1
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Tang Z, Ding Y, Zhang R, Zhang M, Guan Q, Zhang L, Wang H, Chen Y, Jiang R, Zhang W, Wang J. Genetic polymorphisms of Ca 2+ transport proteins and molecular chaperones in mitochondria-associated endoplasmic reticulum membrane and non-alcoholic fatty liver disease. Front Endocrinol (Lausanne) 2023; 13:1056283. [PMID: 36686460 PMCID: PMC9846251 DOI: 10.3389/fendo.2022.1056283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 12/13/2022] [Indexed: 01/05/2023] Open
Abstract
Background Non-alcoholic fatty liver disease (NAFLD) is recognized to be closely associated with endoplasmic reticulum stress and mitochondrial dysfunction, while previous studies have emphasized the important role of calcium homeostasis from the mitochondria-associated endoplasmic reticulum membrane (MAM) in the endoplasmic reticulum and mitochondria. This article will assess the association between genetic polymorphisms of Ca2+ transport proteins and molecular chaperones in MAM and NAFLD risk. Methods A case-control study was conducted in a community of Nanjing, China during April to December 2020. 2701 subjects were enrolled and genotyped for 6 genetic variants in HSPA5 and ITPR2 genes. Logistic regression analysis was used to assess impact of these variants on NAFLD risk. Results After adjusting for age, gender, total cholesterol and glucose, we identified that HSPA5 rs12009 variant genotypes (recessive model: OR= 0.801, 95% CI= 0.652-0.986, P= 0.036), rs430397 variant genotypes (recessive model: OR= 0.546, 95% CI= 0.314-0.950, P= 0.032), and ITPR2 rs11048570 variant genotypes (recessive model: OR= 0.673, 95% CI= 0.453-0.999, P= 0.049) were associated with a reduced risk of NAFLD. Multivariate stepwise regression analysis indicated that gender, glucose, body mass index, triglycerides and favorable alleles were independent influencers of NAFLD (all P< 0.05). The area under the receiver operating characteristic curve was 0.764 (95% CI= 0.745-0.783, P< 0.001). Conclusion The variant genotypes of Ca2+ transport-associated genes HSPA5 (rs12009 and rs430397) and ITPR2 (rs11048570) might contribute to the reduction of the NAFLD risk in Chinese Han population, which can provide new insight into NAFLD pathogenesis.
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Affiliation(s)
- Zongzhe Tang
- Department of Fundamental and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, China
| | - Yajie Ding
- Department of Fundamental and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, China
| | - Ru Zhang
- Department of Fundamental and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, China
| | - Mengting Zhang
- Department of Fundamental and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, China
| | - Qing Guan
- Department of Fundamental and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, China
| | - Liuxin Zhang
- Department of Neurosurgery, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Hongliang Wang
- Department of General Practice, Ninghai Road Community Health Service Center, Nanjing, China
| | - Yue Chen
- Department of Fundamental and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, China
| | - Rong Jiang
- Department of Fundamental and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, China
| | - Wei Zhang
- Department of Epidemiology, Shanghai Cancer Institute, Shanghai, China
| | - Jie Wang
- Department of Fundamental and Community Nursing, School of Nursing, Nanjing Medical University, Nanjing, China
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2
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Li H, Wen W, Luo J. Targeting Endoplasmic Reticulum Stress as an Effective Treatment for Alcoholic Pancreatitis. Biomedicines 2022; 10:biomedicines10010108. [PMID: 35052788 PMCID: PMC8773075 DOI: 10.3390/biomedicines10010108] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/28/2021] [Accepted: 12/30/2021] [Indexed: 02/04/2023] Open
Abstract
Pancreatitis and alcoholic pancreatitis are serious health concerns with an urgent need for effective treatment strategies. Alcohol is a known etiological factor for pancreatitis, including acute pancreatitis (AP) and chronic pancreatitis (CP). Excessive alcohol consumption induces many pathological stress responses; of particular note is endoplasmic reticulum (ER) stress and adaptive unfolded protein response (UPR). ER stress results from the accumulation of unfolded/misfolded protein in the ER and is implicated in the pathogenesis of alcoholic pancreatitis. Here, we summarize the possible mechanisms by which ER stress contributes to alcoholic pancreatitis. We also discuss potential approaches targeting ER stress and UPR in developing novel therapeutic strategies for the disease.
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Affiliation(s)
- Hui Li
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (H.L.); (W.W.)
| | - Wen Wen
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (H.L.); (W.W.)
| | - Jia Luo
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (H.L.); (W.W.)
- Iowa City VA Health Care System, Iowa City, IA 52246, USA
- Correspondence: ; Tel.: +1-319-335-2256
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3
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Cooley MM, Thomas DDH, Deans K, Peng Y, Lugea A, Pandol SJ, Puglielli L, Groblewski GE. Deficient Endoplasmic Reticulum Acetyl-CoA Import in Pancreatic Acinar Cells Leads to Chronic Pancreatitis. Cell Mol Gastroenterol Hepatol 2020; 11:725-738. [PMID: 33080365 PMCID: PMC7841443 DOI: 10.1016/j.jcmgh.2020.10.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 10/14/2020] [Accepted: 10/05/2020] [Indexed: 12/17/2022]
Abstract
BACKGROUND & AIMS Maintaining endoplasmic reticulum (ER) proteostasis is essential for pancreatic acinar cell function. Under conditions of severe ER stress, activation of pathogenic unfolded protein response pathways plays a central role in the development and progression of pancreatitis. Less is known, however, of the consequence of perturbing ER-associated post-translational protein modifications on pancreatic outcomes. Here, we examined the role of the ER acetyl-CoA transporter AT-1 on pancreatic homeostasis. METHODS We used an AT-1S113R/+ hypomorphic mouse model, and generated an inducible, acinar-specific, AT-1 knockout mouse model, and performed histologic and biochemical analyses to probe the effect of AT-1 loss on acinar cell physiology. RESULTS We found that AT-1 expression is down-regulated significantly during both acute and chronic pancreatitis. Furthermore, acinar-specific deletion of AT-1 in acinar cells induces chronic ER stress marked by activation of both the spliced x-box binding protein 1 and protein kinase R-like ER kinase pathways, leading to spontaneous mild/moderate chronic pancreatitis evidenced by accumulation of intracellular trypsin, immune cell infiltration, and fibrosis. Induction of acute-on-chronic pancreatitis in the AT-1 model led to acinar cell loss and glad atrophy. CONCLUSIONS These results indicate a key role for AT-1 in pancreatic acinar cell homeostasis, the unfolded protein response, and that perturbations in AT-1 function leads to pancreatic disease.
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Affiliation(s)
| | | | | | - Yajing Peng
- Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Aurelia Lugea
- Pancreatic Research Group, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California
| | - Stephen J Pandol
- Pancreatic Research Group, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California
| | - Luigi Puglielli
- Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin; Geriatric Research Education Clinical Center, Veterans Affairs Medical Center, Madison, Wisconsin
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4
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Ren Y, Qiu M, Zhang J, Bi J, Wang M, Hu L, Du Z, Li T, Zhang L, Wang Y, Lv Y, Wu Z, Wu R. Low Serum Irisin Concentration Is Associated with Poor Outcomes in Patients with Acute Pancreatitis, and Irisin Administration Protects Against Experimental Acute Pancreatitis. Antioxid Redox Signal 2019; 31:771-785. [PMID: 31250660 DOI: 10.1089/ars.2019.7731] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Aims: Severe acute pancreatitis (AP) is a serious condition without specific treatment. Mitochondrial dysfunction plays a crucial role in the pathogenesis of AP. Irisin, a novel exercise-induced hormone, contributes to many health benefits of physical activity. We and others have shown that irisin protects against ischemia reperfusion-induced organ injury by alleviating mitochondrial damage. However, the role of irisin in AP has not been evaluated. The purpose of this study was to investigate the role of serum irisin levels in patients with AP and the effect of irisin administration in experimental AP. Results: Serum irisin levels were decreased in AP patients, and low serum irisin levels were associated with worse outcomes in these patients. Treatment with exogenous irisin increased survival and mitigated pancreatic injury in experimental AP. The protective effects of irisin in AP were associated with improvement in mitochondrial function and reduction in ER stress. Moreover, irisin upregulated UCP2 expression in the pancreas, and administration of genipin, a specific UCP2 antagonist, abolished irisin's beneficial effects in L-arginine-induced AP. Innovation and Conclusion: Low serum irisin was associated with poor outcomes in AP patients, and irisin administration protected against experimental AP by restoring mitochondrial function via activation of UCP2. Restoration of mitochondrial function by irisin may offer therapeutic potential for patients with AP. Antioxid. Redox Signal. 31, 771-785.
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Affiliation(s)
- Yifan Ren
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Minglong Qiu
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Jia Zhang
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Jianbin Bi
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Mengzhou Wang
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Liangshuo Hu
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Zhaoqing Du
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Teng Li
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Lin Zhang
- Department of Laboratory Medicine, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Yawen Wang
- Department of Laboratory Medicine, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Yi Lv
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Zheng Wu
- Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Rongqian Wu
- National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
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5
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Oleic acid ameliorates palmitic acid-induced ER stress and inflammation markers in naive and cerulein-treated exocrine pancreas cells. Biosci Rep 2019; 39:BSR20190054. [PMID: 30992393 PMCID: PMC6522823 DOI: 10.1042/bsr20190054] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 04/06/2019] [Accepted: 04/12/2019] [Indexed: 12/13/2022] Open
Abstract
Dietary fat overload (typical to obesity) increases the risk of pancreatic pathologies through mechanisms yet to be defined. We previously showed that saturated dietary fat induces pancreatic acinar lipotoxicity and cellular stress. The endoplasmic reticulum (ER) of exocrine pancreas cells is highly developed and thus predisposed to stress. We studied the combination of saturated and unsaturated FAs in metabolic and pancreatitis like cerulein (CER)-induced stress states on cellular ER stress. Exocrine pancreas AR42J and rat primary exocrine acinar cells underwent acute (24 h) challenge with different FAs (saturated, monounsaturated) at different concentrations (250 and 500 µM) and in combination with acute CER-induced stress, and were analyzed for fat accumulation, ER stress unfolded protein response (UPR) and immune and enzyme markers. Acute exposure of AR42J and pancreatic acinar cells to different FAs and their combinations increased triglyceride accumulation. Palmitic acid significantly dose-dependently enhanced the UPR, immune factors and pancreatic lipase (PL) levels, as demonstrated by XBP1 splicing and elevation in UPR transcripts and protein levels (Xbp1,Atf6, Atf4, Chop, Tnfα, Tgfβ and Il-6). Exposure to high palmitic levels in a CER-induced stress state synergistically increased ER stress and inflammation marker levels. Exposure to oleic acid did not induce ER stress and PL levels and significantly decreased immune factors in an acute CER-induced stress state. Combination of oleic and palmitic acids significantly reduced the palmitic-induced ER stress, but did not affect the immune factor response. We show that combination of monounsaturated and saturated FAs protects from exocrine pancreatic cellular ER stress in both metabolic and CER-induced stress.
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6
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Ye R, Onodera T, Blanchard PG, Kusminski CM, Esser V, Brekken RA, Scherer PE. β1 Syntrophin Supports Autophagy Initiation and Protects against Cerulein-Induced Acute Pancreatitis. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:813-825. [PMID: 30653956 DOI: 10.1016/j.ajpath.2019.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 12/26/2018] [Accepted: 01/02/2019] [Indexed: 01/23/2023]
Abstract
Syntrophins are a family of proteins forming membrane-anchored scaffolds and serving as adaptors for various transmembrane and intracellular signaling molecules. To understand the physiological roles of β1 syntrophin, one of the least characterized members, we generated mouse models to eliminate β1 syntrophin specifically in the endocrine or exocrine pancreas. β1 syntrophin is dispensable for the morphology and function of insulin-producing β cells. However, mice with β1 syntrophin deletion in exocrine acinar cells exhibit increased severity of cerulein-induced acute pancreatitis. Reduced expression of cystic fibrosis transmembrane conductance regulator and dilation of acinar lumen are potential predisposition factors. During the disease progression, a relative lack of autophagy is associated with deficiencies in both actin assembly and endoplasmic reticulum nucleation. Our findings reveal, for the first time, that β1 syntrophin is a critical regulator of actin cytoskeleton and autophagy in pancreatic acinar cells and is potently protective against cerulein-induced acute pancreatitis.
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Affiliation(s)
- Risheng Ye
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas; Department of Medical Education, Texas Tech University Health Sciences Center Paul L. Foster School of Medicine, El Paso, Texas
| | - Toshiharu Onodera
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Pierre-Gilles Blanchard
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Christine M Kusminski
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Victoria Esser
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Rolf A Brekken
- Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, Texas; Department of Surgery, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas.
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7
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van Lidth de Jeude JF, Spaan CN, Meijer BJ, Smit WL, Soeratram TTD, Wielenga MCB, Westendorp BF, Lee AS, Meisner S, Vermeulen JLM, Wildenberg ME, van den Brink GR, Muncan V, Heijmans J. Heterozygosity of Chaperone Grp78 Reduces Intestinal Stem Cell Regeneration Potential and Protects against Adenoma Formation. Cancer Res 2018; 78:6098-6106. [PMID: 30232220 DOI: 10.1158/0008-5472.can-17-3600] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 05/17/2018] [Accepted: 09/05/2018] [Indexed: 02/05/2023]
Abstract
Deletion of endoplasmic reticulum resident chaperone Grp78 results in activation of the unfolded protein response and causes rapid depletion of the entire intestinal epithelium. Whether modest reduction of Grp78 may affect stem cell fate without compromising intestinal integrity remains unknown. Here, we employ a model of epithelial-specific, heterozygous Grp78 deletion by use of VillinCreERT2-Rosa26ZsGreen/LacZ-Grp78+/fl mice and organoids. We examine models of irradiation and tumorigenesis, both in vitro and in vivo Although we observed no phenotypic changes in Grp78 heterozygous mice, Grp78 heterozygous organoid growth was markedly reduced. Irradiation of Grp78 heterozygous mice resulted in less frequent regeneration of crypts compared with nonrecombined (wild-type) mice, exposing reduced capacity for self-renewal upon genotoxic insult. We crossed mice to Apc-mutant animals for adenoma studies and found that adenomagenesis in Apc heterozygous-Grp78 heterozygous mice was reduced compared with Apc heterozygous controls (1.43 vs. 3.33; P < 0.01). In conclusion, epithelium-specific Grp78 heterozygosity compromises epithelial fitness under conditions requiring expansive growth such as adenomagenesis or regeneration after γ-irradiation. These results suggest that Grp78 may be a therapeutic target in prevention of intestinal neoplasms without affecting normal tissue.Significance: Heterozygous disruption of chaperone protein Grp78 reduces tissue regeneration and expansive growth and protects from tumor formation without affecting intestinal homeostasis. Cancer Res; 78(21); 6098-106. ©2018 AACR.
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Affiliation(s)
- Jooske F van Lidth de Jeude
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Claudia N Spaan
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Bartolomeus J Meijer
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Wouter L Smit
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Tanya T D Soeratram
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Mattheus C B Wielenga
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - B Florien Westendorp
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Amy S Lee
- Department of Biochemistry and Molecular Medicine, USC/Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, California
| | - Sander Meisner
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Jacqueline L M Vermeulen
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Manon E Wildenberg
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Gijs R van den Brink
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Vanesa Muncan
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands
| | - Jarom Heijmans
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, University of Amsterdam, Amsterdam, the Netherlands. .,Department of Internal Medicine, University of Amsterdam, Amsterdam, the Netherlands
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8
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Zhao Y, Xiong RP, Chen X, Li P, Ning YL, Yang N, Peng Y, Jiang YL, Zhou YG. Hsp90 regulation affects the treatment of glucocorticoid for pancreatitis-induced lung injury. Mol Cell Biochem 2017; 440:189-197. [PMID: 28828564 DOI: 10.1007/s11010-017-3166-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/16/2017] [Indexed: 12/19/2022]
Abstract
Glucocorticoids are commonly used for the treatment of pancreatitis and complicated acute lung injury and help to reduce the mortality rates of both. The effect of gene variants in heat shock protein 90 (Hsp90), a key chaperone molecule of the glucocorticoid receptor (GR), on the therapeutic effect of glucocorticoids is unclear. Our study aims to investigate the different susceptibility to glucocorticoid treatment in BALB/c and C57BL/6 mice carrying different Hsp90 genotypes in an animal model of pancreatitis-induced lung injury. Compared with BALB/c mice, C57BL/6 mice have lower mortality rates, decreased water content in their lungs, and a lower level of IL-1 beta in an animal model of acute pancreatitis. C57BL/6 mice show a greater therapeutic effect and increased GR binding activities with glucocorticoid responsive element compared to BALB/c mice after a 0.4 mg/kg dexamethasone (DEX) treatment. Treatment with a higher dose of DEX (4 mg/kg) significantly reduced mortality rates and increased GR-GRE binding activity in both strains of mice, and there was no significant difference between the two strains. DEX did not exert a protective role after geldanamycin, a specific inhibitor of Hsp90, was administered in both strains of mice. Our study revealed that Hsp90 gene variants are responsible for the greater therapeutic effect of DEX in C57BL/6 mice compared to BALB/c mice, which implies that combining DEX treatment with Hsp90 regulation would promote the efficiency of DEX and would be an effective way to alleviate the side effects of hormone therapy.
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Affiliation(s)
- Yan Zhao
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China
| | - Ren-Ping Xiong
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China
| | - Xing Chen
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China
| | - Ping Li
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China
| | - Ya-Lei Ning
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China
| | - Nan Yang
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China
| | - Yan Peng
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China
| | - Yu-Lin Jiang
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China
| | - Yuan-Guo Zhou
- Molecular Biology Center, The State Key Laboratory of Trauma, Burn and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, 10 Changjiang Zhilu, Chongqing, 400042, China.
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9
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Flodby P, Li C, Liu Y, Wang H, Marconett CN, Laird-Offringa IA, Minoo P, Lee AS, Zhou B. The 78-kD Glucose-Regulated Protein Regulates Endoplasmic Reticulum Homeostasis and Distal Epithelial Cell Survival during Lung Development. Am J Respir Cell Mol Biol 2017; 55:135-49. [PMID: 26816051 DOI: 10.1165/rcmb.2015-0327oc] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Bronchopulmonary dysplasia (BPD), a chronic lung disease of prematurity, has been linked to endoplasmic reticulum (ER) stress. To investigate a causal role for ER stress in BPD pathogenesis, we generated conditional knockout (KO) mice (cGrp78(f/f)) with lung epithelial cell-specific KO of Grp78, a gene encoding the ER chaperone 78-kD glucose-regulated protein (GRP78), a master regulator of ER homeostasis and the unfolded protein response (UPR). Lung epithelial-specific Grp78 KO disrupted lung morphogenesis, causing developmental arrest, increased alveolar epithelial type II cell apoptosis, and decreased surfactant protein and type I cell marker expression in perinatal lungs. cGrp78(f/f) pups died immediately after birth, likely owing to respiratory distress. Importantly, Grp78 KO triggered UPR activation with marked induction of the proapoptotic transcription factor CCAAT/enhancer-binding proteins (C/EBP) homologous protein (CHOP). Increased expression of genes involved in oxidative stress and cell death and decreased expression of genes encoding antioxidant enzymes suggest a role for oxidative stress in alveolar epithelial cell (AEC) apoptosis. Increased Smad3 phosphorylation and expression of transforming growth factor-β/Smad3 targets Cdkn1a (encoding p21) and Gadd45a suggest that interactions among the apoptotic arm of the UPR, oxidative stress, and transforming growth factor-β/Smad signaling pathways contribute to Grp78 KO-induced AEC apoptosis and developmental arrest. Chemical chaperone Tauroursodeoxycholic acid reduced UPR activation and apoptosis in cGrp78(f/f) lungs cultured ex vivo, confirming a role for ER stress in observed AEC abnormalities. These results demonstrate a key role for GRP78 in AEC survival and gene expression during lung development through modulation of ER stress, and suggest the UPR as a potential therapeutic target in BPD.
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Affiliation(s)
- Per Flodby
- Departments of 1 Medicine, Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care and Sleep Medicine
| | | | - Yixin Liu
- Departments of 1 Medicine, Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care and Sleep Medicine
| | - Hongjun Wang
- Departments of 1 Medicine, Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care and Sleep Medicine
| | - Crystal N Marconett
- 3 Surgery, and.,4 Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, California
| | - Ite A Laird-Offringa
- 3 Surgery, and.,5 Biochemistry and Molecular Biology, and.,4 Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, California
| | | | - Amy S Lee
- 5 Biochemistry and Molecular Biology, and.,4 Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, California
| | - Beiyun Zhou
- Departments of 1 Medicine, Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care and Sleep Medicine.,4 Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, California
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10
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GRP78 haploinsufficiency suppresses acinar-to-ductal metaplasia, signaling, and mutant Kras-driven pancreatic tumorigenesis in mice. Proc Natl Acad Sci U S A 2017; 114:E4020-E4029. [PMID: 28461470 DOI: 10.1073/pnas.1616060114] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal disease in critical need of new therapeutic strategies. Here, we report that the stress-inducible 78-kDa glucose-regulated protein (GRP78/HSPA5), a key regulator of endoplasmic reticulum homeostasis and PI3K/AKT signaling, is overexpressed in the acini and PDAC of Pdx1-Cre;KrasG12D/+;p53f/+ (PKC) mice as early as 2 mo, suggesting that GRP78 could exert a protective effect on acinar cells under stress, as during PDAC development. The PKC pancreata bearing wild-type Grp78 showed detectable PDAC by 3 mo and rapid subsequent tumor growth. In contrast, the PKC pancreata bearing a Grp78f/+ allele (PKC78f/+ mice) expressing about 50% of GRP78 maintained normal sizes during the early months, with reduced proliferation and suppression of AKT, S6, ERK, and STAT3 activation. Acinar-to-ductal metaplasia (ADM) has been identified as a key tumor initiation mechanism of PDAC. Compared with PKC, the PKC78f/+ pancreata showed substantial reduction of ADM as well as pancreatic intraepithelial neoplasia-1 (PanIN-1), PanIN-2, and PanIN-3 and delayed onset of PDAC. ADM in response to transforming growth factor α was also suppressed in ex vivo cultures of acinar cell clusters isolated from mouse pancreas bearing targeted heterozygous knockout of Grp78 (c78f/+ ) and subjected to 3D culture in collagen. We further discovered that GRP78 haploinsufficiency in both the PKC78f/+ and c78f/+ pancreata leads to reduction of epidermal growth factor receptor, which is critical for ADM initiation. Collectively, our studies establish a role for GRP78 in ADM and PDAC development.
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11
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Lee AS, Brandhorst S, Rangel DF, Navarrete G, Cohen P, Longo VD, Chen J, Groshen S, Morgan TE, Dubeau L. Effects of Prolonged GRP78 Haploinsufficiency on Organ Homeostasis, Behavior, Cancer and Chemotoxic Resistance in Aged Mice. Sci Rep 2017; 7:40919. [PMID: 28145503 PMCID: PMC5286507 DOI: 10.1038/srep40919] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 12/13/2016] [Indexed: 01/01/2023] Open
Abstract
GRP78, a multifunctional protein with potent cytoprotective properties, is an emerging therapeutic target to combat cancer development, progression and drug resistance. The biological consequences of prolonged reduction in expression of this essential chaperone which so far has been studied primarily in young mice, was investigated in older mice, as older individuals are likely to be important recipients of anti-GRP78 therapy. We followed cohorts of Grp78+/+ and Grp78+/- male and female mice up to 2 years of age in three different genetic backgrounds and characterized them with respect to body weight, organ integrity, behavioral and memory performance, cancer, inflammation and chemotoxic response. Our results reveal that body weight, organ development and integrity were not impaired in aged Grp78+/- mice. No significant effect on cancer incidence and inflammation was observed in aging mice. Interestingly, our studies detected some subtle differential trends between the WT and Grp78+/- mice in some test parameters dependent on gender and genetic background. Our studies provide the first evidence that GRP78 haploinsufficiency for up to 2 years of age has no major deleterious effect in rodents of different genetic background, supporting the merit of anti-GRP78 drugs in treatment of cancer and other diseases affecting the elderly.
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Affiliation(s)
- Amy S. Lee
- Department of Biochemistry and Molecular Biology, University of Southern California Keck School of Medicine, USC Norris Comprehensive Cancer Center, 1441 Eastlake Avenue, Los Angeles, CA 90089-9176, United States
| | - Sebastian Brandhorst
- Longevity Institute, Leonard Davis School of Gerontology and Department of Biological Sciences, University of Southern California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, United States
| | - Daisy F. Rangel
- Department of Biochemistry and Molecular Biology, University of Southern California Keck School of Medicine, USC Norris Comprehensive Cancer Center, 1441 Eastlake Avenue, Los Angeles, CA 90089-9176, United States
| | - Gerardo Navarrete
- Longevity Institute, Leonard Davis School of Gerontology and Department of Biological Sciences, University of Southern California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, United States
| | - Pinchas Cohen
- Longevity Institute, Leonard Davis School of Gerontology and Department of Biological Sciences, University of Southern California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, United States
| | - Valter D. Longo
- Longevity Institute, Leonard Davis School of Gerontology and Department of Biological Sciences, University of Southern California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, United States
| | - Jeannie Chen
- Zilkha Neurogenetic Institute, Department of Cell and Neurobiology & Department of Ophthalmology, University of Southern California Keck School of Medicine, 1501 San Pablo Street, Los Angeles, CA 90033, United States
| | - Susan Groshen
- Department of Preventive Medicine, University of Southern California Keck School of Medicine, 1441 Eastlake Avenue, Los Angeles, CA 90033, United States
| | - Todd E. Morgan
- Longevity Institute, Leonard Davis School of Gerontology and Department of Biological Sciences, University of Southern California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, United States
| | - Louis Dubeau
- Department of Pathology, University of Southern California Keck School of Medicine, USC Norris Comprehensive Cancer Center, 1441 Eastlake Avenue, Los Angeles, CA 90089-9176, United States
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12
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Matsukuma S, Yoshimura K, Ueno T, Oga A, Inoue M, Watanabe Y, Kuramasu A, Fuse M, Tsunedomi R, Nagaoka S, Eguchi H, Matsui H, Shindo Y, Maeda N, Tokuhisa Y, Kawano R, Furuya-Kondo T, Itoh H, Yoshino S, Hazama S, Oka M, Nagano H. Calreticulin is highly expressed in pancreatic cancer stem-like cells. Cancer Sci 2016; 107:1599-1609. [PMID: 27561105 PMCID: PMC5132278 DOI: 10.1111/cas.13061] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 08/05/2016] [Accepted: 08/14/2016] [Indexed: 12/22/2022] Open
Abstract
Cancer stem‐like cells (CSLCs) in solid tumors are thought to be resistant to conventional chemotherapy or molecular targeting therapy and to contribute to cancer recurrence and metastasis. In this study, we aimed to identify a biomarker of pancreatic CSLCs (P‐CSLCs). A P‐CSLC‐enriched population was generated from pancreatic cancer cell lines using our previously reported method and its protein expression profile was compared with that of parental cells by 2‐D electrophoresis and tandem mass spectrometry. The results indicated that a chaperone protein calreticulin (CRT) was significantly upregulated in P‐CSLCs compared to parental cells. Flow cytometry analysis indicated that CRT was mostly localized to the surface of P‐CSLCs and did not correlate with the levels of CD44v9, another P‐CSLC biomarker. Furthermore, the side population in the CRThigh/CD44v9low population was much higher than that in the CRTlow/CD44v9high population. Calreticulin expression was also assessed by immunohistochemistry in pancreatic cancer tissues (n = 80) obtained after radical resection and was found to be associated with patients' clinicopathological features and disease outcomes in the Cox proportional hazard regression model. Multivariate analysis identified CRT as an independent prognostic factor for pancreatic cancer patients, along with age and postoperative therapy. Our results suggest that CRT can serve as a biomarker of P‐CSLCs and a prognostic factor associated with poorer survival of pancreatic cancer patients. This novel biomarker can be considered as a therapeutic target for cancer immunotherapy.
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Affiliation(s)
- Satoshi Matsukuma
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Kiyoshi Yoshimura
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.,Exploratory Oncology Research and Clinical Trial Center, National Cancer Center of Japan, Tokyo, Japan
| | - Tomio Ueno
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Atsunori Oga
- Department of Molecular Pathology, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Moeko Inoue
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.,Exploratory Oncology Research and Clinical Trial Center, National Cancer Center of Japan, Tokyo, Japan
| | - Yusaku Watanabe
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Atsuo Kuramasu
- Department of Molecular Pharmacology, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Masanori Fuse
- Exploratory Oncology Research and Clinical Trial Center, National Cancer Center of Japan, Tokyo, Japan
| | - Ryouichi Tsunedomi
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Satoshi Nagaoka
- Department of Gastroenterological Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Hidetoshi Eguchi
- Department of Gastroenterological Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Hiroto Matsui
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Yoshitaro Shindo
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Noriko Maeda
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Yoshihiro Tokuhisa
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Reo Kawano
- Center for Clinical Research, Yamaguchi University Hospital, Ube, Japan
| | - Tomoko Furuya-Kondo
- Department of Molecular Pathology, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Hiroshi Itoh
- Department of Molecular Pathology, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Shigefumi Yoshino
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.,Oncology Center, Yamaguchi University Hospital, Ube, Japan
| | - Shoichi Hazama
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.,Department of Translational Research and Developmental Therapeutics against Cancer, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Masaaki Oka
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Hiroaki Nagano
- Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan
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13
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Pathophysiological mechanisms in acute pancreatitis: Current understanding. Indian J Gastroenterol 2016; 35:153-66. [PMID: 27206712 DOI: 10.1007/s12664-016-0647-y] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 03/16/2016] [Indexed: 02/04/2023]
Abstract
The precise mechanisms involved in the pathophysiology of acute pancreatitis (AP) are still far from clear. Several earlier studies have focused mainly on pancreatic enzyme activation as the key intracellular perturbation in the pancreatic acinar cells. For decades, the trypsin-centered hypothesis has remained the focus of the intra-acinar events in acute pancreatitis. Recent advances in basic science research have lead to the better understanding of various other mechanisms such as oxidative and endoplasmic stress, impaired autophagy, mitochondrial dysfunction, etc. in causing acinar cell injury. Despite all efforts, the clinical outcome of patients with AP has not changed significantly over the years. This suggests that the knowledge of the critical molecular pathways in the pathophysiology of AP is still limited. The mechanisms through which the acinar cell injury leads to local and systemic inflammation are not well understood. The role of inflammatory markers and immune system activation is an area of much relevance from the point of view of finding a target for therapeutic intervention. Some data are available from experimental animal models but not much is known in human pancreatitis. This review intends to highlight the current understanding in this area.
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14
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Danino H, Ben-Dror K, Birk R. Exocrine pancreas ER stress is differentially induced by different fatty acids. Exp Cell Res 2015; 339:397-406. [DOI: 10.1016/j.yexcr.2015.09.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Revised: 09/26/2015] [Accepted: 09/29/2015] [Indexed: 12/13/2022]
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15
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Zhu G, Lee AS. Role of the unfolded protein response, GRP78 and GRP94 in organ homeostasis. J Cell Physiol 2015; 230:1413-20. [PMID: 25546813 DOI: 10.1002/jcp.24923] [Citation(s) in RCA: 215] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 12/19/2014] [Indexed: 02/06/2023]
Abstract
The endoplasmic reticulum (ER) is a cellular organelle where secretory and membrane proteins, as well as lipids, are synthesized and modified. When cells are subjected to ER stress, an adaptive mechanism referred to as the Unfolded Protein Response (UPR) is triggered to allow the cells to restore homeostasis. Evidence has accumulated that the UPR pathways provide specialized and unique roles in diverse development and metabolic processes. The glucose regulated proteins (GRPs) are traditionally regarded as ER proteins with chaperone and calcium binding properties. The GRPs are constitutively expressed at basal levels in all organs, and as stress-inducible ER chaperones, they are major players in protein folding, assembly and degradation. This conventional concept is augmented by recent discoveries that GRPs can be actively translocated to other cellular locations such as the cell surface, where they assume novel functions that regulate signaling, proliferation, apoptosis and immunity. Recent construction and characterization of mouse models where the gene encoding for the UPR components and the GRPs is genetically altered provide new insights on the physiological contribution of these proteins in vivo. This review highlights recent progress towards the understanding of the role of the UPR and two major GRPs (GRP78 and GRP94) in regulating homeostasis of organs arising from the endoderm, mesoderm and ectoderm. GRP78 and GRP94 exhibit shared and unique functions, and in specific organs their depletion elicits adaptive responses with physiological consequences.
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Affiliation(s)
- Genyuan Zhu
- Department of Biochemistry and Molecular Biology, USC Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California
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16
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Zhao HX, Fu XS, Zhou XY, Chen X. Endoplasmic reticulum stress may not be involved in intestinal epithelial cell apoptosis in experimental acute pancreatitis. Dig Dis Sci 2015; 60:1690-8. [PMID: 25616612 DOI: 10.1007/s10620-015-3542-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Accepted: 01/14/2015] [Indexed: 12/23/2022]
Abstract
OBJECTIVES To investigate whether endoplasmic reticulum (ER) stress is activated in the intestinal epithelium of acute pancreatitis (AP), and whether it is one of the inducing factors of the intestinal epithelial cell apoptosis in AP. METHODS Twenty-four rats were randomly divided into two groups. AP was induced via retrograde injection of 3 % sodium taurocholate into the pancreatic duct. As a control group, rats received a sham operation. Forty-eight hours after the operation, the ultrastructural changes of ileal epithelial cells were investigated by transmission electron microscope. The protein expressions of GRP78, CHOP, caspase-12, and JNK in the ileal epithelium were determined by immunohistochemistry, and apoptosis was determined by TdT-mediated dUTP nick end labeling. The mRNA expressions of GRP78, CHOP, caspase-12, and JNK in the ileal epithelium were determined using quantitative RT-PCR. RESULTS The ileal epithelium in rats with AP had significantly higher apoptotic cells compared with that of the control rats (P < 0.05). ER stress was activated in the ileal epithelium, which was characterized by dilated, irregular ER and upregulated expressions of GRP78 mRNA and protein. The mRNA and protein expressions of CHOP, caspase-12, and JNK in rats with AP were similar to that in the control rats (P > 0.05). CONCLUSIONS ER stress is induced in intestinal epithelium during AP; however, ER stress is not likely to be involved in the apoptosis of the intestinal epithelium during AP.
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Affiliation(s)
- Hong-Xian Zhao
- Department of Histology and Embryology, Luzhou Medical College, Luzhou City, 646000, People's Republic of China
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17
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Ye R, Holland WL, Gordillo R, Wang M, Wang QA, Shao M, Morley TS, Gupta RK, Stahl A, Scherer PE. Adiponectin is essential for lipid homeostasis and survival under insulin deficiency and promotes β-cell regeneration. eLife 2014; 3. [PMID: 25339419 PMCID: PMC4228265 DOI: 10.7554/elife.03851] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 10/15/2014] [Indexed: 01/03/2023] Open
Abstract
As an adipokine in circulation, adiponectin has been extensively studied for its beneficial metabolic effects. While many important functions have been attributed to adiponectin under high-fat diet conditions, little is known about its essential role under regular chow. Employing a mouse model with inducible, acute β-cell ablation, we uncovered an essential role of adiponectin under insulinopenic conditions to maintain minimal lipid homeostasis. When insulin levels are marginal, adiponectin is critical for insulin signaling, endocytosis, and lipid uptake in subcutaneous white adipose tissue. In the absence of both insulin and adiponectin, severe lipoatrophy and hyperlipidemia lead to lethality. In contrast, elevated adiponectin levels improve systemic lipid metabolism in the near absence of insulin. Moreover, adiponectin is sufficient to mitigate local lipotoxicity in pancreatic islets, and it promotes reconstitution of β-cell mass, eventually reinstating glycemic control. We uncovered an essential new role for adiponectin, with major implications for type 1 diabetes. DOI:http://dx.doi.org/10.7554/eLife.03851.001 Fat tissue is essential for health. Fat cells store energy and release it when it is needed; they also release hormones that are important for the health of our heart and for regulating our metabolism. One of these hormones, adiponectin, helps cells to remove fat molecules from the bloodstream. This allows the body to maintain appropriate cholesterol levels and prevents fatty build-ups from blocking blood vessels, which is associated with heart disease. Adiponectin also helps cells respond to insulin, a hormone that regulates blood sugar levels, and thus helps to prevent diabetes. Despite this hormone's important roles in health, mice that lack adiponectin can thrive under normal conditions. Adiponectin becomes essential, however, when blood sugar or fat levels are considerably altered. For example, when mice without adiponectin are fed a high fat-content diet, they become insulin-resistant. Moreover, certain diabetes drugs that boost insulin sensitivity only work if adiponectin is present in the body. Adiponectin helps to keep the β-cells that produce insulin alive. In patients with diabetes, β-cells slowly die, and this leads to a poor insulin response and an imbalance in the amount of fats and sugars in the cells. This is toxic to the β-cells; and as more β-cells die, less insulin is produced to control sugar levels, and the condition worsens. Adiponectin appears to protect the β-cells against this vicious cycle, but the details of how it does so are unclear. Ye et al. used a mouse model in which β-cells were destroyed to see what adiponectin does when insulin is in short supply. When insulin levels were extremely low, adiponectin was found to help one type of fat tissue absorb fat molecules from the bloodstream, which reduced blood cholesterol levels. It also protects fat cells from being destroyed when insulin levels are low. Ye et al. also found that mice that lack both insulin and adiponectin lose excessive amounts of fat tissue and develop high blood cholesterol levels, which lead to death. Increasing adiponectin levels in insulin-deficient mice, however, improves their blood cholesterol levels and protects β-cells from being destroyed. This allows the β-cells to begin regenerating. As the β-cells regenerate, the insulin-deficient mice developed better control over their blood sugar. Many people with type-1 diabetes (which is caused by their own immune system destroying their β-cells) currently rely on insulin injections and restricted diets to manage their condition. Ye et al.'s findings might lead to new strategies to restore β-cell production and blood sugar control; as such these findings will have important implications for the management of type-1 diabetes. DOI:http://dx.doi.org/10.7554/eLife.03851.002
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Affiliation(s)
- Risheng Ye
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - William L Holland
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Ruth Gordillo
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Miao Wang
- Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, United States
| | - Qiong A Wang
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Mengle Shao
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Thomas S Morley
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Rana K Gupta
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Andreas Stahl
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, United States
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
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18
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Koenig PA, Ploegh HL. Protein quality control in the endoplasmic reticulum. F1000PRIME REPORTS 2014; 6:49. [PMID: 25184039 PMCID: PMC4108957 DOI: 10.12703/p6-49] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
THE TOPOLOGICAL BARRIERS DEFINED BY BIOLOGICAL MEMBRANES ARE NOT IMPERMEABLE: from small solutes to intact proteins, specialized transport and translocation mechanisms adjust to the cell's needs. Here, we review the removal of unwanted proteins from the endoplasmic reticulum (ER) and emphasize the need to extend observations from tissue culture models and simple eukaryotes to studies in whole animals. The variation in protein production and composition that characterizes different cell types and tissues requires tailor-made solutions to exert proper control over both protein synthesis and breakdown. The ER is an organelle essential to achieve and maintain such homeostasis.
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Affiliation(s)
- Paul-Albert Koenig
- Klinikum rechts der Isar, Technische Universität München, Institut für Klinische Chemie und Pathobiochemie, Ismaninger Straße22, 81675 MünchenGermany
| | - Hidde L. Ploegh
- Whitehead Institute for Biomedical Research9 Cambridge Center, Cambridge, 02142 MAUSA
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19
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Wu L, Cai B, Zheng S, Liu X, Cai H, Li H. Effect of emodin on endoplasmic reticulum stress in rats with severe acute pancreatitis. Inflammation 2014; 36:1020-9. [PMID: 23605470 DOI: 10.1007/s10753-013-9634-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This study aimed to investigate the protective effect of emodin on endoplasmic reticulum (ER) stress in rats with severe acute pancreatitis (SAP) and the underlying molecular mechanism. Sprague-Dawley male rats were randomly divided into sham operation group, SAP model group, and emodin treatment group. SAP was constructed through injecting sodium taurocholate into pancreatic and biliary duct in rats. Half an hour before establishing the animal model, emodin or sodium carboxymethylcellulose was intragastrically administrated to the rats in respective group. Rats were killed at 3, 6, and 12 h postdisease induction. The amylase, tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) levels in serum, pancreatic histopathology, acinar ER ultrastructure, protein expression of Bip, IRE1α,TRAF2, ASK1, p-JNK, and p-p38 MAPK in pancreas were examined. Sodium taurocholate induced pancreatic injury and ER lumen dilated in exocrine pancreas in rats at 3-, 6-, and 12-h time points. ER stress transducers Bip, IRE1α, and their downstream molecules TRAF2, ASK1 in pancreatitis were upregulated. Furthermore, phosphorylation of JNK and p38MAPK in pancreas was increased, which induced high expression level of inflammatory cytokines such as TNF-α and IL-6. Treatment with emodin obviously ameliorated pancreatic injury and decreased the release of amylase and inflammatory cytokines. Further studies showed that emodin significantly decreased the expression of Bip, IRE1α, TRAF2, and ASK1, inhibited phosphorylation of JNK and p38 MAPK in pancreas in rats at all time points. Emodin could reduce pancreatic injury and restrain inflammatory reaction in SAP rats partly via inhibiting ER stress transducers IRE1α and its downstream molecules.
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Affiliation(s)
- Li Wu
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, People's Republic of China
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20
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Expression of GRP78 predicts taxane-based therapeutic resistance and recurrence of human gastric cancer. Exp Mol Pathol 2014; 96:235-41. [DOI: 10.1016/j.yexmp.2014.02.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 02/19/2014] [Accepted: 02/24/2014] [Indexed: 11/17/2022]
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21
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Weng TI, Wu HY, Chen BL, Jhuang JY, Huang KH, Chiang CK, Liu SH. C/EBP homologous protein deficiency aggravates acute pancreatitis and associated lung injury. World J Gastroenterol 2013; 19:7097-7105. [PMID: 24222953 PMCID: PMC3819545 DOI: 10.3748/wjg.v19.i41.7097] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/17/2013] [Accepted: 08/20/2013] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the pathophysiological role of C/EBP homologous protein (CHOP) in severe acute pancreatitis and associated lung injury.
METHODS: A severe acute pancreatitis model was induced with 6 injections of cerulein (Cn, 50 μg/kg) at 1-h intervals, then intraperitoneal injection of lipopolysaccharide (LPS, 7.5 mg/kg) in CHOP-deficient (Chop-/-) mice and wild-type (WT) mice. Animals were sacrificed under anesthesia, 3 h or 18 h after LPS injection. Serum amylase, lipase, and cytokines [interleukin (IL)-6 and tumor necrosis factor (TNF)-α], pathological changes, acute lung injury, and apoptosis in the pancreas were evaluated. Serum amylase and lipase activities were detected using a medical automatic chemical analyzer. Enzyme-linked immunosorbent assay kits were used to evaluate TNF-α and IL-6 levels in mouse serum and lung tissue homogenates. Apoptotic cells in sections of pancreatic tissues were determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) analysis. The mouse carotid arteries were cannulated and arterial blood samples were collected for PaO2 analysis. The oxygenation index was expressed as PaO2/FiO2.
RESULTS: Administration of Cn and LPS for 9 and 24 h induced severe acute pancreatitis in Chop-/- and WT mice. When comparing Chop-/- mice and WT mice, we observed that CHOP-deficient mice had greater increases in serum TNF-α (214.40 ± 19.52 pg/mL vs 150.40 ± 16.70 pg/mL; P = 0.037), amylase (4236.40 ± 646.32 U/L vs 2535.30 ± 81.83 U/L; P = 0.041), lipase (1678.20 ± 170.57 U/L vs 1046.21 ± 35.37 U/L; P = 0.008), and IL-6 (2054.44 ± 293.81 pg/mL vs 1316.10 ± 108.74 pg/mL; P = 0.046) than WT mice. The histopathological changes in the pancreases and lungs, decreased PaO2/FiO2 ratio, and increased TNF-α and IL-6 levels in the lungs were greater in Chop-/- mice than in WT mice (pancreas: Chop-/-vs WT mice, hemorrhage, P = 0.005; edema, P = 0.005; inflammatory cells infiltration, P = 0.005; total scores, P = 0.006; lung: hemorrhage, P = 0.017; edema, P = 0.017; congestion, P = 0.017; neutrophil infiltration, P = 0.005, total scores, P = 0.001; PaO2/FiO2 ratio: 393 ± 17.65 vs 453.8, P = 0.041; TNF-α: P = 0.043; IL-6, P = 0.040). Results from TUNEL analysis indicated increased acinar cell apoptosis in mice following the induction of acute pancreatitis. However, Chop-/- mice displayed significantly reduced pancreatic apoptosis compared with the WT mice (201.50 ± 31.43 vs 367.00 ± 47.88, P = 0.016).
CONCLUSION: These results suggest that CHOP can exert protective effects against acute pancreatitis and limit the spread of inflammatory damage to the lungs.
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Wu L, Cai B, Liu X, Cai H. Emodin attenuates calcium overload and endoplasmic reticulum stress in AR42J rat pancreatic acinar cells. Mol Med Rep 2013; 9:267-72. [PMID: 24190079 DOI: 10.3892/mmr.2013.1773] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 10/25/2013] [Indexed: 01/13/2023] Open
Abstract
The aim of the present study was to investigate the protective effects of emodin against calcium overload and endoplasmic reticulum (ER) stress in an acute pancreatitis model in vitro. AR42J rat pancreatic acinar cells treated with cerulein (10(‑7) M) and lipoplysaccharide (LPS; 10 mg/l) were used to mimic acute pancreatitis in vitro. The amylase activity in cellular lysates and culture media was detected by spectrophotometry. The level of cytosolic calcium was measured by laser confocal microscopy. Cell apoptosis and necrosis were examined by flow cytometry. Reverse transcription‑polymerase chain reaction was used to determine the mRNA expression of ER chaperone immunoglobulin‑binding protein (Bip) and downstream molecules, including protein kinase‑like ER kinase (PERK), activation transcription factor 6 (ATF6) and inositol‑requiring protein 1 (IRE1). The results showed that emodin significantly reduced the expression and release of amylase, attenuated calcium overload and decreased the mRNA expression of Bip, PERK, ATF6 and IRE1 which was significantly elevated in AR42J cells treated with cerulein and LPS. Emodin also reduced cell apoptosis and necrosis. Therefore, the results of the present study indicate that emodin protects against AR42J cell injury caused by cerulein and LPS. These effects may be associated with reduced calcium overload and inhibited ER stress responses.
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Affiliation(s)
- Li Wu
- National First-Class Key Discipline for Science of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, P.R. China
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23
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Chen WT, Zhu G, Pfaffenbach K, Kanel G, Stiles B, Lee AS. GRP78 as a regulator of liver steatosis and cancer progression mediated by loss of the tumor suppressor PTEN. Oncogene 2013; 33:4997-5005. [PMID: 24141775 PMCID: PMC3994182 DOI: 10.1038/onc.2013.437] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 08/30/2013] [Accepted: 09/05/2013] [Indexed: 02/06/2023]
Abstract
Glucose-regulated protein 78 (GRP78), a molecular chaperone widely elevated in human cancers, is critical for endoplasmic reticulum (ER) protein folding, stress signaling and PI3K/AKT activation. Genetic knockout models of GRP78 revealed that GRP78 maintains homeostasis of metabolic organs, including liver, pancreas and adipose tissues. Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the most common liver cancers. There is a lack of effective therapeutics for HCC and CC, highlighting the need to further understand liver tumorigenic mechanisms. PTEN, a tumor suppressor that antagonizes the PI3K/AKT pathway, is inactivated in a wide range of tumors, including 40–50% of human liver cancers. To elucidate the role of GRP78 in liver cancer, we created a mouse model with biallelic liver-specific deletion of Pten and Grp78 mediated by Albumin-Cre-recombinase (cPf/f78f/f). Interestingly, in contrast to PTEN, deletion of GRP78 was progressive but incomplete. At 3 months, cPf/f78f/f livers showed hepatomegaly, activation of lipogenic genes, exacerbated steatosis and liver injury, implying that GRP78 protects the liver against PTEN-null mediated pathogenesis. Furthermore, in response to liver injury, we observed increased proliferation and expansion of bile duct and liver progenitor cells in cPf/f78f/f livers. Strikingly, bile duct cells in cPf/f78f/f livers maintained wild-type (WT) GRP78 level while adjacent areas showed GRP78 reduction. Analysis of signaling pathways revealed selective JNK activation, β-catenin downregulation, along with PDGFRα upregulation, which was unique to cPf/f78f/f livers at 6 months. Development of both HCC and CC was accelerated and evident in cPf/f78f/f livers at 8–9 months, coinciding with intense GRP78 expression in the cancer lesions, and GRP78 expression in adjacent normal areas reverted back to the WT level. In contrast, c78f/f livers showed no malignancy even at 14 months. These studies reveal GRP78 is a novel regulator for PTEN-loss mediated liver injury and cancer progression.
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Affiliation(s)
- W-T Chen
- Department of Biochemistry and Molecular Biology, USC Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - G Zhu
- Department of Biochemistry and Molecular Biology, USC Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - K Pfaffenbach
- Department of Biology, Eastern Oregon University, La Grande, OR, USA
| | - G Kanel
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - B Stiles
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, Los Angeles, CA, USA
| | - A S Lee
- Department of Biochemistry and Molecular Biology, USC Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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Li N, Wu X, Holzer RG, Lee JH, Todoric J, Park EJ, Ogata H, Gukovskaya AS, Gukovsky I, Pizzo DP, VandenBerg S, Tarin D, Atay C, Arkan MC, Deerinck TJ, Moscat J, Diaz-Meco M, Dawson D, Erkan M, Kleeff J, Karin M. Loss of acinar cell IKKα triggers spontaneous pancreatitis in mice. J Clin Invest 2013; 123:2231-43. [PMID: 23563314 DOI: 10.1172/jci64498] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 02/14/2013] [Indexed: 12/16/2022] Open
Abstract
Chronic pancreatitis is an inflammatory disease that causes progressive destruction of pancreatic acinar cells and, ultimately, loss of pancreatic function. We investigated the role of IκB kinase α (IKKα) in pancreatic homeostasis. Pancreas-specific ablation of IKKα (Ikkα(Δpan)) caused spontaneous and progressive acinar cell vacuolization and death, interstitial fibrosis, inflammation, and circulatory release of pancreatic enzymes, clinical signs resembling those of human chronic pancreatitis. Loss of pancreatic IKKα causes defective autophagic protein degradation, leading to accumulation of p62-mediated protein aggregates and enhanced oxidative and ER stress in acinar cells, but none of these effects is related to NF-κB. Pancreas-specific p62 ablation prevented ER and oxidative stresses and attenuated pancreatitis in Ikkα(Δpan) mice, suggesting that cellular stress induced by p62 aggregates promotes development of pancreatitis. Importantly, downregulation of IKKα and accumulation of p62 aggregates were also observed in chronic human pancreatitis. Our studies demonstrate that IKKα, which may control autophagic protein degradation through its interaction with ATG16L2, plays a critical role in maintaining pancreatic acinar cell homeostasis, whose dysregulation promotes pancreatitis through p62 aggregate accumulation.
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Affiliation(s)
- Ning Li
- Laboratory of Gene Regulation and Signal Transduction, Departments of Pharmacology and Pathology, School of Medicine, UCSD, La Jolla, California 92093-0723, USA
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25
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The role of the unfolded protein response in diabetes mellitus. Semin Immunopathol 2013; 35:333-50. [PMID: 23529219 DOI: 10.1007/s00281-013-0369-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 03/13/2013] [Indexed: 12/13/2022]
Abstract
The endoplasmic reticulum (ER) plays a key role in the synthesis and modification of secretory and membrane proteins in all eukaryotic cells. Under normal conditions, these proteins are correctly folded and assembled in the ER. However, when cells are exposed to environmental factors such as overproduction of ER proteins, viral infections, or glucose deprivation, the secretory and membrane proteins can accumulate in unfolded or misfolded forms in the lumen of the ER, and consequently, cause stress in the ER. To maintain cellular homeostasis, cells induce several responses to ER stress. In mammalian cells, ER stress responses are induced by a diversity of signal pathways. There are three ER-located transmembrane proteins that play important roles in mammalian ER stress responses: activating transcription factor 6, inositol-requiring protein 1, and protein kinase RNA-like endoplasmic reticulum kinase. ER stress is linked to various diseases, including diabetes. This review highlights the particular importance of ER stress-responsive molecules in insulin biosynthesis, glyconeogenesis, insulin resistance, glucose intolerance, and pancreatic β-cell apoptosis. An understanding of the pathogenic mechanism of diabetes from the aspect of ER stress is crucial in formulating therapeutic strategies.
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26
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Zhu G, Ye R, Jung DY, Barron E, Friedline RH, Benoit VM, Hinton DR, Kim JK, Lee AS. GRP78 plays an essential role in adipogenesis and postnatal growth in mice. FASEB J 2012. [PMID: 23180827 DOI: 10.1096/fj.12-213330] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To investigate the role of GRP78 in adipogenesis and metabolic homeostasis, we knocked down GRP78 in mouse embryonic fibroblasts and 3T3-L1 preadipocytes induced to undergo differentiation into adipocytes. We also created an adipose Grp78-knockout mouse utilizing the aP2 (fatty acid binding protein 4) promoter-driven Cre-recombinase. Adipogenesis was monitored by molecular markers and histology. Tissues were analyzed by micro-CT and electron microscopy. Glucose homeostasis and cytokine analysis were performed. Our results indicate that GRP78 is essential for adipocyte differentiation in vitro. aP2-cre-mediated GRP78 deletion leads to lipoatrophy with ∼90% reduction in gonadal and subcutaneous white adipose tissue and brown adipose tissue, severe growth retardation, and bone defects. Despite severe abnormality in adipose mass and function, adipose Grp78-knockout mice showed normal plasma triglyceride levels, and plasma glucose and insulin levels were reduced by 40-60% compared to wild-type mice, suggesting enhanced insulin sensitivity. The endoplasmic reticulum is grossly expanded in the residual mutant white adipose tissue. Thus, these studies establish that GRP78 is required for adipocyte differentiation, glucose homeostasis, and balanced secretion of adipokines. Unexpectedly, the phenotypes and metabolic parameters of the mutant mice, which showed early postnatal mortality, are uniquely distinct from previously characterized lipodystrophic mouse models.
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Affiliation(s)
- Genyuan Zhu
- Department of Biochemistry and Molecular Biology, USC Norris Comprehensive Cancer Center, 1441 Eastlake Ave., Rm. 5308, Los Angeles, CA 90089-9176, USA
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27
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Abstract
PURPOSE OF REVIEW In this article, recent advances in the pathogenesis of acute pancreatitis have been reviewed. RECENT FINDINGS Pathologic intra-acinar trypsinogen activation had been hypothesized to be the central mechanism of pancreatitis for over a century. This hypothesis could be explored for the first time with the development of a novel mouse model lacking pathologic intra-acinar trypsinogen activation. It became clear that intra-acinar trypsinogen activation contributes to early acinar injury, but local and systemic inflammation progress independently during pancreatitis. Early intra-acinar nuclear factor kappa B (NFκB) activation, which occurs parallel to but independent of trypsinogen activation, may be crucial in pancreatitis. Although the mechanism of NFκB and trypsinogen activation is not entirely clear, further insights have been made into key pathogenic cellular events such as calcium signaling, mitochondrial dysfunction, endoplasmic reticulum (ER) stress, autophagy and impaired trafficking, and lysosomal and secretory responses. Cellular intrinsic damage-sensing mechanisms that lead to activation of the inflammatory response aimed at repair, but lead to disease when overwhelmed, are beginning to be understood. SUMMARY New findings necessitate a paradigm shift in our understanding of acute pancreatitis. Intra-acinar trypsinogen activation leads to early pancreatic injury, but the inflammatory response of acute pancreatitis develops independently, driven by early activation of inflammatory pathways.
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Hill R, Li Y, Tran LM, Dry S, Calvopina JH, Garcia A, Kim C, Wang Y, Donahue TR, Herschman HR, Wu H. Cell intrinsic role of COX-2 in pancreatic cancer development. Mol Cancer Ther 2012; 11:2127-37. [PMID: 22784710 DOI: 10.1158/1535-7163.mct-12-0342] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
COX-2 is upregulated in pancreatic ductal adenocarcinomas (PDAC). However, how COX-2 promotes PDAC development is unclear. While previous studies have evaluated the efficacy of COX-2 inhibition via the use of nonsteroidal anti-inflammatory drugs (NSAID) or the COX-2 inhibitor celecoxib in PDAC models, none have addressed the cell intrinsic versus microenvironment roles of COX-2 in modulating PDAC initiation and progression. We tested the cell intrinsic role of COX-2 in PDAC progression using both loss-of-function and gain-of-function approaches. Cox-2 deletion in Pdx1+ pancreatic progenitor cells significantly delays the development of PDAC in mice with K-ras activation and Pten haploinsufficiency. Conversely, COX-2 overexpression promotes early onset and progression of PDAC in the K-ras mouse model. Loss of PTEN function is a critical factor in determining lethal PDAC onset and overall survival. Mechanistically, COX-2 overexpression increases p-AKT levels in the precursor lesions of Pdx1(+); K-ras(G12D)(/+); Pten(lox)(/+) mice in the absence of Pten LOH. In contrast, Cox-2 deletion in the same setting diminishes p-AKT levels and delays cancer progression. These data suggest an important cell intrinsic role for COX-2 in tumor initiation and progression through activation of the PI3K/AKT pathway. PDAC that is independent of intrinsic COX-2 expression eventually develops with decreased FKBP5 and increased GRP78 expression, two alternate pathways leading to AKT activation. Together, these results support a cell intrinsic role for COX-2 in PDAC development and suggest that while anti-COX-2 therapy may delay the development and progression of PDAC, mechanisms known to increase chemoresistance through AKT activation must also be overcome.
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Affiliation(s)
- Reginald Hill
- Corresponding Author: Hong Wu, Department of Molecular and Medical Pharmacology, CHS 33-131, 650 CE Young Drive South, Los Angeles, CA 90095, USA
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29
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Abstract
PURPOSE OF REVIEW Despite being a subject of much scientific scrutiny, the pathogenesis of acute pancreatitis is still not well understood. This article reviews recent advances in our understanding of acute pancreatitis. RECENT FINDINGS Zymogen activation, observed within acini early during acute pancreatitis for a long time, was shown to be sufficient to induce acute pancreatitis. Another key early event, NFκB activation, has previously been shown to induce acute pancreatitis. The relationship between these two key early steps is beginning to be clarified. Mechanisms of zymogen activation - pathologic calcium signaling, pH changes, colocalization and autophagy, and of NFκB activation have been investigated intensively along with potential therapeutic targets both upstream and downstream of these key events. Additional key findings have been elucidation of the role of bioenergetics and the dual role of oxidative stress in acute pancreatitis, recognition of endoplasmic reticulum stress as an early step and the status of duct cells as important entities in pancreatic injury. SUMMARY Current findings have provided further insight into the roles and mechanisms of zymogen activation and inflammatory pathways in pancreatic injury. Future studies, which will be of great importance in identifying therapeutic targets, are being undertaken to establish the relative contributions of these pathways during acute pancreatitis.
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Ye R, Ni M, Wang M, Luo S, Zhu G, Chow RH, Lee AS. Inositol 1,4,5-trisphosphate receptor 1 mutation perturbs glucose homeostasis and enhances susceptibility to diet-induced diabetes. J Endocrinol 2011; 210:209-17. [PMID: 21565852 PMCID: PMC3137733 DOI: 10.1530/joe-11-0012] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The inositol 1,4,5-trisphosphate receptors (IP3Rs) as ligand-gated Ca(2)(+) channels are key modulators of cellular processes. Despite advances in understanding their critical role in regulating neuronal function and cell death, how this family of proteins impact cell metabolism is just emerging. Unexpectedly, a transgenic mouse line (D2D) exhibited progressive glucose intolerance as a result of transgene insertion. Inverse PCR was used to identify the gene disruption in the D2D mice. This led to the discovery that Itpr1 is among the ten loci disrupted in chromosome 6. Itpr1 encodes for IP3R1, the most abundant IP3R isoform in mouse brain and also highly expressed in pancreatic β-cells. To study IP3R1 function in glucose metabolism, we used the Itpr1 heterozygous mutant mice, opt/+. Glucose homeostasis in male mice cohorts was examined by multiple approaches of metabolic phenotyping. Under regular diet, the opt/+ mice developed glucose intolerance but no insulin resistance. Decrease in second-phase glucose-stimulated blood insulin level was observed in opt/+ mice, accompanied by reduced β-cell mass and insulin content. Strikingly, when fed with high-fat diet, the opt/+ mice were more susceptible to the development of hyperglycemia, glucose intolerance, and insulin resistance. Collectively, our studies identify the gene Itpr1 being interrupted in the D2D mice and uncover a novel role of IP3R1 in regulation of in vivo glucose homeostasis and development of diet-induced diabetes.
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Affiliation(s)
- Risheng Ye
- Department of Biochemistry and Molecular Biology, USC Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, 1441 Eastlake Avenue, Los Angeles, California 90089-9176, USA
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31
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Pandol SJ, Gorelick FS, Lugea A. Environmental and genetic stressors and the unfolded protein response in exocrine pancreatic function - a hypothesis. Front Physiol 2011; 2:8. [PMID: 21483727 PMCID: PMC3070477 DOI: 10.3389/fphys.2011.00008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 02/24/2011] [Indexed: 01/11/2023] Open
Abstract
The exocrine pancreas has the greatest protein synthetic capacity of any mammalian organ and is challenged with the synthesis, processing and transporting a large load of digestive enzymes. Based on recent findings we present a hypothesis proposing that mutations in the digestive enzymes and environmental risks impacting the pancreas (i.e., alcohol abuse, smoking, metabolic disorders, and drugs) cause endoplasmic reticulum (ER) stress. We review recent findings showing that in normal pancreas the ER stress resulting from alcohol abuse leads to an adaptive unfolded protein response (UPR) allowing for maintenance of protein synthesis, processing, and transport. However, when key pathways necessary for the adaptive UPR are altered, the exocrine cell of the pancreas is unable to maintain these processes and cellular pathology results. These findings may explain why some individuals with alcohol abuse disorders develop organ injury and disease while most do not. Further, the findings allow us to hypothesize that the UPR in the exocrine pancreas adapts the protein synthetic machinery of the ER stress resulting from mutational and environmental stressors. When the ability of the UPR to adapt to the stressors is exceeded, pathologic pathways and disease develop.
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Affiliation(s)
- Stephen J Pandol
- Department of Veterans Affairs, Southern California Research Center for Alcoholic Liver and Pancreatic Diseases, University of California Los Angeles, CA, USA
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32
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Pfaffenbach KT, Lee AS. The critical role of GRP78 in physiologic and pathologic stress. Curr Opin Cell Biol 2010; 23:150-6. [PMID: 20970977 DOI: 10.1016/j.ceb.2010.09.007] [Citation(s) in RCA: 239] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Accepted: 09/25/2010] [Indexed: 11/17/2022]
Abstract
GRP78 is a major endoplasmic reticulum chaperone as well as a master regulator of the unfolded protein response. In addition to playing an essential role in early embryonic development, recent studies have emerged specifically implicating GRP78 and chaperone integrity in the aging process and age-related diseases. Another exciting discovery is the regulation of GRP78 by insulin/IGF-1 signaling pathways impacting cell proliferation and survival. Mouse models of cancer, in combination with cell culture studies, validate the critical role of GRP78 in tumorigenesis and tumor angiogenesis. Further, these studies demonstrate the ability of GRP78 to suppress oncogenic PI3K/AKT signaling. The discovery of cell surface GRP78, in cancer cells and cells undergoing ER stress, presents a novel therapeutic strategy.
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Affiliation(s)
- Kyle T Pfaffenbach
- Department of Biochemistry and Molecular Biology, University of Southern California Keck School of Medicine, USC Norris Comprehensive Cancer Center, 1441 Eastlake Avenue, Los Angeles, CA 90089-9176, USA
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