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https://www.readbyqxmd.com/read/29025082/intestinal-absorption-of-vitamin%C3%A2-d-a-systematic-review
#1
Mariana Costa Silva, Tania Weber Furlanetto
Vitamin D is frequently prescribed as a supplement, yet its absorption remains poorly understood. This systematic review was performed to evaluate data on mechanisms involved in the intestinal absorption of vitamin D. PubMed, Embase, and Cochrane Library databases were searched. The following studies were included: experimental laboratory studies of vitamin D absorption through the enterocyte brush-border membrane; absorption tests that used radiolabeled vitamin D; and clinical trials in adults that investigated a single dose of cholecalciferol or ergocalciferol and reported at least 2 measurements of serum cholecalciferol, ergocalciferol, or 25-hydroxyvitamin D...
August 17, 2017: Nutrition Reviews
https://www.readbyqxmd.com/read/28994704/characterization-of-mucosal-disaccharidases-from-human-intestine
#2
Mahdi Amiri, Hassan Y Naim
In this study, we used a brush border membrane (BBM) preparation from human small intestine to analyze the proportion and the activity of major intestinal disaccharidases, including sucrase-isomaltase (SI), maltase-glucoamylase (MGAM) and lactase-phlorizin hydrolase (LPH). SI, MGAM and LPH respectively constituted 8.2%, 2.7% and 1.4% of total BBM protein. The activity of SI and LPH decreased threefold after purification from the brush border membrane, which highlights the effect of membrane microdomains on the functional capacity of these enzymes...
October 10, 2017: Nutrients
https://www.readbyqxmd.com/read/28988287/kinetic-measurements-of-di-and-tripeptide-and-peptidomimetic-drug-transport-in-different-kidney-regions-using-the-fluorescent-membrane-potential-sensitive-dye-dis-c3-3
#3
Othman A Alghamdi, Nicola King, Graham L Jones, Pierre D J Moens
Tri- and dipeptides are transported in the kidney by PEPT1 and PEPT2 isoforms. The aim of this study was to investigate differences in transport kinetics between renal brush border (BBMV) and outer medulla (OMMV) membrane vesicles (where PEPT1 and PEPT2 are sequentially available) for a range of di- and tripeptides and peptidomimetic drugs. This was accomplished through the use of the potential-sensitive fluorescent dye 3,3'-dipropylthiacarbocyanine iodide [DiS-C3-(3)]. BBMV and OMMV were prepared from the rat kidney using standard techniques...
October 7, 2017: Journal of Membrane Biology
https://www.readbyqxmd.com/read/28978534/nmr-spectroscopy-and-electron-microscopy-identification-of-metabolic-and-ultrastructural-changes-to-the-kidney-following-ischemia-reperfusion-injury
#4
Tafadzwa Chihanga, Qing Ma, Jenna D Nicholson, Hannah N Ruby, Richard E Edelmann, Prasad Devarajan, Michael A Kennedy
Cellular, molecular, and ultrastructural nephron changes associated with ischemia reperfusion injury-induced acute kidney injury (IRI-AKI) are not completely understood. Here, a multidisciplinary study was used to identify nephron changes in a mouse model of IRI-AKI. Histological analyses indicated distended Bowman's glomerular spaces and proximal and distal tubules. Increased filtrate volume in nephrons was caused by reduced water reabsorption by severely damaged proximal tubule brush borders and blocked flow of filtrate into collecting tubules by mucoprotein casts in distal tubules...
October 4, 2017: American Journal of Physiology. Renal Physiology
https://www.readbyqxmd.com/read/28960133/%C3%AE-potential-changing-nanoparticles-as-cystic-fibrosis-transmembrane-conductance-regulator-gene-delivery-system-an-in-vitro-evaluation
#5
Felix Prüfert, Sonja Bonengel, Saskia Köllner, Janine Griesser, Matthew D Wilcox, Peter I Chater, Jeffrey P Pearson, Andreas Bernkop-Schnürch
AIM: Aim of the study was the development of ζ potential changing nanoparticles as gene delivery system for the cystic fibrosis transmembrane conductance regulator gene. METHODS: Chitosan and carboxymethyl cellulose were modified with phosphotyrosine, a substrate for the brush border enzyme alkaline phosphatase. With these synthesized derivatives, different nanoparticle formulations, including the cystic fibrosis transmembrane conductance regulator gene were prepared by ionic gelation...
September 29, 2017: Nanomedicine
https://www.readbyqxmd.com/read/28958733/identification-of-bacillus-thuringiensis-cry1abmod-binding-proteins-from-spodoptera-frugiperda
#6
Diana L Martínez de Castro, Blanca I García-Gómez, Isabel Gómez, Alejandra Bravo, Mario Soberón
Bacillus thuringiensis Cry toxins are currently used for pest control in transgenic crops but evolution of resistance by the insect pests threatens the use of this technology. The Cry1AbMod toxin was engineered to lack the alpha helix-1 of the parental Cry1Ab toxin and was shown to counter resistance to Cry1Ab and Cry1Ac toxins in different insect species including the fall armyworm Spodoptera frugiperda. In addition, Cry1AbMod showed enhanced toxicity to Cry1Ab-susceptible S. frugiperda populations. To gain insights into the mechanisms of this Cry1AbMod-enhanced toxicity, we isolated the Cry1AbMod toxin binding proteins from S...
September 25, 2017: Peptides
https://www.readbyqxmd.com/read/28944407/oral-thymoquinone-administration-ameliorates-the-effect-of-cisplatin-on-brush-border-membrane-enzymes-energy-metabolism-and-redox-status-in-rat-kidney
#7
Zeba Farooqui, Faaiza Shahid, Subuhi Abidi, Iqbal Parwez, Farah Khan
Therapeutic use of cisplatin (CP), an effective anticancer drug, is limited by dose dependent nephrotoxicity. Thymoquinone (TQ), the major Nigella sativa seed oil constituent has been shown to prevent progression of various renal disorders. The present study investigates the protective effect of TQ on CP-induced nephrotoxicity. Rats were divided into six groups viz. control, CP, CPTQ1, CPTQ2, CPTQ3, and TQ alone group. Animals in CP and TQ combination groups were administered TQ (0.5, 1.5, and 3 mg/kg bwt, orally) with single intraperitoneal dose of CP (6 mg/kg bwt)...
September 24, 2017: Naunyn-Schmiedeberg's Archives of Pharmacology
https://www.readbyqxmd.com/read/28944308/titanium-dioxide-nanoparticle-ingestion-alters-nutrient-absorption-in-an-in-vitro-model-of-the-small-intestine
#8
Zhongyuan Guo, Nicole J Martucci, Fabiola Moreno-Olivas, Elad Tako, Gretchen J Mahler
Ingestion of titanium dioxide (TiO2) nanoparticles from products such as agricultural chemicals, processed food, and nutritional supplements is nearly unavoidable. The gastrointestinal tract serves as a critical interface between the body and the external environment, and is the site of essential nutrient absorption. The goal of this study was to examine the effects of ingesting the 30 nm TiO2 nanoparticles with an in vitro cell culture model of the small intestinal epithelium, and to determine how acute or chronic exposure to nano-TiO2 influences intestinal barrier function, reactive oxygen species generation, proinflammatory signaling, nutrient absorption (iron, zinc, fatty acids), and brush border membrane enzyme function (intestinal alkaline phosphatase)...
January 2017: NanoImpact
https://www.readbyqxmd.com/read/28931466/1-alpha-25-dihydroxyvitamin-d3-up-regulates-the-expression-of-2-types-of-human-intestinal-alkaline-phosphatase-alternative-splicing-variants-in-caco-2-cells-and-may-be-an-important-regulator-of-their-expression-in-gut-homeostasis
#9
Seiko Noda, Asako Yamada, Kanae Nakaoka, Masae Goseki-Sone
Vitamin D insufficiency is associated with a greater risk of osteoporosis and also influences skeletal muscle functions, differentiation, and development. The principal function of vitamin D in calcium homeostasis is to increase the absorption of calcium from the intestine, and the level of alkaline phosphatase (ALP) activity, a differentiation marker for intestinal epithelial cells, is regulated by vitamin D. Intestinal-type ALP is expressed at a high concentration in the brush border membrane of intestinal epithelial cells, and is known to be affected by several kinds of nutrients...
August 4, 2017: Nutrition Research
https://www.readbyqxmd.com/read/28895768/protective-effects-of-taurine-against-renal-ischemia-reperfusion-injury-in-rats-by-inhibition-of-gelatinases-mmp-2-and-mmp-9-and-p38-mitogen-activated-protein-kinase-signaling
#10
Z Cavdar, C Ural, A Celik, S Arslan, G Terzioglu, S Ozbal, S Yildiz, U B Ergur, E Guneli, T Camsari, G Akdogan
Dysregulated expression of matrix metalloproteinases (MMPs) is closely associated with the pathogenesis of renal ischemia/reperfusion injury (I/R). The production of excessive reactive oxygen species (ROS) causes tissue damage. Increased ROS production causes activation of p38 mitogen-activated protein kinase (MAPK) signaling, which participates in gene regulation of MMPs, especially MMP-2 and MMP-9 (gelatinases). Taurine (2-aminoethanesulfonic acid) in mammalian cells functions in bile acid conjugation, maintenance of calcium homeostasis, osmoregulation, membrane stabilization, and antioxidation, antiinflammatory, and antiapoptotic action...
September 12, 2017: Biotechnic & Histochemistry: Official Publication of the Biological Stain Commission
https://www.readbyqxmd.com/read/28882822/both-nherf3-and-nherf2-are-necessary-for-multiple-aspects-of-acute-regulation-of-nhe3-by-elevated-ca-2-cgmp-and-lysophosphatidic-acid
#11
Leela Rani Avula, Tiane Chen, Olga Kovbasnjuk, Mark Donowitz
The intestinal epithelial brush border Na(+)/H(+) exchanger NHE3 accounts for a large component of intestinal Na absorption. NHE3 is regulated during digestion by signaling complexes on its C-terminus that include the four multi-PDZ domain containing NHERF family proteins. Because the roles of each NHERF appear to vary based on the cell model or intestinal segment studied and because of our recent finding that a NHERF3-NHERF2 heterodimer appears important for NHE3 regulation in Caco-2 cells, we examined the role of NHERF3 and NHERF2 in homozygous C57BL/6 NHERF2 and NHERF3 KO mouse jejunum...
September 7, 2017: American Journal of Physiology. Gastrointestinal and Liver Physiology
https://www.readbyqxmd.com/read/28871404/assessment-of-bioavailable-b-vitamin-content-in-food-using-in-vitro-digestibility-assay-and-lc-ms-sida
#12
Toomas Paalme, Allan Vilbaste, Kaspar Kevvai, Ildar Nisamedtinov, Kristel Hälvin-Tanilas
Standardized analytical methods, where each B vitamin is extracted from a given sample individually using separate procedures, typically ensure that the extraction conditions provide the maximum recovery of each vitamin. However, in the human gastrointestinal tract (GIT), the extraction conditions are the same for all vitamins. Here, we present an analytically feasible extraction protocol that simulates conditions in the GIT and provides a measure of the content of bioavailable vitamins using LC-MS stable isotope dilution assay...
September 4, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28867347/functional-enterospheres-derived-in%C3%A2-vitro-from-human-pluripotent-stem%C3%A2-cells
#13
Rohan R Nadkarni, Soumeya Abed, Brian J Cox, Sonam Bhatia, Jennifer T Lau, Michael G Surette, Jonathan S Draper
Intestinal organoids derived from human pluripotent stem cells (hPSCs) are valuable in vitro research models that enable simplified access to human gastrointestinal tissues. Here, we report the in vitro generation of enterospheres (hEnS) from hPSC-derived gastrointestinal epithelial precursors. hEnS are cystic spheroids with a simple uniform structure composed entirely of intestinal epithelium. hEnS express markers of mature brush border cells and share a transcriptome profile similar to that of more mature intestinal organoids...
September 12, 2017: Stem Cell Reports
https://www.readbyqxmd.com/read/28862677/simulation-of-food-folate-digestion-and-bioavailability-of-an-oxidation-product-of-5-methyltetrahydrofolate
#14
Christiane Ringling, Michael Rychlik
Generating bioavailability data from in vivo studies is time-consuming and expensive. In vitro simulation can help to investigate factors influencing bioavailability or facilitate quantifying the impact of such factors. For folates, an efficient deconjugation of polyglutamates to the corresponding monoglutamates is crucial for bioavailability and highly dependent on the food matrix. Therefore, the bioaccessibility of folates of different foodstuffs was examined using a simulated digestion model with respect to folate stability and the efficiency of deconjugation...
September 1, 2017: Nutrients
https://www.readbyqxmd.com/read/28859534/larvicidal-and-pupicidal-evaluation-of-silver-nanoparticles-synthesized-using-aquilaria-sinensis-and-pogostemon-cablin-essential-oils-against-dengue-and-zika-viruses-vector-aedes-albopictus-mosquito-and-its-histopathological-analysis
#15
Hassan Ga'al, Hatem Fouad, Guofeng Mao, Jiaxin Tian, Mo Jianchu
Mosquitoes pose a threat to humans and animals, causing millions of deaths every year. Vector control by effective eco-friendly pesticides of natural origin is a serious issue that requires urgent attention. The employment of green-reducing extracts for nanoparticles biosynthesis in a rapid and single-step process represents a promising strategy. In this study, silver nanoparticles (AgNPs) were biofabricated using an essential oil of Aquilaria sinensis (AsEO) and Pogostemonis Herba essential oil of Pogostemon cablin (PcEO) in one step and cost-effective manner...
August 31, 2017: Artificial Cells, Nanomedicine, and Biotechnology
https://www.readbyqxmd.com/read/28855375/shear-stress-induces-non-canonical-autophagic-flux-in-intestinal-epithelial-monolayers
#16
Sun Wook Kim, Jonathan Ehrman, Mok-Ryeon Ahn, Jumpei Kondo, Andrea A Mancheno Lopez, Yun Sik Oh, Hanjune X Kim, Scott W Crawley, James R Goldenring, Matthew J Tyska, Erin C Rericha, Ken S Lau
Flow of fluids through the gut, such as milk from a neonatal diet, generates a shear stress on the unilaminar epithelium lining the lumen.  We report that exposure to physiological levels of fluid shear stress leads to the formation of large vacuoles, containing extracellular content, within polarizing intestinal epithelial cell monolayers.  These observations lead to two questions: how can cells lacking primary cilia transduce shear stress, and what molecular pathways support the formation of vacuoles that can exceed 80% of the cell volume...
August 30, 2017: Molecular Biology of the Cell
https://www.readbyqxmd.com/read/28837408/intestinal-surfactant-permeation-enhancers-and-their-interaction-with-enterocyte-cell-membranes-in-a-mucosal-explant-system
#17
E Michael Danielsen, Gert H Hansen
Intestinal permeation enhancers (PEs) are agents aimed to improve oral delivery of therapeutic drugs with poor bioavailability. The main permeability barrier for oral delivery is the intestinal epithelium, and PEs act to increase the paracellular and/or transcellular passage of drugs. Transcellular passage can be achieved by cell membrane permeabilization and/or by endocytic uptake and subsequent transcytosis. One broad class of PEs is surfactants which act by inserting into the cell membrane, thereby perturbing its integrity, but little is known about how the dynamics of the membrane are affected...
July 3, 2017: Tissue Barriers
https://www.readbyqxmd.com/read/28825699/an-apical-mrck-driven-morphogenetic-pathway-controls-epithelial-polarity
#18
Ceniz Zihni, Evi Vlassaks, Stephen Terry, Jeremy Carlton, Thomas King Chor Leung, Michael Olson, Franck Pichaud, Maria Susana Balda, Karl Matter
Polarized epithelia develop distinct cell surface domains, with the apical membrane acquiring characteristic morphological features such as microvilli. Cell polarization is driven by polarity determinants including the evolutionarily conserved partitioning-defective (PAR) proteins that are separated into distinct cortical domains. PAR protein segregation is thought to be a consequence of asymmetric actomyosin contractions. The mechanism of activation of apically polarized actomyosin contractility is unknown...
September 2017: Nature Cell Biology
https://www.readbyqxmd.com/read/28821162/oral-administration-of-thymoquinone-mitigates-the-effect-of-cisplatin-on-brush-border-membrane-enzymes-energy-metabolism-and-antioxidant-system-in-rat-intestine
#19
Faaiza Shahid, Zeba Farooqui, Subuhi Abidi, Iqbal Parwez, Farah Khan
Cisplatin (CP) is a widely used chemotherapeutic agent that elicits severe gastrointestinal toxicity. Nigella sativa, a member of family Ranunculaceae, is one of the most revered medicinal plant known for its numerous health benefits. Thymoquinone (TQ), a major bioactive component derived from the volatile oil of Nigella sativa seeds, has been shown to improve gastrointestinal functions in animal models of acute gastric/intestinal injury. In view of this, the aim of the present study was to investigate the protective effect of TQ on CP induced toxicity in rat intestine and to elucidate the mechanism underlying these effects...
October 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28813122/morphological-alterations-in-the-jejunal-mucosa-of-aged-rats-and-the-possible-protective-role-of-green-tea
#20
Zeinab Abel-Rehim Hassan, Agata Zauszkiewicz-Pawlak, Shaimaa A Abdelrahman, Sami Algaidi, Maha Desouky, Sally M Shalaby
INTRODUCTION: Gastrointestinal disorders become more prevalent with ageing. This study is aimed to describe morphological changes that occur in the jejunal mucosa of male albino rats as a result of ageing and the protective effect of green tea supplements. MATERIAL AND METHODS: The experiment was performed on sixty rats: thirty young-adult (6-month old, body mass 200-220 g) and thirty old (24-month-old, body mass 220-260 g) animals. Each group was further divided into two subgroups (n = 15 each): control rats and green tea-treated rats that received 1...
August 16, 2017: Folia Histochemica et Cytobiologica
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