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Medina-Vera I, Avila-Nava A, León-López L, Gutiérrez-Solis AL, Talamantes-Gómez JM, Márquez-Mota CC. Plant-based proteins: clinical and technological importance. Food Sci Biotechnol 2024; 33:2461-2475. [PMID: 39144188 PMCID: PMC11319542 DOI: 10.1007/s10068-024-01600-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 04/10/2024] [Accepted: 05/10/2024] [Indexed: 08/16/2024] Open
Abstract
Healthy and sustainable diets have seen a surge in popularity in recent years, driven by a desire to consume foods that not only help health but also have a favorable influence on the environment, such as plant-based proteins. This has created controversy because plant-based proteins may not always contain all the amino acids required by the organism. However, protein extraction methods have been developed due to technological advancements to boost their nutritional worth. Furthermore, certain chemicals, such as bioactive peptides, have been identified and linked to favorable health effects. As a result, the current analysis focuses on the primary plant-based protein sources, their chemical composition, and the molecular mechanism activated by the amino acid types of present. It also discusses plant protein extraction techniques, bioactive substances derived from these sources, product development using plant protein, and the therapeutic benefits of these plant-based proteins in clinical research.
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Affiliation(s)
- Isabel Medina-Vera
- Departamento de Metodología de la Investigación, Instituto Nacional de Pediatría (INP), Mexico City, Mexico
| | - Azalia Avila-Nava
- Hospital Regional de Alta Especialidad de la Península de Yucatán, Mérida, Mexico
| | - Liliana León-López
- Programa de Posgrado Integral en Biotecnología, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Sinaloa, C.P. 80000 Culiacán, Sinaloa Mexico
| | | | - José Moisés Talamantes-Gómez
- Departamento de Nutrición Animal y Bioquímica, Facultad de Medicina Veterinaria y Zootecnia (FMVZ), Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Claudia C. Márquez-Mota
- Departamento de Nutrición Animal y Bioquímica, Facultad de Medicina Veterinaria y Zootecnia (FMVZ), Universidad Nacional Autónoma de México, Mexico City, Mexico
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Taeb S, Rostamzadeh D, Amini SM, Rahmati M, Eftekhari M, Safari A, Najafi M. MicroRNAs targeted mTOR as therapeutic agents to improve radiotherapy outcome. Cancer Cell Int 2024; 24:233. [PMID: 38965615 PMCID: PMC11229485 DOI: 10.1186/s12935-024-03420-3] [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: 11/03/2023] [Accepted: 06/22/2024] [Indexed: 07/06/2024] Open
Abstract
MicroRNAs (miRNAs) are small RNA molecules that regulate genes and are involved in various biological processes, including cancer development. Researchers have been exploring the potential of miRNAs as therapeutic agents in cancer treatment. Specifically, targeting the mammalian target of the rapamycin (mTOR) pathway with miRNAs has shown promise in improving the effectiveness of radiotherapy (RT), a common cancer treatment. This review provides an overview of the current understanding of miRNAs targeting mTOR as therapeutic agents to enhance RT outcomes in cancer patients. It emphasizes the importance of understanding the specific miRNAs that target mTOR and their impact on radiosensitivity for personalized cancer treatment approaches. The review also discusses the role of mTOR in cell homeostasis, cell proliferation, and immune response, as well as its association with oncogenesis. It highlights the different ways in which miRNAs can potentially affect the mTOR pathway and their implications in immune-related diseases. Preclinical findings suggest that combining mTOR modulators with RT can inhibit tumor growth through anti-angiogenic and anti-vascular effects, but further research and clinical trials are needed to validate the efficacy and safety of using miRNAs targeting mTOR as therapeutic agents in combination with RT. Overall, this review provides a comprehensive understanding of the potential of miRNAs targeting mTOR to enhance RT efficacy in cancer treatment and emphasizes the need for further research to translate these findings into improved clinical outcomes.
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Affiliation(s)
- Shahram Taeb
- Department of Radiology, School of Paramedical Sciences, Guilan University of Medical Sciences, Rasht, Iran
| | - Davoud Rostamzadeh
- Department of Immunology, University of Connecticut Health Center, Farmington, CT, USA
| | - Seyed Mohammad Amini
- Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Rahmati
- Department of Medical Biotechnology, Faculty of Paramedicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Mohammad Eftekhari
- Department of Medical Biotechnology, Faculty of Paramedicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Arash Safari
- Department of Radiology, Ionizing and Non-Ionizing Radiation Protection Research Center (INIRPRC), School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, 71439-14693, Iran
| | - Masoud Najafi
- Radiology and Nuclear Medicine Department, School of Paramedical Sciences, Kermanshah University of Medical Sciences, Kermanshah, Iran.
- Medical Biology Research Center, Institute of Health Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran.
- Medical Technology Research Center, Institute of Health Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran.
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Xiong H, Zhang Y, Zhao Z, Sha Q. Whole-genome SNP allele frequency differences between Tibetan and Large white pigs reveal genes associated with skeletal muscle growth. BMC Genomics 2024; 25:588. [PMID: 38862895 PMCID: PMC11167949 DOI: 10.1186/s12864-024-10508-7] [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: 10/21/2023] [Accepted: 06/06/2024] [Indexed: 06/13/2024] Open
Abstract
BACKGROUND The skeletal muscle growth rate and body size of Tibetan pigs (TIB) are lower than Large white pigs (LW). However, the underlying genetic basis attributing to these differences remains uncertain. To address this knowledge gap, the present study employed whole-genome sequencing of TIB (slow growth) and LW (fast growth) individuals, and integrated with existing NCBI sequencing datasets of TIB and LW individuals, enabling the identification of a comprehensive set of genetic variations for each breed. The specific and predominant SNPs in the TIB and LW populations were detected by using a cutoff value of 0.50 for SNP allele frequency and absolute allele frequency differences (△AF) between the TIB and LW populations. RESULTS A total of 21,767,938 SNPs were retrieved from 44 TIB and 29 LW genomes. The analysis detected 2,893,106 (13.29%) and 813,310 (3.74%) specific and predominant SNPs in the TIB and LW populations, and annotated to 24,560 genes. Further GO analysis revealed 291 genes involved in biological processes related to striated and/or skeletal muscle differentiation, proliferation, hypertrophy, regulation of striated muscle cell differentiation and proliferation, and myoblast differentiation and fusion. These 291 genes included crucial regulators of muscle cell determination, proliferation, differentiation, and hypertrophy, such as members of the Myogenic regulatory factors (MRF) (MYOD, MYF5, MYOG, MYF6) and Myocyte enhancer factor 2 (MEF2) (MEF2A, MEF2C, MEF2D) families, as well as muscle growth inhibitors (MSTN, ACVR1, and SMAD1); KEGG pathway analysis revealed 106 and 20 genes were found in muscle growth related positive and negative regulatory signaling pathways. Notably, genes critical for protein synthesis, such as MTOR, IGF1, IGF1R, IRS1, INSR, and RPS6KA6, were implicated in these pathways. CONCLUSION This study employed an effective methodology to rigorously identify the potential genes associated with skeletal muscle development. A substantial number of SNPs and genes that potentially play roles in the divergence observed in skeletal muscle growth between the TIB and LW breeds were identified. These findings offer valuable insights into the genetic underpinnings of skeletal muscle development and present opportunities for enhancing meat production through pig breeding.
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Affiliation(s)
- Heli Xiong
- Animal Nutrition and Swine Institute, Yunnan Academy of Animal Husbandry and Veterinary Sciences, Kunming, 650224, China.
| | - Yan Zhang
- Animal Nutrition and Swine Institute, Yunnan Academy of Animal Husbandry and Veterinary Sciences, Kunming, 650224, China
| | - Zhiyong Zhao
- Animal Nutrition and Swine Institute, Yunnan Academy of Animal Husbandry and Veterinary Sciences, Kunming, 650224, China
| | - Qian Sha
- Animal Nutrition and Swine Institute, Yunnan Academy of Animal Husbandry and Veterinary Sciences, Kunming, 650224, China
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Browne IM, André F, Chandarlapaty S, Carey LA, Turner NC. Optimal targeting of PI3K-AKT and mTOR in advanced oestrogen receptor-positive breast cancer. Lancet Oncol 2024; 25:e139-e151. [PMID: 38547898 DOI: 10.1016/s1470-2045(23)00676-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 04/02/2024]
Abstract
The growing availability of targeted therapies for patients with advanced oestrogen receptor-positive breast cancer has improved survival, but there remains much to learn about the optimal management of these patients. The PI3K-AKT and mTOR pathways are among the most commonly activated pathways in breast cancer, whose crucial role in the pathogenesis of this tumour type has spurred major efforts to target this pathway at specific kinase hubs. Approvals for oestrogen receptor-positive advanced breast cancer include the PI3K inhibitor alpelisib for PIK3CA-mutated tumours, the AKT inhibitor capivasertib for tumours with alterations in PIK3CA, AKT1, or PTEN, and the mTOR inhibitor everolimus, which is used irrespective of mutation status. The availability of different inhibitors leaves physicians with a potentially challenging decision over which of these therapies should be used for individual patients and when. In this Review, we present a comprehensive summary of our current understanding of the pathways and the three inhibitors and discuss strategies for the optimal sequencing of therapies in the clinic, particularly after progression on a CDK4/6 inhibitor.
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Affiliation(s)
- Iseult M Browne
- Breast Cancer Now Research Centre, Institute of Cancer Research, London, UK; Ralph Lauren Centre for Breast Cancer Research and Breast Unit, The Royal Marsden Hospital NHS Foundation Trust, London, UK
| | - Fabrice André
- Department of Medical Oncology, INSERM U981, Institut Gustave Roussy, Université Paris Saclay, Villejuif, France
| | | | - Lisa A Carey
- University of North Carolina Lineberger Comprehensive Cancer Center, Chapel Hill, NC, USA
| | - Nicholas C Turner
- Breast Cancer Now Research Centre, Institute of Cancer Research, London, UK; Ralph Lauren Centre for Breast Cancer Research and Breast Unit, The Royal Marsden Hospital NHS Foundation Trust, London, UK.
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Cao Y, Han S, Lu H, Luo Y, Guo T, Wu Q, Luo F. Targeting mTOR Signaling by Dietary Polyphenols in Obesity Prevention. Nutrients 2022; 14:nu14235171. [PMID: 36501200 PMCID: PMC9735788 DOI: 10.3390/nu14235171] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/09/2022] Open
Abstract
Dietary polyphenols can be utilized to treat obesity and chronic disorders linked to it. Dietary polyphenols can inhibit pre-adipocyte proliferation, adipocyte differentiation, and triglyceride accumulation; meanwhile, polyphenols can also stimulate lipolysis and fatty acid β-oxidation, but the molecular mechanisms of anti-obesity are still unclear. The mechanistic target of rapamycin (mTOR) is a protein kinase that regulates cell growth, survival, metabolism, and immunity. mTOR signaling is also thought to play a key role in the development of metabolic diseases such as obesity. Recent studies showed that dietary polyphenols could target mTOR to reduce obesity. In this review, we systematically summarized the research progress of polyphenols in preventing obesity through the mTOR signaling pathway. Mechanistically, polyphenols can target multiple signaling pathways and gut microbiota to regulate the mTOR signaling pathway to exert anti-obesity effects. The main mechanisms include: modulating lipid metabolism, adipogenesis, inflammation, etc. Dietary polyphenols exerting an anti-obesity effect by targeting mTOR signaling will broaden our understanding of the anti-obesity mechanisms of polyphenols and provide valuable insights for researchers in this novel field.
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Affiliation(s)
- Yunyun Cao
- Hunan Provincial Key Laboratory of Grain-Oil Deep Process and Quality Control, Hunan Provincial Key Laboratory of Forestry Edible Resources Safety and Processing, Hunan Provincial Key Laboratory of Processed Food for Special Medical Purpose, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Shuai Han
- Hunan Provincial Key Laboratory of Grain-Oil Deep Process and Quality Control, Hunan Provincial Key Laboratory of Forestry Edible Resources Safety and Processing, Hunan Provincial Key Laboratory of Processed Food for Special Medical Purpose, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Han Lu
- Hunan Provincial Key Laboratory of Grain-Oil Deep Process and Quality Control, Hunan Provincial Key Laboratory of Forestry Edible Resources Safety and Processing, Hunan Provincial Key Laboratory of Processed Food for Special Medical Purpose, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Yi Luo
- Department of Clinic Medicine, Xiangya School of Medicine, Central South University, Changsha 410008, China
| | - Tianyi Guo
- Hunan Provincial Key Laboratory of Grain-Oil Deep Process and Quality Control, Hunan Provincial Key Laboratory of Forestry Edible Resources Safety and Processing, Hunan Provincial Key Laboratory of Processed Food for Special Medical Purpose, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Qi Wu
- Hunan Provincial Key Laboratory of Grain-Oil Deep Process and Quality Control, Hunan Provincial Key Laboratory of Forestry Edible Resources Safety and Processing, Hunan Provincial Key Laboratory of Processed Food for Special Medical Purpose, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Feijun Luo
- Hunan Provincial Key Laboratory of Grain-Oil Deep Process and Quality Control, Hunan Provincial Key Laboratory of Forestry Edible Resources Safety and Processing, Hunan Provincial Key Laboratory of Processed Food for Special Medical Purpose, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
- Correspondence:
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Zhao X, Wang S, Wang S, Xie J, Cui D. mTOR signaling: A pivotal player in Treg cell dysfunction in systemic lupus erythematosus. Clin Immunol 2022; 245:109153. [DOI: 10.1016/j.clim.2022.109153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 09/30/2022] [Accepted: 10/04/2022] [Indexed: 11/03/2022]
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Nowosad A, Besson A. Lysosomes at the Crossroads of Cell Metabolism, Cell Cycle, and Stemness. Int J Mol Sci 2022; 23:ijms23042290. [PMID: 35216401 PMCID: PMC8879101 DOI: 10.3390/ijms23042290] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/11/2022] [Accepted: 02/16/2022] [Indexed: 02/07/2023] Open
Abstract
Initially described as lytic bodies due to their degradative and recycling functions, lysosomes play a critical role in metabolic adaptation to nutrient availability. More recently, the contribution of lysosomal proteins to cell signaling has been established, and lysosomes have emerged as signaling hubs that regulate diverse cellular processes, including cell proliferation and cell fate. Deciphering these signaling pathways has revealed an extensive crosstalk between the lysosomal and cell cycle machineries that is only beginning to be understood. Recent studies also indicate that a number of lysosomal proteins are involved in the regulation of embryonic and adult stem cell fate and identity. In this review, we will focus on the role of the lysosome as a signaling platform with an emphasis on its function in integrating nutrient sensing with proliferation and cell cycle progression, as well as in stemness-related features, such as self-renewal and quiescence.
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Affiliation(s)
- Ada Nowosad
- Molecular, Cellular and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France;
- Department of Oncology, KULeuven, Laboratory for Molecular Cancer Biology, Center for Cancer Biology, VIB, 3000 Leuven, Belgium
| | - Arnaud Besson
- Molecular, Cellular and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France;
- Correspondence: ; Tel.: +33-561558486
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Muñoz-Muñoz PLA, Mares-Alejandre RE, Meléndez-López SG, Ramos-Ibarra MA. Bioinformatic Analysis of Two TOR (Target of Rapamycin)-Like Proteins Encoded by Entamoeba histolytica Revealed Structural Similarities with Functional Homologs. Genes (Basel) 2021; 12:genes12081139. [PMID: 34440318 PMCID: PMC8391992 DOI: 10.3390/genes12081139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/21/2021] [Accepted: 07/24/2021] [Indexed: 01/04/2023] Open
Abstract
The target of rapamycin (TOR), also known as FKBP-rapamycin associated protein (FRAP), is a protein kinase belonging to the PIKK (phosphatidylinositol 3-kinase (PI3K)-related kinases) family. TOR kinases are involved in several signaling pathways that control cell growth and proliferation. Entamoeba histolytica, the protozoan parasite that causes human amoebiasis, contains two genes encoding TOR-like proteins: EhFRAP and EhTOR2. To assess their potential as drug targets to control the cell proliferation of E. histolytica, we studied the structural features of EhFRAP and EhTOR2 using a biocomputational approach. The overall results confirmed that both TOR amoebic homologs share structural similarities with functional TOR kinases, and show inherent abilities to form TORC complexes and participate in protein-protein interaction networks. To our knowledge, this study represents the first in silico characterization of the structure-function relationships of EhFRAP and EhTOR2.
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Li W, Li Y, Guan Y, Du Y, Zhao M, Chen X, Zhu F, Guo C, Jia Y, Li Y, Wang X, Wang X, Shi Y, Wang Q, Li Y, Zhang L. TNFAIP8L2/TIPE2 impairs autolysosome reformation via modulating the RAC1-MTORC1 axis. Autophagy 2021; 17:1410-1425. [PMID: 32460619 PMCID: PMC8205099 DOI: 10.1080/15548627.2020.1761748] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 04/21/2020] [Accepted: 04/23/2020] [Indexed: 12/11/2022] Open
Abstract
Macroautophagy/autophagy is an evolutionarily conserved process that involves the selective degradation of cytoplasmic components within lysosomes in response to starvation. Autophagy is an ancient defense mechanism that has been closely integrated with the immune system and has multiple effects on innate and adaptive immunity. The pro-inflammatory and anti-inflammatory cytokines can activate and inhibit autophagy, respectively. TNFAIP8L2/TIPE2 (tumor necrosis factor, alpha-induced protein 8-like 2) is a newly identified immune negative regulator of innate and adaptive immunity that plays an important role in immune homeostasis. However, whether and how TNFAIP8L2 controls autophagy is still unknown. Murine TNFAIP8L2 can directly bind to and block the RAC1 GTPase activity to regulate innate immunity. RAC1 can also bind to MTOR and regulate MTORC1 cellular localization and activity. Here, we find that TNFAIP8L2 can compete with MTOR for binding to the GTP-bound state of RAC1 and negatively regulate MTORC1 activity. Interestingly, TNFAIP8L2 overexpression fails to induce autophagy flux by the suppression of the MTOR activity under glutamine and serum starvation. Instead, TNFAIP8L2 appears to impair autophagic lysosome reformation (ALR) during prolonged starvation. Finally, we demonstrate that TNFAIP8L2 overexpression leads to a defect in MTOR reactivation and disrupts autophagy flux, thereby leading to cell death. Furthermore, TNFAIP8L2 deficiency can exacerbate the inflammatory response and lung injury by controlling the MTOR activity in an LPS-induced mouse endotoxemia model. Our study reveals a novel role of TNFAIP8L2 in autophagy by regulating the RAC1-MTORC1 axis that supports its potential as a target for therapeutic treatment.Abbreviations: ALR: autophagic lysosome reformation; BafA1: bafilomycin A1; BMDMs: bone marrow-derived macrophages; Co-IP: Co-Immunoprecipitation; LAMP1: lysosomal associated membrane protein 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MTORC1: mechanistic target of rapamycin kinase complex 1; RAPA: rapamycin; RPS6: ribosomal protein S6; SQSTM1/p62: sequestosome 1; Starv: Starvation; TNFAIP8L2/TIPE2: tumor necrosis factor-alpha-induced protein-8 like-2.
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Affiliation(s)
- Wen Li
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yulan Li
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yetong Guan
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yingxin Du
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Mingsheng Zhao
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Xiaotong Chen
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Faliang Zhu
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Chun Guo
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yufeng Jia
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yuan Li
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Xiaoyu Wang
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Xiaoyan Wang
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yongyu Shi
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Qun Wang
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yan Li
- Department of Pathogen Biology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Lining Zhang
- Department of Immunology, School of Basic Medical Science, Shandong University, Jinan, China
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Abstract
This review provides epidemiological and translational evidence for milk and dairy intake as critical risk factors in the pathogenesis of hepatocellular carcinoma (HCC). Large epidemiological studies in the United States and Europe identified total dairy, milk and butter intake with the exception of yogurt as independent risk factors of HCC. Enhanced activity of mechanistic target of rapamycin complex 1 (mTORC1) is a hallmark of HCC promoted by hepatitis B virus (HBV) and hepatitis C virus (HCV). mTORC1 is also activated by milk protein-induced synthesis of hepatic insulin-like growth factor 1 (IGF-1) and branched-chain amino acids (BCAAs), abundant constituents of milk proteins. Over the last decades, annual milk protein-derived BCAA intake increased 3 to 5 times in Western countries. In synergy with HBV- and HCV-induced secretion of hepatocyte-derived exosomes enriched in microRNA-21 (miR-21) and miR-155, exosomes of pasteurized milk as well deliver these oncogenic miRs to the human liver. Thus, milk exosomes operate in a comparable fashion to HBV- or HCV- induced exosomes. Milk-derived miRs synergistically enhance IGF-1-AKT-mTORC1 signaling and promote mTORC1-dependent translation, a meaningful mechanism during the postnatal growth phase, but a long-term adverse effect promoting the development of HCC. Both, dietary BCAA abundance combined with oncogenic milk exosome exposure persistently overstimulate hepatic mTORC1. Chronic alcohol consumption as well as type 2 diabetes mellitus (T2DM), two HCC-related conditions, increase BCAA plasma levels. In HCC, mTORC1 is further hyperactivated due to RAB1 mutations as well as impaired hepatic BCAA catabolism, a metabolic hallmark of T2DM. The potential HCC-preventive effect of yogurt may be caused by lactobacilli-mediated degradation of BCAAs, inhibition of branched-chain α-ketoacid dehydrogenase kinase via production of intestinal medium-chain fatty acids as well as degradation of milk exosomes including their oncogenic miRs. A restriction of total animal protein intake realized by a vegetable-based diet is recommended for the prevention of HCC.
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Affiliation(s)
- Bodo C Melnik
- Department of Dermatology, Environmental Medicine and Health Theory, University of Osnabrück, Osnabrück, Germany
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Melnik BC. Lifetime Impact of Cow's Milk on Overactivation of mTORC1: From Fetal to Childhood Overgrowth, Acne, Diabetes, Cancers, and Neurodegeneration. Biomolecules 2021; 11:404. [PMID: 33803410 PMCID: PMC8000710 DOI: 10.3390/biom11030404] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/04/2021] [Accepted: 03/04/2021] [Indexed: 02/07/2023] Open
Abstract
The consumption of cow's milk is a part of the basic nutritional habits of Western industrialized countries. Recent epidemiological studies associate the intake of cow's milk with an increased risk of diseases, which are associated with overactivated mechanistic target of rapamycin complex 1 (mTORC1) signaling. This review presents current epidemiological and translational evidence linking milk consumption to the regulation of mTORC1, the master-switch for eukaryotic cell growth. Epidemiological studies confirm a correlation between cow's milk consumption and birthweight, body mass index, onset of menarche, linear growth during childhood, acne vulgaris, type 2 diabetes mellitus, prostate cancer, breast cancer, hepatocellular carcinoma, diffuse large B-cell lymphoma, neurodegenerative diseases, and all-cause mortality. Thus, long-term persistent consumption of cow's milk increases the risk of mTORC1-driven diseases of civilization. Milk is a highly conserved, lactation genome-controlled signaling system that functions as a maternal-neonatal relay for optimized species-specific activation of mTORC1, the nexus for regulation of eukaryotic cell growth, and control of autophagy. A deeper understanding of milk´s impact on mTORC1 signaling is of critical importance for the prevention of common diseases of civilization.
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Affiliation(s)
- Bodo C Melnik
- Department of Dermatology, Environmental Medicine and Health Theory, University of Osnabrück, Am Finkenhügel 7a, D-49076 Osnabrück, Germany
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Peroxisome Proliferator-Activated Receptors and Caloric Restriction-Common Pathways Affecting Metabolism, Health, and Longevity. Cells 2020; 9:cells9071708. [PMID: 32708786 PMCID: PMC7407644 DOI: 10.3390/cells9071708] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/14/2020] [Accepted: 07/14/2020] [Indexed: 02/06/2023] Open
Abstract
Caloric restriction (CR) is a traditional but scientifically verified approach to promoting health and increasing lifespan. CR exerts its effects through multiple molecular pathways that trigger major metabolic adaptations. It influences key nutrient and energy-sensing pathways including mammalian target of rapamycin, Sirtuin 1, AMP-activated protein kinase, and insulin signaling, ultimately resulting in reductions in basic metabolic rate, inflammation, and oxidative stress, as well as increased autophagy and mitochondrial efficiency. CR shares multiple overlapping pathways with peroxisome proliferator-activated receptors (PPARs), particularly in energy metabolism and inflammation. Consequently, several lines of evidence suggest that PPARs might be indispensable for beneficial outcomes related to CR. In this review, we present the available evidence for the interconnection between CR and PPARs, highlighting their shared pathways and analyzing their interaction. We also discuss the possible contributions of PPARs to the effects of CR on whole organism outcomes.
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Kazemi A, Speakman JR, Soltani S, Djafarian K. Effect of calorie restriction or protein intake on circulating levels of insulin like growth factor I in humans: A systematic review and meta-analysis. Clin Nutr 2020; 39:1705-1716. [DOI: 10.1016/j.clnu.2019.07.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 07/21/2019] [Accepted: 07/22/2019] [Indexed: 12/22/2022]
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Melnik BC. Milk exosomal miRNAs: potential drivers of AMPK-to-mTORC1 switching in β-cell de-differentiation of type 2 diabetes mellitus. Nutr Metab (Lond) 2019; 16:85. [PMID: 31827573 PMCID: PMC6898964 DOI: 10.1186/s12986-019-0412-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 11/22/2019] [Indexed: 12/15/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) steadily increases in prevalence since the 1950's, the period of widespread distribution of refrigerated pasteurized cow's milk. Whereas breastfeeding protects against the development of T2DM in later life, accumulating epidemiological evidence underlines the role of cow's milk consumption in T2DM. Recent studies in rodent models demonstrate that during the breastfeeding period pancreatic β-cells are metabolically immature and preferentially proliferate by activation of mechanistic target of rapamycin complex 1 (mTORC1) and suppression of AMP-activated protein kinase (AMPK). Weaning determines a metabolic switch of β-cells from a proliferating, immature phenotype with low insulin secretion to a differentiated mature phenotype with glucose-stimulated insulin secretion, less proliferation, reduced mTORC1- but increased AMPK activity. Translational evidence presented in this perspective implies for the first time that termination of milk miRNA transfer is the driver of this metabolic switch. miRNA-148a is a key inhibitor of AMPK and phosphatase and tensin homolog, crucial suppressors of mTORC1. β-Cells of diabetic patients return to the postnatal phenotype with high mTORC1 and low AMPK activity, explained by continuous transfer of bovine milk miRNAs to the human milk consumer. Bovine milk miRNA-148a apparently promotes β-cell de-differentiation to the immature mTORC1-high/AMPK-low phenotype with functional impairments in insulin secretion, increased mTORC1-driven endoplasmic reticulum stress, reduced autophagy and early β-cell apoptosis. In contrast to pasteurized cow's milk, milk's miRNAs are inactivated by bacterial fermentation, boiling and ultra-heat treatment and are missing in current infant formula. Persistent milk miRNA signaling adds a new perspective to the pathogenesis of T2DM and explains the protective role of breastfeeding but the diabetogenic effect of continued milk miRNA signaling by persistent consumption of pasteurized cow's milk.
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Affiliation(s)
- Bodo C. Melnik
- Department of Dermatology, Environmental Medicine and Health Theory, University of Osnabrück, Am Finkenhügel 7A, D-49076 Osnabrück, Germany
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15
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Inpanathan S, Botelho RJ. The Lysosome Signaling Platform: Adapting With the Times. Front Cell Dev Biol 2019; 7:113. [PMID: 31281815 PMCID: PMC6595708 DOI: 10.3389/fcell.2019.00113] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 06/05/2019] [Indexed: 12/12/2022] Open
Abstract
Lysosomes are the terminal degradative compartment of autophagy, endocytosis and phagocytosis. What once was viewed as a simple acidic organelle in charge of macromolecular digestion has emerged as a dynamic organelle capable of integrating cellular signals and producing signal outputs. In this review, we focus on the concept that the lysosome surface serves as a platform to assemble major signaling hubs like mTORC1, AMPK, GSK3 and the inflammasome. These molecular assemblies integrate and facilitate cross-talk between signals such as amino acid and energy levels, membrane damage and infection, and ultimately enable responses such as autophagy, cell growth, membrane repair and microbe clearance. In particular, we review how molecular machinery like the vacuolar-ATPase proton pump, sestrins, the GATOR complexes, and the Ragulator, modulate mTORC1, AMPK, GSK3 and inflammation. We then elaborate how these signals control autophagy initiation and resolution, TFEB-mediated lysosome adaptation, lysosome remodeling, antigen presentation, inflammation, membrane damage repair and clearance. Overall, by being at the cross-roads for several membrane pathways, lysosomes have emerged as the ideal surveillance compartment to sense, integrate and elicit cellular behavior and adaptation in response to changing environmental and cellular conditions.
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Affiliation(s)
- Subothan Inpanathan
- Department of Chemistry and Biology, Graduate Program in Molecular Science, Ryerson University, Toronto, ON, Canada
| | - Roberto J Botelho
- Department of Chemistry and Biology, Graduate Program in Molecular Science, Ryerson University, Toronto, ON, Canada
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16
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Association analysis between feed efficiency and expression of key genes of the avTOR signaling pathway in meat-type ducks. Mol Biol Rep 2019; 46:3537-3544. [PMID: 31140048 DOI: 10.1007/s11033-019-04720-y] [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: 11/21/2018] [Accepted: 02/07/2019] [Indexed: 10/26/2022]
Abstract
Genes involved in the target of rapamycin (TOR) signaling pathway are implicated in nutrient translation, cell proliferation and differentiation, and anabolism, which can affect both growth and feed intake. However, the role of TOR signaling in the regulation of feed intake and feed efficiency in poultry is not clear. In the present study, a total of 1000 ducks, of similar initial weight, were chosen and transferred to individual cages to determine their residual feed intake (RFI) from the age of 21 to 42 days. Subsequently, 60 ducks, which were divided into high (HRFI) and low (LRFI) groups according to their RFI, were chosen to analyze the TOR signaling activities in the liver. The differential expression level of genes involved in the TOR signaling pathway was assayed by the real-time polymerase chain reaction. In the liver, the expression of AKT, avTOR, avLST8, and S6K1 was significantly higher in LRFI ducks than in HRFI ducks; avTOR and AKT were negatively associated with the feed conversion ratio and RFI. Furthermore, PI3K was moderately positively associated with AKT; AKT was strongly positively associated with PI3K, avTOR, avLST8, and S6K1; and avTOR was strongly positively associated with S6K1. In conclusion, the activation of avTOR signaling in the liver of LRFI ducks might be ascribed to higher energy state or more active nutrient transport (amino acids), or both, than those in the liver of HRFI ducks. The results of the present study indicate that AKT and avTOR of TOR signaling might be used as candidate genes to assess molecular regulation of feed efficiency.
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17
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Qu L, Pan C, He SM, Lang B, Gao GD, Wang XL, Wang Y. The Ras Superfamily of Small GTPases in Non-neoplastic Cerebral Diseases. Front Mol Neurosci 2019; 12:121. [PMID: 31213978 PMCID: PMC6555388 DOI: 10.3389/fnmol.2019.00121] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 04/25/2019] [Indexed: 12/22/2022] Open
Abstract
The small GTPases from the Ras superfamily play crucial roles in basic cellular processes during practically the entire process of neurodevelopment, including neurogenesis, differentiation, gene expression, membrane and protein traffic, vesicular trafficking, and synaptic plasticity. Small GTPases are key signal transducing enzymes that link extracellular cues to the neuronal responses required for the construction of neuronal networks, as well as for synaptic function and plasticity. Different subfamilies of small GTPases have been linked to a number of non-neoplastic cerebral diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), intellectual disability, epilepsy, drug addiction, Huntington’s disease (HD), amyotrophic lateral sclerosis (ALS) and a large number of idiopathic cerebral diseases. Here, we attempted to make a clearer illustration of the relationship between Ras superfamily GTPases and non-neoplastic cerebral diseases, as well as their roles in the neural system. In future studies, potential treatments for non-neoplastic cerebral diseases which are based on small GTPase related signaling pathways should be explored further. In this paper, we review all the available literature in support of this possibility.
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Affiliation(s)
- Liang Qu
- Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University, Xi'an, China
| | - Chao Pan
- Beijing Institute of Biotechnology, Beijing, China
| | - Shi-Ming He
- Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University, Xi'an, China.,Department of Neurosurgery, Xi'an International Medical Center, Xi'an, China
| | - Bing Lang
- The School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom.,Department of Psychiatry, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Guo-Dong Gao
- Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University, Xi'an, China
| | - Xue-Lian Wang
- Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University, Xi'an, China
| | - Yuan Wang
- Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University, Xi'an, China
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18
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Li Y, Li J, Zhou Q, Liu Y, Chen W, Xu H. mTORC1 signaling is essential for neurofibromatosis type I gene modulated osteogenic differentiation of BMSCs. J Cell Biochem 2018; 120:2886-2896. [DOI: 10.1002/jcb.26626] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/19/2017] [Indexed: 12/23/2022]
Affiliation(s)
- YiQiang Li
- Department of Pediatric Orthopaedics, GuangZhou Women and Children's Medical Center, Guangzhou Medical University Guangzhou China
| | - JingChun Li
- Department of Pediatric Orthopaedics, GuangZhou Women and Children's Medical Center, Guangzhou Medical University Guangzhou China
| | - QingHe Zhou
- Department of Pediatric Orthopaedics, GuangZhou Women and Children's Medical Center, Guangzhou Medical University Guangzhou China
| | - Yuanzhong Liu
- Department of Pediatric Orthopaedics, GuangZhou Women and Children's Medical Center, Guangzhou Medical University Guangzhou China
| | - WeiDong Chen
- Department of Pediatric Orthopaedics, GuangZhou Women and Children's Medical Center, Guangzhou Medical University Guangzhou China
| | - HongWen Xu
- Department of Pediatric Orthopaedics, GuangZhou Women and Children's Medical Center, Guangzhou Medical University Guangzhou China
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19
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He L, Zhang J, Zhao J, Ma N, Kim SW, Qiao S, Ma X. Autophagy: The Last Defense against Cellular Nutritional Stress. Adv Nutr 2018; 9:493-504. [PMID: 30032222 PMCID: PMC6054220 DOI: 10.1093/advances/nmy011] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Homeostasis of nutrient metabolism is critical for maintenance of the normal physiologic status of the cell and the integral health of humans and mammals. In vivo, there is a highly efficient and precise process involved in nutrient recycling and organelle cleaning. This process is named autophagy, and it can be induced in response to the dynamic change of nutrients. When cells face nutritional stress, such as stress caused by nutrient deficiency or nutrient excess, the autophagy pathway will be activated. Generally, when nutrients are withdrawn, cells will sense the signs of starvation and respond. AMP-activated protein kinase and the mammalian target of rapamycin, two of the major metabolic kinases, are responsible for monitoring cellular energy and the concentration of amino acids, respectively. Nutrient excess also induces autophagy, mainly via the reactive oxygen species and endoplasmic reticulum stress pathway. When nutritional stress activates the autophagy pathway, the nutrients or damaged organelles will be recycled for cell survival. However, if autophagy is overwhelmingly induced, autophagic cell death will possibly occur. The balance of the autophagy induction is the crucial factor for cell survival or death. Herein, we summarize the current knowledge on the induction of autophagy, the autophagy response under nutritional stresses, and autophagic cell death and related diseases, which will highlight the process of nutritional stress-induced autophagy and its important physiologic and/or pathologic roles in cell metabolism and diseases, and shed light on the research into the mechanism and clinical applications of autophagy induced by nutritional stresses.
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Affiliation(s)
- Long He
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Center, China Agricultural University, Beijing, China
| | - Jie Zhang
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Center, China Agricultural University, Beijing, China
| | - Jinshan Zhao
- College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, China
| | - Ning Ma
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Center, China Agricultural University, Beijing, China
| | - Sung Woo Kim
- Department of Animal Science, North Carolina State University, Raleigh, NC
| | - Shiyan Qiao
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Center, China Agricultural University, Beijing, China
| | - Xi Ma
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Center, China Agricultural University, Beijing, China,College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, China,Department of Internal Medicine, Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX,Address correspondence to XM (e-mail: )
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20
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Saliba E, Evangelinos M, Gournas C, Corrillon F, Georis I, André B. The yeast H +-ATPase Pma1 promotes Rag/Gtr-dependent TORC1 activation in response to H +-coupled nutrient uptake. eLife 2018; 7:31981. [PMID: 29570051 PMCID: PMC5915174 DOI: 10.7554/elife.31981] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 03/22/2018] [Indexed: 11/25/2022] Open
Abstract
The yeast Target of Rapamycin Complex 1 (TORC1) plays a central role in controlling growth. How amino acids and other nutrients stimulate its activity via the Rag/Gtr GTPases remains poorly understood. We here report that the signal triggering Rag/Gtr-dependent TORC1 activation upon amino-acid uptake is the coupled H+ influx catalyzed by amino-acid/H+ symporters. H+-dependent uptake of other nutrients, ionophore-mediated H+ diffusion, and inhibition of the vacuolar V-ATPase also activate TORC1. As the increase in cytosolic H+ elicited by these processes stimulates the compensating H+-export activity of the plasma membrane H+-ATPase (Pma1), we have examined whether this major ATP-consuming enzyme might be involved in TORC1 control. We find that when the endogenous Pma1 is replaced with a plant H+-ATPase, H+ influx or increase fails to activate TORC1. Our results show that H+ influx coupled to nutrient uptake stimulates TORC1 activity and that Pma1 is a key actor in this mechanism. Cells adapt their growth rate depending on the amount of nutrients available. The protein complex called TORC1 plays a central role in this. When nutrients are abundant, TORC1 is very active and stimulates the production of proteins and other molecules needed for the cell to grow. However, when nutrients such as amino acids become scarce, TORC1 reduces its activity and allows the cells to adapt to starvation. This TORC1-mediated control of the metabolism is crucial for the cell to survive, and faulty TORC1 proteins have been associated with several diseases including cancers. TORC1 was originally discovered in yeast, which provides a powerful model to study this control system. However, until now, it was not known how TORC1 is reactivated when amino acids are added to cells that have been starved of these molecules. Knowing the answer to this question would allow us to better understand how the availability of nutrients controls the activity of TORC1. Now, Saliba et al. have discovered that TORC1 is not reactivated by the amino acids themselves, but by protons, which are positively charged hydrogen ions that travel into the cell together with the amino acids. This influx of protons is the driving force behind the active transport of amino acids and other nutrients into the cell, and potentially serves as a general signal to activate TORC1 in response to the uptake of nutrients, especially when cells have been starved. Furthermore, the results showed that a specific enzyme in the cell membrane plays an essential role in activating TORC1. This enzyme pumps the protons out of the cell to compensate for their influx and to maintain the proton gradient in the membrane that drives the absorption of nutrients. When this enzyme was replaced with an equivalent plant enzyme, the proton-coupled nutrient uptake did not activate TORC1 in the yeast cells. These findings may help scientists who are interested in how TORC1 is regulated in organisms other than mammals, such as plants or fungi. A next step will be to find out how exactly the proton pump in the cell membrane helps to activate TORC1.
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Affiliation(s)
- Elie Saliba
- Molecular Physiology of the Cell, Université Libre de Bruxelles, Biopark, Gosselies, Belgium
| | - Minoas Evangelinos
- Molecular Physiology of the Cell, Université Libre de Bruxelles, Biopark, Gosselies, Belgium
| | - Christos Gournas
- Molecular Physiology of the Cell, Université Libre de Bruxelles, Biopark, Gosselies, Belgium
| | - Florent Corrillon
- Molecular Physiology of the Cell, Université Libre de Bruxelles, Biopark, Gosselies, Belgium
| | - Isabelle Georis
- Institut de Recherches Microbiologiques J.-M. Wiame, Brussels, Belgium
| | - Bruno André
- Molecular Physiology of the Cell, Université Libre de Bruxelles, Biopark, Gosselies, Belgium
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21
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Choi H, Son JB, Kang J, Kwon J, Kim JH, Jung M, Kim SK, Kim S, Mun JY. Leucine-induced localization of Leucyl-tRNA synthetase in lysosome membrane. Biochem Biophys Res Commun 2017; 493:1129-1135. [PMID: 28882589 DOI: 10.1016/j.bbrc.2017.09.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 09/03/2017] [Indexed: 12/24/2022]
Abstract
Leucyl-tRNA synthetase (LRS) plays major roles in providing leucine-tRNA and activating mechanistic target of rapamycin complex 1 (mTORC1) through intracellular leucine sensing. mTORC1 activated by amino acids affects the influence on physiology functions including cell proliferation, protein synthesis and autophagy in various organisms. Biochemical results demonstrating leucine sensing have been published, but visual results are lacking. Therefore, we observed the location of LRS with and without leucine using stimulated emission depletion (STED) microscopy one of the super-resolution microscopy and transmission electron microscopy (TEM). This revealed that LRS was translocated to the lysosome on addition of leucine. The translocation was inhibited by treatment with compound BC-LI-0186, disrupting the interaction between RagD and LRS. Immuno-TEM revealed a clear decrease in LRS translocation to the lysosome on addition of the inhibitor. This direct visualization of leucine sensing and LRS translocation to the lysosome was related to mTORC1 activation. To study the relationship between mTORC1 activation and LRS translocation, we monitored the change in autophagy for each condition using TEM and CLSM. The results showed a decrease in autophagy on addition of leucine, demonstrating crosstalk between leucine sensing, LRS translocation, RagD interaction, and mTORC1 activation.
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Affiliation(s)
- Hyosun Choi
- BK21 Plus Program, Department of Senior Healthcare, Graduate School, Eulji University, South Korea
| | - Jung Bae Son
- Department of Chemistry, Seoul National University, South Korea
| | - Jooyoun Kang
- Department of Chemistry, Seoul National University, South Korea
| | - Jiwoong Kwon
- Department of Biophysics and Chemical Biology, Seoul National University, South Korea; Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, South Korea
| | - Jong Hyun Kim
- Medicinal Bioconvergence Research Center, Seoul National University, South Korea
| | - Minkyo Jung
- Department of Convergence Medicine, University of Ulsan College of Medicine and Asan Institute for Life Sciences, Asan Medical Center, South Korea
| | - Seong Keun Kim
- Department of Chemistry, Seoul National University, South Korea
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, Seoul National University, South Korea; Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Technology, College of Pharmacy, Seoul National University, South Korea
| | - Ji Young Mun
- BK21 Plus Program, Department of Senior Healthcare, Graduate School, Eulji University, South Korea; Department of Biomedical Laboratory Science, College of Health Sciences, Eulji University, South Korea.
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22
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Hare SH, Harvey AJ. mTOR function and therapeutic targeting in breast cancer. Am J Cancer Res 2017; 7:383-404. [PMID: 28400999 PMCID: PMC5385631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 12/05/2016] [Indexed: 06/07/2023] Open
Abstract
The mTOR pathway was discovered in the late 1970s after the compound and natural inhibitor of mTOR, rapamycin was isolated from the bacterium Streptomyces hygroscopicus. mTOR is serine/threonine kinase belonging to the phosphoinositide 3-kinase related kinase (PIKK) family. It forms two distinct complexes; mTORC1 and mTORC2. mTORC1 has a key role in regulating protein synthesis and autophagy whilst mTORC2 is involved in regulating kinases of the AGC family. mTOR signaling is often over active in multiple cancer types including breast cancer. This can involve mutations in mTOR itself but more commonly, in breast cancer, this is related to an increase in activity of ErbB family receptors or alterations and mutations of PI3K signaling. Rapamycin and its analogues (rapalogues) bind to the intercellular receptor FKBP12, and then predominantly inhibit mTORC1 signaling via an allosteric mechanism. Research has shown that inhibition of mTOR is a useful strategy in tackling cancers, with it acting to slow tumor growth and limit the spread of a cancer. Rapalogues have now made their way into the clinic with the rapalogue everolimus (RAD-001/Afinitor) approved for use in conjunction with exemestane, in post-menopausal breast cancer patients with advanced disease who are HER-2 negative (normal expression), hormone receptor positive and whose prior treatment with non-steroidal aromatase inhibitors has failed. Testing across multiple trials has proven that everolimus and other rapalogues are a viable way of treating certain types of cancer. However, rapalogues have shown some drawbacks both in research and clinically, with their use often activating feedback pathways that counter their usefulness. As such, new types of inhibitors are being explored that work via different mechanisms, including inhibitors that are ATP competitive with mTOR and which act to perturb signaling from both mTOR complexes.
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Affiliation(s)
- Stephen H Hare
- Institute for Environment Health and Societies, Brunel University London Uxbridge, UB8 3PH, United Kingdom
| | - Amanda J Harvey
- Institute for Environment Health and Societies, Brunel University London Uxbridge, UB8 3PH, United Kingdom
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23
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Kissing S, Rudnik S, Damme M, Lüllmann-Rauch R, Ichihara A, Kornak U, Eskelinen EL, Jabs S, Heeren J, De Brabander JK, Haas A, Saftig P. Disruption of the vacuolar-type H +-ATPase complex in liver causes MTORC1-independent accumulation of autophagic vacuoles and lysosomes. Autophagy 2017; 13:670-685. [PMID: 28129027 DOI: 10.1080/15548627.2017.1280216] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The vacuolar-type H+-translocating ATPase (v-H+-ATPase) has been implicated in the amino acid-dependent activation of the mechanistic target of rapamycin complex 1 (MTORC1), an important regulator of macroautophagy. To reveal the mechanistic links between the v-H+-ATPase and MTORC1, we destablilized v-H+-ATPase complexes in mouse liver cells by induced deletion of the essential chaperone ATP6AP2. ATP6AP2-mutants are characterized by massive accumulation of endocytic and autophagic vacuoles in hepatocytes. This cellular phenotype was not caused by a block in endocytic maturation or an impaired acidification. However, the degradation of LC3-II in the knockout hepatocytes appeared to be reduced. When v-H+-ATPase levels were decreased, we observed lysosome association of MTOR and normal signaling of MTORC1 despite an increase in autophagic marker proteins. To better understand why MTORC1 can be active when v-H+-ATPase is depleted, the activation of MTORC1 was analyzed in ATP6AP2-deficient fibroblasts. In these cells, very little amino acid-elicited activation of MTORC1 was observed. In contrast, insulin did induce MTORC1 activation, which still required intracellular amino acid stores. These results suggest that in vivo the regulation of macroautophagy depends not only on v-H+-ATPase-mediated regulation of MTORC1.
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Affiliation(s)
- Sandra Kissing
- a Institut für Biochemie, Christian-Albrechts-Universität zu Kiel , Germany
| | - Sönke Rudnik
- a Institut für Biochemie, Christian-Albrechts-Universität zu Kiel , Germany
| | - Markus Damme
- a Institut für Biochemie, Christian-Albrechts-Universität zu Kiel , Germany
| | | | - Atsuhiro Ichihara
- c Department of Medicine II , Tokyo Women´s Medical University , Japan
| | - Uwe Kornak
- d Institut für Medizinische Genetik und Humangenetik, Charité-Universitaetsmedizin , Berlin , Germany
| | - Eeva-Liisa Eskelinen
- e Department of Biosciences , Division of Biochemistry and Biotechnology, University of Helsinki , Finland
| | - Sabrina Jabs
- f Leibniz-Institut für Molekulare Pharmakologie (FMP) and Max-Delbrück-Centrum für Molekulare Medizin (MDC) , Berlin , Germany
| | - Jörg Heeren
- g Institut für Biochemie und Molekulare Zellbiologie, Zentrum für Experimentelle Medizin, Universitätsklinikum Hamburg-Eppendorf , Germany
| | - Jef K De Brabander
- h Department of Biochemistry , University of Texas Southwestern Medical Center , Dallas , TX , USA
| | - Albert Haas
- i Institut für Zellbiologie, Friedrich-Wilhelms Universität Bonn , Germany
| | - Paul Saftig
- a Institut für Biochemie, Christian-Albrechts-Universität zu Kiel , Germany
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24
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Bouska A, Zhang W, Gong Q, Iqbal J, Scuto A, Vose J, Ludvigsen M, Fu K, Weisenburger DD, Greiner TC, Gascoyne RD, Rosenwald A, Ott G, Campo E, Rimsza LM, Delabie J, Jaffe ES, Braziel RM, Connors JM, Wu CI, Staudt LM, D'Amore F, McKeithan TW, Chan WC. Combined copy number and mutation analysis identifies oncogenic pathways associated with transformation of follicular lymphoma. Leukemia 2017; 31:83-91. [PMID: 27389057 PMCID: PMC5214175 DOI: 10.1038/leu.2016.175] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 05/25/2016] [Accepted: 05/27/2016] [Indexed: 12/31/2022]
Abstract
Follicular lymphoma (FL) is typically an indolent disease, but 30-40% of FL cases transform into an aggressive lymphoma (tFL) with a poor prognosis. To identify the genetic changes that drive this transformation, we sequenced the exomes of 12 cases with paired FL and tFL biopsies and identified 45 recurrently mutated genes in the FL-tFL data set and 39 in the tFL cases. We selected 496 genes of potential importance in transformation and sequenced them in 23 additional tFL cases. Integration of the mutation data with copy-number abnormality (CNA) data provided complementary information. We found recurrent mutations of miR-142, which has not been previously been reported to be mutated in FL/tFL. The genes most frequently mutated in tFL included KMT2D (MLL2), CREBBP, EZH2, BCL2 and MEF2B. Many recurrently mutated genes are involved in epigenetic regulation, the Janus-activated kinase-signal transducer and activator of transcription (STAT) or the nuclear factor-κB pathways, immune surveillance and cell cycle regulation or are TFs involved in B-cell development. Of particular interest are mutations and CNAs affecting S1P-activated pathways through S1PR1 or S1PR2, which likely regulate lymphoma cell migration and survival outside of follicles. Our custom gene enrichment panel provides high depth of coverage for the study of clonal evolution or divergence.
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Affiliation(s)
- Alyssa Bouska
- Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE
| | - Weiwei Zhang
- Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE
| | - Qiang Gong
- Department of Pathology, City of Hope National Medical Center, Duarte, CA
| | - Javeed Iqbal
- Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE
| | - Anna Scuto
- Department of Pathology, City of Hope National Medical Center, Duarte, CA
| | - Julie Vose
- Division of Hematology and Oncology, University of Nebraska Medical Center, Omaha, NE
| | | | - Kai Fu
- Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE
| | | | - Timothy C. Greiner
- Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE
| | - Randy D. Gascoyne
- Center for Lymphoid Cancer, British Columbia Cancer Agency, Vancouver, BC, Canada
| | - Andreas Rosenwald
- Institute of Pathology, University of Würzburg, and Comprehensive Cancer Center Mainfranken, Würzburg, Germany
| | - German Ott
- Department of Clinical Pathology, Robert-Bosch-Krankenhaus, and Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
| | - Elias Campo
- Hematopathology Unit, Hospital Clinic, IDIBAPS, University of Barcelona, Barcelona, Spain
| | - Lisa M. Rimsza
- Department of Pathology, University of Arizona, Tucson, AZ
| | - Jan Delabie
- Department of Pathology, University of Toronto, Toronto, Canada
| | - Elaine S. Jaffe
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, MD
| | | | - Joseph M. Connors
- Division of Medical Oncology, British Columbia Cancer Agency, Vancouver, BC, Canada
| | - Chung-I Wu
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, P.R. China
- Department of Ecology and Evolution, University of Chicago, Chicago, IL, 60637, USA
| | - Louis M. Staudt
- Metabolism Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD
| | | | | | - Wing C. Chan
- Department of Pathology, City of Hope National Medical Center, Duarte, CA
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Close GL, Hamilton DL, Philp A, Burke LM, Morton JP. New strategies in sport nutrition to increase exercise performance. Free Radic Biol Med 2016; 98:144-158. [PMID: 26855422 DOI: 10.1016/j.freeradbiomed.2016.01.016] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/19/2016] [Accepted: 01/21/2016] [Indexed: 02/03/2023]
Abstract
Despite over 50 years of research, the field of sports nutrition continues to grow at a rapid rate. Whilst the traditional research focus was one that centred on strategies to maximise competition performance, emerging data in the last decade has demonstrated how both macronutrient and micronutrient availability can play a prominent role in regulating those cell signalling pathways that modulate skeletal muscle adaptations to endurance and resistance training. Nonetheless, in the context of exercise performance, it is clear that carbohydrate (but not fat) still remains king and that carefully chosen ergogenic aids (e.g. caffeine, creatine, sodium bicarbonate, beta-alanine, nitrates) can all promote performance in the correct exercise setting. In relation to exercise training, however, it is now thought that strategic periods of reduced carbohydrate and elevated dietary protein intake may enhance training adaptations whereas high carbohydrate availability and antioxidant supplementation may actually attenuate training adaptation. Emerging evidence also suggests that vitamin D may play a regulatory role in muscle regeneration and subsequent hypertrophy following damaging forms of exercise. Finally, novel compounds (albeit largely examined in rodent models) such as epicatechins, nicotinamide riboside, resveratrol, β-hydroxy β-methylbutyrate, phosphatidic acid and ursolic acid may also promote or attenuate skeletal muscle adaptations to endurance and strength training. When taken together, it is clear that sports nutrition is very much at the heart of the Olympic motto, Citius, Altius, Fortius (faster, higher, stronger).
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Affiliation(s)
- G L Close
- Research Institute for Sport and Exercise Science (RISES), Liverpool John Moores University, Tom Reilly Building, Byrom Street, Liverpool L3 3AF, United Kingdom.
| | - D L Hamilton
- Health and Exercise Sciences Research Group, University of Stirling, Stirling, United Kingdom
| | - A Philp
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - L M Burke
- Sports Nutrition, Australian Institute of Sport, Canberra, ACT, Australia; Mary Mackillop Institute for Health Research, Melbourne, Australia
| | - J P Morton
- Research Institute for Sport and Exercise Science (RISES), Liverpool John Moores University, Tom Reilly Building, Byrom Street, Liverpool L3 3AF, United Kingdom
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Pinto-Leite R, Arantes-Rodrigues R, Sousa N, Oliveira PA, Santos L. mTOR inhibitors in urinary bladder cancer. Tumour Biol 2016; 37:11541-11551. [PMID: 27235118 DOI: 10.1007/s13277-016-5083-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 05/15/2016] [Indexed: 02/07/2023] Open
Abstract
Despite the great scientific advances that have been made in cancer treatment, there is still much to do, particularly with regard to urinary bladder cancer. Some of the drugs used in urinary bladder cancer treatment have been in use for more than 30 years and show reduced effectiveness and high recurrence rates. There have been several attempts to find new and more effective drugs, to be used alone or in combination with the drugs already in use, in order to overcome this situation.The biologically important mammalian target of rapamycin (mTOR) pathway is altered in cancer and mTOR inhibitors have raised many expectations as potentially important anticancer drugs. In this article, the authors will review the mTOR pathway and present their experiences of the use of some mTOR inhibitors, sirolimus, everolimus and temsirolimus, in isolation and in conjunction with non-mTOR inhibitors cisplatin and gemcitabine, on urinary bladder tumour cell lines. The non-muscle-invasive cell line, 5637, is the only one that exhibits a small alteration in the mTOR and AKT phosphorylation after rapalogs exposure. Also, there was a small inhibition of cell proliferation. With gemcitabine plus everolimus or temsirolimus, the results were encouraging as a more effective response was noticed with both combinations, especially in the 5637 and T24 cell lines. Cisplatin associated with everolimus or temsirolimus also gave promising results, as an antiproliferative effect was observed when the drugs were associated, in particular on the 5637 and HT1376 cell lines. Everolimus or temsirolimus in conjunction with gemcitabine or cisplatin could have an important role to play in urinary bladder cancer treatment, depending on the tumour grading.
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Affiliation(s)
- R Pinto-Leite
- Genetic Service, Cytogenetic Laboratory, Hospital Center of Trás-os-Montes and Alto Douro, Vila Real, Portugal. .,Experimental Pathology and Therapeutics Group, Portuguese Institute of Oncology, Porto, Portugal.
| | - R Arantes-Rodrigues
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.,QOPNA, Mass Spectrometry Center, Department of Chemistry, University of Aveiro, Aveiro, Portugal.,Institute for Research and Innovation in Health (I3S), Porto, Portugal
| | - Nuno Sousa
- Health School, University Fernando Pessoa, Porto, Portugal
| | - P A Oliveira
- Experimental Pathology and Therapeutics Group, Portuguese Institute of Oncology, Porto, Portugal
| | - L Santos
- Experimental Pathology and Therapeutics Group, Portuguese Institute of Oncology, Porto, Portugal.,Health School, University Fernando Pessoa, Porto, Portugal.,Medical Oncology Department, Portuguese Institute of Oncology, Porto, Portugal
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Liebl MP, Hoppe T. It's all about talking: two-way communication between proteasomal and lysosomal degradation pathways via ubiquitin. Am J Physiol Cell Physiol 2016; 311:C166-78. [PMID: 27225656 DOI: 10.1152/ajpcell.00074.2016] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Selective degradation of proteins requires a fine-tuned coordination of the two major proteolytic pathways, the ubiquitin-proteasome system (UPS) and autophagy. Substrate selection and proteolytic activity are defined by a plethora of regulatory cofactors influencing each other. Both proteolytic pathways are initiated by ubiquitylation to mark substrate proteins for degradation, although the size and/or topology of the modification are different. In this context E3 ubiquitin ligases, ensuring the covalent attachment of activated ubiquitin to the substrate, are of special importance. The regulation of E3 ligase activity, competition between different E3 ligases for binding E2 conjugation enzymes and substrates, as well as their interplay with deubiquitylating enzymes (DUBs) represent key events in the cross talk between the UPS and autophagy. The coordination between both degradation routes is further influenced by heat shock factors and ubiquitin-binding proteins (UBPs) such as p97, p62, or optineurin. Mutations in enzymes and ubiquitin-binding proteins or a general decline of both proteolytic systems during aging result in accumulation of damaged and aggregated proteins. Thus further mechanistic understanding of how UPS and autophagy communicate might allow therapeutic intervention especially against age-related diseases.
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Affiliation(s)
- Martina P Liebl
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Thorsten Hoppe
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
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28
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New insight on obesity and adipose-derived stem cells using comprehensive metabolomics. Biochem J 2016; 473:2187-203. [PMID: 27208167 DOI: 10.1042/bcj20160241] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 05/19/2016] [Indexed: 12/11/2022]
Abstract
Obesity affects the functional capability of adipose-derived stem cells (ASCs) and their effective use in regenerative medicine through mechanisms that are still poorly understood. In the present study we used a multiplatform [LC/MS, GC/MS and capillary electrophoresis/MS (CE/MS)], metabolomics, untargeted approach to investigate the metabolic alteration underlying the inequalities observed in obesity-derived ASCs. The metabolic fingerprint (metabolites within the cells) and footprint (metabolites secreted in the culture medium), from obesity- and non-obesity-derived ASCs of humans or mice, were characterized to provide valuable information. Metabolites associated with glycolysis, the tricarboxylic acid cycle, the pentose phosphate pathway and the polyol pathway were increased in the footprint of obesity-derived human ASCs, indicating alterations in carbohydrate metabolism, whereas, from the murine model, deep differences in lipid and amino acid catabolism were highlighted. Therefore, new insights on the ASCs' metabolome were provided that enhance our understanding of the processes underlying ASCs' stemness capacity and its relationship with obesity, in different cell models.
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Stabilization of p21 by mTORC1/4E-BP1 predicts clinical outcome of head and neck cancers. Nat Commun 2016; 7:10438. [PMID: 26832959 PMCID: PMC4740818 DOI: 10.1038/ncomms10438] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 12/10/2015] [Indexed: 12/30/2022] Open
Abstract
The levels, regulation and prognostic value of p21 in head and neck squamous cell carcinomas (HNSCC) has been puzzling for years. Here, we report a new mechanism of regulation of p21 by the mTORC1/4E-BP1 pathway. We find that non-phosphorylated 4E-BP1 interacts with p21 and induces its degradation. Accordingly, hyper-activation of mTORC1 results in phosphorylation of 4E-BP1 and stabilization of p21. In HNSCC, p21 levels strongly correlate with mTORC1 activity but not with p53 status. Finally, clinical data indicate that HNSCC patients with p21 and phospho-S6-double-positive tumours present a better disease-specific survival. We conclude that over-activation of the mTORC1/4E-BP1/p21 pathway is a frequent and clinically relevant alteration in HNSCC. The molecular pathways involving p21 and mTORC1 are frequently deregulated in head and neck squamous cell carcinomas (HNSCC). Here, Llanos et al. report a mechanism that regulates p21 stability through the mTORC1/4E-BP1 pathway independently of p53, and show that the mechanism is prevalent in HNSCC.
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Ma Y, Ma N, Liu Q, Qi Y, Manabe RI, Furuyashiki T. Tor Signaling Regulates Transcription of Amino Acid Permeases through a GATA Transcription Factor Gaf1 in Fission Yeast. PLoS One 2015; 10:e0144677. [PMID: 26689777 PMCID: PMC4686964 DOI: 10.1371/journal.pone.0144677] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 11/20/2015] [Indexed: 01/17/2023] Open
Abstract
In the fission yeast, two Tor isoforms, Tor1 and Tor2, oppositely regulate gene expression of amino acid permeases. To elucidate the transcriptional machinery for these regulations, here we have employed the cap analysis of gene expression (CAGE), a method of analyzing expression profiles and identifying transcriptional start sites (TSSs). The loss of Tor1 decreased, and Tor2 inhibition by its temperature sensitive mutation increased, mRNA expression of isp5+, per1+, put4+ and SPBPB2B2.01. In contrast, the loss of Tor1 increased, and Tor2 inhibition decreased, the expression of cat1+. These changes were confirmed by semi-quantitative RT-PCR. These opposite effects by the loss of Tor1 and Tor2 inhibition appeared to occur evenly across multiple TSSs for the respective genes. The motif discovery analysis based on the CAGE results identified the GATA motifs as a potential cis-regulatory element for Tor-mediated regulation. In the luciferase reporter assay, the loss of Tor1 reduced, and Tor2 inhibition and nitrogen depletion increased, the activity of isp5+ promoter as well as that of a GATAAG reporter. One of the GATAAG motifs in isp5+ promoter was critical for its transcriptional activity, and a GATA transcription factor Gaf1 was critical for the activities of isp5+ promoter and the GATAAG reporter. Furthermore, Tor2 inhibition and nitrogen depletion induced nuclear localization of Gaf1 from the cytosol and its dephosphorylation. These results suggest that Tor2 inhibition, which is known to be induced by nitrogen depletion, promotes nuclear localization of Gaf1, thereby inducing isp5+ transcription through Gaf1 binding to the GATAAG motif in its promoter. Since Gaf1 was also critical for transcription of per1+ and put4+, Tor-Gaf1 signaling may coordinate transcription of multiple amino acid permeases according to nutrient availability.
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Affiliation(s)
- Yan Ma
- Division of Pharmacology, Kobe University Graduate School of Medicine, Kobe, Japan
- * E-mail:
| | - Ning Ma
- Division of Pharmacology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Qingbin Liu
- Division of Pharmacology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yao Qi
- Division of Pharmacology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Ri-ichiroh Manabe
- Division of Genomic Technologies, RIKEN Center for Life Science Technologies, Yokohama, Japan
| | - Tomoyuki Furuyashiki
- Division of Pharmacology, Kobe University Graduate School of Medicine, Kobe, Japan
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Zhang Z, Zhang G, Kong C, Gong D. PP242 suppresses bladder cancer cell proliferation and migration through deactivating the mammalian target of rapamycin complex 2/AKT1 signaling pathway. Mol Med Rep 2015; 13:333-8. [PMID: 26548560 DOI: 10.3892/mmr.2015.4528] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Accepted: 10/06/2015] [Indexed: 11/06/2022] Open
Abstract
While most cancer types are resistant to mammalian target of rapamycin complex 1 (mTORC1) inhibitor rapamycin, recent studies have identified mTORC2 as an important prospective therapeutic target for cancer. The present study assessed the effects of mTORC2 inhibitor PP242 on the proliferation and migration of bladder cancer cells by using Cell Counting Kit‑8, 5‑ethynyl‑2'‑deoxyuridine incorporation, wound healing and Transwell assays. Furthermore, the phosphorylation status of downstream signaling proteins of mTORC1 and mTORC2 was assessed using western blot analysis. The results demonstrated that PP242 concentration‑dependently inhibited the proliferation of bladder cancer cells. Simultaneously, the migration ability of bladder cancer cells was suppressed by PP242. In addition, PP242 markedly restrained the phosphorylation of AKT1 and mTORC2, while the phosphorylation status of S6K1 and mTORC1 was not affected. These results suggested that PP242 exerts potent inhibitory effects on bladder cancer cells by modulating the activity of the mTORC2/AKT1 pathway.
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Affiliation(s)
- Zhe Zhang
- Department of Urology, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Guojun Zhang
- Department of Hematology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110022, P.R. China
| | - Chuize Kong
- Department of Urology, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Daxin Gong
- Department of Urology, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
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Abstract
PURPOSE OF REVIEW Metabolic diseases, such as type 2 diabetes, cardiac dysfunction, hypertension, and hepatic steatosis, share one critical causative factor: abnormal lipid partitioning, that redistribution of triglycerides from adipocytes to nonadipose peripheral tissues. Lipid overload of these tissues causes a number of pathological effects collectively known as lipotoxicity. If we find the way to correct lipid partitioning, we will restrain metabolic diseases, improve life quality and life expectancy and radically reduce healthcare costs. RECENT FINDINGS Lipid partitioning in the body is maintained by tightly regulated and balanced rates of de novo lipogenesis, lipolysis, adipogenesis, and mitochondrial oxidation primarily in fat and liver. Recent studies highlighted in this review have established mTOR as a central regulator of lipid storage and metabolism. SUMMARY Increased activity of mTOR in obesity may compensate for the negative consequences of overnutrition, whereas dysregulation of mTOR may lead to abnormal lipid partitioning and metabolic disease.
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Affiliation(s)
- Partha Chakrabarti
- aDivision of Cell Biology and Physiology, CSIR-Indian Institute of Chemical Biology, Kolkata, India bDepartment of Biochemistry, Boston University School of Medicine, Boston, Massachusetts, USA
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33
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Columbus DA, Steinhoff-Wagner J, Suryawan A, Nguyen HV, Hernandez-Garcia A, Fiorotto ML, Davis TA. Impact of prolonged leucine supplementation on protein synthesis and lean growth in neonatal pigs. Am J Physiol Endocrinol Metab 2015; 309:E601-10. [PMID: 26374843 PMCID: PMC4572453 DOI: 10.1152/ajpendo.00089.2015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 07/28/2015] [Indexed: 11/22/2022]
Abstract
Most low-birth weight infants experience extrauterine growth failure due to reduced nutrient intake as a result of feeding intolerance. The objective of this study was to determine whether prolonged enteral leucine supplementation improves lean growth in neonatal pigs fed a restricted protein diet. Neonatal pigs (n = 14-16/diet, 5 days old, 1.8 ± 0.3 kg) were fed by gastric catheter a whey-based milk replacement diet with either a high protein (HP) or restricted protein (RP) content or RP supplemented with leucine to the same level as in the HP diet (RPL). Pigs were fed 40 ml·kg body wt(-1)·meal(-1) every 4 h for 21 days. Feeding the HP diet resulted in greater total body weight and lean body mass compared with RP-fed pigs (P < 0.05). Masses of the longissimus dorsi muscle, heart, and kidneys were greater in the HP- than RP-fed pigs (P < 0.05). Body weight, lean body mass, and masses of the longissimus dorsi, heart, and kidneys in pigs fed the RPL diet were intermediate to RP- and HP-fed pigs. Protein synthesis and mTOR signaling were increased in all muscles with feeding (P < 0.05); leucine supplementation increased mTOR signaling and protein synthesis rate in the longissimus dorsi (P < 0.05). There was no effect of diet on indices of protein degradation signaling in any tissue (P > 0.05). Thus, when protein intake is chronically restricted, the capacity for leucine supplementation to enhance muscle protein accretion in neonatal pigs that are meal-fed milk protein-based diets is limited.
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Affiliation(s)
- Daniel A Columbus
- United States Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Julia Steinhoff-Wagner
- United States Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Agus Suryawan
- United States Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Hanh V Nguyen
- United States Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Adriana Hernandez-Garcia
- United States Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Marta L Fiorotto
- United States Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Teresa A Davis
- United States Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
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Szewczyk B, Pochwat B, Rafało A, Palucha-Poniewiera A, Domin H, Nowak G. Activation of mTOR dependent signaling pathway is a necessary mechanism of antidepressant-like activity of zinc. Neuropharmacology 2015; 99:517-26. [PMID: 26297535 DOI: 10.1016/j.neuropharm.2015.08.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 07/23/2015] [Accepted: 08/16/2015] [Indexed: 12/13/2022]
Abstract
The rapid antidepressant response to the N-methyl-D-aspartate (NMDA) receptor antagonists is mediated by activation of the mammalian target of the rapamycin (mTOR) signaling pathway, an increase in the synthesis of synaptic proteins and formation of new synapses in the prefrontal cortex (PFC) of rats. Zinc (Zn), which is a potent NMDA receptor antagonist, exerts antidepressant-like effects in screening tests and models of depression. We focused these studies in investigating whether activation of the mTOR signaling pathway is also a necessary mechanism of the antidepressant-like activity of Zn. We observed that a single injection of Zn (5 mg/kg) induced an increase in the phosphorylation of mTOR and p70S6K 30 min and 3 h after Zn treatment at time points when Zn produced also an antidepressant-like effect in the forced swim test (FST). Furthermore, Zn administered 3 h before the decapitation increased the level of brain derived neurotrophic factor (BDNF), GluA1 and synapsin I. An elevated level of GluA1 and synapsin I was still observed 24 h after the Zn treatment, although Zn did not produce any effects in the FST at that time point. We also observed that pretreatment with rapamycin (mTORC1 inhibitor), LY294002 (PI3K inhibitor), H-89 (PKA inhibitor) and GF109203X (PKC inhibitor) blocked the antidepressant-like effect of Zn in FST in rats and blocks Zn-induced activation of mTOR signaling proteins (analyzed 30 min after Zn administration). These studies indicated that the antidepressant-like activity of Zn depends on the activation of mTOR signaling and other signaling pathways related to neuroplasticity, which can indirectly modulate mTOR function.
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Affiliation(s)
- Bernadeta Szewczyk
- Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
| | - Bartłomiej Pochwat
- Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland
| | - Anna Rafało
- Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland
| | - Agnieszka Palucha-Poniewiera
- Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland
| | - Helena Domin
- Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland
| | - Gabriel Nowak
- Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland; Department of Pharmacobiology, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland
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Bommer UA, Iadevaia V, Chen J, Knoch B, Engel M, Proud CG. Growth-factor dependent expression of the translationally controlled tumour protein TCTP is regulated through the PI3-K/Akt/mTORC1 signalling pathway. Cell Signal 2015; 27:1557-68. [PMID: 25936523 DOI: 10.1016/j.cellsig.2015.04.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 04/21/2015] [Accepted: 04/25/2015] [Indexed: 11/21/2022]
Abstract
Translationally controlled tumour protein TCTP (gene symbol: TPT1) is a highly-conserved, cyto-protective protein implicated in many physiological and disease processes, in particular cancer, where it is associated with poor patient outcomes. To understand the mechanisms underlying the accumulation of high TCTP levels in cancer cells, we studied the signalling pathways that control translation of TCTP mRNA, which contains a 5'-terminal oligopyrimidine tract (5'-TOP). In HT29 colon cancer cells and in HeLa cells, serum increases the expression of TCTP two- and four-fold, respectively, and this is inhibited by rapamycin or mTOR kinase inhibitors. Polysome profiling and mRNA quantification indicate that these effects occur at the level of mRNA translation. Blocking this pathway upstream of mTOR complex 1 (mTORC1) by inhibiting Akt also prevented increases in TCTP levels in both HeLa and HT29 colon cancer cells, whereas knockout of TSC2, a negative regulator of mTORC1, led to derepression of TCTP synthesis under serum starvation. Overexpression of eIF4E enhanced the polysomal association of the TCTP mRNA, although it did not protect its translation from inhibition by rapamycin. Conversely, expression of a constitutively-active mutant of the eIF4E inhibitor 4E-BP1, which is normally inactivated by mTORC1, inhibited TCTP mRNA translation in HEK293 cells. Our results demonstrate that TCTP mRNA translation is regulated by signalling through the PI3-K/Akt/mTORC1 pathway. This explains why TCTP levels are frequently increased in cancers, since mTORC1 signalling is hyperactive in ~80% of tumours.
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Affiliation(s)
- Ulrich-Axel Bommer
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong 2522 NSW, Australia; Graduate School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong 2522 NSW, Australia.
| | | | - Jiezhong Chen
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong 2522 NSW, Australia
| | - Bianca Knoch
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong 2522 NSW, Australia
| | - Martin Engel
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong 2522 NSW, Australia
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36
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Schuster AT, Homer CR, Kemp JR, Nickerson KP, Deutschman E, Kim Y, West G, Sadler T, Stylianou E, Krokowski D, Hatzoglou M, de la Motte C, Rubin BP, Fiocchi C, McDonald C, Longworth MS. Chromosome-associated protein D3 promotes bacterial clearance in human intestinal epithelial cells by repressing expression of amino acid transporters. Gastroenterology 2015; 148:1405-1416.e3. [PMID: 25701737 PMCID: PMC4446190 DOI: 10.1053/j.gastro.2015.02.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 01/28/2015] [Accepted: 02/13/2015] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Defects in colonic epithelial barrier defenses are associated with ulcerative colitis (UC). The proteins that regulate bacterial clearance in the colonic epithelium have not been completely identified. The Drosophila chromosome-associated protein D3 (dCAP-D3) regulates responses to bacterial infection. We examined whether CAP-D3 promotes bacterial clearance in human colonic epithelium. METHODS Clearance of Salmonella or adherent-invasive Escherichia coli LF82 was assessed by gentamycin protection assays in HT-29 and Caco-2 cells expressing small hairpin RNAs against CAP-D3. We used immunoblot assays to measure levels of CAP-D3 in colonic epithelial cells from patients with UC and healthy individuals (controls). RNA sequencing identified genes activated by CAP-D3. We analyzed the roles of CAP-D3 target genes in bacterial clearance using gentamycin protection and immunofluorescence assays and studies with pharmacologic inhibitors. RESULTS CAP-D3 expression was reduced in colonic epithelial cells from patients with active UC. Reduced CAP-D3 expression decreased autophagy and impaired intracellular bacterial clearance by HT-29 and Caco-2 colonic epithelial cells. Lower levels of CAP-D3 increased transcription of genes encoding SLC7A5 and SLC3A2, the products of which heterodimerize to form an amino acid transporter in HT-29 cells after bacterial infection; levels of SLC7A5-SLC3A2 were increased in tissues from patients with UC compared with controls. Reduced CAP-D3 in HT-29 cells resulted in earlier recruitment of SLC7A5 to Salmonella-containing vacuoles, increased activity of mTORC1, and increased survival of bacteria. Inhibition of SLC7A5-SLC3A2 or mTORC1 activity rescued the bacterial clearance defects of CAP-D3-deficient cells. CONCLUSIONS CAP-D3 down-regulates transcription of genes that encode amino acid transporters (SLC7A5 and SLC3A2) to promote bacterial autophagy by colon epithelial cells. Levels of CAP-D3 protein are reduced in patients with active UC; strategies to increase its levels might restore mucosal homeostasis to patients with active UC.
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Affiliation(s)
- Andrew T Schuster
- Department of Molecular Genetics, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Craig R Homer
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Jacqueline R Kemp
- Department of Molecular Genetics, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Kourtney P Nickerson
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Emily Deutschman
- Department of Molecular Genetics, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Yeojung Kim
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Gail West
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Tammy Sadler
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Eleni Stylianou
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Dawid Krokowski
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio
| | - Maria Hatzoglou
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio
| | - Carol de la Motte
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Brian P Rubin
- Department of Molecular Genetics, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
- Department of Anatomic Pathology, Taussig Cancer Institute, Cleveland, Ohio
| | - Claudio Fiocchi
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Christine McDonald
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Michelle S Longworth
- Department of Molecular Genetics, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
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Steiner JL, Lang CH. Dysregulation of skeletal muscle protein metabolism by alcohol. Am J Physiol Endocrinol Metab 2015; 308:E699-712. [PMID: 25759394 PMCID: PMC4420901 DOI: 10.1152/ajpendo.00006.2015] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 03/03/2015] [Indexed: 12/12/2022]
Abstract
Alcohol abuse, either by acute intoxication or prolonged excessive consumption, leads to pathological changes in many organs and tissues including skeletal muscle. As muscle protein serves not only a contractile function but also as a metabolic reserve for amino acids, which are used to support the energy needs of other tissues, its content is tightly regulated and dynamic. This review focuses on the etiology by which alcohol perturbs skeletal muscle protein balance and thereby over time produces muscle wasting and weakness. The preponderance of data suggest that alcohol primarily impairs global protein synthesis, under basal conditions as well as in response to several anabolic stimuli including growth factors, nutrients, and muscle contraction. This inhibitory effect of alcohol is mediated, at least in part, by a reduction in mTOR kinase activity via a mechanism that remains poorly defined but likely involves altered protein-protein interactions within mTOR complex 1. Furthermore, alcohol can exacerbate the decrement in mTOR and/or muscle protein synthesis present in other catabolic states. In contrast, alcohol-induced changes in muscle protein degradation, either global or via specific modulation of the ubiquitin-proteasome or autophagy pathways, are relatively inconsistent and may be model dependent. Herein, changes produced by acute intoxication versus chronic ingestion are contrasted in relation to skeletal muscle metabolism, and limitations as well as opportunities for future research are discussed. As the proportion of more economically developed countries ages and chronic illness becomes more prevalent, a better understanding of the etiology of biomedical consequences of alcohol use disorders is warranted.
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Affiliation(s)
- Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Pennsylvania State College of Medicine, Hershey, Pennsylvania
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Pennsylvania State College of Medicine, Hershey, Pennsylvania
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Steiner JL, Gordon BS, Lang CH. Moderate alcohol consumption does not impair overload-induced muscle hypertrophy and protein synthesis. Physiol Rep 2015; 3:3/3/e12333. [PMID: 25780086 PMCID: PMC4393167 DOI: 10.14814/phy2.12333] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Chronic alcohol consumption leads to muscle weakness and atrophy in part by suppressing protein synthesis and mTORC1-mediated signaling. However, it is unknown whether moderate alcohol consumption also prevents overload-induced muscle growth and related anabolic signaling. Hypertrophy of the plantaris muscle was induced by removal of a section of the gastrocnemius and soleus muscles from one leg of C57BL/6 adult male mice while the contralateral leg remained intact as the sham control. A nutritionally complete alcohol-containing liquid diet (EtOH) or isocaloric, alcohol-free liquid diet (Con) was provided for 14 days post-surgery. EtOH intake was increased progressively (day 1-5) before being maintained at ~20 g/day/kg BW. The plantaris muscle from the sham and OL leg was removed after 14 days at which time there was no difference in body weight between Con and EtOH-fed mice. OL increased muscle weight (90%) and protein synthesis (125%) in both Con and EtOH mice. The overload-induced increase in mTOR (Ser2448), 4E-BP1 (Thr37/46), S6K1 (Thr389), rpS6 (Ser240/244), and eEF2 (Thr56) were comparable in muscle from Con and EtOH mice. Modulation of signaling upstream of mTORC1 including REDD1 protein expression, Akt (Thr308), PRAS40 (Thr246), and ERK (Thr202/Tyr204) also did not differ between Con and EtOH mice. Markers of autophagy (ULK1, p62, and LC3) suggested inhibition of autophagy with overload and activation with alcohol feeding. These data show that moderate alcohol consumption does not impair muscle growth, and therefore imply that resistance exercise may be an effective therapeutic modality for alcoholic-related muscle disease.
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Affiliation(s)
- Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Bradley S Gordon
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
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