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Białek W, Hryniewicz-Jankowska A, Czechowicz P, Sławski J, Collawn JF, Czogalla A, Bartoszewski R. The lipid side of unfolded protein response. Biochim Biophys Acta Mol Cell Biol Lipids 2024; 1869:159515. [PMID: 38844203 DOI: 10.1016/j.bbalip.2024.159515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/16/2024] [Accepted: 05/31/2024] [Indexed: 06/12/2024]
Abstract
Although our current knowledge of the molecular crosstalk between the ER stress, the unfolded protein response (UPR), and lipid homeostasis remains limited, there is increasing evidence that dysregulation of either protein or lipid homeostasis profoundly affects the other. Most research regarding UPR signaling in human diseases has focused on the causes and consequences of disrupted protein folding. The UPR itself consists of very complex pathways that function to not only maintain protein homeostasis, but just as importantly, modulate lipid biogenesis to allow the ER to adjust and promote cell survival. Lipid dysregulation is known to activate many aspects of the UPR, but the complexity of this crosstalk remains a major research barrier. ER lipid disequilibrium and lipotoxicity are known to be important contributors to numerous human pathologies, including insulin resistance, liver disease, cardiovascular diseases, neurodegenerative diseases, and cancer. Despite their medical significance and continuous research, however, the molecular mechanisms that modulate lipid synthesis during ER stress conditions, and their impact on cell fate decisions, remain poorly understood. Here we summarize the current view on crosstalk and connections between altered lipid metabolism, ER stress, and the UPR.
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Affiliation(s)
- Wojciech Białek
- Department of Biophysics, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | | | - Paulina Czechowicz
- Department of Biophysics, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Jakub Sławski
- Department of Biophysics, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - James F Collawn
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, USA
| | - Aleksander Czogalla
- Department of Cytobiochemistry, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Rafał Bartoszewski
- Department of Biophysics, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland.
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2
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Wang W, Dong L, Lv H, An Y, Zhang C, Zheng Z, Guo Y, He L, Wang L, Wang J, Shi X, Li N, Zheng M. Downregulating miRNA-199a-5p exacerbates fluorouracil-induced cardiotoxicity by activating the ATF6 signaling pathway. Aging (Albany NY) 2024; 16:5916-5928. [PMID: 38536006 PMCID: PMC11042954 DOI: 10.18632/aging.205679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 02/27/2024] [Indexed: 04/23/2024]
Abstract
BACKGROUND Fluorouracil (5-FU) might produce serious cardiac toxic reactions. miRNA-199a-5p is a miRNA primarily expressed in myocardial cells and has a protective effect on vascular endothelium. Under hypoxia stress, the expression level of miRNA-199a-5p was significantly downregulated and is closely related to cardiovascular events such as coronary heart disease, heart failure, and hypertension. We explored whether 5-FU activates the endoplasmic reticulum stress ATF6 pathway by regulating the expression of miRNA-199a-5p in cardiac toxicity. METHODS This project established a model of primary cardiomyocytes derived from neonatal rats and treated them with 5-FU in vitro. The expression of miRNA-199a-5p and its regulation were explored in vitro and in vivo. RESULTS 5-FU decreases the expression of miRNA-199a-5p in cardiomyocytes, activates the endoplasmic reticulum stress ATF6 pathway, and increases the expression of GRP78 and ATF6, affecting the function of cardiomyocytes, and induces cardiac toxicity. The rescue assay further confirmed that miRNA-199a-5p supplementation can reduce the cardiotoxicity caused by 5-FU, and its protective effect on cardiomyocytes depends on the downregulation of the endoplasmic reticulum ATF6 signaling pathway. CONCLUSIONS 5-FU can down-regulate expression of miRNA-199a-5p, then activate the endoplasmic reticulum stress ATF6 pathway, increase the expression of GRP78 and ATF6, affect the function of cardiomyocytes, and induce cardiac toxicity.
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Affiliation(s)
- Wei Wang
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Liang Dong
- Department of Cardiology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031, Hebei, China
| | - Hengxu Lv
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Yonghui An
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Changwang Zhang
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Zheng Zheng
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Ying Guo
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Li He
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Libin Wang
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Jinmei Wang
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Xinlei Shi
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Na Li
- Department of Oncology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031 Hebei, China
| | - Mingqi Zheng
- Department of Cardiology, The First Hospital of Hebei Medical University, Yuhua, Shijiazhuang 050031, Hebei, China
- Hebei Key Laboratory of Heart and Metabolism, Shijiazhuang 050031, Hebei, China
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3
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Zhang L, Zhang J, Ye ZW, Muhammad A, Li L, Culpepper JW, Townsend DM, Tew KD. Adaptive changes in tumor cells in response to reductive stress. Biochem Pharmacol 2024; 219:115929. [PMID: 38000559 PMCID: PMC10895707 DOI: 10.1016/j.bcp.2023.115929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 11/26/2023]
Abstract
Reductive stress is characterized by an excess of cellular electron donors and can be linked with various human pathologies including cancer. We developed melanoma cell lines resistant to reductive stress agents: rotenone (ROTR), n-acetyl-L-cysteine, (NACR), or dithiothreitol (DTTR). Resistant cells divided more rapidly and had intracellular homeostatic redox-couple ratios that were shifted towards the reduced state. Resistance caused alterations in general cell morphology, but only ROTR cells had significant changes in mitochondrial morphology with higher numbers that were more isolated, fragmented and swollen, with greater membrane depolarization and decreased numbers of networks. These changes were accompanied by lower basal oxygen consumption and maximal respiration rates. Whole cell flux analyses and mitochondrial function assays showed that NACR and DTTR preferentially utilized tricarboxylic acid (TCA) cycle intermediates, while ROTR used ketone body substrates such as D, L-β-hydroxybutyric acid. NACR and DTTR cells had constitutively decreased levels of reactive oxygen species (ROS), although this was accompanied by activation of nuclear factor erythroid 2-related factor 2 (Nrf2), with concomitant increased expression of the downstream gene products such as glutathione S-transferase P (GSTP). Further adaptations included enhanced expression of endoplasmic reticulum proteins controlling the unfolded protein response (UPR). Although expression patterns of these UPR proteins were distinct between the resistant cells, a trend implied that resistance to reductive stress is accompanied by a constitutively increased UPR phenotype in each line. Overall, tumor cells, although tolerant of oxidative stress, can adapt their energy and survival mechanisms in lethal reductive stress conditions.
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Affiliation(s)
- Leilei Zhang
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 70 President St., DD410, Charleston, SC 29425, USA
| | - Jie Zhang
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 70 President St., DD410, Charleston, SC 29425, USA
| | - Zhi-Wei Ye
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 70 President St., DD410, Charleston, SC 29425, USA
| | - Aslam Muhammad
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 70 President St., DD410, Charleston, SC 29425, USA
| | - Li Li
- Department of Drug Discovery and Experimental Sciences, Medical University of South Carolina, 274 Calhoun Street MSC 141, Charleston, S.C. 29425-1410, USA
| | - John W Culpepper
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 70 President St., DD410, Charleston, SC 29425, USA
| | - Danyelle M Townsend
- Department of Drug Discovery and Experimental Sciences, Medical University of South Carolina, 274 Calhoun Street MSC 141, Charleston, S.C. 29425-1410, USA
| | - Kenneth D Tew
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 70 President St., DD410, Charleston, SC 29425, USA.
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4
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Kozalak G, Koşar A. Autophagy-related mechanisms for treatment of multiple myeloma. CANCER DRUG RESISTANCE (ALHAMBRA, CALIF.) 2023; 6:838-857. [PMID: 38239705 PMCID: PMC10792488 DOI: 10.20517/cdr.2023.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/12/2023] [Accepted: 12/20/2023] [Indexed: 01/22/2024]
Abstract
Multiple myeloma (MM) is a type of hematological cancer that occurs when B cells become malignant. Various drugs such as proteasome inhibitors, immunomodulators, and compounds that cause DNA damage can be used in the treatment of MM. Autophagy, a type 2 cell death mechanism, plays a crucial role in determining the fate of B cells, either promoting their survival or inducing cell death. Therefore, autophagy can either facilitate the progression or hinder the treatment of MM disease. In this review, autophagy mechanisms that may be effective in MM cells were covered and evaluated within the contexts of unfolded protein response (UPR), bone marrow microenvironment (BMME), drug resistance, hypoxia, DNA repair and transcriptional regulation, and apoptosis. The genes that are effective in each mechanism and research efforts on this subject were discussed in detail. Signaling pathways targeted by new drugs to benefit from autophagy in MM disease were covered. The efficacy of drugs that regulate autophagy in MM was examined, and clinical trials on this subject were included. Consequently, among the autophagy mechanisms that are effective in MM, the most suitable ones to be used in the treatment were expressed. The importance of 3D models and microfluidic systems for the discovery of new drugs for autophagy and personalized treatment was emphasized. Ultimately, this review aims to provide a comprehensive overview of MM disease, encompassing autophagy mechanisms, drugs, clinical studies, and further studies.
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Affiliation(s)
- Gül Kozalak
- Faculty of Engineering and Natural Science, Sabancı University, Istanbul 34956, Turkey
- Center of Excellence for Functional Surfaces and Interfaces for Nano Diagnostics (EFSUN), Sabancı University, Istanbul 34956, Turkey
| | - Ali Koşar
- Faculty of Engineering and Natural Science, Sabancı University, Istanbul 34956, Turkey
- Center of Excellence for Functional Surfaces and Interfaces for Nano Diagnostics (EFSUN), Sabancı University, Istanbul 34956, Turkey
- Turkish Academy of Sciences (TÜBA), Çankaya, Ankara 06700, Turkey
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5
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Kunes RZ, Walle T, Land M, Nawy T, Pe'er D. Supervised discovery of interpretable gene programs from single-cell data. Nat Biotechnol 2023:10.1038/s41587-023-01940-3. [PMID: 37735262 PMCID: PMC10958532 DOI: 10.1038/s41587-023-01940-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 08/09/2023] [Indexed: 09/23/2023]
Abstract
Factor analysis decomposes single-cell gene expression data into a minimal set of gene programs that correspond to processes executed by cells in a sample. However, matrix factorization methods are prone to technical artifacts and poor factor interpretability. We address these concerns with Spectra, an algorithm that combines user-provided gene programs with the detection of novel programs that together best explain expression covariation. Spectra incorporates existing gene sets and cell-type labels as prior biological information, explicitly models cell type and represents input gene sets as a gene-gene knowledge graph using a penalty function to guide factorization toward the input graph. We show that Spectra outperforms existing approaches in challenging tumor immune contexts, as it finds factors that change under immune checkpoint therapy, disentangles the highly correlated features of CD8+ T cell tumor reactivity and exhaustion, finds a program that explains continuous macrophage state changes under therapy and identifies cell-type-specific immune metabolic programs.
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Affiliation(s)
- Russell Z Kunes
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Department of Statistics, Columbia University, New York, NY, USA
| | - Thomas Walle
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Clinical Cooperation Unit Virotherapy, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department of Medical Oncology, National Center for Tumor Diseases, Heidelberg University Hospital, Heidelberg, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Max Land
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Tal Nawy
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Dana Pe'er
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
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Bartoszewska S, Sławski J, Collawn JF, Bartoszewski R. Dual RNase activity of IRE1 as a target for anticancer therapies. J Cell Commun Signal 2023:10.1007/s12079-023-00784-5. [PMID: 37721642 DOI: 10.1007/s12079-023-00784-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 08/31/2023] [Indexed: 09/19/2023] Open
Abstract
The unfolded protein response (UPR) is a cellular mechanism that protects cells during stress conditions in which there is an accumulation of misfolded proteins in the endoplasmic reticulum (ER). UPR activates three signaling pathways that function to alleviate stress conditions and promote cellular homeostasis and cell survival. During unmitigated stress conditions, however, UPR activation signaling changes to promote cell death through apoptosis. Interestingly, cancer cells take advantage of this pathway to facilitate survival and avoid apoptosis even during prolonged cell stress conditions. Here, we discuss different signaling pathways associated with UPR and focus specifically on one of the ER signaling pathways activated during UPR, inositol-requiring enzyme 1α (IRE1). The rationale is that the IRE1 pathway is associated with cell fate decisions and recognized as a promising target for cancer therapeutics. Here we discuss IRE1 inhibitors and how they might prove to be an effective cancer therapeutic.
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Affiliation(s)
- Sylwia Bartoszewska
- Department of Inorganic Chemistry, Medical University of Gdansk, Gdansk, Poland
| | - Jakub Sławski
- Department of Biophysics, Faculty of Biotechnology, University of Wrocław, F. Joliot-Curie 14a Street, 50-383, Wrocław, Poland
| | - James F Collawn
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, 35233, USA
| | - Rafał Bartoszewski
- Department of Biophysics, Faculty of Biotechnology, University of Wrocław, F. Joliot-Curie 14a Street, 50-383, Wrocław, Poland.
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7
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Huang W, Gong Y, Yan L. ER Stress, the Unfolded Protein Response and Osteoclastogenesis: A Review. Biomolecules 2023; 13:1050. [PMID: 37509086 PMCID: PMC10377020 DOI: 10.3390/biom13071050] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 06/24/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023] Open
Abstract
Endoplasmic reticulum (ER) stress and its adaptive mechanism, the unfolded protein response (UPR), are triggered by the accumulation of unfolded and misfolded proteins. During osteoclastogenesis, a large number of active proteins are synthesized. When an imbalance in the protein folding process occurs, it causes osteoclasts to trigger the UPR. This close association has led to the role of the UPR in osteoclastogenesis being increasingly explored. In recent years, several studies have reported the role of ER stress and UPR in osteoclastogenesis and bone resorption. Here, we reviewed the relevant literature and discussed the UPR signaling cascade response, osteoclastogenesis-related signaling pathways, and the role of UPR in osteoclastogenesis and bone resorption in detail. It was found that the UPR signal (PERK, CHOP, and IRE1-XBP1) promoted the expression of the receptor activator of the nuclear factor-kappa B ligand (RANKL) in osteoblasts and indirectly enhanced osteoclastogenesis. IRE1 promoted osteoclastogenesis via promoting NF-κB, MAPK signaling, or the release of pro-inflammatory factors (IL-6, IL-1β, and TNFα). CREBH promoted osteoclast differentiation by promoting NFATc1 expression. The PERK signaling pathway also promoted osteoclastogenesis through NF-κB and MAPK signaling pathways, autophagy, and RANKL secretion from osteoblasts. However, salubrinal (an inhibitor of eIF2α dephosphorylation that upregulated p-eIF2α expression) directly inhibited osteoclastogenesis by suppressing NFATc1 expression and indirectly promoted osteoclastogenesis by promoting RANKL secretion from osteoblasts. Therefore, the specific effects and mechanisms of p-PERK and its downstream signaling on osteoclastogenesis still need further experiments to confirm. In addition, the exact role of ATF6 and BiP in osteoclastogenesis also required further exploration. In conclusion, our detailed and systematic review provides some references for the next step to fully elucidate the relationship between UPR and osteoclastogenesis, intending to provide new insights for the treatment of diseases caused by osteoclast over-differentiation, such as osteoporosis.
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Affiliation(s)
- Wangli Huang
- Department of Spine Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, China
| | - Yining Gong
- Department of Spine Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, China
| | - Liang Yan
- Department of Spine Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, China
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8
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Yeap JW, Ali IAH, Ibrahim B, Tan ML. Chronic obstructive pulmonary disease and emerging ER stress-related therapeutic targets. Pulm Pharmacol Ther 2023; 81:102218. [PMID: 37201652 DOI: 10.1016/j.pupt.2023.102218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 05/05/2023] [Indexed: 05/20/2023]
Abstract
COPD pathogenesis is frequently associated with endoplasmic reticulum stress (ER stress) progression. Targeting the major unfolded protein response (UPR) branches in the ER stress pathway may provide pharmacotherapeutic selection strategies for treating COPD and enable relief from its symptoms. In this study, we aimed to systematically review the potential role of the ER stress inhibitors of major UPR branches (IRE1, PERK, and ATF6) in COPD-related studies and determine the current stage of knowledge in this field. The systematic review was carried out adhering to the PRISMA checklist based on published studies obtained from specific keyword searches of three databases, namely PubMed, ScienceDirect and Springer Database. The search was limited to the year 2000-2022 which includes all in vitro studies, in vivo studies and clinical trials related to the application of ER stress inhibitors toward COPD-induced models and disease. The risk of bias was evaluated using the QUIN, SYRCLE, revised Cochrane risk of bias tool for randomized trials (RoB 2.0) and NIH tool respectively. A total of 7828 articles were screened from three databases and a final total of 37 studies were included in the review. The ER stress and UPR pathways are potentially useful to prevent COPD progression and attenuate the exacerbation of COPD and related symptoms. Interestingly, the off-target effects from inhibition of the UPR pathway may be desirable or undesirable depending on context and therapeutic applications. Targeting the UPR pathway could have complex consequences as the production of ER molecules involved in folding may be impaired which could continuously provoke misfolding of proteins. Although several emerging compounds were noted to be potentially useful for targeted therapy against COPD, clinical studies have yet to be thoroughly explored.
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Affiliation(s)
- Jia Wen Yeap
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800, Pulau, Pinang, Malaysia
| | - Irfhan Ali Hyder Ali
- Respiratory Department, Penang General Hospital, Jalan Residensi, 10990, Pulau, Pinang, Malaysia
| | - Baharudin Ibrahim
- Department of Clinical Pharmacy & Pharmacy Practice, Faculty of Pharmacy, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Mei Lan Tan
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800, Pulau, Pinang, Malaysia; Centre For Global Sustainability Studies (CGSS), Universiti Sains Malaysia, 11800, Pulau, Pinang, Malaysia.
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9
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Groenendyk J, Michalak M. Interplay between calcium and endoplasmic reticulum stress. Cell Calcium 2023; 113:102753. [PMID: 37209448 DOI: 10.1016/j.ceca.2023.102753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/22/2023]
Abstract
Cellular homeostasis is crucial for the healthy functioning of the organism. Disruption of cellular homeostasis activates endoplasmic reticulum (ER) stress coping responses including the unfolded protein response (UPR). There are three ER resident stress sensors responsible for UPR activation - IRE1α, PERK and ATF6. Ca2+ signaling plays an important role in stress responses including the UPR and the ER is the main Ca2+ storage organelle and a source of Ca2+ for cell signaling. The ER contains many proteins involved in Ca2+ import/export/ storage, Ca2+ movement between different cellular organelles and ER Ca2+ stores refilling. Here we focus on selected aspects of ER Ca2+ homeostasis and its role in activation of the ER stress coping responses.
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Affiliation(s)
- Jody Groenendyk
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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10
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Koppes EA, Johnson MA, Moresco JJ, Luppi P, Lewis DW, Stolz DB, Diedrich JK, Yates JR, Wek RC, Watkins SC, Gollin SM, Park HJ, Drain P, Nicholls RD. Insulin secretion deficits in a Prader-Willi syndrome β-cell model are associated with a concerted downregulation of multiple endoplasmic reticulum chaperones. PLoS Genet 2023; 19:e1010710. [PMID: 37068109 PMCID: PMC10138222 DOI: 10.1371/journal.pgen.1010710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 04/27/2023] [Accepted: 03/21/2023] [Indexed: 04/18/2023] Open
Abstract
Prader-Willi syndrome (PWS) is a multisystem disorder with neurobehavioral, metabolic, and hormonal phenotypes, caused by loss of expression of a paternally-expressed imprinted gene cluster. Prior evidence from a PWS mouse model identified abnormal pancreatic islet development with retention of aged insulin and deficient insulin secretion. To determine the collective roles of PWS genes in β-cell biology, we used genome-editing to generate isogenic, clonal INS-1 insulinoma lines having 3.16 Mb deletions of the silent, maternal- (control) and active, paternal-allele (PWS). PWS β-cells demonstrated a significant cell autonomous reduction in basal and glucose-stimulated insulin secretion. Further, proteomic analyses revealed reduced levels of cellular and secreted hormones, including all insulin peptides and amylin, concomitant with reduction of at least ten endoplasmic reticulum (ER) chaperones, including GRP78 and GRP94. Critically, differentially expressed genes identified by whole transcriptome studies included reductions in levels of mRNAs encoding these secreted peptides and the group of ER chaperones. In contrast to the dosage compensation previously seen for ER chaperones in Grp78 or Grp94 gene knockouts or knockdown, compensation is precluded by the stress-independent deficiency of ER chaperones in PWS β-cells. Consistent with reduced ER chaperones levels, PWS INS-1 β-cells are more sensitive to ER stress, leading to earlier activation of all three arms of the unfolded protein response. Combined, the findings suggest that a chronic shortage of ER chaperones in PWS β-cells leads to a deficiency of protein folding and/or delay in ER transit of insulin and other cargo. In summary, our results illuminate the pathophysiological basis of pancreatic β-cell hormone deficits in PWS, with evolutionary implications for the multigenic PWS-domain, and indicate that PWS-imprinted genes coordinate concerted regulation of ER chaperone biosynthesis and β-cell secretory pathway function.
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Affiliation(s)
- Erik A Koppes
- Division of Genetic and Genomic Medicine, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Marie A Johnson
- Division of Genetic and Genomic Medicine, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - James J Moresco
- Department of Molecular Medicine and Neurobiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Patrizia Luppi
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Dale W Lewis
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, United States of America
| | - Donna B Stolz
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Jolene K Diedrich
- Department of Molecular Medicine and Neurobiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - John R Yates
- Department of Molecular Medicine and Neurobiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Ronald C Wek
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Simon C Watkins
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Susanne M Gollin
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, United States of America
| | - Hyun Jung Park
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, United States of America
| | - Peter Drain
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Robert D Nicholls
- Division of Genetic and Genomic Medicine, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
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11
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Brownrigg GP, Xia YH, Chu CMJ, Wang S, Chao C, Zhang JA, Skovsø S, Panzhinskiy E, Hu X, Johnson JD, Rideout EJ. Sex differences in islet stress responses support female β cell resilience. Mol Metab 2023; 69:101678. [PMID: 36690328 PMCID: PMC9971554 DOI: 10.1016/j.molmet.2023.101678] [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: 10/12/2022] [Revised: 01/07/2023] [Accepted: 01/17/2023] [Indexed: 01/21/2023] Open
Abstract
OBJECTIVE Pancreatic β cells play a key role in maintaining glucose homeostasis; dysfunction of this critical cell type causes type 2 diabetes (T2D). Emerging evidence points to sex differences in β cells, but few studies have examined male-female differences in β cell stress responses and resilience across multiple contexts, including diabetes. Here, we address the need for high-quality information on sex differences in β cell and islet gene expression and function using both human and rodent samples. METHODS In humans, we compared β cell gene expression and insulin secretion in donors with T2D to non-diabetic donors in both males and females. In mice, we generated a well-powered islet RNAseq dataset from 20-week-old male and female siblings with similar insulin sensitivity. Our unbiased gene expression analysis pointed to a sex difference in the endoplasmic reticulum (ER) stress response. Based on this analysis, we hypothesized female islets would be more resilient to ER stress than male islets. To test this, we subjected islets isolated from age-matched male and female mice to thapsigargin treatment and monitored protein synthesis, cell death, and β cell insulin production and secretion. Transcriptomic and proteomic analyses were used to characterize sex differences in islet responses to ER stress. RESULTS Our single-cell analysis of human β cells revealed sex-specific changes to gene expression and function in T2D, correlating with more robust insulin secretion in human islets isolated from female donors with T2D compared to male donors with T2D. In mice, RNA sequencing revealed differential enrichment of unfolded protein response pathway-associated genes, where female islets showed higher expression of genes linked with protein synthesis, folding, and processing. This differential expression was physiologically significant, as islets isolated from female mice were more resilient to ER stress induction with thapsigargin. Specifically, female islets showed a greater ability to maintain glucose-stimulated insulin production and secretion during ER stress compared with males. CONCLUSIONS Our data demonstrate sex differences in β cell gene expression in both humans and mice, and that female β cells show a greater ability to maintain glucose-stimulated insulin secretion across multiple physiological and pathological contexts.
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Affiliation(s)
- George P Brownrigg
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Yi Han Xia
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Chieh Min Jamie Chu
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Su Wang
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Charlotte Chao
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Jiashuo Aaron Zhang
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Søs Skovsø
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Evgeniy Panzhinskiy
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Xiaoke Hu
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - James D Johnson
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada.
| | - Elizabeth J Rideout
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada.
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12
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Chen CY, Leu HB, Wang SC, Tsai SH, Chou RH, Lu YW, Tsai YL, Kuo CS, Huang PH, Chen JW, Lin SJ. Inhibition of Trimethylamine N-Oxide Attenuates Neointimal Formation Through Reduction of Inflammasome and Oxidative Stress in a Mouse Model of Carotid Artery Ligation. Antioxid Redox Signal 2023; 38:215-233. [PMID: 35713239 DOI: 10.1089/ars.2021.0115] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Aims: Trimethylamine-N-oxide (TMAO) is a metabolite generated from dietary choline, betaine, and l-carnitine, after their oxidization in the liver. TMAO has been identified as a novel independent risk factor for atherosclerosis through the induction of vascular inflammation. However, the effect of TMAO on neointimal formation in response to vascular injury remains unclear. Results: This study was conducted using a murine model of acutely disturbed flow-induced atherosclerosis induced by partial carotid artery ligation. 3,3-Dimethyl-1-butanol (DMB) was used to reduce TMAO concentrations. Wild-type mice were divided into four groups [regular diet, high-TMAO diet, high-choline diet, and high-choline diet+DMB] to investigate the effects of TMAO elevation and its inhibition by DMB. Mice fed high-TMAO and high-choline diets had significantly enhanced neointimal hyperplasia and advanced plaques, elevated arterial elastin fragmentation, increased macrophage infiltration and inflammatory cytokine secretion, and enhanced activation of nuclear factor (NF)-κB, the NLRP3 inflammasome, and endoplasmic reticulum (ER) stress relative to the control group. Mice fed high-choline diets with DMB treatment exhibited attenuated flow-induced atherosclerosis, inflammasome expression, ER stress, and reactive oxygen species expression. Human aortic smooth muscle cells (HASMCs) were used to investigate the mechanism of TMAO-induced injury. The HASMCs were treated with TMAO with or without an ER stress inhibitor to determine whether inhibition of ER stress modulates the TMAO-induced inflammatory response. Innovation: This study demonstrates that TMAO regulates vascular remodeling via ER stress. Conclusion: Our findings demonstrate that TMAO elevation promotes disturbed flow-induced atherosclerosis and that DMB administration mitigates vascular remodeling, suggesting a rationale for a TMAO-targeted strategy for the treatment of atherosclerosis. Antioxid. Redox Signal. 38, 215-233.
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Affiliation(s)
- Chi-Yu Chen
- Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Hsin-Bang Leu
- Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.,Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Shen-Chih Wang
- Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan.,Healthcare and Services Center, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Shih-Hung Tsai
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ruey-Hsing Chou
- Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.,Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Institute of Pharmacology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ya-Wen Lu
- Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Yi-Lin Tsai
- Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chin-Sung Kuo
- Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Cardiovascular Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Po-Hsun Huang
- Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.,Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Institute of Pharmacology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Jaw-Wen Chen
- Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Shing-Jong Lin
- Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.,Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Taipei Heart Institute, Taipei Medical University, Taipei, Taiwan.,Division of Cardiology, Heart Center, Cheng-Hsin General Hospital, Taipei, Taiwan
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13
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Endoplasmic Reticulum Stress in Hepatitis B Virus and Hepatitis C Virus Infection. Viruses 2022; 14:v14122630. [PMID: 36560634 PMCID: PMC9780809 DOI: 10.3390/v14122630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/20/2022] [Accepted: 11/23/2022] [Indexed: 11/29/2022] Open
Abstract
Endoplasmic reticulum (ER) stress, a type of cellular stress, always occurs when unfolded or misfolded proteins accumulating in the ER exceed the protein folding capacity. Because of the demand for rapid viral protein synthesis after viral infection, viral infections become a risk factor for ER stress. The hepatocyte is a cell with large and well-developed ER, and hepatitis virus infection is widespread in the population, indicating the interaction between hepatitis viruses and ER stress may have significance for managing liver diseases. In this paper, we review the process that is initiated by the hepatocyte through ER stress against HBV and HCV infection and explain how this information can be helpful in the treatment of HBV/HCV-related diseases.
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14
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Shrestha S, Erikson G, Lyon J, Spigelman AF, Bautista A, Manning Fox JE, dos Santos C, Shokhirev M, Cartailler JP, Hetzer MW, MacDonald PE, Arrojo e Drigo R. Aging compromises human islet beta cell function and identity by decreasing transcription factor activity and inducing ER stress. SCIENCE ADVANCES 2022; 8:eabo3932. [PMID: 36197983 PMCID: PMC9534504 DOI: 10.1126/sciadv.abo3932] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 08/17/2022] [Indexed: 05/02/2023]
Abstract
Pancreatic islet beta cells are essential for maintaining glucose homeostasis. To understand the impact of aging on beta cells, we performed meta-analysis of single-cell RNA sequencing datasets, transcription factor (TF) regulon analysis, high-resolution confocal microscopy, and measured insulin secretion from nondiabetic donors spanning most of the human life span. This revealed the range of molecular and functional changes that occur during beta cell aging, including the transcriptional deregulation that associates with cellular immaturity and reorganization of beta cell TF networks, increased gene transcription rates, and reduced glucose-stimulated insulin release. These alterations associate with activation of endoplasmic reticulum (ER) stress and autophagy pathways. We propose that a chronic state of ER stress undermines old beta cell structure function to increase the risk of beta cell failure and type 2 diabetes onset as humans age.
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Affiliation(s)
- Shristi Shrestha
- Creative Data Solutions, Vanderbilt Center for Stem Cell Biology, Nashville, TN 37232, USA
| | - Galina Erikson
- Integrative Genomics and Bioinformatics Core, Salk Institute of Biological Studies, La Jolla, CA 92037, USA
| | - James Lyon
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G2E1, Canada
| | - Aliya F. Spigelman
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G2E1, Canada
| | - Austin Bautista
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G2E1, Canada
| | - Jocelyn E. Manning Fox
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G2E1, Canada
| | - Cristiane dos Santos
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Maxim Shokhirev
- Integrative Genomics and Bioinformatics Core, Salk Institute of Biological Studies, La Jolla, CA 92037, USA
| | | | - Martin W. Hetzer
- Molecular and Cell Biology Laboratory, Salk Institute of Biological Studies, La Jolla, CA 92037, USA
| | - Patrick E. MacDonald
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G2E1, Canada
| | - Rafael Arrojo e Drigo
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
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15
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Toll-like receptor 4-mediated endoplasmic reticulum stress induces intestinal paneth cell damage in mice following CLP-induced sepsis. Sci Rep 2022; 12:15256. [PMID: 36088483 PMCID: PMC9464222 DOI: 10.1038/s41598-022-19614-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 08/31/2022] [Indexed: 11/14/2022] Open
Abstract
A marked elevation of TLR4 was observed in various organs of septic mice. The mechanism of TLR4 in intestinal epithelial cell damage in sepsis remains unclear. CLP mice models were used to assess the role of TLR4 in intestinal Paneth cell damage by histological, polymerase chain reaction, western-blot analyses. The ileal expression of TLR4 was increased by more than five-fold after CLP. CLP significantly increased 7-day mortality and was associated with a higher murine sepsis score (MSS), closely related with increased TLR4 expression. Histological staining revealed that a reduced number of Paneth cells, accompanied by reduced lysozyme and defensin alpha 5(DEF-5) expression as detected by PCR. Of note, the expression levels of ATF6, XBP1 and CHOP increased in the ileal of the sepsis group. Meanwhile, the uncleaved p90 ATF6 was markedly reduced and cleaved p50 ATF6 was increased in the sepsis group. Intriguingly, The TAK-242 had improved intestinal mucosal injury, reduced the expression of ATF6, XBP1 and CHOP and relieved the cleavage of ATF6. We found that increased the expression level of TLR4 in the ileal of CLP mice promoted the depletion of Paneth cell and reduced LYZ and DEF-5 expression. Furthermore, our findings suggested that TLR4-mediated the hyperactivation of ER stress, via activating the ATF6/CHOP pathway, might be one of the mechanisms associated with Paneth cells loss and dysfunction during intestinal barrier impairment of sepsis.
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16
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Alzahrani MR, Guan BJ, Zagore LL, Wu J, Chen CW, Licatalosi DD, Baker KE, Hatzoglou M. Newly synthesized mRNA escapes translational repression during the acute phase of the mammalian unfolded protein response. PLoS One 2022; 17:e0271695. [PMID: 35947624 PMCID: PMC9365188 DOI: 10.1371/journal.pone.0271695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/06/2022] [Indexed: 11/19/2022] Open
Abstract
Endoplasmic Reticulum (ER) stress, caused by the accumulation of misfolded proteins in the ER, elicits a homeostatic mechanism known as the Unfolded Protein Response (UPR). The UPR reprograms gene expression to promote adaptation to chronic ER stress. The UPR comprises an acute phase involving inhibition of bulk protein synthesis and a chronic phase of transcriptional induction coupled with the partial recovery of protein synthesis. However, the role of transcriptional regulation in the acute phase of the UPR is not well understood. Here we analyzed the fate of newly synthesized mRNA encoding the protective and homeostatic transcription factor X-box binding protein 1 (XBP1) during this acute phase. We have previously shown that global translational repression induced by the acute UPR was characterized by decreased translation and increased stability of XBP1 mRNA. We demonstrate here that this stabilization is independent of new transcription. In contrast, we show XBP1 mRNA newly synthesized during the acute phase accumulates with long poly(A) tails and escapes translational repression. Inhibition of newly synthesized RNA polyadenylation during the acute phase decreased cell survival with no effect in unstressed cells. Furthermore, during the chronic phase of the UPR, levels of XBP1 mRNA with long poly(A) tails decreased in a manner consistent with co-translational deadenylation. Finally, additional pro-survival, transcriptionally-induced mRNAs show similar regulation, supporting the broad significance of the pre-steady state UPR in translational control during ER stress. We conclude that the biphasic regulation of poly(A) tail length during the UPR represents a previously unrecognized pro-survival mechanism of mammalian gene regulation.
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Affiliation(s)
- Mohammed R. Alzahrani
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Bo-Jhih Guan
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Leah L. Zagore
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio, United States of America
- Center for RNA Science and Therapeutics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Jing Wu
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Chien-Wen Chen
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Donny D. Licatalosi
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio, United States of America
- Center for RNA Science and Therapeutics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Kristian E. Baker
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Maria Hatzoglou
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
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17
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Lee K, Chan JY, Liang C, Ip CK, Shi YC, Herzog H, Hughes WE, Bensellam M, Delghingaro-Augusto V, Koina ME, Nolan CJ, Laybutt DR. XBP1 maintains beta cell identity, represses beta-to-alpha cell transdifferentiation and protects against diabetic beta cell failure during metabolic stress in mice. Diabetologia 2022; 65:984-996. [PMID: 35316840 PMCID: PMC9076738 DOI: 10.1007/s00125-022-05669-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 12/13/2021] [Indexed: 01/01/2023]
Abstract
AIMS/HYPOTHESIS Pancreatic beta cell dedifferentiation, transdifferentiation into other islet cells and apoptosis have been implicated in beta cell failure in type 2 diabetes, although the mechanisms are poorly defined. The endoplasmic reticulum stress response factor X-box binding protein 1 (XBP1) is a major regulator of the unfolded protein response. XBP1 expression is reduced in islets of people with type 2 diabetes, but its role in adult differentiated beta cells is unclear. Here, we assessed the effects of Xbp1 deletion in adult beta cells and tested whether XBP1-mediated unfolded protein response makes a necessary contribution to beta cell compensation in insulin resistance states. METHODS Mice with inducible beta cell-specific Xbp1 deletion were studied under normal (chow diet) or metabolic stress (high-fat diet or obesity) conditions. Glucose tolerance, insulin secretion, islet gene expression, alpha cell mass, beta cell mass and apoptosis were assessed. Lineage tracing was used to determine beta cell fate. RESULTS Deletion of Xbp1 in adult mouse beta cells led to beta cell dedifferentiation, beta-to-alpha cell transdifferentiation and increased alpha cell mass. Cell lineage-specific analyses revealed that Xbp1 deletion deactivated beta cell identity genes (insulin, Pdx1, Nkx6.1, Beta2, Foxo1) and derepressed beta cell dedifferentiation (Aldh1a3) and alpha cell (glucagon, Arx, Irx2) genes. Xbp1 deletion in beta cells of obese ob/ob or high-fat diet-fed mice triggered diabetes and worsened glucose intolerance by disrupting insulin secretory capacity. Furthermore, Xbp1 deletion increased beta cell apoptosis under metabolic stress conditions by attenuating the antioxidant response. CONCLUSIONS/INTERPRETATION These findings indicate that XBP1 maintains beta cell identity, represses beta-to-alpha cell transdifferentiation and is required for beta cell compensation and prevention of diabetes in insulin resistance states.
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Affiliation(s)
- Kailun Lee
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Jeng Yie Chan
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Cassandra Liang
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Chi Kin Ip
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Yan-Chuan Shi
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Herbert Herzog
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia
| | - William E Hughes
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Mohammed Bensellam
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia
- Secteur des sciences de la santé, Institut de recherche expérimentale et clinique, Pôle d'endocrinologie, diabète et nutrition, Université catholique de Louvain, Brussels, Belgium
| | - Viviane Delghingaro-Augusto
- Medical School and John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Mark E Koina
- ACT Pathology, Canberra Health Services, Garran, ACT, Australia
| | - Christopher J Nolan
- Medical School and John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
- Department of Endocrinology, The Canberra Hospital, Garran, ACT, Australia
| | - D Ross Laybutt
- Garvan Institute of Medical Research, St Vincent's Clinical School, UNSW Sydney, Darlinghurst, NSW, Australia.
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18
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Prasad M K, Mohandas S, Ramkumar KM. Role of ER stress inhibitors in the management of diabetes. Eur J Pharmacol 2022; 922:174893. [DOI: 10.1016/j.ejphar.2022.174893] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 12/14/2022]
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19
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Kalwat MA, Scheuner D, Rodrigues-dos-Santos K, Eizirik DL, Cobb MH. The Pancreatic ß-cell Response to Secretory Demands and Adaption to Stress. Endocrinology 2021; 162:bqab173. [PMID: 34407177 PMCID: PMC8459449 DOI: 10.1210/endocr/bqab173] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Indexed: 02/06/2023]
Abstract
Pancreatic β cells dedicate much of their protein translation capacity to producing insulin to maintain glucose homeostasis. In response to increased secretory demand, β cells can compensate by increasing insulin production capability even in the face of protracted peripheral insulin resistance. The ability to amplify insulin secretion in response to hyperglycemia is a critical facet of β-cell function, and the exact mechanisms by which this occurs have been studied for decades. To adapt to the constant and fast-changing demands for insulin production, β cells use the unfolded protein response of the endoplasmic reticulum. Failure of these compensatory mechanisms contributes to both type 1 and 2 diabetes. Additionally, studies in which β cells are "rested" by reducing endogenous insulin demand have shown promise as a therapeutic strategy that could be applied more broadly. Here, we review recent findings in β cells pertaining to the metabolic amplifying pathway, the unfolded protein response, and potential advances in therapeutics based on β-cell rest.
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Affiliation(s)
- Michael A Kalwat
- Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA
| | - Donalyn Scheuner
- Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA
| | | | - Decio L Eizirik
- Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA
- ULB Center for Diabetes Research, Medical Faculty, Université Libre de Bruxelles, Brussels, Belgium
| | - Melanie H Cobb
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
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20
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Sharma RB, Landa-Galván HV, Alonso LC. Living Dangerously: Protective and Harmful ER Stress Responses in Pancreatic β-Cells. Diabetes 2021; 70:2431-2443. [PMID: 34711668 PMCID: PMC8564401 DOI: 10.2337/dbi20-0033] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 08/03/2021] [Indexed: 01/06/2023]
Abstract
Type 2 diabetes (T2D) is a growing cause of poor health, psychosocial burden, and economic costs worldwide. The pancreatic β-cell is a cornerstone of metabolic physiology. Insulin deficiency leads to hyperglycemia, which was fatal before the availability of therapeutic insulins; even partial deficiency of insulin leads to diabetes in the context of insulin resistance. Comprising only an estimated 1 g or <1/500th of a percent of the human body mass, pancreatic β-cells of the islets of Langerhans are a vulnerable link in metabolism. Proinsulin production constitutes a major load on β-cell endoplasmic reticulum (ER), and decompensated ER stress is a cause of β-cell failure and loss in both type 1 diabetes (T1D) and T2D. The unfolded protein response (UPR), the principal ER stress response system, is critical for maintenance of β-cell health. Successful UPR guides expansion of ER protein folding capacity and increased β-cell number through survival pathways and cell replication. However, in some cases the ER stress response can cause collateral β-cell damage and may even contribute to diabetes pathogenesis. Here we review the known beneficial and harmful effects of UPR pathways in pancreatic β-cells. Improved understanding of this stress response tipping point may lead to approaches to maintain β-cell health and function.
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Affiliation(s)
- Rohit B Sharma
- Division of Endocrinology, Diabetes and Metabolism and Weill Center for Metabolic Health, Weill Cornell Medicine, New York, NY
| | - Huguet V Landa-Galván
- Division of Endocrinology, Diabetes and Metabolism and Weill Center for Metabolic Health, Weill Cornell Medicine, New York, NY
| | - Laura C Alonso
- Division of Endocrinology, Diabetes and Metabolism and Weill Center for Metabolic Health, Weill Cornell Medicine, New York, NY
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21
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Chen D, Zhu S. Whole-exome sequencing identification of a recurrent CRYBB2 variant in a four-generation Chinese family with congenital nuclear cataracts. Exp Ther Med 2021; 22:1375. [PMID: 34650623 PMCID: PMC8506933 DOI: 10.3892/etm.2021.10810] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 08/19/2021] [Indexed: 12/25/2022] Open
Abstract
Congenital cataracts is the most common cause of visual impairment and blindness in children. Although there have been extensive studies into the pathogenesis of congenital cataracts, the pathogenic mechanism underlying the recurrent variant CRYBB2:c.62T>A(p.I21N) has not been previously reported. Thus, the present study aimed to use whole-exome sequencing (WES) to identify potential genetic variants and investigate how they may have induced the occurrence of cataracts in a four-generation Chinese family with congenital nuclear cataracts. The medical history of this family was recorded and WES was conducted for one proband. Sanger sequencing was used to verify the presence of the putative variant in all participants. PolyPhen-2, SIFT and ProtScale were used to analyze the effect of the identified variants on protein function and hydrophobicity, and Pymol was used to show the structure of the wild-type (Wt) and mutant β-crystallin B2 (CRYBB2) protein. Full-length Wt-CRYBB2 or mutant-CRYBB2 (I21N-CRYBB2) were fused to green fluorescent protein (GFP), and the recombinant plasmids were transfected into HeLa cells. Reverse transcription-quantitative PCR and western blotting were used to detect the expression levels of CRYBB2 mRNA and protein. Immunofluorescence and flow cytometry analyses were used to detect protein localization and apoptosis, respectively. A recurrent variant CRYBB2:c.62T>A(p.I21N) was identified in a four-generation Chinese family with congenital nuclear cataracts. Multiple-sequence alignment of CRYBB2 demonstrated that codon 21 was highly conserved. Pymol revealed that the structure of the I21N-CRYBB2 protein was distinct from that of Wt-CRYBB2. PolyPhen-2 predicted that it had a variant provean score 1.0, suggesting it was 'probably damaging', and SIFT predicted it had a variant provean score of -5.113, indicating it was 'deleterious'. ProtScale indicated that the hydrophobicity of the mutation site was significantly reduced. The protein expression levels of the I21N-CRYBB2 were decreased compared with the Wt-CRYBB2. Immunofluorescence analysis revealed that the variant I21N-CRYBB2 protein tended to accumulate around the nucleus, and flow cytometry analysis indicated that it increased cell apoptosis. Furthermore, I21N-CRYBB2 induced the activation of the unfolded protein response (UPR). In conclusion, a pathogenic variant of CRYBB2:c.62T>A(p.I21N) was identified via WES in a four-generation Chinese family with congenital nuclear cataracts. Through biological analysis, it was found that the variant induced abnormal protein aggregation, activated the UPR and triggered excessive cell apoptosis, which may lead to the occurrence of congenital nuclear cataracts in this family.
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Affiliation(s)
- Doudou Chen
- Eye School of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610075, P.R. China.,Department of Ophthalmology, Ineye Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610032, P.R. China.,Key Laboratory of Sichuan Province Ophthalmopathy Prevention & Cure and Visual Function Protection, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610032, P.R. China
| | - Siquan Zhu
- Eye School of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610075, P.R. China.,Department of Ophthalmology, Ineye Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610032, P.R. China.,Key Laboratory of Sichuan Province Ophthalmopathy Prevention & Cure and Visual Function Protection, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610032, P.R. China.,Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100006, P.R. China
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22
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HSPB1 Is Essential for Inducing Resistance to Proteotoxic Stress in Beta-Cells. Cells 2021; 10:cells10092178. [PMID: 34571827 PMCID: PMC8472426 DOI: 10.3390/cells10092178] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/12/2021] [Accepted: 08/17/2021] [Indexed: 01/10/2023] Open
Abstract
During type 1 diabetes mellitus (T1DM) development, beta-cells undergo intense endoplasmic reticulum (ER) stress that could result in apoptosis through the failure of adaptation to the unfolded protein response (UPR). Islet transplantation is considered an attractive alternative among beta-cell replacement therapies for T1DM. To avoid the loss of beta-cells that will jeopardize the transplant’s outcome, several strategies are being studied. We have previously shown that prolactin induces protection against proinflammatory cytokines and redox imbalance-induced beta-cell death by increasing heat-shock protein B1 (HSPB1) levels. Since the role of HSPB1 in beta cells has not been deeply studied, we investigated the mechanisms involved in unbalanced protein homeostasis caused by intense ER stress and overload of the proteasomal protein degradation pathway. We tested whether HSPB1-mediated cytoprotective effects involved UPR modulation and improvement of protein degradation via the ubiquitin-proteasome system. We demonstrated that increased levels of HSPB1 attenuated levels of pro-apoptotic proteins such as CHOP and BIM, as well as increased protein ubiquitination and the speed of proteasomal protein degradation. Our data showed that HSPB1 induced resistance to proteotoxic stress and, thus, enhanced cell survival via an increase in beta-cell proteolytic capacity. These results could contribute to generate strategies aimed at the optimization of beta-cell replacement therapies.
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23
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Ricci D, Gidalevitz T, Argon Y. The special unfolded protein response in plasma cells. Immunol Rev 2021; 303:35-51. [PMID: 34368957 DOI: 10.1111/imr.13012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 06/08/2021] [Indexed: 12/11/2022]
Abstract
The high rate of antibody production places considerable metabolic and folding stress on plasma cells (PC). Not surprisingly, they rely on the unfolded protein response (UPR), a universal signaling, and transcriptional network that monitors the health of the secretory pathway and mounts cellular responses to stress. Typically, the UPR utilizes three distinct stress sensors in the ER membrane, each regulating a subset of targets to re-establish homeostasis. PC use a specialized UPR scheme-they preemptively trigger the UPR via developmental signals and suppress two of the sensors, PERK and ATF6, relying on IRE1 alone. The specialized PC UPR program is tuned to the specific needs at every stage of development-from early biogenesis of secretory apparatus, to massive immunoglobulin expression later. Furthermore, the UPR in PC integrates with other pathways essential in a highly secretory cell-mTOR pathway that ensures efficient synthesis, autophagosomes that recycle components of the synthetic machinery, and apoptotic signaling that controls cell fate in the face of excessive folding stress. This specialized PC program is not shared with other secretory cells, for reasons yet to be defined. In this review, we give a perspective into how and why PC need such a unique UPR program.
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Affiliation(s)
- Daniela Ricci
- Department of Pathology and Lab Medicine, The Childrens' Hospital of Philadelphia and the University of Pennsylvania, Philadelphia, PA, USA
| | - Tali Gidalevitz
- Department of Biology, Drexel University, Philadelphia, PA, USA
| | - Yair Argon
- Department of Pathology and Lab Medicine, The Childrens' Hospital of Philadelphia and the University of Pennsylvania, Philadelphia, PA, USA
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24
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Endoplasmic Reticulum Stress in Diabetic Nephrology: Regulation, Pathological Role, and Therapeutic Potential. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:7277966. [PMID: 34394833 PMCID: PMC8355967 DOI: 10.1155/2021/7277966] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/29/2021] [Accepted: 07/17/2021] [Indexed: 12/20/2022]
Abstract
Recent progress has been made in understanding the roles and mechanisms of endoplasmic reticulum (ER) stress in the development and pathogenesis of diabetic nephropathy (DN). Hyperglycemia induces ER stress and apoptosis in renal cells. The induction of ER stress can be cytoprotective or cytotoxic. Experimental treatment of animals with ER stress inhibitors alleviated renal damage. Considering these findings, the normalization of ER stress by pharmacological agents is a promising approach to prevent or arrest DN progression. The current article reviews the mechanisms, roles, and therapeutic aspects of these findings.
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25
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Xue F, Lu J, Buchl SC, Sun L, Shah VH, Malhi H, Maiers JL. Coordinated signaling of activating transcription factor 6α and inositol-requiring enzyme 1α regulates hepatic stellate cell-mediated fibrogenesis in mice. Am J Physiol Gastrointest Liver Physiol 2021; 320:G864-G879. [PMID: 33728997 PMCID: PMC8202196 DOI: 10.1152/ajpgi.00453.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Liver injury and the unfolded protein response (UPR) are tightly linked, but their relationship differs with cell type and injurious stimuli. UPR initiation promotes hepatic stellate cell (HSC) activation and fibrogenesis, but the underlying mechanisms are unclear. Despite the complexity and overlap downstream of UPR transducers inositol-requiring protein 1α (IRE1α), activating transcription factor 6α (ATF6α), and protein kinase RNA-like ER kinase (PERK), previous research in HSCs primarily focused on IRE1α. Here, we investigated the fibrogenic role of ATF6α or PERK in vitro and HSC-specific UPR signaling in vivo. Overexpression of ATF6α, but not the PERK effector activating transcription factor 4 (ATF4), promoted HSC activation and fibrogenic gene transcription in immortalized HSCs. Furthermore, ATF6α inhibition through Ceapin-A7, or Atf6a deletion, disrupted transforming growth factor β (TGFβ)-mediated activation of primary human hepatic stellate cells (hHSCs) or murine hepatic stellate cells (mHSCs), respectively. We investigated the fibrogenic role of ATF6α in vivo through conditional HSC-specific Atf6a deletion. Atf6aHSCΔ/Δ mice displayed reduced fibrosis and HSC activation following bile duct ligation (BDL) or carbon tetrachloride (CCl4)-induced injury. The Atf6aHSCΔ/Δ phenotype differed from HSC-specific Ire1a deletion, as Ire1aHSCΔ/Δ mice showed reduced fibrogenic gene transcription but no changes in fibrosis compared with Ire1afl/fl mice following BDL. Interestingly, ATF6α signaling increased in Ire1aΔ/Δ HSCs, whereas IRE1α signaling was upregulated in Atf6aΔ/Δ HSCs. Finally, we asked whether co-deletion of Atf6a and Ire1a additively limits fibrosis. Unexpectedly, fibrosis worsened in Atf6aHSCΔ/ΔIre1aHSCΔ/Δ mice following BDL, and Atf6aΔ/ΔIre1aΔ/Δ mHSCs showed increased fibrogenic gene transcription. ATF6α and IRE1α individually promote fibrogenic transcription in HSCs, and ATF6α drives fibrogenesis in vivo. Unexpectedly, disruption of both pathways sensitizes the liver to fibrogenesis, suggesting that fine-tuned UPR signaling is critical for regulating HSC activation and fibrogenesis.NEW & NOTEWORTHY ATF6α is a critical driver of hepatic stellate cell (HSC) activation in vitro. HSC-specific deletion of Atf6a limits fibrogenesis in vivo despite increased IRE1α signaling. Conditional deletion of Ire1α from HSCs limits fibrogenic gene transcription without impacting overall fibrosis. This could be due in part to observed upregulation of the ATF6α pathway. Dual loss of Atf6a and Ire1a from HSCs worsens fibrosis in vivo through enhanced HSC activation.
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Affiliation(s)
- Fei Xue
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Jianwen Lu
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Samuel C. Buchl
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Liankang Sun
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Vijay H. Shah
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Harmeet Malhi
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Jessica L. Maiers
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
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Charbord J, Ren L, Sharma RB, Johansson A, Ågren R, Chu L, Tworus D, Schulz N, Charbord P, Stewart AF, Wang P, Alonso LC, Andersson O. In vivo screen identifies a SIK inhibitor that induces β cell proliferation through a transient UPR. Nat Metab 2021; 3:682-700. [PMID: 34031592 PMCID: PMC9756392 DOI: 10.1038/s42255-021-00391-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 04/14/2021] [Indexed: 02/03/2023]
Abstract
It is known that β cell proliferation expands the β cell mass during development and under certain hyperglycemic conditions in the adult, a process that may be used for β cell regeneration in diabetes. Here, through a new high-throughput screen using a luminescence ubiquitination-based cell cycle indicator (LUCCI) in zebrafish, we identify HG-9-91-01 as a driver of proliferation and confirm this effect in mouse and human β cells. HG-9-91-01 is an inhibitor of salt-inducible kinases (SIKs), and overexpression of Sik1 specifically in β cells blocks the effect of HG-9-91-01 on β cell proliferation. Single-cell transcriptomic analyses of mouse β cells demonstrate that HG-9-91-01 induces a wave of activating transcription factor (ATF)6-dependent unfolded protein response (UPR) before cell cycle entry. Importantly, the UPR wave is not associated with an increase in insulin expression. Additional mechanistic studies indicate that HG-9-91-01 induces multiple signalling effectors downstream of SIK inhibition, including CRTC1, CRTC2, ATF6, IRE1 and mTOR, which integrate to collectively drive β cell proliferation.
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Affiliation(s)
- Jérémie Charbord
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Lipeng Ren
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Rohit B Sharma
- Division of Endocrinology, Diabetes and Metabolism, Weill Cornell Medicine, New York, NY, USA
| | - Anna Johansson
- Department of Cell and Molecular Biology, National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Rasmus Ågren
- Department of Biology and Biological Engineering, National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Chalmers University of Technology, Göteborg, Sweden
| | - Lianhe Chu
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Dominika Tworus
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Nadja Schulz
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Pierre Charbord
- Sorbonne Université, Institut de Biologie Paris-Seine, CNRS UMR 7622, Inserm, Paris, France
| | - Andrew F Stewart
- Diabetes, Obesity, and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Peng Wang
- Diabetes, Obesity, and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Laura C Alonso
- Division of Endocrinology, Diabetes and Metabolism, Weill Cornell Medicine, New York, NY, USA
| | - Olov Andersson
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.
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27
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When Endoplasmic Reticulum Proteostasis Meets the DNA Damage Response. Trends Cell Biol 2020; 30:881-891. [PMID: 33036871 DOI: 10.1016/j.tcb.2020.09.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 08/31/2020] [Accepted: 09/07/2020] [Indexed: 02/06/2023]
Abstract
Sustaining both proteome and genome integrity (GI) requires the integration of a wide range of mechanisms and signaling pathways. These comprise, in particular, the unfolded protein response (UPR) and the DNA damage response (DDR). These adaptive mechanisms take place respectively in the endoplasmic reticulum (ER) and in the nucleus. UPR and DDR alterations are associated with aging and with pathologies such as degenerative diseases, metabolic and inflammatory disorders, and cancer. We discuss the emerging signaling crosstalk between UPR stress sensors and the DDR, as well as their involvement in cancer biology.
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