scholarly journals Fabrication of self‐assembled (‐)‐epigallocatechin gallate (EGCG) ovalbumin‐dextran conjugate nanoparticles and their transport across monolayers of human intestinal epithelial Caco‐2 cells (1044.1)

2014 ◽  
Vol 28 (S1) ◽  
Author(s):  
Zheng Li ◽  
Liwei Gu
2019 ◽  
Vol 2 (2) ◽  
pp. 96-101
Author(s):  
Kota Noda ◽  
Eisuke Kato ◽  
Jun Kawabata

Diabetes is a chronic disease characterized by elevated blood glucose level.Reducing carbohydrate absorption from the intestinal tract is an effective strategy to control post-meal blood glucose level. Inhibition of intestinal α-glucosidase, involved in digestion of carbohydrates, is known as an approach to accomplish this. On the other hand, reduction of α-glucosidase amount is expected to work in the similar manner. However, none of the previousstudy pursues this approach. A convenient assay was developed to evaluate α-glucosidase amount employing Caco-2 cells, the intestinal epithelial cell model reported to express α-glucosidase. Sixty plants were screened and two candidate plants, Calluna vulgaris and Perilla frutescens var. crispa were found to reduce α-glucosidase expression. C. vulgaris extract was subjected to activity guided isolation. Proanthocyanidin was identified as the active principle which was analyzed by thiol decomposition to reveal the components as a mixture ofcatechin, epicatechin, epigallocatechin, and A type procyanidin dimer. The proanthocyanidin suppressed about 30% of α-glucosidase amount evaluated through convenient assay, and suppressed bulk of mRNA expression level of sucrase-isomaltase (SI) at 0.125 mg/mL. Several flavan-3-ol monomers were also tested, and epicatechin gallate and epigallocatechin gallate were found to suppress α-glucosidase amount significantly.


2016 ◽  
Vol 145 ◽  
pp. 643-652 ◽  
Author(s):  
Jing Tian ◽  
Hu Tu ◽  
Xiaowen Shi ◽  
Xiaoying Wang ◽  
Hongbing Deng ◽  
...  

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 555 ◽  
Author(s):  
Pei Zhang ◽  
Shirui Zhao ◽  
Yaoyao Yu ◽  
Huan Wang ◽  
Yan Yang ◽  
...  

Polymeric nanoparticles could offer promising controlled drug delivery. The biocompatibility is of extreme importance for future applications in humans. Self-assembled polymeric nanoparticles based on phenylalanine ethyl ester (PAE)-modified alginate (Alg) had been successfully prepared and characterized in our lab. However, little is known about their interaction with cells and other biological systems. In this study, nanoparticles (NPs) based on PAE-Alg conjugates (PEA-NPs) with different degree of substitution (DS) were prepared and investigated. Our results showed that PEA-NPs had no effects on the proliferation of the human intestinal epithelial Caco-2 cells at concentrations up to 1000 μg/mL. Furthermore, the in vitro cellular uptake profile of PEA-NPs, concerning several parameters involved in the application of therapeutic or diagnostic NPs, such as NPs concentration, time and temperature, was described. Different NPs have been adopted for cellular uptake studies and the NPs internalized into Caco-2 cells were quantified. Cellular uptake efficiency could reach 60% within 4 h. PEA-NPs also showed greater cell permeability than oleoyl alginate ester nanoparticles (OAE-NPs) previously prepared in our lab. Our studies reveal that NPs based on PEA conjugate are promising nanosystems for cellular delivery.


Author(s):  
Patricia L. Jansma

The presence of the membrane bound vesicles or blebs on the intestinal epithelial cells has been demonstrated in a variety of vertebrates such as chicks, piglets, hamsters, and humans. The only invertebrates shown to have these microvillar blebs are two species of f1ies. While investigating the digestive processes of the freshwater microcrustacean, Daphnia magna, the presence of these microvillar blebs was noticed.Daphnia magna fed in a suspension of axenically grown green alga, Chlamydomonas reinhardii for one hour were narcotized with CO2 saturated water. The intestinal tracts were excised in 2% glutaraldehyde in 0.2 M cacodyl ate buffer and then placed in fresh 2% glutaraldehyde for one hour. After rinsing in 0.1 M cacodylate buffer, the sample was postfixed in 2% OsO4, dehydrated with a graded ethanol series, infiltrated and embedded with Epon-Araldite. Thin sections were stained with uranyl acetate and Reynolds lead citrate before viewing with the Philips EM 200.


Author(s):  
D.S. Friend ◽  
N. Ghildyal ◽  
M.F. Gurish ◽  
K.F. Austen ◽  
R.L. Stevens

Trichinella spiralis induces a profound mastocytosis and eosinophilia in the small intestine of the infected mouse. Mouse mast cells (MC) store in their granules various combinations of at least five chymotryptic chymases [designated mouse MC protease (mMCP) 1 to 5], two tryptic proteases designated mMCP-6 and mMCP-7 and an exopeptidase, carboxypeptidase A (mMC-CPA). Using antipeptide, protease -specific antibodies to these MC granule proteases, immunohistochemistry was done to determine the distribution, number and protease phenotype of the MCs in the small intestine and spleen 10 to >60 days after Trichinella infection of BALB/c and C3H mice. TEM was performed to evaluate the granule morphology of the MCs between intestinal epithelial cells and in the lamina propria (mucosal MCs) and in the submucosa, muscle and serosa of the intestine (submucosal MCs).As noted in the table below, the number of submucosal MCs remained constant throughout the study. In contrast, on day 14, the number of MCs in the mucosa increased ~25 fold. Increased numbers of MCs were observed between epithelial cells in the mucosal crypts, in the lamina propria and to a lesser extent, between epithelial cells of the intestinal villi.


Author(s):  
Julian P. Heath ◽  
Buford L. Nichols ◽  
László G. Kömüves

The newborn pig intestine is adapted for the rapid and efficient absorption of nutrients from colostrum. In enterocytes, colostral proteins are taken up into an apical endocytotic complex of channels that transports them to target organelles or to the basal surface for release into the circulation. The apical endocytotic complex of tubules and vesicles clearly is a major intersection in the routes taken by vesicles trafficking to and from the Golgi, lysosomes, and the apical and basolateral cell surfaces.Jejunal tissues were taken from piglets suckled for up to 6 hours and prepared for electron microscopy and immunocytochemistry as previously described.


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