RESUMEN
OBJECTIVE: Consumption of energy- and nutrient-dense snacks are recommended for older people to maintain adequate nutrition. We evaluated the effects of dairy-based and energy-enriched berry products consumed as snacks on nutritional and functional status among vulnerable older people receiving home care services. DESIGN: Randomised controlled study. SETTING AND PARTICIPANTS: The study sample consisted of 85 home care clients, with mean age of 81.9 (SD 7.1) years in the intervention group (n=50) and 83.7 (SD 8.1) years in the control group (n=35), and 72% women in both groups. INTERVENTION: In the intervention group, the participants consumed both high-protein dairy-based products and energy-enriched berry purées for three months. The snack products provided nearly 300 kcal and 14 g protein per day. MEASUREMENTS: The Mini Nutritional Assessment (MNA), body mass index (BMI), mid-arm muscular area (MAMA) and concentrations of plasma albumin and prealbumin and blood haemoglobin were used to determine nutritional status, and handgrip strength was used to determine functional status at baseline and after the intervention. RESULTS: After adjustment for age and gender, the intervention showed a significant effect on MNA scores (2.1, 95% [CI]: 1.0 to 3.3) (p=0.003), albumin concentration (2.0 g/L, 95% [CI]: 1.1 to 3.2) (p=0.006) and handgrip strength of the right hand in women (2.4 kg, 95% [CI]: 1.2 to 3.3) (p=0.007). The MNA scores improved in the intervention group, while albumin concentration and handgrip strength decreased in the control group. CONCLUSIONS: Regular use of dairy- and energy-enriched berry-based snacks may improve or maintain nutritional and functional status among older people in home care.
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Frutas/química , Estado Nutricional/fisiología , Bocadillos/fisiología , Anciano de 80 o más Años , Femenino , Servicios de Atención de Salud a Domicilio , Humanos , MasculinoRESUMEN
Allium vegetables (onions, leeks, chives) and in particular garlic have been claimed to have health-promoting potential. This study was conducted to get insight into the perspectives for monitoring the intake of garlic by a biomarker approach. Chemically, the biomarker results from exposure to gamma-glutamyl-S-allyl-l-cysteine, which is first hydrolysed by gamma-glutamine-transpeptidase resulting in the formation of S-allyl-l-cysteine. The latter compound is subsequently N-acetylated by N-acetyltransferase into S-allyl-mercapturic acid (ALMA) and excreted into urine. The mercapturic acid was measured in urine using gaschromatography with mass spectrometry. Thus the intake of garlic was determined to check the compliance of garlic intake in a placebo-controlled intervention study. Results indicate that S-allyl-mercapturic acid could be detected in 15 out of 16 urine samples of garlic supplement takers, indicating good compliance. In addition, the intake of garlic was also monitored in a cross-section study of vegans versus controls in Finland, in which no differences in garlic consumption nor in ALMA output were recorded between vegans and controls. These data indicate good possibilities for further studies in the field of biomarkers to investigate the putative chemopreventive effects of garlic and garlic-containing products.
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Acetilcisteína/orina , Ingestión de Alimentos , Ajo , Plantas Medicinales , Antioxidantes/administración & dosificación , Biomarcadores/orina , Estudios de Casos y Controles , Dieta Vegetariana , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Sensibilidad y EspecificidadRESUMEN
Multiple health benefits associated with phenolic compounds have raised the interest in the contents of these plant metabolites in foods. Several phenolic compounds were quantified from berries of Ribes nigrum (black and green currants) and Ribes x pallidum (red and white currants), by using sequential extraction with ethyl acetate and methanol and an optimized reversed-phase HPLC method with diode array detection. The highest contents of anthocyanins (3,011 mg/kg fresh weight, expressed as the aglycon) and flavonol glycosides (100 mg/kg) were found in black currant. The lack of anthocyanins in the colorless (green, white) berries was associated with increased levels of phenolic acids, especially p-coumaric acid (80 mg/kg in green currant vs. 45 mg/kg in black currant) and 4-hydroxybenzoic acid (18 mg/kg in white currant vs. 3 mg/kg in red currant). Previously, proanthocyanidins have not been quantified from berries. This study showed that the contents of extractable (22-41 mg/kg) and nonextractable proanthocyanidins (32-108 mg/kg) are comparable to those of other phenolics, with the exception of anthocyanins in black currant. Our results suggest that anthocyanins dominate in black and red currants, whereas proanthocyanidins and phenolic acids are the predominant phenolic compounds in green and white currants.
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Frutas/química , Fenol/farmacología , Extractos Vegetales/farmacología , Proantocianidinas , Antocianinas/química , Cromatografía Líquida de Alta Presión , Ácidos Cumáricos/química , Flavonoides/química , Hidrólisis , Hidroxibenzoatos/química , Modelos Químicos , Parabenos/química , Fenol/químicaRESUMEN
The amounts of myricetin, quercetin, and kaempferol were analyzed in 16 red and 2 white berry and grape wines after acid hydrolysis using an RP-HPLC method with diode array detection. The red berry wines analyzed were made mainly from black currant, crowberry, and bog whortleberry, i.e., berries rich in flavonols. The red grape wines were made mainly from Cabernet Sauvignon or Merlot grapes in several countries. The white wines studied were gooseberry and white currant wines and Chardonnay and Riesling wines. The amount of myricetin ranged from 3.8 to 22.6 mg L(-1) in red berry wines and from 0 to 14.6 mg L(-1) in red grape wines. The amount of quercetin was from 2.2 to 24.3 mg L(-1) red berry wines and from <1.2 to 19.4 mg L(-1) in red grape wines. Low levels of kaempferol were found in all red berry wines and in 9 red grape wines. The total concentration of these flavonols was from 6 to 46 mg L(-1) (mean 20 mg L(-1)) in red berry wines and from 4 to 31 mg L(-1) (mean 15 mg L(-1)) in red grape wines. Small amounts of quercetin were found in white currant and gooseberry wines, whereas no flavonols were detected in white grape wines. These results demonstrate that the contents of flavonols in red
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Flavonoides/análisis , Quempferoles , Quercetina/análogos & derivados , Quercetina/análisis , Vino/análisis , Cromatografía Líquida de Alta Presión , Finlandia , FrutasRESUMEN
Plants are rich natural sources of antioxidants in addition to other nutrients. Interventions and cross sectional studies on subjects consuming uncooked vegan diet called living food (LF) have been carried out. We have clarified the efficacy of LF in rheumatoid diseases as an example of a health problem where inflammation is one of the main concerns. LF is an uncooked vegan diet and consists of berries, fruits, vegetables and roots, nuts, germinated seeds and sprouts, i.e. rich sources of carotenoids, vitamins C and E. The subjects eating LF showed highly increased levels of beta and alfa carotenes, lycopen and lutein in their sera. Also the increases of vitamin C and vitamin E (adjusted to cholesterol) were statistically significant. As the berry intake was 3-fold compared to controls the intake of polyphenolic compounds like quercetin, myricetin and kaempherol was much higher than in the omnivorous controls. The LF diet is rich in fibre, substrate of lignan production, and the urinary excretion of polyphenols like enterodiol and enterolactone as well as secoisolaricirecinol were much increased in subjects eating LF. The shift of fibromyalgic subjects to LF resulted in a decrease of their joint stiffness and pain as well as an improvement of their self-experienced health. The rheumatoid arthritis patients eating the LF diet also reported similar positive responses and the objective measures supported this finding. The improvement of rheumatoid arthritis was significantly correlated with the day-to-day fluctuation of subjective symptoms. In conclusion the rheumatoid patients subjectively benefited from the vegan diet rich in antioxidants, lactobacilli and fibre, and this was also seen in objective measures.
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Antioxidantes/metabolismo , Artritis Reumatoide/dietoterapia , Dieta Vegetariana , Fibromialgia/dietoterapia , Antioxidantes/análisis , Artritis Reumatoide/fisiopatología , Carotenoides/sangre , Cromatografía Líquida de Alta Presión , Fibras de la Dieta , Ingestión de Alimentos , Femenino , Fibromialgia/fisiopatología , Flavonoides/análisis , Flavonoles , Frutas/química , Humanos , Lactobacillus , Lignanos/análisis , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Verduras/químicaRESUMEN
1. In order to study the potential beneficial effects of a vegan diet, a cross-sectional study was performed and several biomarkers of chemoprevention were measured in a population of female 'living food' eaters ('vegans'; n = 20) vs matched omnivorous controls (n = 20). 2. White blood cells obtained from fresh blood samples were subjected to the single-cell gel-electrophoresis assay. There was no statistically significant difference between the vegans and controls in the parameters 'tail length' and 'tail moment'. However, the 'tail moment' was significantly lower in a subset of the vegans (i.e.in those who did not use any vitamin and/or mineral supplements). 3. Fresh blood samples were exposed in vitro to the mutagen mitomycin C just prior to culturing. After culturing the number of binucleated lymphocytes with micronuclei was scored. There was no difference between the controls and vegans in the incidence of baseline micronuclei, nor in the number of mitomycin C-induced micronuclei. However, a significant correlation (r = -0.64, P < 0.01) between the number of mitomycin C-induced micronuclei and the activity of erythrocyte superoxide dismutase was found in the vegans. The number of baseline micronuclei increased with age in both groups. These findings may be of biological relevance. 4. The content of glutathione-S-transferase-alpha in plasma was not different between the vegans (n = 12) and controls (n = 12). 5. The present data indicate a few differences in biomarkers of chemopreventive potential in strict vegans vs matched omnivorous controls. The significance of these changes as biologically relevant indicators of beneficial effects of vegan diets in humans needs to be determined in studies with a larger number of subjects.
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Antibióticos Antineoplásicos/toxicidad , Dieta Vegetariana , Leucocitos/efectos de los fármacos , Mitomicina/toxicidad , Adulto , Anciano , Envejecimiento/sangre , Células Cultivadas , Quimioprevención , Estudios Transversales , Daño del ADN/efectos de los fármacos , Daño del ADN/genética , ADN de Cadena Simple , Electroforesis , Eritrocitos/efectos de los fármacos , Eritrocitos/enzimología , Femenino , Glutatión Transferasa/sangre , Humanos , Leucocitos/citología , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Persona de Mediana Edad , Superóxido Dismutasa/sangreRESUMEN
OBJECTIVE: Coumarin 7-hydroxylation was investigated in 21 Finnish vegans (20 females, one male) consuming a strict, uncooked vegan diet ("living food diet") and in their matched omnivorous controls, by means of an in vivo coumarin test. METHOD: A capsule containing 5 mg of coumarin (Venalot) was taken after an overnight fast, and urine samples were collected before and 2, 4 and 6 h after the drug administration. The extent and rate of urinary excretion of 7-hydroxycoumarin was determined using HPLC. RESULTS: The total urinary excretion of 7-hydroxycoumarin during 6 h was 58 (range 23-85) and 64 (range 39-92)% of the administred dose in the vegan and control groups. The coumarin index (excretion of 7-hydroxycoumarin during the first 2 h as percentage of total excretion) was 72% in the vegan and 78% in the control groups. A negative correlation was observed between the coumarin index and the consumption of wheatgrass juice by the vegans (r = -0.60, P < 0.01, n = 21). Proportion of slow hydroxylators (excreting 7-hydroxycoumarin after 4 h) was not statistically different between the groups (5/21 in the vegans vs 8/20 in the controls). CONCLUSION: According to the present study, the clearly different dietary patterns and nutrient intakes between the vegans and the omnivores resulted in similar extent and rate of 7-hydroxycoumarin formation, indicating only a minor effect on coumarin hydroxylase (CYP2A6) activity by the plant substances in the uncooked vegan diet.
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Anticoagulantes/farmacocinética , Cumarinas/farmacocinética , Dieta Vegetariana , Adulto , Anciano , Anticoagulantes/orina , Cumarinas/orina , Ingestión de Alimentos , Femenino , Humanos , Hidroxilación , Masculino , Persona de Mediana Edad , Estado NutricionalRESUMEN
Antioxidant status was investigated in 20 Finnish middle-aged female vegans and in one male vegan who were following a strict, uncooked vegan diet ("living food diet"), by means of a dietary survey and biochemical measurements (blood concentrations of vitamins C and E and beta-carotene, and the activities of the zinc/copper-dependent superoxide dismutase and selenium-dependent glutathione peroxidase). Values were compared with those of omnivores matched for sex, age, social status, and residence. Antioxidant supplementation was used by 4 of 20 female vegans and by 11 of 20 control subjects. Based on dietary records, the vegans had significantly higher intakes of beta-carotene, vitamin E, vitamin C, and copper, and a significantly lower intake of selenium than the omnivorous control subjects. The calculated dietary antioxidant intakes by the vegans, expressed as percentages of the US recommended dietary allowances, were as follows: 305% of vitamin C, 247% of vitamin A, 313% of vitamin E, 92% of zinc, 120% of copper, and 49% of selenium. Compared with the omnivores, the vegans had significantly higher blood concentrations of beta-carotene, vitamin C, and vitamin E, as well as higher erythrocyte superoxide dismutase activity. These differences were also seen in pairs who were using no antioxidant supplements. The present data indicate that the "living food diet" provides significantly more dietary antioxidants than does the cooked, omnivorous diet, and that the long-term adherents to this diet have a better antioxidant status than do omnivorous control subjects.
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Antioxidantes/análisis , Dieta Vegetariana , Dieta/normas , Frutas , Verduras , Adulto , Anciano , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/sangre , Carotenoides/análisis , Carotenoides/sangre , Estudios Transversales , Ingestión de Alimentos , Eritrocitos/enzimología , Femenino , Glutatión Peroxidasa/análisis , Glutatión Peroxidasa/sangre , Humanos , Masculino , Persona de Mediana Edad , Superóxido Dismutasa/análisis , Superóxido Dismutasa/sangre , Factores de Tiempo , Vitamina E/administración & dosificación , Vitamina E/sangre , beta CarotenoRESUMEN
The present study examined the vitamin B-12 status in long-term adherents of a strict uncooked vegan diet called the "living food diet." The study was comprised of two parts. In the cross-sectional part, the data on serum vitamin B-12 concentrations and dietary intakes in 21 (1 male, 20 females) long-term adherents (mean 5.2 y, range 0.7-14) of the "living food diet" were compared with those of 21 omnivorous controls matched for sex, age, social status and residence. In the longitudinal part of the study, food consumption data were collected and blood samples were taken from nine "living food eaters" (1 male, 8 females) on two occasions 2 y apart. The cross-sectional study revealed significantly (P < 0.001, paired t test) lower serum vitamin B-12 concentrations in the vegans (mean 193 pmol/L, range 35-408) compared with their matched omnivorous controls (311, 131-482). In the vegan group, total vitamin B-12 intake correlated significantly (r = 0.63, P < 0.01) with serum vitamin B-12 concentration. The vegans consuming Nori and/or Chlorella seaweeds (n = 16) had serum vitamin B-12 concentrations twice as high as those not using these seaweeds (n = 5) (mean 221 pmol/L, range 75-408, vs. 105, 35-252, P = 0.025). In the longitudinal study, six of nine vegans showed slow, but consistent deterioration of vitamin B-12 status over a 2-y observation period. On the basis of these results we conclude that some seaweeds consumed in large amounts can supply adequate amounts of bioavailable vitamin B-12.(ABSTRACT TRUNCATED AT 250 WORDS)
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Dieta Vegetariana , Evaluación Nutricional , Algas Marinas , Vitamina B 12/sangre , Adulto , Anciano , Bilirrubina/sangre , Disponibilidad Biológica , Recuento de Células Sanguíneas , Creatinina/sangre , Estudios Transversales , Femenino , Ferritinas/sangre , Hemoglobinas/análisis , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Clase Social , Factores de Tiempo , Transferrina/análisis , Vitamina B 12/análisis , Vitamina B 12/farmacocinéticaAsunto(s)
Avena/fisiología , HDL-Colesterol/sangre , Colesterol/sangre , Fibras de la Dieta/uso terapéutico , Hígado Graso/dietoterapia , Animales , HDL-Colesterol/efectos de los fármacos , Modelos Animales de Enfermedad , Hígado Graso/patología , Masculino , Tamaño de los Órganos , Ratas , Ratas Sprague-DawleyRESUMEN
Enzyme-inducing and cytotoxic effects of South African bedding materials were investigated using a mouse hepatoma cell line, Hepa-1, cell culture system. This cell culture system is a convenient and sensitive method for the screening of bedding materials for the presence of compounds that could be potentially harmful to animals and thus the experimental outcome. Cells were exposed to acetone extracts of the different materials or their components. Corn cobs displayed very little or no CYP1A1-inducing or cytotoxic effects, whilst vermiculite and unbleached pulp from pine and eucalyptus showed greater induction and cytotoxic properties. The latter properties were lower than those produced by the different recycled paper extracts. Pine shavings (Pinus elliottii) and the different wood components making up industrial sawdust expressed the highest cytotoxic and CYP1A1-inducing properties.
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Animales de Laboratorio , Muerte Celular , Sistema Enzimático del Citocromo P-450/biosíntesis , Vivienda para Animales , Crianza de Animales Domésticos , Animales , Celulosa/toxicidad , Inducción Enzimática , Neoplasias Hepáticas , Silicatos/toxicidad , Sudáfrica , Células Tumorales CultivadasRESUMEN
Cytochrome P450IA1 (CYP1A1) induction of Hepa-1 mouse and H4IIE rat hepatoma cell lines was compared using selected environmental samples. The results were in agreement for both cell lines: no induction was observed for the fly ash extract from peat combustion, an intermediate induction was found for the fly ash extract from biosludge combustion, and a strong induction was detected for natural peat extract. However, Hepa-1 responded to the samples more sensitively than did H4IIE: the half maximal induction (ED50) values for Hepa-1 were smaller than those for H4IIE. In a bacterial DNA repair assay without metabolic activation and in a mammalian sister chromatid exchange test in the presence of metabolic activation the samples were virtually non-genotoxic. Thus the CYP1A1-inducing potency and genotoxicity of the samples were not correlated. In light of these results, the CYP1A1 induction test might be a useful addition to conventional genotoxicity tests, which may fail to detect potentially harmful compounds/mixtures.
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Sistema Enzimático del Citocromo P-450/biosíntesis , Contaminantes Ambientales/toxicidad , Mutágenos/toxicidad , Animales , Hidrocarburo de Aril Hidroxilasas/biosíntesis , Células CHO , Carbono/toxicidad , Línea Celular , Células Cultivadas , Ceniza del Carbón , Cricetinae , Citocromo P-450 CYP1A1 , Reparación del ADN/efectos de los fármacos , ADN Bacteriano/genética , Inducción Enzimática/efectos de los fármacos , Escherichia coli/genética , Ratones , Pruebas de Mutagenicidad , Oxidorreductasas/biosíntesis , Material Particulado , Ratas , Intercambio de Cromátides Hermanas/efectos de los fármacos , Suelo , Células Tumorales CultivadasRESUMEN
The Hepa-1 enzyme induction assay (assay of the induction of CYP1A1 catalytic activities in the Hepa-1 mouse hepatoma cell line by various compounds or mixtures) was evaluated as an in vitro indicator of the CYP1A1-inducing potencies of laboratory rodent diets in vivo. C57BL/6J mice were fed for three weeks four selected commercially available diets (one semisynthetic and three standard natural ingredient diets) exhibiting different enzyme-inducing effects in the Hepa-1 assay. beta-Naphthoflavone mixed in a semisynthetic diet (33 and 330 mg/kg of diet) was used as a model inducer. CYP1A1-dependent enzyme activities (aryl hydrocarbon hydroxylase and 7-ethoxyresorufin O-deethylase) were measured in the small intestinal mucosa and liver. There was good agreement between the induction of CYP1A1 in vitro and in vivo: the rank order of the enzyme activities elicited by the diets was the same in the mice as in the Hepa-1 cells. The standard diets were less effective inducers than beta-naphthoflavone in the Hepa-1 cells and in the mice, especially in the small intestinal mucosa. The Hepa-1 enzyme induction assay thus seems to be a mechanistically sound, reliable and sensitive in vitro indicator of the CYP1A1-inducing potencies of laboratory rodent diets in vivo.
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Alimentación Animal , Sistema Enzimático del Citocromo P-450/biosíntesis , Mucosa Intestinal/enzimología , Hígado/enzimología , Alimentación Animal/toxicidad , Animales , Hidrocarburo de Aril Hidroxilasas/biosíntesis , Benzoflavonas/farmacología , Muerte Celular , Línea Celular , Citocromo P-450 CYP1A1 , Inducción Enzimática , Alimentos Formulados , Intestino Delgado/efectos de los fármacos , Intestino Delgado/enzimología , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Oxidorreductasas/biosíntesis , Células Tumorales Cultivadas , beta-naftoflavonaRESUMEN
Oat bran concentrated with respect to both soluble and insoluble dietary fibre was fed to adult rats, and its effects on serum cholesterol and liver fat infiltration were studied. The feeds contained 15, 30 or 45 g beta-glucan/kg, except in control groups where the fibre of the feed was cellulose. Half the experimental groups received the feeds with an addition of 10 g cholesterol and 2 g cholic acid/kg in order to create an hypercholesterolaemic condition. In normocholesterolaemic rats the concentrated oat bran did not cause any significant changes in serum cholesterol concentrations, but reduced liver weight compared with control group rats fed on the cellulose-containing diet. In hypercholesterolaemic rats the concentrated oat bran reduced serum total cholesterol and increased high-density-lipoprotein cholesterol concentration. The effect was seen already at the 15 g/kg concentration of beta-glucan, the higher doses tested did not significantly improve the effect. Infiltration of fat into liver cells, especially in the periportal areas, was observed only in hypercholesterolaemic animals. The fat infiltration was accentuated in proportion to the amount of oat-bran concentrate fed.
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Colesterol/sangre , Fibras de la Dieta , Grano Comestible , Hígado Graso/metabolismo , Hígado/metabolismo , Animales , Celulosa/administración & dosificación , Hígado Graso/patología , Glucanos/administración & dosificación , Hígado/patología , Masculino , RatasRESUMEN
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent inducer of ethoxyresorufin O-deethylase (EROD) and aldehyde dehydrogenase (EC 1.2.1.3., ALDH3) enzyme activities in the liver. Little is known about their inducibility by TCDD in the brain, although it may be a target organ for TCDD toxicity. Two strains of rat, Long-Evans (L-E) and Han/Wistar (H/W) exhibit an over 1000-fold difference in their LD50-values for TCDD. The induction of EROD and ALDH3 in discrete brain regions and in the liver of L-E and H/W rats were now compared at 10 days after TCDD exposure to assess the role of these responses in the strain difference. Liver EROD and ALDH3 were maximally induced at 5 micrograms/kg and 50 micrograms/kg, respectively, in both strains. In the brain 50 micrograms/kg TCDD was mostly needed to enhance EROD activity in both strains. The induction occurred especially in olfactory bulbs, but was also seen in the midbrain plus thalamus of both rat strains. The induced EROD activity in the olfactory bulb was almost totally abolished by a monoclonal antibody (Mab) 1-7-1 raised against CYP1A1. ALDH3 activities were increased more dose dependently in olfactory bulbs of H/W than L-E rats. In other brain areas measured, ALDH3 activities were induced more in L-E rats. Kinetic factors did not explain the differential induction of EROD and ALDH3 among discrete brain regions. We conclude that both EROD and ALDH3 are induced in the brain by TCDD although the activities are much lower than in the liver. The induction in the brain is region specific with olfactory bulbs being the most responsive area. As in the liver, the TCDD-induced activity of EROD in the brain is primarily associated with CYP1A1. According to the present findings, enzyme induction in the brain does not seem to have a crucial role in determining the strain susceptibility to the acute lethality of TCDD.
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Aldehído Deshidrogenasa/biosíntesis , Encéfalo/enzimología , Sistema Enzimático del Citocromo P-450/biosíntesis , Hígado/enzimología , Oxidorreductasas/biosíntesis , Dibenzodioxinas Policloradas/farmacología , Animales , Encéfalo/efectos de los fármacos , Citocromo P-450 CYP1A1 , Resistencia a Medicamentos , Inducción Enzimática/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas WistarRESUMEN
An oat bran concentrate was prepared by removing non-fibre components by cold-water wet-milling, resulting in a 2- to 3-fold concentration of soluble fibre, with beta-D-glucan as its main component. The concentrate was baked in bread which was consumed for 8 weeks by free-living men with mild to moderate hypercholesterolaemia. The effects on serum lipids were assessed in a randomized, double-blind, placebo-controlled trial. Despite the large daily dose (11.2 g) of beta-glucan, the beta-glucan-enriched bread had only a small and statistically non-significant effect on serum lipid concentrations. Probable reasons for the weakness of the effect could be the poor solubility of beta-glucan in the preparation, its enzymatic hydrolysis after ingestion, and the consequently low viscosity in the intestine.
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Carbohidratos de la Dieta/farmacología , Grano Comestible/química , Glucanos/farmacología , Hipercolesterolemia/sangre , Lípidos/sangre , Adulto , Apolipoproteínas/sangre , Presión Sanguínea/efectos de los fármacos , Carbohidratos de la Dieta/administración & dosificación , Método Doble Ciego , Glucanos/administración & dosificación , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The mouse hepatoma cell line Hepa-1 was shown to express an aldehyde dehydrogenase (ALDH) isozyme which was inducible by TCDD and carcinogenic polycyclic aromatic hydrocarbons. The induced activity could be detected with benzaldehyde as substrate and NADP as cofactor (B/NADP ALDH). As compared with rat liver and hepatoma cell lines, the response was moderate (maximally 5-fold). There was an apparent correlation between this specific form of ALDH and aryl hydrocarbon hydroxylase (AHH) in the Hepa-1 wild-type cell line--in terms of inducibility by several chemicals. However, the magnitude of the response was clearly smaller for ALDH than for AHH. Southern blot analysis showed that a homologous gene (class 3 ALDH) was present in the rat and mouse genome. The gene was also expressed in Hepa-1 and there was a good correlation between the increase of class 3 ALDH-specific mRNA and B/NADP ALDH enzyme activity after exposure of the Hepa-1 cells to TCDD. It is concluded that class 3 ALDH is inducible by certain chemicals in the mouse hepatoma cell line, although the respective enzyme is not inducible in mouse liver in vivo.
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Aldehído Deshidrogenasa/biosíntesis , Neoplasias Hepáticas Experimentales/enzimología , Aldehído Deshidrogenasa/genética , Animales , Hidrocarburo de Aril Hidroxilasas/biosíntesis , Carcinógenos/farmacología , Inducción Enzimática/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Ratones , Dibenzodioxinas Policloradas/farmacología , Compuestos Policíclicos/farmacología , ARN Mensajero/genética , Células Tumorales CultivadasRESUMEN
Extracts of several rodent diets were studied for their cytotoxic and aryl hydrocarbon hydroxylase-inducing properties by an in vitro method. The cell culture system based on a mouse hepatoma cell line (Hepa-1) was shown to be a convenient and sensitive method for screening of diets for these parameters implying the presence of compounds potentially harmful in vivo. Considerable differences among diets and batches were detected. Smallest effects were observed with a semipurified diet and with the unrefined diet which - contrary to other four unrefined diets - contained no fish.
Asunto(s)
Alimentación Animal/toxicidad , Hidrocarburo de Aril Hidroxilasas/metabolismo , Células Tumorales Cultivadas/enzimología , Animales , Supervivencia Celular , Dieta , RatonesRESUMEN
1. The inhibition of cholinesterase and carboxylesterase activities in the diisopropyl fluorophosphate (DFP) intoxication, and the inducibility of organophosphate (OP) detoxicating enzymes was studied in rats. 2. In phenobarbital (PB)-, but not in beta-naphthoflavone (NF)-pretreated rats, the activities of DFP-inhibited cholinesterases were 70-120% higher than in non-pretreated rats. Also the inhibition of the microsomal and cytosolic carboxylesterase activity in liver was efficiently antagonized by BP, but not by NF. 3. In vitro the microsomes from PB-treated rats detoxicated DFP probably by O-dealkylation, since no fluoride was released from DFP. Glutathione S-transferase did not detoxicate DFP. 4. 7-Pentoxyresorufin O-dealkylase, a specific enzyme of cytochrome P450IIB subfamily, was induced by PB, flumecinol, isosafrole and NF by 167- 61-, 26- and 1.6-fold, respectively. 7-Ethoxyresorufin O-deethylase, a marker enzyme of cytochrome P450IA subfamily, was induced by those agents 5-, 4-, 31- and 94-fold, given in the same order. Glutathione S-transferase, paraoxonase and DFPase activities were increased 0-72% by the tested inducers. 5. The results suggest that the cytochrome P450IIB subfamily, inducible by PB, participates in DFP detoxication by O-dealkylation. Its induction probably causes the protection against the cholinesterase inhibition by OPs.