RESUMO
There are few longitudinal data on nutritional status and body composition of patients undergoing allogeneic hematopoietic cell transplantation (alloHCT). We assessed nutritional status of 105 patients before alloHCT and its course during the early post-transplant period to day +30 and day +100 via weight history, body mass index (BMI) normalized for gender and age, Subjective Global Assessment, phase angle normalized for gender, age, and BMI, and fat-free and body fat masses. Furthermore, we present a multivariate regression model investigating the impact of factors on body weight. At admission, 23.8% reported significant weight losses (>5%) in the previous 6 months, and we noted 31.5% with abnormal age- and sex-adjusted BMI values (îº10th, î¶90th percentiles). BMI decreased significantly (P<0.0001) in both periods by 11% in total, meaning a weight loss of 8.6±5.7 kg. Simultaneously, the patients experienced significant losses (P<0.0001) of both fat-free and body fat masses. Multivariate regression model revealed clinically relevant acute GVHD (parameter estimate 1.43; P=0.02) and moderate/severe anorexia (parameter estimate 1.07; P=0.058) as independent factors influencing early weight loss. In conclusion, our results show a significant deterioration in nutritional status during the early post-transplant period. Predominant alloHCT-associated complications such as anorexia and acute GVHD became evident as significant factors influencing nutritional status.
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Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/cirurgia , Transplante de Células-Tronco Hematopoéticas/métodos , Estado Nutricional/fisiologia , Adulto , Idoso , Índice de Massa Corporal , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Transplante Homólogo , Resultado do Tratamento , Adulto JovemRESUMO
Micronutrient status is increasingly recognized to play an important role in the health and well-being of pregnant women and in the development and long-term health of the offspring. On 26th - 28th February 2009, The Child Health Foundation invited leading experts in this area to a scientific workshop at Obergurgl, Austria to review and critically discuss current knowledge, to identify issues that may need to be addressed in future recommendations, and to highlight priorities and opportunities for future research. This report summarizes updated key conclusions of the workshop with regards to micronutrients' intake and physiological role related to mother, placenta and fetus, as well as relevance for adverse pregnancy and long-term outcomes.
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Micronutrientes/administração & dosagem , Micronutrientes/metabolismo , Gravidez/metabolismo , Ingestão de Alimentos/fisiologia , Feminino , HumanosRESUMO
BACKGROUND/OBJECTIVES: Mushrooms contain very little or any vitamin D(2) but are abundant in ergosterol, which can be converted into vitamin D(2) by ultraviolet (UV) irradiation. Our objective was to investigate the bioavailability of vitamin D(2) from vitamin D(2)-enhanced mushrooms by UV-B in humans, and comparing it with a vitamin D(2) supplement. SUBJECTS/METHODS: Fresh mushrooms were irradiated with an UV-B dose of 1.5 J/cm(2), increasing vitamin D(2) content from <1 to 491 µg/100 g and made to an experimental soup. In this 5-week, single-blinded, randomized, placebo-controlled trial, 26 young subjects with serum 25-hydroxyvitamin D (25OHD) ≤ 50 nmol/l were randomly assigned into three groups ((a) mushroom, (b) supplement and (c) placebo). They received during winter (a) 28,000 IU (700 µg) vitamin D(2) via the experimental soup, or (b) 28,000 IU vitamin D(2) via a supplement or (c) placebo, respectively. RESULTS: After 2 weeks, serum 25OHD was significantly higher in the mushroom than in the placebo group (P=0.001). The serum 25OHD concentrations in the mushroom and supplement groups rose significantly and similarly over the study period by 3.9 nmol/l (95% confidence interval (95% CI): 2.9, 4.8) and by 4.7 nmol/l per week (95% CI: 3.8, 5.7), respectively. CONCLUSIONS: We are the first to demonstrate in humans that the bioavailability of vitamin D(2) from vitamin D(2)-enhanced button mushrooms via UV-B irradiation was effective in improving vitamin D status and not different to a vitamin D(2) supplement. This trial was registered at http://germanctr.de as DRKS00000195.
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Agaricales/química , Agaricales/efeitos da radiação , Agaricus/química , Ergocalciferóis/administração & dosagem , Ergocalciferóis/farmacocinética , Vitamina D/análogos & derivados , Adulto , Agaricus/efeitos da radiação , Disponibilidade Biológica , Cálcio/sangue , Suplementos Nutricionais , Feminino , Humanos , Masculino , Estudos Prospectivos , Método Simples-Cego , Raios Ultravioleta , Vitamina D/sangue , Deficiência de Vitamina D/tratamento farmacológico , Adulto JovemRESUMO
A close cooperation between medical teams is necessary when calculating the fluid intake of parenterally fed patients. Fluids supplied parenterally, orally and enterally, other infusions, and additional fluid losses (e.g. diarrhea) must be considered. Targeted diagnostic monitoring (volume status) is required in patients with disturbed water or electrolyte balance. Fluid requirements of adults with normal hydration status is approximately 30-40 ml/kg body weight/d, but fluid needs usually increase during fever. Serum electrolyte concentrations should be determined prior to PN, and patients with normal fluid and electrolyte balance should receive intakes follwing standard recommendations with PN. Additional requirements should usually be administered via separate infusion pumps. Concentrated potassium (1 mval/ml) or 20% NaCl solutions should be infused via a central venous catheter. Electrolyte intake should be adjusted according to the results of regular laboratory analyses. Individual determination of electrolyte intake is required when electrolyte balance is initially altered (e.g. due to chronic diarrhea, recurring vomiting, renal insufficiency etc.). Vitamins and trace elements should be generally substituted in PN, unless there are contraindications. The supplementation of vitamins and trace elements is obligatory after a PN of >1 week. A standard dosage of vitamins and trace elements based on current dietary reference intakes for oral feeding is generally recommended unless certain clinical situations require other intakes.
Assuntos
Hidratação/métodos , Hidratação/normas , Distúrbios Nutricionais/prevenção & controle , Nutrição Parenteral/métodos , Nutrição Parenteral/normas , Guias de Prática Clínica como Assunto , Eletrólitos/administração & dosagem , Alemanha , Humanos , Oligoelementos/administração & dosagem , Vitaminas/administração & dosagem , Água/administração & dosagemRESUMO
Fortified food claiming to exert a special function are increasingly offered on the market. Antioxidants (vitamin C, E and beta-carotene) are the major compounds in fortified foods. Due to the fact that the fortified vitamins do not exceed the recommended daily allowances within a food there is no risk for the consumer. Even in speculative cases of accumulation of antioxidants from different fortfied food sources there is no real risk. However, fortified food should not be taken to compensate an unbalanced and unhealthy diet. This risk is far more real because fortified food contains only a few antioxidants whereas a balanced diet contains hundreds. Whether the consumer may have a benefit from fortified food has not yet been evaluated with respect to antioxidant vitamins.
Assuntos
Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus/prevenção & controle , Alimentos Fortificados/efeitos adversos , Vitaminas/administração & dosagem , Vitaminas/efeitos adversos , Medicina Baseada em Evidências , Humanos , Valor Nutritivo , Medição de Risco , Fatores de RiscoRESUMO
Over the last two or three decades meat and especially liver have been looked upon as unhealthy food with high fat content and carcinogenic potential. In addition, its content of highly valuable micronutrients has mostly been ignored. As a result, the mean uptake and serum levels of several micronutrients in the population are below the recommended levels. In the meantime, the contamination of liver with heavy metals and other contaminants has fallen far below the allowed thresholds and sometimes even below the detection limit while its content of micronutrients like iron, folate, selenium or zinc are still high. As a further advantage, the bioavailability of many micronutrients often is better from meat and liver then from plant sources. Considering these advantages and the low content of contaminants in meat and liver leads us to propose that meat - including liver - should be a regular part of a mixed and balanced healthy diet along with vegetables and fruits as the major components to ensure an optimal supply of micronutrients.
RESUMO
OBJECTIVE: Update of the Hohenheim consensus on monosodium glutamate from 1997: Summary and evaluation of recent knowledge with respect to physiology and safety of monosodium glutamate. DESIGN: Experts from a range of relevant disciplines received and considered a series of questions related to aspects of the topic. SETTING: University of Hohenheim, Stuttgart, Germany. METHOD: The experts met and discussed the questions and arrived at a consensus. CONCLUSION: Total intake of glutamate from food in European countries is generally stable and ranged from 5 to 12 g/day (free: ca. 1 g, protein-bound: ca. 10 g, added as flavor: ca. 0.4 g). L-Glutamate (GLU) from all sources is mainly used as energy fuel in enterocytes. A maximum intake of 6.000 [corrected] mg/kg body weight is regarded as safe. The general use of glutamate salts (monosodium-L-glutamate and others) as food additive can, thus, be regarded as harmless for the whole population. Even in unphysiologically high doses GLU will not trespass into fetal circulation. Further research work should, however, be done concerning the effects of high doses of a bolus supply at presence of an impaired blood brain barrier function. In situations with decreased appetite (e.g., elderly persons) palatability can be improved by low dose use of monosodium-L-glutamate.
Assuntos
Qualidade de Produtos para o Consumidor , Aditivos Alimentares/administração & dosagem , Aditivos Alimentares/efeitos adversos , Glutamato de Sódio/administração & dosagem , Glutamato de Sódio/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Regulação do Apetite/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Feminino , Aromatizantes/administração & dosagem , Aromatizantes/efeitos adversos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Gravidez , Efeitos Tardios da Exposição Pré-NatalRESUMO
Populations living in endemic malaria areas maybe exposed simultaneously to DDT and malaria infection. DDT may impair status of vitamins, which are implicated in the immunity and pathophysiology of malaria. To explore possible interactions, DDT residues, retinol, alpha-tocopherol, beta-carotene and cholesterol were measured in plasma samples of malaria-infected pregnant women (cases, n=50) and age matched malaria-free controls (n=58). DDT residues were found in all samples: mean (sd) total DDT levels of 29.7 and 32.7 ng/ml in cases and controls, respectively. Mean (sd) p,p'-DDT was higher in the controls than the cases (13.5 vs. 9.5 ng/ml, p=0.006). Malaria infection was associated with lower mean (sd) plasma retinol (0.69 vs. 1.23 micromol/L) and cholesterol (2.62 vs. 3.48 mmol/L) compared to controls (p<0.001). Mean (sd) plasma alpha-tocopherol (7.65 vs. 15.58 micromol/L) and alpha-tocopherol/cholesterol ratio (2.3 vs. 6.7 micromol/L/mmol/L) were significantly lower among the controls (p<0.001). Mean (sd) plasma beta-carotene was low (<0.3 micromol/L) in both groups, but higher among malaria cases (0.19 vs. 0.15 micromol/L). Plasma retinol among the controls showed highly significant positive correlations with individual DDT compounds, particularly with p,p'-DDT (r=0.51, p<0.001). Plasma alpha-tocopherol and beta-carotene seemed not to be affected by DDT residues.
Assuntos
DDT/toxicidade , Poluentes Ambientais/toxicidade , Malária/sangue , Vitamina A/sangue , alfa-Tocoferol/sangue , beta Caroteno/sangue , Antioxidantes/farmacologia , Estudos de Casos e Controles , Feminino , Humanos , Malária/complicações , Gravidez , TailândiaRESUMO
The effect of non-selective (theophylline) inhibition of cyclic AMP breakdown on norepinephrine stimulated lipolysis rate was investigated in subcutaneous adipose tissue of obese subjects. In addition, changes in interstitial glucose and lactate concentration were assessed by means of the microdialysis technique. The interaction of endogenous released insulin and theophylline on adipocyte metabolism was determined. Theophylline and norepinephrine alone increased glycerol outflow significantly. When both agents were perfused in combination, interstitial glycerol concentration increased further. The enhanced glycerol level due to theophylline application was slightly decreased by insulin. In the presence of theophylline, extracellular glucose concentration increased, in contrast to the catecholamine. Norepinephrine decreased interstitial glucose level. When both drugs were added in combination, the level of interstitial glucose increased to about 1 mM, greater than with theophylline alone. With each intervention, lactate was synthesized. Local adipose tissue blood flow was increased by theophylline and theophylline plus norepinephrine. In conclusion, post-receptor mechanisms increased norepinephrine maximal stimulated lipolysis rate in subcutaneous adipose tissue. Glucose uptake was inhibited by the non-specific inhibitor of phosphodiesterase. The effect of insulin on inhibition of lipolysis was modest but sustained in the presence of high theophylline (10(-4) M) concentration. Phosphodiesterase activity may be relatively low in obese subjects in comparison with lean subjects. In lean subjects theophylline caused a transient reversal of the antilipolytic effect of insulin.
Assuntos
Tecido Adiposo/metabolismo , Obesidade/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Tecido Adiposo/irrigação sanguínea , Tecido Adiposo/enzimologia , Agonistas alfa-Adrenérgicos/farmacologia , Adulto , AMP Cíclico/metabolismo , Impedância Elétrica , Feminino , Glucose/metabolismo , Glicerol/metabolismo , Humanos , Cinética , Ácido Láctico/metabolismo , Lipólise/efeitos dos fármacos , Microdiálise , Pessoa de Meia-Idade , Norepinefrina/farmacologia , Obesidade/enzimologia , Inibidores de Fosfodiesterase/farmacologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Teofilina/farmacologiaRESUMO
BACKGROUND: Iron is an essential micronutrient but also a major catalyst of oxidative and inflammatory reactions. OBJECTIVE: To evaluate the potential utility of selected biomarkers in blood or urine to indicate in vivo oxidative or inflammatory response to oral iron intake at pharmacological doses. METHODS: Three healthy volunteers provided morning, fasting samples of blood and urine on up to 13 study days--3 before, 7 during and 3 following a 7-consecutive-day period of receiving 120 mg of iron per day as ferrous sulfate in commercially available syrup. A series of 23 biomarkers were measured on each collection of biological fluids to monitor iron-responsive changes in biomarkers related to hematological or iron status, inflammation and in vivo oxidation. RESULTS: Among the inflammatory biomarkers measured, white blood cells, serum CRP and urinary neopterin showed no response to iron dosing. Only circulating interleukin-4 (IL-4) and TNF-alpha had abnormal responses with a time association to the oral iron intake. Among the oxidative biomarkers, expression of blood superoxide dismutase (SOD), hemoxygenase-1, catalase as well as circulating thiobarbituric acid reactive substances (TBARS), total oxidative capacity and carbonyl proteins were stable in response to iron exposure. Only urinary TBARS, 8-hydroxy-2-desoxyguanosine and isoprostanes evidenced consistent or suggestive responses to ingestion of the iron challenge. Serum hepcidin concentration increased dramatically in all three subjects after only the first 120 mg dose of iron, and remained elevated even 9 days after cessation of the iron intervention. CONCLUSIONS: Most of the candidate biomarkers show very limited promise as response-indicators to oral iron dosing at the 120 mg dosages or lower, but circulating IL-4, TNF-alpha as well as urinary TBARS, 8-hydroxy-2-desoxyguanosine and isoprostanes showed potential utility as reliable indicators of oxidative and inflammatory response to oral ferrous sulfate.
Assuntos
Compostos Ferrosos/toxicidade , Inflamação/sangue , Inflamação/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , Administração Oral , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Feminino , Testes Hematológicos/métodos , Humanos , Inflamação/urina , Masculino , Estresse Oxidativo/fisiologia , Projetos PilotoRESUMO
Meat is frequently associated with a "negative" health image due to its "high" fat content and in the case of red meat is seen as a cancer-promoting food. Therefore, a low meat intake, especially red meat is recommended to avoid the risk of cancer, obesity and metabolic syndrome. However, this discussion overlooks the fact, that meat is an important source for some of micronutrients such as iron, selenium, vitamins A, B12 and folic acid. These micronutrients are either not present in plant derived food or have poor bioavailability. In addition, meat as a protein rich and carbohydrate "low" product contributes to a low glycemic index which is assumed to be "beneficial" with respect to overweight, the development of diabetes and cancer (insulin resistance hypothesis). Taken together meat is an important nutrient for human health and development. As an essential part of a mixed diet, meat ensures adequate delivery of essential micronutrients and amino acids and is involved in regulatory processes of energy metabolism.
RESUMO
BACKGROUND AND AIMS: Liver surgery usually involves ischemia and reperfusion (I/R) which results in oxidative stress and cell damage. The administration of antioxidants should diminish or prevent this damage. The purpose of this study was to investigate the effect of the antioxidant vitamin E on I/R injury. METHODS: We carried out a placebo-controlled double-blind study on 68 patients undergoing elective, tumor-related, partial liver resection. 47 patients were qualified for the per protocol population based evaluation. The patients were randomly assigned to two groups. The day before surgery one group received three infusions containing vitamin E (600 IU=540 mg vitamin E emulsion). The other group received three infusions of placebo. RESULTS: Length of stay in the intensive care unit (ICU) was significantly shorter in the verum group than in the placebo group (P<0.05). There were signs of improvement for AUC AST (P<0.05), ALT and GLDH in the verum group after surgery. Serum vitamin E concentration increased after administration of vitamin E infusion and declined in both treatment groups after surgery (P<0.01). In the verum group vitamin E deficiency was prevented while vitamin E concentration remained low in the placebo group (P<0.01). CONCLUSIONS: The findings from this study indicate that preoperative administration of vitamin E is safe and that this treatment may have beneficial effects by reducing the impact of I/R injury in liver surgery.
Assuntos
Antioxidantes/farmacologia , Fígado/cirurgia , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Vitamina E/farmacologia , Adulto , Idoso , Área Sob a Curva , Método Duplo-Cego , Feminino , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Fígado/enzimologia , Fígado/lesões , Masculino , Pessoa de Meia-Idade , Nutrição Parenteral , Projetos PilotoRESUMO
BACKGROUND: Patients on dietary, weight-reducing treatment commonly are advised against alcohol consumption. In light of the widespread use of alcoholic beverages and the well-established benefits of light to moderate alcohol consumption in risk reduction, a revision of dietary treatment recommendations may be warranted. OBJECTIVE: To investigate whether daily consumption of moderate amounts of alcohol influences the effectiveness of an energy-restricted diet in overweight and obese subjects. DESIGN: A prospective randomized clinical trial was conducted, with a 3-months intervention period and two isocaloric dietary regimens containing 6.3 MJ (1500 kcal) each, one with 10% of energy from white wine and one with 10% of energy from grape juice. The trial was performed in obese subjects being recruited from the Obesity Outpatient Clinic at the University Hospital, Ulm, who all habitually consumed moderate amounts of alcohol. Out of 87 patients, 49 were eligible to participate and 40 completed the study (age 48.1+/-11.4 y, BMI 34.2+/-6.4 kg/m(2)). Efficacy parameters were body weight and biomarkers of good health. RESULTS: All subjects achieved significant body weight reduction. Weight loss in the grape juice group and white wine group was 3.75+/-0.46 and 4.73+/-0.53 kg, respectively. Percent body fat, waist circumference, blood pressure, blood glucose, insulin, triglycerides, and cholesterol were reduced. The antioxidant status was unchanged, as were liver enzyme activities and other safety parameters. There were no significant differences between the groups. CONCLUSIONS: An energy-restricted diet is effective in overweight and obese subjects used to drinking moderate amounts of alcohol. A diet with 10% of energy derived from white wine is as effective as an isocaloric diet with 10% of energy derived from grape juice.
Assuntos
Consumo de Bebidas Alcoólicas , Peso Corporal , Obesidade/dietoterapia , Vinho , Bebidas , Dieta Redutora , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , VitisRESUMO
OBJECTIVE: High-dose vitamin C therapy might mediate beneficial clinical effects by counteracting reactive oxygen species. However, concerns are raised whether this approach might provoke diametrical (ie pro-oxidative) effects. The objective was to determine ascorbyl free radical (AFR) concentrations and potential variables of pro-oxidative damage. DESIGN: Crossover study; six healthy males received daily infusions of 750 or 7500 mg vitamin C for six consecutive days. Fasting concentrations of vitamin C and AFR were determined daily. On day 1, concentrations of vitamin C and AFR were measured at 0.25, 0.5, 1, 2, 4 and 8 h post infusion. Plasma concentrations of thiobarbituric acid-reactive substances (TBARS), tocopherol and urine concentrations of 8-oxoguanosine were determined on days 1 and 6. RESULTS: Kinetic studies on day 1 showed that concentrations of vitamin C and AFR displayed parallel dose- and time-dependent kinetics and elimination was highly efficient. Vitamin C and AFR fasting concentrations on days 2-6 were slightly above the baseline, suggesting new, stable steady states. TBARS decreased in both groups, whereas tocopherol and 8-oxoguanosine concentrations remained unchanged. CONCLUSION: Kinetics of AFR largely depend on plasma vitamin C concentrations and AFR is eliminated efficiently. Our data do not support induction of pro-oxidative effects in healthy volunteers given intravenous high-dose vitamin C. SPONSORSHIP: Pascoe Pharmazeutische Präparate GmbH, Giessen, Germany.
Assuntos
Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Radicais Livres/sangue , Guanosina/análogos & derivados , Espécies Reativas de Oxigênio/antagonistas & inibidores , Adulto , Antioxidantes/administração & dosagem , Antioxidantes/farmacocinética , Ácido Ascórbico/farmacocinética , Estudos Cross-Over , Relação Dose-Resposta a Droga , Jejum , Sequestradores de Radicais Livres/administração & dosagem , Sequestradores de Radicais Livres/sangue , Sequestradores de Radicais Livres/farmacocinética , Guanosina/urina , Humanos , Infusões Intravenosas , Masculino , Oxirredução , Estresse Oxidativo , Estudos Prospectivos , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
Vitamin-A is essential for growth and development of cells and tissues. In its active form, retinoic acid, it controls the regular differentiation as a ligand for retinoic acid receptors (RAR, RXR) and is involved in the integration (gap junction formation) of cell formations [Nature 37 (1994) 528; International Review of Cytology. San Diego Academic Press, 1-31]. Vitamin-A plays a substantial role, especially in the respiratory epithelium and the lung. During moderate vitamin-A-deficiency, the incidence for diseases of the respiratory tract is considerably increased and repeated respiratory infections can be influenced therapeutically by a moderate vitamin-A-supplementation [Aust. Paediatr. J. 22 (1986) 95; Lancet 338 (1991) 67]. In addition to the importance of the vitamin for the lung function, vitamin-A is also responsible for the development of many tissues and cells as well as for the embryonic lung development. Recent studies proved that the control occurs by different expressions of retinoid receptors as well as by time-dependent changes of the vitamin-A-metabolism respectively via cellular vitamin-A-binding proteins (CRBP: cytoplasmatic retinol binding protein; CRABP: cytoplasmatic retinoic acid binding protein).
Assuntos
Pulmão/crescimento & desenvolvimento , Pulmão/metabolismo , Mucosa Respiratória/metabolismo , Vitamina A/metabolismo , Animais , Humanos , Pulmão/embriologia , Receptores do Ácido Retinoico/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/efeitos dos fármacos , Proteínas de Ligação ao Retinol/metabolismo , Proteínas Celulares de Ligação ao Retinol , Tretinoína/metabolismo , Vitamina A/farmacologia , Deficiência de Vitamina A/metabolismoRESUMO
Retinoids have been reported to produce regressions in metaplastic changes of the mucosal epithelium. In order to define the role of these micronutrients in the prevention of squamous metaplasia of the oral cavity, it is necessary to measure their uptake in target tissues such as the buccal mucosal epithelium. We demonstrated in a trial that retinyl palmitate applied topically via a toothpaste is taken up by buccal mucosal cells in young healthy volunteers. In the randomised, parallel-designed, placebo-controlled and double-blind trial, forty volunteers divided in two groups cleaned their teeth either with a placebo toothpaste or a retinyl palmitate-containing toothpaste (1 mg/g) for 56 d. Buccal mucosal cells samples were taken from the healthy volunteers during the retinyl palmitate application and the following wash-out phase to determine the concentration of retinyl palmitate and retinol by HPLC. Supplementary blood samples were taken from the volunteers on days 0 and 56 to investigate changes in plasma retinyl palmitate and retinol concentrations. Results from only thirty participants (sixteen placebo and fourteen treated subjects) were used in the statistical evaluation as the remaining sample results were spoiled by a technical defect during the HPLC analysis. A significant (P<0.05) uptake of retinyl palmitate in buccal mucosal cells after 7 d and a significant (P<0.05) increase of plasma retinol after 17 d was demonstrated in our present study. The uptake of retinyl palmitate and the following hydrolysis to retinol led to an enrichment of vitamin A in buccal mucosal cells.
Assuntos
Mucosa Bucal/metabolismo , Vitamina A/análogos & derivados , Vitamina A/administração & dosagem , Vitamina A/metabolismo , Absorção , Administração Tópica , Adulto , Cromatografia Líquida de Alta Pressão , Diterpenos , Método Duplo-Cego , Feminino , Humanos , Masculino , Mucosa Bucal/química , Ésteres de Retinil , Cremes Dentais , Vitamina A/análiseRESUMO
UNLABELLED: A lower intake of carotenoids is associated with an increased risk of colorectal cancer. In order to take advantage of the chemopreventive properties of carotenoids, it is necessary to determine carotenoid concentration at the target tissue. As early stages in the adenoma-carcinoma sequence of colorectal cancer might be susceptible to chemoprevention, we sought to determine carotenoid concentrations in biopsies from colorectal adenomas. METHODS: Biopsies from colorectal adenomas and non-involved mucosa were taken from seven patients. For controls, biopsies were obtained from the ascending and descending colon of patients without polyps (n = 5). Concentration of carotenoids (alpha-, beta-carotene, lutein, lycopene, zeaxanthin, beta-cryptoxanthin) were determined by optimizing gradient HPLC-analysis. Results are expressed as pmol/microg DNA. RESULTS: Except for alpha-carotene, all carotenoids could reliably be detected in all specimens. In control patients carotenoid concentrations were highest in the ascending colon, being followed by the descending colon and non-involved mucosa from polyp-carriers. In colorectal adenomas all carotenoids were significantly reduced as compared to-non-involved mucosa (beta-carotene: 0.37 vs 0.19, P<0.03; lycopene: 0.34 vs 0.21, P<0.06, beta-cryptoxanthin: 0.14 vs 0.09, P<0.03, zeaxanthin: 0.18 vs 0.09, P<0.02; lutein: 0.18 vs 0.13,P <0.02). CONCLUSION: All carotenoids investigated are reduced in colorectal adenomas, suggesting that mucosal carotenoids could serve as biomarkers for predisposition to colorectal cancer. Moreover, anti-tumor activity exerted by carotenoids is limited due to mucosal depletion. We speculate that supplementation of a larger array of carotenoids might be beneficial for patients with colorectal adenoma.