scholarly journals Measurement of resistant starch in vitro and in vivo

1996 ◽  
Vol 75 (5) ◽  
pp. 749-755 ◽  
Author(s):  
Hans N. Englyst ◽  
Susan M. Kingman ◽  
Geoffrey J. Hudson ◽  
John H. Cummings
Keyword(s):  
Small Intestine ◽  
Resistant Starch ◽  
Degradation Products ◽  
Physical Structure ◽  
Starch Degradation ◽  
Plant Foods ◽  
Analytical Technique ◽  
Human Small Intestine

The digestibility of the starch in plant foods is highly variable, and is dependent on a number of factors, including the physical structure of both the starch and the food matrix. An in vitro technique has been developed to categorize starch in plant foods according to its likely rate and extent of digestion in the human small intestine. The in vitro method provides values for rapidly digestible starch, slowly digestible starch and resistant starch (RS). In the present study values for the RS content of foods, as measured by the analytical technique, were compared with the recovery of starch from these foods when fed to healthy ileostomates. Nine ileostomy subjects were given a polysaccharide-free diet with a breakfast supplement, on each of 2 d (two subjects) or 3 d (seven subjects), of biscuits made from wheat, potato or banana flours or from moist-heat-processed wheat or maize flours. RS intakes measured in vifro ranged from 8·5 to 15·0 g/d for the test biscuits, and mean starch recoveries in ileostomy effluent were 100·4 (n5, range 91−106)% of those values, but there was substantial variation between individuals. It is proposed that RS is defined as ‘the sum of starch and starch-degradation products that, on average, reach the human large intestine’. The analytical method for the measurement of RS in vitro based on this definition is shown to provide an accurate prediction of the average amount of starch that is likely to escape complete digestion and absorption in the human small intestine.

scholarly journals Measurement of rapidly available glucose (RAG) in plant foods: a potential in vitro predictor of the glycaemic response

1996 ◽  
Vol 75 (3) ◽  
pp. 327-337 ◽  
Author(s):  
Hans N Englyst ◽  
Jan Veenstra ◽  
Geoffrey J Hudson
Keyword(s):  
Small Intestine ◽  
Direct Calculation ◽  
Simple Calculation ◽  
Glycaemic Index ◽  
Equal Weight ◽  
Glycaemic Response ◽  
Human Small Intestine ◽  
Reference Amount

AbstractThe glycaemic index (GI) is an in vivo measurement based on the glycaemicresponse to carbohydrate-containing foods, and allows foods to be ranked on the basis of the rate of digestion and absorption of the carbohydrates that they contain. GI values are normalizedto a reference amount of available carbohydrate and do not reflect the amounts of carbohydrate normally present in foods; for example, a food with a low content of carbohydrates will have a high GI value if that carbohydrate is digested and absorbed rapidly in the human small intestine. This is potentially confusing for a person wishing to control his or her blood glucoselevels by the choice of foods. The rate and extent of starch digestion in vitro has been measured using a technique that classifies starch into three major fractions: rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS). In addition, thistechnique gives a value for rapidly available glucose (RAG), which includes RDS, free glucose and the glucose moiety of sucrose. When the values for thirty-nine foods were expressed on the basis ofthe available carbohydrate content of these foods, highly significant (P<0·001) positive correlations were observed between GI and both RDS and RAG. The measurement of RAGin vitro provides values for direct calculation of the amount of glucose likely to be rapidly absorbed in the human small intestine and,thus, to influence blood glucose and insulin levels. These values can be used to compare foods, as eaten,on an equal-weight basis. Food-table RAG values would allow simple calculation of the total amount of RAG provided by single foods, by whole meals and by whole diets. Studies are planned in which RAG and the glycaemic response in man will be measured for identical food products.

scholarly journals Digestion of raw banana starch in the small intestine of healthy humans: structural features of resistant starch

1995 ◽  
Vol 73 (1) ◽  
pp. 111-123 ◽  
Author(s):  
N. Faisant ◽  
A. Buléon ◽  
P. Colonna ◽  
C. Molis ◽  
S. Lartigue ◽  
...  
Keyword(s):  
Small Intestine ◽  
Terminal Ileum ◽  
Resistant Starch ◽  
Structural Features ◽  
Intubation Technique ◽  
Healthy Humans ◽  
Freeze Dried ◽  
Green Banana

The digestion of freeze-dried green banana flour in the upper gut was studied by an intubation technique in six healthy subjects over a 14 h period. Of α-glucans ingested, 83.7 % reached the terminal ileum but were almost totally fermented in the colon. Structural study of the resistant fraction showed that a small part of the α-glucans which escaped digestion in the small intestine was composed of oligosaccharides from starch hydrolysis, whereas the rest was insoluble starch in granule form with physical characteristics similar to those of raw banana starch. Passage through the small intestine altered granule structure by increasing susceptibility to further α-amylase hydrolysis. Compared with resistant starch values in vivo, those obtained with the in vitro methods tested were inadequate to estimate the whole fraction of starch reaching the terminal ileum.

Electron probe x-ray microanalysis and electron microscopy of amino acid absorption and transport by the small intestine: inhibition by chemical poisons and correlation to the elemental composition of the epithelial cells

1986 ◽  
Vol 44 ◽  
pp. 134-135
Author(s):  
A. J. Tousimis
Keyword(s):  
Small Intestine ◽  
Amino Acid ◽  
Epithelial Cells ◽  
Elemental Composition ◽  
Isotope Labeling ◽  
Structural Components ◽  
X Ray ◽  
Human Small Intestine ◽  
Transport Studies

The elemental composition of amino acids is similar to that of the major structural components of the epithelial cells of the small intestine and other tissues. Therefore, their subcellular localization and concentration measurements are not possible by x-ray microanalysis. Radioactive isotope labeling: I131-tyrosine, Se75-methionine and S35-methionine have been successfully employed in numerous absorption and transport studies. The latter two have been utilized both in vitro and vivo, with similar results in the hamster and human small intestine. Non-radioactive Selenomethionine, since its absorption/transport behavior is assumed to be the same as that of Se75- methionine and S75-methionine could serve as a compound tracer for this amino acid.

Comparison of High Purity Factor IX Concentrates and a Prothrombin Complex Concentrate in a Canine Model of Thrombogenicity

1991 ◽  
Vol 66 (05) ◽  
pp. 609-613 ◽  
Author(s):  
I R MacGregor ◽  
J M Ferguson ◽  
L F McLaughlin ◽  
T Burnouf ◽  
C V Prowse
Keyword(s):  
High Purity ◽  
Time Course ◽  
Prothrombin Complex Concentrate ◽  
Degradation Products ◽  
Canine Model ◽  
Factor Ix ◽  
In Vitro Tests ◽  
Albumin Infusion

SummaryA non-stasis canine model of thrombogenicity has been used to evaluate batches of high purity factor IX concentrates from 4 manufacturers and a conventional prothrombin complex concentrate (PCC). Platelets, activated partial thromboplastin time (APTT), fibrinogen, fibrin(ogen) degradation products and fibrinopeptide A (FPA) were monitored before and after infusion of concentrate. Changes in FPA were found to be the most sensitive and reproducible indicator of thrombogenicity after infusion of batches of the PCC at doses of between 60 and 180 IU/kg, with a dose related delayed increase in FPA occurring. Total FPA generated after 100-120 IU/kg of 3 batches of PCC over the 3 h time course was 9-12 times that generated after albumin infusion. In contrast the amounts of FPA generated after 200 IU/kg of the 4 high purity factor IX products were in all cases similar to albumin infusion. It was noted that some batches of high purity concentrates had short NAPTTs indicating that current in vitro tests for potential thrombogenicity may be misleading in predicting the effects of these concentrates in vivo.

Accumulation of Macromolecular Particles in the Reticuloendothelial System (RES) Mediated by Platelet Aggregation and Disaggregation

1969 ◽  
Vol 22 (03) ◽  
pp. 496-507 ◽  
Author(s):  
W.G van Aken ◽  
J Vreeken
Keyword(s):  
Platelet Aggregation ◽  
Degradation Products ◽  
Reticuloendothelial System ◽  
Caproic Acid ◽  
Carbon Particles ◽  
Carbon Clearance ◽  
Aggregation And Disaggregation ◽  
Platelet Aggregates

SummaryCarbon particles cause platelet aggregation in vitro and in vivo. Prior studies established that substances which modify thrombocyte aggregation also influence the rate at which carbon is cleared from the blood.This study was performed in order to elucidate the mechanism by which the carbon-platelet aggregates specifically accumulate in the RES.Activation of fibrinolysis by urokinase or streptokinase reduced the carbon clearance rate, probably due to generated fibrinogen degradation products (FDP). Isolated FDP decreased the carbon clearance and caused disaggregation of platelets and particles in vitro. Inhibition of fibrinolysis by epsilon-amino-caproic acid (EACA), initially accelerated the disappearance of carbon and caused particle accumulation outside the RES, predominantly in the lungs. It is supposed that platelet aggregation and locally activated fibrinolysis act together in the clearance of particles. In the normal situation the RES with its well known low fibrinolytic activity, becomes the receptor of the particles.

The Effects of Brinolase (Fibrinolytic Enzyme from Aspergillus Oryzae) on Platelet Aggregation of Dog and Man

1972 ◽  
Vol 28 (01) ◽  
pp. 031-048 ◽  
Author(s):  
W. H. E Roschlau ◽  
R Gage
Keyword(s):  
Platelet Aggregation ◽  
Aspergillus Oryzae ◽  
Degradation Products ◽  
Blood Platelet ◽  
Human Platelets ◽  
Fibrinolytic Enzyme ◽  
Inhibitory Effects ◽  
Blood Platelet Aggregation

SummaryInhibition of blood platelet aggregation by brinolase (fibrinolytic enzyme from Aspergillus oryzae) has been demonstrated with human platelets in vitro and with dog platelets in vivo and in vitro, using both ADP and collagen as aggregating stimuli. It is suggested that the optimal inhibitory effects of brinolase occur indirectly through the generation of plasma fibrinogen degradation products, without compromising platelet viability, rather than by direct proteolysis of platelet structures.

scholarly journals Generation of tetracycline-controllable CYP3A4-expressing Caco-2 cells by the piggyBac transposon system

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Moe Ichikawa ◽  
Hiroki Akamine ◽  
Michika Murata ◽  
Sumito Ito ◽  
Kazuo Takayama ◽  
...  
Keyword(s):  
Small Intestine ◽  
Drug Absorption ◽  
Cell Model ◽  
Negative Effects ◽  
Piggybac Transposon ◽  
Drug Metabolizing Enzyme ◽  
Metabolizing Enzyme ◽  
Cyp3a4 Expression

AbstractCaco-2 cells are widely used as an in vitro intestinal epithelial cell model because they can form a monolayer and predict drug absorption with high accuracy. However, Caco-2 cells hardly express cytochrome P450 (CYP), a drug-metabolizing enzyme. It is known that CYP3A4 is the dominant drug-metabolizing enzyme in human small intestine. In this study, we generated CYP3A4-expressing Caco-2 (CYP3A4-Caco-2) cells and attempted to establish a model that can simultaneously evaluate drug absorption and metabolism. CYP3A4-Caco-2 cells were generated by piggyBac transposon vectors. A tetracycline-controllable CYP3A4 expression cassette (tet-on system) was stably transduced into Caco-2 cells, thus regulating the levels of CYP3A4 expression depending on the doxycycline concentration. The CYP3A4 expression levels in CYP3A4-Caco-2 cells cultured in the presence of doxycycline were similar to or higher than those of adult small intestine. The CYP3A4-Caco-2 cells had enough ability to metabolize midazolam, a substrate of CYP3A4. CYP3A4 overexpression had no negative effects on cell proliferation, barrier function, and P-glycoprotein activity in Caco-2 cells. Thus, we succeeded in establishing Caco-2 cells with CYP3A4 metabolizing activity comparable to in vivo human intestinal tissue. This cell line would be useful in pharmaceutical studies as a model that can simultaneously evaluate drug absorption and metabolism.

scholarly journals Glycemic Index of Gluten-Free Bread and Their Main Ingredients: A Systematic Review and Meta-Analysis

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 506
Author(s):  
Bernardo Romão ◽  
Ana Luísa Falcomer ◽  
Gabriela Palos ◽  
Sandra Cavalcante ◽  
Raquel Braz Assunção Botelho ◽  
...  
Keyword(s):  
Systematic Review ◽  
Glycemic Index ◽  
Resistant Starch ◽  
Web Of Science ◽  
Meta Analysis ◽  
Gluten Free ◽  
Inclusion Criteria ◽  
Glycemic Profile

This study aimed to perform a systematic review and meta-analysis of the glycemic index (GI) of gluten-free bread (GFB) and its main ingredients. The systematic review followed PRISMA guidelines, using seven electronic databases (PubMed, EMBASE, Scopus, Science Direct, Web of Science, gray literature research with Google Scholar, and patents with Google Patent tool), from inception to November 2020. Eighteen studies met the inclusion criteria evaluating 132 GFB samples. Five articles tested GI in vivo, eleven in vitro; and two studies tested both methods. The analysis showed that 60.7% (95% CI: 40.2–78.1%) of the samples presented high glycemic indexes, evidencing a high glycemic profile for GFB. Only 18.2% (95% CI: 11.7–27.2%) of the bread samples presented in the studies were classified as a low GI. Meta-analysis presented moderate/low heterogenicity between studies (I2 = 61% and <1% for both high and low GIs) and reinforced the proportion of high GIs. Lower GIs were found in formulations based on Colocasia esculenta flour or enriched with fiber, yogurt and curd cheese, sourdough, psyllium, hydrocolloids, enzymes, fructans, and resistant starch, highlighting the efficacy of these ingredients to lower GFBs’ GI. GFB tends to present high GI, impacting the development of chronic diseases when consumed.

scholarly journals Absorption of lactulose from mammalian gastrointestinal tract

1979 ◽  
Vol 41 (1) ◽  
pp. 47-51 ◽  
Author(s):  
D. F. Evered ◽  
F. Sadoogh-Abasian
Keyword(s):  
Small Intestine ◽  
Calcium Ions ◽  
Clinical Evidence ◽  
Buccal Cavity ◽  
Rat Small Intestine ◽  
Sodium Ions ◽  
Mode Of Transport ◽  
Poor Absorption

1. The disaccharide lactulose (galactosyl-β-1,4-fructose) was poorly absorbed from rat small intestine in vitro and human mouth in vivo.2. These results confirm indirect clinical evidence of poor absorption from the intestine.3. The presence of calcium ions, or absence of sodium ions, had no effect on lactulose absorption from the buccal cavity.4. The presence of ouabain, or absence of Na+, did not decrease the absorption of lactulose from small intestine.5. It is thought that the mode of transport, in both instances, is by passive diffusion with the concentration gradient.

scholarly journals Porcine Milk-Derived Small Extracellular Vesicles Promote Intestinal Immunoglobulin Production through pIgR

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1522
Author(s):  
Bin Zeng ◽  
Hailong Wang ◽  
Junyi Luo ◽  
Meiying Xie ◽  
Zhengjiang Zhao ◽  
...  
Keyword(s):  
Small Intestine ◽  
Extracellular Vesicles ◽  
Immunoglobulin A ◽  
Luciferase Reporter ◽  
Epithelial Cell Line ◽  
Intestinal Immunity ◽  
In Vivo Experiments ◽  
Porcine Milk

Secretory immunoglobulin A (SIgA) plays an important role in gut acquired immunity and mucosal homeostasis. Breast milk is the irreplaceable nutritional source for mammals after birth. Current studies have shown the potential functional role of milk-derived small extracellular vesicles (sEVs) and their RNAs cargo in intestinal health and immune regulation. However, there is a lack of studies to demonstrate how milk-derived sEVs affect intestinal immunity in recipient. In this study, through in vivo experiments, we found that porcine milk small extracellular vesicles (PM-sEVs) promoted intestinal SIgA levels, and increased the expression levels of polymeric immunoglobulin receptor (pIgR) both in mice and piglet. We examined the mechanism of how PM-sEVs increased the expression level of pIgR in vitro by using a porcine small intestine epithelial cell line (IPEC-J2). Through bioinformatics analysis, dual-luciferase reporter assays, and overexpression or knockdown of the corresponding non-coding RNAs, we identified circ-XPO4 in PM-sEVs as a crucial circRNA, which leads to the expression of pIgR via the suppression of miR-221-5p in intestinal cells. Importantly, we also observed that oral administration of PM-sEVs increased the level of circ-XPO4 and decreased the level of miR-221-5p in small intestine of piglets, indicating that circRNAs in milk-derived sEVs act as sponge for miRNAs in recipients. This study, for the first time, reveals that PM-sEVs have a capacity to stimulate intestinal SIgA production by delivering circRNAs to receptors and sponging the recipient’s original miRNAs, and also provides valuable data for insight into the role and mechanism of animal milk sEVs in intestinal immunity.

Sign in / Sign up

Export Citation Format

Share Document