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Wagner N, Wagner KD. Peroxisome Proliferator-Activated Receptors and the Hallmarks of Cancer. Cells 2022; 11:cells11152432. [PMID: 35954274 PMCID: PMC9368267 DOI: 10.3390/cells11152432] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/02/2022] [Accepted: 08/04/2022] [Indexed: 12/11/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) function as nuclear transcription factors upon the binding of physiological or pharmacological ligands and heterodimerization with retinoic X receptors. Physiological ligands include fatty acids and fatty-acid-derived compounds with low specificity for the different PPAR subtypes (alpha, beta/delta, and gamma). For each of the PPAR subtypes, specific pharmacological agonists and antagonists, as well as pan-agonists, are available. In agreement with their natural ligands, PPARs are mainly focused on as targets for the treatment of metabolic syndrome and its associated complications. Nevertheless, many publications are available that implicate PPARs in malignancies. In several instances, they are controversial for very similar models. Thus, to better predict the potential use of PPAR modulators for personalized medicine in therapies against malignancies, it seems necessary and timely to review the three PPARs in relation to the didactic concept of cancer hallmark capabilities. We previously described the functions of PPAR beta/delta with respect to the cancer hallmarks and reviewed the implications of all PPARs in angiogenesis. Thus, the current review updates our knowledge on PPAR beta and the hallmarks of cancer and extends the concept to PPAR alpha and PPAR gamma.
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Affiliation(s)
- Nicole Wagner
- Correspondence: (N.W.); (K.-D.W.); Tel.: +33-489-153-713 (K.-D.W.)
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Lee EJ, Won JP, Lee HG, Kim E, Hur J, Lee WJ, Hwang JS, Seo HG. PPARδ Inhibits Hyperglycemia-Triggered Senescence of Retinal Pigment Epithelial Cells by Upregulating SIRT1. Antioxidants (Basel) 2022; 11:antiox11061207. [PMID: 35740104 PMCID: PMC9219651 DOI: 10.3390/antiox11061207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/09/2022] [Accepted: 06/16/2022] [Indexed: 02/04/2023] Open
Abstract
Emerging evidence shows that peroxisome proliferator-activated receptor delta (PPARδ) plays a pivotal role in cellular aging. However, its function in retinal disease processes such as hyperglycemia-associated diabetic retinopathy is unclear. Here, we demonstrate that PPARδ inhibits premature senescence of retinal pigment epithelial (RPE) cells induced by high glucose (HG) through SIRT1 upregulation. A specific ligand GW501516-activation of PPARδ suppressed premature senescence and production of reactive oxygen species induced by HG in ARPE-19 cells, a spontaneously arising human RPE cell line. These effects were accompanied by the regulation of the premature senescence-associated genes p53, p21, and SMP-30. Furthermore, GW501516-activated PPARδ almost completely abolished the effects of HG treatment on the formation of phosphorylated H2A histone family member X (γ-H2A.X) foci, a molecular marker of aging. These inhibitory effects of GW501516 were significantly reversed in ARPE-19 cells stably expressing small hairpin RNA targeting PPARδ. Notably, GW501516 significantly increased the mRNA and protein levels of SIRT1, indicating that GW501516-activated PPARδ exerted its beneficial effects through SIRT1. In addition, GW501516 restored HG-suppressed SIRT1 expression, corroborating the role of SIRT1 in the anti-senescence function of PPARδ. The effects of PPARδ on HG-induced premature senescence and the expression of the senescence-associated genes p53, p21, and SMP-30 were mimicked by the SIRT1 activator resveratrol, but blocked by the SIRT1 inhibitor sirtinol. Collectively, these results indicate that GW501516-activated PPARδ inhibits HG-triggered premature senescence of RPE cells by modulating SIRT1 signaling.
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Xiao L, Wang N. PPAR-δ: A key nuclear receptor in vascular function and remodeling. J Mol Cell Cardiol 2022; 169:1-9. [DOI: 10.1016/j.yjmcc.2022.04.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/29/2022] [Accepted: 04/25/2022] [Indexed: 12/08/2022]
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Kim SG, Sung JY, Kim JR, Choi HC. Fisetin-induced PTEN expression reverses cellular senescence by inhibiting the mTORC2-Akt Ser473 phosphorylation pathway in vascular smooth muscle cells. Exp Gerontol 2021; 156:111598. [PMID: 34695518 DOI: 10.1016/j.exger.2021.111598] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/12/2021] [Accepted: 10/16/2021] [Indexed: 12/26/2022]
Abstract
Cellular senescence is caused by a wide range of intracellular and extracellular stimuli and influences physiological functions, leading to the progression of age-related diseases. Many studies have shown that cellular senescence is related to phosphatase and tension homolog deleted on chromosome ten (PTEN) loss and mammalian target of rapamycin (mTOR) activation. Although it has been reported that mTOR complex 1 (mTORC1) is major anti-aging target in several cell types, the functions and mechanisms of mTOR complex 2 (mTORC2) during aging have not been elucidated in vascular smooth muscle cells (VSMCs). Therefore, the aim of this study was to reveal the relationship between PTEN and mTORC2 during VSMC senescence. We found adriamycin-induced VSMC senescence was accompanied by reduced PTEN protein expression and upregulation of the mTORC2-Akt (Ser 473) pathway and that fisetin treatment reduced VSMC senescence by increasing PTEN and decreasing mTORC2 protein levels. Furthermore, PTEN played a primary role in the anti-aging effect of fisetin, and fisetin-activated PTEN directly regulated the mTORC2-Akt (Ser 473) signaling pathway, and attenuated senescence phenotypes such as senescence-associated β-galactosidase (SA-β-gal) and the p53-p21 signaling pathway in VSMCs. In mouse aortas, fisetin delayed aging by regulating the PTEN-mTORC2-Akt (Ser473) signaling pathway. These results suggest PTEN and mTORC2 are associated with cellular senescence in VSMCs and that the mTORC2-Akt (Ser 473) signaling pathway be considered a new target for preventing senescence-related diseases.
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Affiliation(s)
- Seul Gi Kim
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea; Smart-aging Convergence Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea
| | - Jin Young Sung
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea; Smart-aging Convergence Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea
| | - Jae-Ryong Kim
- Department of Biochemistry and Molecular Biology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea; Smart-aging Convergence Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea
| | - Hyoung Chul Choi
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea; Smart-aging Convergence Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu 42415, Republic of Korea.
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Hur J, Kang ES, Hwang JS, Lee WJ, Won JP, Lee HG, Kim E, Seo HG. Peroxisome proliferator-activated receptor-δ-mediated upregulation of catalase helps to reduce ultraviolet B-induced cellular injury in dermal fibroblasts. J Dermatol Sci 2021; 103:167-175. [PMID: 34420848 DOI: 10.1016/j.jdermsci.2021.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 07/20/2021] [Accepted: 08/10/2021] [Indexed: 12/31/2022]
Abstract
BACKGROUND Previous studies suggested that the nuclear receptor peroxisome proliferator-activated receptor (PPAR)-δ plays an essential role in cellular responses against oxidative stress. OBJECTIVE To investigate how PPAR-δ elicits cellular responses against oxidative stress in primary human dermal fibroblasts (HDFs) exposed to ultraviolet B (UVB). METHODS The present study was undertaken in HDFs by performing real-time polymerase chain reaction, gene silencing, cytotoxicity and reporter gene assay, analyses for catalase and reactive oxygen species, and immunoblot analyses. RESULTS The PPAR-δ activator GW501516 upregulated expression of catalase and this upregulation was attenuated by PPAR-δ-targeting siRNA. GW501516-activated PPAR-δ induced catalase promoter activity through a direct repeat 1 response element. Mutation of this response element completely abrogated transcriptional activation, indicating that this site is a novel type of PPAR-δ response element. In addition, GW501516-activated PPAR-δ counteracted the reductions in activity and expression of catalase induced by UVB irradiation. These recovery effects were significantly attenuated in the presence of PPAR-δ-targeting siRNA or the specific PPAR-δ antagonist GSK0660. GW501516-activated PPAR-δ also protected HDFs from cellular damage triggered by UVB irradiation, and this PPAR-δ-mediated reduction of cellular damage was reversed by the catalase inhibitor or catalase-targeting siRNA. These effects of catalase blockade were positively correlated with accumulation of reactive oxygen species in HDFs exposed to UVB. Furthermore, GW501516-activated PPAR-δ targeted peroxisomal hydrogen peroxide through catalase in UVB-irradiated HDFs. CONCLUSION The gene encoding catalase is a target of PPAR-δ, and this novel catalase-mediated pathway plays a critical role in the cellular response elicited by PPAR-δ against oxidative stress.
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Affiliation(s)
- Jinwoo Hur
- College of Sang-Huh Life Science, Konkuk University, Seoul, Republic of Korea
| | - Eun Sil Kang
- College of Sang-Huh Life Science, Konkuk University, Seoul, Republic of Korea
| | - Jung Seok Hwang
- College of Sang-Huh Life Science, Konkuk University, Seoul, Republic of Korea
| | - Won Jin Lee
- College of Sang-Huh Life Science, Konkuk University, Seoul, Republic of Korea
| | - Jun Pil Won
- College of Sang-Huh Life Science, Konkuk University, Seoul, Republic of Korea
| | - Hyuk Gyoon Lee
- College of Sang-Huh Life Science, Konkuk University, Seoul, Republic of Korea
| | - Eunsu Kim
- College of Sang-Huh Life Science, Konkuk University, Seoul, Republic of Korea
| | - Han Geuk Seo
- College of Sang-Huh Life Science, Konkuk University, Seoul, Republic of Korea.
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Hwang JS, Hur J, Lee WJ, Won JP, Lee HG, Lim DS, Kim E, Seo HG. Catalase Mediates the Inhibitory Actions of PPARδ against Angiotensin II-Triggered Hypertrophy in H9c2 Cardiomyocytes. Antioxidants (Basel) 2021; 10:antiox10081223. [PMID: 34439471 PMCID: PMC8388952 DOI: 10.3390/antiox10081223] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 01/05/2023] Open
Abstract
Hypertrophy of myocytes has been implicated in cardiac dysfunctions affecting wall stress and patterns of gene expression. However, molecular targets potentially preventing cardiac hypertrophy have not been fully elucidated. In the present study, we demonstrate that upregulation of catalase by peroxisome proliferator-activated receptor δ (PPARδ) is involved in the anti-hypertrophic activity of PPARδ in angiotensin II (Ang II)-treated H9c2 cardiomyocytes. Activation of PPARδ by a specific ligand GW501516 significantly inhibited Ang II-induced hypertrophy and the generation of reactive oxygen species (ROS) in H9c2 cardiomyocytes. These effects of GW501516 were almost completely abolished in cells stably expressing small hairpin (sh)RNA targeting PPARδ, indicating that PPARδ mediates these effects. Significant concentration and time-dependent increases in catalase at both mRNA and protein levels were observed in GW501516-treated H9c2 cardiomyocytes. In addition, GW501516-activated PPARδ significantly enhanced catalase promoter activity and protein expression, even in the presence of Ang II. GW501516-activated PPARδ also inhibited the expression of atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP), which are both marker proteins for hypertrophy. The effects of GW501516 on the expression of ANP and BNP were reversed by 3-amino-1,2,4-triazole (3-AT), a catalase inhibitor. Inhibition or downregulation of catalase by 3-AT or small interfering (si)RNA, respectively, abrogated the effects of PPARδ on Ang II-induced hypertrophy and ROS generation, indicating that these effects of PPARδ are mediated through catalase induction. Furthermore, GW501516-activated PPARδ exerted catalase-dependent inhibitory effects on Ang II-induced hypertrophy by blocking p38 mitogen-activated protein kinase. Taken together, these results indicate that the anti-hypertrophic activity of PPARδ may be achieved, at least in part, by sequestering ROS through fine-tuning the expression of catalase in cardiomyocytes.
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Affiliation(s)
- Jung Seok Hwang
- College of Sang-Huh Life Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea; (J.S.H.); (J.H.); (W.J.L.); (J.P.W.); (H.G.L.); (E.K.)
| | - Jinwoo Hur
- College of Sang-Huh Life Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea; (J.S.H.); (J.H.); (W.J.L.); (J.P.W.); (H.G.L.); (E.K.)
| | - Won Jin Lee
- College of Sang-Huh Life Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea; (J.S.H.); (J.H.); (W.J.L.); (J.P.W.); (H.G.L.); (E.K.)
| | - Jun Pil Won
- College of Sang-Huh Life Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea; (J.S.H.); (J.H.); (W.J.L.); (J.P.W.); (H.G.L.); (E.K.)
| | - Hyuk Gyoon Lee
- College of Sang-Huh Life Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea; (J.S.H.); (J.H.); (W.J.L.); (J.P.W.); (H.G.L.); (E.K.)
| | - Dae-Seog Lim
- Department of Biotechnology, CHA University, 355 Pangyo-ro, Bundang-gu, Seongnam 13488, Korea;
| | - Eunsu Kim
- College of Sang-Huh Life Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea; (J.S.H.); (J.H.); (W.J.L.); (J.P.W.); (H.G.L.); (E.K.)
| | - Han Geuk Seo
- College of Sang-Huh Life Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea; (J.S.H.); (J.H.); (W.J.L.); (J.P.W.); (H.G.L.); (E.K.)
- Correspondence: ; Tel.: +82-2-450-0428; Fax: +82-2-455-1044
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Wagner N, Wagner KD. PPAR Beta/Delta and the Hallmarks of Cancer. Cells 2020; 9:cells9051133. [PMID: 32375405 PMCID: PMC7291220 DOI: 10.3390/cells9051133] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 12/17/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor family. Three different isoforms, PPAR alpha, PPAR beta/delta and PPAR gamma have been identified. They all form heterodimers with retinoic X receptors to activate or repress downstream target genes dependent on the presence/absence of ligands and coactivators or corepressors. PPARs differ in their tissue expression profile, ligands and specific agonists and antagonists. PPARs attract attention as potential therapeutic targets for a variety of diseases. PPAR alpha and gamma agonists are in clinical use for the treatment of dyslipidemias and diabetes. For both receptors, several clinical trials as potential therapeutic targets for cancer are ongoing. In contrast, PPAR beta/delta has been suggested as a therapeutic target for metabolic syndrome. However, potential risks in the settings of cancer are less clear. A variety of studies have investigated PPAR beta/delta expression or activation/inhibition in different cancer cell models in vitro, but the relevance for cancer growth in vivo is less well documented and controversial. In this review, we summarize critically the knowledge of PPAR beta/delta functions for the different hallmarks of cancer biological capabilities, which interplay to determine cancer growth.
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Kang ES, Kim HJ, Han SG, Seo HG. Duck Oil-loaded Nanoemulsion Inhibits Senescence of Angiotensin II-treated Vascular Smooth Muscle Cells by Upregulating SIRT1. Food Sci Anim Resour 2020; 40:106-117. [PMID: 31970335 PMCID: PMC6957441 DOI: 10.5851/kosfa.2019.e93] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 10/14/2019] [Accepted: 12/02/2019] [Indexed: 01/11/2023] Open
Abstract
Cellular senescence is associated with age-related vascular disorders and has
been implicated in vascular dysfunctions. Here, we show that duck oil-loaded
nanoemulsion (DO-NE) attenuates premature senescence of vascular smooth muscle
cells (VSMCs) triggered by angiotensin II (Ang II). Compared with control
nanoemulsion (NE), DO-NE significantly inhibited the activity of
senescence-associated β-galactosidase, which is a biomarker of cellular
senescence, in Ang II-treated VSMCs. SIRT1 protein expression was dose- and
time-dependently induced in VSMCs exposed to DO-NE, but not in those exposed to
NE, and SIRT1 promoter activity was also elevated. Consistently, DO-NE also
dose-dependently rescued Ang II-induced repression of SIRT1 expression,
indicating that SIRT1 is linked to the anti-senescence action of DO-NE in VSMCs
treated with Ang II. Furthermore, the SIRT1 agonist resveratrol potentiated the
effects of DO-NE on VSMCs exposed to Ang II, whereas the SIRT1 inhibitor
sirtinol elicited the opposite effect. These findings indicate that DO-NE
inhibits senescence by upregulating SIRT1 and thereby impedes vascular aging
triggered by Ang II.
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Affiliation(s)
- Eun Sil Kang
- Department of Food Science and Biotechnology of Animal Resources, College of Sang-Huh Life Science, Konkuk University, Seoul 05029, Korea
| | - Hyo Juong Kim
- Taekyung Food and Processing R&D Center, Seoul 07057, Korea
| | - Sung Gu Han
- Department of Food Science and Biotechnology of Animal Resources, College of Sang-Huh Life Science, Konkuk University, Seoul 05029, Korea
| | - Han Geuk Seo
- Department of Food Science and Biotechnology of Animal Resources, College of Sang-Huh Life Science, Konkuk University, Seoul 05029, Korea
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Peters JM, Kim DJ, Bility MT, Borland MG, Zhu B, Gonzalez FJ. Regulatory mechanisms mediated by peroxisome proliferator-activated receptor-β/δ in skin cancer. Mol Carcinog 2019; 58:1612-1622. [PMID: 31062422 DOI: 10.1002/mc.23033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 04/12/2019] [Accepted: 04/15/2019] [Indexed: 12/21/2022]
Abstract
Considerable progress has been made during the past 20 years towards elucidating the role of peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) in skin cancer. In 1999, the original notion that PPARβ/δ was involved with epithelial cell function was postulated based on a correlation between PPARβ/δ expression and the induction of messenger RNAs encoding proteins that mediate terminal differentiation in keratinocytes. Subsequent studies definitively revealed that PPARβ/δ could induce terminal differentiation and inhibit proliferation of keratinocytes. Molecular mechanisms have since been discovered to explain how this nuclear receptor can be targeted for preventing and treating skin cancer. This includes the regulation of terminal differentiation, mitotic signaling, endoplasmic reticulum stress, and cellular senescence. Interestingly, the effects of activating PPARβ/δ can preferentially target keratinocytes with genetic mutations associated with skin cancer. This review provides the history and current understanding of how PPARβ/δ can be targeted for both nonmelanoma skin cancer and melanoma and postulates how future approaches that modulate PPARβ/δ signaling may be developed for the prevention and treatment of these diseases.
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Affiliation(s)
- Jeffrey M Peters
- Department of Veterinary and Biomedical Sciences, The Center of Molecular Toxicology and Carcinogenesis, The Pennsylvania State University, University Park, Pennsylvania
| | - Dae J Kim
- Department of Molecular Science, School of Medicine, University of Texas Rio Grande Valley, Edinburg, Texas
| | - Moses T Bility
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Michael G Borland
- Department of Chemistry & Biochemistry, Bloomsburg University of Pennsylvania, Bloomsburg, Pennsylvania
| | - Bokai Zhu
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Frank J Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
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Kang ES, Hwang JS, Lee WJ, Lee GH, Choi MJ, Paek KS, Lim DS, Seo HG. Ligand-activated PPARδ inhibits angiotensin II-stimulated hypertrophy of vascular smooth muscle cells by targeting ROS. PLoS One 2019; 14:e0210482. [PMID: 30620754 PMCID: PMC6324793 DOI: 10.1371/journal.pone.0210482] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 12/25/2018] [Indexed: 11/19/2022] Open
Abstract
We investigated the effect of peroxisome proliferator-activated receptor δ (PPARδ) on angiotensin II (Ang II)-triggered hypertrophy of vascular smooth muscle cells (VSMCs). Activation of PPARδ by GW501516, a specific ligand of PPARδ, significantly inhibited Ang II-stimulated protein synthesis in a concentration-dependent manner, as determined by [3H]-leucine incorporation. GW501516-activated PPARδ also suppressed Ang II-induced generation of reactive oxygen species (ROS) in VSMCs. Transfection of small interfering RNA (siRNA) against PPARδ significantly reversed the effects of GW501516 on [3H]-leucine incorporation and ROS generation, indicating that PPARδ is involved in these effects. By contrast, these GW501516-mediated actions were potentiated in VSMCs transfected with siRNA against NADPH oxidase (NOX) 1 or 4, suggesting that ligand-activated PPARδ elicits these effects by modulating NOX-mediated ROS generation. The phosphatidylinositol 3-kinase inhibitor LY294002 also inhibited Ang II-stimulated [3H]-leucine incorporation and ROS generation by preventing membrane translocation of Rac1. These observations suggest that PPARδ is an endogenous modulator of Ang II-triggered hypertrophy of VSMCs, and is thus a potential target to treat vascular diseases associated with hypertrophic changes of VSMCs.
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Affiliation(s)
- Eun Sil Kang
- College of Sang-Huh Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Jung Seok Hwang
- College of Sang-Huh Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Won Jin Lee
- College of Sang-Huh Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Gyeong Hee Lee
- College of Sang-Huh Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Mi-Jung Choi
- College of Sang-Huh Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | | | - Dae-Seog Lim
- Department of Biotechnology, CHA University, Bundang-gu, Seongnam, Korea
| | - Han Geuk Seo
- College of Sang-Huh Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
- * E-mail:
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Cheng KC, Chang WT, Li Y, Cheng YZ, Cheng JT, Chen ZC. GW0742 activates peroxisome proliferator-activated receptor δ to reduce free radicals and alleviate cardiac hypertrophy induced by hyperglycemia in cultured H9c2 cells. J Cell Biochem 2018; 119:9532-9542. [PMID: 30129179 DOI: 10.1002/jcb.27270] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/26/2018] [Indexed: 01/24/2023]
Abstract
Peroxisome proliferator-activated receptor δ (PPARδ), the predominant PPAR subtype in the heart, is known to regulate cardiac function. PPARδ activation may inhibit cardiac hypertrophy in H9c2 cells while the potential mechanism has not been elucidated. Then, H9c2 cells incubated with high glucose to induce hypertrophy were used to investigate using GW0742 to activate PPARδ. The fluorescence assays were applied to determine the changes in cell size, cellular calcium levels, and free radicals. Western blot analyses for hypertrophic signals and assays of messenger RNA (mRNA) levels for hypertrophic biomarkers were performed. In H9c2 cells, GW0742 inhibited cardiac hypertrophy. In addition, increases in cellular calcium and hypertrophic signals, including calcineurin and nuclear factor of activated T-cells, were reduced by GW0742. This reduction was parallel to the decrease in the mRNA levels of biomarkers, such as brain/B-type natriuretic peptides and β-myosin heavy chain. These effects of GW0742 were dose-dependently inhibited by GSK0660 indicating an activation of PPARδ by GW0742 to alleviate cardiac hypertrophy. Moreover, free radicals produced by hyperglycemia were also markedly inhibited by GW0742 and were later reversed by GSK0660. GW0742 promoted the expression of thioredoxin, an antioxidant enzyme. Direct inhibition of reactive oxygen species by GW0742 was also identified in the oxidant potassium bromate stimulated H9c2 cells. Taken together, these findings suggest that PPARδ agonists can inhibit free radicals, resulting in lower cellular calcium for reduction of hypertrophic signaling to alleviate cardiac hypertrophy in H9c2 cells. Therefore, PPARδ activation can be used to develop agent(s) for treating cardiac hypertrophy.
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Affiliation(s)
- Kai-Chun Cheng
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Wei-Ting Chang
- Department of Cardiology, Chi-Mei Medical Center, Tainan, Taiwan
| | - Yingxiao Li
- Department of Psychosomatic Internal Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.,Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan
| | - Yung-Ze Cheng
- Department of Emergency Medicine, Chi-Mei Medical Center, Tainan, Taiwan
| | - Juei-Tang Cheng
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan.,Graduate Institute of Medical Science, Chang Jung Christian University, Gueiren, Tainan, Taiwan
| | - Zhih-Cherng Chen
- Department of Cardiology, Chi-Mei Medical Center, Tainan, Taiwan.,Department of Pharmacy, Chia Nan University of Pharmacy & Science, Tainan, Taiwan
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Ahn MY, Ham SA, Yoo T, Lee WJ, Hwang JS, Paek KS, Lim DS, Han SG, Lee CH, Seo HG. Ligand-Activated Peroxisome Proliferator-Activated Receptor δ Attenuates Vascular Oxidative Stress by Inhibiting Thrombospondin-1 Expression. J Vasc Res 2018; 55:75-86. [PMID: 29408825 DOI: 10.1159/000486570] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 12/29/2017] [Indexed: 11/19/2022] Open
Abstract
Thrombospondin-1 (TSP-1) is implicated in vascular diseases associated with oxidative stress, such as abdominal aortic aneurysms, ischemia-reperfusion injury, and atherosclerosis. However, the regulatory mechanisms underlying TSP-1 expression are not fully elucidated. In this study, we found that peroxisome proliferator-activated receptor δ (PPARδ) inhibited oxidative stress-induced TSP-1 expression and migration in vascular smooth muscle cells (VSMCs). Activation of PPARδ by GW501516, a specific ligand for PPARδ, significantly attenuated hydrogen peroxide (H2O2)-induced expression of TSP-1 in VSMCs. Small interfering RNA-mediated knockdown of PPARδ and treatment with GSK0660, a selective PPARδ antagonist, reversed the effect of GW501516 on H2O2-induced expression of TSP-1, suggesting that PPARδ is associated with GW501516 activity. Furthermore, JNK (c-Jun N-terminal kinase), but not p38 and ERK (extracellular signal-regulated kinase), mediated PPARδ-dependent inhibition of TSP-1 expression in VSMCs exposed to H2O2. GW501516- activated PPARδ also reduced the H2O2-induced generation of reactive oxygen species, concomitant with inhibition of VSMC migration. In particular, TSP-1 contributed to the action of PPARδ in the regulation of H2O2-induced interleukin-1β expression. These results suggest that PPARδ-modulated downregulation of TSP-1 is associated with reduced cellular oxidative stress, thereby inhibiting H2O2-induced pheno-typic changes in vascular cells.
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Affiliation(s)
- Min Young Ahn
- Sanghuh College of Life Sciences, Konkuk University, Seoul, Republic of Korea
| | - Sun Ah Ham
- Sanghuh College of Life Sciences, Konkuk University, Seoul, Republic of Korea
| | - Taesik Yoo
- Sanghuh College of Life Sciences, Konkuk University, Seoul, Republic of Korea
| | - Won Jin Lee
- Sanghuh College of Life Sciences, Konkuk University, Seoul, Republic of Korea
| | - Jung Seok Hwang
- Sanghuh College of Life Sciences, Konkuk University, Seoul, Republic of Korea
| | - Kyung Shin Paek
- Department of Nursing, Semyung University, Jechon, Republic of Korea
| | - Dae-Seog Lim
- Department of Biotechnology, CHA University, Seongnam, Republic of Korea
| | - Sung Gu Han
- Sanghuh College of Life Sciences, Konkuk University, Seoul, Republic of Korea
| | - Chi-Ho Lee
- Sanghuh College of Life Sciences, Konkuk University, Seoul, Republic of Korea
| | - Han Geuk Seo
- Sanghuh College of Life Sciences, Konkuk University, Seoul, Republic of Korea
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13
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Tan EHP, Sng MK, How ISB, Chan JSK, Chen J, Tan CK, Wahli W, Tan NS. ROS release by PPARβ/δ-null fibroblasts reduces tumor load through epithelial antioxidant response. Oncogene 2018; 37:2067-2078. [PMID: 29367760 PMCID: PMC5895604 DOI: 10.1038/s41388-017-0109-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 11/06/2017] [Accepted: 12/14/2017] [Indexed: 12/26/2022]
Abstract
Tumor stroma has an active role in the initiation, growth, and propagation of many tumor types by secreting growth factors and modulating redox status of the microenvironment. Although PPARβ/δ in fibroblasts was shown to modulate oxidative stress in the wound microenvironment, there has been no evidence of a similar effect in the tumor stroma. Here, we present evidence of oxidative stress modulation by intestinal stromal PPARβ/δ, using a FSPCre-Pparb/d−/− mouse model and validated it with immortalized cell lines. The FSPCre-Pparb/d−/− mice developed fewer intestinal polyps and survived longer when compared with Pparb/dfl/fl mice. The pre-treatment of FSPCre-Pparb/d−/− and Pparb/dfl/fl with antioxidant N-acetyl-cysteine prior DSS-induced tumorigenesis resulted in lower tumor load. Gene expression analyses implicated an altered oxidative stress processes. Indeed, the FSPCre-Pparb/d−/− intestinal tumors have reduced oxidative stress than Pparb/dfl/fl tumors. Similarly, the colorectal cancer cells and human colon epithelial cells also experienced lower oxidative stress when co-cultured with fibroblasts depleted of PPARβ/δ expression. Therefore, our results establish a role for fibroblast PPARβ/δ in epithelial–mesenchymal communication for ROS homeostasis.
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Affiliation(s)
- Eddie Han Pin Tan
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
| | - Ming Keat Sng
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, Singapore, Singapore
| | - Ivan Shun Bo How
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Jeremy Soon Kiat Chan
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Jiapeng Chen
- Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, Singapore, Singapore
| | - Chek Kun Tan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, Singapore, Singapore
| | - Walter Wahli
- Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, Singapore, Singapore.,INRA ToxAlim, UMR1331, Chemin de Tournefeuille, Toulouse Cedex 3, France.,Center for Integrative Genomics, University of Lausanne, Le Genopode, Lausanne, Switzerland
| | - Nguan Soon Tan
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore. .,Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, Singapore, Singapore. .,Institute of Molecular and Cell Biology, Proteos, Agency for Science Technology & Research, Singapore, Singapore. .,KK Research Centre, KK Women's and Children Hospital, Singapore, Singapore.
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14
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Effect of Phosphatase and Tensin Homologue on Chromosome 10 on Angiotensin II-Mediated Proliferation, Collagen Synthesis, and Akt/P27 Signaling in Neonatal Rat Cardiac Fibroblasts. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2860516. [PMID: 27747225 PMCID: PMC5055941 DOI: 10.1155/2016/2860516] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 06/05/2016] [Indexed: 11/17/2022]
Abstract
Cardiac fibroblasts (CFs) play a key role in cardiac fibrosis by regulating the balance between extracellular matrix synthesis and breakdown. Although phosphatase and tensin homologue on chromosome 10 (PTEN) has been found to play an important role in cardiovascular disease, it is not clear whether PTEN is involved in functional regulation of CFs. In the present study, PTEN was overexpressed in neonatal rat CFs via recombinant adenovirus-mediated gene transfer. The effects of PTEN overexpression on cell-cycle progression and angiotensin II- (Ang II-) mediated regulation of collagen metabolism, synthesis of matrix metalloproteinases, and Akt/P27 signaling were investigated. Compared with uninfected cells and cells infected with green fluorescent protein-expressing adenovirus (Ad-GFP), cells infected with PTEN-expressing adenovirus (Ad-PTEN) significantly increased PTEN protein and mRNA levels in CFs (P < 0.05). The proportion of CFs in the G1/S cell-cycle phase was significantly higher for PTEN-overexpressing cells. In addition, Ad-PTEN decreased mRNA expression and the protein synthesis rate of collagen types I and III and antagonized Ang II-induced collagen synthesis. Overexpression of PTEN also decreased Ang II-induced matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1) production as well as gelatinase activity. Moreover, Ad-PTEN decreased Akt expression and increased P27 expression independent of Ang II stimulation. These results suggest that PTEN could regulate its functional effects in neonatal rat CFs partially via the Akt/P27 signaling pathway.
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15
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Chronic peroxisome proliferator-activated receptorβ/δ agonist GW0742 prevents hypertension, vascular inflammatory and oxidative status, and endothelial dysfunction in diet-induced obesity. J Hypertens 2016; 33:1831-44. [PMID: 26147382 DOI: 10.1097/hjh.0000000000000634] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Endothelial dysfunction plays a key role in obesity-induced risk of cardiovascular disease. The aim of the present study was to analyze the effect of chronic peroxisome proliferator-activated receptor (PPAR)β/δ agonist GW0742 treatment on endothelial function in obese mice fed a high-fat diet (HFD). METHODS AND RESULTS Five-week-old male mice were allocated to one of the following groups: control, control-treated (GW0742, 3 mg/kg per day, by oral gavage), HFD, HFD + GW0742, HFD + GSK0660 (1 mg/kg/day, intraperitoneal) or HFD-GW0742-GSK0660 and followed for 11 or 13 weeks. GW0742 administration to mice fed HFD prevented the gain of body weight, heart and kidney hypertrophy, and fat accumulation. The increase in plasma levels of fasting glucose, glucose tolerance test, homeostatic model assessment of insulin resistance, and triglyceride found in the HFD group was suppressed by GW0742. This agonist increased plasma HDL in HFD-fed mice and restored the levels of tumor necrosis factor-α and adiponectin in fat. GW0742 prevented the impaired nitric oxide-dependent vasodilatation induced by acetylcholine in aortic rings from mice fed HFD. Moreover, GW0742 increased both aortic Akt and endothelial nitric oxide synthase phosphorylation, and inhibited the increase in caveolin-1/endothelial nitric oxide synthase interaction, ethidium fluorescence, NOX-1, Toll-like receptor 4, tumor necrosis factor-α, and interleukin-6 expression, and IκBα phosphorylation found in aortae from the HFD group. GSK0660 prevented all changes induced by GW0742. CONCLUSION PPARβ/δ activation prevents obesity and exerts protective effects on hypertension and on the early manifestations of atherosclerosis, that is, endothelial dysfunction and the vascular pro-oxidant and pro-inflammatory status, in HFD-fed mice.
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16
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Delaney C, Wright RH, Tang JR, Woods C, Villegas L, Sherlock L, Savani RC, Abman SH, Nozik-Grayck E. Lack of EC-SOD worsens alveolar and vascular development in a neonatal mouse model of bleomycin-induced bronchopulmonary dysplasia and pulmonary hypertension. Pediatr Res 2015; 78:634-40. [PMID: 26322414 PMCID: PMC4689645 DOI: 10.1038/pr.2015.166] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 06/08/2015] [Indexed: 01/28/2023]
Abstract
BACKGROUND Pulmonary hypertension (PH) worsens clinical outcomes in former preterm infants with bronchopulmonary dysplasia (BPD). Oxidant stress disrupts alveolar and vascular development in models of BPD. Bleomycin causes oxidative stress and induces BPD and PAH in neonatal rats. Disruption in the vascular endothelial growth factor (VEGF) and nitric oxide signaling pathways contributes to BPD. We hypothesized that loss of EC-SOD would worsen PAH associated with BPD in a neonatal mouse model of bleomycin-induced BPD by disrupting the VEGF/NO signaling pathway. METHODS Neonatal wild-type mice (WT), and mice lacking EC-SOD (EC-SOD KO) received intraperitoneal bleomycin (2 units/kg) or phosphate-buffered saline (PBS) three times weekly and were evaluated at weeks 3 or 4. RESULTS Lack of EC-SOD impaired alveolar development and resulted in PH (elevated right ventricular systolic pressures, right ventricular hypertrophy (RVH)), decreased vessel density, and increased small vessel muscularization. Exposure to bleomycin further impaired alveolar development, worsened RVH and vascular remodeling. Lack of EC-SOD and bleomycin treatment decreased lung total and phosphorylated VEGFR2 and eNOS protein expression. CONCLUSION EC-SOD is critical in preserving normal lung development and loss of EC-SOD results in disrupted alveolar development, PAH and vascular remodeling at baseline, which is further worsened with bleomycin and associated with decreased activation of VEGFR2.
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Affiliation(s)
- Cassidy Delaney
- Department of Pediatrics, University of Colorado School of Medicine and Children’s Hospital Colorado, Aurora, CO United States,Corresponding Author: Cassidy Delaney, MD, 13121 E 17th Ave B8402, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, , Office: 303-724-0759, Fax: 303-724-7323
| | - Rachel H. Wright
- Department of Pediatrics, University of Colorado School of Medicine and Children’s Hospital Colorado, Aurora, CO United States
| | - Jen-Ruey Tang
- Department of Pediatrics, University of Colorado School of Medicine and Children’s Hospital Colorado, Aurora, CO United States
| | - Crystal Woods
- Department of Pediatrics, University of Colorado School of Medicine and Children’s Hospital Colorado, Aurora, CO United States
| | - Leah Villegas
- Department of Pediatrics, University of Colorado School of Medicine and Children’s Hospital Colorado, Aurora, CO United States
| | - Laurie Sherlock
- Department of Pediatrics, University of Colorado School of Medicine and Children’s Hospital Colorado, Aurora, CO United States
| | - Rashmin C. Savani
- Department of Pediatrics, University of Texas Southwestern Medical Center at Dallas, Dallas, TX United States
| | - Steven H. Abman
- Department of Pediatrics, University of Colorado School of Medicine and Children’s Hospital Colorado, Aurora, CO United States
| | - Eva Nozik-Grayck
- Department of Pediatrics, University of Colorado School of Medicine and Children’s Hospital Colorado, Aurora, CO United States
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17
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Gene Signature of Human Oral Mucosa Fibroblasts: Comparison with Dermal Fibroblasts and Induced Pluripotent Stem Cells. BIOMED RESEARCH INTERNATIONAL 2015; 2015:121575. [PMID: 26339586 PMCID: PMC4538314 DOI: 10.1155/2015/121575] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 04/03/2015] [Accepted: 04/10/2015] [Indexed: 01/27/2023]
Abstract
Oral mucosa is a useful material for regeneration therapy with the advantages of its accessibility and versatility regardless of age and gender. However, little is known about the molecular characteristics of oral mucosa. Here we report the first comparative profiles of the gene signatures of human oral mucosa fibroblasts (hOFs), human dermal fibroblasts (hDFs), and hOF-derived induced pluripotent stem cells (hOF-iPSCs), linking these with biological roles by functional annotation and pathway analyses. As a common feature of fibroblasts, both hOFs and hDFs expressed glycolipid metabolism-related genes at higher levels compared with hOF-iPSCs. Distinct characteristics of hOFs compared with hDFs included a high expression of glycoprotein genes, involved in signaling, extracellular matrix, membrane, and receptor proteins, besides a low expression of HOX genes, the hDFs-markers. The results of the pathway analyses indicated that tissue-reconstructive, proliferative, and signaling pathways are active, whereas senescence-related genes in p53 pathway are inactive in hOFs. Furthermore, more than half of hOF-specific genes were similarly expressed to those of hOF-iPSC genes and might be controlled by WNT signaling. Our findings demonstrated that hOFs have unique cellular characteristics in specificity and plasticity. These data may provide useful insight into application of oral fibroblasts for direct reprograming.
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18
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Abstract
The role of peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) in cancer remains contentious due in large part to divergent publications indicating opposing effects in different rodent and human cell culture models. During the past 10 years, some facts regarding PPARβ/δ in cancer have become clearer, while others remain uncertain. For example, it is now well accepted that (1) expression of PPARβ/δ is relatively lower in most human tumors as compared to the corresponding non-transformed tissue, (2) PPARβ/δ promotes terminal differentiation, and (3) PPARβ/δ inhibits pro-inflammatory signaling in multiple in vivo models. However, whether PPARβ/δ is suitable to target with natural and/or synthetic agonists or antagonists for cancer chemoprevention is hindered because of the uncertainty in the mechanism of action and role in carcinogenesis. Recent findings that shed new insight into the possibility of targeting this nuclear receptor to improve human health will be discussed.
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19
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Hwang JS, Eun SY, Ham SA, Yoo T, Lee WJ, Paek KS, Do JT, Lim DS, Seo HG. PPARδ modulates oxLDL-induced apoptosis of vascular smooth muscle cells through a TGF-β/FAK signaling axis. Int J Biochem Cell Biol 2015; 62:54-61. [PMID: 25732738 DOI: 10.1016/j.biocel.2015.02.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 02/17/2015] [Accepted: 02/20/2015] [Indexed: 12/24/2022]
Abstract
The peroxisome proliferator-activated receptor delta (PPARδ) has been implicated in the modulation of vascular homeostasis. However, its roles in the apoptotic cell death of vascular smooth muscle cells (VSMCs) are poorly understood. Here, we demonstrate that PPARδ modulates oxidized low-density lipoprotein (oxLDL)-induced apoptosis of VSMCs through the transforming growth factor-β (TGF-β) and focal adhesion kinase (FAK) signaling pathways. Activation of PPARδ by GW501516, which is a specific ligand, significantly inhibited oxLDL-induced cell death and generation of reactive oxygen species in VSMCs. These inhibitory effects were significantly reversed in the presence of small interfering (si)RNA against PPARδ, or by blockade of the TGF-β or FAK signaling pathways. Furthermore, PPARδ-mediated recovery of FAK phosphorylation suppressed by oxLDL was reversed by SB431542, a specific ALK5 receptor inhibitor, indicating that a TGF-β/FAK signaling axis is involved in the action of PPARδ. Among the protein kinases activated by oxLDL, p38 mitogen-activated protein kinase was suppressed by ligand-activated PPARδ. In addition, oxLDL-induced expression and translocation of pro-apoptotic or anti-apoptotic factors were markedly affected in the presence of GW501516. Those effects were reversed by PPARδ siRNA, or inhibitors of TGF-β or FAK, which also suggests that PPARδ exerts its anti-apoptotic effect via a TGF-β/FAK signaling axis. Taken together, these findings indicate that PPARδ plays an important role in the pathophysiology of disease associated with apoptosis of VSMC, such as atherosclerosis and restanosis.
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Affiliation(s)
- Jung Seok Hwang
- Department of Animal Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - So Young Eun
- Department of Animal Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - Sun Ah Ham
- Department of Animal Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - Taesik Yoo
- Department of Animal Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - Won Jin Lee
- Department of Animal Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - Kyung Shin Paek
- Department of Nursing, Semyung University, 65 Semyung-ro, Jecheon, Chungbuk 390-711, Republic of Korea
| | - Jeong Tae Do
- Department of Animal Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - Dae-Seog Lim
- Department of Applied Bioscience, CHA University, 355 Pangyo-ro, Bundang-gu, Seongnam, Gyeonggi-do 463-400, Republic of Korea
| | - Han Geuk Seo
- Department of Animal Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-Gu, Seoul 143-701, Republic of Korea.
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20
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Ham SA, Hwang JS, Kang ES, Yoo T, Lim HH, Lee WJ, Paek KS, Seo HG. Ethanol extract of Dalbergia odorifera protects skin keratinocytes against ultraviolet B-induced photoaging by suppressing production of reactive oxygen species. Biosci Biotechnol Biochem 2015; 79:760-6. [PMID: 25560618 DOI: 10.1080/09168451.2014.993916] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Dalbergia odorifera T. Chen (Leguminosae), an indigenous medicinal herb, has been widely used in northern and eastern Asia to treat diverse diseases. Here, we investigated the anti-senescent effects of ethanolic extracts of Dalbergia odorifera (EEDO) in ultraviolet (UV) B-irradiated skin cells. EEDO significantly inhibited UVB-induced senescence of human keratinocytes in a concentration-dependent manner, concomitant with inhibition of reactive oxygen species (ROS) generation. UVB-induced increases in the levels of p53 and p21, biomarkers of cellular senescence, were almost completely abolished in the presence of EEDO. Sativanone, a major constituent of EEDO, also attenuated UVB-induced senescence and ROS generation in keratinocytes, indicating that sativanone is an indexing (marker) molecule for the anti-senescence properties of EEDO. Finally, treatment of EEDO to mice exposed to UVB significantly reduced ROS levels and the number of senescent cells in the skin. Thus, EEDO confers resistance to UVB-induced cellular senescence by inhibiting ROS generation in skin cells.
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Affiliation(s)
- Sun Ah Ham
- a Department of Animal Biotechnology , Konkuk University , Seoul , Republic of Korea
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21
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Stanley C, O'Sullivan SE. Vascular targets for cannabinoids: animal and human studies. Br J Pharmacol 2014; 171:1361-78. [PMID: 24329566 DOI: 10.1111/bph.12560] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 10/18/2013] [Accepted: 11/18/2013] [Indexed: 12/19/2022] Open
Abstract
UNLABELLED Application of cannabinoids and endocannabinoids to perfused vascular beds or individual isolated arteries results in changes in vascular resistance. In most cases, the result is vasorelaxation, although vasoconstrictor responses are also observed. Cannabinoids also modulate the actions of vasoactive compounds including acetylcholine, methoxamine, angiotensin II and U46619 (thromboxane mimetic). Numerous mechanisms of action have been proposed including receptor activation, potassium channel activation, calcium channel inhibition and the production of vasoactive mediators such as calcitonin gene-related peptide, prostanoids, NO, endothelial-derived hyperpolarizing factor and hydrogen peroxide. The purpose of this review is to examine the evidence for the range of receptors now known to be activated by cannabinoids. Direct activation by cannabinoids of CB1 , CBe , TRPV1 (and potentially other TRP channels) and PPARs in the vasculature has been observed. A potential role for CB2, GPR55 and 5-HT1 A has also been identified in some studies. Indirectly, activation of prostanoid receptors (TP, IP, EP1 and EP4 ) and the CGRP receptor is involved in the vascular responses to cannabinoids. The majority of this evidence has been obtained through animal research, but recent work has confirmed some of these targets in human arteries. Vascular responses to cannabinoids are enhanced in hypertension and cirrhosis, but are reduced in obesity and diabetes, both due to changes in the target sites of action. Much further work is required to establish the extent of vascular actions of cannabinoids and the application of this research in physiological and pathophysiological situations. LINKED ARTICLES This article is part of a themed section on Cannabinoids 2013. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-6.
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Affiliation(s)
- Christopher Stanley
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, UK
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22
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Hwang ES. Senescence suppressors: their practical importance in replicative lifespan extension in stem cells. Cell Mol Life Sci 2014; 71:4207-19. [PMID: 25052377 PMCID: PMC11113678 DOI: 10.1007/s00018-014-1685-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 06/23/2014] [Accepted: 07/14/2014] [Indexed: 02/06/2023]
Abstract
Recent animal and clinical studies report promising results for the therapeutic utilization of stem cells in regenerative medicine. Mesenchymal stem cells (MSCs), with their pluripotent nature, have advantages over embryonic stem cells in terms of their availability and feasibility. However, their proliferative activity is destined to slow by replicative senescence, and the limited proliferative potential of MSCs not only hinders the preparation of sufficient cells for in vivo application, but also draws a limitation on their potential for differentiation. This calls for the development of safe and efficient means to increase the proliferative as well as differentiation potential of MSCs. Recent advances have led to a better understanding of the underlying mechanisms and significance of cellular senescence, facilitating ways to manipulate the replicative lifespan of a variety of primary cells, including MSCs. This paper introduces a class of proteins that function as senescence suppressors. Like tumor suppressors, these proteins are lost in senescence, while their forced expression delays the onset of senescence. Moreover, treatments that increase the expression or the activity of senescence suppressors, therefore, cause expansion of the replicative and differentiation potential of MSCs. The nature of the activities and putative underlying mechanisms of the senescence suppressors will be discussed to facilitate their evaluation.
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Affiliation(s)
- Eun Seong Hwang
- Department of Life Science, University of Seoul, Dongdaemungu, Jeonnongdong 90, Seoul, 130-743, Republic of Korea,
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23
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Lehman AMB, Montford JR, Horita H, Ostriker AC, Weiser-Evans MCM, Nemenoff RA, Furgeson SB. Activation of the retinoid X receptor modulates angiotensin II-induced smooth muscle gene expression and inflammation in vascular smooth muscle cells. Mol Pharmacol 2014; 86:570-9. [PMID: 25169989 PMCID: PMC4201143 DOI: 10.1124/mol.114.092163] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 08/28/2014] [Indexed: 01/04/2023] Open
Abstract
The retinoid X receptor (RXR) partners with numerous nuclear receptors, such as the peroxisome proliferator activated receptor (PPAR) family, liver X receptors (LXRs), and farnesoid X receptor (FXR). Although each heterodimer can be activated by specific ligands, a subset of these receptors, defined as permissive nuclear receptors, can also be activated by RXR agonists known as rexinoids. Many individual RXR heterodimers have beneficial effects in vascular smooth muscle cells (SMCs). Because rexinoids can potently activate multiple RXR pathways, we hypothesized that treating SMCs with rexinoids would more effectively reverse the pathophysiologic effects of angiotensin II than an individual heterodimer agonist. Cultured rat aortic SMCs were pretreated with either an RXR agonist (bexarotene or 9-cis retinoic acid) or vehicle (dimethylsulfoxide) for 24 hours before stimulation with angiotensin II. Compared with dimethylsulfoxide, bexarotene blocked angiotensin II-induced SM contractile gene induction (calponin and smooth muscle-α-actin) and protein synthesis ([(3)H]leucine incorporation). Bexarotene also decreased angiotensin II-mediated inflammation, as measured by decreased expression of monocyte chemoattractant protein-1 (MCP-1). Activation of p38 mitogen-activated protein (MAP) kinase but not extracellular signal-related kinase (ERK) or protein kinase B (Akt) was also blunted by bexarotene. We compared bexarotene to five agonists of nuclear receptors (PPARα, PPARγ, PPARδ, LXR, and FXR). Bexarotene had a greater effect on calponin reduction, MCP-1 inhibition, and p38 MAP kinase inhibition than any individual agonist. PPARγ knockout cells demonstrated blunted responses to bexarotene, indicating that PPARγ is necessary for the effects of bexarotene. These data demonstrate that RXR is a potent modulator of angiotensin II-mediated responses in the vasculature, partially through inhibition of p38.
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Affiliation(s)
- Allison M B Lehman
- Division of Renal Diseases and Hypertension (A.L., J.R.M., H.H., A.C.O., M.W.E., R.A.N., S.B.F.), Cardiovascular Pulmonary Research Laboratory, Department of Medicine (M.W.E., R.A.N.), University of Colorado Anschutz Medical Campus, Aurora, Colorado; and Department of Medicine, Denver Health Hospital, Denver, Colorado (S.B.F)
| | - John R Montford
- Division of Renal Diseases and Hypertension (A.L., J.R.M., H.H., A.C.O., M.W.E., R.A.N., S.B.F.), Cardiovascular Pulmonary Research Laboratory, Department of Medicine (M.W.E., R.A.N.), University of Colorado Anschutz Medical Campus, Aurora, Colorado; and Department of Medicine, Denver Health Hospital, Denver, Colorado (S.B.F)
| | - Henrick Horita
- Division of Renal Diseases and Hypertension (A.L., J.R.M., H.H., A.C.O., M.W.E., R.A.N., S.B.F.), Cardiovascular Pulmonary Research Laboratory, Department of Medicine (M.W.E., R.A.N.), University of Colorado Anschutz Medical Campus, Aurora, Colorado; and Department of Medicine, Denver Health Hospital, Denver, Colorado (S.B.F)
| | - Allison C Ostriker
- Division of Renal Diseases and Hypertension (A.L., J.R.M., H.H., A.C.O., M.W.E., R.A.N., S.B.F.), Cardiovascular Pulmonary Research Laboratory, Department of Medicine (M.W.E., R.A.N.), University of Colorado Anschutz Medical Campus, Aurora, Colorado; and Department of Medicine, Denver Health Hospital, Denver, Colorado (S.B.F)
| | - Mary C M Weiser-Evans
- Division of Renal Diseases and Hypertension (A.L., J.R.M., H.H., A.C.O., M.W.E., R.A.N., S.B.F.), Cardiovascular Pulmonary Research Laboratory, Department of Medicine (M.W.E., R.A.N.), University of Colorado Anschutz Medical Campus, Aurora, Colorado; and Department of Medicine, Denver Health Hospital, Denver, Colorado (S.B.F)
| | - Raphael A Nemenoff
- Division of Renal Diseases and Hypertension (A.L., J.R.M., H.H., A.C.O., M.W.E., R.A.N., S.B.F.), Cardiovascular Pulmonary Research Laboratory, Department of Medicine (M.W.E., R.A.N.), University of Colorado Anschutz Medical Campus, Aurora, Colorado; and Department of Medicine, Denver Health Hospital, Denver, Colorado (S.B.F)
| | - Seth B Furgeson
- Division of Renal Diseases and Hypertension (A.L., J.R.M., H.H., A.C.O., M.W.E., R.A.N., S.B.F.), Cardiovascular Pulmonary Research Laboratory, Department of Medicine (M.W.E., R.A.N.), University of Colorado Anschutz Medical Campus, Aurora, Colorado; and Department of Medicine, Denver Health Hospital, Denver, Colorado (S.B.F)
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24
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Zhao L, Li AQ, Zhou TF, Zhang MQ, Qin XM. Exendin-4 alleviates angiotensin II-induced senescence in vascular smooth muscle cells by inhibiting Rac1 activation via a cAMP/PKA-dependent pathway. Am J Physiol Cell Physiol 2014; 307:C1130-41. [PMID: 25298426 DOI: 10.1152/ajpcell.00151.2014] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vascular aging has been implicated in the progression of diabetes and age-related cardiovascular disorders. Glucagon-like peptide-1 (GLP-1) is an incretin hormone capable of cytoprotective actions in addition to its glucose-lowering effect. The present study was undertaken to examine whether Exendin-4, a specific ligand for the GLP-1 receptor, could prevent angiotensin (ANG) II-induced premature senescence in vascular smooth muscle cells (VSMCs) and to determine the underlying mechanism involved. Senescence-associated β-galactosidase (SA β-gal) assay showed that ANG II induced premature senescence of VSMCs. Pretreatment with Exendin-4 significantly attenuated ANG II-induced generation of H2O2 and the subsequent VSMC senescence. These effects were, however, reversed in the presence of exendin fragment 9-39, a GLP-1 receptor antagonist, or PKI14-22. Moreover, a marked increase in the levels of p53 and p21 induced by ANG II was blunted by the treatment with Exendin-4. Nevertheless, Exendin-4 failed to decrease ANG II-induced expression of NAD(P)H oxidase 1 (Nox1), NAD(P)H oxidase 4 (Nox4), p22(phox), or p47(phox) in VSMCs. Mechanistically, Exendin-4 blocked ANG II-induced Rac1 activation through the cAMP/PKA signaling cascade. Specifically, NSC23766, a Rac1 inhibitor, abrogated the suppressive effects of Exendin-4 on ANG II-induced premature senescence and H2O2 generation, respectively. Thus Exendin-4 confers resistance to ANG II-induced superoxide anion generation from NAD(P)H oxidase and the resultant VSMC senescence by inhibiting Rac1 activation via a cAMP/PKA-dependent pathway. These findings demonstrate that GLP-1 as well as its analogs (GLP-1-related reagents) may hold therapeutic potential in the treatment of diabetes with cardiovascular disease.
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Affiliation(s)
- Liang Zhao
- Institute of Cardiovascular Science, Peking University Health Science Center, Beijing, China; and Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Ai Q Li
- Institute of Cardiovascular Science, Peking University Health Science Center, Beijing, China; and Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Teng F Zhou
- Institute of Cardiovascular Science, Peking University Health Science Center, Beijing, China; and Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Meng Q Zhang
- Institute of Cardiovascular Science, Peking University Health Science Center, Beijing, China; and Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Xiao M Qin
- Institute of Cardiovascular Science, Peking University Health Science Center, Beijing, China; and Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China
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25
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Ham SA, Lee H, Hwang JS, Kang ES, Yoo T, Paek KS, Do JT, Park C, Oh JW, Kim JH, Han CW, Seo HG. Activation of Peroxisome Proliferator-Activated Receptor δ Inhibits Angiotensin II-Induced Activation of Matrix Metalloproteinase-2 in Vascular Smooth Muscle Cells. J Vasc Res 2014; 51:221-30. [DOI: 10.1159/000365250] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 06/07/2014] [Indexed: 11/19/2022] Open
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26
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Speeckaert MM, Vanfraechem C, Speeckaert R, Delanghe JR. Peroxisome proliferator-activated receptor agonists in a battle against the aging kidney. Ageing Res Rev 2014; 14:1-18. [PMID: 24503003 DOI: 10.1016/j.arr.2014.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 01/24/2014] [Indexed: 12/19/2022]
Abstract
As aging is a complex phenomenon characterized by intraindividual and interindividual diversities in the maintenance of the homeostatic condition of cells and tissues, changes in renal function are not uniform and depend on associated diseases and environmental factors. Multiple studies have investigated the possible underlying mechanisms of age-related decline in kidney function. Evolutionary, molecular, cellular and systemic theories have been postulated to explain the primary disease independent age-related changes and adaptive responses. As peroxisome proliferator-activated receptors (PPARs) are involved in a broad spectrum of biological processes, PPAR activation might have an effect on the prevention of cell senescence. In this review, we will focus on the experimental and clinical evidence of PPAR agonists in a battle against the aging kidney.
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Affiliation(s)
| | | | | | - Joris R Delanghe
- Department of Clinical Chemistry, Ghent University Hospital, Gent, Belgium
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27
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Ding Y, Yang KD, Yang Q. The role of PPARδ signaling in the cardiovascular system. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2014; 121:451-73. [PMID: 24373246 DOI: 10.1016/b978-0-12-800101-1.00014-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Peroxisome proliferator-activated receptors (PPARα, β/δ, and γ), members of the nuclear receptor transcription factor superfamily, play important roles in the regulation of metabolism, inflammation, and cell differentiation. All three PPAR subtypes are expressed in the cardiovascular system with various expression patterns. Among the three PPAR subtypes, PPARδ is the least studied but has arisen as a potential therapeutic target for cardiovascular and many other diseases. It is known that PPARδ is ubiquitously expressed and abundantly expressed in cardiomyocytes. Accumulated evidence illustrates the role of PPARδ in regulating cardiovascular function and determining pathological progression. In this chapter, we will discuss the current knowledge in the role of PPARδ in the cardiovascular system, the mechanistic insights, and the potential therapeutic utilization for treating cardiovascular disease.
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Affiliation(s)
- Yishu Ding
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Kevin D Yang
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Qinglin Yang
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA
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28
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PTEN, Longevity and Age-Related Diseases. Biomedicines 2013; 1:17-48. [PMID: 28548055 PMCID: PMC5423463 DOI: 10.3390/biomedicines1010017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 11/26/2013] [Accepted: 12/09/2013] [Indexed: 02/08/2023] Open
Abstract
Since the discovery of PTEN, this protein has been shown to be an effective suppressor of cancer and a contributor to longevity. This report will review, in depth, the associations between PTEN and other molecules, its mutations and regulations in order to present how PTEN can be used to increase longevity. This report will collect recent research of PTEN and use this to discuss PTEN’s role in caloric restriction, antioxidative defense of DNA-damage and the role it plays in suppressing tumors. The report will also discuss that variety of ways that PTEN can be compromised, through mutations, complete loss of alleles and its main antagonist, the PI3K/AKT pathway.
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29
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Kim T, Yang Q. Peroxisome-proliferator-activated receptors regulate redox signaling in the cardiovascular system. World J Cardiol 2013; 5:164-174. [PMID: 23802046 PMCID: PMC3691497 DOI: 10.4330/wjc.v5.i6.164] [Citation(s) in RCA: 268] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 04/06/2013] [Accepted: 05/17/2013] [Indexed: 02/06/2023] Open
Abstract
Peroxisome-proliferator-activated receptors (PPARs) comprise three subtypes (PPARα, δ and γ) to form a nuclear receptor superfamily. PPARs act as key transcriptional regulators of lipid metabolism, mitochondrial biogenesis, and anti-oxidant defense. While their roles in regulating lipid metabolism have been well established, the role of PPARs in regulating redox activity remains incompletely understood. Since redox activity is an integral part of oxidative metabolism, it is not surprising that changes in PPAR signaling in a specific cell or tissue will lead to alteration of redox state. The effects of PPAR signaling are directly related to PPAR expression, protein activities and PPAR interactions with their coregulators. The three subtypes of PPARs regulate cellular lipid and energy metabolism in most tissues in the body with overlapping and preferential effects on different metabolic steps depending on a specific tissue. Adding to the complexity, specific ligands of each PPAR subtype may also display different potencies and specificities of their role on regulating the redox pathways. Moreover, the intensity and extension of redox regulation by each PPAR subtype are varied depending on different tissues and cell types. Both beneficial and adverse effects of PPAR ligands against cardiovascular disorders have been extensively studied by many groups. The purpose of the review is to summarize the effects of each PPAR on regulating redox and the underlying mechanisms, as well as to discuss the implications in the cardiovascular system.
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30
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Current world literature. Curr Opin Lipidol 2013; 24:178-81. [PMID: 23481230 DOI: 10.1097/mol.0b013e32835f8a8c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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31
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Kitagishi Y, Matsuda S. Redox regulation of tumor suppressor PTEN in cancer and aging (Review). Int J Mol Med 2013; 31:511-5. [PMID: 23313933 DOI: 10.3892/ijmm.2013.1235] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 12/18/2012] [Indexed: 11/05/2022] Open
Abstract
Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) has been shown to act as a tumor suppressor whose function includes important roles in regulating oxidative stress, indicating a potential role in oxidative damage-associated cancer. Accumulating evidence has revealed that PTEN also acts as a pivotal determinant of cell fate, regarding senescence and apoptosis, which is mediated by intracellular reactive oxygen species (ROS) generation. Cells are continuously exposed to ROS, which represent mutagens and are thought to be a major contributor to cancer and the aging process. Therefore, cellular ROS sensing and metabolism are firmly regulated by a variety of proteins involved in the redox mechanism. In this review, PTEN and the roles of oxidative stress in phosphoinositide-3 kinase/AKT signaling are summarized with a focus on the links between the pathways and ROS in cancer and aging.
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Affiliation(s)
- Yasuko Kitagishi
- Department of Environmental Health Science, Nara Women's University, Nara 630-8506, Japan
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32
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Freitas WM, Carvalho LSF, Moura FA, Sposito AC. Atherosclerotic disease in octogenarians: A challenge for science and clinical practice. Atherosclerosis 2012; 225:281-9. [DOI: 10.1016/j.atherosclerosis.2012.06.070] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 06/13/2012] [Accepted: 06/29/2012] [Indexed: 10/28/2022]
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33
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Kim MY, Kang ES, Ham SA, Hwang JS, Yoo TS, Lee H, Paek KS, Park C, Lee HT, Kim JH, Han CW, Seo HG. The PPARδ-mediated inhibition of angiotensin II-induced premature senescence in human endothelial cells is SIRT1-dependent. Biochem Pharmacol 2012; 84:1627-34. [PMID: 23000914 DOI: 10.1016/j.bcp.2012.09.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 09/13/2012] [Accepted: 09/13/2012] [Indexed: 12/26/2022]
Abstract
Cellular senescence has been implicated in endothelial dysfunctions affecting vascular tone and regeneration. The molecular mechanisms of vascular senescence are poorly understood. The present study demonstrates that upregulation of SIRT1 by peroxisome proliferator-activated receptor (PPAR) δ attenuates premature senescence in angiotensin (Ang) II-treated human coronary artery endothelial cells (HCAECs). Activation of PPARδ by the specific ligand GW501516 significantly inhibited Ang II-induced premature senescence and generation of reactive oxygen species (ROS) in HCAECs. A marked concentration- and time-dependent increase in the mRNA levels of SIRT1 was observed in GW501516-treated HCAECs. The effects of GW501516 were almost completely abolished in the presence of small interfering (si) RNA against PPARδ, indicating that PPARδ mediates the effects of GW501516. In addition, activation of PPARδ, but not PPARα or PPARγ, significantly enhanced SIRT1 promoter activity and protein expression. Down-regulation or inhibition of SIRT1 by siRNA or sirtinol abrogated the effects of PPARδ on Ang II-induced premature senescence and ROS generation, respectively. Furthermore, resveratrol, a well-known activator of SIRT1, mimicked the action of PPARδ on Ang II-induced premature senescence and ROS generation. Taken together, these results indicate that the anti-senescent activities of PPARδ may be achieved at least in part by fine tuning the expression of SIRT1 in the vascular endothelium.
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Affiliation(s)
- Min Young Kim
- Department of Pharmacology, Gyeongsang National University School of Medicine, Jinju 660-701, Republic of Korea
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