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1.
Molecules ; 29(6)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38542896

RESUMO

The effects of high-pressure processing (HPP) (450 MPa/600 MPa/3 min) on the carotenoid and vitamin E contents of smoothies made from strawberry, orange juice, banana and apple, and the same smoothies enriched with dietary fiber from discarded carrots were compared. The contents and bioaccessibilities of these compounds were also evaluated over the course of 28 days at 4 °C. The application of HPP in the formulations significantly increased the contents of ß-cryptoxanthin, α-carotene and ß-carotene and retained the contents of lutein, zeaxanthin and vitamin E compared to untreated samples. A decreasing trend in the content of each compound was observed with an increase in storage time. The application of HPP initially led to reductions in the bioaccessibility of individual compounds. However, overall, during storage, there was an increase in bioaccessibility. This suggests that HPP influences cell structure, favoring compound release and micelle formation. HPP is a sustainable method that preserves or enhances carotenoid extractability in ready-to-drink fruit beverages. Furthermore, the incorporation of dietary fiber from carrot processing discards supports circular economy practices and enhances the health potential of the product.


Assuntos
Daucus carota , Daucus carota/metabolismo , Vitamina E/análise , Frutas/química , Carotenoides/análise , Fibras na Dieta/análise
2.
Am J Pathol ; 192(10): 1448-1457, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35843264

RESUMO

Spinal cord injury (SCI) is associated with venous vascular dysfunction below the level of injury, resulting in dysregulation of tissue fluid homeostasis in afflicted skin. The purpose of this study was to determine whether loss of neuronal control in chronic SCI also affects the skin lymphatic system. Morphology of lymphatics was characterized by immunohistochemistry and lymphatic gene expression profiles determined by DNA microarray analysis. In SCI, skin lymphatic function appeared to be impaired, because the ratio of functionally dilated versus collapsed lymphatic vessels was decreased 10-fold compared with control. Consequently, the average lumen area of lymphatic vessels was almost halved, possibly due to the known impaired connective tissue integrity of SCI skin. In fact, collagenases were found to be overexpressed in SCI skin, and dermal collagen structure was impaired. Molecular profiling also suggested an SCI-specific phenotype of increased connective tissue turnover and decreased lymphatic contractility. The total number of lymphatic vessels in SCI skin, however, was doubled, pointing to enhanced lymphangiogenesis. In conclusion, these data show, for the first time, that lymphatic function and development in human skin are under neuronal control. Because peripheral venous and lymphatic vascular defects are associated with disturbed fluid homeostasis, inappropriate wound healing reactions, and impaired skin immunity, they might contribute to the predisposition of afflicted individuals to pressure ulcer formation and wound healing disorders.


Assuntos
Vasos Linfáticos , Traumatismos da Medula Espinal , DNA/metabolismo , Humanos , Linfangiogênese , Sistema Linfático , Vasos Linfáticos/metabolismo , Medula Espinal , Traumatismos da Medula Espinal/metabolismo
3.
Crit Rev Food Sci Nutr ; 62(8): 1999-2049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33399015

RESUMO

Carotenoids are isoprenoids widely distributed in foods that have been always part of the diet of humans. Unlike the other so-called food bioactives, some carotenoids can be converted into retinoids exhibiting vitamin A activity, which is essential for humans. Furthermore, they are much more versatile as they are relevant in foods not only as sources of vitamin A, but also as natural pigments, antioxidants, and health-promoting compounds. Lately, they are also attracting interest in the context of nutricosmetics, as they have been shown to provide cosmetic benefits when ingested in appropriate amounts. In this work, resulting from the collaborative work of participants of the COST Action European network to advance carotenoid research and applications in agro-food and health (EUROCAROTEN, www.eurocaroten.eu, https://www.cost.eu/actions/CA15136/#tabs|Name:overview) research on carotenoids in foods and feeds is thoroughly reviewed covering aspects such as analysis, carotenoid food sources, carotenoid databases, effect of processing and storage conditions, new trends in carotenoid extraction, daily intakes, use as human, and feed additives are addressed. Furthermore, classical and recent patents regarding the obtaining and formulation of carotenoids for several purposes are pinpointed and briefly discussed. Lastly, emerging research lines as well as research needs are highlighted.


Assuntos
Carotenoides , Alimentos , Antioxidantes , Carotenoides/análise , Dieta , Humanos , Vitamina A
4.
Int Wound J ; 18(5): 728-737, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33723924

RESUMO

Patients with spinal cord injury have a predisposition to develop pressure ulcers. Specific characteristics of the patients' skin potentially involved have not yet been identified. The purpose of this investigation was to determine whether loss of neuronal control affects cellular and molecular homeostasis in the skin. Intact afflicted skin, wound edge of pressure ulcers, and control skin were analysed. Platelets, transforming growth factor-ß1, and activin A were identified by immunohistochemistry. Transforming growth factor-ß-like activity was determined by bioassay, and gene expression by DNA microarray analysis or RT-PCR. In afflicted skin, enhanced platelet extravasation was detected. Transforming growth factor-ß1 and activin A accumulated in the dermal-epidermal junction zone. Transforming growth factor-ß-like activity and activin A expression were increased in intact afflicted skin (compared to control skin) and were further enhanced in pressure ulcers. In vitro, activity was generated by fibroblast-epithelial cell interactions, which also induced activin A. Thus, loss of neuronal control in spinal cord injury appears to trigger inappropriate wound healing processes in the patients' skin. Plasma leakage and increased transforming growth factor-ß-like activity combined with shear forces potentially enhance the risk for pressure ulcer formation.


Assuntos
Úlcera por Pressão , Traumatismos da Medula Espinal , Humanos , Pele , Fator de Crescimento Transformador beta , Cicatrização
5.
Int J Vitam Nutr Res ; 89(5-6): 337-347, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30932779

RESUMO

This study was conducted to analyse antioxidant potencies, vitamin C contents, polyphenol profiles, antidiabetic and anti-inflammatory potencies of citrus fruits from Indonesia. Total phenolics contents (TPC) of seven citrus fruits from northern Aceh, Indonesia, were measured using Folin-Ciocalteu (FC) and Fast Blue BB (FBBB) methods. Total flavonoid content (TFC) test showed for peel and pulp extracts of calung and jeruk takengon (local mandarin) the highest values. H-TEAC (hydrophilic trolox equivalent antioxidant capacity) and H-ORAC (hydrophilic oxygen reactive absorbance capacity) antioxidant capacity were highest for peel and pulp of jeruk takengon, calung and kruet mameh. Interestingly, peel extracts showed no α-amylase inhibition activity whilst pulp showed weak inhibitory activity. Polyphenol composition was dominated by flavanones, with hesperidin and neohesperidin as main flavanones (hesperidin: 131-5433 mg/100 g DW, neohesperidin: 431-4131 mg/100 g DW). Vitamin C contents were highly correlated with antioxidant capacities in pulp (R2 = 0.95 and R2 = 0.94 at p < 0.01 for H-TEAC and H-ORAC, respectively), and TPC and TFC were highly correlated with antioxidant capacities (R2 = 0.99 and R2 = 0.98 for TPC FC in pulp and R2 = 0.93 and R2 = 0.84 in peel for H-TEAC and H-ORAC, respectively; R2 = 0.88 and R2 = 0.80 in pulp, and R2 = 0.68 and R2 = 0.75 for TFC in peel for H-TEAC and H-ORAC at p < 0.01). In-vitro COX-2 inhibitory activity tests resulted in higher activity for pulp compared to the corresponding peel extracts except for calung. Pulp extract of jeruk takengon showed the highest activity. In general, local citrus fruits from Aceh, Indonesia, are potential sources of polyphenols and vitamin C.


Assuntos
Citrus , Antioxidantes , Ácido Ascórbico , Ciclo-Oxigenase 2 , Frutas , Indonésia , Extratos Vegetais , Polifenóis , alfa-Amilases
7.
Chem Biodivers ; 14(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28865183

RESUMO

Composition of tocopherols, tocotrienols, carotenoids, fatty acids, as well as hydrophilic and lipophilic antioxidant activities, were determined in seeds of two Salvia species and oils obtained from them. Both seeds contained a large amount of oil (around 20%) rich in polyunsaturated fatty acids. While Salvia officinalis seed oil can be classified as oleic-linoleic oil, the predominant fatty acid in Salvia sclarea was α-linolenic acid (around 54%). Among tocols, the main isomers in both seeds and oils were γ-tocopherol, followed by α-tocopherol. Concerning carotenoids, their concentration was around 0.75 mg/100 g of seeds and 0.16 mg/100 g of oils, with a predominance of lutein. Oil and seeds of S. officinalis exhibited higher antioxidant potential compared to S. sclarea investigated samples which could be attributed to higher content of total vitamin E and carotenoids. This study provides results that enables use of two Salvia species as new alternative sources of vegetable oils.


Assuntos
Antioxidantes/química , Óleos Voláteis/química , Salvia/metabolismo , Antioxidantes/análise , Carotenoides/análise , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/análise , Salvia/química , Salvia officinalis/química , Salvia officinalis/metabolismo , Sementes/química , Sementes/metabolismo , alfa-Tocoferol/análise
8.
Crit Rev Food Sci Nutr ; 56(11): 1868-79, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-25675359

RESUMO

The present review is based mainly on papers published between 2000 and 2011 and gives information about the properties of the carotenoid lycopene in chemical and biological systems and its possible role in preventing cardiovascular diseases (CVD). The main aim of this report is to highlight its role as an antioxidant, also reported are bioactive properties that may influence the development of foam cells and protection against endothelial cell damage. The paper will also examine recent observations that lycopene may improve blood flow and reduce inflammatory responses. Lycopene possesses antioxidant properties in vitro, and some epidemiological studies have reported protective effects against the progression of CVD. The oxidation of human low density lipoproteins (LDL) is a fundamental mechanism in the initiation of atherosclerosis. A beneficial role of lycopene as antioxidant in the prevention of CVD is suggested but the data are still controversial. Lycopene is believed to be the most potent carotenoid antioxidant in vitro. Tissue culture experiments and animal studies support potential cardioprotective effects for lycopene and other carotenoids in the blood. Most studies showed beneficial effects of lycopene to individuals who are antioxidant-deficient like elderly patients, or humans exposed to higher levels of oxidative stress like smokers, diabetics, hemodialysis patients and acute myocardial infarction patients. By defining the right population and combining antioxidant potentials of lycopene with vitamins and other bioactive plant compounds, the beneficial role of lycopene in CVD can be clarified in future studies.


Assuntos
Antioxidantes/farmacologia , Doenças Cardiovasculares/prevenção & controle , Carotenoides/farmacologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Humanos , Licopeno , Estresse Oxidativo/efeitos dos fármacos , Ensaios Clínicos Controlados Aleatórios como Assunto , Espécies Reativas de Oxigênio/metabolismo , Fatores de Risco , Triglicerídeos/sangue
9.
Antioxidants (Basel) ; 13(6)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38929150

RESUMO

Jeriva (Syagrus romanzoffiana) is a fruit from palm trees of the Arecaceae family, widely distributed in tropical and subtropical areas of Latin America. It has low production costs and high productivity throughout the year; however, its consumption is very low, and the production goes almost entirely to feed animals or to waste. To improve its consumption, a good characterization of the whole fruit is necessary. The objective of this work was to evaluate the jeriva pulp, peel and seeds according to carotenoids, phenolic compounds, vitamin C, tocopherols and antioxidant potential using HPLC, microplate readers and spectrophotometric methods. Every part of the fruit exhibited antioxidant capacity in the ORAC and TEAC tests, which can be attributed to its high concentration of polyphenols. Carotenoids were more present in the pulp and peel and almost absent in the seeds. Vitamin C ranged from 12 ± 1 for the seeds up to 92 ± 3 mg/100 g for the pulp. The total phenolic content was quantified between 473 ± 39 for the seeds and 1089 ± 32 mg of gallic acid equivalents (GAEs)/100 g for the pulp. These results demonstrate that all parts of this fruit have important bioactive nutrients, with promising perspectives for further scientific approaches and for composing formulations of food products to enhance functional properties.

10.
Nutr Metab (Lond) ; 20(1): 34, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582723

RESUMO

In the last century, vitamin A was identified that included the nutritional relevant vitamin A1 / provitamin A1, as well as the vitamin A2 pathway concept. Globally, nutritional guidelines have focused on vitamin A1 with simplified recommendations and calculations based solely on vitamin A. The vitamin A / provitamin A terminology described vitamin A with respect to acting as a precursor of 11-cis-retinal, the chromophore of the visual pigment, as well as retinoic acid(s), being ligand(s) of the nuclear hormone receptors retinoic acid receptors (RARs) α, ß and γ. All-trans-retinoic acid was conclusively shown to be the endogenous RAR ligand, while the concept of its isomer 9-cis-retinoic acid, being "the" endogenous ligand of the retinoid-X receptors (RXRs), remained inconclusive. Recently, 9-cis-13,14-dihydroretinoic acid was conclusively reported as an endogenous RXR ligand, and a direct nutritional precursor was postulated in 2018 and further confirmed by Rühl, Krezel and de Lera in 2021. This was further termed vitamin A5/X / provitamin A5/X. In this review, a new vitamin A5/X / provitamin A5/X concept is conceptualized in parallel to the vitamin A(1) / provitamin A(1) concept for daily dietary intake and towards dietary guidelines, with a focus on the existing national and international regulations for the physiological and nutritional relevance of vitamin A5/X. The aim of this review is to summarize available evidence and to emphasize gaps of knowledge regarding vitamin A5/X, based on new and older studies and proposed future directions as well as to stimulate and propose adapted nutritional regulations.

11.
Food Chem ; 382: 131854, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35248403

RESUMO

In organic table egg production, saponified extracts of carotenoids are not allowed to intensify egg yolk colour. Therefore, we investigated the suitability of organically produced marigold flower meal (Tagetes erectus, TE) and spinach (Spinacia oleracea, SO) as carotenoid sources (mixture of 25% TE and 75% SO) to reach values of 9-10 'Roche Yolk Colour Fan' units (RYCF units). Feeding a completely unsupplemented control diet resulted in a yolk colour of 4.7 RYCF units, a total supply of 11.1 g/kg, 14.6 g/kg and 17.5 g/kg of TE and SO as stand-alone carotenoid sources induced a significant increase to 8.0, 8.2 and 8.9 RYCF units. Under 'winter-feeding conditions', i.e. minimal carotenoid supply in the diet, 17.5 g/kg TE and SO resulted in 9.3 ± 0.7 RYCF units. It can be concluded that supplementing TE and SO is suitable to improve the yolk colour in organically produced table eggs.


Assuntos
Ração Animal , Gema de Ovo , Ração Animal/análise , Animais , Galinhas , Cor , Dieta , Fazendeiros , Humanos
12.
Z Naturforsch C J Biosci ; 77(7-8): 331-342, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35231163

RESUMO

Matricaria aurea (Loefl.) Schultz Bip. (Asteraceae), known as golden chamomile, has been traditionally used for the treatment of various diseases. In this study, total phenolic, flavonoid, and tannin contents of total extract and different fractions of this plant were determined. The antioxidant, cytotoxic, and antimicrobial activities were also evaluated. Moreover, the phenolic profiles of selected fractions were determined by HPLC and LC-MS/MS analysis. Results demonstrated total phenolic contents of 37.8-57.2 mg GAE/g and total flavonoid contents of 3.0-111.2 mg QE/g. The ethyl acetate and methanol fractions (EF and MF) had the highest concentrations of phenolic, tannin, and flavonoid compounds. In both DPPH radical scavenging assay and phosphomolybdenum reduction assay, EF showed the best antioxidant activity, followed by MF. EF and MF indicated also the best antibacterial activities against Bacillus subtilis (MIC 1.56 and 12.5 mg ml-1) and Staphylococcus aureus (MIC 0.78 and 12.5 mg ml-1). Hexane fraction (HF) had no antibacterial effect. None of the samples had antifungal effect. MTT (3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay revealed for EF and HF the highest antiproliferative activities (IC50 values ranged from 111.8 to 294.6 µg ml-1). The presence of chlorogenic acid, ferulic acid, and luteolin-7-O-glucoside in MF, and p-coumaric acid in EF was confirmed and quantified.


Assuntos
Antineoplásicos , Matricaria , Antibacterianos/farmacologia , Antifúngicos , Antioxidantes/química , Camomila , Cromatografia Líquida , Flavonoides/análise , Flavonoides/farmacologia , Fenóis/análise , Fenóis/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem , Taninos
13.
Br J Nutr ; 105(2): 263-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20735877

RESUMO

Epidemiological studies suggest that consumption of tomato products reduces the risk of CVD via antioxidant, hypocholesterolaemic and anti-inflammatory mechanisms. Although experimental data also describe beneficial effects on endothelial function, clinical data in human subjects are lacking. To test the hypothesis that tomato ingestion ameliorates endothelial function, we randomised healthy non-smoking postmenopausal women to consume a buttered roll with and without tomato purée (70 g) in a cross-over design. Endothelial-dependent flow-mediated dilation (FMD) and endothelial-independent nitro-mediated dilation of the brachial artery were assessed with high-resolution ultrasound (13 MHz linear array transducer). Acute (24 h) and long-term (7 d) effects were examined after daily consumption of the described meal. Nineteen volunteers completed the protocol and provided technically suitable ultrasound measurement data. Plasma lycopene levels increased from 0·30 (sem 0·04) (baseline) to 0·42 (sem 0·04) and to 0·74 (sem 0·06) µm after 24 h and 7 d, respectively, with tomato purée consumption. These data indicated an effective absorption of the tomato product. However, both acute and long-term tomato purée consumption had no effects on endothelium-dependent or -independent dilation of the brachial artery. In addition, we found no correlation between lycopene plasma levels and FMD. In conclusion, consumption of tomato products associated with a significant increase in plasma lycopene levels had no effects on endothelial function in healthy postmenopausal women.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta , Endotélio Vascular/fisiologia , Solanum lycopersicum , Idoso , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiologia , Doenças Cardiovasculares/fisiopatologia , Carotenoides/sangue , Estudos Cross-Over , Endotélio Vascular/diagnóstico por imagem , Feminino , Humanos , Licopeno , Menopausa , Pessoa de Meia-Idade , Ultrassonografia , Vasodilatação/fisiologia
14.
Antioxidants (Basel) ; 10(11)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34829561

RESUMO

High pressure processing (HPP) represents a non-thermal preservation technique for the gentle treatment of food products. Information about the impact of HPP on lipophilic food ingredients (e.g., carotenoids, vitamin E) is still limited in more complex matrices such as kale. Both the variation of pressure levels (200-600 MPa) and different holding times (5-40 min) served as HPP parameters. Whereas a slightly decreasing solvent extractability mostly correlated with increasing pressure regimes; the extension of holding times resulted in elevated extract concentrations, particularly at high-pressures up to 600 MPa. Surprisingly, slightly increasing bioaccessibility correlated with both elevated pressures and extended holding times, indicating matrix-dependent processes during in vitro digestion, compared to results of extractability. Moreover, the verification of syringe filters for digest filtration resulted in the highest relative recoveries using cellulose acetate and polyvinylidene difluoride membranes. The α-tocopherol equivalent antioxidant capacity (αTEAC) and oxygen radical antioxidant capacity (ORAC) assays of treated kale samples, chopped larger in size, showed increased antioxidant capacities, regarding elevated pressures and extended holding times. Consequently, one may conclude that HPP was confirmed as a gentle treatment technique for lipophilic micronutrients in kale. Nevertheless, it was indicated that sample pre-treatments could affect HP-related processes in food matrices prior to and possibly after HPP.

15.
Annu Rev Food Sci Technol ; 12: 433-460, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33467905

RESUMO

Carotenoids are versatile isoprenoids that are important in food quality and health promotion. There is a need to establish recommended dietary intakes/nutritional reference values for carotenoids. Research on carotenoids in agro-food and health is being propelled by the two multidisciplinary international networks, the Ibero-American Network for the Study of Carotenoids as Functional Foods Ingredients (IBERCAROT; http://www.cyted.org) and the European Network to Advance Carotenoid Research and Applications in Agro-Food and Health (EUROCAROTEN; http://www.eurocaroten.eu). In this review, considerations for their safe and sustainable use in products mostly intended for health promotion are provided. Specifically, information about sources, intakes, and factors affecting bioavailability is summarized. Furthermore, their health-promoting actions and importance in public health in relation to the contribution of reducing the risk of diverse ailments are synthesized. Definitions and regulatory and safety information for carotenoid-containing products are provided. Lastly, recent trends in research in the context of sustainable healthy diets are summarized.


Assuntos
Carotenoides , Alimento Funcional , Mudança Climática , Suplementos Nutricionais , Alimento Funcional/análise
16.
Nutr Rev ; 79(5): 544-573, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32766681

RESUMO

There is uncertainty regarding carotenoid intake recommendations, because positive and negative health effects have been found or are correlated with carotenoid intake and tissue levels (including blood, adipose tissue, and the macula), depending on the type of study (epidemiological vs intervention), the dose (physiological vs supraphysiological) and the matrix (foods vs supplements, isolated or used in combination). All these factors, combined with interindividual response variations (eg, depending on age, sex, disease state, genetic makeup), make the relationship between carotenoid intake and their blood/tissue concentrations often unclear and highly variable. Although blood total carotenoid concentrations <1000 nmol/L have been related to increased chronic disease risk, no dietary reference intakes (DRIs) exist. Although high total plasma/serum carotenoid concentrations of up to 7500 nmol/L are achievable after supplementation, a plateauing effect for higher doses and prolonged intake is apparent. In this review and position paper, the current knowledge on carotenoids in serum/plasma and tissues and their relationship to dietary intake and health status is summarized with the aim of proposing suggestions for a "normal," safe, and desirable range of concentrations that presumably are beneficial for health. Existing recommendations are likewise evaluated and practical dietary suggestions are included.


Assuntos
Carotenoides/administração & dosagem , Ingestão de Alimentos , Carotenoides/análise , Carotenoides/sangue , Dieta , Feminino , Humanos , Licopeno , Masculino , Recomendações Nutricionais , beta Caroteno
17.
Antioxidants (Basel) ; 8(11)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671718

RESUMO

Carotenoids are a group of natural pigments, consisting of more than 750 compounds known so far [...].

18.
Nutrition ; 58: 30-35, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30278427

RESUMO

OBJECTIVES: More than 70% of birch pollen-allergic individuals are affected by a cross-allergy from apples. The aim of this study was to determine if an increased polyphenolic content of apples is inversely related to clinical allergic reactions in sufferers. METHODS: The polyphenolic content of two old and two new apple cultivars was analyzed using high performance liquid chromatography. The in vitro concentration of sulfidoleukotrienes and the CD63 basophil activation of 27 birch pollen sufferers with cross-reactivity to apples were determined with cellular antigen stimulation and basophil activation tests after incubation with different apple cultivars. RESULTS: The flesh of old cultivars was characterized by significantly higher total polyphenolic content (86.1 ± 5.5 µg/g) than that of new cultivars (24.7 ± 7.2 µg/g). The concentration of sulfidoleukotrienes and the CD63 basophil activation of old apple cultivars was up to 62% lower than new ones and decreased as the degree of enzymatic browning increased. CONCLUSION: Old apples cultivars are better tolerated than new ones by birch pollen-allergic individuals. The in vitro allergenicity (activation of effector cells) of apples depends on the total polyphenolic content and the degree of enzymatic browning.


Assuntos
Alérgenos/imunologia , Hipersensibilidade Alimentar/imunologia , Malus/imunologia , Polifenóis/imunologia , Adulto , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
19.
Mol Nutr Food Res ; 63(5): e1800788, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30512227

RESUMO

SCOPE: Although about 90% of lycopene in dietary sources occurs in the linear all-trans conformation, a large proportion of the lycopene found in human tissues is of the cis-isomer type, notably (5Z)-lycopene. The biological effects of this (5Z) isomer have been under-researched. The aim of this study is to evaluate some biological functions of (5Z)-lycopene in adipocytes and to compare them with those of (all-E)-lycopene. METHODS AND RESULTS: (all-E)- and (5Z)-Lycopene displayed strong similarities in global gene expression profile and biological pathways impacted. Peroxisome proliferator-activated receptor (PPAR) signaling is identified as a major actor mediating the effects of lycopene isomers. Transactivation assays confirmed the ability of both isomers to transactivate PPARγ. In addition, the TNFα-induced proinflammatory cytokine mRNA expression in 3T3-L1 adipocytes is reduced by both isomers via a reduction in the phosphorylation levels of p65. Finally, lycopene isomers restore the TNF-α-blunted uptake of glucose by adipocytes via a modulation of AKT phosphorylation. CONCLUSION: These results show that lycopene isomers exert similar biological functions in adipocytes, linked to their ability to transactivate PPARγ. These findings add to our knowledge of lycopene effects in adipocyte biology and point to the possible use of lycopene in the prevention of obesity-related disorders.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Licopeno/química , Licopeno/farmacologia , Células 3T3-L1 , Animais , Citocinas/metabolismo , Desoxiglucose/farmacocinética , Regulação da Expressão Gênica/efeitos dos fármacos , Isomerismo , Camundongos , NF-kappa B/metabolismo , PPAR gama/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo
20.
J Am Chem Soc ; 130(19): 6288-97, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-18402448

RESUMO

The surface complex [([triple bond]SiO)Re([triple bond]CtBu)(=CHtBu)(CH2tBu)] (1) is a highly efficient propene metathesis catalyst with high initial activities and a good productivity. However, it undergoes a fast deactivation process with time on stream, which is first order in active sites and ethene. Noteworthy, 1-butene and pentenes, unexpected products in the metathesis of propene, are formed as primary products, in large amount relative to Re (>>1 equiv/Re), showing that their formation is not associated with the formation of inactive species. DFT calculations on molecular model systems show that byproduct formation and deactivation start by a beta-H transfer trans to the weak sigma-donor ligand (siloxy) at the metallacyclobutane intermediate having a square-based pyramid geometry. This key step has an energy barrier slightly higher than that calculated for olefin metathesis. After beta-H transfer, the most accessible pathway is the insertion of ethene in the Re-H bond. The resulting pentacoordinated trisperhydrocarbyl complex rearranges via either (1) alpha-H abstraction yielding the unexpected 1-butene byproduct and the regeneration of the catalyst or (2) beta-H abstraction leading to degrafting. These deactivation and byproduct formation pathways are in full agreement with the experimental data.


Assuntos
Alcenos/química , Alcinos/química , Ciclobutanos/química , Compostos Organometálicos/química , Rênio/química , Dióxido de Silício/química , Catálise , Ciclopentanos/química , Hidrogênio/química , Isomerismo , Cinética , Espectroscopia de Ressonância Magnética , Modelos Químicos , Oxirredução , Espectrofotometria Infravermelho , Termodinâmica
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