1
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Fasana E, Fregno I, Galli C, Soldà T, Molinari M. ER-to-lysosome-associated degradation acts as failsafe mechanism upon ERAD dysfunction. EMBO Rep 2024; 25:2773-2785. [PMID: 38773321 PMCID: PMC11169228 DOI: 10.1038/s44319-024-00165-y] [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: 03/01/2024] [Revised: 04/25/2024] [Accepted: 04/30/2024] [Indexed: 05/23/2024] Open
Abstract
The endoplasmic reticulum (ER) produces proteins destined to organelles of the endocytic and secretory pathways, the plasma membrane, and the extracellular space. While native proteins are transported to their intra- or extracellular site of activity, folding-defective polypeptides are retro-translocated across the ER membrane into the cytoplasm, poly-ubiquitylated and degraded by 26 S proteasomes in a process called ER-associated degradation (ERAD). Large misfolded polypeptides, such as polymers of alpha1 antitrypsin Z (ATZ) or mutant procollagens, fail to be dislocated across the ER membrane and instead enter ER-to-lysosome-associated degradation (ERLAD) pathways. Here, we show that pharmacological or genetic inhibition of ERAD components, such as the α1,2-mannosidase EDEM1 or the OS9 ERAD lectins triggers the delivery of the canonical ERAD clients Null Hong Kong (NHK) and BACE457Δ to degradative endolysosomes under control of the ER-phagy receptor FAM134B and the LC3 lipidation machinery. Our results reveal that ERAD dysfunction is compensated by the activation of FAM134B-driven ERLAD pathways that ensure efficient lysosomal clearance of orphan ERAD clients.
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Affiliation(s)
- Elisa Fasana
- Faculty of Biomedical Sciences, Institute for Research in Biomedicine, Università della Svizzera italiana (USI), 6500, Bellinzona, Switzerland
| | - Ilaria Fregno
- Faculty of Biomedical Sciences, Institute for Research in Biomedicine, Università della Svizzera italiana (USI), 6500, Bellinzona, Switzerland
| | - Carmela Galli
- Faculty of Biomedical Sciences, Institute for Research in Biomedicine, Università della Svizzera italiana (USI), 6500, Bellinzona, Switzerland
| | - Tatiana Soldà
- Faculty of Biomedical Sciences, Institute for Research in Biomedicine, Università della Svizzera italiana (USI), 6500, Bellinzona, Switzerland
| | - Maurizio Molinari
- Faculty of Biomedical Sciences, Institute for Research in Biomedicine, Università della Svizzera italiana (USI), 6500, Bellinzona, Switzerland.
- School of Life Sciences, École Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland.
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2
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Guo E, Yuan H, Li R, Yang J, Liu S, Liu A, Jiang X. Calcitriol ameliorates the progression of hepatic fibrosis through autophagy-related gene 16-like 1-mediated autophagy. Am J Med Sci 2024; 367:382-396. [PMID: 38431191 DOI: 10.1016/j.amjms.2024.02.010] [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: 11/29/2022] [Revised: 10/23/2023] [Accepted: 02/21/2024] [Indexed: 03/05/2024]
Abstract
BACKGROUND Calcitriol has the potential to counteract fibrotic diseases beyond its classical action of maintaining calcium and bone metabolism; however, its functional mechanism remains unknown. Autophagy-related gene 16-like 1 (Atg16l1) is one of the genes related to autophagy and is involved in protecting against fibrotic diseases. The present study aimed to explore the contribution of autophagy to the inhibition of calcitriol-induced hepatic fibrosis, as well as its potential molecular mechanism. METHODS Carbon tetrachloride (Ccl4)-treated mice were established as hepatic fibrosis models and received calcitriol treatment for 6 weeks. Quantification of Sirius red staining and measurement of key fibrotic markers (collagen-1 and α-SMA) was performed to detect hepatic fibrosis. Chloroquine (CQ) treatment was used to observe autophagic flux, and 3-methyladenine (3-MA) was used to inhibit autophagy. Furthermore, the effects of calcitriol on transforming growth factor β1 (TGFβ1)-stimulated primary hepatic stellate cells (HSCs) were detected. Downregulation of Atg16l1 or vitamin D receptor (VDR) in LX-2 cells was used to explore the mechanism of action of calcitriol in fibrosis and autophagy. Additionally, the electrophoretic mobility shift assay (EMSA) was used to investigate the interactions between VDR and ATG16L1. RESULTS Calcitriol increased the expression of VDR and ATG16L1, enhanced autophagy and attenuated hepatic fibrosis. 3-MA treatment and VDR silencing abolished the protective effects of calcitriol against fibrosis. Calcitriol-induced anti-fibrosis effects were blocked by ATG16L1 suppression. Furthermore, VDR bound to the ATG16L1 promoter and downregulation of VDR decreased the expression of ATG16L1 in LX-2 cells. CONCLUSION Calcitriol mitigates hepatic fibrosis partly through ATG16L1-mediated autophagy.
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Affiliation(s)
- Enshuang Guo
- Experimental Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Department of Infectious Diseases, General Hospital of Central Theater Command of PLA, Wuhan 430070, China; Department of Infectious Diseases, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Huixing Yuan
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Renlong Li
- Department of Infectious Diseases, General Hospital of Central Theater Command of PLA, Wuhan 430070, China; Southern Medical University, Guangzhou 510515, China
| | - Jiankun Yang
- Experimental Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Shenpei Liu
- Experimental Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Anding Liu
- Experimental Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
| | - Xiaojing Jiang
- Department of Infectious Diseases, General Hospital of Central Theater Command of PLA, Wuhan 430070, China; Southern Medical University, Guangzhou 510515, China
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3
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Wang Y, Ping Z, Gao H, Liu Z, Xv Q, Jiang X, Yu W. LYC inhibits the AKT signaling pathway to activate autophagy and ameliorate TGFB-induced renal fibrosis. Autophagy 2024; 20:1114-1133. [PMID: 38037248 PMCID: PMC11135866 DOI: 10.1080/15548627.2023.2287930] [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: 04/10/2023] [Accepted: 11/20/2023] [Indexed: 12/02/2023] Open
Abstract
Renal fibrosis is a typical pathological change in chronic kidney disease (CKD). Epithelial-mesenchymal transition (EMT) is the predominant stage. Activation of macroautophagy/autophagy plays a crucial role in the process of EMT. Lycopene (LYC) is a highly antioxidant carotenoid with pharmacological effects such as anti-inflammation, anti-apoptosis and mediation of autophagy. In this study, we demonstrated the specific mechanism of LYC in activating mitophagy and improving renal fibrosis. The enrichment analysis results of GO and KEGG showed that LYC had high enrichment values with autophagy. In this study, we showed that LYC alleviated aristolochic acid I (AAI)-induced intracellular expression of PINK1, TGFB/TGF-β, p-SMAD2, p-SMAD3, and PRKN/Parkin, recruited expression of MAP1LC3/LC3-II and SQSTM1/p62, decreased mitochondrial membrane potential (MMP), and ameliorated renal fibrosis in mice. When we simultaneously intervened NRK52E cells using bafilomycin A1 (Baf-A1), AAI, and LYC, intracellular MAP1LC3-II and SQSTM1 expression was significantly increased. A similar result was seen in renal tissue and cells when treated in vitro and in vivo with CQ, AAI, and LYC, and the inhibitory effect of LYC on the AAI-activated SMAD2-SMAD3 signaling pathway was attenuated. Molecular docking simulation experiments showed that LYC stably bound to the AKT active site. After intervention of cells with AAI and GSK-690693, the expression of PINK1, PRKN, MAP1LC3-II, BECN1, p-SMAD2 and p-SMAD3 was increased, and the expression of SQSTM1 was decreased. However, SC79 inhibited autophagy and reversed the inhibitory effect of LYC on EMT. The results showed that LYC could inhibit the AKT signaling pathway to activate mitophagy and reduce renal fibrosis.Abbreviation: AA: aristolochic acid; ACTA2/α-SMA: actin alpha 2, smooth muscle, aorta; ACTB: actin beta; AKT/protein kinase B: thymoma viral proto-oncogene; BAF-A1: bafilomycin A1; BECN1: beclin 1, autophagy related; CCN2/CTGF: cellular communication network factor 2; CDH1/E-Cadherin: cadherin 1; CKD: chronic kidney disease; COL1: collagen, type I; COL3: collagen, type III; CQ: chloroquine; ECM: extracellular matrix; EMT: epithelial-mesenchymal transition; FN1: fibronectin 1; LYC: lycopene; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MMP: mitochondrial membrane potential; MTOR: mechanistic target of rapamycin kinase ; PI3K: phosphoinositide 3-kinase; PINK1: PTEN induced putative kinase 1; PRKN/Parkin: parkin RBR E3 ubiquitin protein ligase; PPI: protein-protein interaction; SMAD2: SMAD family member 2; SMAD3: SMAD family member 3; SQSTM1/p62: sequestosome 1; TGFB/TGFβ: transforming growth factor, beta; VIM: vimentin.
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Affiliation(s)
- Yu Wang
- Department of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Zhenlei Ping
- Department of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Hongxin Gao
- Department of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Zhihui Liu
- Department of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Qingyang Xv
- Department of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Xiaowen Jiang
- Department of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Wenhui Yu
- Department of Veterinary Medicine, Northeast Agricultural University, Harbin, China
- Institute of Chinese Veterinary Medicine, Northeast Agricultural University, Harbin, China
- Key Laboratory of Animal Pathogenesis and Comparative Medicine in Heilongjiang Province, Northeast Agricultural University, Harbin, China
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4
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Saadh MJ, Mahdi MS, Allela OQB, Alazzawi TS, Ubaid M, Rakhimov NM, Athab ZH, Ramaiah P, Chinnasamy L, Alsaikhan F, Farhood B. Critical role of miR-21/exosomal miR-21 in autophagy pathway. Pathol Res Pract 2024; 257:155275. [PMID: 38643552 DOI: 10.1016/j.prp.2024.155275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Revised: 03/22/2024] [Accepted: 03/26/2024] [Indexed: 04/23/2024]
Abstract
Activation of autophagy, a process of cellular stress response, leads to the breakdown of proteins, organelles, and other parts of the cell in lysosomes, and can be linked to several ailments, such as cancer, neurological diseases, and rare hereditary syndromes. Thus, its regulation is very carefully monitored. Transcriptional and post-translational mechanisms domestically or in whole organisms utilized to control the autophagic activity, have been heavily researched. In modern times, microRNAs (miRNAs) are being considered to have a part in post-translational orchestration of the autophagic activity, with miR-21 as one of the best studied miRNAs, it is often more than expressed in cancer cells. This regulatory RNA is thought to play a major role in a plethora of processes and illnesses including growth, cancer, cardiovascular disease, and inflammation. Different studies have suggested that a few autophagy-oriented genes, such as PTEN, Rab11a, Atg12, SIPA1L2, and ATG5, are all targeted by miR-21, indicating its essential role in the regulation.
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Affiliation(s)
- Mohamed J Saadh
- Faculty of Pharmacy, Middle East University, Amman 11831, Jordan
| | | | | | - Tuqa S Alazzawi
- College of dentist, National University of Science and Technology, Dhi Qar, Iraq
| | | | - Nodir M Rakhimov
- Department of Oncology, Samarkand State Medical University, 18 Amir Temur Street, Samarkand, Uzbekistan; Department of Oncology, Tashkent State Dental Institute, Tashkent, Uzbekistan
| | - Zainab H Athab
- Department of Pharmacy, Al-Zahrawi University College, Karbala, Iraq
| | | | | | - Fahad Alsaikhan
- College of Pharmacy, Prince Sattam Bin Abdulaziz University, Alkharj, Saudi Arabia jSchool of Pharmacy, Ibn Sina National College for Medical Studies, Jeddah, Saudi Arabia.
| | - Bagher Farhood
- Department of Medical Physics and Radiology, Faculty of Paramedical Sciences, Kashan University of Medical Sciences, Kashan, Iran.
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5
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Tan WH, Rücklin M, Larionova D, Ngoc TB, Joan van Heuven B, Marone F, Matsudaira P, Winkler C. A Collagen10a1 mutation disrupts cell polarity in a medaka model for metaphyseal chondrodysplasia type Schmid. iScience 2024; 27:109405. [PMID: 38510140 PMCID: PMC10952040 DOI: 10.1016/j.isci.2024.109405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 12/21/2023] [Accepted: 02/29/2024] [Indexed: 03/22/2024] Open
Abstract
Heterozygous mutations in COL10A1 lead to metaphyseal chondrodysplasia type Schmid (MCDS), a skeletal disorder characterized by epiphyseal abnormalities. Prior analysis revealed impaired trimerization and intracellular retention of mutant collagen type X alpha 1 chains as cause for elevated endoplasmic reticulum (ER) stress. However, how ER stress translates into structural defects remained unclear. We generated a medaka (Oryzias latipes) MCDS model harboring a 5 base pair deletion in col10a1, which led to a frameshift and disruption of 11 amino acids in the conserved trimerization domain. col10a1Δ633a heterozygotes recapitulated key features of MCDS and revealed early cell polarity defects as cause for dysregulated matrix secretion and deformed skeletal structures. Carbamazepine, an ER stress-reducing drug, rescued this polarity impairment and alleviated skeletal defects in col10a1Δ633a heterozygotes. Our data imply cell polarity dysregulation as a potential contributor to MCDS and suggest the col10a1Δ633a medaka mutant as an attractive MCDS animal model for drug screening.
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Affiliation(s)
- Wen Hui Tan
- Department of Biological Sciences and Centre for Bioimaging Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Martin Rücklin
- Naturalis Biodiversity Center, Postbus 9517, 2300 RA Leiden, the Netherlands
| | - Daria Larionova
- Department of Biology, Research Group Evolutionary Developmental Biology, Ghent University, Ghent, Belgium
| | - Tran Bich Ngoc
- Department of Biological Sciences and Centre for Bioimaging Sciences, National University of Singapore, Singapore 117543, Singapore
| | | | - Federica Marone
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Paul Matsudaira
- Department of Biological Sciences and Centre for Bioimaging Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Christoph Winkler
- Department of Biological Sciences and Centre for Bioimaging Sciences, National University of Singapore, Singapore 117543, Singapore
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6
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Zhao P, Wang C, Sun S, Wang X, Balch WE. Tracing genetic diversity captures the molecular basis of misfolding disease. Nat Commun 2024; 15:3333. [PMID: 38637533 PMCID: PMC11026414 DOI: 10.1038/s41467-024-47520-0] [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: 04/04/2023] [Accepted: 04/04/2024] [Indexed: 04/20/2024] Open
Abstract
Genetic variation in human populations can result in the misfolding and aggregation of proteins, giving rise to systemic and neurodegenerative diseases that require management by proteostasis. Here, we define the role of GRP94, the endoplasmic reticulum Hsp90 chaperone paralog, in managing alpha-1-antitrypsin deficiency on a residue-by-residue basis using Gaussian process regression-based machine learning to profile the spatial covariance relationships that dictate protein folding arising from sequence variants in the population. Covariance analysis suggests a role for the ATPase activity of GRP94 in controlling the N- to C-terminal cooperative folding of alpha-1-antitrypsin responsible for the correction of liver aggregation and lung-disease phenotypes of alpha-1-antitrypsin deficiency. Gaussian process-based spatial covariance profiling provides a standard model built on covariant principles to evaluate the role of proteostasis components in guiding information flow from genome to proteome in response to genetic variation, potentially allowing us to intervene in the onset and progression of complex multi-system human diseases.
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Affiliation(s)
- Pei Zhao
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
| | - Chao Wang
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA.
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, China.
| | - Shuhong Sun
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
- Department of Nutrition and Food Hygiene, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
- Institute for Brain Tumors, Collaborative Innovation Center for Cancer Personalized Medicine, and Center for Global Health, Nanjing Medical University, Nanjing, China
| | - Xi Wang
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - William E Balch
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA.
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7
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Dasí F. Alpha-1 antitrypsin deficiency. Med Clin (Barc) 2024; 162:336-342. [PMID: 37993348 DOI: 10.1016/j.medcli.2023.10.014] [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: 07/27/2023] [Revised: 10/21/2023] [Accepted: 10/24/2023] [Indexed: 11/24/2023]
Abstract
Alpha-1 antitrypsin deficiency (AATD) is a rare hereditary condition caused by decreased plasma and tissue levels of alpha-1 antitrypsin (AAT) that can lead to serious lung and liver disease in children and adults. AATD patients face challenges such as under diagnosis, clinical variability, and limited treatment options for liver disease. Early detection and biomarkers for predicting outcomes are needed to improve patient outcome. Currently, the only approved pharmacological therapy is augmentation therapy, which can delay the progression of emphysema. However, alternative strategies such as gene therapy, induced pluripotent stem cells, and prevention of AAT polymerization inside hepatocytes are being investigated. This review aims to summarize and update current knowledge on AATD, identify areas of controversy, and formulate questions for further research.
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Affiliation(s)
- Francisco Dasí
- Universitat de València, Facultad de Medicina, Departamento de Fisiología, IIS INCLIVA, Valencia, Spain.
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8
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Tafaleng EN, Li J, Wang Y, Hidvegi T, Soto-Gutierrez A, Locke AE, Nicholas TJ, Wang YC, Pak S, Cho MH, Silverman EK, Silverman GA, Jin SC, Fox IJ, Perlmutter DH. Variants in autophagy genes MTMR12 and FAM134A are putative modifiers of the hepatic phenotype in α1-antitrypsin deficiency. Hepatology 2024:01515467-990000000-00833. [PMID: 38557779 DOI: 10.1097/hep.0000000000000865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 02/26/2024] [Indexed: 04/04/2024]
Abstract
BACKGROUND AND AIMS In the classical form of α1-antitrypsin deficiency, a misfolded variant α1-antitrypsin Z accumulates in the endoplasmic reticulum of liver cells and causes liver cell injury by gain-of-function proteotoxicity in a sub-group of affected homozygotes but relatively little is known about putative modifiers. Here, we carried out genomic sequencing in a uniquely affected family with an index case of liver failure and 2 homozygous siblings with minimal or no liver disease. Their sequences were compared to sequences in well-characterized cohorts of homozygotes with or without liver disease, and then candidate sequence variants were tested for changes in the kinetics of α1-antitrypsin variant Z degradation in iPS-derived hepatocyte-like cells derived from the affected siblings themselves. APPROACH AND RESULTS Specific variants in autophagy genes MTMR12 and FAM134A could each accelerate the degradation of α1-antitrypsin variant Z in cells from the index patient, but both MTMR12 and FAM134A variants were needed to slow the degradation of α1-antitrypsin variant Z in cells from a protected sib, indicating that inheritance of both variants is needed to mediate the pathogenic effects of hepatic proteotoxicity at the cellular level. Analysis of homozygote cohorts showed that multiple patient-specific variants in proteostasis genes are likely to explain liver disease susceptibility at the population level. CONCLUSIONS These results validate the concept that genetic variation in autophagy function can determine susceptibility to liver disease in α1-antitrypsin deficiency and provide evidence that polygenic mechanisms and multiple patient-specific variants are likely needed for proteotoxic pathology.
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Affiliation(s)
- Edgar N Tafaleng
- Departments of Pediatrics, Surgery and Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jie Li
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Yan Wang
- Departments of Pediatrics, Surgery and Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Tunda Hidvegi
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Alex Soto-Gutierrez
- Departments of Pediatrics, Surgery and Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Adam E Locke
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Thomas J Nicholas
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Yung-Chun Wang
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Stephen Pak
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Michael H Cho
- Channing Laboratories, Harvard Medical School, Boston, Massachusetts, USA
| | - Edwin K Silverman
- Channing Laboratories, Harvard Medical School, Boston, Massachusetts, USA
| | - Gary A Silverman
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Sheng Chih Jin
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Ira J Fox
- Departments of Pediatrics, Surgery and Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - David H Perlmutter
- Departments of Pediatrics, Cell Biology and Physiology, Genetics and McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
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9
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Roberts BS, Mitra D, Abishek S, Beher R, Satpute-Krishnan P. The p24-family and COPII subunit SEC24C facilitate the clearance of alpha1-antitrypsin Z from the endoplasmic reticulum to lysosomes. Mol Biol Cell 2024; 35:ar45. [PMID: 38294851 PMCID: PMC10916869 DOI: 10.1091/mbc.e23-06-0257] [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: 07/03/2023] [Revised: 01/16/2024] [Accepted: 01/24/2024] [Indexed: 02/01/2024] Open
Abstract
A subpopulation of the alpha-1-antitrypsin misfolding Z mutant (ATZ) is cleared from the endoplasmic reticulum (ER) via an ER-to-lysosome-associated degradation (ERLAD) pathway. Here, we report that the COPII subunit SEC24C and the p24-family of proteins facilitate the clearance of ATZ via ERLAD. In addition to the previously reported ERLAD components calnexin and FAM134B, we discovered that ATZ coimmunoprecipitates with the p24-family members TMP21 and TMED9. This contrasts with wild type alpha1-antitrypsin, which did not coimmunoprecipitate with FAM134B, calnexin or the p24-family members. Live-cell imaging revealed that ATZ and the p24-family members traffic together from the ER to lysosomes. Using chemical inhibitors to block ER exit or autophagy, we demonstrated that p24-family members and ATZ co-accumulate at SEC24C marked ER-exit sites or in ER-derived compartments, respectively. Furthermore, depletion of SEC24C, TMP21, or TMED9 inhibited lysosomal trafficking of ATZ and resulted in the increase of intracellular ATZ levels. Conversely, overexpression of these p24-family members resulted in the reduction of ATZ levels. Intriguingly, the p24-family members coimmunoprecipitate with ATZ, FAM134B, and SEC24C. Thus, we propose a model in which the p24-family functions in an adaptor complex linking SEC24C with the ERLAD machinery for the clearance of ATZ.
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Affiliation(s)
| | - Debashree Mitra
- Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Sudhanshu Abishek
- Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Richa Beher
- Uniformed Services University of the Health Sciences, Bethesda, MD 20814
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10
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Galetaki DM, Merchant N, Dauber A. Novel therapies for growth disorders. Eur J Pediatr 2024; 183:1121-1128. [PMID: 37831302 DOI: 10.1007/s00431-023-05239-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 09/21/2023] [Accepted: 09/22/2023] [Indexed: 10/14/2023]
Abstract
As we continue to understand more about the complex mechanism of growth, a plethora of novel therapies have recently been developed that aim to address barriers and optimize efficacy. This review aims to explore these novel therapies and provide a succinct review based on the latest clinical studies in order to introduce clinicians to therapies that will soon constitute the future in the field of short stature. Conclusion: The review focuses on long-acting growth hormone formulations, a novel growth hormone oral secretagogue, novel treatments for children with achondroplasia, and targeted therapies for rare forms of skeletal dysplasias. What is Known: • Recombinant human growth hormone has been the mainstay of treatment for children with short stature for years. • Such therapy is not always effective based on the underlying diagnosis (e.g achondroplasia, Turner syndrome). Compliance with daily injections is challenging and can directly affect efficacy. What is New: • Recent development of long-acting growth hormone regimens and oral secretagogues can overcome some of these barriers, however several limitations need to be taken into consideration. • Newer therapies for achondroplasia, and other rare forms of skeletal dysplasias introduce us to a new era of targeted therapies for children with short stature. Clinicians ought to be aware of pitfalls and caveats before introducing these novel therapies to every day practice.
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Affiliation(s)
- Despoina M Galetaki
- Division of Endocrinology, Children's National Hospital, Washington, DC, USA
| | - Nadia Merchant
- Division of Endocrinology, Children's National Hospital, Washington, DC, USA
- Department of Pediatrics, George Washington School of Medicine, Washington, DC, USA
| | - Andrew Dauber
- Division of Endocrinology, Children's National Hospital, Washington, DC, USA.
- Department of Pediatrics, George Washington School of Medicine, Washington, DC, USA.
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11
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Li J, Moretti F, Hidvegi T, Sviben S, Fitzpatrick JAJ, Sundaramoorthi H, Pak SC, Silverman GA, Knapp B, Filipuzzi I, Alford J, Reece-Hoyes J, Nigsch F, Murphy LO, Nyfeler B, Perlmutter DH. Multiple Genes Core to ERAD, Macroautophagy and Lysosomal Degradation Pathways Participate in the Proteostasis Response in α1-Antitrypsin Deficiency. Cell Mol Gastroenterol Hepatol 2024; 17:1007-1024. [PMID: 38336172 PMCID: PMC11053228 DOI: 10.1016/j.jcmgh.2024.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 02/05/2024] [Accepted: 02/05/2024] [Indexed: 02/12/2024]
Abstract
BACKGROUND & AIMS In the classic form of α1-antitrypsin deficiency (ATD), the misfolded α1-antitrypsin Z (ATZ) variant accumulates in the endoplasmic reticulum (ER) of liver cells. A gain-of-function proteotoxic mechanism is responsible for chronic liver disease in a subgroup of homozygotes. Proteostatic response pathways, including conventional endoplasmic reticulum-associated degradation and autophagy, have been proposed as the mechanisms that allow cellular adaptation and presumably protection from the liver disease phenotype. Recent studies have concluded that a distinct lysosomal pathway called endoplasmic reticulum-to-lysosome completely supplants the role of the conventional macroautophagy pathway in degradation of ATZ. Here, we used several state-of-the-art approaches to characterize the proteostatic responses more fully in cellular systems that model ATD. METHODS We used clustered regularly interspaced short palindromic repeats (CRISPR)-mediated genome editing coupled to a cell selection step by fluorescence-activated cell sorter to perform screening for proteostasis genes that regulate ATZ accumulation and combined that with selective genome editing in 2 other model systems. RESULTS Endoplasmic reticulum-associated degradation genes are key early regulators and multiple autophagy genes, from classic as well as from ER-to-lysosome and other newly described ER-phagy pathways, participate in degradation of ATZ in a manner that is temporally regulated and evolves as ATZ accumulation persists. Time-dependent changes in gene expression are accompanied by specific ultrastructural changes including dilation of the ER, formation of globular inclusions, budding of autophagic vesicles, and alterations in the overall shape and component parts of mitochondria. CONCLUSIONS Macroautophagy is a critical component of the proteostasis response to cellular ATZ accumulation and it becomes more important over time as ATZ synthesis continues unabated. Multiple subtypes of macroautophagy and nonautophagic lysosomal degradative pathways are needed to respond to the high concentrations of misfolded protein that characterizes ATD and these pathways are attractive candidates for genetic variants that predispose to the hepatic phenotype.
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Affiliation(s)
- Jie Li
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | | | - Tunda Hidvegi
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Sanja Sviben
- Center for Cellular Imaging, Washington University School of Medicine, St. Louis, Missouri
| | - James A J Fitzpatrick
- Center for Cellular Imaging, Washington University School of Medicine, St. Louis, Missouri; Department of Cell Biology, Washington University School of Medicine, St. Louis, Missouri; Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri
| | | | - Stephen C Pak
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Gary A Silverman
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Britta Knapp
- Novartis Biomedical Research, Basel, Switzerland
| | | | - John Alford
- Novartis Biomedical Research, Cambridge, Massachusetts
| | | | | | - Leon O Murphy
- Novartis Biomedical Research, Cambridge, Massachusetts
| | - Beat Nyfeler
- Novartis Biomedical Research, Basel, Switzerland
| | - David H Perlmutter
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri.
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12
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Lee SW, Oh YM, Victor MB, Yang Y, Chen S, Strunilin I, Dahiya S, Dolle RE, Pak SC, Silverman GA, Perlmutter DH, Yoo AS. Longitudinal modeling of human neuronal aging reveals the contribution of the RCAN1-TFEB pathway to Huntington's disease neurodegeneration. NATURE AGING 2024; 4:95-109. [PMID: 38066314 DOI: 10.1038/s43587-023-00538-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 11/03/2023] [Indexed: 12/19/2023]
Abstract
Aging is a common risk factor in neurodegenerative disorders. Investigating neuronal aging in an isogenic background stands to facilitate analysis of the interplay between neuronal aging and neurodegeneration. Here we perform direct neuronal reprogramming of longitudinally collected human fibroblasts to reveal genetic pathways altered at different ages. Comparative transcriptome analysis of longitudinally aged striatal medium spiny neurons (MSNs) in Huntington's disease identified pathways involving RCAN1, a negative regulator of calcineurin. Notably, RCAN1 protein increased with age in reprogrammed MSNs as well as in human postmortem striatum and RCAN1 knockdown rescued patient-derived MSNs of Huntington's disease from degeneration. RCAN1 knockdown enhanced chromatin accessibility of genes involved in longevity and autophagy, mediated through enhanced calcineurin activity, leading to TFEB's nuclear localization by dephosphorylation. Furthermore, G2-115, an analog of glibenclamide with autophagy-enhancing activities, reduced the RCAN1-calcineurin interaction, phenocopying the effect of RCAN1 knockdown. Our results demonstrate that targeting RCAN1 genetically or pharmacologically can increase neuronal resilience in Huntington's disease.
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Affiliation(s)
- Seong Won Lee
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Sciences, Mercer University School of Medicine, Columbus, GA, USA
| | - Young Mi Oh
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Sciences, Mercer University School of Medicine, Columbus, GA, USA
| | - Matheus B Victor
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yan Yang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Shawei Chen
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ilya Strunilin
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Sonika Dahiya
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Roland E Dolle
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
| | - Stephen C Pak
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Gary A Silverman
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - David H Perlmutter
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Andrew S Yoo
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
- Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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13
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Picca A, Faitg J, Auwerx J, Ferrucci L, D'Amico D. Mitophagy in human health, ageing and disease. Nat Metab 2023; 5:2047-2061. [PMID: 38036770 DOI: 10.1038/s42255-023-00930-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 10/13/2023] [Indexed: 12/02/2023]
Abstract
Maintaining optimal mitochondrial function is a feature of health. Mitophagy removes and recycles damaged mitochondria and regulates the biogenesis of new, fully functional ones preserving healthy mitochondrial functions and activities. Preclinical and clinical studies have shown that impaired mitophagy negatively affects cellular health and contributes to age-related chronic diseases. Strategies to boost mitophagy have been successfully tested in model organisms, and, recently, some have been translated into clinics. In this Review, we describe the basic mechanisms of mitophagy and how mitophagy can be assessed in human blood, the immune system and tissues, including muscle, brain and liver. We outline mitophagy's role in specific diseases and describe mitophagy-activating approaches successfully tested in humans, including exercise and nutritional and pharmacological interventions. We describe how mitophagy is connected to other features of ageing through general mechanisms such as inflammation and oxidative stress and forecast how strengthening research on mitophagy and mitophagy interventions may strongly support human health.
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Affiliation(s)
- Anna Picca
- Department of Medicine and Surgery, LUM University, Casamassima, Italy
- Fondazione Policlinico Universitario 'A. Gemelli' IRCCS, Rome, Italy
| | - Julie Faitg
- Amazentis, EPFL Innovation Park, Lausanne, Switzerland
| | - Johan Auwerx
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Luigi Ferrucci
- Division of Intramural Research, National Institute on Aging, Baltimore, MD, USA.
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14
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Knupp J, Pletan ML, Arvan P, Tsai B. Autophagy of the ER: the secretome finds the lysosome. FEBS J 2023; 290:5656-5673. [PMID: 37920925 PMCID: PMC11044768 DOI: 10.1111/febs.16986] [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: 08/03/2023] [Revised: 09/20/2023] [Accepted: 10/23/2023] [Indexed: 11/04/2023]
Abstract
Lysosomal degradation of the endoplasmic reticulum (ER) and its components through the autophagy pathway has emerged as a major regulator of ER proteostasis. Commonly referred to as ER-phagy and ER-to-lysosome-associated degradation (ERLAD), how the ER is targeted to the lysosome has been recently clarified by a growing number of studies. Here, we summarize the discoveries of the molecular components required for lysosomal degradation of the ER and their proposed mechanisms of action. Additionally, we discuss how cells employ these machineries to create the different routes of ER-lysosome-associated degradation. Further, we review the role of ER-phagy in viral infection pathways, as well as the implication of ER-phagy in human disease. In sum, we provide a comprehensive overview of the current field of ER-phagy.
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Affiliation(s)
- Jeffrey Knupp
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Madison L Pletan
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Peter Arvan
- Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Billy Tsai
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA
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15
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Yang Y, Yuan R, Lu Y, Zhu C, Zhang C, Lue H, Zhang X. The engagement of autophagy in maniac disease. CNS Neurosci Ther 2023; 29:3684-3692. [PMID: 37438945 PMCID: PMC10651947 DOI: 10.1111/cns.14353] [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: 12/17/2022] [Revised: 06/16/2023] [Accepted: 06/30/2023] [Indexed: 07/14/2023] Open
Abstract
AIMS Mania is a prevalent psychiatric disorder with undefined pathological mechanism. Here, we reviewed current knowledge indicating the potential involvement of autophagy dysregulation in mania and further discussed whether targeting autophagy could be a promising strategy for mania therapy. DISCUSSIONS Accumulating evidence indicated the involvement of autophagy in the pathology of mania. One of the most well-accepted mechanisms underlying mania, circadian dysregulation, showed mutual interaction with autophagy dysfunction. In addition, several first-line drugs for mania therapy were found to regulate neuronal autophagy. Besides, deficiencies in mitochondrial quality control, neurotransmission, and ion channel, which showed causal links to mania, were intimately associated with autophagy dysfunction. CONCLUSIONS Although more efforts should be made to either identify the key pathology of mania, the current evidence supported that autophagy dysregulation may act as a possible mechanism involved in the onset of mania-like symptoms. It is therefore a potential strategy to treat manic disorder by correting autophagy.
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Affiliation(s)
- Yidong Yang
- Institute of Pharmacology & Toxicology, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
| | - Renxiang Yuan
- Institute of Pharmacology & Toxicology, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
| | - Yangyang Lu
- Institute of Pharmacology & Toxicology, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
| | - Chenze Zhu
- Institute of Pharmacology & Toxicology, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
| | - Chen Zhang
- Institute of Pharmacology & Toxicology, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
| | - Haifeng Lue
- School of PharmacyHangzhou Medical CollegeHangzhouChina
| | - Xiangnan Zhang
- Institute of Pharmacology & Toxicology, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
- Jinhua Institute of Zhejiang UniversityJinhuaChina
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16
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Wu T, Hagiwara M, Gnass E, Barman H, Sasson D, Treem W, Ren K, Marins EG, Karki C, Malhi H. Liver disease progression in patients with alpha-1 antitrypsin deficiency and protease inhibitor ZZ genotype with or without lung disease. Aliment Pharmacol Ther 2023; 58:1075-1085. [PMID: 37718576 DOI: 10.1111/apt.17715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/09/2023] [Accepted: 08/30/2023] [Indexed: 09/19/2023]
Abstract
BACKGROUND Alpha-1 antitrypsin deficiency (AATD) is caused by mutations in SERPINA1, which encodes alpha-1 antitrypsin, a protease inhibitor (Pi). Individuals with AATD and the homozygous Pi*ZZ genotype have variable risk of progressive liver disease but the influence of comorbid lung disease is poorly understood. AIMS To characterise patients with AATD Pi*ZZ and liver disease (AATD-LD-Pi*ZZ) with or without lung disease and describe liver disease-related clinical events longitudinally. METHODS This was an observational cohort study of patients in the Mayo Clinic Healthcare System (January 2000-September 2021). Patients were identified using diagnosis codes and natural language processing. Fibrosis stage (F0-F4) was assessed using a hierarchical approach at baseline (90 days before or after the index date) and follow-up. Clinical events associated with liver disease progression were assessed. RESULTS AATD-LD-Pi*ZZ patients with lung disease had a longer median time from AATD diagnosis to liver disease diagnosis versus those without lung disease (2.2 vs. 0.2 years, respectively). Compared to those without lung disease, patients with lung disease had a longer time to liver disease-related clinical events (8.5 years and not reached, respectively). AATD-LD-Pi*ZZ patients without lung disease were more likely to undergo liver transplantation compared with those with lung disease. CONCLUSION In patients with AATD and lung disease, there is a delay in the diagnosis of comorbid liver disease. Our findings suggest that liver disease may progress more rapidly in patients without comorbid lung disease.
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Affiliation(s)
- Tiffany Wu
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
| | - May Hagiwara
- Takeda Development Center Americas, Inc., Lexington, Massachusetts, USA
| | | | | | | | - William Treem
- Takeda Development Center Americas, Inc., Lexington, Massachusetts, USA
| | - Kaili Ren
- Takeda Development Center Americas, Inc., Lexington, Massachusetts, USA
| | - Ed G Marins
- Takeda Development Center Americas, Inc., Lexington, Massachusetts, USA
| | - Chitra Karki
- Takeda Development Center Americas, Inc., Lexington, Massachusetts, USA
| | - Harmeet Malhi
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
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17
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Abreu N, Pereira VM, Pestana M, Jasmins L. Future Perspectives in the Diagnosis and Treatment of Liver Disease Associated with Alpha-1 Antitrypsin Deficiency. GE PORTUGUESE JOURNAL OF GASTROENTEROLOGY 2023; 30:327-335. [PMID: 37868641 PMCID: PMC10586215 DOI: 10.1159/000528809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 11/15/2022] [Indexed: 10/24/2023]
Abstract
Alpha-1 antitrypsin deficiency (AATD) is one of the most common genetic diseases and is caused by mutations in the SERPINA1 gene. The homozygous Pi*Z variant is responsible for the majority of the classic severe form of alpha-1 antitrypsin deficiency, which is characterized by markedly decreased levels of serum alpha-1 antitrypsin (AAT) with a strong predisposition to lung and liver disease. The diagnosis and early treatment of AATD-associated liver disease are challenges in clinical practice. In this review, the authors aim to summarize the current evidence of the non-invasive methods in the assessment of liver fibrosis, as well as to elucidate the main therapeutic strategies under investigation that may emerge in the near future.
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Affiliation(s)
- Nélia Abreu
- Department of Gastroenterology, Hospital Central Do Funchal, Madeira, Portugal
| | - Vítor Magno Pereira
- Department of Gastroenterology, Hospital Central Do Funchal, Madeira, Portugal
| | - Madalena Pestana
- Department of Gastroenterology, Hospital Central Do Funchal, Madeira, Portugal
| | - Luís Jasmins
- Department of Gastroenterology, Hospital Central Do Funchal, Madeira, Portugal
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18
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Shreya S, Grosset CF, Jain BP. Unfolded Protein Response Signaling in Liver Disorders: A 2023 Updated Review. Int J Mol Sci 2023; 24:14066. [PMID: 37762367 PMCID: PMC10531763 DOI: 10.3390/ijms241814066] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/04/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
Endoplasmic reticulum (ER) is the site for synthesis and folding of secreted and transmembrane proteins. Disturbance in the functioning of ER leads to the accumulation of unfolded and misfolded proteins, which finally activate the unfolded protein response (UPR) signaling. The three branches of UPR-IRE1 (Inositol requiring enzyme 1), PERK (Protein kinase RNA-activated (PKR)-like ER kinase), and ATF6 (Activating transcription factor 6)-modulate the gene expression pattern through increased expression of chaperones and restore ER homeostasis by enhancing ER protein folding capacity. The liver is a central organ which performs a variety of functions which help in maintaining the overall well-being of our body. The liver plays many roles in cellular physiology, blood homeostasis, and detoxification, and is the main site at which protein synthesis occurs. Disturbance in ER homeostasis is triggered by calcium level imbalance, change in redox status, viral infection, and so on. ER dysfunction and subsequent UPR signaling participate in various hepatic disorders like metabolic (dysfunction) associated fatty liver disease, liver cancer, viral hepatitis, and cholestasis. The exact role of ER stress and UPR signaling in various liver diseases is not fully understood and needs further investigation. Targeting UPR signaling with drugs is the subject of intensive research for therapeutic use in liver diseases. The present review summarizes the role of UPR signaling in liver disorders and describes why UPR regulators are promising therapeutic targets.
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Affiliation(s)
- Smriti Shreya
- Gene Expression and Signaling Lab, Department of Zoology, Mahatma Gandhi Central University, Motihari 845401, Bihar, India;
| | - Christophe F. Grosset
- MIRCADE Team, U1312, Bordeaux Institute in Oncology, BRIC, Université de Bordeaux, 146 Rue Léo Saignat, F-33000 Bordeaux, France
| | - Buddhi Prakash Jain
- Gene Expression and Signaling Lab, Department of Zoology, Mahatma Gandhi Central University, Motihari 845401, Bihar, India;
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19
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Pastore N, Annunziata F, Colonna R, Maffia V, Giuliano T, Custode BM, Lombardi B, Polishchuk E, Cacace V, De Stefano L, Nusco E, Sorrentino NC, Piccolo P, Brunetti-Pierri N. Increased expression or activation of TRPML1 reduces hepatic storage of toxic Z alpha-1 antitrypsin. Mol Ther 2023; 31:2651-2661. [PMID: 37394797 PMCID: PMC10492024 DOI: 10.1016/j.ymthe.2023.06.018] [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: 04/19/2023] [Revised: 06/06/2023] [Accepted: 06/28/2023] [Indexed: 07/04/2023] Open
Abstract
Mutant Z alpha-1 antitrypsin (ATZ) accumulates in globules in the liver and is the prototype of proteotoxic hepatic disease. Therapeutic strategies aiming at clearance of polymeric ATZ are needed. Transient receptor potential mucolipin-1 (TRPML1) is a lysosomal Ca2+ channel that maintains lysosomal homeostasis. In this study, we show that by increasing lysosomal exocytosis, TRPML1 gene transfer or small-molecule-mediated activation of TRPML1 reduces hepatic ATZ globules and fibrosis in PiZ transgenic mice that express the human ATZ. ATZ globule clearance induced by TRPML1 occurred without increase in autophagy or nuclear translocation of TFEB. Our results show that targeting TRPML1 and lysosomal exocytosis is a novel approach for treatment of the liver disease due to ATZ and potentially other diseases due to proteotoxic liver storage.
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Affiliation(s)
- Nunzia Pastore
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy; Department of Translational Medicine, Medical Genetics, University of Naples Federico II, Naples, Italy.
| | | | - Rita Colonna
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Veronica Maffia
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Teresa Giuliano
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Bruno Maria Custode
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Bernadette Lombardi
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Elena Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Vincenzo Cacace
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Lucia De Stefano
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Edoardo Nusco
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Nicolina Cristina Sorrentino
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy; Department of Clinical Medicine and Surgery, University of Naples Federico II, Naples, Italy
| | - Pasquale Piccolo
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Nicola Brunetti-Pierri
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy; Department of Translational Medicine, Medical Genetics, University of Naples Federico II, Naples, Italy; Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine Program, University of Naples Federico II, Naples, Italy.
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20
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Zhang T, Li Y, Li C, Zang J, Gao E, Kroon JT, Qu X, Hussey PJ, Wang P. Exo84c interacts with VAP27 to regulate exocytotic compartment degradation and stigma senescence. Nat Commun 2023; 14:4888. [PMID: 37580356 PMCID: PMC10425460 DOI: 10.1038/s41467-023-40729-5] [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: 11/14/2022] [Accepted: 08/08/2023] [Indexed: 08/16/2023] Open
Abstract
In plants, exocyst subunit isoforms exhibit significant functional diversity in that they are involved in either protein secretion or autophagy, both of which are essential for plant development and survival. Although the molecular basis of autophagy is widely reported, its contribution to plant reproduction is not very clear. Here, we have identified Exo84c, a higher plant-specific Exo84 isoform, as having a unique function in modulating exocytotic compartment degradation during stigmatic tissue senescence. This process is achieved through its interaction with the ER localised VAP27 proteins, which regulate the turnover of Exo84c through the autophagy pathway. VAP27 recruits Exo84c onto the ER membrane as well as numerous ER-derived autophagosomes that are labelled with ATG8. These Exo84c/exocyst and VAP27 positive structures are accumulated in the vacuole for degradation, and this process is partially perturbed in the exo84c knock-out mutants. Interestingly, the exo84c mutant showed a prolonged effective pollination period with higher seed sets, possibly because of the delayed stigmatic senescence when Exo84c regulated autophagy is blocked. In conclusion, our studies reveal a link between the exocyst complex and the ER network in regulating the degradation of exocytosis vesicles, a process that is essential for normal papilla cell senescence and flower receptivity.
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Affiliation(s)
- Tong Zhang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Yifan Li
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Chengyang Li
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Jingze Zang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK
| | - Erlin Gao
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Johan T Kroon
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK
| | - Xiaolu Qu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Patrick J Hussey
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK
| | - Pengwei Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China.
- Hubei Hongshan Laboratory, Wuhan, 430070, China.
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21
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Rudinskiy M, Molinari M. ER-to-lysosome-associated degradation in a nutshell: mammalian, yeast, and plant ER-phagy as induced by misfolded proteins. FEBS Lett 2023; 597:1928-1945. [PMID: 37259628 DOI: 10.1002/1873-3468.14674] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 05/10/2023] [Accepted: 05/22/2023] [Indexed: 06/02/2023]
Abstract
Conserved catabolic pathways operate to remove aberrant polypeptides from the endoplasmic reticulum (ER), the major biosynthetic organelle of eukaryotic cells. The best known are the ER-associated degradation (ERAD) pathways that control the retrotranslocation of terminally misfolded proteins across the ER membrane for clearance by the cytoplasmic ubiquitin/proteasome system. In this review, we catalog folding-defective mammalian, yeast, and plant proteins that fail to engage ERAD machineries. We describe that they rather segregate in ER subdomains that eventually vesiculate. These ER-derived vesicles are captured by double membrane autophagosomes, engulfed by endolysosomes/vacuoles, or fused with degradative organelles to clear cells from their toxic cargo. These client-specific, mechanistically diverse ER-phagy pathways are grouped under the umbrella term of ER-to-lysosome-associated degradation for description in this essay.
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Affiliation(s)
- Mikhail Rudinskiy
- Università della Svizzera italiana, Lugano, Switzerland
- Institute for Research in Biomedicine, Bellinzona, Switzerland
- Department of Biology, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Maurizio Molinari
- Università della Svizzera italiana, Lugano, Switzerland
- Institute for Research in Biomedicine, Bellinzona, Switzerland
- School of Life Sciences, École Polytechnique Fédérale de Lausanne, Switzerland
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22
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Ruiz M, Lacaille F, Schrader C, Pons M, Socha P, Krag A, Sturm E, Bouchecareilh M, Strnad P. Pediatric and Adult Liver Disease in Alpha-1 Antitrypsin Deficiency. Semin Liver Dis 2023; 43:258-266. [PMID: 37402396 DOI: 10.1055/a-2122-7674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/06/2023]
Abstract
Alpha-1 antitrypsin deficiency (AATD) arises due to inherited variants in SERPINA1, the AAT gene that impairs the production or secretion of this hepatocellular protein and leads to a gain-of-function liver proteotoxicity. Homozygous Pi*Z pathogenic variant (Pi*ZZ genotype) is the leading cause of severe AATD. It manifests in 2 to 10% of carriers as neonatal cholestasis and 20 to 35% of adults as significant liver fibrosis. Both children and adults may develop an end-stage liver disease requiring liver transplantation. Heterozygous Pi*Z pathogenic variant (Pi*MZ genotype) constitutes an established disease modifier. Our review summarizes the natural history and management of subjects with both pediatric and adult AATD-associated liver disease. Current findings from a phase 2 clinical trial indicate that RNA silencing may constitute a viable therapeutic approach for adult AATD. In conclusion, AATD is an increasingly appreciated pediatric and adult liver disorder that is becoming an attractive target for modern pharmacologic strategies.
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Affiliation(s)
- Mathias Ruiz
- Hépatologie, Gastroentérologie et Nutrition Pédiatriques, Hôpital Femme Mère Enfant, Hospices civils de Lyon, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Lyon, France
| | - Florence Lacaille
- Service de Gastroentérologie-Nutrition Pédiatriques et Unité d'Hépatologie Pédiatrique Hôpital Universitaire Necker-Enfants Malades, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Paris, France
| | - Christina Schrader
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Aachen, Germany
| | - Monica Pons
- Liver Unit, Hospital Universitari Vall d'Hebron, Vall d'Hebron Research Institute (VHIR), Universitat Autonoma de Barcelona, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
| | - Piotr Socha
- The Children's Memorial Health Institute, Department of Gastroenterology, Hepatology, Nutritional Disorders and Pediatrics, Al. Dzieci Polskich, Warszawa, Poland
| | - Aleksander Krag
- Department of Gastroenterology and Hepatology, Odense University Hospital, Odense, Denmark
| | - Ekkehard Sturm
- Pediatric Gastroenterology and Hepatology, University Children's Hospital Tübingen, Member Center of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Tübingen, Germany
| | | | - Pavel Strnad
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, Health Care Provider of the European Reference Network on Rare Liver Disorders (ERN RARE LIVER), Aachen, Germany
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23
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Zhang Y, Zhang Y, Chen T, Lin Y, Gong J, Xu Q, Wang J, Li J, Meng Y, Li Y, Li X. Caveolin-1 depletion attenuates hepatic fibrosis via promoting SQSTM1-mediated PFKL degradation in HSCs. Free Radic Biol Med 2023; 204:95-107. [PMID: 37116593 DOI: 10.1016/j.freeradbiomed.2023.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/15/2023] [Accepted: 04/18/2023] [Indexed: 04/30/2023]
Abstract
The key glycolytic enzyme phosphofructokinase (PFK) is responsible for maintaining glycolytic stability and an important energy source for activating hepatic stellate cells (HSCs). However, its regulation in activated HSCs remains unclear. Caveolin-1 (Cav1), a major constituent of caveolae, has emerged as a key target for triggering glycolysis. However, the relationship between Cav1 and glycolysis during HSC activation is not well established. In this study, Cav1 was upregulated in mouse and human fibrotic liver tissues. We concluded that HSC-specific Cav1 knockdown markedly alleviates liver injury and fibrosis. Mechanistically, Cav1 was elevated during primary mouse HSC activation, competing with SQSTM1 for the regulatory subunit of PFK liver type and inhibiting the SQSTM1-mediated autophagy-independent lysosomal degradation pathway to sustain HSC activation. We also identified the heptapeptide alamandine as a promising therapeutic agent that downregulates Cav1 protein levels via proteasomal degradation and may impair glycolysis. Our study provides evidence of the crucial role and mechanism of Cav1 in the glucose metabolic network in HSCs and highlights Cav1 as a critical therapeutic target for the treatment of liver fibrosis.
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Affiliation(s)
- Yan Zhang
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China
| | - Yijie Zhang
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China
| | - Tingting Chen
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China
| | - Ying Lin
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China
| | - Jiacheng Gong
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China
| | - Qihan Xu
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China
| | - Jun Wang
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China
| | - Jierui Li
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China
| | - Ying Meng
- Department of Respiratory Diseases, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China.
| | - Yang Li
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China.
| | - Xu Li
- Department of Emergency Medicine, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, China.
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Alabdulaali B, Al-rashed F, Al-Onaizi M, Kandari A, Razafiarison J, Tonui D, Williams MR, Blériot C, Ahmad R, Alzaid F. Macrophages and the development and progression of non-alcoholic fatty liver disease. Front Immunol 2023; 14:1195699. [PMID: 37377968 PMCID: PMC10291618 DOI: 10.3389/fimmu.2023.1195699] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023] Open
Abstract
The liver is the site of first pass metabolism, detoxifying and metabolizing blood arriving from the hepatic portal vein and hepatic artery. It is made up of multiple cell types, including macrophages. These are either bona fide tissue-resident Kupffer cells (KC) of embryonic origin, or differentiated from circulating monocytes. KCs are the primary immune cells populating the liver under steady state. Liver macrophages interact with hepatocytes, hepatic stellate cells, and liver sinusoidal endothelial cells to maintain homeostasis, however they are also key contributors to disease progression. Generally tolerogenic, they physiologically phagocytose foreign particles and debris from portal circulation and participate in red blood cell clearance. However as immune cells, they retain the capacity to raise an alarm to recruit other immune cells. Their aberrant function leads to the development of non-alcoholic fatty liver disease (NAFLD). NAFLD refers to a spectrum of conditions ranging from benign steatosis of the liver to steatohepatitis and cirrhosis. In NAFLD, the multiple hit hypothesis proposes that simultaneous influences from the gut and adipose tissue (AT) generate hepatic fat deposition and that inflammation plays a key role in disease progression. KCs initiate the inflammatory response as resident immune effectors, they signal to neighbouring cells and recruit monocytes that differentiated into recruited macrophages in situ. Recruited macrophages are central to amplifying the inflammatory response and causing progression of NAFLD to its fibro-inflammatory stages. Given their phagocytic capacity and their being instrumental in maintaining tissue homeostasis, KCs and recruited macrophages are fast-becoming target cell types for therapeutic intervention. We review the literature in the field on the roles of these cells in the development and progression of NAFLD, the characteristics of patients with NAFLD, animal models used in research, as well as the emerging questions. These include the gut-liver-brain axis, which when disrupted can contribute to decline in function, and a discussion on therapeutic strategies that act on the macrophage-inflammatory axis.
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Affiliation(s)
- Bader Alabdulaali
- Dasman Diabetes Institute, Kuwait City, Kuwait
- Ministry of Health, Kuwait City, Kuwait
| | | | - Mohammed Al-Onaizi
- Dasman Diabetes Institute, Kuwait City, Kuwait
- Department of Anatomy, Faculty of Medicine, Kuwait University, Kuwait City, Kuwait
| | - Anwar Kandari
- Dasman Diabetes Institute, Kuwait City, Kuwait
- Ministry of Health, Kuwait City, Kuwait
| | - Joanna Razafiarison
- INSERM UMR-S1151, CNRS UMR-S8253, Université Paris Cité, Institut Necker Enfants Malades, Paris, France
| | - Dorothy Tonui
- INSERM UMR-S1151, CNRS UMR-S8253, Université Paris Cité, Institut Necker Enfants Malades, Paris, France
| | | | - Camille Blériot
- INSERM UMR-S1151, CNRS UMR-S8253, Université Paris Cité, Institut Necker Enfants Malades, Paris, France
- Inserm U1015, Gustave Roussy, Villejuif, France
| | | | - Fawaz Alzaid
- Dasman Diabetes Institute, Kuwait City, Kuwait
- INSERM UMR-S1151, CNRS UMR-S8253, Université Paris Cité, Institut Necker Enfants Malades, Paris, France
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25
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Chen X, Qin W, Wang L, Jin Y, Tu J, Yuan X. Autophagy gene Atg7 regulates the development of radiation-induced skin injury and fibrosis of skin. Skin Res Technol 2023; 29:e13337. [PMID: 37357660 PMCID: PMC10230157 DOI: 10.1111/srt.13337] [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: 01/09/2023] [Accepted: 04/17/2023] [Indexed: 06/27/2023]
Abstract
BACKGROUND Radiation-induced skin injury, which may progress to fibrosis, is a severe side effect of radiotherapy in patients with cancer. However, currently, there is a lack of preventive or curative treatments for this injury. Meanwhile, the mechanisms underlying this injury remain poorly understood. Here, we elucidated whether autophagy is essential for the development of radiation-induced skin injury and the potential molecular pathways and mechanisms involved. METHODS AND RESULTS We used the myofibroblast-specific Atg7 knockout (namely, conditional Atg7 knockout) mice irradiated with a single electron beam irradiation dose of 30 Gy. Vaseline-based 0.2% rapamycin ointment was topically applied once daily from the day of irradiation for 30 days. On day 30 post irradiation, skin tissues were harvested for further analysis. In vitro, human foreskin fibroblast cells were treated with rapamycin (100 nM) for 24 h and pretreated with 3-MA (5 mM) for 12 h. Macroscopic skin manifestations, histological changes, and fibrosis markers at the mRNA and protein expression levels were measured. Post irradiation, the myofibroblast-specific autophagy-deficient (Atg7Flox/Flox Cre+ ) mice had increased fibrosis marker (COL1A1, CTGF, TGF-β1, and α-SMA) levels in the irradiated area and had more severe macroscopic skin manifestations than the control group (Atg7Flox/Flox Cre- ) mice. Treatment with an autophagy agonist rapamycin attenuated macroscopic skin injury scores and skin fibrosis marker levels with decreased epidermal thickness and dermal collagen deposition in Atg7Flox/Flox Cre+ mice compared with the vehicle control. Moreover, in vitro experiment results were consistent with the in vivo results. Together with studies at the molecular level, we found that these changes involved the Akt/mTOR pathway. In addition, this phenomenon might also relate to Nrf2-autophagy signaling pathway under oxidative stress conditions. CONCLUSION In conclusion, Atg7 and autophagy-related mechanisms confer radioprotection, and reactivation of the autophagy process can be a novel therapeutic strategy to reduce and prevent the occurrence of radiodermatitis, particularly skin fibrosis, in patients with cancer.
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Affiliation(s)
- Xinyi Chen
- Department of OncologyTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiChina
| | - Wan Qin
- Department of OncologyTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiChina
| | - Lu Wang
- Department of OncologyTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiChina
| | - Yu Jin
- Department of OncologyTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiChina
| | - Jingyao Tu
- Department of OncologyTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiChina
| | - Xianglin Yuan
- Department of OncologyTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiChina
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26
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Gilgenkrantz H, Paradis V, Lotersztajn S. Cell metabolism-based therapy for liver fibrosis, repair, and hepatocellular carcinoma. Hepatology 2023:01515467-990000000-00454. [PMID: 37212145 DOI: 10.1097/hep.0000000000000479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 04/21/2023] [Indexed: 05/23/2023]
Abstract
Progression of chronic liver injury to fibrosis, abnormal liver regeneration, and HCC is driven by a dysregulated dialog between epithelial cells and their microenvironment, in particular immune, fibroblasts, and endothelial cells. There is currently no antifibrogenic therapy, and drug treatment of HCC is limited to tyrosine kinase inhibitors and immunotherapy targeting the tumor microenvironment. Metabolic reprogramming of epithelial and nonparenchymal cells is critical at each stage of disease progression, suggesting that targeting specific metabolic pathways could constitute an interesting therapeutic approach. In this review, we discuss how modulating intrinsic metabolism of key effector liver cells might disrupt the pathogenic sequence from chronic liver injury to fibrosis/cirrhosis, regeneration, and HCC.
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Affiliation(s)
- Hélène Gilgenkrantz
- Paris-Cité University, INSERM, Center for Research on Inflammation, Paris, France
| | - Valérie Paradis
- Paris-Cité University, INSERM, Center for Research on Inflammation, Paris, France
- Pathology Department, Beaujon Hospital APHP, Paris-Cité University, Clichy, France
| | - Sophie Lotersztajn
- Paris-Cité University, INSERM, Center for Research on Inflammation, Paris, France
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27
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Hua QQ, Lin XJ, Xiang SP, Jiang LY, Cai JH, Sun JM, Tan F, Mou YN. Two small-molecule inhibitors of Toxoplasma gondii proliferation in vitro. Front Cell Infect Microbiol 2023; 13:1145824. [PMID: 37077525 PMCID: PMC10106592 DOI: 10.3389/fcimb.2023.1145824] [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: 01/16/2023] [Accepted: 03/20/2023] [Indexed: 04/05/2023] Open
Abstract
Background Toxoplasmosis caused by Toxoplasma gondii is a globally distributed zoonosis. Most infections appear asymptomatic in immunocompetent individuals, but toxoplasmosis can be fatal in fetuses and immunocompromised adults. There is an urgent need to research and develop effective and low-toxicity anti-T. gondii drugs because of some defects in current clinical anti-T. gondii drugs, such as limited efficacy, serious side effects and drug resistance. Methods In this study, 152 autophagy related compounds were evaluated as anti-T. gondii drugs. The activity of β-galactosidase assay based on luminescence was used to determine the inhibitory effect on parasite growth. At the same time, MTS assay was used to further detect the effects of compounds with over 60% inhibition rate on host cell viability. The invasion, intracellular proliferation, egress and gliding abilities of T. gondii were tested to assess the inhibitory effect of the chosen drugs on the distinct steps of the T. gondii lysis cycle. Results The results showed that a total of 38 compounds inhibited parasite growth by more than 60%. After excluding the compounds affecting host cell activity, CGI-1746 and JH-II-127 were considered for drug reuse and further characterized. Both CGI-1746 and JH-II-127 inhibited tachyzoite growth by 60%, with IC50 values of 14.58 ± 1.52 and 5.88 ± 0.23 μM, respectively. TD50 values were 154.20 ± 20.15 and 76.39 ± 14.32 μM, respectively. Further research found that these two compounds significantly inhibited the intracellular proliferation of tachyzoites. Summarize the results, we demonstrated that CGI-1746 inhibited the invasion, egress and especially the gliding abilities of parasites, which is essential for the successful invasion of host cells, while JH-II-127 did not affect the invasion and gliding ability, but seriously damaged the morphology of mitochondria which may be related to the damage of mitochondrial electron transport chain. Discussion Taken together, these findings suggest that both CGI-1746 and JH-II-127 could be potentially repurposed as anti-T. gondii drugs, lays the groundwork for future therapeutic strategies.
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Affiliation(s)
- Qian-qian Hua
- Department of Clinical Laboratory, Affiliated Dongyang Hospital of Wenzhou Medical University, Dongyang, Zhejiang, China
| | - Xue-jing Lin
- Department of Parasitology, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Shi-peng Xiang
- Department of Parasitology, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Li-ya Jiang
- Department of Clinical Laboratory, Affiliated Dongyang Hospital of Wenzhou Medical University, Dongyang, Zhejiang, China
| | - Jin-hao Cai
- Department of Clinical Laboratory, Affiliated Dongyang Hospital of Wenzhou Medical University, Dongyang, Zhejiang, China
| | - Jian-min Sun
- Department of Clinical Laboratory, Affiliated Dongyang Hospital of Wenzhou Medical University, Dongyang, Zhejiang, China
| | - Feng Tan
- Department of Parasitology, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ya-ni Mou
- Department of Parasitology, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
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28
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McElvaney OF, Fraughen DD, McElvaney OJ, Carroll TP, McElvaney NG. Alpha-1 antitrypsin deficiency: current therapy and emerging targets. Expert Rev Respir Med 2023; 17:191-202. [PMID: 36896570 DOI: 10.1080/17476348.2023.2174973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
INTRODUCTION Alpha1 antitrypsin deficiency (AATD), a common hereditary disorder affecting mainly lungs, liver and skin has been the focus of some of the most exciting therapeutic approaches in medicine in the past 5 years. In this review, we discuss the therapies presently available for the different manifestations of AATD and new therapies in the pipeline. AREAS COVERED We review therapeutic options for the individual lung, liver and skin manifestations of AATD along with approaches which aim to treat all three. Along with this renewed interest in treating AATD come challenges. How is AAT best delivered to the lung? What is the desired level of AAT in the circulation and lungs which therapeutics should aim to provide? Will treating the liver disease increase the potential for lung disease? Are there treatments to target the underlying genetic defect with the potential to prevent all aspects of AATDrelated disease? EXPERT OPINION With a relatively small population able to participate in clinical studies, increased awareness and diagnosis of AATD is urgently needed. Better, more sensitive clinical parameters will assist in the generation of acceptable and robust evidence of therapeutic effect for current and emerging treatments.
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Affiliation(s)
- Oisín F McElvaney
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland
| | - Daniel D Fraughen
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland
| | - Oliver J McElvaney
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland
| | - Tomás P Carroll
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland.,Alpha-1 Foundation Ireland, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Noel G McElvaney
- Irish Centre for Genetic Lung Disease, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Medicine, Beaumont Hospital, Dublin, Ireland
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29
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Li Y, Guha C, Asp P, Wang X, Tchaikovskya TL, Kim K, Mendel M, Cost GJ, Perlmutter DH, Roy-Chowdhury N, Fox IJ, Conway A, Roy-Chowdhury J. Resolution of hepatic fibrosis after ZFN-mediated gene editing in the PiZ mouse model of human α1-antitrypsin deficiency. Hepatol Commun 2023; 7:e0070. [PMID: 36848094 PMCID: PMC9974076 DOI: 10.1097/hc9.0000000000000070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 12/21/2022] [Indexed: 03/01/2023] Open
Abstract
BACKGROUND α1-antitrypsin deficiency is most commonly caused by a mutation in exon-7 of SERPINA1 (SA1-ATZ), resulting in hepatocellular accumulation of a misfolded variant (ATZ). Human SA1-ATZ-transgenic (PiZ) mice exhibit hepatocellular ATZ accumulation and liver fibrosis. We hypothesized that disrupting the SA1-ATZ transgene in PiZ mice by in vivo genome editing would confer a proliferative advantage to the genome-edited hepatocytes, enabling them to repopulate the liver. METHODS To create a targeted DNA break in exon-7 of the SA1-ATZ transgene, we generated 2 recombinant adeno-associated viruses (rAAV) expressing a zinc-finger nuclease pair (rAAV-ZFN), and another rAAV for gene correction by targeted insertion (rAAV-TI). PiZ mice were injected i.v. with rAAV-TI alone or the rAAV-ZFNs at a low (7.5×1010vg/mouse, LD) or a high dose (1.5×1011vg/mouse, HD), with or without rAAV-TI. Two weeks and 6 months after treatment, livers were harvested for molecular, histological, and biochemical analyses. RESULTS Two weeks after treatment, deep sequencing of the hepatic SA1-ATZ transgene pool showed 6%±3% or 15%±4% nonhomologous end joining in mice receiving LD or HD rAAV-ZFN, respectively, which increased to 36%±12% and 36%±12%, respectively, 6 months after treatment. Two weeks postinjection of rAAV-TI with LD or HD of rAAV-ZFN, repair by targeted insertion occurred in 0.10%±0.09% and 0.25%±0.14% of SA1-ATZ transgenes, respectively, which increased to 5.2%±5.0% and 33%±13%, respectively, 6 months after treatment. Six months after rAAV-ZFN administration, there was a marked clearance of ATZ globules from hepatocytes, and resolution of liver fibrosis, along with reduction of hepatic TAZ/WWTR1, hedgehog ligands, Gli2, a TIMP, and collagen content. CONCLUSIONS ZFN-mediated SA1-ATZ transgene disruption provides a proliferative advantage to ATZ-depleted hepatocytes, enabling them to repopulate the liver and reverse hepatic fibrosis.
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Affiliation(s)
- Yanfeng Li
- Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
| | - Chandan Guha
- Department of Radiation Oncology, Albert Einstein College of Medicine, New York, New York, USA
- Department of Pathology, Albert Einstein College of Medicine, New York, New York, USA
- Marion Bessin Liver Research Center, Albert Einstein College of Medicine, New York, New York, USA
| | - Patrik Asp
- Department of Radiation Oncology, Albert Einstein College of Medicine, New York, New York, USA
- Marion Bessin Liver Research Center, Albert Einstein College of Medicine, New York, New York, USA
| | - Xia Wang
- Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
| | - Tatyana L. Tchaikovskya
- Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
- Marion Bessin Liver Research Center, Albert Einstein College of Medicine, New York, New York, USA
| | - Kenneth Kim
- Sangamo Therapeutics, Richmond, California, USA
| | | | | | - David H. Perlmutter
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Namita Roy-Chowdhury
- Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
- Marion Bessin Liver Research Center, Albert Einstein College of Medicine, New York, New York, USA
- Department of Genetics, Albert Einstein College of Medicine, New York, New York, USA
| | - Ira J. Fox
- Department of Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | | | - Jayanta Roy-Chowdhury
- Department of Medicine, Albert Einstein College of Medicine, New York, New York, USA
- Marion Bessin Liver Research Center, Albert Einstein College of Medicine, New York, New York, USA
- Department of Genetics, Albert Einstein College of Medicine, New York, New York, USA
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30
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Ahmadi-Dehlaghi F, Mohammadi P, Valipour E, Pournaghi P, Kiani S, Mansouri K. Autophagy: A challengeable paradox in cancer treatment. Cancer Med 2023. [PMID: 36760166 DOI: 10.1002/cam4.5577] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 11/14/2022] [Accepted: 12/21/2022] [Indexed: 02/11/2023] Open
Abstract
OBJECTIVE Autophagy is an intracellular degradation pathway conserved in all eukaryotes from yeast to humans. This process plays a quality-control role by destroying harmful cellular components under normal conditions, maintaining cell survival, and establishing cellular adaptation under stressful conditions. Hence, there are various studies indicating dysfunctional autophagy as a factor involved in the development and progression of various human diseases, including cancer. In addition, the importance of autophagy in the development of cancer has been highlighted by paradoxical roles, as a cytoprotective and cytotoxic mechanism. Despite extensive research in the field of cancer, there are many questions and challenges about the roles and effects suggested for autophagy in cancer treatment. The aim of this study was to provide an overview of the paradoxical roles of autophagy in different tumors and related cancer treatment options. METHODS In this study, to find articles, a search was made in PubMed and Google scholar databases with the keywords Autophagy, Autophagy in Cancer Management, and Drug Design. RESULTS According to the investigation, some studies suggest that several advanced cancers are dependent on autophagy for cell survival, so when cancer cells are exposed to therapy, autophagy is induced and suppresses the anti-cancer effects of therapeutic agents and also results in cell resistance. However, enhanced autophagy from using anti-cancer drugs causes autophagy-mediated cell death in several cancers. Because autophagy also plays roles in both tumor suppression and promotion further research is needed to determine the precise mechanism of this process in cancer treatment. CONCLUSION We concluded in this article, autophagy manipulation may either promote or hinder the growth and development of cancer according to the origin of the cancer cells, the type of cancer, and the behavior of the cancer cells exposed to treatment. Thus, before starting treatment it is necessary to determine the basal levels of autophagy in various cancers.
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Affiliation(s)
- Farnaz Ahmadi-Dehlaghi
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran.,Department of Biology, Payame Noor University, Tehran, Iran
| | - Parisa Mohammadi
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran.,Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Science, Tehran, Iran
| | - Elahe Valipour
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Sarah Kiani
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Kamran Mansouri
- Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
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31
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Fung C, Wilding B, Schittenhelm RB, Bryson-Richardson RJ, Bird PI. Expression of the Z Variant of α1-Antitrypsin Suppresses Hepatic Cholesterol Biosynthesis in Transgenic Zebrafish. Int J Mol Sci 2023; 24:ijms24032475. [PMID: 36768797 PMCID: PMC9917206 DOI: 10.3390/ijms24032475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 01/20/2023] [Accepted: 01/21/2023] [Indexed: 01/31/2023] Open
Abstract
Individuals homozygous for the Pi*Z allele of SERPINA1 (ZAAT) are susceptible to lung disease due to insufficient α1-antitrypsin secretion into the circulation and may develop liver disease due to compromised protein folding that leads to inclusion body formation in the endoplasmic reticulum (ER) of hepatocytes. Transgenic zebrafish expressing human ZAAT show no signs of hepatic accumulation despite displaying serum insufficiency, suggesting the defect in ZAAT secretion occurs independently of its tendency to form inclusion bodies. In this study, proteomic, transcriptomic, and biochemical analysis provided evidence of suppressed Srebp2-mediated cholesterol biosynthesis in the liver of ZAAT-expressing zebrafish. To investigate the basis for this perturbation, CRISPR/Cas9 gene editing was used to manipulate ER protein quality control factors. Mutation of erlec1 resulted in a further suppression in the cholesterol biosynthesis pathway, confirming a role for this ER lectin in targeting misfolded ZAAT for ER-associated degradation (ERAD). Mutation of the two ER mannosidase homologs enhanced ZAAT secretion without inducing hepatic accumulation. These insights into hepatic ZAAT processing suggest potential therapeutic targets to improve secretion and alleviate serum insufficiency in this form of the α1-antitrypsin disease.
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Affiliation(s)
- Connie Fung
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne 3800, Australia
- Correspondence: (C.F.); (P.I.B.)
| | - Brendan Wilding
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne 3800, Australia
| | - Ralf B. Schittenhelm
- Monash Proteomics and Metabolomics Facility, Monash University, Melbourne 3800, Australia
| | | | - Phillip I. Bird
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne 3800, Australia
- Correspondence: (C.F.); (P.I.B.)
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32
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Sun S, Wang C, Zhao P, Kline GM, Grandjean JMD, Jiang X, Labaudiniere R, Wiseman RL, Kelly JW, Balch WE. Capturing the conversion of the pathogenic alpha-1-antitrypsin fold by ATF6 enhanced proteostasis. Cell Chem Biol 2023; 30:22-42.e5. [PMID: 36630963 PMCID: PMC9930901 DOI: 10.1016/j.chembiol.2022.12.004] [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: 08/30/2022] [Revised: 11/07/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023]
Abstract
Genetic variation in alpha-1 antitrypsin (AAT) causes AAT deficiency (AATD) through liver aggregation-associated gain-of-toxic pathology and/or insufficient AAT activity in the lung manifesting as chronic obstructive pulmonary disease (COPD). Here, we utilize 71 AATD-associated variants as input through Gaussian process (GP)-based machine learning to study the correction of AAT folding and function at a residue-by-residue level by pharmacological activation of the ATF6 arm of the unfolded protein response (UPR). We show that ATF6 activators increase AAT neutrophil elastase (NE) inhibitory activity, while reducing polymer accumulation for the majority of AATD variants, including the prominent Z variant. GP-based profiling of the residue-by-residue response to ATF6 activators captures an unexpected role of the "gate" area in managing AAT-specific activity. Our work establishes a new spatial covariant (SCV) understanding of the convertible state of the protein fold in response to genetic perturbation and active environmental management by proteostasis enhancement for precision medicine.
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Affiliation(s)
- Shuhong Sun
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Chao Wang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Pei Zhao
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Gabe M Kline
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | | | - Xin Jiang
- Protego Biopharma, 10945 Vista Sorrento Parkway, San Diego, CA, USA
| | | | - R Luke Wiseman
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Jeffery W Kelly
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - William E Balch
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA.
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33
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Shrestha N, Torres M, Zhang J, Lu Y, Haataja L, Reinert RB, Knupp J, Chen YJ, Parlakgul G, Arruda AP, Tsai B, Arvan P, Qi L. Integration of ER protein quality control mechanisms defines β cell function and ER architecture. J Clin Invest 2023; 133:e163584. [PMID: 36346671 PMCID: PMC9797341 DOI: 10.1172/jci163584] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
Three principal ER quality-control mechanisms, namely, the unfolded protein response, ER-associated degradation (ERAD), and ER-phagy are each important for the maintenance of ER homeostasis, yet how they are integrated to regulate ER homeostasis and organellar architecture in vivo is largely unclear. Here we report intricate crosstalk among the 3 pathways, centered around the SEL1L-HRD1 protein complex of ERAD, in the regulation of organellar organization in β cells. SEL1L-HRD1 ERAD deficiency in β cells triggers activation of autophagy, at least in part, via IRE1α (an endogenous ERAD substrate). In the absence of functional SEL1L-HRD1 ERAD, proinsulin is retained in the ER as high molecular weight conformers, which are subsequently cleared via ER-phagy. A combined loss of both SEL1L and autophagy in β cells leads to diabetes in mice shortly after weaning, with premature death by approximately 11 weeks of age, associated with marked ER retention of proinsulin and β cell loss. Using focused ion beam scanning electron microscopy powered by deep-learning automated image segmentation and 3D reconstruction, our data demonstrate a profound organellar restructuring with a massive expansion of ER volume and network in β cells lacking both SEL1L and autophagy. These data reveal at an unprecedented detail the intimate crosstalk among the 3 ER quality-control mechanisms in the dynamic regulation of organellar architecture and β cell function.
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Affiliation(s)
- Neha Shrestha
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Mauricio Torres
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jason Zhang
- Department of Molecular, Cellular, and Developmental Biology, School of Literature, Science, and the Arts, University of Michigan, Ann Arbor, Michigan, USA
| | - You Lu
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Leena Haataja
- Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Rachel B. Reinert
- Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jeffrey Knupp
- Department of Cell and Development Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Yu-Jie Chen
- Department of Cell and Development Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Gunes Parlakgul
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Ana Paula Arruda
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
- Chan Zuckerberg Biohub, San Francisco, California, USA
| | - Billy Tsai
- Department of Cell and Development Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Peter Arvan
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ling Qi
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
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Chen G, Wei T, Ju F, Li H. Protein quality control and aggregation in the endoplasmic reticulum: From basic to bedside. Front Cell Dev Biol 2023; 11:1156152. [PMID: 37152279 PMCID: PMC10154544 DOI: 10.3389/fcell.2023.1156152] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 04/10/2023] [Indexed: 05/09/2023] Open
Abstract
Endoplasmic reticulum (ER) is the largest membrane-bound compartment in all cells and functions as a key regulator in protein biosynthesis, lipid metabolism, and calcium balance. Mammalian endoplasmic reticulum has evolved with an orchestrated protein quality control system to handle defective proteins and ensure endoplasmic reticulum homeostasis. Nevertheless, the accumulation and aggregation of misfolded proteins in the endoplasmic reticulum may occur during pathological conditions. The inability of endoplasmic reticulum quality control system to clear faulty proteins and aggregates from the endoplasmic reticulum results in the development of many human disorders. The efforts to comprehensively understand endoplasmic reticulum quality control network and protein aggregation will benefit the diagnostics and therapeutics of endoplasmic reticulum storage diseases. Herein, we overview recent advances in mammalian endoplasmic reticulum protein quality control system, describe protein phase transition model, and summarize the approaches to monitor protein aggregation. Moreover, we discuss the therapeutic applications of enhancing endoplasmic reticulum protein quality control pathways in endoplasmic reticulum storage diseases.
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Affiliation(s)
- Guofang Chen
- Shanghai Key Laboratory of Maternal Fetal Medicine, Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China
| | - Tingyi Wei
- Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Institute of Precision Medicine, Shanghai, China
| | - Furong Ju
- Ming Wai Lau Centre for Reparative Medicine, Karolinska Institutet, Sha Tin, Hong kong SAR, China
| | - Haisen Li
- School of Life Sciences, Fudan University, Shanghai, China
- AoBio Medical, Shanghai, China
- *Correspondence: Haisen Li,
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35
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Melnyk A, Lang S, Sicking M, Zimmermann R, Jung M. Co-chaperones of the Human Endoplasmic Reticulum: An Update. Subcell Biochem 2023; 101:247-291. [PMID: 36520310 DOI: 10.1007/978-3-031-14740-1_9] [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] [Indexed: 06/17/2023]
Abstract
In mammalian cells, the rough endoplasmic reticulum (ER) plays central roles in the biogenesis of extracellular plus organellar proteins and in various signal transduction pathways. For these reasons, the ER comprises molecular chaperones, which are involved in import, folding, assembly, export, plus degradation of polypeptides, and signal transduction components, such as calcium channels, calcium pumps, and UPR transducers plus adenine nucleotide carriers/exchangers in the ER membrane. The calcium- and ATP-dependent ER lumenal Hsp70, termed immunoglobulin heavy-chain-binding protein or BiP, is the central player in all these activities and involves up to nine different Hsp40-type co-chaperones, i.e., ER membrane integrated as well as ER lumenal J-domain proteins, termed ERj or ERdj proteins, two nucleotide exchange factors or NEFs (Grp170 and Sil1), and NEF-antagonists, such as MANF. Here we summarize the current knowledge on the ER-resident BiP/ERj chaperone network and focus on the interaction of BiP with the polypeptide-conducting and calcium-permeable Sec61 channel of the ER membrane as an example for BiP action and how its functional cycle is linked to ER protein import and various calcium-dependent signal transduction pathways.
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Affiliation(s)
- Armin Melnyk
- Medical Biochemistry & Molecular Biology, Saarland University, Homburg, Germany
| | - Sven Lang
- Medical Biochemistry & Molecular Biology, Saarland University, Homburg, Germany
| | - Mark Sicking
- Medical Biochemistry & Molecular Biology, Saarland University, Homburg, Germany
| | - Richard Zimmermann
- Medical Biochemistry & Molecular Biology, Saarland University, Homburg, Germany.
| | - Martin Jung
- Medical Biochemistry & Molecular Biology, Saarland University, Homburg, Germany
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36
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Kaserman JE, Werder RB, Wang F, Matte T, Higgins MI, Dodge M, Lindstrom-Vautrin J, Bawa P, Hinds A, Bullitt E, Caballero IS, Shi X, Gerszten RE, Brunetti-Pierri N, Liesa M, Villacorta-Martin C, Hollenberg AN, Kotton DN, Wilson AA. Human iPSC-hepatocyte modeling of alpha-1 antitrypsin heterozygosity reveals metabolic dysregulation and cellular heterogeneity. Cell Rep 2022; 41:111775. [PMID: 36476855 PMCID: PMC9780780 DOI: 10.1016/j.celrep.2022.111775] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/28/2022] [Accepted: 11/14/2022] [Indexed: 12/12/2022] Open
Abstract
Individuals homozygous for the "Z" mutation in alpha-1 antitrypsin deficiency are known to be at increased risk for liver disease. It has also become clear that some degree of risk is similarly conferred by the heterozygous state. A lack of model systems that recapitulate heterozygosity in human hepatocytes has limited the ability to study the impact of a single Z alpha-1 antitrypsin (ZAAT) allele on hepatocyte biology. Here, we describe the derivation of syngeneic induced pluripotent stem cells (iPSCs) engineered to determine the effects of ZAAT heterozygosity in iPSC-hepatocytes (iHeps). We find that heterozygous MZ iHeps exhibit an intermediate disease phenotype and share with ZZ iHeps alterations in AAT protein processing and downstream perturbations including altered endoplasmic reticulum (ER) and mitochondrial morphology, reduced mitochondrial respiration, and branch-specific activation of the unfolded protein response in cell subpopulations. Our model of MZ heterozygosity thus provides evidence that a single Z allele is sufficient to disrupt hepatocyte homeostatic function.
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Affiliation(s)
- Joseph E. Kaserman
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA,The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Rhiannon B. Werder
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Feiya Wang
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Taylor Matte
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Michelle I. Higgins
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Mark Dodge
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Jonathan Lindstrom-Vautrin
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Pushpinder Bawa
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Anne Hinds
- The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Esther Bullitt
- Department of Physiology and Biophysics, Boston University, Boston, MA 02118, USA
| | - Ignacio S. Caballero
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Xu Shi
- Division of Cardiovascular Medicine, Beth Israel Deaconess Hospital, Boston, MA 02118, USA
| | - Robert E. Gerszten
- Division of Cardiovascular Medicine, Beth Israel Deaconess Hospital, Boston, MA 02118, USA
| | - Nicola Brunetti-Pierri
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Naples, Italy,Department of Translational Medicine, Federico II University, 80131 Naples, Italy
| | - Marc Liesa
- Departments of Medicine, Endocrinology, and Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA,Institut de Biologia Molecular de Barcelona (IBMB-CSIC), 08028 Barcelona, Catalonia, Spain
| | - Carlos Villacorta-Martin
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA
| | - Anthony N. Hollenberg
- Joan and Sanford I. Weill Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Weill Cornell Medicine, 1300 York Avenue, New York, NY 10065, USA
| | - Darrell N. Kotton
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA,The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Andrew A. Wilson
- Center for Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, MA 02118, USA,The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA,Lead contact,Correspondence:
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Bettag J, Po L, Cunningham C, Tallam R, Kurashima K, Nagarapu A, Hutchinson C, Morfin S, Nazzal M, Lin CJ, Mathur A, Aurora R, Jain AK. Novel Therapeutic Approaches for Mitigating Complications in Short Bowel Syndrome. Nutrients 2022; 14:4660. [PMID: 36364922 PMCID: PMC9658734 DOI: 10.3390/nu14214660] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
Short bowel syndrome (SBS) is a particularly serious condition in which the small intestine does not absorb sufficient nutrients for biological needs, resulting in severe illness and potentially death if not treated. Given the important role of the gut in many signaling cascades throughout the body, SBS results in disruption of many pathways and imbalances in various hormones. Due to the inability to meet sufficient nutritional needs, an intravenous form of nutrition, total parental nutrition (TPN), is administered. However, TPN presents difficulties such as severe liver injury and altered signaling secondary to the continued lack of luminal contents. This manuscript aims to summarize relevant studies into the systemic effects of TPN on systems such as the gut-brain, gut-lung, and gut-liver axis, as well as present novel therapeutics currently under use or investigation as mitigation strategies for TPN induced injury.
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Affiliation(s)
- Jeffery Bettag
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Loren Po
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Cassius Cunningham
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Rahul Tallam
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Kento Kurashima
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Aakash Nagarapu
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Chelsea Hutchinson
- Department of Surgery, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Sylvia Morfin
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Mustafa Nazzal
- Department of Surgery, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Chien-Jung Lin
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Amit Mathur
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Rajeev Aurora
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
| | - Ajay K. Jain
- Department of Pediatrics, Saint Louis University School of Medicine, Saint Louis, MO 63103, USA
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Cherubini A, Zito E. ER stress as a trigger of UPR and ER-phagy in cancer growth and spread. Front Oncol 2022; 12:997235. [PMID: 36408145 PMCID: PMC9667062 DOI: 10.3389/fonc.2022.997235] [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: 07/18/2022] [Accepted: 10/12/2022] [Indexed: 01/25/2023] Open
Abstract
Tumors can survive environmental and metabolic stress by triggering homeostatic responses that re-establish the pre-stress status and permit them to grow and thrive. The endoplasmic reticulum (ER) is the organelle where proteins undergo post-translational modifications and are folded and exported to the secretory pathway. Its environment and activity are therefore fundamental for proteostasis, i.e., the plethora of mechanisms controlling protein formation, folding, degradation, and secretion, needed to assure protein balance and cellular health. In different tumor-related conditions, such as after the activation of oncogenes or under hypoxia and nutrient deprivation, the ER experiences stress, triggered by a high load of proteins to be folded compared to the limited folding capacity of the organelle. As a consequence, three ER membrane sensors and the related unfolded protein response (UPR) are activated. The UPR comprises a complex interconnection between signal transduction pathways that promote a homeostatic response that acts by increasing the amount of protein chaperones and of proteins involved in ER-associated protein degradation (ERAD) on one hand and attenuating protein translation on the other. ER-phagy, literally "eating" the ER, is part of another homeostatic response consisting of the clearance of non-functional ER portions including misfolded proteins. This response is also activated by a set of dedicated ER-phagy receptors after ER stimuli, which overlap the stimuli generating ER stress. Thus, the UPR and ER-phagy are two closely related homeostatic mechanisms that cooperate in re-establishing ER homeostasis. However, while the role of the UPR in favoring cancer growth and thriving by promoting angiogenesis, metastasis, chemotherapy resistance, and epithelial-to-mesenchymal transition is consolidated, that of ER-phagy is still in its infancy. This essay provides an overview of emerging concepts on ER stress, the UPR, and ER-phagy and their crosstalk in tumorigenesis. We also critically review new findings on their pharmacological targeting in cancer.
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Affiliation(s)
- Alessandro Cherubini
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy,Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Ester Zito
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy,Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy,*Correspondence: Ester Zito,
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Zhou X, Li X, Yi K, Liang C, Geng S, Zhu J, Xie C, Zhong C. Magnesium isoglycyrrhizinate ameliorates lipopolysaccharide-induced liver injury by upregulating autophagy and inhibiting inflammation via IL-22 expression. Bioorg Chem 2022; 128:106034. [DOI: 10.1016/j.bioorg.2022.106034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/01/2022] [Accepted: 07/14/2022] [Indexed: 12/15/2022]
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40
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Oh YM, Lee SW, Kim WK, Chen S, Church VA, Cates K, Li T, Zhang B, Dolle RE, Dahiya S, Pak SC, Silverman GA, Perlmutter DH, Yoo AS. Age-related Huntington's disease progression modeled in directly reprogrammed patient-derived striatal neurons highlights impaired autophagy. Nat Neurosci 2022; 25:1420-1433. [PMID: 36303071 PMCID: PMC10162007 DOI: 10.1038/s41593-022-01185-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 09/19/2022] [Indexed: 01/13/2023]
Abstract
Huntington's disease (HD) is an inherited neurodegenerative disorder with adult-onset clinical symptoms, but the mechanism by which aging drives the onset of neurodegeneration in patients with HD remains unclear. In this study we examined striatal medium spiny neurons (MSNs) directly reprogrammed from fibroblasts of patients with HD to model the age-dependent onset of pathology. We found that pronounced neuronal death occurred selectively in reprogrammed MSNs from symptomatic patients with HD (HD-MSNs) compared to MSNs derived from younger, pre-symptomatic patients (pre-HD-MSNs) and control MSNs from age-matched healthy individuals. We observed age-associated alterations in chromatin accessibility between HD-MSNs and pre-HD-MSNs and identified miR-29b-3p, whose age-associated upregulation promotes HD-MSN degeneration by impairing autophagic function through human-specific targeting of the STAT3 3' untranslated region. Reducing miR-29b-3p or chemically promoting autophagy increased the resilience of HD-MSNs against neurodegeneration. Our results demonstrate miRNA upregulation with aging in HD as a detrimental process driving MSN degeneration and potential approaches for enhancing autophagy and resilience of HD-MSNs.
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Affiliation(s)
- Young Mi Oh
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Seong Won Lee
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Woo Kyung Kim
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Shawei Chen
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Victoria A Church
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Kitra Cates
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Tiandao Li
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
- Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Bo Zhang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
- Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Roland E Dolle
- Department of Biochemistry, Washington University School of Medicine, St. Louis, MO, USA
| | - Sonika Dahiya
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Stephen C Pak
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Gary A Silverman
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - David H Perlmutter
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Andrew S Yoo
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
- Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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41
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Lu G, Wang Y, Shi Y, Zhang Z, Huang C, He W, Wang C, Shen HM. Autophagy in health and disease: From molecular mechanisms to therapeutic target. MedComm (Beijing) 2022; 3:e150. [PMID: 35845350 PMCID: PMC9271889 DOI: 10.1002/mco2.150] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/01/2022] [Accepted: 06/02/2022] [Indexed: 02/05/2023] Open
Abstract
Macroautophagy/autophagy is an evolutionally conserved catabolic process in which cytosolic contents, such as aggregated proteins, dysfunctional organelle, or invading pathogens, are sequestered by the double‐membrane structure termed autophagosome and delivered to lysosome for degradation. Over the past two decades, autophagy has been extensively studied, from the molecular mechanisms, biological functions, implications in various human diseases, to development of autophagy‐related therapeutics. This review will focus on the latest development of autophagy research, covering molecular mechanisms in control of autophagosome biogenesis and autophagosome–lysosome fusion, and the upstream regulatory pathways including the AMPK and MTORC1 pathways. We will also provide a systematic discussion on the implication of autophagy in various human diseases, including cancer, neurodegenerative disorders (Alzheimer disease, Parkinson disease, Huntington's disease, and Amyotrophic lateral sclerosis), metabolic diseases (obesity and diabetes), viral infection especially SARS‐Cov‐2 and COVID‐19, cardiovascular diseases (cardiac ischemia/reperfusion and cardiomyopathy), and aging. Finally, we will also summarize the development of pharmacological agents that have therapeutic potential for clinical applications via targeting the autophagy pathway. It is believed that decades of hard work on autophagy research is eventually to bring real and tangible benefits for improvement of human health and control of human diseases.
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Affiliation(s)
- Guang Lu
- Department of Physiology, Zhongshan School of Medicine Sun Yat-sen University Guangzhou China
| | - Yu Wang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, and West China School of Basic Medical Sciences & Forensic Medicine Sichuan University and Collaborative Innovation Center for Biotherapy Chengdu China
| | - Yin Shi
- Department of Biochemistry Zhejiang University School of Medicine Hangzhou China
| | - Zhe Zhang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, and West China School of Basic Medical Sciences & Forensic Medicine Sichuan University and Collaborative Innovation Center for Biotherapy Chengdu China
| | - Canhua Huang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, and West China School of Basic Medical Sciences & Forensic Medicine Sichuan University and Collaborative Innovation Center for Biotherapy Chengdu China
| | - Weifeng He
- State Key Laboratory of Trauma, Burn and Combined Injury, Institute of Burn Research Southwest Hospital Army Medical University Chongqing China
| | - Chuang Wang
- Department of Pharmacology, Provincial Key Laboratory of Pathophysiology Ningbo University School of Medicine Ningbo Zhejiang China
| | - Han-Ming Shen
- Department of Biomedical Sciences, Faculty of Health Sciences, Ministry of Education Frontiers Science Center for Precision Oncology University of Macau Macau China
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Ryan JL, Sherman AK, Heble DE, Friesen CA, Daniel JF, Fischer RT, Slowik V. The effect of neuropsychiatric medication on pediatric nonalcoholic fatty liver disease. Clin Transl Sci 2022; 15:2241-2250. [PMID: 35769031 PMCID: PMC9468556 DOI: 10.1111/cts.13358] [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: 11/19/2021] [Revised: 05/13/2022] [Accepted: 06/01/2022] [Indexed: 01/25/2023] Open
Abstract
Obese and overweight children are at risk of developing nonalcoholic fatty liver disease (NAFLD), which can lead to steatohepatitis, cirrhosis, and liver transplantation. Neuropsychiatric conditions affect an increasing proportion of children and often require neuropsychiatric medications (NPMs) that are associated with weight gain and/or drug-induced liver injury. We sought to evaluate the role that the extended use of NPMs play in pediatric NAFLD. Medical chart review was conducted for 260 patients with NAFLD (NPM = 77, non-NPM = 183) seen in the Liver Care Center at Children's Mercy Hospital between 2000 and 2016. Outcome measures included body mass index (BMI) percentile, BMI z-score, aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, and gamma glutamyltransferase, and were collected at diagnosis, 6-18 month follow-up, and 18-36 months. Controlling for race and metformin, there was a significant increase over time in BMI z-score (p < 0.01) and total bilirubin (p = 0.03), with only initial decreases in ALT (p < 0.01) and AST (p < 0.01). Except for higher total bilirubin in the non-NPM group, no main effect of group or interaction effect was found. Similar patterns remained when subjects were analyzed by NPM drug class. Further study is needed to confirm these findings and to evaluate the effects of NPM dose and duration of exposure, by drug class, on pediatric NAFLD outcomes.
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Affiliation(s)
- Jamie L. Ryan
- Division of Pediatric Gastroenterology, Hepatology, and NutritionChildren’s Mercy HospitalKansas CityMissouriUSA,Division of Developmental and Behavioral HealthChildren’s Mercy HospitalKansas CityMissouriUSA
| | - Ashley K. Sherman
- Division of Health Services and Outcomes ResearchChildren’s Mercy HospitalKansas CityMissouriUSA
| | - Daniel E. Heble
- Department of PharmacyChildren’s Mercy HospitalKansas CityMissouriUSA
| | - Craig A. Friesen
- Division of Pediatric Gastroenterology, Hepatology, and NutritionChildren’s Mercy HospitalKansas CityMissouriUSA,Department of PediatricsUniversity of Missouri – Kansas City School of MedicineKansas CityMissouriUSA
| | - James F. Daniel
- Division of Pediatric Gastroenterology, Hepatology, and NutritionChildren’s Mercy HospitalKansas CityMissouriUSA,Department of PediatricsUniversity of Missouri – Kansas City School of MedicineKansas CityMissouriUSA
| | - Ryan T. Fischer
- Division of Pediatric Gastroenterology, Hepatology, and NutritionChildren’s Mercy HospitalKansas CityMissouriUSA,Department of PediatricsUniversity of Missouri – Kansas City School of MedicineKansas CityMissouriUSA
| | - Voytek Slowik
- Division of Pediatric Gastroenterology, Hepatology, and NutritionChildren’s Mercy HospitalKansas CityMissouriUSA,Department of PediatricsUniversity of Missouri – Kansas City School of MedicineKansas CityMissouriUSA
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43
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Morishita H, Komatsu M. Role of autophagy in liver diseases. CURRENT OPINION IN PHYSIOLOGY 2022. [DOI: 10.1016/j.cophys.2022.100594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Riemekasten G, Distler JH. A broad look into the future of systemic sclerosis. Ther Adv Musculoskelet Dis 2022; 14:1759720X221109404. [PMID: 35966183 PMCID: PMC9373175 DOI: 10.1177/1759720x221109404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 06/07/2022] [Indexed: 11/28/2022] Open
Abstract
Systemic sclerosis (SSc) is a systemic autoimmune disease with the key
features of inflammation, vasculopathy and fibrosis. This article
focussed on emerging fields based on the authors’ current work and
expertise. The authors provide a hierarchical structure into the
studies of the pathogenesis of SSc starting with the contribution of
environmental factors. Regulatory autoantibodies (abs) are discussed,
which are parts of the human physiology and are specifically
dysregulated in SSc. Abs against the angiotensin II receptor subtype 1
(AT1R) and the endothelin receptor type A (ETAR) are discussed in more
detail. Extracellular vesicles are another novel player to possess
disease processes. Fibroblasts are a key effector cell in SSc.
Therefore, the current review will provide an overview about their
plasticity in the phenotype and function. Promising nuclear receptors
as key regulators of transcriptional programmes will be introduced as
well as epigenetic modifications, which are pivotal to maintain the
profibrotic fibroblast phenotype independent of external stimuli.
Fibroblasts from SSc patients exhibit a specific signalling and
reactivate developmental pathways and stem cell maintenance such as by
employing hedgehog and WNT, which promote fibroblast-to-myofibroblast
transition and extracellular matrix generation. Pharmacological
interventions, although for other indications, are already in clinical
use to address pathologic signalling.
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Affiliation(s)
| | - Jörg H.W. Distler
- Department of Internal Medicine 3,
Universitätsklinikum Erlangen, Friedrich-Alexander-University
(FAU) Erlangen-Nürnberg, Erlangen, Germany
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Song E, Nagarapu A, van Nispen J, Armstrong A, Manithody C, Murali V, Voigt M, Samaddar A, Hutchinson C, Jain S, Roenker J, Krebs J, Jain AK. Carbamazepine mitigates parenteral nutrition-associated liver disease in a novel ambulatory piglet model. JPEN J Parenter Enteral Nutr 2022; 46:1384-1392. [PMID: 35072265 PMCID: PMC9308820 DOI: 10.1002/jpen.2330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 01/02/2022] [Accepted: 01/05/2022] [Indexed: 12/16/2022]
Abstract
BACKGROUND Parenteral nutrition (PN) remains a critical therapeutic option in patients who cannot tolerate enteral feeding. However, although lifesaving, PN is associated with significant side effects, including liver injury, the etiology of which is multifactorial. Carbamazepine (CBZ), an antiepileptic medication, is known to modulate hepatic fibrosis and hepatocellular injury in a variety of liver diseases. We hypothesized that CBZ could prevent PN-associated liver disease (PNALD), which we tested by using our novel ambulatory PN piglet model. METHODS Piglets were fitted with jugular catheters and infusion pumps for PN and randomized to enteral nutrition (n = 7), PN (n = 6), or PN with parenteral CBZ (n = 6) for 2 weeks. Serum and liver tissue were analyzed via light microscopy, quantification of serum liver injury markers, Ki67 and cytokeratin-7 indexing, and real-time quantitative polymerase chain reaction. RESULTS PN-fed piglets in our model developed manifestations of PNALD-particularly, increased serum bilirubin, gamma-glutamyltransferase, liver cholestasis, and Ki67 expression compared with that of EN-fed animals (P < 0.03). CBZ therapy in PN-fed animals led to a significant reduction in these markers of injury (P < 0.05). Investigation into the mechanism of these therapeutic effects revealed increased expression of sterol regulatory element-binding protein 1 (SREBP-1), peroxisome proliferator-activated receptor alpha (PPAR-α), and fatty acid binding protein (FABP) in PN-fed animals receiving CBZ (P < 0.03). Further investigation revealed increased LC3 expression and decreased lysosomal-associated membrane protein (LAMP1) expression with CBZ (P < 0.03). CONCLUSION CBZ administration mitigates PNALD severity, suggesting a novel therapeutic strategy targeting PN-associated side effects, and may present a paradigm change to current treatment options.
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Affiliation(s)
- Eric Song
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Aakash Nagarapu
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Johan van Nispen
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Austin Armstrong
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | | | - Vidul Murali
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Marcus Voigt
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Ashish Samaddar
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Chelsea Hutchinson
- Department of Surgery, St. Louis University School of Medicine, St. Louis, Missouri
| | - Sonali Jain
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Jeremy Roenker
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Joseph Krebs
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
| | - Ajay K Jain
- Department of Pediatrics, St. Louis University School of Medicine, St. Louis, Missouri
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Abstract
Liver disease in homozygous ZZ alpha-1 antitrypsin (AAT) deficiency occurs due to the accumulation of large quantities of AAT mutant Z protein polymers in the liver. The mutant Z protein folds improperly during biogenesis and is retained within the hepatocytes rather than appropriately secreted. These intracellular polymers trigger an injury cascade, which leads to liver injury. However, the clinical liver disease is highly variable and not all patients with this same homozygous ZZ genotype develop liver disease. Evidence suggests that genetic determinants of intracellular protein processing, among other unidentified genetic and environmental factors, likely play a role in liver disease susceptibility. Advancements made in development of new treatment strategies using siRNA technology, and other novel approaches, are promising, and multiple human liver disease trials are underway.
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Affiliation(s)
- Anandini Suri
- Division of Pediatric Gastroenetrology, Hepatology and Nutrition, Department of Pediatrics, Saint Louis University School of Medicine, SSM Health Cardinal Glennon Children's Hospital, 1465 S Grand Boulevard, St. Louis, MO 63104, USA.
| | - Dhiren Patel
- Division of Pediatric Gastroenetrology, Hepatology and Nutrition, Department of Pediatrics, Saint Louis University School of Medicine, SSM Health Cardinal Glennon Children's Hospital, 1465 S Grand Boulevard, St. Louis, MO 63104, USA
| | - Jeffrey H Teckman
- Division of Pediatric Gastroenetrology, Hepatology and Nutrition, Department of Pediatrics, Saint Louis University School of Medicine, SSM Health Cardinal Glennon Children's Hospital, 1465 S Grand Boulevard, St. Louis, MO 63104, USA
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Cell Autophagy in NASH and NASH-Related Hepatocellular Carcinoma. Int J Mol Sci 2022; 23:ijms23147734. [PMID: 35887082 PMCID: PMC9322157 DOI: 10.3390/ijms23147734] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 12/21/2022] Open
Abstract
Autophagy, a cellular self-digestion process, involves the degradation of targeted cell components such as damaged organelles, unfolded proteins, and intracellular pathogens by lysosomes. It is a major quality control system of the cell and plays an important role in cell differentiation, survival, development, and homeostasis. Alterations in the cell autophagic machinery have been implicated in several disease conditions, including neurodegeneration, autoimmunity, cancer, infection, inflammatory diseases, and aging. In non-alcoholic fatty liver disease, including its inflammatory form, non-alcoholic steatohepatitis (NASH), a decrease in cell autophagic activity, has been implicated in the initial development and progression of steatosis to NASH and hepatocellular carcinoma (HCC). We present an overview of autophagy as it occurs in mammalian cells with an insight into the emerging understanding of the role of autophagy in NASH and NASH-related HCC.
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Update Alpha-1-Antitrypsin-Mangel. Monatsschr Kinderheilkd 2022. [DOI: 10.1007/s00112-022-01549-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
ZusammenfassungDer Alpha-1-Antitrypsin-Mangel (AATM) ist mit einer Prävalenz bis zu 1:2000 eine der häufigsten monogenetischen Ursachen für eine Lebertransplantation im Kindesalter. Pulmonal manifestiert sich der AATM erst im Erwachsenenalter. Er wird oft zu spät oder überhaupt nicht diagnostiziert. Die initiale Diagnostik ist mit einer Serumspiegelbestimmung einfach und günstig durchführbar. Bei Werten unter 1,1 g/l sollte eine Genotypisierung erfolgen, die im Alpha-1-Antitrypsin-Zentrum Marburg kostenfrei angeboten wird. Aufgrund des sehr heterogenen Verlaufs sollte die weiterführende Betreuung von Patienten mit AATM jedoch Spezialisten mit ausreichender Erfahrung vorbehalten bleiben. Hierfür eignen sich insbesondere die pädiatrischen Alpha-1-Center. Einen hohen Stellenwert haben die Aufklärung sowie die Aufrechterhaltung einer guten Compliance mit regelmäßigen ärztlichen Verlaufskontrollen, um eine Progredienz der Lebererkrankung zu erfassen. Neben Anamnese und körperlicher Untersuchung sind regelmäßige Blutentnahmen und Ultraschalluntersuchungen (inkl. Leberelastographie) notwendig. Therapeutisch stehen neben einer kurativen Lebertransplantation derzeit lediglich supportive Therapien zur Wahl. Sollte eine Lebertransplantation indiziert sein, ist das Langzeit-Outcome erfreulicherweise sehr gut.
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Takehana S, Yang W, Tabata Y. Potential Method of Autophagy Imaging with Cationized Gelatin Nanospheres Incorporating Molecular Beacon. ACS APPLIED BIO MATERIALS 2022; 5:2965-2975. [PMID: 35609115 DOI: 10.1021/acsabm.2c00287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The objective of this research is to develop an imaging method with cationized gelatin nanospheres incorporating molecular beacon (cGNSMB) to visualize an autophagy activity in living cells. Cationized gelatin nanospheres (cGNS) were prepared by the conventional coacervation method, and then molecular beacon (MB) was incorporated into them. The cGNSMB prepared were internalized into cells at a high efficiency. In this study, a starvation medium of serum and amino acids-free was used to induce autophagy. The autophagy activity was confirmed by an immunofluorescence staining for microtubule-associated proteins light chain 3B (LC3B) of an autophagy specific protein. With the autophagy induction time, the number of LC3 fluorescent dots increased, which indicated an increased autophagy activity. As the autophagy-related genes, sequestosome 1 (SQSTM1) and cathepsin F (CTSF), which up-regulate after autophagy induction, were chosen as the targets of cGNSMB. The fluorescence intensity of cGNSMB targeting to SQSTM1 and CTSF increased with the starvation treatment time, which well corresponded with the gene expression results. When applied to cells in different autophagy conditions, the cGNSMB visualized the autophagy activity corresponding with the autophagy condition of cells. From the results obtained, it was concluded that the cGNSMB provide a promising method to visualize the autophagy of cells. The advantage of cGNSMB visualization is to obtain the temporal and spatial information without destroying sample cells.
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Affiliation(s)
- Sho Takehana
- Laboratory of Biomaterials, Institute for Life and Medical Sciences, Kyoto University, Kawahara-cho Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Wenxuan Yang
- Laboratory of Biomaterials, Institute for Life and Medical Sciences, Kyoto University, Kawahara-cho Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Yasuhiko Tabata
- Laboratory of Biomaterials, Institute for Life and Medical Sciences, Kyoto University, Kawahara-cho Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
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Lin CH, Lin YC, Yang SB, Chen PC. Carbamazepine promotes surface expression of mutant Kir6.2-A28V ATP-sensitive potassium channels by modulating Golgi retention and autophagy. J Biol Chem 2022; 298:101904. [PMID: 35398096 PMCID: PMC9065613 DOI: 10.1016/j.jbc.2022.101904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 03/25/2022] [Accepted: 03/27/2022] [Indexed: 11/21/2022] Open
Abstract
Pancreatic β-cells express ATP-sensitive potassium (KATP) channels, consisting of octamer complexes containing four sulfonylurea receptor 1 (SUR1) and four Kir6.2 subunits. Loss of KATP channel function causes persistent hyperinsulinemic hypoglycemia of infancy (PHHI), a rare but debilitating condition if not treated. We previously showed that the sodium-channel blocker carbamazepine (Carb) corrects KATP channel surface expression defects induced by PHHI-causing mutations in SUR1. In this study, we show that Carb treatment can also ameliorate the trafficking deficits associated with a recently discovered PHHI-causing mutation in Kir6.2 (Kir6.2-A28V). In human embryonic kidney 293 or INS-1 cells expressing this mutant KATP channel (SUR1 and Kir6.2-A28V), biotinylation and immunostaining assays revealed that Carb can increase surface expression of the mutant KATP channels. We further examined the subcellular distributions of mutant KATP channels before and after Carb treatment; without Carb treatment, we found that mutant KATP channels were aberrantly accumulated in the Golgi apparatus. However, after Carb treatment, coimmunoprecipitation of mutant KATP channels and Golgi marker GM130 was diminished, and KATP staining was also reduced in lysosomes. Intriguingly, Carb treatment also simultaneously increased autophagic flux and p62 accumulation, suggesting that autophagy-dependent degradation of the mutant channel was not only stimulated but also interrupted. In summary, our data suggest that surface expression of Kir6.2-A28V KATP channels is rescued by Carb treatment via promotion of mutant KATP channel exit from the Golgi apparatus and reduction of autophagy-mediated protein degradation.
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