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Säll J, Lindahl M, Fritzen AM, Fryklund C, Kopietz F, Nyberg E, Warvsten A, Morén B, Foretz M, Kiens B, Stenkula KG, Göransson O. Salt-inducible kinases are required for glucose uptake and insulin signaling in human adipocytes. Obesity (Silver Spring) 2023; 31:2515-2529. [PMID: 37608474 DOI: 10.1002/oby.23858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 05/25/2023] [Accepted: 05/29/2023] [Indexed: 08/24/2023]
Abstract
OBJECTIVE Salt-inducible kinase 2 (SIK2) is abundantly expressed in adipocytes and downregulated in adipose tissue from individuals with obesity or insulin resistance. The main aims of this work were to investigate the involvement of SIKs in the regulation of glucose uptake in primary mature human adipocytes and to identify mechanisms underlying this regulation. METHODS Primary mature adipocytes were isolated from human, rat, or mouse adipose tissue and treated with pan-SIK inhibitors. Adipocytes isolated from wild type, ob/ob, and SIK2 knockout mice were also used. Glucose uptake was examined by glucose tracer assay. The insulin signaling pathway was monitored by Western blotting, co-immunoprecipitation, and total internal reflection fluorescence microscopy. RESULTS This study demonstrates that SIK2 is downregulated in obese ob/ob mice and that SIK activity is required for intact glucose uptake in primary human and mouse adipocytes. The underlying mechanism involves direct effects on the insulin signaling pathway, likely at the level of phosphatidylinositol (3,4,5)-trisphosphate (PIP3) generation or breakdown. Moreover, lack of SIK2 alone is sufficient to attenuate glucose uptake in mouse adipocytes. CONCLUSIONS SIK2 is required for insulin action in human adipocytes, and the mechanism includes direct effects on the insulin signaling pathway.
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Affiliation(s)
- Johanna Säll
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Maria Lindahl
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Andreas M Fritzen
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Claes Fryklund
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Franziska Kopietz
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Emma Nyberg
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Anna Warvsten
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Björn Morén
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Marc Foretz
- Institut Cochin, INSERM, CNRS, Department of Endocrinology, Metabolism and Diabetes, Université Paris Cité, Paris, France
| | - Bente Kiens
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Karin G Stenkula
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Olga Göransson
- Department of Experimental Medical Science, Lund University, Lund, Sweden
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2
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Shi F, de Fatima Silva F, Liu D, Patel HU, Xu J, Zhang W, Türk C, Krüger M, Collins S. Salt-inducible kinase inhibition promotes the adipocyte thermogenic program and adipose tissue browning. Mol Metab 2023; 74:101753. [PMID: 37321371 PMCID: PMC10319839 DOI: 10.1016/j.molmet.2023.101753] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 05/30/2023] [Accepted: 06/08/2023] [Indexed: 06/17/2023] Open
Abstract
OBJECTIVE Norepinephrine stimulates the adipose tissue thermogenic program through a β-adrenergic receptor (βAR)-cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling cascade. We discovered that a noncanonical activation of the mechanistic target of rapamycin complex 1 (mTORC1) by PKA is required for the βAR-stimulation of adipose tissue browning. However, the downstream events triggered by PKA-phosphorylated mTORC1 activation that drive this thermogenic response are not well understood. METHODS We used a proteomic approach of Stable Isotope Labeling by/with Amino acids in Cell culture (SILAC) to characterize the global protein phosphorylation profile in brown adipocytes treated with the βAR agonist. We identified salt-inducible kinase 3 (SIK3) as a candidate mTORC1 substrate and further tested the effect of SIK3 deficiency or SIK inhibition on the thermogenic gene expression program in brown adipocytes and in mouse adipose tissue. RESULTS SIK3 interacts with RAPTOR, the defining component of the mTORC1 complex, and is phosphorylated at Ser884 in a rapamycin-sensitive manner. Pharmacological SIK inhibition by a pan-SIK inhibitor (HG-9-91-01) in brown adipocytes increases basal Ucp1 gene expression and restores its expression upon blockade of either mTORC1 or PKA. Short-hairpin RNA (shRNA) knockdown of Sik3 augments, while overexpression of SIK3 suppresses, Ucp1 gene expression in brown adipocytes. The regulatory PKA phosphorylation domain of SIK3 is essential for its inhibition. CRISPR-mediated Sik3 deletion in brown adipocytes increases type IIa histone deacetylase (HDAC) activity and enhances the expression of genes involved in thermogenesis such as Ucp1, Pgc1α, and mitochondrial OXPHOS complex protein. We further show that HDAC4 interacts with PGC1α after βAR stimulation and reduces lysine acetylation in PGC1α. Finally, a SIK inhibitor well-tolerated in vivo (YKL-05-099) can stimulate the expression of thermogenesis-related genes and browning of mouse subcutaneous adipose tissue. CONCLUSIONS Taken together, our data reveal that SIK3, with the possible contribution of other SIKs, functions as a phosphorylation switch for β-adrenergic activation to drive the adipose tissue thermogenic program and indicates that more work to understand the role of the SIKs is warranted. Our findings also suggest that maneuvers targeting SIKs could be beneficial for obesity and related cardiometabolic disease.
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Affiliation(s)
- Fubiao Shi
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Flaviane de Fatima Silva
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo 05508-000, Brazil
| | - Dianxin Liu
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Hari U Patel
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jonathan Xu
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Wei Zhang
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Clara Türk
- CECAD Research Center, Institute for Genetics, University of Cologne, Cologne 50931, Germany
| | - Marcus Krüger
- CECAD Research Center, Institute for Genetics, University of Cologne, Cologne 50931, Germany; Center for Molecular Medicine (CMMC), University of Cologne, Cologne 50931, Germany
| | - Sheila Collins
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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Vaváková M, Hofwimmer K, Laurencikiene J, Göransson O. Mechanism of TNFα-induced downregulation of salt-inducible kinase 2 in adipocytes. Sci Rep 2023; 13:10559. [PMID: 37386070 PMCID: PMC10310826 DOI: 10.1038/s41598-023-37340-5] [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: 02/17/2023] [Accepted: 06/20/2023] [Indexed: 07/01/2023] Open
Abstract
Salt-inducible kinase 2 (SIK2) is highly expressed in white adipocytes, but downregulated in individuals with obesity and insulin resistance. These conditions are often associated with a low-grade inflammation in adipose tissue. We and others have previously shown that SIK2 is downregulated by tumor necrosis factor α (TNFα), however, involvement of other pro-inflammatory cytokines, or the mechanisms underlying TNFα-induced SIK2 downregulation, remain to be elucidated. In this study we have shown that TNFα downregulates SIK2 protein expression not only in 3T3L1- but also in human in vitro differentiated adipocytes. Furthermore, monocyte chemoattractant protein-1 and interleukin (IL)-1β, but not IL-6, might also contribute to SIK2 downregulation during inflammation. We observed that TNFα-induced SIK2 downregulation occurred also in the presence of pharmacological inhibitors against several kinases involved in inflammation, namely c-Jun N-terminal kinase, mitogen activated protein kinase kinase 1, p38 mitogen activated protein kinase or inhibitor of nuclear factor kappa-B kinase (IKK). However, IKK may be involved in SIK2 regulation as we detected an increase of SIK2 when inhibiting IKK in the absence of TNFα. Increased knowledge about inflammation-induced downregulation of SIK2 could ultimately be used to develop strategies for the reinstalment of SIK2 expression in insulin resistance.
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Affiliation(s)
- Magdaléna Vaváková
- Protein Phosphorylation Research Group, Section for Diabetes, Metabolism and Endocrinology, Department of Experimental Medical Science, Lund University, Biomedical Centre C11, Klinikgatan 28, 221 84, Lund, Sweden
| | - Kaisa Hofwimmer
- Lipid Laboratory, Unit of Endocrinology, Department of Medicine Huddinge, Karolinska Institute, Stockholm, Sweden
| | - Jurga Laurencikiene
- Lipid Laboratory, Unit of Endocrinology, Department of Medicine Huddinge, Karolinska Institute, Stockholm, Sweden
| | - Olga Göransson
- Protein Phosphorylation Research Group, Section for Diabetes, Metabolism and Endocrinology, Department of Experimental Medical Science, Lund University, Biomedical Centre C11, Klinikgatan 28, 221 84, Lund, Sweden.
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Liu B, Zhang L, Yang H, Chen X, Zheng H, Liao X. SIK2 protects against renal tubular injury and the progression of diabetic kidney disease. Transl Res 2023; 253:16-30. [PMID: 36075517 DOI: 10.1016/j.trsl.2022.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/17/2022] [Accepted: 08/22/2022] [Indexed: 02/03/2023]
Abstract
Despite optimal medical therapy, many patients with diabetic kidney disease (DKD) progress to end-stage renal disease. The identification of new biomarkers and drug targets for DKD is required for the development of more effective therapies. The apoptosis of renal tubular epithelial cells is a key feature of the pathogenicity associated with DKD. SIK2, a salt-inducible kinase, regulates important biological processes, such as energy metabolism, cell cycle progression and cellular apoptosis. In our current study, a notable decrease in the expression of SIK2 was detected in the renal tubules of DKD patients and murine models. Functional experiments demonstrated that deficiency or inactivity of SIK2 aggravates tubular injury and interstitial fibrosis in diabetic mice. Based on transcriptome sequencing, molecular mechanism exploration revealed that SIK2 overexpression reduces endoplasmic reticulum (ER) stress-mediated tubular epithelial apoptosis by inhibiting the histone acetyltransferase activity of p300 to activate HSF1/Hsp70. Furthermore, the specific restoration of SIK2 in tubules blunts tubular and interstitial impairments in diabetic and vancomycin-induced kidney disease mice. Together, these findings indicate that SIK2 protects against renal tubular injury and the progression of kidney disease, and make a compelling case for targeting SIK2 for therapy in DKD.
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Affiliation(s)
- Bingyao Liu
- Department of Endocrinology, Chongqing Education Commission Key Laboratory of Diabetic Translational Research, the Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Linlin Zhang
- Department of Endocrinology, Chongqing Education Commission Key Laboratory of Diabetic Translational Research, the Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Hang Yang
- Department of Endocrinology, Chongqing Education Commission Key Laboratory of Diabetic Translational Research, the Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Xinyu Chen
- Department of Pathology, Chongqing University Cancer Hospital, Chongqing, China
| | - Hongting Zheng
- Department of Endocrinology, Chongqing Education Commission Key Laboratory of Diabetic Translational Research, the Second Affiliated Hospital of Army Medical University, Chongqing, China.
| | - Xiaoyu Liao
- Department of Endocrinology, Chongqing Education Commission Key Laboratory of Diabetic Translational Research, the Second Affiliated Hospital of Army Medical University, Chongqing, China.
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Shi M, Zhou Y, Wei H, Zhang X, Du M, Zhou Y, Yin Y, Li X, Tang X, Sun L, Xu D, Li X. Interactions between curcumin and human salt-induced kinase 3 elucidated from computational tools and experimental methods. Front Pharmacol 2023; 14:1116098. [PMID: 37124223 PMCID: PMC10133576 DOI: 10.3389/fphar.2023.1116098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 04/03/2023] [Indexed: 05/02/2023] Open
Abstract
Natural products are widely used for treating mitochondrial dysfunction-related diseases and cancers. Curcumin, a well-known natural product, can be potentially used to treat cancer. Human salt-induced kinase 3 (SIK3) is one of the target proteins for curcumin. However, the interactions between curcumin and human SIK3 have not yet been investigated in detail. In this study, we studied the binding models for the interactions between curcumin and human SIK3 using computational tools such as homology modeling, molecular docking, molecular dynamics simulations, and binding free energy calculations. The open activity loop conformation of SIK3 with the ketoenol form of curcumin was the optimal binding model. The I72, V80, A93, Y144, A145, and L195 residues played a key role for curcumin binding with human SIK3. The interactions between curcumin and human SIK3 were also investigated using the kinase assay. Moreover, curcumin exhibited an IC50 (half-maximal inhibitory concentration) value of 131 nM, and it showed significant antiproliferative activities of 9.62 ± 0.33 µM and 72.37 ± 0.37 µM against the MCF-7 and MDA-MB-23 cell lines, respectively. This study provides detailed information on the binding of curcumin with human SIK3 and may facilitate the design of novel salt-inducible kinases inhibitors.
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Affiliation(s)
- Mingsong Shi
- NHC Key Laboratory of Nuclear Technology Medical Transformation, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, Sichuan, China
| | - Yan Zhou
- NHC Key Laboratory of Nuclear Technology Medical Transformation, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, Sichuan, China
| | - Haoche Wei
- State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xinyu Zhang
- West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China
| | - Meng Du
- College of Chemistry, MOE Key Laboratory of Green Chemistry and Technology, Sichuan University, Chengdu, Sichuan, China
| | - Yanting Zhou
- Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnocentric of Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China
| | - Yuan Yin
- NHC Key Laboratory of Nuclear Technology Medical Transformation, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, Sichuan, China
| | - Xinghui Li
- West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China
| | - Xinyi Tang
- West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China
| | - Liang Sun
- Shenzhen Shuli Tech Co., Ltd, Shenzhen, Guangdong, China
| | - Dingguo Xu
- College of Chemistry, MOE Key Laboratory of Green Chemistry and Technology, Sichuan University, Chengdu, Sichuan, China
- Research Center for Material Genome Engineering, Sichuan University, Chengdu, Sichuan, China
- *Correspondence: Dingguo Xu, ; Xiaoan Li,
| | - Xiaoan Li
- NHC Key Laboratory of Nuclear Technology Medical Transformation, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, Sichuan, China
- *Correspondence: Dingguo Xu, ; Xiaoan Li,
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Stern S, Kurian R, Wang H. Clinical Relevance of the Constitutive Androstane Receptor. Drug Metab Dispos 2022; 50:1010-1018. [PMID: 35236665 PMCID: PMC11022901 DOI: 10.1124/dmd.121.000483] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 02/10/2022] [Indexed: 11/22/2022] Open
Abstract
Constitutive androstane receptor (CAR) (NR1I3), a xenobiotic receptor, has long been considered a master mediator of drug disposition and detoxification. Accumulating evidence indicates that CAR also participates in various physiologic and pathophysiological pathways regulating the homeostasis of glucose, lipid, and bile acids, and contributing to cell proliferation, tissue regeneration and repair, as well as cancer development. The expression and activity of CAR can be regulated by various factors, including small molecular modulators, CAR interaction with other transcription factors, and naturally occurring genetic variants. Given that the influence of CAR has extended beyond the realm of drug metabolism and disposition and has expanded into a potential modulator of human diseases, growing efforts have centered on understanding its clinical relevance and impact on human pathophysiology. This review highlights the current information available regarding the contribution of CAR to various metabolic disorders and cancers and ponders the possible challenges that might arise from pursuing CAR as a potential therapeutic target for these diseases. SIGNIFICANCE STATEMENT: The growing importance of the constitutive androstane receptor (CAR) in glucose and lipid metabolism as well as its potential implication in cell proliferation emphasizes a need to keenly understand the biological function and clinical impact of CAR. This minireview captures the clinical relevance of CAR by highlighting its role in metabolic disorders and cancer development.
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Affiliation(s)
- Sydney Stern
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland
| | - Ritika Kurian
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland
| | - Hongbing Wang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland
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7
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Bourouh M, Marignani PA. The Tumor Suppressor Kinase LKB1: Metabolic Nexus. Front Cell Dev Biol 2022; 10:881297. [PMID: 35573694 PMCID: PMC9097215 DOI: 10.3389/fcell.2022.881297] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 04/07/2022] [Indexed: 11/13/2022] Open
Abstract
Liver kinase B1 (LKB1) is a multitasking tumor suppressor kinase that is implicated in multiple malignancies such as lung, gastrointestinal, pancreatic, and breast. LKB1 was first identified as the gene responsible for Peutz-Jeghers syndrome (PJS) characterized by hamartomatous polyps and oral mucotaneous pigmentation. LKB1 functions to activate AMP-activated protein kinase (AMPK) during energy stress to shift metabolic processes from active anabolic pathways to active catabolic pathways to generate ATP. Genetic loss or inactivation of LKB1 promotes metabolic reprogramming and metabolic adaptations of cancer cells that fuel increased growth and division rates. As a result, LKB1 loss is associated with increased aggressiveness and treatment options for patients with LKB1 mutant tumors are limited. Recently, there has been new insights into the role LKB1 has on metabolic regulation and the identification of potential vulnerabilities in LKB1 mutant tumors. In this review, we discuss the tumor suppressive role of LKB1 and the impact LKB1 loss has on metabolic reprograming in cancer cells, with a focus on lung cancer. We also discuss potential therapeutic avenues to treat malignancies associated with LKB1 loss by targeting aberrant metabolic pathways associated with LKB1 loss.
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Affiliation(s)
- Mohammed Bourouh
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Dalhousie University Halifax, Halifax, NS, Canada
| | - Paola A Marignani
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Dalhousie University Halifax, Halifax, NS, Canada
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Zhang R, Liu Y, Zhong W, Hu Z, Wu C, Ma M, Zhang Y, He X, Wang L, Li S, Hong Y. SIK2 Improving Mitochondrial Autophagy Restriction Induced by Cerebral Ischemia-Reperfusion in Rats. Front Pharmacol 2022; 13:683898. [PMID: 35586047 PMCID: PMC9108450 DOI: 10.3389/fphar.2022.683898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 03/30/2022] [Indexed: 11/13/2022] Open
Abstract
Previous studies have shown that Salt-induced kinase-2(SIK2) is involved in the regulation of various energy-metabolism-related reactions, and it also can regulate angiogenesis after cerebral ischemia-reperfusion. However, it is unclear whether SIK2 can regulate energy metabolism in cerebral ischemia-reperfusion injury. As mitochondria plays an important role in energy metabolism, whether SIK2 regulates energy metabolism through affecting mitochondrial changes is also worth to be explored. In this study, rats were treated with adeno-associated virus-SIK2-Green fluorescent protein (AAV-SIK2-GFP) for the overexpression of SIK2 before middle cerebral artery occlusion (MCAO). We found that SIK2 overexpression could alleviate the neuronal damage, reduce the area of cerebral infarction, and increase the adenosine triphosphate (ATP) content, which could promote the expression of phosphorylated-mammalian target of rapamycin-1 (p-mTORC1), hypoxia-inducible factor-1α (HIF-1α), phosphatase and tensin homologue-induced putative kinase 1 (PINK1) and E3 ubiquitinligating enzyme (Parkin). Transmission electron microscopy revealed that SIK2 overexpression enhanced mitochondrial autophagy. It is concluded that SIK2 can ameliorate neuronal injury and promote the energy metabolism by regulating the mTOR pathway during cerebral ischemia-reperfusion, and this process is related to mitochondrial autophagy.
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Affiliation(s)
- Ran Zhang
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
- Department of Clinical, Wannan Medical College, Wuhu, China
| | - Yun Liu
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
| | - Wenhua Zhong
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
| | - Zebo Hu
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
| | - Chao Wu
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
| | - Mengyao Ma
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
| | - Yi Zhang
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
| | - Xiangyun He
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
| | - Lin Wang
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
- *Correspondence: Lin Wang, ; Shu Li, ; Yun Hong,
| | - Shu Li
- Department of Pathophysiology, Wannan Medical College, Wuhu, China
- Department of Public Health, Wannan Medical College, Wuhu, China
- *Correspondence: Lin Wang, ; Shu Li, ; Yun Hong,
| | - Yun Hong
- Department of Ultrasonic Medicine, Yijishan Hospital, Wannan Medical College, Wuhu, China
- *Correspondence: Lin Wang, ; Shu Li, ; Yun Hong,
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Cabrera D, Rao I, Raasch F, Solis N, Pizarro M, Freire M, Sáenz De Urturi D, Ramírez CA, Triantafilo N, León J, Riquelme A, Barrera F, Baudrand R, Aspichueta P, Arrese M, Arab JP. Mineralocorticoid receptor modulation by dietary sodium influences NAFLD development in mice. Ann Hepatol 2022; 24:100357. [PMID: 33940220 DOI: 10.1016/j.aohep.2021.100357] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/02/2021] [Accepted: 03/02/2021] [Indexed: 02/04/2023]
Abstract
INTRODUCTION AND OBJECTIVES Nonalcoholic-fatty-liver disease (NAFLD) is considered the hepatic manifestation of metabolic syndrome (MetS). Mineralocorticoid receptor (MR) activation is associated with increased risk of MetS but few studies have assessed the role of liver MR on NAFLD. We aimed to evaluate the effect of MR modulation by sodium intake in liver injury in experimental models of NAFLD. MATERIALS AND METHODS C57BL/6J mice were fed either a high-fat-diet (HFD) or a choline/methionine deficient (MCD) diet with different sodium concentrations. Hepatic concentration of lipid species, serum aldosterone levels, expression of MR, proinflammatory and profibrotic markers and liver histology were assessed. RESULTS Mice fed with High-Na+/HFD showed a lower MR expression in liver (p = 0.01) and less steatosis on histology (p = 0.04). Consistently, animals from this group exhibited lower levels of serum aldosterone (p = 0.028) and lower hepatic triglyceride content (p = 0.008). This associated to a reduced expression of lipogenic genes, significant changes in lipid subspecies, lower HOMA-IR (p < 0.05), and lower expression of pro-inflammatory and profibrotic markers compared to those mice fed a Low-Na+/HFD. Additionally, mice fed a High-Na+/HFD showed higher expression of salt-inducible kinase (SIK)-1 and lower expression of serum-and-glucocorticoid-inducible kinase (SGK)-1. Similar results were observed with the MCD diet model. CONCLUSION We identified in two experimental models of NAFLD that High-Na+ diet content is associated to lower serum aldosterone levels and hepatic MR downregulation, associated to decreased steatosis and reduced de novo hepatic lipogenesis, proinflammatory and profibrotic markers. Decreased activation of hepatic MR seems to generate beneficial downstream inhibition of lipogenesis in experimental NAFLD.
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Affiliation(s)
- Daniel Cabrera
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile; Facultad de Ciencias Médicas, Universidad Bernardo O Higgins, Santiago, Chile
| | - Isabel Rao
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Fabiola Raasch
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Nancy Solis
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Margarita Pizarro
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Mariela Freire
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | | | | | - Nicolás Triantafilo
- Departamento de Hematologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Jonathan León
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Arnoldo Riquelme
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile; Departamento de Ciencias de la Salud, Facultad de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Francisco Barrera
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Rene Baudrand
- Departamento de Endocrinologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Patricia Aspichueta
- Department of Physiology, University of the Basque Country UPV/EHU, Leioa, Spain; Biocruces Health Research Institute, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Spain
| | - Marco Arrese
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile; Centro de Envejecimiento y Regeneracion (CARE), Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas Pontificia Universidad Catolica de Chile, Santiago, Chile.
| | - Juan P Arab
- Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile; Centro de Envejecimiento y Regeneracion (CARE), Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas Pontificia Universidad Catolica de Chile, Santiago, Chile.
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10
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Yoon YS, Liu W, Van de Velde S, Matsumura S, Wiater E, Huang L, Montminy M. Activation of the adipocyte CREB/CRTC pathway in obesity. Commun Biol 2021; 4:1214. [PMID: 34686752 PMCID: PMC8536733 DOI: 10.1038/s42003-021-02735-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 09/21/2021] [Indexed: 11/09/2022] Open
Abstract
Obesity is a major risk factor for the development of type II diabetes. Increases in adipose tissue mass trigger insulin resistance via the release of pro-inflammatory cytokines from adipocytes and macrophages. CREB and the CRTC coactivators have been found to promote insulin resistance in obesity, although the mechanism is unclear. Here we show that high fat diet feeding activates the CREB/CRTC pathway in adipocytes by decreasing the expression of SIK2, a Ser/Thr kinase that phosphorylates and inhibits CRTCs. SIK2 levels are regulated by the adipogenic factor C/EBPα, whose expression is reduced in obesity. Exposure to PPARγ agonist rescues C/EBPα expression and restores SIK2 levels. CRTC2/3 promote insulin resistance via induction of the chemokines CXCL1/2. Knockout of CRTC2/3 in adipocytes reduces CXCL1/2 expression and improves insulin sensitivity. As administration of CXCL1/2 reverses salutary effects of CRTC2/3 depletion, our results demonstrate the importance of the CREB/CRTC pathway in modulating adipose tissue function.
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Affiliation(s)
- Young-Sil Yoon
- Peptide Biology Laboratories, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Weiyi Liu
- Peptide Biology Laboratories, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Sam Van de Velde
- Peptide Biology Laboratories, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Shigenobu Matsumura
- Department of Clinical Nutrition, Osaka Prefecture University, Habikino, Habikino City, Osaka, Japan
| | - Ezra Wiater
- Peptide Biology Laboratories, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Ling Huang
- The Razavi Newman Integrative Genomics and Bioinformatics Core, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Marc Montminy
- Peptide Biology Laboratories, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA.
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11
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The Small-Molecule Inhibitor MRIA9 Reveals Novel Insights into the Cell Cycle Roles of SIK2 in Ovarian Cancer Cells. Cancers (Basel) 2021; 13:cancers13153658. [PMID: 34359562 PMCID: PMC8345098 DOI: 10.3390/cancers13153658] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/07/2021] [Accepted: 07/14/2021] [Indexed: 01/17/2023] Open
Abstract
Simple Summary The current standard therapy of ovarian cancers comprises a reductive surgery followed by a combination of taxane-platinum-based primary chemotherapy. However, despite an initial positive response, patients in the advanced stage showed relapse within months or even weeks. Thus, there is a need to find combinatorial therapies that permit overcoming the paclitaxel-associated resistance in patients. Here, we found that MRIA9, a newly developed small-molecule inhibitor of the salt-inducible-kinase 2, interferes with the cell division of cancer cells. More importantly, MRIA9 increases paclitaxel efficiency in eliminating ovarian cancer cells and patient derived cancer cells by inducing apoptosis or programmed cell death. Thus, our study indicates that MRIA9 might represent a novel therapeutical tool for translational studies to overcome paclitaxel resistance in ovarian cancer. Abstract The activity of the Salt inducible kinase 2 (SIK2), a member of the AMP-activated protein kinase (AMPK)-related kinase family, has been linked to several biological processes that maintain cellular and energetic homeostasis. SIK2 is overexpressed in several cancers, including ovarian cancer, where it promotes the proliferation of metastases. Furthermore, as a centrosome kinase, SIK2 has been shown to regulate the G2/M transition, and its depletion sensitizes ovarian cancer to paclitaxel-based chemotherapy. Here, we report the consequences of SIK2 inhibition on mitosis and synergies with paclitaxel in ovarian cancer using a novel and selective inhibitor, MRIA9. We show that MRIA9-induced inhibition of SIK2 blocks the centrosome disjunction, impairs the centrosome alignment, and causes spindle mispositioning during mitosis. Furthermore, the inhibition of SIK2 using MRIA9 increases chromosomal instability, revealing the role of SIK2 in maintaining genomic stability. Finally, MRIA9 treatment enhances the sensitivity to paclitaxel in 3D-spheroids derived from ovarian cancer cell lines and ovarian cancer patients. Our study suggests selective targeting of SIK2 in ovarian cancer as a therapeutic strategy for overcoming paclitaxel resistance.
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12
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Shi M, Wang L, Li P, Liu J, Chen L, Xu D. Dasatinib-SIK2 Binding Elucidated by Homology Modeling, Molecular Docking, and Dynamics Simulations. ACS OMEGA 2021; 6:11025-11038. [PMID: 34056256 PMCID: PMC8153941 DOI: 10.1021/acsomega.1c00947] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 04/06/2021] [Indexed: 02/08/2023]
Abstract
![]()
Salt-inducible kinases
(SIKs) are calcium/calmodulin-dependent
protein kinase (CAMK)-like (CAMKL) family members implicated in insulin
signal transduction, metabolic regulation, inflammatory response,
and other processes. Here, we focused on SIK2, which is a target of
the Food and Drug Administration (FDA)-approved pan inhibitor N-(2-chloro-6-methylphenyl)-2-(6-(4-(2-hydroxyethyl)piperazin-1-yl)-2-methylpyrimidin-4-ylamino)thiazole-5-carboxamide
(dasatinib), and constructed four representative SIK2 structures by
homology modeling. We investigated the interactions between dasatinib
and SIK2 via molecular docking, molecular dynamics simulation, and
binding free energy calculation and found that dasatinib showed strong
binding affinity for SIK2. Binding free energy calculations suggested
that the modification of various dasatinib regions may provide useful
information for drug design and to guide the discovery of novel dasatinib-based
SIK2 inhibitors.
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Affiliation(s)
- Mingsong Shi
- State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Lun Wang
- State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Penghui Li
- MOE Key Laboratory of Green Chemistry and Technology, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Jiang Liu
- State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Lijuan Chen
- State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Dingguo Xu
- MOE Key Laboratory of Green Chemistry and Technology, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
- Research Center for Material Genome Engineering, Sichuan University, Chengdu, Sichuan 610065, China
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13
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Nuts and bolts of the salt-inducible kinases (SIKs). Biochem J 2021; 478:1377-1397. [PMID: 33861845 PMCID: PMC8057676 DOI: 10.1042/bcj20200502] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 12/24/2022]
Abstract
The salt-inducible kinases, SIK1, SIK2 and SIK3, most closely resemble the AMP-activated protein kinase (AMPK) and other AMPK-related kinases, and like these family members they require phosphorylation by LKB1 to be catalytically active. However, unlike other AMPK-related kinases they are phosphorylated by cyclic AMP-dependent protein kinase (PKA), which promotes their binding to 14-3-3 proteins and inactivation. The most well-established substrates of the SIKs are the CREB-regulated transcriptional co-activators (CRTCs), and the Class 2a histone deacetylases (HDAC4/5/7/9). Phosphorylation by SIKs promotes the translocation of CRTCs and Class 2a HDACs to the cytoplasm and their binding to 14-3-3s, preventing them from regulating their nuclear binding partners, the transcription factors CREB and MEF2. This process is reversed by PKA-dependent inactivation of the SIKs leading to dephosphorylation of CRTCs and Class 2a HDACs and their re-entry into the nucleus. Through the reversible regulation of these substrates and others that have not yet been identified, the SIKs regulate many physiological processes ranging from innate immunity, circadian rhythms and bone formation, to skin pigmentation and metabolism. This review summarises current knowledge of the SIKs and the evidence underpinning these findings, and discusses the therapeutic potential of SIK inhibitors for the treatment of disease.
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14
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Sun Z, Jiang Q, Li J, Guo J. The potent roles of salt-inducible kinases (SIKs) in metabolic homeostasis and tumorigenesis. Signal Transduct Target Ther 2020; 5:150. [PMID: 32788639 PMCID: PMC7423983 DOI: 10.1038/s41392-020-00265-w] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/22/2020] [Indexed: 01/26/2023] Open
Abstract
Salt-inducible kinases (SIKs) belong to AMP-activated protein kinase (AMPK) family, and functions mainly involve in regulating energy response-related physiological processes, such as gluconeogenesis and lipid metabolism. However, compared with another well-established energy-response kinase AMPK, SIK roles in human diseases, especially in diabetes and tumorigenesis, are rarely investigated. Recently, the pilot roles of SIKs in tumorigenesis have begun to attract more attention due to the finding that the tumor suppressor role of LKB1 in non-small-cell lung cancers (NSCLCs) is unexpectedly mediated by the SIK but not AMPK kinases. Thus, here we tend to comprehensively summarize the emerging upstream regulators, downstream substrates, mouse models, clinical relevance, and candidate inhibitors for SIKs, and shed light on SIKs as the potential therapeutic targets for cancer therapies.
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Affiliation(s)
- Zicheng Sun
- Institute of Precision Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, 510275, China.,Department of Breast and Thyroid Surgery, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, 510275, China
| | - Qiwei Jiang
- Institute of Precision Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, 510275, China
| | - Jie Li
- Department of Breast and Thyroid Surgery, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, 510275, China.
| | - Jianping Guo
- Institute of Precision Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, 510275, China.
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15
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Salt inducible kinases as novel Notch interactors in the developing Drosophila retina. PLoS One 2020; 15:e0234744. [PMID: 32542037 PMCID: PMC7295197 DOI: 10.1371/journal.pone.0234744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Accepted: 06/01/2020] [Indexed: 12/26/2022] Open
Abstract
Developmental processes require strict regulation of proliferation, differentiation and patterning for the generation of final organ size. Aberrations in these fundamental events are critically important in tumorigenesis and cancer progression. Salt inducible kinases (Siks) are evolutionarily conserved genes involved in diverse biological processes, including salt sensing, metabolism, muscle, cartilage and bone formation, but their role in development remains largely unknown. Recent findings implicate Siks in mitotic control, and in both tumor suppression and progression. Using a tumor model in the Drosophila eye, we show that perturbation of Sik function exacerbates tumor-like tissue overgrowth and metastasis. Furthermore, we show that both Drosophila Sik genes, Sik2 and Sik3, function in eye development processes. We propose that an important target of Siks may be the Notch signaling pathway, as we demonstrate genetic interaction between Siks and Notch pathway members. Finally, we investigate Sik expression in the developing retina and show that Sik2 is expressed in all photoreceptors, basal to cell junctions, while Sik3 appears to be expressed specifically in R3/R4 cells in the developing eye. Combined, our data suggest that Sik genes are important for eye tissue specification and growth, and that their dysregulation may contribute to tumor formation.
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16
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Zhao J, Zhang X, Gao T, Wang S, Hou Y, Yuan P, Yang Y, Yang T, Xing J, Li J, Liu S. SIK2 enhances synthesis of fatty acid and cholesterol in ovarian cancer cells and tumor growth through PI3K/Akt signaling pathway. Cell Death Dis 2020; 11:25. [PMID: 31932581 PMCID: PMC6957524 DOI: 10.1038/s41419-019-2221-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 12/19/2019] [Accepted: 12/20/2019] [Indexed: 12/15/2022]
Abstract
Salt-inducible kinase 2 (SIK2) has been established as a regulator of diverse biological processes including cell metabolism. A recent study has reported that SIK2 is required for adipocyte-induced ovarian cancer (OC) survival through facilitating fatty acid oxidation. However, whether SIK2 also plays a role in the lipid synthesis in OC cells remains elusive. Here, we showed that SIK2 significantly promoted the lipid synthesis in OC cells. On the one hand, SIK2 enhanced fatty acid synthesis through upregulating the expression of sterol regulatory element binding protein 1c (SREBP1c) and thus the transcription of major lipogenic enzyme FASN. On the other hand, SIK2 promoted cholesterol synthesis through upregulating the expression of sterol regulatory element binding protein 2 (SREBP2) and thus the transcription of major cholesterol synthesis enzymes HMGCR. Moreover, PI3K/Akt signaling pathway was found to be involved in the upregulation of SREBP1c and SREBP2 in OC cells. Moreover, in vitro and in vivo assays indicated that the SIK2-regulated fatty acid and cholesterol synthesis played a critical role in the growth of OC cells. Our findings demonstrate that SIK2 is a critical regulator of lipid synthesis in OC cells and thus promotes OC growth, which provides a strong line of evidence for this molecule to be used as a therapeutic target in the treatment of this malignancy.
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Affiliation(s)
- Jing Zhao
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China
| | - Xiaohong Zhang
- Department of Gynaecology and Obstetrics, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China
| | - Tian Gao
- Department of Gynaecology and Obstetrics, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China
| | - Shanci Wang
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastorenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yiran Hou
- Medical College of Yan'an University, Yan'an, Shaanxi, 716000, China
| | - Peng Yuan
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China
- Department of Pain Treatment, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, China
| | - Yi Yang
- Department of Pain Treatment, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, China
| | - Tao Yang
- Department of Pain Treatment, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, China
| | - Jinliang Xing
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China
| | - Jibin Li
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China.
- State Key Laboratory of Cancer Biology and Experimental Teaching Center of Basic Medicine, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China.
| | - Shujuan Liu
- Department of Gynaecology and Obstetrics, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710032, China.
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17
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SIK2 promotes reprogramming of glucose metabolism through PI3K/AKT/HIF-1α pathway and Drp1-mediated mitochondrial fission in ovarian cancer. Cancer Lett 2020; 469:89-101. [DOI: 10.1016/j.canlet.2019.10.029] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 10/15/2019] [Accepted: 10/17/2019] [Indexed: 01/01/2023]
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18
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Sirtuin 3-mediated pyruvate dehydrogenase activity determines brown adipocytes phenotype under high-salt conditions. Cell Death Dis 2019; 10:614. [PMID: 31409767 PMCID: PMC6692335 DOI: 10.1038/s41419-019-1834-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/07/2019] [Accepted: 07/23/2019] [Indexed: 11/10/2022]
Abstract
Previous study indicated that Sirtuin 3 (SIRT3) is a central regulator of adaptive thermogenesis in brown adipose tissue (BAT). Here we investigate the role of SIRT3 in the modulation of cellular phenotype in BAT under high salt intake (HS). HS downregulated SIRT3 level in BAT, accompanied by decreased oxygen consumption rate, and caused a severe loss of BAT characteristics. Mechanically, SIRT3 interacted with pyruvate dehydrogenase E1α (PDHA1) and deacetylated Lys-83 both in vitro and in vivo under HS. In parallel, HS suppressed salt-induced kinase (Sik) 2 phosphorylation. Silencing Sik2 further diminished SIRT3 activity and enhanced acetylation of PDHA1 K83 level. Reconstruction of SIRT3 restored PDH activity and thermogenic markers expression in differentiated brown adipocytes from SIRT3 knockout (KO) mice. In addition, loss of SIRT3 induced selective remodelling of phospholipids and glycerolipids in BAT exposure to HS. These data indicate that SIRT3 is an essential enzymatic switch that controls brown adipose cell phenotype.
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19
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Salt Inducible Kinase Signaling Networks: Implications for Acute Kidney Injury and Therapeutic Potential. Int J Mol Sci 2019; 20:ijms20133219. [PMID: 31262033 PMCID: PMC6651122 DOI: 10.3390/ijms20133219] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 06/26/2019] [Accepted: 06/27/2019] [Indexed: 02/06/2023] Open
Abstract
A number of signal transduction pathways are activated during Acute Kidney Injury (AKI). Of particular interest is the Salt Inducible Kinase (SIK) signaling network, and its effects on the Renal Proximal Tubule (RPT), one of the primary targets of injury in AKI. The SIK1 network is activated in the RPT following an increase in intracellular Na+ (Na+in), resulting in an increase in Na,K-ATPase activity, in addition to the phosphorylation of Class IIa Histone Deacetylases (HDACs). In addition, activated SIKs repress transcriptional regulation mediated by the interaction between cAMP Regulatory Element Binding Protein (CREB) and CREB Regulated Transcriptional Coactivators (CRTCs). Through their transcriptional effects, members of the SIK family regulate a number of metabolic processes, including such cellular processes regulated during AKI as fatty acid metabolism and mitochondrial biogenesis. SIKs are involved in regulating a number of other cellular events which occur during AKI, including apoptosis, the Epithelial to Mesenchymal Transition (EMT), and cell division. Recently, the different SIK kinase isoforms have emerged as promising drug targets, more than 20 new SIK2 inhibitors and activators having been identified by MALDI-TOF screening assays. Their implementation in the future should prove to be important in such renal disease states as AKI.
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20
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Insulin induces Thr484 phosphorylation and stabilization of SIK2 in adipocytes. Cell Signal 2019; 55:73-80. [DOI: 10.1016/j.cellsig.2018.12.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/20/2018] [Accepted: 12/21/2018] [Indexed: 11/17/2022]
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21
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Chen F, Chen L, Qin Q, Sun X. Salt-Inducible Kinase 2: An Oncogenic Signal Transmitter and Potential Target for Cancer Therapy. Front Oncol 2019; 9:18. [PMID: 30723708 PMCID: PMC6349817 DOI: 10.3389/fonc.2019.00018] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 01/07/2019] [Indexed: 12/15/2022] Open
Abstract
Salt-inducible kinase (SIK), which belongs to the sucrose non-fermenting 1/AMP-activated protein kinase family, was first discovered in the adrenal cortex of a rat on a high-salt diet. As an isoform of the SIK family, SIK2 modulates various biological functions and acts as a signal transmitter in various pathways. Compared with that in adjacent normal tissues, the expression of SIK2 is significantly higher in multiple types of tumors, which indicates its pivotal effect in oncogenesis. Studies on SIK2 have recently underlined its role in several signaling pathways, including the PI3K-Akt-mTOR pathway, the Hippo-YAP pathway, the LKB1-HDAC axis, and the cAMP-PKA axis. Moreover, a few small-molecule SIK2 inhibitors have been found to be able to rescue the oncogenicity of SIK2 during tumor development and reverse its abnormal activation of downstream pathways. In this mini-review, we discuss the results of in vivo and in vitro studies regarding the SIK2 mechanism in different signaling pathways, particularly their regulation of cancer cells. This work may provide new ideas for targeting SIK2 as a novel therapeutic strategy in tumor therapy.
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Affiliation(s)
- Fangyu Chen
- Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,The First School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Liuwei Chen
- The First School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Qin Qin
- Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xinchen Sun
- Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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22
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Sakamoto K, Bultot L, Göransson O. The Salt-Inducible Kinases: Emerging Metabolic Regulators. Trends Endocrinol Metab 2018; 29:827-840. [PMID: 30385008 DOI: 10.1016/j.tem.2018.09.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/18/2018] [Accepted: 09/27/2018] [Indexed: 01/08/2023]
Abstract
The discovery of liver kinase B1 (LKB1) as an upstream kinase for AMP-activated protein kinase (AMPK) led to the identification of several related kinases that also rely on LKB1 for their catalytic activity. Among these, the salt-inducible kinases (SIKs) have emerged as key regulators of metabolism. Unlike AMPK, SIKs do not respond to nucleotides, but their function is regulated by extracellular signals, such as hormones, through complex LKB1-independent mechanisms. While AMPK acts on multiple targets, including metabolic enzymes, to maintain cellular ATP levels, SIKs primarily regulate gene expression, by acting on transcriptional regulators, such as the cAMP response element-binding protein-regulated transcription coactivators and class IIa histone deacetylases. This review describes the development of research on SIKs, from their discovery to the most recent findings on metabolic regulation.
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Affiliation(s)
- Kei Sakamoto
- Nestlé Research, EPFL Innovation Park, Bâtiment G, 1015 Lausanne, Switzerland.
| | - Laurent Bultot
- Nestlé Research, EPFL Innovation Park, Bâtiment G, 1015 Lausanne, Switzerland; Current address: Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| | - Olga Göransson
- Department of Experimental Medical Science, Lund University, BMC C11, 221 84 Lund, Sweden.
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23
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Zhang Y, Takemori H, Wang C, Fu J, Xu M, Xiong L, Li N, Wen X. Role of salt inducible kinase 1 in high glucose-induced lipid accumulation in HepG2 cells and metformin intervention. Life Sci 2017; 173:107-115. [DOI: 10.1016/j.lfs.2017.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 01/21/2017] [Accepted: 02/02/2017] [Indexed: 01/14/2023]
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24
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Säll J, Pettersson AML, Björk C, Henriksson E, Wasserstrom S, Linder W, Zhou Y, Hansson O, Andersson DP, Ekelund M, Degerman E, Stenkula KG, Laurencikiene J, Göransson O. Salt-inducible kinase 2 and -3 are downregulated in adipose tissue from obese or insulin-resistant individuals: implications for insulin signalling and glucose uptake in human adipocytes. Diabetologia 2017; 60:314-323. [PMID: 27807598 PMCID: PMC6518086 DOI: 10.1007/s00125-016-4141-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 09/30/2016] [Indexed: 11/26/2022]
Abstract
AIMS/HYPOTHESIS Salt-inducible kinases (SIKs) are related to the metabolic regulator AMP-activated protein kinase (AMPK). SIK2 is abundant in adipose tissue. The aims of this study were to investigate the expression of SIKs in relation to human obesity and insulin resistance, and to evaluate whether changes in the expression of SIKs might play a causal role in the development of disturbed glucose uptake in human adipocytes. METHODS SIK mRNA and protein was determined in human adipose tissue or adipocytes, and correlated to clinical variables. SIK2 and SIK3 expression and phosphorylation were analysed in adipocytes treated with TNF-α. Glucose uptake, GLUT protein levels and localisation, phosphorylation of protein kinase B (PKB/Akt) and the SIK substrate histone deacetylase 4 (HDAC4) were analysed after the SIKs had been silenced using small interfering RNA (siRNA) or inhibited using a pan-SIK-inhibitor (HG-9-91-01). RESULTS We demonstrate that SIK2 and SIK3 mRNA are downregulated in adipose tissue from obese individuals and that the expression is regulated by weight change. SIK2 is also negatively associated with in vivo insulin resistance (HOMA-IR), independently of BMI and age. Moreover, SIK2 protein levels and specific kinase activity display a negative correlation to BMI in human adipocytes. Furthermore, SIK2 and SIK3 are downregulated by TNF-α in adipocytes. Silencing or inhibiting SIK1-3 in adipocytes results in reduced phosphorylation of HDAC4 and PKB/Akt, less GLUT4 at the plasma membrane, and lower basal and insulin-stimulated glucose uptake in adipocytes. CONCLUSION/INTERPRETATION This is the first study to describe the expression and function of SIKs in human adipocytes. Our data suggest that SIKs might be protective in the development of obesity-induced insulin resistance, with implications for future treatment strategies.
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Affiliation(s)
- Johanna Säll
- Protein Phosphorylation Research Group, Department of Experimental Medical Science, Lund University, BMC C11, Klinikgatan 28, 22242, Lund, Sweden
| | - Annie M L Pettersson
- Lipid Laboratory, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Christel Björk
- Lipid Laboratory, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Emma Henriksson
- Protein Phosphorylation Research Group, Department of Experimental Medical Science, Lund University, BMC C11, Klinikgatan 28, 22242, Lund, Sweden
| | - Sebastian Wasserstrom
- Glucose Transport and Protein Trafficking, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Wilhelm Linder
- Protein Phosphorylation Research Group, Department of Experimental Medical Science, Lund University, BMC C11, Klinikgatan 28, 22242, Lund, Sweden
| | - Yuedan Zhou
- Diabetes and Endocrinology, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
| | - Ola Hansson
- Diabetes and Endocrinology, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
| | - Daniel P Andersson
- Lipid Laboratory, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Mikael Ekelund
- Surgery, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Eva Degerman
- Insulin Signal Transduction, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Karin G Stenkula
- Glucose Transport and Protein Trafficking, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Jurga Laurencikiene
- Lipid Laboratory, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Olga Göransson
- Protein Phosphorylation Research Group, Department of Experimental Medical Science, Lund University, BMC C11, Klinikgatan 28, 22242, Lund, Sweden.
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25
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Miranda F, Mannion D, Liu S, Zheng Y, Mangala LS, Redondo C, Herrero-Gonzalez S, Xu R, Taylor C, Chedom DF, Carrami EM, Albukhari A, Jiang D, Pradeep S, Rodriguez-Aguayo C, Lopez-Berestein G, Salah E, Abdul Azeez KR, Elkins JM, Campo L, Myers KA, Klotz D, Bivona S, Dhar S, Bast RC, Saya H, Choi HG, Gray NS, Fischer R, Kessler BM, Yau C, Sood AK, Motohara T, Knapp S, Ahmed AA. Salt-Inducible Kinase 2 Couples Ovarian Cancer Cell Metabolism with Survival at the Adipocyte-Rich Metastatic Niche. Cancer Cell 2016; 30:273-289. [PMID: 27478041 DOI: 10.1016/j.ccell.2016.06.020] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 12/24/2015] [Accepted: 06/23/2016] [Indexed: 02/08/2023]
Abstract
The adipocyte-rich microenvironment forms a niche for ovarian cancer metastasis, but the mechanisms driving this process are incompletely understood. Here we show that salt-inducible kinase 2 (SIK2) is overexpressed in adipocyte-rich metastatic deposits compared with ovarian primary lesions. Overexpression of SIK2 in ovarian cancer cells promotes abdominal metastasis while SIK2 depletion prevents metastasis in vivo. Importantly, adipocytes induce calcium-dependent activation and autophosphorylation of SIK2. Activated SIK2 plays a dual role in augmenting AMPK-induced phosphorylation of acetyl-CoA carboxylase and in activating the PI3K/AKT pathway through p85α-S154 phosphorylation. These findings identify SIK2 at the apex of the adipocyte-induced signaling cascades in cancer cells and make a compelling case for targeting SIK2 for therapy in ovarian cancer.
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Affiliation(s)
- Fabrizio Miranda
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - David Mannion
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Shujuan Liu
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Yiyan Zheng
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Lingegowda S Mangala
- Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA; Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Clara Redondo
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK; Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK
| | - Sandra Herrero-Gonzalez
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Ruoyan Xu
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Charlotte Taylor
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Donatien Fotso Chedom
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Eli M Carrami
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Ashwag Albukhari
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK; Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21551, Saudi Arabia
| | - Dahai Jiang
- Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA; Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Sunila Pradeep
- Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Cristian Rodriguez-Aguayo
- Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA; Department of Experimental Therapeutics, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Gabriel Lopez-Berestein
- Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA; Department of Experimental Therapeutics, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Eidarus Salah
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK
| | - Kamal R Abdul Azeez
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK
| | - Jonathan M Elkins
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK
| | - Leticia Campo
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Kevin A Myers
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Daniel Klotz
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Serena Bivona
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Sunanda Dhar
- Department of Histopathology, Oxford University Hospitals, Oxford OX3 9DU, UK
| | - Robert C Bast
- Department of Experimental Therapeutics, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Hideyuki Saya
- Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, Tokyo 160-8582, Japan
| | - Hwan Geun Choi
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology, Dana Farber Cancer Institute, Boston, MA 02215, USA
| | - Nathanael S Gray
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology, Dana Farber Cancer Institute, Boston, MA 02215, USA
| | - Roman Fischer
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford OX3 7FZ, UK
| | - Benedikt M Kessler
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford OX3 7FZ, UK
| | - Christopher Yau
- Wellcome Trust Centre for Human Genetics, NIHR Biomedical Research Centre, Roosevelt Drive, Oxford OX3 7BN, UK; Department of Statistics, University of Oxford, 1 South Parks Road, Oxford OX1 3TG, UK
| | - Anil K Sood
- Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA; Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Takeshi Motohara
- Department of Obstetrics and Gynecology, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
| | - Stefan Knapp
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK; Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford OX3 7FZ, UK; Goethe-University Frankfurt, Institute for Pharmaceutical Chemistry and Buchmann Institute for Life Sciences, Riedberg Campus, 60438 Frankfurt am Main, Germany
| | - Ahmed Ashour Ahmed
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford OX3 9DS, UK; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK.
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26
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Henriksson E, Säll J, Gormand A, Wasserstrom S, Morrice NA, Fritzen AM, Foretz M, Campbell DG, Sakamoto K, Ekelund M, Degerman E, Stenkula KG, Göransson O. SIK2 regulates CRTCs, HDAC4 and glucose uptake in adipocytes. J Cell Sci 2016; 128:472-86. [PMID: 25472719 DOI: 10.1242/jcs.153932] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Salt-inducible kinase 2 (SIK2) is an AMP-activated protein kinase (AMPK) related kinase abundantly expressed in adipose tissue. Our aim was to identify molecular targets and functions of SIK2 in adipocytes, and to address the role of PKA-mediated phosphorylation of SIK2 on Ser358. Modulation of SIK2 in adipocytes resulted in altered phosphorylation of CREB-regulated transcription co-activator 2 (CRTC2), CRTC3 and class IIa histone deacetylase 4 (HDAC4). Furthermore, CRTC2, CRTC3, HDAC4 and protein phosphatase 2A (PP2A) interacted with SIK2, and the binding of CRTCs and PP2A to wild-type but not Ser358Ala SIK2, was reduced by cAMP elevation. Silencing of SIK2 resulted in reduced GLUT4 (also known as SLC2A4) protein levels, whereas cells treated with CRTC2 or HDAC4 siRNA displayed increased levels of GLUT4. Overexpression or pharmacological inhibition of SIK2 resulted in increased and decreased glucose uptake, respectively. We also describe a SIK2–CRTC2–HDAC4 pathway and its regulation in human adipocytes, strengthening the physiological relevance of our findings. Collectively, we demonstrate that SIK2 acts directly on CRTC2, CRTC3 and HDAC4, and that the cAMP–PKA pathway reduces the interaction of SIK2 with CRTCs and PP2A. Downstream, SIK2 increases GLUT4 levels and glucose uptake in adipocytes.
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27
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Yang H, Wang H. Signaling control of the constitutive androstane receptor (CAR). Protein Cell 2014; 5:113-23. [PMID: 24474196 PMCID: PMC3956974 DOI: 10.1007/s13238-013-0013-0] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Accepted: 12/07/2013] [Indexed: 01/30/2023] Open
Abstract
The constitutive androstane receptor (CAR, NR1I3) plays a crucial role in the regulation of drug metabolism, energy homeostasis, and cancer development through modulating the transcription of its numerous target genes. Different from prototypical nuclear receptors, CAR can be activated by either direct ligand binding or ligand-independent (indirect) mechanisms both initiated with nuclear translocation of CAR from the cytoplasm. In comparison to the well-defined ligand-based activation, indirect activation of CAR appears to be exclusively involved in the nuclear translocation through mechanisms yet to be fully understood. Accumulating evidence reveals that without activation, CAR forms a protein complex in the cytoplasm where it can be functionally affected by multiple signaling pathways. In this review, we discuss recent progresses in our understanding of the signaling regulation of CAR nuclear accumulation and activation. We expect that this review will also provide greater insight into the similarity and difference between the mechanisms of direct vs. indirect human CAR activation.
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Affiliation(s)
- Hui Yang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, MD, 21201, USA
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28
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Yu J, Hu X, Yang Z, Takemori H, Li Y, Zheng H, Hong S, Liao Q, Wen X. Salt-inducible kinase 1 is involved in high glucose-induced mesangial cell proliferation mediated by the ALK5 signaling pathway. Int J Mol Med 2013; 32:151-7. [PMID: 23670276 DOI: 10.3892/ijmm.2013.1377] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Accepted: 04/16/2013] [Indexed: 01/18/2023] Open
Abstract
High glucose levels can induce mesangial cell proliferation and extracellular matrix (ECM) accumulation through the type I activin receptor-like kinase 5 (ALK5) signaling pathway. Salt-inducible kinase 1 (SIK1) prevents fibrosis by downregulating ALK5, while the expression level of the SIK1 protein itself is downregulated by glucose in neuronal cells following ischemia. In this study, we investigated the correlation between SIK1 and the ALK5 signaling pathway in a rat glomerular mesangial cell line (HBZY-1 cells). We found that high glucose levels downregulated the expression level of SIK1 and suppressed the phosphorylation of SIK1 at Thr-182. The downregulation of SIK1 by high glucose was accompanied by the activation of the ALK5 signaling pathway, while the overexpression of SIK1 in the HBZY-1 cells resulted in a decrease in the ALK5 protein level, as well in the levels of its downstream targets, including fibronectin and plasminogen activator inhibitor type I. In conclusion, high glucose may activate the ALK5 signaling pathway by downregulating SIK1, and SIK1 may be a protective factor against cellular proliferation and ECM accumulation in glomerular mesangial cells under high glucose conditions.
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Affiliation(s)
- Jie Yu
- Department of Traditional Chinese Medicine and Endocrinology, Liyuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
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29
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Hoffmann BR, El-Mansy MF, Sem DS, Greene AS. Chemical proteomics-based analysis of off-target binding profiles for rosiglitazone and pioglitazone: clues for assessing potential for cardiotoxicity. J Med Chem 2012; 55:8260-71. [PMID: 22970990 PMCID: PMC4113394 DOI: 10.1021/jm301204r] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Drugs exert desired and undesired effects based on their binding interactions with protein target(s) and off-target(s), providing evidence for drug efficacy and toxicity. Pioglitazone and rosiglitazone possess a common functional core, glitazone, which is considered a privileged scaffold upon which to build a drug selective for a given target--in this case, PPARγ. Herein, we report a retrospective analysis of two variants of the glitazone scaffold, pioglitazone and rosiglitazone, in an effort to identify off-target binding events in the rat heart to explain recently reported cardiovascular risk associated with these drugs. Our results suggest that glitazone has affinity for dehydrogenases, consistent with known binding preferences for related rhodanine cores. Both drugs bound ion channels and modulators, with implications in congestive heart failure, arrhythmia, and peripheral edema. Additional proteins involved in glucose homeostasis, synaptic transduction, and mitochondrial energy production were detected and potentially contribute to drug efficacy and cardiotoxicity.
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Affiliation(s)
- Brian R. Hoffmann
- Biotechnology and Bioengineering Center, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Mohamed F. El-Mansy
- Chemical Proteomics Facility at Marquette, Department of Chemistry, Marquette University, Milwaukee, WI 53201
| | - Daniel S. Sem
- Chemical Proteomics Facility at Marquette, Department of Chemistry, Marquette University, Milwaukee, WI 53201
| | - Andrew S. Greene
- Biotechnology and Bioengineering Center, Medical College of Wisconsin, Milwaukee, WI 53226
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30
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Abstract
SIK2 (salt-inducible kinase 2) is a member of the AMPK (AMP-activated protein kinase) family of kinases and is highly expressed in adipocytes. We investigated the regulation of SIK2 in adipocytes in response to cellular stimuli with relevance for adipocyte function and/or AMPK signalling. None of the treatments, including insulin, cAMP inducers or AICAR (5-amino-4-imidazolecarboxamide riboside), affected SIK2 activity towards peptide or protein substrates in vitro. However, stimulation with the cAMP-elevating agent forskolin and the β-adrenergic receptor agonist CL 316,243 resulted in a PKA (protein kinase A)-dependent phosphorylation and 14-3-3 binding of SIK2. Phosphopeptide mapping of SIK2 revealed several sites phosphorylated in response to cAMP induction, including Ser358. Site-directed mutagenesis demonstrated that phosphorylation of Ser358, but not the previously reported PKA site Ser587, was required for 14-3-3 binding. Immunocytochemistry illustrated that the localization of exogenously expressed SIK2 in HEK (human embryonic kidney)-293 cells was exclusively cytosolic and remained unchanged after cAMP elevation. Fractionation of adipocytes, however, revealed a significant increase of wild-type, but not Ser358Ala, HA (haemagglutinin)–SIK2 in the cytosol and a concomitant decrease in a particulate fraction after CL 316,243 treatment. This supports a phosphorylation-dependent relocalization in adipocytes. We hypothesize that regulation of SIK2 by cAMP could play a role for the critical effects of this second messenger on lipid metabolism in adipocytes.
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31
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Havula E, Hietakangas V. Glucose sensing by ChREBP/MondoA-Mlx transcription factors. Semin Cell Dev Biol 2012; 23:640-7. [PMID: 22406740 DOI: 10.1016/j.semcdb.2012.02.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 02/24/2012] [Indexed: 01/02/2023]
Abstract
The paralogous transcription factors ChREBP and MondoA, together with their common binding partner Mlx, have emerged as key mediators of intracellular glucose sensing. By regulating target genes involved in glycolysis and lipogenesis, they mediate metabolic adaptation to changing glucose levels. As disturbed glucose homeostasis plays a central role in human metabolic diseases and as cancer cells often display altered glucose metabolism, better understanding of cellular glucose sensing will likely uncover new therapeutic opportunities. Here we review the regulation, function and evolutionary conservation of the ChREBP/MondoA-Mlx glucose sensing system and discuss possible directions for future research.
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Affiliation(s)
- Essi Havula
- Institute of Biotechnology, University of Helsinki, Viikinkaari 1, 00014 Helsinki, Finland
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32
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33
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Jaitovich A, Bertorello AM. Intracellular sodium sensing: SIK1 network, hormone action and high blood pressure. Biochim Biophys Acta Mol Basis Dis 2010; 1802:1140-9. [PMID: 20347966 DOI: 10.1016/j.bbadis.2010.03.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 03/12/2010] [Accepted: 03/20/2010] [Indexed: 01/11/2023]
Abstract
Sodium is the main determinant of body fluid distribution. Sodium accumulation causes water retention and, often, high blood pressure. At the cellular level, the concentration and active transport of sodium is handled by the enzyme Na(+),K(+)-ATPase, whose appearance enabled evolving primitive cells to cope with osmotic stress and contributed to the complexity of mammalian organisms. Na(+),K(+)-ATPase is a platform at the hub of many cellular signaling pathways related to sensing intracellular sodium and dealing with its detrimental excess. One of these pathways relies on an intracellular sodium-sensor network with the salt-inducible kinase 1 (SIK1) at its core. When intracellular sodium levels rise, and after the activation of calcium-related signals, this network activates the Na(+),K(+)-ATPase and expel the excess of sodium from the cytosol. The SIK1 network also mediates sodium-independent signals that modulate the activity of the Na(+),K(+)-ATPase, like dopamine and angiotensin, which are relevant per se in the development of high blood pressure. Animal models of high blood pressure, with identified mutations in components of multiple pathways, also have alterations in the SIK1 network. The introduction of some of these mutants into normal cells causes changes in SIK1 activity as well. Some cellular processes related to the metabolic syndrome, such as insulin effects on the kidney and other tissues, also appear to involve the SIK1. Therefore, it is likely that this protein, by modulating active sodium transport and numerous hormonal responses, represents a "crossroad" in the development and adaptation to high blood pressure and associated diseases.
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Affiliation(s)
- Ariel Jaitovich
- Department of Medicine, Karolinska Institutet, Karolinska University Hospital-Solna, 171 76 Stockholm, Sweden.
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34
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Muraoka M, Fukushima A, Viengchareun S, Lombès M, Kishi F, Miyauchi A, Kanematsu M, Doi J, Kajimura J, Nakai R, Uebi T, Okamoto M, Takemori H. Involvement of SIK2/TORC2 signaling cascade in the regulation of insulin-induced PGC-1alpha and UCP-1 gene expression in brown adipocytes. Am J Physiol Endocrinol Metab 2009; 296:E1430-9. [PMID: 19351809 DOI: 10.1152/ajpendo.00024.2009] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Salt-inducible kinase 2 (SIK2) is expressed abundantly in adipose tissues and represses cAMP-response element-binding protein (CREB)-mediated gene expression by phosphorylating the coactivator transducer of regulated CREB activity (TORC2). Phosphorylation at Ser(587) of SIK2 diminishes its TORC2 phosphorylation activity. In 3T3-L1 white adipocytes, SIK2 downregulates lipogenic gene in response to nutritional stresses. To investigate the impact of SIK2 on the function of brown adipose tissue (BAT), we used T37i brown adipocytes, mice with diet-induced obesity, and SIK2 mutant (S587A) transgenic mice. When T37i adipocytes were treated with insulin, the levels of peroxisome proliferator-activated receptor-coactivator-1alpha (PGC-1alpha) and uncoupling protein-1 (UCP-1) mRNA were increased, and the induction was inhibited by overexpression of SIK2 (S587A) mutant or dominant-negative CREB. Insulin enhanced SIK2 phosphorylation at Ser(587), which was accompanied by decrease in phospho-TORC2. Similarly, the decrease in the level of SIK2 phosphorylation at Ser(587) was observed in the BAT of mice with diet-induced obesity, which was negatively correlated with TORC2 phosphorylation. To confirm the negative correlation between SIK2 phosphorylation at Ser(587) and TORC2 phosphorylation in BAT, SIK2 mutant (S587A) was overexpressed in adipose tissues by using the adipocyte fatty acid-binding protein 2 promoter. The expression of recombinant SIK2 (S587A) was restricted to BAT, and the levels of phospho-TORC2 were elevated in BAT of transgenic mice. Male transgenic mice developed high-fat diet-induced obesity, and their BAT expressed low levels of PGC-1alpha and UCP-1 mRNA, suggesting that SIK2-TORC2 cascade may be important for the regulation of PGC-1alpha and UCP-1 gene expression in insulin signaling in BAT.
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Affiliation(s)
- Masaaki Muraoka
- Laboratory of Cell Signaling and Metabolism, National Institute of Biomedical Innovation, 7-6-8, Asagi, Saito, Ibaraki, Osaka 567-0085, Japan
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35
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Abstract
The AMP-activated serine/threonine protein kinase (AMPK) is a sensor of cellular energy status found in all eukaryotes that is activated under conditions of low intracellular ATP following stresses such as nutrient deprivation or hypoxia. In the past 5 years, work from a large number of laboratories has revealed that one of the major downstream signalling pathways regulated by AMPK is the mammalian target-of-rapamycin [mammalian target of rapamycin (mTOR) pathway]. Interestingly, like AMPK, the mTOR serine/threonine kinase plays key roles not only in growth control and cell proliferation but also in metabolism. Recent work has revealed that across eukaryotes mTOR orthologues are found in two biochemically distinct complexes and only one of those complexes (mTORC1 in mammals) is acutely sensitive to rapamycin and regulated by nutrients and AMPK. Many details of the molecular mechanism by which AMPK inhibits mTORC1 signalling have also been decoded in the past 5 years. AMPK directly phosphorylates at least two proteins to induce rapid suppression of mTORC1 activity, the TSC2 tumour suppressor and the critical mTORC1 binding subunit raptor. Here we explore the molecular connections between AMPK and mTOR signalling pathways and examine the physiological processes in which AMPK regulation of mTOR is critical for growth or metabolic control. The functional conservation of AMPK and TOR in all eukaryotes, and the sequence conservation around the AMPK phosphorylation sites in raptor across all eukaryotes examined suggest that this represents a fundamental cell growth module connecting nutrient status to the cell growth machinery. These findings have broad implications for the control of cell growth by nutrients in a number of cellular and organismal contexts.
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Affiliation(s)
- R J Shaw
- Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
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36
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Abstract
Insulin signaling at target tissues is essential for growth and development and for normal homeostasis of glucose, fat, and protein metabolism. Control over this process is therefore tightly regulated. It can be achieved by a negative feedback control mechanism whereby downstream components inhibit upstream elements along the insulin-signaling pathway (autoregulation) or by signals from apparently unrelated pathways that inhibit insulin signaling thus leading to insulin resistance. Phosphorylation of insulin receptor substrate (IRS) proteins on serine residues has emerged as a key step in these control processes under both physiological and pathological conditions. The list of IRS kinases implicated in the development of insulin resistance is growing rapidly, concomitant with the list of potential Ser/Thr phosphorylation sites in IRS proteins. Here, we review a range of conditions that activate IRS kinases to phosphorylate IRS proteins on "hot spot" domains. The flexibility vs. specificity features of this reaction is discussed and its characteristic as an "array" phosphorylation is suggested. Finally, its implications on insulin signaling, insulin resistance and type 2 diabetes, an emerging epidemic of the 21st century are outlined.
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Affiliation(s)
- Sigalit Boura-Halfon
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, 76100 Israel
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37
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Takemori H, Katoh Hashimoto Y, Nakae J, Olson EN, Okamoto M. Inactivation of HDAC5 by SIK1 in AICAR-treated C2C12 myoblasts. Endocr J 2009; 56:121-30. [PMID: 18946175 DOI: 10.1507/endocrj.k08e-173] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Salt inducible kinase (SIK) 1, a member of the AMP-activated kinase (AMPK) family, is activated by the AMPK-activator LKB1 which phosphorylates SIK1 at Thr182. The activated SIK1 then auto-phosphorylates its Ser186 located at the +4 position of Thr182. The phospho-Ser186 is essential for sustained activity of SIK1, which is maintained by sequential phosphorylation at Ser186-Thr182 by glycogen synthase kinase (GSK)-3beta. Meanwhile, SIK1 represses the transcription factor cAMP-response element binding protein (CREB) by phosphorylating its co-activator transducer of regulated CREB activity (TORC). Recently, histone deacetylase (HDAC) 5 was identified as a new substrate of SIK1. Inhibition of SIK1 or AMPK results in the stimulation of glyconeogensis in the liver by enhancing dephosphorylation of TORC2 followed by up-regulation of peroxisome proliferator-activated receptor coactivator (PGC)-1alpha gene expression. However, expression of the PGC-1alpha gene has been found to be repressed in LKB1-defective muscle cells. Our findings show that the AMPK agonist 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR)-dependent expression of PGC-1alpha is diminished by inhibitors of GSK-3beta or SIKs in C2C12 myoblasts. Treatment with AICAR or the overexpression of SIK1 induces nuclear export of HDAC5 followed by the activation of myogenic transcription factor (MEF)-2C. The levels of phosphorylation at Thr182 and Ser186 of SIK1 in AICAR-treated C2C12 cells are elevated, and GSK-3beta enzyme purified from AICAR-treated cells shows enhanced phosphorylation activity of SIK1 in vitro. These observations suggest that GSK-3 beta and SIK1 may play important roles in the regulation of PGC-1alpha gene expression by inactivating HDAC5 followed by activation of MEF2C.
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Affiliation(s)
- Hiroshi Takemori
- Laboratory of Cell Signaling and Metabolism, National Institute of Biomedical Innovation, Osaka, Japan
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Boura-Halfon S, Zick Y. Serine kinases of insulin receptor substrate proteins. VITAMINS AND HORMONES 2009; 80:313-49. [PMID: 19251043 DOI: 10.1016/s0083-6729(08)00612-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Signaling of insulin and insulin-like growth factor-I (IGF-1) at target tissues is essential for growth, development and for normal homeostasis of glucose, fat, and protein metabolism. Control over this process is therefore tightly regulated. It can be achieved by a negative-feedback control mechanism, whereby downstream components inhibit upstream elements along the insulin and IGF-1 signaling pathway or by signals from other pathways that inhibit insulin/IGF-1 signaling thus leading to insulin/IGF-1 resistance. Phosphorylation of insulin receptor substrates (IRS) proteins on serine residues has emerged as a key step in these control processes both under physiological and pathological conditions. The list of IRS kinases is growing rapidly, concomitant with the list of potential Ser/Thr phosphorylation sites in IRS proteins. Here we review a range of conditions that activate IRS kinases to phosphorylate IRS proteins on selected domains. The specificity of this reaction is discussed and its characteristic as an "array" phosphorylation is suggested. Finally, its implications on insulin/IGF-1 signaling, insulin/IGF-1 resistance and diabetes, an emerging epidemic of the twenty-first century are outlined.
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Affiliation(s)
- Sigalit Boura-Halfon
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
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