Bioavailability and Speciation of Mineral Micronutrients: The Enzymolysis Approach

1997 ◽  
Vol 80 (4) ◽  
pp. 920-927 ◽  
Author(s):  
Pierre Hocquellet ◽  
Marie-Dominique L'Hotellier
Keyword(s):  
Gastrointestinal Tract ◽  
Absorption Spectrometry ◽  
Insoluble Residue ◽  
In Vivo Experiments ◽  
Treatment Data ◽  
Dietary Components ◽  
Vitro Model ◽  
Good Agreement

Abstract Speciation analyses are essential to investigate the effects of dietary components on bioavailability of mineral micronutrients. Enzymolysis was used. An in vitro model simulating enzymatic activity in the gastrointestinal tract of monogastric species was developed and used to assess availability of Fe, Cu, Mn, and Zn in some foodstuffs. The solubility of each element in samples was measured by atomic absorption spectrometry after enzymatic treatment. Data are in good agreement with information obtained from earlier, more expensive nutritional surveys or in vivo experiments and, therefore, allow prediction of the tendency of a particular food to induce mineral deficiency. In addition, ligands responsible for inhibiting intestinal absorption were identified by determining the amount of metal released after treatment of the insoluble residue with an appropriate enzyme such as cellulase and phytase, used respectively to study fiber and phytate interactions. Enzymolysis may be useful for optimizing mineral supplementations though its nutritional significance is somewhat limited by the fact that it does not take into account the dynamic changes in the gastrointestinal tract. Enzymolysis is a prerequisite for further speciation studies of complex systems and in some instances is the only way for specifying physicochemical forms of elements.

Food supplement “carrageenan” and its effect on the organism

2020 ◽  
Author(s):  
O.E. Luneva ◽  
Keyword(s):  
Gastrointestinal Tract ◽  
Food Additives ◽  
Food Supplement ◽  
The Body ◽  
Laboratory Rats ◽  
Experimental Part ◽  
In Vivo Experiments ◽  
Physiological Processes

Food additives are positioned as harmless, although, their components affectthe physiological processes associated with the permeability of the wall of the gastrointestinal tract (GIT) and intestinal microbiota. This article describes thecarrageenan supplement and its effects on the body in in vitro and in vivo experiments. The experimental part is devoted to analysis of the intestinalmicrobiota of laboratory rats with the consumption of the carrageenan dietary supplement in the amount of about 4,4 % of the standard feed.

Transfer of antibiotic resistance determinants between lactobacilli isolates from the gastrointestinal tract of chicken

2012 ◽  
Vol 3 (2) ◽  
pp. 137-144 ◽  
Author(s):  
F. Vieira de Souza ◽  
R. Roque ◽  
J.L. Silva Moreira ◽  
M. Resende de Souza ◽  
J.R. Nicoli ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Gastrointestinal Tract ◽  
Broiler Chickens ◽  
Lactobacillus Reuteri ◽  
Multi Drug Resistance ◽  
Bacterial Strains ◽  
Genetic Traits ◽  
In Vivo Experiments

The aim of this study was to assess the potential horizontal transfer of genetic traits for antibiotic resistance between lactobacilli isolated from the chicken gut, both in vitro and in vivo. Thirty-seven Lactobacillus spp. strains isolated from the gizzard, small and large intestines and caeca of free-range broiler chickens showed multi-drug resistance as assessed by disc diffusion assays. The minimum inhibitory concentration (MIC) for vancomycin, tetracycline, erythromycin and chloramphenicol was determined in De Man, Rogosa and Sharpe broth in a microplate assay. Almost all the lactobacilli isolates were resistant to vancomycin (except strains belonging to the Lactobacillus acidophilus group) and to tetracycline (MIC≥128 μg/ml). Only five strains were resistant to erythromycin, and six to chloramphenicol. The transfer rate in filter mating experiments performed using L. acidophilus strain 4M14E (EmR), Lactobacillus vaginalis strain 5M14E (CmR), Lactobacillus salivarius strain 5C14C (EmR), and the 4G14L and 3C14C strains of Lactobacillus reuteri (CmR) showed a frequency of approximately 1×104 cfu/ml of double-resistant transconjugants for the different combinations. The exception was the L. salivarius 5C14C (EmR) and L. vaginalis 5M14E (CmR) mating combination, which produced no transconjugants. In vivo experiments performed in gnotobiotic mice by mating L. acidophilus 4M14E (EmR) with L. reuteri 3C14C (CmR), L. reuteri 4G14L (CmR) or L. vaginalis 5M14E (CmR) resulted in transconjugants at 3.95±0.29, 3.16±0.33, and 4.55±1.52 log10 cfu/g of faeces, respectively. Taken together, these data suggest that genetic exchange may occur between native bacterial strains within the gastrointestinal tract of chickens, which might maintain a dynamic gene pool conferring antibiotic resistance upon indigenous microbiota components, even in the absence of the pathogens. This possibility must be taken into account as a complementary criterion when lactobacilli are screened for probiotic use.

scholarly journals In Vitro and In Vivo Study of the Gastrointestinal Absorption and Metabolisation of Hymenocardine, a Cyclopeptide Alkaloid

Planta Medica ◽  
2017 ◽  
Vol 83 (09) ◽  
pp. 790-796 ◽  
Author(s):  
Emmy Tuenter ◽  
Sebastiaan Bijttebier ◽  
Kenn Foubert ◽  
Annelies Breynaert ◽  
Sandra Apers ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Rat Plasma ◽  
In Vivo Study ◽  
Root Bark ◽  
In Vivo Experiments ◽  
Cyclopeptide Alkaloid ◽  
Blood And Urine Samples ◽  
The Stability

AbstractHymenocardine is a cyclopeptide alkaloid present in the root bark of Hymenocardia acida. In traditional African medicine, the leaves and roots of this plant are used to treat malaria, and moderate in vitro antiplasmodial activity has been reported for hymenocardine. However, in view of its peptide-like nature, potential metabolisation after oral ingestion has to be taken into account when considering in vivo experiments. In this study, the stability and small intestinal absorption of hymenocardine was assessed using an in vitro gastrointestinal dialysis model. In addition, potential liver metabolisation was investigated in vitro by incubation with a human S9 fraction. Moreover, hymenocardine was administered to rats per os, and blood and urine samples were collected until 48 and 24 h after oral administration, respectively. All samples resulting from these three experiments were analyzed by LC-MS. Analysis of the dialysate and retentate, obtained from the gastrointestinal dialysis model, indicated that hymenocardine is absorbed unchanged from the gastrointestinal tract, at least in part. After S9 metabolisation, several metabolites of hymenocardine could be identified, the major ones being formed by the reduction and/or the loss of an N-methyl group. The in vivo study confirmed that hymenocardine is absorbed from the gastrointestinal tract unchanged, since it could be identified in both rat plasma and urine, together with hymenocardinol, its reduction product.

scholarly journals SOX9 in prostate cancer is upregulated by cancer-associated fibroblasts to promote tumor progression through HGF/c-Met-FRA1 signaling

2020 ◽  
Author(s):  
Haixiang Qin ◽  
Yang Yang ◽  
Bo Jiang ◽  
Chun Pan ◽  
Wei Chen ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Tumor Progression ◽  
Molecular Mechanism ◽  
The Cancer Genome Atlas ◽  
Cancer Associated Fibroblasts ◽  
Sox9 Expression ◽  
In Vivo Experiments ◽  
Vitro Model

Abstract Background Previous studies have demonstrated that transcription factor SOX9 which was reactivated in prostate cancer (Pca) and promoted tumor growth was a poor prognostic biomarker for Pca. Nevertheless, the regulatory mechanism underlying SOX9 upregulation in Pca still remains unclear. Several cytokines widely distributed in the tumor microenvironment (TME) have been reported to be involved in the regulation of SOX9, suggesting that cancer-associated fibroblasts (CAFs), one of the main sources of secreted factors in TME, may play a role in regulating SOX9 expression. Methods Herein, an in vitro model of paracrine interaction between primary CAFs and Pca cells (both AR-positive and AR-negative Pca cells), was applied to investigate the molecular mechanism of SOX9 upregulation during Pca progression. The regulatory axis was validated by in vivo experiments and The Cancer Genome Atlas (TCGA) data. Results Conditional medium from Pca CAFs (CAF-CM) upregulated the expression of SOX9, which was also proved to be essential for CAF-induced tumor progression. Further analysis showed that it was hepatocyte growth factor (HGF) secreted by CAFs that was responsible for the SOX9 elevation in Pca cells via activating c-Met signaling. Mechanistically, HGF/c-Met signaling specifically activated MEK1/2-ERK1/2 pathway which then induced phosphorylated status and protein upregulation of FRA1. Furthermore, ChIP assay demonstrated that FRA1 transcriptionally upregulated SOX9 expression by binding to the TPA-responsive element (TRE) sequence in the promoter of SOX9 gene. We also found that HGF/c-Met-ERK1/2-FRA1-SOX9 axis was relatively conserved in human and mouse species by validating in mouse Pca cells (RM-1). Conclusions Our results revealed a novel insight into the molecular mechanism that SOX9 expression in Pca cells is promoted by CAFs, through the HGF/cMet-ERK1/2-FRA1 axis. Besides, SOX9 may serve as an alternative marker for the activated HGF/c-Met signaling to enroll the optimal Pca patients for HGF/c-Met inhibition treatment, since it is much more stable and easier to detect.

scholarly journals Changes of Neuropathy Target Esterase Affect Phospholipid Homeostasis in SK-N-SH Cells

2020 ◽  
Vol 71 (8) ◽  
pp. 327-334
Author(s):  
Li Yu-Yuan ◽  
Wu Yi-Jun
Keyword(s):  
In Vitro Model ◽  
Organophosphorus Compounds ◽  
Cell Model ◽  
Neuropathy Target Esterase ◽  
Phosphatidyl Glycerol ◽  
In Vivo Experiments ◽  
Vitro Model

Neuropathy target esterase (NTE), is a membrane protein located in the endoplasmic reticulum (ER). NTE has the activity of phospholipase B and can catalyze the deacylation of phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) to glycerylcholine (GPC). It is phosphorylated and aged by organophosphorus compounds (OPs), that induce delayed neuropathy in humans and sensitive animals. Our previous study has reported that the disruption of ER phospholipid homeostasis caused by the NTE inhibition may contribute to the initiation of the organophosphate-induced delayed neurotoxicity (OPIDN), while it is unknown how the disturbed phospholipid homeostasis initiates OPIDN. It is difficult to change phospholipids in in vivo experiments. Therefore, an in vitro model is urgently needed to explain the role of phospholipid homeostasis disorders in OPIDN. In this study, we altered the expression of NTE in SK-N-SH cells and determined its phospholipid component by using HPLC-MS. Our results showed that the changes of NTE affected the levels of PC, sphingomyelin (SM), phosphatidylethanolamine (PE), phosphatidylserine (PS), lysophosphatidylserine (LPS), phosphatidyl-glycerol (PG), and phosphatidylinositol (PI). Our results were consistent with the in vivo results. Furthermore, our findings indicate that the SK-N-SH cell model is a significantly useful method for the further research on how the changes of phospholipid homeostasis initiate the OPIDN, which is easier than the in vivo experiments in practice.

scholarly journals Endoworm: A new semi-autonomous enteroscopy device

2018 ◽  
Vol 232 (11) ◽  
pp. 1137-1143 ◽  
Author(s):  
Carlos Sánchez-Diaz ◽  
Esther Senent-Cardona ◽  
Vicente Pons-Beltran ◽  
Alberto Santonja-Gimeno ◽  
Ana Vidaurre
Keyword(s):  
Ex Vivo ◽  
Control Unit ◽  
Medical Personnel ◽  
Polyester Urethane ◽  
Rigid Tube ◽  
In Vivo Experiments ◽  
In Vivo Animal Model ◽  
Vitro Model

Using enteroscopes with therapeutic capacity to explore the small intestine entails certain limitations, including long exploration times, patient discomfort, the need for sedation, a high percentage of incomplete explorations and a long learning curve. This article describes the advances and setbacks encountered in designing the new Endoworm enteroscopy system, a semi-autonomous device consisting of a control unit and three cavities that inflate and deflate in such a way that the bowel retracts over the endoscope. The system can be adapted to any commercial enteroscope. Endoworm was tested in different intestine models: a polymethyl methacrylate rigid tube, an in vitro polyester urethane model, an ex vivo pig model and an in vivo animal model. The general behavior of the prototype was evaluated by experienced medical personnel. The mean distance covered through the lumen was measured in each cycle. The system was found to have excellent performance in the rigid tube and in the in vitro model. The ex vivo tests showed that the behavior depended largely on the mechanical properties of the lumen, while the in vivo experiments suggest that the device will require further modifications to improve its performance.

ANTITUMOR EFFECT OF COLLOIDAL SILVER BISILICATE IN EXPERIMENTAL IN VITRO AND IN VIVO STUDIES

2019 ◽  
Vol 65 (5) ◽  
pp. 760-765
Author(s):  
Margarita Tyndyk ◽  
Irina Popovich ◽  
A. Malek ◽  
R. Samsonov ◽  
N. Germanov ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Tumor Growth ◽  
Tumor Cells ◽  
Human Tumor ◽  
Significant Inhibition ◽  
In Vivo Studies ◽  
Ehrlich Carcinoma ◽  
In Vivo Experiments

The paper presents the results of the research on the antitumor activity of a new drug - atomic clusters of silver (ACS), the colloidal solution of nanostructured silver bisilicate Ag6Si2O7 with particles size of 1-2 nm in deionized water. In vitro studies to evaluate the effect of various ACS concentrations in human tumor cells cultures (breast cancer, colon carcinoma and prostate cancer) were conducted. The highest antitumor activity of ACS was observed in dilutions from 2.7 mg/l to 5.1 mg/l, resulting in the death of tumor cells in all studied cell cultures. In vivo experiments on transplanted Ehrlich carcinoma model in mice consuming 0.75 mg/kg ACS with drinking water revealed significant inhibition of tumor growth since the 14th day of experiment (maximally by 52% on the 28th day, p < 0.05) in comparison with control. Subcutaneous injections of 2.5 mg/kg ACS inhibited Ehrlich's tumor growth on the 7th and 10th days of the experiment (p < 0.05) as compared to control.

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