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1.
Nutr Bull ; 45(4): 362-373, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33380903

RESUMO

Wheat is the major staple food in Western Europe and an important source of energy, protein, dietary fibre, minerals, B vitamins and phytochemicals. Plant breeders have been immensely successful in increasing yields to feed the growing global population. However, concerns have been expressed that the focus on increasing yield and processing quality has resulted in reduced contents of components that contribute to human health and increases in adverse reactions. We review the evidence for this, based largely on studies in our own laboratories of sets of wheats bred and grown between the 18th century and modern times. With the exception of decreased contents of mineral micronutrients, there is no clear evidence that intensive breeding has resulted in decreases in beneficial components or increases in proteins which trigger adverse responses. In fact, a recent study of historic and modern wheats from the UK showed increases in the contents of dietary fibre components and a decreased content of asparagine in white flour, indicating increased benefits for health.

2.
J Intern Med ; 288(5): 560-569, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32415867

RESUMO

BACKGROUND: We have earlier reported that amiodarone, a potent and commonly used antiarrhythmic drug increases serum desmosterol, the last precursor of cholesterol, in 20 cardiac patients by an unknown mechanism. OBJECTIVE: Here, we extended our study to a large number of cardiac patients of heterogeneous diagnoses, evaluated the effects of combining amiodarone and statins (inhibitors of cholesterol synthesis at the rate-limiting step of hydroxy-methyl-glutaryl CoA reductase) on desmosterol levels and investigated the mechanism(s) by which amiodarone interferes with the metabolism of desmosterol using in vitro studies. METHODS AND RESULTS: We report in a clinical case-control setting of 236 cardiac patients (126 with and 110 without amiodarone treatment) that amiodarone medication is accompanied by a robust increase in serum desmosterol levels independently of gender, age, body mass index, cardiac and other diseases, and the use of statins. Lipid analyses in patient samples taken before and after initiation of amiodarone therapy showed a systematic increase of desmosterol upon drug administration, strongly arguing for a direct causal link between amiodarone and desmosterol accumulation. Mechanistically, we found that amiodarone resulted in desmosterol accumulation in cultured human cells and that the compound directly inhibited the 24-dehydrocholesterol reductase (DHCR24) enzyme activity. CONCLUSION: These novel findings demonstrate that amiodarone blocks the cholesterol synthesis pathway by inhibiting DHCR24, causing a robust accumulation of cellular desmosterol in cells and in the sera of amiodarone-treated patients. It is conceivable that the antiarrhythmic potential and side effects of amiodarone may in part result from inhibition of the cholesterol synthesis pathway.


Assuntos
Amiodarona/efeitos adversos , Antiarrítmicos/efeitos adversos , Arritmias Cardíacas/sangue , Arritmias Cardíacas/tratamento farmacológico , Colesterol/biossíntese , Desmosterol/sangue , Proteínas do Tecido Nervoso/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Estudos de Casos e Controles , Células Cultivadas , Colesterol/sangue , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade
3.
J Intern Med ; 283(1): 93-101, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28861933

RESUMO

BACKGROUND: Amiodarone is an effective and widely used antiarrhythmic drug with many possible adverse effects including hypercholesterolaemia and hepatotoxicity. OBJECTIVE: Our aim was to evaluate how long-term amiodarone treatment affects cholesterol metabolism. METHODS: The study population consisted of 56 cardiac patients, of whom 20 were on amiodarone (amiodarone + group) and 36 did not use the drug (amiodarone - group). We also studied a control group of 124 individuals selected randomly from the population. Cholesterol metabolism was evaluated by analysis of serum noncholesterol sterols by gas-liquid chromatography and gas chromatography-mass spectrometry. RESULTS: Comparisons of serum lipids and noncholesterol sterols across the three groups showed increased serum triglyceride in users of amiodarone but no statistically significant group differences in total, LDL or HDL cholesterol or serum proprotein convertase subtilisin/kexin type 9 concentrations. Nor did the groups differ in the ratios of cholestanol or plant sterols to cholesterol in serum, suggesting that cholesterol absorption was unaltered. However, all users of amiodarone had very markedly elevated serum desmosterol concentrations: the desmosterol-to-cholesterol ratio (102 × µmol mmol-1 ) averaged 1030.7 ± 115.7 (mean ± SE) in the amiodarone + group versus 82.7 ± 3.4 and 75.9 ± 1.4 in the amiodarone - and the population control groups (P < 0.001), respectively. CONCLUSION: Use of amiodarone was associated with on average 12-fold serum desmosterol concentrations compared with the control groups. This observation is fully novel and suggests that amiodarone interferes with the conversion of desmosterol to cholesterol in the cholesterol synthesis pathway. Whether accumulation of desmosterol plays a role in amiodarone-induced hepatotoxicity deserves to be studied in the future.


Assuntos
Amiodarona/efeitos adversos , Cardiomiopatias , Desmosterol/sangue , Miocardite , Sarcoidose , Taquicardia Ventricular/tratamento farmacológico , Amiodarona/administração & dosagem , Amiodarona/farmacocinética , Antiarrítmicos/administração & dosagem , Antiarrítmicos/efeitos adversos , Antiarrítmicos/farmacocinética , Biópsia/métodos , Técnicas de Imagem Cardíaca/métodos , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/diagnóstico , Cardiomiopatias/patologia , Colesterol/metabolismo , Eletrocardiografia/métodos , Feminino , Finlândia , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/induzido quimicamente , Miocardite/diagnóstico , Miocardite/patologia , Sarcoidose/diagnóstico , Sarcoidose/etiologia , Sarcoidose/patologia
4.
J Anim Sci ; 93(9): 4408-23, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26440341

RESUMO

Forage type and management influences the nutritional quality and fatty acid composition of ruminant milk. Replacing grass silage with red clover (RC; L.) silage increases milk fat 18:3-3 concentration. Red clover has a higher polyphenol oxidase (PPO) activity compared with grasses, which has been suggested to decrease lipolysis and . The present study characterized the abundance and fatty acid composition of esterified lipid and NEFA before and after ensiling of grass and RC to investigate the influence of forage species, growth stage, and extent of fermentation on lipolysis. A randomized block design with a 2 × 3 × 4 factorial arrangement of treatments was used. Treatments comprised RC or a mixture of timothy ( L.) and meadow fescue ( Huds.) harvested at 3 growth stages and treated with 4 levels of formic acid (0, 2, 4, and 6 L/t). Lipid in silages treated with 0 or 6 L/t formic acid were extracted and separated into 4 fractions by TLC. Total PPO activity in fresh herbage and the content of soluble bound phenols in all silages were determined. Concentrations of 18:3-3 and total fatty acids (TFA) were higher ( < 0.001) for RC than for grass. For both forage species, 18:3-3 and TFA content decreased linearly ( < 0.001) with advancing growth stage, with the highest abundance at the vegetative stage. Most of lipid in fresh RC and grass herbage (97%) was esterified, whereas NEFA accounted for 71% of TFA in both silages. Ensiling resulted in marginal increases in TFA content and the amounts of individual fatty acids compared with fresh herbages. Herbage total PPO activity was higher ( < 0.001) for RC than grass (11 vs. 0.11 µkatal/g leaf fresh weight). Net lipolysis during ensiling was extensive for both forage species (660 to 759 g/kg fatty acid for grass and 563 to 737 g/kg fatty acid for RC). Formic acid application (0 vs. 6 L/t) resulted in a marked decrease ( = 0.026) in net lipolysis during the ensiling of RC, whereas the opposite was true ( = 0.026) for grass. In conclusion, results suggest that formic acid addition during the ensilage of RC decreases lipolysis . For both plant species, total PPO activity was not associated with the extent of lipolysis . However, bound phenols formed via PPO activity appear to have a role in protecting lipid and protein against degradation in grass and lowering proteolysis of RC during ensiling.


Assuntos
Ácidos Graxos/química , Lipídeos/química , Lipólise , Poaceae/metabolismo , Silagem/análise , Trifolium/metabolismo , Animais , Peso Corporal , Fermentação , Análise de Alimentos , Formiatos/química
5.
J Dairy Sci ; 94(9): 4413-30, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21854915

RESUMO

Five multiparous Finnish Ayrshire cows fed red clover silage-based diets were used in a 5 × 5 Latin square with 21-d experimental periods to evaluate the effects of various plant oils or camelina expeller on animal performance and milk fatty acid composition. Treatments consisted of 5 concentrate supplements containing no additional lipid (control), or 29 g/kg of lipid from rapeseed oil (RO), sunflower-seed oil (SFO), camelina-seed oil (CO), or camelina expeller (CE). Cows were offered red clover silage ad libitum and 12kg/d of experimental concentrates. Treatments had no effect on silage or total dry matter intake, whole-tract digestibility coefficients, milk yield, or milk composition. Plant oils in the diet decreased short- and medium-chain saturated fatty acid (6:0-16:0) concentrations, including odd- and branched-chain fatty acids and enhanced milk fat 18:0 and 18-carbon unsaturated fatty acid content. Increases in the relative proportions of cis 18:1, trans 18:1, nonconjugated 18:2, conjugated linoleic acid (CLA), and polyunsaturated fatty acids in milk fat were dependent on the fatty acid composition of oils in the diet. Rapeseed oil in the diet was associated with the enrichment of trans 18:1 (Δ4, 6, 7, 8, and 9), cis-9 18:1, and trans-7,cis-9 CLA, SFO resulted in the highest concentrations of trans-5, trans-10, and trans-11 18:1, Δ9,11 CLA, Δ10,12 CLA, and 18:2n-6, whereas CO enhanced trans-13-16 18:1, Δ11,15 18:2, Δ12,15 18:2, cis-9,trans-13 18:2, Δ11,13 CLA, Δ12,14 CLA, Δ13,15 CLA, Δ9,11,15 18:3, and 18:3n-3. Relative to CO, CE resulted in lower 18:0 and cis-9 18:1 concentrations and higher proportions of trans-10 18:1, trans-11 18:1, cis-9,trans-11 CLA, cis-9,trans-13 18:2, and trans-11,cis-15 18:2. Comparison of milk fat composition responses to CO and CE suggest that the biohydrogenation of unsaturated 18-carbon fatty acids to 18:0 in the rumen was less complete for camelina lipid supplied as an expeller than as free oil. In conclusion, moderate amounts of plant oils in diets based on red clover silage had no adverse effects on silage dry matter intake, nutrient digestion, or milk production, but altered milk fat composition, with changes characterized as a decrease in saturated fatty acids, an increase in trans fatty acids, and enrichment of specific unsaturated fatty acids depending on the fatty acid composition of lipid supplements.


Assuntos
Ácidos Graxos/análise , Leite/química , Óleos de Plantas/farmacologia , Silagem , Trifolium , Animais , Brassicaceae , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Ácidos Graxos Monoinsaturados , Feminino , Lactação/efeitos dos fármacos , Óleo de Brassica napus , Silagem/análise , Óleo de Girassol
6.
Toxicol In Vitro ; 23(5): 755-62, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19328846

RESUMO

While health implications caused by cholesterol oxidation products (COPs) seem to be generally accepted, research on phytosterol oxidation products (POPs) is still limited. Since POPs are commercially not available knowledge on their toxic activities is mainly derived from blends instead of pure compounds. Therefore the aim of the present study was to examine the cytotoxicity of three individual oxidation products of beta-sitosterol, 7-ketositosterol, 7beta-OH-sitosterol, 7alpha-OH-sitosterol, a mixture of 6beta-OH-3-keto-sitosterol/6alpha-OH-3-keto-sitosterol (ratio 4:3) and a mixture of polar oxides towards HepG2-cells. All tested compounds were found to reduce cell viability in a significant and concentration dependent way, particularly 7-keto- and 7alpha-OH-sitosterol showed to be highly active. Only for 7-ketositosterol an increase in early apoptotic cells was observed. Enhancement of O(2)(-) production was assessed for all oxides, whereas malondialdehyd (MDA) levels were increased by 7-keto- and 7alpha-OH-sitosterol only. However, cell death did not appear to be necessarily dependent on the generation of oxidative stress. Further no DNA strand breaks were observed with the COMET assay. By assessing the accumulation of single oxidation products in the cells a link between higher proportions of oxides inside the cells and their cytotoxic potential could be found.


Assuntos
Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Óxidos/toxicidade , Sitosteroides/toxicidade , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Ensaio Cometa , Quebras de DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Neoplasias Hepáticas/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Óxidos/administração & dosagem , Óxidos/química , Sitosteroides/química
7.
Eur J Clin Nutr ; 59(1): 123-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15340369

RESUMO

OBJECTIVE: To assess the effects of maternal dietary and supplement intake of vitamins C and E on breast milk antioxidant composition (vitamin C, alpha-tocopherol and beta-carotene) and their protective potential against the development of atopy in the infant. DESIGN, SUBJECTS AND METHODS: Mothers with atopic disease were recruited at the end of gestation and maternal sensitization was assessed by skin-prick testing. The 4-day food records of the mothers and breast milk samples were collected at the infants' age of 1 month. Infants' atopy was defined by the presence of atopic dermatitis during the first year of life and a positive skin-prick test reaction at 12 months of age (n=34). RESULTS: Maternal intake of vitamin C in diet but not as supplement was shown to determine the concentration of vitamin C in breast milk. A higher concentration of vitamin C in breast milk was associated with a reduced risk of atopy in the infant (OR=0.30; 95% CI 0.09-0.94; P=0.038), whereas alpha-tocopherol had no consistent relationship with atopy. The group at risk of suboptimal vitamin C supply from breast milk was identified as infants whose mothers suffer from food hypersensitivity. CONCLUSION: A maternal diet rich in natural sources of vitamin C during breastfeeding could reduce the risk of atopy in high-risk infants.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Dermatite Atópica/epidemiologia , Fenômenos Fisiológicos da Nutrição do Lactente , Fenômenos Fisiológicos da Nutrição Materna , Leite Humano/imunologia , Vitamina E/administração & dosagem , Adulto , Antioxidantes/análise , Ácido Ascórbico/análise , Ácido Ascórbico/imunologia , Aleitamento Materno , Intervalos de Confiança , Dermatite Atópica/imunologia , Suplementos Nutricionais , Feminino , Humanos , Lactente , Alimentos Infantis , Recém-Nascido , Leite Humano/química , Razão de Chances , Gravidez , Fatores de Risco , Testes Cutâneos , Vitamina E/análise , Vitamina E/imunologia
8.
Br J Nutr ; 92(4): 671-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15522137

RESUMO

The Finnish national food composition database Fineli was updated with recent analytical values for plant sterols (PS) (sitosterol, campesterol, stigmasterol, avenasterol, brassicasterols and stanols) and cholesterol. The quality of the new analytical data was assessed. The aims of the present study were: (1) to compare the effect of old and new database values on PS and cholesterol intakes based on average per capita food consumption data; (2) to estimate the current intake and major sources of these compounds in various population groups according to the national FINDIET 1997 survey data. The intake of total PS was 305 mg/d for men and 237 mg/d for women. The respective intakes for cholesterol were 284 mg/d and 201 mg/d. Women had a higher density of PS in their diets than men, whereas the cholesterol density in the diets did not differ between genders. Cereals, margarine, vegetables and vegetable oils were the main food sources of PS. Meat, meat products and eggs were the main sources of cholesterol. A 9 % greater PS intake estimate was obtained with the new PS database compared with the old PS database, probably due to minor methodological differences between the new and old analyses. Notable changes in analytical methods suggest a lower value (-19 %) for cholesterol intake calculated from the new database compared with the old one. We conclude that researchers can have confidence in the new values for PS and cholesterol, because systematic evaluation of the new analytical values showed them to be of high quality.


Assuntos
Colesterol na Dieta/administração & dosagem , Fitosteróis/administração & dosagem , Adulto , Colesterol na Dieta/análise , Bases de Dados Factuais , Dieta , Inquéritos sobre Dietas , Escolaridade , Feminino , Finlândia , Análise de Alimentos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Fitosteróis/análise , Fatores Sexuais
9.
J Chromatogr A ; 881(1-2): 217-27, 2000 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-10905705

RESUMO

Natural vitamin E is composed of eight different vitamers (alpha-, beta-, gamma- and delta-tocopherols and alpha-, beta-, gamma- and delta-tocotrienols). As these eight vitamers have different antioxidant and biological activities, it is necessary to have quantitative data on each substance separately. The aim of this study was to find universal HPLC columns for the separation of all eight components and to test if a few columns of the same material (different batches) will give reproducible results. Normal-phase HPLC separations of vitamin E compounds in a prepared mixture (containing oat extracts, palm oil and tocopherol standards) were tried on six silica, three amino and one diol columns. As shown by calculations of retention factors (k), separation factors (alpha), numbers of theoretical plates (N) and resolutions (Rs), the best separations were obtained on three silica columns and two amino columns using 4 or 5% dioxane in hexane as the mobile phase as well as on a diol column using 4% tert.-butyl methyl ether in hexane as the mobile phase.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Vitamina E/análogos & derivados , Espectrometria de Fluorescência , Vitamina E/isolamento & purificação
10.
Lipids ; 33(11): 1073-7, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9870901

RESUMO

This work shows that fucosterol, delta5-avenasterol, and similar ethylidene-side chain sterols can undergo acid-catalyzed isomerization to give a mixture of five isomers. Four isomers formed from fucosterol were analyzed, using gas chromatography-mass spectrometry, and were characterized as delta5-avenasterol, two delta5,23-stigmastadienols, and delta5,24(25)-stigmastadienol. When the unsaponifiables fraction from oat oil was subjected to acid hydrolysis, the two delta5,23-stigmastadienol isomers and delta5,24(25)-stigmastadienol were detected while fucosterol coeluted with sitosterol. Interisomerization of ethylidene-side chain sterols represents a limitation to the use of the acid hydrolysis method in the determination of sterols in food and other plant materials rich in these sterols, e.g., oat lipids.


Assuntos
Estigmasterol/análogos & derivados , Anticolesterolemiantes/química , Avena/química , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Isomerismo , Sementes/química , Estigmasterol/química
11.
Lipids ; 33(7): 715-22, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9688175

RESUMO

The antioxidant effects of alpha- and gamma-tocopherols were evaluated in a model system based on the autooxidation of purified sunflower oil (p-SFO) triacylglycerols at 55 degrees C for 7 d. Both tocopherols were found to cause more than 90% reduction in peroxide value when present at concentrations >20 ppm. Alpha-tocopherol was a better antioxidant than gamma-tocopherol at concentrations < or =40 ppm but a worse antioxidant at concentrations >200 ppm. Neither alpha- nor gamma-tocopherol showed a prooxidant effect at concentrations as high as 2000 ppm. The amount of tocopherols consumed during the course of oxidation was positively correlated to the initial concentration of tocopherols, and the correlation was stronger for alpha- than for gamma-tocopherol. This correlation suggested that, besides reactions with peroxyl radicals, destruction of tocopherols may be attributed to unknown side reactions. Addition of FeSO4, as a prooxidant, caused a 12% increase in the peroxide value of p-SFO in the absence of tocopherols. When tocopherols were added together with FeSO4, some increase in peroxide value was observed for samples containing 200, 600 or 1000 ppm of alpha- but not gamma-tocopherol. The addition of FeSO4, however, caused an increase in the amount of alpha- and gamma-tocopherols destroyed and led to stronger positive correlations between the amount of tocopherols destroyed during oxidation and initial concentration of tocopherols. No synergistic or antagonistic interaction was observed when alpha- and gamma-tocopherols were added together to autooxidizing p-SFO.


Assuntos
Antioxidantes/farmacologia , Triglicerídeos/metabolismo , Vitamina E/farmacologia , Compostos Ferrosos/metabolismo , Helianthus , Peróxidos Lipídicos/metabolismo , Oxirredução , Óleos de Plantas/metabolismo
12.
Nutr Cancer ; 14(3-4): 247-51, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2084621

RESUMO

The effect of sampling site and proximity of malignant tumor on the relative fatty acid composition of human breast adipose tissue was studied in 10 cases of breast cancer. The four anatomic quadrants of breast did not statistically significantly differ from each other in relation to any of the 30 fatty acids studied. Proximity of the malignant tumor did not affect the relative fatty acid composition of fat when compared with more distant sampling sites. Representative samples of breast adipose tissue for fatty acid composition analysis can be obtained from tissue adjacent to the tumor.


Assuntos
Tecido Adiposo/metabolismo , Neoplasias da Mama/metabolismo , Ácidos Graxos/metabolismo , Análise de Variância , Neoplasias da Mama/etiologia , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/metabolismo , Humanos
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