• Archives of Pharmacal Research
• /
• v.29 no.4
• /
• pp.318-322
• /
• 2006

Many quaternary ammonium salts are incompletely absorbed after their oral administration and may also be actively secreted into the intestine. However, the underlying mechanism(s) that control the transport of these cations across the intestinal epithelium is not well understood. In this study, the mechanism of absorption of quaternary ammonium salts was investigated using Caco-2 cell monolayers, a human colon carcinoma cell line. Tributylmethylammonium (TBuMA) was used as a model quaternary ammonium salts. When TBuMA was administrated at a dose of 13.3 imole/kg via iv and oral routes, the AUC values were $783.7{\pm}43.6\;and\;249.1{\pm}28.0{\mu}mole\;min/L$ for iv and oral administration, indicating a lower oral bioavailability of TBuMA $(35.6\%)$. The apparent permeability across Caco-2 monolayers from the basal to the apical side was 1.3 times (p<0.05) greater than that from the apical to the basal side, indicating a net secretion of TBuMA in the intestine. This secretion appeared to be responsible for the low oral bioavailability of the compound, probably mediated by p-gp (p-glycoprotein) located in the apical membrane. In addition, the uptake of TBuMA by the apical membrane showed a $Na^+$ dependency. Thus, TBuMA appears to absorbed via a $Na^+$ dependent carrier and is then secreted via p-gp related carriers.

• Proceedings of the Korean Nutrition Society Conference
• /
• 1995.11b
• /
• pp.11-34
• /
• 1995

Growth hormone (GH) plays a key role in regulating postnatal growth and can stimulate growth of animals by acting directly on specific receptors on the plasma membrane of tissues or indirectly through stimulating insulin-like growth factor (IGF)-I synthesis and secretion by the liver and other tissues. IGF-I and IGF-Ⅱ are polypeptides with structural similarity with proinsulin that stimulate cell proliferation by endocrine, paracrine and autocrine mechanisms. The initial event in the metabolic action of IGFs on target cells appears to be their binding to specific receptors on the plasma membrane. Current evidence indicates that the mitogenic actions of both IGFs are mediated primarily by binding to the type I IGF receptors, and that IGF action is also mediated by interactions with IGF-binding proteins (IGFBPs). Six distinct IGFBPs have been identified that are characterized by cell-specific interaction, transcriptional and post-translational regulation by many different effectors, and the ability to either potentiate or inhibit IGF actions. Nutritional deficiencies can have their devastating consequence during growth. Although IGF-I is the major mediator of GH's action on somatic growth, nutritional status of an organism is a critical regulator of IGF-I and IGFBPs. Various nutrient deficiencies result in decreased serum IGF-I levels and altered IGFBP levels, but the blood levels of GH are generally unchanged or elevated in malnutrition. Effects of protein, energy, vitamin C and D, and zinc on serum IGF and IGFBP levels and tissue mRNA levels were reviewed in the text. Multiple factors are involved in the regulation of intestinal epithelial cell growth and differentiation. Among these factors the nutritional status of individuals is the most important. The intestinal epithelium is an important site for mitogenic action of the IGFs in vivo, with exogenous IGF-I stimulating mucosal hyperplasia. Therefore, the IGF system appears to provide and important mechanism linking nutrition and the proliferation of intestinal epithelial cells. In order to study the detailed mechanisms by which intestinal mucosa is regulated, we have utilized IEC-6 cells, an intestinal epithelial cell line and Caco-2 cells, a human colon adenocarcinoma cell line. Like intestinal crypt cells analyzed in vivo or freshly isolated intestinal epithelial cells, IEC-6 cells and Caco-2 cells possess abundant quatities of both type Ⅰ and type Ⅱ IGF receptors. Exogenous IGFs stimulate, whereas addition of IGFBP-2 inhibits IEC-6 cell proliferation. To investigate whether endogenously secreted IGFBP-2 inhibit proliferation, IEC-6 cells were transfected with a full-length rat IGFBP-2 cDNA anti-sense expression construct. IEC-6 cells transfected with anti-sense IGFBP-2 protein in medium. These cells grew at a rate faster than the control cells indicating that endogenous IGFBP-2 inhibits proliferation of IEC-6 cells, probably by sequestering IGFs. IEC-6 cells express many characteristics of enterocyte, but do not undergo differentiation. On the other hand, Caco-2 cells undergo a spontaneous enterocyte differentiation. On the other hand, Caco-2 cells undergo a spontaneous enterocyte differentiation after reaching confluency. We have demonstrated that Caco-2 cells produce IGF-Ⅱ, IGFBP-2, IGFBP-3, and an as yet unidentified 31,000 Mr IGFBP, and that both mRNA and peptide secretion of IGFBP-2 and IGFBP-3 increased, but IGFBP-4 mRNA and protein secretion decreased after the cells reached confluency. These changes occurred in parallel to and were coincident with differentiation of the cells, as measured by expression of sucrase-isomaltase. In addition, Caco-2 cell clones forced to overexpress IGFBP-4 by transfection with a rat IGFBP-4 cDNA construct exhibited a significantly slower growth rate under serum-free conditions and had increased expression of sucrase-isomaltase compared with vector control cells. These results indicate that IGFBP-4 inhibits proliferation and stimulates differentiation of Caco-2 cells, probably by inhibiting the mitogenic actions of IGFs.

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.234.3-235
• /
• 2003

The aim of this study is to evaluate the permeability of PEG-conjugated salmon calcitonin (sCT) across monolayers of Caco-2 cells that represent a model of the intestinal barrier. Caco-2 cells were grown to confluency on a permeable polycarbonate membrane to permit transport through it. Permeability experiments were performed with native-sCT and PEG-conjugated sCT (PEG M.W. 2000) at various concentrations (5uM, 10uM, 25uM, 50uM, 100uM) in the apical to basolateral direction. The barrier properties were assessed by detecting transport of markder molecules ($^3$H-mannitol) and by measuring transepithelial electrical resistance (TEER). (omitted)

• Microbiology and Biotechnology Letters
• /
• v.49 no.2
• /
• pp.157-166
• /
• 2021

The probiotic market is constantly continuing to grow, concomitantly with a widening in the range and diversity of probiotic products. Probiotics are defined as live microorganisms that provide a benefit to the host when consumed at a proper dose; the viability of a probiotic is therefore of crucial importance for its efficacy. Many products undergo lyophilization for maintaining their shelf-life. Unfortunately, this procedure may damage the integrity of the cells due to stress conditions during both the freezing and (vacuum-) drying process, thereby impacting their functionality. We propose a lysine-based mixture for rehydration of freeze-dried probiotics for improving their viability during in vitro simulated gastric and duodenum stress conditions. Measurement of the zeta potential served as an indicator of cell integrity and efficacy of this mixture, while functionality was estimated by adhesion to a human enterocyte-like Caco-2 cell-line. The freeze-dried bacteria exhibited a significantly different zeta potential compared to fresh cultures; however, this condition could be restored by rehydration with the lysine mixture. Recovery of the surface charge was found to influence adhesion ability to the Caco-2 cell-line. The optimum lysine concentration of the formulation, designated "Zeta-bio", was found to be 0.03 M for improving the viability of Lactiplantibacillus plantarum Lp-115 by up to 13.86% and a 7-strain mixture (400B) to 41.99% compared to the control rehydrated with distilled water. In addition, the lysine Zeta-bio formulation notably increased the adherence ability of lyophilized Lp-115 to the Caco-2 cell-line after subjected to the in vitro stress conditions of the simulated gastrointestinal tract passage.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.2
• /
• pp.217-222
• /
• 2003

We studied effects of hot water extract of Lentinus edodes (Berk.)sing. and Pleurotus eryngii (De Candolle ex Fries) Quel mushroom on proliferation and apoptosis of the human colon adenocarcinoma, HT-29 and Caco-2.. Cells were maintained with Dulbecco's modified Eagle medium/Ham's F-12 nutrient mixture supplemented with 10% fetal bovine serum at 37$^{\circ}C$ in a humidified $CO_2$. For cell proliferation experiments, cells were seeded in 35 mm dishes, treated with the various concentrations of the extract for the different time course. Apoptosis was measured by caspase-3 activity The more contents of the extract added in HT-29 and Caco-2 were, the more cell proliferation was suppressed. When we incubated HT-29 cells for 24, B\ulcorner72, and 96 hours after treatments, cell proliferation was markedly suppressed after 96 hours. Also, caspase-3 activity in HT-29 was increased by the treatment of Lentinus edodes and Pleurotus eryngii extracts. However, the treatment of the extract to SNU484, Korean stomach adenocarcinoma, did not show any influence on cell proliferation and caspase-3 activity Therefore, Lentinus edodes and Pleurotus eryngii are strongly recommended for the prevention and treatment of colon cancer.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.10
• /
• pp.1583-1587
• /
• 2015

Bile acids are endogenous metabolites that aid in the digestion and absorption of ingested fat and fat-soluble vitamins. However, high concentrations of deoxycholic acid (DCA) in the colon are associated with high incidence of colorectal cancer. In the present study, the binding of persimmon extracts to DCA in order to decrease inflammatory stress induced by DCA in a small intestinal epithelial cell line, Caco-2, was investigated. Young and ripened persimmons were extracted with distilled water (DW), ethanol, and acidic ethanol. Further, DW extract residue was re-extracted with acidic ethanol. Of the obtained extracts, acidic ethanol extract of young persimmon showed the highest bile-acid binding capacity. Moreover, acidic ethanol extract of young persimmon significantly inhibited nitric oxide production in Caco-2 cells stimulated with DCA and prevented significant reduction of trans-epithelial electric resistance. Based on these results, acidic ethanol extract of young persimmon can be used as a functional ingredient to enhance gastrointestinal health.

• Proceedings of the PSK Conference
• /
• 2001.04a
• /
• pp.108.2-109
• /
• 2001

• Environmental Analysis Health and Toxicology
• /
• v.22 no.1 s.56
• /
• pp.65-71
• /
• 2007

유산균(Lactic acid bacteria)은 Escherichia coli와 Salmonella typhimurium과 같은 병원균에 대한 항균활성을 나타낼 뿐만 아니라 면역 증강효과를 나타내는 등 인체내에서 건강에 이로운 다양한 역할을 수행하는 것으로 알려졌다. 특히, Pediococcus pentosaseus와 몇몇 Lactobacillus 종으로부터 분리한 항균활성을 나타내는 peptide들인 safelac과 lactopad는 몇몇 암세포주의 성장을 억제하는 것으로 나타났다. 이에, 본 연구에서는 HT-29, SW 480 및 Caco-2와 같은 3종류의 인간의 결장암 세포주에 safelac과 lactopad를 투여하여 이들이 항암효과를 나타낼 수 있는 지를 분석하고자 하였다. XTT assay는 safelaf과 lactopad가 HT-29, SW 480 및 Caco-2의 성장을 억제하는 것으로 나타났으며, 특히, 이들 peptide들을 72시간동안 처리했을 때 나타나는 항암효과는 $3.1{\sim}100mg/mL$의 농도범위에서 유의한 결과를 나타내었으며, 분석한 농도 범위에서 용량 의존적인 방식으로 더 강한 효과를 나타내었다. RAW 264.7 세포주는 cytokine인 tumor-necrosis factor(TNF-${\alpha}$)의 생성에 미치는 이들 peptide들의 효과를 조사하기 위한 대식세포의 모델로써 이용되었다. RAW 264.7 세포주에서 TNF-${\alpha}$의 생성은 이들 peptide들에 의해 48시간 배양시 용량에 의존적인 방식으로 영향을 받는 것으로 나타났다. 따라서, 이러한 발견은 safelac과 lactopad와 같은 유산균으로부터 분리한 항균 peptide들이 결장암 세포에 대한 화학적 예방제로서의 잠재성을 갖고 있음을 시사하는 결과로서 주목된다.

• 한국유가공학회:학술대회논문집
• /
• 2001.05a
• /
• pp.37-47
• /
• 2001

• The Journal of Internal Korean Medicine
• /
• v.22 no.3
• /
• pp.383-391
• /
• 2001

목적 : 본 연구는 목향순기탕(木香順氣湯)이 인간의 장관상피세포 계열인 Caco-2 세포에서 항산화작용을 증진시키는 효과가 있는지 검증하기 위한 실험이다. 방법 : 배양된 인간장관 세포계열인 Caco-2 세포에서 세포의 사망은 trypan blue의 소실정도에 의해 평가했으며 $H_2O_2$는 표본산화제로 사용되었다. 결과 : $H_2O_2$에서 노출된 세포들은 용량에 비례하여 세포 사망하는 결과를 보였다. 목향순기탕(木香順氣湯)은 $H_2O_2$에 의해 유발된 세포사망을 방지하였고, 0.05-1%의 농도범위에 걸쳐서 효과가 극대화되었다. 목향순기탕(木香順氣湯)과 강력한 항산화제인 DPPD는 $H_2O_2$에 의해 억제된 SOD의 활성에는 영향을 주지는 못했다. 그러나 $H_2O_2$에 의해 유발된 catalase, glutathione peroxidase, hydroperoxide 탈취효소의 활성이 감소되는 것을 억제하였다. 또한 $H_2O_2$에 의해 유발된 glutathione의 감소는 목향순기탕(木香順氣湯)과 DPPD에 의해 억제되었다. 목향순기탕(木香順氣湯)은 $H_2O_2$에 의해 유발된 ATP의 소실을 회복시켰지만 DPPD는 ATP 소실을 회복시키지 못하였다. 결론 : 이러한 결과로 볼 때 Caco-2세포에서 목향순기탕이 세포사망을 억제하는 것은 다른 기전을 통하여 항산화작용을 하는 것으로 볼 수 있다. 따라서 본 연구는 목향순기탕(木香順氣湯)이 반응성산소기에 의해 유발된 인체 위장관질환의 치료에 사용할 수 있을 가능성을 제시하고 있다.