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1.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731488

RESUMO

This study synthesized a novel oat ß-glucan (OBG)-Cr(III) complex (OBG-Cr(III)) and explored its structure, inhibitory effects on α-amylase and α-glucosidase, and hypoglycemic activities and mechanism in vitro using an insulin-resistant HepG2 (IR-HepG2) cell model. The Cr(III) content in the complex was found to be 10.87%. The molecular weight of OBG-Cr(III) was determined to be 7.736 × 104 Da with chromium ions binding to the hydroxyl groups of OBG. This binding resulted in the increased asymmetry and altered spatial conformation of the complex along with significant changes in morphology and crystallinity. Our findings demonstrated that OBG-Cr(III) exhibited inhibitory effects on α-amylase and α-glucosidase. Furthermore, OBG-Cr(III) enhanced the insulin sensitivity of IR-HepG2 cells, promoting glucose uptake and metabolism more efficiently than OBG alone. The underlying mechanism of its hypoglycemic effect involved the modulation of the c-Cbl/PI3K/AKT/GLUT4 signaling pathway, as revealed by Western blot analysis. This research not only broadened the applications of OBG but also positioned OBG-Cr(III) as a promising Cr(III) supplement with enhanced hypoglycemic benefits.


Assuntos
Cromo , Hipoglicemiantes , alfa-Glucosidases , beta-Glucanas , Humanos , Cromo/química , Cromo/farmacologia , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/síntese química , beta-Glucanas/química , beta-Glucanas/farmacologia , Células Hep G2 , alfa-Glucosidases/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , Resistência à Insulina , Glucose/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Avena/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química
2.
J Med Imaging (Bellingham) ; 10(2): 024001, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36875637

RESUMO

Purpose: Segmentation of vascular structures in preoperative computed tomography (CT) is a preliminary step for computer-assisted endovascular navigation. It is a challenging issue when contrast medium enhancement is reduced or impossible, as in the case of endovascular abdominal aneurysm repair for patients with severe renal impairment. In non-contrast-enhanced CTs, the segmentation tasks are currently hampered by the problems of low contrast, similar topological form, and size imbalance. To tackle these problems, we propose a novel fully automatic approach based on convolutional neural network. Approach: The proposed method is implemented by fusing the features from different dimensions by three kinds of mechanisms, i.e., channel concatenation, dense connection, and spatial interpolation. The fusion mechanisms are regarded as the enhancement of features in non-contrast CTs where the boundary of aorta is ambiguous. Results: All of the networks are validated by three-fold cross-validation on our dataset of non-contrast CTs, which contains 5749 slices in total from 30 individual patients. Our methods achieve a Dice score of 88.7% as the overall performance, which is better than the results reported in the related works. Conclusions: The analysis indicates that our methods yield a competitive performance by overcoming the above-mentioned problems in most general cases. Further, experiments on our non-contrast CTs demonstrate the superiority of the proposed methods, especially in low-contrast, similar-shaped, and extreme-sized cases.

3.
Molecules ; 27(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36144522

RESUMO

The novel biochanin A-chromium(III) complex was synthesized by chelating chromium with biochanin A (BCA). The structure of the complex was determined and the complex ([CrBCA3]) was composed of chromium(III) and three ligands, and the chromium content was 55 µg/mg. The hypoglycemic activity of the complex was studied in db/db mice and C57 mice. The sub-acute toxicity test of the complex was carried out by the maximum limit method in KM mice. The hypoglycemic activity showed that the complex could reduce the weight of db/db mice and lower the fasting blood glucose and random blood glucose levels. The complex also improved the organ index, oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) results of db/db mice, and some of the indicators were similar to those of the positive control group after treatment with the complex. The histopathology study showed significant improvements in the liver, kidney, pancreas and skeletal muscle compared with the diabetes model group. The complex also showed a significant improvement in serum biochemical indices and antioxidant enzyme activities, as well as glycogen levels. The sub-acute toxicity study showed that the complex did not cause death or any dangerous symptoms during the study. In addition, the sub-acute toxicity study showed that the complex had no significant effect on the serum biochemical indices, antioxidant capacity and organs of normal mice. This study showed that [CrBCA3] had good hypoglycemic activity in vivo and had no sub-acute toxicity. This work provides an important reference for the development of functional hypoglycemic foods or drugs.


Assuntos
Diabetes Mellitus Experimental , Insulinas , Animais , Antioxidantes/uso terapêutico , Glicemia , Cromo/química , Cromo/toxicidade , Diabetes Mellitus Experimental/patologia , Genisteína , Glicogênio , Hipoglicemiantes/química , Insulina/uso terapêutico , Insulinas/uso terapêutico , Camundongos
4.
Molecules ; 27(16)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36014535

RESUMO

Soybean is widely used as a kind of bean for daily consumption. Chickpea is increasingly utilised because of its good healthcare function. At present, using chickpeas could have better results than soybeans in some areas. Previous studies of the two legumes focused on certain components and failed to fully reveal the differences between the two legumes. Thus, understanding the comprehensive similarities and differences between the two legumes is necessary to apply and develop these legumes effectively. In this study, we performed a UPLC-ESI-MS/MS-based widely targeted metabolomics analysis on two legumes. A total of 776 metabolites (including primary metabolites and secondary metabolites) were detected, which were divided into more than a dozen broad categories. The differential analysis of these metabolites showed that there were 480 metabolites with significant differences in relative contents between the two legumes. Compared with soybean, the expression of 374 metabolites of chickpea was down-regulated and that of 106 metabolites was up-regulated. The metabolic pathway analysis showed significant differences in the flavonoids biosynthesis, phenylpropanoid biosynthesis, linoleic acid metabolism and alkaloid biosynthesis between the two legumes. The advantages and applicability of the two kinds of legumes were confirmed through the analysis of anti-diabetic components. Moreover, some novel compounds (with contents higher than that of soybean) with hypoglycaemic activity were found in chickpea. This study provides an important reference for the in-depth study and comparative application of soybean and chickpea.


Assuntos
Cicer , Diabetes Mellitus , Fabaceae , Metabolômica/métodos , Glycine max , Espectrometria de Massas em Tandem
5.
Nat Metab ; 4(1): 106-122, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35075301

RESUMO

The link between branched-chain amino acids (BCAAs) and obesity has been known for decades but the functional role of BCAA metabolism in white adipose tissue (WAT) of obese individuals remains vague. Here, we show that mice with adipose tissue knockout of Bcat2, which converts BCAAs to branched-chain keto acids (BCKAs), are resistant to high-fat diet-induced obesity due to increased inguinal WAT browning and thermogenesis. Mechanistically, acetyl-CoA derived from BCKA suppresses WAT browning by acetylation of PR domain-containing protein 16 (PRDM16) at K915, disrupting the interaction between PRDM16 and peroxisome proliferator-activated receptor-γ (PPARγ) to maintain WAT characteristics. Depletion of BCKA-derived acetyl-CoA robustly prompts WAT browning and energy expenditure. In contrast, BCKA supplementation re-establishes high-fat diet-induced obesity in Bcat2 knockout mice. Moreover, telmisartan, an anti-hypertension drug, significantly represses Bcat2 activity via direct binding, resulting in enhanced WAT browning and reduced adiposity. Strikingly, BCKA supplementation reverses the lean phenotype conferred by telmisartan. Thus, we uncover the critical role of the BCAA-BCKA axis in WAT browning.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Proteínas de Ligação a DNA/metabolismo , Cetoácidos/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Animais , Sítios de Ligação , Temperatura Corporal , Proteínas de Ligação a DNA/genética , Dieta Hiperlipídica , Metabolismo Energético , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Camundongos , Camundongos Knockout , Modelos Moleculares , Obesidade/etiologia , Obesidade/metabolismo , PPAR gama/metabolismo , Ligação Proteica , Relação Estrutura-Atividade , Termogênese , Transaminases/antagonistas & inibidores , Transaminases/química , Transaminases/metabolismo , Fatores de Transcrição/genética
6.
J Trace Elem Med Biol ; 62: 126606, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32650064

RESUMO

BACKGROUND: In this study, chromium (III) complex was synthesized from genistein (GEN) which had good hypoglycemic activity and inorganic chromium (III) element, and its hypoglycemic activity and sub-acute toxicity were studied. METHODS: The genistein-chromium (III) complex was synthesized by chelating chromium with genistein in ethanol and its structure was determined by LC-MS, atomic absorption spectroscopy, UV-vis spectroscopy, infrared spectroscopy, elemental and thermodynamic analysis. The anti-diabetic activity of the complex was assessed in db/db mice and C57 mice by daily oral gavage for 4 weeks. The sub-acute toxicity test was carried out on KM mice with this complex. RESULTS: The molecular structure of this complex was inferred as a complex [CrGEN3] formed by three ligands and one chromium element. The complex could significantly improve the body weight of db/db mice, fasting blood glucose, random blood glucose, organ index, glycogen levels and the performance of OGTT (Oral Glucose Tolerance Test) and ITT (Insulin Tolerance Test) in db/db mice (p < 0.05). The morphology of liver, kidney, pancreas and skeletal muscle also had obviously improvement and repairment. Effects on serum indices and antioxidant enzymes activities of db/db mice showed that the serum profiles and antioxidant ability of complex group had significant improvement compared with the diabetic control group (p < 0.05 or p < 0.01), and some indices even returned to normal levels. In addition, this complex did not produce any hazardous symptoms or deaths in sub-acute toxicity test. High dose of [CrGEN3] had no significant influence on serum indices and antioxidant capacity in normal mice, and the organ tissues maintained organized and integrity in the sub-acute toxicity study. CONCLUSION: The study of the genistein-chromium (III) complex showed that the complex had good hypoglycemic activity in vivo, and did not have the potential toxicity. These results would provide an important reference for the development of functional hypoglycemic foods or pharmaceuticals.


Assuntos
Cromo/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Genisteína/uso terapêutico , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Cromatografia Líquida , Teste de Tolerância a Glucose , Hipoglicemiantes/uso terapêutico , Espectrometria de Massas , Camundongos
7.
Drug Des Devel Ther ; 14: 977-992, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184567

RESUMO

PURPOSE: This study aimed to synthesize twin drugs from cinnamic acid compounds, caffeic acid (CFA) and ferulic acid (FLA), which can antagonize endothelin-1 (ET-1) with telmisartan through ester bonds. Moreover, the antihypertensive effect of telmisartan and its influence on blood pressure variability (BPV) were enhanced, and the bioavailability of caffeic acid and ferulic acid was improved. METHODS: Six twin drugs, which were the target compounds, were synthesized. Hypertensive rats (SHR) and conscious sinoaortic-denervated (SAD) rats were spontaneously used as models for pharmacodynamic research to study the antihypertensive efficacy of these twin drugs. Wistar rats were employed as pharmacokinetic research models to investigate the pharmacokinetics of the target compounds via intragastric administration. Cellular pharmacodynamic research was also conducted on the antagonistic action on Ang II-AT1, ETA and ETB receptor. RESULTS: Compound 1a was determined as the best antihypertensive twin drug and thus was further studied for its effect on BPV. Compared with that of telmisartan, the antihypertensive effect of compound 1a was improved (p<0.05), and the BPV was reduced (p<0.05). The bioavailability of caffeic acid and ferulic acid after hydrolysis from twin drugs could be increased to varying degrees, and the differences of the main pharmacokinetic parameters among the different forms of caffeic acid and ferulic acid were statistically significant (p<0.05 or p<0.01). Compound 1a had the best antagonistic effect on the Ang II-AT1 receptor. However, the IC50 of Lps-2 was still two orders of magnitude higher than that of the positive drug telmisartan. Hence, the twin drugs worked by metabolizing and regenerating telmisartan and caffeic acid or ferulic acid in the body. CONCLUSION: The synthesized twin drugs improved telmisartan's antihypertensive effects, significantly decreased BPV in SAD rats and increased the bioavailability of caffeic acid and ferulic acid. This study serves as a basis for the development of new angiotensin receptor blocker (ARB) in the future and a reference for the development of new drugs to antagonize ET-1.


Assuntos
Antagonistas de Receptores de Angiotensina/farmacologia , Anti-Hipertensivos/farmacologia , Ácidos Cafeicos/farmacologia , Ácidos Cumáricos/farmacologia , Receptor Tipo 1 de Angiotensina/metabolismo , Telmisartan/farmacologia , Antagonistas de Receptores de Angiotensina/síntese química , Antagonistas de Receptores de Angiotensina/química , Animais , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/química , Pressão Sanguínea/efeitos dos fármacos , Ácidos Cafeicos/química , Ácidos Cumáricos/química , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Estrutura Molecular , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Relação Estrutura-Atividade , Telmisartan/química
8.
J Cancer ; 9(12): 2183-2190, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29937938

RESUMO

The present study aimed to investigate whether cell lines from human gastric and liver cancers respond differently toward cantharidin (CTD) and norcantharidin (NCTD) than other types of cancer cells. We first established the half maximal inhibitory concentrations (IC50s) of CTD for a large panel of cancer cell lines representing the 12 major types of human cancers and the mode of cell death induced by the two compounds. We next compared the growth inhibitory effects as well as the corresponding modes of action of CTD and NCTD. The IncuCyte ZOOM system was used as a semi-high throughput means to define IC50s and 90% inhibitory doses (IC90s) as a reference for the maximal tolerable doses (MTDs) for the two compounds in 72 cancer cell lines. Classical clonogenic survival assay was used to assess the anti-proliferative effect of CTD on selected cell lines of interest. In addition, DNA content-based flow was used to interrogate the modes of cell death following CTD or NCTD exposure. The results of these experiments led to several findings. 1). Cell lines representing hepatocellular carcinomas (HCCs) and cholangiocarcinomas (CCs) were among the most sensitive toward CTD, consistent with the previous clinical study of this compound and its source of origin, Mylabris. 2). Among the individual cell lines of a given cancer types, the sensitivity trends for CTD and NCTD did not exhibit a good correlation. 3) CTD and NCTD caused distinctive cytotoxic effects on HepG2 cells. Specifically, while a cytostatic effect is the primary cause of growth inhibition of CTD, cytotoxic effect is the main contributing factor for the growth inhibition of NTCD. These results indicate that liver cancer cell lines are among the most sensitive to CTD and that CTD and NCTD exhibit their effects through distinct mechanisms.

9.
Free Radic Biol Med ; 124: 51-60, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-29803806

RESUMO

PURPOSE: Excessive oxidative stress (OS) leads to cellular dysfunctions and cell death and constitutes a major cause of male infertility. However, the etiologies of increased reactive oxygen species (ROS) in male infertility is not fully understood. One major limitation is the lack of an in vivo imaging system that can be used to effectively study the impact of excessive ROS in the testis. Recently, we discovered that the hepatocellular carcinoma reporter (HCR) mice previously generated in our laboratory also expressed luciferase in the spermatids of the testis. The goal of the current study is to use the HCR mice to detect OS in the testis and to investigate the potential use of this new system in studying OS-induced male infertility. EXPERIMENTAL DESIGN: Bioluminescence imaging (BLI) was performed in HCR mice that were treated with peroxy caged luciferin-1 (PCL-1), an OS reporter, to establish a new mouse model for in vivo monitoring of the OS status inside the male reproductive tract. Subsequently, the effect of acetaminophen (APAP) overdose on the OS inside the testis and male fertility were determined. Lastly, APAP was co-administered with glutathione, an antioxidant reagent, to test if the HCR mice can serve as a model for the effective and rapid assessment of the potency of individual agents in modifying the OS inside the mouse testis. RESULTS: The OS level in the testis in the HCR mice was readily detected by BLI. The use of this new model led to the discovery that APAP caused a sudden rise of OS in the testis and was a potent toxicant for the male reproductive system. Moreover, administration of glutathione was effective in preventing the APAP-induced elevation of OS and in ameliorating all of the OS-induced anomalies in the testis. CONCLUSIONS: The HCR mice represent an excellent model for monitoring OS change in the mouse testis by real time BLI. APAP is a potent male reproductive toxicant and APAP-treated mice represent a valid model for OS-induced male infertility. This model can be used to study OS-induced damage in male reproductive tract and in assessing the effects of therapeutic agents on the relative levels of OS and male fertility.


Assuntos
Acetaminofen/farmacologia , Carcinoma Hepatocelular/complicações , Infertilidade Masculina/patologia , Substâncias Luminescentes/química , Imagem Óptica/métodos , Estresse Oxidativo , Testículo/patologia , Analgésicos não Narcóticos/farmacologia , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Modelos Animais de Doenças , Glutationa/metabolismo , Infertilidade Masculina/diagnóstico por imagem , Infertilidade Masculina/etiologia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Medições Luminescentes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Testículo/diagnóstico por imagem , Testículo/efeitos dos fármacos
10.
Plant Mol Biol ; 79(4-5): 375-91, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22581008

RESUMO

Harpin proteins secreted by phytopathogenic bacteria have been shown to activate the plant defense pathway, which involves transduction of a hydrogen peroxide (H(2)O(2)) signal generated in the apoplast. However, the way in which harpins are recognized in the pathway and what role the apoplastic H(2)O(2) plays in plant defenses are unclear. Here, we examine whether the cellular localization of Hpa1(Xoo), a harpin protein produced by the rice bacterial leaf blight pathogen, impacts H(2)O(2) production and pathogen resistance in Arabidopsis thaliana. Transformation with the hpa1 (Xoo) gene and hpa1 (Xoo) fused to an apoplastic localization signal (shpa1 (Xoo)) generated h pa1 (Xoo)- and sh pa1 (Xoo)-expressing transgenic A . t haliana (HETAt and SHETAt) plants, respectively. Hpa1(Xoo) was associated with the apoplast in SHETAt plants but localized inside the cell in HETAt plants. In addition, Hpa1(Xoo) localization accompanied H(2)O(2) accumulation in both the apoplast and cytoplasm of SHETAt plants but only in the cytoplasm of HETAt plants. Apoplastic H(2)O(2) production via nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) located in the plasma membrane is a common feature of plant defenses. In SHETAt plants, H(2)O(2) was generated in apoplasts in a NOX-dependent manner but accumulated to a greater extent in the cytoplasm than in the apoplast. After being applied to the wild-type plant, Hpa1(Xoo) localized to apoplasts and stimulated H(2)O(2) production as in SHETAt plants. In both plants, inhibiting apoplastic H(2)O(2) generation abrogated both cytoplasmic H(2)O(2) accumulation and plant resistance to bacterial pathogens. These results suggest the possibility that the apoplastic H(2)O(2) is subject to a cytoplasmic translocation for participation in the pathogen defense.


Assuntos
Arabidopsis/metabolismo , Arabidopsis/microbiologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Arabidopsis/genética , Proteínas da Membrana Bacteriana Externa/genética , Transporte Biológico Ativo , Membrana Celular/metabolismo , Citoplasma/metabolismo , Espaço Extracelular/metabolismo , Genes Bacterianos , Peróxido de Hidrogênio/metabolismo , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Xanthomonas/genética , Xanthomonas/metabolismo , Xanthomonas/patogenicidade
11.
Sheng Wu Gong Cheng Xue Bao ; 19(1): 74-80, 2003 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15969040

RESUMO

Cis-1,2-dihydroxycyclohexa-3,5-diene (DHCD) can be used as a valuable chiral intermediates for applications in pharmaceuticals, aerospace, electrical and fine chemical industries. By on-line detection of toluene dioxygenase (TDO) activity in whole recombinant Escherichia coli JM109 (pKST11) cells that harbored TDO gene under a tac promoter, effects of IPTG and various benzene addition strategies on bioransformation of benzene to DHCD were investigated. When IPTG was used at the beginning of fermentation, the growth of cells was inhibited and TDO activity only maintained for 4 hours while same experiments with addition of IPTG at 6h or 8h generated TDO activity for 18 hours. Suitable induction time for IPTG was in the cell logarithmic growth phase and 0.5 mmol/L IPTG was sufficient for inducing maximum TDO activities. Benzene strongly inhibited the activity of TDO which catalyses the conversion of benzene to DHCD. It was found that both cell growth and TDO activity was remarkably inhibited by feeding of benzene vapor, only 7.5 g/L DHCD was obtained. While the benzene inhibition effect was ameliorated by two-liquid phase culture fermentation in which liquid paraffin was used as second phase in the broth. Using different initial ratios of paraffin to benzene in fed-batch culture, DHCD contents were increased to 22.6 g/L, which was 3-fold more compared with that in benzene vapor culture. A further improvement of DHCD production was achieved when the mixture of liquid paraffin and benzene was added continuously by peristaltic pump, the DHCD contents were increased to a final concentration of 36.8 g/L. It was proven that the key to improving DHCD production by recombinants is to prolong TDO activity in cells, which can be achieved by using suitable addition benzene strategies.


Assuntos
Benzeno/metabolismo , Cicloexanóis/metabolismo , Escherichia coli/metabolismo , Escherichia coli/genética , Fermentação/fisiologia , Oxigenases/genética , Oxigenases/metabolismo
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