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Yun N, Nah J, Lee MN, Wu D, Pae M. Post-Effects of Time-Restricted Feeding against Adipose Tissue Inflammation and Insulin Resistance in Obese Mice. Nutrients 2023; 15:2617. [PMID: 37299580 PMCID: PMC10255447 DOI: 10.3390/nu15112617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/31/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023] Open
Abstract
Time-restricted feeding (TRF) has been shown to improve the disordered metabolic and immunologic functions associated with obesity, however little is known about its post-effects after the cessation of TRF practice. In the current study, we determined how long the effects of TRF persist, and whether the effects are tissue-dependent. There were four groups of mice in this study: overweight and obese mice were randomized into (1) TRF group (TRF for 6 weeks), (2) post-TRF group (TRF for 4 weeks and later ad libitum), (3) continuous ad libitum of high-fat diet (HFD-AL), and (4) the lean control-fed low-fat diet ad libitum. Blood, liver, and adipose tissues were collected to measure the metabolic, inflammatory, and immune cell parameters. The results showed that TRF withdrawal quickly led to increased body weight/adiposity and reversed fasting blood glucose. However, fasting insulin and insulin resistance index HOMA-IR remained lower in the post-TRF than in the HFD-AL group. In addition, TRF-induced reduction in blood monocytes waned in the post-TRF group, but the TRF effects on mRNA levels of proinflammatory immune cells (macrophages Adgre1 and Itgax) and cytokine (Tnf) in adipose tissue remained lower in the post-TRF group than in the HFD-AL group. Furthermore, the TRF group was protected from the down-regulation of Pparg mRNA expression in adipose tissue, which was also observed in the post-TRF group to a lesser extent. The post-TRF animals displayed liver mass similar to those in the TRF group, but the TRF effects on the mRNA of inflammation markers in the liver vanished completely. Together, these results indicate that, although the lasting effects of TRF may differ by tissues and genes, the impact of TRF on adipose tissue inflammation and immune cell infiltration could last a couple of weeks, which may, in part, contribute to the maintenance of insulin sensitivity even after the cessation of TRF.
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Affiliation(s)
- Narae Yun
- Department of Food and Nutrition, Chungbuk National University, Chungdae-ro 1, Seowon-gu, Cheongju 28644, Republic of Korea; (N.Y.); (J.N.)
| | - Jiyeon Nah
- Department of Food and Nutrition, Chungbuk National University, Chungdae-ro 1, Seowon-gu, Cheongju 28644, Republic of Korea; (N.Y.); (J.N.)
| | - Mi Nam Lee
- Department of Biological Sciences, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea;
| | - Dayong Wu
- Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, 711 Washington Street, Boston, MA 02111, USA;
| | - Munkyong Pae
- Department of Food and Nutrition, Chungbuk National University, Chungdae-ro 1, Seowon-gu, Cheongju 28644, Republic of Korea; (N.Y.); (J.N.)
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2
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Kim Y, Lee Y, Lee MN, Nah J, Yun N, Wu D, Pae M. Time-restricted feeding reduces monocyte production by controlling hematopoietic stem and progenitor cells in the bone marrow during obesity. Front Immunol 2022; 13:1054875. [PMID: 36569870 PMCID: PMC9771705 DOI: 10.3389/fimmu.2022.1054875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 11/15/2022] [Indexed: 12/12/2022] Open
Abstract
Time-restricted feeding (TRF) has emerged as a promising dietary approach in improving metabolic parameters associated with obesity, but its effect on immune cells under obesogenic condition is poorly understood. We conducted this study to determine whether TRF exerts its therapeutic benefit over obesity-induced myeloid cell production by analyzing hematopoietic stem and progenitor cells in bone marrow (BM) and immune cell profile in circulation. Male C57BL/6 mice were fed a low-fat diet (LFD) or high-fat diet (HFD) ad libitum for 6 weeks and later a subgroup of HFD mice was switched to a daily 10 h-TRF schedule for another 6 weeks. Mice on HFD ad libitum for 12 weeks had prominent monocytosis and neutrophilia, associated with expansion of BM myeloid progenitors, such as multipotent progenitors, pre-granulocyte/macrophage progenitors, and granulocyte/macrophage progenitors. TRF intervention in overweight and obese mice diminished these changes to a level similar to those seen in mice fed LFD. While having no effect on BM progenitor cell proliferation, TRF reduced expression of Cebpa, a transcription factor required for myeloid differentiation. These results indicate that TRF intervention may help maintain immune cell homeostasis in BM and circulation during obesity, which may in part contribute to health benefits associated with TRF.
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Affiliation(s)
- Yelim Kim
- Department of Food and Nutrition, Chungbuk National University, Cheongju, Republic of Korea
| | - Youngyoon Lee
- Department of Food and Nutrition, Chungbuk National University, Cheongju, Republic of Korea
| | - Mi Nam Lee
- Department of Biological Sciences, Chonnam National University, Gwangju, Republic of Korea
| | - Jiyeon Nah
- Department of Food and Nutrition, Chungbuk National University, Cheongju, Republic of Korea
| | - Narae Yun
- Department of Food and Nutrition, Chungbuk National University, Cheongju, Republic of Korea
| | - Dayong Wu
- Nutritional Immunology Laboratory, Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, United States
| | - Munkyong Pae
- Department of Food and Nutrition, Chungbuk National University, Cheongju, Republic of Korea,*Correspondence: Munkyong Pae,
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3
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Song JH, Kim JW, Lee MN, Oh SH, Piao X, Wang Z, Kwon SH, Kim OS, Koh JT. Isolation of High Purity Mouse Mesenchymal Stem Cells through Depleting Macrophages Using Liposomal Clodronate. Tissue Eng Regen Med 2022; 19:565-575. [PMID: 34973125 PMCID: PMC9130445 DOI: 10.1007/s13770-021-00412-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 07/28/2021] [Revised: 10/20/2021] [Accepted: 11/07/2021] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND: The use of mouse bone marrow mesenchymal stem cells (mBMSCs) represents a promising strategy for performing preclinical studies in the field of cell-based regenerative medicine; however, mBMSCs obtained via conventional isolation methods have two drawbacks, i.e., (i) they are heterogeneous due to frequent macrophage contamination, and (ii) they require long-term culturing for expansion. METHODS: In the present study, we report a novel strategy to generate highly pure mBMSCs using liposomal clodronate. This approach is based on the properties of the two cell populations, i.e., BMSCs (to adhere to the plasticware in culture dishes) and macrophages (to phagocytose liposomes). RESULTS: Liposomal clodronate added during the first passage of whole bone marrow culture was selectively engulfed by macrophages in the heterogeneous cell population, resulting in their effective elimination without affecting the MSCs. This method allowed the generation of numerous high-purity Sca-1+CD44+F4/80− mBMSCs (> 95%) with just one passaging. Comparative studies with mBMSCs obtained using conventional methods revealed that the mBMSCs obtained in the present study had remarkably improved experimental utilities, as demonstrated by in vitro multilineage differentiation and in vivo ectopic bone formation assays. CONCLUSION: Our newly developed method, which enables the isolation of mBMSCs using simple and convenient protocol, will aid preclinical studies based on the use of MSCs. Supplementary Information The online version contains supplementary material available at 10.1007/s13770-021-00412-6.
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Affiliation(s)
- Ju Han Song
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Jung-Woo Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Mi Nam Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Sin-Hye Oh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Xianyu Piao
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Zhao Wang
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Seung-Hee Kwon
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Ok-Su Kim
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.,Department of Periodontology, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Jeong-Tae Koh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea. .,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.
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4
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Lee MN, Lee Y, Wu D, Pae M. Luteolin inhibits NLRP3 inflammasome activation via blocking ASC oligomerization. J Nutr Biochem 2021; 92:108614. [PMID: 33705947 DOI: 10.1016/j.jnutbio.2021.108614] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/26/2020] [Accepted: 02/02/2021] [Indexed: 01/12/2023]
Abstract
The NLRP3 inflammasome is a caspase-1 containing multi-protein complex that controls the release of IL-1β and plays important roles in the innate immune response. Since NLRP3 inflammasome is implicated in the pathogenesis of a variety of diseases, it has become an increasingly interested target in developing therapies for multiple diseases. We reported the current study to determine how luteolin, a natural phenolic compound found in many vegetables and medicinal herbs, would modulate NLRP3 inflammasome in both the in vivo and in vitro settings. First, we found that a high-fat diet upregulated mRNA expression of NLRP3 inflammasome components Asc and Casp1 in adipose tissue of ovariectomized mice, which were greatly reduced by dietary supplementation with luteolin. Of note, Asc and Casp1 expression in adipose tissue correlated with mRNA levels of Adgre1 encoding F4/80, an established marker for mature macrophages. We also demonstrated that luteolin inhibited NLRP3 inflammasome-derived caspase-1 activation and IL-1β secretion in J774A.1 macrophages upon diverse stimuli including ATP, nigericin, or silica crystals. Luteolin inhibited the activation step of NLRP3 inflammasome by interfering with ASC oligomerization. Taken together, these findings suggest that luteolin supplementation may suppress NLRP3 induction and activation process and thus potentially would be protective against NLRP3-mediated inflammatory diseases.
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Affiliation(s)
- Mi Nam Lee
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Youngyoon Lee
- Department of Food and Nutrition, Chungbuk National University, Chundae-ro 1, Seowon-gu, Cheongju, Republic of Korea
| | - Dayong Wu
- Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts, USA
| | - Munkyong Pae
- Department of Food and Nutrition, Chungbuk National University, Chundae-ro 1, Seowon-gu, Cheongju, Republic of Korea.
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Jeong BC, Oh SH, Lee MN, Koh JT. Macrophage-Stimulating Protein Enhances Osteoblastic Differentiation via the Recepteur d'Origine Nantais Receptor and Extracellular Signal-Regulated Kinase Signaling Pathway. J Bone Metab 2020; 27:267-279. [PMID: 33317230 PMCID: PMC7746481 DOI: 10.11005/jbm.2020.27.4.267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 10/26/2020] [Indexed: 12/12/2022] Open
Abstract
Background Macrophage-stimulating protein (MSP; also known as macrophage stimulating 1 and hepatocyte growth factor-like protein) has been shown to play a crucial role in calcium homeostasis and skeletal mineralization in zebrafish. However, the precise role of MSP in osteoblasts has not been elucidated. In this study, we investigated the effect of MSP on osteoblast differentiation of pre-osteoblast cells. Methods Osteoblast differentiation upon MSP treatment was evaluated by analyzing the osteogenic gene expression, alkaline phosphatase (ALP) activity, and mineralized nodule formation. To assess changes in the MSP-RON signaling pathway, knockdown of Ron gene was performed using siRNA and pharmacological inhibitor treatment. Results Expression of the tyrosine kinase receptor RON, a receptor of MSP, was found to be significantly increased during osteoblast differentiation. MSP treatment significantly upregulated the expression of osteogenic marker genes and remarkably increased ALP activity and mineralized nodule formation. Conversely, knockdown of Ron significantly attenuated the expression of osteogenic marker genes and ALP activity that were induced upon MSP treatment. Mechanistically, MSP treatment significantly enhanced the phosphorylation of extracellular signal-regulated kinase (ERK); however, additional treatment with the selective ERK inhibitor PD98059 attenuated the effect of MSP on osteoblast differentiation. Conclusions Altogether, these results indicate that the MSP-RON axis is involved in promoting osteoblast differentiation via activation of the ERK signaling pathway.
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Affiliation(s)
- Byung-Chul Jeong
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Sin-Hye Oh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea.,Hard-Tissue Biointerface Research Center, Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Mi Nam Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea.,Hard-Tissue Biointerface Research Center, Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Jeong-Tae Koh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea.,Hard-Tissue Biointerface Research Center, Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
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6
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Son HJ, Lee MN, Kim Y, Choi H, Jeong BC, Oh SH, Kim JW, Kwon SH, Kim SH, Song SC, Lee SE, Koh JT. Bone Generation Following Repeated Administration of Recombinant Bone Morphogenetic Protein 2. Tissue Eng Regen Med 2020; 18:155-164. [PMID: 33058016 DOI: 10.1007/s13770-020-00290-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [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: 02/13/2020] [Revised: 07/14/2020] [Accepted: 07/22/2020] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND The delivery of recombinant human bone morphogenetic protein 2 (rhBMP2) by using various carriers has been used to successfully induce bone formation in many animal models. However, the effect of multiple administration of rhBMP2 on bone formation and BMP2 antibody production has not been determined. Our aim was to examine the bone formation activity of rhBMP2 and serum levels of anti-BMP2 antibodies following the repeated administration of rhBMP2 in mice. METHODS Absorbable collagen sponges or polyphosphazene hydrogels containing rhBMP2 were subcutaneously implanted or injected into one side on the back of six-week-old C57BL/6 mice. Three or 4 weeks later, the same amount of rhBMP2 was administered again with the same carrier into the subcutaneous regions on the other side of the back or into calvarial defects. The effects of a single administration of rhBMP2 on the osteoinductive ability in the ectopic model were compared with those of repeated administrations. In vivo ectopic or orthotopic bone formation was evaluated using microradiography and histological analyses. Serum concentrations of anti-rhBMP2 antibodies were measured by ELISAs. RESULTS Re-administration of the same amount of rhBMP2 into the subcutaneous area showed a comparable production of ectopic bone as after the first administration. The bone forming ability of repeated rhBMP2 administrations was equal to that of single rhBMP2 administration. The administration of rhBMP2 into calvarial defects, following the first subcutaneous administration of rhBMP2 on the back, completely recovered the defect area with newly regenerated bone within 3 weeks. Repeated administration of rhBMP2 at 4-week intervals did not significantly alter the serum levels of anti-BMP2 antibodies and did not induce any inflammatory response. The serum obtained from rhBMP2-exposed mice had no effect on the ability of rhBMP2 to induce osteogenic gene expressions in MC3T3-E1. CONCLUSION We suggest that the osteoinductive ability of rhBMP2 is not compromised by repeated administrations. Thus, rhBMP2 can be repeatedly used for bone regeneration at various sites within a short duration.
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Affiliation(s)
- Hye-Ju Son
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Mi Nam Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.,Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Yuri Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Hyuck Choi
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Byung-Chul Jeong
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Sin-Hye Oh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.,Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Jung-Woo Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.,Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Seung-Hee Kwon
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.,Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Sun-Hun Kim
- Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.,Department of Oral Anatomy, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Soo-Chang Song
- Center for Biomaterials, Korea Institute of Science and Technology, 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Shee Eun Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.,Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Jeong-Tae Koh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea. .,Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, 33 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.
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7
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Zang Y, Song JH, Oh SH, Kim JW, Lee MN, Piao X, Yang JW, Kim OS, Kim TS, Kim SH, Koh JT. Targeting NLRP3 Inflammasome Reduces Age-Related Experimental Alveolar Bone Loss. J Dent Res 2020; 99:1287-1295. [PMID: 32531176 DOI: 10.1177/0022034520933533] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The cause of chronic inflammatory periodontitis, which leads to the destruction of periodontal ligament and alveolar bone, is multifactorial. An increasing number of studies have shown the clinical significance of NLRP3-mediated low-grade inflammation in degenerative disorders, but its causal linkage to age-related periodontitis has not yet been elucidated. In this study, we investigated the involvement of the NLRP3 inflammasome and the therapeutic potential of NLRP3 inhibition in age-related alveolar bone loss by using in vivo and in vitro models. The poor quality of alveolar bones in aged mice was correlated with caspase-1 activation by macrophages and elevated levels of IL-1β, which are mainly regulated by the NLRP3 inflammasome, in periodontal ligament and serum, respectively. Aged mice lacking Nlrp3 showed better bone mass than age-matched wild-type mice via a way that affects bone resorption rather than bone formation. In line with this finding, treatment with MCC950, a potent inhibitor of the NLRP3 inflammasome, significantly suppressed alveolar bone loss with reduced caspase-1 activation in aged mice but not in young mice. In addition, our in vitro studies showed that the addition of IL-1β encourages RANKL-induced osteoclastogenesis from bone marrow-derived macrophages and that treatment with MCC950 significantly suppresses osteoclastic differentiation directly, irrelevant to the inhibition of IL-1β production. Our results suggest that the NLRP3 inflammasome is a critical mediator in age-related alveolar bone loss and that targeting the NLRP3 inflammasome could be a novel option for controlling periodontal degenerative changes with age.
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Affiliation(s)
- Y Zang
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - J H Song
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - S H Oh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - J W Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - M N Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - X Piao
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - J W Yang
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - O S Kim
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Department of Periodontology, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - T S Kim
- Department of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - S H Kim
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Department of Oral Anatomy, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - J T Koh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.,Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
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8
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Lee MN, Song JH, Oh SH, Tham NT, Kim JW, Yang JW, Kim ES, Koh JT. The primary cilium directs osteopontin-induced migration of mesenchymal stem cells by regulating CD44 signaling and Cdc42 activation. Stem Cell Res 2020; 45:101799. [PMID: 32339903 DOI: 10.1016/j.scr.2020.101799] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 01/28/2020] [Accepted: 03/27/2020] [Indexed: 12/20/2022] Open
Abstract
The primary cilium acts as a sensory organelle with diverse receptors and ion channels to detect extracellular cues and regulate cellular functions, including cell migration. The migration of mesenchymal stem cells (MSCs) to bone remodeling sites is important for bone homeostasis. Recently, we have suggested that osteopontin (OPN) is a significant chemoattractant in MSC migration to bone remodeling sites. The objective of this study was to determine whether the primary cilium acts as a chemoattractant sensory unit to detect OPN cues and control MSC migration. We found that the loss of primary cilium induced by silencing of IFT88 reduced OPN-induced migration of MSCs. The effect of IFT88 silencing on cellular attachment, spreading, and proliferation was negligible. The loss of primary cilium did not affect the level of integrinβ1 or CD44, two known receptors for OPN. Interestingly, CD44 was localized to the primary cilium by OPN stimulus. Knockdown of IFT88 or CD44 dysregulated OPN-induced signaling activation and abolished OPN-induced Cdc42 activation. Our findings suggest that the primary cilium acts as a chemoattractant sensor for OPN to regulate MSC migration by controlling not only CD44-mediated OPN signaling, but also Cdc42-mediated actin cytoskeleton rearrangement.
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Affiliation(s)
- Mi Nam Lee
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Ju Han Song
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Sin-Hye Oh
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Nguyen Thi Tham
- Department of Biological Sciences and Biotechnology, Chonnam National University, Gwangju, Korea
| | - Jung-Woo Kim
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Jin-Woo Yang
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Eung-Sam Kim
- Department of Biological Sciences and Biotechnology, Chonnam National University, Gwangju, Korea
| | - Jeong-Tae Koh
- Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Korea.
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9
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Haines BM, Shah RC, Smidt JM, Albright BJ, Cardenas T, Douglas MR, Forrest C, Glebov VY, Gunderson MA, Hamilton CE, Henderson KC, Kim Y, Lee MN, Murphy TJ, Oertel JA, Olson RE, Patterson BM, Randolph RB, Schmidt DW. Observation of persistent species temperature separation in inertial confinement fusion mixtures. Nat Commun 2020; 11:544. [PMID: 31992703 PMCID: PMC6987117 DOI: 10.1038/s41467-020-14412-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [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] [Received: 08/05/2019] [Accepted: 12/17/2019] [Indexed: 11/09/2022] Open
Abstract
The injection and mixing of contaminant mass into the fuel in inertial confinement fusion (ICF) implosions is a primary factor preventing ignition. ICF experiments have recently achieved an alpha-heating regime, in which fusion self-heating is the dominant source of yield, by reducing the susceptibility of implosions to instabilities that inject this mass. We report the results of unique separated reactants implosion experiments studying pre-mixed contaminant as well as detailed high-resolution three-dimensional simulations that are in good agreement with experiments. At conditions relevant to mixing regions in high-yield implosions, we observe persistent chunks of contaminant that do not achieve thermal equilibrium with the fuel throughout the burn phase. The assumption of thermal equilibrium is made in nearly all computational ICF modeling and methods used to infer levels of contaminant from experiments. We estimate that these methods may underestimate the amount of contaminant by a factor of two or more.
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Affiliation(s)
- Brian M Haines
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA.
| | - R C Shah
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
- Laboratory for Laser Energetics, University of Rochester, 250 E. River Rd., Rochester, NY, 14623, USA
| | - J M Smidt
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - B J Albright
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - T Cardenas
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - M R Douglas
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - C Forrest
- Laboratory for Laser Energetics, University of Rochester, 250 E. River Rd., Rochester, NY, 14623, USA
| | - V Yu Glebov
- Laboratory for Laser Energetics, University of Rochester, 250 E. River Rd., Rochester, NY, 14623, USA
| | - M A Gunderson
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - C E Hamilton
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - K C Henderson
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - Y Kim
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - M N Lee
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - T J Murphy
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - J A Oertel
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - R E Olson
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - B M Patterson
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - R B Randolph
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
| | - D W Schmidt
- Los Alamos National Laboratory, P.O. Box 1663, MS T087, Los Alamos, NM, 87545, USA
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10
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Kim YH, Jang WG, Oh SH, Kim JW, Lee MN, Song JH, Yang JW, Zang Y, Koh JT. Fenofibrate induces PPARα and BMP2 expression to stimulate osteoblast differentiation. Biochem Biophys Res Commun 2019; 520:459-465. [PMID: 31607484 DOI: 10.1016/j.bbrc.2019.10.048] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [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: 09/20/2019] [Accepted: 10/03/2019] [Indexed: 10/25/2022]
Abstract
The peroxisome proliferator-activated receptor (PPAR)-α agonist fenofibrate is used as a lipid-lowering agent to reduce cholesterol and triglyceride in blood. In this study, we investigated whether fenofibrate affects osteoblast differentiation of osteogenic precursor cells. Quantitative real-time PCR and alkaline phosphatase (ALP) staining assays revealed that fenofibrate can enhance the osteoblast differentiation of C3H10T1/2 and MC3T3-E1 cells. In contrast with fenofibrate, the PPARγ agonist rosiglitazone decreased or did not affect the expression of osteogenic genes in these cells. Fenofibrate dose- and time-dependently increased PPARα expression, and concomitantly increased the expression of bone morphogenetic protein 2 (BMP2). Knockdown of PPARα abolished fenofibrate-induced BMP2 expression, activity of the BMP2 promoter gene, and calcium deposition. The chromatin immunoprecipitation assay demonstrated that fenofibrate increased BMP2 expression by inducing direct binding of PPARα to the BMP2 promoter region. Taken together, we suggest that fenofibrate has a stimulatory effect on osteoblast differentiation via the elevation of PPARα levels and the PPARα-mediated BMP2 expression. Our findings provide fenofibrate as a useful agent for controlling hypercholesterolemic patients with osteoporosis.
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Affiliation(s)
- Yu-Ha Kim
- Hard Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Won-Gu Jang
- Department of Biotechnology, School of Engineering, Daegu University, Gyeongsan, Republic of Korea
| | - Sin-Hye Oh
- Hard Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Jung-Woo Kim
- Hard Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Mi Nam Lee
- Hard Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Ju Han Song
- Hard Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Jin-Woo Yang
- Hard Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Yaran Zang
- Hard Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Jeong-Tae Koh
- Hard Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.
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11
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Baek Y, Lee MN, Wu D, Pae M. Luteolin reduces adipose tissue macrophage inflammation and insulin resistance in postmenopausal obese mice. J Nutr Biochem 2019; 71:72-81. [PMID: 31302373 DOI: 10.1016/j.jnutbio.2019.06.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [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: 01/19/2019] [Revised: 05/09/2019] [Accepted: 06/04/2019] [Indexed: 02/06/2023]
Abstract
Previously, we showed that loss of ovarian function in mice fed high-fat diet exacerbated insulin resistance and adipose tissue inflammation. In the current study, we tested whether consumption of luteolin, an anti-inflammatory flavonoid, could mitigate adipose tissue inflammation and insulin resistance in obese ovariectomized mice. Nine-week-old ovariectomized C57BL/6 mice were fed a low-fat diet, high-fat diet (HFD) or HFD supplemented with 0.005% luteolin (HFD+L) for 16 weeks. Results showed no difference in body weight or fat mass between mice fed HFD+L and those fed HFD. However, luteolin supplementation resulted in lower CD11c+ macrophages in gonadal adipose tissue, as well as a trend toward lower macrophage infiltration. Luteolin supplementation also significantly lowered mRNA expression of inflammatory and M1 markers MCP-1, CD11c, TNF-α and IL-6, while maintaining expression of M2 marker MGL1. Consistent with this, the in vitro luteolin treatment, with or without the presence of estrogen, inhibited lipopolysaccharide-induced polarization of RAW 264.7 cells toward M1 phenotype. We further found that luteolin supplementation protected mice from insulin resistance induced by HFD consumption; this improved insulin resistance was correlated with reductions in CD11c+ adipose tissue macrophages. Taken together, these findings indicate that dietary luteolin supplementation attenuates adipose tissue inflammation and insulin resistance found in mice with loss of ovarian function coupled with an HFD intake, and this effect may be partly mediated through suppressing M1-like polarization of macrophages in adipose tissue. These results have clinical implication in implementing dietary intervention for prevention of metabolic syndrome associated with postmenopause and obesity.
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Affiliation(s)
- Yunjung Baek
- Department of Food and Nutrition, Chungbuk National University, Chungdae-ro 1, Seowon-gu, Cheongju 28622, Republic of Korea
| | - Mi Nam Lee
- Research Center for Biomineralization Disorders, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Dayong Wu
- Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA
| | - Munkyong Pae
- Department of Food and Nutrition, Chungbuk National University, Chungdae-ro 1, Seowon-gu, Cheongju 28622, Republic of Korea.
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12
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Abstract
Abstract
Objectives
Previously, we showed that loss of ovarian function in mice fed high-fat diet exacerbated insulin resistance and adipose tissue inflammation. In the current study, we tested whether consumption of luteolin, an anti-inflammatory flavonoid, could mitigate adipose tissue inflammation and insulin resistance in obese ovariectomized mice.
Methods
Nine-week-old ovariectomized C57BL/6 mice were fed a low-fat diet (LFD), high-fat diet (HFD), or HFD supplemented with 0.005% luteolin (HFD + L) for 16 weeks. The anti-inflammatory drug salicylate was used as a positive control. Fasting blood glucose, insulin, and insulin resistance index HOMA-IR were measured every 4 weeks. Adipose tissue and spleen were characterized for tissue inflammation by real-time PCR and immune cell populations by flow cytometry after 16 weeks of feeding.
Results
HFD resulted in more body weight gain than LFD in ovariectomized mice and supplementing HFD with 0.005% luteolin did not affect the body weight gain. In addition, HFD elicited a significant elevation in fat mass, which were comparable between HFD and HFD + L groups. However, luteolin supplementation resulted in a significant decrease in CD11c+ macrophages in gonadal adipose tissue, as well as a trend of decrease in macrophage infiltration. Luteolin supplementation also significantly decreased mRNA expression of inflammatory and M1 markers MCP-1, CD11c, TNF-a, and IL-6, while maintaining expression of M2 marker MGL1. We further found that luteolin treatment protected mice from insulin resistance induced by HFD consumption; this improved insulin resistance was correlated with reductions in CD11c+ adipose tissue macrophages.
Conclusions
Our findings indicate that dietary luteolin supplementation attenuates adipose tissue inflammation and insulin resistance found in mice with loss of ovarian function coupled with a HFD intake, and this effect may be partly mediated through suppressing M1-like polarization of macrophages in adipose tissue. These results have clinical implication in implementing dietary intervention for prevention of metabolic syndrome associated with postmenopause and obesity.
Funding Sources
Supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (NRF-2018R1A1A1A05078886).
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Affiliation(s)
| | | | - Dayong Wu
- Nutritional Immunology Lab, JM USDA-HNRCA at Tufts University
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13
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Lee MN, Hwang HS, Oh SH, Roshanzadeh A, Kim JW, Song JH, Kim ES, Koh JT. Elevated extracellular calcium ions promote proliferation and migration of mesenchymal stem cells via increasing osteopontin expression. Exp Mol Med 2018; 50:1-16. [PMID: 30393382 PMCID: PMC6215840 DOI: 10.1038/s12276-018-0170-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/30/2018] [Accepted: 07/12/2018] [Indexed: 02/06/2023] Open
Abstract
Supplementation of mesenchymal stem cells (MSCs) at sites of bone resorption is required for bone homeostasis because of the non-proliferation and short lifespan properties of the osteoblasts. Calcium ions (Ca2+) are released from the bone surfaces during osteoclast-mediated bone resorption. However, how elevated extracellular Ca2+ concentrations would alter MSCs behavior in the proximal sites of bone resorption is largely unknown. In this study, we investigated the effect of extracellular Ca2+ on MSCs phenotype depending on Ca2+ concentrations. We found that the elevated extracellular Ca2+ promoted cell proliferation and matrix mineralization of MSCs. In addition, MSCs induced the expression and secretion of osteopontin (OPN), which enhanced MSCs migration under the elevated extracellular Ca2+ conditions. We developed in vitro osteoclast-mediated bone resorption conditions using mouse calvaria bone slices and demonstrated Ca2+ is released from bone resorption surfaces. We also showed that the MSCs phenotype, including cell proliferation and migration, changed when the cells were treated with a bone resorption-conditioned medium. These findings suggest that the dynamic changes in Ca2+ concentrations in the microenvironments of bone remodeling surfaces modulate MSCs phenotype and thereby contribute to bone regeneration.
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Affiliation(s)
- Mi Nam Lee
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Hee-Su Hwang
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Sin-Hye Oh
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Amir Roshanzadeh
- School of Biological Sciences and Biotechnology, Chonnam National University, Gwangju, Republic of Korea
| | - Jung-Woo Kim
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Ju Han Song
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Eung-Sam Kim
- Department of Biological Sciences, Chonnam National University, Gwangju, Republic of Korea
| | - Jeong-Tae Koh
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea.
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14
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Jeong H, Koh A, Lee J, Park D, Lee JO, Lee MN, Jo KJ, Tran HNK, Kim E, Min BS, Kim HS, Berggren PO, Ryu SH. Inhibition of C1-Ten PTPase activity reduces insulin resistance through IRS-1 and AMPK pathways. Sci Rep 2017; 7:17777. [PMID: 29259227 PMCID: PMC5736594 DOI: 10.1038/s41598-017-18081-8] [Citation(s) in RCA: 7] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 12/06/2017] [Indexed: 11/09/2022] Open
Abstract
Insulin resistance causes type 2 diabetes; therefore, increasing insulin sensitivity is a therapeutic approach against type 2 diabetes. Activating AMP-activated protein kinase (AMPK) is an effective approach for treating diabetes, and reduced insulin receptor substrate-1 (IRS-1) protein levels have been suggested as a molecular mechanism causing insulin resistance. Thus, dual targeting of AMPK and IRS-1 might provide an ideal way to treat diabetes. We found that 15,16-dihydrotanshinone I (DHTS), as a C1-Ten protein tyrosine phosphatase inhibitor, increased IRS-1 stability, improved glucose tolerance and reduced muscle atrophy. Identification of DHTS as a C1-Ten inhibitor revealed a new function of C1-Ten in AMPK inhibition, possibly through regulation of IRS-1. These findings suggest that C1-Ten inhibition by DHTS could provide a novel therapeutic strategy for insulin resistance-associated metabolic syndrome through dual targeting of IRS-1 and AMPK.
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Affiliation(s)
- Heeyoon Jeong
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Ara Koh
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Jiyoun Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Dohyun Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Jung Ok Lee
- Department of Anatomy, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Mi Nam Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Kyung-Jin Jo
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Huynh Nguyen Khanh Tran
- College of Pharmacy, Drug Research and Development Center, Catholic University of Daegu, Gyeongbuk, 38430, Republic of Korea
| | - Eui Kim
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Byung-Sun Min
- College of Pharmacy, Drug Research and Development Center, Catholic University of Daegu, Gyeongbuk, 38430, Republic of Korea
| | - Hyeon Soo Kim
- Department of Anatomy, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Per-Olof Berggren
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Karolinska University Hospital, S-171 76, Stockholm, Sweden
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea.
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea.
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15
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Oh SH, Kim JW, Kim Y, Lee MN, Kook MS, Choi EY, Im SY, Koh JT. The extracellular matrix protein Edil3 stimulates osteoblast differentiation through the integrin α5β1/ERK/Runx2 pathway. PLoS One 2017; 12:e0188749. [PMID: 29182679 PMCID: PMC5705136 DOI: 10.1371/journal.pone.0188749] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/12/2017] [Indexed: 02/07/2023] Open
Abstract
Epidermal growth factor-like repeats and discoidin I-like domain 3 (Edil3) is an extracellular matrix protein containing an Arg-Gly-Asp (RGD) motif that binds integrin. Recently, Edil3 has been implicated in various biological processes, including angiogenesis and cellular differentiation. It can inhibit inflammatory bone destruction. The objective of this study was to explore the role of Edil3 in osteoblast differentiation and its underlying molecular mechanisms. In wild-type mice, high expression levels of Edil3 mRNA were observed in isolated calvaria and tibia/femur bones. Immunohistochemical analysis showed that Edil3 protein was localized along periosteum and calcified regions surrounding bone tissues. When murine calvaria-derived MC3T3-E1 cells were cultured in osteogenic medium containing 50 μg/ml ascorbic acid and 5 mM β-glycerophosphate, Edil3 mRNA and protein expression levels were increased. Treatment with Edil3 protein in growth media increased expression levels of alkaline phosphatase and osteocalcin gene and phosphorylation level of extracellular signal-regulated kinase (ERK). Edil3 treatment with osteogenic medium induced mineralization. Treatment with a neutralizing antibody against α5β1 and MEK inhibitor U0126 inhibited Edil3-enhanced osteogenic marker gene expression and mineral deposition. Edil3 increased protein expression levels of transcription factor runt-related transcription factor2 (Runx2). Edil3-induced Runx2 protein expression was suppressed by pretreatment with U0126. Taken together, these results suggest that Edil3 may stimulate osteoblast differentiation and matrix mineralization by increasing expression of Runx2 through α5β1 integrin /ERK pathway.
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Affiliation(s)
- Sin-Hye Oh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju, Republic of Korea
| | - Jung-Woo Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Yuri Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Mi Nam Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Min-Suk Kook
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Eun Young Choi
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Suhn-Young Im
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju, Republic of Korea
| | - Jeong-Tae Koh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- * E-mail:
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16
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Welch PM, Lee MN, Parra-Vasquez ANG, Welch CF. Jammed Limit of Bijel Structure Formation. Langmuir 2017; 33:13133-13138. [PMID: 29095625 DOI: 10.1021/acs.langmuir.7b02805] [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] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Over the past decade, methods to control microstructure in heterogeneous mixtures by arresting spinodal decomposition via the addition of colloidal particles have led to an entirely new class of bicontinuous materials known as bijels. Herein, we present a new model for the development of these materials that yields to both numerical and analytical evaluation. This model reveals that a single dimensionless parameter that captures both chemical and environmental variables dictates the dynamics and ultimate structure formed in bijels. We demonstrate that this parameter must fall within a fixed range in order for jamming to occur during spinodal decomposition, as well as show that known experimental trends for the characteristic domain sizes and time scales for formation are recovered by this model.
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Affiliation(s)
- P M Welch
- Theoretical Division and Materials Science and Technology Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87544, United States
| | - M N Lee
- Theoretical Division and Materials Science and Technology Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87544, United States
| | - A N G Parra-Vasquez
- Theoretical Division and Materials Science and Technology Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87544, United States
| | - C F Welch
- Theoretical Division and Materials Science and Technology Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87544, United States
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17
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Kim JW, Lee MN, Jeong BC, Oh SH, Kook MS, Koh JT. Chemical inhibitors of c-Met receptor tyrosine kinase stimulate osteoblast differentiation and bone regeneration. Eur J Pharmacol 2017; 806:10-17. [PMID: 28322831 DOI: 10.1016/j.ejphar.2017.03.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 03/13/2017] [Accepted: 03/15/2017] [Indexed: 01/19/2023]
Abstract
The c-Met receptor tyrosine kinase and its ligand, hepatocyte growth factor (HGF), have been recently introduced to negatively regulate bone morphogenetic protein (BMP)-induced osteogenesis. However, the effect of chemical inhibitors of c-Met receptor on osteoblast differentiation process has not been examined, especially the applicability of c-Met chemical inhibitors on in vivo bone regeneration. In this study, we demonstrated that chemical inhibitors of c-Met receptor tyrosine kinase, SYN1143 and SGX523, could potentiate the differentiation of precursor cells to osteoblasts and stimulate regeneration in calvarial bone defects of mice. Treatment with SYN1143 or SGX523 inhibited HGF-induced c-Met phosphorylation in MC3T3-E1 and C3H10T1/2 cells. Cell proliferation of MC3T3-E1 or C3H10T1/2 was not significantly affected by the concentrations of these inhibitors. Co-treatment with chemical inhibitor of c-Met and osteogenic inducing media enhanced osteoblast-specific genes expression and calcium nodule formation accompanied by increased Runx2 expression via c-Met receptor-dependent but Erk-Smad signaling independent pathway. Notably, the administration of these c-Met inhibitors significantly repaired critical-sized calvarial bone defects. Collectively, our results suggest that chemical inhibitors of c-Met receptor tyrosine kinase might be used as novel therapeutics to induce bone regeneration.
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Affiliation(s)
- Jung-Woo Kim
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Mi Nam Lee
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Byung-Chul Jeong
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Pharmacology, Seonam University Medical School, Namwon, Chonbuk 55724, Republic of Korea
| | - Sin-Hye Oh
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Min-Suk Kook
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Oral and Maxillofacial Surgery, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jeong-Tae Koh
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea.
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18
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Park D, Jeong H, Lee MN, Koh A, Kwon O, Yang YR, Noh J, Suh PG, Park H, Ryu SH. Resveratrol induces autophagy by directly inhibiting mTOR through ATP competition. Sci Rep 2016; 6:21772. [PMID: 26902888 PMCID: PMC4763238 DOI: 10.1038/srep21772] [Citation(s) in RCA: 167] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 02/01/2016] [Indexed: 01/03/2023] Open
Abstract
Resveratrol (RSV) is a natural polyphenol that has a beneficial effect on health, and resveratrol-induced autophagy has been suggested to be a key process in mediating many beneficial effects of resveratrol, such as reduction of inflammation and induction of cancer cell death. Although various resveratrol targets have been suggested, the molecule that mediates resveratrol-induced autophagy remains unknown. Here, we demonstrate that resveratrol induces autophagy by directly inhibiting the mTOR-ULK1 pathway. We found that inhibition of mTOR activity and presence of ULK1 are required for autophagy induction by resveratrol. In line with this mTOR dependency, we found that resveratrol suppresses the viability of MCF7 cells but not of SW620 cells, which are mTOR inhibitor sensitive and insensitive cancer cells, respectively. We also found that resveratrol-induced cancer cell suppression occurred ULK1 dependently. For the mechanism of action of resveratrol on mTOR inhibition, we demonstrate that resveratrol directly inhibits mTOR. We found that resveratrol inhibits mTOR by docking onto the ATP-binding pocket of mTOR (i.e., it competes with ATP). We propose mTOR as a novel direct target of resveratrol, and inhibition of mTOR is necessary for autophagy induction.
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Affiliation(s)
- Dohyun Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Heeyoon Jeong
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Mi Nam Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Ara Koh
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Ohman Kwon
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Yong Ryoul Yang
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea
| | - Jungeun Noh
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Pann-Ghill Suh
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea
| | - Hwangseo Park
- Department of Bioscience and Biotechnology, Sejong University, 98 Kunja-Dong, Kwangjin-Ku, Seoul 143-747, Republic of Korea
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.,School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
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19
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Shin H, Lee MN, Choung JS, Kim S, Choi BH, Noh M, Shin JH. Focal Adhesion Assembly Induces Phenotypic Changes and Dedifferentiation in Chondrocytes. J Cell Physiol 2016; 231:1822-31. [PMID: 26661891 DOI: 10.1002/jcp.25290] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 12/10/2015] [Indexed: 01/20/2023]
Abstract
The expansion of autologous chondrocytes in vitro is used to generate sufficient populations for cell-based therapies. However, during monolayer culture, chondrocytes lose inherent characteristics and shift to fibroblast-like cells as passage number increase. Here, we investigated passage-dependent changes in cellular physiology, including cellular morphology, motility, and gene and protein expression, as well as the role of focal adhesion and cytoskeletal regulation in the dedifferentiation process. We found that the gene and protein expression levels of both the focal adhesion complex and small Rho GTPases are upregulated with increasing passage number and are closely linked to chondrocyte dedifferentiation. The inhibition of focal adhesion kinase (FAK) but not small Rho GTPases induced the loss of fibroblastic traits and the recovery of collagen type II, aggrecan, and SOX9 expression levels in dedifferentiated chondrocytes. Based on these findings, we propose a strategy to suppress chondrogenic dedifferentiation by inhibiting the identified FAK or Src pathways while maintaining the expansion capability of chondrocytes in a 2D environment. These results highlight a potential therapeutic target for the treatment of skeletal diseases and the generation of cartilage in tissue-engineering approaches. J. Cell. Physiol. 231: 1822-1831, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Hyunjun Shin
- Division of Mechanical Engineering, School of Mechanical, Aerospace, and Systems Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Republic of Korea
| | - Mi Nam Lee
- Division of Mechanical Engineering, School of Mechanical, Aerospace, and Systems Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Republic of Korea
| | - Jin Seung Choung
- Division of Mechanical Engineering, School of Mechanical, Aerospace, and Systems Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Republic of Korea
| | - Sanghee Kim
- Department of Mechanical Systems Engineering, Hansung University, Seoul, Republic of Korea
| | - Byung Hyune Choi
- Department of Biomedical Sciences, Inha University College of Medicine, Jung-gu, Incheon, Republic of Korea
| | - Minsoo Noh
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Gwanak-gu, Seoul, Republic of Korea
| | - Jennifer H Shin
- Division of Mechanical Engineering, School of Mechanical, Aerospace, and Systems Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Republic of Korea
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20
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Gweon B, Kim M, Kim K, Choung J, Lee MN, Ko UH, Hyun JW, Choe W, Shin JH. Role of atmospheric pressure plasma (APP) in wound healing: APP-induced antifibrotic process in human dermal fibroblasts. Exp Dermatol 2015; 25:159-61. [PMID: 26439885 DOI: 10.1111/exd.12865] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/30/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Bomi Gweon
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea
| | - Mina Kim
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea
| | - Kijung Kim
- Department of Physics, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea
| | - Jinseung Choung
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea
| | - Mi Nam Lee
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea
| | - Ung Hyun Ko
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea
| | - Jin Won Hyun
- School of Medicine, Jeju National University, Jeju-si, Jeju Special Self-Governing Province, Korea
| | - Wonho Choe
- Department of Physics, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea
| | - Jennifer H Shin
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea.,Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon, Korea
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21
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Koh A, Park D, Jeong H, Lee J, Lee MN, Suh PG, Ryu SH. Regulation of C1-Ten protein tyrosine phosphatase by p62/SQSTM1-mediated sequestration and degradation. Cell Signal 2014; 26:2470-80. [PMID: 25101860 DOI: 10.1016/j.cellsig.2014.07.033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 07/08/2014] [Accepted: 07/28/2014] [Indexed: 12/21/2022]
Abstract
C1-Ten is a member of the tensin family of focal adhesion molecules but recent studies suggest it plays a more active role in many biological processes because of its potential association with diabetes and cancers. However, relatively little is known about the regulation of C1-Ten, such as changes in its protein level or cellular localization. The cellular localization of C1-Ten is unique because it is expressed in cytoplasmic puncta but nothing is known about these puncta. Here, we show that p62 sequestrates C1-Ten into puncta, making C1-Ten diffuse into the cytoplasm upon p62 depletion. More importantly, p62-mediated C1-Ten sequestration promoted C1-Ten ubiquitination and proteasomal degradation. p62-mediated protein reduction was specific to C1-Ten, and not other tensins such as tensin1 and tensin3. Thus, our results link cellular localization of C1-Ten to an off-switch site for C1-Ten. Additionally, p62 expression increased but C1-Ten protein decreased during muscle differentiation, supporting a role for p62 as a physiological regulator of C1-Ten.
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Affiliation(s)
- Ara Koh
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, South Korea
| | - Dohyun Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, South Korea
| | - Heeyoon Jeong
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, South Korea
| | - Jiyoun Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, South Korea
| | - Mi Nam Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, South Korea
| | - Pann-Ghill Suh
- School of Nano-Biotechnology and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 689-798, South Korea
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, South Korea.
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22
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Park D, Lee MN, Jeong H, Koh A, Yang YR, Suh PG, Ryu SH. Parkin ubiquitinates mTOR to regulate mTORC1 activity under mitochondrial stress. Cell Signal 2014; 26:2122-30. [PMID: 25007995 DOI: 10.1016/j.cellsig.2014.06.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [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: 04/21/2014] [Revised: 06/23/2014] [Accepted: 06/27/2014] [Indexed: 01/15/2023]
Abstract
mTORC1, a kinase complex that is considered a master regulator of cellular growth and proliferation, is regulated by many extra- and intracellular signals. Among these signals, mitochondrial status is known to have an impact on the effects of mTORC1 on cell growth and survival. However, how mitochondrial status affects mTORC1 activity, notably the molecular link, is not fully elucidated. Here, we found that Parkin can interact with and ubiquitinate mTOR. We also identified K2066 and K2306 as Parkin-dependent and mitochondrial stress-induced mTOR ubiquitination residues. This ubiquitination by Parkin is required for maintenance of mTORC1 activity under mitochondrial stress. With regard to the physiological meaning of mTORC1 activity under mitochondrial stress, we suggest that mTORC1 plays a pro-survival role.
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Affiliation(s)
- Dohyun Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Mi Nam Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Heeyoon Jeong
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Ara Koh
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Yong Ryoul Yang
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea
| | - Pann-Ghill Suh
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
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23
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Lee MN, Choi KH, Kim DK, Kim SH. Mosaic double aneuploidy (45,X/47,XX,+8) with aortic dissection. Genet Couns 2014; 25:177-182. [PMID: 25059016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Chromosomal aneuploidy is considerably frequent and may involve either autosomes or sex chromosomes. While double aneuploidy involving both autosomal and sex chromosomes is rare, several reports described the cases of sex chromosomal aneuploidies in combination with trisomy 21, such as Down-Klinefelter and Down-Turner syndrome. However, trisomy 8-Turner syndrome has been rarely described to date. Here we report a case of a 28-year-old female with mosaic trisomy 8-Turner syndrome. The patient was referred to our hospital for aortic dissection. On physical evaluation, features of her phenotype, which included short stature, webbed neck and cubitus valgus, suggested congenital anomalies such as Turner syndrome. Chest CT revealed aortic dissection with bicuspid aortic valve and coarctation. G-banding cytogenetic analysis of peripheral blood showed mosaicism with two cell lines (45,X[17]/47,XX,+8[33]). FISH analysis indicated that 15% of the cells were of monosomy X karyotype and 85% of the cells were with XX karyotype and trisomy 8 was detected only in XX cells. Though the patient exhibited clinical features of Turner syndrome, somatic stigmas present were not clearly distinguishable from those of trisomy 8, such as short stature, skeletal and cardiac abnormalities. Observations from most of the double aneuploidy cases indicated that the patient's phenotype was not necessarily in correlation to the ratio of autosomal and sex chromosomal aberrations. Mosaicism in trisomy 8-Turner syndrome was rarely documented and we believe this is the first reported case of mosaicism in trisomy 8-Turner syndrome presenting with aortic dissection and surviving into adulthood.
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24
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Kim ES, Jang DS, Yang SY, Lee MN, Jin KS, Cha HJ, Kim JK, Sung YC, Choi KY. Controlled release of human growth hormone fused with a human hybrid Fc fragment through a nanoporous polymer membrane. Nanoscale 2013; 5:4262-4269. [PMID: 23546513 DOI: 10.1039/c3nr00474k] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Nanotechnology has been applied to the development of more effective and compatible drug delivery systems for therapeutic proteins. Human growth hormone (hGH) was fused with a hybrid Fc fragment containing partial Fc domains of human IgD and IgG4 to produce a long-acting fusion protein. The fusion protein, hGH-hyFc, resulted in the increase of the hydrodynamic diameter (ca. 11 nm) compared with the diameter (ca. 5 nm) of the recombinant hGH. A diblock copolymer membrane with nanopores (average diameter of 14.3 nm) exhibited a constant release rate of hGH-hyFc. The hGH-hyFc protein released in a controlled manner for one month was found to trigger the phosphorylation of Janus kinase 2 (JAK2) in human B lymphocyte and to exhibit an almost identical circular dichroism spectrum to that of the original hGH-hyFc, suggesting that the released fusion protein should maintain the functional and structural integrity of hGH. Thus, the nanoporous release device could be a potential delivery system for the long-term controlled release of therapeutic proteins fused with the hybrid Fc fragment.
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Affiliation(s)
- Eung-Sam Kim
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, Korea
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25
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Lee MN, Koh A, Park D, Jang JH, Kwak D, Jeon H, Kim J, Choi EJ, Jeong H, Suh PG, Ryu SH. Deacetylated αβ-tubulin acts as a positive regulator of Rheb GTPase through increasing its GTP-loading. Cell Signal 2012. [PMID: 23178303 DOI: 10.1016/j.cellsig.2012.11.006] [Citation(s) in RCA: 6] [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] [Indexed: 12/23/2022]
Abstract
Ras homolog enriched in brain (Rheb) regulates diverse cellular functions by modulating its nucleotide-bound status. Although Rheb contains a high basal GTP level, the regulatory mechanism of Rheb is not well understood. In this study, we propose soluble αβ-tubulin acts as a constitutively active Rheb activator, which may explain the reason why Rheb has a high basal GTP levels. We found that soluble αβ-tubulin is a direct Rheb-binding protein and that its deacetylated form has a high binding affinity for Rheb. Modulation of both soluble and acetylated αβ-tubulin levels affects the level of GTP-bound Rheb. This occurs in the mitotic phase in which the level of acetylated αβ-tubulin is increased but that of GTP-bound Rheb is decreased. Constitutively active Rheb-overexpressing cells showed an abnormal mitotic progression, suggesting the deacetylated αβ-tubulin-mediated regulation of Rheb status may be important for proper mitotic progression. Taken together, we propose that deacetylated soluble αβ-tubulin is a novel type of positive regulator of Rheb and may play a role as a temporal regulator for Rheb during the cell cycle.
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Affiliation(s)
- Mi Nam Lee
- Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea
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26
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Yang YR, Song M, Lee H, Jeon Y, Choi EJ, Jang HJ, Moon HY, Byun HY, Kim EK, Kim DH, Lee MN, Koh A, Ghim J, Choi JH, Lee-Kwon W, Kim KT, Ryu SH, Suh PG. O-GlcNAcase is essential for embryonic development and maintenance of genomic stability. Aging Cell 2012; 11:439-48. [PMID: 22314054 DOI: 10.1111/j.1474-9726.2012.00801.x] [Citation(s) in RCA: 178] [Impact Index Per Article: 14.8] [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: 12/16/2022] Open
Abstract
Dysregulation of O-GlcNAc modification catalyzed by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) contributes to the etiology of chronic diseases of aging, including cancer, cardiovascular disease, type 2 diabetes, and Alzheimer's disease. Here we found that natural aging in wild-type mice was marked by a decrease in OGA and OGT protein levels and an increase in O-GlcNAcylation in various tissues. Genetic disruption of OGA resulted in constitutively elevated O-GlcNAcylation in embryos and led to neonatal lethality with developmental delay. Importantly, we observed that serum-stimulated cell cycle entry induced increased O-GlcNAcylation and decreased its level after release from G2/M arrest, indicating that O-GlcNAc cycling by OGT and OGA is required for precise cell cycle control. Constitutively, elevated O-GlcNAcylation by OGA disruption impaired cell proliferation and resulted in mitotic defects with downregulation of mitotic regulators. OGA loss led to mitotic defects including cytokinesis failure and binucleation, increased lagging chromosomes, and micronuclei formation. These findings suggest an important role for O-GlcNAc cycling by OGA in embryonic development and the regulation of the maintenance of genomic stability linked to the aging process.
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Affiliation(s)
- Yong Ryoul Yang
- Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang, Kyungbuk 790-784, Republic of Korea
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27
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Kwak D, Choi S, Jeong H, Jang JH, Lee Y, Jeon H, Lee MN, Noh J, Cho K, Yoo JS, Hwang D, Suh PG, Ryu SH. Osmotic stress regulates mammalian target of rapamycin (mTOR) complex 1 via c-Jun N-terminal Kinase (JNK)-mediated Raptor protein phosphorylation. J Biol Chem 2012; 287:18398-407. [PMID: 22493283 DOI: 10.1074/jbc.m111.326538] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
mTOR complex 1 (mTORC1) is a multiprotein complex that integrates diverse signals including growth factors, nutrients, and stress to control cell growth. Raptor is an essential component of mTORC1 that functions to recruit specific substrates. Recently, Raptor was suggested to be a key target of regulation of mTORC1. Here, we show that Raptor is phosphorylated by JNK upon osmotic stress. We identified that osmotic stress induces the phosphorylation of Raptor at Ser-696, Thr-706, and Ser-863 using liquid chromatography-tandem mass spectrometry. We found that JNK is responsible for the phosphorylation. The inhibition of JNK abolishes the phosphorylation of Raptor induced by osmotic stress in cells. Furthermore, JNK physically associates with Raptor and phosphorylates Raptor in vitro, implying that JNK is responsible for the phosphorylation of Raptor. Finally, we found that osmotic stress activates mTORC1 kinase activity in a JNK-dependent manner. Our findings suggest that the molecular link between JNK and Raptor is a potential mechanism by which stress regulates the mTORC1 signaling pathway.
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Affiliation(s)
- Dongoh Kwak
- Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Kyungbuk, Korea
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28
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Lee MN, Koh A, Park D, Jang J, Kwak D, Jeon H, Kim J, Jung H, Suh PG, Ryu SH. Deacetylated αβ‐tubulin dimer acts as a positive regulator for Rheb GTPase. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.591.3] [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: 11/11/2022]
Affiliation(s)
| | - Ara Koh
- POSTECHPohangKorea, Republic of
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Cho K, Lee HJ, Lee SY, Woo H, Lee MN, Seok JH, Lee CJ. Oleanolic acid and ursolic acid derived from Cornus officinalis Sieb. et Zucc. suppress epidermal growth factor- and phorbol ester-induced MUC5AC mucin production and gene expression from human airway epithelial cells. Phytother Res 2011; 25:760-4. [PMID: 21442679 DOI: 10.1002/ptr.3488] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 04/13/2010] [Accepted: 03/04/2011] [Indexed: 12/16/2023]
Abstract
In this study, the effects of oleanolic acid and ursolic acid on MUC5AC mucin production and gene expression induced by epidermal growth factor (EGF) and phorbol 12-myristate 13-acetate (PMA) from human airway epithelial cells were investigated. Confluent NCI-H292 cells were pretreated with each agent for 30 min and then stimulated with EGF and PMA for 24 h, respectively. MUC5AC mucin gene expression and mucin protein production were measured by RT-PCR and ELISA. Oleanolic acid and ursolic acid were found to inhibit the production of MUC5AC mucin protein induced by EGF and PMA, and both compounds also inhibited the expression of MUC5AC mucin gene induced by EGF and PMA. These results suggest that oleanolic acid and ursolic acid can regulate mucin gene expression, and production of mucin protein, by directly acting on airway epithelial cells.
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Affiliation(s)
- Kyoungrai Cho
- Department of Otorhinolaryngology, Sanggye Paik Hospital, College of Medicine, Inje University, Seoul, Korea
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30
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Jeon H, Kwak D, Noh J, Lee MN, Lee CS, Suh PG, Ryu SH. Phospholipase D2 induces stress fiber formation through mediating nucleotide exchange for RhoA. Cell Signal 2011; 23:1320-6. [PMID: 21440060 DOI: 10.1016/j.cellsig.2011.03.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 03/15/2011] [Indexed: 12/23/2022]
Abstract
Phospholipase D (PLD) is involved in diverse cellular processes including cell movement, adhesion, and vesicle trafficking through cytoskeletal rearrangements. However, the mechanism by which PLD induces cytoskeletal reorganization is still not fully understood. Here, we describe a new link to cytoskeletal changes that is mediated by PLD2 through direct nucleotide exchange on RhoA. We found that PLD2 induces RhoA activation independent of its lipase activity. PLD2 directly interacted with RhoA, and the PX domain of PLD2 specifically recognized nucleotide-free RhoA. Finally, we found that the PX domain of PLD2 has guanine nucleotide-exchange factor (GEF) activity for RhoA in vitro. In addition, we verified that overexpression of the PLD2-PX domain induces RhoA activation, thereby provoking stress fiber formation. Together, our findings suggest that PLD2 functions as an upstream regulator of RhoA, which enables us to understand how PLD2 regulates cytoskeletal reorganization in a lipase activity-independent manner.
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Affiliation(s)
- Hyeona Jeon
- Division of Molecular and Life Sciences, Pohang University of Science and Technology, Pohang, 790-784, South Korea
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31
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Lee HJ, Lee SY, Lee MN, Kim JH, Chang GT, Seok JH, Lee CJ. Inhibition of secretion, production and gene expression of mucin from cultured airway epithelial cells by prunetin. Phytother Res 2011; 25:1196-200. [PMID: 21305630 DOI: 10.1002/ptr.3362] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 10/20/2010] [Accepted: 10/25/2010] [Indexed: 11/09/2022]
Abstract
This study investigated whether prunetin significantly affects the secretion, production and gene expression of mucin from cultured airway epithelial cells. Confluent primary rat tracheal surface epithelial (RTSE) cells were pretreated with adenosine triphosphate (ATP) for 5 min and then chased for 30 min in the presence of prunetin to assess the effect on mucin secretion using enzyme-linked immunosorbent assay (ELISA). At the same time, confluent NCI-H292 cells were pretreated with prunetin for 30 min and then stimulated with epidermal growth factor (EGF) or phorbol 12-myristate 13-acetate (PMA) for 24 h, respectively. The MUC5AC mucin gene expression and mucin protein production were measured by reverse transcription-polymerase chain reaction (RT-PCR) and ELISA. The results were as follows: (1) prunetin significantly suppressed ATP-induced mucin secretion from cultured RTSE cells; (2) prunetin inhibited the production of MUC5AC mucin protein induced by EGF or PMA from NCI-H292 cells; (3) prunetin also inhibited the expression of MUC5AC mucin gene induced by EGF or PMA from NCI-H292 cells. This result suggests that prunetin can regulate the secretion, production and gene expression of mucin, by directly acting on airway epithelial cells.
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Affiliation(s)
- Hyun Jae Lee
- Department of Pharmacology, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
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32
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Kim IH, Lee MN, Ryu SH, Park JW. Nanoscale Mapping and Affinity Constant Measurement of Signal-Transducing Proteins by Atomic Force Microscopy. Anal Chem 2011; 83:1500-3. [DOI: 10.1021/ac102695e] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Il Hong Kim
- Department of Chemistry, ‡Department of Life Science, §Division of Integrative Biosciences and Biotechnology, National Core Research Center for Systems Bio-Dynamics, ⊥Postech Biotech Center, Pohang University of Science and Technology, San 31 Hyoja-dong, Pohang, 790-784, Korea
| | - Mi Nam Lee
- Department of Chemistry, ‡Department of Life Science, §Division of Integrative Biosciences and Biotechnology, National Core Research Center for Systems Bio-Dynamics, ⊥Postech Biotech Center, Pohang University of Science and Technology, San 31 Hyoja-dong, Pohang, 790-784, Korea
| | - Sung Ho Ryu
- Department of Chemistry, ‡Department of Life Science, §Division of Integrative Biosciences and Biotechnology, National Core Research Center for Systems Bio-Dynamics, ⊥Postech Biotech Center, Pohang University of Science and Technology, San 31 Hyoja-dong, Pohang, 790-784, Korea
| | - Joon Won Park
- Department of Chemistry, ‡Department of Life Science, §Division of Integrative Biosciences and Biotechnology, National Core Research Center for Systems Bio-Dynamics, ⊥Postech Biotech Center, Pohang University of Science and Technology, San 31 Hyoja-dong, Pohang, 790-784, Korea
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Lee HJ, Lee SY, Lee MN, Kim JH, Chang GT, Seok JH, Lee CJ. Daidzein regulates secretion, production and gene expression of mucin from airway epithelial cells stimulated by proinflammatory factor and growth factor. Pulm Pharmacol Ther 2010; 24:128-32. [PMID: 20708703 DOI: 10.1016/j.pupt.2010.08.003] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Revised: 06/28/2010] [Accepted: 08/05/2010] [Indexed: 11/27/2022]
Abstract
In this study, we investigated whether daidzein significantly affects secretion, production and gene expression of mucin from cultured airway epithelial cells. Confluent primary rat tracheal surface epithelial (RTSE) cells were pretreated with adenosine triphosphate (ATP) for 5 min and then chased for 30 min in the presence of daidzein to assess the effect on mucin secretion using ELISA. At the same time, confluent NCI-H292 cells were pretreated with daidzein for 30 min and then stimulated with EGF and PMA for 24 h, respectively. The MUC5AC mucin gene expression and mucin protein production were measured by RT-PCR and ELISA. The results were as follows: (1) daidzein significantly decreased ATP-induced mucin secretion from cultured RTSE cells; (2) daidzein inhibited the production of MUC5AC mucin protein induced by EGF or PMA from NCI-H292 cells; (3) daidzein also inhibited the expression of MUC5AC mucin gene induced by EGF or PMA from NCI-H292 cells. This result suggests that daidzein can regulate secretion, production and gene expression of mucin, by directly acting on airway epithelial cells.
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Affiliation(s)
- Hyun Jae Lee
- Department of Pharmacology, College of Medicine, Chungnam National University, 6 Munhwa-Dong, Joong-Gu, Daejeon 301131, Republic of Korea
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Lee CJ, Lee MN, Lee HJ, Lee SY, Seok JH, Jordan MA, Wilson L. Abstract 772: Effects of natural products on proliferation of human breast cancer cells induced by estrogen or PhIP, a heterocyclic amine compound derived from cooked meat. Cancer Res 2010. [DOI: 10.1158/1538-7445.am10-772] [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: 11/16/2022]
Abstract
Abstract
According to the traditional Asian medicine, herbs containing daidzein, hesperidin, oleanolic acid and bacalein were used as anti-inflammatory and anti-tumor folk medicines. On the basis of this information, in this study, we investigated whether natural products including daidzein, hesperidin, oleanolic acid and bacalein affect proliferation of MCF-7 human breast cancer cells stimulated by 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) or estradiol. The results were as follows : (1) Both estradiol and PhIP significantly induced proliferation of MCF-7 cells at the concentrations of 10nM and 100nM, respectively; (2) Oleanolic acid and baicalein inhibited proliferation of PhIP-induced proliferation of MCF-7 cells, dose-dependently; (3) Daidzein and hesperidin also inhibited proliferation of estradiol-induced proliferation of MCF-7 cells, dose-dependently. We suggest that these four natural compounds can be novel drug candidates for preventing breast cancer provoked by dietary estrogenic compounds found in cooked meat such as PhIP. Also, effects of these four natural compounds on MAPK-ERK pathway should be investigated for elucidation of action mechanism through future study.
(Key words: Natural products, MCF-7, PhIP, Estradiol)
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 772.
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Affiliation(s)
- Choong Jae Lee
- 1Chungnam National University School of Medicine, Daejeon, Korea, Republic of
| | - Mi Nam Lee
- 1Chungnam National University School of Medicine, Daejeon, Korea, Republic of
| | - Hyun Jae Lee
- 1Chungnam National University School of Medicine, Daejeon, Korea, Republic of
| | - Su Yel Lee
- 1Chungnam National University School of Medicine, Daejeon, Korea, Republic of
| | - Jeong Ho Seok
- 1Chungnam National University School of Medicine, Daejeon, Korea, Republic of
| | - Mary Ann Jordan
- 2Department of Molecular, Cellular & Developmental Biology, University of California, Santa Barbara, CA
| | - Leslie Wilson
- 2Department of Molecular, Cellular & Developmental Biology, University of California, Santa Barbara, CA
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Lee HJ, Lee SY, Jeon BK, Lee JW, Lee MN, Kim JO, Lee CJ. Regulation of Tumor Necrosis Factor-α-induced Airway Mucin Production and Gene Expression by Carbenoxolone, Prunetin, and Silibinin. Tuberc Respir Dis (Seoul) 2010. [DOI: 10.4046/trd.2010.69.5.348] [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: 11/24/2022] Open
Affiliation(s)
- Hyun Jae Lee
- Department of Pharmacology, Chungnam National University School of Medicine, Daejeon, Korea
| | - Su Yel Lee
- Department of Pharmacology, Chungnam National University School of Medicine, Daejeon, Korea
| | - Byeong Kyou Jeon
- Department of Radiologic Technology, Daegu Health College, Daegu, Korea
| | | | - Mi Nam Lee
- Department of Pharmacology, Chungnam National University School of Medicine, Daejeon, Korea
| | - Ju-Ock Kim
- Pulmonology Section, Department of Internal Medicine, Chungnam National University Hospital, Chungnam National University School of Medicine, Daejeon, Korea
| | - Choong Jae Lee
- Department of Pharmacology, Chungnam National University School of Medicine, Daejeon, Korea
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Heo HJ, Lee SY, Lee MN, Lee HJ, Seok JH, Lee CJ. Genistein and curcumin suppress epidermal growth factor-induced MUC5AC mucin production and gene expression from human airway epithelial cells. Phytother Res 2009; 23:1458-61. [DOI: 10.1002/ptr.2801] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lee SH, Song R, Lee MN, Kim CS, Lee H, Kong YY, Kim H, Jang SK. A molecular chaperone glucose-regulated protein 94 blocks apoptosis induced by virus infection. Hepatology 2008; 47:854-66. [PMID: 18273841 DOI: 10.1002/hep.22107] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
UNLABELLED The hepatitis C virus (HCV) E2 protein has been shown to block apoptosis and has been suggested to facilitate persistent infection of the virus. Here, we report that the anti-apoptotic activity of E2 is mediated by activation of nuclear factor kappa B (NF-kappaB) that directs expression of survival gene products such as tumor necrosis factor (TNF-alpha) receptor-associated factor 2 (TRAF2), X-chromosome-linked inhibitor of apoptosis protein (XIAP), FLICE-like inhibitory protein (FLIP), and survivin. Increased levels of these proteins were observed in HCV-infected cells and a cell line producing HCV E2 protein. The activation of NF-kappaB was mediated by HCV-E2-induced expression of the molecular chaperone glucose-regulated protein 94 (GRP94). Overexpression of GRP94 alone resulted in expression of anti-apoptotic proteins and blocked apoptosis induced by tumor-necrosis-related apoptosis-inducing ligand (TRAIL). Interestingly, increased levels of GRP94 were observed in cells supporting HCV proliferation that originated from liver tissues from HCV patients. Moreover, small interfering RNA (siRNA) knock-down of GRP94 nullified the anti-apoptotic activity of HCV E2. CONCLUSION These data indicate that HCV E2 blocks apoptosis induced by HCV infection and the host immune system through overproduction of GRP94, and that HCV E2 plays an important role in persistent HCV infection.
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Affiliation(s)
- Song Hee Lee
- PBC, Department of Life Science, Pohang University of Science and Technology, Hyoja-dong, Pohang, Kyungbuk, Korea
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Song JH, Jeon H, Lee MN, Kwak DO, Yea K, Suh P, Ryu SH. Function of Rnd in Insulin signaling pathway. FASEB J 2007. [DOI: 10.1096/fasebj.21.5.a617] [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: 11/11/2022]
Affiliation(s)
- Jin Hwa Song
- Life Science DepartmentPOSTECHSan31, Hyoja‐Dong, Nam‐GuPohangRepublic of Korea
| | - Hyeona Jeon
- Life Science DepartmentPOSTECHSan31, Hyoja‐Dong, Nam‐GuPohangRepublic of Korea
| | - Mi Nam Lee
- Life Science DepartmentPOSTECHSan31, Hyoja‐Dong, Nam‐GuPohangRepublic of Korea
| | - Dong Oh Kwak
- Life Science DepartmentPOSTECHSan31, Hyoja‐Dong, Nam‐GuPohangRepublic of Korea
| | - KyungMoo Yea
- Life Science DepartmentPOSTECHSan31, Hyoja‐Dong, Nam‐GuPohangRepublic of Korea
| | - Pann‐Ghill Suh
- Life Science DepartmentPOSTECHSan31, Hyoja‐Dong, Nam‐GuPohangRepublic of Korea
| | - Sung Ho Ryu
- Life Science DepartmentPOSTECHSan31, Hyoja‐Dong, Nam‐GuPohangRepublic of Korea
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Ha SH, Kim DH, Kim IS, Kim JH, Lee MN, Lee HJ, Kim JH, Jang SK, Suh PG, Ryu SH. PLD2 forms a functional complex with mTOR/raptor to transduce mitogenic signals. Cell Signal 2006; 18:2283-91. [PMID: 16837165 DOI: 10.1016/j.cellsig.2006.05.021] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [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: 04/26/2006] [Revised: 05/11/2006] [Accepted: 05/11/2006] [Indexed: 10/24/2022]
Abstract
Mammalian target-of-rapamycin (mTOR), which is a master controller of cell growth, senses a mitogenic signal in part through the lipid second messenger phosphatidic acid (PA), generated by phospholipase D (PLD). To understand further which isozymes of PLD are involved in this process, we compared the effect of PLD isozymes on mTOR activation. We found that PLD2 has an essential role in mitogen-induced mTOR activation as the siRNA-mediated knockdown of PLD2, not of PLD1, profoundly reduced the phosphorylations of S6K1 and 4EBP1, well-known mTOR effectors. Furthermore, exogenous PA-induced mTOR activation was abrogated by PLD2 knockdown, but not by PLD1 knockdown. This abrogation was found to be the result of complex formation between PLD2 and mTOR/raptor. PLD2 possesses a TOS-like motif (Phe-Glu-Val-Gln-Val, a.a. 265-269), through which it interacts with raptor independently of the other TOS motif-containing proteins, S6K1 and 4EBP1. PLD2-dependent mTOR activation appears to require PLD2 binding to mTOR/raptor with lipase activity, since lipase-inactive PLD2 cannot trigger mTOR activation despite its ability to interact with mTOR/raptor. Abrogation of mitogen-dependent mTOR activation by PLD2 knockdown was rescued only by wild type PLD2, but not by raptor binding-deficient and lipase-inactive PLD2. Our results demonstrate the importance of localized PA generation for the mitogen-induced activation of mTOR, which is achieved by a specific interaction between PLD2 and mTOR/raptor.
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Affiliation(s)
- Sang Hoon Ha
- Division of Molecular and Life Sciences, Pohang University of Science and Technology, Pohang, Kyungbook 790-784, Republic of Korea
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Lee MN, Jung EY, Kwun HJ, Jun HK, Yu DY, Choi YH, Jang KL. Hepatitis C virus core protein represses the p21 promoter through inhibition of a TGF-beta pathway. J Gen Virol 2002; 83:2145-2151. [PMID: 12185267 DOI: 10.1099/0022-1317-83-9-2145] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [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: 01/29/2023] Open
Abstract
The increased proliferation rate of hepatocytes is one of the major risk factors for the development of hepatocellular carcinoma. In this study, we investigated the mechanism by which hepatitis C virus (HCV) core protein represses transcription of the universal cyclin-dependent kinase inhibitor p21 gene in murine fibroblast NIH 3T3 cells. From the transient reporter assays of p21 promoter, we found that the TGF-beta-responsive element (TbetaRE) located between -83 and -74 of the p21 promoter is responsible for the effect. The TGF-beta-induced p21 promoter activity was specifically decreased by HCV core protein and in the presence of the inhibitory Smad7 the repression effect was almost completely abolished. Furthermore, HCV core protein stimulated the growth rate of NIH 3T3 cells and could overcome growth arrest by TGF-beta but not by butyrate, suggesting that HCV core protein stimulates cell cycle progression by repressing p21 transcription through a TGF-beta pathway.
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Affiliation(s)
- Mi Nam Lee
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Korea1
| | - Eun Young Jung
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Korea1
| | - Hyun Jin Kwun
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Korea1
| | - Hong Ki Jun
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Korea1
| | - Dae-Yeul Yu
- Korea Research Institute of Bioscience and Biotechnology, Taejon 305-333, Korea2
| | - Yung Hyun Choi
- Department of Biochemistry, College of Oriental Medicine, Dong-Eui University, Pusan 614-052, Korea3
| | - Kyung Lib Jang
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Korea1
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Jung EY, Lee MN, Yang HY, Yu D, Jang KL. The repressive activity of hepatitis C virus core protein on the transcription of p21(waf1) is regulated by protein kinase A-mediated phosphorylation. Virus Res 2001; 79:109-15. [PMID: 11551651 DOI: 10.1016/s0168-1702(01)00335-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [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: 02/02/2023]
Abstract
Hepatitis C virus (HCV) core protein is known to repress the transcription of p21(waf1) directly in a p53-independent manner. In this study, the region of HCV core protein responsible for the transcriptional repression of p21 promoter was determined. N-terminal half of core protein almost completely lost the ability to repress p21 promoter, indicating that the domain required for the majority of p21 repression is located between amino acid positions 84 and 191. The trans-repression activity of HCV core mutant S99L on p21 gene expression was similar to that of wild type core protein whereas mutation of the 116th amino acid Ser into either Ile or Ala completely abolished the repressive ability of HCV core protein. In addition, the trans-repression activity of HCV core mutant S116D was similar to that of wild type core protein, suggesting that an acidic aspartate residue can mimic the effect of phosphorylation. When treated with a protein kinase A (PKA) inhibitor, H-89, the inhibitory activity of wild-type HCV core protein was dose-dependently decreased and was completely lost at the concentration of 5 microM. On the contrary, the repression activity of HCV core protein was increased by treatment with a PKA activator, dibutyryl-cAMP, indicating that the p21 repressive activity of HCV core protein is regulated by phosphorylation at S-116 by protein PKA
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Affiliation(s)
- E Y Jung
- Department of Microbiology, College of Natural Sciences, Pusan National University, 609-735, Pusan, South Korea
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Abstract
Using in vitro import assays into purified mitochondria and chloroplasts we found that Arabidopsis ferrochelatase-I and ferrochelatase-II were not imported into mitochondria purified from Arabidopsis (or several other plants) but were imported into pea leaf chloroplasts. Other dual targeted proteins could be imported into purified mitochondria from Arabidopsis. As only two ferrochelatase genes are present in the completed Arabidopsis genome, the presence of ferrochelatase activity in plant mitochondria needs to be re-evaluated. Previous reports of Arabidopsis ferrochelatase-I import into pea mitochondria are due to the fact that pea leaf (and root) mitochondria appear to import a variety, but not all chloroplast proteins. Thus pea mitochondria are not a suitable system to either study dual targeting, or to distinguish between isozymes present in mitochondria and chloroplasts.
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Affiliation(s)
- R Lister
- Department of Biochemistry, University of Western Australia, Crawley, Australia
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Abstract
Hepatitis C virus (HCV) NS3 protein is known to affect normal cellular functions, such as cell proliferation and cell death, and to be involved, either directly or indirectly, in HCV hepatocarcinogenesis. In this study, we demonstrated that NS3 protein could specifically repress the promoter activity of p21 in a dose-dependent manner. The effect was not cell type-specific and was synergistic when combined with HCV core protein. Repression of the p21 promoter by NS3 was almost completely lost when p53 binding sites present on the p21 promoter were removed. Furthermore, p53 binding sites were sufficient to confer a strong NS3 responsiveness to an heterologous promoter, suggesting that NS3 represses the transcription of p21 by modulating the activity of p53. Although the NS3 protein domain required for the majority of p21 repression was located on the protease domain, the proteinase activity itself does not seem to be necessary for repression. Both transcription and protein stability of p53 were unaffected by NS3, suggesting that NS3 might repress transcription of p21 by inhibiting the regulatory activity of p53 via protein-protein interaction(s). Finally, the growth rate of NS3-expressing cell lines was at least twice as fast as that of the parent NIH 3T3 cells, indicating that the repression of p21 is actually reflected by the stimulation of cell growth.
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Affiliation(s)
- Hyun Jin Kwun
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Republic of Korea1
| | - Eun Young Jung
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Republic of Korea1
| | - Ji Young Ahn
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Republic of Korea1
| | - Mi Nam Lee
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Republic of Korea1
| | - Kyung Lib Jang
- Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, Republic of Korea1
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Lee MN. Compliance: offense is the best defense. J AHIMA 1999; 70:22-3. [PMID: 10977401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Affiliation(s)
- M N Lee
- Saint Anthony's Health Center, Alton, IL, USA
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45
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Kim BC, Lee MN, Kim JY, Lee SS, Chang JD, Kim SS, Lee SY, Kim JH. Roles of phosphatidylinositol 3-kinase and Rac in the nuclear signaling by tumor necrosis factor-alpha in rat-2 fibroblasts. J Biol Chem 1999; 274:24372-7. [PMID: 10446216 DOI: 10.1074/jbc.274.34.24372] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [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: 11/06/2022] Open
Abstract
We investigated the extent to which phosphatidylinositol 3-kinase (PI 3-kinase) and Rac, a member of the Rho family of small GTPases, are involved in the signaling cascade triggered by tumor necrosis factor (TNF)-alpha leading to activation of c-fos serum response element (SRE) and c-Jun amino-terminal kinase (JNK) in Rat-2 fibroblasts. Inhibition of PI 3-kinase by LY294002 or wortmannin, two specific PI 3-kinase antagonists, or co-transfection with a dominant negative mutant of PI 3-kinase dose-dependently blocked stimulation of c-fos SRE by TNF-alpha. Similarly, LY294002 significantly diminished TNF-alpha-induced activation of JNK, suggesting that nuclear signaling triggered by TNF-alpha is dependent on PI 3-kinase-mediated activation of both c-fos SRE and JNK. We also found nuclear signaling by TNF-alpha to be Rac-dependent, as demonstrated by the inhibitory effect of transient co-transfection with a dominant negative Rac mutant, RacN17. Our findings suggest that Rac is situated downstream of PI 3-kinase in the TNF-alpha signaling pathway to the nucleus, and we conclude that PI 3-kinase and Rac each plays a pivotal role in the nuclear signaling cascade triggered by TNF-alpha.
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Affiliation(s)
- B C Kim
- Department of Life Science, Kwang-Ju Institute of Science and Technology, Kwang-Ju 500-712, Korea
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Sathananthan AH, Ng SC, Trounson AO, Bongso A, Ratnam SS, Ho J, Mok H, Lee MN. The effects of ultrarapid freezing on meiotic and mitotic spindles of mouse oocytes and embryos. Gamete Res 1988; 21:385-401. [PMID: 3220431 DOI: 10.1002/mrd.1120210407] [Citation(s) in RCA: 86] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Preovulatory mouse oocytes and 2-cell embryos were frozen with dimethyl sulfoxide and propanediol by an ultrarapid method. The survival of frozen oocytes was low (33-34%) compared to that of 2-cell embryos (78-79%) with either cryoprotectant. Development to blastocysts after postthaw culture was about 7-15% for oocytes and 79-80% for the embryos. Ultrarapid freezing preserves cell structure quite well as revealed by electron microscopy, but meiotic oocytes and late 2-cell embryos undergoing mitosis showed evidence of spindle disorganization involving loss or clumping of microtubules resulting in some scattering of chromosomes. Embryos developed from frozen eggs showed clear evidence of micronuclear formation and incomplete incorporation of chromosomal material into main nuclei. These experiments confirm our observations on freezing of human oocytes and show that spindle microtubules are sensitive to freeze-thawing and that cryopreservation could cause chromosomal aberrations during early development. A cautious approach to the introduction of oocyte freezing in human in vitro fertilization (IVF) programs is advocated.
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Affiliation(s)
- A H Sathananthan
- Department of Obstetrics and Gynaecology, National University Hospital, Singapore
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47
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Ng SC, Sathananthan H, Bongso A, Lee MN, Mok H, Wong PC, Ratnam SS. The use of amniotic fluid and serum with propanediol in freezing of murine 2-cell embryos. Fertil Steril 1988; 50:510-3. [PMID: 3410102] [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: 01/05/2023]
Abstract
Human and mouse embryos have been cultured in amniotic fluid (AF). Human AF and human serum (HS) are used in the freeze-thaw of 2-cell mouse embryos. Two hundred seventy-five 2-cell embryos were collected into phosphate-buffered saline with 20% HS and 20% AF and into 100% HS and AF. The embryos were cooled with propanediol as cryoprotectant at a controlled rate. After thaw, they were cultured in T6 with 3 mg/ml bovine serum albumin. Blastocyst formation post-thaw was 56/79, 44/70, 51/61, and 56/79 of intact embryos from 20% HS, 20% AF, pure HS, and pure AF (NS). But blastocyst hatching was better from embryos frozen in pure HS (22/61, compared with 16/79 for 20% HS; P less than 0.05). Hence there is no advantage in using AF in freeze-thaw, but pure HS may be of use.
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Affiliation(s)
- S C Ng
- Department of Obstetrics and Gynaecology, National University Hospital, Singapore
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48
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Ng SC, Sathananthan AH, Wong PC, Ratnam SS, Ho J, Mok H, Lee MN. Fine structure of early human embryos frozen with 1,2 propanediol. Gamete Res 1988; 19:253-63. [PMID: 3198051 DOI: 10.1002/mrd.1120190305] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Previous studies by a French group (Fertil Steril 44:645-651, 1985) have shown that two- to eight-cell human embryos can survive slow freeze-thawing with propanediol in a biological freezer. These embryos were assessed for morphological appearance by phase-contrast microscopy. We assessed the structure of 25 frozen-thawed one- to 12-cell embryos, obtained from our in vitro fertilization (IVF) and GIFT programmes, by phase-contrast and electron microscopy, using the same method of cryopreservation. One-fourth of the embryos examined had all cells intact, and more than one-half the embryos had over 50% of their cells well preserved. Some of these embryos had unequal blastomeres and cytoplasmic fragments. Ultrastructural assessment revealed good preservation of fine structure in the intact blastomeres of all embryos and maintenance of cell-to-cell contacts. Most cytoplasmic organelles, cell membranes, and nuclei were well preserved compared to nonfrozen controls. The cells that were cryoinjured showed varying degrees of disorganization of the cell membrane, cytosol, and cellular membranes, including swelling and disruption of the nuclear envelope. Disruption of the zona was somewhat rare. Small cytoplasmic fragments were less prone to cryoinjury than blastomeres. The use of propanediol for embryo cryopreservation seems to be feasible; frozen embryos with more than 50% cells intact have produced 10 pregnancies after embryo transfer (Fertil Steril 46:268-272, 1986). Replacement of 17 frozen embryos in seven patients has resulted in a twin pregnancy in Singapore. However, the effects of freezing on the mitotic spindles of embryonic cells need to be investigated further.
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Affiliation(s)
- S C Ng
- Department of Obstetrics and Gynecology, National University Hospital, Singapore
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