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1.
BMC Cancer ; 23(1): 59, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650455

RESUMO

BACKGROUND: Saroglitazar is a novel PPAR-α/γ agonist with predominant PPAR-α activity. In various preclinical models, saroglitazar has been shown to prevent & reverse symptoms of NASH. In view of these observations, and the fact that NASH is a progressive disease leading to HCC, we hypothesized that saroglitazar may prevent the development of HCC in rodents. METHODS: HCC was induced in C57BL/6 mice by a single intraperitoneal injection of 25 mg/kg diethylnitrosamine (DEN) at the age of 4 weeks and then feeding the animal a choline-deficient, L-amino acid- defined, high-fat diet (CDAHFD) for the entire study duration. Eight weeks after initiation of CDAHFD, saroglitazar (1 and 3 mg/kg) treatment was started and continued for another 27 weeks. RESULTS: Saroglitazar treatment significantly reduced the liver injury markers (serum ALT and AST), reversed hepatic steatosis and decreased the levels of pro-inflammatory cytokines like TNF-α in liver. It also resulted in a marked increase in serum adiponectin and osteopontin levels. All disease control animals showed hepatic tumors, which was absent in saroglitazar (3 mg/kg)- treatment group indicating 100% prevention of hepatic tumorigenesis. This is the first study demonstrating a potent PPARα agonist causing suppression of liver tumors in rodents, perhaps due to a strong anti-NASH activity of Saroglitazar that overrides its rodent-specific peroxisome proliferation activity. CONCLUSION: The data reveals potential of saroglitazar for chemoprevention of hepatocellular carcinoma in patients with NAFLD/NASH.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/prevenção & controle , Colina , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/prevenção & controle , Injeções Intraperitoneais , Dieta Hiperlipídica/efeitos adversos , Aminoácidos , Receptores Ativados por Proliferador de Peroxissomo , Camundongos Endogâmicos C57BL , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Modelos Animais de Doenças
2.
Interdiscip Toxicol ; 12(1): 7-14, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32189982

RESUMO

Rosuvastatin, a second generation 3-Hydroxy-3-Methyl Glutaryl Coenzyme-A reductase inhibitor, is widely used for the management of hypercholesterolemia. Rosuvastatin ethanolamine, developed by Cadila Healthcare Ltd., is a novel, chemically stable, and pharmaceutically acceptable salt, having better physiochemical properties than commercially available Rosuvastatin salt. The objective of the present study is to evaluate safety, tolerability, and toxicokinetic profile of novel salt. Therefore, four weeks repeated dose oral (gavage) toxicity and toxicokinetic study of Rosuvastatin ethanolamine was carried out. The drugs were administered once daily at salt corrected dose of 15, 40, and 100 mg/kg for four weeks. No signs of toxicity were observed during repeated (four weeks) oral administrations of Rosuvastatin ethanolamine in rats up to 40 mg/kg. Single male mortality was observed at 100 mg/kg dose. Microscopy finding in liver was minimal to mild bile ductular proliferation, single cell necrosis, and hepatocellular vacuolation of cytoplasm with associated statistically significant serum elevation of transaminase enzymes; AST, ALT, ALP, and/or liver functional marker; total bilirubin with at ≥40 mg/kg. The systemic exposures (AUC0-24 and Cmax) were not markedly different between males and females, or between the administration periods (except high dose, where exposure on day 28 was approximately 2 to 3 fold higher than that of day 1. In conclusion, Rosuvastatin ethanolamine exhibited toxicities to liver as the target organ at ≥40 mg/kg in this study. These adverse effects with associated exposures should be taken into consideration for the future assessing of potential Rosuvastatin toxicities.

3.
Interdiscip Toxicol ; 12(3): 149-156, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32210704

RESUMO

Estrous cycle is a repetitive phenomenon occurring during the reproductive life of a female dog. The duration of the canine estrous cycle is considerably longer than one in the most of the other animals and is broadly grouped into follicular phase (proestrus and estrus), luteal phase (diestrus) and non-seasonal anestrus. Dogs in the same stage of cycle can be inadvertently assigned to same group during routine safety and metabolic studies leading to possible erroneous interpretation of test-item related effects. This retrospective analysis was conducted by analyzing data of 86 female beagle dogs from control/placebo treated groups to correlate any possible effect of estrous stages with electrocardiography, clinical pathology and ovarian weight. Different estrous cycle stages of beagles were confirmed histologically by evaluating ovary, uterus, vagina and mammary glands. The incidence of beagles in diestrus was the highest, followed by anestrus, proestrus and estrus. No significant effect was noticed on heart rate, P-A, P-D, RR, QRS and QT intervals across different stages of estrous cycle. However, significantly higher PQ (PR) interval in dogs in proestrus stage was observed compared to dogs in anestrus and estrus. Marginally higher WBCs, neutrophils, lymphocytes, RBCs, hemoglobin, AST and lower hematocrit, lipid profile (total cholesterol, HDL, LDL, triglycerides), ALP level was evident in estrous period. Relative ovary weight was significantly higher in dogs in diestrus stage. Considering these results, one may need to exercise caution while interpreting experimental data from female beagle dogs.

4.
Ultrason Sonochem ; 52: 193-204, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30514598

RESUMO

In this work, sonication (20-kHz) was conducted to assist the biosorption of phenolics from blueberry pomace extracts by brewery waste yeast biomass. The adsorption capacity of yeast increased markedly under ultrasonic fields. After sonication at 394.2 W/L and 40 °C for 120 min, the adsorption capacity was increased by 62.7% compared with that under reciprocating shaking. An artificial neural network was used to model and visualize the effects of different parameters on yeast biosorption capacity. Both biosorption time and acoustic energy density had positive influences on yeast biosorption capacity, whereas no clear influence of temperature on biosorption process was observed. Regarding the mechanism of ultrasound-enhanced biosorption process, the amino and carboxyl groups in yeast were considered to be associated with the yeast biosorption property. Meanwhile, ultrasound promoted the decline of the structure order of yeast cells induced by phenolic uptake. The interactions between yeast cells and phenolics were also affected by the structures of phenolics. Moreover, the mass transfer process was simulated by a surface diffusional model considering the ultrasound-induced yeast cell disruption. The modeling results showed that the external mass transfer coefficient in liquid phase and the surface diffusion coefficient under sonication at 394.2 W/L and 40 °C were 128.5% and 74.3% higher than that under reciprocating shaking, respectively.


Assuntos
Mirtilos Azuis (Planta)/química , Frutas/química , Fenóis/química , Saccharomyces cerevisiae/química , Sonicação , Resíduos , Adsorção , Cinética
5.
Xenobiotica ; 49(6): 698-707, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29873579

RESUMO

Pharmacokinetics of voriconazole, an anti-fungal agent, was determined in collagen-induced arthritic (CIA) and healthy DBA/1J mice. CIA was confirmed in DBA/1J mice by clinical scoring and histological analysis. In vivo oral pharmacokinetic study (3 mg/kg) and in vitro stability assessment in liver microsomes were performed in CIA vs. healthy DBA/1J mice. Additionally, hepatic portal vein cannulated (HPVC) CIA and healthy mice were used to clarify the role of gut first-pass effect. Voriconazole/N-oxide metabolite was measured in plasma and in vitro samples using liquid chromatography tandem-mass spectrometry method. Voriconazole exposure was reduced in CIA by 27% as compared to healthy mice. Formation of voriconazole N-oxide was higher in CIA mice as evidenced by higher molar Cmax ratio (i.e. metabolite/parent) of 2.08 vs. 1.66 in healthy mice. Because voriconazole was stable in microsomes, involvement of presystemic gut metabolism was suspected for decreased voriconazole exposure and formation of higher molar ratio of metabolite. HPVC work revealed higher formation of voriconazole N-oxide in CIA relative to healthy mice resulting in Cmax/AUC ratios of 0.41/0.54 and 0.08/0.17, respectively, confirming first-pass effect. The findings may have implications in the clinical therapy of arthritis patients who are concomitantly given voriconazole for the management of fungal infections.


Assuntos
Antifúngicos/farmacocinética , Artrite Experimental/metabolismo , Voriconazol/farmacocinética , Animais , Antifúngicos/química , Artrite Experimental/complicações , Masculino , Camundongos Endogâmicos DBA , Micoses/complicações , Micoses/tratamento farmacológico , Voriconazol/química
6.
Can J Physiol Pharmacol ; 96(6): 587-596, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29406832

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is often associated with obesity and type 2 diabetes. Coagonists of glucagon-like peptide-1 receptor (GLP-1R) and glucagon receptor (GCGR) are under clinical investigation for the treatment of obesity and type 2 diabetes. In this study, we have demonstrated the effect of a balanced coagonist in the treatment of NAFLD using mouse models. GLP-1R agonist exendin-4, glucagon, and coagonist (Aib2 C24 chimera2) were administered to C57BL6/J mice, in which NAFLD was induced by carbon tetrachloride (CCl4) treatment after high-fat diet (HFD) feeding, and choline-deficient, L-amino-acid-defined HFD (CDAHFD) feeding. Repeated dose administration of coagonist significantly attenuated liver inflammation and steatosis induced by acute and long-term treatment with CCl4 in HFD-fed mice. Coagonist markedly attenuated the CDAHFD-induced expression of TIMP-1, MMP-9, TNF-α, MCP-1, COL1A1, and α-SMA. It also inhibited progression of hepatic steatosis and fibrosis in mice. Exendin-4 was better than glucagon, but coagonist was most effective in reduction of hepatic inflammation as well as steatosis. Coagonist of GLP-1R and GCGR improved NAFLD in C57BL6/J mice. This effect is mediated by reduction in lipotoxicity and inflammation in liver.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/agonistas , Glucagon/farmacologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Peptídeos/farmacologia , Receptores de Glucagon/agonistas , Peçonhas/farmacologia , Animais , Exenatida , Glucagon/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Peptídeos/uso terapêutico , Peçonhas/uso terapêutico
7.
Chem Biol Interact ; 282: 13-21, 2018 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-29325849

RESUMO

Dyslipidemia enhances progression of atherosclerosis. Coagonist of GLP-1 and glucagon are under clinical investigation for the treatment of obesity and diabetes. Earlier, we have observed that coagonist reduced circulating and hepatic lipids, independent of its anorexic effects. Here, we investigated the role of coagonist of GLP-1 and glucagon receptors in complications of diet-induced dyslipidemia in hamsters and humanized double transgenic mice. Hamsters fed on high fat high cholesterol diet were treated for 8 weeks with coagonist of GLP-1 and glucagon receptors (75 and 150 µg/kg). Pair-fed control was maintained. Cholesterol fed transgenic mice overexpressing hApoB100 and hCETP with coagonist (300 µg/kg) for 4 weeks. After the completion of treatment, biochemical estimations were done. Coagonist treatment reduced triglycerides in plasma, liver and aorta, plasma cholesterol and hepatic triglyceride secretion rate. Expressions of HMG-CoA reductase and SBREBP-1C were reduced and expressions of LDLR, CYP7A1, ABCA1 and ABCB11 were increased in liver, due to coagonist treatment. Coagonist treatment increased bile flow rate and biliary cholesterol excretion. IL-6 and TNF-α were reduced in plasma and expression of TNF-α, MCP-1, MMP-9 and TIMP-1 decreased in liver. Treatment with coagonist reduced oxidative stress in liver and aorta. Energy expenditure was increased and respiratory quotient was reduced by coagonist treatment. These changes were correlated with reduced hepatic inflammation and lipids in liver and aorta in coagonist treated hamsters. Coagonist treatment also reduced lipids in cholesterol-fed transgenic mice. These changes were independent of glycaemia and anorexia observed after coagonist treatment. Long term treatment with coagonist of GLP-1 and glucagon receptor ameliorated diet-induced dyslipidemia and atherosclerosis by regulating bile homeostasis, liver inflammation and energy expenditure.


Assuntos
Aterosclerose/metabolismo , Dislipidemias/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glucagon/metabolismo , Inflamação/metabolismo , Fígado/metabolismo , Animais , Aterosclerose/patologia , Colesterol/metabolismo , Cricetinae , Dislipidemias/patologia , Inflamação/patologia , Metabolismo dos Lipídeos/fisiologia , Fígado/patologia , Masculino , Camundongos , Camundongos Transgênicos , Receptores de Glucagon/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-29357809

RESUMO

BACKGROUND: Obesity, diabetes and dyslipidemica are the key pathogenic stimulus that enhances progression of Non-Alcoholic Fatty Liver Disease (NAFLD). Coagonist of Glucagon Like- Peptide-1 (GLP-1) Receptor (GLP-1R) and Glucagon Receptor (GCGR) are being evaluated for obesity and diabetes. GLP-1 analogs have shown to reverse diabetes and obesity. Glucagon treatment reduces lipids after acute and chronic treatment. OBJECTIVE: In this study, we have investigated the effect of co-agonist on the prevention of NAFLD induced by long-term feeding of High Fat Diet (HFD). METHOD: We have used HFD to induce NAFLD after chronic feeding in mice. Co-agonist treatment (150 µg.kg-1, s.c.) was initiated with induction of HFD, which was continued for 40 weeks. Body weight, food intake, glucose homeostasis, lipid profile, inflammatory and fibrotic markers were assessed at the end of treatment. RESULTS: Co-agonist treatment prevented body weight gain, glucose intolerance and insulin resistance. Treatment with co-agonist reduced NEFA, increased FGF21 and adiponectin levels. Co-agonist increased glycerol release and energy expenditure, while decreased respiratory quotient. Co-agonist reduced lipids in circulation and liver. Expression of SREBP-1C, SCD-1, ACC and FAS were decreased, while ACOX1 and CPT1 were increased after co-agonist treatment. Inflammatory cytokine TNF-α and IL-6 in plasma and expression of MCP-1, TGF-ß, MMP-9, TNF-α, TIMP-1, α-SMA, and COL1A1 were decreased after co-agonist treatment. Plasma transaminases, hepatic TBARS, hepatic hydroxyproline and relative liver weight were suppressed after co-agonist treatment. Fat accumulation, inflammation and fibrosis were reduced in histological assessment of liver in co-agonist treated animals. CONCLUSION: Co-agonist prevented development of HFD-induced NAFLD by ameliorating obesity, diabetes, inflammation and fibrosis.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/agonistas , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Receptores de Glucagon/agonistas , Animais , Dieta Hiperlipídica , Humanos , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real
9.
Liver Int ; 38(6): 1084-1094, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29164820

RESUMO

BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are common clinico-pathological conditions that affect millions of patients worldwide. In this study, the efficacy of saroglitazar, a novel PPARα/γ agonist, was assessed in models of NAFLD/NASH. METHODS & RESULTS: HepG2 cells treated with palmitic acid (PA;0.75 mM) showed decreased expression of various antioxidant biomarkers (SOD1, SOD2, glutathione peroxidase and catalase) and increased expression of inflammatory markers (TNFα, IL1ß and IL6). These effects were blocked by saroglitazar, pioglitazone and fenofibrate (all tested at 10µM concentration). Furthermore, these agents reversed PA-mediated changes in mitochondrial dysfunction, ATP production, NFkB phosphorylation and stellate cell activation in HepG2 and HepG2-LX2 Coculture studies. In mice with choline-deficient high-fat diet-induced NASH, saroglitazar reduced hepatic steatosis, inflammation, ballooning and prevented development of fibrosis. It also reduced serum alanine aminotransferase, aspartate aminotransferase and expression of inflammatory and fibrosis biomarkers. In this model, the reduction in the overall NAFLD activity score by saroglitazar (3 mg/kg) was significantly more prominent than pioglitazone (25 mg/kg) and fenofibrate (100 mg/kg). Pioglitazone and fenofibrate did not show any improvement in steatosis, but partially improved inflammation and liver function. Antifibrotic effect of saroglitazar (4 mg/kg) was also observed in carbon tetrachloride-induced fibrosis model. CONCLUSIONS: Saroglitazar, a dual PPARα/γ agonist with predominant PPARα activity, shows an overall improvement in NASH. The effects of saroglitazar appear better than pure PPARα agonist, fenofibrate and PPARγ agonist pioglitazone.


Assuntos
Biomarcadores/sangue , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , PPAR alfa/agonistas , Fenilpropionatos/farmacologia , Pirróis/farmacologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Dieta Hiperlipídica , Fenofibrato/farmacocinética , Células Hep G2 , Humanos , Células de Kupffer/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/patologia , Pioglitazona/farmacologia , Fator de Necrose Tumoral alfa/sangue
10.
Food Res Int ; 99(Pt 3): 1021-1027, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28865612

RESUMO

This study investigates traditional and non-conventional methods of extraction of protein from Irish brown seaweed A. nodosum. Acid, alkali, combined acid-alkali with and without ultrasound pretreatment were investigated for extraction of protein from A. nodosum. Molecular weight of protein was determined using high performance size exclusion chromatography and amino acid profiling was carried out using an amino acid analyzer. Combination of first acid and then alkali extraction was found to be the most efficient method of extraction among all methods investigated (59% of recovery); followed by single step of alkali extraction assisted with ultrasound (68.4µm) which was able to extract 57% of total protein. Alkaline extraction was shown to yield the best protein/algae liquefaction ratio (1.28). This can be attributed to the release of polysaccharide complexes first by acid and then solubilization of proteins by alkali solvent. The molecular weight of extracted protein was found to be relatively low, in the range of 2-4kDa average MW. The alkali method of extraction was found to be optimum for extraction of amino acids from A. nodosum.


Assuntos
Ascophyllum/química , Proteínas de Plantas/isolamento & purificação , Plantas Comestíveis/química , Alga Marinha/química , Sequência de Aminoácidos , Cromatografia em Gel , Manipulação de Alimentos/métodos , Peso Molecular , Valor Nutritivo , Proteólise , Análise de Sequência de Proteína , Ultrassom
11.
Ultrason Sonochem ; 31: 310-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26964954

RESUMO

The effect of ultrasound pretreatment prior to convective drying on drying kinetics and selected quality properties of mulberry leaves was investigated in this study. Ultrasound pretreatment was carried out at 25.2-117.6 W/L for 5-15 min in a continuous mode. After sonication, mulberry leaves were dried in a hot-air convective dryer at 60 °C. The results revealed that ultrasound pretreatment not only affected the weight of mulberry leaves, it also enhanced the convective drying kinetics and reduced total energy consumption. The drying kinetics was modeled using a diffusion model considering external resistance and effective diffusion coefficient De and mass transfer coefficient hm were identified. Both De and hm during convective drying increased with the increase of acoustic energy density (AED) and ultrasound duration. However, De and hm increased slowly at high AED levels. Furthermore, ultrasound pretreatment had a more profound influence on internal mass transfer resistance than on external mass transfer resistance during drying according to Sherwood numbers. Regarding the quality properties, the color, antioxidant activity and contents of several bioactive compounds of dried mulberry leaves pretreated by ultrasound at 63.0 W/L for 10 min were similar to that of mulberry leaves without any pretreatments. Overall, ultrasound pretreatment is effective to shorten the subsequent drying time of mulberry leaves without damaging the quality of final product.


Assuntos
Morus/química , Folhas de Planta/química , Ultrassom , Cinética
12.
Exp Toxicol Pathol ; 68(1): 1-13, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26414849

RESUMO

A retrospective analysis was undertaken at Zydus Research Centre to understand the incidences of spontaneous lesions in endocrine glands of Wistar rats and beagle dogs. The data from a total of 841 Wistar rats (418 males and 423 females) and 144 beagle dogs (72 males and 72 females) was used from placebo/vehicle treated control group of different non-clinical toxicity studies. The lesions in various endocrine glands were classified according to the species and age of the animals at termination of study. Among the endocrine glands, the highest numbers (types) of spontaneous lesions were observed in adrenal glands followed in descending order by pituitary, thyroid, endocrine pancreas and parathyroid glands in Wistar rats. In beagle dogs, highest numbers (types) of spontaneous lesions were seen in adrenals followed by thyroid, endocrine pancreas, pituitary and parathyroid gland. In adrenal glands of Wistar rats, the incidences of cortical cell vacuolation, hemorrhages and hemangiectasis/peliosis were increased with age. Incidence of peliosis at ∼110 weeks of age was higher in female rats. Among the proliferative lesions in rats, higher incidences of cortical cell hyperplasia was observed followed by medullary hyperplasia, complex pheochromocytoma, cortical cell adenoma and cortical adenocarcinoma. In beagle dogs, the incidences of hemangiectasis and cortical cell vacuolation in adrenal glands were higher in 18-21 months aged dogs in both the sexes as compared to 10-12 months of age. In pituitary gland, the incidences of cystic changes were higher in older rats and dogs and the incidences were more in beagles as compared to rats. In thyroid glands, C-cell (parafollicular cells) hyperplasia/complex was observed more frequently in both the species. Few incidences of cystic changes were observed in parathyroid of 18-21 months aged beagle dogs. In endocrine pancreas, few incidences of islet-cell vacuolation, atrophy and hyperplasia were observed in both the species. The Islet cell hyperplasia was found to be more frequent in male rats at ∼110 weeks of age.


Assuntos
Doenças do Sistema Endócrino/veterinária , Envelhecimento , Animais , Cães , Doenças do Sistema Endócrino/epidemiologia , Feminino , Masculino , Ratos , Ratos Wistar
13.
Mar Drugs ; 13(7): 4270-80, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26184235

RESUMO

Ultrasound assisted extraction (UAE), purification, characterization and antioxidant activity of laminarin from Irish brown seaweeds Ascophyllum nodosum and Laminarina hyperborea were investigated. UAE was carried out using 60% ultrasonic power amplitude and 0.1 M hydrochloric acid for 15 min. Separately, solid-liquid extraction was carried in an orbital shaker using 0.1 M hydrochloric acid at 70 °C for 2.5 h. UAE with hydrochloric acid resulted in the highest concentration of laminarin, 5.82% and 6.24% on dry weight basis from A. nodosum and L. hyperborea, respectively. Purification of all extracts was carried out using molecular weight cut off dialysis at 10 kDa. Characterization of the laminarin fraction was carried out using matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Antioxidant activity of A. nodosum and L. hyperborea extracts had 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition levels of 93.23% and 87.57%, respectively. Moreover, these extracts have shown inihibition of bacterial growth of Staphylcoccus aureus, Listeria monocytogenes, Escherichia coli and Salmonella typhimurium.


Assuntos
Ascophyllum/química , Glucanos/isolamento & purificação , Laminaria/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Escherichia coli/efeitos dos fármacos , Glucanos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Ultrassom/métodos
14.
Ultrason Sonochem ; 23: 302-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25454823

RESUMO

The effect of ultrasound pre-treatment on the drying kinetics of brown seaweed Ascophyllum nodosum under hot-air convective drying was investigated. Pretreatments were carried out at ultrasound intensity levels ranging from 7.00 to 75.78 Wcm(-2) for 10 min using an ultrasonic probe system. It was observed that ultrasound pre-treatments reduced the drying time required. The shortest drying times were obtained from samples pre-treated at 75.78 Wcm(-2). The fit quality of 6 thin-layer drying models was also evaluated using the determination of coefficient (R(2)), root means square error (RMSE), AIC (Akaike information criterion) and BIC (Bayesian information criterion). Drying kinetics were modelled using the Newton, Henderson and Pabis, Page, Wang and Singh, Midilli et al. and Weibull models. The Newton, Wang and Singh, and Midilli et al. models showed the best fit to the experimental drying data. Color of ultrasound pretreated dried seaweed samples were lighter compared to control samples. It was concluded that ultrasound pretreatment can be effectively used to reduce the energy cost and drying time for drying of A. nodosum.


Assuntos
Ascophyllum/química , Dessecação/métodos , Alga Marinha/química , Ultrassom , Ar , Convecção , Temperatura Alta , Cinética , Modelos Teóricos , Pigmentação
15.
Ultrason Sonochem ; 23: 308-16, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25453215

RESUMO

The objective of this study was to investigate the effect of key extraction parameters of extraction time (5-25 min), acid concentration (0-0.06 M HCl) and ultrasound amplitude (22.8-114 µm) on yields of bioactive compounds (total phenolics, fucose and uronic acid) from Ascophyllumnodosum. Response surface methodology was employed to optimize the extraction variables for bioactive compounds' yield. A second order polynomial model was fitted well to the extraction experimental data with (R(2)>0.79). Extraction yields of 143.12 mgGAE/gdb, 87.06 mg/gdb and 128.54 mg/gdb were obtained for total phenolics, fucose and uronic acid respectively at optimized extraction conditions of extraction time (25 min), acid concentration (0.03 M HCl) and ultrasonic amplitude (114 µm). Mass spectroscopy analysis of extracts show that ultrasound enhances the extraction of high molecular weight phenolic compounds from A. nodosum. This study demonstrates that ultrasound assisted extraction (UAE) can be employed to enhance extraction of bioactive compounds from seaweed.


Assuntos
Ascophyllum/química , Fracionamento Químico/métodos , Fucose/isolamento & purificação , Fenóis/isolamento & purificação , Alga Marinha/química , Ultrassom/métodos , Ácidos Urônicos/isolamento & purificação , Ácido Clorídrico/química , Modelos Teóricos , Estatística como Assunto , Taninos/análise , Taninos/isolamento & purificação , Fatores de Tempo
16.
Cytokine ; 66(1): 30-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24548422

RESUMO

TNF-α converting enzyme (TACE) processes the membrane TNF-α to release the bioactive soluble TNF-α. Several evidences suggest the involvement of TNF-α and TACE in inflammatory bowel disease (IBD). Tissue inhibitor of metalloproteinase (TIMP)-3, an endogenous inhibitor of TACE, is positively associated with silent information regulator (SIRT)-1. We aimed to study the expression of TACE, TIMP-3 and SIRT-1 at different stages of colitis and how TACE is regulated in response to SIRT-1 activation. Acute colitis was induced by 3.5% dextran sulfate sodium (DSS) in drinking water for 5days and levels of cytokines and mRNA expression of TACE, TIMP-3 and SIRT-1 were measured in colon at different time intervals. Next, the effect of SIRT-1 activator (resveratrol) or a selective TACE inhibitor (compound 11p) treatment was evaluated. Elevated levels of TNF-α, interleukin (IL)-6, IL-1ß, interferon (IFN)-γ and IL-17 were observed during DSS exposure phase which restored to the normal level after DSS removal. A significant increase in TACE and suppression in TIMP-3 and SIRT-1 mRNA level was observed during DSS exposure phase which reverts back to normal towards the remission phase. Treatment with resveratrol significantly elevated SIRT-1 and TIMP-3 and suppressed TACE mRNA expression and was associated with amelioration of disease. Furthermore, treatment with selective TACE inhibitor significantly suppressed body weight loss, disease activity index, colonic myeloperoxidase activity and the elevated levels of cytokines after DSS challenge. These results strongly emphasize the involvement of TACE in colon inflammation and inhibition of TACE directly or indirectly via SIRT-1 activation ameliorates colitis.


Assuntos
Proteínas ADAM/metabolismo , Colo/enzimologia , Colo/patologia , Inflamação/enzimologia , Sirtuína 1/metabolismo , Proteínas ADAM/antagonistas & inibidores , Proteína ADAM17 , Doença Aguda , Animais , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Citocinas/metabolismo , Sulfato de Dextrana , Feminino , Inflamação/tratamento farmacológico , Inflamação/patologia , Cinética , Camundongos , Camundongos Endogâmicos C57BL , Resveratrol , Estilbenos/farmacologia , Estilbenos/uso terapêutico , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-3/metabolismo
17.
Int Immunopharmacol ; 17(2): 229-36, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23816535

RESUMO

Emerging evidence suggest that tumor necrosis factor (TNF)-α plays a major role in pathogenesis of auto-immune hepatitis (AIH) induced liver injury. Blockade of TNF-α synthesis or bio-activity protects against experimental AIH. TNF-α converting enzyme (TACE) is a member of the ADAM (a disintegrin and metalloproteinase) family which processes precursor TNF-α to release soluble TNF-α. We hypothesized that selective inhibition of TACE might protect AIH. To investigate this, we studied the effects of a selective TACE inhibitor DPC-333 on murine model of liver injury and fibrosis induced with concanavalin A (Con A). Pre-treatment with DPC-333 significantly suppressed plasma alanine transaminase, aspartate transaminase and cytokines such as TNF-α, interferon (IFN)-γ, interleukin (IL)-2 and IL-6 levels due to acute Con A challenge. Interestingly; DPC-333 inhibited liver poly (ADP-ribose) polymerase (PARP)-1 activity which was associated with reduced number of necrotic hepatocytes in histological examination and mortality associated with Con A. In fibrosis study, repeated Con A administration significantly up-regulated liver collagen deposition as assessed by measurement of hydroxyproline content which was further confirmed in liver histology with Masson's trichrome staining. Treatment with 30mg/kg of DPC-333 was able to suppress liver hydroxyproline and fibrous tissue proliferation which corroborated well with inhibition in expression of pro-fibrotic genes such as tissue inhibitor of metalloproteinase (TIMP)-1 and transforming growth factor (TGF)-ß1. These observations suggest that selective TACE inhibition is an effective approach for the treatment of both immune mediated hepatic inflammation and fibrosis.


Assuntos
Proteínas ADAM/antagonistas & inibidores , Hepatite Autoimune/tratamento farmacológico , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Quinolinas/administração & dosagem , Proteína ADAM17 , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Células Cultivadas , Concanavalina A/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Fibrose , Hepatite Autoimune/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Quinolinas/farmacologia , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Ativação Transcricional/efeitos dos fármacos
18.
J Agric Food Chem ; 61(20): 4667-75, 2013 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-23634989

RESUMO

Marine algae are a rich source of bioactive compounds. This paper outlines the main bioactive compounds in marine algae and recent advances in novel technologies for extracting them. Novel extraction technologies reviewed include enzyme-assisted extraction, microwave-assisted extraction, ultrasound-assisted extraction, supercritical fluid extraction, and pressurized liquid extraction. These technologies are reviewed with respect to principles, benefits, and potential applications for marine algal bioactives. Advantages of novel technologies include higher yield, reduced treatment time, and lower cost compared to traditional solvent extraction techniques. Moreover, different combinations of novel techniques used for extraction and technologies suitable for thermolabile compounds are identified. The limitations of and challenges to employing these novel extraction technologies in industry are also highlighted.


Assuntos
Clorófitas/química , Suplementos Nutricionais , Rodófitas/química , Carotenoides/isolamento & purificação , Enzimas , Ácidos Graxos Ômega-3/isolamento & purificação , Micro-Ondas , Fenóis/isolamento & purificação , Polissacarídeos/isolamento & purificação , Ultrassom
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