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Zheng X, Chu B. The biology of mitochondrial carrier homolog 2. Mitochondrion 2024; 75:101837. [PMID: 38158152 DOI: 10.1016/j.mito.2023.101837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 12/24/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
The mitochondrial carrier system is in charge of small molecule transport between the mitochondria and the cytoplasm as well as being an integral portion of the core mitochondrial function. One member of the mitochondrial carrier family of proteins, mitochondrial carrier homolog 2 (MTCH2), is characterized as a critical mitochondrial outer membrane protein insertase participating in mitochondrial homeostasis. Accumulating evidence demonstrate that MTCH2 is integrally linked to cell death and mitochondrial metabolism, and its genetic alterations cause a variety of disease phenotypes, ranging from obesity, Alzheimer's disease, and tumor. To provide a comprehensive insight into the current understanding of MTCH2, we present a detailed description of the physiopathological functions of MTCH2, ranging from apoptosis, mitochondrial dynamics, and metabolic homeostasis regulation. Moreover, we summarized the impact of MTCH2 in human diseases, and highlighted tumors, to assess the role of MTCH2 mutations or variable expression on pathogenesis and target therapeutic options.
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Affiliation(s)
- Xiaohe Zheng
- Department of Pathology, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai 317000, China
| | - Binxiang Chu
- Department of Orthopedic, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai 317000, China.
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2
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Bubak MP, Mann SN, Borowik AK, Pranay A, Batushansky A, Vieira de Sousa Neto I, Mondal SA, Doidge SM, Davidyan A, Szczygiel MM, Peelor FF, Rigsby S, Broomfield ME, Lacy CI, Rice HC, Stout MB, Miller BF. 17α-Estradiol alleviates high-fat diet-induced inflammatory and metabolic dysfunction in skeletal muscle of male and female mice. Am J Physiol Endocrinol Metab 2024; 326:E226-E244. [PMID: 38197793 PMCID: PMC11193529 DOI: 10.1152/ajpendo.00215.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 12/14/2023] [Accepted: 12/22/2023] [Indexed: 01/11/2024]
Abstract
17α-estradiol (17α-E2) is a naturally occurring nonfeminizing diastereomer of 17β-estradiol that has life span-extending effects in rodent models. To date, studies of the systemic and tissue-specific benefits of 17α-E2 have largely focused on the liver, brain, and white adipose tissue with far less focus on skeletal muscle. Skeletal muscle has an important role in metabolic and age-related disease. Therefore, this study aimed to determine whether 17α-E2 treatment has positive, tissue-specific effects on skeletal muscle during a high-fat feeding. We hypothesized that male, but not female, mice, would benefit from 17α-E2 treatment during a high-fat diet (HFD) with changes in the mitochondrial proteome to support lipid oxidation and subsequent reductions in diacylglycerol (DAG) and ceramide content. To test this hypothesis, we used a multiomics approach to determine changes in lipotoxic lipid intermediates, metabolites, and proteins related to metabolic homeostasis. Unexpectedly, we found that 17α-E2 had marked, but different, beneficial effects within each sex. In male mice, we show that 17α-E2 alleviates HFD-induced metabolic detriments of skeletal muscle by reducing the accumulation of diacylglycerol (DAG), and inflammatory cytokine levels, and altered the abundance of most of the proteins related to lipolysis and β-oxidation. Similar to male mice, 17α-E2 treatment reduced fat mass while protecting muscle mass in female mice but had little muscle inflammatory cytokine levels. Although female mice were resistant to HFD-induced changes in DAGs, 17α-E2 treatment induced the upregulation of six DAG species. In female mice, 17α-E2 treatment changed the relative abundance of proteins involved in lipolysis, β-oxidation, as well as structural and contractile proteins but to a smaller extent than male mice. These data demonstrate the metabolic benefits of 17α-E2 in skeletal muscle of male and female mice and contribute to the growing literature of the use of 17α-E2 for multi tissue health span benefits.NEW & NOTEWORTHY Using a multiomics approach, we show that 17α-E2 alleviates HFD-induced metabolic detriments in skeletal muscle by altering bioactive lipid intermediates, inflammatory cytokines, and the abundance of proteins related to lipolysis and muscle contraction. The positive effects of 17α-E2 in skeletal muscle occur in both sexes but differ in their outcome.
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Affiliation(s)
- Matthew P Bubak
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Shivani N Mann
- Department of Neuroscience, University of Arizona, Tucson, Arizona, United States
| | - Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Atul Pranay
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Albert Batushansky
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
- Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer-Sheba, Israel
| | - Ivo Vieira de Sousa Neto
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Samim A Mondal
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Stephen M Doidge
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Arik Davidyan
- Department of Biological Sciences, California State University, Sacramento, California, United States
| | - Marcelina M Szczygiel
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Sandra Rigsby
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Matle E Broomfield
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Charles I Lacy
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Geroscience and Healthy Brain Aging, Oklahoma City, Oklahoma, United States
| | - Heather C Rice
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Geroscience and Healthy Brain Aging, Oklahoma City, Oklahoma, United States
| | - Michael B Stout
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
- Oklahoma City Veterans Affairs Medical Center, Oklahoma City, Oklahoma, United States
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
- Oklahoma City Veterans Affairs Medical Center, Oklahoma City, Oklahoma, United States
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Jonsson WO, Borowik AK, Pranay A, Kinter MT, Mirek ET, Levy JL, Snyder EM, Miller BF, Anthony TG. Kinetic proteomics identifies targeted changes in liver metabolism and the ribo-interactome by dietary sulfur amino acid restriction. GeroScience 2023; 45:2425-2441. [PMID: 36976488 PMCID: PMC10651627 DOI: 10.1007/s11357-023-00758-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/19/2023] [Indexed: 03/29/2023] Open
Abstract
Dietary sulfur amino acid restriction (SAAR) protects against diet-induced obesity, extends healthspan, and coincides with an overall reduction in hepatic protein synthesis. To explore the underpinnings of SAAR-induced slowed growth and its impact on liver metabolism and proteostasis, we resolved changes in hepatic mRNA and protein abundances and compared synthesis rates of individual liver proteins. To achieve this, adult male mice were provided deuterium-labeled drinking water while freely consuming either a regular-fat or high-fat diet that was SAA restricted. Livers from these mice and their respective dietary controls were used to conduct transcriptomic, proteomic, and kinetic proteomic analyses. We found that remodeling of the transcriptome by SAAR was largely agnostic to dietary fat content. Shared signatures included activation of the integrated stress response alongside alterations in metabolic processes impacting lipids, fatty acids, and amino acids. Changes to the proteome correlated poorly with the transcriptome, and yet, functional clustering of kinetic proteomic changes in the liver during SAAR revealed that the management of fatty acids and amino acids were altered to support central metabolism and redox balance. Dietary SAAR also strongly influenced the synthesis rates of ribosomal proteins and ribosome-interacting proteins regardless of dietary fat. Taken together, dietary SAAR alters the transcriptome and proteome in the liver to safely manage increased fatty acid flux and energy use and couples this with targeted changes in the ribo-interactome to support proteostasis and slowed growth.
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Affiliation(s)
- William O Jonsson
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, 59 Dudley Road - Foran Hall, Room 166, New Brunswick, NJ, 08901, USA
| | - Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Atul Pranay
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael T Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Emily T Mirek
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, 59 Dudley Road - Foran Hall, Room 166, New Brunswick, NJ, 08901, USA
| | - Jordan L Levy
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, 59 Dudley Road - Foran Hall, Room 166, New Brunswick, NJ, 08901, USA
| | - Elizabeth M Snyder
- Department of Animal Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
- Oklahoma City VA, Oklahoma City, OK, USA
| | - Tracy G Anthony
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, 59 Dudley Road - Foran Hall, Room 166, New Brunswick, NJ, 08901, USA.
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4
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Vardar Acar N, Özgül RK. The bridge between cell survival and cell death: reactive oxygen species-mediated cellular stress. EXCLI JOURNAL 2023; 22:520-555. [PMID: 37534225 PMCID: PMC10390897 DOI: 10.17179/excli2023-6221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 06/15/2023] [Indexed: 08/04/2023]
Abstract
As a requirement of aerobic metabolism, regulation of redox homeostasis is indispensable for the continuity of living homeostasis and life. Since the stability of the redox state is necessary for the maintenance of the biological functions of the cells, the balance between the pro-oxidants, especially ROS and the antioxidant capacity is kept in balance in the cells through antioxidant defense systems. The pleiotropic transcription factor, Nrf2, is the master regulator of the antioxidant defense system. Disruption of redox homeostasis leads to oxidative and reductive stress, bringing about multiple pathophysiological conditions. Oxidative stress characterized by high ROS levels causes oxidative damage to biomolecules and cell death, while reductive stress characterized by low ROS levels disrupt physiological cell functions. The fact that ROS, which were initially attributed as harmful products of aerobic metabolism, at the same time function as signal molecules at non-toxic levels and play a role in the adaptive response called mithormesis points out that ROS have a dose-dependent effect on cell fate determination. See also Figure 1(Fig. 1).
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Affiliation(s)
- Nese Vardar Acar
- Department of Pediatric Metabolism, Institute of Child Health, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - Riza Köksal Özgül
- Department of Pediatric Metabolism, Institute of Child Health, Faculty of Medicine, Hacettepe University, Ankara, Turkey
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5
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Musci RV, Andrie KM, Walsh MA, Valenti ZJ, Linden MA, Afzali MF, Bork S, Campbell M, Johnson T, Kail TE, Martinez R, Nguyen T, Sanford J, Wist S, Murrell MD, McCord JM, Hybertson BM, Zhang Q, Javors MA, Santangelo KS, Hamilton KL. Phytochemical compound PB125 attenuates skeletal muscle mitochondrial dysfunction and impaired proteostasis in a model of musculoskeletal decline. J Physiol 2023; 601:2189-2216. [PMID: 35924591 PMCID: PMC9898472 DOI: 10.1113/jp282273] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 07/28/2022] [Indexed: 02/06/2023] Open
Abstract
Impaired mitochondrial function and disrupted proteostasis contribute to musculoskeletal dysfunction. However, few interventions simultaneously target these two drivers to prevent musculoskeletal decline. Nuclear factor erythroid 2-related factor 2 (Nrf2) activates a transcriptional programme promoting cytoprotection, metabolism, and proteostasis. We hypothesized daily treatment with a purported Nrf2 activator, PB125, in Hartley guinea pigs, a model of musculoskeletal decline, would attenuate the progression of skeletal muscle mitochondrial dysfunction and impaired proteostasis and preserve musculoskeletal function. We treated 2- and 5-month-old male and female Hartley guinea pigs for 3 and 10 months, respectively, with the phytochemical compound PB125. Longitudinal assessments of voluntary mobility were measured using Any-MazeTM open-field enclosure monitoring. Cumulative skeletal muscle protein synthesis rates were measured using deuterium oxide over the final 30 days of treatment. Mitochondrial oxygen consumption in soleus muscles was measured using high resolution respirometry. In both sexes, PB125 (1) increased electron transfer system capacity; (2) attenuated the disease/age-related decline in coupled and uncoupled mitochondrial respiration; and (3) attenuated declines in protein synthesis in the myofibrillar, mitochondrial and cytosolic subfractions of the soleus. These effects were not associated with statistically significant prolonged maintenance of voluntary mobility in guinea pigs. Collectively, treatment with PB125 contributed to maintenance of skeletal muscle mitochondrial respiration and proteostasis in a pre-clinical model of musculoskeletal decline. Further investigation is necessary to determine if these documented effects of PB125 are also accompanied by slowed progression of other aspects of musculoskeletal dysfunction. KEY POINTS: Aside from exercise, there are no effective interventions for musculoskeletal decline, which begins in the fifth decade of life and contributes to disability and cardiometabolic diseases. Targeting both mitochondrial dysfunction and impaired protein homeostasis (proteostasis), which contribute to the age and disease process, may mitigate the progressive decline in overall musculoskeletal function (e.g. gait, strength). A potential intervention to target disease drivers is to stimulate nuclear factor erythroid 2-related factor 2 (Nrf2) activation, which leads to the transcription of genes responsible for redox homeostasis, proteome maintenance and mitochondrial energetics. Here, we tested a purported phytochemical Nrf2 activator, PB125, to improve mitochondrial function and proteostasis in male and female Hartley guinea pigs, which are a model for musculoskeletal ageing. PB125 improved mitochondrial respiration and attenuated disease- and age-related declines in skeletal muscle protein synthesis, a component of proteostasis, in both male and female Hartley guinea pigs.
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Affiliation(s)
- Robert V. Musci
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Kendra M. Andrie
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Maureen A. Walsh
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Zackary J. Valenti
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Melissa A. Linden
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Maryam F. Afzali
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Sydney Bork
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Margaret Campbell
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Taylor Johnson
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Thomas E. Kail
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Richard Martinez
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Tessa Nguyen
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | - Joseph Sanford
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Sara Wist
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | | | - Joe M. McCord
- Pathways Bioscience, Aurora, CO
- Department of Medicine, Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Brooks M. Hybertson
- Pathways Bioscience, Aurora, CO
- Department of Medicine, Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Qian Zhang
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
| | | | - Kelly S. Santangelo
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Karyn L. Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
- Columbine Health Systems Center for Healthy Aging, Colorado State University, Fort Collins, CO, USA
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6
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Li P, Newhardt MF, Matsuzaki S, Eyster C, Pranay A, Peelor FF, Batushansky A, Kinter C, Subramani K, Subrahmanian S, Ahamed J, Yu P, Kinter M, Miller BF, Humphries KM. The loss of cardiac SIRT3 decreases metabolic flexibility and proteostasis in an age-dependent manner. GeroScience 2023; 45:983-999. [PMID: 36460774 PMCID: PMC9886736 DOI: 10.1007/s11357-022-00695-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 11/17/2022] [Indexed: 12/04/2022] Open
Abstract
SIRT3 is a longevity factor that acts as the primary deacetylase in mitochondria. Although ubiquitously expressed, previous global SIRT3 knockout studies have shown primarily a cardiac-specific phenotype. Here, we sought to determine how specifically knocking out SIRT3 in cardiomyocytes (SIRTcKO mice) temporally affects cardiac function and metabolism. Mice displayed an age-dependent increase in cardiac pathology, with 10-month-old mice exhibiting significant loss of systolic function, hypertrophy, and fibrosis. While mitochondrial function was maintained at 10 months, proteomics and metabolic phenotyping indicated SIRT3 hearts had increased reliance on glucose as an energy substrate. Additionally, there was a significant increase in branched-chain amino acids in SIRT3cKO hearts without concurrent increases in mTOR activity. Heavy water labeling experiments demonstrated that, by 3 months of age, there was an increase in protein synthesis that promoted hypertrophic growth with a potential loss of proteostasis in SIRT3cKO hearts. Cumulatively, these data show that the cardiomyocyte-specific loss of SIRT3 results in severe pathology with an accelerated aging phenotype.
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Affiliation(s)
- Ping Li
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
- Department of Cardiology, Central South University, The Third Xiangya Hospital, Changsha, Hunan, China
| | - Maria F Newhardt
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA.
| | - Satoshi Matsuzaki
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
| | - Craig Eyster
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
| | - Atul Pranay
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
| | - Albert Batushansky
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
- Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Caroline Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
| | - Kumar Subramani
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Sandeep Subrahmanian
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Jasimuddin Ahamed
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Pengchun Yu
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Kenneth M Humphries
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13thSt, Oklahoma City, OK, 73104, USA.
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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Jiao Y, Zhang YH, Wang CY, Yu Y, Li YZ, Cui W, Li Q, Yu YH. MicroRNA-7a-5p ameliorates diabetic peripheral neuropathy by regulating VDAC1/JNK/c-JUN pathway. Diabet Med 2023; 40:e14890. [PMID: 35616949 DOI: 10.1111/dme.14890] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 05/04/2022] [Indexed: 12/24/2022]
Abstract
AIMS The pathogenesis of diabetic peripheral neuropathy (DPN) is complex, and its treatment is extremely challenging. MicroRNA-7a-5p (miR-7a-5p) has been widely reported to alleviate apoptosis and oxidative stress in various diseases. This study aimed to investigate the mechanism of miR-7a-5p in DPN. METHODS DPN cell model was constructed with high-glucose-induced RSC96 cells. Cell apoptosis and viability were detected by flow cytometry analysis and cell counting kit-8 (CCK-8) assay respectively. The apoptosis and Jun N-terminal kinase (JNK)/c-JUN signalling pathway-related proteins expression were detected by Western blotting. The intracellular calcium content and oxidative stress levels were detected by flow cytometry and reagent kits. Mitochondrial membrane potential was evaluated by tetrechloro-tetraethylbenzimidazol carbocyanine iodide (JC-1) staining. The targeting relationship between miR-7a-5p and voltage-dependent anion-selective channel protein 1 (VDAC1) was determined by RNA pull-down assay and dual-luciferase reporter gene assay. The streptozotocin (STZ) rat model was constructed to simulate DPN in vivo. The paw withdrawal mechanical threshold (PTW) was measured by Frey capillary line, and the motor nerve conduction velocity (MNCV) was measured by electromyography. RESULTS MiR-7a-5p expression was decreased, while VDAC1 expression was increased in HG-induced RSC96 cells and STZ rats. In HG-induced RSC96 cells, miR-7a-5p overexpression promoted cell proliferation, inhibited apoptosis, down-regulated calcium release, improved mitochondrial membrane potential and repressed oxidative stress response. MiR-7a-5p negatively regulated VDAC1 expression. VDAC1 knockdown improved cell proliferation activity, suppressed cell apoptosis and mitochondrial dysfunction by inhibiting JNK/c-JUN pathway activation. MiR-7a-5p overexpression raised PTW, restored MNCV and reduced oxidative stress levels and nerve cell apoptosis in STZ rats. CONCLUSION MiR-7a-5p overexpression ameliorated mitochondrial dysfunction and inhibited apoptosis in DPN by regulating VDAC1/JNK/c-JUN pathway.
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Affiliation(s)
- Yang Jiao
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Research Institute of Anesthesiology, Tianjin, China
| | - Yue-Hua Zhang
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Research Institute of Anesthesiology, Tianjin, China
| | - Chun-Yan Wang
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Research Institute of Anesthesiology, Tianjin, China
| | - Yang Yu
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Research Institute of Anesthesiology, Tianjin, China
| | - Yi-Ze Li
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Research Institute of Anesthesiology, Tianjin, China
| | - Wei Cui
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Research Institute of Anesthesiology, Tianjin, China
| | - Qing Li
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Research Institute of Anesthesiology, Tianjin, China
| | - Yong-Hao Yu
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Research Institute of Anesthesiology, Tianjin, China
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8
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Martinez W, Zhang Q, Linden MA, Schacher N, Darvish S, Mirek ET, Levy JL, Jonsson WO, Anthony TG, Hamilton KL. Rates of protein synthesis are maintained in brain but reduced in skeletal muscle during dietary sulfur amino acid restriction. FRONTIERS IN AGING 2022; 3:975129. [PMID: 36091469 PMCID: PMC9450999 DOI: 10.3389/fragi.2022.975129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 07/11/2022] [Indexed: 11/13/2022]
Abstract
Dietary interventions such as sulfur amino acid restriction (SAAR) target multiple drivers of aging, and show promise for preventing or delaying the onset of chronic diseases. SAAR promotes metabolic health and longevity in laboratory animals. The effects of SAAR on proteostasis remain relatively unexplored. We previously reported that SAAR promotes mitochondrial proteostatic maintenance, despite suppression of global protein synthesis, in two peripheral tissues, the liver and skeletal muscle. However, the brain, a tissue vulnerable to age-related neurodegenerative diseases due to the loss of proteostasis, has not been thoroughly studied. Therefore, we sought to reveal proteostatic responses in the brains of mice fed SAAR for 35 days. Here, we demonstrate that male C57Bl/6J mice fed two levels of SAAR maintained rates of protein synthesis in all sub-cellular fractions of the pre-frontal cortex. In comparison, rates of skeletal muscle protein synthesis in SAAR fed mice were slower than control-fed mice. To gain mechanistic insight, we examined several key nutrient/energy sensitive signaling proteins: AMP-activated protein kinase (AMPK), eukaryotic initiation factor 2 (eIF2), and ribosomal protein S6 (rpS6). SAAR had minimal to modest effects on the total abundance and phosphorylation of these proteins in both tissues. Our results indicate that the pre-frontal cortex in brain is resistant to perturbations in protein synthesis in mice fed SAAR, unlike skeletal muscle, which had a reduction in global protein synthesis. The results from this study demonstrate that proteostatic control in brain is of higher priority than skeletal muscle during dietary SAAR.
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Affiliation(s)
- Wenceslao Martinez
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
| | - Qian Zhang
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
| | - Melissa A. Linden
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
| | - Nate Schacher
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
| | - Sanna Darvish
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
| | - Emily T. Mirek
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, NB, United States
| | - Jordan L. Levy
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, NB, United States
| | - William O. Jonsson
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, NB, United States
| | - Tracy G. Anthony
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, NB, United States
| | - Karyn L. Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States,Columbine Health Systems Center for Healthy Aging, Colorado State University, Fort Collins, CO, United States,*Correspondence: Karyn L. Hamilton,
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9
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Wachoski-Dark E, Zhao T, Khan A, Shutt TE, Greenway SC. Mitochondrial Protein Homeostasis and Cardiomyopathy. Int J Mol Sci 2022; 23:ijms23063353. [PMID: 35328774 PMCID: PMC8953902 DOI: 10.3390/ijms23063353] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 03/15/2022] [Accepted: 03/17/2022] [Indexed: 12/06/2022] Open
Abstract
Human mitochondrial disorders impact tissues with high energetic demands and can be associated with cardiac muscle disease (cardiomyopathy) and early mortality. However, the mechanistic link between mitochondrial disease and the development of cardiomyopathy is frequently unclear. In addition, there is often marked phenotypic heterogeneity between patients, even between those with the same genetic variant, which is also not well understood. Several of the mitochondrial cardiomyopathies are related to defects in the maintenance of mitochondrial protein homeostasis, or proteostasis. This essential process involves the importing, sorting, folding and degradation of preproteins into fully functional mature structures inside mitochondria. Disrupted mitochondrial proteostasis interferes with mitochondrial energetics and ATP production, which can directly impact cardiac function. An inability to maintain proteostasis can result in mitochondrial dysfunction and subsequent mitophagy or even apoptosis. We review the known mitochondrial diseases that have been associated with cardiomyopathy and which arise from mutations in genes that are important for mitochondrial proteostasis. Genes discussed include DnaJ heat shock protein family member C19 (DNAJC19), mitochondrial import inner membrane translocase subunit TIM16 (MAGMAS), translocase of the inner mitochondrial membrane 50 (TIMM50), mitochondrial intermediate peptidase (MIPEP), X-prolyl-aminopeptidase 3 (XPNPEP3), HtraA serine peptidase 2 (HTRA2), caseinolytic mitochondrial peptidase chaperone subunit B (CLPB) and heat shock 60-kD protein 1 (HSPD1). The identification and description of disorders with a shared mechanism of disease may provide further insights into the disease process and assist with the identification of potential therapeutics.
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Affiliation(s)
- Emily Wachoski-Dark
- Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada;
- Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Tian Zhao
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada;
| | - Aneal Khan
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada;
- Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
- M.A.G.I.C. Inc., Calgary, AB T2E 7Z4, Canada
| | - Timothy E. Shutt
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada;
- Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
- Correspondence: (T.E.S.); (S.C.G.)
| | - Steven C. Greenway
- Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada;
- Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada;
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada;
- Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
- Correspondence: (T.E.S.); (S.C.G.)
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10
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Brown JL, Lawrence MM, Borowik A, Oliver L, Peelor FF, Van Remmen H, Miller BF. Tumor burden negatively impacts protein turnover as a proteostatic process in noncancerous liver, heart, and muscle, but not brain. J Appl Physiol (1985) 2021; 131:72-82. [PMID: 34013745 DOI: 10.1152/japplphysiol.01026.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Cancer survivors are more susceptible to pathologies such as hypertension, liver disease, depression, and coronary artery disease when compared with individuals who have never been diagnosed with cancer. Therefore, it is important to understand how tumor burden negatively impacts nontumor-bearing tissues that may impact future disease susceptibility. We hypothesized that the energetic costs of a tumor would compromise proteostatic maintenance in other tissues. Therefore, the purpose of this study was to determine if tumor burden changes protein synthesis and proliferation rates in heart, brain, and liver. One million Lewis lung carcinoma (LLC) cells or phosphate-buffered saline (PBS, sham) were injected into the hind flank of female mice at ∼4.5 mo of age, and the tumor developed for 3 wk. Rates of proliferation and protein synthesis were measured in heart, brain, liver, and tumor tissue. Compared with sham, rates of protein synthesis (structural/nuclear, cytosolic, mitochondrial, and collagen) relative to proliferation were lower in the heart and liver of LLC mice, but higher in the brain of LLC mice. In the tumor tissue, the ratio of protein synthesis to DNA synthesis was approximately 1.0 showing that protein synthesis in the tumor was used for proliferation with little proteostatic maintenance. We further provide evidence that the differences in tissue responses may be due to energetic stress. We concluded that the decrease in proteostatic maintenance in liver, heart, and muscle might contribute to the increased risk of disease in cancer survivors.NEW & NOTEWORTHY We present data showing that simultaneously measuring protein synthesis and cell proliferation can help in the understanding of protein turnover as a proteostatic process in response to tumor burden. In some tissues, like hepatic, cardiac, and skeletal muscle, there was a decrease in the protein to DNA synthesis ratio indicating less proteostatic maintenance. In contrast, the brain maintained or even increased this protein to DNA synthesis ratio indicating more proteostatic maintenance.
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Affiliation(s)
- Jacob L Brown
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Marcus M Lawrence
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma.,Department of Kinesiology and Outdoor Recreation, Southern Utah University, Cedar City, Utah
| | - Agnieszka Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Lauren Oliver
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma.,Oklahoma University Health Science Center, Oklahoma City, Oklahoma
| | - Fredrick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Holly Van Remmen
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma.,Oklahoma City VA Medical Center, Oklahoma City, Oklahoma
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
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11
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Abbott CB, Lawrence MM, Kobak KA, Lopes EBP, Peelor FF, Donald EJ, Van Remmen H, Griffin TM, Miller BF. A Novel Stable Isotope Approach Demonstrates Surprising Degree of Age-Related Decline in Skeletal Muscle Collagen Proteostasis. FUNCTION (OXFORD, ENGLAND) 2021; 2:zqab028. [PMID: 34124684 PMCID: PMC8187230 DOI: 10.1093/function/zqab028] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/08/2021] [Accepted: 05/07/2021] [Indexed: 02/06/2023]
Abstract
Age-related deterioration in turnover of collagen proteins accelerates extracellular matrix fibrosis and hinders adaptation to external stimuli. This project sought to understand factors that increase skeletal muscle fibrosis with age by studying what we term the dynamic protein pool. We hypothesized that the dynamic protein pool size of muscle collagen decreases with age, thus indicating a decrease in proteostatic maintenance (ie, ability to maintain proteostasis), and that failure to account for these changes impacts the interpretation of tracer-measured synthesis rates. We used deuterium oxide (D2O) labeling for up to 60 days in adult (6 months) and old (23 months) mice. The dynamic protein pool in adult skeletal muscle was 65% in tibialis anterior (TA), but only 28% in gastrocnemius (Gastroc). In aged muscle, the dynamic protein pool was further decreased to only 35% and 14% for TA and Gastroc, respectively. We showed that this loss in dynamic pool size was associated with increases in markers of fibrosis and decreased proteostatic maintenance. We demonstrate that aged muscle has higher rates of collagen protein synthesis and lower rates of collagen protein breakdown, which causes collagen accumulation. We further demonstrated that the normal assumption of complete protein renewal and the standard practice of taking a single sample with isotope labeling have profound impacts on interpretation of the genesis of fibrosis. Strategies to maintain muscle function with aging should focus on the dynamic protein pool with attention to methodological strategies to assess those changes.
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Affiliation(s)
| | | | - Kamil A Kobak
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Erika Barboza Prado Lopes
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Elizabeth J Donald
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Holly Van Remmen
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Timothy M Griffin
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
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12
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Jonsson WO, Margolies NS, Mirek ET, Zhang Q, Linden MA, Hill CM, Link C, Bithi N, Zalma B, Levy JL, Pettit AP, Miller JW, Hine C, Morrison CD, Gettys TW, Miller BF, Hamilton KL, Wek RC, Anthony TG. Physiologic Responses to Dietary Sulfur Amino Acid Restriction in Mice Are Influenced by Atf4 Status and Biological Sex. J Nutr 2021; 151:785-799. [PMID: 33512502 PMCID: PMC8030708 DOI: 10.1093/jn/nxaa396] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 10/19/2020] [Accepted: 11/17/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Dietary sulfur amino acid restriction (SAAR) improves body composition and metabolic health across several model organisms in part through induction of the integrated stress response (ISR). OBJECTIVE We investigate the hypothesis that activating transcription factor 4 (ATF4) acts as a converging point in the ISR during SAAR. METHODS Using liver-specific or global gene ablation strategies, in both female and male mice, we address the role of ATF4 during dietary SAAR. RESULTS We show that ATF4 is dispensable in the chronic induction of the hepatokine fibroblast growth factor 21 while being essential for the sustained production of endogenous hydrogen sulfide. We also affirm that biological sex, independent of ATF4 status, is a determinant of the response to dietary SAAR. CONCLUSIONS Our results suggest that auxiliary components of the ISR, which are independent of ATF4, are critical for SAAR-mediated improvements in metabolic health in mice.
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Affiliation(s)
- William O Jonsson
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
| | | | - Emily T Mirek
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Qian Zhang
- Department of Health and Exercise Science, Colorado State University, Ft. Collins, CO, USA
| | - Melissa A Linden
- Department of Health and Exercise Science, Colorado State University, Ft. Collins, CO, USA
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, USA
| | - Cristal M Hill
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, USA
| | - Christopher Link
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, OH, USA
| | - Nazmin Bithi
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, OH, USA
| | - Brian Zalma
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Jordan L Levy
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Ashley P Pettit
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Joshua W Miller
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Christopher Hine
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, OH, USA
| | | | - Thomas W Gettys
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, USA
| | - Benjamin F Miller
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University, Ft. Collins, CO, USA
| | - Ronald C Wek
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
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13
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Miller BF, Pharaoh GA, Hamilton KL, Peelor FF, Kirkland JL, Freeman WM, Mann SN, Kinter M, Price JC, Stout MB. Short-term Calorie Restriction and 17α-Estradiol Administration Elicit Divergent Effects on Proteostatic Processes and Protein Content in Metabolically Active Tissues. J Gerontol A Biol Sci Med Sci 2021; 75:849-857. [PMID: 31074767 DOI: 10.1093/gerona/glz113] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Indexed: 12/11/2022] Open
Abstract
17α-Estradiol (17α-E2) is a "non-feminizing" estrogen that extends life span in male, but not female, mice. We recently reported that 17α-E2 had robust beneficial effects on metabolic and inflammatory parameters in aged male mice. However, it remains unclear if 17α-E2 also delays other "hallmarks" of aging, particularly maintaining proteostasis. Here, we used isotope labeling methods in older mice to examine proteostatic mechanisms. We compared weight-matched mild calorie restricted (CR) and 17α-E2 treated male mice with the hypothesis that 17α-E2 would increase protein synthesis for somatic maintenance. 17α-E2 had no effect on protein synthesis or DNA synthesis in multiple tissues, including white adipose tissue. Conversely, mild short-term CR decreased DNA synthesis and increased the protein to DNA synthesis ratio in multiple tissues. Examination of individual protein synthesis and content did not differentiate treatments, although it provided insight into the regulation of protein content between tissues. Contrary to our hypothesis, we did not see the predicted differences in protein to DNA synthesis following 17α-E2 treatment. However, mild short-term CR elicited differences consistent with both lifelong CR and other treatments that curtail aging processes. These data indicated that despite similar maintenance of body mass, 17α-E2 and CR treatments elicit distinctly different proteostatic outcomes.
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Affiliation(s)
- Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Fort Collins
| | - Gavin A Pharaoh
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Fort Collins.,Department of Physiology, University of Oklahoma Health Sciences Center, Fort Collins
| | - Karyn L Hamilton
- Health and Exercise Science Department, Colorado State University, Fort Collins
| | - Fredrick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Fort Collins
| | - James L Kirkland
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Willard M Freeman
- Department of Physiology, University of Oklahoma Health Sciences Center, Fort Collins.,Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Provo, Utah.,Oklahoma City Veterans Affairs Medical Center, Provo, Utah
| | - Shivani N Mann
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Provo, Utah.,Department of Nutritional Sciences, University of Oklahoma Health Sciences Center, Provo, Utah
| | - Michael Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Fort Collins
| | - John C Price
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah
| | - Michael B Stout
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Provo, Utah.,Department of Nutritional Sciences, University of Oklahoma Health Sciences Center, Provo, Utah
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14
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Gohel D, Singh R. Mitohormesis; Potential implications in neurodegenerative diseases. Mitochondrion 2020; 56:40-46. [PMID: 33220499 DOI: 10.1016/j.mito.2020.11.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 10/06/2020] [Accepted: 11/11/2020] [Indexed: 02/07/2023]
Abstract
Mitochondrial dysfunction is known to be associated with neurodegenerative diseases (NDDs), which is a major burden on the society. Therefore, understanding the regulation of mitochondrial dysfunctions and its implication in neurodegeneration has been major goal for exploiting these mechanisms to rescue neuronal death. The crosstalk between mitochondria and nucleus is important for different neuronal functions including axonal branching, energy homeostasis, neuroinflammation and neuronal survival. The decreased mitochondria capacity during progressive neurodegeneration leads to the altered OXPHOS activity and generation of ROS. The ROS levels in narrow physiological range can reprogram nuclear gene expression to enhance the cellular survival by phenomenon called mitohormesis. Here, we have systematically reviewed the existing reports of mitochondrial dysfunctions causing altered ROS levels in NDDs. We further discussed the role of ROS in regulating mitohormesis and emphasized the importance of mitohormesis in neuronal homeostasis. The emerging role of mitohormesis highlights its importance in future studies on intracellular ROS mediated rescue of mitochondrial dysfunction along with other prevailing mechanisms to alleviate neurodegeneration.
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Affiliation(s)
- Dhruv Gohel
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390002, Gujarat, India
| | - Rajesh Singh
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390002, Gujarat, India.
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15
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Daurio NA, Zhou H, Chen Y, Sheth PR, Imbriglio JE, McLaren DG, Tawa P, Rachdaoui N, Previs MJ, Kasumov T, O’Neil J, Previs SF. Examining Targeted Protein Degradation from Physiological and Analytical Perspectives: Enabling Translation between Cells and Subjects. ACS Chem Biol 2020; 15:2623-2635. [PMID: 32930572 DOI: 10.1021/acschembio.0c00380] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The ability to target specific proteins for degradation may open a new door toward developing therapeutics. Although effort in chemistry is essential for advancing this modality, i.e., one needs to generate proteolysis targeting chimeras (bifunctional molecules, also referred to as PROTACS) or "molecular glues" to accelerate protein degradation, we suspect that investigations could also benefit by directing attention toward physiological regulation surrounding protein homeostasis, including the methods that can be used to examine changes in protein kinetics. This perspective will first consider some metabolic scenarios that might be of importance when one aims to change protein abundance by increasing protein degradation. Specifically, could protein turnover impact the apparent outcome? We will then outline how to study protein dynamics by coupling stable isotope tracer methods with mass spectrometry-based detection; since the experimental conditions could have a dramatic effect on protein turnover, special attention is directed toward the application of methods for quantifying protein kinetics using in vitro and in vivo models. Our goal is to present key concepts that should enable mechanistically informed studies which test targeted protein degradation strategies.
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Affiliation(s)
- Natalie A. Daurio
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Haihong Zhou
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Ying Chen
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Payal R. Sheth
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Jason E. Imbriglio
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - David G. McLaren
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Paul Tawa
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Nadia Rachdaoui
- Department of Animal Sciences, Rutgers, the State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Michael J. Previs
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont 05454, United States
| | - Takhar Kasumov
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, Ohio 44272, United States
| | - Jennifer O’Neil
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
| | - Stephen F. Previs
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, New Jersey 07033, United States
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16
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Wolff CA, Reid JJ, Musci RV, Linden MA, Konopka AR, Peelor FF, Miller BF, Hamilton KL, Bruns DR. Differential Effects of Rapamycin and Metformin in Combination With Rapamycin on Mechanisms of Proteostasis in Cultured Skeletal Myotubes. J Gerontol A Biol Sci Med Sci 2020; 75:32-39. [PMID: 30820523 DOI: 10.1093/gerona/glz058] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 02/23/2019] [Indexed: 12/12/2022] Open
Abstract
mTOR inhibition extends life span in multiple organisms. In mice, when metformin treatment (Met) is added to the mTOR inhibitor rapamycin (Rap), median and maximal life span is extended to a greater degree than with Rap or Met alone. Treatments that extend life span often maintain proteostasis. However, it is less clear how individual tissues, such as skeletal muscle, maintain proteostasis with life span-extending treatments. In C2C12 myotubes, we used deuterium oxide (D2O) to directly measure two primary determinants of proteostasis, protein synthesis, and degradation rates, with Rap or Met+Rap treatments. We accounted for the independent effects of cell growth and loss, and isolated the contribution of autophagy and mitochondrial fission to obtain a comprehensive assessment of protein turnover. Compared with control, both Rap and Met+Rap treatments lowered mitochondrial protein synthesis rates (p < .001) and slowed cellular proliferation (p < .01). These changes resulted in greater activation of mechanisms promoting proteostasis for Rap, but not Met+Rap. Compared with control, both Rap and Met+Rap slowed protein breakdown. Autophagy and mitochondrial fission differentially influenced the proteostatic effects of Rap and Met+Rap in C2C12 myotubes. In conclusion, we demonstrate that Met+Rap did not increase protein turnover and that these treatments do not seem to promote proteostasis through increased autophagy.
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Affiliation(s)
- Christopher A Wolff
- Department of Health and Exercise Science, Colorado State University, Fort Collins
| | - Justin J Reid
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City
| | - Robert V Musci
- Department of Health and Exercise Science, Colorado State University, Fort Collins
| | - Melissa A Linden
- Department of Health and Exercise Science, Colorado State University, Fort Collins
| | - Adam R Konopka
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins
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17
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Reid JJ, Linden MA, Peelor FF, Miller RA, Hamilton KL, Miller BF. Brain Protein Synthesis Rates in the UM-HET3 Mouse Following Treatment With Rapamycin or Rapamycin With Metformin. J Gerontol A Biol Sci Med Sci 2020; 75:40-49. [PMID: 30864661 DOI: 10.1093/gerona/glz069] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Indexed: 12/12/2022] Open
Abstract
Treatment with the mechanistic target of rapamycin (mTOR) inhibitor, rapamycin (RAP), alone and in combination with the antidiabetic drug, metformin (RAP+MET), extends lifespan in mice. The mechanisms underlying lifespan extension are unclear. One possibility is improved capacity for proteostatic maintenance. We have previously characterized peripheral protein synthesis rates following treatment with RAP. However, it is unknown if RAP+MET elicits similar changes, or if either treatment affects protein synthesis in the brain. We hypothesized that 8 weeks of treatment with RAP and RAP+MET would alter brain protein synthesis rates to reflect proteostatic processes. Using the stable isotopic tracer, deuterium oxide (D2O), we demonstrate in UM-HET3 mice that protein synthesis rates measured in whole brain were unaffected by treatment in young male mice, whereas RAP+MET decreased mitochondrial protein synthesis in young females. Conversely, RAP increased mitochondrial protein synthesis rates in older females. Activity through the AMPK/mTOR pathway was affected in a sex-specific manner in young mice, and minimal changes were observed in the older cohort. Thus, we establish D2O for measurements of biogenesis in the brain. These results provide initial insights into the effects of RAP and RAP+MET on brain protein synthesis. Additionally, these data emphasize that responses to slowed aging treatments vary with sex and age.
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Affiliation(s)
- Justin J Reid
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City
| | - Melissa A Linden
- Department of Health and Exercise Science, Colorado State University, Fort Collins
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City
| | - Richard A Miller
- Department of Pathology and Paul F. Glenn Center, University of Michigan, Ann Arbor
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City
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18
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Wolff CA, Lawrence MM, Porter H, Zhang Q, Reid JJ, Laurin JL, Musci RV, Linden MA, Peelor FF, Wren JD, Creery JS, Cutler KJ, Carson RH, Price JC, Hamilton KL, Miller BF. Sex differences in changes of protein synthesis with rapamycin treatment are minimized when metformin is added to rapamycin. GeroScience 2020; 43:809-828. [PMID: 32761290 PMCID: PMC8110668 DOI: 10.1007/s11357-020-00243-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 07/29/2020] [Indexed: 12/18/2022] Open
Abstract
Loss of protein homeostasis is a hallmark of the aging process. We and others have previously shown that maintenance of proteostasis is a shared characteristic of slowed-aging models. Rapamycin (Rap) exerts sex-specific effects on murine lifespan, but the combination of Rap with the anti-hyperglycemic drug metformin (Rap + Met) equally increases male and female mouse median lifespan. In the current investigation, we compare the effects of short-term (8 weeks) Rap and Rap + Met treatments on bulk and individual protein synthesis in two key metabolic organs (the liver and skeletal muscle) of young genetically heterogeneous mice using deuterium oxide. We report for the first time distinct effects of Rap and Rap + Met treatments on bulk and individual protein synthesis in young mice. Although there were decreases in protein synthesis as assessed by bulk measurements, individual protein synthesis analyses demonstrate there were nearly as many proteins that increased synthesis as decreased synthesis rates. While we observed the established sex- and tissue-specific effects of Rap on protein synthesis, adding Met yielded more uniform effects between tissue and sex. These data offer mechanistic insight as to how Rap + Met may extend lifespan in both sexes while Rap does not.
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Affiliation(s)
- Christopher A Wolff
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523, USA.,Department of Physiology and Functional Genomics, University of Florida, Gainesville, 32610, USA
| | - Marcus M Lawrence
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA.
| | - Hunter Porter
- Genes and Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Qian Zhang
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523, USA
| | - Justin J Reid
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Jaime L Laurin
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Robert V Musci
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523, USA
| | - Melissa A Linden
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523, USA.,Pennington Biomedical Research Foundation, Baton Rouge, LA, 70808, USA
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Jonathan D Wren
- Genes and Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Joseph S Creery
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - Kyle J Cutler
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - Richard H Carson
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - John C Price
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
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19
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Groennebaek T, Nielsen J, Jespersen NR, Bøtker HE, de Paoli FV, Miller BF, Vissing K. Utilization of biomarkers as predictors of skeletal muscle mitochondrial content after physiological intervention and in clinical settings. Am J Physiol Endocrinol Metab 2020; 318:E886-E889. [PMID: 32255679 DOI: 10.1152/ajpendo.00101.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The measurement of mitochondrial content is essential for bioenergetic research, as it provides a tool to evaluate whether changes in mitochondrial function are strictly due to changes in content or other mechanisms that influence function. In this perspective, we argue that commonly used biomarkers of mitochondrial content may possess limited utility for capturing changes in content with physiological intervention. Moreover, we argue that they may not provide reliable estimates of content in certain pathological situations. Finally, we discuss potential solutions to overcome issues related to the utilization of biomarkers of mitochondrial content. Shedding light on this important issue will hopefully aid conclusions about the mitochondrial structure-function relationship.
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Affiliation(s)
| | - Joachim Nielsen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | | | - Hans Erik Bøtker
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
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20
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Basisty N, Holtz A, Schilling B. Accumulation of "Old Proteins" and the Critical Need for MS-based Protein Turnover Measurements in Aging and Longevity. Proteomics 2020; 20:e1800403. [PMID: 31408259 PMCID: PMC7015777 DOI: 10.1002/pmic.201800403] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 07/31/2019] [Indexed: 12/31/2022]
Abstract
Aging and age-related diseases are accompanied by proteome remodeling and progressive declines in cellular machinery required to maintain protein homeostasis (proteostasis), such as autophagy, ubiquitin-mediated degradation, and protein synthesis. While many studies have focused on capturing changes in proteostasis, the identification of proteins that evade these cellular processes has recently emerged as an approach to studying the aging proteome. With advances in proteomic technology, it is possible to monitor protein half-lives and protein turnover at the level of individual proteins in vivo. For large-scale studies, these technologies typically include the use of stable isotope labeling coupled with MS and comprehensive assessment of protein turnover rates. Protein turnover studies have revealed groups of highly relevant long-lived proteins (LLPs), such as the nuclear pore complexes, extracellular matrix proteins, and protein aggregates. Here, the role of LLPs during aging and age-related diseases and the methods used to identify and quantify their changes are reviewed. The methods available to conduct studies of protein turnover, used in combination with traditional proteomic methods, will enable the field to perform studies in a systems biology context, as changes in proteostasis may not be revealed in studies that solely measure differential protein abundances.
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Affiliation(s)
| | - Anja Holtz
- The Buck Institute for Research on AgingNovatoCAUSA
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21
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Ehrlicher SE, Stierwalt HD, Miller BF, Newsom SA, Robinson MM. Mitochondrial adaptations to exercise do not require Bcl2-mediated autophagy but occur with BNIP3/Parkin activation. FASEB J 2020; 34:4602-4618. [PMID: 32030805 DOI: 10.1096/fj.201902594rr] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/11/2020] [Accepted: 01/17/2020] [Indexed: 12/27/2022]
Abstract
Understanding the mechanisms regulating mitochondrial respiratory function and adaptations to metabolic challenges, such as exercise and high dietary fat, is necessary to promote skeletal muscle health and attenuate metabolic disease. Autophagy is a constitutively active degradation pathway that promotes mitochondrial turnover and transiently increases postexercise. Recent evidence indicates Bcl2 mediates exercise-induced autophagy and skeletal muscle adaptions to training during high-fat diet. We determined if improvements in mitochondrial respiration due to exercise training required Bcl2-mediated autophagy using a transgenic mouse model of impaired inducible autophagy (Bcl2AAA ). Mitochondrial adaptations to a treadmill exercise training protocol, in either low-fat or high-fat diet fed mice, did not require Bcl2-mediated autophagy activation. Instead, training increased protein synthesis rates and basal autophagy in the Bcl2AAA mice, while acute exercise activated BNIP3 and Parkin autophagy. High-fat diet stimulated lipid-specific mitochondrial adaptations. These data demonstrate increases in basal mitochondrial turnover, not transient activation with exercise, mediate adaptations to exercise and high-fat diet.
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Affiliation(s)
- Sarah E Ehrlicher
- School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA
| | - Harrison D Stierwalt
- School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Sean A Newsom
- School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA
| | - Matthew M Robinson
- School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA
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22
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Musci RV, Hamilton KL, Linden MA. Exercise-Induced Mitohormesis for the Maintenance of Skeletal Muscle and Healthspan Extension. Sports (Basel) 2019; 7:E170. [PMID: 31336753 PMCID: PMC6681340 DOI: 10.3390/sports7070170] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/07/2019] [Accepted: 07/09/2019] [Indexed: 12/25/2022] Open
Abstract
Oxidative damage is one mechanism linking aging with chronic diseases including the progressive loss of skeletal muscle mass and function called sarcopenia. Thus, mitigating oxidative damage is a potential avenue to prevent or delay the onset of chronic disease and/or extend healthspan. Mitochondrial hormesis (mitohormesis) occurs when acute exposure to stress stimulates adaptive mitochondrial responses that improve mitochondrial function and resistance to stress. For example, an acute oxidative stress via mitochondrial superoxide production stimulates the activation of endogenous antioxidant gene transcription regulated by the redox sensitive transcription factor Nrf2, resulting in an adaptive hormetic response. In addition, acute stresses such as aerobic exercise stimulate the expansion of skeletal muscle mitochondria (i.e., mitochondrial biogenesis), constituting a mitohormetic response that protects from sarcopenia through a variety of mechanisms. This review summarized the effects of age-related declines in mitochondrial and redox homeostasis on skeletal muscle protein homeostasis and highlights the mitohormetic mechanisms by which aerobic exercise mitigates these age-related declines and maintains function. We discussed the potential efficacy of targeting the Nrf2 signaling pathway, which partially mediates adaptation to aerobic exercise, to restore mitochondrial and skeletal muscle function. Finally, we highlight knowledge gaps related to improving redox signaling and make recommendations for future research.
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Affiliation(s)
- Robert V Musci
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO 80523, USA.
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO 80523, USA
| | - Melissa A Linden
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO 80523, USA
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23
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Jonsson WO, Margolies NS, Anthony TG. Dietary Sulfur Amino Acid Restriction and the Integrated Stress Response: Mechanistic Insights. Nutrients 2019; 11:nu11061349. [PMID: 31208042 PMCID: PMC6627990 DOI: 10.3390/nu11061349] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/07/2019] [Accepted: 06/11/2019] [Indexed: 12/17/2022] Open
Abstract
Dietary sulfur amino acid restriction, also referred to as methionine restriction, increases food intake and energy expenditure and alters body composition in rodents, resulting in improved metabolic health and a longer lifespan. Among the known nutrient-responsive signaling pathways, the evolutionary conserved integrated stress response (ISR) is a lesser-understood candidate in mediating the hormetic effects of dietary sulfur amino acid restriction (SAAR). A key feature of the ISR is the concept that a family of protein kinases phosphorylates eukaryotic initiation factor 2 (eIF2), dampening general protein synthesis to conserve cellular resources. This slowed translation simultaneously allows for preferential translation of genes with special sequence features in the 5' leader. Among this class of mRNAs is activating transcription factor 4 (ATF4), an orchestrator of transcriptional control during nutrient stress. Several ATF4 gene targets help execute key processes affected by SAAR such as lipid metabolism, the transsulfuration pathway, and antioxidant defenses. Exploration of the canonical ISR demonstrates that eIF2 phosphorylation is not necessary for ATF4-driven changes in the transcriptome during SAAR. Additional research is needed to clarify the regulation of ATF4 and its gene targets during SAAR.
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Affiliation(s)
- William O Jonsson
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ 08901, USA.
| | - Nicholas S Margolies
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ 08901, USA.
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ 08901, USA.
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24
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Miller BF, Hamilton KL. Overview: the modulation of ageing through altered proteostasis. J Physiol 2019; 595:6381-6382. [PMID: 29027211 DOI: 10.1113/jp274997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Benjamin F Miller
- Translational Research on Aging and Chronic Disease Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523-1582, USA
| | - Karyn L Hamilton
- Translational Research on Aging and Chronic Disease Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523-1582, USA
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25
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Bruns DR, Ehrlicher SE, Khademi S, Biela LM, Peelor FF, Miller BF, Hamilton KL. Differential effects of vitamin C or protandim on skeletal muscle adaptation to exercise. J Appl Physiol (1985) 2018; 125:661-671. [PMID: 29856263 PMCID: PMC6139515 DOI: 10.1152/japplphysiol.00277.2018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/24/2018] [Accepted: 05/24/2018] [Indexed: 12/31/2022] Open
Abstract
Maintaining proteostasis is a key mechanism for preserving cell function. Exercise-stimulated proteostasis is regulated, in part, by redox-sensitive signaling. Several studies suggest that supplementation with exogenous antioxidants blunts exercise-induced cellular adaptations, although this conclusion lacks consensus. Our group uses a fundamentally different approach to maintain redox balance by treatment with bioactive phytochemicals to activate the transcription factor nuclear factor (erythroid-derived 2)-like 2 and downstream endogenous antioxidant pathways. We hypothesized that vitamin C (VitC) would interfere with redox-sensitive proteostatic mechanisms in skeletal muscle, whereas phytochemical treatment would permit proteostatic maintenance. We measured protein and DNA synthesis in skeletal muscle from high-volume voluntary wheel-running rats. Whereas phytochemical treatment permitted mitochondrial and other proteostatic adaptations to exercise, VitC treatment did not. During an in vitro oxidative challenge, phytochemical treatment helped maintain proteostasis, including the mitochondrial fraction while VitC did not. Our findings support the conclusion that VitC can blunt some of the beneficial adaptations to exercise. We propose that regulation of endogenous antioxidants represents a novel approach to maintain redox balance while still permitting redox-sensitive proteostatic adaptations. NEW & NOTEWORTHY Whether vitamin C blocks aerobic exercise adaptions lacks consensus, perhaps because of approaches that only assess markers of mitochondrial biogenesis. By directly measuring mitochondrial biogenesis, we demonstrate that vitamin C blunts exercise-induced adaptations. Furthermore, we show that treatment with Protandim, a purported nuclear factor (erythroid-derived 2)-like 2 activator that upregulates endogenous antioxidants, permits mitochondrial biogenesis. We confirm that vitamin C blunts aerobic exercise adaptions, whereas Protandim does not, suggesting targeting the endogenous antioxidant network facilitates adaptations to exercise.
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Affiliation(s)
- Danielle R Bruns
- Department of Health and Exercise Science, Colorado State University , Fort Collins, Colorado
| | - Sarah E Ehrlicher
- Department of Health and Exercise Science, Colorado State University , Fort Collins, Colorado
| | - Shadi Khademi
- Department of Health and Exercise Science, Colorado State University , Fort Collins, Colorado
| | - Laurie M Biela
- Department of Health and Exercise Science, Colorado State University , Fort Collins, Colorado
| | - Frederick F Peelor
- Department of Health and Exercise Science, Colorado State University , Fort Collins, Colorado
| | - Benjamin F Miller
- Department of Health and Exercise Science, Colorado State University , Fort Collins, Colorado
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University , Fort Collins, Colorado
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26
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Musci RV, Hamilton KL, Miller BF. Targeting mitochondrial function and proteostasis to mitigate dynapenia. Eur J Appl Physiol 2018; 118:1-9. [PMID: 28986697 PMCID: PMC5756099 DOI: 10.1007/s00421-017-3730-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 09/30/2017] [Indexed: 12/25/2022]
Abstract
Traditionally, interventions to treat skeletal muscle aging have largely targeted sarcopenia-the age-related loss of skeletal muscle mass. Dynapenia refers to the age-related loss in skeletal muscle function due to factors outside of muscle mass, which helps to inform treatment strategies for aging skeletal muscle. There is evidence that mechanisms to maintain protein homeostasis and proteostasis, deteriorate with age. One key mechanism to maintain proteostasis is protein turnover, which is an energetically costly process. When there is a mismatch between cellular energy demands and energy provision, inelastic processes related to metabolism are maintained, but there is competition for the remaining energy between the elastic processes of somatic maintenance and growth. With aging, mitochondrial dysfunction reduces ATP generation capacity, constraining the instantaneous supply of energy, thus compromising growth and somatic maintenance processes. Further, with age the need for somatic maintenance increases because of the accumulation of protein damage. In this review, we highlight the significant role mitochondria have in maintaining skeletal muscle proteostasis through increased energy provision, protein turnover, and substrate flux. In addition, we provide evidence that improving mitochondrial function could promote a cellular environment that is conducive to somatic maintenance, and consequently for mitigating dynapenia. Finally, we highlight interventions, such as aerobic exercise, that could be used to improve mitochondrial function and improve outcomes related to dynapenia.
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Affiliation(s)
- Robert V Musci
- Translational Research on Aging and Chronic Disease Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523-1582, USA
| | - Karyn L Hamilton
- Translational Research on Aging and Chronic Disease Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523-1582, USA
| | - Benjamin F Miller
- Translational Research on Aging and Chronic Disease Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523-1582, USA.
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