalizing the methylation reactions would be limited. These findings raise concerns on perturbed methylation reactions in humans on low-dose methotrexate. Future studies on the clinical physiological consequences of MAT inhibition by methotrexate and the potential benefits of S-adenosylmethionine supplementation on methyl group homeostasis in clinical methotrexate therapies are warranted.


Assuntos
Antirreumáticos/farmacologia , Metionina Adenosiltransferase/antagonistas & inibidores , Metotrexato/farmacologia , Animais , Dactinomicina , Dexametasona , Inibidores Enzimáticos/farmacologia , Ácido Fólico/metabolismo , Ácido Fólico/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Masculino , Metionina/farmacologia , Metionina Adenosiltransferase/genética , Metionina Adenosiltransferase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , S-Adenosilmetionina/metabolismo
15.
Arthritis Res Ther ; 7(6): R1254-62, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16277678

RESUMO

Previously we observed strong and consistent associations between vitamin B6 status and several indicators of inflammation in patients with rheumatoid arthritis. Clinical indicators, including the disability score, the length of morning stiffness, and the degree of pain, and biochemical markers, including the erythrocyte sedimentation rate and C-reactive protein levels, were found to be inversely correlated with circulating vitamin B6 levels. Such strong associations imply that impaired vitamin B6 status in these patients results from inflammation. In the present study we examined whether inflammation directly alters vitamin B6 tissue contents and its excretion in vivo. A cross-sectional case-controlled human clinical trial was performed in parallel with experiments in an animal model of inflammation. Plasma and erythrocyte and pyridoxal 5'-phosphate concentrations, urinary 4-pyridoxic acid excretion, and the activity coefficient of erythrocyte aspartate aminotransferase were compared between patients and healthy subjects. Adjuvant arthritis was induced in rats for investigating hepatic and muscle contents as well as the urinary excretion of vitamin B6 during acute and chronic inflammation. Patients with rheumatoid arthritis had low plasma pyridoxal 5'-phosphate compared with healthy control subjects, but normal erythrocyte pyridoxal 5'-phosphate and urinary 4-pyridoxic acid excretion. Adjuvant arthritis in rats did not affect 4-pyridoxic acid excretion or muscle storage of pyridoxal 5'-phosphate, but it resulted in significantly lower pyridoxal 5'-phosphate levels in circulation and in liver during inflammation. Inflammation induced a tissue-specific depletion of vitamin B6. The low plasma pyridoxal 5'-phosphate levels seen in inflammation are unlikely to be due to insufficient intake or excessive vitamin B6 excretion. Possible causes of decreased levels of vitamin B6 are discussed.


Assuntos
Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Inflamação/metabolismo , Deficiência de Vitamina B 6/metabolismo , Vitamina B 6/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Artrite Experimental/complicações , Artrite Experimental/fisiopatologia , Artrite Reumatoide/complicações , Artrite Reumatoide/fisiopatologia , Estudos Transversais , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/complicações , Inflamação/fisiopatologia , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Ratos , Ratos Endogâmicos Lew , Deficiência de Vitamina B 6/complicações , Deficiência de Vitamina B 6/fisiopatologia
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