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1.
Antioxidants (Basel) ; 12(9)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37759972

RESUMO

Limited scientific evidence shows that alpha lipoic acid (ALA) can induce regression rates of low-grade squamous intraepithelial lesions (LSILs), but the mechanisms of these effects have not been elucidated. To gain a broader insight into its therapeutic potential and mechanisms of action, the effects of 3 months of supplementation with 600 mg of ALA on antioxidant and lipid status parameters in 100 patients with LSILs were investigated in a randomized, placebo-controlled study. The obtained results are discussed in terms of patients' initial metabolic status and diet quality (particularly nutritional intake of antioxidants). The obtained results showed that oxidative status biomarkers were not significantly affected by ALA supplementation. However, serum superoxide dismutase (SOD) activity was positively affected in the subgroup of patients with higher dietary antioxidant intake. Surprisingly, ALA supplementation resulted in a small but statistically significant increase in serum low density lipoprotein (LDL), and the observed effect was significantly affected by the initial lipid status of the participants. Larger studies are necessary to gain additional insights on the clinical significance of ALA as an antioxidant and hypolipemic agent and to optimize its potential application in LSIL treatment.

2.
Foods ; 12(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36900634

RESUMO

Raw and purified mandarin peel-derived pectins were characterized and combined with olive pomace extract (OPE) in the green synthesis of selenium nanoparticles (SeNPs). SeNPs were characterized in terms of size distribution and zeta potential, and their stability was monitored during 30 days of storage. HepG2 and Caco-2 cell models were used for the assessment of biocompatibility, while antioxidant activity was investigated by the combination of chemical and cellular-based assays. SeNP average diameters ranged from 171.3 nm up to 216.9 nm; smaller SeNPs were obtained by the utilization of purified pectins, and functionalization with OPE slightly increased the average. At concentrations of 15 mg/L SeNPs were found to be biocompatible, and their toxicity was significantly lower in comparison to inorganic selenium forms. Functionalization of SeNPs with OPE increased their antioxidant activity in chemical models. The effect was not clear in cell-based models, even though all investigated SeNPs improved cell viability and protected intracellular reduced GSH under induced oxidative stress conditions in both investigated cell lines. Exposure of cell lines to SeNPs did not prevent ROS formation after exposure to prooxidant, probably due to low transepithelial permeability. Future studies should focus on further improving the bioavailability/permeability of SeNPs and enhancing the utilization of easily available secondary raw materials in the process of phyto-mediated SeNP synthesis.

3.
Healthcare (Basel) ; 10(12)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36553960

RESUMO

Low-grade squamous intraepithelial lesion (SIL) is a cytologic diagnosis etiologically related to human papilloma virus (HPV) infection that leads to the release of inflammation mediators, the formation of reactive oxygen species (ROS) and decreased levels of antioxidants in tissues, which is why antioxidants might be considered effective against SIL progression. This randomized double-blind placebo-controlled study aimed to investigate the effectiveness of alpha-lipoic acid (ALA) supplementation (600 mg/day) on the regression of low-grade SIL in 100 patients. Low-grade SIL was determined after the cytological screening, colposcopic examination and targeted biopsy and histological confirmation of cytological−colposcopic diagnosis. Inflammation parameters and the presence of HPV were determined by standard laboratory methods. Dietary and lifestyle habits were investigated using a standardized and validated semi-quantitative food questionnaire (FFQ). ALA supplementation significantly reduced the proportion of patients with low-grade cytological abnormalities, in comparison to placebo. Given the obtained level of significance (p < 0.001), the presented results indicate that short-term ALA supplementation shows a clinically significant effect on cervical cytology. Future studies should focus on the use of innovative formulations of ALA that might induce bioavailability and therapeutic efficiency against HPV infection and the investigation of synergistic effects of concurrent dietary/lifestyle modification and ALA supplementation in both low-grade and high-grade SIL.

4.
Int J Mol Sci ; 23(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36012394

RESUMO

Olive pomace extract (OPE) was investigated as a potential surface modifier for the development of the green synthesis process of selenium nanoparticles (SeNPs). In order to evaluate them as potential nutraceuticals, the obtained nanosystems were characterized in terms of size distribution, shape, zeta potential, stability in different media, gastrointestinal bioaccessibility and biocompatibility. Systems with a unimodal size distribution of spherical particles were obtained, with average diameters ranging from 53.3 nm to 181.7 nm, depending on the type of coating agent used and the presence of OPE in the reaction mixture. The nanosystems were significantly affected by the gastrointestinal conditions. Bioaccessibility ranged from 33.57% to 56.93% and it was significantly increased by functionalization of with OPE. Biocompatibility was investigated in the HepG2 and Caco2 cell models, proving that they had significantly lower toxicity in comparison to sodium selenite. Significant differences were observed in cellular responses depending on the type of cells used, indicating differences in the mechanisms of toxicity induced by SeNPs. The obtained results provide new insight into the possibilities for the utilization of valuable food-waste extracts in the sustainable development of nanonutraceuticals.


Assuntos
Nanopartículas , Olea , Selênio , Antioxidantes/química , Células CACO-2 , Humanos , Nanopartículas/química , Selênio/química
5.
Foods ; 9(12)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317079

RESUMO

BACKGROUND: olive pomace extract (OPE) is a rich source of health promoting polyphenols (hydroxytyrosol (HTS) and tyrosol (TS)) and can be used as a nutraceutical ingredient of dietary supplements and functional foods. Its adequate bioavailability is a prerequisite for excreting biological activity and can be significantly and specifically affected by different food matrices. METHODS: in order to investigate food effects on polyphenol bioaccessibility, OPE was co-digested with different foods according to internationally harmonized in vitro digestibility method. Impact of particular nutrients on HTS and TS permeability was assessed on Caco-2 cell monolayer. RESULTS: HTS and TS bioaccessibility and transepithelial permeability can be significantly affected by foods (nutrients), especially by casein and certain types of dietary fiber. Those effects are polyphenol-and nutrient-specific and are achieved either through complexation in gastrointestinal lumen and/or through direct effects of nutrients on intestinal monolayer. CONCLUSIONS: obtained results emphasize the significance and complexity of polyphenol interactions within the food matrix and the necessity of individual investigational approaches with respect to particular food/nutrient and interacting phenolic compounds.

6.
J Cancer Res Clin Oncol ; 146(11): 2967-2978, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32507973

RESUMO

PURPOSE: This study investigated the frequency and characteristics of sarcopenia among patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT) with a specific focus on the chronic graft-versus-host disease (cGVHD) population and its association with malnutrition, vitamin D and clinical characteristics. METHODS: We assessed sarcopenia, vitamin D levels, and nutritional status in 73 patients who underwent allo-HSCT, of which 45 were diagnosed with cGVHD. Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older People (EWGSOP) criteria. RESULTS: Sarcopenia was diagnosed in 19.2% of patients after allo-HSCT with statistically no significant difference between cGVHD and non-cGVHD patients. The risk factor for sarcopenia was the male gender. Sarcopenia in allo-HSCT patients correlated strongly with malnutrition and with current corticosteroid treatment (p < 0.005). Among cGVHD patients sarcopenia additionally correlated strongly with the number of prior systemic immunosuppressive therapy lines (p < 0.005) and moderately with the intensity of immunosuppression, cGVHD severity global rating assessed by both the health care provider and the patient and joint and fascia cGVHD involvement (p < 0.05). Vitamin D deficiency was found in more than 54.8% of patients, but the correlation to sarcopenia was not found. CONCLUSION: Sarcopenia was found to be common in long term survivors of allo-HSCT independently of the cGVHD diagnosis. Prospective longitudinal studies are needed for a better understanding of factors affecting the development of sarcopenia after allo-HSCT.


Assuntos
Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Sarcopenia/epidemiologia , Adulto , Idoso , Aloenxertos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Sarcopenia/etiologia , Vitamina D/sangue , Adulto Jovem
7.
Nutrients ; 12(3)2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32121413

RESUMO

Olive pomace is a rich source of biologically active compounds, mainly polyphenols. Recently, an efficient and sustainable cyclodextrin (CD)-enhanced extraction was developed. It enabled a relatively simple formulation of high-quality olive pomace extracts (OPEs) that can be used as alternative sources of olive-derived polyphenols in the nutrition and pharma industries. However, biological effects and nutraceutical potential of OPEs are primarily limited by generally low oral bioavailability of major polyphenols (hydroxytyrosol and its derivatives) that can be significantly influenced by OPE matrix and the presence of CDs in formulation. The major goal of this research was to investigate the impact of complex matrix and different types of CDs on gastrointestinal stability and intestinal permeability of major OPE polyphenols, and provide additional data about mechanisms of absorption and antioxidant activity in gut lumen. Obtained results showed high bioaccessibility but relatively low permeability of OPE polyphenols, which was negatively affected by OPE matrix. CDs improved antioxidant efficiency of tested OPEs and tyrosol gastrointestinal stability. Effects of CDs on permeability and the metabolism of particular OPE polyphenols were CD- and polyphenol-specific.


Assuntos
Antioxidantes/farmacocinética , Suplementos Nutricionais , Portadores de Fármacos/química , Olea/química , Extratos Vegetais/farmacocinética , Polifenóis/farmacocinética , Administração Oral , Antioxidantes/administração & dosagem , Disponibilidade Biológica , Células CACO-2 , Ciclodextrinas/química , Composição de Medicamentos/métodos , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Permeabilidade , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem
8.
Molecules ; 23(8)2018 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-30126204

RESUMO

Waste remaining after the production of olive oil (olive pomace) is known to contain significant amounts of phenolic compounds that exert different types of biological activities, primarily acting as antioxidants. In this work, a sustainable approach that combines ultrasound-assisted extraction with food-grade solvents and encapsulation with different types of cyclodextrins was used to prepare olive pomace-based polyphenol rich extracts that were tested as antioxidants in various chemical, food, and biological model systems. Encapsulation with cyclodextrins had a significant positive impact on the chemical composition of obtained extracts and it positively affected their antioxidant activity. Observed effects can be explained by an increased content of polyphenols in the formulations, specific physical properties of encapsulated compounds improving their antioxidant activity in complex food/physiological environment, and enhanced interaction with natural substrates. Depending on the applied model, the tested samples showed significant antioxidant protection in the concentration range 0.1⁻3%. Among the investigated cyclodextrins, hydroxypropyl-ß-cyclodextrin and randomly methylated-ß-cyclodextrin encapsulated extracts showed particularly good antioxidant activity and were especially potent in oil-in-water emulsion systems (1242 mg/g and 1422 mg/g of Trolox equivalents, respectively), showing significantly higher antioxidant activity than Trolox (reference antioxidant). In other models, they provided antioxidant protection comparable to commonly used synthetic antioxidants at concentration levels of 2⁻3%.


Assuntos
Antioxidantes/análise , Antioxidantes/química , Suplementos Nutricionais , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Peroxidação de Lipídeos/efeitos dos fármacos , Olea/química , Azeite de Oliva/análise , Azeite de Oliva/química , Fenóis/análise , Fosfatidiletanolaminas/química , Compostos Fitoquímicos/química , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Óleos de Plantas/análise , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
9.
Food Chem ; 246: 394-403, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29291864

RESUMO

Organic products are generally recognized to be healthier and safer than conventional products. However, the actual scientific data regarding the importance of organic production on particular contaminant/additive content of wines is scarce. This study aimed to evaluate contents of pesticides, metals, sulphites and ochratoxin A in organically (org) and conventionally (conv) produced wines from eleven locations in different winegrowing regions of Croatia. All wines contained significantly lower levels of residues as compared to the maximum limits (MLs) with the exception of excessive amounts of Cu and Zn in one sample. Pb and Mg were mainly significantly less represented in org wines. There were no significant differences in the content of sulphite or ochratoxin A between org and conv wines. Significantly lower total pesticide concentrations and average number of pesticides per sample were obtained in org wines. The majority of ochratoxin A positive wines were from conv wine producers.


Assuntos
Alimentos Orgânicos/análise , Metais/análise , Ocratoxinas/análise , Praguicidas/análise , Sulfitos/análise , Vinho/análise , Croácia , Contaminação de Alimentos/análise
10.
Food Chem ; 200: 98-106, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26830566

RESUMO

A new multiresidue method was developed for determination of 25 pesticide residues in red wine by gas chromatography coupled to mass spectrometry with a single run of 23.63 min. Samples were extracted from wine with solid phase extraction using Oasis HLB. Mixture of methanol and water was used for rinsing, while acetonitrile and n-hexane were used as elution solvents. Method was validated according to SANCO/12571/2013 criteria in wide linearity range (limit of quantification - 400 µg L(-1)). Limits of quantification (LOQ) were well below 10 µg L(-1) for most pesticides and recoveries at 2×LOQ and 10×LOQ concentration levels were in range 70-120%. Precision, expressed as a relative standard deviation, was always under 14%. The method was applied to 32 red wine samples from Croatia. Pesticides were detected in 30 samples with a total of 15 pesticides found, 7 of which were at a high concentration.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/química , Extração em Fase Sólida/métodos , Vinho/análise , Vinho/parasitologia
11.
J Am Coll Nutr ; 35(3): 224-35, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25989426

RESUMO

OBJECTIVE: The aim of this work was to evaluate the combined effect of physical activity and 1 and 12 months' adherence to Mediterranean diet (MD) on serum total antioxidant capacity (TAC) in obese patients, as well as factors contributing to TAC. METHODS: One hundred twenty-four patients were randomly assigned to either MD combined with physical activity or standard hypolypemic diet (SHD) with physical activity. Both groups received counseling and education during the initial week and were invited for the follow-up visits, where data on body weight and blood samples were collected. TAC was determined by Trolox equivalent antioxidant capacity and urate was determined using a uricase spectrophotometric method at the initial visit and after 1 and 12 months. RESULTS: Eighty-four patients finished the 12-month program and were analyzed. The baseline and 1- and 12-month mean (±SD) TAC values in the MD group (n = 40) were 2.38 ± 0.48, 2.51 ± 0.47, and 2.47 ± 0.45 mmol Trolox equivalent (TE)/L, respectively. In the SHD group (n = 44), TAC values were 2.37 ± 0.49, 2.48 ± 0.49, and 2.31 ± 0.51 mmol TE/L, respectively. There was a statistically significant main effect for time (p < 0.001), as well as statistically significant time-diet interaction effect (p = 0.009). There was no statistically significant correlation between TAC and uric acid after 1 month (p = 0.733) or 12 months (p = 0.844) of the intervention. Based on the regression model, which included gender, diet, physical activity level, and percentage body weight change, the type of diet was the only significantly contributing factor to TAC change after the 12-month period, F = 3.867, df = 3, p = 0.012, R = 0.358, R(2) = 0.128. CONCLUSION: This randomized controlled trial with diet and physical activity intervention and TAC as a primary outcome demonstrated initial antioxidant improvement in both MD and SHD groups and a long-term beneficial effect of MD. The results imply that diet composition-olive oil, nuts, and fish in particular-combined with physical activity modify antioxidant capacity.


Assuntos
Antioxidantes/metabolismo , Dieta Mediterrânea , Obesidade/metabolismo , Adolescente , Adulto , Idoso , Carboidratos da Dieta/farmacologia , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/dietoterapia , Adulto Jovem
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