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1.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443479

RESUMO

Cannabis sativa L. has been used for a long time to obtain food, fiber, and as a medicinal and psychoactive plant. Today, the nutraceutical potential of C.sativa is being increasingly reappraised; however, C. sativa roots remain poorly studied, despite citations in the scientific literature. In this direction, we identified and quantified the presence of valuable bioactives (namely, ß-sitosterol, stigmasterol, campesterol, friedelin, and epi-friedelanol) in the root extracts of C. sativa, a finding which might pave the way to the exploitation of the therapeutic potential of all parts of the C. sativa plant. To facilitate root harvesting and processing, aeroponic (AP) and aeroponic-elicited cultures (AEP) were established and compared to soil-cultivated plants (SP). Interestingly, considerably increased plant growth-particularly of the roots-and a significant increase (up to 20-fold in the case of ß-sitosterol) in the total content of the aforementioned roots' bioactive molecules were observed in AP and AEP. In conclusion, aeroponics, an easy, standardized, contaminant-free cultivation technique, facilitates the harvesting/processing of roots along with a greater production of their secondary bioactive metabolites, which could be utilized in the formulation of health-promoting and health-care products.


Assuntos
Cannabis/química , Cannabis/crescimento & desenvolvimento , Hidroponia , Colesterol/análogos & derivados , Colesterol/análise , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/análise , Fitosteróis/análise , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Sitosteroides/análise , Estigmasterol/análise , Triterpenos/análise
2.
Analyst ; 146(15): 4775-4780, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34231558

RESUMO

Cholesterol is an essential compound for human health, and a high or low concentration of cholesterol is closely related to various diseases. Thus, developing a simple method for POCT of cholesterol has great significance in clinical diagnosis. In this work, alginate (Alg) hydrogels with glow-type chemiluminescence (CL) were prepared and applied for rapid and quantitative cholesterol detection via a smartphone. The glow-type CL hydrogels (HRP/COD/luminol/Alg hydrogels) contained luminol as a chemiluminescent reagent, horseradish peroxidase (HRP) and cholesterol oxidase (COD) for enzymatic cascade reactions. The HRP/COD/luminol/Alg hydrogels exhibited outstanding stability, which effectively avoided the enzyme inactivation during long-term storage. Furthermore, the HRP/COD/luminol/Alg hydrogels exhibited longer and more stable glow-type CL. With the help of COD catalytic specificity for cholesterol and bi-enzymatic cascade reactions, the glow-type CL hydrogels realized the specific and sensitive detection of cholesterol. The smartphone was used as a detector instead of a special large instrument for responding to the glow-type CL emission, and a LOD of 7.2 µM was obtained. Therefore, the proposed sensor expands the application of the glow-type CL in POCT and provides an alternative way for cholesterol detection in clinical diagnosis.


Assuntos
Colesterol/análise , Hidrogéis , Testes Imediatos , Peroxidase do Rábano Silvestre , Humanos , Medições Luminescentes , Luminol
3.
Molecules ; 26(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066579

RESUMO

Mass spectrometry imaging is a powerful tool for analyzing the different kinds of molecules in tissue sections, but some substances cannot be measured easily, due to their physicochemical properties. In such cases, chemical derivatization could be applied to introduce the charge into the molecule and facilitate its detection. Here, we study cholesterol derivatization with betaine aldehyde from tissue slices and evaluate how different sample preparation methods influence the signal from the derivatization product. In this study, we have tested different solutions for betaine aldehyde, different approaches to betaine aldehyde deposition (number of layers, deposition nozzle height), and different MALDI matrices for its analysis. As a result, we proved that the proposed approach could be used for the analysis of cholesterol in different tissues.


Assuntos
Betaína/análogos & derivados , Colesterol/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Betaína/química , Encéfalo/metabolismo , Cerebelo/metabolismo , Colesterol/química , Íons , Rim/metabolismo , Limite de Detecção , Fígado/metabolismo , Camundongos
4.
Food Chem ; 353: 129474, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33740509

RESUMO

This study aims to determine toxic compounds polycyclic aromatic hydrocarbons (PAHs) and cholesterol oxidation products (COPs) in thin slices of dried pork as affected by different flavorings and roasting temperature treatments through employing a QuEChERS method coupled with gas chromatograph-tandem mass spectrometer (GC-MS/MS) and gas chromatograph-mass spectrometer (GC-MS), respectively. By employing this method, high accuracy and precision was attained for freeze-dried pork hind leg sample. Following addition of 8 different flavorings with roasting temperature at 120, 160, and 200 °C, the levels of total COPs and PAHs in thin slices of dried pork followed a temperature-dependent increase during roasting, which was further confirmed by principle component analysis. High level of soy sauce or sugar inhibited COP formation, while the low-level minimized PAH formation in thin slices of dried pork during roasting. Sugar was more effective in inhibiting COP formation while soy sauce was more efficient in reducing PAH formation.


Assuntos
Colesterol/análise , Manipulação de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos/análise , Carne de Porco/análise , Animais , Colesterol/química , Dessecação , Limite de Detecção , Oxirredução , Hidrocarbonetos Policíclicos Aromáticos/química , Análise de Componente Principal , Suínos , Espectrometria de Massas em Tandem , Temperatura
5.
Food Chem ; 353: 129418, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33735772

RESUMO

Yolk-based mayonnaise is widely used to enhance the flavor of daily food. In view of health concerns on dietary cholesterol, novel mayonnaises (NMs) were made from Pickering emulsions stabilized by apple pomace particles using micro-jet (MJ-NM), ultrasonic (US-NM), and high-speed-shear homogenizer (HSS-NM), respectively. NMs and commercial mayonnaise (CM) were comparatively investigated in appearance, droplet size, rheological, tribological, and stability properties. NMs presented almost identical appearances to CM except for color. The droplets' size in NMs were larger than CM. Both NMs and CM demonstrated shear-thinning behavior and solid-like properties. Among mayonnaises, MJ-NM was demonstrated the most rapid thixotropy recovery with its storage modulus recovered within 51 s. Although both NMs and CM were of mixed tribology nature, NMs presented lower oral lubricity. Upon 210-day storage, both NMs and CM exhibited excellent stabilities without any oil-water separation occurred. Overall, the Pickering emulsions are promising and health alternatives for traditional mayonnaise.


Assuntos
Colesterol/análise , Condimentos/análise , Emulsões , Malus/química , Tamanho da Partícula
6.
Int J Mol Sci ; 22(3)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525627

RESUMO

Hypercholesterolemia is an independent risk factor of cardiovascular disease, which is among the major causes of death worldwide. The aim of this study was to explore whether Bifidobacterium longum strains exerted intra-species differences in cholesterol-lowering effects in hypercholesterolemic rats and to investigate the potential mechanisms. SD rats underwent gavage with each B. longum strain (CCFM 1077, I3, J3 and B3) daily for 28 days. B. longum CCFM 1077 exerted the most potent cholesterol-lowering effect, followed by B. longum I3 and B3, whereas B. longum B3 had no effect in alleviating hypercholesterolemia. Divergent alleviation of different B. longum strains on hypercholesterolemia can be attributed to the differences in bile salt deconjugation ability and cholesterol assimilation ability in vitro. By 16S rRNA metagenomics analysis, the relative abundance of beneficial genus increased in the B. longum CCFM 1077 treatment group. The expression of key genes involved in cholesterol metabolism were also altered after the B. longum CCFM 1077 treatment. In conclusion, B. longum exhibits strain-specific effects in the alleviation of hypercholesterolemia, mainly due to differences in bacterial characteristics, bile salt deconjugation ability, cholesterol assimilation ability, expressions of key genes involved in cholesterol metabolism and alterations of gut microbiota.


Assuntos
Bactérias/classificação , Bifidobacterium longum/fisiologia , Colesterol/efeitos adversos , Hipercolesterolemia/terapia , Análise de Sequência de DNA/métodos , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Bifidobacterium longum/classificação , Colesterol/análise , DNA Bacteriano/genética , DNA Ribossômico/genética , Modelos Animais de Doenças , Fezes/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Hipercolesterolemia/induzido quimicamente , Hipercolesterolemia/genética , Hipercolesterolemia/microbiologia , Metagenômica , RNA Ribossômico 16S/genética , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie
7.
Poult Sci ; 100(2): 1142-1153, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518073

RESUMO

The objective of this study was to determine and evaluate the impact of the age and housing system on blood indicators (triacylglycerides, total cholesterol, aspartate aminotransferase, total proteins, albumin, glucose) and physical egg quality parameters (egg weight, shape index and surface area, eggshell proportion, thickness, strength, and color, albumen proportion and index, Haugh units, yolk proportion, index and yolk-to-albumen ratio) in selected native breeds of the Czech Republic (the Czech Golden Spotted hens) and Slovakia (the Oravka hens). Furthermore, the concentration of cholesterol in the yolk was determined. A total of 132 animals were used. There were 60 eggs collected from each breed at each monitored period for the evaluation of egg quality. Blood samples were taken by puncture of a wing vein. The assessments were made when the hens were of 34, 42, and 50 weeks old. Enriched cages and floor pens with litter were used as housing systems. The effects of breed, housing system, and age were observed. Furthermore, interactions among these factors were calculated. The significant effect of housing system was found in total cholesterol (P = 0.098) and aspartate aminotransferase (P = 0.0343) and the significant effect of age in total protein (P = 0.0392). The significant effect of breed (P = 0.0199), housing system (P = 0.0001), and age (P = 0.0001) was found in concentration of cholesterol in the yolk. Regarding the egg quality, the significant effect of breed (P = 0.0001) was found in eggshell color, albumen index and Haugh units, whereas the significant effect of housing system was found in egg weight (P = 0.0002), egg surface area (P = 0.0003), eggshell proportion (P = 0.0460), thickness (P = 0.0216), strength (P = 0.0049), and color (P = 0.0009). The significant effect of age was determined in all parameters except for the eggshell proportion and strength. The results represent an interesting comparison of changes in biochemical blood and egg quality parameters. It is necessary to further evaluate these indicators, especially in other genetic resources of hens, where the data are often nonexisting.


Assuntos
Envelhecimento/fisiologia , Galinhas/fisiologia , Ovos/normas , Abrigo para Animais/classificação , Envelhecimento/sangue , Animais , Galinhas/sangue , Colesterol/análise , Colesterol/sangue , República Tcheca , Casca de Ovo , Gema de Ovo/química , Feminino , Óvulo , Soro , Eslováquia
8.
Poult Sci ; 100(2): 1248-1261, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518082

RESUMO

Meat quality attributes vary with chicken age. Understanding the relationship between poultry age and the quality of the meat would be beneficial for efficient poultry farming to meet market needs. The Korat hybrid chicken (KC) is a new crossbred chicken whose meat quality is distinct from that of commercial broiler (CB) chickens and has not been well characterized. In this study, we characterized the physico-chemical properties of KC meat and correlate the findings with Raman spectral data. The protein content of KC breast and thigh meat increased with age. The pH of thigh meat decreased, while the water-holding capacity of breast meat increased as the age of the chickens increased. The amount of cholesterol in breast meat decreased as the rearing period was extended. Inosine 5'-monophosphate and guanosine 5'-monophosphate of breast meat decreased as KC grew older. The shear force values of meat from older birds increased concomitantly with an increase in total collagen. Principle component analysis revealed that the meat quality of CB was greatly different from that of KC meat. High shear force values of KC meat at 20 wk of age were well correlated with an increase in the ß-sheet structure (amide I) and amide III of collagen. Raman spectra at 3,207 cm-1 and relative α-helical content were negatively correlated with shear force values of KC breast meat. These could be used as markers to evaluate KC meat quality.


Assuntos
Galinhas/crescimento & desenvolvimento , Carne/normas , Fatores Etários , Animais , Galinhas/classificação , Colesterol/análise , Colágeno/análise , Ácidos Graxos/análise , Análise de Fourier , Guanosina Monofosfato/análise , Concentração de Íons de Hidrogênio , Inosina Monofosfato/análise , Carne/análise , Proteínas/análise , Purinas/análise , Resistência ao Cisalhamento , Análise Espectral Raman/métodos
9.
Meat Sci ; 176: 108461, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33621830

RESUMO

The current work aimed to investigate the utilization of gelled emulsion (GE) systems stabilized either with cold or hot gelation consisted of peanut and linseed oils as fat replacers in fermented beef sausages. The reformulation provided a healthier lipid profile, that led to decreasing total lipid content, cholesterol, and SFAs (from 46.6% to 23.5%) meanwhile increasing both MUFAs (from 47.3% to 51.0%) and PUFAs (from 4.7% to 25.4%) as well as improving nutritional ratios (ω-6/ω-3, PUFA/SFA, IA, and IT). Cold-set GE caused less significant changes in instrumental color and protected PUFAs compared with hot-set GE, whereas hot-set GE provided advantages over cold-set GE in terms of microstructure, purge loss, and sensory scores. Replacement of beef fat fully by a hot-set GE system instead of using a fat-GE mixture was effective in reducing oxidation. The results demonstrated that utilization of different GE systems can be an effective strategy to contribute to the development of lipid-modified fermented meat products.


Assuntos
Emulsões/química , Lipídeos/análise , Produtos da Carne/análise , Animais , Bovinos , Colesterol/análise , Cor , Ácidos Graxos/análise , Alimentos e Bebidas Fermentados , Óleo de Semente do Linho , Óleo de Amendoim
10.
Ann Lab Med ; 41(4): 366-371, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33536354

RESUMO

Background: Total cholesterol concentration measurement is important in the diagnosis of dyslipidemia and evaluation of cardiovascular disease risk factors. Measurement reliability for obtaining an accurate total cholesterol concentration requires procedure standardization. We evaluated the standardization status for total cholesterol concentration measurement through Korean external quality assessment (EQA) data analysis. Methods: This study involved 1,670 laboratories that participated in the EQA of total cholesterol concentration measurements in 2019 for 32 products from different manufacturers. The target concentrations of three quality control (QC) materials (samples A, B, and C) were measured using the reference method and compared with EQA data. The performance criteria for total cholesterol concentration measurement were based on the National Cholesterol Education Program guidelines, with ±3% inaccuracy. Results: The target values and inaccuracies of the QC material based on the reference method measurements were 254.65±7.64, 108.30±3.25, and 256.29±7.69 mg/dL (6.59±0.20, 2.80±0.08, and 6.63±0.20 mmol/L) for samples A, B, and C, respectively. The performance criteria were not met in 42.7% laboratories for sample A, 68.4% of laboratories for sample B, and 38.0% laboratories for sample C. Conclusions: Despite significant efforts to accurately measure total cholesterol concentrations, further actions are needed for measurement standardization. Manufacturers reporting values that differ from target values should check calibrator traceability; additional efforts to accurately measure total cholesterol concentrations are required for laboratories that use products from these manufacturers.


Assuntos
Colesterol/análise , Humanos , Laboratórios , Padrões de Referência , Reprodutibilidade dos Testes , República da Coreia
11.
Nat Methods ; 18(3): 316-320, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33542509

RESUMO

We report a means by which atomic and molecular secondary ions, including cholesterol and fatty acids, can be sputtered through single-layer graphene to enable secondary ion mass spectrometry (SIMS) imaging of untreated wet cell membranes in solution at subcellular spatial resolution. We can observe the intrinsic molecular distribution of lipids, such as cholesterol, phosphoethanolamine and various fatty acids, in untreated wet cell membranes without any labeling. We show that graphene-covered cells prepared on a wet substrate with a cell culture medium reservoir are alive and that their cellular membranes do not disintegrate during SIMS imaging in an ultra-high-vacuum environment. Ab initio molecular dynamics calculations and ion dose-dependence studies suggest that sputtering through single-layer graphene occurs through a transient hole generated in the graphene layer. Cholesterol imaging shows that methyl-ß-cyclodextrin preferentially extracts cholesterol molecules from the cholesterol-enriched regions in cell membranes.


Assuntos
Membrana Celular/metabolismo , Colesterol/análise , Etanolaminas/análise , Ácidos Graxos/análise , Espectrometria de Massa de Íon Secundário/métodos , Diagnóstico por Imagem , Grafite/química , Simulação de Dinâmica Molecular , Análise de Célula Única/métodos , beta-Ciclodextrinas/química
12.
Poult Sci ; 100(4): 100992, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33610894

RESUMO

This study aimed to evaluate the nutritional value of thigh meat from 4 Polish geese varieties. Protein, fat, and cholesterol content, as well as amino acid and fatty acid profiles, were determined. Based on the percentage of amino acid in protein and fatty acids in meat lipids, the health lipid indices were calculated. The experimental material covered thigh muscles from 17-week-old Kartuska (Ka), Suwalska (Su), Lubelska (Lu), and Kielecka (Ki) geese reared in a semi-intensive system. Muscle protein content did not differ significantly between varieties. The protein content of the Ka, Su, Lu, and Ki goose meat was deemed high-value as it contained all the essential amino acids in the proportions consistent with standard protein values. The muscles of all the researched geese varieties were characterized by a high level of Lys, which indicates that this meat is a good source of it (AASLys 240-280%). Current findings showed that polyunsaturated fatty acids (PUFA)/saturated fatty acids (SFA) and PUFA n-6/n-3 ratios in Ka, Su, Lu, and Ki muscles were found to be within the optimum values for human diets. No significant differences were observed in monounsaturated fatty acids, PUFA, and unsaturated fatty acids (UFA) between the analyzed muscles. The meat of Ka and Su contained significantly more lipids than Lu and Ki. A more beneficial amino acid profile was found in Ka meat due to a higher content of PUFA n-3 and the best n-6/n-3 ratio in comparison with other varieties. The muscles of the Ka variety also contained the least cholesterol. However, the Ki goose muscles stood out among other varieties with the least percentage of SFA, the highest share of docosahexaenoic acid (C 22:6 n-3), as well as the most beneficial value of the following indices: UFA/SFA, hypocholesterolemic fatty acid/hypercholesterolemic fatty acid ratio, and nutritive value index. The thigh muscles of Ka, Su, Lu, and Ki were characterized by an atherogenicity index that met the levels of recommended values (<1) in the diet of a human being, while the thrombogenicity index was slightly higher than the recommended value (<0.5).


Assuntos
Proteínas na Dieta , Ácidos Graxos , Gansos , Carne , Músculo Esquelético , Coxa da Perna , Aminoácidos/análise , Animais , Galinhas , Colesterol/análise , Proteínas na Dieta/análise , Ácidos Graxos/análise , Gansos/classificação , Gansos/fisiologia , Carne/análise , Músculo Esquelético/química , Polônia
13.
J Food Sci ; 86(2): 404-410, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33448052

RESUMO

Beta-cyclodextrin (ß-CD) has been shown to successfully lower the cholesterol content of dairy products, such as butter, but the process tends to negatively impact the overall quality and consistency. In this study, ß-sitosterol, which is similar in structure as cholesterol, was reacted with oleic acid to form ß-sitosteryl oleate (BSO), and this was used to improve the consistency of reduced-cholesterol butter. The reaction was catalyzed by sodium bisulfate (2%, w/w) at 140 °C, and the highest degree of esterification (94.3%) was obtained after 9 hr of reaction using a ß-sitosterol-oleic acid molar ratio of 1:5. Ultra-pasteurized cream was then treated with 15% (w/v) ß-CD at 40 °C with stirring (100 rpm), for 30 min. Results indicated a 95.4% reduction in cholesterol content. Finally, the reduced-cholesterol cream was constituted to contain 3, 5, and 10% (w/w) BSO, after which fat was extracted from the three formulations and their melting profiles compared to that of milk fat. The cream containing 3% BSO showed a profile similar to milk fat and was, therefore, used to formulate BSO-incorporated reduced-cholesterol butter (BSOB). Instrumental analyses showed that BSOB was comparable to the control butter with respect to physical properties, such as hardness/firmness and adhesiveness. PRACTICAL APPLICATION: A modified plant sterol, beta-sitosteryl oleate, was incorporated into a reduced-cholesterol butter to improve its physicochemical properties. The reduced-cholesterol butter was comparable to regular butter with respect to its consistency and melting properties and could be made into sticks. In addition to the reduced-cholesterol butter, this product could provide the foundation for new products blending butter and oils to create other low-cholesterol, reduced saturated-fat products, possibly in stick form.


Assuntos
Manteiga/análise , Fenômenos Químicos , Colesterol/análise , Sitosteroides/análise , Animais , Ácidos Graxos/análise , Dureza , Ácido Oleico , Sitosteroides/química , Sulfitos/química
14.
Anal Bioanal Chem ; 413(6): 1521-1532, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33506339

RESUMO

Cholesterol, the principal zoosterol, is a key metabolite linked to several health complications. Studies have shown its potential as a metabolic biomarker for predicting various diseases and determining food origin. However, the existing INEPT (insensitive nuclei enhanced by polarization transfer) 13C position-specific isotope analysis method of cholesterol by NMR was not suitable for very precise analysis of small quantities due to its long acquisition time and therefore is restricted to products rich in cholesterol. In this work, a symmetric and adiabatic heteronuclear single quantum coherence (HSQC) 2D NMR sequence was developed for the high-precision (few permil) analysis of small quantities of cholesterol. Adiabatic pulses were incremented for improving precision and sensitivity. Moreover, several strategies such as the use of non-uniform sampling, linear prediction, and variable recycling time were optimized to reduce the acquisition time. The number of increments and spectral range were also adjusted. The method was developed on a system with a cryogenically cooled probe and was not tested on a room-temperature system. Our new approach allowed analyzing as low as 5 mg of cholesterol in 31 min with a long-term repeatability lower than 2‰ on the 24 non-quaternary carbon atoms of the molecule comparing to 16.2 h for the same quantity using the existing INEPT method. This result makes conceivable the isotope analysis of matrices low in cholesterol. Graphical abstract.


Assuntos
Isótopos de Carbono/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Queijo/análise , Colesterol/análise , Análise de Alimentos/métodos , Ressonância Magnética Nuclear Biomolecular/métodos , Prótons , Algoritmos , Calibragem , Cromatografia Gasosa , Isótopos , Reprodutibilidade dos Testes , Temperatura
15.
Pharmacology ; 106(1-2): 29-36, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32694250

RESUMO

INTRODUCTION: Homeostasis of cholesterol is crucial for cellular function, and dysregulated cholesterol biosynthesis is a metabolic event that can lead to hepatic and cardiovascular abnormalities. OBJECTIVE: The aim of this study was to investigate the effects and mechanisms of domain-associated protein (Daxx) and androgen receptor (AR) on intracellular cholesterol synthesis. METHODS: HepG2 cells were transfected with pCDNA3.1(+)/Daxx plasmid or treated with testosterone propionate to observe the effects of Daxx and AR on intracellular cholesterol levels. Co-immunoprecipitation experiments were performed to identify the interaction between Daxx and AR and to explore the regulatory effects of this interaction on cholesterol synthesis. RESULTS: Our experiments showed that AR promoted cholesterol synthesis and accumulation by activating sterol-regulatory element-binding protein isoform 2. AR-induced cholesterol synthesis was inhibited by Daxx; however, the expression of AR was not affected. Further studies demonstrated the existence of direct binding between Daxx and AR and this interaction was required to suppress AR activity. CONCLUSIONS: The Daxx-mediated antagonism of AR depicts a more complete picture as to how Daxx regulates intracellular cholesterol level and provides a new target for treatment of atherosclerosis.


Assuntos
Colesterol/biossíntese , Proteínas Correpressoras/metabolismo , Chaperonas Moleculares/metabolismo , Receptores Androgênicos/metabolismo , Compostos Azo , Colesterol/análise , Cromatografia Líquida de Alta Pressão , Colorimetria , Células Hep G2 , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Imunoprecipitação , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
16.
Biomed Chromatogr ; 35(4): e5018, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33125786

RESUMO

The HPLC method was developed and validated for assaying alpha-tocopherol and cholesterol in cryopreservation media. Chromatographic separation was performed on an isocratic system, using a C-18 column. The mobile phase was composed of a mixture of methanol:acetonitrile:water 68:28:4 (v/v/v), using a flow rate of 1.5 mL/min and 20 µL injection volume, at a wavelength of 208 nm. The method was validated according to International Conference on Harmonization guidelines. The method proved to be specific, accurate, precise, and linear with correlation coefficients greater than 0.996 over a wide concentration range of both analytes. Vitamin E and cholesterol presented limits of detection of 0.002 mg/mL, 0.026 mg/mL and limits of quantitation of 0.006 mg/mL, 0.086 mg/mL, respectively. This method is simple and rapid, shows high precision and accuracy, and offers the advantage of simultaneous assaying of vitamin E and cholesterol (alone, in cyclodextrins complexes or in liposome loaded) on semen cryopreservation media.


Assuntos
Colesterol/análise , Criopreservação , Soluções para Preservação de Órgãos/química , Preservação do Sêmen , alfa-Tocoferol/análise , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
17.
J Dairy Sci ; 104(2): 1378-1383, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33189282

RESUMO

We investigated the main sterols, phytosterols, and the α- and γ-tocopherol content in donkey milk during the first 2 mo of lactation. Cholesterol was the main sterol in milk (mean ± standard deviation = 0.97 ± 0.443 g/100 g of fat). Lanosterol was the main minor sterol of animal origin, followed by desmosterol (0.003 ± 0.001 and 0.001 ± 0.001 g/100 g of fat, respectively). Of the phytosterols, ß-sitosterol was the main sterol of vegetal origin in donkey milk (0.005 ± 0.002 g/100 g of fat), but lower levels of campesterol, brassicasterol, and stigmasterol were also recorded. Mean levels of α- and γ-tocopherol were 0.01 ± 0.007 and 0.003 ± 0.001 g/100 g of fat, respectively. We observed no significant changes in sterol or tocopherol content during the first 2 mo of lactation. The presence of lanosterol in donkey milk is of particular interest, because lanosterol is a potential drug and has important physiological effects. The presence of phytosterols, which are considered nutraceutical molecules, enhances the nutritional quality of donkey milk fat for consumers.


Assuntos
Equidae , Leite/química , Fitosteróis/análise , Tocoferóis/análise , Animais , Colestadienóis , Colesterol/análogos & derivados , Colesterol/análise , Desmosterol/análise , Feminino , Lactação/metabolismo , Lanosterol/análise , Valor Nutritivo , Saponinas/metabolismo , Sitosteroides , Esteróis
18.
Anal Chem ; 93(3): 1451-1457, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33370093

RESUMO

Investigating the metabolic profiles of solid sample materials with solution nuclear magnetic resonance (NMR) spectroscopy requires the extraction of these metabolites. This is commonly done by using two immiscible solvents such as water and chloroform for extraction. Subsequent solvent removal makes these extraction procedures very time-consuming. To shorten the preparation time of the NMR sample, the following protocol is proposed: the metabolites from a solid or liquid sample are extracted directly in the NMR tube, the NMR tube is centrifuged, and the metabolite profiles in the aqueous and organic phases are determined by using slice-selective proton NMR experiments. This protocol was tested with 11 black teas and 11 green teas, which can be easily distinguished by their metabolic profiles in the aqueous phase. As a test case for liquid samples, 29 milk samples were investigated. The geographical origin of the diaries where the milk was processed could not be determined unequivocally from the metabolic profiles of the hydrophilic metabolites; however, this was easily seen in the lipid profiles. As shown for the different test samples, the extraction protocol in combination with slice-selection NMR experiments is suitable for metabolic investigations. Because samples are rapidly processed, this approach can be used to explore different extraction strategies for metabolite isolation.


Assuntos
Colesterol/metabolismo , Metabolômica , Leite/metabolismo , Ressonância Magnética Nuclear Biomolecular , Chá/metabolismo , Treonina/metabolismo , Animais , Colesterol/análise , Leite/química , Chá/química , Treonina/análise
19.
Food Chem ; 345: 128868, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33352404

RESUMO

Dietary fats may affect blood lipid levels and the development of cardiovascular diseases. Offal, may contribute to food security in marginalised communities and information on the contribution to dietary fat intake is needed to inform dietary guidelines and recommendations and consumers. This study aimed to describe the fatty acid profile, cholesterol content and indexes of lipid quality. The fatty acid profile and cholesterol were determined by gas chromatography coupled with flame ionisation detection (GC-FID). To evaluate lipid quality the indices of atherogenicity (IA) and thrombogenicity (IT) were calculated. Offal products can contribute beneficial fatty acids to the diet, not only in terms of essential fatty acids such as linoleic (C18:2n-6) and alpha linolenic (C18:3n-3) acids, but also the polyunsaturated fatty acids, arachidonic (C20:4n-6) and eicosapentaenoic (C20:5n3) acids. The offal studied in the present work showed a P/S ratio of 0.04-0.12 and the n-6/n-3 ratio varied between 3.9 and 12.5.


Assuntos
Aterosclerose/etiologia , Colesterol/análise , Gorduras na Dieta/análise , Carne Vermelha/efeitos adversos , Carne Vermelha/análise , Ovinos , Trombose/etiologia , Animais , Cromatografia Gasosa , Humanos
20.
Food Chem ; 334: 127612, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32731121

RESUMO

The study objective was to assess the impact of soybean (SO) and linseed oil (LO) added to feed mixture for laying hens upon the quality characteristics of table eggs, their fatty acid (FA) profile and cholesterol level. The material consisted of eggs from hens fed with a mixture without oil and with the addition of LO or SO in a dose of 2.5%. Eggs were subjected to quality assessment. FA profile and cholesterol content in yolks were determined. The results indicate no negative changes in eggs' quality caused by supplementation. An increase was observed in the n3 FA content in egg yolk in experimental groups, as well as all PUFA (polyunsaturated fatty acids) proportions. No negative impact of these oils on the level of cholesterol was noted. As a consequence, the analysed feed additives can be safely applied as an appropriate material in poultry nutrition to enrich eggs with PUFA.


Assuntos
Ração Animal , Galinhas , Ovos/análise , Óleo de Semente do Linho/farmacologia , Óleo de Soja/farmacologia , Animais , Colesterol/análise , Gema de Ovo/química , Ácidos Graxos/análise , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Insaturados/análise , Feminino
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