1
|
Fan Y, Xu F, Wang R, He J. Lysine 222 in PPAR γ1 functions as the key site of MuRF2-mediated ubiquitination modification. Sci Rep 2023; 13:1999. [PMID: 36737649 PMCID: PMC9898238 DOI: 10.1038/s41598-023-28905-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 01/27/2023] [Indexed: 02/05/2023] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPAR γ) plays key roles in the development, physiology, reproduction, and homeostasis of organisms. Its expression and activity are regulated by various posttranslational modifications. We previously reported that E3 ubiquitin ligase muscle ring finger protein 2 (MuRF2) inhibits cardiac PPAR γ1 protein level and activity, eventually protects heart from diabetic cardiomyopathy; furthermore, by GST-pulldown assay, we found that MuRF2 modifies PPAR γ1 via poly-ubiquitination and accelerates PPAR γ1 proteasomal degradation. However, the key ubiquitination site on PPAR γ that MuRF2 targets for remains unclear. In the present study, we demonstrate that lysine site 222 is the receptor of MuRF2-mediated PPAR γ1 ubiquitination modification, using prediction of computational models, immunoprecipitation, ubiquitination assays, cycloheximide chasing assay and RT-qPCR. Our findings elucidated the underlying details of MuRF2 prevents heart from diabetic cardiomyopathy through the PPAR γ1 regulatory pathway.
Collapse
Affiliation(s)
- Yucheng Fan
- Department of Pathology, The First People's Hospital of Shizuishan, Affiliated to Ningxia Medical University, Shizuishan, China
| | - Fangjing Xu
- School of Clinical Medicine, Ningxia Medical University, Yinchuan, China
| | - Rui Wang
- School of Basic Medical Sciences , Ningxia Medical University, Yinchuan, China
| | - Jun He
- Department of Cardiovascular Internal Medicine, General Hospital of Ningxia Medical University, Yinchuan, China.
| |
Collapse
|
2
|
The Role of Transcription Factor PPAR-γ in the Pathogenesis of Psoriasis, Skin Cells, and Immune Cells. Int J Mol Sci 2022; 23:ijms23179708. [PMID: 36077103 PMCID: PMC9456565 DOI: 10.3390/ijms23179708] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 11/22/2022] Open
Abstract
The peroxisome proliferator-activated receptor PPAR-γ is one of three PPAR nuclear receptors that act as ligand-activated transcription factors. In immune cells, the skin, and other organs, PPAR-γ regulates lipid, glucose, and amino acid metabolism. The receptor translates nutritional, pharmacological, and metabolic stimuli into the changes in gene expression. The activation of PPAR-γ promotes cell differentiation, reduces the proliferation rate, and modulates the immune response. In the skin, PPARs also contribute to the functioning of the skin barrier. Since we know that the route from identification to the registration of drugs is long and expensive, PPAR-γ agonists already approved for other diseases may also represent a high interest for psoriasis. In this review, we discuss the role of PPAR-γ in the activation, differentiation, and proliferation of skin and immune cells affected by psoriasis and in contributing to the pathogenesis of the disease. We also evaluate whether the agonists of PPAR-γ may become one of the therapeutic options to suppress the inflammatory response in lesional psoriatic skin and decrease the influence of comorbidities associated with psoriasis.
Collapse
|
3
|
Muzio G, Barrera G, Pizzimenti S. Peroxisome Proliferator-Activated Receptors (PPARs) and Oxidative Stress in Physiological Conditions and in Cancer. Antioxidants (Basel) 2021; 10:antiox10111734. [PMID: 34829605 PMCID: PMC8614822 DOI: 10.3390/antiox10111734] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 12/18/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor superfamily. Originally described as “orphan nuclear receptors”, they can bind both natural and synthetic ligands acting as agonists or antagonists. In humans three subtypes, PPARα, β/δ, γ, are encoded by different genes, show tissue-specific expression patterns, and contribute to the regulation of lipid and carbohydrate metabolisms, of different cell functions, including proliferation, death, differentiation, and of processes, as inflammation, angiogenesis, immune response. The PPAR ability in increasing the expression of various antioxidant genes and decreasing the synthesis of pro-inflammatory mediators, makes them be considered among the most important regulators of the cellular response to oxidative stress conditions. Based on the multiplicity of physiological effects, PPAR involvement in cancer development and progression has attracted great scientific interest with the aim to describe changes occurring in their expression in cancer cells, and to investigate the correlation with some characteristics of cancer phenotype, including increased proliferation, decreased susceptibility to apoptosis, malignancy degree and onset of resistance to anticancer drugs. This review focuses on mechanisms underlying the antioxidant and anti-inflammatory properties of PPARs in physiological conditions, and on the reported beneficial effects of PPAR activation in cancer.
Collapse
|
4
|
Bta-miR-2400 Targets SUMO1 to Affect Yak Preadipocytes Proliferation and Differentiation. BIOLOGY 2021; 10:biology10100949. [PMID: 34681048 PMCID: PMC8533534 DOI: 10.3390/biology10100949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 11/17/2022]
Abstract
Yak adipose tissue may have evolved a unique energy metabolism manner to accommodate the organism's seasonal growth rhythms. MiRNAs regulate multiple biological processes including systemic metabolism and energy homeostasis through post-transcriptional regulations. Rare reports have shown that miRNAs regulate lipid metabolism in domestic yaks. Therefore, we investigated the regulatory mechanisms of bta-miR-2400 in modulating yak preadipocytes proliferation and differentiation. We found that bta-miR-2400 was highly expressed in adipose tissue. Overexpression of bta-miR-2400 in yak preadipocytes significantly enhanced cell proliferation, increased the number of EdU fluorescence-stained cells, and promoted the expression of proliferation marker genes (CDK2, CDK4 and PCNA). Besides, overexpression of bta-miR-2400 repressed the expression of adipogenesis-related marker genes, and the content of cellular triglyceride was substantially reduced. Conversely, inhibition of bta-miR-2400 showed opposite effects compared to those of bta-miR-2400 overexpression in yak preadipocytes. Further, luciferase reporter assays revealed that SUMO1 is a target gene of bta-miR-2400, with bta-miR-2400 being able to down-regulate SUMO1 mRNA and protein expression. In conclusion, bta-miR-2400 regulates lipid metabolism and energy homeostasis in yak preadipocytes by directly targeting SUMO1 to promote cell proliferation and inhibit differentiation.
Collapse
|
5
|
Tahri-Joutey M, Andreoletti P, Surapureddi S, Nasser B, Cherkaoui-Malki M, Latruffe N. Mechanisms Mediating the Regulation of Peroxisomal Fatty Acid Beta-Oxidation by PPARα. Int J Mol Sci 2021; 22:ijms22168969. [PMID: 34445672 PMCID: PMC8396561 DOI: 10.3390/ijms22168969] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/14/2021] [Accepted: 08/15/2021] [Indexed: 12/12/2022] Open
Abstract
In mammalian cells, two cellular organelles, mitochondria and peroxisomes, share the ability to degrade fatty acid chains. Although each organelle harbors its own fatty acid β-oxidation pathway, a distinct mitochondrial system feeds the oxidative phosphorylation pathway for ATP synthesis. At the same time, the peroxisomal β-oxidation pathway participates in cellular thermogenesis. A scientific milestone in 1965 helped discover the hepatomegaly effect in rat liver by clofibrate, subsequently identified as a peroxisome proliferator in rodents and an activator of the peroxisomal fatty acid β-oxidation pathway. These peroxisome proliferators were later identified as activating ligands of Peroxisome Proliferator-Activated Receptor α (PPARα), cloned in 1990. The ligand-activated heterodimer PPARα/RXRα recognizes a DNA sequence, called PPRE (Peroxisome Proliferator Response Element), corresponding to two half-consensus hexanucleotide motifs, AGGTCA, separated by one nucleotide. Accordingly, the assembled complex containing PPRE/PPARα/RXRα/ligands/Coregulators controls the expression of the genes involved in liver peroxisomal fatty acid β-oxidation. This review mobilizes a considerable number of findings that discuss miscellaneous axes, covering the detailed expression pattern of PPARα in species and tissues, the lessons from several PPARα KO mouse models and the modulation of PPARα function by dietary micronutrients.
Collapse
Affiliation(s)
- Mounia Tahri-Joutey
- Bio-PeroxIL Laboratory, University of Bourgogne Franche-Comté, 21000 Dijon, France; (M.T.-J.); (P.A.); (M.C.-M.)
- Laboratory of Biochemistry, Neurosciences, Natural Resources and Environment, Faculty of Sciences & Techniques, University Hassan I, BP 577, 26000 Settat, Morocco;
| | - Pierre Andreoletti
- Bio-PeroxIL Laboratory, University of Bourgogne Franche-Comté, 21000 Dijon, France; (M.T.-J.); (P.A.); (M.C.-M.)
| | - Sailesh Surapureddi
- Office of Pollution Prevention and Toxics, United States Environmental Protection Agency, Washington, DC 20460, USA;
| | - Boubker Nasser
- Laboratory of Biochemistry, Neurosciences, Natural Resources and Environment, Faculty of Sciences & Techniques, University Hassan I, BP 577, 26000 Settat, Morocco;
| | - Mustapha Cherkaoui-Malki
- Bio-PeroxIL Laboratory, University of Bourgogne Franche-Comté, 21000 Dijon, France; (M.T.-J.); (P.A.); (M.C.-M.)
| | - Norbert Latruffe
- Bio-PeroxIL Laboratory, University of Bourgogne Franche-Comté, 21000 Dijon, France; (M.T.-J.); (P.A.); (M.C.-M.)
- Correspondence:
| |
Collapse
|
6
|
Zhang Y, Chen Y, Sun H, Zhang W, Zhang L, Li H, Huang X, Yang J, Ye Z. SENP3-Mediated PPARγ2 DeSUMOylation in BM-MSCs Potentiates Glucocorticoid-Induced Osteoporosis by Promoting Adipogenesis and Weakening Osteogenesis. Front Cell Dev Biol 2021; 9:693079. [PMID: 34249943 PMCID: PMC8266396 DOI: 10.3389/fcell.2021.693079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 05/26/2021] [Indexed: 12/23/2022] Open
Abstract
Glucocorticoid-induced osteoporosis (GIOP) is the most common secondary osteoporosis and reduced bone formation was the main pathological change in GIOP. Our previous studies have shown that there was an imbalance between adipogenic and osteogenic differentiation in GIOP BM-MSCs and peroxisome proliferator-activated receptor γ2 (PPARγ2) played a vital role in this disorders. Here, we reported that there was an increase in ROS level and SENP3 expression in Dex-induced osteoporotic BM-MSCs, and enhanced adipogenesis and weakened osteogenesis in osteoporotic BM-MSCs might be caused by upregulated SENP3. Then we found that SENP3 de-SUMOylated PPARγ2 on K107 site to potentiate adipogenesis and weaken osteogenesis. These results may provide new strategy and target in the clinical diagnosis and treatment of GIOP.
Collapse
Affiliation(s)
- Yongxing Zhang
- Musculoskeletal Tumor Center, Department of Orthopedics, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.,Institute of Orthopedic Research, Zhejiang University, Hangzhou, China.,Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Department of Biochemistry and Molecular Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yang Chen
- Department of Ultrasound, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Hangxiang Sun
- Musculoskeletal Tumor Center, Department of Orthopedics, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.,Institute of Orthopedic Research, Zhejiang University, Hangzhou, China
| | - Wenkan Zhang
- Musculoskeletal Tumor Center, Department of Orthopedics, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.,Institute of Orthopedic Research, Zhejiang University, Hangzhou, China
| | - Lingling Zhang
- Musculoskeletal Tumor Center, Department of Orthopedics, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.,Institute of Orthopedic Research, Zhejiang University, Hangzhou, China
| | - Hengyuan Li
- Musculoskeletal Tumor Center, Department of Orthopedics, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.,Institute of Orthopedic Research, Zhejiang University, Hangzhou, China
| | - Xin Huang
- Musculoskeletal Tumor Center, Department of Orthopedics, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.,Institute of Orthopedic Research, Zhejiang University, Hangzhou, China
| | - Jie Yang
- Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Department of Biochemistry and Molecular Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhaoming Ye
- Musculoskeletal Tumor Center, Department of Orthopedics, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.,Institute of Orthopedic Research, Zhejiang University, Hangzhou, China
| |
Collapse
|
7
|
Cataldi S, Costa V, Ciccodicola A, Aprile M. PPARγ and Diabetes: Beyond the Genome and Towards Personalized Medicine. Curr Diab Rep 2021; 21:18. [PMID: 33866450 DOI: 10.1007/s11892-021-01385-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/25/2021] [Indexed: 12/13/2022]
Abstract
PURPOSE OF REVIEW Full and partial synthetic agonists targeting the transcription factor PPARγ are contained in FDA-approved insulin-sensitizing drugs and used for the treatment of metabolic syndrome-related dysfunctions. Here, we discuss the association between PPARG genetic variants and drug efficacy, as well as the role of alternative splicing and post-translational modifications as contributors to the complexity of PPARγ signaling and to the effects of synthetic PPARγ ligands. RECENT FINDINGS PPARγ regulates the transcription of several target genes governing adipocyte differentiation and glucose and lipid metabolism, as well as insulin sensitivity and inflammatory pathways. These pleiotropic functions confer great relevance to PPARγ in physiological regulation of whole-body metabolism, as well as in the etiology of metabolic disorders. Accordingly, PPARG gene mutations, nucleotide variations, and post-translational modifications have been associated with adipose tissue disorders and the related risk of insulin resistance and type 2 diabetes (T2D). Moreover, PPARγ alternative splicing isoforms-generating dominant-negative isoforms mainly expressed in human adipose tissue-have been related to impaired PPARγ activity and adipose tissue dysfunctions. Thus, multiple regulatory levels that contribute to PPARγ signaling complexity may account for the beneficial as well as adverse effects of PPARγ agonists. Further targeted analyses, taking into account all these aspects, are needed for better deciphering the role of PPARγ in human pathophysiology, especially in insulin resistance and T2D. The therapeutic potential of full and partial PPARγ synthetic agonists underlines the clinical significance of this nuclear receptor. PPARG mutations, polymorphisms, alternative splicing isoforms, and post-translational modifications may contribute to the pathogenesis of metabolic disorders, also influencing the responsiveness of pharmacological therapy. Therefore, in the context of the current evidence-based trend to personalized diabetes management, we highlight the need to decipher the intricate regulation of PPARγ signaling to pave the way to tailored therapies in patients with insulin resistance and T2D.
Collapse
Affiliation(s)
- Simona Cataldi
- Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR, Via P. Castellino 111, 80131, Naples, Italy
| | - Valerio Costa
- Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR, Via P. Castellino 111, 80131, Naples, Italy
| | - Alfredo Ciccodicola
- Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR, Via P. Castellino 111, 80131, Naples, Italy.
- Department of Science and Technology, University of Naples "Parthenope", 80131, Naples, Italy.
| | - Marianna Aprile
- Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR, Via P. Castellino 111, 80131, Naples, Italy
| |
Collapse
|
8
|
Mukohda M. [Role of PPARγ, a transcription factor in cardiovascular disease]. Nihon Yakurigaku Zasshi 2019; 154:56-60. [PMID: 31406043 DOI: 10.1254/fpj.154.56] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Peroxisome proliferator-activated receptor γ (PPARγ) is a ligand activated transcription factor known to regulate fatty acid metabolism. Thiazolidinediones (TZDs), PPARγ synthetic agonists, currently used to treat patients with type 2 diabetes, have been shown to lower the blood pressure and protect against vascular diseases such as atherosclerosis. In line with these findings, it has been reported that individuals with loss-of-function mutations of PPARγ developed sever early-onset hypertension in addition to metabolic abnormalities. Accumulating evidences suggest PPARγ in the vasculature has protective effects on cardiovascular disease despite unclear mechanism. Because of ubiquitous expression of PPARγ, TZDs are well-known to be associated with serious side effects such as weight gain, fluid retention, and bone fractures. Thus identification of mechanisms on tissue-specific PPARγ activity may lead to the development of targeted treatment which is characterized by no deleterious effects. This review discusses role of PPARγ in cardiovascular disease.
Collapse
Affiliation(s)
- Masashi Mukohda
- Laboratory of Veterinary Pharmacology, Faculty of Veterinary Medicine, Okayama University of Science
| |
Collapse
|
9
|
Aydoğan BI, Erarslan E, Ünlütürk U, Güllü S. Effects of telmisartan and losartan treatments on bone turnover markers in patients with newly diagnosed stage I hypertension. J Renin Angiotensin Aldosterone Syst 2019; 20:1470320319862741. [PMID: 31328615 PMCID: PMC6647217 DOI: 10.1177/1470320319862741] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
INTRODUCTION Telmisartan is an angiotensin-II receptor type-1 blocker and a partial agonist for peroxisome proliferator-activated receptor-γ. The aim of this study was to determine the potential effects of telmisartan on bone metabolism and turnover markers. METHODS Forty-two patients with newly diagnosed stage I hypertension who were prescribed telmisartan 80 mg/day or losartan 100 mg/day were included. Serum levels of calcium, phosphorus, 25-hydroxy vitamin D, bone-specific alkaline phosphatase, osteocalcin, interleukin 6 and 24-hour urinary N-terminal telopeptide were measured at the beginning and after 12 weeks of treatment. RESULTS When treatment arms were evaluated together, significantly increased 25-hydroxy vitamin D levels (p=0.01), and decreased parathormone (PTH) (p<0.001), bone-specific alkaline phosphatase (p=0.01), osteocalcin (p=0.045), urinary N-terminal telopeptide (p<0.001) and interleukin 6 levels (p=0.006) were observed. After eliminating the 25-hydroxy vitamin D effect, significant changes were not observed at any of the parameters. None of the levels of parameters were different between groups. CONCLUSIONS Neither telmisartan, despite its partial peroxisome proliferator-activated receptor-γ agonistic effect, nor losartan treatment had significant effects on bone turnover markers in newly diagnosed stage I hypertensive patients.
Collapse
Affiliation(s)
- Berna I Aydoğan
- 1 Department of Endocrinology and Metabolism, Ankara University School of Medicine, Turkey
| | - Emrah Erarslan
- 1 Department of Endocrinology and Metabolism, Ankara University School of Medicine, Turkey
| | - Uğur Ünlütürk
- 1 Department of Endocrinology and Metabolism, Ankara University School of Medicine, Turkey.,2 Department of Endocrinology and Metabolism, Hacettepe University School of Medicine, Turkey
| | - Sevim Güllü
- 1 Department of Endocrinology and Metabolism, Ankara University School of Medicine, Turkey
| |
Collapse
|
10
|
Broekema M, Savage D, Monajemi H, Kalkhoven E. Gene-gene and gene-environment interactions in lipodystrophy: Lessons learned from natural PPARγ mutants. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:715-732. [DOI: 10.1016/j.bbalip.2019.02.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 01/13/2019] [Accepted: 02/02/2019] [Indexed: 12/13/2022]
|
11
|
Grytting VS, Olderbø BP, Holme JA, Samuelsen JT, Solhaug A, Becher R, Bølling AK. Di-n-butyl phthalate modifies PMA-induced macrophage differentiation of THP-1 monocytes via PPARγ. Toxicol In Vitro 2019; 54:168-177. [DOI: 10.1016/j.tiv.2018.09.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 08/14/2018] [Accepted: 09/10/2018] [Indexed: 12/16/2022]
|
12
|
Xie B, Liu X, Yang J, Cheng J, Gu J, Xue S. PIAS1 protects against myocardial ischemia-reperfusion injury by stimulating PPARγ SUMOylation. BMC Cell Biol 2018; 19:24. [PMID: 30419807 PMCID: PMC6233564 DOI: 10.1186/s12860-018-0176-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 10/25/2018] [Indexed: 01/07/2023] Open
Abstract
Background Myocardial ischemia-reperfusion injury (IRI) has become one of the most serious complications after reperfusion therapy in patients with acute myocardial infarction. Small ubiquitin-like modification (SUMOylation) is a reversible process, including SUMO E1-, E2-, and E3-mediated SUMOylation and SUMO-specific protease-mediated deSUMOylation, with the latter having been shown to play a vital role in myocardial IRI previously. However, little is known about the function and regulation of SUMO E3 ligases in myocardial IRI. Results In this study, we found dramatically decreased expression of PIAS1 after ischemia/reperfusion (I/R) in mouse myocardium and H9C2 cells. PIAS1 deficiency aggravated apoptosis and inflammation of cardiomyocytes via activating the NF-κB pathway after I/R. Mechanistically, we identified PIAS1 as a specific E3 ligase for PPARγ SUMOylation. Moreover, H9C2 cells treated with hypoxia/reoxygenation (H/R) displayed reduced PPARγ SUMOylation as a result of down-regulated PIAS1, and act an anti-apoptotic and anti-inflammatory function through repressing NF-κB activity. Finally, overexpression of PIAS1 in H9C2 cells could remarkably ameliorate I/R injury. Conclusions Collectively, our findings demonstrate the crucial role of PIAS1-mediated PPARγ SUMOylation in protecting against myocardial IRI. Electronic supplementary material The online version of this article (10.1186/s12860-018-0176-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Bo Xie
- Department of Cardiovascular Surgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, 160 Pujian Road, Shanghai, 200127, China
| | - Xinyu Liu
- Department of General Surgery, Qingpu Branch of Zhongshan Hospital, Fudan University, 201700, 1158 East Gongyuan Road, Shanghai, China
| | - Jie Yang
- Core Facility of Basic Medical Sciences, Shanghai Jiao Tong University School of Medicine, 200025, 280 South Chongqing Road, Shanghai, China
| | - Jinke Cheng
- Department of Biochemistry and Molecular Cell Biology, Key Laboratory for Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, 200025, 280 South Chongqing Road, Shanghai, China
| | - Jianmin Gu
- Department of Cardiovascular Surgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, 160 Pujian Road, Shanghai, 200127, China.
| | - Song Xue
- Department of Cardiovascular Surgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, 160 Pujian Road, Shanghai, 200127, China.
| |
Collapse
|
13
|
Functional Regulation of PPARs through Post-Translational Modifications. Int J Mol Sci 2018; 19:ijms19061738. [PMID: 29895749 PMCID: PMC6032173 DOI: 10.3390/ijms19061738] [Citation(s) in RCA: 150] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/05/2018] [Accepted: 06/07/2018] [Indexed: 12/11/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptor superfamily and they are essential regulators of cell differentiation, tissue development, and energy metabolism. Given their central roles in sensing the cellular metabolic state and controlling metabolic homeostasis, PPARs became important targets of drug development for the management of metabolic disorders. The function of PPARs is mainly regulated through ligand binding, which induces structural changes, further affecting the interactions with co-activators or co-repressors to stimulate or inhibit their functions. In addition, PPAR functions are also regulated by various Post-translational modifications (PTMs). These PTMs include phosphorylation, SUMOylation, ubiquitination, acetylation, and O-GlcNAcylation, which are found at numerous modification sites. The addition of these PTMs has a wide spectrum of consequences on protein stability, transactivation function, and co-factor interaction. Moreover, certain PTMs in PPAR proteins have been associated with the status of metabolic diseases. In this review, we summarize the PTMs found on the three PPAR isoforms PPARα, PPARβ/δ, and PPARγ, and their corresponding modifying enzymes. We also discuss the functional roles of these PTMs in regulating metabolic homeostasis and provide a perspective for future research in this intriguing field.
Collapse
|
14
|
Abstract
Protein modification with the small ubiquitin-related modifier (SUMO) can affect protein function, enzyme activity, protein-protein interactions, protein stability, protein targeting and cellular localization. SUMO influences the function and regulation of metabolic enzymes within pathways, and in some cases targets entire metabolic pathways by affecting the activity of transcription factors or by facilitating the translocation of entire metabolic pathways to subcellular compartments. SUMO modification is also a key component of nutrient- and metabolic-sensing mechanisms that regulate cellular metabolism. In addition to its established roles in maintaining metabolic homeostasis, there is increasing evidence that SUMO is a key factor in facilitating cellular stress responses through the regulation and/or adaptation of the most fundamental metabolic processes, including energy and nucleotide metabolism. This review focuses on the role of SUMO in cellular metabolism and metabolic disease.
Collapse
|
15
|
Wang S, Goodspeed L, Turk KE, Houston B, den Hartigh LJ. Rosiglitazone Improves Insulin Resistance Mediated by 10,12 Conjugated Linoleic Acid in a Male Mouse Model of Metabolic Syndrome. Endocrinology 2017; 158. [PMID: 28651330 PMCID: PMC5659669 DOI: 10.1210/en.2017-00213] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Trans-10, cis-12 conjugated linoleic acid (10,12 CLA) is a dietary fatty acid that promotes weight loss and disproportionate fat loss. Obese mice fed a high-fat, high-sucrose (HFHS) diet containing 10,12 CLA are resistant to weight gain and contain markedly reduced subcutaneous fat and adiponectin, with a concurrent lack of improvement in insulin sensitivity despite significant weight loss. Taken together, 10,12 CLA promotes a phenotype resembling peroxisome proliferator-activated receptor (PPAR)γ antagonism. Because thiazolidinediones such as rosiglitazone (Rosi) are used clinically to improve insulin sensitivity by activating PPARγ, with particular efficacy in subcutaneous white adipose tissue, we hypothesized that Rosi would improve glucose metabolism in mice losing weight with 10,12 CLA. Obese low-density lipoprotein receptor-deficient mice were fed a HFHS control diet, or supplemented with 1% 10,12 CLA with or without Rosi (10 mg/kg) for 8 weeks. Body composition, glucose and insulin tolerance tests, tissue gene expression, and plasma lipid analyses were performed. Mice consuming 10,12 CLA with Rosi lost weight and body fat compared with control groups, but with a healthier redistribution of body fat toward more subcutaneous adipose tissue than with 10,12 CLA alone. Further, Rosi improved 10,12 CLA-mediated insulin resistance parameters and increased plasma and subcutaneous adipose tissue adiponectin levels without adverse effects on plasma or hepatic lipids. We conclude that cotreatment of mice with 10,12 CLA and Rosi promotes fat loss with a healthier fat distribution that leads to improved insulin sensitivity, suggesting that the combination treatment strategy of 10,12 CLA with Rosi could have therapeutic potential for obesity treatment.
Collapse
Affiliation(s)
- Shari Wang
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington 98109
| | - Leela Goodspeed
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington 98109
| | - Katherine E. Turk
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington 98109
| | - Barbara Houston
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington 98109
| | - Laura J. den Hartigh
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington 98109
| |
Collapse
|
16
|
Le NT, Martin JF, Fujiwara K, Abe JI. Sub-cellular localization specific SUMOylation in the heart. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2041-2055. [PMID: 28130202 DOI: 10.1016/j.bbadis.2017.01.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/21/2016] [Accepted: 01/09/2017] [Indexed: 12/27/2022]
Abstract
Although the majority of SUMO substrates are localized in the nucleus, SUMOylation is not limited to nuclear proteins and can be also detected in extra-nuclear proteins. In this review, we will highlight and discuss how SUMOylation in different cellular compartments regulate biological processes. First, we will discuss the key role of SUMOylation of proteins in the extra-nuclear compartment in cardiomyocytes, which is overwhelmingly cardio-protective. On the other hand, SUMOylation of nuclear proteins is generally detrimental to the cardiac function mainly because of the trans-repressive nature of SUMOylation on many transcription factors. We will also discuss the potential role of SUMOylation in epigenetic regulation. In this review, we will propose a new concept that shuttling of SUMO proteases between the nuclear and extra-nuclear compartments without changing their enzymatic activity regulates the extent of SUMOylation in these compartments and determines the response and fate of cardiomyocytes after cardiac insults. Approaches focused specifically to inhibit this shuttling in cardiomyocytes will be necessary to understand the whole picture of SUMOylation and its pathophysiological consequences in the heart, especially after cardiac insults. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure - edited by Jun Ren & Megan Yingmei Zhang.
Collapse
Affiliation(s)
- Nhat-Tu Le
- Department of Cardiology - Research, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - James F Martin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Keigi Fujiwara
- Department of Cardiology - Research, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jun-Ichi Abe
- Department of Cardiology - Research, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| |
Collapse
|
17
|
KVANDOVÁ M, MAJZÚNOVÁ M, DOVINOVÁ I. The Role of PPARγ in Cardiovascular Diseases. Physiol Res 2016; 65:S343-S363. [DOI: 10.33549/physiolres.933439] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The peroxisome proliferator-activated receptors (PPAR) belong to the nuclear superfamily of ligand-activated transcription factors. PPARγ acts as a nutrient sensor that regulates several homeostatic functions. Its disruption can lead to vascular pathologies, disorders of fatty acid/lipid metabolism and insulin resistance. PPARγ can modulate several signaling pathways connected with blood pressure regulation. Firstly, it affects the insulin signaling pathway and endothelial dysfunction by modulation of expression and/or phosphorylation of signaling molecules through the PI3K/Akt/eNOS or MAPK/ET-1 pathways. Secondly, it can modulate gene expression of the renin- angiotensin system – cascade proteins, which potentially slow down the progression of atherosclerosis and hypertension. Thirdly, it can modulate oxidative stress response either directly through PPAR or indirectly through Nrf2 activation. In this context, activation and functioning of PPARγ is very important in the regulation of several disorders such as diabetes mellitus, hypertension and/or metabolic syndrome.
Collapse
Affiliation(s)
| | | | - I. DOVINOVÁ
- Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Bratislava, Slovakia
| |
Collapse
|
18
|
Yu JH, Song SJ, Kim A, Choi Y, Seok JW, Kim HJ, Lee YJ, Lee KS, Kim JW. Suppression of PPARγ-mediated monoacylglycerol O-acyltransferase 1 expression ameliorates alcoholic hepatic steatosis. Sci Rep 2016; 6:29352. [PMID: 27404390 PMCID: PMC4941543 DOI: 10.1038/srep29352] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 06/16/2016] [Indexed: 12/20/2022] Open
Abstract
Alcohol consumption is one of the major causes of hepatic steatosis, fibrosis, cirrhosis, and superimposed hepatocellular carcinoma. Ethanol metabolism alters the NAD(+)/NADH ratio, thereby suppressing the activity of sirtuin family proteins, which may affect lipid metabolism in liver cells. However, it is not clear how long-term ingestion of ethanol eventually causes lipid accumulation in liver. Here, we demonstrate that chronic ethanol ingestion activates peroxisome proliferator-activated receptor γ (PPARγ) and its target gene, monoacylglycerol O-acyltransferase 1 (MGAT1). During ethanol metabolism, a low NAD(+)/NADH ratio repressed NAD-dependent deacetylase sirtuin 1 (SIRT1) activity, concomitantly resulting in increased acetylated PPARγ with high transcriptional activity. Accordingly, SIRT1 transgenic mice exhibited a low level of acetylated PPARγ and were protected from hepatic steatosis driven by alcohol or PPARγ2 overexpression, suggesting that ethanol metabolism causes lipid accumulation through activation of PPARγ through acetylation. Among the genes induced by PPARγ upon alcohol consumption, MGAT1 has been shown to be involved in triglyceride synthesis. Thus, we tested the effect of MGAT1 knockdown in mice following ethanol consumption, and found a significant reduction in alcohol-induced hepatic lipid accumulation. These results suggest that MGAT1 may afford a promising approach to the treatment of fatty liver disease.
Collapse
Affiliation(s)
- Jung Hwan Yu
- Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752, Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752, Korea
| | - Su Jin Song
- Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752, Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752, Korea
| | - Ara Kim
- Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752, Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752, Korea
| | - Yoonjeong Choi
- Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752, Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752, Korea
| | - Jo Woon Seok
- Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752, Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752, Korea
| | - Hyo Jung Kim
- Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - Yoo Jeong Lee
- Division of Metabolic Disease, Center for Biomedical Sciences, National Institutes of Health, Cheongwon-gun, Chungbuk 363-951, Korea
| | - Kwan Sik Lee
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - Jae-Woo Kim
- Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752, Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752, Korea.,Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 120-752, Korea
| |
Collapse
|
19
|
Abstract
Dysregulation of peroxisome proliferator-activated receptor gamma (PPARγ) activity leads to significant alterations in cardiovascular and metabolic regulation. This is most keenly observed by the metabolic syndrome-like phenotypes exhibited by patients carrying mutations in PPARγ. We will summarize recent findings regarding mechanisms of PPARγ regulation in the cardiovascular and nervous systems focusing largely on PPARγ in the smooth muscle, endothelium, and brain. Canonically, PPARγ exerts its effects by regulating the expression of target genes in these cells, and we will discuss mechanisms by which PPARγ targets in the vasculature regulate cardiovascular function. We will also discuss emerging evidence that PPARγ in the brain is a mediator of appetite and obesity. Finally, we will briefly review how novel PPARγ activators control posttranslational modifications of PPARγ and their prospects to offer new therapeutic options for treatment of metabolic diseases without the adverse side effects of thiazolidinediones which strongly activate transcriptional activity of PPARγ.
Collapse
Affiliation(s)
- Madeliene Stump
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, 51 Newton Rd., 2-340 BSB, Iowa City, IA, 52242, USA
- Graduate Program in Neuroscience, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, 51 Newton Rd., 2-340 BSB, Iowa City, IA, 52242, USA
| | - Masashi Mukohda
- Department of Pharmacology and Roy J. and Lucille A. Carver College of Medicine, University of Iowa, 51 Newton Rd., 2-340 BSB, Iowa City, IA, 52242, USA
| | - Chunyan Hu
- Department of Pharmacology and Roy J. and Lucille A. Carver College of Medicine, University of Iowa, 51 Newton Rd., 2-340 BSB, Iowa City, IA, 52242, USA
| | - Curt D Sigmund
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, 51 Newton Rd., 2-340 BSB, Iowa City, IA, 52242, USA.
- Graduate Program in Neuroscience, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, 51 Newton Rd., 2-340 BSB, Iowa City, IA, 52242, USA.
- Department of Pharmacology and Roy J. and Lucille A. Carver College of Medicine, University of Iowa, 51 Newton Rd., 2-340 BSB, Iowa City, IA, 52242, USA.
- UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, 51 Newton Rd., 2-340 BSB, Iowa City, IA, 52242, USA.
| |
Collapse
|
20
|
Choi S, Jung JE, Yang YR, Kim ES, Jang HJ, Kim EK, Kim IS, Lee JY, Kim JK, Seo JK, Kim JM, Park J, Suh PG, Choi JH. Novel phosphorylation of PPARγ ameliorates obesity-induced adipose tissue inflammation and improves insulin sensitivity. Cell Signal 2015; 27:2488-95. [PMID: 26385316 DOI: 10.1016/j.cellsig.2015.09.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 09/09/2015] [Accepted: 09/14/2015] [Indexed: 01/08/2023]
Abstract
Chronic inflammation in adipose tissue is highly associated with insulin resistance. Herein, we demonstrate that a novel modification of PPARγ is strongly associated with inflammatory responses in adipose tissue. c-Src kinase directly phosphorylated PPARγ at Tyr78, and this process was reversed by protein tyrosine phosphatase-1B (PTP-1B). In adipocytes, phosphorylation of PPARγ suppressed the expression of pro-inflammatory genes as well as the secretion of chemokines and cytokines, thus reducing macrophage migration. Importantly, pharmacological inhibition of c-Src kinase aggravated insulin resistance in obese mice with a concomitant increase in the expression of pro-inflammatory genes in adipose tissue. These data strongly suggest that PPARγ phosphorylation is the key regulatory mechanism of the inflammatory response in adipose tissue, which is highly associated with glucose tolerance and insulin sensitivity. Furthermore, these data increase our understanding of the mechanical aspects of developing novel anti-diabetic drugs targeting PPARγ phosphorylation.
Collapse
Affiliation(s)
- Sunsil Choi
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Ji-Eun Jung
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Yong Ryoul Yang
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Eun-Sun Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Hyun-Jun Jang
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Eung-Kyun Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Il Shin Kim
- UNIST Central Research Facilities, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Joo-Young Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Joong Kwan Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Jeong Kon Seo
- UNIST Central Research Facilities, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Jung-Min Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Jiyoung Park
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Pann-Ghill Suh
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea
| | - Jang Hyun Choi
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Korea.
| |
Collapse
|
21
|
Abstract
There has been an upsurge of interest in the adipocyte coincident with the onset of the obesity epidemic and the realization that adipose tissue plays a major role in the regulation of metabolic function. The past few years, in particular, have seen significant changes in the way that we classify adipocytes and how we view adipose development and differentiation. We have new perspective on the roles played by adipocytes in a variety of homeostatic processes and on the mechanisms used by adipocytes to communicate with other tissues. Finally, there has been significant progress in understanding how these relationships are altered during metabolic disease and how they might be manipulated to restore metabolic health.
Collapse
Affiliation(s)
- Evan D Rosen
- Division of Endocrinology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; Departments of Genetics and Cell Biology, Harvard Medical School, Boston, MA 02215, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
| | - Bruce M Spiegelman
- Departments of Genetics and Cell Biology, Harvard Medical School, Boston, MA 02215, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.
| |
Collapse
|
22
|
Diezko R, Suske G. Ligand binding reduces SUMOylation of the peroxisome proliferator-activated receptor γ (PPARγ) activation function 1 (AF1) domain. PLoS One 2013; 8:e66947. [PMID: 23826177 PMCID: PMC3691213 DOI: 10.1371/journal.pone.0066947] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 05/10/2013] [Indexed: 12/12/2022] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-activated nuclear receptor regulating adipogenesis, glucose homeostasis and inflammatory responses. The activity of PPARγ is controlled by post-translational modifications including SUMOylation and phosphorylation that affects its biological and molecular functions. Several important aspects of PPARγ SUMOylation including SUMO isoform-specificity and the impact of ligand binding on SUMOylation remain unresolved or contradictory. Here, we present a comprehensive study of PPARγ1 SUMOylation. We show that PPARγ1 can be modified by SUMO1 and SUMO2. Mutational analyses revealed that SUMOylation occurs exclusively within the N-terminal activation function 1 (AF1) domain predominantly at lysines 33 and 77. Ligand binding to the C-terminal ligand-binding domain (LBD) of PPARγ1 reduces SUMOylation of lysine 33 but not of lysine 77. SUMOylation of lysine 33 and lysine 77 represses basal and ligand-induced activation by PPARγ1. We further show that lysine 365 within the LBD is not a target for SUMOylation as suggested in a previous report, but it is essential for full LBD activity. Our results suggest that PPARγ ligands negatively affect SUMOylation by interdomain communication between the C-terminal LBD and the N-terminal AF1 domain. The ability of the LBD to regulate the AF1 domain may have important implications for the evaluation and mechanism of action of therapeutic ligands that bind PPARγ.
Collapse
Affiliation(s)
- Rolf Diezko
- Institute of Molecular Biology and Tumor Research, Philipps-University Marburg, Marburg, Germany
| | - Guntram Suske
- Institute of Molecular Biology and Tumor Research, Philipps-University Marburg, Marburg, Germany
- * E-mail:
| |
Collapse
|
23
|
Ahmadian M, Suh JM, Hah N, Liddle C, Atkins AR, Downes M, Evans RM. PPARγ signaling and metabolism: the good, the bad and the future. Nat Med 2013; 19:557-66. [PMID: 23652116 PMCID: PMC3870016 DOI: 10.1038/nm.3159] [Citation(s) in RCA: 1555] [Impact Index Per Article: 141.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 03/06/2013] [Indexed: 11/09/2022]
Abstract
Thiazolidinediones (TZDs) are potent insulin sensitizers that act through the nuclear receptor peroxisome proliferator-activated receptor-γ (PPARγ) and are highly effective oral medications for type 2 diabetes. However, their unique benefits are shadowed by the risk for fluid retention, weight gain, bone loss and congestive heart failure. This raises the question as to whether it is possible to build a safer generation of PPARγ-specific drugs that evoke fewer side effects while preserving insulin-sensitizing potential. Recent studies that have supported the continuing physiologic and therapeutic relevance of the PPARγ pathway also provide opportunities to develop newer classes of molecules that reduce or eliminate adverse effects. This review highlights key advances in understanding PPARγ signaling in energy homeostasis and metabolic disease and also provides new explanations for adverse events linked to TZD-based therapy.
Collapse
Affiliation(s)
- Maryam Ahmadian
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, California, USA
| | | | | | | | | | | | | |
Collapse
|
24
|
Kim TH, Kim MY, Jo SH, Park JM, Ahn YH. Modulation of the transcriptional activity of peroxisome proliferator-activated receptor gamma by protein-protein interactions and post-translational modifications. Yonsei Med J 2013; 54:545-59. [PMID: 23549795 PMCID: PMC3635639 DOI: 10.3349/ymj.2013.54.3.545] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ) belongs to a nuclear receptor superfamily; members of which play key roles in the control of body metabolism principally by acting on adipose tissue. Ligands of PPARγ, such as thiazolidinediones, are widely used in the treatment of metabolic syndromes and type 2 diabetes mellitus (T2DM). Although these drugs have potential benefits in the treatment of T2DM, they also cause unwanted side effects. Thus, understanding the molecular mechanisms governing the transcriptional activity of PPARγ is of prime importance in the development of new selective drugs or drugs with fewer side effects. Recent advancements in molecular biology have made it possible to obtain a deeper understanding of the role of PPARγ in body homeostasis. The transcriptional activity of PPARγ is subject to regulation either by interacting proteins or by modification of the protein itself. New interacting partners of PPARγ with new functions are being unveiled. In addition, post-translational modification by various cellular signals contributes to fine-tuning of the transcriptional activities of PPARγ. In this review, we will summarize recent advancements in our understanding of the post-translational modifications of, and proteins interacting with, PPARγ, both of which affect its transcriptional activities in relation to adipogenesis.
Collapse
Affiliation(s)
- Tae-Hyun Kim
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Korea
- Integrative Genomic Research Center for Metabolic Regulation, Yonsei University College of Medicine, Seoul, Korea
| | - Mi-Young Kim
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Korea
- Integrative Genomic Research Center for Metabolic Regulation, Yonsei University College of Medicine, Seoul, Korea
| | - Seong-Ho Jo
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Korea
- Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul, Korea
- Integrative Genomic Research Center for Metabolic Regulation, Yonsei University College of Medicine, Seoul, Korea
| | - Joo-Man Park
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Korea
- Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul, Korea
- Integrative Genomic Research Center for Metabolic Regulation, Yonsei University College of Medicine, Seoul, Korea
| | - Yong-Ho Ahn
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Korea
- Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul, Korea
- Integrative Genomic Research Center for Metabolic Regulation, Yonsei University College of Medicine, Seoul, Korea
| |
Collapse
|
25
|
Baczyk D, Drewlo S, Kingdom JCP. Emerging role of SUMOylation in placental pathology. Placenta 2013; 34:606-12. [PMID: 23628505 DOI: 10.1016/j.placenta.2013.03.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 03/08/2013] [Accepted: 03/27/2013] [Indexed: 10/26/2022]
Abstract
INTRODUCTION Small ubiquitin-like modifiers (SUMO) conjugate to target proteins in a dynamic, reversible manner to function as post-translational modifiers. SUMOylation of target proteins can impinge on their localization, in addition to their activity or stability. Differential expression of deSUMOylating enzymes (SENP 1 and 2) contributes to altered mammalian placental development and function in mice. Severe preeclampsia (sPE) is associated with abnormal placental development and chronic ischemic injury. Extra- and intracellular stimuli/stressors that include hypoxic-activated pathways are known modulators of SUMOylation. In this current study we hypothesized that placentas from sPE patients will display up regulation in the SUMO regulatory pathway. METHODS Utilizing qRT-PCR, immuno-blotting and Western techniques, we determined the expression levels of SUMO pathway genes in healthy and diseased placentas. We also exposed placental explants to hypoxia to study the effect on the SUMOylation pathway. RESULTS We observed steady-state expression of SUMO1-3, SUMO-conjugated enzyme-UBC9 and deSUMOylating enzymes - SENPs, throughout normal gestation. An elevated level of free SUMO1-3 and SUMO-protein conjugates was observed in sPE placentas. Furthermore, placental UBC9 levels were strikingly increased in the same sPE patients. Hypoxia-induced SUMOylation in first trimester placental explants. DISCUSSION Our data demonstrate an elevated steady-state of SUMOylation in sPE placentas compared with gestational aged-matched controls. The observed hyper-SUMOylation in sPE placentas correlates with elevated expression of UBC9 rather than with reduced expression of SENPs Hypoxia may contribute to alterations in placental SUMOylation pathway. CONCLUSION Increased placental SUMOylation may contribute to the pathogenesis of serious placental pathology that causes extreme preterm birth.
Collapse
Affiliation(s)
- D Baczyk
- Research Centre for Women's and Infants' Health, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, University of Toronto, 25 Orde Street, Toronto, Ontario M5T 3H7, Canada.
| | | | | |
Collapse
|
26
|
Chen W, Chang B, Wu X, Li L, Sleeman M, Chan L. Inactivation of Plin4 downregulates Plin5 and reduces cardiac lipid accumulation in mice. Am J Physiol Endocrinol Metab 2013; 304:E770-9. [PMID: 23423172 PMCID: PMC3625749 DOI: 10.1152/ajpendo.00523.2012] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Plin4 is a lipid droplet protein (LDP) found predominantly in white adipose tissue (WAT). The Plin4 gene is immediately downstream of the Plin5 gene; the two genes exhibit distinct though overlapping tissue expression patterns. Plin4 is absent in brown adipose tissue (BAT) and liver and expressed at low levels in heart and skeletal muscle, whereas Plin5 is highly expressed in these oxidative tissues but at a low level in WAT. The physiological role of Plin4 remains unclear. We have generated Plin4(-/-) mice by gene targeting. Loss of Plin4 has no effect on body weight or composition or on adipose mass or development. However, the triacylglycerol (TAG) content in heart, but not other oxidative tissues such as BAT, soleus muscle, and liver, is markedly reduced in Plin4(-/-) mice. The heart of Plin4(-/-) mice displays reduced Plin5 mRNA and protein levels (by ~38 and 87%, respectively, vs. wild-type) but unchanged mRNA levels of other perilipin family genes (Plin2 and Plin3) or genes involved in glucose and lipid metabolism. Despite reduced cardiac TAG level, both young and aged Plin4(-/-) mice maintain normal heart function as wild-type mice, as measured by echocardiography. Interestingly, Plin4 deficiency prevents the lipid accumulation in the heart that normally occurs after a prolonged (48-h) fast. It also protects the heart from cardiac steatosis induced by high-fat diet or when Plin4(-/-) mice are bred into Lep(-/-) obese background. In conclusion, inactivation of Plin4 downregulates Plin5 and reduces cardiac lipid accumulation in mice.
Collapse
Affiliation(s)
- Weiqin Chen
- Diabetes and Endocrinology Research Center, Section of Diabetes and Endocrinology, Departments of Medicine, Molecular and Cellular Biology and Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | | | | | | | | | | |
Collapse
|
27
|
Hollman DAA, Milona A, van Erpecum KJ, van Mil SWC. Anti-inflammatory and metabolic actions of FXR: insights into molecular mechanisms. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:1443-52. [PMID: 22820415 DOI: 10.1016/j.bbalip.2012.07.004] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 06/29/2012] [Accepted: 07/05/2012] [Indexed: 01/03/2023]
Abstract
The farnesoid X receptor (FXR) is a ligand-activated transcription factor belonging to the nuclear receptor (NR) superfamily. FXR plays an important role in positively regulating genes (transactivation) involved in bile acid homeostasis, fat and glucose metabolism. Recently, it has become clear that an additional important role for FXR consists of downregulating genes involved in inflammation. Because of this broad spectrum of regulated genes, therapeutically targeting FXR with full agonists will likely result in adverse side effects, in line with what is described for other NRs. It may therefore be necessary to develop selective FXR modulators. However, the molecular mechanisms that distinguish between FXR-mediated transactivation and transrepression are currently unknown. For other NRs, post-translational modifications such as SUMOylation and phosphorylation have been reported to be unique to either transactivation or transrepression. Here, we review current knowledge on post-translational regulation of FXR with respect to transactivation and transrepression. Ultimately, increased understanding of the different mechanisms of transactivation and transrepression of nuclear receptors will aid in the development of NR drugs with fewer side effects.
Collapse
Affiliation(s)
- Danielle A A Hollman
- Department of Metabolic Diseases, UMC Utrecht and Netherlands Metabolomics Centre, The Netherlands
| | | | | | | |
Collapse
|
28
|
Harmon GS, Lam MT, Glass CK. PPARs and lipid ligands in inflammation and metabolism. Chem Rev 2012; 111:6321-40. [PMID: 21988241 DOI: 10.1021/cr2001355] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Gregory S Harmon
- Department of Medicine, Division of Digestive Diseases, University of California-Los Angeles, Los Angeles, California 90095, USA
| | | | | |
Collapse
|
29
|
Gurevich I, Zhang C, Encarnacao PC, Struzynski CP, Livings SE, Aneskievich BJ. PPARγ and NF-κB regulate the gene promoter activity of their shared repressor, TNIP1. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1819:1-15. [PMID: 22001530 PMCID: PMC3249470 DOI: 10.1016/j.bbagrm.2011.09.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 09/27/2011] [Accepted: 09/30/2011] [Indexed: 11/27/2022]
Abstract
Human TNFAIP3 interacting protein 1 (TNIP1) has diverse functions including support of HIV replication through its interaction with viral Nef and matrix proteins, reduction of TNFα-induced signaling through its interaction with NF-κB pathway proteins, and corepression of agonist-bound retinoic acid receptors and peroxisome proliferator-activated receptors (PPAR). The wide tissue distribution of TNIP1 provides the opportunity to influence numerous cellular responses in these roles and defining control of TNIP1 expression would be central to improved understanding of its impact on cell function. We cloned 6kb of the human TNIP1 promoter and performed predictive and functional analyses to identify regulatory elements. The promoter region proximal to the transcription start site is GC-rich without a recognizable TATA box. In contrast to this proximal ~500bp region, 6kb of the promoter increased reporter construct constitutive activity over five-fold. Throughout the 6kb length, in silico analysis identified several potential binding sites for both constitutive and inducible transcription factors; among the latter were candidate NF-κB binding sequences and peroxisome proliferator response elements (PPREs). We tested NF-κB and PPAR regulation of the endogenous TNIP1 gene and cloned promoter by expression studies, electrophoretic mobility shift assays, and chromatin immunoprecipitations. We validated NF-κB sites in the TNIP1 promoter proximal and distal regions as well as one PPRE in the distal region. The ultimate control of the TNIP1 promoter is likely to be a combination of constitutive transcription factors and those subject to activation such as NF-κB and PPAR.
Collapse
Affiliation(s)
- Igor Gurevich
- Graduate Program in Pharmacology & Toxicology, University of Connecticut, Storrs, CT 06269-3092; USA
| | - Carmen Zhang
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269-3092; USA
| | - Priscilla C. Encarnacao
- Graduate Program in Pharmacology & Toxicology, University of Connecticut, Storrs, CT 06269-3092; USA
| | - Charles P. Struzynski
- Doctor of Pharmacy Program, School of Pharmacy, University of Connecticut, Storrs, CT 06269-3092; USA
| | - Sarah E. Livings
- Doctor of Pharmacy Program, School of Pharmacy, University of Connecticut, Storrs, CT 06269-3092; USA
| | - Brian J. Aneskievich
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269-3092; USA
- Center for Regenerative Biology, University of Connecticut, Storrs, CT 06269-3092; USA
| |
Collapse
|
30
|
Cheng CF, Lian WS, Chen SH, Lai PF, Li HF, Lan YF, Cheng WTK, Lin H. Protective effects of adiponectin against renal ischemia-reperfusion injury via prostacyclin-PPARα-heme oxygenase-1 signaling pathway. J Cell Physiol 2011; 227:239-49. [PMID: 21412771 DOI: 10.1002/jcp.22726] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Adiponectin (APN), a circulating adipose-derived hormone that regulates inflammation and energy metabolism, has beneficial effects on the cardiovascular disorders. Serum APN levels are lower in patients with coronary artery disease and higher in patients with chronic kidney disease. However, the precise role of APN in acute reno-vascular disease is not clear. Results of the present study show that serum APN concentration decreased after renal ischemia reperfusion (I/R) injury in mice. In addition, I/R-induced renal dysfunction (elevated serum creatinine and urea levels), inflammation (number of infiltrating neutrophils, myeloperoxidase activity), and apoptotic responses (apoptotic cell number and caspase-3 activation) were attenuated in APN-treated compared to control mice. Molecular and biochemical analysis revealed that APN up-regulates heme oxygenase-1 (HO-1) via peroxisome-proliferator-activated-receptor-α (PPARα) dependent pathway which is mediated through the enhancement of COX-2 and 6-keto PGF1α expression. Chromatin immune-precipitation assay demonstrated that APN increases the binding activity of PPARα to PPRE region of HO-1 promoter. Furthermore, APN induced HO-1 expression was only found in wild-type but not in PPARα gene deleted mice. This provides in vivo evidence that APN mediated HO-1 expression depends on PPARα regulation. In conclusion, our results provide a novel APN mediated prostacyclin-PPARα-HO-1 signaling pathway in protecting renal I/R injury.
Collapse
Affiliation(s)
- Ching-Feng Cheng
- Department of Medical Research, Tzu Chi General Hospital, Hualien, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Wadosky KM, Willis MS. The story so far: post-translational regulation of peroxisome proliferator-activated receptors by ubiquitination and SUMOylation. Am J Physiol Heart Circ Physiol 2011; 302:H515-26. [PMID: 22037188 DOI: 10.1152/ajpheart.00703.2011] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Many studies have implicated the peroxisome proliferator-activated receptor (PPAR) family of nuclear receptor transcription factors in regulating cardiac substrate metabolism and ATP generation. Recently, evidence from a variety of cell culture and organ systems has implicated ubiquitin and small ubiquitin-like modifier (SUMO) conjugation as post-translational modifications that regulate the activity of PPAR transcription factors and their coreceptors/coactivators. Here we introduce the ubiquitin and SUMO conjugation systems and extensively review how they have been shown to regulate all three PPAR isoforms (PPARα, PPARβ/δ, and PPARγ) in addition to the retinoid X receptor and PPARγ coactivator-1α subunits of the larger PPAR transcription factor complex. We then present how the specific ubiquitin (E3) ligases have been implicated and review emerging evidence that post-translational modifications of PPARs with ubiquitin and/or SUMO may play a role in cardiac disease. Because PPAR activity is perturbed in a variety of forms of heart disease and specific proteins regulate this process (E3 ligases), this may be a fruitful area of investigation with respect to finding new therapeutic targets.
Collapse
Affiliation(s)
- Kristine M Wadosky
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, North Carolina 27599-7525, USA
| | | |
Collapse
|
32
|
Omega-3 Fatty Acids and PPARgamma in Cancer. PPAR Res 2011; 2008:358052. [PMID: 18769551 PMCID: PMC2526161 DOI: 10.1155/2008/358052] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Revised: 05/30/2008] [Accepted: 06/24/2008] [Indexed: 01/25/2023] Open
Abstract
Omega-3 (or n-3) polyunsaturated fatty acids (PUFAs) and their metabolites are natural ligands for peroxisome proliferator receptor activator (PPAR)gamma and, due to the effects of PPARgamma on cell proliferation, survival, and differentiation, are potential anticancer agents. Dietary intake of omega-3 PUFAs has been associated with a reduced risk of certain cancers in human populations and in animal models. In vitro studies have shown that omega-3 PUFAs inhibit cell proliferation and induce apoptosis in cancer cells through various pathways but one of which involves PPARgamma activation. The differential activation of PPARgamma and PPARgamma-regulated genes by specific dietary fatty acids may be central to their distinct roles in cancer. This review summarizes studies relating PUFAs to PPARgamma and cancer and offers a new paradigm relating an n-3 PUFA through PPARgamma to the expression of the cell surface proteoglycan, syndecan-1, and to the death of cancer cells.
Collapse
|
33
|
Berrabah W, Aumercier P, Lefebvre P, Staels B. Control of nuclear receptor activities in metabolism by post-translational modifications. FEBS Lett 2011; 585:1640-50. [PMID: 21486568 DOI: 10.1016/j.febslet.2011.03.066] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Accepted: 03/30/2011] [Indexed: 12/24/2022]
Abstract
Nuclear receptors (NRs) are molecular transducers of endocrine and dietary signals allowing tissues to adapt their transcriptional responses to endogenous or exogenous cues. These signals act in many cases as specific ligands, converting of NRs into transcriptionally active molecules. This on-off mechanism needs, however, to be finely tuned with respect to the tissue environment and adjusted to the organism needs. These subtle adjustments of NR transcriptional activity are brought about by post-translational modifications (PTMs), which can be, in the case of orphan NRs, the sole regulatory mechanism. The role of PTMs, with a more specific focus on phosphorylation, affecting the functions of NR controlling metabolic events is described in this review.
Collapse
Affiliation(s)
- Wahiba Berrabah
- Université Lille Nord de France, INSERM, U1011, Lille, France
| | | | | | | |
Collapse
|
34
|
Koltes D, Spurlock D. Coordination of lipid droplet-associated proteins during the transition period of Holstein dairy cows. J Dairy Sci 2011; 94:1839-48. [DOI: 10.3168/jds.2010-3769] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Accepted: 01/07/2011] [Indexed: 01/21/2023]
|
35
|
Abstract
Normally macrophages localized in the arterial vessel wall perform the "reverse transfer" of cholesterol, which includes endocytosis of low density lipoproteins (LDL), cholesterol transfer to newly formed high density lipoprotein particles, and their following elimination by the liver. The homeostatic function of macrophages for cholesterol involves a system of lipid sensors. Oxysterol sensors LXRs, oxysterol and cholesterol sensors INSIG and SCAP acting through controlled transcription factors SREBP, as well as sensors for oxidized fatty acids and their derivatives, PPAR, are the best studied. Activation of LXR and PPAR is also accompanied by inhibition of macrophage functions related to inflammation. Accumulation of oxidized and otherwise modified LDL in the subendothelial space induced by endothelium injury, infection, or other pathogenic factors instead of stimulation of the homeostatic functions of macrophages leads to their weakening with a concurrent increase in the inflammatory potential of these cells. These shifts seem to drive the transformation of macrophages into foam cells, which form the core of sclerotic plaques. The intervention of another lipid sensor, TLR4, can trigger such a radical change in the functional activity of macrophages. The interaction of modified LDL with this signaling receptor results in inhibition of the homeostatic oxysterol signaling, induction of additional LDL transporters, and activation of the phagocytic function of macrophages. The re-establishment of cholesterol homeostasis under these circumstances can be achieved by administration of LXR and PPARgamma agonists. Therefore, it is urgent to design ligands with reduced side effects.
Collapse
|
36
|
Straub BK, Herpel E, Singer S, Zimbelmann R, Breuhahn K, Macher-Goeppinger S, Warth A, Lehmann-Koch J, Longerich T, Heid H, Schirmacher P. Lipid droplet-associated PAT-proteins show frequent and differential expression in neoplastic steatogenesis. Mod Pathol 2010; 23:480-92. [PMID: 20081801 DOI: 10.1038/modpathol.2009.191] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In many human cancers, lipogenic pathways are activated; in some tumors, such as hepatocellular carcinoma, this is reflected by the presence of visible lipid droplets. Yet, the biology of steatogenesis in malignant tumors is largely unknown. We have recently shown that lipid droplet-associated proteins of the PAT-family, named after their constituents perilipin (perilipin 1), adipophilin (perilipin 2), and TIP47 (perilipin 3) are differentially expressed in hepatic steatogenesis. We have comprehensively investigated PAT-expression in neoplastic steatogenesis as well as in respective normal tissues with immunohistology and electron microscopy as well as protein biochemical and molecular biological methods. By staining for PAT-proteins, we found lipid droplet accumulation to be a frequent phenomenon of carcinoma cells. Although adipophilin and TIP47 stained almost ubiquitously the rim of lipid droplets in various tumor types, especially those with clear cell phenotype, perilipin was restricted to lipid droplets of hepatocellular adenoma and carcinoma, sebaceous adenoma and carcinoma, and lipomatous tumors. In hepatocellular carcinoma, perilipin, adipophilin, and TIP47 were coexpressed, and showed regional heterogeneity with a predominantly mutually exclusive localization pattern. In step-wise carcinogenesis, adipophilin expression correlated with the proliferation rate and was upregulated during early tumorigenesis, whereas perilipin was often lost during hepatocarcinogenesis. In conclusion, expression analysis of PAT-proteins showed that by far more carcinomas contain (PAT-positive) lipid droplets than expected by conventional light microscopy. PAT-proteins, such as perilipin, are differentially expressed in different tumor types and thus may support diagnostic considerations. Because inhibition of lipogenesis has been shown to exert antineoplastic effects, PAT-proteins may represent targets for interventive strategies.
Collapse
Affiliation(s)
- Beate K Straub
- Department of General Pathology, Institute of Pathology, University Clinic Heidelberg, Heidelberg, Germany.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Anti-apoptotic Actions of PPAR-γ Against Ischemic Stroke. Mol Neurobiol 2010; 41:180-6. [DOI: 10.1007/s12035-010-8103-y] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 01/14/2010] [Indexed: 12/25/2022]
|
38
|
Pourcet B, Pineda-Torra I, Derudas B, Staels B, Glineur C. SUMOylation of human peroxisome proliferator-activated receptor alpha inhibits its trans-activity through the recruitment of the nuclear corepressor NCoR. J Biol Chem 2009; 285:5983-92. [PMID: 19955185 DOI: 10.1074/jbc.m109.078311] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The nuclear receptor peroxisome proliferator-activated receptor alpha (PPARalpha) is a key regulator of genes implicated in lipid homeostasis and inflammation. PPARalpha trans-activity is enhanced by recruitment of coactivators such as SRC1 and CBP/p300 and is inhibited by binding of corepressors such as NCoR and SMRT. In addition to ligand binding, PPARalpha activity is regulated by post-translational modifications such as phosphorylation and ubiquitination. In this report, we demonstrate that hPPARalpha is SUMOylated by SUMO-1 on lysine 185 in the hinge region. The E2-conjugating enzyme Ubc9 and the SUMO E3- ligase PIASy are implicated in this process. In addition, ligand treatment decreases the SUMOylation rate of hPPARalpha. Finally, our results demonstrate that SUMO-1 modification of hPPARalpha down-regulates its trans-activity through the specific recruitment of corepressor NCoR but not SMRT leading to the differential expression of a subset of PPARalpha target genes. In conclusion, hPPARalpha SUMOylation on lysine 185 down-regulates its trans-activity through the selective recruitment of NCoR.
Collapse
|
39
|
Shin J, Li B, Davis ME, Suh Y, Lee K. Comparative analysis of fatty acid-binding protein 4 promoters: Conservation of peroxisome proliferator-activated receptor binding sites1. J Anim Sci 2009; 87:3923-34. [DOI: 10.2527/jas.2009-2124] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
|
40
|
Yoshida H. ER stress response, peroxisome proliferation, mitochondrial unfolded protein response and Golgi stress response. IUBMB Life 2009; 61:871-9. [PMID: 19504573 DOI: 10.1002/iub.229] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The endoplasmic reticulum (ER) response has been thought a cytoprotective mechanism to cope with accumulation of unfolded proteins in the ER. Recent progress has made a quantum leap revealing that ER stress response can be regarded as an autoregulatory system adjusting the ER capacity to cellular demand. This Copernican change raised a novel fundamental question in cell biology: how do cells regulate the capacity of each organelle in accordance with cellular needs? Although this fundamental question has not been fully addressed yet, research about each organelle has been advancing. The proliferation of the peroxisome is regulated by the PPAR alpha pathway, whereas the abundance of mitochondria appears to be regulated by mitochondrial retrograde signaling and the mitochondrial unfolded protein response. The functional capacity of the Golgi apparatus may be regulated by the mechanism of the Golgi stress response. These observations strongly suggest the existence of an elaborate network of organelle autoregulation in eukaryotic cells.
Collapse
Affiliation(s)
- Hiderou Yoshida
- Department of Biophysics, Graduate School of Science, Kyoto University, Japan.
| |
Collapse
|
41
|
Bugge A, Grøntved L, Aagaard MM, Borup R, Mandrup S. The PPARgamma2 A/B-domain plays a gene-specific role in transactivation and cofactor recruitment. Mol Endocrinol 2009; 23:794-808. [PMID: 19282365 DOI: 10.1210/me.2008-0236] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We have previously shown that adenoviral expression of peroxisome proliferator-activated receptors (PPARs) leads to rapid establishment of transcriptionally active complexes and activation of target gene expression within 5-8 h after transduction. Here we have used the adenoviral delivery system combined with expression array analysis to identify novel putative PPARgamma target genes in murine fibroblasts and to determine the role of the A/B-domain in PPARgamma-mediated transactivation of genomic target genes. Of the 257 genes found to be induced by PPARgamma2 expression, only 25 displayed A/B-domain dependency, i.e. significantly reduced induction in the cells expressing the truncated PPARgamma lacking the A/B-domain (PPARgammaCDE). Nine of the 25 A/B-domain-dependent genes were involved in lipid storage, and in line with this, triglyceride accumulation was considerably decreased in the cells expressing PPARgammaCDE compared with cells expressing full-length PPARgamma2. Using chromatin immunoprecipitation, we demonstrate that PPARgamma binding to genomic target sites and recruitment of the mediator component TRAP220/MED1/PBP/DRIP205 is not affected by the deletion of the A/B-domain. By contrast, the PPARgamma-mediated cAMP response element-binding protein (CREB)-binding protein (CBP) and p300 recruitment to A/B-domain-dependent target genes is compromised by deletion of the A/B-domain. These results indicate that the A/B-domain of PPARgamma2 is specifically involved in the recruitment or stabilization of CBP- and p300-containing cofactor complexes to a subset of target genes.
Collapse
Affiliation(s)
- Anne Bugge
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | | | | | | | | |
Collapse
|
42
|
van Beekum O, Fleskens V, Kalkhoven E. Posttranslational modifications of PPAR-gamma: fine-tuning the metabolic master regulator. Obesity (Silver Spring) 2009; 17:213-9. [PMID: 19169221 DOI: 10.1038/oby.2008.473] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Olivier van Beekum
- Department of Metabolic and Endocrine Diseases, University Medical Centre Utrecht, Utrecht, The Netherlands
| | | | | |
Collapse
|
43
|
Abstract
OBJECTIVE Peroxisome proliferator-activated receptor gamma (PPARgamma) is a transcription factor that plays an important role in adipocyte gene expression. Previous studies from our laboratory and others have shown that PPARgamma can be ubiquitin modified and targeted to the proteasome for degradation in response to transcriptional activation. In this study, we determined whether other degradation pathways contributed to the tumor necrosis factor alpha (TNFalpha)-induced degradation of PPARgamma proteins in 3T3-L1 adipocytes. METHODS AND PROCEDURES In these studies, 3T3-L1 cells were studied by performing subcellular fractionations and western blotting after various TNFalpha treatments. Whole tissue extracts from rat adipose tissue were also used to examine PPARgamma degradation. RESULTS We observed that TNFalpha can induce a caspase-mediated degradation of PPARgamma proteins in the presence of cycloheximide. The caspase-mediated degradation of both PPARgamma1 and PPARgamma2 resulted in the generation of a specific 44-kd cleavage product. The specific cleavage product was unaffected by proteasome inhibitors, but was repressed by a general caspase inhibitor. Use of several specific caspase inhibitors revealed that caspase-1 was activated following treatment with TNFalpha and cycloheximide (CH), and inhibition of caspase-1 blocked the cleavage of PPARgamma proteins in cultured adipocytes. In addition, a similar PPARgamma degradation product was observed in rodent adipose tissue. DISCUSSION In summary, this is the first study to demonstrate that PPARgamma levels can be modulated by caspase activity.
Collapse
Affiliation(s)
- Fang He
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | | | | |
Collapse
|
44
|
Li Y, Wang Z, Furukawa N, Escaron P, Weiszmann J, Lee G, Lindstrom M, Liu J, Liu X, Xu H, Plotnikova O, Prasad V, Walker N, Learned RM, Chen JL. T2384, a Novel Antidiabetic Agent with Unique Peroxisome Proliferator-activated Receptor γ Binding Properties. J Biol Chem 2008; 283:9168-76. [DOI: 10.1074/jbc.m800104200] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|