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Cha MH, Choi HJ, Ma JY. Lysophosphatidylcholines Promote Influenza Virus Reproduction through the MAPK/JNK Pathway in PMA-Differentiated THP-1 Macrophages. Int J Mol Sci 2024; 25:6538. [PMID: 38928244 PMCID: PMC11204278 DOI: 10.3390/ijms25126538] [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: 05/13/2024] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/28/2024] Open
Abstract
Obesity and metabolic syndrome alter serum lipid profiles. They also increase vulnerability to viral infections and worsen the survival rate and symptoms after infection. How serum lipids affect influenza virus proliferation is unclear. Here, we investigated the effects of lysophosphatidylcholines on influenza A virus (IAV) proliferation. IAV particles in the culture medium were titrated using extraction-free quantitative PCR, and viral RNA and protein levels were assessed using real-time PCR and Western blot, respectively. RNA sequencing data were analyzed using PCA and heatmap analysis, and pathway analysis was performed using the KEGG mapper and PathIN tools. Statistical analysis was conducted using SPSS21.0. LPC treatment of THP-1 cells significantly increased IAV proliferation and IAV RNA and protein levels, and saturated LPC was more active in IAV RNA expression than unsaturated LPC was. The functional analysis of genes affected by LPCs showed that the expression of genes involved in IAV signaling, such as suppressor of cytokine signaling 3 (SOCS3), phosphoinositide-3-kinase regulatory subunit 3 (PI3K) and AKT serine/threonine kinase 3 (AKT3), Toll-like receptor 7 (TKR7), and interferon gamma receptor 1 (IFNGR1), was changed by LPC. Altered influenza A pathways were linked with MAPK and PI3K/AKT signaling. Treatment with inhibitors of MAPK or PI3K attenuated viral gene expression changes induced by LPCs. The present study shows that LPCs stimulated virus reproduction by modifying the cellular environment to one in which viruses proliferated better. This was mediated by the MAPK, JNK, and PI3K/AKT pathways. Further animal studies are needed to confirm the link between LPCs from serum or the respiratory system and IAV proliferation.
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Affiliation(s)
- Min-Ho Cha
- Korean Medicine (KM) Application Center, Korea Institute of Oriental Medicine (KIOM), Daegu 41062, Republic of Korea;
| | | | - Jin-Yeul Ma
- Korean Medicine (KM) Application Center, Korea Institute of Oriental Medicine (KIOM), Daegu 41062, Republic of Korea;
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Zhou Q, Chen Y, Liang Y, Sun Y. The Role of Lysophospholipid Metabolites LPC and LPA in the Pathogenesis of Chronic Obstructive Pulmonary Disease. Metabolites 2024; 14:317. [PMID: 38921452 PMCID: PMC11205356 DOI: 10.3390/metabo14060317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 05/26/2024] [Accepted: 05/29/2024] [Indexed: 06/27/2024] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a heterogeneous lung condition characterized by persistent respiratory symptoms and airflow limitation. While there are some available treatment options, the effectiveness of treatment varies depending on individual differences and the phenotypes of the disease. Therefore, exploring or identifying potential therapeutic targets for COPD is urgently needed. In recent years, there has been growing evidence showing that lysophospholipids, namely lysophosphatidylcholine (LPC) and lysophosphatidic acid (LPA), can play a significant role in the pathogenesis of COPD. Exploring the metabolism of lysophospholipids holds promise for understanding the underlying mechanism of COPD development and developing novel strategies for COPD treatment. This review primarily concentrates on the involvement and signaling pathways of LPC and LPA in the development and progression of COPD. Furthermore, we reviewed their associations with clinical manifestations, phenotypes, and prognosis within the COPD context and discussed the potential of the pivotal signaling molecules as viable therapeutic targets for COPD treatment.
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Affiliation(s)
- Qiqiang Zhou
- Department of Respiratory and Critical Care Medicine, Peking University Third Hospital, Beijing 100191, China; (Q.Z.); (Y.C.); (Y.S.)
| | - Yahong Chen
- Department of Respiratory and Critical Care Medicine, Peking University Third Hospital, Beijing 100191, China; (Q.Z.); (Y.C.); (Y.S.)
- Research Center for Chronic Airway Diseases, Peking University Health Science Center, Beijing 100191, China
| | - Ying Liang
- Department of Respiratory and Critical Care Medicine, Peking University Third Hospital, Beijing 100191, China; (Q.Z.); (Y.C.); (Y.S.)
- Research Center for Chronic Airway Diseases, Peking University Health Science Center, Beijing 100191, China
| | - Yongchang Sun
- Department of Respiratory and Critical Care Medicine, Peking University Third Hospital, Beijing 100191, China; (Q.Z.); (Y.C.); (Y.S.)
- Research Center for Chronic Airway Diseases, Peking University Health Science Center, Beijing 100191, China
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Cui B, Liu Y, Chen J, Chen H, Feng Y, Zhang P. Small molecule inhibitor CRT0066101 inhibits cytokine storm syndrome in a mouse model of lung injury. Int Immunopharmacol 2023; 120:110240. [PMID: 37182445 PMCID: PMC10181585 DOI: 10.1016/j.intimp.2023.110240] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/08/2023] [Accepted: 04/22/2023] [Indexed: 05/16/2023]
Abstract
Pneumonia is an acute inflammation of the lungs induced by pathogenic microorganisms, immune damage, physical and chemical factors, and other factors, and the latest outbreak of novel coronavirus pneumonia is also an acute lung injury (ALI) induced by viral infection. However, there are currently no effective treatments for inflammatory cytokine storms in patients with ALI/acute respiratory distress syndrome (ARDS). Protein kinase D (PKD) is a highly active kinase that has been shown to be associated with the production of inflammatory cytokines. Therefore, small-molecule compounds that inhibit PKD may be potential drugs for the treatment of ALI/ARDS. In the present study, we evaluated the ability of the small-molecule inhibitor CRT0066101 to attenuate lipopolysaccharide (LPS)-induced inflammatory cytokine production through in vitro cell experiments and a mouse pneumonia model. We found that CRT0066101 significantly reduced the protein and mRNA levels of LPS-induced cytokines (e.g., IL-6, TNF-α, and IL-1β). CRT0066101 inhibited MyD88 and TLR4 expression and reduced NF-κB, ERK, and JNK phosphorylation. CRT0066101 also reduced NLRP3 activation, inhibited the assembly of the inflammasome complex, and attenuated inflammatory cell infiltration and lung tissue damage. Taken together, our data indicate that CRT0066101 exerts anti-inflammatory effects on LPS-induced inflammation through the TLR4/MyD88 signaling pathway, suggesting that CRT0066101 may have therapeutic value in acute lung injury and other MyD88-dependent inflammatory diseases.
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Affiliation(s)
- Bomiao Cui
- State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, 14, Renmin South Road Section 3, Chengdu, Sichuan 610041, PR China
| | - Yiying Liu
- State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, 14, Renmin South Road Section 3, Chengdu, Sichuan 610041, PR China
| | - Jiao Chen
- State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, 14, Renmin South Road Section 3, Chengdu, Sichuan 610041, PR China
| | - Hongli Chen
- State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, 14, Renmin South Road Section 3, Chengdu, Sichuan 610041, PR China
| | - Yun Feng
- State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, 14, Renmin South Road Section 3, Chengdu, Sichuan 610041, PR China
| | - Ping Zhang
- State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, 14, Renmin South Road Section 3, Chengdu, Sichuan 610041, PR China.
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Downregulation of activating transcription factor 4 attenuates lysophosphatidycholine-induced inflammation via the NF-κB pathway. Eur J Pharmacol 2021; 911:174457. [PMID: 34582847 DOI: 10.1016/j.ejphar.2021.174457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 07/29/2021] [Accepted: 08/26/2021] [Indexed: 11/20/2022]
Abstract
Lysophosphatidycholine (LPC) is the main active component in oxidized low-density lipoprotein (ox-LDL). The pathological function of ox-LDL has been broadly studied in atherosclerosis. However, the specific relationship between LPC-induced unfolded protein response (UPR) and inflammation in human umbilical vein endothelial cells (HUVECs) remains elusive. In this study, we found elevated serum levels of LPC in atherosclerotic patients. LPC stimulation resulted in elevated secretion of interleukin (IL)-6 and IL-8 in HUVECs, accompanied with the activation of ER stress and NF-κB pathway. Additionally, suppression of ER stress by 4-phenylbutric acid (4-PBA), an ER stress inhibitor, alleviated the activation of the NF-κB pathway and secretion of inflammatory factors. Moreover, activating transcription factor 4 (ATF4) silencing inhibited the transcription and secretion of IL-6 and IL-8, and suppressed the adhesion of THP-1 cells to HUVECs. Activation of the NF-κB pathway and expression of its upstream factors, including Toll like receptor 4 and cellular inhibitor of apoptosis, were also inhibited by ATF4 silencing. The present findings suggest that suppression of UPR alleviates LPC-induced HUVECs inflammation by inhibition of NF-κB pathway, and indicate ATF4 as a potential target for the treatment of atherosclerosis.
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Wang Y, Wu J, Zhu J, Ding C, Xu W, Hao H, Zhang J, Wang G, Cao L. Ginsenosides regulation of lysophosphatidylcholine profiles underlies the mechanism of Shengmai Yin in attenuating atherosclerosis. JOURNAL OF ETHNOPHARMACOLOGY 2021; 277:114223. [PMID: 34044080 DOI: 10.1016/j.jep.2021.114223] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 05/13/2021] [Accepted: 05/19/2021] [Indexed: 06/12/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The traditional Chinese medicine (TCM) preparation, Shengmai Yin (SMY), is widely applied in cardiovascular disease treatments. However, the pharmacological mechanism of its therapeutic effects has not been fully clarified. AIM OF THIS STUDY This study aimed to clearly define the efficacy and underlying mechanism of SMY and its active components in protecting against atherosclerosis. MATERIALS AND METHODS The pharmacological effects of SMY and its components were evaluated upon a mouse hypercholesteremia model induced by a high cholesterol diet (HCD) for 12 weeks and Apoe-/- mice, a mouse atherosclerosis model. Pathological indicators including serum cholesterol levels, cytokines and histological changes in aortic root plaques were assessed. Untargeted metabolomic, untargeted lipidomic and targeted lipidomic changing profiles were investigated to clarify pharmacological mechanisms. RESULTS SMY and red ginseng crude extracts (GE) significantly decreased the serum cholesterol levels in hypercholesteremia mice and reduced the aortic root plaque areas and exerted antiatherogenic efficacy in Apoe-/- mice. Moreover, total red ginseng saponin extracts (TGS) showed the most apparent improvement on maintaining lipid homeostasis, representing the effects of red ginseng in SMY on atherosclerosis treatment. Mechanically, TGS inhibited serum secreted phospholipase A2 (sPLA2) activity and lowered the serum levels of lysophosphatidylcholine (lysoPC), which is a risk factor for atherosclerosis. CONCLUSIONS Our findings revealed that ginsenosides from SMY exerted therapeutic effects on atherosclerosis by maintaining lipid homeostasis including cholesterol and lysoPCs.
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Affiliation(s)
- Yun Wang
- State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China.
| | - Jiawei Wu
- State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China.
| | - Jiaying Zhu
- State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China.
| | - Chujie Ding
- State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China.
| | - Wanfeng Xu
- State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China.
| | - Haiping Hao
- State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China.
| | - Jun Zhang
- School of Pharmacy, Nanjing Medical University, Nanjing, China.
| | - Guangji Wang
- State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China.
| | - Lijuan Cao
- State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China.
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Hao F, Liu Q, Zhang F, Du J, Dumire A, Xu X, Cui MZ. LPA 1-mediated PKD2 activation promotes LPA-induced tissue factor expression via the p38α and JNK2 MAPK pathways in smooth muscle cells. J Biol Chem 2021; 297:101152. [PMID: 34478715 PMCID: PMC8502912 DOI: 10.1016/j.jbc.2021.101152] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 08/20/2021] [Accepted: 08/30/2021] [Indexed: 11/26/2022] Open
Abstract
Tissue factor (TF) is the principal initiator of blood coagulation and is necessary for thrombosis. We previously reported that lysophosphatidic acid (LPA), a potent bioactive lipid, highly induces TF expression at the transcriptional level in vascular smooth muscle cells. To date, however, the specific role of the LPA receptor is unknown, and the intracellular signaling pathways that lead to LPA induction of TF have been largely undetermined. In the current study, we found that LPA markedly induced protein kinase D (PKD) activation in mouse aortic smooth muscle cells (MASMCs). Small-interfering RNA-mediated knockdown of PKD2 blocked LPA-induced TF expression and activity, indicating that PKD2 is the key intracellular mediator of LPA signaling leading to the expression and cell surface activity of TF. Furthermore, our data reveal a novel finding that PKD2 mediates LPA-induced TF expression via the p38α and JNK2 MAPK signaling pathways, which are accompanied by the PKD-independent MEK1/2-ERK-JNK pathway. To identify the LPA receptor(s) responsible for LPA-induced TF expression, we isolated MASMCs from LPA receptor-knockout mice. Our results demonstrated that SMCs isolated from LPA receptor 1 (LPA1)-deficient mice completely lost responsiveness to LPA stimulation, which mediates induction of TF expression and activation of PKD and p38/JNK MAPK, indicating that LPA1 is responsible for PKD2-mediated activation of JNK2 and p38α. Taken together, our data reveal a new signaling mechanism in which the LPA1-PKD2 axis mediates LPA-induced TF expression via the p38α and JNK2 pathways. This finding provides new insights into LPA signaling, the PKD2 pathway, and the mechanisms of coagulation/atherothrombosis.
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Affiliation(s)
- Feng Hao
- Department of Biology, College of Arts and Sciences, University of Texas Permian Basin, Odessa, Texas, USA
| | - Qiwei Liu
- Department of Biology, College of Arts and Sciences, University of Texas Permian Basin, Odessa, Texas, USA; Department of Cardiology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Fuqiang Zhang
- Science and Research Center, China-Japan Union Hospital, Jilin University, Changchun, China
| | - Jiaxin Du
- Department of Biology, College of Arts and Sciences, University of Texas Permian Basin, Odessa, Texas, USA
| | - Amanda Dumire
- Department of Biology, College of Arts and Sciences, University of Texas Permian Basin, Odessa, Texas, USA
| | - Xuemin Xu
- Department of Biology, College of Arts and Sciences, University of Texas Permian Basin, Odessa, Texas, USA
| | - Mei-Zhen Cui
- Department of Biology, College of Arts and Sciences, University of Texas Permian Basin, Odessa, Texas, USA.
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7
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Ooi GJ, Meikle PJ, Huynh K, Earnest A, Roberts SK, Kemp W, Parker BL, Brown W, Burton P, Watt MJ. Hepatic lipidomic remodeling in severe obesity manifests with steatosis and does not evolve with non-alcoholic steatohepatitis. J Hepatol 2021; 75:524-535. [PMID: 33887358 DOI: 10.1016/j.jhep.2021.04.013] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 04/03/2021] [Accepted: 04/07/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUNDS & AIMS Obesity often leads to non-alcoholic fatty liver disease (NAFLD), which can progress from simple steatosis (non-alcoholic fatty liver (NAFL)) to non-alcoholic steatohepatitis (NASH). The accumulation of certain lipid subtypes is linked with worsening metabolic and liver disease, however, specific changes during progression from No-NAFL to NAFL then NASH are unresolved. Herein, we characterise the liver, adipose tissue and plasma lipidome of worsening NAFLD in obesity, and evaluate the utility of plasma lipids as biomarkers of NAFLD. METHODS Venous blood, liver, visceral and subcutaneous adipose tissue samples were obtained from 181 patients undergoing bariatric surgery. NAFLD severity was assessed histologically. Lipidomic analysis was performed using liquid chromatography-tandem mass spectrometry. RESULTS The liver lipidome showed substantial changes with increasing steatosis, with increased triacylglycerols, diacylglycerols and sphingolipids including ceramide, dihydroceramide, hexosyl-ceramide and GM3 ganglioside species. These lipid species were also increased in plasma with increasing hepatic steatosis and showed strong correlations with liver lipids. Adipose tissue lipidomes showed no correlation with NAFLD. There were no significant changes in liver lipids with NASH compared to NAFL. The addition of plasma lipid variables to routine markers yielded significant improvements in diagnostic accuracy for NASH (AUROC 0.667 vs. 0.785, p = 0.025). CONCLUSION Overall, these data provide a detailed description of the lipidomic changes with worsening NAFLD, showing significant changes with steatosis but no additional changes with NASH. Alterations in the liver lipidome are paralleled by similar changes in plasma. Further investigation is warranted into the potential utility of plasma lipids as non-invasive biomarkers of NAFLD in obesity. LAY SUMMARY Non-alcoholic fatty liver disease (NAFLD) is characterised by distinct changes in the liver lipidome with steatosis. The development of non-alcoholic steatohepatitis (NASH) does not result in further changes in the lipidome. Lipids within body fat do not appear to influence the lipid profile of the liver or blood. Changes in liver lipids are paralleled by changes in blood lipids. This has potential to be developed into a non-invasive biomarker for NAFLD. CLINICAL TRIAL NUMBER ACTRN12615000875505.
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Affiliation(s)
- Geraldine J Ooi
- Centre for Obesity Research and Education, Department of Surgery, Monash University, Melbourne, Victoria 3004, Australia.
| | - Peter J Meikle
- Baker Heart and Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Kevin Huynh
- Baker Heart and Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Arul Earnest
- Department of Epidemiology and Preventative Medicine, School of Public Health and Preventative Medicine, Monash University, Melbourne, Victoria 3004, Australia
| | - Stuart K Roberts
- Department of Gastroenterology, The Alfred Hospital and Monash University, Melbourne, Victoria, 3181, Australia
| | - William Kemp
- Department of Gastroenterology, The Alfred Hospital and Monash University, Melbourne, Victoria, 3181, Australia
| | - Benjamin L Parker
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Wendy Brown
- Centre for Obesity Research and Education, Department of Surgery, Monash University, Melbourne, Victoria 3004, Australia
| | - Paul Burton
- Centre for Obesity Research and Education, Department of Surgery, Monash University, Melbourne, Victoria 3004, Australia
| | - Matthew J Watt
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Victoria 3010, Australia.
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Li Q, Feng C, Li L, Xu G, Gu H, Li S, Li D, Liu M, Han S, Zheng B. Lipid Receptor G2A-Mediated Signal Pathway Plays a Critical Role in Inflammatory Response by Promoting Classical Macrophage Activation. THE JOURNAL OF IMMUNOLOGY 2021; 206:2338-2352. [PMID: 33941654 DOI: 10.4049/jimmunol.2000231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 03/16/2021] [Indexed: 12/16/2022]
Abstract
Macrophage polarization is a dynamic and integral process in tissue inflammation and remodeling. In this study, we describe that lipoprotein-associated phospholipase A2 (Lp-PLA2) plays an important role in controlling inflammatory macrophage (M1) polarization in rodent experimental autoimmune encephalomyelitis (EAE) and in monocytes from multiple sclerosis (MS) patients. Specific inhibition of Lp-PLA2 led to an ameliorated EAE via markedly decreased inflammatory and demyelinating property of M1. The effects of Lp-PLA2 on M1 function were mediated by lysophosphatidylcholine, a bioactive product of oxidized lipids hydrolyzed by Lp-PLA2 through JAK2-independent activation of STAT5 and upregulation of IRF5. This process was directed by the G2A receptor, which was only found in differentiated M1 or monocytes from MS patients. M1 polarization could be inhibited by a G2A neutralizing Ab, which led to an inhibited disease in rat EAE. In addition, G2A-deficient rats showed an ameliorated EAE and an inhibited autoimmune response. This study has revealed a mechanism by which lipid metabolites control macrophage activation and function, modification of which could lead to a new therapeutic approach for MS and other inflammatory disorders.
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Affiliation(s)
- Qing Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and
| | - Chunlei Feng
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and
| | - Lingyun Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and
| | - Guiliang Xu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and
| | - Haijuan Gu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and
| | - Shiqiang Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and
| | - Dali Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and
| | - Mingyao Liu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and
| | - Shuhua Han
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX
| | - Biao Zheng
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China; and .,Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX
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9
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Li X, Nakayama K, Goto T, Akamatsu S, Kobayashi T, Shimizu K, Ogawa O, Inoue T. A narrative review of urinary phospholipids: from biochemical aspect towards clinical application. Transl Androl Urol 2021; 10:1829-1849. [PMID: 33968673 PMCID: PMC8100843 DOI: 10.21037/tau-20-1263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
As a newly emerged discipline, lipidomic studies have focused on the comprehensive characterization and quantification of lipids in a given biological system, which has remarkably advanced in recent years owing to the rapid development of analytical techniques, especially mass spectrometry. Among diverse lipid classes, phospholipids, which have fundamental roles in the formation of cellular membranes, signaling processes, and bioenergetics have gained momentum in several fields of research. The altered composition, concentration, spatial distribution, and metabolism of phospholipids in cells, tissues, and body fluids have been elucidated in various human diseases such as cancer, inflammation, as well as cardiovascular and metabolic disorders. Among the different kinds of phospholipid sources in the human body, urine has not been extensively investigated in recent years owing to the extremely low concentrations of phospholipids and high levels of salts and other contaminants, which can interfere with precise detection. However, with profound advances and rapid expansion in analytical methods, urinary phospholipids have attracted increasing attention in current biomedical research as urine is an easily available source for the discovery of noninvasive biomarkers. In this review, we provide an overview of urinary phospholipids, including their biochemical aspects and clinical applications, aimed at promoting this field of research.
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Affiliation(s)
- Xin Li
- Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Kenji Nakayama
- Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takayuki Goto
- Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Shusuke Akamatsu
- Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takashi Kobayashi
- Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Koji Shimizu
- Clinical Research Center for Medical Equipment Development, Kyoto University Hospital, Kyoto, Japan
| | - Osamu Ogawa
- Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takahiro Inoue
- Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, Tsu, Japan
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10
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Zhang X, Connelly J, Chao Y, Wang QJ. Multifaceted Functions of Protein Kinase D in Pathological Processes and Human Diseases. Biomolecules 2021; 11:biom11030483. [PMID: 33807058 PMCID: PMC8005150 DOI: 10.3390/biom11030483] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/13/2021] [Accepted: 03/15/2021] [Indexed: 02/06/2023] Open
Abstract
Protein kinase D (PKD) is a family of serine/threonine protein kinases operating in the signaling network of the second messenger diacylglycerol. The three family members, PKD1, PKD2, and PKD3, are activated by a variety of extracellular stimuli and transduce cell signals affecting many aspects of basic cell functions including secretion, migration, proliferation, survival, angiogenesis, and immune response. Dysregulation of PKD in expression and activity has been detected in many human diseases. Further loss- or gain-of-function studies at cellular levels and in animal models provide strong support for crucial roles of PKD in many pathological conditions, including cancer, metabolic disorders, cardiac diseases, central nervous system disorders, inflammatory diseases, and immune dysregulation. Complexity in enzymatic regulation and function is evident as PKD isoforms may act differently in different biological systems and disease models, and understanding the molecular mechanisms underlying these differences and their biological significance in vivo is essential for the development of safer and more effective PKD-targeted therapies. In this review, to provide a global understanding of PKD function, we present an overview of the PKD family in several major human diseases with more focus on cancer-associated biological processes.
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11
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Wang J, Dong X, Ma F, Li C, Bu R, Lu J, Gao J, Xue P. Metabolomics profiling reveals Echinops latifolius Tausch improves the trabecular micro-architecture of ovariectomized rats mainly via intervening amino acids and glycerophospholipids metabolism. JOURNAL OF ETHNOPHARMACOLOGY 2020; 260:113018. [PMID: 32502650 DOI: 10.1016/j.jep.2020.113018] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/22/2020] [Accepted: 05/24/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Echinops latifolius Tausch (ELT) is traditional Mongolian medicine in China, and often used to against osteoporosis, strengthen tendons and bones, clear bones heat. AIM OF THE STUDY To study efficacy of ELT on ovariectomized (OVX) rats and underly metabolic pathways related to trabecular micro-architecture changing of OVX. MATERIALS AND METHODS Three-month-old female Wistar rats were randomly divided into 4 groups (n = 6) including normal group (without surgery), sham group (bilateral laparotomy), OVX group (bilateral ovariectomy), and ELT-treated groups (ELT-treated after bilateral ovariectomy). The effects of ELT on trabecular micro-architecture and biochemical markers of OVX rat were investigated by dual-energy X-ray absorptiometry machine and Enzyme-linked immunosorbent assay (ELISA), respectively. Untargeted metabolomics strategy was applied to discover the potential biomarkers and related metabolic pathways involving the progression of OVX-induced osteoporosis. RESULTS The trabecular micro-architecture and biochemical markers of OVX rats were improved by ELT. We found 36 potential biomarkers and 21 related metabolic pathways were involved in progression of OVX-induced osteoporosis. Amino acids metabolism and glycerophospholipids metabolism were mainly intervened in ELT treatment on ovariectomized rats. The disordered amino acids and glycerophospholipids metabolism closely related to the imbalance between bone resorption and formation were reversed by administration of ELT, indicating that the influences of ELT on OVX rats' trabecular micro-architecture may possible be associated with intervening amino acids and glycerophospholipids metabolism. CONCLUSIONS This approach may provide the metabolomic perspective to link metabolic alterations and anti-osteoporosis action of ELT, to further explain how ELT works in postmenopausal patients with bone loss.
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Affiliation(s)
- Jiaqi Wang
- Department of Pharmacy, Inner Mongolia Medical University, Jinshan Development Zone, Hohhot, 010110, China
| | - Xin Dong
- Department of Pharmacy, Inner Mongolia Medical University, Jinshan Development Zone, Hohhot, 010110, China
| | - Feixiang Ma
- Department of Pharmacy, Inner Mongolia Medical University, Jinshan Development Zone, Hohhot, 010110, China
| | - Chunyan Li
- Department of Pharmacy, Inner Mongolia Medical University, Jinshan Development Zone, Hohhot, 010110, China
| | - Ren Bu
- Department of Pharmacy, Inner Mongolia Medical University, Jinshan Development Zone, Hohhot, 010110, China
| | - Jingkun Lu
- Department of Pharmacy, Inner Mongolia Medical University, Jinshan Development Zone, Hohhot, 010110, China
| | - Jianping Gao
- Department of Pharmacy, Inner Mongolia Medical University, Jinshan Development Zone, Hohhot, 010110, China.
| | - Peifeng Xue
- Department of Pharmacy, Inner Mongolia Medical University, Jinshan Development Zone, Hohhot, 010110, China.
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12
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Liu P, Zhu W, Chen C, Yan B, Zhu L, Chen X, Peng C. The mechanisms of lysophosphatidylcholine in the development of diseases. Life Sci 2020; 247:117443. [DOI: 10.1016/j.lfs.2020.117443] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/11/2020] [Accepted: 02/17/2020] [Indexed: 02/07/2023]
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13
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Qiu C, Yu F, Su K, Zhao Q, Zhang L, Xu C, Hu W, Wang Z, Zhao L, Tian Q, Wang Y, Deng H, Shen H. Multi-omics Data Integration for Identifying Osteoporosis Biomarkers and Their Biological Interaction and Causal Mechanisms. iScience 2020; 23:100847. [PMID: 32058959 PMCID: PMC6997862 DOI: 10.1016/j.isci.2020.100847] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 11/22/2019] [Accepted: 01/13/2020] [Indexed: 12/31/2022] Open
Abstract
Osteoporosis is characterized by low bone mineral density (BMD). The advancement of high-throughput technologies and integrative approaches provided an opportunity for deciphering the mechanisms underlying osteoporosis. Here, we generated genomic, transcriptomic, methylomic, and metabolomic datasets from 119 subjects with high (n = 61) and low (n = 58) BMDs. By adopting sparse multiple discriminative canonical correlation analysis, we identified an optimal multi-omics biomarker panel with 74 differentially expressed genes (DEGs), 75 differentially methylated CpG sites (DMCs), and 23 differential metabolic products (DMPs). By linking genetic data, we identified 199 targeted BMD-associated expression/methylation/metabolite quantitative trait loci (eQTLs/meQTLs/metaQTLs). The reconstructed networks/pathways showed extensive biomarker interactions, and a substantial proportion of these biomarkers were enriched in RANK/RANKL, MAPK/TGF-β, and WNT/β-catenin pathways and G-protein-coupled receptor, GTP-binding/GTPase, telomere/mitochondrial activities that are essential for bone metabolism. Five biomarkers (FADS2, ADRA2A, FMN1, RABL2A, SPRY1) revealed causal effects on BMD variation. Our study provided an innovative framework and insights into the pathogenesis of osteoporosis.
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Affiliation(s)
- Chuan Qiu
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA
| | - Fangtang Yu
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA
| | - Kuanjui Su
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA
| | - Qi Zhao
- Department of Preventive Medicine, College of Medicine, University of Tennessee Health Science Center, Memphis 38163, TN, USA
| | - Lan Zhang
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA
| | - Chao Xu
- Department of Biostatistics and Epidemiology, University of Oklahoma Health Sciences Center, Oklahoma City 73104, OK, USA
| | - Wenxing Hu
- Department of Biomedical Engineering, Tulane University, New Orleans 70118, LA, USA
| | - Zun Wang
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA; Xiangya Nursing School, Central South University, Changsha 410013, China
| | - Lanjuan Zhao
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA
| | - Qing Tian
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA
| | - Yuping Wang
- Department of Biomedical Engineering, Tulane University, New Orleans 70118, LA, USA
| | - Hongwen Deng
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA; School of Basic Medical Science, Central South University, Changsha 410013, China
| | - Hui Shen
- Center for Bioinformatics and Genomics, Department of Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans 70112, LA, USA.
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14
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Matsumura K, Baba M, Nagayasu K, Yamamoto K, Kondo M, Kitagawa K, Takemoto T, Seiriki K, Kasai A, Ago Y, Hayata-Takano A, Shintani N, Kuriu T, Iguchi T, Sato M, Takuma K, Hashimoto R, Hashimoto H, Nakazawa T. Autism-associated protein kinase D2 regulates embryonic cortical neuron development. Biochem Biophys Res Commun 2019; 519:626-632. [PMID: 31540692 DOI: 10.1016/j.bbrc.2019.09.048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 09/12/2019] [Indexed: 12/26/2022]
Abstract
Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder, characterized by impaired social interaction, repetitive behavior and restricted interests. Although the molecular etiology of ASD remains largely unknown, recent studies have suggested that de novo mutations are significantly involved in the risk of ASD. We and others recently identified spontaneous de novo mutations in PKD2, a protein kinase D family member, in sporadic ASD cases. However, the biological significance of the de novo PKD2 mutations and the role of PKD2 in brain development remain unclear. Here, we performed functional analysis of PKD2 in cortical neuron development using in utero electroporation. PKD2 is highly expressed in cortical neural stem cells in the developing cortex and regulates cortical neuron development, including the neuronal differentiation of neural stem cells and migration of newborn neurons. Importantly, we determined that the ASD-associated de novo mutations impair the kinase activity of PKD2, suggesting that the de novo PKD2 mutations can be a risk factor for the disease by loss of function of PKD2. Our current findings provide novel insight into the molecular and cellular pathogenesis of ASD.
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Affiliation(s)
- Kensuke Matsumura
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan; Interdisciplinary Program for Biomedical Sciences, Institute for Transdisciplinary Graduate Degree Programs, Osaka University, Suita, Osaka, 565-0871, Japan; Research Fellowships for Young Scientists of the Japan Society for the Promotion of Science, Chiyoda-ku, Tokyo, 102-0083, Japan
| | - Masayuki Baba
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Kazuki Nagayasu
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Kana Yamamoto
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Momoka Kondo
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Kohei Kitagawa
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Tomoya Takemoto
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Kaoru Seiriki
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan; Interdisciplinary Program for Biomedical Sciences, Institute for Transdisciplinary Graduate Degree Programs, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Atsushi Kasai
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Yukio Ago
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan; Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Atsuko Hayata-Takano
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan; United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Suita, Osaka, 565-0871, Japan
| | - Norihito Shintani
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Toshihiko Kuriu
- Osaka Medical College, Research and Development Center, Takatsuki, Osaka, 569-8686, Japan
| | - Tokuichi Iguchi
- Department of Anatomy and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Makoto Sato
- United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Suita, Osaka, 565-0871, Japan; Department of Anatomy and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka, 565-0871, Japan; Research Center for Child Mental Development, University of Fukui, Yoshida-gun, Fukui, 910-1193, Japan
| | - Kazuhiro Takuma
- United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Suita, Osaka, 565-0871, Japan; Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Ryota Hashimoto
- Department of Pathology of Mental Diseases, National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Tokyo, 187-8553, Japan; Osaka University, Suita, Osaka, 565-0871, Japan
| | - Hitoshi Hashimoto
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan; United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Suita, Osaka, 565-0871, Japan; Division of Bioscience, Institute for Datability Science, Osaka University, Suita, Osaka, 565-0871, Japan; Transdimensional Life Imaging Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Osaka, 565-0871, Japan; Department of Molecular Pharmaceutical Science, Graduate School of Medicine, Osaka University, Suita, Osaka, 565-0871, Japan.
| | - Takanobu Nakazawa
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, 565-0871, Japan; Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, 565-0871, Japan.
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15
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Law SH, Chan ML, Marathe GK, Parveen F, Chen CH, Ke LY. An Updated Review of Lysophosphatidylcholine Metabolism in Human Diseases. Int J Mol Sci 2019; 20:ijms20051149. [PMID: 30845751 PMCID: PMC6429061 DOI: 10.3390/ijms20051149] [Citation(s) in RCA: 392] [Impact Index Per Article: 78.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 02/27/2019] [Accepted: 02/28/2019] [Indexed: 12/12/2022] Open
Abstract
Lysophosphatidylcholine (LPC) is increasingly recognized as a key marker/factor positively associated with cardiovascular and neurodegenerative diseases. However, findings from recent clinical lipidomic studies of LPC have been controversial. A key issue is the complexity of the enzymatic cascade involved in LPC metabolism. Here, we address the coordination of these enzymes and the derangement that may disrupt LPC homeostasis, leading to metabolic disorders. LPC is mainly derived from the turnover of phosphatidylcholine (PC) in the circulation by phospholipase A2 (PLA2). In the presence of Acyl-CoA, lysophosphatidylcholine acyltransferase (LPCAT) converts LPC to PC, which rapidly gets recycled by the Lands cycle. However, overexpression or enhanced activity of PLA2 increases the LPC content in modified low-density lipoprotein (LDL) and oxidized LDL, which play significant roles in the development of atherosclerotic plaques and endothelial dysfunction. The intracellular enzyme LPCAT cannot directly remove LPC from circulation. Hydrolysis of LPC by autotaxin, an enzyme with lysophospholipase D activity, generates lysophosphatidic acid, which is highly associated with cancers. Although enzymes with lysophospholipase A1 activity could theoretically degrade LPC into harmless metabolites, they have not been found in the circulation. In conclusion, understanding enzyme kinetics and LPC metabolism may help identify novel therapeutic targets in LPC-associated diseases.
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Affiliation(s)
- Shi-Hui Law
- Department of Medical Laboratory Science and Biotechnology, College of Health Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
| | - Mei-Lin Chan
- Center for Lipid Biosciences, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan.
- Division of Thoracic Surgery, Department of Surgery, MacKay Memorial Hospital, MacKay Medical College, Taipei 10449, Taiwan.
| | - Gopal K Marathe
- Department of Studies in Biochemistry, Manasagangothri, University of Mysore, Mysore-570006, India.
| | - Farzana Parveen
- Department of Medical Laboratory Science and Biotechnology, College of Health Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
| | - Chu-Huang Chen
- Center for Lipid Biosciences, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan.
- Lipid Science and Aging Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
- Vascular and Medicinal Research, Texas Heart Institute, Houston, TX 77030, USA.
| | - Liang-Yin Ke
- Department of Medical Laboratory Science and Biotechnology, College of Health Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
- Center for Lipid Biosciences, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan.
- Lipid Science and Aging Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
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16
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Kim MY. [The Progression of Liver Fibrosis in Non-alcoholic Fatty Liver Disease]. THE KOREAN JOURNAL OF GASTROENTEROLOGY 2018. [PMID: 28637102 DOI: 10.4166/kjg.2017.69.6.341] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Understanding the pathogenesis of non-alcoholic steatohepatitis (NASH) and its fibrosis progression is still evolving. Nonetheless, current evidence suggests that mechanisms involved are very complex parallel processes with multiple metabolic factors. Lipotoxicity related with excess saturated free fatty acids, obesity, and insulin resistance acts as the central driver of cellular injury via oxidative stress. Hepatocyte apoptosis and/or senescence are also contribute to the activation of inflammasome via various intra- and inter-cellular signaling mechanisms that lead to fibrosis. Current evidence suggests that periportal components, including ductular reaction and expansion of the hepatic progenitor cell compartment, may be involved and that the T-helper 17 cell response may mediate disease progression. This review aims to provide a brief overview of the pathogenesis of NASH and fibrosis progression from inflammation to fibrosis.
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Affiliation(s)
- Moon Young Kim
- Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea
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17
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Tomin T, Fritz K, Gindlhuber J, Waldherr L, Pucher B, Thallinger GG, Nomura DK, Schittmayer M, Birner-Gruenberger R. Deletion of Adipose Triglyceride Lipase Links Triacylglycerol Accumulation to a More-Aggressive Phenotype in A549 Lung Carcinoma Cells. J Proteome Res 2018; 17:1415-1425. [PMID: 29457907 DOI: 10.1021/acs.jproteome.7b00782] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Adipose triglyceride lipase (ATGL) catalyzes the rate limiting step in triacylglycerol breakdown in adipocytes but is expressed in most tissues. The enzyme was shown to be lost in many human tumors, and its loss may play a role in early stages of cancer development. Here, we report that loss of ATGL supports a more-aggressive cancer phenotype in a model system in which ATGL was deleted in A549 lung cancer cells by CRISPR/Cas9. We observed that loss of ATGL led to triacylglycerol accumulation in lipid droplets and higher levels of cellular phospholipid and bioactive lipid species (lyso- and ether-phospholipids). Label-free quantitative proteomics revealed elevated expression of the pro-oncogene SRC kinase in ATGL depleted cells, which was also found on mRNA level and confirmed on protein level by Western blot. Consistently, higher expression of phosphorylated (active) SRC (Y416 phospho-SRC) was observed in ATGL-KO cells. Cells depleted of ATGL migrated faster, which was dependent on SRC kinase activity. We propose that loss of ATGL may thus increase cancer aggressiveness by activation of pro-oncogenic signaling via SRC kinase and increased levels of bioactive lipids.
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Affiliation(s)
- Tamara Tomin
- Research Unit Functional Proteomics and Metabolic Pathways , Institute of Pathology, Medical University of Graz , 8010 Graz , Austria.,Omics Center Graz, BioTechMed-Graz , 8010 Graz , Austria
| | - Katarina Fritz
- Research Unit Functional Proteomics and Metabolic Pathways , Institute of Pathology, Medical University of Graz , 8010 Graz , Austria.,Omics Center Graz, BioTechMed-Graz , 8010 Graz , Austria
| | - Juergen Gindlhuber
- Research Unit Functional Proteomics and Metabolic Pathways , Institute of Pathology, Medical University of Graz , 8010 Graz , Austria.,Omics Center Graz, BioTechMed-Graz , 8010 Graz , Austria
| | - Linda Waldherr
- Research Unit Functional Proteomics and Metabolic Pathways , Institute of Pathology, Medical University of Graz , 8010 Graz , Austria.,Omics Center Graz, BioTechMed-Graz , 8010 Graz , Austria
| | - Bettina Pucher
- Omics Center Graz, BioTechMed-Graz , 8010 Graz , Austria.,Institute of Computational Biotechnology, Graz University of Technology , 8010 Graz , Austria
| | - Gerhard G Thallinger
- Omics Center Graz, BioTechMed-Graz , 8010 Graz , Austria.,Institute of Computational Biotechnology, Graz University of Technology , 8010 Graz , Austria
| | | | - Matthias Schittmayer
- Research Unit Functional Proteomics and Metabolic Pathways , Institute of Pathology, Medical University of Graz , 8010 Graz , Austria.,Omics Center Graz, BioTechMed-Graz , 8010 Graz , Austria
| | - Ruth Birner-Gruenberger
- Research Unit Functional Proteomics and Metabolic Pathways , Institute of Pathology, Medical University of Graz , 8010 Graz , Austria.,Omics Center Graz, BioTechMed-Graz , 8010 Graz , Austria
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18
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Chen X, Chen H, Dai M, Ai J, Li Y, Mahon B, Dai S, Deng Y. Plasma lipidomics profiling identified lipid biomarkers in distinguishing early-stage breast cancer from benign lesions. Oncotarget 2017; 7:36622-36631. [PMID: 27153558 PMCID: PMC5095026 DOI: 10.18632/oncotarget.9124] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 04/16/2016] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Breast cancer is very common and highly fatal in women. Current non-invasive detection methods like mammograms are unsatisfactory. Lipidomics, a promising detection method, may serve as a novel prognostic approach for breast cancer in high-risk patients. RESULTS According the predictive model, the combination of 15 lipid species had high diagnostic value. In the training set, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the combination of these 15 lipid species were 83.3%, 92.7%, 89.7%, and 87.9%, respectively. The AUC in the training set was 0.926 (95% CI 0.869-0.982). Similar results were found in the validation set, with the sensitivity, specificity, PPV and NPV at 81.0%, 94.5%, 91.9%, and 86.7%, respectively. The AUC was 0.938 (95% CI 0.889-0.986) in the validation set. METHODS Using triple quadrupole liquid chromatography electrospray ionization tandem mass spectrometry, this study was to detect global lipid profiling of a total of 194 plasma samples from 84 patients with early-stage breast cancer (stage 0-II) and 110 patients with benign breast disease included in a training set and a validation set. A binary logistic regression was used to build a predictive model for evaluating the lipid species as potential biomarkers in the diagnosis of breast cancer. CONCLUSIONS The combination of these 15 lipid species as a panel could be used as plasma biomarkers for the diagnosis of breast cancer.
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Affiliation(s)
- Xiaoli Chen
- Department of Clinical Laboratory, The Fourth Hospital Affiliated to Guangxi Medical University, Liuzhou City, Guangxi Province, China.,Department of Medicine, Rush University Medical Center, Chicago, Illinois, USA
| | - Hankui Chen
- Department of Medicine, Rush University Medical Center, Chicago, Illinois, USA
| | - Meiyu Dai
- Department of Clinical Laboratory, The Fourth Hospital Affiliated to Guangxi Medical University, Liuzhou City, Guangxi Province, China.,Department of Medicine, Rush University Medical Center, Chicago, Illinois, USA
| | - Junmei Ai
- Department of Medicine, Rush University Medical Center, Chicago, Illinois, USA
| | - Yan Li
- Department of Medicine, Rush University Medical Center, Chicago, Illinois, USA
| | - Brett Mahon
- Department of Pathology, Rush University Medical Center, Chicago, Illinois, USA
| | - Shengming Dai
- Department of Clinical Laboratory, The Fourth Hospital Affiliated to Guangxi Medical University, Liuzhou City, Guangxi Province, China
| | - Youping Deng
- Department of Medicine, Rush University Medical Center, Chicago, Illinois, USA.,Department of Anatomy and Cell Biology, Rush University Medical Center, Chicago, Illinois, USA.,Medical College, Wuhan University of Science and Technology, Wuhan, Hubei Province, China
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19
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Plastira I, Bernhart E, Goeritzer M, DeVaney T, Reicher H, Hammer A, Lohberger B, Wintersperger A, Zucol B, Graier WF, Kratky D, Malle E, Sattler W. Lysophosphatidic acid via LPA-receptor 5/protein kinase D-dependent pathways induces a motile and pro-inflammatory microglial phenotype. J Neuroinflammation 2017; 14:253. [PMID: 29258556 PMCID: PMC5735906 DOI: 10.1186/s12974-017-1024-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 12/06/2017] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Extracellular lysophosphatidic acid (LPA) species transmit signals via six different G protein-coupled receptors (LPAR1-6) and are indispensible for brain development and function of the nervous system. However, under neuroinflammatory conditions or brain damage, LPA levels increase, thereby inducing signaling cascades that counteract brain function. We describe a critical role for 1-oleyl-2-hydroxy-sn-glycero-3-phosphate (termed "LPA" throughout our study) in mediating a motile and pro-inflammatory microglial phenotype via LPAR5 that couples to protein kinase D (PKD)-mediated pathways. METHODS Using the xCELLigence system and time-lapse microscopy, we investigated the migrational response of microglial cells. Different M1 and M2 markers were analyzed by confocal microscopy, flow cytometry, and immunoblotting. Using qPCR and ELISA, we studied the expression of migratory genes and quantitated the secretion of pro-inflammatory cytokines and chemokines, respectively. Different transcription factors that promote the regulation of pro-inflammatory genes were analyzed by western blot. Reactive oxygen species (ROS) and nitric oxide (NO) production, phagocytosis, and microglial cytotoxicity were determined using commercially available assay kits. RESULTS LPA induces MAPK family and AKT activation and pro-inflammatory transcription factors' phosphorylation (NF-κB, c-Jun, STAT1, and STAT3) that were inhibited by both LPAR5 and PKD family antagonists. LPA increases migratory capacity, induces secretion of pro-inflammatory cytokines and chemokines and expression of M1 markers, enhances production of ROS and NO by microglia, and augments cytotoxicity of microglial cell-conditioned medium towards neurons. The PKD family inhibitor blunted all of these effects. We propose that interference with this signaling axis could aid in the development of new therapeutic approaches to control neuroinflammation under conditions of overshooting LPA production. CONCLUSIONS In the present study, we show that inflammatory LPA levels increased the migratory response of microglia and promoted a pro-inflammatory phenotype via the LPAR5/PKD axis. Interference with this signaling axis reduced microglial migration, blunted microglial cytotoxicity, and abrogated the expression and secretion of pro-inflammatory mediators.
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Affiliation(s)
- I. Plastira
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - E. Bernhart
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - M. Goeritzer
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed-Graz, Graz, Austria
| | - T. DeVaney
- 0000 0000 8988 2476grid.11598.34Institute of Biophysics, Medical University of Graz, Graz, Austria
| | - H. Reicher
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - A. Hammer
- 0000 0000 8988 2476grid.11598.34Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - B. Lohberger
- 0000 0000 8988 2476grid.11598.34Department of Orthopedic Surgery, Medical University of Graz, Graz, Austria
| | - A. Wintersperger
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - B. Zucol
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - W. F. Graier
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed-Graz, Graz, Austria
| | - D. Kratky
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed-Graz, Graz, Austria
| | - E. Malle
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - W. Sattler
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed-Graz, Graz, Austria
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20
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Fernández-Sanlés A, Sayols-Baixeras S, Subirana I, Degano IR, Elosua R. Association between DNA methylation and coronary heart disease or other atherosclerotic events: A systematic review. Atherosclerosis 2017; 263:325-333. [PMID: 28577936 DOI: 10.1016/j.atherosclerosis.2017.05.022] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 04/05/2017] [Accepted: 05/17/2017] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND AIMS The aim of this study was to perform a systematic review of the association between DNA methylation and coronary heart disease (CHD) or related atherosclerotic traits. METHODS A systematic review was designed. The condition of interest was DNA methylation, and the outcome was CHD or other atherosclerosis-related traits. Three DNA methylation approaches were considered: global methylation, candidate-gene, and epigenome-wide association studies (EWAS). A functional analysis was undertaken using the Ingenuity Pathway Analysis software. RESULTS In total, 51 articles were included in the analysis: 12 global methylation, 34 candidate-gene and 11 EWAS, with six studies using more than one approach. The results of the global methylation studies were inconsistent. The candidate-gene results were consistent for some genes, suggesting that hypermethylation in ESRα, ABCG1 and FOXP3 and hypomethylation in IL-6 were associated with CHD. The EWAS identified 84 genes showing differential methylation associated with CHD in more than one study. The probability of these findings was <1.37·10-5. One third of these genes have been related to obesity in genome-wide association studies. The functional analysis identified several diseases and functions related to these set of genes: inflammatory, metabolic and cardiovascular disease. CONCLUSIONS Global DNA methylation seems to be not associated with CHD. The evidence from candidate-gene studies was limited. The EWAS identified a set of 84 genes highlighting the relevance of obesity, inflammation, lipid and carbohydrate metabolism in CHD. This set of genes could be prioritized in future studies assessing the role of DNA methylation in CHD.
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Affiliation(s)
- Alba Fernández-Sanlés
- Cardiovascular Epidemiology and Genetics Research Group, REGICOR Study Group, IMIM (Hospital Del Mar Medical Research Institute), Barcelona, Catalonia, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain
| | - Sergi Sayols-Baixeras
- Cardiovascular Epidemiology and Genetics Research Group, REGICOR Study Group, IMIM (Hospital Del Mar Medical Research Institute), Barcelona, Catalonia, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain; CIBER Cardiovascular Diseases (CIBERCV), Barcelona, Catalonia, Spain
| | - Isaac Subirana
- Cardiovascular Epidemiology and Genetics Research Group, REGICOR Study Group, IMIM (Hospital Del Mar Medical Research Institute), Barcelona, Catalonia, Spain; CIBER Epidemiology and Public Health (CIBERESP), Barcelona, Catalonia, Spain
| | - Irene R Degano
- Cardiovascular Epidemiology and Genetics Research Group, REGICOR Study Group, IMIM (Hospital Del Mar Medical Research Institute), Barcelona, Catalonia, Spain; CIBER Cardiovascular Diseases (CIBERCV), Barcelona, Catalonia, Spain
| | - Roberto Elosua
- Cardiovascular Epidemiology and Genetics Research Group, REGICOR Study Group, IMIM (Hospital Del Mar Medical Research Institute), Barcelona, Catalonia, Spain; CIBER Cardiovascular Diseases (CIBERCV), Barcelona, Catalonia, Spain.
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21
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Li X, Fang P, Yang WY, Chan K, Lavallee M, Xu K, Gao T, Wang H, Yang X. Mitochondrial ROS, uncoupled from ATP synthesis, determine endothelial activation for both physiological recruitment of patrolling cells and pathological recruitment of inflammatory cells. Can J Physiol Pharmacol 2016; 95:247-252. [PMID: 27925481 DOI: 10.1139/cjpp-2016-0515] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Mitochondrial reactive oxygen species (mtROS) are signaling molecules, which drive inflammatory cytokine production and T cell activation. In addition, cardiovascular diseases, cancers, and autoimmune diseases all share a common feature of increased mtROS level. Both mtROS and ATP are produced as a result of electron transport chain activity, but it remains enigmatic whether mtROS could be generated independently from ATP synthesis. A recent study shed light on this important question and found that, during endothelial cell (EC) activation, mtROS could be upregulated in a proton leak-coupled, but ATP synthesis-uncoupled manner. As a result, EC could upregulate mtROS production for physiological EC activation without compromising mitochondrial membrane potential and ATP generation, and consequently without causing mitochondrial damage and EC death. Thus, a novel pathophysiological role of proton leak in driving mtROS production was uncovered for low grade EC activation, patrolling immunosurveillance cell trans-endothelial migration and other signaling events without compromising cellular survival. This new working model explains how mtROS could be increasingly generated independently from ATP synthesis and endothelial damage or death. Mapping the connections among mitochondrial metabolism, physiological EC activation, patrolling cell migration, and pathological inflammation is significant towards the development of novel therapies for inflammatory diseases and cancers.
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Affiliation(s)
- Xinyuan Li
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Pu Fang
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - William Y Yang
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Kylie Chan
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Muriel Lavallee
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Keman Xu
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Tracy Gao
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Hong Wang
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Xiaofeng Yang
- Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Centers for Metabolic Disease Research, Cardiovascular Research, and Thrombosis Research, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
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22
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Protein Kinase D2 Protects against Acute Colitis Induced by Dextran Sulfate Sodium in Mice. Sci Rep 2016; 6:34079. [PMID: 27659202 PMCID: PMC5034322 DOI: 10.1038/srep34079] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 09/07/2016] [Indexed: 12/11/2022] Open
Abstract
Inflammatory bowel disease is characterized by dysregulation of the mucosal immune system resulting from impaired intestinal epithelial barrier function. Protein kinase D2 has been implicated in the regulation of immune responses. The present study was to define PKD2 might affect murine colitis. Colitis was induced in wild-type mice (PKD2WT/WT) and PKD2 catalytic activity deficient mice (PKD2SSAA/SSAA) with dextran sulfate sodium. PKD2SSAA-knockin mice displayed catalytic activity deficiency and increased susceptibility to DSS-induced colitis with enhanced weight loss, colonic inflammation compared with PKD2WT/WT mice. Furthermore, crucial inflammatory cytokines mRNA levels in PKD2SSAA-knockin mice were higher than controls accompanied with down-regulation of ZO-1, MUC2 and intestinal barrier dysfunction. However, there were no differences in the proliferation or apoptosis of intestinal epithelial cells in PKD2SSAA-knockin mice compared with wild-type controls. In addition, PKD2 expression was repressed in patients with IBD compared with healthy controls. These studies suggested that activation of PKD2 in the colonic epithelium microenvironment may contribute to protect against DSS-induced colitis through regulation of intestinal mucosal immunity and barrier function.
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23
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Lysophospholipid Receptors, as Novel Conditional Danger Receptors and Homeostatic Receptors Modulate Inflammation-Novel Paradigm and Therapeutic Potential. J Cardiovasc Transl Res 2016; 9:343-59. [PMID: 27230673 DOI: 10.1007/s12265-016-9700-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/19/2016] [Indexed: 12/29/2022]
Abstract
There are limitations in the current classification of danger-associated molecular patterns (DAMP) receptors. To overcome these limitations, we propose a new paradigm by using endogenous metabolites lysophospholipids (LPLs) as a prototype. By utilizing a data mining method we pioneered, we made the following findings: (1) endogenous metabolites such as LPLs at basal level have physiological functions; (2) under sterile inflammation, expression of some LPLs is elevated. These LPLs act as conditional DAMPs or anti-inflammatory homeostasis-associated molecular pattern molecules (HAMPs) for regulating the progression of inflammation or inhibition of inflammation, respectively; (3) receptors for conditional DAMPs and HAMPs are differentially expressed in human and mouse tissues; and (4) complex signaling mechanism exists between pro-inflammatory mediators and classical DAMPs that regulate the expression of conditional DAMPs and HAMPs. This novel insight will facilitate identification of novel conditional DAMPs and HAMPs, thus promote development of new therapeutic targets to treat inflammatory disorders.
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24
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Li YF, Li RS, Samuel SB, Cueto R, Li XY, Wang H, Yang XF. Lysophospholipids and their G protein-coupled receptors in atherosclerosis. Front Biosci (Landmark Ed) 2016; 21:70-88. [PMID: 26594106 DOI: 10.2741/4377] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Lysophospholipids (LPLs) are bioactive lipid-derived signaling molecules generated by the enzymatic and chemical processes of regiospecific phospholipases on substrates such as membrane phospholipids (PLs) and sphingolipids (SLs). They play a major role as extracellular mediators by activating G-protein coupled receptors (GPCRs) and stimulating diverse cellular responses from their signaling pathways. LPLs are involved in various pathologies of the vasculature system including coronary heart disease and hypertension. Many studies suggest the importance of LPLs in their association with the development of atherosclerosis, a chronic and severe vascular disease. This paper focuses on the pathophysiological effects of different lysophospholipids on atherosclerosis, which may promote the pathogenesis of myocardial infarction and strokes. Their atherogenic biological activities take place in vascular endothelial cells, vascular smooth muscle cells, fibroblasts, monocytes and macrophages, dendritic cells, T-lymphocytes, platelets, etc.
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Affiliation(s)
- Ya-Feng Li
- Centers for Metabolic Disease Research, Cardiovascular Research and Thrombosis Research, Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA 19140, USA ; Department of Nephrology and Hemodialysis Center, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, China
| | - Rong-Shan Li
- Department of Nephrology and Hemodialysis Center, Shanxi Provincial People's Hospital, Taiyuan, Shanxi 030012, China
| | - Sonia B Samuel
- Centers for Metabolic Disease Research, Cardiovascular Research and Thrombosis Research, Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Ramon Cueto
- Centers for Metabolic Disease Research, Cardiovascular Research and Thrombosis Research, Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Xin-Yuan Li
- Centers for Metabolic Disease Research, Cardiovascular Research and Thrombosis Research, Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Hong Wang
- Centers for Metabolic Disease Research, Cardiovascular Research and Thrombosis Research, Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Xiao-Feng Yang
- Centers for Metabolic Disease Research, Cardiovascular Research and Thrombosis Research, Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA 19140, USA
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25
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Durand N, Borges S, Storz P. Functional and therapeutic significance of protein kinase D enzymes in invasive breast cancer. Cell Mol Life Sci 2015; 72:4369-82. [PMID: 26253275 DOI: 10.1007/s00018-015-2011-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 07/30/2015] [Accepted: 08/03/2015] [Indexed: 12/31/2022]
Abstract
The protein kinase D (PKD) family members, PKD1, PKD2 and PKD3 constitute a family of serine/threonine kinases that are essential regulators of cell migration, proliferation and protein transport. Multiple types of cancers are characterized by aberrant expression of PKD isoforms. In breast cancer PKD isoforms exhibit distinct expression patterns and regulate various oncogenic processes. In highly invasive breast cancer, the leading cause of cancer-associated deaths in females, the loss of PKD1 is thought to promote invasion and metastasis, while PKD2 and upregulated PKD3 have been shown to be positive regulators of proliferation, chemoresistance and metastasis. In this review, we examine the differential expression pattern, mechanisms of regulation and contributions made by each PKD isoform to the development and maintenance of invasive breast cancer. In addition, we discuss the potential therapeutic approaches for targeting PKD in this disease.
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Affiliation(s)
- Nisha Durand
- Department of Cancer Biology, Mayo Clinic, Griffin Room 306, 4500 San Pablo Road, Jacksonville, FL, 32224, USA
| | - Sahra Borges
- Department of Cancer Biology, Mayo Clinic, Griffin Room 306, 4500 San Pablo Road, Jacksonville, FL, 32224, USA
| | - Peter Storz
- Department of Cancer Biology, Mayo Clinic, Griffin Room 306, 4500 San Pablo Road, Jacksonville, FL, 32224, USA.
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26
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Martin JC, Berton A, Ginies C, Bott R, Scheercousse P, Saddi A, Gripois D, Landrier JF, Dalemans D, Alessi MC, Delplanque B. Multilevel systems biology modeling characterized the atheroprotective efficiencies of modified dairy fats in a hamster model. Am J Physiol Heart Circ Physiol 2015; 309:H935-45. [PMID: 26071539 DOI: 10.1152/ajpheart.00032.2015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 06/15/2015] [Indexed: 12/20/2022]
Abstract
We assessed the atheroprotective efficiency of modified dairy fats in hyperlipidemic hamsters. A systems biology approach was implemented to reveal and quantify the dietary fat-related components of the disease. Three modified dairy fats (40% energy) were prepared from regular butter by mixing with a plant oil mixture, by removing cholesterol alone, or by removing cholesterol in combination with reducing saturated fatty acids. A plant oil mixture and a regular butter were used as control diets. The atherosclerosis severity (aortic cholesteryl-ester level) was higher in the regular butter-fed hamsters than in the other four groups (P < 0.05). Eighty-seven of the 1,666 variables measured from multiplatform analysis were found to be strongly associated with the disease. When aggregated into 10 biological clusters combined into a multivariate predictive equation, these 87 variables explained 81% of the disease variability. The biological cluster "regulation of lipid transport and metabolism" appeared central to atherogenic development relative to diets. The "vitamin E metabolism" cluster was the main driver of atheroprotection with the best performing transformed dairy fat. Under conditions that promote atherosclerosis, the impact of dairy fats on atherogenesis could be greatly ameliorated by technological modifications. Our modeling approach allowed for identifying and quantifying the contribution of complex factors to atherogenic development in each dietary setup.
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Affiliation(s)
- Jean-Charles Martin
- INRA UMR1260, Nutrition, Obésité et Risque Thrombotique, Marseille, France; Aix-Marseille Université, Faculté de Médecine, Marseille, France; and INSERM, UMR1062, Nutrition, Obésité et Risque Thrombotique, Marseille, France;
| | - Amélie Berton
- INRA UMR1260, Nutrition, Obésité et Risque Thrombotique, Marseille, France; Aix-Marseille Université, Faculté de Médecine, Marseille, France; and INSERM, UMR1062, Nutrition, Obésité et Risque Thrombotique, Marseille, France
| | - Christian Ginies
- INRA UMR1260, Nutrition, Obésité et Risque Thrombotique, Marseille, France; Aix-Marseille Université, Faculté de Médecine, Marseille, France; and INSERM, UMR1062, Nutrition, Obésité et Risque Thrombotique, Marseille, France
| | - Romain Bott
- INRA UMR1260, Nutrition, Obésité et Risque Thrombotique, Marseille, France; Aix-Marseille Université, Faculté de Médecine, Marseille, France; and INSERM, UMR1062, Nutrition, Obésité et Risque Thrombotique, Marseille, France
| | - Pierre Scheercousse
- INRA UMR1260, Nutrition, Obésité et Risque Thrombotique, Marseille, France; Aix-Marseille Université, Faculté de Médecine, Marseille, France; and INSERM, UMR1062, Nutrition, Obésité et Risque Thrombotique, Marseille, France
| | - Alessandra Saddi
- INRA UMR1260, Nutrition, Obésité et Risque Thrombotique, Marseille, France; Aix-Marseille Université, Faculté de Médecine, Marseille, France; and INSERM, UMR1062, Nutrition, Obésité et Risque Thrombotique, Marseille, France
| | - Daniel Gripois
- UMR 8195 Centre de Neurosciences Paris-Sud, Neuroendocrinologie Moléculaire de la Prise Alimentaire, Université Paris-Sud XI, Orsay, France; and
| | - Jean-François Landrier
- INRA UMR1260, Nutrition, Obésité et Risque Thrombotique, Marseille, France; Aix-Marseille Université, Faculté de Médecine, Marseille, France; and INSERM, UMR1062, Nutrition, Obésité et Risque Thrombotique, Marseille, France
| | | | - Marie-Christine Alessi
- INRA UMR1260, Nutrition, Obésité et Risque Thrombotique, Marseille, France; Aix-Marseille Université, Faculté de Médecine, Marseille, France; and INSERM, UMR1062, Nutrition, Obésité et Risque Thrombotique, Marseille, France
| | - Bernadette Delplanque
- UMR 8195 Centre de Neurosciences Paris-Sud, Neuroendocrinologie Moléculaire de la Prise Alimentaire, Université Paris-Sud XI, Orsay, France; and
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27
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Zhou X, Xue P, Yang M, Shi H, Lu D, Wang Z, Shi Q, Hu J, Xie S, Zhan W, Yu R. Protein kinase D2 promotes the proliferation of glioma cells by regulating Golgi phosphoprotein 3. Cancer Lett 2014; 355:121-9. [PMID: 25218347 DOI: 10.1016/j.canlet.2014.09.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Revised: 09/03/2014] [Accepted: 09/04/2014] [Indexed: 01/16/2023]
Abstract
Protein kinase D2 (PKD2) has been demonstrated to promote tumorigenesis in many types of cancers. However, how PKD2 regulates cancer cell growth is largely unknown. In this study, we found that over-expression of PKD2 promoted glioma cell growth but down-regulation of PKD2 inhibited it. Further investigation indicated that PKD2 down-regulation decreased the protein level of Golgi phosphoprotein 3(GOLPH3) as well as p-AKT level. On the contrary, over-expression of PKD2 increased the protein level of GOLPH3 and p-AKT. In addition, GOLPH3 exhibited similar effect on glioma cell growth to that of PKD2. Importantly, GOLPH3 down-regulation partially abolished glioma cell proliferation induced by PKD2 over-expression, while over-expression of GOLPH3 also partially rescued the inhibition effect of PKD2 down-regulation on glioma cell growth. Interestingly, the level of PKD2 and GOLPH3 significantly increased and was positively correlated in a cohort of glioma patients, as well as in patients from TCGA database. Taken together, these results reveal that PKD2 promotes glioma cell proliferation by regulating GOLPH3 and then AKT activation. Our findings indicate that both PKD2 and GOLPH3 play important roles in the progression of human gliomas and PKD2-GOLPH3-AKT signaling pathway might be a potential glioma therapeutic target.
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Affiliation(s)
- Xiuping Zhou
- Brain Hospital, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China; Insititute of Nervous System Diseases, Xuzhou Medical College, Xuzhou, Jiangsu, China.
| | - Pengfei Xue
- The Graduate School, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Minglin Yang
- The Graduate School, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Hengliang Shi
- Brain Hospital, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China; Insititute of Nervous System Diseases, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Dong Lu
- Brain Hospital, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China; Insititute of Nervous System Diseases, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Zhaohao Wang
- The Graduate School, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Qiong Shi
- Brain Hospital, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China; Insititute of Nervous System Diseases, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Jinxia Hu
- Brain Hospital, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China; Insititute of Nervous System Diseases, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Shao Xie
- Brain Hospital, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China; Insititute of Nervous System Diseases, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Wenjian Zhan
- Brain Hospital, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China; Insititute of Nervous System Diseases, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Rutong Yu
- Brain Hospital, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China; Insititute of Nervous System Diseases, Xuzhou Medical College, Xuzhou, Jiangsu, China.
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28
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Döppler H, Bastea LI, Borges S, Spratley SJ, Pearce SE, Storz P. Protein kinase d isoforms differentially modulate cofilin-driven directed cell migration. PLoS One 2014; 9:e98090. [PMID: 24840177 PMCID: PMC4026536 DOI: 10.1371/journal.pone.0098090] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 04/28/2014] [Indexed: 11/19/2022] Open
Abstract
Background Protein kinase D (PKD) enzymes regulate cofilin-driven actin reorganization and directed cell migration through both p21-activated kinase 4 (PAK4) and the phosphatase slingshot 1L (SSH1L). The relative contributions of different endogenous PKD isoforms to both signaling pathways have not been elucidated, sufficiently. Methodology/Principal Findings We here analyzed two cell lines (HeLa and MDA-MB-468) that express the subtypes protein kinase D2 (PKD2) and protein kinase D3 (PKD3). We show that under normal growth conditions both isoforms can form a complex, in which PKD3 is basally-active and PKD2 is inactive. Basal activity of PKD3 mediates PAK4 activity and downstream signaling, but does not significantly inhibit SSH1L. This signaling constellation was required for facilitating directed cell migration. Activation of PKD2 and further increase of PKD3 activity leads to additional phosphorylation and inhibition of endogenous SSH1L. Net effect is a dramatic increase in phospho-cofilin and a decrease in cell migration, since now both PAK4 and SSH1L are regulated by the active PKD2/PKD3 complex. Conclusions/Significance Our data suggest that PKD complexes provide an interface for both cofilin regulatory pathways. Dependent on the activity of involved PKD enzymes signaling can be balanced to guarantee a functional cofilin activity cycle and increase cell migration, or imbalanced to decrease cell migration. Our data also provide an explanation of how PKD isoforms mediate different effects on directed cell migration.
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Affiliation(s)
- Heike Döppler
- Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Ligia I. Bastea
- Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Sahra Borges
- Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Samantha J. Spratley
- Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Sarah E. Pearce
- Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Peter Storz
- Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida, United States of America
- * E-mail:
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29
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Peverill W, Powell LW, Skoien R. Evolving concepts in the pathogenesis of NASH: beyond steatosis and inflammation. Int J Mol Sci 2014; 15:8591-638. [PMID: 24830559 PMCID: PMC4057750 DOI: 10.3390/ijms15058591] [Citation(s) in RCA: 255] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 03/20/2014] [Accepted: 04/17/2014] [Indexed: 12/12/2022] Open
Abstract
Non-alcoholic steatohepatitis (NASH) is characterised by hepatic steatosis and inflammation and, in some patients, progressive fibrosis leading to cirrhosis. An understanding of the pathogenesis of NASH is still evolving but current evidence suggests multiple metabolic factors critically disrupt homeostasis and induce an inflammatory cascade and ensuing fibrosis. The mechanisms underlying these changes and the complex inter-cellular interactions that mediate fibrogenesis are yet to be fully elucidated. Lipotoxicity, in the setting of excess free fatty acids, obesity, and insulin resistance, appears to be the central driver of cellular injury via oxidative stress. Hepatocyte apoptosis and/or senescence contribute to activation of the inflammasome via a variety of intra- and inter-cellular signalling mechanisms leading to fibrosis. Current evidence suggests that periportal components, including the ductular reaction and expansion of the hepatic progenitor cell compartment, may be involved and that the Th17 response may mediate disease progression. This review aims to provide an overview of the pathogenesis of NASH and summarises the evidence pertaining to key mechanisms implicated in the transition from steatosis and inflammation to fibrosis. Currently there are limited treatments for NASH although an increasing understanding of its pathogenesis will likely improve the development and use of interventions in the future.
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Affiliation(s)
- William Peverill
- Department of Gastroenterology and Hepatology, Royal Brisbane and Women's Hospital, Brisbane 4029, Australia.
| | - Lawrie W Powell
- Department of Gastroenterology and Hepatology, Royal Brisbane and Women's Hospital, Brisbane 4029, Australia.
| | - Richard Skoien
- Department of Gastroenterology and Hepatology, Royal Brisbane and Women's Hospital, Brisbane 4029, Australia.
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30
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Ford JJ, Yeh LCC, Schmidgal EC, Thompson JF, Adamo ML, Lee JC. Protein kinase D1 is essential for bone acquisition during pubertal growth. Endocrinology 2013; 154:4182-91. [PMID: 23970783 PMCID: PMC5398594 DOI: 10.1210/en.2013-1376] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Bone formation and maintenance represents the summation of the balance of local and endocrine hormonal stimuli within a complex organ. Protein kinase D (PKD) is a member of the Ca(2+)/calmodulin-dependent kinase superfamily of serine/threonine kinases and has been described as the crossroads for the bone morphogenetic protein (BMP)-IGF-I signaling axis, which plays a major role in bone formation. The current study exploits the PKD1-deficient mouse model to examine the role of PKD in vivo in the skeleton. Dual-energy x-ray absorptiometry scan analysis of male and female pubescent mice demonstrated significantly decreased bone mineral density in the whole body and femoral bone compartments of PKD1 (+/-) mice, compared with their wild-type littermates. The body weight, nasal-anal length, and percentage body fat of the mice were not significantly different from their wild-type littermates. Cultured bone marrow stromal cells from PKD1 (+/-) mice demonstrated lower alkaline phosphatase activity in early differentiating osteoblasts and decreased mineralized nodule formation in mature osteoblasts. Quantitative RT-PCR analysis of osteoblast differentiation markers and osteoclast markers exhibited lower levels of expression in PKD1 (+/-) male mice than wild type. In female mice, however, only markers of osteoblast differentiation were reduced. PKD1 (+/-) mice also demonstrated a profound reduction in mRNA expression levels of BMP type II receptor and IGF-I receptor and in BMP-7 responsiveness in vitro. Together these data suggest that in mice, PKD1 action contributes to the regulation of osteoblastogenesis by altering gene expression with gender-specific effects on osteoclastogenesis, subsequently affecting skeletal matrix acquisition during puberty.
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Affiliation(s)
- Jeffery J Ford
- PhD, Department of Biochemistry, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229.
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Olayioye MA, Barisic S, Hausser A. Multi-level control of actin dynamics by protein kinase D. Cell Signal 2013; 25:1739-47. [PMID: 23688773 DOI: 10.1016/j.cellsig.2013.04.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 04/24/2013] [Accepted: 04/30/2013] [Indexed: 11/26/2022]
Abstract
Dynamic actin remodeling is fundamental to processes such as cell motility, vesicle trafficking, and cytokinesis. Protein kinase D (PKD) is a serine-threonine kinase known to be involved in diverse biological functions ranging from vesicle fission at the Golgi complex to regulation of cell motility and invasion. This review addresses the role of PKD in the organization of the actin cytoskeleton with a particular emphasis on the substrates associated with this function. We further highlight the multi-level control of actin dynamics by PKD and suggest that the tight spatio-temporal control of PKD activity is critical for the coordination of directed cell migration.
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Affiliation(s)
- Monilola A Olayioye
- Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, 70569 Stuttgart, Germany
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Lau WW, Chan AS, Poon LS, Zhu J, Wong YH. Gβγ-mediated activation of protein kinase D exhibits subunit specificity and requires Gβγ-responsive phospholipase Cβ isoforms. Cell Commun Signal 2013; 11:22. [PMID: 23561540 PMCID: PMC3637504 DOI: 10.1186/1478-811x-11-22] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 03/22/2013] [Indexed: 11/29/2022] Open
Abstract
Background Protein kinase D (PKD) constitutes a novel family of serine/threonine protein kinases implicated in fundamental biological activities including cell proliferation, survival, migration, and immune responses. Activation of PKD in these cellular activities has been linked to many extracellular signals acting through antigen receptor engagement, receptor tyrosine kinases, as well as G protein-coupled receptors. In the latter case, it is generally believed that the Gα subunits of the Gq family are highly effective in mediating PKD activation, whereas little is known with regard to the ability of Gβγ dimers and other Gα subunits to stimulate PKD. It has been suggested that the interaction between Gβγ and the PH domain of PKD, or the Gβγ-induced PLCβ/PKC activity is critical for the induction of PKD activation. However, the relative contribution of these two apparently independent events to Gβγ-mediated PKD activation has yet to be addressed. Results In this report, we demonstrate that among various members in the four G protein families, only the Gα subunits of the Gq family effectively activate all the three PKD isoforms (PKD1/2/3), while Gα subunits of other G protein families (Gs, Gi, and G12) are ineffective. Though the Gα subunits of Gi family are unable to stimulate PKD, receptors linked to Gi proteins are capable of triggering PKD activation in cell lines endogenously expressing (HeLa cells and Jurkat T-cells) or exogenously transfected with (HEK293 cells) Gβγ-sensitive PLCβ2/3 isoforms. This indicates that the Gi-mediated PKD activation is dependent on the released Gβγ dimers upon stimulation. Further investigation on individual Gβγ combinations (i.e. Gβ1 with Gγ1–13) revealed that, even if they can stimulate the PLCβ activity in a comparable manner, only those Gβ1γ dimers with γ2, γ3, γ4, γ5, γ7, and γ10 can serve as effective activators of PKD. We also demonstrated that Gi-mediated PKD activation is essential for the SDF-1α-induced chemotaxis on Jurkat T-cells. Conclusions Our current report illustrates that Gβγ dimers from the Gi proteins may activate PKD in a PLCβ2/3-dependent manner, and the specific identities of Gγ components within Gβγ dimers may determine this stimulatory action.
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Affiliation(s)
- Winnie Wi Lau
- Division of Life Science and the Biotechnology Research Institute, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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Mansky KC, Jensen ED, Davidova J, Yamamoto M, Gopalakrishnan R. Protein kinase D promotes in vitro osteoclast differentiation and fusion. J Biol Chem 2013; 288:9826-9834. [PMID: 23430742 DOI: 10.1074/jbc.m112.444133] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Although PKD is broadly expressed and involved in numerous cellular processes, its function in osteoclasts has not been previously reported. In this study, we found that PKD2 is the main PKD isoform expressed in osteoclastic cells. PKD phosphorylation, indicative of the activated state, increased after 2-3 days of treatment of bone marrow macrophages with M-CSF and RANKL, corresponding to the onset of preosteoclast fusion. RNAi against PKD2 and treatment with the PKD inhibitor CID755673 showed that PKD activity is dispensable for induction of bone marrow macrophages into tartrate-resistant acid phosphatase-positive preosteoclasts in culture but is required for the transition from mononucleated preosteoclasts to multinucleated osteoclasts. Loss of PKD activity reduced expression of DC-STAMP in RANKL-stimulated cultures. Overexpression of DC-STAMP was sufficient to rescue treatment with CID755673 and restore fusion into multinucleated osteoclasts. From these data, we conclude that PKD activity promotes differentiation of osteoclast progenitors through increased expression of DC-STAMP.
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Affiliation(s)
- Kim C Mansky
- Department of Developmental and Surgical Sciences, University of Minnesota, Minneapolis, Minnesota 55455
| | - Eric D Jensen
- Department of Diagnostic and Biological Sciences, University of Minnesota, Minneapolis, Minnesota 55455.
| | - Julia Davidova
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota 55455
| | - Masato Yamamoto
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota 55455
| | - Rajaram Gopalakrishnan
- Department of Diagnostic and Biological Sciences, University of Minnesota, Minneapolis, Minnesota 55455.
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Lysoglycerophospholipids in chronic inflammatory disorders: The PLA2/LPC and ATX/LPA axes. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:42-60. [DOI: 10.1016/j.bbalip.2012.07.019] [Citation(s) in RCA: 172] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 07/20/2012] [Accepted: 07/24/2012] [Indexed: 02/08/2023]
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Kilpinen L, Tigistu-Sahle F, Oja S, Greco D, Parmar A, Saavalainen P, Nikkilä J, Korhonen M, Lehenkari P, Käkelä R, Laitinen S. Aging bone marrow mesenchymal stromal cells have altered membrane glycerophospholipid composition and functionality. J Lipid Res 2012; 54:622-635. [PMID: 23271708 DOI: 10.1194/jlr.m030650] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Human mesenchymal stem/stromal cells (hMSC) are increasingly used in advanced cellular therapies. The clinical use of hMSCs demands sequential cell expansions. As it is well established that membrane glycerophospholipids (GPL) provide precursors for signaling lipids that modulate cellular functions, we studied the effect of the donor's age and cell doublings on the GPL profile of human bone marrow MSC (hBMSC). The hBMSCs, which were harvested from five young and five old adults, showed clear compositional changes during expansion seen at the level of lipid classes, lipid species, and acyl chains. The ratio of phosphatidylinositol to phosphatidylserine increased toward the late-passage samples. Furthermore, 20:4n-6-containing species of phosphatidylcholine and phosphatidylethanolamine accumulated while the species containing monounsaturated fatty acids (FA) decreased during passaging. Additionally, in the total FA pool of the cells, 20:4n-6 increased, which happened at the expense of n-3 polyunsaturated FAs, especially 22:6n-3. The GPL and FA correlated with the decreased immunosuppressive capacity of hBMSCs during expansion. Our observations were further supported by alterations in the gene expression levels of several enzymes involved in lipid metabolism and immunomodulation. The results show that extensive expansion of hBMSCs harmfully modulates membrane GPLs, affecting lipid signaling and eventually impairing functionality.
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Affiliation(s)
- Lotta Kilpinen
- Advanced Therapies and Product Development, Finnish Red Cross Blood Service, Helsinki, Finland
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Hao F, Wu DD, Xu X, Cui MZ. Histamine induces activation of protein kinase D that mediates tissue factor expression and activity in human aortic smooth muscle cells. Am J Physiol Heart Circ Physiol 2012; 303:H1344-52. [PMID: 23001835 DOI: 10.1152/ajpheart.00500.2011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Histamine, an inflammatory mediator, has been shown to influence the pathogenesis of vascular wall cells. However, the molecular basis of its influence is not well understood. Our data reveal that histamine markedly induces protein kinase D (PKD) activation in human aortic smooth muscle cells. PKD belongs to a family of serine/threonine protein kinases, and its function in vascular disease is largely unknown. Our data show that histamine-induced PKD phosphorylation is dependent on the activation of histamine receptor 1 and protein kinase C (PKC). To determine the role of PKD in the histamine pathway, we employed a small-interfering RNA approach to downregulate PKD expression and found that PKD1 and PKD2 are key mediators for expression of tissue factor (TF), which is the key initiator of blood coagulation and is important for thrombosis. Our results show that PKD2 predominantly mediates histamine-induced TF expression via the p38 mitogen-activated protein kinase (MAPK) pathway, whereas PKD1 mediates histamine-induced TF expression through a p38 MAPK-independent pathway. We demonstrate that histamine induces TF expression via the PKC-dependent PKD activation. Our data provide the first evidence that PKD is a new component in histamine signaling in live cells and that PKD has a novel function in the histamine signaling pathway leading to gene expression, as evidenced by TF expression. Importantly, our data reveal a regulatory link from histamine to PKD and TF, providing new insights into the mechanisms of coagulation and the development of atherothrombosis.
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Affiliation(s)
- Feng Hao
- Department of Biomedical & Diagnostic Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN 37996, USA
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A targeted library screen reveals a new inhibitor scaffold for protein kinase D. PLoS One 2012; 7:e44653. [PMID: 23028574 PMCID: PMC3445516 DOI: 10.1371/journal.pone.0044653] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 08/06/2012] [Indexed: 12/31/2022] Open
Abstract
Protein kinase D (PKD) has emerged as a potential therapeutic target in multiple pathological conditions, including cancer and heart diseases. Potent and selective small molecule inhibitors of PKD are valuable for dissecting PKD-mediated cellular signaling pathways and for therapeutic application. In this study, we evaluated a targeted library of 235 small organic kinase inhibitors for PKD1 inhibitory activity at a single concentration. Twenty-eight PKD inhibitory chemotypes were identified and six exhibited excellent PKD1 selectivity. Five of the six lead structures share a common scaffold, with compound 139 being the most potent and selective for PKD vs PKC and CAMK. Compound 139 was an ATP-competitive PKD1 inhibitor with a low double-digit nanomolar potency and was also cell-active. Kinase profiling analysis identified this class of small molecules as pan-PKD inhibitors, confirmed their selectivity again PKC and CAMK, and demonstrated an overall favorable selectivity profile that could be further enhanced through structural modification. Furthermore, using a PKD homology model based on similar protein kinase structures, docking modes for compound 139 were explored and compared to literature examples of PKD inhibition. Modeling of these compounds at the ATP-binding site of PKD was used to rationalize its high potency and provide the foundation for future further optimization. Accordingly, using biochemical screening of a small number of privileged scaffolds and computational modeling, we have identified a new core structure for highly potent PKD inhibition with promising selectivity against closely related kinases. These lead structures represent an excellent starting point for the further optimization and the design of selective and therapeutically effective small molecule inhibitors of PKD.
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Leonarduzzi G, Gamba P, Gargiulo S, Biasi F, Poli G. Inflammation-related gene expression by lipid oxidation-derived products in the progression of atherosclerosis. Free Radic Biol Med 2012; 52:19-34. [PMID: 22037514 DOI: 10.1016/j.freeradbiomed.2011.09.031] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 09/16/2011] [Accepted: 09/24/2011] [Indexed: 12/31/2022]
Abstract
Vascular areas of atherosclerotic development persist in a state of inflammation, and any further inflammatory stimulus in the subintimal area elicits a proatherogenic response; this alters the behavior of the artery wall cells and recruits further inflammatory cells. In association with the inflammatory response, oxidative events are also involved in the development of atherosclerotic plaques. It is now unanimously recognized that lipid oxidation-derived products are key players in the initiation and progression of atherosclerotic lesions. Oxidized lipids, derived from oxidatively modified low-density lipoproteins (LDLs), which accumulate in the intima, strongly modulate inflammation-related gene expression, through involvement of various signaling pathways. In addition, considerable evidence supports a proatherogenic role of a large group of potent bioactive lipids called eicosanoids, which derive from oxidation of arachidonic acid, a component of membrane phospholipids. Of note, LDL lipid oxidation products might regulate eicosanoid production, modulating the enzymatic degradation of arachidonic acid by cyclooxygenases and lipoxygenases; these enzymes might also directly contribute to LDL oxidation. This review provides a comprehensive overview of current knowledge on signal transduction pathways and inflammatory gene expression, modulated by lipid oxidation-derived products, in the progression of atherosclerosis.
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Hasegawa H, Lei J, Matsumoto T, Onishi S, Suemori K, Yasukawa M. Lysophosphatidylcholine enhances the suppressive function of human naturally occurring regulatory T cells through TGF-β production. Biochem Biophys Res Commun 2011; 415:526-31. [PMID: 22074829 DOI: 10.1016/j.bbrc.2011.10.119] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 10/26/2011] [Indexed: 11/30/2022]
Abstract
Naturally occurring CD4(+)CD25(+) regulatory T cells (nTregs) play a pivotal role in the maintenance of self-tolerance and immune homeostasis. To gain insight into the mechanism of action of nTregs in pathological and physiological immune responses, it is important to analyze bioactive molecules that modulate the maintenance and function of nTregs. From a library of bioactive lipids, we obtained lysophosphatidylcholine (LPC) as a molecule that enhanced the Foxp3 expression and suppressive function of human nTregs significantly in comparison with those of DMSO-treated nTregs (control). The expression levels of TGF-β1 mRNA and protein in LPC-treated nTregs were significantly higher than those in control nTregs. After treatment with anti-TGF-β1 antibody, the increases in Foxp3 expression and the suppressive properties of LPC-treated nTregs returned to the levels observed in control nTregs. These findings indicate that LPC enhances Foxp3 expression and the suppressive function of nTregs through TGF-β1 produced by nTregs themselves. Experimental knockdown of G2A and GPR4 showed that this LPC-induced TGF-β1 expression in nTregs was due to G2A signaling, and did not involve GPR4. Moreover, JNK was a major contributor to LPC-induced TGF-β1 expression in nTregs, although LPC activated MAPKs including ERK1/2, p38 MAPK, and JNK via G2A. LPC is a bioactive lysolipid highly abundant in the circulation. Therefore, LPC may contribute to the maintenance and function of human nTregs in vivo.
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Affiliation(s)
- Hitoshi Hasegawa
- Department of Bioregulatory Medicine, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295, Japan.
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Just S, Berger IM, Meder B, Backs J, Keller A, Marquart S, Frese K, Patzel E, Rauch GJ, Katus HA, Rottbauer W. Protein kinase D2 controls cardiac valve formation in zebrafish by regulating histone deacetylase 5 activity. Circulation 2011; 124:324-34. [PMID: 21730303 DOI: 10.1161/circulationaha.110.003301] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The molecular mechanisms that guide heart valve formation are not well understood. However, elucidation of the genetic basis of congenital heart disease is one of the prerequisites for the development of tissue-engineered heart valves. METHODS AND RESULTS We isolated here a mutation in zebrafish, bungee (bng(jh177)), which selectively perturbs valve formation in the embryonic heart by abrogating endocardial Notch signaling in cardiac cushions. We found by positional cloning that the bng phenotype is caused by a missense mutation (Y849N) in zebrafish protein kinase D2 (pkd2). The bng mutation selectively impairs PKD2 kinase activity and hence Histone deacetylase 5 phosphorylation, nuclear export, and inactivation. As a result, the expression of Histone deacetylase 5 target genes Krüppel-like factor 2a and 4a, transcription factors known to be pivotal for heart valve formation and to act upstream of Notch signaling, is severely downregulated in bungee (bng) mutant embryos. Accordingly, the expression of Notch target genes, such as Hey1, Hey2, and HeyL, is severely decreased in bng mutant embryos. Remarkably, downregulation of Histone deacetylase 5 activity in homozygous bng mutant embryos can rescue the mutant phenotype and reconstitutes notch1b expression in atrioventricular endocardial cells. CONCLUSIONS We demonstrate for the first time that proper heart valve formation critically depends on Protein kinase D2-Histone deacetylase 5-Krüppel-like factor signaling.
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Affiliation(s)
- Steffen Just
- Department of Medicine II, University of Ulm, Albert-Einstein-Allee 23, 89081 Ulm, Germany
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Protein kinase C mediates platelet secretion and thrombus formation through protein kinase D2. Blood 2011; 118:416-24. [PMID: 21527521 DOI: 10.1182/blood-2010-10-312199] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Platelets are highly specialized blood cells critically involved in hemostasis and thrombosis. Members of the protein kinase C (PKC) family have established roles in regulating platelet function and thrombosis, but the molecular mechanisms are not clearly understood. In particular, the conventional PKC isoform, PKCα, is a major regulator of platelet granule secretion, but the molecular pathway from PKCα to secretion is not defined. Protein kinase D (PKD) is a family of 3 kinases activated by PKC, which may represent a step in the PKC signaling pathway to secretion. In the present study, we show that PKD2 is the sole PKD member regulated downstream of PKC in platelets, and that the conventional, but not novel, PKC isoforms provide the upstream signal. Platelets from a gene knock-in mouse in which 2 key phosphorylation sites in PKD2 have been mutated (Ser707Ala/Ser711Ala) show a significant reduction in agonist-induced dense granule secretion, but not in α-granule secretion. This deficiency in dense granule release was responsible for a reduced platelet aggregation and a marked reduction in thrombus formation. Our results show that in the molecular pathway to secretion, PKD2 is a key component of the PKC-mediated pathway to platelet activation and thrombus formation through its selective regulation of dense granule secretion.
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Abstract
Mammalian PKD (protein kinase D) isoforms have been implicated in the regulation of diverse biological processes in response to diacylglycerol and PKC (protein kinase C) signalling. To compare the functions of PKD1 and PKD2 in vivo, we generated mice deficient in either PKD1 or PKD2 enzymatic activity, via homozygous expression of PKD1S744A/S748A or PKD2S707A/S711A ‘knockin’ alleles. We also examined PKD2-deficient mice generated using ‘gene-trap’ technology. We demonstrate that, unlike PKD1, PKD2 catalytic activity is dispensable for normal embryogenesis. We also show that PKD2 is the major PKD isoform expressed in lymphoid tissues, but that PKD2 catalytic activity is not essential for the development of mature peripheral T- and B-lymphocytes. PKD2 catalytic activity is, however, required for efficient antigen receptor-induced cytokine production in T-lymphocytes and for optimal T-cell-dependent antibody responses in vivo. Our results reveal a key in vivo role for PKD2 in regulating the function of mature peripheral lymphocytes during adaptive immune responses. They also confirm the functional importance of PKC-mediated serine phosphorylation of the PKD catalytic domain for PKD activation and downstream signalling and reveal that different PKD family members have unique and non-redundant roles in vivo.
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Abstract
PURPOSE OF REVIEW Oxidized phospholipids (OxPLs) are abundantly found at sites of inflammation and are considered to play an active role in the modulation of the immune response. Whereas most studies attributed a proinflammatory role to OxPLs, recent studies demonstrate that some products of phospholipid oxidation may in fact exhibit anti-inflammatory properties. This study summarizes the proinflammatory and anti-inflammatory properties of OxPLs and sheds light on the therapeutic potential of OxPL derivatives or analogs for treatment of chronic inflammatory disorders. RECENT FINDINGS OxPLs may inhibit activation of several Toll-like receptors and can epigenetically reduce the capacity of dendritic cells to function as mature, fully functional immunostimulatory cells. These data demonstrate that OxPLs can induce anti-inflammatory effects. Moreover, VB-201, an orally available synthetic phospholipid analog of the Lecinoxoid family, was found to attenuate inflammation in various preclinical animal models and is currently employed in a phase II clinical trial in psoriasis. SUMMARY Chemical or biological modifications of phospholipids yield various products, some of which may exhibit anti-inflammatory properties. Identification of such species and generation of more stable/potent anti-inflammatory OxPL variants may represent a novel approach for the treatment of immune-mediated diseases such as psoriasis, atherosclerosis, multiple sclerosis and rheumatoid arthritis.
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Suckling K. Phospholipase A2s: Developing drug targets for atherosclerosis. Atherosclerosis 2010; 212:357-66. [DOI: 10.1016/j.atherosclerosis.2010.03.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 03/08/2010] [Accepted: 03/08/2010] [Indexed: 12/24/2022]
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Neuschwander-Tetri BA. Hepatic lipotoxicity and the pathogenesis of nonalcoholic steatohepatitis: the central role of nontriglyceride fatty acid metabolites. Hepatology 2010; 52:774-88. [PMID: 20683968 DOI: 10.1002/hep.23719] [Citation(s) in RCA: 775] [Impact Index Per Article: 55.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A significant body of evidence now forces us to rethink the causes of NASH. Once thought to be a disease caused by triglyceride accumulation in hepatocytes with subsequent oxidant stress and lipid peroxidation causing inflammation and fibrosis, new data from animal studies and a limited number of human studies now provide convincing evidence that triglyceride accumulation does not cause insulin resistance or cellular injury in the liver. The lipotoxic liver injury hypothesis for the pathogenesis of NASH suggests that we need to focus our therapeutic efforts on reducing the burden of fatty acids going to the liver or being synthesized in the liver. This can be accomplished by improving insulin sensitivity at the level of adipose tissue to prevent inappropriate peripheral lipolysis and by preventing unnecessary de novo lipogenesis in the liver. Excess carbohydrates are the major substrates for de novo lipogenesis, and thus, reducing carbohydrate consumption through dietary changes and increasing muscle glucose uptake through exercise remain important cornerstones of treatment and prevention of lipotoxic liver injury, a disease hitherto called NASH.
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Aviram M. Atherosclerosis: cell biology and lipoproteins--oxidative stress and paraoxonases regulate atherogenesis. Curr Opin Lipidol 2010; 21:163-4. [PMID: 20616631 DOI: 10.1097/mol.0b013e3283376936] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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