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Zeng X, Zhao H, Li Y, Fan J, Sun Y, Wang S, Wang Z, Song P, Ju D. Targeting Hedgehog signaling pathway and autophagy overcomes drug resistance of BCR-ABL-positive chronic myeloid leukemia. Autophagy 2016; 11:355-72. [PMID: 25701353 DOI: 10.4161/15548627.2014.994368] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The frontline tyrosine kinase inhibitor (TKI) imatinib has revolutionized the treatment of patients with chronic myeloid leukemia (CML). However, drug resistance is the major clinical challenge in the treatment of CML. The Hedgehog (Hh) signaling pathway and autophagy are both related to tumorigenesis, cancer therapy, and drug resistance. This study was conducted to explore whether the Hh pathway could regulate autophagy in CML cells and whether simultaneously regulating the Hh pathway and autophagy could induce cell death of drug-sensitive or -resistant BCR-ABL(+) CML cells. Our results indicated that pharmacological or genetic inhibition of Hh pathway could markedly induce autophagy in BCR-ABL(+) CML cells. Autophagic inhibitors or ATG5 and ATG7 silencing could significantly enhance CML cell death induced by Hh pathway suppression. Based on the above findings, our study demonstrated that simultaneously inhibiting the Hh pathway and autophagy could markedly reduce cell viability and induce apoptosis of imatinib-sensitive or -resistant BCR-ABL(+) cells. Moreover, this combination had little cytotoxicity in human peripheral blood mononuclear cells (PBMCs). Furthermore, this combined strategy was related to PARP cleavage, CASP3 and CASP9 cleavage, and inhibition of the BCR-ABL oncoprotein. In conclusion, this study indicated that simultaneously inhibiting the Hh pathway and autophagy could potently kill imatinib-sensitive or -resistant BCR-ABL(+) cells, providing a novel concept that simultaneously inhibiting the Hh pathway and autophagy might be a potent new strategy to overcome CML drug resistance.
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Key Words
- ACTB, actin
- AKT/protein kinase B, v-akt murine thymoma viral oncogene homolog
- ATG, autophagy-related
- BCC, basal cell carcinoma
- BCR-ABL
- BCR-ABL, breakpoint cluster region-ABL proto-oncogene, non-receptor tyrosine kinase
- Bafi A1, bafilomycin A1
- CASP, caspase
- CML
- CML, chronic myeloid leukemia
- CQ, chloroquine
- EIF4EBP1, eukaryotic translation initiation factor 4E binding protein 1
- HCQ, hydroxychloroquine
- Hh, Hedgehog
- MAP1LC3B, microtubule-associated protein 1 light chain 3 β
- MTOR, mechanistic target of rapamycin
- PARP, poly (ADP-ribose) polymerase
- PBMC, human peripheral blood mononuclear cell
- PCR, polymerase chain reaction
- RPS6KB, ribosomal protein S6 kinase, 70kDa
- SQSTM1, sequestosome 1
- TKI, tyrosine kinase inhibitor
- apoptosis-related cysteine peptidase
- autophagy
- drug resistance
- hedgehog pathway
- siRNA, small interfering RNA
- β
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Affiliation(s)
- Xian Zeng
- a Department of Biosynthesis and Key Laboratory of Smart Drug Delivery; MOE; School of Pharmacy ; Fudan University ; Shanghai , China
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Fan J, Zeng X, Li Y, Wang S, Yang P, Cao Z, Wang Z, Song P, Mei X, Ju D. A novel therapeutic approach against B-cell non-Hodgkin's lymphoma through co-inhibition of Hedgehog signaling pathway and autophagy. Tumour Biol 2015; 37:7305-14. [PMID: 26666826 DOI: 10.1007/s13277-015-4614-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 12/07/2015] [Indexed: 12/19/2022] Open
Abstract
B-cell non-Hodgkin's lymphoma (B-NHL) is one of the most common types of cancer in the world, with half of the patients dying due to the resistance or tolerance against the treatment. Thus, a novel therapeutic approach for B-NHL treatment was urgently needed. In this study, we investigated the potential of co-inhibition of Hedgehog signaling pathway (Hh) and autophagy in B-NHL therapy. We reported that vismodegib, an inhibitor of Hedgehog signaling pathway, could block the Hh pathway and induce cytotoxicity and apoptosis in B-NHL Raji cells. During this process, autophagy was activated as a response to Hh inhibition. Importantly, inhibition of autophagy potentiated the cytotoxicity and caspase 3-dependent apoptosis induced by vismodegib in B-NHL cells. Furthermore, clearance of ROS generation caused a decreased activity of autophagy and attenuated cytotoxicity in vismodegib-treated cells, while inhibition of autophagy accelerated the formation of ROS, indicating that ROS was required for vismodegib-induced autophagy and cytotoxicity in B-NHL cells. Our results demonstrated that co-inhibition of Hh pathway and autophagy could potently kill B-NHL cells and highlighted a novel approach for B-NHL therapy by co-inhibition of Hh pathway and cytoprotective autophagy.
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Affiliation(s)
- Jiajun Fan
- Department of Biosynthesis & Key Lab of Smart Drug Delivery MOE, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai, 201203, China
| | - Xian Zeng
- Department of Biosynthesis & Key Lab of Smart Drug Delivery MOE, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai, 201203, China
- Bioinformatics and Drug Design Group, Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Yubin Li
- Department of Biosynthesis & Key Lab of Smart Drug Delivery MOE, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai, 201203, China
| | - Shaofei Wang
- Department of Biosynthesis & Key Lab of Smart Drug Delivery MOE, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai, 201203, China
| | - Ping Yang
- Instrumental Analysis Center, School of Pharmacy, Fudan University, Shanghai, China
| | - Zhonglian Cao
- Instrumental Analysis Center, School of Pharmacy, Fudan University, Shanghai, China
| | - Ziyu Wang
- Department of Biosynthesis & Key Lab of Smart Drug Delivery MOE, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai, 201203, China
| | - Ping Song
- Department of Biosynthesis & Key Lab of Smart Drug Delivery MOE, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai, 201203, China
| | - Xiaobin Mei
- Department of Nephrology, Changhai Hospital, Second Military Medical University, Shanghai, 200433, China.
| | - Dianwen Ju
- Department of Biosynthesis & Key Lab of Smart Drug Delivery MOE, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai, 201203, China.
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Hedgehog and Resident Vascular Stem Cell Fate. Stem Cells Int 2015; 2015:468428. [PMID: 26064136 PMCID: PMC4438189 DOI: 10.1155/2015/468428] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 04/01/2015] [Indexed: 01/20/2023] Open
Abstract
The Hedgehog pathway is a pivotal morphogenic driver during embryonic development and a key regulator of adult stem cell self-renewal. The discovery of resident multipotent vascular stem cells and adventitial progenitors within the vessel wall has transformed our understanding of the origin of medial and neointimal vascular smooth muscle cells (SMCs) during vessel repair in response to injury, lesion formation, and overall disease progression. This review highlights the importance of components of the Hh and Notch signalling pathways within the medial and adventitial regions of adult vessels, their recapitulation following vascular injury and disease progression, and their putative role in the maintenance and differentiation of resident vascular stem cells to vascular lineages from discrete niches within the vessel wall.
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54
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Vindis C. Autophagy: an emerging therapeutic target in vascular diseases. Br J Pharmacol 2015; 172:2167-78. [PMID: 25537552 DOI: 10.1111/bph.13052] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 11/27/2014] [Accepted: 12/07/2014] [Indexed: 12/13/2022] Open
Abstract
Autophagy is a cellular catabolic process responsible for the destruction of long-lived proteins and organelles via lysosome-dependent pathway. This process is of great importance in maintaining cellular homeostasis, and deregulated autophagy has been implicated in the pathogenesis of a wide range of diseases. A growing body of evidence suggests that autophagy can be activated in vascular disorders such as atherosclerosis. Autophagy occurs under basal conditions and mediates homeostatic functions in cells but in the setting of pathological states up-regulated autophagy can exert both protective and detrimental functions. Therefore, the precise role of autophagy and its relationship with the progression of the disease need to be clarified. This review highlights recent findings regarding autophagy activity in vascular cells and its potential contribution to vascular disorders with a focus on atherogenesis. Finally, whether the manipulation of autophagy represents a new therapeutic approach to treat or prevent vascular diseases is also discussed.
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Affiliation(s)
- Cécile Vindis
- Inserm, UMR-1048, Institute of Metabolic and Cardiovascular Diseases, Toulouse, France; University of Toulouse III, Toulouse, France
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Abstract
Autophagy is a reparative, life-sustaining process by which cytoplasmic components are sequestered in double-membrane vesicles and degraded on fusion with lysosomal compartments. Growing evidence reveals that basal autophagy is an essential in vivo process mediating proper vascular function. Moreover, autophagy is stimulated by many stress-related stimuli in the arterial wall to protect endothelial cells and smooth muscle cells against cell death and the initiation of vascular disease, in particular atherosclerosis. Basal autophagy is atheroprotective during early atherosclerosis but becomes dysfunctional in advanced atherosclerotic plaques. Little is known about autophagy in other vascular disorders, such as aneurysm formation, arterial aging, vascular stiffness, and chronic venous disease, even though autophagy is often impaired. This finding highlights the need for pharmacological interventions with compounds that stimulate the prosurvival effects of autophagy in the vasculature. A large number of animal studies and clinical trials have indicated that oral or stent-based delivery of the autophagy inducer rapamycin or derivatives thereof, collectively known as rapalogs, effectively inhibit the basic mechanisms that control growth and destabilization of atherosclerotic plaques. Other autophagy-inducing drugs, such as spermidine or add-on therapy with widely used antiatherogenic compounds, including statins and metformin, are potentially useful to prevent vascular disease with minimal adverse effects.
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Affiliation(s)
- Guido R.Y. De Meyer
- From the Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Mandy O.J. Grootaert
- From the Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Cédéric F. Michiels
- From the Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Ammar Kurdi
- From the Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Dorien M. Schrijvers
- From the Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
| | - Wim Martinet
- From the Laboratory of Physiopharmacology, University of Antwerp, Antwerp, Belgium
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Abstract
Cardiovascular disease is the leading cause of death worldwide. As such, there is great interest in identifying novel mechanisms that govern the cardiovascular response to disease-related stress. First described in failing hearts, autophagy within the cardiovascular system has been widely characterized in cardiomyocytes, cardiac fibroblasts, endothelial cells, vascular smooth muscle cells, and macrophages. In all cases, a window of optimal autophagic activity appears to be critical to the maintenance of cardiovascular homeostasis and function; excessive or insufficient levels of autophagic flux can each contribute to heart disease pathogenesis. In this Review, we discuss the potential for targeting autophagy therapeutically and our vision for where this exciting biology may lead in the future.
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Salabei JK, Hill BG. Autophagic regulation of smooth muscle cell biology. Redox Biol 2014; 4:97-103. [PMID: 25544597 PMCID: PMC4309847 DOI: 10.1016/j.redox.2014.12.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 12/15/2014] [Indexed: 01/09/2023] Open
Abstract
Autophagy regulates the metabolism, survival, and function of numerous cell types, including those comprising the cardiovascular system. In the vasculature, changes in autophagy have been documented in atherosclerotic and restenotic lesions and in hypertensive vessels. The biology of vascular smooth muscle cells appears particularly sensitive to changes in the autophagic program. Recent evidence indicates that stimuli or stressors evoked during the course of vascular disease can regulate autophagic activity, resulting in modulation of VSMC phenotype and viability. In particular, certain growth factors and cytokines, oxygen tension, and pharmacological drugs have been shown to trigger autophagy in smooth muscle cells. Importantly, each of these stimuli has a redox component, typically associated with changes in the abundance of reactive oxygen, nitrogen, or lipid species. Collective findings support the hypothesis that autophagy plays a critical role in vascular remodeling by regulating smooth muscle cell phenotype transitions and by influencing the cellular response to stress. In this graphical review, we summarize current knowledge on the role of autophagy in the biology of the smooth muscle cell in (patho)physiology.
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Affiliation(s)
- Joshua K Salabei
- Institute of Molecular Cardiology, Department of Medicine, University of Louisville, Louisville, KY, USA; Diabetes and Obesity Center, Department of Medicine, University of Louisville, Louisville, KY, USA
| | - Bradford G Hill
- Institute of Molecular Cardiology, Department of Medicine, University of Louisville, Louisville, KY, USA; Diabetes and Obesity Center, Department of Medicine, University of Louisville, Louisville, KY, USA; Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, KY, USA; Department of Physiology and Biophysics, University of Louisville, Louisville, KY, USA.
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Ye LX, Yu J, Liang YX, Zeng JS, Huang RX, Liao SJ. Beclin 1 knockdown retards re-endothelialization and exacerbates neointimal formation via a crosstalk between autophagy and apoptosis. Atherosclerosis 2014; 237:146-54. [DOI: 10.1016/j.atherosclerosis.2014.08.052] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 08/13/2014] [Accepted: 08/28/2014] [Indexed: 01/15/2023]
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Orhon I, Dupont N, Pampliega O, Cuervo AM, Codogno P. Autophagy and regulation of cilia function and assembly. Cell Death Differ 2014; 22:389-97. [PMID: 25361082 DOI: 10.1038/cdd.2014.171] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 09/05/2014] [Accepted: 09/10/2014] [Indexed: 12/21/2022] Open
Abstract
Motile and primary cilia (PC) are microtubule-based structures located at the cell surface of many cell types. Cilia govern cellular functions ranging from motility to integration of mechanical and chemical signaling from the environment. Recent studies highlight the interplay between cilia and autophagy, a conserved cellular process responsible for intracellular degradation. Signaling from the PC recruits the autophagic machinery to trigger autophagosome formation. Conversely, autophagy regulates ciliogenesis by controlling the levels of ciliary proteins. The cross talk between autophagy and ciliated structures is a novel aspect of cell biology with major implications in development, physiology and human pathologies related to defects in cilium function.
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Affiliation(s)
- I Orhon
- 1] INSERM U1151-CNRS UMR 8253, Paris, France [2] Institut Necker Enfants-Malades (INEM), Paris, France [3] Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - N Dupont
- 1] INSERM U1151-CNRS UMR 8253, Paris, France [2] Institut Necker Enfants-Malades (INEM), Paris, France [3] Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - O Pampliega
- 1] Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA [2] Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY, USA
| | - A M Cuervo
- 1] Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA [2] Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY, USA
| | - P Codogno
- 1] INSERM U1151-CNRS UMR 8253, Paris, France [2] Institut Necker Enfants-Malades (INEM), Paris, France [3] Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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60
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Wang J, Gu S, Huang J, Chen S, Zhang Z, Xu M. Inhibition of autophagy potentiates the efficacy of Gli inhibitor GANT-61 in MYCN-amplified neuroblastoma cells. BMC Cancer 2014; 14:768. [PMID: 25323222 PMCID: PMC4210511 DOI: 10.1186/1471-2407-14-768] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 10/10/2014] [Indexed: 12/21/2022] Open
Abstract
Background Aberrant Hedgehog (Hh) signaling is often associated with neuroblastoma (NB), a childhood malignancy with varying clinical outcomes due to different molecular characteristics. Inhibition of Hh signaling with small molecule inhibitors, particularly with GANT-61, significantly suppresses NB growth. However, NB with MYCN amplification is less sensitive to GANT-61 than those without MYCN amplification. Methods Autophagic process was examined in two MYCN amplified and two MYCN non-amplified NB cells treated with GANT-61. Subsequently, chemical and genetic approaches were applied with GANT-61 together to evaluate the role of autophagy in GANT-61 induced cell death. Results Here we show that GANT-61 enhanced autophagy in MYCN amplified NB cells. Both an autophagic inhibitor 3-methyladenine (3-MA) and genetic disruption of ATG5 or ATG7 expression suppressed GANT-61 induced autophagy and significantly increased apoptotic cell death, whereas pre-treatment with an apoptotic inhibitor, Z-VAD-FMK, rescued GANT-61 induced cell death and had no effect on the autophagic process. In the other hand, GANT-61 barely induced autophagy in MYCN non-amplified NB cells, but overexpression of MYCN in MYCN non-amplified NB cells recapitulated GANT-61 induced autophagy seen in MYCN amplified NB cells, suggesting that the level of GANT-61 induced autophagy in NB cells is related to MYCN expression level in cells. Conclusion Aberrant Hh signaling activation as an oncogenic driver in NB renders inhibition of Hh signaling an effective measure to suppress NB growth. However, our data suggest that enhanced autophagy concomitant with Hh signaling inhibition acts as a pro-survival factor to maintain cell viability, which reduces GANT-61 efficacy. Besides, MYCN amplification is likely involved in the induction of the pro-survival autophagy. Overall, simultaneous inhibition of both Hh signaling and autophagy could be a better way to treat MYCN amplified NB. Electronic supplementary material The online version of this article (doi:10.1186/1471-2407-14-768) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | - Zhen Zhang
- Department of Surgery, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai 200127, China.
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Loss of Sonic hedgehog leads to alterations in intestinal secretory cell maturation and autophagy. PLoS One 2014; 9:e98751. [PMID: 24887421 PMCID: PMC4041759 DOI: 10.1371/journal.pone.0098751] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 05/07/2014] [Indexed: 12/22/2022] Open
Abstract
Background Intestinal epithelial cells express the Sonic and Indian hedgehog ligands. Despite the strong interest in gut hedgehog signaling in GI diseases, no studies have specifically addressed the singular role of intestinal epithelial cell Sonic hedgehog signaling. The aim of this study was to investigate the specific role of Sonic hedgehog in adult ileal epithelial homeostasis. Methodology/Principal Findings A Sonic hedgehog intestinal epithelial conditional knockout mouse model was generated. Assessment of ileal histological abnormalities, crypt epithelial cell proliferation, epithelial cell fate, junctional proteins, signaling pathways, as well as ultrastructural analysis of intracellular organelles were performed in control and mutant mice. Mice lacking intestinal epithelial Sonic Hedgehog displayed decreased ileal crypt/villus length, decreased crypt proliferation as well as a decrease in the number of ileal mucin-secreting goblet cells and antimicrobial peptide-secreting Paneth cells during adult life. These secretory cells also exhibited disruption of their secretory products in mutant mice. Ultrastructural microscopy analysis revealed a dilated ER lumen in secretory cells. This phenotype was also associated with a decrease in autophagy. Conclusions/Significance Altogether, these findings indicate that the loss of Sonic hedgehog can lead to ileal secretory cell modifications indicative of endoplasmic reticulum stress, accompanied by a significant reduction in autophagy.
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Li J, Zhao L, Yang T, Zeng YJ, Yang K. c-Ski inhibits autophagy of vascular smooth muscle cells induced by oxLDL and PDGF. PLoS One 2014; 9:e98902. [PMID: 24887307 PMCID: PMC4041777 DOI: 10.1371/journal.pone.0098902] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 05/08/2014] [Indexed: 12/27/2022] Open
Abstract
Autophagy is increasingly being recognized as a critical determinant of vascular smooth muscle cell (VSMC) biology. Previously, we have demonstrated that c-Ski inhibits VSMC proliferation stimulated by transforming growth factor β (TGF-β), but it is not clear whether c-Ski has the similar protective role against other vascular injury factors and whether regulation of autophagy is involved in its protective effects on VSMC. Accordingly, in this study, rat aortic A10 VSMCs were treated with 40 µg/ml oxidized low-density lipoprotein (oxLDL) or 20 ng/ml platelet-derived growth factor (PDGF), both of which were autophagy inducers and closely related to the abnormal proliferation of VSMCs. Overexpression of c-Ski in A10 cells significantly suppressed the oxLDL- and PDGF- induced autophagy. This action of c-Ski resulted in inhibiting the cell proliferation, the decrease of contractile phenotype marker α-SMA expression while the increase of synthetic phenotype marker osteopontin expression stimulated by oxLDL or PDGF. Inversely, knockdown of c-Ski by RNAi enhanced the stimulatory effects of oxLDL or PDGF on A10 cell growth and phenotype transition. And further investigation found that inhibition of AKT phosphorylation to downregulate proliferating cell nuclear antigen (PCNA) expression, was involved in the regulation of autophagy and associated functions by c-Ski in the oxLDL- and PDGF-stimulated VSMCs. Collectively, c-Ski may play an important role in inhibiting autophagy to protect VSMCs against some harsh stress including oxLDL and PDGF.
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Affiliation(s)
- Jun Li
- Department of Cardiothoracic Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China
- * E-mail:
| | - Li Zhao
- Department of Biochemistry and Molecular Biology, Third Military Medical University, Chongqing, China
| | - Ting Yang
- Department of Biochemistry and Molecular Biology, Third Military Medical University, Chongqing, China
| | - Yi-Jun Zeng
- Department of Biochemistry and Molecular Biology, Third Military Medical University, Chongqing, China
| | - Kang Yang
- Department of Cardiothoracic Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China
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Hale AN, Ledbetter DJ, Gawriluk TR, Rucker EB. Autophagy: regulation and role in development. Autophagy 2014; 9:951-72. [PMID: 24121596 DOI: 10.4161/auto.24273] [Citation(s) in RCA: 245] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Autophagy is an evolutionarily conserved cellular process through which long-lived proteins and damaged organelles are recycled to maintain energy homeostasis. These proteins and organelles are sequestered into a double-membrane structure, or autophagosome, which subsequently fuses with a lysosome in order to degrade the cargo. Although originally classified as a type of programmed cell death, autophagy is more widely viewed as a basic cell survival mechanism to combat environmental stressors. Autophagy genes were initially identified in yeast and were found to be necessary to circumvent nutrient stress and starvation. Subsequent elucidation of mammalian gene counterparts has highlighted the importance of this process to normal development. This review provides an overview of autophagy, the types of autophagy, its regulation and its known impact on development gleaned primarily from murine models.
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Affiliation(s)
- Amber N Hale
- Department of Biology; University of Kentucky; Lexington, KY USA
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Madigan M, Entabi F, Zuckerbraun B, Loughran P, Tzeng E. Delayed inhaled carbon monoxide mediates the regression of established neointimal lesions. J Vasc Surg 2014; 61:1026-33. [PMID: 24418641 DOI: 10.1016/j.jvs.2013.11.072] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 11/12/2013] [Accepted: 11/17/2013] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Intimal hyperplasia (IH) contributes to the failure of vascular interventions. While many investigational therapies inhibit the development of IH in animal models, few of these potential therapies can reverse established lesions. Inhaled carbon monoxide (CO) dramatically inhibits IH in both rats and pigs when given perioperatively. It also prevented the development of pulmonary arterial hypertension in rodents. Interestingly, CO could reverse pulmonary artery structural changes and right heart hemodynamic changes when administered after the establishment of pulmonary hypertension. Thus, we hypothesize that inhaled CO may mediate the regression of established neointimal lesions. METHODS Rats underwent carotid artery balloon angioplasty injury. Carotid arteries were collected at 2 and 4 weeks after injury for morphometric analysis of the neointima. Another group was treated with inhaled CO (250 parts per million) for 1 hour daily from week 2 until week 4. Additional rats were sacrificed 3 days after initiating CO treatment, and the carotid arteries were examined for apoptosis by terminal deoxynucleotidyl transferase dUTP nick end-labeling, proliferation by Ki67 staining, and autophagy by microtubule-associated protein light chain 3 I/II staining. RESULTS At 2 weeks following injury, sizable neointimal lesions had developed (intimal/media = 0.92 ± 0.22). By 4 weeks, lesion size remained stable (0.80 ± 0.09). Delayed inhaled CO treatment greatly reduced neointimal lesion size vs the 2- and 4-week control mice (0.38 ± 0.05; P < .05). Arteries from the CO-treated rats exhibited significantly reduced apoptosis compared with control vessels (3.18% ± 1.94% vs 16.26% ± 5.91%; P = .036). Proliferation was also dramatically reduced in the CO-treated animals (2.98 ± 1.55 vs 10.37 ± 2.80; P = .036). No difference in autophagy between control and CO-treated rats was detected. CONCLUSIONS Delayed administration of inhaled CO reduced established neointimal lesion size. This effect was mediated by the antiproliferative effect of CO on medial and intimal smooth muscle cells without increases in arterial wall apoptosis or autophagy. Future studies will examine additional time points to determine if there is temporal variation in the rates of apoptosis and autophagy.
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Affiliation(s)
- Michael Madigan
- Department of Veterans Affairs Medical Center, University of Pittsburgh, Pittsburgh, Pa; Division of Vascular Surgery, University of Pittsburgh, Pittsburgh, Pa
| | - Fateh Entabi
- Department of Veterans Affairs Medical Center, University of Pittsburgh, Pittsburgh, Pa; Division of Vascular Surgery, University of Pittsburgh, Pittsburgh, Pa
| | - Brian Zuckerbraun
- Department of Veterans Affairs Medical Center, University of Pittsburgh, Pittsburgh, Pa; Department of Surgery, University of Pittsburgh, Pittsburgh, Pa
| | - Patricia Loughran
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pa; Center of Biologic Imaging, University of Pittsburgh, Pittsburgh, Pa
| | - Edith Tzeng
- Department of Veterans Affairs Medical Center, University of Pittsburgh, Pittsburgh, Pa; Division of Vascular Surgery, University of Pittsburgh, Pittsburgh, Pa.
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Salabei JK, Hill BG. Implications of autophagy for vascular smooth muscle cell function and plasticity. Free Radic Biol Med 2013; 65:693-703. [PMID: 23938401 PMCID: PMC3859773 DOI: 10.1016/j.freeradbiomed.2013.08.003] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 08/02/2013] [Accepted: 08/04/2013] [Indexed: 12/14/2022]
Abstract
Vascular smooth muscle cells (VSMCs) are fundamental in regulating blood pressure and distributing oxygen and nutrients to peripheral tissues. They also possess remarkable plasticity, with the capacity to switch to synthetic, macrophage-like, or osteochondrogenic phenotypes when cued by external stimuli. In arterial diseases such as atherosclerosis and restenosis, this plasticity seems to be critical and, depending on the disease context, can be deleterious or beneficial. Therefore, understanding the mechanisms regulating VSMC phenotype and survival is essential for developing new therapies for vascular disease as well as understanding how secondary complications due to surgical interventions develop. In this regard, the cellular process of autophagy is increasingly being recognized as a major player in vascular biology and a critical determinant of VSMC phenotype and survival. Although autophagy was identified in lesional VSMCs in the 1960s, our understanding of the implications of autophagy in arterial diseases and the stimuli promoting its activation in VSMCs is only now being elucidated. In this review, we highlight the evidence for autophagy occurring in VSMCs in vivo, elaborate on the stimuli and processes regulating autophagy, and discuss the current understanding of the role of autophagy in vascular disease.
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Affiliation(s)
- Joshua K Salabei
- Diabetes and Obesity Center, Institute of Molecular Cardiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Bradford G Hill
- Diabetes and Obesity Center, Institute of Molecular Cardiology, University of Louisville School of Medicine, Louisville, KY 40202, USA; Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, Louisville, KY 40202, USA; Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, KY 40202, USA.
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Pampliega O, Orhon I, Patel B, Sridhar S, Díaz-Carretero A, Beau I, Codogno P, Satir B, Satir P, Cuervo AM. Functional interaction between autophagy and ciliogenesis. Nature 2013; 502:194-200. [PMID: 24089209 PMCID: PMC3896125 DOI: 10.1038/nature12639] [Citation(s) in RCA: 328] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 09/10/2013] [Indexed: 12/18/2022]
Abstract
Nutrient deprivation is a stimulus shared by both autophagy and the formation of primary cilia. The recently discovered role of primary cilia in nutrient sensing and signalling motivated us to explore the possible functional interactions between this signalling hub and autophagy. Here we show that part of the molecular machinery involved in ciliogenesis also participates in the early steps of the autophagic process. Signalling from the cilia, such as that from the Hedgehog pathway, induces autophagy by acting directly on essential autophagy-related proteins strategically located in the base of the cilium by ciliary trafficking proteins. Whereas abrogation of ciliogenesis partially inhibits autophagy, blockage of autophagy enhances primary cilia growth and cilia-associated signalling during normal nutritional conditions. We propose that basal autophagy regulates ciliary growth through the degradation of proteins required for intraflagellar transport. Compromised ability to activate the autophagic response may underlie some common ciliopathies.
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Affiliation(s)
- Olatz Pampliega
- Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Idil Orhon
- INSERM U845; Paris-Descartes University, Paris, France
- INSERM U984; University Paris-Sud 11; Châtenay-Malabry, France
| | - Bindi Patel
- Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Sunandini Sridhar
- Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Antonio Díaz-Carretero
- Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Isabelle Beau
- INSERM U984; University Paris-Sud 11; Châtenay-Malabry, France
| | - Patrice Codogno
- INSERM U845; Paris-Descartes University, Paris, France
- INSERM U984; University Paris-Sud 11; Châtenay-Malabry, France
| | - Birgit Satir
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Peter Satir
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ana Maria Cuervo
- Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Salabei JK, Cummins TD, Singh M, Jones SP, Bhatnagar A, Hill BG. PDGF-mediated autophagy regulates vascular smooth muscle cell phenotype and resistance to oxidative stress. Biochem J 2013; 451:375-88. [PMID: 23421427 PMCID: PMC4040966 DOI: 10.1042/bj20121344] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Vascular injury and chronic arterial diseases result in exposure of VSMCs (vascular smooth muscle cells) to increased concentrations of growth factors. The mechanisms by which growth factors trigger VSMC phenotype transitions remain unclear. Because cellular reprogramming initiated by growth factors requires not only the induction of genes involved in cell proliferation, but also the removal of contractile proteins, we hypothesized that autophagy is an essential modulator of VSMC phenotype. Treatment of VSMCs with PDGF (platelet-derived growth factor)-BB resulted in decreased expression of the contractile phenotype markers calponin and α-smooth muscle actin and up-regulation of the synthetic phenotype markers osteopontin and vimentin. Autophagy, as assessed by LC3 (microtubule-associated protein light chain 3 α; also known as MAP1LC3A)-II abundance, LC3 puncta formation and electron microscopy, was activated by PDGF exposure. Inhibition of autophagy with 3-methyladenine, spautin-1 or bafilomycin stabilized the contractile phenotype. In particular, spautin-1 stabilized α-smooth muscle cell actin and calponin in PDGF-treated cells and prevented actin filament disorganization, diminished production of extracellular matrix, and abrogated VSMC hyperproliferation and migration. Treatment of cells with PDGF prevented protein damage and cell death caused by exposure to the lipid peroxidation product 4-hydroxynonenal. The results of the present study demonstrate a distinct form of autophagy induced by PDGF that is essential for attaining the synthetic phenotype and for survival under the conditions of high oxidative stress found to occur in vascular lesions.
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MESH Headings
- Actins/genetics
- Actins/metabolism
- Adenine/analogs & derivatives
- Adenine/pharmacology
- Aldehydes/pharmacology
- Animals
- Aorta/cytology
- Aorta/drug effects
- Aorta/metabolism
- Autophagy/drug effects
- Autophagy/genetics
- Biomarkers/metabolism
- Calcium-Binding Proteins/genetics
- Calcium-Binding Proteins/metabolism
- Gene Expression Regulation/drug effects
- Macrolides/pharmacology
- Male
- Microfilament Proteins/genetics
- Microfilament Proteins/metabolism
- Microtubule-Associated Proteins/genetics
- Microtubule-Associated Proteins/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Osteopontin/genetics
- Osteopontin/metabolism
- Oxidative Stress
- Phenotype
- Platelet-Derived Growth Factor/pharmacology
- Primary Cell Culture
- Rats
- Rats, Sprague-Dawley
- Signal Transduction/drug effects
- Vimentin/genetics
- Vimentin/metabolism
- Calponins
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Affiliation(s)
- Joshua K. Salabei
- Diabetes and Obesity Center and Institute of Molecular Cardiology, University of Louisville School of Medicine, Louisville, KY 40202
- Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Timothy D. Cummins
- Diabetes and Obesity Center and Institute of Molecular Cardiology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Mahavir Singh
- Diabetes and Obesity Center and Institute of Molecular Cardiology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Steven P. Jones
- Diabetes and Obesity Center and Institute of Molecular Cardiology, University of Louisville School of Medicine, Louisville, KY 40202
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, KY 40202
| | - Aruni Bhatnagar
- Diabetes and Obesity Center and Institute of Molecular Cardiology, University of Louisville School of Medicine, Louisville, KY 40202
- Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, Louisville, KY 40202
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, KY 40202
| | - Bradford G. Hill
- Diabetes and Obesity Center and Institute of Molecular Cardiology, University of Louisville School of Medicine, Louisville, KY 40202
- Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, Louisville, KY 40202
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, KY 40202
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Petralia RS, Schwartz CM, Wang YX, Kawamoto EM, Mattson MP, Yao PJ. Sonic hedgehog promotes autophagy in hippocampal neurons. Biol Open 2013; 2:499-504. [PMID: 23789099 PMCID: PMC3654269 DOI: 10.1242/bio.20134275] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 03/20/2013] [Indexed: 01/07/2023] Open
Abstract
The Sonic hedgehog (Shh) signaling pathway is well known in patterning of the neural tube during embryonic development, but its emerging role in differentiated neurons is less understood. Here we report that Shh enhances autophagy in cultured hippocampal neurons. Microarray analysis reveals the upregulation of multiple autophagy-related genes in neurons in response to Shh application. Through analysis of the autophagy-marker LC3 by immunoblot analysis and immunocytochemistry, we confirm activation of the autophagy pathway in Shh-exposed neurons. Using electron microscopy, we find autophagosomes and associated structures with a wide range of morphologies in synaptic terminals of Shh-exposed neurons. Moreover, we show that Shh-triggered autophagy depends on class III Phosphatidylinositol 3-kinase complexes (PtdIns3K). These results identify a link between Shh and autophagy pathways and, importantly, provide a lead for further understanding the physiology of Shh signaling activity in neurons.
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69
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Gebhardt R, Coffer PJ. Hepatic autophagy is differentially regulated in periportal and pericentral zones - a general mechanism relevant for other tissues? Cell Commun Signal 2013; 11:21. [PMID: 23531205 PMCID: PMC3623826 DOI: 10.1186/1478-811x-11-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 03/11/2013] [Indexed: 02/08/2023] Open
Abstract
Background Liver zonation, the fact that metabolic pathways are spatially separated along the liver sinusoids, is fundamental for proper functioning of this organ. For example, glutamine synthesis from glutamate and ammonia is localized pericentrally in only 7% of the hepatocytes concentrically arranged around the central veins. Recently, we found that FOXO transcription factors lead to upregulation of glutamine synthetase expression inducing autophagy via increasing glutamine production. Since in liver this mechanism can only be functioning in the pericentral zone it remains unclear how autophagy might be regulated in the rest of liver parenchyma. Presentation of the hypothesis We hypothesize that the regulation of autophagy by glutamine in liver is zonated. In the periportal zone, autophagy is inhibited by low intracellular glutamine but high essential amino acids, while in the pericentral zone it is stimulated by high intracellular glutamine. This zonation may be controlled by the Wnt and Hedgehog signalling pathways through reciprocal influence on the expression of amino acid transporters and metabolic enzymes in the different zones of the parenchyma. Testing the hypothesis The hypothesis can be tested in transgenic mice with conditional hepatocyte-specific modulation of Wnt and Hedgehog signalling. Isolated periportal and pericentral hepatocyte populations allow for determining the different activities of autophagy and its regulating mechanisms in different zones of the parenchyma. Implications of the hypothesis Zonation of the regulation of autophagy may allow adapting the extent of the proteolytic breakdown of proteins and organelles to different physiological needs in different zones of liver parenchyma. In this manner metabolic functions can be supported in one zone, for example maintenance of blood glucose levels during starvation which is a periportal issue, while simultaneously preventing cytotoxic events in the opposite zone. Likewise, lipid metabolism can be differentially influenced by uncoupling periportal lipophagy from pericentral breakdown of peroxisomes. Further implications concern the shaping of morphogen gradients along the sinusoidal axis by autophagy, and the different contribution of autophagy to the development of various different liver pathologies. The proposed dependence of the dual glutamine-dependent regulatory mechanisms of autophagy on inverse gradients of Wnt and hedgehog signalling may be relevant for other tissues in which GS is heterogeneously expressed.
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Affiliation(s)
- Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Leipzig, Germany.
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