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Kang H, Kim J, Park CH, Jeong B, So I. Direct modulation of TRPC ion channels by Gα proteins. Front Physiol 2024; 15:1362987. [PMID: 38384797 PMCID: PMC10880550 DOI: 10.3389/fphys.2024.1362987] [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: 12/29/2023] [Accepted: 01/26/2024] [Indexed: 02/23/2024] Open
Abstract
GPCR-Gi protein pathways are involved in the regulation of vagus muscarinic pathway under physiological conditions and are closely associated with the regulation of internal visceral organs. The muscarinic receptor-operated cationic channel is important in GPCR-Gi protein signal transduction as it decreases heart rate and increases GI rhythm frequency. In the SA node of the heart, acetylcholine binds to the M2 receptor and the released Gβγ activates GIRK (I(K,ACh)) channel, inducing a negative chronotropic action. In gastric smooth muscle, there are two muscarinic acetylcholine receptor (mAChR) subtypes, M2 and M3. M2 receptor activates the muscarinic receptor-operated nonselective cationic current (mIcat, NSCC(ACh)) and induces positive chronotropic effect. Meanwhile, M3 receptor induces hydrolysis of PIP2 and releases DAG and IP3. This IP3 increases intracellular Ca2+ and then leads to contraction of GI smooth muscles. The activation of mIcat is inhibited by anti-Gi/o protein antibodies in GI smooth muscle, indicating the involvement of Gαi/o protein in the activation of mIcat. TRPC4 channel is a molecular candidate for mIcat and can be directly activated by constitutively active Gαi QL proteins. TRPC4 and TRPC5 belong to the same subfamily and both are activated by Gi/o proteins. Initial studies suggested that the binding sites for G protein exist at the rib helix or the CIRB domain of TRPC4/5 channels. However, recent cryo-EM structure showed that IYY58-60 amino acids at ARD of TRPC5 binds with Gi3 protein. Considering the expression of TRPC4/5 in the brain, the direct G protein activation on TRPC4/5 is important in terms of neurophysiology. TRPC4/5 channels are also suggested as a coincidence detector for Gi and Gq pathway as Gq pathway increases intracellular Ca2+ and the increased Ca2+ facilitates the activation of TRPC4/5 channels. More complicated situation would occur when GIRK, KCNQ2/3 (IM) and TRPC4/5 channels are co-activated by stimulation of muscarinic receptors at the acetylcholine-releasing nerve terminals. This review highlights the effects of GPCR-Gi protein pathway, including dopamine, μ-opioid, serotonin, glutamate, GABA, on various oragns, and it emphasizes the importance of considering TRPC4/5 channels as crucial players in the field of neuroscience.
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Affiliation(s)
- Hana Kang
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jinhyeong Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Christine Haewon Park
- Department of Physiology, University of California, San Francisco, San Francisco, CA, United States
| | - Byeongseok Jeong
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Insuk So
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
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Jeong B, Song YP, Chung JY, Park KC, Kim JH, So I, Hong C. Low concentrations of tricyclic antidepressants stimulate TRPC4 channel activity by acting as an opioid receptor ligand. Am J Physiol Cell Physiol 2023. [PMID: 37154492 DOI: 10.1152/ajpcell.00535.2022] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Traditionally prescribed for mood disorders, tricyclic antidepressants (TCAs) have shown promising therapeutic effects on chronic neuralgia and irritable bowel syndrome. However, the mechanism by which these atypical effects manifest is unclear. Among the proposed mechanisms is the well-known pain-related inhibitory G-protein coupled receptor (GiPCR), namely, the opioid receptor (OR). Here, we confirmed that TCA indeed stimulates OR and regulates the gating of TRPC4, a downstream signaling of the Gi-pathway. In an ELISA to quantify the amount of intracellular cAMP, a downstream product of OR/Gi-pathway, treatment with amitriptyline (AMI) showed a decrease in [cAMP]i similar to that of the μOR agonist. Next, we explored the binding site of TCA by modeling the previously revealed ligand-bound structure of μOR. A conserved aspartate residue of ORs was predicted to participate in salt bridge interaction with the amine group of TCAs, and in aspartate-to-arginine mutation, AMI did not decrease the FRET-based binding efficiency between the ORs and Gαi2. As an alternative way to monitor the downstream signaling of Gi-pathway, we evaluated the functional activity of TRPC4 channel, as it is well known to be activated by Gαi. TCAs increased the TRPC4 current through ORs, and TCA-evoked TRPC4 activation was abolished by an inhibitor of Gαi2 or its dominant-negative mutant. As expected, TCA-evoked activation of TRPC4 was not observed in the aspartate mutants of OR. Taken together, OR could be proclaimed as a promising target among numerous binding partners of TCA, and TCA-evoked TRPC4 activation may help to explain the nonopioid analgesic effect of TCA.
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Affiliation(s)
- Byeongseok Jeong
- Department of Physiology, College of Medicine, Seoul National University, Seoul, South Korea
- Department of Physiology, Chosun University College of Medicine, Kwangju, South Korea
| | - Young Pyo Song
- Department of Physiology, Chosun University College of Medicine, Kwangju, South Korea
| | - Ji Yeon Chung
- Department of Neurology, Chosun University College of Medicine, Kwangju, South Korea
| | - Ki Chul Park
- OZIWORX. R&D Laboratory, 130-2, Donghwagongdan-ro, Wonju-si, Gangwon-do, South Korea
| | - Jin Hyeong Kim
- Department of Physiology, College of Medicine, Seoul National University, Seoul, South Korea
| | - Insuk So
- Department of Physiology, College of Medicine, Seoul National University, Seoul, South Korea
- Department of Physiology and Institute of Dermatological Science, Seoul National University College of Medicine, Seoul, South Korea
| | - Chansik Hong
- Department of Physiology, Chosun University College of Medicine, Kwangju, South Korea
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Won J, Kim J, Jeong H, Kim J, Feng S, Jeong B, Kwak M, Ko J, Im W, So I, Lee HH. Molecular architecture of the Gα i-bound TRPC5 ion channel. Nat Commun 2023; 14:2550. [PMID: 37137991 PMCID: PMC10156788 DOI: 10.1038/s41467-023-38281-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 04/21/2023] [Indexed: 05/05/2023] Open
Abstract
G-protein coupled receptors (GPCRs) and ion channels serve as key molecular switches through which extracellular stimuli are transformed into intracellular effects, and it has long been postulated that ion channels are direct effector molecules of the alpha subunit of G-proteins (Gα). However, no complete structural evidence supporting the direct interaction between Gα and ion channels is available. Here, we present the cryo-electron microscopy structures of the human transient receptor potential canonical 5 (TRPC5)-Gαi3 complexes with a 4:4 stoichiometry in lipid nanodiscs. Remarkably, Gαi3 binds to the ankyrin repeat edge of TRPC5 ~ 50 Å away from the cell membrane. Electrophysiological analysis shows that Gαi3 increases the sensitivity of TRPC5 to phosphatidylinositol 4,5-bisphosphate (PIP2), thereby rendering TRPC5 more easily opened in the cell membrane, where the concentration of PIP2 is physiologically regulated. Our results demonstrate that ion channels are one of the direct effector molecules of Gα proteins triggered by GPCR activation-providing a structural framework for unraveling the crosstalk between two major classes of transmembrane proteins: GPCRs and ion channels.
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Affiliation(s)
- Jongdae Won
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jinsung Kim
- Department of Physiology, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Hyeongseop Jeong
- Center for Research Equipment, Korea Basic Science Institute, Chungcheongbuk-do, 28119, Republic of Korea
| | - Jinhyeong Kim
- Department of Physiology, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Shasha Feng
- Department of Biological Sciences and Chemistry, Lehigh University, Bethlehem, PA, 18015, USA
| | - Byeongseok Jeong
- Department of Physiology, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Misun Kwak
- Department of Physiology, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Juyeon Ko
- Department of Physiology, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
- Department of Physiology, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Wonpil Im
- Department of Biological Sciences and Chemistry, Lehigh University, Bethlehem, PA, 18015, USA
| | - Insuk So
- Department of Physiology, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea.
| | - Hyung Ho Lee
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
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Jeong B, Sung TS, Jeon D, Park KJ, Jun JY, So I, Hong C. Inhibition of TRPC4 channel activity in colonic myocytes by tricyclic antidepressants disrupts colonic motility causing constipation. J Cell Mol Med 2022; 26:4911-4923. [PMID: 35560982 PMCID: PMC9549500 DOI: 10.1111/jcmm.17348] [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: 11/03/2021] [Revised: 03/28/2022] [Accepted: 04/05/2022] [Indexed: 11/27/2022] Open
Abstract
Tricyclic antidepressants (TCAs) have been used to treat depression and were recently approved for treating irritable bowel syndrome (IBS) patients with severe or refractory IBS symptoms. However, the molecular mechanism of TCA action in the gastrointestinal (GI) tract remains poorly understood. Transient receptor potential channel canonical type 4 (TRPC4), which is a Ca2+‐permeable nonselective cation channel, is a critical regulator of GI excitability. Herein, we investigated whether TCA modulates TRPC4 channel activity and which mechanism in colonic myocytes consequently causes constipation. To prove the clinical benefit in patients with diarrhoea caused by TCA treatment, we performed mechanical tension recording of repetitive motor pattern (RMP) in segment, electric field stimulation (EFS)‐induced and spontaneous contractions in isolated muscle strips. From these recordings, we observed that all TCA compounds significantly inhibited contractions of colonic motility in human. To determine the contribution of TRPC4 to colonic motility, we measured the electrical activity of heterologous or endogenous TRPC4 by TCAs using the patch clamp technique in HEK293 cells and murine colonic myocytes. In TRPC4‐overexpressed HEK cells, we observed TCA‐evoked direct inhibition of TRPC4. Compared with TRPC4‐knockout mice, we identified that muscarinic cationic current (mIcat) was suppressed through TRPC4 inhibition by TCA in isolated murine colonic myocytes. Collectively, we suggest that TCA action is responsible for the inhibition of TRPC4 channels in colonic myocytes, ultimately causing constipation. These findings provide clinical insights into abnormal intestinal motility and medical interventions aimed at IBS therapy.
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Affiliation(s)
- Byeongseok Jeong
- Department of Physiology, Chosun University School of Medicine, Gwangju, South Korea
| | - Tae Sik Sung
- Department of Surgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, South Korea.,Biomedical Research Institute, Seoul National University Hospital, Seoul, South Korea
| | - Dongju Jeon
- Department of Physiology, Chosun University School of Medicine, Gwangju, South Korea
| | - Kyu Joo Park
- Department of Surgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, South Korea
| | - Jae Yeoul Jun
- Department of Physiology, Chosun University School of Medicine, Gwangju, South Korea
| | - Insuk So
- Department of Physiology and Institute of Dermatological Science, Seoul National University College of Medicine, Seoul, South Korea
| | - Chansik Hong
- Department of Physiology, Chosun University School of Medicine, Gwangju, South Korea
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Ko YJ, Sohn HM, Jang Y, Park M, Kim B, Kim B, Park J, Hyun H, Jeong B, Hong C, Lim W. A novel modified RANKL variant can prevent osteoporosis by acting as a vaccine and an inhibitor. Clin Transl Med 2021; 11:e368. [PMID: 33784004 PMCID: PMC7967917 DOI: 10.1002/ctm2.368] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 01/11/2021] [Revised: 02/25/2021] [Accepted: 03/05/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The discovery of receptor activator of nuclear factor-ĸB ligand (RANKL) as the final effector in the pathogenesis of osteoporosis has led to a better understanding of bone remodeling. When RANKL binds to its receptor (RANK), osteoclastic differentiation and activation are initiated. Herein, we propose a strategy using a novel RANKL variant as a competitive inhibitor for RANKL. The RANKL variant activates LGR4 signaling, which competitively regulates RANK and acts as an immunogen that induces anti-RANKL antibody production. METHODS We modified the RANK-binding site on RANKL using minimal amino acid changes in the RANKL complex and its counterpart receptor RANK and tried to evaluate the inhibitory effects on osteoclastogenesis. RESULTS The novel RANKL variant did not bind RANK in osteoclast progenitor cells, but activated LGR4 through the GSK3-β signaling pathway, thereby suppressing activated T cell cytoplasmic nuclear factor calcineurin-dependent 1 (NFATc1) expression and activity during osteoclastogenesis. Our RANKL variant generated high levels of RANKL-specific antibodies, blocked osteoclastogenesis, and inhibited osteoporosis in ovariectomized mouse models. Generated anti-RANKL antibodies showed a high inhibitory effect on osteoclastogenesis in vivo and in vitro. CONCLUSIONS We observed that the novel RANKL indeed blocks RANKL via LGR4 signaling and generates anti-RANKL antibodies, demonstrating an innovative strategy in the development of general immunotherapy.
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Affiliation(s)
- Young Jong Ko
- Laboratory of Orthopaedic ResearchChosun University HospitalDong‐GuGwangjuRepublic of Korea
- Department of Orthopaedic SurgeryChosun University HospitalDong‐GuGwangjuRepublic of Korea
| | - Hong Moon Sohn
- Laboratory of Orthopaedic ResearchChosun University HospitalDong‐GuGwangjuRepublic of Korea
- Department of Orthopaedic SurgeryChosun University HospitalDong‐GuGwangjuRepublic of Korea
| | - Yuria Jang
- Laboratory of Orthopaedic ResearchChosun University HospitalDong‐GuGwangjuRepublic of Korea
- Department of Orthopaedic SurgeryChosun University HospitalDong‐GuGwangjuRepublic of Korea
| | - Mineon Park
- Laboratory of Orthopaedic ResearchChosun University HospitalDong‐GuGwangjuRepublic of Korea
- Department of Orthopaedic SurgeryChosun University HospitalDong‐GuGwangjuRepublic of Korea
| | - Bora Kim
- Laboratory of Orthopaedic ResearchChosun University HospitalDong‐GuGwangjuRepublic of Korea
- Department of Orthopaedic SurgeryChosun University HospitalDong‐GuGwangjuRepublic of Korea
| | - Beomchang Kim
- Laboratory of Orthopaedic ResearchChosun University HospitalDong‐GuGwangjuRepublic of Korea
- Department of Orthopaedic SurgeryChosun University HospitalDong‐GuGwangjuRepublic of Korea
| | - Jae‐Il Park
- Korea Basic Science InstituteGwangju Center at Chonnam National UniversityGwangjuRepublic of Korea
| | - Hoon Hyun
- Department of Biomedical Sciences Chonnam National University Medical SchoolGwangjuRepublic of Korea
| | - Byeongseok Jeong
- Department of PhysiologySchool of MedicineChosun UniversityGwangjuRepublic of Korea
| | - Chansik Hong
- Department of PhysiologySchool of MedicineChosun UniversityGwangjuRepublic of Korea
| | - Wonbong Lim
- Laboratory of Orthopaedic ResearchChosun University HospitalDong‐GuGwangjuRepublic of Korea
- Department of Orthopaedic SurgeryChosun University HospitalDong‐GuGwangjuRepublic of Korea
- Department of Premedical ScienceCollege of MedicineChosun UniversityDong‐GuGwangjuRepublic of Korea
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Wang W, Schock BC, Abdala-Valencia H, Jeong B, Bale S, Christmann R, Marangoni R, Berdnikovs S, Herzog E, Varga J, Bhattacharyya S. 803 A20 and its repressor DREAM expression govern susceptibility to fibrosis in systemic sclerosis. J Invest Dermatol 2020. [DOI: 10.1016/j.jid.2020.03.818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Suzuki M, Ramezanpour M, Cooksley C, Lee T, Jeong B, Kao S, Suzuki T, Psaltis A, Nakamaru Y, Homma A, Wormald P, Vreugde S. Zinc-depletion associates with tissue eosinophilia and collagen depletion in chronic rhinosinusitis. Rhinology 2020; 58:451-459. [DOI: 10.4193/rhin19.383] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Hong C, Jeong B, Park HJ, Chung JY, Lee JE, Kim J, Shin YC, So I. TRP Channels as Emerging Therapeutic Targets for Neurodegenerative Diseases. Front Physiol 2020; 11:238. [PMID: 32351395 PMCID: PMC7174697 DOI: 10.3389/fphys.2020.00238] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [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: 12/20/2019] [Accepted: 03/02/2020] [Indexed: 12/12/2022] Open
Abstract
The development of treatment for neurodegenerative diseases (NDs) such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and amyotrophic lateral sclerosis is facing medical challenges due to the increasingly aging population. However, some pharmaceutical companies have ceased the development of therapeutics for NDs, and no new treatments for NDs have been established during the last decade. The relationship between ND pathogenesis and risk factors has not been completely elucidated. Herein, we review the potential involvement of transient receptor potential (TRP) channels in NDs, where oxidative stress and disrupted Ca2+ homeostasis consequently lead to neuronal apoptosis. Reactive oxygen species (ROS) -sensitive TRP channels can be key risk factors as polymodal sensors, since progressive late onset with secondary pathological damage after initial toxic insult is one of the typical characteristics of NDs. Recent evidence indicates that the dysregulation of TRP channels is a missing link between disruption of Ca2+ homeostasis and neuronal loss in NDs. In this review, we discuss the latest findings regarding TRP channels to provide insights into the research and quests for alternative therapeutic candidates for NDs. As the structures of TRP channels have recently been revealed by cryo-electron microscopy, it is necessary to develop new TRP channel antagonists and reevaluate existing drugs.
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Affiliation(s)
- Chansik Hong
- Department of Physiology, Chosun University School of Medicine, Gwangju, South Korea
| | - Byeongseok Jeong
- Department of Physiology, Chosun University School of Medicine, Gwangju, South Korea
| | - Hyung Joon Park
- Department of Physiology, Chosun University School of Medicine, Gwangju, South Korea
| | - Ji Yeon Chung
- Department of Neurology, Chosun University School of Medicine, Gwangju, South Korea
| | - Jung Eun Lee
- Department of Physiology and Institute of Dermatological Science, Seoul National University College of Medicine, Seoul, South Korea
| | - Jinsung Kim
- Department of Physiology and Institute of Dermatological Science, Seoul National University College of Medicine, Seoul, South Korea
| | - Young-Cheul Shin
- Department of Cell Biology, Harvard Medical School, Boston, MA, United States
| | - Insuk So
- Department of Physiology and Institute of Dermatological Science, Seoul National University College of Medicine, Seoul, South Korea
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Hong C, Choi SH, Kwak M, Jeong B, Ko J, Park HJ, Choi S, Jun JY, So I. TRPC5 channel instability induced by depalmitoylation protects striatal neurons against oxidative stress in Huntington's disease. Biochim Biophys Acta Mol Cell Res 2019; 1867:118620. [PMID: 31812495 DOI: 10.1016/j.bbamcr.2019.118620] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 11/26/2019] [Accepted: 11/30/2019] [Indexed: 12/15/2022]
Abstract
Protein S-palmitoylation, the covalent lipid modification of the side chain of Cys residues with the 16‑carbon fatty acid palmitate, is the most common acylation, and it enhances the membrane stability of ion channels. This post-translational modification (PTM) determines a functional mechanism of ion channel life cycle from maturation and membrane trafficking to localization. Especially, neurodevelopment is regulated by balancing the level of synaptic protein palmitoylation/depalmitoylation. Recently, we revealed the pathological role of the transient receptor potential canonical type 5 (TRPC5) channel in striatal neuronal loss during Huntington's disease (HD), which is abnormally activated by oxidative stress. Here, we report a mechanism of TRPC5 palmitoylation at a conserved cysteine residue, that is critical for intrinsic channel activity. Furthermore, we identified the therapeutic effect of TRPC5 depalmitoylation by enhancing the TRPC5 membrane instability on HD striatal cells in order to lower TRPC5 toxicity. Collectively, these findings suggest that controlling S-palmitoylation of the TRPC5 channel as a potential risk factor can modulate TRPC5 channel expression and activity, providing new insights into a therapeutic strategy for neurodegenerative diseases.
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Affiliation(s)
- Chansik Hong
- Department of Physiology, Chosun University School of Medicine, Kwangju 61452, South Korea.
| | - Seo Hwa Choi
- Department of Physiology, Chosun University School of Medicine, Kwangju 61452, South Korea
| | - Misun Kwak
- Department of Physiology and Institute of Dermatological Science, Seoul National University College of Medicine, Seoul 03080, South Korea
| | - Byeongseok Jeong
- Department of Physiology, Chosun University School of Medicine, Kwangju 61452, South Korea
| | - Juyeon Ko
- Department of Physiology and Institute of Dermatological Science, Seoul National University College of Medicine, Seoul 03080, South Korea
| | - Hyung Joon Park
- Department of Physiology, Chosun University School of Medicine, Kwangju 61452, South Korea
| | - Seok Choi
- Department of Physiology, Chosun University School of Medicine, Kwangju 61452, South Korea
| | - Jae Yeoul Jun
- Department of Physiology, Chosun University School of Medicine, Kwangju 61452, South Korea
| | - Insuk So
- Department of Physiology and Institute of Dermatological Science, Seoul National University College of Medicine, Seoul 03080, South Korea.
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Park S, Jeong B, Shin JH, Kim JH, Kim JW, Gwon DI, Ko GY, Chen CS. Interventional treatment of arterial injury during blind central venous catheterisation in the upper thorax: experience from two centres. Clin Radiol 2019; 75:158.e1-158.e7. [PMID: 31711638 DOI: 10.1016/j.crad.2019.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/03/2019] [Indexed: 12/01/2022]
Abstract
AIM To evaluate the safety and clinical efficacy of interventional treatment for arterial injury during blind, central venous catheterisation in the upper thorax at two tertiary medical centres. MATERIALS AND METHODS Eighteen consecutive patients (37-81 years; M:F=8:10) who underwent interventional treatment for the arterial injuries that occurred during central venous catheterisation without any imaging guidance between November 2007 and December 2018 were included. Clinical data, angiographic findings, detailed interventional procedures, and technical and clinical outcomes were analysed retrospectively. RESULTS Arterial injury sites were the subclavian artery/branches (n=12), axillary artery/branches (n=2), and common carotid artery (n=4). The target vein was not correlated with the corresponding artery/branches in eight patients (44.4%); internal jugular vein to subclavian artery branches. Angiographic findings were pseudoaneurysm (66.7%, 12/18), contrast medium extravasation (22.2%, 4/18), or both (11.1%, n=2). A stent graft was inserted for the main trunk injuries in nine patients, with (n=2) or without (n=7) prior arterial branch embolisation to prevent potential endoleak, while embolisation for the arterial branch injuries was performed in nine patients. Direct percutaneous access with thrombin injection to the pseudoaneurysm or residual arteriovenous fistula was utilised in two. The technical and clinical success rate was 94.4% (17/18) each. There were no procedure-related complications. In one patient without immediate clinical success, there was a persistent pseudoaneurysm after stent graft placement, which was treated with in-stent balloon dilation. CONCLUSION Interventional treatment serves as a safe and effective treatment modality for inadvertent arterial injury related to blind, central venous access catheterisation in the upper thorax.
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Affiliation(s)
- S Park
- Department of Radiology, Gachon University Gil Medical Centre, 21, Namdong-daero 774beon-gil, Namdong-gu, Incheon, South Korea
| | - B Jeong
- Department of Radiology and Research Institute of Radiology, Asan Medical Centre, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, South Korea
| | - J H Shin
- Department of Radiology and Research Institute of Radiology, Asan Medical Centre, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, South Korea.
| | - J H Kim
- Department of Radiology, Gachon University Gil Medical Centre, 21, Namdong-daero 774beon-gil, Namdong-gu, Incheon, South Korea
| | - J W Kim
- Department of Radiology and Research Institute of Radiology, Asan Medical Centre, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, South Korea
| | - D I Gwon
- Department of Radiology and Research Institute of Radiology, Asan Medical Centre, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, South Korea
| | - G-Y Ko
- Department of Radiology and Research Institute of Radiology, Asan Medical Centre, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, South Korea
| | - C S Chen
- Department of Radiology, The Affiliated Cancer Hospital of Zhengzhou University, 1 Jianshe E Rd, Erqi Qu, Zhengzhou Shi, Henan Sheng, PR China
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Park H, Shin K, Kim J, Ahn S, Kim S, Kim Y, Park W, Kim Y, Shin S, Kim J, Lee S, Kim K, Park K, Jeong B. PV-0235: Is there a subset who benefits from PMRT in node-negative breast cancer patients? Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)30678-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Abstract
An investigation of the foaming behavior of polybutylene terephthalate (PBT) resins in extrusion is performed. Commercial grades of PBT with different molecular weights and rheological characteristics are chosen. PBTs with a high temperature chemical blowing agent are extruded under different material and operational conditions (e.g., amount of blowing agent, set temperature at the die, screw RPM, etc.) to allow the understanding of the effects of those conditions on product characteristics. The foamed extrudates are analyzed for density, morphology, and crystallinity. It is shown that the foaming behavior and the foam quality of PBT are functions of the characteristic properties of the resins including rheological and crystallization behavior.
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Affiliation(s)
- B. Jeong
- Otto H. York Department of Chemical Engineering, NJIT, Newark, NJ, USA
| | - M. Xanthos
- Otto H. York Department of Chemical Engineering, NJIT, Newark, NJ, USA, Polymer Processing Institute, GITC Bldg., Suite 3901, NJIT, Newark, NJ 07102, USA,
| | - Y. Seo
- Polymer Processing Technology Team, Tech Center, LG Chemical Ltd., Taejeon, Korea
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13
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Jeong H, Kang K, Jeong B, Chai G, Ha I. Estimation of Optimal Margin for Intrafraction Movements During Frameless Brain Radiosurgery. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.1797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Jeong B, Choi D, Huh S, Park W, Bae D, Kim B. Characteristics and Prognosis of Patients With Cervical Cancer Who Show an Unusual Level of Squamous Cell Carcinoma Antigen at Diagnosis or Recurrence. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.1183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Jeong H, Kang K, Chai G, Jeong B, Ha I, Lim Y. A Dosimetric Effects of 4-dimensional and Monte Carlo Calculation Methods on Treatment Plans for Mobile Lung Cancer in Robotic Radiosurgery. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.2304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Kang K, Lim Y, Jeong H, Ha I, Jeong B, Jang H, Choi B, Chai G. Preliminary Report of Stereotactic Body Radiation Therapy With Respiratory Motion Tracking for Liver Tumors. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Eun D, Choi J, Choi Y, Jeong B, Shin K, Park J. Pregnancy Outcome after Laparoscopic Myomectomy of Large Submucosal Leiomyoma. J Minim Invasive Gynecol 2010. [DOI: 10.1016/j.jmig.2010.08.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Eun D, Choi J, Choi Y, Jeong B, Shin K, Park J. Is the Multifocal Myolysis with RF Simultaniously during Laparoscopic Myomectomy Useful and Safe for Symptomatic Multiple Leiomyomas? J Minim Invasive Gynecol 2010. [DOI: 10.1016/j.jmig.2010.08.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Eun D, Choi J, Choi Y, Jeong B, Shin K, Park J. Analysis on Comparing of Laparoscopic Resection and Myolysis of Adenomyosis with RF to Laparoscopically Supracervical Hysterectomy for the Relief of Symptom of Adenomyosis. J Minim Invasive Gynecol 2010. [DOI: 10.1016/j.jmig.2010.08.625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Eun D, Choi J, Choi Y, Jeong B, Shin K, Park J. Analysis on Results of Salpingosalpingostomy in the Cases of Tubal Pregnancy and Tubal Ligation. J Minim Invasive Gynecol 2010. [DOI: 10.1016/j.jmig.2010.08.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Eun D, Choi J, Choi Y, Jeong B, Shin K, Park J. Analysis on Comparing of Laparoscopic Reduction and Myolysis of Adenomyosis with RF to Laparoscopically Supracervical Hysterectomy for the Relief of Symptom of Adenomyosis. J Minim Invasive Gynecol 2010. [DOI: 10.1016/j.jmig.2010.08.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lee HJ, Kim SY, Kim GS, Hwang JY, Kim YJ, Jeong B, Kim TH, Park EK, Lee SH, Kim HL, Koh JM, Lee JY. Fracture, bone mineral density, and the effects of calcitonin receptor gene in postmenopausal Koreans. Osteoporos Int 2010; 21:1351-60. [PMID: 19946674 DOI: 10.1007/s00198-009-1106-8] [Citation(s) in RCA: 10] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 09/09/2009] [Indexed: 10/20/2022]
Abstract
SUMMARY In a candidate gene association study, we found that the variations of calcitonin receptor (CALCR) gene were related to the risk of vertebral fracture and increased bone mineral density (BMD). INTRODUCTION Calcitonins through calcitonin receptors inhibit osteoclast-mediated bone resorption and modulate calcium ion excretion by the kidney and also prevent vertebral bone loss in early menopause. METHODS To identify genetically susceptible factors of osteoporosis, we discovered the variations in CALCR gene, genotyped in Korean postmenopausal women (n = 729), and examined the potential involvement of seven single-nucleotide polymorphism (SNPs) and their haplotypes in linkage disequilibrium block (BL_hts). RESULTS The SNPs, +43147G > C (intron 7), +60644C > T (exon13, 3' untranslated region), and their haplotypes, BL2_ht1 and BL2_ht2, showed a significant association with risk of vertebral fracture (p = 0.048-0.004) and BL2_ht1 showed a highly significant protective effect. Moreover, the polymorphism +60644C > T showed a highly significant association with BMD at both lumbar spine and femoral neck. The subjects carrying CC and CT genotypes with the SNP, +60644C > T, had higher BMD values at the lumbar spine (p = 0.01-0.001) and femoral neck (p = 0.025-0.009). CONCLUSION These results indicate that the CALCR gene may regulate bone metabolism, and +60644C > T in the CALCR gene may genetically modulate bone phenotype.
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Affiliation(s)
- H-J Lee
- The Center for Genome Science, National Institute of Health, 5 Nokbun-dong, Eunpyung-gu, Seoul, 122-701, Republic of Korea
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Kang K, Kim H, Jeong B, Lee S, Moon S, Choi B, Jang H, Chang K, Chai G. Effect of Recombinant Human Epidermal Growth Factor from Radiation-induced Intestinal Damage in Mice. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.1264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kang K, Kim H, Chai G, Lee S, Jang K, Choi B, Jang H, Jeong B, Na J. Effect of Cisplatin and Radiotherapy Induced Oral Mucositis by Recombinant Human Epidermal Growth Factor in Mice. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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25
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Jeong B. Catalytic dehydrogenation of cyclohexane in an FAU-type zeolite membrane reactor. J Memb Sci 2003. [DOI: 10.1016/s0376-7388(03)00373-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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26
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Abstract
Recently, tissue engineering approaches using injectable, in situ gel forming systems have been reported. In this review, the gelation processes and several injectable systems that exhibit in situ gel formation at physiological conditions are discussed. Applications of selected injectable systems (alginate, chitosan, hyaluronan, polyethylene oxide/polypropylene oxide) in tissue engineering are also described. Injectable polymer formulation can gel in vivo in response to temperature change (thermal gelation), pH change, ionic cross-linking, or solvent exchange. Kinetics of gelation is directly affected by its mechanism. Injectable formulations offer specific advantages over preformed scaffolds such as: possibility of a minimally invasive implantation, an ability to fill a desired shape, and easy incorporation of various therapeutic agents. Several factors need to be considered before an injectable gel can be selected as a candidate for tissue engineering applications. Apart from tissue-specific cell-matrix interactions, the following gel properties need to be considered: gelation kinetics, matrix resorption rate, possible toxicity of degradation products and their elimination routes, and finally possible interference of the gel matrix with histogenesis.
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Affiliation(s)
- A Gutowska
- Pacific Northwest National Laboratory, Richland, Washington 99352, USA. anna
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Abstract
The molecular mechanism(s) responsible for posttranscriptional gene silencing and RNA interference remain poorly understood. We have cloned a gene (Mut6) from the unicellular green alga Chlamydomonas reinhardtii that is required for the silencing of a transgene and two transposon families. Mut6 encodes a protein that is highly homologous to RNA helicases of the DEAH-box family. This protein is necessary for the degradation of certain aberrant RNAs, such as improperly processed transcripts, which are often produced by transposons and some transgenes.
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Affiliation(s)
- D Wu-Scharf
- School of Biological Sciences and Plant Science Initiative, University of Nebraska-Lincoln, E211 Beadle Center, Post Office Box 880666, Lincoln, NE 68588, USA
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Lim YB, Han SO, Kong HU, Lee Y, Park JS, Jeong B, Kim SW. Biodegradable polyester, poly[alpha-(4-aminobutyl)-L-glycolic acid], as a non-toxic gene carrier. Pharm Res 2000; 17:811-6. [PMID: 10990199 DOI: 10.1023/a:1007552007765] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE The aim of this study was to develop a non-toxic polymeric gene carrier. For this purpose, biodegradable cationic polymer, poly[alpha-(4-aminobutyl)-L-glycolic acid] (PAGA) was synthesized. PAGA was designed to have ester linkage because polyesters usually show biodegradability. METHODS Degradation of PAGA in an aqueous solution was followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). PAGA/DNA complexes were characterized by gel electrophoresis, atomic force microscopy (AFM), dynamic light scattering (DLS). The transfection was measured by using the beta-galactosidase reporter gene. RESULTS PAGA was degraded in aqueous solution very quickly and the final degradation product was a monomer (L-oxylysine). Formation of self-assembling biodegradable complexes between PAGA and DNA at a charge ratio 1:1 (+/-) was confirmed by gel band shift assay and AFM. In these studies, controlled release of DNA from the complexes could be seen. The complexes showed about 2-fold higher transfection efficiency than DNA complexes of poly-L-lysine (PLL), a structural analogue of PAGA, which is the most commonly used poly-cation for gene delivery. The polymer did not show cytotoxicity, possibly because of its degradability and the biocompatibility of the monomer. CONCLUSIONS The use of the biodegradable poly-cation, PAGA, as a DNA condensing agent will be useful in safe gene delivery.
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Affiliation(s)
- Y B Lim
- School of Chemistry & Molecular Engineering, Seoul National University, Korea
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29
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Abstract
Aqueous solutions of poly(ethylene glycol-b-[DL-lactic acid-co-glycolic acid]-b-ethylene glycol) (PEG-PLGA-PEG) triblock copolymers form a free-flowing sol at room temperature and become a gel at body temperature. In this study, in situ gel formation was investigated in rats. Upon subcutaneous injection of 33 wt % aqueous solutions of PEG-PLGA-PEG triblock copolymer into rats, transparent gels were observed. The gel showed good mechanical strength and the integrity of gels persisted longer than 1 month. The gel underwent degradation by hydrolysis and turned opaque. Degradation study showed preferential mass loss of PEG-rich segment from the in situ formed gel. Number average molecular weight determined by gel permeation chromatography decreased from 3300 to 1900 and 30% mass loss was observed over 1 month.
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Affiliation(s)
- B Jeong
- Biomedical Polymers Research Building, Room 205, CCCD/Pharmaceutics, University of Utah, Salt Lake City, Utah 84112, USA
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Abstract
An aqueous solution of newly developed low-molecular-weight PEG-PLGA-PEG triblock copolymers with a specific composition is a free flowing sol at room temperature but becomes a gel at body temperature. Two model drugs, ketoprofen and spironolatone, which have different hydrophobicities, were released from the PEG-PLGA-PEG triblock copolymer hydrogel formed in situ by injecting the solutions into a 37 degrees C aqueous environment. Ketoprofen (a model hydrophilic drug) was released over 2 weeks with a first-order release profile, while spironolactone (a model hydrophobic drug) was released over 2 months with an S-shaped release profile. The release profiles were simulated by models considering degradation and diffusion, and were better described by a model assuming a core-shell structure of the gel.
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Affiliation(s)
- B Jeong
- Biomedical Polymers Research Building, Room 205, CCCD/Pharmaceutics, University of Utah, Salt Lake City, UT, USA
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31
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Abstract
Many biodegradable polymers were used for drug delivery and some are successful for human application. There remains fabrication problems, such as difficult processability and limited organic solvent and irreproducible drug release kinetics. New star-shaped block copolymers, of which the typical molecular architecture is presented, results from their distinct solution properties, thermal properties and morphology. Their unique physical properties are due to the three-dimensional, hyperbranched molecular architecture and influence microsphere fabrication, drug release and degradation profiles. We recently synthesized thermosensitive biodegradable hydrogel consisting of polyethylene oxide and poly(L-lactic acid). Aqueous solution of these copolymers with proper combination of molecular weights exhibit temperature-dependent reversible sol-gel transition. Desired molecular arrangements provide unique behavior that sol (at low temperature) form gel (at body temperature). The use of these two biodegradable polymers have great advantages for sustained injectable drug delivery systems. The formulation is simple, which is totally free of organic solvent. In sol or aqueous solution state of this polymer solubilized hydrophobic drugs prior to form gel matrix.
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Affiliation(s)
- B Jeong
- Department of Pharmaceutics and Pharmaceutical Chemistry, Center for Controlled Chemical Delivery, University of Utah, Salt Lake City, UT 84112, USA
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32
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Abstract
Available data suggest that drugs should be delivered to a vascular lesion at a high concentration over an extended period of time to control vascular smooth muscle cell (VSMC) proliferation. This study was undertaken to formulate a paclitaxel, an antimicrotubule agent, into a biodegradable poly (ethylene oxide)-poly(lactide/glycolide) (PEO-PLGA) nanosphere as a sustained drug delivery system and to study its effects on VSMC in culture. The paclitaxel-loaded nanospheres (PT/NS), prepared by an emulsion-solvent evaporation method, had an average diameter of approximately 150 nm and showed a sustained release profile over 4 weeks. The PT/NS exhibited antiproliferative effects comparable to those observed with free paclitaxel. The cellular internalization of nanospheres was visualized using confocal fluorescence microscopy, and from a flow cytometry study the progressive cellular uptake profile, uptake inhibition at low temperature, and saturation uptake kinetics (concentration dependency) were observed. These suggest that (adsorptive) pinocytosis is a major uptake mechanism of the nanospheres. The sustained drug release profile and cellular internalization results suggest that nanospheres loaded with paclitaxel may potentially be used as an endocytizable, local sustained drug delivery system for the prevention of restenosis.
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Affiliation(s)
- H Suh
- Department of Pharmaceutics and Pharmaceutical Chemistry/Center for Controlled Chemical Delivery, University of Utah, Salt Lake City 84112-9452, USA
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Affiliation(s)
- H Suh
- Department of Pharmaceutics and Pharmaceutical Chemistry/CCCD, University of Utah, Salt Lake City 84112, USA
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34
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Abstract
Polymers that display a physicochemical response to stimuli are widely explored as potential drug-delivery systems. Stimuli studied to date include chemical substances and changes in temperature, pH and electric field. Homopolymers or copolymers of N-isopropylacrylamide and poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (known as poloxamers) are typical examples of thermosensitive polymers, but their use in drug delivery is problematic because they are toxic and non-biodegradable. Biodegradable polymers used for drug delivery to date have mostly been in the form of injectable microspheres or implant systems, which require complicated fabrication processes using organic solvents. Such systems have the disadvantage that the use of organic solvents can cause denaturation when protein drugs are to be encapsulated. Furthermore, the solid form requires surgical insertion, which often results in tissue irritation and damage. Here we report the synthesis of a thermosensitive, biodegradable hydrogel consisting of blocks of poly(ethylene oxide) and poly(L-lactic acid). Aqueous solutions of these copolymers exhibit temperature-dependent reversible gel-sol transitions. The hydrogel can be loaded with bioactive molecules in an aqueous phase at an elevated temperature (around 45 degrees C), where they form a sol. In this form, the polymer is injectable. On subcutaneous injection and subsequent rapid cooling to body temperature, the loaded copolymer forms a gel that can act as a sustained-release matrix for drugs.
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Affiliation(s)
- B Jeong
- CCCD/Pharmaceutics, University of Utah, Salt Lake City 84112, USA
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