1
|
Stefaniuk-Szmukier M, Piórkowska K, Ropka-Molik K. Equine Metabolic Syndrome: A Complex Disease Influenced by Multifactorial Genetic Factors. Genes (Basel) 2023; 14:1544. [PMID: 37628596 PMCID: PMC10454496 DOI: 10.3390/genes14081544] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/10/2023] [Accepted: 07/26/2023] [Indexed: 08/27/2023] Open
Abstract
Equine metabolic syndrome (EMS) has become an important issue in modern veterinary medicine and is linked to the common, extremely painful, most-of-the-time performance-terminating hoof laminitis. The growing knowledge in the field of genetic background, inducing environmental factors, diagnosis, treatment and maintenance of affected equines led us to summarise the available information to be used not only for scientific purposes but for fieldwork. In horses, the clinical presentation of EMS includes: obesity or local fat deposition, bilateral lameness or hoof rings attributed to ongoing or previous (pasted) laminitis with the key feature of the occurrence of insulin dysregulation, disturbing the homeostasis within insulin, glucose and lipid metabolism. The management of EMS is based on dietary and fitness discipline; however, intensive research is ongoing in the field of regenerative medicine to develop modern and promising therapies.
Collapse
Affiliation(s)
- Monika Stefaniuk-Szmukier
- Department of Animal Molecular Biology, National Research Institute of Animal Production, Krakowska 1, 32-083 Balice, Poland
| | | | | |
Collapse
|
2
|
Liu YY, Bai JS, Liu CC, Zhou JF, Chen J, Cheng Y, Zhou B. The Small GTPase Rab14 Regulates the Trafficking of Ceramide from Endoplasmic Reticulum to Golgi Apparatus and Facilitates Classical Swine Fever Virus Assembly. J Virol 2023; 97:e0036423. [PMID: 37255314 PMCID: PMC10231254 DOI: 10.1128/jvi.00364-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 03/24/2023] [Indexed: 06/01/2023] Open
Abstract
Classical swine fever virus (CSFV) is a highly pathogenic RNA virus belonging to the Flaviviridae family that can cause deadly classical swine fever (CSF) in pigs. However, the molecular details of virus replication in the host are still unclear. Our previous studies have reported that several Rab proteins mediate CSFV entry into host cells, but it is unknown whether CSFV hijacks other Rab proteins for effective viral infection. Here, we systematically studied the role of Rab14 protein in regulating lipid metabolism for promoting viral assembly. First, Rab14 knockdown and overexpression significantly affected CSFV replication, indicating the essential role of Rab14 in CSFV infection. Interestingly, Rab14 could significantly affect virus replication in the late stage of infection. Mechanistically, CSFV NS5A recruited Rab14 to the ER, followed by ceramide transportation to the Golgi apparatus, where sphingomyelin was synthesized. The experimental data of small molecule inhibitors, RNA interference, and replenishment assay showed that the phosphatidylinositol-3-kinase (PI3K)/AKT/AS160 signaling pathway regulated the function of Rab14 to affect the transport of ceramide. More importantly, sphingomyelin on the Golgi apparatus contributed to the assembly of viral particles. Blockage of the Rab14 regulatory pathway induced the reduction of the content of sphingomyelin on the Golgi apparatus, impairing the assembly of virus particles. Our study clarifies that Rab14 regulates lipid metabolism and promotes CSFV replication, which provides insight into a novel function of Rab14 in regulating vesicles to transport lipids to the viral assembly factory. IMPORTANCE The Rab protein family members participate in the viral replication of multiple viruses and play important roles in the virus infection cycle. Our previous research focused on Rab5/7/11, which regulated the trafficking of vesicles in the early stage of CSFV infection, especially in viral endocytosis. However, the role of other Rab proteins in CSFV replication is unclear and needs further clarification. Strikingly, we screened some Rabs and found the important role of Rab14 in CSFV infection. Virus infection mobilized Rab14 to regulate the vesicle to transport ceramide from the ER to the Golgi apparatus, further promoting the synthesis of sphingomyelin and facilitating virus assembly. The treatment of inhibitors showed that the lipid transport mediated by Rab14 was regulated by the PI3K/AKT/AS160 signaling pathway. Knockdown of Rab14 or the treatment with PI3K/AKT/AS160 inhibitors reduced the ceramide content in infected cells and hindered virus assembly. Our study is the first to explain that vesicular lipid transport regulated by Rab promotes CSFV assembly, which is conducive to the development of antiviral drugs.
Collapse
Affiliation(s)
- Ya-Yun Liu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Ji Shan Bai
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Chun-Chun Liu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Jiang-Fei Zhou
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Jing Chen
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Yan Cheng
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Bin Zhou
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| |
Collapse
|
3
|
Kamal AHM, Chakrabarty JK, Chowdhury SM. Lipopolysaccharide and statin-mediated immune-responsive protein networks revealed in macrophages through affinity purification spacer-arm controlled cross-linking (AP-SPACC) proteomics. Mol Omics 2023; 19:48-59. [PMID: 36377691 DOI: 10.1039/d2mo00224h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Toll-like receptor 4 (TLR4), a pattern recognition receptor, is activated by lipopolysaccharides (LPS) and induces the MyD88 pathway, which subsequently produces pro-inflammatory cytokines through activation of transcriptional nuclear factor (NF)-κB. Statins have been widely prescribed to reduce cholesterol synthesis for patients with cardiovascular disease. Statins may have pleiotropic effects, which include anti- and pro-inflammatory effects on cells. The molecular mechanism of the sequential influence of LPS and statin on the innate immune system remains unknown. We employed affinity purification-spacer-arm controlled cross-linking (AP-SPACC) MS-based proteomics analysis to identify the LPS- and statin-LPS-responsive proteins and their networks. LPS-stimulated RAW 264.7 macrophage cells singly and combined with the drug statin used in this study. Two chemical cross-linkers with different spacer chain lengths were utilized to stabilize the weak and transient interactors. Proteomic analysis identified 1631 differentially expressed proteins. We identified 151 immune-response proteins through functional enrichment analysis and visualized their interaction networks. Selected candidate protein-coding genes were validated, specifically squamous cell carcinoma antigens recognized by T cells 3, sphingosine-1-phosphate lyase 1, Ras-related protein Rab-35, and tumor protein D52 protein-coding genes through transcript-level expression analysis. The expressions of those genes were significantly increased upon statin treatment and decreased in LPS-stimulated macrophage cells. Therefore, we presumed that the expression changes of genes occurred due to immune response during activation of inflammation. These results highlight the immune-responsive proteins network, providing a new platform for novel investigations and discovering future therapeutic targets for inflammatory diseases.
Collapse
Affiliation(s)
- Abu Hena Mostafa Kamal
- Department of Chemistry and Biochemistry, University of Texas at Arlington, TX, 76019, USA. .,Advanced Technology Cores, Dan L Duncan Comprehensive Cancer Center, Metabolomics Core, Baylor College of Medicine, Houston, TX, 77030, USA.,Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Jayanta K Chakrabarty
- Department of Chemistry and Biochemistry, University of Texas at Arlington, TX, 76019, USA. .,Quantitative Proteomics and Metabolomics Center, Columbia University, New York, NY, 10027, USA
| | - Saiful M Chowdhury
- Department of Chemistry and Biochemistry, University of Texas at Arlington, TX, 76019, USA.
| |
Collapse
|
4
|
Behl T, Kaur D, Sehgal A, Singh S, Makeen HA, Albratty M, Abdellatif AAH, Dachani SR, Bungau S. Exploring the potential role of rab5 protein in endo-lysosomal impairment in Alzheimer's disease. Biomed Pharmacother 2022; 148:112773. [PMID: 35245734 DOI: 10.1016/j.biopha.2022.112773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 02/18/2022] [Accepted: 02/27/2022] [Indexed: 11/02/2022] Open
Abstract
Growing evidence suggests that neuronal dysfunction in the endo-lysosomal and autophagic processes contributes to the onset and progression of neurodegenerative diseases such as Alzheimer's disease (AD). Since they are the primary cellular systems involved in the production and clearance of aggregated amyloid plaques, endo-lysosomal or autophagic equilibrium must be maintained throughout life. As a result, variations in the autophagic and endo-lysosomal torrent, as a measure of degenerative function in these sections or pathways, may have a direct impact on disease-related processes, such as Aß clearance from the brain and interneuronal deposition of Aß and tau aggregates, thus disrupting synaptic plasticity. The discovery of several chromosomal factors for Alzheimer's disease that are clinically linked to regulation of the endocytic pathway, including protein aggregation and removal, supports the theory that the endo-lysosomal/autophagic torrent is more susceptible to impairment, especially as people age, thus catalysing the onset of disease. Although the role of endo-lysosomal/autophagic dysfunction in neurodegeneration has progressed in recent years, the field remains underdeveloped. Because of its possible therapeutic implications in Alzheimer's disease, further study is needed to explain the possibilities for effective autophagy regulation.
Collapse
Affiliation(s)
- Tapan Behl
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India.
| | - Dapinder Kaur
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India
| | - Aayush Sehgal
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India
| | - Sukhbir Singh
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India
| | - Hafiz A Makeen
- Pharmacy Practice Research Unit, Clinical Pharmacy, Department, College of Pharmacy, Jazan University, P.O. Box-114, Jazan 45142, Saudi Arabia
| | - Mohammed Albratty
- Department of Pharmaceutical Chemistry, College of Pharmacy, Jazan University, P.O. Box 114, Jazan 45142, Saudi Arabia
| | - Ahmed A H Abdellatif
- Department of Pharmaceutics, College of Pharmacy, Qassim University, Buraydah 51452, Saudi Arabia; Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Al-Azhar University, Assiut 71524, Egypt
| | - Sudharshan Reddy Dachani
- Department of Pharmacy Practice & Pharmacology, College of Pharmacy, Shaqra University, Al-Dawadmi Campus, Al-Dawadmi 11961, Saudi Arabia
| | - Simona Bungau
- Department of Pharmacy, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania.
| |
Collapse
|
5
|
Kang BB, Chiang BH. A novel phenolic formulation for treating hepatic and peripheral insulin resistance by regulating GLUT4-mediated glucose uptake. J Tradit Complement Med 2022; 12:195-205. [PMID: 35528476 PMCID: PMC9072824 DOI: 10.1016/j.jtcme.2021.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 08/07/2021] [Accepted: 08/07/2021] [Indexed: 11/26/2022] Open
|
6
|
Furuhata R, Kabe Y, Kanai A, Sugiura Y, Tsugawa H, Sugiyama E, Hirai M, Yamamoto T, Koike I, Yoshikawa N, Tanaka H, Koseki M, Nakae J, Matsumoto M, Nakamura M, Suematsu M. Progesterone receptor membrane associated component 1 enhances obesity progression in mice by facilitating lipid accumulation in adipocytes. Commun Biol 2020; 3:479. [PMID: 32887925 PMCID: PMC7473863 DOI: 10.1038/s42003-020-01202-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 08/03/2020] [Indexed: 12/26/2022] Open
Abstract
Progesterone receptor membrane associated component 1 (PGRMC1) exhibits haem-dependent dimerization on cell membrane and binds to EGF receptor and cytochromes P450 to regulate cancer proliferation and chemoresistance. However, its physiological functions remain unknown. Herein, we demonstrate that PGRMC1 is required for adipogenesis, and its expression is significantly enhanced by insulin or thiazolidine, an agonist for PPARγ. The haem-dimerized PGRMC1 interacts with low-density lipoprotein receptors (VLDL-R and LDL-R) or GLUT4 to regulate their translocation to the plasma membrane, facilitating lipid uptake and accumulation, and de-novo fatty acid synthesis in adipocytes. These events are cancelled by CO through interfering with PGRMC1 dimerization. PGRMC1 expression in mouse adipose tissues is enhanced during obesity induced by a high fat diet. Furthermore, adipose tissue-specific PGRMC1 knockout in mice dramatically suppressed high-fat-diet induced adipocyte hypertrophy. Our results indicate a pivotal role of PGRMC1 in developing obesity through its metabolic regulation of lipids and carbohydrates in adipocytes.
Collapse
Affiliation(s)
- Ryogo Furuhata
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
- Department of Orthopaedic[s] Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Yasuaki Kabe
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
- Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Tokyo, Japan.
| | - Ayaka Kanai
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Yuki Sugiura
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Hitoshi Tsugawa
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Eiji Sugiyama
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Miwa Hirai
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Takehiro Yamamoto
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Ikko Koike
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Noritada Yoshikawa
- Department of Rheumatology and Allergy, IMSUT Hospital, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Hirotoshi Tanaka
- Department of Rheumatology and Allergy, IMSUT Hospital, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Masahiro Koseki
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Suita, Osaka, 565-0871, Japan
| | - Jun Nakae
- Department of Physiology, International University of Health and Welfare School of Medicine, Narita, 286-8686, Japan
| | - Morio Matsumoto
- Department of Orthopaedic[s] Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Masaya Nakamura
- Department of Orthopaedic[s] Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Makoto Suematsu
- Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
| |
Collapse
|
7
|
Chao H, Deng L, Xu F, Fu B, Zhu Z, Dong Z, Liu YN, Zeng T. RAB14 activates MAPK signaling to promote bladder tumorigenesis. Carcinogenesis 2020; 40:1341-1351. [PMID: 30809635 DOI: 10.1093/carcin/bgz039] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 01/22/2019] [Accepted: 02/24/2019] [Indexed: 12/16/2022] Open
Abstract
Bladder cancer (BC) is a fatal invasive malignancy accounting for approximately 5% of all cancer deaths in humans; however, the underlying molecular mechanisms and potential targeted therapeutics for BC patients remain unclear. We report herein that RAB14 was overexpressed in BC tissues and cells with high metastatic potential and its abundance was significantly associated with lymph node metastasis (P = 0.001), a high-grade tumor stage (P = 0.009), poor differentiation (P < 0.001) and unfavorable prognoses of BC patients (P = 0.003, log-rank test). Interference by RAB14 mediated a reduction in the TWIST1 protein and inhibited cell migration and invasion (P < 0.05). Moreover, silencing RAB14 reduced cell proliferation and induced apoptosis in vitro and suppressed tumorigenesis in a mouse xenograft model. We demonstrated that RAB14-promoted BC cancer development and progression were associated with activation of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase signaling through upregulation of MAPK1/MAPK8 and downregulation of dual-specificity protein phosphatase 6/Src homology 2 domain containing transforming protein/Fos proto-oncogene, AP-1 transcription factor subunit (FOS). We provide evidence that RAB14 acts as a tumor promoter and modulates the invasion and metastatic potential of BC cells via activating the MAPK pathway.
Collapse
Affiliation(s)
- Haichao Chao
- Institute of Clinical Medicine, Jiangxi Provincial People's Hospital Affiliated to Nanchang University, Nanchang, P.R. China
| | - Leihong Deng
- Medical Department of Graduate School, Nanchang University, Nanchang, P.R. China
| | - Fanghua Xu
- Pathology Department, Jiangxi Provincial People's Hospital Affiliated to Nanchang University, Nanchang, P.R. China
| | - Bin Fu
- Department of Urology, The First Affiliated Hospital of Nanchang University, Nanchang, P.R. China
| | - Zunwei Zhu
- Department of Urology, Jiangxi Provincial People's Hospital Affiliated to Nanchang University, Nanchang, P.R. China
| | - Zhifeng Dong
- Medical Department of Graduate School, Nanchang University, Nanchang, P.R. China
| | - Yen-Nien Liu
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.,Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Tao Zeng
- Department of Urology, Jiangxi Provincial People's Hospital Affiliated to Nanchang University, Nanchang, P.R. China
| |
Collapse
|
8
|
Artimani T, Najafi R. APPL1 as an important regulator of insulin and adiponectin‐signaling pathways in the PCOS: A narrative review. Cell Biol Int 2020; 44:1577-1587. [DOI: 10.1002/cbin.11367] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/09/2020] [Accepted: 04/25/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Tayebe Artimani
- Endometrium and Endometriosis Research CenterHamadan University of Medical Sciences Hamadan Iran
| | - Rezvan Najafi
- Research Center for Molecular MedicineHamadan University of Medical Sciences Hamadan Iran
| |
Collapse
|
9
|
Batty MB, Schittenhelm RB, Dorin-Semblat D, Doerig C, Garcia-Bustos JF. Interaction of Plasmodium falciparum casein kinase 1 with components of host cell protein trafficking machinery. IUBMB Life 2020; 72:1243-1249. [PMID: 32356940 DOI: 10.1002/iub.2294] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 03/25/2020] [Accepted: 04/09/2020] [Indexed: 12/21/2022]
Abstract
A pool of Plasmodium falciparum casein kinase 1 (PfCK1) has been shown to localize to the host red blood cell (RBC) membrane and be secreted to the extracellular medium during trophozoite stage of development. We attempted to identify mechanisms for secretion of PfCK1 and its appearance on the RBC membrane. We found that two host proteins with established functions in membrane trafficking in higher eukaryotes, GTPase-activating protein and Vps9 domain-containing protein 1 (GAPVD1), and Sorting nexin 22, consistently co-purify with PfCK1, suggesting that the parasite utilizes trafficking pathways previously thought to be inactive in RBCs. Furthermore, reciprocal immunoprecipitation experiments with GAPVD1 identified parasite proteins suggestive of a protein recycling pathway hitherto only described in higher eukaryotes. Thus, we have identified components of a trafficking pathway involving parasite proteins that act in concert with host proteins, and which we hypothesize mediates trafficking of PfCK1 to the RBC during infection.
Collapse
Affiliation(s)
- Mitchell B Batty
- Infection and Immunity Program and Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Ralf B Schittenhelm
- Monash Proteomics & Metabolomics Facility, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Dominique Dorin-Semblat
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, INSERM, Paris, France.,Institut National de la Transfusion Sanguine, Paris, France
| | - Christian Doerig
- Infection and Immunity Program and Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.,Centre for Chronic, Inflammatory and Infectious Diseases, School of Health and Biomedical Sciences, RMIT University, Bundoora, Victoria, Australia
| | - Jose F Garcia-Bustos
- Infection and Immunity Program and Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| |
Collapse
|
10
|
Duong KHM, Chun KH. Regulation of glucose transport by RhoA in 3T3-L1 adipocytes and L6 myoblasts. Biochem Biophys Res Commun 2019; 519:880-886. [PMID: 31561853 DOI: 10.1016/j.bbrc.2019.09.083] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 09/19/2019] [Indexed: 12/12/2022]
Abstract
RhoA is a key player in actin cytoskeleton reorganization and exerts most of its effect through the RhoA-ROCKs signaling pathway. Although recent studies have stressed the roles of ROCKs as regulators of glucose metabolism, little is known of the roles played by RhoA, the upstream regulators of ROCKs and other isotypes of Rho small-GTPases. This study was undertaken to determine whether Rho isotypes modulate glucose transport and insulin signaling in insulin-sensitive cell models, that is, 3T3-L1 adipocytes and L6 myoblasts. Glucose uptake assays showed that RhoA knockdown using siRNA reduced insulin-stimulated glucose transport in both cell types, whereas knockdown of RhoB or RhoC did not. Furthermore, RhoA overexpression increased insulin-stimulated glucose transport. Interestingly, the insulin-stimulated PI3K-Akt signaling pathway was unaffected under RhoA-depleted or -overexpressed conditions, which suggested RhoA might regulate glucose transport via an Akt-independent pathway. Interestingly, an immunoblot assay of signaling molecules related to actin-myosin cytoskeletal remodeling showed that unlike RhoA or RhoC, RhoA regulated ERM phosphorylation. Our results suggest that RhoA, but not RhoB or RhoC, mediates glucose transport by regulating the vesicle trafficking machinery in an Akt-independent manner.
Collapse
Affiliation(s)
- Khue Ha Minh Duong
- Gachon Institute of Pharmaceutical Sciences, College of Pharmacy, Gachon University, Incheon 21936, Republic of Korea
| | - Kwang-Hoon Chun
- Gachon Institute of Pharmaceutical Sciences, College of Pharmacy, Gachon University, Incheon 21936, Republic of Korea.
| |
Collapse
|
11
|
Akt is a critical node of acute myocardial insulin resistance and cardiac dysfunction after cardiopulmonary bypass. Life Sci 2019; 234:116734. [PMID: 31394126 DOI: 10.1016/j.lfs.2019.116734] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 08/04/2019] [Accepted: 08/04/2019] [Indexed: 10/26/2022]
Abstract
AIMS Acute myocardial insulin resistance is an independent risk factor for patients who undergo cardiac surgery with cardiopulmonary bypass (CPB). However, the underlying mechanism of insulin resistance during CPB has not been fully investigated. MATERIALS AND METHODS To explore the role of myocardial insulin resistance on the cardiac function and its underlying mechanism, CPB operation and pharmacological intervention were applied in mini pigs, and myocardial insulin signaling, glucose uptake, ATP production and cardiac function were examined. KEY FINDINGS Our data showed that CPB elicited not only hyperglycemia and hyperinsulinemia, but also inactivated Akt, and impaired the transposition of membrane glucose transporter-4 (GLUT-4), reduced glucose uptake and ATP production in the myocardium as well, which in turn was accompanied with cardiac dysfunction. Meanwhile, linear correlations were established among reduced myocardial glucose uptake, ATP production, and depressed cardiac systolic or diastolic function. Reactivation of Akt by SC79, an Akt agonist, partially alleviated myocardial insulin resistance and restored post CPB cardiac function via augmenting myocardial glucose uptake and ATP production. SIGNIFICANCE These findings revealed that acute myocardial insulin resistance due to inactivation of Akt played a key role in cardiac dysfunction post CPB via suppressing glucose metabolism related energy supply.
Collapse
|
12
|
Suzuki M, Chen HJ, Tomonaga S, Hashimoto O, Kawada T, Matsui T, Funaba M. Chronic retinoic acid treatment induces differentiation and changes in the metabolite levels of brown (pre)adipocytes. Cell Biochem Funct 2019; 37:377-384. [PMID: 31215681 DOI: 10.1002/cbf.3416] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 04/11/2019] [Accepted: 05/08/2019] [Indexed: 12/19/2022]
Abstract
Dietary vitamin A status affects energy metabolism. The present study explored the effect of all-trans retinoic acid (ATRA) on the expression levels of molecules and metabolites of brown adipocytes. Chronic ATRA treatment was initiated during the early stage (days 0-8) or late stage (days 8-12) of adipogenesis. Treatment with ATRA during the early and late stage of adipogenesis resulted in an increase in the expression level of Ucp1 and Cidea, genes highly expressed in brown adipocytes, on day 8 and day 12, respectively, whereas expression of Pgc-1α, another gene expressed during brown adipogenesis, was unaffected by ATRA. Non-targeted metabolomic analyses indicated that the pathways related to the glucose metabolism were affected by ATRA, irrespective of the differentiation stage. Cellular levels of glucose 6-phosphate, fructose 6-phosphate, citric acid, and succinic acid decreased after ATRA treatment on days 8 and 12. In contrast, glucose level was higher in ATRA-treated cells on day 8, but it was lower on day 12. ATRA decreased the cellular level of aconitic acid, fumaric acid, and malic acid on day 12 but not on day 8. Furthermore, ATRA increased the expression level of Hxk2 and downregulated the expressions of G6pdh and Pfkl/Pfkp on day 8 but not on day 12. Together, the results indicate that the chronic treatment with ATRA stimulated the formation of activated brown adipocytes, eventually leading to alterations in the levels of cellular metabolites related to glucose metabolism. SIGNIFICANCE OF THE STUDY: Significance of the study treatment with all-trans retinoic acid (ATRA) during the early and late stage of adipogenesis increased the expression of Ucp1 and Cidea, genes highly expressed in brown adipocytes, on day 8 and day 12. Cellular levels of glucose 6-phosphate, fructose 6-phosphate, citric acid, and succinic acid decreased after ATRA treatment on days 8 and 12. In contrast, glucose level was higher in ATRA-treated cells on day 8, but it was lower on day 12. The present results indicate that ATRA stimulated the formation of activated brown adipocytes, eventually leading to alterations in the levels of cellular metabolites related to glucose metabolism.
Collapse
Affiliation(s)
- Mika Suzuki
- Division of Applied Biosciences, Kyoto University Graduate School of Agriculture, Kyoto, Japan
| | - Hsuan-Ju Chen
- Division of Applied Biosciences, Kyoto University Graduate School of Agriculture, Kyoto, Japan
| | - Shozo Tomonaga
- Division of Applied Biosciences, Kyoto University Graduate School of Agriculture, Kyoto, Japan
| | - Osamu Hashimoto
- Laboratory of Experimental Animal Science, Kitasato University School of Veterinary Medicine, Towada, Japan
| | - Teruo Kawada
- Division of Food Science and Biotechnology, Kyoto University Graduate School of Agriculture, Kyoto, Japan
| | - Tohru Matsui
- Division of Applied Biosciences, Kyoto University Graduate School of Agriculture, Kyoto, Japan
| | - Masayuki Funaba
- Division of Applied Biosciences, Kyoto University Graduate School of Agriculture, Kyoto, Japan
| |
Collapse
|
13
|
Møller LLV, Klip A, Sylow L. Rho GTPases-Emerging Regulators of Glucose Homeostasis and Metabolic Health. Cells 2019; 8:E434. [PMID: 31075957 PMCID: PMC6562660 DOI: 10.3390/cells8050434] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/02/2019] [Accepted: 05/06/2019] [Indexed: 12/11/2022] Open
Abstract
Rho guanosine triphosphatases (GTPases) are key regulators in a number of cellular functions, including actin cytoskeleton remodeling and vesicle traffic. Traditionally, Rho GTPases are studied because of their function in cell migration and cancer, while their roles in metabolism are less documented. However, emerging evidence implicates Rho GTPases as regulators of processes of crucial importance for maintaining metabolic homeostasis. Thus, the time is now ripe for reviewing Rho GTPases in the context of metabolic health. Rho GTPase-mediated key processes include the release of insulin from pancreatic β cells, glucose uptake into skeletal muscle and adipose tissue, and muscle mass regulation. Through the current review, we cast light on the important roles of Rho GTPases in skeletal muscle, adipose tissue, and the pancreas and discuss the proposed mechanisms by which Rho GTPases act to regulate glucose metabolism in health and disease. We also describe challenges and goals for future research.
Collapse
Affiliation(s)
- Lisbeth Liliendal Valbjørn Møller
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, 2100 Copenhagen Oe, Denmark.
| | - Amira Klip
- Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada.
| | - Lykke Sylow
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, 2100 Copenhagen Oe, Denmark.
| |
Collapse
|
14
|
Rashid CS, Bansal A, Simmons RA. Oxidative Stress, Intrauterine Growth Restriction, and Developmental Programming of Type 2 Diabetes. Physiology (Bethesda) 2019; 33:348-359. [PMID: 30109821 DOI: 10.1152/physiol.00023.2018] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Intrauterine growth restriction (IUGR) leads to reduced birth weight and the development of metabolic diseases such as Type 2 diabetes in adulthood. Mitochondria dysfunction and oxidative stress are commonly found in key tissues (pancreatic islets, liver, and skeletal muscle) of IUGR individuals. In this review, we explore the role of oxidative stress in IUGR-associated diabetes etiology.
Collapse
Affiliation(s)
- Cetewayo S Rashid
- Center for Research on Reproduction and Women's Health, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
| | - Amita Bansal
- Center for Research on Reproduction and Women's Health, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
| | - Rebecca A Simmons
- Center for Research on Reproduction and Women's Health, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
| |
Collapse
|
15
|
Tsuchiya M, Sekiai S, Hatakeyama H, Koide M, Chaweewannakorn C, Yaoita F, Tan-No K, Sasaki K, Watanabe M, Sugawara S, Endo Y, Itoi E, Hagiwara Y, Kanzaki M. Neutrophils Provide a Favorable IL-1-Mediated Immunometabolic Niche that Primes GLUT4 Translocation and Performance in Skeletal Muscles. Cell Rep 2018; 23:2354-2364. [DOI: 10.1016/j.celrep.2018.04.067] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 03/09/2018] [Accepted: 04/14/2018] [Indexed: 11/27/2022] Open
|
16
|
Hu F, Li N, Li Z, Zhang C, Yue Y, Liu Q, Chen L, Bilan PJ, Niu W. Electrical pulse stimulation induces GLUT4 translocation in a Rac-Akt-dependent manner in C2C12 myotubes. FEBS Lett 2018; 592:644-654. [PMID: 29355935 DOI: 10.1002/1873-3468.12982] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 01/07/2018] [Accepted: 01/15/2018] [Indexed: 12/12/2022]
Abstract
Muscle contraction increases skeletal muscle glucose uptake, but the underlying mechanisms are not fully elucidated. While important for insulin-stimulated glucose uptake, the role of Akt in contraction-stimulated muscle glucose uptake is controversial. In our study, C2C12 skeletal muscle myotubes were contracted by electrical pulse stimulation (EPS). We found that EPS leads to Akt phosphorylation on sites S473 and T308 in a time-dependent manner. The Akt inhibitor MK2206 partly reduces EPS-stimulated GLUT4 translocation without affecting EPS-stimulated AMPK phosphorylation. EPS activates Rac1 GTP-binding, and EPS-stimulated GLUT4 translocation is partly inhibited by Rac1 inhibitor II and siRac1. Interestingly, both Rac1 inhibitor II and siRac1 inhibit EPS-stimulated Akt phosphorylation on sites S473 and T308. Our findings implicate a Rac1-Akt signaling pathway in EPS-stimulated GLUT4 translocation in C2C12 myotubes.
Collapse
Affiliation(s)
- Fang Hu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Nana Li
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Zhu Li
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Chang Zhang
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Yingying Yue
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Qian Liu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Liming Chen
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Philip J Bilan
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Wenyan Niu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| |
Collapse
|
17
|
da Silva Teixeira S, Filgueira C, Sieglaff DH, Benod C, Villagomez R, Minze LJ, Zhang A, Webb P, Nunes MT. 3,5-diiodothyronine (3,5-T2) reduces blood glucose independently of insulin sensitization in obese mice. Acta Physiol (Oxf) 2017; 220:238-250. [PMID: 27770485 DOI: 10.1111/apha.12821] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 05/30/2016] [Accepted: 10/14/2016] [Indexed: 02/06/2023]
Abstract
AIM Thyroid hormones regulate metabolic response. While triiodothyronine (T3) is usually considered to be the active form of thyroid hormone, one form of diiodothyronine (3,5-T2) exerts T3-like effects on energy consumption and lipid metabolism. 3,5-T2 also improves glucose tolerance in rats and 3,5-T2 levels correlate with fasting glucose in humans. Presently, however, little is known about mechanisms of 3,5-T2 effects on glucose metabolism. Here, we set out to compare effects of T3, 3,5-T2 and another form of T2 (3,3-T2) in a mouse model of diet-induced obesity and determined effects of T3 and 3,5-T2 on markers of classical insulin sensitization to understand how diiodothyronines influence blood glucose. METHODS Cell- and protein-based assays of thyroid hormone action. Assays of metabolic parameters in mice. Analysis of transcript and protein levels in different tissues by qRT-PCR and Western blot. RESULTS T3 and 3,5-T2 both reduce body weight, adiposity and body temperature despite increased food intake. 3,3'-T2 lacks these effects. T3 and 3,5-T2 reduce blood glucose levels, whereas 3,3'-T2 worsens glucose tolerance. Neither T3 nor 3,5-T2 affects markers of insulin sensitization in skeletal muscle or white adipose tissue (WAT), but both reduce hepatic GLUT2 glucose transporter levels and glucose output. T3 and 3,5-T2 also induce expression of mitochondrial uncoupling proteins (UCPs) 3 and 1 in skeletal muscle and WAT respectively. CONCLUSIONS 3,5-T2 influences glucose metabolism in a manner that is distinct from insulin sensitization and involves reductions in hepatic glucose output and changes in energy utilization.
Collapse
Affiliation(s)
- S. da Silva Teixeira
- Departamento de Fisiologia e Biofísica; Instituto de Ciências Biomédicas; Universidade de São Paulo; São Paulo Brazil
- Genomic Medicine; Houston Methodist Research Institute; Houston TX USA
| | - C. Filgueira
- Genomic Medicine; Houston Methodist Research Institute; Houston TX USA
| | - D. H. Sieglaff
- Genomic Medicine; Houston Methodist Research Institute; Houston TX USA
| | - C. Benod
- Genomic Medicine; Houston Methodist Research Institute; Houston TX USA
| | - R. Villagomez
- Genomic Medicine; Houston Methodist Research Institute; Houston TX USA
| | - L. J. Minze
- Genomic Medicine; Houston Methodist Research Institute; Houston TX USA
| | - A. Zhang
- Genomic Medicine; Houston Methodist Research Institute; Houston TX USA
| | - P. Webb
- Genomic Medicine; Houston Methodist Research Institute; Houston TX USA
| | - M. T. Nunes
- Departamento de Fisiologia e Biofísica; Instituto de Ciências Biomédicas; Universidade de São Paulo; São Paulo Brazil
| |
Collapse
|
18
|
Uhm M, Bazuine M, Zhao P, Chiang SH, Xiong T, Karunanithi S, Chang L, Saltiel AR. Phosphorylation of the exocyst protein Exo84 by TBK1 promotes insulin-stimulated GLUT4 trafficking. Sci Signal 2017; 10:10/471/eaah5085. [PMID: 28325821 DOI: 10.1126/scisignal.aah5085] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Insulin stimulates glucose uptake through the translocation of the glucose transporter GLUT4 to the plasma membrane. The exocyst complex tethers GLUT4-containing vesicles to the plasma membrane, a process that requires the binding of the G protein (heterotrimeric guanine nucleotide-binding protein) RalA to the exocyst complex. We report that upon activation of RalA, the protein kinase TBK1 phosphorylated the exocyst subunit Exo84. Knockdown of TBK1 blocked insulin-stimulated glucose uptake and GLUT4 translocation; knockout of TBK1 in adipocytes blocked insulin-stimulated glucose uptake; and ectopic overexpression of a kinase-inactive mutant of TBK1 reduced insulin-stimulated glucose uptake in 3T3-L1 adipocytes. The phosphorylation of Exo84 by TBK1 reduced its affinity for RalA and enabled its release from the exocyst. Overexpression of a kinase-inactive mutant of TBK1 blocked the dissociation of the TBK1/RalA/exocyst complex, and treatment of 3T3-L1 adipocytes with specific inhibitors of TBK1 reduced the rate of complex dissociation. Introduction of phosphorylation-mimicking or nonphosphorylatable mutant forms of Exo84 blocked insulin-stimulated GLUT4 translocation. Thus, these data indicate that TBK1 controls GLUT4 vesicle engagement and disengagement from the exocyst, suggesting that exocyst components not only constitute a tethering complex for the GLUT4 vesicle but also act as "gatekeepers" controlling vesicle fusion at the plasma membrane.
Collapse
Affiliation(s)
- Maeran Uhm
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA.,Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA.,Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Merlijn Bazuine
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Peng Zhao
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA.,Institute for Diabetes and Metabolic Health, Departments of Medicine and Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Shian-Huey Chiang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Tingting Xiong
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Louise Chang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alan R Saltiel
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA. .,Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA.,Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.,Institute for Diabetes and Metabolic Health, Departments of Medicine and Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| |
Collapse
|
19
|
Rab14 Act as Oncogene and Induce Proliferation of Gastric Cancer Cells via AKT Signaling Pathway. PLoS One 2017; 12:e0170620. [PMID: 28107526 PMCID: PMC5249107 DOI: 10.1371/journal.pone.0170620] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 01/06/2017] [Indexed: 01/08/2023] Open
Abstract
Rab14 is a member of RAS oncogene family, and its dysfunction has been reported to be involved in various types of human cancer. However, its expression and function were still unclear in gastric cancer. The aim of this study was to investigate the function and mechanism of Rab14 in gastric cancer cell lines. Quantitative real-time PCR (qRT-PCR) was performed in 17 gastric adenocarcinoma tissues and 4 cell lines to detect the expression of Rab14. 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT), colony formation and flow cytometry assays were employed to determine the proliferative ability, cell cycle transition and apoptosis in vitro in BGC-823 or SGC-7901 cells. Western blot was performed to investigate the pathways and mechanism of Rab14 regulation. In this study, we show that Rab14 presents a significant up-regulated expression among the paired tissue samples and cell lines in gastric cancer. When we overexpressed Rab14 in SGC-7901 cells or silenced Rab14 in BGC-823 cells, we found that Rab14 could modify cell growth, cell cycle or apoptosis, which accompanied with an obvious regulation of CCND1, CDK2 and BAX involving in AKT signaling pathway. In conclusion, this study provides a new evidence on that Rab14 functions as a novel tumor oncogene and could be a potential therapeutic target in gastric cancer.
Collapse
|
20
|
Al-Zoairy R, Pedrini MT, Khan MI, Engl J, Tschoner A, Ebenbichler C, Gstraunthaler G, Salzmann K, Bakry R, Niederwanger A. Serotonin improves glucose metabolism by Serotonylation of the small GTPase Rab4 in L6 skeletal muscle cells. Diabetol Metab Syndr 2017; 9:1. [PMID: 28053672 PMCID: PMC5209910 DOI: 10.1186/s13098-016-0201-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 12/10/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Serotonin (5-HT) improves insulin sensitivity and glucose metabolism, however, the underlying molecular mechanism has remained elusive. Previous studies suggest that 5-HT can activate intracellular small GTPases directly by covalent binding, a process termed serotonylation. Activated small GTPases have been associated with increased GLUT4 translocation to the cell membrane. Therefore, we investigated whether serotonylation of small GTPases may be involved in improving Insulin sensitivity and glucose metabolism. METHODS Using fully differentiated L6 rat skeletal muscle cells, we studied the effect of 5-HT in the absence or presence of insulin on glycogen synthesis, glucose uptake and GLUT4 translocation. To prove our L6 model we additionally performed preliminary experiments in C2C12 murine skeletal muscle cells. RESULTS Incubation with 5-HT led to an increase in deoxyglucose uptake in a concentration-dependent fashion. Accordingly, GLUT4 translocation to the cell membrane and glycogen content were increased. These effects of 5-HT on Glucose metabolism could be augmented by co-incubation with insulin and blunted by co incubation of 5-HT with monodansylcadaverine, an inhibitor of protein serotonylation. In accordance with this observation, incubation with 5-HT resulted in serotonylation of a protein with a molecular weight of approximately 25 kDa. We identified this protein as the small GTPase Rab4, the activity of which has been shown to be stimulated by both insulin signalling and serotonylation. CONCLUSION Our data suggest that 5-HT elicits its beneficial effects on Glucose metabolism through serotonylation of Rab4, which likely represents the converging point between the insulin and the 5-HT signalling cascades.
Collapse
Affiliation(s)
- Ramona Al-Zoairy
- Department of Internal Medicine I, Medical University of Innsbruck, Innsbruck, Austria
| | - Michael T. Pedrini
- Department of Internal Medicine I, Medical University of Innsbruck, Innsbruck, Austria
| | - Mohammad Imran Khan
- Department of Internal Medicine I, Medical University of Innsbruck, Innsbruck, Austria
| | - Julia Engl
- Department of Internal Medicine I, Medical University of Innsbruck, Innsbruck, Austria
| | - Alexander Tschoner
- Department of Internal Medicine I, Medical University of Innsbruck, Innsbruck, Austria
| | - Christoph Ebenbichler
- Department of Internal Medicine I, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Karin Salzmann
- Department of Internal Medicine I, Medical University of Innsbruck, Innsbruck, Austria
| | - Rania Bakry
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University Innsbruck, Innsbruck, Austria
| | - Andreas Niederwanger
- Department of Internal Medicine I, Medical University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
21
|
Abstract
Heart failure is associated with generalized insulin resistance. Moreover, insulin-resistant states such as type 2 diabetes mellitus and obesity increases the risk of heart failure even after adjusting for traditional risk factors. Insulin resistance or type 2 diabetes mellitus alters the systemic and neurohumoral milieu, leading to changes in metabolism and signaling pathways in the heart that may contribute to myocardial dysfunction. In addition, changes in insulin signaling within cardiomyocytes develop in the failing heart. The changes range from activation of proximal insulin signaling pathways that may contribute to adverse left ventricular remodeling and mitochondrial dysfunction to repression of distal elements of insulin signaling pathways such as forkhead box O transcriptional signaling or glucose transport, which may also impair cardiac metabolism, structure, and function. This article will review the complexities of insulin signaling within the myocardium and ways in which these pathways are altered in heart failure or in conditions associated with generalized insulin resistance. The implications of these changes for therapeutic approaches to treating or preventing heart failure will be discussed.
Collapse
Affiliation(s)
- Christian Riehle
- From the Division of Endocrinology and Metabolism, Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City
| | - E Dale Abel
- From the Division of Endocrinology and Metabolism, Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City.
| |
Collapse
|
22
|
Sun Y, Côté JF, Du K. Elmo2 Is a Regulator of Insulin-dependent Glut4 Membrane Translocation. J Biol Chem 2016; 291:16150-61. [PMID: 27226625 DOI: 10.1074/jbc.m116.731521] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Indexed: 11/06/2022] Open
Abstract
Elmo2, a member of the Elmo protein family, has been implicated in the regulation of Rac1 and Akt activation. Recently, we found that Elmo2 specifically interacts with ClipR-59. Because Akt and Rac1 have been implicated in insulin dependent Glut4 membrane translocation, we hypothesize here that Elmo2 may play a role in insulin-dependent Glut4 membrane translocation. Accordingly, we found that overexpression of Elmo2 enhanced, whereas its knockdown suppressed, insulin-dependent Glut4 membrane translocation in both 3T3-L1 adipocytes and L6 skeletal muscle cells. We also examined whether Elmo2 contributes to the insulin-mediated activation of Rac1 and Akt. We found that Elmo2 is required for insulin-induced Rac1 GTP loading, but not AKT activation, in L6 cells induced by insulin. Instead, Elmo2 is required to promote the insulin-induced membrane association of Akt. Together, our studies demonstrate that Elmo2 is a new regulator of insulin-dependent Glut4 membrane translocation through modulating Rac1 activity and Akt membrane compartmentalization.
Collapse
Affiliation(s)
- Yingmin Sun
- From the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111 and
| | - Jean-François Côté
- the Institut de Recherches Cliniques de Montréal, Université de Montréal, Montréal, Québec H2W 1R7, Canada
| | - Keyong Du
- From the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111 and
| |
Collapse
|
23
|
Diabetes Alters the Expression and Translocation of the Insulin-Sensitive Glucose Transporters 4 and 8 in the Atria. PLoS One 2015; 10:e0146033. [PMID: 26720696 PMCID: PMC4697822 DOI: 10.1371/journal.pone.0146033] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 12/12/2015] [Indexed: 01/14/2023] Open
Abstract
Although diabetes has been identified as a major risk factor for atrial fibrillation, little is known about glucose metabolism in the healthy and diabetic atria. Glucose transport into the cell, the rate-limiting step of glucose utilization, is regulated by the Glucose Transporters (GLUTs). Although GLUT4 is the major isoform in the heart, GLUT8 has recently emerged as a novel cardiac isoform. We hypothesized that GLUT-4 and -8 translocation to the atrial cell surface will be regulated by insulin and impaired during insulin-dependent diabetes. GLUT protein content was measured by Western blotting in healthy cardiac myocytes and type 1 (streptozotocin-induced, T1Dx) diabetic rodents. Active cell surface GLUT content was measured using a biotinylated photolabeled assay in the perfused heart. In the healthy atria, insulin stimulation increased both GLUT-4 and -8 translocation to the cell surface (by 100% and 240%, respectively, P<0.05). Upon insulin stimulation, we reported an increase in Akt (Th308 and s473 sites) and AS160 phosphorylation, which was positively (P<0.05) correlated with GLUT4 protein content in the healthy atria. During diabetes, active cell surface GLUT-4 and -8 content was downregulated in the atria (by 70% and 90%, respectively, P<0.05). Akt and AS160 phosphorylation was not impaired in the diabetic atria, suggesting the presence of an intact insulin signaling pathway. This was confirmed by the rescued translocation of GLUT-4 and -8 to the atrial cell surface upon insulin stimulation in the atria of type 1 diabetic subjects. In conclusion, our data suggest that: 1) both GLUT-4 and -8 are insulin-sensitive in the healthy atria through an Akt/AS160 dependent pathway; 2) GLUT-4 and -8 trafficking is impaired in the diabetic atria and rescued by insulin treatment. Alterations in atrial glucose transport may induce perturbations in energy production, which may provide a metabolic substrate for atrial fibrillation during diabetes.
Collapse
|
24
|
Tsuchiya A, Kanno T, Shimizu T, Tanaka A, Nishizaki T. Rac1 and ROCK are implicated in the cell surface delivery of GLUT4 under the control of the insulin signal mimetic diDCP-LA-PE. J Pharmacol Sci 2015; 128:179-84. [PMID: 26238253 DOI: 10.1016/j.jphs.2015.07.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 04/27/2015] [Accepted: 07/02/2015] [Indexed: 12/16/2022] Open
Abstract
The phosphatidylethanolamine derivative 1,2-O-bis-[8-{2-(2-pentyl-cyclopropylmethyl)-cyclopropyl}-octanoyl]-sn-glycero-3-phosphatidylethanolamine (diDCP-LA-PE) promoted GLUT4 translocation to the cell surface in differentiated 3T3-L1-GLUT4myc adipocytes through a pathway along a phosphatidylinositol 3-kinase (PI3K)/3-phosphoinositide-dependent protein kinase-1 (PDK1)/Akt axis, that mimics insulin signaling. Moreover, diDCP-LA-PE-induced GLUT4 translocation was suppressed by inhibitors of the Rho GTPase Rac1 and Rho-associated coiled-coil-containing protein kinase (ROCK) or knocking-down Rac1 and ROCK1. The results of the present study show that Rac1 and ROCK are critical for regulation of GLUT4 trafficking by diDCP-LA-PE as well as insulin.
Collapse
Affiliation(s)
- Ayako Tsuchiya
- Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Takeshi Kanno
- Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Tadashi Shimizu
- Laboratory of Chemical Biology, Advanced Medicinal Research Center, Hyogo University of Health Sciences, Kobe, Japan
| | - Akito Tanaka
- Laboratory of Chemical Biology, Advanced Medicinal Research Center, Hyogo University of Health Sciences, Kobe, Japan
| | - Tomoyuki Nishizaki
- Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, Nishinomiya, Japan.
| |
Collapse
|
25
|
Chua CEL, Tang BL. Role of Rab GTPases and their interacting proteins in mediating metabolic signalling and regulation. Cell Mol Life Sci 2015; 72:2289-304. [PMID: 25690707 PMCID: PMC11113524 DOI: 10.1007/s00018-015-1862-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 02/09/2015] [Accepted: 02/11/2015] [Indexed: 10/24/2022]
Abstract
The vesicular transport pathways, which shuttle materials to and from the cell surface and within the cell, and the metabolic (growth factor and nutrient) signalling pathways, which integrate a variety of extracellular and intracellular signals to mediate growth, proliferation or survival, are both important for cellular physiology. There is evidence to suggest that the transport and metabolic signalling pathways intersect-vesicular transport can affect the regulation of metabolic signals and vice versa. The Rab family GTPases regulate the specificity of vesicular transport steps in the cell. Together with their interacting proteins, Rabs would likely constitute the points of intersection between vesicular transport and metabolic signalling pathways. Examples of these points would include growth factor signalling, glucose and lipid metabolism, as well as autophagy. Many of these processes involve mechanistic/mammalian target of rapamycin (mTOR) complex 1 (mTORC1) in downstream cascades, or are regulated by TORC signalling. A general functionality of the vesicular transport processes controlled by the Rabs is also important for spatial and temporal regulation of the transmission of metabolic signals between the cell surface and the nucleus. In other cases, specific Rabs and their interacting proteins are known to function in recruiting metabolism-related proteins to target membranes, or may compete with other factors in the TORC signalling pathway as a means of metabolic regulation. We review and discuss herein examples of how Rabs and their interacting proteins can mediate metabolic signalling and regulation in cells.
Collapse
Affiliation(s)
- Christelle En Lin Chua
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University Health System, 8 Medical Drive, Singapore, 117597, Singapore,
| | | |
Collapse
|
26
|
A New Member of the TBC1D15 Family from Chiloscyllium plagiosum: Rab GTPase-Activating Protein Based on Rab7 as a Substrate. Mar Drugs 2015; 13:2955-66. [PMID: 25984991 PMCID: PMC4446614 DOI: 10.3390/md13052955] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Revised: 04/28/2015] [Accepted: 05/05/2015] [Indexed: 02/07/2023] Open
Abstract
APSL (active peptide from shark liver) is a hepatic stimulator cytokine from the liver of Chiloscyllium. It can effectively protect islet cells and improve complications in mice with alloxan-induced diabetes. Here, we demonstrate that the APSL sequence is present in the N-terminus of novel TBC (Tre-2, Bub2 and Cdc16) domain family, member 15 (TBC1D15) from Chiloscylliumplagiosum. This shark TBC1D15 gene, which contains an ORF of 2088 bp, was identified from a cDNA library of regenerating shark liver. Bioinformatic analysis showed that the gene is highly homologous to TBC1D15 genes from other species. Moreover, the N-terminus of shark TBC1D15 contains a motif of unknown function (DUF3548), which encompasses the APSL fragment. Rab-GAP activity analysis showed that shark TBC1D15 is a new member of the TBC1D15 family. These results demonstrated that shark TBC1D15 possesses Rab-GAP activity using Rab7 as a substrate, which is a common property of the TBC1D15 family. The involvement of APSL at the N-terminus of TBC1D15 also demonstrates that this protein might be involved in insulin signaling and may be associated with the development of type 2 diabetes. The current findings pave the way for further functional and clinical studies of these proteins from marine sources.
Collapse
|
27
|
Tumour-associated mutant p53 drives the Warburg effect. Nat Commun 2014; 4:2935. [PMID: 24343302 PMCID: PMC3969270 DOI: 10.1038/ncomms3935] [Citation(s) in RCA: 313] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 11/14/2013] [Indexed: 12/11/2022] Open
Abstract
Tumour cells primarily utilize aerobic glycolysis for energy production, a phenomenon known as the Warburg effect. Its mechanism is not well understood. The tumour suppressor gene p53 is frequently mutated in tumours. Many tumour-associated mutant p53 (mutp53) proteins not only lose tumour suppressive function but also gain new oncogenic functions that are independent of wild-type p53, defined as mutp53 gain of function (GOF). Here we show that tumour-associated mutp53 stimulates the Warburg effect in cultured cells and mutp53 knockin mice as a new mutp53 GOF. Mutp53 stimulates the Warburg effect through promoting GLUT1 translocation to the plasma membrane, which is mediated by activated RhoA and its downstream effector ROCK. Inhibition of RhoA/ROCK/GLUT1 signalling largely abolishes mutp53 GOF in stimulating the Warburg effect. Furthermore, inhibition of glycolysis in tumour cells greatly compromises mutp53 GOF in promoting tumorigenesis. Thus, our results reveal a new mutp53 GOF and a mechanism for controlling the Warburg effect.
Collapse
|
28
|
Pedraza CE, Taylor C, Pereira A, Seng M, Tham CS, Izrael M, Webb M. Induction of oligodendrocyte differentiation and in vitro myelination by inhibition of rho-associated kinase. ASN Neuro 2014; 6:6/4/1759091414538134. [PMID: 25289646 PMCID: PMC4189421 DOI: 10.1177/1759091414538134] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In inflammatory demyelinating diseases such as multiple sclerosis (MS), myelin
degradation results in loss of axonal function and eventual axonal degeneration.
Differentiation of resident oligodendrocyte precursor cells (OPCs) leading to
remyelination of denuded axons occurs regularly in early stages of MS but halts as
the pathology transitions into progressive MS. Pharmacological potentiation of
endogenous OPC maturation and remyelination is now recognized as a promising
therapeutic approach for MS. In this study, we analyzed the effects of modulating the
Rho-A/Rho-associated kinase (ROCK) signaling pathway, by the use of selective
inhibitors of ROCK, on the transformation of OPCs into mature, myelinating
oligodendrocytes. Here we demonstrate, with the use of cellular cultures from rodent
and human origin, that ROCK inhibition in OPCs results in a significant generation of
branches and cell processes in early differentiation stages, followed by accelerated
production of myelin protein as an indication of advanced maturation. Furthermore,
inhibition of ROCK enhanced myelin formation in cocultures of human OPCs and neurons
and remyelination in rat cerebellar tissue explants previously demyelinated with
lysolecithin. Our findings indicate that by direct inhibition of this signaling
molecule, the OPC differentiation program is activated resulting in morphological and
functional cell maturation, myelin formation, and regeneration. Altogether, we show
evidence of modulation of the Rho-A/ROCK signaling pathway as a viable target for the
induction of remyelination in demyelinating pathologies.
Collapse
Affiliation(s)
- Carlos E Pedraza
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | | | - Albertina Pereira
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | - Michelle Seng
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | - Chui-Se Tham
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | | | - Michael Webb
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| |
Collapse
|
29
|
Tsuchiya A, Kanno T, Nishizaki T. PI3 kinase directly phosphorylates Akt1/2 at Ser473/474 in the insulin signal transduction pathway. J Endocrinol 2014; 220:49-59. [PMID: 24169049 PMCID: PMC3842210 DOI: 10.1530/joe-13-0172] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Insulin stimulated translocation of the glucose transporter GLUT4 from the cytosol to the plasma membrane in a concentration (1 nM-1 μM)-dependent manner and increased glucose uptake in 3T3-L1 adipocytes. Insulin-induced GLUT4 translocation to the cell surface was prevented by the phosphoinositide 3 kinase (PI3K) inhibitor wortmannin, the 3-phosphoinositide-dependent protein kinase 1 (PDK1) inhibitor BX912 or the Akt1/2 inhibitor MK2206, and by knocking-down PI3K, PDK1 or Akt1/2. Insulin increased phosphorylation of Akt1/2 at Thr308/309 and Ser473/474, to activate Akt1/2, in the adipocytes. Insulin-induced phosphorylation of Akt1/2 was suppressed by wortmannin and knocking-down PI3K, while no significant inhibition of the phosphorylation was obtained with BX912 or knocking-down PDK1. In the cell-free Akt assay, PI3K phosphorylated Akt1 both at Thr308 and Ser473 and Akt2 at Ser474 alone. In contrast, PDK1 phosphorylates Akt1 at Thr308 and Akt2 at Thr309. The results of this study indicate that PI3K activates Akt1, independently of PDK1, and Akt2 by cooperating with PDK1 in the insulin signal transduction pathway linked to GLUT4 translocation.
Collapse
Affiliation(s)
| | | | - T Nishizaki
- Correspondence should be addressed to T Nishizaki;
| |
Collapse
|
30
|
Török Z, Crul T, Maresca B, Schütz GJ, Viana F, Dindia L, Piotto S, Brameshuber M, Balogh G, Péter M, Porta A, Trapani A, Gombos I, Glatz A, Gungor B, Peksel B, Vigh L, Csoboz B, Horváth I, Vijayan MM, Hooper PL, Harwood JL, Vigh L. Plasma membranes as heat stress sensors: from lipid-controlled molecular switches to therapeutic applications. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:1594-618. [PMID: 24374314 DOI: 10.1016/j.bbamem.2013.12.015] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 12/09/2013] [Accepted: 12/18/2013] [Indexed: 12/31/2022]
Abstract
The classic heat shock (stress) response (HSR) was originally attributed to protein denaturation. However, heat shock protein (Hsp) induction occurs in many circumstances where no protein denaturation is observed. Recently considerable evidence has been accumulated to the favor of the "Membrane Sensor Hypothesis" which predicts that the level of Hsps can be changed as a result of alterations to the plasma membrane. This is especially pertinent to mild heat shock, such as occurs in fever. In this condition the sensitivity of many transient receptor potential (TRP) channels is particularly notable. Small temperature stresses can modulate TRP gating significantly and this is influenced by lipids. In addition, stress hormones often modify plasma membrane structure and function and thus initiate a cascade of events, which may affect HSR. The major transactivator heat shock factor-1 integrates the signals originating from the plasma membrane and orchestrates the expression of individual heat shock genes. We describe how these observations can be tested at the molecular level, for example, with the use of membrane perturbers and through computational calculations. An important fact which now starts to be addressed is that membranes are not homogeneous nor do all cells react identically. Lipidomics and cell profiling are beginning to address the above two points. Finally, we observe that a deregulated HSR is found in a large number of important diseases where more detailed knowledge of the molecular mechanisms involved may offer timely opportunities for clinical interventions and new, innovative drug treatments. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
Collapse
Affiliation(s)
- Zsolt Török
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary.
| | - Tim Crul
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Bruno Maresca
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Salerno, Italy
| | - Gerhard J Schütz
- Institute of Applied Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10, 1040 Vienna, Austria
| | - Felix Viana
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, 03550 San Juan de Alicante, Spain
| | - Laura Dindia
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Stefano Piotto
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Salerno, Italy
| | - Mario Brameshuber
- Institute of Applied Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10, 1040 Vienna, Austria
| | - Gábor Balogh
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Mária Péter
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Amalia Porta
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Salerno, Italy
| | - Alfonso Trapani
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Salerno, Italy
| | - Imre Gombos
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Attila Glatz
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Burcin Gungor
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Begüm Peksel
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - László Vigh
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Bálint Csoboz
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Ibolya Horváth
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary
| | - Mathilakath M Vijayan
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada; Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Phillip L Hooper
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Medical School, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - John L Harwood
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, Wales, UK
| | - László Vigh
- Institute of Biochemistry, Biological Research Centre of the Hung. Acad. Sci., Szeged H-6726, Hungary.
| |
Collapse
|
31
|
Treebak JT, Pehmøller C, Kristensen JM, Kjøbsted R, Birk JB, Schjerling P, Richter EA, Goodyear LJ, Wojtaszewski JFP. Acute exercise and physiological insulin induce distinct phosphorylation signatures on TBC1D1 and TBC1D4 proteins in human skeletal muscle. J Physiol 2013; 592:351-75. [PMID: 24247980 DOI: 10.1113/jphysiol.2013.266338] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We investigated the phosphorylation signatures of two Rab-GTPase activating proteins TBC1D1 and TBC1D4 in human skeletal muscle in response to physical exercise and physiological insulin levels induced by a carbohydrate rich meal using a paired experimental design. Eight healthy male volunteers exercised in the fasted or fed state and muscle biopsies were taken before and immediately after exercise. We identified TBC1D1/4 phospho-sites that (1) did not respond to exercise or postprandial increase in insulin (TBC1D4: S666), (2) responded to insulin only (TBC1D4: S318), (3) responded to exercise only (TBC1D1: S237, S660, S700; TBC1D4: S588, S751), and (4) responded to both insulin and exercise (TBC1D1: T596; TBC1D4: S341, T642, S704). In the insulin-stimulated leg, Akt phosphorylation of both T308 and S473 correlated significantly with multiple sites on both TBC1D1 (T596) and TBC1D4 (S318, S341, S704). Interestingly, in the exercised leg in the fasted state TBC1D1 phosphorylation (S237, T596) correlated significantly with the activity of the α2/β2/γ3 AMPK trimer, whereas TBC1D4 phosphorylation (S341, S704) correlated with the activity of the α2/β2/γ1 AMPK trimer. Our data show differential phosphorylation of TBC1D1 and TBC1D4 in response to physiological stimuli in human skeletal muscle and support the idea that Akt and AMPK are upstream kinases. TBC1D1 phosphorylation signatures were comparable between in vitro contracted mouse skeletal muscle and exercised human muscle, and we show that AMPK regulated phosphorylation of these sites in mouse muscle. Contraction and exercise elicited a different phosphorylation pattern of TBC1D4 in mouse compared with human muscle, and although different circumstances in our experimental setup may contribute to this difference, the observation exemplifies that transferring findings between species is problematic.
Collapse
Affiliation(s)
- Jonas T Treebak
- The August Krogh Centre, Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Universitetsparken 13 DK-2100, Copenhagen, Denmark.
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Abstract
Glucose is an important fuel for contracting muscle, and normal glucose metabolism is vital for health. Glucose enters the muscle cell via facilitated diffusion through the GLUT4 glucose transporter which translocates from intracellular storage depots to the plasma membrane and T-tubules upon muscle contraction. Here we discuss the current understanding of how exercise-induced muscle glucose uptake is regulated. We briefly discuss the role of glucose supply and metabolism and concentrate on GLUT4 translocation and the molecular signaling that sets this in motion during muscle contractions. Contraction-induced molecular signaling is complex and involves a variety of signaling molecules including AMPK, Ca(2+), and NOS in the proximal part of the signaling cascade as well as GTPases, Rab, and SNARE proteins and cytoskeletal components in the distal part. While acute regulation of muscle glucose uptake relies on GLUT4 translocation, glucose uptake also depends on muscle GLUT4 expression which is increased following exercise. AMPK and CaMKII are key signaling kinases that appear to regulate GLUT4 expression via the HDAC4/5-MEF2 axis and MEF2-GEF interactions resulting in nuclear export of HDAC4/5 in turn leading to histone hyperacetylation on the GLUT4 promoter and increased GLUT4 transcription. Exercise training is the most potent stimulus to increase skeletal muscle GLUT4 expression, an effect that may partly contribute to improved insulin action and glucose disposal and enhanced muscle glycogen storage following exercise training in health and disease.
Collapse
Affiliation(s)
- Erik A Richter
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.
| | | |
Collapse
|
33
|
Tsuchiya A, Kanno T, Nishizaki T. Diacylglycerol promotes GLUT4 translocation to the cell surface in a PKCε-dependent and PKCλ/ι and -ζ-independent manner. Life Sci 2013; 93:240-6. [DOI: 10.1016/j.lfs.2013.06.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 06/04/2013] [Accepted: 06/11/2013] [Indexed: 10/26/2022]
|
34
|
Affiliation(s)
- Assaf Rudich
- Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Amira Klip
- Program in Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
- Corresponding author: Amira Klip,
| |
Collapse
|
35
|
Chiu TT, Sun Y, Koshkina A, Klip A. Rac-1 superactivation triggers insulin-independent glucose transporter 4 (GLUT4) translocation that bypasses signaling defects exerted by c-Jun N-terminal kinase (JNK)- and ceramide-induced insulin resistance. J Biol Chem 2013; 288:17520-31. [PMID: 23640896 DOI: 10.1074/jbc.m113.467647] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Insulin activates a cascade of signaling molecules, including Rac-1, Akt, and AS160, to promote the net gain of glucose transporter 4 (GLUT4) at the plasma membrane of muscle cells. Interestingly, constitutively active Rac-1 expression results in a hormone-independent increase in surface GLUT4; however, the molecular mechanism and significance behind this effect remain unresolved. Using L6 myoblasts stably expressing myc-tagged GLUT4, we found that overexpression of constitutively active but not wild-type Rac-1 sufficed to drive GLUT4 translocation to the membrane of comparable magnitude with that elicited by insulin. Stimulation of endogenous Rac-1 by Tiam1 overexpression elicited a similar hormone-independent gain in surface GLUT4. This effect on GLUT4 traffic could also be reproduced by acutely activating a Rac-1 construct via rapamycin-mediated heterodimerization. Strategies triggering Rac-1 "superactivation" (i.e. to levels above those attained by insulin alone) produced a modest gain in plasma membrane phosphatidylinositol 3,4,5-trisphosphate, moderate Akt activation, and substantial AS160 phosphorylation, which translated into GLUT4 translocation and negated the requirement for IRS-1. This unique signaling capacity exerted by Rac-1 superactivation bypassed the defects imposed by JNK- and ceramide-induced insulin resistance and allowed full and partial restoration of the GLUT4 translocation response, respectively. We propose that potent elevation of Rac-1 activation alone suffices to drive insulin-independent GLUT4 translocation in muscle cells, and such a strategy might be exploited to bypass signaling defects during insulin resistance.
Collapse
Affiliation(s)
- Tim Ting Chiu
- Program in Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | | | | | | |
Collapse
|
36
|
Reed SE, Hodgson LR, Song S, May MT, Kelly EE, McCaffrey MW, Mastick CC, Verkade P, Tavaré JM. A role for Rab14 in the endocytic trafficking of GLUT4 in 3T3-L1 adipocytes. J Cell Sci 2013; 126:1931-41. [PMID: 23444368 DOI: 10.1242/jcs.104307] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Insulin enhances the uptake of glucose into adipocytes and muscle cells by promoting the redistribution of the glucose transporter isoform 4 (GLUT4) from intracellular compartments to the cell surface. Rab GTPases regulate the trafficking itinerary of GLUT4 and several have been found on immunopurified GLUT4 vesicles. Specifically, Rab14 has previously been implicated in GLUT4 trafficking in muscle although its role, if any, in adipocytes is poorly understood. Analysis of 3T3-L1 adipocytes using confocal microscopy demonstrated that endogenous GLUT4 and endogenous Rab14 exhibited a partial colocalisation. However, when wild-type Rab14 or a constitutively-active Rab14Q70L mutant were overexpressed in these cells, the colocalisation with both GLUT4 and IRAP became extensive. Interestingly, this colocalisation was restricted to enlarged 'ring-like' vesicular structures (mean diameter 1.3 µm), which were observed in the presence of overexpressed wild-type Rab14 and Rab14Q70L, but not an inactive Rab14S25N mutant. These enlarged vesicles contained markers of early endosomes and were rapidly filled by GLUT4 and transferrin undergoing endocytosis from the plasma membrane. The Rab14Q70L mutant reduced basal and insulin-stimulated cell surface GLUT4 levels, probably by retaining GLUT4 in an insulin-insensitive early endosomal compartment. Furthermore, shRNA-mediated depletion of Rab14 inhibited the transit of GLUT4 through early endosomal compartments towards vesicles and tubules in the perinuclear region. Given the previously reported role of Rab14 in trafficking between endosomes and the Golgi complex, we propose that the primary role of Rab14 in GLUT4 trafficking is to control the transit of internalised GLUT4 from early endosomes into the Golgi complex, rather than direct GLUT4 translocation to the plasma membrane.
Collapse
Affiliation(s)
- Sam E Reed
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Zhu Y, Pereira RO, O'Neill BT, Riehle C, Ilkun O, Wende AR, Rawlings TA, Zhang YC, Zhang Q, Klip A, Shiojima I, Walsh K, Abel ED. Cardiac PI3K-Akt impairs insulin-stimulated glucose uptake independent of mTORC1 and GLUT4 translocation. Mol Endocrinol 2012. [PMID: 23204326 DOI: 10.1210/me.2012-1210] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Impaired insulin-mediated glucose uptake characterizes cardiac muscle in humans and animals with insulin resistance and diabetes, despite preserved or enhanced phosphatidylinositol 3-kinase (PI3K) and the serine-threonine kinase, Akt-signaling, via mechanisms that are incompletely understood. One potential mechanism is PI3K- and Akt-mediated activation of mechanistic target of rapamycin (mTOR) and ribosomal protein S6 kinase (S6K), which may impair insulin-mediated activation of insulin receptor substrate (IRS)1/2 via inhibitory serine phosphorylation or proteasomal degradation. To gain mechanistic insights by which constitutive activation of PI3K or Akt may desensitize insulin-mediated glucose uptake in cardiomyocytes, we examined mice with cardiomyocyte-restricted, constitutive or inducible overexpression of a constitutively activated PI3K or a myristoylated Akt1 (myrAkt1) transgene that also expressed a myc-epitope-tagged glucose transporter type 4 protein (GLUT4). Although short-term activation of PI3K and myrAkt1 increased mTOR and S6 signaling, there was no impairment in insulin-mediated activation of IRS1/2. However, insulin-mediated glucose uptake was reduced by 50-80%. Although longer-term activation of Akt reduced IRS2 protein content via an mTORC1-mediated mechanism, treatment of transgenic mice with rapamycin failed to restore insulin-mediated glucose uptake, despite restoring IRS2. Transgenic activation of Akt and insulin-stimulation of myrAkt1 transgenic cardiomyocytes increased sarcolemmal insertion of myc-GLUT4 to levels equivalent to that observed in insulin-stimulated wild-type controls. Despite preserved GLUT4 translocation, glucose uptake was not elevated by the presence of constitutive activation of PI3K and Akt. Hexokinase II activity was preserved in myrAkt1 hearts. Thus, constitutive activation of PI3K and Akt in cardiomyocytes impairs GLUT4-mediated glucose uptake via mechanisms that impair the function of GLUT4 after its plasma-membrane insertion.
Collapse
Affiliation(s)
- Yi Zhu
- Division of Endocrinology, Metabolism, and Diabetes and Program in Molecular Medicine, University of Utah, Salt Lake City, Utah 84112, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Aoyagi K, Ohara-Imaizumi M, Nishiwaki C, Nakamichi Y, Ueki K, Kadowaki T, Nagamatsu S. Acute inhibition of PI3K-PDK1-Akt pathway potentiates insulin secretion through upregulation of newcomer granule fusions in pancreatic β-cells. PLoS One 2012; 7:e47381. [PMID: 23077605 PMCID: PMC3471824 DOI: 10.1371/journal.pone.0047381] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 09/12/2012] [Indexed: 02/03/2023] Open
Abstract
In glucose-induced insulin secretion from pancreatic β-cells, a population of insulin granules fuses with the plasma membrane without the typical docking process (newcomer granule fusions), however, its mechanism is unclear. In this study, we investigated the PI3K signaling pathways involved in the upregulation of newcomer granule fusions. Acute treatment with the class IA-selective PI3K inhibitors, PIK-75 and PI-103, enhanced the glucose-induced insulin secretion. Total internal reflection fluorescent microscopy revealed that the PI3K inhibitors increased the fusion events from newcomer granules. We developed a new system for transfection into pancreatic islets and demonstrated the usefulness of this system in order for evaluating the effect of transfected genes on the glucose-induced secretion in primary cultured pancreatic islets. Using this transfection system together with a series of constitutive active mutants, we showed that the PI3K-3-phosphoinositide dependent kinase-1 (PDK1)-Akt pathway mediated the potentiation of insulin secretion. The Akt inhibitor also enhanced the glucose-induced insulin secretion in parallel with the upregulation of newcomer granule fusions, probably via increased motility of intracellular insulin granules. These data suggest that the PI3K-PDK1-Akt pathway plays a significant role in newcomer granule fusions, probably through an alteration of the dynamics of the intracellular insulin granules.
Collapse
Affiliation(s)
- Kyota Aoyagi
- Department of Biochemistry, Kyorin University School of Medicine, Tokyo, Japan
| | - Mica Ohara-Imaizumi
- Department of Biochemistry, Kyorin University School of Medicine, Tokyo, Japan
| | - Chiyono Nishiwaki
- Department of Biochemistry, Kyorin University School of Medicine, Tokyo, Japan
| | - Yoko Nakamichi
- Department of Biochemistry, Kyorin University School of Medicine, Tokyo, Japan
| | - Kohjiro Ueki
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Takashi Kadowaki
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Shinya Nagamatsu
- Department of Biochemistry, Kyorin University School of Medicine, Tokyo, Japan
- * E-mail:
| |
Collapse
|
39
|
Boguslavsky S, Chiu T, Foley KP, Osorio-Fuentealba C, Antonescu CN, Bayer KU, Bilan PJ, Klip A. Myo1c binding to submembrane actin mediates insulin-induced tethering of GLUT4 vesicles. Mol Biol Cell 2012; 23:4065-78. [PMID: 22918957 PMCID: PMC3469521 DOI: 10.1091/mbc.e12-04-0263] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
GLUT4-containing vesicles cycle between the plasma membrane and intracellular compartments. Insulin promotes GLUT4 exocytosis by regulating GLUT4 vesicle arrival at the cell periphery and its subsequent tethering, docking, and fusion with the plasma membrane. The molecular machinery involved in GLUT4 vesicle tethering is unknown. We show here that Myo1c, an actin-based motor protein that associates with membranes and actin filaments, is required for insulin-induced vesicle tethering in muscle cells. Myo1c was found to associate with both mobile and tethered GLUT4 vesicles and to be required for vesicle capture in the total internal reflection fluorescence (TIRF) zone beneath the plasma membrane. Myo1c knockdown or overexpression of an actin binding-deficient Myo1c mutant abolished insulin-induced vesicle immobilization, increased GLUT4 vesicle velocity in the TIRF zone, and prevented their externalization. Conversely, Myo1c overexpression immobilized GLUT4 vesicles in the TIRF zone and promoted insulin-induced GLUT4 exposure to the extracellular milieu. Myo1c also contributed to insulin-dependent actin filament remodeling. Thus we propose that interaction of vesicular Myo1c with cortical actin filaments is required for insulin-mediated tethering of GLUT4 vesicles and for efficient GLUT4 surface delivery in muscle cells.
Collapse
Affiliation(s)
- Shlomit Boguslavsky
- Cell Biology Program, Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Montessuit C, Lerch R. Regulation and dysregulation of glucose transport in cardiomyocytes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1833:848-56. [PMID: 22967513 DOI: 10.1016/j.bbamcr.2012.08.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 08/08/2012] [Accepted: 08/10/2012] [Indexed: 11/29/2022]
Abstract
The ability of the heart muscle to derive energy from a wide variety of substrates provides the myocardium with remarkable capacity to adapt to the ever-changing metabolic environment depending on factors including nutritional state and physical activity. There is increasing evidence that loss of metabolic flexibility of the myocardium contributes to cardiac dysfunction in disease conditions such as diabetes, ischemic heart disease and heart failure. At the level of glucose metabolism reduced metabolic adaptation in most cases is characterized by impaired stimulation of transarcolemmal glucose transport in the cardiomyocytes in response to insulin, referred to as insulin resistance, or to other stimuli such as energy deficiency. This review discusses cellular mechanisms involved in the regulation of glucose uptake in cardiomyocytes and their potential implication in impairment of stimulation of glucose transport under disease conditions. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction.
Collapse
Affiliation(s)
- Christophe Montessuit
- Department of Medical Specialties, Geneva University Hospitals, Geneva, Switzerland.
| | | |
Collapse
|
41
|
Kim MS, Hur HJ, Kwon DY, Hwang JT. Tangeretin stimulates glucose uptake via regulation of AMPK signaling pathways in C2C12 myotubes and improves glucose tolerance in high-fat diet-induced obese mice. Mol Cell Endocrinol 2012; 358:127-34. [PMID: 22476082 DOI: 10.1016/j.mce.2012.03.013] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 03/17/2012] [Accepted: 03/20/2012] [Indexed: 11/23/2022]
Abstract
Although the flavonoid tangeretin (5, 6, 7, 8, 4'-pentamethoxyflavone) is known to possess beneficial health effects, the anti-diabetic effects and the mechanism of action have not been elucidated. Treatment with 100 μM tangeretin significantly increased the uptake of 2-NBDG in C2C12 myotubes. We also found that AMPK and AS160 were markedly phosphorylated by tangeretin treatment. In addition, pretreatment with an AMPK inhibitor significantly abrogated tangeretin-stimulated AS160 phosphorylation, glucose uptake, and Glut4 translocation from the cytosol to the plasma membrane. Furthermore, disruption of AMPK using siRNA transfection prevented the glucose uptake stimulated by tangeretin. We also examined the anti-diabetic properties of tangeretin in mice on HFD. Administration of HFD plus 200 mg/kg of tangeretin significantly altered weight gain, glucose tolerance, total cholesterol levels, and the secretion of adipocytokines, such as adiponectin, leptin, resistin, IL-6, and MCP-1. Moreover, AMPK was activated by 200 mg/kg of tangeretin in mouse muscle tissue, as expected from the cell system. These results suggest that tangeretin exerts anti-diabetic effects in both cell culture and mouse models, and these effects are necessary for activating AMPK.
Collapse
|
42
|
Butruille L, Mayeur S, Duparc T, Knauf C, Moitrot E, Fajardy I, Valet P, Storme L, Deruelle P, Lesage J. Prenatal fasudil exposure alleviates fetal growth but programs hyperphagia and overweight in the adult male rat. Eur J Pharmacol 2012; 689:278-84. [PMID: 22683867 DOI: 10.1016/j.ejphar.2012.05.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 05/21/2012] [Accepted: 05/24/2012] [Indexed: 11/26/2022]
Abstract
Numerous data indicate that Rho kinase inhibitors, such as Fasudil, may constitute a novel therapy for cardiovascular and metabolic diseases. We evaluated long-term effects of exposure to Fasudil during late gestation (10 mg/day) in male rat offspring from birth until 9 months. We also analyzed its effects in offspring from hypertensive mothers treated with a nitric oxide synthesis inhibitor (L-NAME; 50 mg/day). Prenatal exposure to Fasudil did not affect birth weight, but increased body weight from postnatal day 7 (P7) to 9 months. In intrauterine growth-restricted (IUGR) fetuses exposed to L-NAME, maternal Fasudil treatment increased birth weight. At P42 and P180, rats exposed to Fasudil and L-NAME showed alterations of their food intake as well as an increased basal glycemia associated with mild glucose intolerance at 6 months which was also observed in Fasudil-exposed rats. In 9 month-old rats, exposure to Fasudil increased the daily food intake as well as hypothalamic mRNA level of the orexigenic NPY peptide without modulation of the anorexigenic POMC gene expression. Altogether, our data suggest that prenatal Fasudil exposure alleviates fetal growth in IUGR rats, but programs long-term metabolic disturbances including transient perturbations of glucose metabolism, a persistent increase of body weight gain, hyperphagia and an augmented expression of hypothalamic NPY orexigenic gene. We postulate that Fasudil treatment during perinatal periods may predispose individuals to the development of metabolic disorders.
Collapse
Affiliation(s)
- Laura Butruille
- Univ Lille Nord de France, Unité Environnement Périnatal et Croissance, EA 4489, Faculté de Médecine, Pôle Recherche, Bâtiment SN4, Villeneuve d'Ascq, IFR 114, 59045 Lille, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Baas D, Caussanel-Boude S, Guiraud A, Calhabeu F, Delaune E, Pilot F, Chopin E, Machuca-Gayet I, Vernay A, Bertrand S, Rual JF, Jurdic P, Hill DE, Vidal M, Schaeffer L, Goillot E. CKIP-1 regulates mammalian and zebrafish myoblast fusion. J Cell Sci 2012; 125:3790-800. [PMID: 22553210 DOI: 10.1242/jcs.101048] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Multinucleated muscle fibres arise by fusion of precursor cells called myoblasts. We previously showed that CKIP-1 ectopic expression in C2C12 myoblasts increased cell fusion. In this work, we report that CKIP-1 depletion drastically impairs C2C12 myoblast fusion in vitro and in vivo during zebrafish muscle development. Within developing fast-twich myotome, Ckip-1 localises at the periphery of fast precursor cells, closed to the plasma membrane. Unlike wild-type myoblasts that form spatially arrayed multinucleated fast myofibres, Ckip-1-deficient myoblasts show a drastic reduction in fusion capacity. A search for CKIP-1 binding partners identified the ARPC1 subunit of Arp2/3 actin nucleation complex essential for myoblast fusion. We demonstrate that CKIP-1, through binding to plasma membrane phosphoinositides via its PH domain, regulates cell morphology and lamellipodia formation by recruiting the Arp2/3 complex at the plasma membrane. These results establish CKIP-1 as a regulator of cortical actin that recruits the Arp2/3 complex at the plasma membrane essential for muscle precursor elongation and fusion.
Collapse
Affiliation(s)
- Dominique Baas
- Equipe Différenciation Neuromusculaire, Laboratoire de Biologie Moléculaire de la Cellule, CNRS UMR 5239/ENS Lyon, Université de Lyon, IFR128 Biosciences Lyon-Gerland, 46 Allée d'Italie, 69364 LYON cedex 07, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Rondas D, Tomas A, Soto-Ribeiro M, Wehrle-Haller B, Halban PA. Novel mechanistic link between focal adhesion remodeling and glucose-stimulated insulin secretion. J Biol Chem 2011; 287:2423-36. [PMID: 22139838 DOI: 10.1074/jbc.m111.279885] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Actin cytoskeleton remodeling is well known to be positively involved in glucose-stimulated pancreatic β cell insulin secretion. We have observed glucose-stimulated focal adhesion remodeling at the β cell surface and have shown this to be crucial for glucose-stimulated insulin secretion. However, the mechanistic link between such remodeling and the insulin secretory machinery remained unknown and was the major aim of this study. MIN6B1 cells, a previously validated model of primary β cell function, were used for all experiments. Total internal reflection fluorescence microscopy revealed the glucose-responsive co-localization of focal adhesion kinase (FAK) and paxillin with integrin β1 at the basal cell surface after short term stimulation. In addition, blockade of the interaction between β1 integrins and the extracellular matrix with an anti-β1 integrin antibody (Ha2/5) inhibited short term glucose-induced phosphorylation of FAK (Tyr-397), paxillin (Tyr-118), and ERK1/2 (Thr-202/Tyr-204). Pharmacological inhibition of FAK activity blocked glucose-induced actin cytoskeleton remodeling and glucose-induced disruption of the F-actin/SNAP-25 association at the plasma membrane as well as the distribution of insulin granules to regions in close proximity to the plasma membrane. Furthermore, FAK inhibition also completely blocked short term glucose-induced activation of the Akt/AS160 signaling pathway. In conclusion, these results indicate 1) that glucose-induced activation of FAK, paxillin, and ERK1/2 is mediated by β1 integrin intracellular signaling, 2) a mechanism whereby FAK mediates glucose-induced actin cytoskeleton remodeling, hence allowing docking and fusion of insulin granules to the plasma membrane, and 3) a possible functional role for the Akt/AS160 signaling pathway in the FAK-mediated regulation of glucose-stimulated insulin secretion.
Collapse
Affiliation(s)
- Dieter Rondas
- Department of Genetic Medicine and Development, University of Geneva, CH-1211 Geneva 4, Switzerland.
| | | | | | | | | |
Collapse
|
45
|
Chiu TT, Jensen TE, Sylow L, Richter EA, Klip A. Rac1 signalling towards GLUT4/glucose uptake in skeletal muscle. Cell Signal 2011; 23:1546-54. [DOI: 10.1016/j.cellsig.2011.05.022] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Accepted: 05/31/2011] [Indexed: 12/27/2022]
|
46
|
Maarbjerg SJ, Sylow L, Richter EA. Current understanding of increased insulin sensitivity after exercise - emerging candidates. Acta Physiol (Oxf) 2011; 202:323-35. [PMID: 21352505 DOI: 10.1111/j.1748-1716.2011.02267.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Exercise counteracts insulin resistance and improves glucose homeostasis in many ways. Apart from increasing muscle glucose uptake quickly, exercise also clearly increases muscle insulin sensitivity in the post-exercise period. This review will focus on the mechanisms responsible for this increased insulin sensitivity. It is believed that increased sarcolemmal content of the glucose transporter GLUT4 can explain the phenomenon to some extent. Surprisingly no improvement in the proximal insulin signalling pathway is observed at the level of the insulin receptor, IRS1, PI3K or Akt. Recently more distal signalling component in the insulin signalling pathway such as aPKC, Rac1, TBC1D4 and TBC1D1 have been described. These are all affected by both insulin and exercise which means that they are likely converging points in promoting GLUT4 translocation and therefore possible candidates for regulating insulin sensitivity after exercise. Whereas TBC1D1 does not appear to regulate insulin sensitivity after exercise, correlative evidence in contrast suggests TBC1D4 to be a relevant candidate. Little is known about aPKC and Rac1 in relation to insulin sensitivity after exercise. Besides mechanisms involved in signalling to GLUT4 translocation, factors influencing the trans-sarcolemmal glucose concentration gradient might also be important. With regard to the interstitial glucose concentration microvascular perfusion is particular relevant as correlative evidence supports a connection between insulin sensitivity and microvascular perfusion. Thus, there are new candidates at several levels which collectively might explain the phenomenon.
Collapse
Affiliation(s)
- S J Maarbjerg
- Molecular Physiology Group, Department of Exercise and Sport Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | | |
Collapse
|
47
|
Foley K, Boguslavsky S, Klip A. Endocytosis, recycling, and regulated exocytosis of glucose transporter 4. Biochemistry 2011; 50:3048-61. [PMID: 21405107 DOI: 10.1021/bi2000356] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Glucose transporter 4 (GLUT4) is responsible for the uptake of glucose into muscle and adipose tissues. Under resting conditions, GLUT4 is dynamically retained through idle cycling among selective intracellular compartments, from whence it undergoes slow recycling to the plasma membrane (PM). This dynamic retention can be released by command from intracellular signals elicited by insulin and other stimuli, which result in 2-10-fold increases in the surface level of GLUT4. Insulin-derived signals promote translocation of GLUT4 to the PM from a specialized compartment termed GLUT4 storage vesicles (GSV). Much effort has been devoted to the characterization of the intracellular compartments and dynamics of GLUT4 cycling and to the signals by which GLUT4 is sorted into, and recruited from, GSV. This review summarizes our understanding of intracellular GLUT4 traffic during its internalization from the membrane, its slow, constitutive recycling, and its regulated exocytosis in response to insulin. In spite of specific differences in GLUT4 dynamic behavior in adipose and muscle cells, the generalities of its endocytic and exocytic itineraries are consistent and an array of regulatory proteins that regulate each vesicular traffic event emerges from these cell systems.
Collapse
Affiliation(s)
- Kevin Foley
- Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario M4G 1X8, Canada
| | | | | |
Collapse
|
48
|
Lee JO, Lee SK, Jung JH, Kim JH, You GY, Kim SJ, Park SH, Uhm KO, Kim HS. Metformin induces Rab4 through AMPK and modulates GLUT4 translocation in skeletal muscle cells. J Cell Physiol 2011; 226:974-81. [PMID: 20857458 DOI: 10.1002/jcp.22410] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Metformin is a major oral anti-diabetic drug and is known as an insulin sensitizer. However, the mechanism by which metformin acts is unclear. In this study, we found that AICAR, an AMPK activator, and metformin increased the expression of Rab4 mRNA and protein levels in skeletal muscle C2C12 cells. The promoter activity of Rab4 was increased by metformin in an AMPK-dependent manner. Metformin stimulated the phosphorylation of AS160, Akt substrate, and Rab GTPase activating protein (GAP), and also increased the phosphorylation of PKC-zeta, which is a critical molecule for glucose uptake. Knockdown of AMPK blocked the metformin-induced phosphorylation of AS160/PKC-zeta. In addition, a colorimetric absorbance assay showed that insulin-induced translocation of GLUT4 was suppressed in Rab4 knockdown cells. Moreover, Rab4 interacted with PKC-zeta but not with GLUT4. The C-terminal-deleted Rab4 mutant, Rab4ΔCT, showed diffuse sub-cellular localization, while wild-type Rab4 localized exclusively to the perinuclear membrane. Unlike Rab4ΔCT, wild-type Rab4 co-localized with PKC-zeta. Together, these results demonstrate that metformin induces Rab4 expression via AMPK-AS160-PKC-zeta and modulates insulin-mediated GLUT4 translocation.
Collapse
Affiliation(s)
- Jung Ok Lee
- Department of Anatomy, Korea University College of Medicine, Seoul, Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Hoffman NJ, Elmendorf JS. Signaling, cytoskeletal and membrane mechanisms regulating GLUT4 exocytosis. Trends Endocrinol Metab 2011; 22:110-6. [PMID: 21216617 PMCID: PMC3049829 DOI: 10.1016/j.tem.2010.12.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 12/03/2010] [Accepted: 12/06/2010] [Indexed: 10/25/2022]
Abstract
Solving how insulin regulates glucose transport into skeletal muscle and adipose tissue remains a fundamental challenge in biology and a significant issue in medicine. A central feature of this process is the coordinated accumulation of the glucose transporter GLUT4 into the plasma membrane. New signaling and cytoskeletal mechanisms of insulin-stimulated GLUT4 exocytosis are of emerging interest, particularly those at or just beneath the plasma membrane. This review examines signals that functionally engage GLUT4 exocytosis, considers cytoskeletal regulation of the stimulated GLUT4 itinerary, and appraises the involvement of plasma membrane parameters in GLUT4 control. We also explore how these newly-defined signaling, cytoskeletal and membrane mechanisms could be of therapeutic interest in the treatment and/or prevention of GLUT4 dysregulation in disease.
Collapse
Affiliation(s)
- Nolan J Hoffman
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Centers for Diabetes Research, Membrane Biosciences, and Vascular Biology and Medicine, VanNuys Medical Science Building Room 308A, Indianapolis, IN 46202, USA
| | | |
Collapse
|
50
|
Mitra S, Cheng KW, Mills GB. Rab GTPases implicated in inherited and acquired disorders. Semin Cell Dev Biol 2010; 22:57-68. [PMID: 21147240 DOI: 10.1016/j.semcdb.2010.12.005] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 12/06/2010] [Accepted: 12/06/2010] [Indexed: 01/05/2023]
Abstract
The endocytotic machinery imports, transports and exports receptors and associated molecules between the plasma membrane and various cytoplasmic chambers resulting in selective recycling, degradation, or secretion of molecules and signaling complexes. Trafficking of receptors, growth factors, nutrients, cytokines, integrins as well as pathogens dictates the kinetics and magnitude of signal transduction cascades. Understandably, alterations in the 'fate' of such cargo complexes have profound physiologic and pathophysiologic implications. Rab GTPases regulate endocytosis by decorating intracellular vesicles and targeting these vesicles along with their cargoes to appropriate subcellular compartments. In the last decade, the number of genetic diseases driven by germline mutations in Rab GTPases or their interacting proteins, has increased and there is growing evidence of aberrant Rab GTPase function in acquired pathophysiologies such as immune deficiency, infection, obesity, diabetes and cancer.
Collapse
Affiliation(s)
- Shreya Mitra
- Department of Systems Biology, The University of Texas, MD Anderson Cancer Center, Houston, TX 77054-1942, USA.
| | | | | |
Collapse
|