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Denk H, Abuja PM, Zatloukal K. Mallory-Denk bodies and hepatocellular senescence: a causal relationship? Virchows Arch 2024; 484:637-644. [PMID: 38289501 PMCID: PMC11063002 DOI: 10.1007/s00428-024-03748-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 01/17/2024] [Accepted: 01/22/2024] [Indexed: 05/02/2024]
Abstract
Mallory-Denk bodies (MDBs) are hepatocellular cytoplasmic inclusions, which occur in certain chronic liver diseases, such as alcohol-related (ASH) and metabolic dysfunction-associated (MASH) steatohepatitis, copper toxicosis, some drug-induced liver disorders, chronic cholangiopathies, and liver tumors. Our study focused on the expression of the senescence markers p21WAF1/cip1 and p16INK4a in hepatocytes containing MDBs in steatohepatitis, chronic cholangiopathies with fibrosis or cirrhosis, Wilson's disease, and hepatocellular carcinomas. Cytoplasm and nuclei of MDB-containing hepatocytes as well as MDB inclusions, except those associated with carcinoma cells, were strongly p16-positive, p21-positive, as well as p21-negative nuclei in MDB-containing hepatocytes which were observed whereas MDBs were p21-negative. Expression of the senescence marker p16 suggests that MDB formation reflects an adaptive response to chronic stress resembling senescence with its consequences, i.e., expression of inflammation- and fibrosis-prone secretome. Thus, senescence can be regarded as "double-edged sword" since, on the one hand, it may be an attempt of cellular defense, but, on the other, also causes further and sustained damage by inducing inflammation and fibrosis related to the senescence-associated secretory phenotype and thus progression of chronic liver disease.
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Affiliation(s)
- Helmut Denk
- Diagnostic and Research Institute of Pathology, Diagnostic & Research Center of Molecular Biomedicine, Medical University of Graz, Neue Stiftingtalstrasse 6, A-8010, Graz, Austria.
| | - Peter M Abuja
- Diagnostic and Research Institute of Pathology, Diagnostic & Research Center of Molecular Biomedicine, Medical University of Graz, Neue Stiftingtalstrasse 6, A-8010, Graz, Austria
| | - Kurt Zatloukal
- Diagnostic and Research Institute of Pathology, Diagnostic & Research Center of Molecular Biomedicine, Medical University of Graz, Neue Stiftingtalstrasse 6, A-8010, Graz, Austria
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2
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Qian H, Ding WX. SQSTM1/p62 and Hepatic Mallory-Denk Body Formation in Alcohol-Associated Liver Disease. THE AMERICAN JOURNAL OF PATHOLOGY 2023; 193:1415-1426. [PMID: 36906265 PMCID: PMC10642158 DOI: 10.1016/j.ajpath.2023.02.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/14/2023] [Accepted: 02/24/2023] [Indexed: 03/12/2023]
Abstract
Sequestosome 1 (SQSTM1/p62; hereafter p62) is an autophagy receptor protein for selective autophagy primarily due to its direct interaction with the microtubule light chain 3 protein that specifically localizes on autophagosome membranes. As a result, impaired autophagy leads to the accumulation of p62. p62 is also a common component of many human liver disease-related cellular inclusion bodies, such as Mallory-Denk bodies, intracytoplasmic hyaline bodies, α1-antitrypsin aggregates, as well as p62 bodies and condensates. p62 also acts as an intracellular signaling hub, and it involves multiple signaling pathways, including nuclear factor erythroid 2-related factor 2, NF-κB, and the mechanistic target of rapamycin, which are critical for oxidative stress, inflammation, cell survival, metabolism, and liver tumorigenesis. This review discusses the recent insights of p62 in protein quality control, including the role of p62 in the formation and degradation of p62 stress granules and protein aggregates as well as regulation of multiple signaling pathways in the pathogenesis of alcohol-associated liver disease.
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Affiliation(s)
- Hui Qian
- Department of Pharmacology, Toxicology, and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas
| | - Wen-Xing Ding
- Department of Pharmacology, Toxicology, and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas; Department of Internal Medicine, The University of Kansas Medical Center, Kansas City, Kansas.
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3
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Iwai S, Kaji K, Nishimura N, Kubo T, Tomooka F, Shibamoto A, Suzuki J, Tsuji Y, Fujinaga Y, Kitagawa K, Namisaki T, Akahane T, Yoshiji H. Glucagon-like peptide-1 receptor agonist, semaglutide attenuates chronic liver disease-induced skeletal muscle atrophy in diabetic mice. Biochim Biophys Acta Mol Basis Dis 2023:166770. [PMID: 37276988 DOI: 10.1016/j.bbadis.2023.166770] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 05/15/2023] [Accepted: 05/28/2023] [Indexed: 06/07/2023]
Abstract
A glucagon-like peptide-1 receptor agonist (GLP-1RA) has recently been established as a pharmacological option for the treatment of type 2 diabetes. Recent studies have demonstrated the molecular role of GLP-1R in skeletal muscle homeostasis; however, the therapeutic efficacy of semaglutide, a GLP-1RA, on skeletal muscle atrophy in chronic liver disease (CLD) under diabetic conditions remains unclear. In the present study, semaglutide effectively inhibited psoas muscle atrophy and suppressed declines in grip strength in a diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet-fed diabetic KK-Ay mouse model. Moreover, semaglutide inhibited ubiquitin-proteosome-mediated skeletal muscle proteolysis and promoted myogenesis in palmitic acid (PA)-stimulated C2C12 murine myocytes. Mechanistically, this effect of semaglutide on skeletal muscle atrophy was mediated by multiple functional pathways. First, semaglutide protected against hepatic injury in mice accompanied by increased production of insulin-like growth factor 1 and reduced accumulation of reactive oxygen species (ROS). These effects were associated with decreased proinflammatory cytokines and ROS accumulation, leading to the suppression of ubiquitin-proteosome muscle degradation. Moreover, semaglutide inhibited the amino acid starvation-related stress signaling that was activated under chronic liver injury, resulting in the recovery of the mammalian target of rapamycin activity in the skeletal muscle of DDC-diet fed KK-Ay mice. Second, semaglutide improved skeletal muscle atrophy by directly stimulating GLP-1R in myocytes. Semaglutide induced cAMP-mediated activation of PKA and AKT, enhanced mitochondrial biogenesis, and reduced ROS accumulation, thereby resulting in inhibition of NF-κB/myostatin-mediated ubiquitin-proteosome degradation and the augmentation of heat-shock factor-1-mediated myogenesis. Collectively, semaglutide may have potential as a new therapeutic strategy for CLD-related skeletal muscle wasting.
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Affiliation(s)
- Satoshi Iwai
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Kosuke Kaji
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan.
| | - Norihisa Nishimura
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Takahiro Kubo
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Fumimasa Tomooka
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Akihiko Shibamoto
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Junya Suzuki
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Yuki Tsuji
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Yukihisa Fujinaga
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Koh Kitagawa
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Tadashi Namisaki
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Takemi Akahane
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | - Hitoshi Yoshiji
- Department of Gastroenterology, Nara Medical University, Kashihara, Nara 634-8521, Japan
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4
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Priming, Triggering, Adaptation and Senescence (PTAS): A Hypothesis for a Common Damage Mechanism of Steatohepatitis. Int J Mol Sci 2021; 22:ijms222212545. [PMID: 34830427 PMCID: PMC8624051 DOI: 10.3390/ijms222212545] [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: 09/30/2021] [Revised: 11/18/2021] [Accepted: 11/19/2021] [Indexed: 11/17/2022] Open
Abstract
Understanding the pathomechanism of steatohepatitis (SH) is hampered by the difficulty of distinguishing between causes and consequences, by the broad spectrum of aetiologies that can produce the phenotype, and by the long time-span during which SH develops, often without clinical symptoms. We propose that SH develops in four phases with transitions: (i) priming lowers stress defence; (ii) triggering leads to acute damage; (iii) adaptation, possibly associated with cellular senescence, mitigates tissue damage, leads to the phenotype, and preserves liver function at a lower level; (iv) finally, senescence prevents neoplastic transformation but favours fibrosis (cirrhosis) and inflammation and further reduction in liver function. Escape from senescence eventually leads to hepatocellular carcinoma. This hypothesis for a pathomechanism of SH is supported by clinical and experimental observations. It allows organizing the various findings to uncover remaining gaps in our knowledge and, finally, to provide possible diagnostic and intervention strategies for each stage of SH development.
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Gu YF, Chen YP, Jin R, Wang C, Wen C, Zhou YM. Age-related changes in liver metabolism and antioxidant capacity of laying hens. Poult Sci 2021; 100:101478. [PMID: 34695635 PMCID: PMC8554276 DOI: 10.1016/j.psj.2021.101478] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 08/30/2021] [Accepted: 09/09/2021] [Indexed: 02/07/2023] Open
Abstract
This study aimed to investigate the age-related changes of hepatic metabolism and antioxidant capacity of laying hens at 3 different ages. A total of 192 Hy-line Brown laying hens were assigned into 3 groups: 1) 195-day-old (D195 group); 2) 340-day-old (D340 group); 3) 525-day-old (D525 group). Each group replicated 8 times with 8 hens at the same age. Higher activity of aspartate aminotransferase and lower contents of total protein and globulin were observed in the serum of 525-day-old hens in comparison with their 195-day-old counterparts (P < 0.05). The 525-day-old hens accumulated higher contents of total cholesterol and triglyceride in the liver than 195-day-old birds. Additionally, compared with hens from D195 or D340 group, 525-day-old birds exhibited a lower circulating estradiol level (P < 0.05). For antioxidant capacity, birds in the D525 group showed a higher malondialdehyde concentration in both serum and liver as compared with D195 or D340 group (P < 0.05). The 525-day-old hens also exhibited lower glutathione peroxidase activities in both serum and liver when compared with 195-day-old birds (P < 0.05). Simultaneously, there was a decline of hepatic superoxide dismutase activity in the D525 group in comparison with D195 group (P < 0.05). Compared with 195-day-old counterparts, 340-day-old birds upregulated the mRNA abundance of nuclear factor erythroid-2 related factor 2 and glutathione peroxidase 1 in the liver (P < 0.05). In contrast, hens from D525 group showed the downregulation of hepatic nuclear factor erythroid-2 related factor 2, NAD(P)H quinone dehydrogenase 1, and superoxide dismutase 1 when compared with D340 group (P < 0.05). These results indicated that increasing age can adversely affect liver metabolism and function of laying hens.
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Affiliation(s)
- Y F Gu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Y P Chen
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - R Jin
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - C Wang
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - C Wen
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Y M Zhou
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, P. R. China.
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D'Eletto M, Rossin F, Fedorova O, Farrace MG, Piacentini M. Transglutaminase type 2 in the regulation of proteostasis. Biol Chem 2019; 400:125-140. [PMID: 29908126 DOI: 10.1515/hsz-2018-0217] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 05/15/2018] [Indexed: 12/21/2022]
Abstract
The maintenance of protein homeostasis (proteostasis) is a fundamental aspect of cell physiology that is essential for the survival of organisms under a variety of environmental and/or intracellular stress conditions. Acute and/or persistent stress exceeding the capacity of the intracellular homeostatic systems results in protein aggregation and/or damaged organelles that leads to pathological cellular states often resulting in cell death. These events are continuously suppressed by a complex macromolecular machinery that uses different intracellular pathways to maintain the proteome integrity in the various subcellular compartments ensuring a healthy cellular life span. Recent findings have highlighted the role of the multifunctional enzyme type 2 transglutaminase (TG2) as a key player in the regulation of intracellular pathways, such as autophagy/mitophagy, exosomes formation and chaperones function, which form the basis of proteostasis regulation under conditions of cellular stress. Here, we review the role of TG2 in these stress response pathways and how its various enzymatic activities might contributes to the proteostasis control.
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Affiliation(s)
- Manuela D'Eletto
- Department of Biology, University of Rome 'Tor Vergata', Via della Ricerca Scientifica, I-00133 Rome, Italy
| | - Federica Rossin
- Department of Biology, University of Rome 'Tor Vergata', Via della Ricerca Scientifica, I-00133 Rome, Italy
| | - Olga Fedorova
- Institute of Cytology, 194064 Saint-Petersburg, Russia
| | - Maria Grazia Farrace
- Department of Biology, University of Rome 'Tor Vergata', Via della Ricerca Scientifica, I-00133 Rome, Italy
| | - Mauro Piacentini
- Department of Biology, University of Rome 'Tor Vergata', Via della Ricerca Scientifica, I-00133 Rome, Italy.,National Institute for Infectious Diseases I.R.C.C.S. 'Lazzaro Spallanzani', I-00149 Rome, Italy
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7
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High-fat and high-cholesterol diet decreases phosphorylated inositol-requiring kinase-1 and inhibits autophagy process in rat liver. Sci Rep 2019; 9:12514. [PMID: 31467308 PMCID: PMC6715744 DOI: 10.1038/s41598-019-48973-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 08/14/2019] [Indexed: 12/19/2022] Open
Abstract
Precise molecular pathways involved in the progression of non-alcoholic steatohepatitis (NASH) remain to be elucidated. As Mallory–Denk bodies were occasionally observed in the enlarged hepatocytes in NASH model rat (SHRSP5/Dmcr) fed high-fat and high-cholesterol (HFC) diet, we aimed to clarify the roles of autophagy and endoplasmic reticulum (ER) stress in NASH progression. Male SHRSP5/Dmcr were randomly divided into 4 groups. Two groups were fed a control diet; the other two groups were fed a HFC diet for 2 and 8 weeks, respectively. The HFC diet increased the autophagy-related proteins levels and microtubule-associated protein 1 light chain 3-II/I ratio after 2 and 8 weeks, respectively. However, regarding ER stress-related proteins, the HFC diet decreased the levels of phosphorylated (p-) inositol-requiring kinase-1 (p-IRE-1) and p-protein kinase RNA-like ER kinase after 2 weeks. Additionally, the HFC diet increased anti-ubiquitin-positive cells and the level of the autophagy substrate p62, suggesting that the HFC diet induced dysfunction in ubiquitin-dependent protein degradation pathways. In conclusion, the HFC diet arrested the autophagy process in the liver; this was particularly associated with decreases in p-IRE-1 expression.
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8
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Animal models of NAFLD from the pathologist's point of view. Biochim Biophys Acta Mol Basis Dis 2018; 1865:929-942. [PMID: 29746920 DOI: 10.1016/j.bbadis.2018.04.024] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 04/25/2018] [Accepted: 04/30/2018] [Indexed: 01/18/2023]
Abstract
Fatty liver disease is a multifactorial world-wide health problem resulting from a complex interplay between liver, adipose tissue and intestine and initiated by alcohol abuse, overeating, various types of intoxication, adverse drug reactions and genetic or acquired metabolic defects. Depending on etiology fatty liver disease is commonly categorized as alcoholic or non-alcoholic. Both types may progress from simple steatosis to the necro-inflammatory lesion of alcoholic (ASH) and non-alcoholic steatohepatitis (NASH), respectively, and finally to cirrhosis and hepatocellular carcinoma. Animal models are helpful to clarify aspects of pathogenesis and progression. Generally, they are classified as nutritional (dietary), toxin-induced and genetic, respectively, or represent a combination of these factors. Numerous reviews are dealing with NASH animal models designed to imitate as closely as possible the metabolic situation associated with human disease. This review focuses on currently used mouse models of NASH with particular emphasis on liver morphology. Despite metabolic similarities most models (except those with chemically or genetically induced porphyria or keratin 18-deficiency) fail to develop the morphologic key features of NASH, namely hepatocyte ballooning and formation of histologically and immunohistochemically well-defined Mallory-Denk-Bodies (MDBs). Although MDBs are not universally detectable in ballooned hepatocytes in NASH their experimental reproduction and analysis may, however, significantly contribute to our understanding of important pathogenic aspects of NASH despite the obvious differences in etiology.
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9
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Basisty NB, Liu Y, Reynolds J, Karunadharma PP, Dai DF, Fredrickson J, Beyer RP, MacCoss MJ, Rabinovitch PS. Stable Isotope Labeling Reveals Novel Insights Into Ubiquitin-Mediated Protein Aggregation With Age, Calorie Restriction, and Rapamycin Treatment. J Gerontol A Biol Sci Med Sci 2018; 73:561-570. [PMID: 28958078 PMCID: PMC6380815 DOI: 10.1093/gerona/glx047] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 08/16/2017] [Indexed: 12/30/2022] Open
Abstract
Accumulation of protein aggregates with age was first described in aged human tissue over 150 years ago and has since been described in virtually every human tissue. Ubiquitin modifications are a canonical marker of insoluble protein aggregates; however, the composition of most age-related inclusions remains relatively unknown. To examine the landscape of age-related protein aggregation in vivo, we performed an antibody-based pulldown of ubiquitinated proteins coupled with metabolic labeling and mass spectrometry on young and old mice on calorie restriction (CR), rapamycin (RP)-supplemented, and control diets. We show increased abundance of many ubiquitinated proteins in old mice and greater retention of preexisting (unlabeled) ubiquitinated proteins relative to their unmodified counterparts-fitting the expected profile of age-increased accumulation of long-lived aggregating proteins. Both CR and RP profoundly affected ubiquitinome composition, half-live, and the insolubility of proteins, consistent with their ability to mobilize these age-associated accumulations. Finally, confocal microscopy confirmed the aggregation of two of the top predicted aggregating proteins, keratins 8/18 and catalase, as well as their attenuation by CR and RP. Stable-isotope labeling is a powerful tool to gain novel insights into proteostasis mechanisms, including protein aggregation, and could be used to identify novel therapeutic targets in aging and protein aggregation diseases.
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Affiliation(s)
- Nathan B Basisty
- Department of Pathology, University of Washington, Seattle
- Buck Institute for Research on Aging, Novato, California
| | - Yuxin Liu
- Department of Medicine, SUNY Upstate Medical University, Syracuse, New York
| | - Jason Reynolds
- Department of Medicine, University of Washington, Seattle
| | | | - Dao-Fu Dai
- Department of Pathology, University of Washington, Seattle
- Department of Pathology, University of Iowa Carver College of Medicine, Iowa City
| | | | - Richard P Beyer
- Department of Environmental Health, University of Washington, Seattle
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Bettermann K, Mehta AK, Hofer EM, Wohlrab C, Golob-Schwarzl N, Svendova V, Schimek MG, Stumptner C, Thüringer A, Speicher MR, Lackner C, Zatloukal K, Denk H, Haybaeck J. Keratin 18-deficiency results in steatohepatitis and liver tumors in old mice: A model of steatohepatitis-associated liver carcinogenesis. Oncotarget 2016; 7:73309-73322. [PMID: 27689336 PMCID: PMC5341981 DOI: 10.18632/oncotarget.12325] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 09/19/2016] [Indexed: 02/06/2023] Open
Abstract
Backround: Steatohepatitis (SH)-associated liver carcinogenesis is an increasingly important issue in clinical medicine. SH is morphologically characterized by steatosis, hepatocyte injury, ballooning, hepatocytic cytoplasmic inclusions termed Mallory-Denk bodies (MDBs), inflammation and fibrosis. RESULTS 17-20-months-old Krt18-/- and Krt18+/- mice in contrast to wt mice spontaneously developed liver lesions closely resembling the morphological spectrum of human SH as well as liver tumors. The pathologic alterations were more pronounced in Krt18-/- than in Krt18+/- mice. The frequency of liver tumors with male predominance was significantly higher in Krt18-/- compared to age-matched Krt18+/- and wt mice. Krt18-deficient tumors in contrast to wt animals displayed SH features and often pleomorphic morphology. aCGH analysis of tumors revealed chromosomal aberrations in Krt18-/- liver tumors, affecting loci of oncogenes and tumor suppressor genes. MATERIALS AND METHODS Livers of 3-, 6-, 12- and 17-20-months-old aged wild type (wt), Krt18+/- and Krt18-/- (129P2/OlaHsd background) mice were analyzed by light and immunofluorescence microscopy as well as immunohistochemistry. Liver tumors arising in aged mice were analyzed by array comparative genomic hybridization (aCGH). CONCLUSIONS Our findings show that K18 deficiency of hepatocytes leads to steatosis, increasing with age, and finally to SH. K18 deficiency and age promote liver tumor development in mice, frequently on the basis of chromosomal instability, resembling human HCC with stemness features.
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Affiliation(s)
- Kira Bettermann
- Institute of Pathology, Medical University of Graz, Graz 8036, Austria
| | | | - Eva M. Hofer
- Institute of Pathology, Medical University of Graz, Graz 8036, Austria
| | - Christina Wohlrab
- Institute of Pathology, Medical University of Graz, Graz 8036, Austria
| | | | - Vendula Svendova
- Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, Graz 8036, Austria
| | - Michael G. Schimek
- Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, Graz 8036, Austria
| | | | - Andrea Thüringer
- Institute of Pathology, Medical University of Graz, Graz 8036, Austria
| | | | - Carolin Lackner
- Institute of Pathology, Medical University of Graz, Graz 8036, Austria
| | - Kurt Zatloukal
- Institute of Pathology, Medical University of Graz, Graz 8036, Austria
| | - Helmut Denk
- Institute of Pathology, Medical University of Graz, Graz 8036, Austria
| | - Johannes Haybaeck
- Institute of Pathology, Medical University of Graz, Graz 8036, Austria
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11
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Schneider JL, Villarroya J, Diaz‐Carretero A, Patel B, Urbanska AM, Thi MM, Villarroya F, Santambrogio L, Cuervo AM. Loss of hepatic chaperone-mediated autophagy accelerates proteostasis failure in aging. Aging Cell 2015; 14:249-64. [PMID: 25620427 PMCID: PMC4364837 DOI: 10.1111/acel.12310] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2014] [Indexed: 12/15/2022] Open
Abstract
Chaperone-mediated autophagy (CMA), a cellular process that contributes to protein quality control through targeting of a subset of cytosolic proteins to lysosomes for degradation, undergoes a functional decline with age. We have used a mouse model with liver-specific defective CMA to identify changes in proteostasis attributable to reduced CMA activity in this organ with age. We have found that other proteolytic systems compensate for CMA loss in young mice which helps to preserve proteostasis. However, these compensatory responses are not sufficient for protection against proteotoxicity induced by stress (oxidative stress, lipid challenges) or associated with aging. Livers from old mice with CMA blockage exhibit altered protein homeostasis, enhanced susceptibility to oxidative stress and hepatic dysfunction manifested by a diminished ability to metabolize drugs, and a worsening of the metabolic dysregulation identified in young mice. Our study reveals that while the regulatory function of CMA cannot be compensated for in young organisms, its contribution to protein homeostasis can be handled by other proteolytic systems. However, the decline in the compensatory ability identified with age explains the more severe consequences of CMA impairment in older organisms and the contribution of CMA malfunction to the gradual decline in proteostasis and stress resistance observed during aging.
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Affiliation(s)
- Jaime L. Schneider
- Department of Developmental and Molecular BiologyAlbert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461 USA
- Institute for Aging Studies Albert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461USA
| | - Joan Villarroya
- Department of Developmental and Molecular BiologyAlbert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461 USA
- Institute for Aging Studies Albert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461USA
- Hospital de la Santa Creu i Sant Pau Av. Sant Antoni Maria Claret 167 Barcelona 08025Spain
| | - Antonio Diaz‐Carretero
- Department of Developmental and Molecular BiologyAlbert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461 USA
- Institute for Aging Studies Albert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461USA
| | - Bindi Patel
- Department of Developmental and Molecular BiologyAlbert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461 USA
- Institute for Aging Studies Albert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461USA
| | - Aleksandra M. Urbanska
- Department of PathologyAlbert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461 USA
| | - Mia M. Thi
- Department of Neuroscience Albert Einstein College of Medicine 1300 Morris Park AveBronx NY 10461USA
| | - Francesc Villarroya
- Department of Biochemistry and Molecular Biology University of Barcelona, and CIBER Fisiopatologia Obesidad y Nutrición Av. Diagonal, 643 Barcelona 08028Spain
| | - Laura Santambrogio
- Institute for Aging Studies Albert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461USA
- Department of PathologyAlbert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461 USA
| | - Ana Maria Cuervo
- Department of Developmental and Molecular BiologyAlbert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461 USA
- Institute for Aging Studies Albert Einstein College of Medicine 1300 Morris Park Ave Bronx NY 10461USA
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12
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Strnad P, Nuraldeen R, Guldiken N, Hartmann D, Mahajan V, Denk H, Haybaeck J. Broad Spectrum of Hepatocyte Inclusions in Humans, Animals, and Experimental Models. Compr Physiol 2013; 3:1393-436. [DOI: 10.1002/cphy.c120032] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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