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111.
Side‐Directed Transfer and Presystemic Metabolism of Selenoneine in a Human Intestinal Barrier Model
Isabelle Rohn Nina Kroepfl Julia Bornhorst Doris Kuehnelt Tanja Schwerdtle 《Molecular nutrition & food research》2019,63(12)
Scope : Selenoneine, a recently discovered selenium (Se) species mainly present in marine fish, is the Se analogue of ergothioneine, a sulfur‐containing purported antioxidant. Although similar properties have been proposed for selenoneine, data on its relevance to human health are yet scarce. Here, the transfer and presystemic metabolism of selenoneine in an in vitro model of the human intestinal barrier are investigated. Methods and results : Selenoneine and the reference species Se‐methylselenocysteine (MeSeCys) and selenite are applied to the Caco‐2 intestinal barrier model. Selenoneine is transferred in higher amounts, but with similar kinetics as selenite, while MeSeCys shows the highest permeability. In contrast to the reference species, transfer of selenoneine is directed toward the blood side. Cellular Se contents demonstrate that selenoneine is efficiently taken up by Caco‐2 cells. Moreover, HPLC/MS‐based Se speciation studies reveal a partial metabolism to Se‐methylselenoneine, a metabolite previously detected in human blood and urine. Conclusions : Selenoneine is likely to pass the intestinal barrier via transcellular, carrier‐mediated transport, is highly bioavailable to Caco‐2 cells and undergoes metabolic transformations. Therefore, further studies are needed to elucidate its possible health effects and to characterize the metabolism of selenoneine in humans. 相似文献
112.
Joanna Nadia John Bronlund Rajinder Paul Singh Harjinder Singh Gail M. Bornhorst 《Comprehensive Reviews in Food Science and Food Safety》2021,20(3):2660-2698
The digestion of starch-based foods in the small intestine as well as factors affecting their digestibility have been previously investigated and reviewed in detail. Starch digestibility has been studied both in vivo and in vitro, with increasing interest in the use of in vitro models. Although previous in vivo studies have indicated the effect of mastication and gastric digestion on the digestibility of solid starch-based foods, the physical breakdown of starch-based foods prior to small intestinal digestion is often less considered. Moreover, gastric digestion has received little attention in the attempt to understand the digestion of solid starch-based foods in the digestive tract. In this review, the physical breakdown of starch-based foods in the mouth and stomach, the quantification of these breakdown processes, and their links to physiological outcomes, such as gastric emptying and glycemic response, are discussed. In addition, the physical breakdown aspects related to gastric digestion that need to be considered when developing in vitro–in vivo correlation in starch digestion studies are discussed. The discussion demonstrates that physical breakdown prior to small intestinal digestion, especially during gastric digestion, should not be neglected in understanding the digestion of solid starch-based foods. 相似文献
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The effect of cholesterol supplementation on the hypocholesterolemia induced by glutamic acid feeding has been studied in
the Mongolian gerbil. Serum triglycerides and phospholipids and hepatic cholesterol and triglyceride contents have also been
studied during the control and glutamate feeding. Cholesterol supplementation (0.05% and 1.0%) did not diminish the hypocholesterolemic
response (20–24% decrease in serum cholesterol). The glutamate amino acid formula diet caused no change in serum triglyceride,
serum phospholipid, hepatic cholesterol and hepatic triglyceride content when compared to the control formula diet. No lesions
of the hypothalamic or paraventricular areas of the brain were noted on histological preparation in adult gerbils given large
amounts of glutamic acid orally. 相似文献
116.
The authors developed and tested a model in which children who perceive their parents to be insecure about their jobs are distracted cognitively, which in turn affects their academic performance negatively. Participants were 102 female and 18 male undergraduates (mean age?=?18 years), their fathers (mean age?=?49 years), and their mothers (mean age?=?47 years). Students completed questionnaires measuring perceived parental job insecurity, identification with parents, and cognitive difficulties; 3 months later, they also reported their midyear grades. Fathers and mothers each completed questionnaires assessing their job insecurity. Support for the model was obtained using LISREL 8, and as predicted, children's identification with their mothers and fathers moderated the relationship between their perceptions of their mothers' and fathers' job insecurity and their own cognitive difficulties. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
117.
Fitchett George; Rybarczyk Bruce D.; DeMarco Gail A.; Nicholas John J. 《Canadian Metallurgical Quarterly》1999,44(4):333
ABSTRACT. Objective: To investigate the protective and consolation models of the relationship between religion and health outcomes in medical rehabilitation patients. Design: Longitudinal study, data collected at admission, discharge, and 4 months postadmission. Measures: Religion measures were public and private religiosity, acceptance, positive and negative religious coping, and spiritual injury. Outcomes were self-report of activities of daily living (ADL), mobility, general health, depression, and life satisfaction. Participants: 96 medical rehabilitation inpatients; diagnoses included joint replacement, amputation, stroke, and other conditions. Results: The protective model of the relationship between religion and health was not supported; only limited support was found for the consolation model. In regression analyses, negative religious coping accounted for significant variance in follow-up ADL (5%) over and above that accounted for by admission ADL, depression, social support, and demographic variables. Subsequent item analysis indicated that anger with God explained more variance (9%) than the full negative religious coping scale. Conclusions: Religion did not promote better recovery or adjustment… (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
Differing cytotoxicity and bioavailability of selenite,methylselenocysteine, selenomethionine,selenosugar 1 and trimethylselenonium ion and their underlying metabolic transformations in human cells 下载免费PDF全文
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Marles RJ Barrett ML Barnes J Chavez ML Gardiner P Ko R Mahady GB Low Dog T Sarma ND Giancaspro GI Sharaf M Griffiths J 《Critical reviews in food science and nutrition》2011,51(7):593-604
The Dietary Supplements Information Expert Committee (DSI-EC) of the United States Pharmacopeial Convention (USP) reviews the safety of dietary supplements and dietary supplement ingredients for the purpose of determining whether they should be admitted as quality monographs into the United States Pharmacopeia and National Formulary (USP-NF). The United States Food and Drug Administration (FDA) has enforcement authority to pursue a misbranding action in those instances where a dietary supplement product indicates that it conforms to USP standards but fails to so conform. Recently DSI-EC undertook a safety evaluation of spirulina, a widely used dietary ingredient. DSI-EC reviewed information from human clinical trials, animal studies, and regulatory and pharmacopeial sources and analyzed 31 adverse event reports regarding spirulina to assess potential health concerns. At the conclusion of this review, DSI-EC assigned a Class A safety rating for Spirulina maxima and S. platensis, thereby permitting the admission of quality monographs for these dietary supplement ingredients in USP-NF. DSI-EC continually monitors reports concerning the safety of dietary supplements and dietary supplement ingredients for which USP dietary supplement monographs are developed. The DSI-EC may revisit the safety classification of spirulina as new information on this dietary ingredient becomes available. 相似文献