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Kwon A, Kim YS, Kim J, Koo JH. Endoplasmic Reticulum Stress Activates Hepatic Macrophages through PERK-hnRNPA1 Signaling. Biomol Ther (Seoul) 2024; 32:341-348. [PMID: 38589295 PMCID: PMC11063487 DOI: 10.4062/biomolther.2023.174] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 10/13/2023] [Accepted: 10/19/2023] [Indexed: 04/10/2024] Open
Abstract
Endoplasmic reticulum (ER) stress plays a crucial role in liver diseases, affecting various types of hepatic cells. While studies have focused on the link between ER stress and hepatocytes as well as hepatic stellate cells (HSCs), the precise involvement of hepatic macrophages in ER stress-induced liver injury remains poorly understood. Here, we examined the effects of ER stress on hepatic macrophages and their role in liver injury. Acute ER stress led to the accumulation and activation of hepatic macrophages, which preceded hepatocyte apoptosis. Notably, macrophage depletion mitigated liver injury induced by ER stress, underscoring their detrimental role. Mechanistic studies revealed that ER stress stimulates macrophages predominantly via the PERK signaling pathway, regardless of its canonical substrate ATF4. hnRNPA1 has been identified as a crucial mediator of PERK-driven macrophage activation, as the overexpression of hnRNPA1 effectively reduced ER stress and suppressed pro-inflammatory activation. We observed that hnRNPA1 interacts with mRNAs that encode UPR-related proteins, indicating its role in the regulation of ER stress response in macrophages. These findings illuminate the cell type-specific responses to ER stress and the significance of hepatic macrophages in ER stress-induced liver injury. Collectively, the PERK-hnRNPA1 axis has been discovered as a molecular mechanism for macrophage activation, presenting prospective therapeutic targets for inflammatory hepatic diseases such as acute liver injury.
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Affiliation(s)
- Ari Kwon
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
- Department of Pharmacology, Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Yun Seok Kim
- Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Jiyoon Kim
- Department of Pharmacology, Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
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Yu JH, Choi MG, Lee NY, Kwon A, Lee E, Koo JH. Hepatocyte GPCR signaling regulates IRF3 to control hepatic stellate cell transdifferentiation. Cell Commun Signal 2024; 22:48. [PMID: 38233853 PMCID: PMC10795343 DOI: 10.1186/s12964-023-01416-6] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 12/02/2023] [Indexed: 01/19/2024] Open
Abstract
BACKGROUND Interferon Regulatory Factor 3 (IRF3) is a transcription factor that plays a crucial role in the innate immune response by recognizing and responding to foreign antigens. Recently, its roles in sterile conditions are being studied, as in metabolic and fibrotic diseases. However, the search on the upstream regulator for efficient pharmacological targeting is yet to be fully explored. Here, we show that G protein-coupled receptors (GPCRs) can regulate IRF3 phosphorylation through of GPCR-Gα protein interaction. RESULTS IRF3 and target genes were strongly associated with fibrosis markers in liver fibrosis patients and models. Conditioned media from MIHA hepatocytes overexpressing IRF3 induced fibrogenic activation of LX-2 hepatic stellate cells (HSCs). In an overexpression library screening using active mutant Gα subunits and Phos-tag immunoblotting, Gαs was found out to strongly phosphorylate IRF3. Stimulation of Gαs by glucagon or epinephrine or by Gαs-specific designed GPCR phosphorylated IRF3. Protein kinase A (PKA) signaling was primarily responsible for IRF3 phosphorylation and Interleukin 33 (IL-33) expression downstream of Gαs. PKA phosphorylated IRF3 on a previously unrecognized residue and did not require reported upstream kinases such as TANK-binding kinase 1 (TBK1). Activation of Gαs signaling by glucagon induced IL-33 production in hepatocytes. Conditioned media from the hepatocytes activated HSCs, as indicated by α-SMA and COL1A1 expression, and this was reversed by pre-treatment of the media with IL-33 neutralizing antibody. CONCLUSIONS Gαs-coupled GPCR signaling increases IRF3 phosphorylation through cAMP-mediated activation of PKA. This leads to an increase of IL-33 expression, which further contributes to HSC activation. Our findings that hepatocyte GPCR signaling regulates IRF3 to control hepatic stellate cell transdifferentiation provides an insight for understanding the complex intercellular communication during liver fibrosis progression and suggests therapeutic opportunities for the disease. Video Abstract.
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Affiliation(s)
- Jae-Hyun Yu
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Myeung Gi Choi
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Na Young Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ari Kwon
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Euijin Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
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Kwon A, Lee NY, Yu JH, Choi MG, Park J, Koo JH. Mitochondrial stress activates YAP/TAZ through RhoA oxidation to promote liver injury. Cell Death Dis 2024; 15:51. [PMID: 38225223 PMCID: PMC10789791 DOI: 10.1038/s41419-024-06448-5] [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: 10/13/2023] [Revised: 01/03/2024] [Accepted: 01/05/2024] [Indexed: 01/17/2024]
Abstract
Yes-associated protein (YAP) and WW domain-containing transcription regulator protein 1 (WWTR1; also known as TAZ) are the main effectors of the Hippo pathway and their dysregulation contributes to diseases in tissues including the liver. Although mitochondria are capable of transmitting signals to change transcriptomic landscape of diseased hepatocytes, such retrograde signaling and the related nuclear machinery are largely unknown. Here, we show that increased YAP activity is associated with mitochondrial stress during liver injury; and this is required for secondary inflammation, promoting hepatocyte death. Mitochondrial stress inducers robustly promoted YAP/TAZ dephosphorylation, nuclear accumulation, and target gene transcription. RNA sequencing revealed that the majority of mitochondrial stress transcripts required YAP/TAZ. Mechanistically, direct oxidation of RhoA by mitochondrial superoxide was responsible for PP2A-mediated YAP/TAZ dephosphorylation providing a novel physiological input for the Hippo pathway. Hepatocyte-specific Yap/Taz ablation suppressed acetaminophen-induced liver injury and blunted transcriptomic changes associated with the pathology. Our observations uncover unappreciated pathway of mitochondrial stress signaling and reveal YAP/TAZ activation as the mechanistic basis for liver injury progression.
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Affiliation(s)
- Ari Kwon
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Korea
| | - Na Young Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Korea
| | - Jae-Hyun Yu
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Korea
| | - Myeung Gi Choi
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Korea
| | - Jeongwoo Park
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Korea.
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Yu JH, Kim JH, Soung NK, Moon EY, Koo JH. Identification of the primary ciliary proteins IFT38 and IFT144 to enhance serum-mediated YAP activation and cell proliferation. Biochem Biophys Res Commun 2023; 681:186-193. [PMID: 37783116 DOI: 10.1016/j.bbrc.2023.09.082] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 09/25/2023] [Accepted: 09/26/2023] [Indexed: 10/04/2023]
Abstract
Primary cilia are essential cellular antennae that transmit external signals into intracellular responses. These sensory organelles perform crucial tasks in triggering intracellular signaling pathways, including those initiated by G protein-coupled receptors (GPCRs). Given the involvement of GPCRs in serum-induced signaling, we investigated the contribution of ciliary proteins in mitogen perception and cell proliferation. We found that depletion of cilia via IFT88 silencing impaired cell growth and repressed YAP activation against serum and its mitogenic constituents, namely lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P). To identify the key player of serum mitogen signaling, a mutant cell line library with 30 ablated individual ciliary proteins was established and screened based on YAP dephosphorylation and target gene induction. While 9 of them had altered signaling, ablation of IFT38 or IFT144 led to a particularly robust repression of YAP activation upon LPA and S1P. The deficiency of IFT38 and IFT144 attenuated cell proliferation, as corroborated in either 2-dimensional cultures or tumor spheroids. In subcutaneous skin melanoma patients, expression of IFT38 and IFT144 was associated with unfavorable outcomes in overall survival. In conclusion, our study demonstrates the involvement of ciliary proteins in mitogen signaling and identifies the regulatory roles of IFT38 and IFT144 in serum-mediated Hippo pathway signaling and cellular growth.
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Affiliation(s)
- Jae-Hyun Yu
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Jeong Heon Kim
- Department of Bioscience and Biotechnology, Sejong University, Seoul 05006, Republic of Korea
| | - Nak-Kyun Soung
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongju 28116, Republic of Korea
| | - Eun-Yi Moon
- Department of Bioscience and Biotechnology, Sejong University, Seoul 05006, Republic of Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea.
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Yu JH, Moon EY, Kim J, Koo JH. Identification of Small GTPases That Phosphorylate IRF3 through TBK1 Activation Using an Active Mutant Library Screen. Biomol Ther (Seoul) 2023; 31:48-58. [PMID: 36579460 PMCID: PMC9810446 DOI: 10.4062/biomolther.2022.119] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 09/06/2022] [Revised: 09/22/2022] [Accepted: 09/26/2022] [Indexed: 12/30/2022] Open
Abstract
Interferon regulatory factor 3 (IRF3) integrates both immunological and non-immunological inputs to control cell survival and death. Small GTPases are versatile functional switches that lie on the very upstream in signal transduction pathways, of which duration of activation is very transient. The large number of homologous proteins and the requirement for site-directed mutagenesis have hindered attempts to investigate the link between small GTPases and IRF3. Here, we constructed a constitutively active mutant expression library for small GTPase expression using Gibson assembly cloning. Small-scale screening identified multiple GTPases capable of promoting IRF3 phosphorylation. Intriguingly, 27 of 152 GTPases, including ARF1, RHEB, RHEBL1, and RAN, were found to increase IRF3 phosphorylation. Unbiased screening enabled us to investigate the sequence-activity relationship between the GTPases and IRF3. We found that the regulation of IRF3 by small GTPases was dependent on TBK1. Our work reveals the significant contribution of GTPases in IRF3 signaling and the potential role of IRF3 in GTPase function, providing a novel therapeutic approach against diseases with GTPase overexpression or active mutations, such as cancer.
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Affiliation(s)
- Jae-Hyun Yu
- Department of Pharmacology and Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea,College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Eun-Yi Moon
- Department of Bioscience and Biotechnology, Sejong University, Seoul 05006, Republic of Korea
| | - Jiyoon Kim
- Department of Pharmacology and Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea,Corresponding Authors E-mail: (Kim J), (Koo JH), Tel: +82-2-3147-8358 (Kim J), +82-2-880-7839 (Koo JH), Fax: +82-2-536-2485 (Kim J), +82-2-888-9122 (Koo JH)
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea,Corresponding Authors E-mail: (Kim J), (Koo JH), Tel: +82-2-3147-8358 (Kim J), +82-2-880-7839 (Koo JH), Fax: +82-2-536-2485 (Kim J), +82-2-888-9122 (Koo JH)
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Kim A, Koo JH, Lee JM, Joo MS, Kim TH, Kim H, Jun DW, Kim SG. NRF2‐mediated SIRT3 induction protects hepatocytes from ER stress‐induced liver injury. FASEB J 2022; 36:e22170. [DOI: 10.1096/fj.202101470r] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 12/17/2021] [Accepted: 01/07/2022] [Indexed: 01/07/2023]
Affiliation(s)
- Ayoung Kim
- College of Pharmacy and Integrated Research Institute for Drug Development Dongguk University‐Seoul Goyang‐si South Korea
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul South Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul South Korea
| | - Jung Min Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul South Korea
| | - Min Sung Joo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul South Korea
| | - Tae Hyun Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul South Korea
- Research Institute of Pharmaceutical Sciences, College of Pharmacy Sookmyung Women’s University Seoul South Korea
| | - Hyunsung Kim
- Department of Pathology Hanyang University School of Medicine Seoul South Korea
| | - Dae Won Jun
- Internal Medicine Hanyang University School of Medicine Seoul South Korea
| | - Sang Geon Kim
- College of Pharmacy and Integrated Research Institute for Drug Development Dongguk University‐Seoul Goyang‐si South Korea
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Kim A, Koo JH, Jin X, Kim W, Park SY, Park S, Rhee EP, Choi CS, Kim SG. Ablation of USP21 in skeletal muscle promotes oxidative fibre phenotype, inhibiting obesity and type 2 diabetes. J Cachexia Sarcopenia Muscle 2021; 12:1669-1689. [PMID: 34523817 PMCID: PMC8718070 DOI: 10.1002/jcsm.12777] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/25/2021] [Accepted: 07/22/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Skeletal muscle as a metabolic consumer determines systemic energy homeostasis by regulating myofibre type conversion and muscle mass control. Perturbation of the skeletal muscle metabolism elevates the risk of a variety of diseases including metabolic disorders. However, the regulatory pathways and molecules are not completely understood. The discovery of relevant responsible molecules and the associated network could be an attractive strategy to overcome diseases associated with muscle problems. METHODS An initial screening using quantitative trait locus analysis enabled us to extract a set of genes including ubiquitin-specific proteases21 (USP21) (r = 0.738; P = 0.004) as potential targets associated with fasting blood glucose content. Given tight regulation of the ubiquitination status of proteins in muscle, we focused on USP21 and generated whole-body (KO) and skeletal muscle-specific USP21 knockout (MKO) mice. Transcriptomics, proteomics, and lipidomics assays in combination with various in vivo and in vitro experiments were performed to understand the functions of USP21 and underlying mechanisms. A high-fat diet (60%)-fed mouse model and diabetic patient-derived samples were utilized to assess the effects of USP21 on energy metabolism in skeletal muscle. RESULTS USP21 was highly expressed in both human and mouse skeletal muscle, and controlled skeletal muscle oxidative capacity and fuel consumption. USP21-KO or USP21-MKO significantly promoted oxidative fibre type changes (Δ36.6% or Δ47.2%), muscle mass increase (Δ13.8% to Δ22.8%), and energy expenditure through mitochondrial biogenesis, fatty acid oxidation, and UCP2/3 induction (P < 0.05 or P < 0.01). Consistently, cold exposure repressed USP21 expression in mouse skeletal muscle (Δ55.3%), whereas loss of USP21 increased thermogenesis (+1.37°C or +0.84°C; P < 0.01). Mechanistically, USP21 deubiquitinated DNA-PKcs and ACLY, which led to AMPK inhibition. Consequently, USP21 ablation diminished diet-induced obesity (WT vs. USP21-KO, Δ8.02 g, 17.1%, P < 0.01; litter vs. USP21-MKO, Δ3.48 g, 7.7%, P < 0.05) and insulin resistance. These findings were corroborated in a skeletal muscle-specific gene KO mouse model. USP21 was induced in skeletal muscle of a diabetic patient (1.94-fold), which was reciprocally changed to p-AMPK (0.30-fold). CONCLUSIONS The outcomes of this research provide novel information as to how USP21 in skeletal muscle contributes to systemic energy homeostasis, demonstrating USP21 as a key molecule in the regulation of myofibre type switch, muscle mass control, mitochondrial function, and heat generation and, thus, implicating the potential of this molecule and its downstream substrates network as targets for the treatment and/or prevention of muscle dysfunction and the associated metabolic diseases.
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Affiliation(s)
- Ayoung Kim
- College of Pharmacy, Seoul National University, Seoul, South Korea
| | - Ja Hyun Koo
- College of Pharmacy, Seoul National University, Seoul, South Korea.,Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Xing Jin
- College of Pharmacy, Seoul National University, Seoul, South Korea
| | - Wondong Kim
- Nephrology Division, Massachusetts General Hospital, Boston, MA, USA.,Department of Pharmacy, College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, South Korea
| | - Shi-Young Park
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University College of Medicine, Incheon, South Korea
| | - Sunghyouk Park
- College of Pharmacy, Seoul National University, Seoul, South Korea
| | - Eugene P Rhee
- Nephrology Division, Massachusetts General Hospital, Boston, MA, USA
| | - Cheol Soo Choi
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University College of Medicine, Incheon, South Korea.,Division of Endocrinology and Metabolism, Department of Internal Medicine, Gil Medical Center, Gachon University College of Medicine, Incheon, South Korea
| | - Sang Geon Kim
- College of Pharmacy and Integrated Research Institute for Drug Development, Dongguk University-Seoul, Goyang-si, Gyeonggi-Do, South Korea
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Sohn B, Park KY, Choi J, Koo JH, Han K, Joo B, Won SY, Cha J, Choi HS, Lee SK. Deep Learning-Based Software Improves Clinicians' Detection Sensitivity of Aneurysms on Brain TOF-MRA. AJNR Am J Neuroradiol 2021; 42:1769-1775. [PMID: 34385143 DOI: 10.3174/ajnr.a7242] [Citation(s) in RCA: 2] [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: 01/06/2021] [Accepted: 05/05/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The detection of cerebral aneurysms on MRA is a challenging task. Recent studies have used deep learning-based software for automated detection of aneurysms on MRA and have reported high performance. The purpose of this study was to evaluate the incremental value of using deep learning-based software for the detection of aneurysms on MRA by 2 radiologists, a neurosurgeon, and a neurologist. MATERIALS AND METHODS TOF-MRA examinations of intracranial aneurysms were retrospectively extracted. Four physicians interpreted the MRA blindly. After a washout period, they interpreted MRA again using the software. Sensitivity and specificity per patient, sensitivity per lesion, and the number of false-positives per case were measured. Diagnostic performances, including subgroup analysis of lesions, were compared. Logistic regression with a generalized estimating equation was used. RESULTS A total of 332 patients were evaluated; 135 patients had positive findings with 169 lesions. With software assistance, patient-based sensitivity was statistically improved after the washout period (73.5% versus 86.5%, P < .001). The neurosurgeon and neurologist showed a significant increase in patient-based sensitivity with software assistance (74.8% versus 85.2%, P = .03, and 56.3% versus 84.4%, P < .001, respectively), while the number of false-positive cases did not increase significantly (23 versus 30, P = .20, and 22 versus 24, P = .75, respectively). CONCLUSIONS Software-aided reading showed significant incremental value in the sensitivity of clinicians in the detection of aneurysms on MRA without a significant increase in false-positive findings, especially for the neurosurgeon and neurologist. Software-aided reading showed equivocal value for the radiologist.
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Affiliation(s)
- B Sohn
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
| | - K-Y Park
- Department of Neurosurgery (K.-Y.P.), Yonsei University College of Medicine, Seoul, South Korea
| | - J Choi
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
- Department of Neurology (J.C.), Yonsei University College of Medicine, Seoul, South Korea
- Department of Neurology (J.C.), Seoul Medical Center, Seoul, South Korea
| | - J H Koo
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
| | - K Han
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
| | - B Joo
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
| | - S Y Won
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
| | - J Cha
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
| | - H S Choi
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
- Department of Radiology (H.S.C.), Seoul Medical Center, Seoul, South Korea
| | - S-K Lee
- From the Department of Radiology (B.S., J.C., J.H.K., K.H., B.J., S.Y.W., J.C., H.S.C., S.-K.L.), Research Institute of Radiological Science and Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, South Korea
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Kim TH, Koo JH, Heo MJ, Han CY, Kim YI, Park SY, Cho IJ, Lee CH, Choi CS, Lee JW, Kim W, Cho JY, Kim SG. Overproduction of inter-α-trypsin inhibitor heavy chain 1 after loss of Gα 13 in liver exacerbates systemic insulin resistance in mice. Sci Transl Med 2020; 11:11/513/eaan4735. [PMID: 31597753 DOI: 10.1126/scitranslmed.aan4735] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 02/18/2018] [Accepted: 03/22/2019] [Indexed: 12/27/2022]
Abstract
The impact of liver disease on whole-body glucose homeostasis is largely attributed to dysregulated release of secretory proteins in response to metabolic stress. The molecular cues linking liver to whole-body glucose metabolism remain elusive. We found that expression of G protein α-13 (Gα13) was decreased in the liver of mice and humans with diabetes. Liver-specific deletion of the Gna13 gene in mice resulted in systemic glucose intolerance. Comparative secretome analysis identified inter-α-trypsin inhibitor heavy chain 1 (ITIH1) as a protein secreted by liver that was responsible for systemic insulin resistance in Gna13-deficient mice. Liver expression of ITIH1 positively correlated with surrogate markers for diabetes in patients with impaired glucose tolerance or overt diabetes. Mechanistically, a decrease in hepatic Gα13 caused ITIH1 oversecretion by liver through induction of O-GlcNAc transferase expression, facilitating ITIH1 deposition on the hyaluronan surrounding mouse adipose tissue and skeletal muscle. Neutralization of secreted ITIH1 ameliorated glucose intolerance in obese mice. Our findings demonstrate systemic insulin resistance in mice resulting from liver-secreted ITIH1 downstream of Gα13 and its reversal by ITIH1 neutralization.
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Affiliation(s)
- Tae Hyun Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Korea
| | - Mi Jeong Heo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Korea
| | - Chang Yeob Han
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Korea
| | - Yong-In Kim
- Department of Biochemistry, BK21 PLUS Program for Creative Veterinary Science Research and Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University , Seoul 08826, Korea
| | - Shi-Young Park
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University School of Medicine, Incheon 21999, Korea
| | - Il Je Cho
- College of Korean Medicine, Daegu Haany University, Gyeongsan, Gyeongsangbuk-do 38610, Korea
| | - Chang Ho Lee
- Department of Pharmacology, Institute of Biomedical Science, College of Medicine, Hanyang University, Seoul, Korea
| | - Cheol Soo Choi
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University School of Medicine, Incheon 21999, Korea.,Endocrinology, Internal Medicine, Gachon University Gil Medical Center, Incheon 21565, Korea
| | - Jung Weon Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Korea.,Interdisciplinary Program in Genetic Engineering, Seoul National University, Seoul 08826, Korea
| | - Won Kim
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, College of Medicine, Seoul National University, Seoul Metropolitan Government Boramae Medical Center, Seoul, Korea.
| | - Je-Yoel Cho
- Department of Biochemistry, BK21 PLUS Program for Creative Veterinary Science Research and Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University , Seoul 08826, Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Korea.
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Yoon HM, Jo Y, Shim WH, Lee JS, Ko TS, Koo JH, Yum MS. Disrupted Functional and Structural Connectivity in Angelman Syndrome. AJNR Am J Neuroradiol 2020; 41:889-897. [PMID: 32381544 DOI: 10.3174/ajnr.a6531] [Citation(s) in RCA: 5] [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] [Received: 10/23/2019] [Accepted: 03/16/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE This work investigated alterations in functional connectivity (FC) and associated structures in patients with Angelman syndrome (AS) by using integrated quantitative imaging analysis and connectivity measures. MATERIALS AND METHODS We obtained 3T brain MR imaging, including resting-state functional MR imaging, diffusion tensor imaging, and 3D T1-weighted imaging from children with AS (n = 14) and age- and sex-matched controls (n = 28). The brains of patients with AS were analyzed by measuring FC, white matter microstructural analysis, cortical thickness, and brain volumes; these were compared with brains of controls. RESULTS Interregional FC analysis revealed significantly reduced intra- and interhemispheric FC, especially in the basal ganglia and thalamus, in patients with AS. Significant reductions in fractional anisotropy were found in the corpus callosum, cingulum, posterior limb of the internal capsules, and arcuate fasciculus in patients with AS. Quantitative structural analysis also showed gray matter volume loss of the basal ganglia and diffuse WM volume reduction in AS compared with the control group. CONCLUSIONS This integrated quantitative MR imaging analysis demonstrated poor functional and structural connectivity, as well as brain volume reduction, in children with AS, which may explain the motor and language dysfunction observed in this well-characterized neurobehavioral phenotype.
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Affiliation(s)
- H M Yoon
- From the Department of Radiology and Research Institute of Radiology (H.M.Y., W.H.S., J.S.L., J.H.K.)
| | - Y Jo
- Asan Institute for Life Sciences (Y.J., W.H.S.), Asan Medical Center
| | - W H Shim
- From the Department of Radiology and Research Institute of Radiology (H.M.Y., W.H.S., J.S.L., J.H.K.)
- Asan Institute for Life Sciences (Y.J., W.H.S.), Asan Medical Center
| | - J S Lee
- From the Department of Radiology and Research Institute of Radiology (H.M.Y., W.H.S., J.S.L., J.H.K.)
| | - T S Ko
- Department of Pediatrics (T.S.K., M.S.Y.), Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - J H Koo
- From the Department of Radiology and Research Institute of Radiology (H.M.Y., W.H.S., J.S.L., J.H.K.)
| | - M S Yum
- Department of Pediatrics (T.S.K., M.S.Y.), Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea.
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11
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Koo JH, Plouffe SW, Meng Z, Lee DH, Yang D, Lim DS, Wang CY, Guan KL. Induction of AP-1 by YAP/TAZ contributes to cell proliferation and organ growth. Genes Dev 2019; 34:72-86. [PMID: 31831627 PMCID: PMC6938666 DOI: 10.1101/gad.331546.119] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [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: 08/07/2019] [Accepted: 11/12/2019] [Indexed: 12/21/2022]
Abstract
Yes-associated protein (YAP) and its homolog transcriptional coactivator with PDZ-binding motif (TAZ) are key effectors of the Hippo pathway to control cell growth and organ size, of which dysregulation yields to tumorigenesis or hypertrophy. Upon activation, YAP/TAZ translocate into the nucleus and bind to TEAD transcription factors to promote transcriptional programs for proliferation or cell specification. Immediate early genes, represented by AP-1 complex, are rapidly induced and control later-phase transcriptional program to play key roles in tumorigenesis and organ maintenance. Here, we report that YAP/TAZ directly promote FOS transcription that in turn contributes to the biological function of YAP/TAZ. YAP/TAZ bind to the promoter region of FOS to stimulate its transcription. Deletion of YAP/TAZ blocks the induction of immediate early genes in response to mitogenic stimuli. FOS induction contributes to expression of YAP/TAZ downstream target genes. Genetic deletion or chemical inhibition of AP-1 suppresses growth of YAP-driven cancer cells, such as Lats1/2-deficient cancer cells as well as Gαq/11 mutated uveal melanoma. Furthermore, AP-1 inhibition almost completely abrogates the hepatomegaly induced by YAP overexpression. Our findings reveal a feed-forward interplay between immediate early transcription of AP-1 and Hippo pathway function.
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Affiliation(s)
- Ja Hyun Koo
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Steven W Plouffe
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Zhipeng Meng
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Da-Hye Lee
- National Creative Research Initiatives Center for Cell Division and Differentiation, Department of Biological Science, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Di Yang
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Dae-Sik Lim
- National Creative Research Initiatives Center for Cell Division and Differentiation, Department of Biological Science, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Cun-Yu Wang
- Division of Oral Biology and Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Kun-Liang Guan
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
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12
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Wu HM, Kim TH, Kim A, Koo JH, Joo MS, Kim SG. Liver X Receptor α-Induced Cannabinoid Receptor 2 Inhibits Ubiquitin-Specific Peptidase 4 Through miR-27b, Protecting Hepatocytes From TGF-β. Hepatol Commun 2019; 3:1373-1387. [PMID: 31592043 PMCID: PMC6771303 DOI: 10.1002/hep4.1415] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 07/13/2019] [Indexed: 01/16/2023] Open
Abstract
Liver X receptor‐alpha (LXRα) acts as a double‐edged sword in different biological situations. Given the elusive role of LXRα in hepatocyte viability, this study investigated whether LXRα protects hepatocytes from injurious stimuli and the underlying basis. LXRα activation prevented hepatocyte apoptosis from CCl4 challenges in mice. Consistently, LXRα protected hepatocytes specifically from transforming growth factor‐beta (TGF‐β), whereas LXRα deficiency aggravated TGF‐β‐induced hepatocyte injury. In the Gene Expression Omnibus database analysis for LXR−/− mice, TGF‐β receptors were placed in the core network. Hierarchical clustering and correlation analyses enabled us to find cannabinoid receptor 2 (CB2) as a gene relevant to LXRα. In human fibrotic liver samples, both LXRα and CB2 were lower in patients with septal fibrosis and cirrhosis than those with portal fibrosis. LXRα transcriptionally induced CB2; CB2 then defended hepatocytes from TGF‐β. In a macrophage depletion model, JWH133 (a CB2 agonist) treatment prevented toxicant‐induced liver injury. MicroRNA 27b (miR‐27b) was identified as an inhibitor of ubiquitin‐specific peptidase 4 (USP4), deubiquitylating TGF‐β receptor 1 (TβRI), downstream from CB2. Liver‐specific overexpression of LXRα protected hepatocytes from injurious stimuli and attenuated hepatic inflammation and fibrosis. Conclusion: LXRα exerts a cytoprotective effect against TGF‐β by transcriptionally regulating the CB2 gene in hepatocytes, and CB2 then inhibits USP4‐stabilizing TβRI through miR‐27b. Our data provide targets for the treatment of acute liver injury.
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Affiliation(s)
- Hong Min Wu
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul Korea
| | - Tae Hyun Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul Korea
| | - Ayoung Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul Korea
| | - Min Sung Joo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National University Seoul Korea
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13
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Joo MS, Shin SB, Kim EJ, Koo JH, Yim H, Kim SG. Nrf2-lncRNA controls cell fate by modulating p53-dependent Nrf2 activation as an miRNA sponge for Plk2 and p21 cip1. FASEB J 2019; 33:7953-7969. [PMID: 30897343 DOI: 10.1096/fj.201802744r] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [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: 01/15/2023]
Abstract
Long noncoding RNA (lncRNA) capable of controlling antioxidative capacity remains to be investigated. Nuclear factor erythroid-2-related factor 2 (Nrf2) is a central molecule for cellular defense that increases antioxidative capacity. We identified a novel lncRNA named Nrf2-activating lncRNA (Nrf2-lncRNA) transcribed from an upstream region of the microRNA 122 gene (MIR122). Nrf2-lncRNA existed in the cytoplasm, suggestive of its function as a competing endogenous RNA [ceRNA, microRNA (miRNA) sponge]. Nrf2-lncRNA served as a ceRNA for polo-like kinase (Plk) 2 and cyclin-dependent kinase inhibitor 1 (p21cip1) through binding of miRNA 128 and miRNA 224, inducing Plk2/Nrf2/p21cip1 complexation for Nrf2 activation in the cells under p53-activating conditions (i.e., DNA damage and serum deprivation). Nrf2-lncRNA expression was suppressed with the initiation of apoptosis, being a rheostat for cell fate determination. Nrf2-lncRNA levels correlated with the recurrence-free postsurgery survival rate of patients with hepatocellular carcinoma. Collectively, Nrf2-lncRNA promotes Plk2 and p21cip1 translation by competing for specific miRNAs and activating Nrf2 under surviving conditions from oxidative stress, implying that Nrf2-lncRNA serves as a fine-tuning rheostat for cell fate decision.-Joo, M. S., Shin, S.-B., Kim, E. J., Koo, J. H., Yim, H., Kim, S. G. Nrf2-lncRNA controls cell fate by modulating p53-dependent Nrf2 activation as an miRNA sponge for Plk2 and p21cip1.
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Affiliation(s)
- Min Sung Joo
- College of Pharmacy, Seoul National University, Seoul, South Korea.,Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Sol-Bi Shin
- College of Pharmacy, Hanyang University, Ansan, South Korea; and.,Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, South Korea
| | - Eun Jung Kim
- College of Pharmacy, Seoul National University, Seoul, South Korea.,Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Ja Hyun Koo
- College of Pharmacy, Seoul National University, Seoul, South Korea.,Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Hyungshin Yim
- College of Pharmacy, Hanyang University, Ansan, South Korea; and.,Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, South Korea
| | - Sang Geon Kim
- College of Pharmacy, Seoul National University, Seoul, South Korea.,Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
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14
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Joo MS, Koo JH, Kim TH, Kim YS, Kim SG. LRH1-driven transcription factor circuitry for hepatocyte identity: Super-enhancer cistromic analysis. EBioMedicine 2019; 40:488-503. [PMID: 30638865 PMCID: PMC6413675 DOI: 10.1016/j.ebiom.2018.12.056] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 12/19/2018] [Accepted: 12/26/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The injured liver loses normal function, with concomitant decrease of key identity genes. Super-enhancers contribute to mammalian cell identity. Here, we identified core transcription factors (TFs) that are active in hepatocytes, using genome-wide analysis and hierarchical ordering of super-enhancer distribution. METHODS Expression of core TFs was assessed in a cohort of patients with hepatitis or cirrhosis and animal models. Quantitative PCR, chromatin immunoprecipitation assays, and hydrodynamic gene delivery methods were used to assess gene regulation and hepatocyte viability. RNA-sequencing data were generated to investigate the role of LRH1 in hepatocyte protection from injury. RESULTS Network analysis of super-enhancer-associated gene interactions and expression arrays for cohorts of patients with hepatitis and cirrhosis enabled us to identify a super-enhancer-associated network, and LRH1, HNF4α, PPARα, and RXRα as core TFs. In mouse models, expression of core TFs was robustly inhibited by single and multiple challenge(s) with liver toxicant. RNA-seq analysis revealed changes in expression in the super-enhancer-associated genes sensitively biased toward repression by intoxication. LRH1 gene delivery prevented the loss of hepatic super-enhancer-associated signaling circuitry in toxicant-challenged mice, and protected the liver from injury, indicating the role of LRH1 in hepatocyte identity and viability. In hepatocytes, overexpression of each core TF promoted induction of other TFs. CONCLUSION Overall, this study identified LRH1-driven pathway as a circuitry responsible for hepatocyte identity by using cistromic analysis, improving our understanding of liver pathophysiology and identifying novel therapeutic targets.
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Affiliation(s)
- Min Sung Joo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Tae Hyun Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Yun Seok Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea.
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15
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Kim TH, Yang YM, Han CY, Koo JH, Oh H, Kim SS, You BH, Choi YH, Park TS, Lee CH, Kurose H, Noureddin M, Seki E, Wan YJY, Choi CS, Kim SG. Gα12 ablation exacerbates liver steatosis and obesity by suppressing USP22/SIRT1-regulated mitochondrial respiration. J Clin Invest 2018; 128:5587-5602. [PMID: 30300140 DOI: 10.1172/jci97831] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [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: 10/02/2017] [Accepted: 10/02/2018] [Indexed: 12/20/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) arises from mitochondrial dysfunction under sustained imbalance between energy intake and expenditure, but the underlying mechanisms controlling mitochondrial respiration have not been entirely understood. Heterotrimeric G proteins converge with activated GPCRs to modulate cell-signaling pathways to maintain metabolic homeostasis. Here, we investigated the regulatory role of G protein α12 (Gα12) on hepatic lipid metabolism and whole-body energy expenditure in mice. Fasting increased Gα12 levels in mouse liver. Gα12 ablation markedly augmented fasting-induced hepatic fat accumulation. cDNA microarray analysis from Gna12-KO liver revealed that the Gα12-signaling pathway regulated sirtuin 1 (SIRT1) and PPARα, which are responsible for mitochondrial respiration. Defective induction of SIRT1 upon fasting was observed in the liver of Gna12-KO mice, which was reversed by lentivirus-mediated Gα12 overexpression in hepatocytes. Mechanistically, Gα12 stabilized SIRT1 protein through transcriptional induction of ubiquitin-specific peptidase 22 (USP22) via HIF-1α increase. Gα12 levels were markedly diminished in liver biopsies from NAFLD patients. Consistently, Gna12-KO mice fed a high-fat diet displayed greater susceptibility to diet-induced liver steatosis and obesity due to decrease in energy expenditure. Our results demonstrate that Gα12 regulates SIRT1-dependent mitochondrial respiration through HIF-1α-dependent USP22 induction, identifying Gα12 as an upstream molecule that contributes to the regulation of mitochondrial energy expenditure.
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Affiliation(s)
- Tae Hyun Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Yoon Mee Yang
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea.,Division of Digestive and Liver Diseases, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Chang Yeob Han
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea.,Department of Pharmacology, School of Medicine, Wonkwang University, Iksan, Jeonbuk, South Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Hyunhee Oh
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Incheon, South Korea
| | - Su Sung Kim
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Incheon, South Korea
| | - Byoung Hoon You
- College of Pharmacy, Dongguk University, Ilsan Dong-Gu, Goyang, Gyeoggi-Do, South Korea
| | - Young Hee Choi
- College of Pharmacy, Dongguk University, Ilsan Dong-Gu, Goyang, Gyeoggi-Do, South Korea
| | - Tae-Sik Park
- Department of Life Science, Gachon University, Seongnam, Gyeonggi-Do, South Korea
| | - Chang Ho Lee
- College of Medicine, Hanyang University, Seoul, South Korea
| | - Hitoshi Kurose
- Department of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Mazen Noureddin
- Fatty Liver Disease Program, Division of Digestive and Liver Diseases, Department of Medicine, Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Ekihiro Seki
- Division of Digestive and Liver Diseases, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Yu-Jui Yvonne Wan
- Department of Medical Pathology and Laboratory Medicine, UCD, Sacramento, California, USA
| | - Cheol Soo Choi
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Incheon, South Korea.,Endocrinology, Internal Medicine, Gachon University Gil Medical Center, Incheon, South Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
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16
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Abstract
Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) are two homologous transcriptional coactivators that promote cell proliferation, stem cell maintenance, and tissue homeostasis. Under favorable conditions, YAP and TAZ are active to promote cell growth through a transcriptional program mediated by the TEAD family transcription factors. Given the indispensability of cellular energy and metabolites for survival and growth, YAP and TAZ are inhibited when energy level is low. Indeed, glucose, fatty acids, hormones, and other metabolic factors have been recently revealed to regulate YAP and TAZ. Conversely, YAP and TAZ are also involved in metabolism regulation, such as to promote glycolysis, lipogenesis, and glutaminolysis, suggesting YAP and TAZ as emerging nodes in coordinating nutrient availability with cell growth and tissue homeostasis. In this Review, we summarize recent findings and provide a current overview of YAP and TAZ in metabolism by focusing on the role of YAP and TAZ as integrators for metabolic cues and cell growth.
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Affiliation(s)
- Ja Hyun Koo
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kun-Liang Guan
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA.
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17
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Kim SG, Koo JH. Loss of Gα13 exercise‐mimetically reprograms skeletal muscle through Rock2. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.670.1] [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)
- Sang Geon Kim
- College of PharmacySeoul National UniversitySeoulRepublic of Korea
| | - Ja Hyun Koo
- College of PharmacySeoul National UniversitySeoulRepublic of Korea
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18
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Kim KM, Han CY, Kim JY, Cho SS, Kim YS, Koo JH, Lee JM, Lim SC, Kang KW, Kim JS, Hwang SJ, Ki SH, Kim SG. Gα 12 overexpression induced by miR-16 dysregulation contributes to liver fibrosis by promoting autophagy in hepatic stellate cells. J Hepatol 2018; 68:493-504. [PMID: 29080810 PMCID: PMC5818314 DOI: 10.1016/j.jhep.2017.10.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 10/10/2017] [Accepted: 10/11/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Hepatic stellate cells (HSCs) have a role in liver fibrosis. Guanine nucleotide-binding α-subunit 12 (Gα12) converges signals from G-protein-coupled receptors whose ligand levels are elevated in the environment during liver fibrosis; however, information is lacking on the effect of Gα12 on HSC trans-differentiation. This study investigated the expression of Gα12 in HSCs and the molecular basis of the effects of its expression on liver fibrosis. METHODS Gα12 expression was assessed by immunostaining, and immunoblot analyses of mouse fibrotic liver tissues and primary HSCs. The role of Gα12 in liver fibrosis was estimated using a toxicant injury mouse model with Gα12 gene knockout and/or HSC-specific Gα12 delivery using lentiviral vectors, in addition to primary HSCs and LX-2 cells using microRNA (miR) inhibitors, overexpression vectors, or adenoviruses. miR-16, Gα12, and LC3 were also examined in samples from patients with fibrosis. RESULTS Gα12 was overexpressed in activated HSCs and fibrotic liver, and was colocalised with desmin. In a carbon tetrachloride-induced fibrosis mouse model, Gα12 ablation prevented increases in fibrosis and liver injury. This effect was attenuated by HSC-specific lentiviral delivery of Gα12. Moreover, Gα12 activation promoted autophagy accompanying c-Jun N-terminal kinase-dependent ATG12-5 conjugation. In addition, miR-16 was found to be a direct inhibitor of the de novo synthesis of Gα12. Modulations of miR-16 altered autophagy in HSCs. In a fibrosis animal model or patients with severe fibrosis, miR-16 levels were lower than in their corresponding controls. Consistently, cirrhotic patient liver tissues showed Gα12 and LC3 upregulation in desmin-positive areas. CONCLUSIONS miR-16 dysregulation in HSCs results in Gα12 overexpression, which activates HSCs by facilitating autophagy through ATG12-5 formation. This suggests that Gα12 and its regulatory molecules could serve as targets for the amelioration of liver fibrosis. LAY SUMMARY Guanine nucleotide-binding α-subunit 12 (Gα12) is upregulated in activated hepatic stellate cells (HSCs) as a consequence of the dysregulation of a specific microRNA that is abundant in HSCs, facilitating the progression of liver fibrosis. This event is mediated by c-Jun N-terminal kinase-dependent ATG12-5 formation and the promotion of autophagy. We suggest that Gα12 and its associated regulators could serve as new targets in HSCs for the treatment of liver fibrosis.
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Affiliation(s)
- Kyu Min Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Chang Yeob Han
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Ji Young Kim
- College of Pharmacy, Chosun University, Gwangju 61452, Republic of Korea
| | - Sam Seok Cho
- College of Pharmacy, Chosun University, Gwangju 61452, Republic of Korea
| | - Yun Seok Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Jung Min Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Sung Chul Lim
- College of Medicine, Chosun University, Gwangju 61452, Republic of Korea
| | - Keon Wook Kang
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Jae-Sung Kim
- Departments of Surgery University of Florida, Gainesville, FL 32611, USA
| | - Se Jin Hwang
- College of Medicine, Hanyang University, Seoul 04763, Republic of Korea
| | - Sung Hwan Ki
- College of Pharmacy, Chosun University, Gwangju 61452, Republic of Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea.
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19
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Song MK, Park C, Lee YD, Kim H, Kim MK, Kwon JO, Koo JH, Joo MS, Kim SG, Kim HH. Gα12 regulates osteoclastogenesis by modulating NFATc1 expression. J Cell Mol Med 2017; 22:849-860. [PMID: 29077264 PMCID: PMC5783869 DOI: 10.1111/jcmm.13370] [Citation(s) in RCA: 10] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2017] [Accepted: 08/09/2017] [Indexed: 11/28/2022] Open
Abstract
The G12 family of G protein alpha subunits has been shown to participate in the regulation of various physiological processes. However, the role of Gα12 in bone physiology has not been well described. Here, by micro‐CT analysis, we discovered that Gα12‐knockout mice have an osteopetrotic phenotype. Histological examination showed lower osteoclast number in femoral tissue of Gα12‐knockout mice compared to wild‐type mice. Additionally, in vitro osteoclastic differentiation of precursor cells with receptor activator of nuclear factor‐κB ligand (RANKL) showed that Gα12 deficiency decreased the number of osteoclast generated and the bone resorption activity. The induction of nuclear factor of activated T‐cell c1 (NFATc1), the key transcription factor of osteoclastogenesis, and the activation of RhoA by RANKL was also significantly suppressed by Gα12 deficiency. We further found that the RANKL induction of NFATc1 was not dependent on RhoA signalling, while osteoclast precursor migration and bone resorption required RhoA in the Gα12‐mediated regulation of osteoclasts. Therefore, Gα12 plays a role in differentiation through NFATc1 and in cell migration and resorption activity through RhoA during osteoclastogenesis.
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Affiliation(s)
- Min-Kyoung Song
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Cheolkyu Park
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Yong Deok Lee
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Haemin Kim
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Min Kyung Kim
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Jun-Oh Kwon
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Min Sung Joo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Hong-Hee Kim
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
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20
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Koo JH, Kim TH, Park SY, Joo MS, Han CY, Choi CS, Kim SG. Gα13 ablation reprograms myofibers to oxidative phenotype and enhances whole-body metabolism. J Clin Invest 2017; 127:3845-3860. [PMID: 28920922 DOI: 10.1172/jci92067] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 08/02/2017] [Indexed: 12/24/2022] Open
Abstract
Skeletal muscle is a key organ in energy homeostasis owing to its high requirement for nutrients. Heterotrimeric G proteins converge signals from cell-surface receptors to potentiate or blunt responses against environmental changes. Here, we show that muscle-specific ablation of Gα13 in mice promotes reprogramming of myofibers to the oxidative type, with resultant increases in mitochondrial biogenesis and cellular respiration. Mechanistically, Gα13 and its downstream effector RhoA suppressed nuclear factor of activated T cells 1 (NFATc1), a chief regulator of myofiber conversion, by increasing Rho-associated kinase 2-mediated (Rock2-mediated) phosphorylation at Ser243. Ser243 phosphorylation of NFATc1 was reduced after exercise, but was higher in obese animals. Consequently, Gα13 ablation in muscles enhanced whole-body energy metabolism and increased insulin sensitivity, thus affording protection from diet-induced obesity and hepatic steatosis. Our results define Gα13 as a switch regulator of myofiber reprogramming, implying that modulations of Gα13 and its downstream effectors in skeletal muscle are a potential therapeutic approach to treating metabolic diseases.
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Affiliation(s)
- Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Tae Hyun Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Shi-Young Park
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University School of Medicine, Incheon, South Korea
| | - Min Sung Joo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Chang Yeob Han
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
| | - Cheol Soo Choi
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University School of Medicine, Incheon, South Korea.,Endocrinology, Internal Medicine, Gachon University Gil Medical Center, Incheon, South Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, South Korea
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Abstract
Protein phosphorylation at specific sites determines its conformation and interaction with other molecules. Thus, protein phosphorylation affects biological functions and characteristics of the cell. Currently, the most common method for discovering phosphorylation sites is by liquid chromatography/mass spectrometry (LC/MS) analysis, a rapid and sensitive method. However, relatively labile phosphate moieties are often released from phosphopeptides during the fragmentation step, which often yields false-negative signals. In such cases, a traditional in vitro kinase assay using site-directed mutants would be more accurate, but this method is laborious and time-consuming. Therefore, an alternative method using peptide competition may be advantageous. The consensus recognition motif of 5' adenosine monophosphate-activated protein kinase (AMPK) has been established1 and was validated using a positional scanning peptide library assay2. Thus, AMPK phosphorylation sites for a novel substrate could be predicted and confirmed by the peptide competition assays. In this report, we describe the detailed steps and procedures for the in vitro oligopeptide-competing kinase assay by illustrating AMPK-mediated nuclear factor erythroid 2-related factor 2 (Nrf2) phosphorylation. To authenticate the phosphorylation site, we carried out a sequential in vitro kinase assay using a site-specific mutant. Overall, the peptide competition assay provides a method to screen multiple potential phosphorylation sites and to identify sites for validation by the phosphorylation site mutants.
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Affiliation(s)
- Min Sung Joo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University
| | - Sol-Bi Shin
- College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University
| | - Hyungshin Yim
- College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University;
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Han CY, Kim TH, Koo JH, Kim SG. Farnesoid X receptor as a regulator of fuel consumption and mitochondrial function. Arch Pharm Res 2016; 39:1062-74. [PMID: 27515052 DOI: 10.1007/s12272-016-0812-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Accepted: 08/04/2016] [Indexed: 12/24/2022]
Abstract
Maintenance of energy homeostasis is crucial for survival of organism. There exists a close link between energy metabolism and cell survival, which are coordinately regulated by common signaling pathways. Farnesoid X receptor (FXR) serves as a ligand-mediated transcription factor to regulate diverse genes involved in bile acid, lipid, and glucose metabolism, controlling cellular and systemic energy metabolism. Another important aspect on FXR biology is related to its beneficial effect on cell survival. FXR exerts antioxidative and cytoprotective effect, which is closely associated with the ability of FXR to regulate mitochondrial function. To maintain complex biological processes under homeostasis, FXR activity needs to be dynamically and tightly controlled by different signaling pathways and modifications. In this review, we discuss the role of FXR in the regulation of energy metabolism and cell survival, with the goal of understanding molecular basis for FXR regulation in physiological and pathological conditions. This information may be of assistance in understanding recent advancements of FXR research and strategies for the prevention and treatment of metabolic disorders.
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Affiliation(s)
- Chang Yeob Han
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Tae Hyun Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea.
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Han CY, Lim SW, Koo JH, Kim W, Kim SG. PHLDA3 overexpression in hepatocytes by endoplasmic reticulum stress via IRE1-Xbp1s pathway expedites liver injury. Gut 2016; 65:1377-88. [PMID: 25966993 PMCID: PMC4975835 DOI: 10.1136/gutjnl-2014-308506] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 04/20/2015] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Endoplasmic reticulum (ER) stress is involved in liver injury, but molecular determinants are largely unknown. This study investigated the role of pleckstrin homology-like domain, family A, member-3 (PHLDA3), in hepatocyte death caused by ER stress and the regulatory basis. DESIGN Hepatic PHLDA3 expression was assessed in HCV patients with hepatitis and in several animal models with ER stress. Immunoblottings, PCR, reporter gene, chromatin immunoprecipitation (ChIP) and mutation analyses were done to explore gene regulation. The functional effect of PHLDA3 on liver injury was validated using lentiviral delivery of shRNA. RESULTS PHLDA3 was overexpressed in relation to hepatocyte injury in patients with acute liver failure or liver cirrhosis or in toxicant-treated mice. In HCV patients with liver injury, PHLDA3 was upregulated in parallel with the induction of ER stress marker. Treatment of mice with tunicamycin (Tm) (an ER stress inducer) increased PHLDA3 expression in the liver. X box-binding protein-1 (Xbp1) was newly identified as a transcription factor responsible for PHLDA3 expression. Inositol-requiring enzyme 1 (IRE1) (an upstream regulator of Xbp1) was required for PHLDA3 induction by Tm, whereas other pathways (c-Jun N-terminal kinase (JNK), protein kinase RNA-like endoplasmic reticulum kinase (PERK) and activating transcription factor 6 (ATF6)) were not. PHLDA3 overexpression correlated with the severity of hepatocyte injury in animal or cell model of ER stress. In p53-deficient cells, ER stress inducers transactivated PHLDA3 with a decrease in cell viability. ER stress-induced hepatocyte death depended on serine/threonine protein kinase B (Akt) inhibition by PHLDA3. Lentiviral delivery of PHLDA3 shRNA to mice abrogated p-Akt inhibition in the liver by Tm, attenuating hepatocyte injury. CONCLUSIONS ER stress in hepatocytes induces PHLDA3 via IRE1-Xbp1s pathway, which facilitates liver injury by inhibiting Akt.
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Affiliation(s)
- Chang Yeob Han
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Sang Woo Lim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Won Kim
- Department of Internal Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
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Yang YM, Lee CG, Koo JH, Kim TH, Lee JM, An J, Kim KM, Kim SG. Gα12 overexpressed in hepatocellular carcinoma reduces microRNA-122 expression via HNF4α inactivation, which causes c-Met induction. Oncotarget 2016; 6:19055-69. [PMID: 25965999 PMCID: PMC4662475 DOI: 10.18632/oncotarget.3957] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/08/2015] [Indexed: 12/12/2022] Open
Abstract
MicroRNA-122 (miR-122) is implicated as a regulator of physiological and pathophysiological processes in the liver. Overexpression of Gα12 is associated with overall survival in patients with hepatocellular carcinoma (HCC). Array-based miRNA profiling was performed on Huh7 stably transfected with activated Gα12 to find miRNAs regulated by the Gα12 pathway; among them, miR-122 was most greatly repressed. miR-122 directly inhibits c-Met expression, playing a role in HCC progression. Gα12 destabilized HNF4α by accelerating ubiquitination, impeding constitutive expression of miR-122. miR-122 mimic transfection diminished the ability of Gα12 to increase c-Met and to activate ERK, STAT3, and Akt/mTOR, suppressing cell proliferation with augmented apoptosis. Consistently, miR-122 transfection prohibited tumor cell colony formation and endothelial tube formation. In a xenograft model, Gα12 knockdown attenuated c-Met expression by restoring HNF4α levels, and elicited tumor cell apoptosis but diminished Ki67 intensities. In human HCC samples, Gα12 levels correlated to c-Met and were inversely associated with miR-122. Both miR-122 and c-Met expression significantly changed in tumor node metastasis (TNM) stage II/III tumors. Moreover, changes in Gα12 and miR-122 levels discriminated recurrence-free and overall survival rates of HCC patients. Collectively, Gα12 overexpression in HCC inhibits MIR122 transactivation by inactivating HNF4α, which causes c-Met induction, contributing to cancer aggressiveness.
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Affiliation(s)
- Yoon Mee Yang
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Chan Gyu Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Tae Hyun Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Jung Min Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Jihyun An
- Department of Internal Medicine, Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Kang Mo Kim
- Department of Internal Medicine, Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
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Koo JH, Lee HJ, Kim W, Kim SG. Endoplasmic Reticulum Stress in Hepatic Stellate Cells Promotes Liver Fibrosis via PERK-Mediated Degradation of HNRNPA1 and Up-regulation of SMAD2. Gastroenterology 2016; 150:181-193.e8. [PMID: 26435271 DOI: 10.1053/j.gastro.2015.09.039] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 09/22/2015] [Accepted: 09/25/2015] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Endoplasmic reticulum (ER) stress has been implicated in a variety of diseases. Hepatic stellate cells (HSCs) contribute to the development of liver fibrosis. Information on the link between ER stress and HSC activation is scarce. We investigated the effects of ER stress in HSCs on the progression of liver fibrosis and the regulation of this process in cells and mice. METHODS Proteins and messenger RNAs were measured in 2 sets of liver samples (n = 25 and n = 44) collected from patients with chronic hepatitis C virus infection and/or fibrosis. ER stress was induced in cells and mice using chemical agents. Lentiviral vectors were constructed to express glucose-regulated protein 78 (GRP78; also known as HSPA5) or heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) from the α-smooth muscle actin promoter and injected into C57BL/6 mice for HSC-specific gene expression. Liver tissues and HSCs were collected from mice or rats and analyzed using immunoblottings and quantitative reverse-transcription polymerase chain reaction. LX-2 cells were transfected with small interfering RNAs, microRNA mimics, or overexpression vectors. RESULTS Hepatic ER stress was much higher in liver tissues from patients with severe vs mild fibrosis. ER stress induced fibrogenic genes in HSCs. Targeted lentiviral delivery of glucose-regulated protein 78 to HSCs in mice reduced fiber accumulation in liver. Levels of SMAD2, but not SMAD3, were increased in fibrotic liver tissues from patients or mice exposed to ER stress; small interfering RNA-mediated knockdown of SMAD2 reduced ER stress-mediated activation of HSCs. In rat HSCs, ER stress increased levels of SMAD2 messenger RNA by decreasing levels of microRNA 18a (MIR18A), an inhibitor of SMAD2 expression, rather than transactivating the SMAD2 gene. ER stress-activated PKR-like endoplasmic reticulum kinase, also known as EIF2AK3 (PERK) phosphorylated HNRNPA1, a protein required for the maturational processing of primary MIR18A, at Thr51, accelerating its degradation. Overexpression of HNRNPA1 (or its T51A mutant) in HSCs of mice inhibited liver fibrosis. Severe fibrotic liver tissues from patients had increased levels of phosphorylated PERK and reduced levels of HNRNPA1 in HSCs, compared with mild fibrotic liver tissues. CONCLUSIONS ER stress in HSCs promotes liver fibrosis by inducing overexpression of SMAD2, via dysregulation of MIR18A; this dysregulation is mediated by PERK phosphorylation and destabilization of HNRNPA1.
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Affiliation(s)
- Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Hyo Ju Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
| | - Won Kim
- Department of Internal Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Korea
| | - Sang Geon Kim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea.
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Abstract
During the past decades, phytochemical terpenoids, polyphenols, lignans, flavonoids, and alkaloids have been identified as antioxidative and cytoprotective agents. Adenosine monophosphate-activated protein kinase (AMPK) is a kinase that controls redox-state and oxidative stress in the cell, and serves as a key molecule regulating energy metabolism. Many phytochemicals directly or indirectly alter the AMPK pathway in distinct manners, exerting catabolic metabolism. Some of them are considered promising in the treatment of metabolic diseases such as type II diabetes, obesity, and hyperlipidemia. Another important kinase that regulates energy metabolism is Fyn kinase, a member of the Src family kinases that plays a role in various cellular responses such as insulin signaling, cell growth, oxidative stress and apoptosis. Phytochemical inhibition of Fyn leads to AMPK-mediated protection of the cell in association with increased antioxidative capacity and mitochondrial biogenesis. The kinases may work together to form a signaling circuitry for the homeostasis of energy conservation and expenditure, and may serve as targets of phytochemicals. This review is intended as a compilation of recent advancements in the pharmacological research of phytochemicals targeting Fyn and AMPK circuitry, providing information for the prevention and treatment of metabolic diseases and the accompanying tissue injuries.
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Affiliation(s)
- Chan Gyu Lee
- College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Korea.
| | - Ja Hyun Koo
- College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Korea.
| | - Sang Geon Kim
- College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Korea.
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Heo MJ, Kim YM, Koo JH, Yang YM, An J, Lee SK, Lee SJ, Kim KM, Park JW, Kim SG. microRNA-148a dysregulation discriminates poor prognosis of hepatocellular carcinoma in association with USP4 overexpression. Oncotarget 2015; 5:2792-806. [PMID: 24798342 PMCID: PMC4058045 DOI: 10.18632/oncotarget.1920] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [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] [Indexed: 12/17/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is classified as a poor prognostic tumor, and becomes frequently aggressive. MicroRNAs emerge as key contributors to tumor progression. This study investigated whether miR-148a dysregulation differentiates poor prognosis of HCC, exploring new targets of miR-148a. miR-148a dysregulation discriminated not only the overall survival and recurrence free survival rates of HCC, but the microvascular invasion. In the human HCC samples, ubiquitin specific protease 4 (USP4) and sphingosine 1-phosphate receptor 1 (S1P1) were up-regulated as the new targets of miR-148a. USP4 and S1P1 were up-regulated in mesenchymal-type liver-tumor cells with miR-148a dysregulation, facilitating migration and proliferation of tumor cells. The inverse relationship between miR-148a and the identified targets was verified in a tumor xenograft model. In the analysis of human samples, the expression of USP4, but not S1P1, correlated with the decrease of miR-148a. In a heterotropic patient-derived HCC xenograft model, USP4 was also overexpressed in G1 and G2 tumors when miR-148a was dysregulated, reflecting the closer link between miR-148a and USP4 for a shift in the expansion phase of tumorgraft. In conclusion, miR-148a dysregulation affects the poor prognosis of HCC. Of the identified targets of miR-148a, USP4 overexpression may contribute to HCC progression towards more aggressive feature.
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Affiliation(s)
- Mi Jeong Heo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
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Jung HS, Seo YR, Yang YM, Koo JH, An J, Lee SJ, Kim KM, Kim SG. Gα12 gep oncogene inhibits FOXO1 in hepatocellular carcinoma as a consequence of miR-135b and miR-194 dysregulation. Cell Signal 2014; 26:1456-65. [DOI: 10.1016/j.cellsig.2014.02.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 02/26/2014] [Indexed: 12/20/2022]
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Joo MS, Lee CG, Koo JH, Kim SG. miR‐125b transcriptionally induced by Nrf2 inhibits AhR repressor for AhR activation (663.12). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.663.12] [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)
- Min Sung Joo
- College of PharmacySEOUL National UniversitySEOULRepublic of Korea
| | - Chan Gyu Lee
- College of PharmacySEOUL National UniversitySEOULRepublic of Korea
| | - Ja Hyun Koo
- College of PharmacySEOUL National UniversitySEOULRepublic of Korea
| | - Sang Geon Kim
- College of PharmacySEOUL National UniversitySEOULRepublic of Korea
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Heo MJ, Kim YM, Koo JH, Kim SG. S1P receptor‐1 and USP4 induced by microRNA‐148a deregulation facilitate liver cancer progression (766.1). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.766.1] [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)
- Mi Jeong Heo
- Collge of PharmacySEOUL National UniversitySEOULRepublic of Korea
| | - Young Mi Kim
- Collge of PharmacySEOUL National UniversitySEOULRepublic of Korea
| | - Ja Hyun Koo
- Collge of PharmacySEOUL National UniversitySEOULRepublic of Korea
| | - Sang Geon Kim
- Collge of PharmacySEOUL National UniversitySEOULRepublic of Korea
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Joo MS, Lee CG, Koo JH, Kim SG. miR-125b transcriptionally increased by Nrf2 inhibits AhR repressor, which protects kidney from cisplatin-induced injury. Cell Death Dis 2013; 4:e899. [PMID: 24176857 PMCID: PMC3920955 DOI: 10.1038/cddis.2013.427] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [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: 08/22/2013] [Revised: 09/25/2013] [Accepted: 09/26/2013] [Indexed: 01/04/2023]
Abstract
MicroRNAs (miRNAs) have a role in the cellular defense mechanism. Nuclear factor erythroid-2-related factor 2 (Nrf2) increases antioxidant enzyme capacity. However, miRNA transcriptionally controlled by Nrf2 had been uncharacterized. Here we report that miR-125b is transactivated by Nrf2 and inhibits aryl hydrocarbon receptor (AhR) repressor (AhRR). Bioinformatic approaches enabled us to extract six candidate miRNAs. Of them, only miR-125b was increased in the kidney of mice treated with oltipraz. Nrf2 overexpression enhanced primary, precursor and mature miR-125b levels. Functional assays revealed MIR125B1 is a bona fide target gene of Nrf2. Oltipraz treatment protected the kidney from cisplatin toxicity with increase of miR-125b. Consistently, Nrf2 knockout abrogated an adaptive increase of miR-125b elicited by cisplatin, augmenting kidney injury. An integrative network of miRNA and messenger RNA changes enabled us to predict miR-125b as an inhibitor of AhRR for the control of AhR activity and cell survival. In our molecular study, miR-125b inhibited AhRR and thereby activated AhR, leading to the induction of mdm2. Consistently, p53 activation by cisplatin was diminished by either miR-125b or oltipraz treatment. The results of experiments using miR-125b mimic or small interfering RNA of AhRR verified the role of miR-125b in AhRR regulation for kidney protection. In conclusion, miR-125b is transcriptionally activated by Nrf2 and serves as an inhibitor of AhRR, which contributes to protecting kidney from acute injury.
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Affiliation(s)
- M S Joo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
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Affiliation(s)
- F Tran
- Department of Gastroenterology, Liverpool Hospital, NSW, Australia
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Koo JH, Lee WH, Lee CG, Kim SG. Fyn inhibition by cycloalkane-fused 1,2-dithiole-3-thiones enhances antioxidant capacity and protects mitochondria from oxidative injury. Mol Pharmacol 2012; 82:27-36. [PMID: 22474169 DOI: 10.1124/mol.111.077149] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Fyn kinase has emerged as a regulator of diverse pathological processes. However, therapeutic Fyn inhibitors are not available. This study investigated the potential of a series of cycloalkane-fused dithiolethiones (CDTs) or other congeners to increase antioxidant capacity in association with Fyn inhibition, as well as the molecular basis for this effect. Treatment of HepG2 cells with each agent protected the mitochondria from oxidative injury elicited by arachidonic acid and iron, which increased cell viability; 4,5,6,7-tetrahydrobenzo-1,2-dithiole-3-thione (SNU1A) and 5,6-dihydro-4H-cyclopenta-1,2-dithiole-3-thione (SNU2A) were the most effective, whereas 5-methyl-1,2-dithiole-3-thione (SNU3A) was less active. 5-(Quinolin-2-yl)-1,2-dithiole-3-thione (SNU3E) had a minimal effect. SNU1A treatment decreased mitochondrial superoxide production and enabled cells to restore mitochondrial membrane permeability. Oxidative injury caused by arachidonic acid and iron enhanced Fyn phosphorylation at a tyrosine residue, which was decreased by SNU1A treatment. 2,3-Dihydro-N,N-dimethyl-2-oxo-3-[(4,5,6,7-tetrahydro-1H-indol-2-yl)methylene]-1H-indole-5-sulfonamide (SU6656), a known Fyn inhibitor, had a similar effect. Fyn inhibition contributed to protecting mitochondria from injury through AMP-activated protein kinase (AMPK), as supported by reversal of this effect with Fyn overexpression. Consistently, Fyn overexpression attenuated AMPK activation by SNU1A, which strengthens the inhibitory role of Fyn in AMPK activity. CDTs had antioxidant effects, as shown by increases in GSH contents and inhibition of H(2)O(2) production. They also had the ability to activate nuclear factor E2-related factor 2 (Nrf2), a key antioxidant transcription factor. Fyn overexpression decreased the Nrf2 activation induced by SNU1A. Our results demonstrate that CDTs exert cytoprotective effects by protecting mitochondria and increasing the cellular antioxidant capacity, which may result not only from Fyn inhibition leading to AMPK activation but also from Nrf2 activation.
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Affiliation(s)
- Ja Hyun Koo
- Innovative Drug Research Center for Metabolic and Inflammatory Disease, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Korea
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Koo JH, Lee WH, Kim SG. Enhancement of antioxidant capacity by novel dithiolethiones as a consequence of Fyn inhibition. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.839.2] [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)
- Ja Hyun Koo
- College of pharmacySeoul National UniversitySeoulKorea, Republic of
| | - Woo Hyung Lee
- College of pharmacySeoul National UniversitySeoulKorea, Republic of
| | - Sang Geon Kim
- College of pharmacySeoul National UniversitySeoulKorea, Republic of
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Jung HN, Chung MJ, Koo JH, Kim HC, Lee KS. Digital tomosynthesis of the chest: Utility for detection of lung metastasis in patients with colorectal cancer. Clin Radiol 2012; 67:232-8. [PMID: 21939964 DOI: 10.1016/j.crad.2011.08.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 08/03/2011] [Accepted: 08/12/2011] [Indexed: 12/21/2022]
Affiliation(s)
- H N Jung
- Department of Radiology and Center for Imaging Science, Sungkyunkwan University School of Medicine, Seoul, Korea
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Jacobs CJ, Tate JS, Olson B, Theodoropoulou N, Koo JH. Thermal characterization of polyamide 11/nanographene platelet nanocomposites. J Nanosci Nanotechnol 2012; 12:1799-1805. [PMID: 22754983 DOI: 10.1166/jnn.2012.5158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The objective of this study is to evaluate thermal properties of polyamide 11 (PA11)/nanographene platelet (NGP) nanocomposites. Samples were prepared using 1 wt%, 3 wt%, and 5 wt% of NGPs. Isopropyl alcohol (IPA) was used as a solvent to assist in dispersion of the NGPs within the PA11 powder. The NGPs were hand mixed evenly into the PA11 powder using a wooden dowel. Morphological characterization of the PA11/NGP nanocomposite was conducted using scanning electron microscopy. Thermal characterization of nanocomposites includes thermogravimetric analysis, differential scanning calorimetry and thermomechanical analysis. Results indicate that the addition of NGPs shows an initial increase in thermal stability and crystallization temperature (T(c)) along with a decrease in glass transition temperature (T(g)) and no improvement in coefficient of thermal expansion (alpha). These results are attributed to improved interfacial adhesion between NGPs and PA11, restricting polymer chain mobility.
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Affiliation(s)
- C J Jacobs
- Ingram School of Engineering, Texas State University-San Marcos, 601 University Drive, San Marcos, Texas 78666-4616, USA
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Kim YK, Koo JH, Kim KS, Kim SH. Suppressing harmonic vibrations of a miniature cryogenic cooler using an adaptive tunable vibration absorber based on magneto-rheological elastomers. Rev Sci Instrum 2011; 82:035103. [PMID: 21456785 DOI: 10.1063/1.3553198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This paper presents dynamic performances of an adaptive tunable vibration absorber (TVA) designed to suppress the main harmonic disturbance of a miniature linear cryogenic cooler, which is being used in space applications such as an observation satellite. The adaptive TVA employs a magneto-rheological elastomer (MRE) for a variable stiffness element. This study first investigates the shear modulus change of MRE samples with respect to the magnetic flux density, which varies through the alignment of particle chains. The MRE with the maximal shear modulus change is mounted for the TVA on a prototype cooler, which emulates the characteristics of a miniature cryogenic cooler. Using the test setup, a series of vibration tests are performed to evaluate the performance and efficacy of the MRE TVA and its re-tuning ability. The experimental results show that the MRE TVA is able to robustly suppress the vibration of the cooler even when the frequency of resonant vibration is changed up to 87% from its initial frequency.
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Affiliation(s)
- Y-K Kim
- Department of Mechanical Engineering, KAIST, Daejeon, 305-701, South Korea
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Song HY, Kim JH, Shin JH, Kim HC, Yu CS, Kim JC, Kang SG, Yoon CJ, Lee JY, Koo JH, Lee KH, Kim JK, Kim DH, Shin TB, Jung GS, Han YM. A dual-design expandable colorectal stent for malignant colorectal obstruction: results of a multicenter study. Endoscopy 2007; 39:448-54. [PMID: 17516352 DOI: 10.1055/s-2007-966270] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [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] [Indexed: 02/02/2023]
Abstract
BACKGROUND AND STUDY AIMS It is known that metal stent placement is safe, easy, and effective for the treatment of malignant colorectal obstruction, but these stents are associated with delayed complications of tumor ingrowth and stent migration. The aim of this study was to prospectively investigate the technical feasibility, clinical effectiveness, and safety of a dual-design colorectal stent (consisting of an outer stent and an inner bare nitinol stent) in patients with malignant colorectal obstruction. PATIENTS AND METHODS Placement of the dual stent using a 4.5-mm stent delivery system was attempted in 151 patients with malignant colorectal obstruction, either before surgery (n = 50) or for palliation (n = 101). Multivariate logistic regression analysis was used to identify risk factors associated with complications. RESULTS Stent placement was technically successful in 145/151 patients (96%). Of the patients who had a technically successful placement, bowel obstruction resolved within 2 days after stent placement in 48/50 (96%) of the patients in the bridge-to-surgery group and in 87/95 (92%) of the patients in the palliative group. Perforation occurred in 16 patients, incomplete stent expansion in eight patients, stent migration in four patients, tumor overgrowth in five patients, severe rectal pain in five patients, and bleeding in eight patients. Complete obstruction was the only significant risk factor for perforation (odds ratio 6.88, 95% CI 2.04-23.17, P = 0.002). In the palliative group, the median survival was 152.0 days and the mean survival was 263.8 days. CONCLUSIONS The dual stent with a 4.5-mm stent delivery system is easy to insert, safe, and reasonably effective for the palliative treatment of malignant colorectal obstruction. However, a great deal of care is needed in its deployment because of the high rate of perforation.
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Affiliation(s)
- H-Y Song
- Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
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Abstract
A general method to quantify the inclusion dispersion of mixture microstructures has been developed. The dispersion quantity, D, is defined as the probability of inclusion particle free-path spacing falling into a certain range of the mean spacing mu, according to the particle spacing data frequency distribution. Two quantities, D(0.1) and D(0.2), are proposed, which are the probabilities of the particle free-path spacing falling into the ranges of mu+/- 0.1 mu and mu+/- 0.2 mu, respectively. Both normal and lognormal distributions are discussed, and in both cases, the quantities D(0.1) and D(0.2) are specified as monotonous increasing functions of mu/sigma, where mu and sigma; are the mean particle free-path spacing and standard deviation, respectively. Examples of composite are presented to quantify the dispersion of foreign reinforcements based on the proposed method.
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Affiliation(s)
- Z P Luo
- Microscopy and Imaging Center, Biological Sciences Building West, Texas A&M University, College Station, TX 77843-2257, USA.
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Cho WH, Kim HT, Koo JH, Lee IK. Effect of AP-1 decoy using hemagglutinating virus of Japan-liposome on the intimal hyperplasia of the autogenous vein graft in mongrel dogs. Transplant Proc 2006; 38:2161-3. [PMID: 16980031 DOI: 10.1016/j.transproceed.2006.06.103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Intimal hyperplasia is the leading cause of late vein graft failure. Smooth muscle cell proliferation and migration is the underlying mechanism. Pharmacological approaches to prolong vein graft patency have produced limited results. AP-1 proteins play a role in the expression of many genes involved in cellular proliferation and cell cycle progression. Previously we reported inhibition of vascular smooth muscle cell migration, proliferation, and intimal hyperplasia in the balloon-injured rat carotid artery using an AP-1 decoy with HVJ-liposomes. In this report, we evaluated the effect of the AP-1 decoy on intimal hyperplasia in a large animal model. The jugular vein was transfected with hemagglutinating virus of Japan-liposomes containing the AP-1 decoy or scrambled oligonucleotides. An interposition graft was performed with the pretreated jugular vein between the transected femoral arteries. The graft was harvested at 16 weeks after the procedure. The intimal area was compared: the intimal area of the AP-1 decoy-treated versus control group was 47.3 +/- 15.2 versus 102.3 +/- 15.9 (P < .05), respectively. In conclusion, AP-1 decoy using HVJ-liposomes effectively prevented intimal hyperplasia of an autogenous vein graft in mongrel dogs.
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Affiliation(s)
- W H Cho
- Department of Surgery, Dongsan Medical Center, Keimyung University 194, Dongsan-dong, Jung-gu, Daegu, South Korea.
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Ro YT, Lee HI, Kim EJ, Koo JH, Kim E, Kim YM. Purification, characterization, and physiological response of a catalase-peroxidase in Mycobacterium sp. strain JC1 DSM 3803 grown on methanol. FEMS Microbiol Lett 2003; 226:397-403. [PMID: 14553939 DOI: 10.1016/s0378-1097(03)00644-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A novel catalase-peroxidase (CP) from methanol-grown cells of Mycobacterium sp. strain JC1 was purified. The CP exhibited properties of both typical mycobacterial CPs (i.e. strict pH optimum, labile to heat treatment, capable of oxidizing NADH, and resistant to inhibition by 3-amino-1,2,4-triazole) and true catalases (i.e. stable against ethanol-chloroform treatment). The enzyme oxidized methanol and shared common antigenic groups with other mycobacteria. Isoniazid had almost no effect on the growth and expression of CP but inhibited the enzyme activity to some extent. Sodium nitroprusside arrested the growth but strongly stimulated the expression of CP with a concomitant increase in activity after the mid-exponential growth phase.
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Affiliation(s)
- Young Tae Ro
- Laboratory of Biochemistry, College of Medicine, Konkuk University, Chungju 380-701, South Korea
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Lee HS, Joo KB, Song HT, Kim YS, Park DW, Park CK, Lee WM, Park YW, Koo JH, Song SY. Relationship between sonographic and pathologic findings in epidermal inclusion cysts. J Clin Ultrasound 2001; 29:374-383. [PMID: 11579399 DOI: 10.1002/jcu.1052] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
PURPOSE We evaluated the sonographic findings in epidermal inclusion cysts and related them to the pathologic findings. METHODS We retrospectively reviewed the sonograms and pathology specimens of 24 patients with pathologically proven epidermal inclusion cysts. We evaluated the lesions for shape, size, internal echogenicity, posterior sound enhancement, and presence of color Doppler signals. We classified the masses into 5 sonographic types according to their internal echogenicity. The relationship between the sonographic types and the pathologic findings was examined. RESULTS The masses were ovoid or spherical in 17 cases (71%), lobulated in 5 (21%), and tubular in 2 (8%). The longest diameter ranged from 1 to 6 cm (mean, 3.1 cm). Twenty-three cases (96%) were associated with posterior sound enhancement. Color Doppler signals were absent in 20 cases, but some vascularity was noted in 4 ruptured epidermal cysts, in areas of granulation tissue. The most common sonographic type was a hypoechoic lesion with scattered echogenic reflectors (10 cases). Sonographic findings were related to the lamellation of keratin debris and the granulation tissue secondary to rupture. Most cases with a lobulated configuration (4 of 5) or color Doppler signals (4 of 4) were ruptured cysts. CONCLUSIONS Epidermal inclusion cysts most often appeared sonographically as a hypoechoic mass containing variable echogenic foci without color Doppler signals. Ruptured epidermal cysts, however, may have lobulated contours and show color Doppler signals, mimicking a solid mass.
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Affiliation(s)
- H S Lee
- Department of Diagnostic Radiology, College of Medicine, Hanyang University, 17, Haengdang-Dong, Seungdong-Gu, Seoul 133-792, South Korea
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Noh YH, Kim JA, Lim GR, Ro YT, Koo JH, Lee YS, Han DS, Park HK, Ahn MJ. Detection of circulating tumor cells in patients with gastrointestinal tract cancer using RT-PCR and its clinical implications. Exp Mol Med 2001; 33:8-14. [PMID: 11322488 DOI: 10.1038/emm.2001.2] [Citation(s) in RCA: 16] [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] [Indexed: 12/23/2022] Open
Abstract
To investigate the relationship between the presence of circulating tumor cells in different stages of gastrointestinal tract cancer and the subsequent relapse or distant metastasis, circulating levels of CEA mRNA was serially examined at an interval of 10.6+/-4.5 or 13.7+/-3.0 months in gastric or colorectal cancer patients, respectively. CEA mRNA was measured by means of RT-PCR amplification as an indicator for micrometastatic malignant cells. Seven of twenty-nine respectable gastric cancer patients (24.1%) [EGC: 2/9 (22.2%), AGC IIIa: 1/5 (20.0%), AGC IIIb: 4/15 (26.6%)] were positive for CEA mRNA on the initial test and 10 of 29 patients (34.4%) [EGC: 2/ 9 (22.2%), AGC IIIa: 1/5 (20.0%), AGC IIIb: 7/15 (46.7%)] were positive on a follow-up test. Only in AGC IIIb, the positive rate for CEA mRNA increased about twice and 6 of 7 positive cases (85.7%) relapsed within 2.6+/-2.4 months after the follow-up test. In colorectal cancer, 4 of 19 patients (21.1%) [B2: 1/6 (16.7%), C2: 3/13 (23.0%)] were positive on the initial test and 10 of 19 patients (52.6%) [B2: 4/6 (66.7%), C2: 6/13 (46.2%)] were positive on a follow-up test showing an increase in positive rates during a follow-up, however, no significant correlation between CEA mRNA positivity and subsequent relapse was demonstrated. These results suggest that an early tumor cell dissemination may occur in gastrointestinal tract cancer without subsequent relapse, however, the serial regular examination of CEA mRNA level may contribute to predicting a subsequent relapse in AGC IIIb in gastric cancer.
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Affiliation(s)
- Y H Noh
- Department of Biochemistry, College of Medicine, Konkuk University, Chungju, Korea
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Abstract
Although biofilm formation is widely documented on Earth, it has not been demonstrated in the absence of gravity. To explore this possibility, Pseudomonas aeruginosa, suspended in sterile buffer, was flown in a commercial payload on space shuttle flight STS-95. During earth orbit, biofilm formation was induced by exposing the bacteria to sterile media through a 0.2-microm (pore size) polycarbonate membrane. Examination of these membranes by confocal microscopy revealed biofilms to be present and that these biofilms could persist in spite of vigorous agitation. These results represent the first report of biofilm formation under microgravity conditions.
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Affiliation(s)
- R J McLean
- Department of Biology, Southwest Texas State University, San Marcos, 78666, USA.
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Koo JH, Cho IH, Kim YS. The malonate decarboxylase operon of Acinetobacter calcoaceticus KCCM 40902 is regulated by malonate and the transcriptional repressor MdcY. J Bacteriol 2000; 182:6382-90. [PMID: 11053382 PMCID: PMC94784 DOI: 10.1128/jb.182.22.6382-6390.2000] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A regulatory gene-like open reading frame oriented oppositely to mdcL, coined mdcY, was found upstream from the structural genes of the mdcLMACDEGBH operon in Acinetobacter calcoaceticus KCCM 40902. To elucidate the function of this gene, mdcY was expressed in Escherichia coli, and the MdcY protein was purified to homogeneity. Its DNA binding activity and binding site were examined by gel retardation and footprinting assays in vitro and by site-directed mutagenesis of the binding sites in vivo. The regulator bound target DNA regardless of the presence of malonate, and the binding site was found centered at -65 relative to the mdcL transcriptional start site and contains a 12-bp palindromic structure (5'-ATTGTA/TACAAT-3'). Using a promoter fusion to the reporter gene luc, we found that the promoter P(mdcY) is negatively regulated by MdcY independent of malonate. However, the promoter P(mdcL) recovered its activity in the presence of malonate. When mdcY was introduced into A. calcoaceticus KCCM 40902 in which the gene is inactivated by an IS3 family element, malonate decarboxylase was significantly repressed in cultures growing in acetate, succinate, or Luria-Bertani medium. However, in cells growing in malonate, malonate decarboxylase was induced, indicating that MdcY is a transcriptional repressor and that malonate or a product resulting from malonate metabolism should be the intracellular inducer of the mdc operon.
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Affiliation(s)
- J H Koo
- Department of Biochemistry, College of Science, Protein Network Research Center, Institute of Bioscience and Biotechnology, Yonsei University, Seoul 120-749, Korea
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Abstract
The genomic locus containing the potential repressor gene mdcY (inactivated by a putative IS3 element) and the mdcLMACDEGBH genes from Acinetobacter calcoaceticus was cloned and sequenced. In order to evaluate the biochemical function of the protein components, the genes were expressed independently and their activities predicted by database analysis. The mdcA gene product, the alpha subunit, was found to be malonate/acetyl-CoA transferase and the mdcD gene product, the beta subunit, was found to be malonyl-CoA decarboxylase. The mdcE gene product, the gamma subunit, may play a role in subunit interaction to form a stable complex or as a codecarboxylase. The mdcC gene product, the delta subunit, was an acyl-carrier protein, which has a unique CoA-like prosthetic group. Various combinations of malonate decarboxylase subunits allowed us to estimate their contribution to malonyl-CoA decarboxylase activity. The prosthetic group was identified as carboxymethylated 2'-(5"-phosphoribosyl)-3'-dephospho-CoA by mass spectrometry. The mdcH gene product was determined to have malonyl-CoA/dephospho-CoA acyltransferase activity. Using database analysis mdcLM, mdcG, mdcB and mdcI were estimated to be the genes for a malonate transporter, a holo-acyl carrier synthase, protein for the formation of precursor of the prosthetic group and a regulatory protein, respectively. From the data shown above we propose a metabolic pathway for malonate in A. calcoaceticus.
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Affiliation(s)
- J H Koo
- Department of Biohemistry, College of Science, Bioproducts Research Center, Yonsei University, Seoul, Korea
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Abstract
Malonate decarboxylases, which catalyze the conversion of malonate to acetate, can be classified into biotin-dependent and biotin-independent enzymes. In order to reveal the stereochemical course of the reactions catalyzed by the biotin-independent enzymes from Acinetobacter calcoaceticus and Pseudomonas fluorescens, a chiral substrate, malonate carrying (13)C in one carboxyl group and (3)H at one of the methylene positions, was prepared and used in the reactions catalyzed by these two enzymes. The decarboxylation of (R)-[1-(13)C(1), 2-(3)H]malonate in (2)H(2)O gave a pseudo-racemate of chiral acetate which was converted via acetyl-CoA into malate with malate synthase. From the relative proportions of the isotopomers of malate present, determined by (3)H NMR analysis, it was concluded that in the decarboxylation of malonate by these two biotin-independent enzymes COOH is replaced by H with retention of configuration. The same stereochemical outcome had been previously observed for the reaction catalyzed by the biotin-dependent malonate decarboxylase from Malonomonas rubra (J. Micklefield et al. J. Am. Chem. Soc. 117, 1153-1154, 1995).
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Affiliation(s)
- S Handa
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA
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Abstract
Gitelman's syndrome is a primary renal tubular disorder with hypokalemic metabolic alkalosis, hypocalciuria, and magnesium deficiency. Short stature is one of clinical manifestations in children. The pathogenesis of short stature in Gitelman's syndrome is not known. To evaluate whether growth hormone (GH) is deficient and whether recombinant human GH (rhGH) improves growth rate, rhGH therapy was tried in a child with Gitelman's syndrome. Both height and body weight were less than the third percentile. Laboratory and radiologic findings suggested GH deficiency. During the first 6 months, rhGH therapy with potassium supplement markedly elevated growth rate from 3.8 cm/yr to 12.0 cm/yr. After cessation of rhGH, height increment markedly decreased to the pretreatment level of 3.6 cm/yr during the second 6 months. Additionally, hypomagnesemia was corrected after rhGH therapy. Accordingly, GH deficiency may contribute to short stature in children with Gitelman's syndrome, and rhGH therapy would be an excellent adjunctive treatment for short children with Gitelman's syndrome whose condition is resistant to conventional therapies in terms of growth.
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Affiliation(s)
- C W Ko
- Department of Pediatrics, Kyungpook National University School of Medicine, Taegu, South Korea.
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Abstract
A 26-year-old woman presented with epigastric pain, vomiting, and a palpable mass in the right lower abdomen. Ultrasonography showed a high echogenic mass associated with a small amount of ascites in the right lower abdomen. Computed tomography demonstrated entrapped ileal loops within a thin-walled fibrous capsule. A thin fibrous sac encasing the terminal ileum was detected on laparotomy and confirmed as idiopathic sclerosing encapsulating peritonitis.
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Affiliation(s)
- M Y Kim
- Department of Diagnostic Radiology, Inha University Hospital, Tae-pyung-dong 7336, Su-jung-gu, Kyung-gi-do 461-192, Sung-nam City, South Korea
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Koo JH, Jung SB, Byun HS, Kim YS. Cloning and sequencing of genes encoding malonate decarboxylase in Acinetobacter calcoaceticus. Biochim Biophys Acta 1997; 1354:49-54. [PMID: 9375791 DOI: 10.1016/s0167-4781(97)00134-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Malonate decarboxylase from Acinetobacter calcoaceticus was isolated and characterized (Kim, Y.S., Byun, H.S., J. Biol. Chem. 269 (1994) 29636-29641), and its subunits were reanalyzed recently to be alpha, beta, gamma, and delta. The genes for the subunits, MdcA (548 a.a.), B (295 a.a.), C (238 a.a.), and D (102 a.a.), of the enzyme have been cloned by using oligonucleotide primers deduced from amino acid sequences of peptides isolated from the purified enzyme, and sequenced to be clustered in an operon in the order of A-D-B-C. The operon was found to encode more genes than mdcABCD. The Escherichia coli, transformed with the vector containing the insert mdcADBC and about 1.7 kb of an upstream region, expressed the four subunits of the enzyme but the proteins did not show enzyme activity. It indicates that, like the enzymes from Malonomonas rubra and Klebsiella pneumoniae, more genes are needed for the formation of the functional malonate decarboxylase.
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Affiliation(s)
- J H Koo
- Department of Biochemistry, College of Science, Bioproducts Research Center, Yonsei University, Seoul, South Korea
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