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1.
Carbohydr Polym ; 261: 117883, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766370

RESUMO

A new biosorbent Ca-crosslinked pectin/lignocellulose nanofibers/chitin nanofibers (PLCN) was synthesized for cholesterol and bile salts adsorption from simulated intestinal fluid during gastric-intestinal passage. The physico-chemical properties of PLCN were studied using SEM, FTIR, XRD, DSC and BET. Before gastrointestinal passage, PLCN had an amorphous single-phase, compact structure formed via hydrogen and van der Waals bonds that revealed an irregular shape with the shriveled surface but watery condition and enzymatic digestion led to create a porous structure without destruction because of the water-insoluble nanofibers, therefore increasing the adsorption capacity. The maximum adsorption capacity reached 37.9 and 5578.4 mg/g for cholesterol and bile salts, respectively. Freundlich isotherm model indicated the reversible heterogeneous adsorption of both cholesterol and bile salts on PLCN. Further, their adsorption followed pseudo-second order kinetic model. These results suggest that PLCN has potential as a gastrointestinal-resistant biosorbent for cholesterol and bile salts adsorption applicable in medicine and food industry.


Assuntos
Ácidos e Sais Biliares/farmacocinética , Quitina/química , Colesterol/farmacocinética , Lignina/química , Nanofibras/química , Pectinas/química , Absorção Fisico-Química/efeitos dos fármacos , Adsorção/efeitos dos fármacos , Quitina/farmacocinética , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Humanos , Técnicas In Vitro , Cinética , Lignina/farmacocinética , Nanocompostos/análise , Nanocompostos/química , Pectinas/farmacocinética
2.
Nutrients ; 11(12)2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31888255

RESUMO

Polyphenols are widely acknowledged for their health benefits, especially for the prevention of inflammatory and age-related diseases. We previously demonstrated that hydroxytyrosol (HT) and procyanidins (PCy), alone or in combination, drive preventive anti-osteoathritic effects in vivo. However, the lack of sufficient clinical evidences on the relationship between dietary phytochemicals and osteoarthritis remains. In this light, we investigated in humans the potential osteoarticular benefit of a grapeseed and olive extract (OPCO) characterized for its hydroxytyrosol (HT) and procyanidins (PCy) content. We first validated, in vitro, the anti-inflammatory and chondroprotective properties of the extract on primary cultured human articular chondrocytes stimulated by interleukin-1 beta (IL-1 ß). The sparing effect involved a molecular mechanism dependent on the nuclear transcription factor-kappa B (NF-κB) pathway. To confirm the clinical relevance of such a nutritional strategy, we designed an innovative clinical approach taking into account the metabolites that are formed during the digestion process and that appear in circulation after the ingestion of the OPCO extract. Blood samples from volunteers were collected following ingestion, absorption, and metabolization of the extract and then were processed and applied on human primary chondrocyte cultures. This original ex vivo methodology confirmed at a clinical level the chondroprotective properties previously observed in vitro and in vivo.


Assuntos
Absorção Fisico-Química/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Condrócitos/efeitos dos fármacos , Extrato de Sementes de Uva/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Adulto , Células Cultivadas , Voluntários Saudáveis , Humanos , Interleucina-1beta/sangue , Masculino , NF-kappa B/sangue , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/farmacologia , Proantocianidinas/farmacologia , Adulto Jovem
3.
J Tradit Chin Med ; 39(5): 609-623, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-32186110

RESUMO

OBJECTIVE: To examine changes in the morphology and physiological functions of human proximal tubular epithelial cells (HK-2 cells) caused by total Dahuang (Radix Et Rhizoma Rhei Palmati) anthraquinones (TDA) and emodin. METHODS: HK-2 cells were cultured on polycarbonate (PCF) membranes to form a complete monolayer of cells. A fluorescein isothiocyanate-dextran (FITC) permeability assay was conducted and secretion of γ-glutamyltranspeptidase (GGT), lactate dehydrogenase (LDH), N-acetyl-ß-D-glucosaminidase (NAG) and kidney injury molecule 1 (KIM-1) was examined. The reabsorption of glucose and the excretion of para-aminohippuric acid (PAH) by HK-2 cells were also examined. The morphology of HK-2 cells was observed using optical microscopy and scanning electron microscopy. The cytoskeleton of HK-2 cells was observed under a fluorescence microscope. RESULTS: Compared with the results for the dimethyl sulfoxide group, treatment of cells with TDA and emodin showed statistically significant differences in the FITC leakage rate, the apical / basolateral ratio of LDH and GGT, and the secretion of GGT, LDH, NAG and KIM-1. At 64 µg/mL, TDA markedly inhibited blood glucose reabsorption and remarkably suppressed PAH excretion by HK-2 cells. Both TDA and emodin caused various degrees of damage to the morphology and cytoskeleton of HK-2 cells with the degree of damage correlating positively with the dosage of the tested substances. CONCLUSION: Both TDA and emodin caused damage to human renal proximal tubular epithelial cells at certain dosages. At the same dosage, TDA caused more severe damage than emodin to the HK-2 cells.


Assuntos
Antraquinonas/efeitos adversos , Emodina/efeitos adversos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Túbulos Renais Proximais/citologia , Rheum/química , Absorção Fisico-Química/efeitos dos fármacos , Actinas/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , L-Lactato Desidrogenase/metabolismo , Proteínas de Neoplasias/metabolismo , gama-Glutamiltransferase/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-26930688

RESUMO

The human colorectal carcinoma cell line (Caco-2) is a commonly used in-vitro test that predicts the absorption potential of orally administered drugs. In-silico prediction methods, based on the Caco-2 assay data, may increase the effectiveness of the high-throughput screening of new drug candidates. However, previously developed in-silico models that predict the Caco-2 cellular permeability of chemical compounds use handcrafted features that may be dataset-specific and induce over-fitting problems. Deep Neural Network (DNN) generates high-level features based on non-linear transformations for raw features, which provides high discriminant power and, therefore, creates a good generalized model. We present a DNN-based binary Caco-2 permeability classifier. Our model was constructed based on 663 chemical compounds with in-vitro Caco-2 apparent permeability data. Two hundred nine molecular descriptors are used for generating the high-level features during DNN model generation. Dropout regularization is applied to solve the over-fitting problem and the non-linear activation. The Rectified Linear Unit (ReLU) is adopted to reduce the vanishing gradient problem. The results demonstrate that the high-level features generated by the DNN are more robust than handcrafted features for predicting the cellular permeability of structurally diverse chemical compounds in Caco-2 cell lines.


Assuntos
Absorção Fisico-Química/efeitos dos fármacos , Aprendizado Profundo , Modelos Estatísticos , Preparações Farmacêuticas/metabolismo , Células CACO-2 , Permeabilidade da Membrana Celular/efeitos dos fármacos , Biologia Computacional , Simulação por Computador , Avaliação Pré-Clínica de Medicamentos , Humanos
5.
J Inorg Biochem ; 181: 139-144, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28967474

RESUMO

The aim of this study was to determine the content, distribution and behaviour of Al in soils under beech forest with different parent rock, and to assess the role of herbaceous vegetation on soil Al behaviour. We hypothesize that the contents of elements in the soil sorption complex (Al etc.) are strongly influenced by vegetation cover. Also, low molecular mass organic acids (LMMOA) can be considered as an indicator of soil organic matter (SOM) decomposition and vegetation litter turnover. Speciation of LMMOA, nutrition content (PO43-, Ca2+, K+) and element composition in aqueous extracts were determined by means of ion chromatography and inductively coupled plasma - optical emission spectrometry (ICP-OES) respectively. Active and exchangeable pH, sorption characteristics and exchangeable Al (Alex) were determined in BaCl2 extracts by ICP-OES. Elemental composition of parent rocks was assessed by means of X-ray fluorescence spectroscopy. Herb-poor localities showed lower pH, less nutrients (PO43-, Ca2+, K+), less LMMOA, a larger stock of SOM and greater cation exchange capacity. There was also lower mobilisation of Al in organic horizons, which explains the larger pools of Al. Generally, we can conclude that LMMOA, and thus soil vegetation cover, play an important role in the Al soil cycle.


Assuntos
Alumínio/toxicidade , Quelantes/química , Sedimentos Geológicos/química , Desenvolvimento Vegetal/efeitos dos fármacos , Plantas Medicinais/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Absorção Fisico-Química/efeitos dos fármacos , Absorção Fisiológica/efeitos dos fármacos , Alumínio/análise , Alumínio/química , Alumínio/metabolismo , Quelantes/análise , República Tcheca , Fagus/química , Fagus/efeitos dos fármacos , Fagus/crescimento & desenvolvimento , Fagus/metabolismo , Florestas , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Peso Molecular , Plantas/efeitos dos fármacos , Plantas/metabolismo , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/metabolismo , Poluentes do Solo/análise , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Solubilidade
6.
Lancet Haematol ; 4(11): e524-e533, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29032957

RESUMO

BACKGROUND: Current guidelines to treat iron deficiency recommend daily provision of ferrous iron divided through the day to increase absorption. However, daily dosing and split dosing might increase serum hepcidin and decrease iron absorption from subsequent doses. Our study aim was to compare iron absorption from oral iron supplements given on consecutive versus alternate days and given as single morning doses versus twice-daily split dosing. METHODS: We did two prospective, open-label, randomised controlled trials assessing iron absorption using (54Fe)-labelled, (57Fe)-labelled, or (58Fe)-labelled ferrous sulfate in iron-depleted (serum ferritin ≤25 µg/L) women aged 18-40 years recruited from ETH Zurich and the University of Zurich, Switzerland. In study 1, women were randomly assigned (1:1) to two groups. One group was given 60 mg iron at 0800 h (±1 h) on consecutive days for 14 days, and the other group was given the same doses on alternate days for 28 days. In study 2, women were assigned to two groups, stratified by serum ferritin so that two groups with similar iron statuses could be formed. One group was given 120 mg iron at 0800 h (±1 h) and the other was given the dose split into two divided doses of 60 mg at 0800 h (±1 h) and 1700 h (±1 h) for three consecutive days. 14 days after the final dose, the groups were each crossed over to the other regimen. Within-individual comparisons were done. The co-primary outcomes in both studies were iron bioavailability (total and fractional iron absorption), assessed by measuring the isotopic label abundance in erythrocytes 14 days after administration, and serum hepcidin. Group allocations in both studies were not masked and primary and safety analyses were done on an intention-to-treat basis. The studies were registered at ClinicalTrials.gov, numbers NCT02175888 (study 1) and NCT02177851 (study 2) and are complete. FINDINGS: For study 1, 40 women were enrolled on Oct 15-29, 2015. 21 women were assigned to the consecutive-day group and 19 to the alternate-day group. At the end of treatment (14 days for the consecutive-day group and 28 days for the alternate-day group), geometric mean (-SD, +SD) cumulative fractional iron absorptions were 16·3% (9·3, 28·8) in the consecutive-day group versus 21·8% (13·7, 34·6) in the alternate-day group (p=0·0013), and cumulative total iron absorption was 131·0 mg (71·4, 240·5) versus 175·3 mg (110·3, 278·5; p=0·0010). During the first 14 days of supplementation in both groups, serum hepcidin was higher in the consecutive-day group than the alternate-day group (p=0·0031). In study 2, 20 women were enrolled between Aug 13 and 18, 2015. Ten women were assigned to receive once-daily dosing and ten were assigned to receive twice-daily divided dosing. No significant differences were seen in fractional (day 1-3 geometric mean: 11·8% [7·1, 19·4] once daily vs 13·1% [8·2, 20·7] twice daily; p=0·33) or total iron absorption (day 1-3: 44·3 mg [29·4, 66·7] once daily vs 49·4 [35·2, 69·4] twice daily; p=0·33) between the two dosing regimens. Twice-daily divided doses resulted in a higher serum hepcidin concentration than once-daily dosing (p=0·013). No grade 3 or 4 adverse events were reported in either study. INTERPRETATION: In iron-depleted women, providing iron supplements daily as divided doses increases serum hepcidin and reduces iron absorption. Providing iron supplements on alternate days and in single doses optimises iron absorption and might be a preferable dosing regimen. These findings should be confirmed in iron-deficient anaemic patients. FUNDING: Swiss National Science Foundation, Bern, Switzerland.


Assuntos
Absorção Fisico-Química/efeitos dos fármacos , Ferro/administração & dosagem , Ferro/metabolismo , Administração Oral , Adolescente , Adulto , Esquema de Medicação , Feminino , Hepcidinas/sangue , Humanos , Ferro/farmacologia , Deficiências de Ferro , Masculino , Adulto Jovem
7.
Environ Res ; 138: 298-305, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25749125

RESUMO

OBJECTIVE: To evaluate the association between mercury exposure and thyroid-stimulating hormone (TSH), total triiodothyronine (TT3) and free thyroxine (FT4) levels during pregnancy as well as to explore if there is any synergic action between mercury and intake of iodine from different sources. METHODS: The study population was 1407 pregnant women participating in the Spanish INMA birth cohort study. Total mercury concentrations were analyzed in cord blood. Thyroid hormones (THs) were measured in serum samples collected at 13.2±1.5 weeks of gestation. The association between mercury and TH levels was evaluated with multivariate linear regression models. Effect modification caused by iodine intake from supplements and diet was also evaluated. RESULTS: The geometric means of TSH, TT3, FT4 and mercury were 1.1µU/L, 2.4nmol/L, 10.5pmol/L and 7.7µg/L, respectively. Mercury levels were marginally significantly associated with TT3 (ß: -0.05; 95%CI: -0.10, 0.01), but were neither associated with TSH nor FT4. The inverse association between mercury and TT3 levels was stronger among the iodine supplement consumers (-0.08; 95%CI: -0.15, -0.02, interaction p-value=0.07). The association with FT4 followed the same pattern, albeit not significant. CONCLUSION: Prenatal mercury exposure was inversely associated with TT3 levels among women who took iodine supplements during pregnancy. These results could be of public health concern, although further research is needed.


Assuntos
Suplementos Nutricionais , Exposição Ambiental , Iodo/farmacologia , Mercúrio/sangue , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Absorção Fisico-Química/efeitos dos fármacos , Adulto , Estudos de Coortes , Monitoramento Ambiental , Feminino , Sangue Fetal/química , Fluorimunoensaio , Humanos , Gravidez , Espanha , Espectrofotometria Atômica
8.
Med Hypotheses ; 84(5): 451-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25682188

RESUMO

The recent Trial to Assess Chelation Therapy (TACT) study, enrolling subjects who had previously experienced a myocardial infarction, has provided strong evidence that intravenous chelation therapy can markedly reduce risk for mortality and vascular events in diabetics, whereas no discernible benefit was observed in non-diabetics. It has plausibly been suggested that this reflects a role for transition metal ions--iron or copper--in the genesis of advanced glycation end products, key mediators of diabetic complications that can destabilize plaque. Since phlebotomy therapy fails to prevent vascular events in diabetics, we hypothesize that labile copper may be the chief culprit whose removal by chelation mediated the benefit observed in TACT. If so, strategies less time and labor intensive than chelation therapy might provide comparable benefit. A number of recent studies report that the copper-specific orally-active chelator trientine can reduce risk for range of diabetic complications in rodents; a clinical trial with this agent demonstrated some decrease in left ventricular mass in diabetics with ventricular hypertrophy. However, until this agent becomes less expensive, supplementation with high-dose zinc may represent a more feasible alternative. Zinc opposes the absorption and redox activity of copper via induction of the antioxidant protein metallothionein, which binds copper tightly. A great many studies demonstrate that increased expression of metallothionein decreases risk for tissue damage in diabetic rodents, and in some of these studies metallothionein expression was boosted by supplemental zinc. Zinc supplementation also modestly improves glycemic control in type 2 diabetics, and might reduce risk for diabetes by protecting pancreatic beta cells from oxidative stress. A long term study assessing the impact of supplementing diabetics with high-dose zinc, assessing risk for mortality, vascular events, and diabetic complications, may be warranted. Histidine, which readily forms complexes with copper that possess superoxide dismutase activity, also has potential for alleviating the contribution of loosely bound copper to AGE formation; moreover, in a recent clinical study, supplemental histidine improved insulin sensitivity and exerted anti-inflammatory and antioxidant effects in women with metabolic syndrome. Since ascorbate can reduce labile copper and thereby enhance its pathogenicity, the impact of high-dose ascorbate supplementation on cardiovascular risk in diabetics should receive further study.


Assuntos
Terapia por Quelação/métodos , Complicações do Diabetes , Infarto do Miocárdio/complicações , Infarto do Miocárdio/prevenção & controle , Zinco/uso terapêutico , Absorção Fisico-Química/efeitos dos fármacos , Cobre , Suplementos Nutricionais , Feminino , Humanos , Oxirredução/efeitos dos fármacos , Zinco/farmacologia
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