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Jeong MJ, Lee KE, Chae YK, Nam OH, Lee HS, Choi SC. Correlations between skeletal maturity and dental calcification stages in Korean children. Eur J Paediatr Dent 2022; 23:101-105. [PMID: 35722843 DOI: 10.23804/ejpd.2022.23.02.03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
AIM To evaluate the relationship between dental calcification and skeletal maturity and to identify the tooth with the highest correlation with skeletal maturity index in Korean children. MATERIALS For 447 children (205 boys and 242 girls) aged between 5 and 13 years, hand-wrist and lateral cephalometric radiographs were taken to assess skeletal maturity by Fishman's skeletal maturity indicators (SMI) and Baccetti's cervical vertebrae maturation (CVM) stages. Dental panoramic radiographs were taken to assess dental maturity of the permanent mandibular canine, first and second premolar, and second molar using the method devised by Dermirjian. CONCLUSION Dental calcification stages determined by panoramic radiographs can be clinically used as useful indices to predict skeletal maturity in Korean children.
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Affiliation(s)
- M J Jeong
- Department of Pediatric Dentistry, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - K E Lee
- Department of Pediatric Dentistry, Kyung Hee University Dental Hospital, Seoul, Republic of Korea
| | - Y K Chae
- Department of Pediatric Dentistry, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - O H Nam
- Department of Pediatric Dentistry, Kyung Hee University Dental Hospital, Seoul, Republic of Korea
| | - H S Lee
- Department of Pediatric Dentistry, Kyung Hee University Dental Hospital, Seoul, Republic of Korea
| | - S C Choi
- Department of Pediatric Dentistry, Kyung Hee University Dental Hospital, Seoul, Republic of Korea
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Jeong MJ, Lim DS, Kim SO, Park C, Choi YH, Jeong SJ. Effect of rosmarinic acid on differentiation and mineralization of MC3T3-E1 osteoblastic cells on titanium surface. Anim Cells Syst (Seoul) 2021; 25:46-55. [PMID: 33717416 PMCID: PMC7935130 DOI: 10.1080/19768354.2021.1886987] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Titanium (Ti) is a widely used biomaterial for dental implants because of its outstanding biocompatibility for hard tissues. Osseointegration, the interaction between implanted biomaterials and living cells in bone, is essential for successful implantation. Rosmarinic acid (RA) is a plant-derived phytochemical with low toxicity and side effects and has various effects that can be applied as a therapeutic substance. The MC3T3-E1 osteoblastic cells on the Ti surface in medium with or without 14 μg/ml RA were used to test RA effects on osteoblast differentiation, cell viability and mineralization during differentiation. RA treatment increased osteoblast differentiation, cell viability and mineralization in MC3T3-E1 osteoblastic cells on Ti surface during differentiation, upregulating Runx-2 and OPG, but downregulating RANKL. This study suggest that RA should be applied as an effective functional and therapeutic substance to enhance osseointegration of osteoblast cells by increasing differentiation, mineralization, and bone formation through the RANKL/RANK/OPG pathway during the differentiation in MC3T3-E1 osteoblastic cells on the Ti surface.
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Affiliation(s)
- Moon-Jin Jeong
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju, Korea
| | - Do-Seon Lim
- Department of Dental Hygiene, Graduate School of Public Health Science, Eulji University, Seongnam, Korea
| | - Sung Ok Kim
- Department of Food Science and Biotechnology, College of Engineering, Kyungsung University, Busan, Korea
| | - Cheol Park
- College of Liberal Studies, Division of Basic Sciences, Dong-eui University, Busan, Korea
| | - Yung Hyun Choi
- Department of Biochemistry, College of Korean Medicine, Dong-eui University, Busan, Korea
| | - Soon-Jeong Jeong
- Department of Dental Hygiene, College of Health Science, Youngsan University, Yangsan, Korea.,Institute of Basic Science for Well-Aging, Youngsan University, Yangsan, Korea
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Jeong MJ, Kil KS, Lee MH, Lee SY, Lee HJ, Lim DS, Jeong SJ. Inflammatory Effect of Light-Emitting Diodes Curing Light Irradiation on Raw264.7 Macrophage. ACTA ACUST UNITED AC 2019. [DOI: 10.17135/jdhs.2019.19.2.133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Moon-Jin Jeong
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 61452, Korea
| | - Ki-Sung Kil
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 61452, Korea
| | - Myoung-Hwa Lee
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 61452, Korea
| | - Seung-Yeon Lee
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 61452, Korea
| | - Hye-Jin Lee
- Department of Dental Hygiene, Dong-Pusan College, Busan 48000, Korea
| | - Do-Seon Lim
- Department of Dental Hygiene, Graduate School of Public Health Science, Eulji University, Seongnam 13135, Korea
| | - Soon-Jeong Jeong
- Department of Dental Hygiene, College of Health Science, Youngsan University, Yangsan 50510, Korea
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Choi BD, Lim HJ, Lee SY, Lee MH, Kil KS, Lim DS, Jeong SJ, Jeong MJ. Thymosin β4 is associated with bone sialoprotein expression via ERK and Smad3 signaling pathways in MDPC-23 odontoblastic cells. Int J Mol Med 2018; 42:2881-2890. [PMID: 30226623 DOI: 10.3892/ijmm.2018.3865] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 08/27/2018] [Indexed: 11/05/2022] Open
Abstract
Thymosin β4 (Tβ4) regulates the expression of molecules associated with dentinogenesis, including bone sialoprotein (BSP). BSP regulates the initiation of mineralization and the direction of dentin growth. However, the association between Tβ4 signaling and BSP expression in odontoblasts remains unclear. Therefore, the aim of the present study was to investigate Tβ4 mRNA expression in odontoblasts during dentinogenesis and the association between the Tβ4 signaling pathway and BSP expression in MDPC‑23 odontoblastic cells. Expression and localization of Tβ4 mRNA was determined by in situ hybridization during mouse tooth development. The effect of Tβ4 signaling on BSP expression was investigated by reverse transcription polymerase chain reaction, western blot analysis, immunofluorescence and a luciferase reporter assay in the presence or absence of specific inhibitors of mitogen activated protein kinase kinase (PD98059) and mothers against decapentaplegic homolog 3 (Smad3; SIS3) in MDPC‑23 cells. The expression of Tβ4 mRNA in the odontoblast layer was highest at postnatal day 5, known as the advanced bell stage, when odontoblasts actively secrete dentin matrix proteins. Tβ4 increased BSP mRNA and protein levels in MDPC‑23 cells, but this was inhibited by PD98059 or SIS3 treatment. Tβ4 increased levels of phosphorylated (p) extracellular signal‑regulated kinase (ERK)1/2, pSmad3, pβ‑catenin, and runt‑related transcription factor 2 (Runx2) protein, but these effects were inhibited by PD98059 or SIS3. Tβ4 induced the nuclear translocation of Runx2 and pSmad3, while nuclear translocation of β‑catenin was decreased. Tβ4 significantly increased BSP promoter activity, which was decreased by PD98059 or SIS3 treatment. Tβ4 induced BSP expression in MDPC‑23 cells via ERK and Smad3 signaling pathways, suggesting its role as a signaling molecule in odontoblasts for regulating BSP secretion during dentinogenesis.
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Affiliation(s)
- Baik-Dong Choi
- Department of Oral Histology and Developmental Biology, College of Dentistry, Chosun University, Gwangju 61452, Republic of Korea
| | - Hee-Jung Lim
- Department of Dental Hygiene, College of Health Science, Eulji University, Seongnam, Gyeonggi‑do 13135, Republic of Korea
| | - Seung-Yeon Lee
- Department of Oral Histology and Developmental Biology, College of Dentistry, Chosun University, Gwangju 61452, Republic of Korea
| | - Myoung-Hwa Lee
- Department of Oral Histology and Developmental Biology, College of Dentistry, Chosun University, Gwangju 61452, Republic of Korea
| | - Ki-Sung Kil
- Department of Oral Histology and Developmental Biology, College of Dentistry, Chosun University, Gwangju 61452, Republic of Korea
| | - Do-Seon Lim
- Department of Dental Hygiene, College of Health Science, Eulji University, Seongnam, Gyeonggi‑do 13135, Republic of Korea
| | - Soon-Jeong Jeong
- Department of Dental Hygiene, College of Health Science, Youngsan University, Yangsan, Gyeongsangnam‑do 50510, Republic of Korea
| | - Moon-Jin Jeong
- Department of Oral Histology and Developmental Biology, College of Dentistry, Chosun University, Gwangju 61452, Republic of Korea
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Choi BD, Lim DS, Lee SY, Nho TH, Jeong SJ, Ko YM, Gang SN, Kim YJ, Piao XH, Jeong MJ. Thymosin β4 Reduces H₂O₂ Induced Oxidative Stress in MC3T3-E1 Cells on Titanium Surface. J Nanosci Nanotechnol 2018; 18:893-897. [PMID: 29448512 DOI: 10.1166/jnn.2018.14865] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Thymosin β4 (Tβ4) is known to inhibit an inflammatory response and to increase the survival of osteoblasts on titanium (Ti) surfaces. Ti is the most widely used graft material in dentistry; however, an inflammatory response induced following implant placement results in the generation of reactive oxygen species (ROS). The oxidative stress from the production of ROS such as nitric oxide (NO) and hydrogen peroxide (H2O2) can damage surrounding cells, resulting in implant failure by decreasing cell viability. Thus, the aim of this study was to determine the biological effects of Tβ4 on the oxidative stress induced to MC3T3-E1 preosteoblasts on the Ti surface. Based on an MTT assay and bromodeoxyuridine immunofluorescence staining, Tβ4 was found to increase the proliferation of the H2O2-exposed MC3T3-E1 cells on Ti discs. Reverse transcription-polymerase chain reaction and western blot analyses showed that Tβ4 decreased the mRNA and protein expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in H2O2-exposed MC3T3-E1 cells on the Ti discs. Tβ4 inhibited the synthesis of intracellular ROS and the secretion of NO and prostaglandin E2 (PGE2) from H2O2-exposed MC3T3-E1 cells on the Ti discs. In conclusion, Tβ4 inhibits H2O2-induced iNOS and COX-2 expression with a decrease in ROS, NO, and PGE2 synthesis, which leads to improved cell survival with low cytotoxicity under an oxidative stress condition in MC3T3-E1 cells on the Ti surface. This suggests that Tβ4 may be a crucial molecule to reduce oxidative stress-induced cell damage or hypoxia, leading to promoted osseointegration on the Ti surface during implant placement.
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Affiliation(s)
- Baik-Dong Choi
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju, 61452, Korea
| | - Do-Seon Lim
- Department of Dental Hygiene, College of Health Science, Eulji University, Seongnam, 13135, Korea
| | - Seung-Yeon Lee
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju, 61452, Korea
| | - Tae-Hee Nho
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju, 61452, Korea
| | - Soon-Jeong Jeong
- Department of Dental Hygiene, College of Health Science, Youngsan University, Yangsan, 50510, Korea
| | - Yeong-Mu Ko
- Department of Dental Material, School of Dentistry, Chosun University, Gwangju, 61452, Korea
| | - Sung-Nam Gang
- Department of Orthodontics, School of Dentistry, Chosun University, Gwangju, 61452, Korea
| | - Young-Joon Kim
- Department of Periodontology, School of Dentistry, Chonnam National University, Gwangju, 61186, Korea
| | - Xing-Hui Piao
- Department of Stomatology, Affiliated Hospital of Yanbian University, Yanji, 133000, China
| | - Moon-Jin Jeong
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju, 61452, Korea
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Affiliation(s)
- Moon-Jin Jeong
- Department of Oral Histology and Biology, School of Dentistry, Chosun University, Gwangju 61452, Korea
| | - Hye-Sun Shin
- Department of Dental Hygiene, College of Health Science, Eulji University, Seongnam 13135, Korea
| | - Soon-Jeong Jeong
- Department of Dental Hygiene, College of Health Science, Youngsan University, Yangsan 50510, Korea
| | - Do-Seon Lim
- Department of Dental Hygiene, College of Health Science, Eulji University, Seongnam 13135, Korea
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Lee MH, Cha HJ, Choi EO, Han MH, Kim SO, Kim GY, Hong SH, Park C, Moon SK, Jeong SJ, Jeong MJ, Kim WJ, Choi YH. Antioxidant and cytoprotective effects of morin against hydrogen peroxide-induced oxidative stress are associated with the induction of Nrf-2-mediated HO-1 expression in V79-4 Chinese hamster lung fibroblasts. Int J Mol Med 2017; 39:672-680. [DOI: 10.3892/ijmm.2017.2871] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 01/16/2017] [Indexed: 11/05/2022] Open
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Lee SY, Nho TH, Choi BD, Jeong SJ, Lim DS, Jeong MJ. Secretory leukocyte protease inhibitor reduces inflammation and alveolar bone resorption in LPS-induced periodontitis in rats and in MC3T3-E1 preosteoblasts. Anim Cells Syst (Seoul) 2016. [DOI: 10.1080/19768354.2016.1250817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Lee TK, Park C, Jeong SJ, Jeong MJ, Kim GY, Kim WJ, Choi YH. Sanguinarine Induces Apoptosis of Human Oral Squamous Cell Carcinoma KB Cells via Inactivation of the PI3K/Akt Signaling Pathway. Drug Dev Res 2016; 77:227-40. [PMID: 27363951 DOI: 10.1002/ddr.21315] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 05/25/2016] [Indexed: 01/16/2023]
Abstract
Preclinical Research Sanguinarine, an alkaloid isolated from the root of Sanguinaria canadensis and other plants of the Papaveraceae family, selectively induces apoptotic cell death in a variety of human cancer cells, but its mechanism of action requires further elaboration. The present study investigated the pro-apoptotic effects of sanguinarine in human oral squamous cell carcinoma KB cells. Sanguinarine treatment increased DR5/TRAILR2 (death receptor 5/TRAIL receptor 2) expression and enhanced the activation of caspase-8 and cleavage of its substrate, Bid. Sanguinarine also induced the mitochondrial translocation of pro-apoptotic Bax, mitochondrial dysfunction, cytochrome c release to the cytosol, and activation of caspase-9 and -3. However, a pan-caspase inhibitor, z-VAD-fmk, reversed the growth inhibition and apoptosis induced by sanguinarine. Sanguinarine also suppressed the phosphorylation of phosphoinositide 3-kinase (PI3K) and Akt in KB cells, while co-treatment of cells with sanguinarine and a PI3K inhibitor revealed synergistic apoptotic effects. However, pharmacological inhibition of AMP-activated protein kinase and mitogen-activated protein kinases did not reduce or enhance sanguinarine-induced growth inhibition and apoptosis. Collectively, these findings indicate that the pro-apoptotic effects of sanguinarine in KB cells may be regulated by a caspase-dependent cascade via activation of both intrinsic and extrinsic signaling pathways and inactivation of PI3K/Akt signaling. Drug Dev Res 77 : 227-240, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Tae Kyung Lee
- Department of Biology, New York University, New York, NY, 10012, USA
| | - Cheol Park
- Department of Molecular Biology, College of Natural Sciences and Human Ecology, Dongeui University, Busan, 614-714, South Korea
| | - Soon-Jeong Jeong
- Department of Dental Hygiene, College of Health Sciences, Youngsan University, Yangsan, 626-790, South Korea
| | - Moon-Jin Jeong
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju, 501-759, South Korea
| | - Gi-Young Kim
- Laboratory of Immunobiology, Department of Marine Life Sciences, Jeju National University, Jeju, 690-756, South Korea
| | - Wun-Jae Kim
- Department of Urology, Chungbuk National University, College of Medicine and Institute for Tumor Research, Cheongju, 28644, South Korea
| | - Yung Hyun Choi
- Anti-Aging Research Center, Dongeui University, Busan, 614-714, South Korea.,Department of Biochemistry, Dongeui University College of Korean Medicine, Busan, 614-714, South Korea
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Choi BD, Lee SY, Jeong SJ, Lim DS, Cha HJ, Chung WG, Jeong MJ. Secretory leukocyte protease inhibitor promotes differentiation and mineralization of MC3T3-E1 preosteoblasts on a titanium surface. Mol Med Rep 2016; 14:1241-6. [PMID: 27279420 DOI: 10.3892/mmr.2016.5381] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 03/08/2016] [Indexed: 11/06/2022] Open
Abstract
Mineralized bone matrix constituted with collagenous and non-collagenous proteins was synthesized by osteoblasts differentiated from mesenchymal stem cells. Secretory leukocyte protease inhibitor (SLPI), a serine protease inhibitor, promotes cell migration and proliferation, and suppresses the inflammatory response. Recent studies reported that SLPI regulates the formation of dentin and mineralization by odontoblasts and increases the adhesion and viability of preosteoblasts on a titanium (Ti) surface. Ti and its alloys are widely used implant materials in artificial joints and dental implants owing to their biocompatibility with bone. Therefore, this study aimed to examine whether SLPI can be an effective molecule in promoting differentiation and mineralization of osteoblasts on a Ti surface. In order to investigate the effects of SLPI on osteoblasts, an MTT assay, PCR, western blotting and Alizarin Red S staining were performed. The results demonstrated that SLPI increased the viability of osteoblasts during differentiation on Ti discs compared with that of the control. The expression levels of SLPI mRNA and protein were higher than that of the control after treatment of osteoblasts with SLPI on Ti discs during differentiation. SLPI increased the formation of mineralized nodules and mRNA expression of alkaline phosphatase, dentin sialophosphoprotein, dentin matrix protein 1, bone sialoprotein, and collagen I in osteoblasts on Ti discs compared with that of the control. In conclusion, SLPI increases the viability and promotes the differentiation and mineralization of osteoblasts on Ti surfaces, suggesting that SLPI is an effective molecule for achieving successful osseointegration between osteoblasts and a Ti surface.
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Affiliation(s)
- Baik-Dong Choi
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 501‑759, Republic of Korea
| | - Seung-Yeon Lee
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 501‑759, Republic of Korea
| | - Soon-Jeong Jeong
- Department of Dental Hygiene, Youngsan University, Yangsan, Gyeongsangnam‑do 626‑790, Republic of Korea
| | - Do-Seon Lim
- Department of Dental Hygiene, Eulji University, Seongnam, Gyeonggi 461‑713, Republic of Korea
| | - Hee-Jae Cha
- Department of Parasitology and Genetics, College of Medicine, Kosin University, Busan 602‑072, Republic of Korea
| | - Won-Gyun Chung
- Department of Dental Hygiene, Wonju College of Medicine, Yonsei University, Wonju, Gangwon 220‑701, Republic of Korea
| | - Moon-Jin Jeong
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 501‑759, Republic of Korea
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Jeong SJ, Jeong MJ. Effect of Thymosin beta4 on the Differentiation and Mineralization of MC3T3-E1 Cell on a Titanium Surface. J Nanosci Nanotechnol 2016; 16:1979-1983. [PMID: 27433712 DOI: 10.1166/jnn.2016.11928] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Osteoblasts are responsible for the synthesis of bone matrix through the secretion of collagenous and non-collagenous proteins with mineralization. Thymosin beta4 (Tbeta4) is an actin-sequestering peptide that is involved in the regulation of cell proliferation, differentiation and motility. A recent study reported that the inhibition of Tbeta4 mRNA synthesis strongly decreases the level of gene expression of bone sialoprotein (BSP), dentin sialophosphoprotein (DSPP), osteocalcin (OCN), osteonectin (ON) and collagen type I (Col I) with mineralization during differentiation in odontoblasts. Titanium (Ti) is used commonly as an implant material for dental implants, which have strong mechanical potential and good biocompatibility with bone. This study examined whether Tbeta4 can be a potential molecule for promoting the differentiation and mineralization of MC3T3-E1 cells on a Ti surface. Tbeta4 increased the viability of MC3T3-E1 cells during differentiation on Ti discs compared to that of the control. The expression of Tbeta4 mRNA and protein in the Tbeta4-treated MC3T3-E1 cells was higher than the control during differentiation on the Ti discs. In addition, Tbeta4 increased the formation of mineralization nodules and the mRNA expression of alkaline phosphatase (ALP), DSPP, dentin matrix protein1 (DMP1), BSP and Col I compared to that of the control in MC3T3-E1 cells during differentiation on Ti discs. From the results, Tbeta4 increased the viability and promoted the differentiation and mineralization of MC3T3-E1 cells on Ti discs. This highlights the potential use of Tbeta4 for increasing osseointegration through osteoblast differentiation and mineralization on Ti discs.
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Jeong SJ, Choi BD, Lee HY, Hwang YH, Kim BH, Cho YI, Yun JJ, Lee BH, Jeong MJ. 660 nm Red LED Induces Secretory Leukocyte Protease Inhibitor (SLPI) in Lipopolysaccharide-Stimulated RAW264.7 Cell. J Nanosci Nanotechnol 2015; 15:5610-5616. [PMID: 26369126 DOI: 10.1166/jnn.2015.10465] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
SLPI acts as a modulator of the innate immune responses of macrophages, neutrophils and odontoblasts, and LPS-inducible anti-inflammatory cytokine to suppress the production of pro-inflammatory products by macrophages. Many studies have revealed the effects of light emitting diodes (LEDs) on the tissue repair and inflammatory responses. Although the anti-inflammatory mechanisms of irradiation with LEDs in gingival fibroblasts are known, the effects of 660 nm red LEDs on the inflammation remain unclear. Moreover, there is no report regarding the molecular mechanism for the relationship between SLPI and biological effects of LEDs. The effects of 660 nm red LEDs on inflammation with SLPI were investigated by examining the effects of 660 nm LED on the SLPI expression of RAW264.7 cells after LPS stimulation. This paper reports that the 660 nm red LED induced SLPI expression or reduced the LPS response, and inhibited NF-κB activation directly, leading to the suppression of pro-inflammatory cytokines, such as TNF-α and IL-1β, suggesting that it might be a useful wavelength LED for inflammation therapy.
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Choi BD, Jeong SJ, Lee HY, Lim DS, Lee BH, Bae CS, Jeong MJ. The Effect of Thymosin β4 for Osteoblast Adhesion on Titanium Surface. J Nanosci Nanotechnol 2015; 15:5663-5667. [PMID: 26369135 DOI: 10.1166/jnn.2015.10464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Titanium (Ti) is the most widely used implant material in dentistry and orthopedics but the release of metal ions from Ti implants results in increased bone resorption by enhancing the production of inflammatory cytokines from the macrophages and facilitating osteoclast differentiation. Thymosin β4 (Tβ4) has several biological activities, such as promoting wound healing, angiogenesis, cell proliferation and migration in mammalian cells. This study examined the role of Tβ4 in osteoblasts via focal adhesions (FAs) and ERK1/2 signaling related to cell adhesion and proliferation for cell survival on the Ti surface. As a result, cell adhesion and proliferation increased in the Tβ4 treated cells (Tβ4/MC3T3-E1) but was significantly lower in the Tβ4 knock-down cells by Tβ4-siRNA (si-Tβ4/MC3T3-E1) than that of the untreated cells. The levels of FAK phosphorylation, paxillin expression, and paxillin localization were higher in the Tβ4/IMC3T3-E1 cells than that of the untreated cells but lower in the si-Tβ4/MC3T3-E1 cells. In addition, the levels of cell proliferation, Grb2 and Ras protein expression and phosphorylation of ERK1/2 were higher in the Tβ4/MC3T3-E1 cells than in the untreated cells but lower in the si-Tβ4/IMC3T3-E1 cells. These results suggest that Tβ4 might be a good nanomolecule that promotes osteoblast survival by facilitating adhesion and proliferation on the Ti surface.
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Jeong JO, Wang G, Jeong SJ, Choi BD, Lee HY, Jeong MJ. Function of Secretory Leukocyte Protease Inhibitor (SLPI) in Odontoblast During Mouse Tooth Development. J Nanosci Nanotechnol 2015; 15:120-124. [PMID: 26328314 DOI: 10.1166/jnn.2015.8384] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Secretory leuckocyte protease inhibitor (SLPI) is thought as a regulating protein on the synthesis and degradation of matrix proteins. But there was no report of expression and function of SLPI on the tooth development, especially on the odontoblasts. As observed by in-situ hybridization and immunohistochemical analysis, SLPI was expressed in odontoblasts and predentin on post-natal day 4 (PN4). On PN10, SLPI was observed under the dentin and apical region including odontoblasts processes. Further, on PN15, expression of SLPI was the same pattern compared to PN10. SLPI was expressed under layer of the odontoblasts and in odontoblasts on PN20. Matrix metalloproteinase-2 (MMP-2) and -9 levels in SLPI/MDPC-23 cells were higher than that of the MDPC-23 cells. The gene expression of SLPI, bone sialoprotein (BSP), osteocalcin (OCN), osteonectin (ON), and collagen type I (Col I) was higher in SLPI/MDPC-23 than that of MDPC-23 cells and the expression of dentin sialophosphoprotein (DSPP) was lower in SLPI/MDPC-23. Taken together, our results suggest that SLPI may be a MMP-2 and -9 regulating molecule in odontoblasts during dentin matrix formation and acts as a signaling molecule for dentin matrix related proteins during odontoblasts differentiation and mineralization.
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Jeong SJ, Wang G, Choi BD, Hwang YH, Kim BH, Ko YM, Jeong MJ. Secretory Leukocyte Protease Inhibitor (SLPI) Increases Focal Adhesion in MC3T3 Osteoblast on Titanium Surface. J Nanosci Nanotechnol 2015; 15:200-204. [PMID: 26328330 DOI: 10.1166/jnn.2015.8383] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An appropriate interaction between implanted materials and the surrounding tissue is essential for successful implantation. Titanium (Ti) and some of its alloys have been used in dentistry and orthopedics as a substitutive material for hard tissue, such as teeth or natural bone. Nevertheless, metal ions released from titanium and alloy implants have adverse biological effects on biological tissues or cells. Secretory leukocyte protease inhibitor (SLPI) promotes cell migration, proliferation and wound healing. FAK and ERK1/2 signaling regulate cell adhesion and proliferation for cell survival. This study evaluated the potential of SLPI as a molecule to increase the cell adhesion on the Ti surface. Compared with the untreated cells, SLPI increased the adhesion of MC3T3-E1 cells to Ti discs, formation of actin stress fibers, paxillin expression and the phosphorylation of FAK. Moreover, SLPI enhanced the level of Grb2 and Ras expression and ERK1/2 phosphorylation in the MC3T3-E1 cells on Ti discs. These results suggest that SLPI can increase the interaction between the implanted Ti material and surrounding bone in orthodontic and dental surgery, making an effective nanomolecule for successful implantation.
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Kim EM, Lee HY, Lee EH, Lee KM, Park M, Ji KY, Jang JH, Jeong YH, Lee KH, Yoon IJ, Kim SM, Jeong MJ, Kim KD, Kang HS. Formaldehyde exposure impairs the function and differentiation of NK cells. Toxicol Lett 2013; 223:154-61. [DOI: 10.1016/j.toxlet.2013.09.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 09/10/2013] [Accepted: 09/12/2013] [Indexed: 02/02/2023]
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Kim YS, Cho IH, Jeong MJ, Jeong SJ, Nah SY, Cho YS, Kim SH, Go A, Kim SE, Kang SS, Moon CJ, Kim JC, Kim SH, Bae CS. Therapeutic effect of total ginseng saponin on skin wound healing. J Ginseng Res 2013; 35:360-7. [PMID: 23717081 PMCID: PMC3659532 DOI: 10.5142/jgr.2011.35.3.360] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2011] [Revised: 06/21/2011] [Accepted: 06/21/2011] [Indexed: 11/30/2022] Open
Abstract
In this study, we investigated the effects of total ginseng saponin (TGS) on the cutaneous wound healing process using histological analysis. A total of 24 ICR mice, 5-weeks-old, were used for all in vivo experiments. Mice were divided into control and TGS-treated groups and four equidistant 1-cm full-thickness dorsal incisional wounds were created. The wounds were extracted at days 1, 3, 5, and 7 post-injury for histomorphometrical analysis including wound area and contracture measurements, keratinocyte migration rate, and calculation of infiltrating inflammatory cells. The results showed that the wound area was smaller and keratinocyte migration rate was higher in the TGS-treated group than that of the control group from days 3 to 7. Inflammatory cells in the TGS-treated group at days 1 and 3 were reduced compared to the control group. Wound contraction in the TGS-treated group was greater than in the control group on days 3 to 5, and collagen deposition in the TGS-treated group was higher than in the control group during wound healing. The results indicate a beneficial effect of TGS when used to treat skin wounds.
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Affiliation(s)
- Young Soo Kim
- Department of Veterinary Surgery, Chonnam National University College of Veterinary Medicine, Gwangju 500-757, Korea
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Hong DG, Park NY, Chong GO, Cho YL, Park IS, Jeong MJ, Park JY, Lee YS. The correlation between expression of synuclein-gamma, glucose transporter-1, and survival outcomes in endometrioid endometrial carcinoma. EUR J GYNAECOL ONCOL 2013; 34:128-131. [PMID: 23781582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PURPOSE To evaluate the correlation between immunohistochemical expression of synuclein-gamma, glucose transporter-1, and survival outcomes in endometrioid endometrial carcinoma. MATERIALS AND METHODS A tissue microarray was constructed using formalinfixed, paraffin-embedded tissue that included 23 early and 18 advanced cases. The intensity and area of the immunohistochemical reactions were evaluated using the semi-quantitative scoring system. RESULTS Synuclein-y expression was higher in the advanced stage, although it was not statistically significant (p = 0.51). Glucose transporter-1 was overexpressed in the advanced stage (p = 0.01). Synuclein-gamma (score = 0 vs > 0) and glucose transporter-1 (score < or = 7 vs > 7) did not show any differences in overall survival (p = 0.54, p = 0.48) and disease-free survival (p = 0.61, p = 0.14). CONCLUSION In this study the expression of synuclein-y and glucose transporter-1 were not considered to be a prognostic factor and were not related with survival outcomes in endometrioid endometrial carcinoma.
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Affiliation(s)
- D G Hong
- Gynecologic Cancer Center, Kyungpook National University Medical Center, Daegu, Republic of Korea
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19
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Choi BD, Yun SH, Jeong SJ, Wang G, Kim HJ, Lim DS, Jeong MJ. Expression of thymosin β4 in odontoblasts during mouse tooth development. Int J Mol Med 2012; 29:841-7. [PMID: 22344518 DOI: 10.3892/ijmm.2012.913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 01/16/2012] [Indexed: 11/06/2022] Open
Abstract
Thymosin β4 (Tβ4) is expressed in developing tissue, where it stimulates cell differentiation and migration. Further, Tβ4 is expressed during molar development in mice, but the expression and function of Tβ4 in odontoblasts during mammalian tooth development have not yet been reported. Therefore, this study examined the expression and function of Tβ4 in differentiating odontoblasts during tooth development. As observed by immunohistochemistry, Tβ4 was expressed in the oral epithelium and inside cells of the tooth bud on embryonic day 15 (E15). Further, on E17, Tβ4 was expressed strongly in the dental lamina and oral epithelium, but only expressed in part of the cells in the outer and inner dental epithelium. Tβ4 was strongly expressed in the entire cytoplasm of odontoblasts on postnatal day 1 (PN1) and expressed intensively in the apical area of odontoblasts on PN4. Further, expression of Tβ4 was increased gradually in odontoblasts from PN1 to PN21. In an odontoblast cell line, MDPC-23, expression of Tβ4 mRNA and protein was increased strongly on day 4 and gradually decreased from day 14. The gene expression of dentin sialophosphoprotein (DSPP), bone sialoprotein (BSP), osteocalcin (OCN), osteonectin (ON), and collagen type I, related with mineralization, was significantly decreased in si-Tβ4/MDPC-23 during differentiation compared to that in MDPC-23 cells. Taken together, our results suggest that Tβ4 may be involved in oral epithelial cell proliferation at the initial stage of tooth development and regulates the expression and secretion of proteins during odontoblast differentiation.
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Affiliation(s)
- Baik-Dong Choi
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 501-759, Republic of Korea
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Lim DS, Kim SR, Choi BD, Jeong SJ, Wang G, Kim HK, Kim BH, Goo JH, Jeong MJ. Dynamin II involves in cell migration and actin formation of NIH3T3 cells. J Nanosci Nanotechnol 2012; 12:690-695. [PMID: 22524041 DOI: 10.1166/jnn.2012.5377] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
It was previously reported that in Ras transformed NIH3T3 cells, dynamin II acts as an intermediate messenger in the Ras signal transduction pathway leading to membrane ruffling and cell migration. However, these results do not provide sufficient evidence of a relationship between dynamin II and the Ras signal transduction pathway leading to membrane ruffling and cell migration. The results showed that a dynamin II association with myosin II as a signaling molecule is involved in NIH3T3 cell migration through the Ras/PI3K signaling pathway, and is associated with the p85 subunit of PI3K. Confocal microscopy also revealed co-localization between dynamin II and paxillin after PDGF stimulation. In addition, immunofluorescence results showed that dynamin II was colocalized with the actin filament. After stimulating the NIH3T3 cells with PDGF and treating them with an actin inhibitor, such as Cytochalasin D, it was observed that dynamin II with the myosin II complex inhibited binding to the actin. Therefore, dynamin II is localized in focal adhesion when cell migration is triggered and binds to the actin filament component, suggesting that it is a good candidate nanomolecule to regulate the cell attachment and migration to the materials such as implants etc.
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Affiliation(s)
- Do-Seon Lim
- Department of Oral Histology & Developmental Biology, School of Dentistry, Chosun University, Gwangju 501-759, Korea
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Ashcroft GS, Jeong MJ, Ashworth JJ, Hardman M, Jin W, Moutsopoulos N, Wild T, McCartney-Francis N, Sim D, McGrady G, Song XY, Wahl SM. Tumor necrosis factor-alpha (TNF-α) is a therapeutic target for impaired cutaneous wound healing. Wound Repair Regen 2011; 20:38-49. [PMID: 22151742 DOI: 10.1111/j.1524-475x.2011.00748.x] [Citation(s) in RCA: 179] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 09/19/2011] [Indexed: 01/09/2023]
Abstract
Impaired wound healing states lead to substantial morbidity and cost with treatment resulting in an expenditure of billions of dollars per annum in the U.S. alone. Both chronic wounds and impaired acute wounds are characterized by excessive inflammation, enhanced proteolysis, and reduced matrix deposition. These confounding factors are exacerbated in the elderly, in part, as we report here, related to increased local and systemic tumor necrosis factor-alpha (TNF-α) levels. Moreover, we have used a secretory leukocyte protease inhibitor (SLPI) null mouse model of severely impaired wound healing and excessive inflammation, comparable to age-related delayed human healing, to demonstrate that topical application of anti-TNF-α neutralizing antibodies blunts leukocyte recruitment and NFκB activation, alters the balance between M1 and M2 macrophages, and accelerates wound healing. Following antagonism of TNF-α, matrix synthesis is enhanced, associated with suppression of both inflammatory parameters and NFκB binding activity. Our data suggest that inhibiting TNF-α is a critical event in reversing the severely impaired healing response associated with the absence of SLPI, and may be applicable to prophylaxis and/or treatment of impaired wound healing states in humans.
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Affiliation(s)
- Gillian S Ashcroft
- Oral Infection and Immunity Branch, National Institute of Dental & Craniofacial Research, National Institutes of Health, Bethesda, Maryland 20892, USA
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22
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Jeong SJ, Kim SS, Bae CS, Park JJ, Choi BD, Wang G, Jung MJ, Jang HS, Kim BO, Lim DS, Cho YS, Jeong MJ. Delayed healing and induction of secretory leukocyte protease inhibitor in polycystic ovary syndrome rat skin wounds. Int J Mol Med 2011; 29:185-94. [PMID: 22020578 DOI: 10.3892/ijmm.2011.816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 09/02/2011] [Indexed: 11/05/2022] Open
Abstract
Secretory leukocyte protease inhibitor (SLPI) and estrogen promote wound healing through a decrease in the excessive inflammatory response, accelerating re-epithelialization and increasing the amount of collagen deposition. The excessive administration of estradiol valerate (EV) using hormonal therapy decreases the concentration of estrogen abruptly and induces the polycystic ovary syndrome (PCOS). In this study, the PCOS rat skin wound area was wider than that of the normal groups and the rate of keratinocyte migration in PCOS was lower than the normal group. The numbers of inflammatory cells and macrophages recruited in the PCOS group were larger than that of the normal group. More collagen was deposited in the healing area of the normal group than in the PCOS group. The level of SLPI expression was higher in the PCOS group than the normal group after wounding, with the exception of the epithelium. On the other hand, mRNA and protein expression levels of transforming growth factor-β1 (TGF-β1) were lower in the PCOS group than in the normal group. Matrix metalloproteinase-2 (MMP-2) and MMP-9 levels in the PCOS group were significantly lower than that of the normal group. Therefore, increased SLPI in PCOS skin wounds may help prevent an excessive inflammatory response and aberrant collagen deposition but not are sufficient to accelerate PCOS skin wound healing, suggesting that SLPI may act as a local rather than a systemic modulating molecule in PCOS rat skin wounds.
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Affiliation(s)
- Soon-Jeong Jeong
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju 501-759, Republic of Korea
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Oh JH, Choi BD, Park JJ, Jeong SJ, Kim JS, Kim JD, Lim DS, Kim BH, Cho YI, Jeong MJ. Expression of dynamin II in odontoblast during mouse tooth development. J Nanosci Nanotechnol 2011; 11:7096-7099. [PMID: 22103132 DOI: 10.1166/jnn.2011.4854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Odontoblasts secrete a collagen-based matrix and release numerous membrane-bound matrix vesicles, which are involved in dentin formation during tooth development. Dynamin II is a GTPase protein that contributes a variety of vesicular budding events, such as endocytotic membrane fission, caveolae internalization and protein trafficking in the Golgi apparatus. However, the expression and function of dynamin II in odontoblasts has not been reported. Therefore, this study examined the expression and possible role of dynamin II in odontoblasts during tooth development and mineralization. The levels of mRNA and protein expression in MDPC23 cells were significantly high at the early stages of differentiation and then decreased gradually thereafter. Immunohistochemistry showed that dynamin II was not expressed near the region of the odontoblasts at embryonic day 17 (E17) and E21. However, dynamin II was expressed strongly in the odontoblast layer at postnatal day 1 (PN1) and decreased gradually at PN3 and PN5. In addition, at PN15 in the functional stage, the dynamin II protein was also expressed in the odontoblast process as well as adjacent to the nuclear region. In conclusion, dynamin II may be involved in the transport of vesicles containing collageneous and non-collageneous proteins for dentin formation in odontoblast, suggesting that it is a good nanomolecule as a candidate to regulate the secretion of collagen on the bone and other nano material.
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Affiliation(s)
- Jong-Hwa Oh
- Department of Oral Histology and Developmental Biology, School of Dentistry, Chosun University, Gwangju, 501-759, Korea
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Shim JW, Lee K, Jeong MJ, Jung SC, Kim BH. Hyaluronic acid immobilization on the poly-allylamine coated nano-network TiO2 surface. J Nanosci Nanotechnol 2011; 11:7343-7346. [PMID: 22103192 DOI: 10.1166/jnn.2011.4860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Recently, biocompatibility report revealed that the TiO2 nano-network (TiO2 NT) structure has much higher cells colonization than the native TiO2 on Ti surface. In this study, we prepared the hyaluronic acid (HA) immobilized TiO2 NT layer by plasma surface modification and then evaluated biological behavior of MC3T3-E1 on the Ti, TiO2 NT and TiO2 NT/NH2/HA surface. The cell viability tests revealed slightly enhanced viability on the TiO2 NT/NH2/HA surfaces than on the untreated Ti surfaces.
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Affiliation(s)
- Jae-Won Shim
- Department of Dental Materials, School of Dentistry, Chosun University, Gwangju, 501-759, Korea
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25
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Choi BD, Jeong SJ, Wang G, Park JJ, Lim DS, Kim BH, Cho YI, Kim CS, Jeong MJ. Secretory leukocyte protease inhibitor is associated with MMP-2 and MMP-9 to promote migration and invasion in SNU638 gastric cancer cells. Int J Mol Med 2011; 28:527-34. [PMID: 21687932 DOI: 10.3892/ijmm.2011.726] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 05/13/2011] [Indexed: 11/06/2022] Open
Abstract
Secretory leukocyte protease inhibitor (SLPI) protects tissue from proteases, and promotes cell proliferation and healing during inflammatory response. SLPI is also overexpressed in gastric, lung and ovarian cancers, which accelerates the metastasis of cancer cells. Matrix metalloproteinases-2, -9 (MMP-2 and MMP-9) are overexpressed in high metastatic cancers, and promote the migration of cancer cells through collagen degradation. SLPI and MMP-2, -9 are critical factors in stimulating the metastatic processes but there are no reports of a direct correlation between these molecules. Therefore, this study examined the role of SLPI related to MMP-2 and MMP-9 using two gastric cancer cell lines, such as characterized non-metastatic SNU484 and highly metastatic SNU638 cells. SLPI, MMP-2 and MMP-9 mRNA and protein expression were higher in SNU638 cells than in SNU484 cells. In addition, the rate of cell migration and invasion was higher in the SNU638 cells than in SNU484 cells. Interestingly, after treatment with SLPI, the rate of migration and invasion was higher in the SNU484 cells than in the positive control (PC) SNU484 cells. The rate of migration was also higher in the SNU638 cells after SLPI treatment than in the SNU638 cells (PC) but the invasion rate was not changed. The expression and secretion of MMP-2 and MMP-9 as well the rate of cell migration and invasion were significantly lower in SLPI-siRNA transfected SNU638 cells (si-SLPI/SNU638) but higher in SLPI-treated SNU484 cells (SNU484 + SLPI). Strong Elk-1 phosphorylation was detected in SNU484 + SLPI and SNU638 cells but was barely detectable in SNU484 and si-SLPI/SNU638 cells. These results show that SLPI promotes the metastasis of SNU638 gastric cancer cells by increasing MMP-2 and MMP-9 expression through Elk-1 signaling, indicating its role as a signaling molecule not a protease inhibitor.
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Affiliation(s)
- Baik-Dong Choi
- Department of Oral Histology and Developmental Biology, Chosun University, Gwangju 501‑759, Republic of Korea
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Wang G, Lim DS, Choi BD, Park JJ, Jeong SJ, Kim JS, Kim JD, Park JS, Kim EK, Kim BH, Ham JH, Jeong MJ. Effect of secretory leukocyte protease inhibitor on migration and invasion of human KB oral carcinoma cells. Anim Cells Syst (Seoul) 2011. [DOI: 10.1080/19768354.2011.577573] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Jeong MJ, Kim CS, Park JC, Kim HJ, Ko YM, Park KJ, Jeong SJ, Endou H, Kanai Y, Lim DS, Kim DK. Differential expression of system L amino acid transporters during wound healing process in the skin of young and old rats. Biol Pharm Bull 2008; 31:395-9. [PMID: 18310899 DOI: 10.1248/bpb.31.395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
UNLABELLED In order to elucidate the role of the system L-type amino acid transporters (LATs) in the wound healing process of aged and young subjects, we investigated the expression of LAT1, LAT2 and their subunit 4F2hc in the skin healing process after artificial wounds of dorsal skin in the young and old rats. METHODS The 1 cm full-thickness incisional wounds were made through the skin and panniculus carnosus muscle. The wounds were harvested at days 1, 3, 5 and 7 post-wounding, the experimental controls were harvested the skin of rat without wounds and the various analyses were performed. RESULTS In young rats, gradually and noticeable wound healing was detected, however, in old rats, wound healing was found to be greatly delayed. In young rats, the expression of LAT1 was increased rapidly on the day 1 after wound induction, on the other hand, in old rats, the expression of LAT1 after wound induction was not different from the control group. In young rats, the expression of LAT2 after the induction of wound was not different from the control group, however in old rats, the expression of LAT2 on the day 1 of wound induction was rapidly elevated. CONCLUSION These results suggest that the LAT1 and LAT2 increase in the wound healing process after cell injury in young and old rats, respectively.
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Affiliation(s)
- Moon-Jin Jeong
- Oral Biology Research Institute and The Second Stage of BK21, Chosun University College of Dentistry, 375 Seosukdong, Dong-gu, Gwangju 501-759, Korea
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Shim KM, Choi SH, Jeong MJ, Kang SS. Effects of aucubin on the healing of oral wounds. In Vivo 2007; 21:1037-1041. [PMID: 18210752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Aucubin is an iridoid glycoside with a variety of pharmacological effects, such as antimicrobial and antiinflammatory, whilst also promoting dermal wound healing. This study examined the effects of 0.1% aucubin on oral wound healing. ICR male mice were divided into two groups: an untreated control group (n=18) and an aucubin-treated group (n=18). Saline or 0.1% aucubin solution was injected and artificial full thickness wounds were made on either side of the buccal mucosa. Specimens were taken on days 1, 3 and 5, and light microscopic examination and quantitative histological analysis were performed to determine the extent of re-epithelization, inflammatory cell infiltration and matrix formation. Re-epithelization and matrix formation of the aucubin-treated group occurred earlier than that of the control group. In addition, the number of inflammatory cells of the aucubin-treated group was fewer than that of the control group. In conclusion, aucubin may be useful for oral wound healing and can be applied as a topical agent to oral wounds.
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Affiliation(s)
- Kyung Mi Shim
- College of Veterinary Medicine, Chonnam National University, Gwangju, Republic of Korea
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Jung WW, Kim EM, Lee EH, Yun HJ, Ju HR, Jeong MJ, Hwang KW, Sul D, Kang HS. Formaldehyde exposure induces airway inflammation by increasing eosinophil infiltrations through the regulation of reactive oxygen species production. Environ Toxicol Pharmacol 2007; 24:174-182. [PMID: 21783807 DOI: 10.1016/j.etap.2007.05.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2006] [Revised: 04/29/2007] [Accepted: 05/01/2007] [Indexed: 05/31/2023]
Abstract
Formaldehyde (FA) is a well-known cytotoxic irritant to the airways, but the mechanism of airway inflammation due to FA has not been clarified. In the present study, C57BL/6 mice were exposed to two concentrations (5 and 10ppm) of FA for 6h/day, 5days/week, for 2 weeks. The FA-exposed mice had much higher number of CCR3(+) eosinophils than control mice, and showed upregulated gene expression of CC-chemokine receptor-3 (CCR3), eotaxin and intercellular adhesion molecules-1 (ICAM-1) as well as an increased expression of proinflammatory and Th2 cytokines, such as interleukin (IL)-1β, IL-4 and IL-5. In addition, FA exposure revealed a considerable increase in the serum levels of IgG1, IgG3, IgA and IgE compared to controls. Histopathological analysis of the lung tissues demonstrated eosinophils and mononuclear cell infiltration of the alveolar cell walls and alveolar spaces. Gene expression of thioredoxin (TRX), redox-regulating antioxidant proteins, was markedly suppressed in FA-exposed mice, and thereby intracellular ROS levels were increased along with increased FA concentration. These results were consistent with an increase in the number of CCR3-expressing eosinophils, and indicate that FA-induced ROS was generated from eosinophils recruited to the inflammatory sites of the airways.
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Affiliation(s)
- Woon-Won Jung
- MyGene Bioscience Institute, 202-16 Nonhyun-Dong, Sung-Ok Bldg., 5th Floor, Kangnam-Ku, Seoul 405-847, South Korea
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Park JC, Park JT, Son HH, Kim HJ, Jeong MJ, Lee CS, Dey R, Cho MI. The amyloid protein APin is highly expressed during enamel mineralization and maturation in rat incisors. Eur J Oral Sci 2007; 115:153-60. [PMID: 17451507 DOI: 10.1111/j.1600-0722.2007.00435.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This study investigated the expression and localization of APin (which was previously identified and cloned from a rat odontoblast cDNA library), during ameloblast differentiation in rat incisors, by using in situ hybridization and immunohistochemistry. The subcellular localization of APin varied during ameloblast differentiation, but was stage-specific. APin mRNA was not expressed in pre-ameloblasts, was weakly expressed in secretory ameloblasts, and was strongly expressed in maturation-stage ameloblasts as well as in the junctional epithelium attached to the enamel of erupted molars. In the maturation-stage ameloblasts, APin protein was conspicuous in the supranuclear area (Golgi complex) of smooth-ended ameloblasts as well as in both the supranuclear area and the ruffle end of ruffle-ended ameloblasts. During ameloblast-lineage cell culture, APin was expressed at a low level in the early stages of culture, but at a high level in the late stage of culture, which was equivalent to the maturation stage. APin protein was efficiently secreted from transfected cells in culture. Furthermore, its overexpression and inactivation caused an increase and decrease in matrix metalloproteinase-20 (MMP-20) and tuftelin expression, respectively. These findings indicate a functional role for APin in the mineralization and maturation of enamel that is mediated by the expression of MMP-20 and tuftelin.
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Affiliation(s)
- Joo-Cheol Park
- Department of Oral Histology, College of Dentistry, Chosun University, Gwang-Ju, Korea.
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Cho HJ, Baek KE, Saika S, Jeong MJ, Yoo J. Snail is required for transforming growth factor-beta-induced epithelial-mesenchymal transition by activating PI3 kinase/Akt signal pathway. Biochem Biophys Res Commun 2006; 353:337-43. [PMID: 17187756 DOI: 10.1016/j.bbrc.2006.12.035] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2006] [Accepted: 12/03/2006] [Indexed: 12/15/2022]
Abstract
Lens epithelial cells undergo epithelial-mesenchymal transition (EMT) after injury as in cataract extraction, leading to fibrosis of the lens capsule. We have previously shown that EMT of primary lens epithelial cells in vitro depends on TGF-beta expression and more specifically, on signaling via Smad3. In this report, we suggest phosphatidylinositol 3-OH kinase (PI3K)/Akt signaling is also necessary for TGF-beta-induced EMT in lens epithelial cells by showing that LY294002, an inhibitor of the p110 catalytic subunit of PI3K, blocked the expression of alpha-smooth muscle actin (alpha-SMA) and morphological changes. We also identify Snail as an effector of TGF-beta-induced EMT. Snail has been shown to be a mediator of EMT during metastasis of cancer. We show that Snail is an immediate-early response gene for TGF-beta and the proximal Snail promoter is activated by TGF-beta through the action of Smad2, 3, and 4. We show that antisense inhibition of Snail expression blocks TGF-beta-induced EMT and furthermore Akt activation. All of these findings suggest that Snail participates in TGF-beta-induced EMT by acting upstream of Akt activation.
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Affiliation(s)
- Hee Jun Cho
- Department of Microbiology/Research Institute of Life Science, Gyeongsang National University, Jinju 660-701, Republic of Korea
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Kim HJ, Choi YS, Jeong MJ, Kim BO, Lim SH, Kim DK, Kim CK, Park JC. Expression of UNCL during development of periodontal tissue and response of periodontal ligament fibroblasts to mechanical stress in vivo and in vitro. Cell Tissue Res 2006; 327:25-31. [PMID: 17004066 DOI: 10.1007/s00441-006-0304-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Accepted: 07/13/2006] [Indexed: 02/06/2023]
Abstract
Mutations in two genes, uncoordinated (unc) and uncoordinated-like (uncl), lead to a failure of mechanotransduction in Drosophila. UNCL, the human homolog of unc and uncl, is preferentially expressed in periodontal ligament (PDL) fibroblasts compared with gingival fibroblasts. However, the precise role of UNCL in the PDL remains unclear. The aim of the present study has been to examine whether mechanical stimuli modulate the expression of UNCL in the human PDL in vivo and in vitro and to examine the roles of UNCL in the development, regeneration, and repair of the PDL. We have investigated the expression pattern of UNCL during the development of periodontal tissue and the response of PDL fibroblasts to mechanical stress in vivo and in vitro. The expression of UNCL mRNA and protein increases with PDL fibroblast differentiation from the confluent to multilayer stage but slightly decreases on mineralized nodule formation. UNCL has also been localized in ameloblasts and adjacent cells, differentiating cementoblasts, and osteoblasts of the developing tooth. Strong distinct UNCL expression has further been observed in the differentiating cementoblasts of the tooth periodontium at the site of tension after orthodontic tooth movement. Application of cyclic mechanical stress on PDL fibroblasts increases the expression of UNCL mRNA. These results indicate that UNCL plays important roles in the development, differentiation, and maintenance of periodontal tissues and also suggest a potential role of UNCL in the mechanotransduction of PDL fibroblasts.
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Affiliation(s)
- Heung-Joong Kim
- Oral Biology Research Institute, College of Dentistry, Chosun University, Gwang-Ju, South Korea
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Jeong SJ, Park JC, Kim HJ, Bae CS, Yoon MH, Lim DS, Jeong MJ. Comparative fine structure of the epididymal spermatozoa from three Korean shrews with considerations on their phylogenetic relationships. BIOCELL 2006; 30:279-86. [PMID: 16972552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
This study examined the fine structures of epididymal spermatozoa on the lesser white-toothed shrew (Crocidura suaveolens), the Japanese white-toothed shrew (C. dsinezumi) and the big white-toothed shrew (C. lasiura) belonging to the subfamily Crocidurinae living in Korea. In the spermatozoa of C. suaveolens, the head has a large acrosome, a smooth inner acrosomal membrane and a wavy, finger-like, electron-dense apical body. The neck has a solid proximal centriole that is filled with electron-dense material. These results showed the spermatozoa of C. suaveolens possess the characteristics of both Crocidurinae and Soricinae. In C. dsinezumi and C. lasiura, the head has a large acrosome, a serrated inner acrosomal membrane and a common apical body. The neck has a fistulous proximal centriole with slightly dense electron granules. These results showed the typical characteristics of Crocidurinae. Although C. suaveolens belongs to the subfamily Crocidurinae, the spermatozoan morphology is different from C. dsinezumi and C. lasiurai because it has conserved characteristics of the subfamily Soricinae.
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Affiliation(s)
- Soon-Jeong Jeong
- Department of Oral Histology and Oral Biology Institute, College of Dentistry, Chosun University, Gwangju 501-759, Korea
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Jeong SJ, Kim SG, Yoo J, Han MY, Park JC, Kim HJ, Kang SS, Choi BD, Jeong MJ. Increased association of dynamin II with myosin II in ras transformed NIH3T3 cells. Acta Biochim Biophys Sin (Shanghai) 2006; 38:556-62. [PMID: 16894478 DOI: 10.1111/j.1745-7270.2006.00193.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Dynamin has been implicated in the formation of nascent vesicles through both endocytic and secretory pathways. However, dynamin has recently been implicated in altering the cell membrane shape during cell migration associated with cytoskeleton-related proteins. Myosin II has been implicated in maintaining cell morphology and in cellular movement. Therefore, reciprocal immunoprecipitation was carried out to identify the potential relationship between dynamin II and myosin II. The dynamin II expression level was higher when co-expressed with myosin II in Ras transformed NIH3T3 cells than in normal NIH3T3 cells. Confocal microscopy also confirmed the interaction between these two proteins. Interestingly, exposing the NIH3T3 cells to platelet-derived growth factor altered the interaction and localization of these two proteins. The platelet-derived growth factor treatment induced lamellipodia and cell migration, and dynamin II interacted with myosin II. Grb2, a 24 kDa adaptor protein and an essential element of the Ras signaling pathway, was found to be associated with dynamin II and myosin II gene expression in the Ras transformed NIH3T3 cells. These results suggest that dynamin II acts as an intermediate messenger in the Ras signal transduction pathway leading to membrane ruffling and cell migration.
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Affiliation(s)
- Soon-Jeong Jeong
- Department of Oral Histology, College of Dentistry, Chosun University, Gwangju 501-759, South Korea
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Bae CS, Oh DM, Bae JG, Kim JC, Kim SH, Kim SG, Jeong MJ, Kim YS, Lim SC. Ultrastructural changes of the gemifloxacin on Achilles tendon in immature rats: comparison with those of ciproxacin and ofloxacin. Basic Clin Pharmacol Toxicol 2006; 98:406-10. [PMID: 16623866 DOI: 10.1111/j.1742-7843.2006.pto_326.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Gemifloxacin is a synthetic fluoroquinolone antimicrobial agent that exhibits potent activity against most Gram-negative and Gram-positive organisms, and has a comparatively low chondrotoxic potential in immature animals. This study examined the effects of gemifloxacin on the Achilles tendons in immature Sprague-Dawley rats treated by oral intubation once daily for 5 consecutive days from postnatal week 4 onward at doses of 0 (vehicle), and 600 mg/kg body weight. Ofloxacin or ciprofloxacin were used for comparison. The Achilles tendon specimens were examined by electron microscopy. In comparison with the vehicle-treated controls, there were ultrastructural changes in all samples from the gemifloxacin-, ofloxacin-, and ciprofloxacin-treated rats. Degenerative changes were observed in the tenocytes, and the cells that detached from the extracellular matrix were recognizable. The degree of degenerative changes and the number of degenerated cells in the Achilles tendon were significantly higher in the treated group than in the control group. Moreover, among the quinolone-treated groups, these findings were most significant in the ofloxacin-treated group, and least significant in the gemifloxacin-treated group. It is unclear what these findings mean with respect to the possible risk in juvenile patients treated with gemifloxacin or other quinolones. However, these results show that gemifloxacin causes less changes in the connective tissue structures.
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Affiliation(s)
- Chun-Sik Bae
- College of Veterinary Medicine, Biotechnology Research Institute, Chonnam National University, Gwangju 500-757, Korea
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Kim HK, Kong MY, Jeong MJ, Han DC, Choi JD, Kim HY, Yoon KS, Kim JM, Son KH, Kwon BM. Investigation of cell cycle arrest effects of actinomycin D at G1 phase using proteomic methods in B104-1-1 cells. Int J Biochem Cell Biol 2005; 37:1921-9. [PMID: 15964235 DOI: 10.1016/j.biocel.2005.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Revised: 04/20/2005] [Accepted: 04/28/2005] [Indexed: 11/15/2022]
Abstract
Actinomycin D was previously reported as an inhibitor of Shc/Grb2 interaction in B104-1-1 cells. Actinomycin D arrested the cell cycle at the G1 phase at 1nM, which is about 10 times lower than the inhibition of Shc/Grb2 interactions in B104-1-1 cells. To evaluate other mechanisms of actinomycin D affected suppression of tumors and cell growth, except inhibition of Shc/Grb2 interactions, we examined the proteomic expression profile by proteomic technology. We found up-regulation of MEKK3 and down-regulation of Hsp70 expression from proteomic analysis, which is a very interesting observation because MEKK3 is strongly related with G1 arrest of cell cycle and Hsp70 is also involved in cell cycle regulation. These results indicate that the anti-tumor effects of actinomycin D is due to synergic effects of various proteins regulated by the compound including inhibition of the Shc/Grb2 interaction and other signaling pathways in the cytoplasm. Here we provide a mechanism-based explanation for growth inhibition by actinomycin D using proteomic technology. Thus, this approach may be a potentially useful method to reveal new mechanisms of active compounds or drugs with unknown cellular function.
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Affiliation(s)
- Hyae-Kyeong Kim
- Korea Research Institute of Bioscience and Biotechnology, Taejon
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Kim HK, Jeong MJ, Kong MY, Han MY, Son KH, Kim HM, Hong SH, Kwon BM. Inhibition of Shc/Grb2 protein-protein interaction suppresses growth of B104-1-1 tumors xenografted in nude mice. Life Sci 2005; 78:321-8. [PMID: 16146636 DOI: 10.1016/j.lfs.2005.04.067] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2005] [Accepted: 04/26/2005] [Indexed: 11/19/2022]
Abstract
Actinomycin D was revealed as an inhibitor of Shc/Grb2 interaction in cell lines from our recent study. Shc and Grb2 proteins are important molecules in Ras signaling pathways leading to cellular differentiation and proliferation, which require dramatic morphological changes. It was detected by transmission electron microscopy that actinomycin D induced significant changes in cellular ultrastructures of B104-1-1 cells and confirmed that the changes were due to inhibition of Shc/Grb2 interaction by actinomycin D rather than its inhibitory effect on transcription. Because actinomycin D was dispersed mainly in cytoplasm and Shc peptide (synthetic 13 amino acid tyrosine phosphorylated polypeptide) successfully displaced actinomycin D binding to its cellular targets while the other polypeptide from PDGF receptor could not. We examined the effect of actinomycin D on growth of B104-1-1 tumor xenografted in nude mice. Tumor growth was inhibited in vivo after treatment with this inhibitor. Efficacy was correlated with a reduction in the levels of Shc/Grb2 binding in excised tumors. These results suggest that actinomycin D inhibited Shc/Grb2 interaction in B104-1-1 tumor xenografted in nude mice.
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Affiliation(s)
- Hyae-Kyeong Kim
- Korea Research Institute of Bioscience and Biotechnology, 52 Uendong Yusung Taejon, 305-333, Republic of Korea
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Yoo J, Jeong MJ, Cho HJ, Oh ES, Han MY. Dynamin II interacts with syndecan-4, a regulator of focal adhesion and stress-fiber formation. Biochem Biophys Res Commun 2005; 328:424-31. [PMID: 15694365 DOI: 10.1016/j.bbrc.2004.12.179] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2004] [Indexed: 10/25/2022]
Abstract
Dynamin is a large mechanochemical GTPase that has been implicated in vesicle formation in multiple cellular compartments. It is believed that dynamin interacts with a variety of cellular proteins to constrict membranes. To identify potential intracellular proteins that interact with the PH domain of dynamin II, we carried out a yeast two-hybrid screen in which the PH domain of dynamin II was used as bait. The cell surface heparan sulfate proteoglycan syndecan-4 that acts in conjunction with integrins to promote the formation of actin stress fibers and focal adhesions was isolated as a binding partner for the PH domain of dynamin II. In vitro binding assays, immunoprecipitation, and confocal microscopy analysis confirmed the association of dynamin II with syndecan-4. Most dramatic finding of our study is that the cytoplasmic distribution of dynamin II and syndecan-4 changes in fibroblasts that have been stimulated to form the focal adhesions and stress fibers with LPA. In quiescent cells, dynamin II is evenly distributed in the cytoplasm and colocalizes with syndecan-4 near the nucleus. Upon treatment with LPA to induce focal adhesions and stress-fiber formation, dynamin II becomes markedly associated with syndecan-4 at focal adhesion sites. We further established the colocalization of syndecan-4 and dynamin with paxillin and actin as marker proteins for focal adhesions and stress fibers, respectively. All of these results suggest that the interaction between dynamin II and syndecan-4 is important in mediating focal adhesion and stress-fiber formation.
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Affiliation(s)
- Jiyun Yoo
- Department of Microbiology/Research Institute of Life Science, Gyeongsang National University, Jinju 660-701, Korea
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Angelov N, Moutsopoulos N, Jeong MJ, Nares S, Ashcroft G, Wahl SM. Aberrant mucosal wound repair in the absence of secretory leukocyte protease inhibitor. Thromb Haemost 2005; 92:288-97. [PMID: 15269824 DOI: 10.1160/th03-07-0446] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Secretory leukocyte protease inhibitor (SLPI) is a cationic serine protease inhibitor with anti-microbial and anti-inflammatory properties found in large quantities in mucosal fluids, including saliva. SLPI is expressed during cutaneous wound healing, however, its role in oral wound repair is unknown. We have used a novel approach involving a murine buccal mucosal acute wound model to investigate the role of SLPI in oral healing. In parallel to the observed cutaneous healing phenotype, an absence of SLPI results in markedly impaired oral wound healing associated with increased inflammation and raised elastase activity. Moreover, matrix deposition was decreased, while MMP activity was enhanced in the oral SLPI null wounds suggesting deregulated proteolysis. Intriguingly, regardless of genotype, reduced collagen deposition was observed in oral compared to dermal wounds, associated with reduced TGF-beta expression and decreased fibroblast collagen expression in vitro. We propose that SLPI is a pivotal endogenous factor necessary for optimal tissue repair including intra-oral wound healing. In addition, our model provides a unique opportunity to delineate the cellular and molecular mechanisms underlying the differences between dermal scarring and oral scar-free healing.
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Affiliation(s)
- Nikola Angelov
- Oral Infection and Immunity Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland 20892, USA
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Abstract
BACKGROUND Expression of the small peptide thymosin beta4 is associated with angiogenesis induction, accelerated wound healing, and the metastatic potential of tumor cells. However, little is known about the mechanism(s) by which thymosin beta4 promotes metastasis. METHODS Northern blot analysis and immunohistochemistry were used to examine thymosin beta4 expression in mouse melanoma B16 cell lines and in B16-F10 cells derived from metastatic mouse lung tumors, respectively. B16-F10 cells infected with adenoviruses containing a thymosin beta4 expression vector or an empty vector were injected subcutaneously and intravenously into C57BL/6 mice to evaluate tumor growth and metastatic potential, respectively. In vitro assays were used to study cell migration, invasion, matrix metalloproteinase activity, cell proliferation, and angiogenic activity of adenovirus-infected B16-F10 cells. Statistical significance of all results was analyzed by two-tailed Student's t tests. RESULTS Thymosin beta4 mRNA was expressed in primary cultured B16-F10 cells derived from lung metastases and in B16-F10 cells that had formed lung tumors after being injected into mice but not in the B16-F1, B16-F10, or B16-BL6 cell lines. The mean tumor sizes in mice 20 days after injection with B16-F10 cells infected with thymosin beta4-expressing adenovirus and with control adenovirus were 21.7 mm (95% confidence interval [CI] = 17.7 to 25.7 mm) and 13.3 mm (95% CI = 11.1 to 15.3 mm), respectively (difference = 8.4 mm; P =.036). The mean numbers of metastatic lung nodules in mice (n = 20) 2 weeks after intravenous injection with thymosin beta4-expressing adenovirus and with control adenovirus were 46.7 (95% CI = 35.0 to 57.7) and 10.9 (95% CI = 6.2 to 15.6), respectively (difference = 35.8 metastatic lung nodules, P<.001). Thymosin beta4 overexpression was associated with a mean 2.3-fold increase (95% CI = 1.9- to 2.7-fold increase; P<.001) in B16-F10 cell migration and a mean 4.4-fold increase (95% CI = 3.3- to 5.5-fold increase; P<.001) in the number of blood vessels in solid tumors derived from injected B16-F10 cells but had no effect on cell invasion, proliferation, or matrix metalloproteinase activity. This induction of angiogenesis by thymosin beta4 was associated with induction of vascular endothelial growth factor expression. CONCLUSION Thymosin beta4 may stimulate tumor metastasis by activating cell migration and angiogenesis.
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Affiliation(s)
- Hee-Jae Cha
- Craniofacial Developmental Biology and Regeneration Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
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Ashcroft GS, Mills SJ, Lei K, Gibbons L, Jeong MJ, Taniguchi M, Burow M, Horan MA, Wahl SM, Nakayama T. Estrogen modulates cutaneous wound healing by downregulating macrophage migration inhibitory factor. J Clin Invest 2003; 111:1309-18. [PMID: 12727922 PMCID: PMC154440 DOI: 10.1172/jci16288] [Citation(s) in RCA: 211] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Characteristic of both chronic wounds and acute wounds that fail to heal are excessive leukocytosis and reduced matrix deposition. Estrogen is a major regulator of wound repair that can reverse age-related impaired wound healing in human and animal models, characterized by a dampened inflammatory response and increased matrix deposited at the wound site. Macrophage migration inhibitory factor (MIF) is a candidate proinflammatory cytokine involved in the hormonal regulation of inflammation. We demonstrate that MIF is upregulated in a distinct spatial and temporal pattern during wound healing and its expression is markedly elevated in wounds of estrogen-deficient mice as compared with intact animals. Wound-healing studies in mice rendered null for the MIF gene have demonstrated that in the absence of MIF, the excessive inflammation and delayed-healing phenotype associated with reduced estrogen is reversed. Moreover, in vitro assays have shown a striking estrogen-mediated decrease in MIF production by activated murine macrophages, a process involving the estrogen receptor. We suggest that estrogen inhibits the local inflammatory response by downregulating MIF, suggesting a specific target for future therapeutic intervention in impaired wound-healing states.
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Affiliation(s)
- Gillian S Ashcroft
- School of Biological Sciences, University of Manchester, Manchester, United Kingdom.
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Kim A, Kim KD, Choi SC, Jeong MJ, Lee HG, Choe YK, Paik SG, Lim JS. IL-12 Production and Subsequent Natural Killer Cell Activation by Necrotic Tumor Cell-loaded Dendritic Cells in Therapeutic Vaccinations. Immune Netw 2003. [DOI: 10.4110/in.2003.3.3.188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Affiliation(s)
- Aeyung Kim
- Laboratory of Cell Biology, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea
| | - Kwang Dong Kim
- Laboratory of Cell Biology, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea
| | - Seung-Chul Choi
- Laboratory of Cell Biology, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea
| | - Moon-Jin Jeong
- Department of Oral Histology, College of Dentistry, Chosun University, Gwangju, Korea
| | - Hee Gu Lee
- Laboratory of Cell Biology, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea
| | - Yong-Kyung Choe
- Laboratory of Cell Biology, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea
| | - Sang-Gi Paik
- Department of Biology, Chungnam National University, Daejeon, Korea
| | - Jong-Seok Lim
- Laboratory of Cell Biology, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea
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Yoo J, Jeong MJ, Kwon BM, Hur MW, Park YM, Han MY. Activation of dynamin I gene expression by Sp1 and Sp3 is required for neuronal differentiation of N1E-115 cells. J Biol Chem 2002; 277:11904-9. [PMID: 11809758 DOI: 10.1074/jbc.m111788200] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dynamin I is a key molecule required for the recycling of synaptic vesicles in neurons, and it has been known that dynamin I gene expression is induced during neuronal differentiation. Our previous studies established that neuronal restriction of dynamin I gene expression is controlled by Sp1 and nuclear factor-kappaB-like element-1. Here, using a series of deletion constructs and site-directed mutation, we found that transcription of dynamin I gene during neuronal differentiation of N1E-115 cells is controlled primarily by the Sp1 element located between -13 to -4 bp of the dynamin I promoter. Gel shift analysis demonstrated that in addition to Sp1, Sp3 could interact with this Sp1 element. The requirement for Sp family transcription factors in dynamin I gene expression was confirmed by using mithramycin, an inhibitor of Sp1/Sp3 binding. Mithramycin repressed dynamin I gene expression and resulted in blocking of neuronal differentiation of N1E-115 cells. The localization of the dynamin I protein was also restricted in the peripheral region of the nucleus by the mithramycin treatment. Thus, all of our results suggest that induction of dynamin I gene expression during N1E-115 cell differentiation is modulated by Sp1/Sp3 interactions with the dynamin I promoter, and its expression is important for neuronal differentiation of the N1E-115 cells.
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Affiliation(s)
- Jiyun Yoo
- Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Taejon 305-600, Korea
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Yoon SY, Jeong MJ, Yoo J, Lee KI, Kwon BM, Lim DS, Lee CE, Park YM, Han MY. Grb2 dominantly associates with dynamin II in human hepatocellular carcinoma HepG2 cells. J Cell Biochem 2002; 84:150-5. [PMID: 11746524 DOI: 10.1002/jcb.1275] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The two SH3 domains and one SH2 domain containing adaptor protein Grb2 is an essential element of the Ras signaling pathway in multiple systems. The SH2 domain of Grb2 recognizes and interacts with phosphotyrosine residues on activated tyrosine kinases, whereas the SH3 domains bind to several proline-rich domain-containing proteins such as Sos1. To define the difference in Grb2-associated proteins in hepatocarcinoma cells, we performed coprecipitation analysis using recombinant GST-Grb2 fusion proteins and found that several protein components (p170, p125, p100, and p80) differently associated with GST-Grb2 proteins in human Chang liver and hepatocarcinoma HepG2 cells. Sos1 and p80 proteins dominantly bind to Grb2 fusion proteins in Chang liver, whereas p100 remarkably associate with Grb2 in HepG2 cells. Also GST-Grb2 SH2 proteins exclusively bound to the p46(Shc), p52(Shc), and p66(Shc) are important adaptors of the Ras pathway in HepG2 cells. The p100 protein has been identified as dynamin II. We observed that the N-SH3 and C-SH3 domains of Grb2 fusion proteins coprecipitated with dynamin II besides Sos1. These results suggest that dynamin II may be a functional molecule involved in Grb2-mediated signaling pathway on Ras activation for tumor progression and differentiation of hepatocarcinoma cells.
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Affiliation(s)
- S Y Yoon
- Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, P.O. Box 115, Yusung, Taejon 305-600, Korea
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Jeong MJ, Park SC, Byun MO. Improvement of salt tolerance in transgenic potato plants by glyceraldehyde-3 phosphate dehydrogenase gene transfer. Mol Cells 2001; 12:185-9. [PMID: 11710519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
In the previous experiment, we isolated and characterized glyceraldehyde-3-phosphate dehydrogenase (GPD) gene of the oyster mushroom, Pleurotus sajor-caju. Expression levels of the GPD gene in the mycelia of P sajor-caju was significantly increased by exposing the mycelia to abiotic stresses, such as salt, cold, heat, and drought. We also showed that GPD confers abiotic stress resistance when introduced into yeast cells. The survival rate of the transgenic yeast cell that harbored the GPD gene was significantly higher when the yeast cells were subjected to salt, cold, heat, and drought stresses, compared with the yeast that was transformed with the pYES2 vector alone. In order to investigate the functional role of the P. sajor-caju GPD gene in higher plant cells, the complete P. sajor-caju GPD cDNA was fused into the CaMV35S promoter and then introduced into potato plants. Putative potato transformants were screened by using PCR. Twenty-one transformants were further analyzed with RT-PCR to confirm the expression of P. sajor-caju GPD. A RT-PCR Southern blot analysis revealed that 12 transgenics induced the P. sajor-caju GPD gene expression. A bioassay of these transformants revealed that the P. sajor-caju GPD gene was enough to confer salt stress resistance in the potato plant cell system. Results showed that P. sajor-caju GPD, which was continuously expressed in transgenic potato plants under normal growing conditions, resulted in improved tolerance against salt loading.
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Affiliation(s)
- M J Jeong
- Division of Molecular Genetics, National Institute of Agricultural Science and Technology, Rural Development Administration, Suwon, Korea.
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Namkung Y, Skrypnyk N, Jeong MJ, Lee T, Lee MS, Kim HL, Chin H, Suh PG, Kim SS, Shin HS. Requirement for the L-type Ca(2+) channel alpha(1D) subunit in postnatal pancreatic beta cell generation. J Clin Invest 2001; 108:1015-22. [PMID: 11581302 PMCID: PMC200955 DOI: 10.1172/jci13310] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Pancreatic beta cells are the source of insulin, which directly lowers blood glucose levels in the body. Our analyses of alpha(1D) gene-knockout (alpha(1D)(-/-)) mice show that the L-type calcium channel, alpha(1D), is required for proper beta cell generation in the postnatal pancreas. Knockout mice were characteristically slightly smaller than their littermates and exhibited hypoinsulinemia and glucose intolerance. However, isolated alpha(1D)(-/-) islets persisted in glucose sensing and insulin secretion, with compensatory overexpression of another L-type channel gene, alpha(1C). Histologically, newborn alpha(1D)(-/-) mice had an equivalent number of islets to wild-type mice. In contrast, adult alpha(1D)(-/-) mice showed a decrease in the number and size of islets, compared with littermate wild-type mice due to a decrease in beta cell generation. TUNEL staining showed that there was no increase in cell death in alpha(1D)(-/-) islets, and a 5-bromo-2' deoxyuridine-labeling (BrdU-labeling) assay illustrated significant reduction in the proliferation rate of beta cells in alpha(1D)(-/-) islets.
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Affiliation(s)
- Y Namkung
- National Creative Research Initiatives Center for Calcium and Learning, Pohang University of Science and Technology, Pohang, Korea
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Kim D, Song I, Keum S, Lee T, Jeong MJ, Kim SS, McEnery MW, Shin HS. Lack of the burst firing of thalamocortical relay neurons and resistance to absence seizures in mice lacking alpha(1G) T-type Ca(2+) channels. Neuron 2001; 31:35-45. [PMID: 11498049 DOI: 10.1016/s0896-6273(01)00343-9] [Citation(s) in RCA: 420] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
T-type Ca(2+) currents have been proposed to be involved in the genesis of spike-and-wave discharges, a sign of absence seizures, but direct evidence in vivo to support this hypothesis has been lacking. To address this question, we generated a null mutation of the alpha(1G) subunit of T-type Ca(2+) channels. The thalamocortical relay neurons of the alpha(1G)-deficient mice lacked the burst mode firing of action potentials, whereas they showed the normal pattern of tonic mode firing. The alpha(1G)-deficient thalamus was specifically resistant to the generation of spike-and-wave discharges in response to GABA(B) receptor activation. Thus, the modulation of the intrinsic firing pattern mediated by alpha(1G) T-type Ca(2+) channels plays a critical role in the genesis of absence seizures in the thalamocortical pathway.
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Affiliation(s)
- D Kim
- National Creative Research Initiative Center, for Calcium and Learning, Department of Life Science, Pohang University of Science and Technology, 790-784, Pohang, South Korea.
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Yoo J, Jeong MJ, Lee SS, Lee KI, Kwon BM, Park YM, Han MY. Negative regulation of YY1 transcription factor on the dynamin I gene promoter. Biochem Biophys Res Commun 2001; 283:340-3. [PMID: 11327704 DOI: 10.1006/bbrc.2001.4784] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dynamin I is highly expressed in brain and plays a critical role in clathrin-mediated endocytosis and synaptic vesicle recycling. To elucidate the molecular mechanism by which expression of dynamin I is tissue-specifically regulated, we previously cloned and characterized the promoter of the mouse dynamin I gene and suggested that there is a negative regulatory element in this promoter region. In the present study, we showed that YY1 binds to this negative regulatory element located at -111 to -107 by using the EMSA and supershift analyses. Cotransfection experiment using an YY1 expression vector revealed that YY1 exerts a repressive role on the dynamin I gene promoter activity. These results demonstrate that transcription factor YY1 negatively regulates dynamin I expression via binding to the negative regulatory element.
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Affiliation(s)
- J Yoo
- Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Taejon, Yusung, 305-600, Korea
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Yoo J, Jeong MJ, Lee SS, Lee KI, Kwon BM, Kim DS, Park YM, Han MY. The Neuron Restrictive Silencer Factor Can Act as an Activator for Dynamin I Gene Promoter Activity in Neuronal Cells. Biochem Biophys Res Commun 2001; 283:928-32. [PMID: 11350074 DOI: 10.1006/bbrc.2001.4857] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The neuron restrictive silencer element (NRSE) has been identified in several neuronal genes and confers neuron specificity by silencing transcription in nonneuronal cells. We have previously reported that Sp1 and an NF-kappaB-like element (NE-1) are required for the promoter activity of mouse dynamin I gene. In the present study, we found that the upstream regulatory region of the dynamin I promoter has an NRSE-like sequence and showed that neuron restrictive silencer factor (NRSF) binds to this element in neuronal cells as well as in nonneuronal cells. We also showed that NRSF activates the promoter activity of dynamin I gene in neuronal cells. From the results in this study, we suggest that NRSE might be involved in the neuron restriction of dynamin I expression, and NRSF could act as an activator for promoter activity of dynamin I gene in neuronal cells.
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Affiliation(s)
- J Yoo
- Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Yusung, Taejon, 305-600, Korea
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Jeong MJ, Yoo J, Lee SS, Lee KI, Cho A, Kwon BM, Moon MJ, Park YM, Han MY. Increased GTP-binding to dynamin II does not stimulate receptor-mediated endocytosis. Biochem Biophys Res Commun 2001; 283:136-42. [PMID: 11322780 DOI: 10.1006/bbrc.2001.4681] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Regarding the molecular mechanism of dynamin in receptor-mediated endocytosis, GTPase activity of dynamin has been thought to have a critical role in endocytic vesicle internalization. However, a recent report suggested that GTP-binding to dynamin itself activates the dynamin to recruit molecular machinery necessary for endocytosis. In this study, to investigate the role of GTP binding to dynamin II, we generated two mutant dynamin II constructs: G38V and K44E. G38V, its GTP binding site might be mainly occupied by GTP caused by reduced GTPase activity, and K44E mutant, its GTP binding site might be vacant, caused by its decreased affinity for GTP and GDP. From the analysis of the ratio of GTP vs GDP bound to dynamin, we confirmed these properties. To test the effect of these mutant dynamins on endocytosis, we performed flow cytometry and confocal immunofluorescence analysis and found that these two mutants have inhibitory effect on transferrin-induced endocytosis. Whereas fluorescent transferrin was completely internalized in wild-type (WT) dynamin II expressing cells, no intracellular accumulation of fluorescent transferrin was found in the cells overexpressing K44E and G38V mutant. Interestingly, the amount of GTP bound to K44E was increased when endocytosis was induced than that bound to WT. The present results suggested that the GTPase activity of dynamin II is required for formation of endocytic vesicle and GTP-binding to dynamin II per se is not sufficient for stimulating endocytosis.
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Affiliation(s)
- M J Jeong
- Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Taejon, Yusung, 305-600, Korea
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