• The Korean Journal of Physiology and Pharmacology
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• 제18권2호
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• pp.89-94
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• 2014

DA-6034, a eupatilin derivative of flavonoid, has shown potent effects on the protection of gastric mucosa and induced the increases in fluid and glycoprotein secretion in human and rat corneal and conjunctival cells, suggesting that it might be considered as a drug for the treatment of dry eye. However, whether DA-6034 induces $Ca^{2+}$ signaling and its underlying mechanism in epithelial cells are not known. In the present study, we investigated the mechanism for actions of DA-6034 in $Ca^{2+}$ signaling pathways of the epithelial cells (conjunctival and corneal cells) from human donor eyes and mouse salivary gland epithelial cells. DA-6034 activated $Ca^{2+}$-activated $Cl^-$ channels (CaCCs) and increased intracellular calcium concentrations ($[Ca^{2+}]_i$) in primary cultured human conjunctival cells. DA-6034 also increased $[Ca^{2+}]_i$ in mouse salivary gland cells and human corneal epithelial cells. $[Ca^{2+}]_i$ increase of DA-6034 was dependent on the $Ca^{2+}$ entry from extracellular and $Ca^{2+}$ release from internal $Ca^{2+}$ stores. Interestingly, these effects of DA-6034 were related to ryanodine receptors (RyRs) but not phospholipase C/inositol 1,4,5-triphosphate ($IP_3$) pathway and lysosomal $Ca^{2+}$ stores. These results suggest that DA-6034 induces $Ca^{2+}$ signaling via extracellular $Ca^{2+}$ entry and RyRs-sensitive $Ca^{2+}$ release from internal $Ca^{2+}$ stores in epithelial cells.

• 생명과학회지
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• 제32권9호
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• pp.712-720
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• 2022

비록 PM_2.5 노출과 다양한 안구 표면 질환과 관련성이 많은 선행 연구에서 알려졌지만, PM_2.5 가 각막에 미치는 세포 독성에 대한 연구는 거의 수행되지 않았다. 본 연구의 목적은 PM에 의한 각막 상피세포의 유해성을 평가하기 위한 in vitro 모델로서 쥐의 각막유래 상피세포(primary rat corneal epithelial cells, RCE cells)의 효능을 조사하는 것이다. 이를 위하여 쥐의 눈에서 분리한 1차 배양 세포가 각막 상피세포임을 pan-cytokeratin 염색을 통하여 확인하였으며, PM_2.처리에 의한 각막 상피세포의 형태학적 변화를 동반한 생존율의 억제는 세포사멸 유도와 관련이 있었다. 또한 PM_2.가 처리된 각막 상피세포에서는 ROS의 생성이 증가되었으며, 이는 미토콘드리아 기능 장애와 연관성이 있었다. 이와 함께 PM_2.는 각막 상피세포에서 NO, TNF-α, IL-1β 및 IL-6를 포함한 염증 매개인자 및 사이토카인의 생성을 증가시켰다. 아울러 heatmap 분석을 통해 BLNK, IL-1RA, Itga2b, ABCb1a 및 Ptgs2가 미세먼지 유도 안구 질환의 임상 치료를 위한 잠재적인 표적 유전자로서 제시하였다. 결론적으로 본 연구의 결과는 1차 쥐의 각막 상피세포가 PM_2.에 의한 각막 상피세포 병리기전 연구에 유용한 모델일 수 있으며, 산화적 및 염증성 반응이 PM_2.유발 안구 표면 장애 유도에 핵심적인 역할을 함을 알 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2295-2299
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• 2013

Background: To explore the role of caveolin-1(CAV-1) gene silencing on MAPK activation in lipopolysaccharide (LPS)-challenged human mammary epithelial cells. Methods: We established a MCF-10ACE of CAV-1 gene silencing from human mammary epithelial cell line MCF-10A by RNAi technology. DNA Microarray were used to detect the expression of inflammation-associated genes in MCF10ACE. Western blotting was used to examine the activation of MAPK in lipopolysaccharide(LPS)-challenged MCF-10A and MCF-10ACE. Moreover, immunofluorescence and Western bloting were performed to detect the co-localization of CAV-1 and toll-like receptor 4 (TLR4) in human mammary epithelial cells. Results: MCF-10ACE exhibited significant increases in inflammation-associated gene expression, especially IL-6 (~7-fold) and IL6R (~17-fold). In addition, LPS-induced p38 MAPK and JNK MAPK activation was significantly increased in MCF-10ACE. Furthermore, CAV-1 co-localized with TLR4 and appeared a negative correlation trend. Conclusion: CAV-1 gene silencing promotes MAPK activation via TLR4 signaling in human mammary epithelial cells response to LPS.

• BMB Reports
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• 제51권9호
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• pp.456-461
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• 2018

Chemoresistance is a major barrier to successful cisplatin-based chemotherapy for epithelial ovarian cancer (EOC), and emerging evidences suggest that microRNAs (miRNAs) are involved in the resistance. In this study, it was indicated that miR-363 downregulation was significantly correlated with EOC carcinogenesis and cisplatin resistance. Moreover, miR-363 overexpression could resensitise cisplatin-resistant EOC cells to cisplatin treatment both in vitro and in vivo. In addition, data revealed that EMT inducer Snail was significantly upregulated in cisplatin-resistant EOC cell lines and EOC patients and was a functional target of miR-363 in EOC cells. Furthermore, snail overexpression could significantly attenuate miR-363-suppressed cisplatin resistance of EOC cells, suggesting that miR-363-regulated cisplatin resistance is mediated by snail-induced EMT in EOC cells. Taken together, findings suggest that miR-363 may be a biomarker for predicting responsiveness to cisplatin-based chemotherapy and a potential therapeutic target in EOC.

• Toxicological Research
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• 제26권4호
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• pp.245-252
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• 2010

Epithelial-mesenchymal transition (EMT) is a complex process in which epithelial cells acquire the characteristics of invasive mesenchymal cells. EMT has been implicated in cancer progression and metastasis as well as the formation of many tissues and organs during development. Epithelial cells undergoing EMT lose cell-cell adhesion structures and polarity, and rearrange their cytoskeletons. Several oncogenic pathways such as transforming growth factor (TGF)-$\beta$, Wnt, and Notch signaling pathways, have been shown to induce EMT. These pathways have activated transcription factors including Snail, Slug, and the ZEB family which work as transcriptional repressors of E-cadherin, thereby making epithelial cells motile and resistant to apoptosis. Mounting evidence shows that EMT is associated with cell invasion and tumor progression. In this review, we summarize the characteristic features of EMT, pathways leading to EMT, and the role of EMT in cell invasion. Three topics are addressed in this review: (1) Definition of EMT, (2) Signaling pathways leading to EMT, (3) Role of EMT in cell invasion. Understanding the role of EMT in cell invasion will provide valuable information for establishing strategies to develop anti-metastatic therapeutics which modulate malignant cellular processes mediated by EMT.

• Journal of Microbiology and Biotechnology
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• 제25권4호
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• pp.479-491
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• 2015

Lactobacillus species have been shown to enhance intestinal epithelial barrier function, modulate host immune responses, and suppress the growth of pathogenic bacteria, yeasts, molds, and viruses. Thus, lactobacilli have been used as probiotics for treating various diseases, including intestinal disorders, and as biological preservatives in the food and agricultural industries. However, the molecular mechanisms used by lactobacilli to suppress pathogenic bacterial infections have been poorly characterized. We previously isolated Lactobacillus plantarum JSA22 from buckwheat sokseongjang, a traditional Korean fermented soybean food, which possessed high enzymatic, fibrinolytic, and broad-spectrum antimicrobial activity against foodborne pathogens. In this study, we investigated the effects of L. plantarum JSA22 on the growth of S. Typhimurium and S. Typhimurium-induced cytotoxicity by stimulating the host immune response in intestinal epithelial cells. The results showed that coincubation of S. Typhimurium and L. plantarum JSA22 with intestinal epithelial cells suppressed S. Typhimurium infection, S. Typhimurium-induced NF-κB activation, and IL-8 production, and lowered the phosphorylation of both Akt and p38. These data indicated that L. plantarum JSA22 has probiotic properties, and can inhibit S. Typhimurium infection of intestinal epithelial cells. Our findings can be used to develop therapeutic and prophylactic agents against pathogenic bacteria.

• Journal of Microbiology and Biotechnology
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• 제33권10호
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• pp.1309-1316
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• 2023

To exert their beneficial effects, it is essential for the commensal bacteria of probiotic supplements to be sufficiently protected as they pass through the low pH environment of the stomach, and effectively colonize the intestinal epithelium downstream. Here, we investigated the effect of a multilayer coating containing red ginseng dietary fiber, on the acid tolerance, and the adhesion and proliferation capacities of three Lactobacillus strains (Limosilactobacillus reuteri KGC1901, Lacticaseibacillus casei KGC1201, Limosilactobacillus fermentum KGC1601) isolated from Panax ginseng, using HT-29 cells, mucin-coated plates, and human pluripotent stem cell-derived intestinal epithelial cells as in vitro models of human gut physiology. We observed that the multilayer-coated strains displayed improved survival rates after passage through gastric juice, as well as high adhesion and proliferation capacities within the various gut epithelial systems tested, compared to their uncoated counterparts. Our findings demonstrated that the multilayer coat effectively protected commensal microbiota and led to improved adhesion and colonization of intestinal epithelial cells, and consequently to higher probiotic efficacy.

• Applied Microscopy
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• 제19권1호
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• pp.59-69
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• 1989

Ultrastructure of the secretory portion of the small ampullate gland in the orb web spider, Nephila clavata, has been investigated using the electron microscope. The secretory portion of this gland comprise two different regions which are a S-shaped storage sac and a long, convoluted tail. By the internal textures of the secretory granules, the sac is subdivided into two regions ; the proximal region near the tail and the distal region near the duct. Commonly single layered connectives cover the basal portion of the sac epithelium, and apical portion of the epithelial cells is occupied by the thick cuticles. Within the epithelial cells of both the proximal and distal region, several types of the secretory granules surrounded by a limiting membrane and had characteristic crystalloid are scattered throughout the cytoplasm. The granular size and its electron densities are not coincide with each other according to the maturation level of the granules. The wall of the tail is composed of single layer of columnar epithelial cells, and their nuclei are found at the basal portion of the cells. Dissimilar to the epithelial cells of the sac, apical cuticles are not found at this portion. In the cytoplasm of these cells, numerous secretory granules, synthesized from the rough endoplasmic reticula commonly and had fine fibrous materials, are found. At the cell surface bordering the lumen, microvilli are seen, arid along the cellular boundaries specialized septate junctions and desmosomes appeared.

• 한국가축번식학회지
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• 제19권2호
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• pp.135-140
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• 1995

The study was conducted to investigate on the survival rate of bisected porcine embryos co-cultured in 10% FCS(v/v)＋TCM-199 media containing hormones, oviductal epithelial cells and cumulus cells 0 to 72 hrs after bisection. In vitro survival rate was defined as development rate on in vitro culture or FDA-test. The results are summarized as follows ; 1. The survival rate of bisected porcine embryos cultrued in 10% FCS＋TCM-199 media contaning PMSG, hCG, PMSG＋hCG, hCG＋$\beta$-estradiol 0 to 20 hrs and 20 to 40 hrs were 37.6% and 37.5%, 28.6% and 28.6%, 35.7% and 28.8%, 30.8% and 23.1%, 38.5% and 30.7%, respectively. The survival rate of bisected embryos co-cultured in TCM-199 media containing hormones, oviductal epithelial cells and cumulus cells was significantly higher than that of non co-culture. 2. The survival rate of bisected porcine embryos co-cultured 10% FCS＋TCM-199 media containing oviductal epithelial cells 4 to 5 hrs and 20 to 24 hrs were 42.9% and 38.5%, respectively. 3. The survival rate of bisected porcine embryos co-cultured in 10% FCS＋TCM-199 media containing cumulus cells 4 to 5 hrs and 20 to 24 hrs were 40.0% and 35.7%, respectively.

• 한국환경과학회지
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• 제28권2호
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• pp.249-257
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• 2019

Ulmus davidiana Nakai (UDN) has been traditionally used as a herbal medicine to treat inflammatory diseases in Korea. In the present study, we investigated the anti-ecotoxic potential of a 116 kDa glycoprotein isolated from UDN (UDN glycoprotein) in human intestinal epithelial INT-407 cells. We demonstrated that UDN glycoprotein ($20{\mu}g/mL$) could inhibit the production of lactate dehydrogenase (LDH) induced by toluene, an ecotoxic substance. Additionally, we found that the toluene-induced intestinal cytotoxicity was mediated by the phosphorylation of p38 Mitogen-Activated Protein Kinase (MAPK) via the production of intracellular Reactive Oxygen Species (ROS). The UDN glycoprotein significantly decreased the levels of ROS production and p38 MAPK activation in toluene-stimulated INT-407 cells. Moreover, the UDN glycoprotein inhibits the phosphorylation of nuclear factor-kappa B ($NF-{\kappa}B$), which is responsible for the production of LDH, in toluene-stimulated INT-407 cells. Collectively, our data indicate that UDN glycoprotein is a natural antioxidant and a modulator of ecotoxicity signaling pathways in human intestinal epithelial cells.