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1.
Biomolecules ; 11(8)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34439847

RESUMO

Food waste is a global problem due to its environmental and economic impact, so there is great demand for the exploitation of new functional applications. The winemaking process leads to an incomplete extraction of high-value compounds, leaving the pomace still rich in polyphenols. This study was aimed at optimising and validating sustainable routes toward the extraction and further valorisation of these polyphenols, particularly for cosmeceutical applications. New formulations based on red grape pomace polyphenols and natural deep eutectic solvents (NaDESs) were here investigated, namely betaine combined with citric acid (BET-CA), urea (BET-U) and ethylene glycol (BET-EG), in which DESs were used both as extracting and carrying agents for polyphenols. The flavonoid profile determined by HPLC-MS/MS analysis showed similar malvidin content (51-56 µg mL-1) in the DES combinations, while BET-CA gave the best permeation performance in Franz cells, so it was further investigated in 3D human keratinocytes (HaCat spheroids) injured with the pro-oxidant agent menadione. BET-CA treatment showed good intracellular antioxidant activity (IC50 0.15 ± 0.02 µg mL-1 in malvidin content) and significantly decreased (p < 0.001) the release of the pro-inflammatory cytokine IL-8, improving cell viability. Thus, BET-CA formulation is worthy of investigation for potential use as a cosmetic ingredient to reduce oxidative stress and inflammation, which are causes of skin aging.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Eliminação de Resíduos/métodos , Vitis/metabolismo , Cosméticos/química , Células HaCaT , Humanos , Estresse Oxidativo/efeitos dos fármacos
2.
Anal Chim Acta ; 1163: 338515, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34024424

RESUMO

Exposure to mycotoxins, which may contaminate food and feed commodities, represents a serious health risk for consumers. Ochratoxin A (OTA) is one of the most abundant and toxic mycotoxins, thus specific regulations for fixing its maximum admissible levels in foodstuff have been established. Lateral Flow ImmunoAssay (LFIA)-based devices have been proposed as screening tools to avoid OTA contamination along the whole food chain. We report a portable, user-friendly smartphone-based biosensor for the detection and quantification of OTA in wine and instant coffee, which combines the LFIA approach with chemiluminescence (CL) detection. The device employs the smartphone camera as a light detector and uses low-cost, disposable analytical cartridges containing the LFIA strip and all the necessary reagents. The analysis can be carried out at the point of need by non-specialized operators through simple manual operations. The biosensor allows OTA quantitative detection in wine and coffee samples up to 25 µg L-1 and with limits of detection of 0.3 and 0.1 µg L-1, respectively, which are below the European law-fixed limits. These results demonstrate that the developed device can be used for routine monitoring of OTA contamination, enabling rapid and reliable identification of positive samples requiring confirmatory analysis.


Assuntos
Técnicas Biossensoriais , Ocratoxinas , Vinho , Café , Contaminação de Alimentos/análise , Luminescência , Ocratoxinas/análise , Smartphone , Vinho/análise
3.
Anal Chem ; 93(20): 7388-7393, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33973781

RESUMO

The availability of portable analytical devices for on-site monitoring and rapid detection of analytes of forensic, environmental, and clinical interest is vital. We report the development of a portable device for the detection of biochemiluminescence relying on silicon photomultiplier (SiPM) technology, called LuminoSiPM, which includes a 3D printed sample holder that can be adapted for both liquid samples and paper-based biosensing. We performed a comparison of analytical performance in terms of detectability with a benchtop luminometer, a portable cooled charge-coupled device (CCD sensor), and smartphone-integrated complementary metal oxide semiconductor (CMOS) sensors. As model systems, we used two luciferase/luciferin systems emitting at different wavelengths using purified protein solutions: the green-emitting P. pyralis mutant Ppy-GR-TS (λmax 550 nm) and the blue-emitting NanoLuc (λmax 460 nm). A limit of detection of 9 femtomoles was obtained for NanoLuc luciferase, about 2 and 3 orders of magnitude lower than that obtained with the portable CCD camera and with the smartphone, respectively. A proof-of-principle forensic application of LuminoSiPM is provided, exploiting an origami chemiluminescent paper-based sensor for acetylcholinesterase inhibitors, showing high potential for this portable low-cost device for on-site applications with adequate sensitivity for detecting low light intensities in critical fields.


Assuntos
Técnicas Biossensoriais , Luminescência , Luz , Luciferases , Smartphone
4.
Nutrients ; 12(10)2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33036498

RESUMO

Lactic acid bacteria (LAB) "fermentates" confer a beneficial effect on intestinal function. However, the ability of new fermentations to improve LAB broth activity in preventing pathogen-induced intestinal inflammation and barrier dysfunction has not yet been studied. The objective of this study was to determine if broths of LAB fermented with Eruca sativa or Barbarea verna seed extracts prevent gut barrier dysfunction and interleukin-8 (CXCL8) release in vitro in human intestinal Caco-2 cells infected with enterohemorrhagic Escherichia coli (EHEC) O157:H7. LAB broths were assayed for their effects on EHEC growth and on Caco-2 viability; thereafter, their biological properties were analysed in a co-culture system consisting of EHEC and Caco-2 cells. Caco-2 cells infected with EHEC significantly increased CXCL8 release, and decreased Trans-Epithelial Electrical Resistance (TEER), a barrier-integrity marker. Notably, when Caco-2 cells were treated with LAB broth enriched with E. sativa seed extract and thereafter infected, both CXCL8 expression and epithelial dysfunction reduced compared to in untreated cells. These results underline the beneficial effect of broths from LAB fermented with E. sativa seed extracts in gut barrier and inflammation after EHEC infection and reveal that these LAB broths can be used as functional bioactive compounds to regulate intestinal function.


Assuntos
Brassicaceae/química , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/crescimento & desenvolvimento , Fermentação , Gastroenterite/prevenção & controle , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Lactobacillus acidophilus , Extratos Vegetais/farmacologia , Probióticos/farmacologia , Sementes/química , Antibacterianos , Barbarea/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Farmacorresistência Bacteriana , Impedância Elétrica , Infecções por Escherichia coli , Escherichia coli O157/patogenicidade , Gastroenterite/microbiologia , Humanos , Interleucina-8/metabolismo , Mucosa Intestinal/fisiologia , Fitoterapia , Extratos Vegetais/isolamento & purificação
5.
Microorganisms ; 8(7)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630107

RESUMO

The rice-starch processing industry produces large amounts of a protein-rich byproducts during the conversion of broken rice to powder and crystal starch. Given the poor protein solubility, this material is currently discarded or used as animal feed. To fully exploit rice's nutritional properties and reduce this waste, a biotechnological approach was adopted, inducing fermentation with selected microorganisms capable of converting the substrate into peptide fractions with health-related bioactivity. Lactic acid bacteria were preferred to other microorganisms for their safety, efficient proteolytic system, and adaptability to different environments. Peptide fractions with different molecular weight ranges were recovered from the fermented substrate by means of cross-flow membrane filtration. The fractions displayed in vitro antioxidant, antihypertensive, and anti-tyrosinase activities as well as cell-based anti-inflammatory and anti-aging effects. In the future, the peptide fractions isolated from this rice byproduct could be directly exploited as health-promoting functional foods, dietary supplements, and pharmaceutical preparations. The suggested biotechnological process harnessing microbial bioconversion may represent a potential solution for many different protein-containing substrates currently treated as byproducts (or worse, waste) by the food industry.

6.
Anal Bioanal Chem ; 411(19): 4937-4949, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30972468

RESUMO

Cell-based assays utilizing reporter gene technology have been widely exploited for biosensing, as they provide useful information about the bioavailability and cell toxicity of target analytes. The long assay time due to gene transcription and translation is one of the main drawbacks of cell biosensors. We report the development of two yeast biosensors stably expressing human estrogen receptors α and ß and employing NanoLuc as the reporter protein to upgrade the widely used yeast estrogen screening (YES) assays. A viability control strain was also developed based on a chimeric green-emitting luciferase, PLG2, expressed for the first time in Saccharomycescerevisiae. Thanks to their brightness, NanoLuc and PLG2 provided excellent sensitivity, enabling the implementation of these biosensors into low-cost smartphone-based devices. The developed biosensors had a rapid (1 h) response and reported on (anti)estrogenic activity via human estrogen receptors α and ß as well as general sample toxicity. Under optimized conditions, we obtained LODs of 7.1 ± 0.4 nM and 0.38 ± 0.08 nM for E2 with nanoYESα and nanoYESß, respectively. As a proof of concept, we analyzed real samples from plants showing significant estrogenic activity or known to contain significant amounts of phytoestrogens. Graphical abstract.


Assuntos
Técnicas Biossensoriais , Disruptores Endócrinos/análise , Medições Luminescentes/métodos , Nanotecnologia , Saccharomyces cerevisiae/metabolismo , Smartphone , Genes Reporter , Limite de Detecção , Luciferases/genética , Medicago sativa/química , Extratos Vegetais/química , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/genética , Glycine max/química , Poluentes Químicos da Água/análise
7.
Mol Nutr Food Res ; 61(11)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28755406

RESUMO

SCOPE: We aimed examining apple polyphenols' effect on uricemia and endothelial function in a sample of overweight subjects. METHODS AND RESULTS: This was a two-phased study. In vitro experiment aimed to evaluate apple polyphenols' ability to lower uric acid in comparison with allopurinol. In vivo study consisted in a randomized, double-blind, parallel placebo-controlled clinical trial involving 62 overweight volunteers with suboptimal values of fasting plasma glucose (100 mg/dL≤FPG≤125 mg/dL), randomized to 300 mg apple polyphenols or placebo for 8 weeks. Apple polyphenols extract inhibited xanthine oxidase activity, with an IC50 = 130 ± 30 ng/mL; reducing uric acid production with an IC50 = 154 ± 28 ng/mL. During the trial, after the first 4 weeks of treatment, FPG decreased in the active treated group (-6.1%, p < 0.05), while no significant changes were observed regarding the other hematochemistry parameters. After 4 more weeks of treatment, active-treated patients had an improvement in FPG compared to baseline (-10.3%, p < 0,001) and the placebo group (p < 0,001). Uric acid (-14.0%, p < 0.05 versus baseline; p < 0.05 versus placebo) and endothelial reactivity (0.24±0.09, p = 0.009 versus baseline; p < 0.05 versus placebo) significantly improved too. CONCLUSION: In vivo, apple polyphenols extract has a positive effect on vascular oxidative stress and endothelium function and reduce FPG and uric acid by inhibiting xanthine oxidase, as our In vitro experiment attests.


Assuntos
Antioxidantes/uso terapêutico , Suplementos Nutricionais , Malus/química , Sobrepeso/dietoterapia , Estresse Oxidativo , Extratos Vegetais/uso terapêutico , Doenças Vasculares/prevenção & controle , Antioxidantes/metabolismo , Glicemia/análise , Índice de Massa Corporal , Células Cultivadas , Método Duplo-Cego , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/uso terapêutico , Feminino , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Hiperuricemia/etiologia , Hiperuricemia/prevenção & controle , Masculino , Sobrepeso/metabolismo , Sobrepeso/patologia , Sobrepeso/fisiopatologia , Extratos Vegetais/metabolismo , Polifenóis/uso terapêutico , Estado Pré-Diabético/etiologia , Estado Pré-Diabético/prevenção & controle , Ácido Úrico/sangue , Doenças Vasculares/etiologia , Resistência Vascular , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismo
8.
N Biotechnol ; 39(Pt A): 51-58, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28698131

RESUMO

The present work aimed at optimizing a two-step enzymatic plus solvent-based process for the recovery of bioactive compounds from white grape (Vitis vinifera L., mix of Trebbiano and Verdicchio cultivars) pomace, the winemaking primary by-product. Phenolic compounds solubilised by water enzyme-assisted and ethanol-based extractions of wet (WP) and dried (DP) pomace were characterised for composition and tested for antioxidant, anti-tyrosinase and anti-inflammatory bioactivities. Ethanol treatment led to higher phenol yields than water extraction, while DP samples showed the highest capacity of releasing polyphenols, most probably as a positive consequence of the pomace drying process. Different compositions and bioactivities were observed between water and ethanol extracts and among different treatments and for the first time the anti-tyrosinase activity of V. vinifera pomace extracts, was here reported. Enzymatic treatments did not significantly improve the total amount of solubilised compounds; Celluclast in DP led to the recovery of extracts enriched in specific compounds, when compared to control. The best extracts (enzymatic plus ethanol treatment total levels) were obtained from DP showing significantly higher amounts of polyphenols, flavonoids, flavanols and tannins and exerted higher antioxidant and anti-tyrosinase activities than WP total extracts. Conversely, anti-inflammatory capacity was only detected in water (with and without enzyme) extracts, with WP samples showing on average a higher activity than DP. The present findings demonstrate that white grape pomace constitute a sustainable source for the extraction of phytochemicals that might be exploited as functional ingredients in the food, nutraceutical, pharmaceutical or cosmetic industries.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Etanol/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Vitis/química , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Células HEK293 , Humanos , Monofenol Mono-Oxigenase/metabolismo , Fenóis/análise , Polifenóis/análise , Taninos/análise
9.
J Pharm Biomed Anal ; 144: 236-241, 2017 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-28336003

RESUMO

Indoor air pollutants and odorants may have psychological and physical impact on exposed individuals and the unpleasant room air is considered as one of the factors associated with sick building syndrome comprising general symptoms such as headache and lethargy. Approaches for improving the quality of indoor air are thus important as support for human health and well-being. Photo-oxidation catalyzed by titanium dioxide (TiO2), is one of the methods used for elimination of volatile organic compounds, which are the cause of odor nuisance in indoor and outdoor air. In the present investigation, the efficacy of an experimental anti-odor air freshener based on TiO2 nanoparticles was estimated by testing its ability in removing from a small air chamber (200mL) the odor of triethylamine solutions (50µL at concentrations between 0.700 to 700mM), used as a model volatile molecule for simulating fish-like unpleasant indoor environment. The evaluation was performed by electronic nose which provided a holistic and objective data on the efficacy of the product, demonstrating that the effects of triethylamine even at the highest tested concentrations can be completely removed by application of 3.0g of the product at 25% TiO2 nanoparticles concentration. The obtained results were confirmed by gaschromatography-mass spectrometry (GC-MS) analysis addressed to the quantitative determination of residual triethylamine in the environment after treatment by the anti-odor product.


Assuntos
Nanopartículas Metálicas , Poluentes Atmosféricos , Nariz Eletrônico , Humanos , Espectrometria de Massas , Odorantes , Síndrome do Edifício Doente , Titânio
10.
Anal Bioanal Chem ; 408(30): 8859-8868, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27853830

RESUMO

The availability of smartphones with high-performance digital image sensors and processing power has completely reshaped the landscape of point-of-need analysis. Thanks to the high maturity level of reporter gene technology and the availability of several bioluminescent proteins with improved features, we were able to develop a bioluminescence smartphone-based biosensing platform exploiting the highly sensitive NanoLuc luciferase as reporter. A 3D-printed smartphone-integrated cell biosensor based on genetically engineered Hek293T cells was developed. Quantitative assessment of (anti)-inflammatory activity and toxicity of liquid samples was performed with a simple and rapid add-and-measure procedure. White grape pomace extracts, known to contain several bioactive compounds, were analyzed, confirming the suitability of the smartphone biosensing platform for analysis of untreated complex biological matrices. Such approach could meet the needs of small medium enterprises lacking fully equipped laboratories for first-level safety tests and rapid screening of new bioactive products. Graphical abstract Smartphone-based bioluminescence cell biosensor.


Assuntos
Anti-Inflamatórios/farmacologia , Técnicas Biossensoriais/instrumentação , Luciferases/genética , Medições Luminescentes/instrumentação , Extratos Vegetais/farmacologia , Smartphone/instrumentação , Anti-Inflamatórios/química , Desenho de Equipamento , Genes Reporter , Engenharia Genética , Células HEK293 , Humanos , Limite de Detecção , Luciferases/metabolismo , Extratos Vegetais/química , Reprodutibilidade dos Testes , Vitis/química
11.
Curr Med Chem ; 23(14): 1460-76, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27063256

RESUMO

Berberine is a quaternary ammonium salt from the protoberberine group of isoquinoline alkaloids found in such plants as gender Berberis. Berberine is recognised to improve glucose and lipid metabolism disorders and preliminary clinical evidences suggest the ability of berberine to reduce endothelial inflammation improving vascular health, even in patients already affected by cardiovascular diseases, suggesting a possible interesting role of berberine and its metabolites in clinical practice. However, its physicochemical properties, pharmacokinetic, and metabolism are not fully elucidated and contradictory data have been reported. This review provides a summary regarding the pharmacological and biological features of berberine, with a focus on berberine as well as their pharmacologically active metabolites and the different mechanisms underlying their activities in order to clarify the correct use of berberine supplementation, alone or in association with other nutraceuticals, for the management of metabolic disorders associated to increased cardiovascular disease risk. A particular attention has also been given to the available clinical trials assessing its short- and middle- term use tolerability, safety and efficacy in various conditions, such as dyslipidaemia, impaired fasting glucose, metabolic syndrome and type 2 diabetes.


Assuntos
Berberina/uso terapêutico , Doenças Metabólicas/tratamento farmacológico , Animais , Berberina/metabolismo , Humanos
12.
J Antimicrob Chemother ; 71(5): 1148-58, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26888912

RESUMO

OBJECTIVES: As most available antimalarial drugs are ineffective against the Plasmodium falciparum transmission stages, new drugs against the parasite's gametocytes are urgently needed to combat malaria globally. The unique biology of gametocytes requires assays that need to be specific, to faithfully monitor anti-gametocyte activity, and to be easy to perform, cheap and scalable to high-throughput screening (HTS). METHODS: We developed an HTS cell-based assay with P. falciparum gametocytes specifically expressing a potent luciferase. To confirm HTS hit activity for several parasite genotypes, the luciferase assay and the gametocyte lactate dehydrogenase (LDH) assay, usable on any parasite isolate, were compared by screening antimalarial drugs and determining IC50 values of anti-gametocyte hits from the 'Malaria Box' against early- and late-stage gametocytes. RESULTS: Comparison of the two assays, conducted on the early and on late gametocyte stages, revealed an excellent correlation (R(2) > 0.9) for the IC50 values obtained by the respective readouts. Differences in susceptibility to drugs and compounds between the two parasite developmental stages were consistently measured in both assays. CONCLUSIONS: This work indicates that the luciferase and gametocyte LDH assays are interchangeable and that their specific advantages can be exploited to design an HTS pipeline leading to new transmission-blocking compounds. Results from these assays consistently defined a gametocyte chemical susceptibility profile, relevant to the planning of future drug discovery strategies.


Assuntos
Antimaláricos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Plasmodium falciparum/efeitos dos fármacos , Técnicas Citológicas/métodos , Genes Reporter , Ensaios de Triagem em Larga Escala/métodos , Humanos , Concentração Inibidora 50 , L-Lactato Desidrogenase/análise , Luciferases/análise , Plasmodium falciparum/enzimologia , Coloração e Rotulagem
13.
N Biotechnol ; 33(3): 338-44, 2016 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-26705904

RESUMO

The present work aimed at the recovery and characterization of polyphenolic compounds extracted from red grape pomace (Vitis vinifera L.), a winemaking by-product. Polyphenolic compounds of wet (WP) and dried (DP) red pomace were recovered by enzymatic digestions and ethanol-based extractions. Fungamyl and Celluclast enzymes were found to be the most effective in enhancing polyphenol release from WP. WP samples showed the highest capacity of releasing polyphenols with 2h control 24°C and 2h 1% Celluclast resulting as the best treatments. A significantly lower amount of polyphenols was recovered from DP most probably as a consequence of the pomace drying. The best extracts contained high amounts of total polyphenols, flavonoids, tannins and anthocyanins and exerted antioxidant and cholesterol-lowering activities. The results support the possibility of exploiting the extracts coming from grape processing by-products as ingredients for functional and innovative products in the nutraceutical, pharmaceutical or cosmetic fields.


Assuntos
Antioxidantes/farmacologia , Colesterol/metabolismo , Polifenóis/isolamento & purificação , Vitis/química , Resíduos/análise , Cromatografia Líquida de Alta Pressão , Enzimas/metabolismo , Etanol/química , Flavonoides/análise , Extratos Vegetais/química , Taninos/análise , Água/química
14.
Talanta ; 129: 32-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25127562

RESUMO

Electronic nose and capillary electrophoresis were applied in quality control of green tea samples subjected to long-term storage. Twelve representative green teas were considered, available as an "aged" (tea leaves stored during a long-term period of two years) and/or "not aged" (fresh products) samples. Their infusions were analyzed by an electronic nose, equipped with an array of six metal oxide semiconductor (MOS) sensors to obtain olfactive fingerprints of the volatile compounds in the infusions headspace. Upon training and chemometric analysis of acquired data (linear discriminant analysis), the electronic nose was found to be able in correctly classifying unknown samples as "aged" or "not aged". Concomitantly, the infusion samples were analyzed by Cyclodextrin-modified Micellar Electrokinetic Chromatography (CD-MEKC) for determination of catechins. The analysis of seven most represented catechins and the methylxanthines theobromine and caffeine revealed a general loss of the polyphenols in each of the considered aged samples (up to 45%, w/w). In addition, the applied enantioselective method based on (2-hydroxypropyl)-ß-cyclodextrin (HP-ßCD) as chiral selector, was exploited for the estimation of (+)-Gallocatechin in the presence of (-)-Gallocatechin; the latter, as the non-native enantiomer, can be associated to the epimerisation of (-)-Epigallocatechin and was assumed as a marker occurring in case of uncorrected storage conditions of tea leaves. Interestingly, it was observed that epimerization did not significantly occur during aging. The application of CD-MEKC and electronic nose allowed for a fast characterization of green teas taking into account that the aroma is a decisive parameter for the acceptance of the product, whereas the catechins content is associated to the biological value.


Assuntos
Nariz Eletrônico , Eletroforese Capilar/métodos , Análise de Alimentos/métodos , Chá , Cafeína/química , Calibragem , Catequina/análogos & derivados , Catequina/química , Cromatografia/métodos , Cromatografia Capilar Eletrocinética Micelar/métodos , Ciclodextrinas/química , Metais/química , Odorantes , Óxidos/química , Folhas de Planta/química , Polifenóis/química , Controle de Qualidade , Semicondutores , Estereoisomerismo , Teobromina/química , Fatores de Tempo , Xantinas/química
15.
Diabetes ; 61(2): 321-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22210318

RESUMO

As patients decline from health to type 2 diabetes, glucose-stimulated insulin secretion (GSIS) typically becomes impaired. Although GSIS is driven predominantly by direct sensing of a rise in blood glucose by pancreatic ß-cells, there is growing evidence that hypothalamic neurons control other aspects of peripheral glucose metabolism. Here we investigated the role of the brain in the modulation of GSIS. To examine the effects of increasing or decreasing hypothalamic glucose sensing on glucose tolerance and insulin secretion, glucose or inhibitors of glucokinase, respectively, were infused into the third ventricle during intravenous glucose tolerance tests (IVGTTs). Glucose-infused rats displayed improved glucose handling, particularly within the first few minutes of the IVGTT, with a significantly lower area under the excursion curve within the first 10 min (AUC0-10). This was explained by increased insulin secretion. In contrast, infusion of the glucokinase inhibitors glucosamine or mannoheptulose worsened glucose tolerance and decreased GSIS in the first few minutes of IVGTT. Our data suggest a role for brain glucose sensors in the regulation of GSIS, particularly during the early phase. We propose that pharmacological agents targeting hypothalamic glucose-sensing pathways may represent novel therapeutic strategies for enhancing early phase insulin secretion in type 2 diabetes.


Assuntos
Glucose/metabolismo , Hipotálamo/fisiologia , Insulina/metabolismo , Pâncreas/metabolismo , Animais , Glucoquinase/fisiologia , Glucose/farmacologia , Teste de Tolerância a Glucose , Hipotálamo/efeitos dos fármacos , Injeções Intraventriculares , Secreção de Insulina , Masculino , Manoeptulose/farmacologia , Ratos , Ratos Sprague-Dawley
17.
World J Gastroenterol ; 13(10): 1575-8, 2007 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-17461451

RESUMO

AIM: To investigate the effect of a new oral preparation, highly concentrated in fish cartilage, in a group of inflammatory bowel diseases (IBD) patients with chronic iron deficient anemia. METHODS: In an open label pilot study, we supple-mented a group of 25 patients (11 with Crohn's disease and 14 with ulcerative colitis) in stable clinical conditions and chronic anemia with a food supplement which does not contain iron but contains a standardized fraction of fish cartilage glycosaminoglycans and a mixture of antioxidants (Captafer Medestea, Turin, Italy). Patients received 500 mg, twice a day during meals, for at least 4 mo. Patients were suggested to maintain their alimentary habit. At time 0 and after 2 and 4 mo, emocrome, sideremia and ferritin were examined. Paired data were analyzed with Student's t test. RESULTS: Three patients relapsed during the study (2 in the 3rd mo, 1 in the 4th mo), two patients were lost to follow up and two patients dropped out (1 for orticaria, 1 for gastric burning). Of the remaining 18 patients, levels of serum iron started to rapidly increase within the 2nd mo of treatment, P < 0.05), whereas serum ferritin and hemoglobin needed a longer period to significantly improve their serum levels (mo 4) P < 0.05. The product was safe, easy to administer and well tolerated by patients. CONCLUSION: These data suggest a potential new treatment for IBD patients with iron deficiency chronic anemia and warrant further larger controlled studies.


Assuntos
Anemia Ferropriva/dietoterapia , Anemia Ferropriva/etiologia , Cartilagem/química , Doenças Inflamatórias Intestinais/complicações , Polissacarídeos/uso terapêutico , Adulto , Idoso , Anemia Ferropriva/sangue , Animais , Doença Crônica , Suplementos Nutricionais , Feminino , Ferritinas/sangue , Peixes , Hemoglobinas/metabolismo , Humanos , Doenças Inflamatórias Intestinais/sangue , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polissacarídeos/administração & dosagem
18.
Eur J Med Chem ; 40(12): 1331-4, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16129518

RESUMO

The synthesis of a new series of imidazo[2,1-b]thiazole derivatives is described. They were tested as acetylcholinesterase inhibitors by means of a chemiluminescent method suitable for high throughput screening. The compounds without quaternization had no appreciable inhibitory potency probably because they are poorly soluble in water. The corresponding quaternized compounds were good inhibitors with activity related to the spacer employed.


Assuntos
Acetilcolinesterase/efeitos dos fármacos , Imidazóis/síntese química , Imidazóis/farmacologia , Medições Luminescentes/métodos , Tiazóis/síntese química , Tiazóis/farmacologia , Acetilcolinesterase/metabolismo , Avaliação Pré-Clínica de Medicamentos , Imidazóis/química , Estrutura Molecular , Sensibilidade e Especificidade , Relação Estrutura-Atividade , Tiazóis/química
19.
Eur J Med Chem ; 39(9): 785-91, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15337291

RESUMO

The synthesis of N-benzyl-2-chloroindole-3-carboxylic acids related to indomethacin is reported. These compounds were tested on in vitro human neutrophil activation. Some of them, more soluble in water, were tested to define the influence on prostaglandin biosynthesis via inhibition of cyclooxygenases (COX1 and COX2) by a chemiluminescent method suitable for fast screening. Several derivatives showed inhibitory effects and in some cases were more active than the parent compound.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/farmacologia , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/farmacologia , Indóis/química , Neutrófilos/efeitos dos fármacos , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Ativação Enzimática/efeitos dos fármacos , Humanos , Proteínas de Membrana , Estrutura Molecular , Neutrófilos/fisiologia , Prostaglandina-Endoperóxido Sintases/fisiologia , Relação Estrutura-Atividade
20.
Trends Biotechnol ; 22(6): 295-303, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15158059

RESUMO

Recent progress in molecular biology has made available several biotechnological tools that take advantage of the high detectability and rapidity of bioluminescence and chemiluminescence spectroscopy. These developments provide inroads to in vitro and in vivo continuous monitoring of biological processes (e.g. gene expression, protein-protein interaction and disease progression), with clinical, diagnostic and drug discovery applications. Furthermore, combining luminescent enzymes or photoproteins with biospecific recognition elements at the genetic level has led to the development of ultrasensitive and selective bioanalytical tools, such as recombinant whole-cell biosensors, immunoassays and nucleic acid hybridization assays. The high detectability of the luminescence analytical signal makes it appropriate for miniaturized bioanalytical devices (e.g. microarrays, microfluidic devices and high-density-well microtiter plates) for the high-throughput screening of genes and proteins in small sample volumes.


Assuntos
Biotecnologia/métodos , Medições Luminescentes/métodos , Animais , Proteínas de Bactérias/genética , Técnicas Biossensoriais/métodos , Diagnóstico por Imagem/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Fracionamento por Campo e Fluxo/métodos , Humanos , Imunoensaio/métodos , Luminescência , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas de Membrana/genética , Análise em Microsséries/métodos , Nanotecnologia/métodos , Ligação Proteica , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
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