• The Korean Journal of Physiology and Pharmacology
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• 제2권4호
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• pp.521-527
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• 1998

An important property of the intestine is the ability to secrete fluid. The intestinal secretion is regulated by a number of substances including vasoactive intestinal peptide (VIP), ATP and different inflammatory mediators. One of the most important secretagogues is adenosine during inflammation. However, the controversy concerning the underlying mechanism of adenosine-stimulated $Cl^-$ secretion in intestinal epithelial cells still continues. To investigate the effect of adenosine on $Cl^-$ secretion and its underlying mechanism in the rabbit colon mucosa, we measured short circuit current ($I_{SC}$) under automatic voltage clamp with DVC-1000 in a modified Ussing chamber. Adenosine, when added to the basolateral side of the muocsa, increased $I_{SC}$ in a dose-dependent manner. The adenosine-stimulated $I_{SC}$ response was abolished when $Cl^-$ in the bath solution was replaced completely with gluconate. In addition, the $I_{SC}$ response was inhibited by a basolateral Na-K-Cl cotransporter blocker, bumetanide, and by apical $Cl^-$ channel blockers, dephenylamine-2-carboxylate (DPC), 5-nitro-2-(3-phenyl-propylamino)-benzoate (NPPB), glibenclamide. Amiloride, an epithelial $Na^+$ channel blocker, and 4,4-diisothiocyanato-stilbene-2,2-disulphonate (DIDS), a $Ca^{2+}-activated$ $Cl^-$ channel blocker, had no effect. In the mucosa pre-stimulated with forskolin, adenosine did not show any additive effect, whereas carbachol resulted in a synergistic potentiation of the $I_{SC}$ response. The adenosine response was inhibited by 10 ${\mu}M$ H-89, an inhibitor of protein kinase A. These results suggest that the adenosine-stimulated $I_{SC}$ response is mediated by basolateral to apical $Cl^-$ secretion through a cAMP-dependent $Cl^-$ channel. The rank order of potencies of adenosine receptor agonists was $5'-(N-ethylcarboxamino)adenosine(NECA)＞N^6-(R-phenylisopropyl)adenosine(R-$ PIA)＞2-[p-(2-carbonylethyl)-phenyl-ethylamino]-5'-N-ethylcarboxaminoadenosine(CGS21680). From the above results, it can be concluded that adenosine interacts with the $A_{2b}$ adenosine receptor in the rabbit colon mucosa and a cAMP-dependent signalling mechanism underlies the stimulation of $Cl^-$ secretion.

• 한국동물학회지
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• 제17권2호
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• pp.69-80
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• 1974

동면 전, 중, 후 및 활동기간 동안 옴개구리(Rana rugosa)의 위장관 점액분비세포내 점액성 물질의 변화를 조직화학적으로 관찰하여 다음과 같은 결론을 얻었다. 1. 옴개구리의 위장관 점막내 점액성 물질은 위 표면상피세포에서 PAS에, 소장 배상 세포에서는 PAS와 AB 2.5에, 그리고 대장 배상세포에서는 AB 2.5에 강한 양성 반응을 보였다. 2. 동면에 따라 위 점막분비세포내 PAS 양성인 중성 점액질은 현저히 증가하였다. 3. 동면에 따라 소장내 AB 2.5에 양성인 약산성 점액질과 AB 1.0에 양성인 산성 유화 점액질은 현저히 감소를 보이는 반면, PAS 양성인 중성 점액질은 약간 증가를 보였다. 4. 동면에 따라 대장내 AB 2.5에 양성인 약산성 점액질은 아주 현저한 감소를 보였고, PAS양성인 중성 점액질도 역시 다소 감소를 보였다. 5. 동면시 위점막 상피세포내에서 PAS양성인 점액질은 그 분비능이 합성능에 미치지 못하여 현저히 증가되며, 위 점막의 접착을 방지하고, 위산 및 효소의 활성을 억제하는 것으로 생각되며, 장내 배상세포에서는 위산 및 장액분비의 현저한 감소로 장내 산도가 중성에 가까워져서 중성에 가까운 점액물질을 분비하는 것으로 추리된다.

• Gut and Liver
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• 제12권6호
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• pp.682-693
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• 2018

Background/Aims: Intestinal barrier dysfunction is a hallmark of inflammatory bowel diseases (IBDs) such as ulcerative colitis. This dysfunction is caused by increased permeability and the loss of tight junctions in intestinal epithelial cells. The aim of this study was to investigate whether estradiol treatment reduces colonic permeability, tight junction disruption, and inflammation in an azoxymethane (AOM)/dextran sodium sulfate (DSS) colon cancer mouse model. Methods: The effects of $17{\beta}$-estradiol (E2) were evaluated in ICR male mice 4 weeks after AOM/DSS treatment. Histological damage was scored by hematoxylin and eosin staining and the levels of the colonic mucosal cytokine myeloperoxidase (MPO) were assessed by enzyme-linked immunosorbent assay (ELISA). To evaluate the effects of E2 on intestinal permeability, tight junctions, and inflammation, we performed quantitative real-time polymerase chain reaction and Western blot analysis. Furthermore, the expression levels of mucin 2 (MUC2) and mucin 4 (MUC4) were measured as target genes for intestinal permeability, whereas zonula occludens 1 (ZO-1), occludin (OCLN), and claudin 4 (CLDN4) served as target genes for the tight junctions. Results: The colitis-mediated induced damage score and MPO activity were reduced by E2 treatment (p<0.05). In addition, the mRNA expression levels of intestinal barrier-related molecules (i.e., MUC2, ZO-1, OCLN, and CLDN4) were decreased by AOM/DSS-treatment; furthermore, this inhibition was rescued by E2 supplementation. The mRNA and protein expression of inflammation-related genes (i.e., KLF4, NF-${\kappa}B$, iNOS, and COX-2) was increased by AOM/DSS-treatment and ameliorated by E2. Conclusions: E2 acts through the estrogen receptor ${\beta}$ signaling pathway to elicit anti-inflammatory effects on intestinal barrier by inducing the expression of MUC2 and tight junction molecules and inhibiting pro-inflammatory cytokines.

• BMB Reports
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• 제53권9호
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• pp.478-483
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• 2020

Kudoa septempunctata is a myxozoan parasite that causes food poisoning in individuals consuming olive flounder. The present study aimed to investigate the currently insufficiently elucidated early molecular mechanisms of inflammatory responses in the intestine owing to parasite ingestion. After Kudoa spores were isolated from olive flounder, HT29 cells were exposed to spores identified to be alive using SYTO-9 and propidium iodide staining or to antigens of Kudoa spores (KsAg). IL-1β, IL-8, TNF-α and NFKB1 expression and NF-κB activation were assessed using real-time PCR, cytokine array and western blotting. The immunofluorescence of FITC-conjugated lectins, results of ligand binding assays using Mincle-Fc and IgG-Fc, CLEC4E expressions in response to KsAg stimulation, and Mincle-dependent NF-κB activation were assessed to clarify the early immune-triggering mechanism. Inflammatory cytokines (IL-1β, GM-CSF and TNF-α), chemokines (IL-8, CCL2, CCL5 and CXCL1) and NF-κB activation (pNF-κB/NF-κB) in HT29 cells increased following stimulation by KsAg. The immunofluorescence results of spores and lectins (concanavalin A and wheat germ agglutinin) suggested the importance of Mincle in molecular recognition between Kudoa spores and intestinal cells. Practically, data for Mincle-Fc and KsAg binding affinity, CLEC4E mRNA expression, Mincle immunofluorescence staining and hMincle-dependent NF-κB activation demonstrated the involvement of Mincle in the early immune-triggering mechanism. The present study newly elucidated that the molecular recognition and immune-triggering mechanism of K. septempunctata are associated with Mincle on human intestinal epithelial cells.

• 대한수의학회지
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• 제39권3호
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• pp.425-434
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• 1999

The morphological studies on the cecal development in the 60-, 90-, and 120-day-old fetuses and the newborns of Korean native goats were investigated by scanning and transmission electron microscopy. The results were summarized as follows ; Scanning electron microscopic studies : 1. In the 60-day-old fetuses, fold-like shapes protrusion on the cecal mucosa surface appeared. In the 90-day-old fetuses, the cecal villi appeared to be columnar shapes. In the 120-day-old fetuses, the cecal villi showed various tongue-like or columnar shapes. In the newborns, only the rudimental trace of the villi and the intestinal glands were observed. Transmission electron microscopic studies : 2. In the 60-day-old fetuses, the cecal epithelia were simple columnar in some areas and stratified columnar in others, and the epithelial cells contained nuclei, nucleoli, ER, mitochondria, Golgi complexes, zonula occludens, desmosomes, digitiform intercellular junctions, and large masses of the glycogen granules. 3. In the 90-day-old fetuses, the cecal epithelia were simple columnar in some area and stratified columnar in other. The microvilli of the cecal epithelia became much larger and longer than those in the 60-day-old fetuses, and intercellular junctions were developed, and increased numbers of ER, mitochondria, Golgi complexes were observed and the goblet cells contained a lot of the secretory granules. 4. In the 120-day-old fetuses, the cecal epithelia were only simple columnar in all areas. Microvilli and cytoplasmic organelles were well developed and the irregular annular nuclei were observed. 5. In the newborns, the cecal epithelia were covered with extensive microvilli, and the goblet cells with secretory granules were protruded into the lumen. And some goblet cells secreted the secretory granules into the lumen.

• 생명과학회지
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• 제17권1호
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• pp.110-115
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• 2007

Tumor suppressor 유전자로알려진 early growth response gene 1 (EGR-1)에 있어 항산화 천연물인 apigenin과 그대사물인 isovitexin에 의한 장관 상피성 종양세포에 대하여 항종양 역할을 규명하였다. Apigenin 과 isovitexin은 대장암세포에서의 EGR-1 단백질의 발현을 9-12시간의 노출에 의해 농도 의존적으로 증가하였다. 또한 신호전달측면에서 이런 apigenin에 의한 EGR-1 유전자의 유도가 U0126 화합물에 의해 완벽하게 저해 받는 것으로 보아 ERK1/2 MAP kinase pathway의 이 신호전달계에서의 관여를 보여주었다. 본 연구에서 apigenin에 의해 농도 의존적으로 대장암세포의 세포활성의 저해를 MTT assay를 통해 보였고, 또한 EGR-1 siRNA를 transfectien한 세포의 경우 이런 apigenin에 의한 세포활성의 저해효과를 완화하였다. 따라서 apigenin에 의한 항종암세포 세포활성 억제에 있어 EGR-1의 중요성을 보여 준다. 이런 EGR-1에 의해 유도되는 유전자중 대표적으로 NAG-1 유전자의 경우 apigenin과 isovitexin에 의해 24-48시간에 발현이 증가하였다. 결론적으로 암세포 증식억제활성이 있고 apoptosis 유도효과가 있는 NAG-1의 유도에 의해 대장암 세포의 세포활성이 억제된 것으로 의미되고 향후 apigenin 유도의 NAG-1유전자에 의한 암세포증식의 억제기전에 대한 명확한 연구가 요구된다.

• Parasites, Hosts and Diseases
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• 제28권1호
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• pp.45-52
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• 1990

인체 기생 장흡충류의 하나인 호르텐스극구흠충(Echinostoma hortense)의 병원성을 알아 보기 위하여 흰쥐에 퍼낭유충을 실험 감염시킨 후 경시적으로 숙주의 장병변을 관찰하였다. 피낭유충은 실험적으로 감염시킨 올챙이에서 분리한 것을 사용하였고 Sprague-Dawley계 흰쥐 18마리에 각각 200개씩 감염시킨 후 1일, 3일, 7일, 11일, 22일 및 44일에 3마리씩 희생시키고 위 유문으로부터 1cm, 3cm, 5cm, 8cm 및 30cm 부위에서 각각 장 절편을 채취하여 병리 조직학적 관찰을 시 행하였다. 관찰 결과 충체는 감염 1∼3일에는 융모 사이 (infervillous space)에서, 감염 7일부터 44일까지는 주로 내강(lumen)에서 발견되었고 구흡반 및 복흡반으로 융모를 흡입(sucking, 파괴하고 있는 것이 관찰되었다. 장 조직의 병변은 융모 위축(villous atrophy)과 선와 증식 (crypt hyperplasia)이 특징적 소견이었다. 융모의 변화는 끝(tip)의 둔화, 유착, 소실 등이었고 융모1선와 높이의 비율 이 3 : 1에서 1 : 1까지 감소되었다. 기질의 변화로는 염증 세포의 침윤, 충혈, 부종, 섬유화 등이 관 찰되었다. 배세포는 감염 11일 경부터 점차 증가하는 소견을 보였다. 전체적으로 장 병변은 소장 상 부에서 카장 심하였고 감염 1∼3일부터 관찰되기 시작하였으며 감염기간의 경과에 따라 점차 심화 되었다. 이상의 결과를 종합할 때 호르텐스극구흡충에 감염된 횐쥐의 장 병변은 점막층에 국한되어 있으나 융모의 위축 및 파괴가 매우 심하며 감염 44일까지도 병변이 지속되고 있음을 알 수 있었다. Key worths: Echinostoma hortense, rat intestinal pathology, villous atrophy, crypt hyperplasia로 출아묘는 이앙기간이 단축되므로 중묘보다는 다소 늦게 파종하고 이앙기는 중묘 적기에 하는 냉해의 우려도 없어 좋을 것으로 생각된다. 6. 간장은 중묘보다 어린모 이앙재배에서 3∼4cm 기었는데 이는 천식이 되어 초기생육이 왕성하므로 과번무 되었기 때문으로 생각되며 지나친 천식은 태풍 등으로 도복의 위험성이 있다. 7. 수량성은 조식재배의 경우 어린모는 중묘와 비슷한 경향이며 직파재배 보다 다소 증수되었다.질소함량은 경장, 건물중, 근류수 및 근류중들과, 그리고 줄기중의 allantoin 질소함량은 근류수 및 근류중들과 각각 유의적인 정의 상관관계를 나타내었다. 희미해졌으며 담배는 500 $\mu$ E m$^{-2}$ sec$^{-1}$에서 인삼은 1000 $\mu$ E m$^{-2}$ sec$^{-1}$에서 47KD이었다.50일영이상)에서 35.3％ 및 유추(30 일영미만)에서 17.3％의 순이었다. 이중 세균성 및 기생충성 질병은 육성계에서의 검색률이 가장 높았으나, 바이러스성 질병은 육성계 및 성계에서 거의 같은 비율로 높았으며 곰팡이성 질병은 유추에서 가장 높은 검색률을 나타내었다.17) 사료비절감은 생산비의 60∼70％를 차지하고 있으므로 공동구인 자가배합을 하여 자기실정에 맞는 경영체질로 운영하고 있었다. (18) 인건비가 생산비의 15∼20％의 비율이며 또한 사람 구득난이라 가족노동을 최대한 활용, 관리를 하고 있으며 생력화를 위해 기계화, 자동화되어 가고 있었다. 애정과 정성심있는 관리로 닭을 스트레스를 주지 않게 하기 위해 가족관이, 기계자동화가 중요한 역할을 하고 있었다. (19) 시설기구와 육성상각비를 줄이기 위해 관리자의 변동이 없고, 종신직장으로서 긍지와 자부심을 가지고 늑무하고 있었다.

• Journal of Microbiology and Biotechnology
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• 제25권9호
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• pp.1510-1518
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• 2015

In this work, we wanted to develop a probiotic from famous longevity villages in Korea. We visited eight longevity villages in Korea to collect fecal samples from healthy adults who were aged above 80 years and had regular bowel movements, and isolated lactic-acid-producing bacteria from the samples. Isolated colonies that appeared on MRS agar containing bromophenol blue were identified by means of 16S rRNA sequencing, and 102 of the isolates were identified as lactic-acid-producing bacteria (18 species). Lactobacillus fermentum was the most frequently found species. Eight isolates were selected on the basis of their ability to inhibit the growth of six intestinal pathogens (Escherichia coli O157:H7, Salmonella enterica subsp. enterica Typhimurium, Salmonella enterica subsp. enterica Enteritidis, Enterococcus faecalis, Staphylococcus aureus, and Listeria monocytogenes) and their susceptibility to 15 antimicrobial agents. Among these eight isolates, four Lactobacillus fermentum isolates were found not to produce any harmful enzymes or metabolites. Among them, Lactobacillus fermentum isolate no. 24 showed the strongest binding to intestinal epithelial cells, the highest immune-enhancing activity, anti-inflammation activity, and anti-oxidation activity as well as the highest survival rates in the presence of artificial gastric juice and bile solution. This isolate, designated Lactobacillus fermentum PL9988, has all the characteristics for a good probiotic.

• Clinical and Experimental Pediatrics
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• 제63권8호
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• pp.301-309
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• 2020

Human breast milk (HBM) is essential for the infant's growth and development right after birth and is an irreplaceable source of nutrition for early human survival. Various infant formulas have many similarities to HBM in many components, but there is no perfect substitute for HBM. Recently, various breast milk components and their roles have been studied according to the development of various analysis techniques. As is already well known, HBM contains about 87%-88% water, and 124-g/L solid components as macronutrients, including about 7% (60-70 g/L) carbohydrates, 1% (8-10 g/L) protein, and 3.8% (35-40 g/L) fat. The composition may vary depending on the environmental factors, including maternal diet. Colostrum is low in fat but high in protein and relatively rich in immuneprotective components. Although HBM contains enough vitamins to ensure normal growth of the infant, vitamins D and K may be insufficient, and the infant may require their supplementation. Growth factors in HBM also serve as various bioactive proteins and peptides on the intestinal tract, vasculature, nervous system, and endocrine system. In the past, HBM of a healthy mother was thought to be sterile. However, several subsequent studies have confirmed the presence of rich and diverse microbial communities in HBM. Some studies suggested that the genera Staphylococcus and Streptococcus may be universally predominant in HBM, but the origin of microbiota still remains controversial. Lastly, milk is the one of most abundant body fluid of microRNAs, which are known to play a role in various functions, such as immunoprotection and developmental programming, through delivering from HBM and absorption by intestinal epithelial cells. In conclusion, HBM is the most important source of nutrition for infants and includes microbiomes and miRNAs for growth, development, and immunity.

• ALGAE
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• 제35권2호
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• pp.201-212
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• 2020

The inflammatory bowel diseases (IBD) including ulcerative colitis and Crohn disease are characterized by chronic inflammation throughout the gastrointestinal tract. The prevalence of IBD has been increasing worldwide, and has sometimes led to irreversible impairment of gastrointestinal structure and functions. In the present study, we identified a new sulfoquinovosylmonoacylglycerols (SQMG) (1) together with two known SQMGs (2 and 3) regulating intestinal inflammation from the brown alga Turbinaria ornata. The anti-inflammatory properties of two bioactive SQMGs, 1 and 2 were evaluated using an in vitro co-culture system consisting of human epithelial Caco-2 cells and PMA (phorbol 12-myristate 12-acetate)-differentiated THP-1 macrophages. Treatment with 1 or 2 inhibited the production nitric oxide and prostaglandin E₂ induced by lipopolysaccharide and interferon γ challenge. The expressions of inducible nitric oxide synthase and cyclooxygenase 2 were markedly down-regulated in response to inhibition of nuclear factor κB translocation to nucleus. These findings suggest the potential use of the brown alga T. ornata and its biologically active metabolites SQMGs as pharmaceutical adjuvants in the treatment of inflammation-related diseases, including IBD.