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Pabis K, Barardo D, Gruber J, Sirbu O, Malavolta M, Selvarajoo K, Kaeberlein M, Kennedy BK. The impact of short-lived controls on the interpretation of lifespan experiments and progress in geroscience - through the lens of the "900-day rule". Ageing Res Rev 2024:102512. [PMID: 39332712 DOI: 10.1016/j.arr.2024.102512] [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: 12/07/2023] [Revised: 08/08/2024] [Accepted: 09/17/2024] [Indexed: 09/29/2024]
Abstract
Although lifespan extension remains the gold standard for assessing interventions proposed to impact the biology of aging, there are important limitations to this approach. Our reanalysis of lifespan studies from multiple sources suggests that short lifespans in the control group exaggerate the relative efficacy of putative longevity interventions. Results may be exaggerated due to statistical effects (e.g. regression to the mean) or other factors. Moreover, due to the high cost and long timeframes of mouse studies, it is rare that a particular longevity intervention will be independently replicated by multiple groups. To facilitate identification of successful interventions, we propose an alternative approach particularly suitable for well-characterized inbred and HET3 mice. The level of confidence we can have in an intervention is proportional to the degree of lifespan extension above the strain- and species-specific upper limit of lifespan, which we can estimate from comparison to historical controls. In the absence of independent replication, a putative mouse longevity intervention should only be considered with high confidence when control median lifespans are close to 900 days or if the final lifespan of the treated group is considerably above 900 days. Using this "900-day rule" we identified several candidate interventions from the literature that merit follow-up studies.
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Affiliation(s)
- Kamil Pabis
- Healthy Longevity Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore; Centre for Healthy Longevity, National University Health System; Departments of Biochemistry and Physiology, Yong Loo Lin School of Medicine, National University of Singapore
| | - Diogo Barardo
- Healthy Longevity Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore; Centre for Healthy Longevity, National University Health System; NOVOS Labs, 100 Park Avenue, 16th Fl, New York NY 10017
| | - Jan Gruber
- Healthy Longevity Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore; Departments of Biochemistry and Physiology, Yong Loo Lin School of Medicine, National University of Singapore; Science Divisions, Yale-NUS College, Singapore, 138527, Singapore
| | - Olga Sirbu
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A⁎STAR), Singapore, 138671, Republic of Singapore
| | - Marco Malavolta
- Advanced Technology Center for Aging Research and Geriatric Mouse Clinic, IRCCS INRCA, 60121, Ancona, Italy
| | - Kumar Selvarajoo
- Advanced Technology Center for Aging Research and Geriatric Mouse Clinic, IRCCS INRCA, 60121, Ancona, Italy; Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore (NUS), Singapore, 117456, Republic of Singapore; School of Biological Sciences, Nanyang Technological University (NTU), 639798, Republic of Singapore
| | | | - Brian K Kennedy
- Healthy Longevity Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore; Centre for Healthy Longevity, National University Health System; Departments of Biochemistry and Physiology, Yong Loo Lin School of Medicine, National University of Singapore; Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore.
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2
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Mitchell SE, Togo J, Green CL, Derous D, Hambly C, Speakman JR. The Effects of Graded Levels of Calorie Restriction: XX. Impact of Long-Term Graded Calorie Restriction on Survival and Body Mass Dynamics in Male C57BL/6J Mice. J Gerontol A Biol Sci Med Sci 2023; 78:1953-1963. [PMID: 37354128 PMCID: PMC10613020 DOI: 10.1093/gerona/glad152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Indexed: 06/26/2023] Open
Abstract
Calorie restriction (CR) typically promotes a reduction in body mass, which correlates with increased lifespan. We evaluated the overall changes in survival, body mass dynamics, and body composition following long-term graded CR (580 days/19 months) in male C57BL/6J mice. Control mice (0% restriction) were fed ad libitum in the dark phase only (12-hour ad libitum [12AL]). CR groups were restricted by 10%-40% of their baseline food intake (10CR, 20CR, 30CR, and 40CR). Body mass was recorded daily, and body composition was measured at 8 time points. At 728 days/24 months, all surviving mice were culled. A gradation in survival rate over the CR groups was found. The pattern of body mass loss differed over the graded CR groups. Whereas the lower CR groups rapidly resumed an energy balance with no significant loss of fat or fat-free mass, changes in the 30 and 40CR groups were attributed to higher fat-free mass loss and protection of fat mass. Day-to-day changes in body mass were less variable under CR than for the 12AL group. There was no indication that body mass was influenced by external factors. Partial autocorrelation analysis examined the relationship between daily changes in body masses. A negative correlation between mass on Day 0 and Day +1 declined with age in the 12AL but not the CR groups. A reduction in the correlation with age suggested body mass homeostasis is a marker of aging that declines at the end of life and is protected by CR.
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Affiliation(s)
| | - Jacques Togo
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - Cara L Green
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - Davina Derous
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - Catherine Hambly
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - John R Speakman
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
- Shenzhen Key Laboratory of Metabolic Health, Center for Energy Metabolism and Reproduction, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, P.R. China
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, P.R. China
- China Medical University, Shenyang, Liaoning, P.R. China
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3
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Roy S, Sleiman MB, Jha P, Ingels JF, Chapman CJ, McCarty MS, Ziebarth JD, Hook M, Sun A, Zhao W, Huang J, Neuner SM, Wilmott LA, Shapaker TM, Centeno AG, Ashbrook DG, Mulligan MK, Kaczorowski CC, Makowski L, Cui Y, Read RW, Miller RA, Mozhui K, Williams EG, Sen S, Lu L, Auwerx J, Williams RW. Gene-by-environment modulation of lifespan and weight gain in the murine BXD family. Nat Metab 2021; 3:1217-1227. [PMID: 34552269 PMCID: PMC8478125 DOI: 10.1038/s42255-021-00449-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 08/06/2021] [Indexed: 02/07/2023]
Abstract
How lifespan and body weight vary as a function of diet and genetic differences is not well understood. Here we quantify the impact of differences in diet on lifespan in a genetically diverse family of female mice, split into matched isogenic cohorts fed a low-fat chow diet (CD, n = 663) or a high-fat diet (HFD, n = 685). We further generate key metabolic data in a parallel cohort euthanized at four time points. HFD feeding shortens lifespan by 12%: equivalent to a decade in humans. Initial body weight and early weight gains account for longevity differences of roughly 4-6 days per gram. At 500 days, animals on a HFD typically gain four times as much weight as control, but variation in weight gain does not correlate with lifespan. Classic serum metabolites, often regarded as health biomarkers, are not necessarily strong predictors of longevity. Our data indicate that responses to a HFD are substantially modulated by gene-by-environment interactions, highlighting the importance of genetic variation in making accurate individualized dietary recommendations.
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Affiliation(s)
- Suheeta Roy
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Maroun Bou Sleiman
- Laboratory of Integrative Systems Physiology, Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Pooja Jha
- Laboratory of Integrative Systems Physiology, Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Jesse F Ingels
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Casey J Chapman
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Melinda S McCarty
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Jesse D Ziebarth
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Michael Hook
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Anna Sun
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Wenyuan Zhao
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Jinsong Huang
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Sarah M Neuner
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Lynda A Wilmott
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Thomas M Shapaker
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Arthur G Centeno
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - David G Ashbrook
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Megan K Mulligan
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | | | - Liza Makowski
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Yan Cui
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Robert W Read
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Richard A Miller
- Department of Pathology, University of Michigan Geriatrics Center, Ann Arbor, MI, USA
| | - Khyobeni Mozhui
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Evan G Williams
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Saunak Sen
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Lu Lu
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Johan Auwerx
- Laboratory of Integrative Systems Physiology, Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Robert W Williams
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA.
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4
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Arum O, Dawson JA, Smith DL, Kopchick JJ, Allison DB, Bartke A. Do altered energy metabolism or spontaneous locomotion 'mediate' decelerated senescence? Aging Cell 2015; 14:483-90. [PMID: 25720347 PMCID: PMC4406677 DOI: 10.1111/acel.12318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2015] [Indexed: 12/01/2022] Open
Abstract
That one or multiple measures of metabolic rate may be robustly associated with, or possibly even causative of, the progression of aging-resultant phenotypes such as lifespan is a long-standing, well-known mechanistic hypothesis. To broach this hypothesis, we assessed metabolic function and spontaneous locomotion in two genetic and one dietary mouse models for retarded aging, and subjected the data to mediation analyses to determine whether any metabolic or locomotor trait could be identified as a mediator of the effect of any of the interventions on senescence. We do not test the hypothesis of causality (which would require some experiments), but instead test whether the correlation structure of certain variables is consistent with one possible pathway model in which a proposed mediating variable has a causal role. Results for metabolic measures, including oxygen consumption and respiratory quotient, failed to support this hypothesis; similar negative results were obtained for three behavioral motion metrics. Therefore, our mediation analyses did not find support that any of these correlates of decelerated senescence was a substantial mediator of the effect of either of these genetic alterations (with or without caloric restriction) on longevity. Further studies are needed to relate the examined phenotypic characteristics to mechanisms of aging and control of longevity.
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Affiliation(s)
- Oge Arum
- Department of Internal Medicine Southern Illinois University‐School of Medicine Springfield IL 62794 USA
| | - John Alexander Dawson
- Section on Statistical Genetics Department of Biostatistics School of Public Health University of Alabama at Birmingham 1665 University Blvd RPHB 140J Birmingham AL 35294‐0022 USA
| | - Daniel Larry Smith
- Nutrition Obesity Research Center Department of Nutrition Sciences University of Alabama at Birmingham Birmingham AL 35294‐0022 USA
| | - John J. Kopchick
- Department of Biomedical Sciences Edison Biotechnology Institute Heritage College of Osteopathic Medicine Ohio University Athens OH 45701 USA
| | - David B. Allison
- Section on Statistical Genetics Department of Biostatistics School of Public Health University of Alabama at Birmingham 1665 University Blvd RPHB 140J Birmingham AL 35294‐0022 USA
- Nutrition Obesity Research Center Department of Nutrition Sciences University of Alabama at Birmingham Birmingham AL 35294‐0022 USA
| | - Andrzej Bartke
- Department of Internal Medicine Southern Illinois University‐School of Medicine Springfield IL 62794 USA
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Arum O, Saleh J, Boparai R, Turner J, Kopchick J, Khardori R, Bartke A. Interaction of growth hormone receptor/binding protein gene disruption and caloric restriction for insulin sensitivity and attenuated aging. F1000Res 2014; 3:256. [PMID: 25789159 PMCID: PMC4358413 DOI: 10.12688/f1000research.5378.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/27/2014] [Indexed: 11/20/2022] Open
Abstract
The correlation of physiological sensitivity to insulin ( vis-à-vis glycemic regulation) and longevity is extensively established, creating a justifiable gerontological interest on whether insulin sensitivity is causative, or even predictive, of some or all phenotypes of slowed senescence (including longevity). The growth hormone receptor/ binding protein gene-disrupted (GHR-KO) mouse is the most extensively investigated insulin-sensitive, attenuated aging model. It was reported that, in a manner divergent from similar mutants, GHR-KO mice fail to respond to caloric restriction (CR) by altering their insulin sensitivity. We hypothesized that maximized insulin responsiveness is what causes GHR-KO mice to exhibit a suppressed survivorship response to dietary (including caloric) restriction; and attempted to refute this hypothesis by assessing the effects of CR on GHR-KO mice for varied slow-aging-associated phenotypes. In contrast to previous reports, we found GHR-KO mice on CR to be less responsive than their ad libitum (A.L.) counterparts to the hypoglycemia-inducing effects of insulin. Further, CR had negligible effects on the metabolism or cognition of GHR-KO mice. Therefore, our data suggest that the effects of CR on the insulin sensitivity of GHR-KO mice do not concur with the effects of CR on the aging of GHR-KO mice.
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Affiliation(s)
- Oge Arum
- Department of Internal Medicine, Southern Illinois University-School of Medicine, Springfield, IL, 62794, USA
| | - Jamal Saleh
- Department of Internal Medicine, Southern Illinois University-School of Medicine, Springfield, IL, 62794, USA
| | - Ravneet Boparai
- Department of Internal Medicine, Southern Illinois University-School of Medicine, Springfield, IL, 62794, USA
| | - Jeremy Turner
- Department of Surgery, Division of ENT-Otolaryngology, Southern Illinois University-School of Medicine, Springfield, IL, 62794, USA
| | - John Kopchick
- Edison Biotechnology Institute and Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, 45701, USA
| | - Romesh Khardori
- Department of Internal Medicine, Division of Endocrinology & Metabolism, Eastern Virginia Medical School, Norfolk, VA, 23507, USA
| | - Andrzej Bartke
- Department of Internal Medicine, Southern Illinois University-School of Medicine, Springfield, IL, 62794, USA
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6
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Sohal RS, Forster MJ. Caloric restriction and the aging process: a critique. Free Radic Biol Med 2014; 73:366-82. [PMID: 24941891 PMCID: PMC4111977 DOI: 10.1016/j.freeradbiomed.2014.05.015] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/16/2014] [Accepted: 05/17/2014] [Indexed: 01/06/2023]
Abstract
The main objective of this review is to provide an appraisal of the current status of the relationship between energy intake and the life span of animals. The concept that a reduction in food intake, or caloric restriction (CR), retards the aging process, delays the age-associated decline in physiological fitness, and extends the life span of organisms of diverse phylogenetic groups is one of the leading paradigms in gerontology. However, emerging evidence disputes some of the primary tenets of this conception. One disparity is that the CR-related increase in longevity is not universal and may not even be shared among different strains of the same species. A further misgiving is that the control animals, fed ad libitum (AL), become overweight and prone to early onset of diseases and death, and thus may not be the ideal control animals for studies concerned with comparisons of longevity. Reexamination of body weight and longevity data from a study involving over 60,000 mice and rats, conducted by a National Institute on Aging-sponsored project, suggests that CR-related increase in life span of specific genotypes is directly related to the gain in body weight under the AL feeding regimen. Additionally, CR in mammals and "dietary restriction" in organisms such as Drosophila are dissimilar phenomena, albeit they are often presented to be the very same. The latter involves a reduction in yeast rather than caloric intake, which is inconsistent with the notion of a common, conserved mechanism of CR action in different species. Although specific mechanisms by which CR affects longevity are not well understood, existing evidence supports the view that CR increases the life span of those particular genotypes that develop energy imbalance owing to AL feeding. In such groups, CR lowers body temperature, rate of metabolism, and oxidant production and retards the age-related pro-oxidizing shift in the redox state.
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Affiliation(s)
- Rajindar S Sohal
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA.
| | - Michael J Forster
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
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Prevention of neuromusculoskeletal frailty in slow-aging ames dwarf mice: longitudinal investigation of interaction of longevity genes and caloric restriction. PLoS One 2013; 8:e72255. [PMID: 24155868 PMCID: PMC3796515 DOI: 10.1371/journal.pone.0072255] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 07/12/2013] [Indexed: 11/19/2022] Open
Abstract
Ames dwarf (Prop1df/df) mice are remarkably long-lived and exhibit many characteristics of delayed aging and extended healthspan. Caloric restriction (CR) has similar effects on healthspan and lifespan, and causes an extension of longevity in Ames dwarf mice. Our study objective was to determine whether Ames dwarfism or CR influence neuromusculoskeletal function in middle-aged (82 ± 12 weeks old) or old (128 ± 14 w.o.) mice. At the examined ages, strength was improved by dwarfism, CR, and dwarfism plus CR in male mice; balance/ motor coordination was improved by CR in old animals and in middle-aged females; and agility/ motor coordination was improved by a combination of dwarfism and CR in both genders of middle-aged mice and in old females. Therefore, extension of longevity by congenital hypopituitarism is associated with improved maintenance of the examined measures of strength, agility, and motor coordination, key elements of frailty during human aging, into advanced age. This study serves as a particularly important example of knowledge related to addressing aging-associated diseases and disorders that results from studies in long-lived mammals.
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Liao CY, Johnson TE, Nelson JF. Genetic variation in responses to dietary restriction--an unbiased tool for hypothesis testing. Exp Gerontol 2013; 48:1025-9. [PMID: 23562825 DOI: 10.1016/j.exger.2013.03.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Revised: 03/07/2013] [Accepted: 03/27/2013] [Indexed: 11/19/2022]
Abstract
Dietary restriction (DR) extends lifespan in a wide range of animal models. A major obstacle to understanding how DR modulates lifespan and aging-related dysfunction is the multiplicity of physiological and molecular changes associated with DR. Unraveling their importance to the longevity effect of DR remains a major challenge. In this perspective, we review the marked genetic variation in the response to DR of multiple recombinant inbred (RI) mouse strains. We illustrate how this genetic variation can be exploited to probe the mechanisms mediating lifespan extension by DR, as well as uncover its limits as an intervention. RI strains exhibit marked variation in their lifespan as well as physiological responses to DR. Quantitative genetic and statistical tools can use this phenotypic variation to probe the importance of physiological and molecular changes that have been hypothesized to play roles in DR-mediated lifespan extension.
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Affiliation(s)
- Chen-Yu Liao
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, United States
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10
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Johnson MA, Dwyer JT, Jensen GL, Miller JW, Speakman JR, Starke-Reed P, Volpi E. Challenges and new opportunities for clinical nutrition interventions in the aged. J Nutr 2011; 141:535-41. [PMID: 21270372 PMCID: PMC3138222 DOI: 10.3945/jn.110.131425] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Nutritional status plays a critical role in the prevention and management of many chronic health conditions that are common in the elderly and are likely to become more prevalent as the population ages. This paper highlights several aspects of nutrition that require additional basic science and clinical application research to improve the health and well-being of older adults. Topics addressed are selected demographic and health indices, the uncertain benefits of energy restriction in aged humans compared with other species, the impact of food insecurity on health, the relationship between dietary protein and sarcopenia, the prevention and management of obesity while maintaining muscle mass and functional status, and controversy regarding high intakes of folic acid. Research needs regarding the safety, efficacy, and application of clinical interventions related to these topics also are discussed.
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Affiliation(s)
- Mary Ann Johnson
- Department of Foods and Nutrition, University of Georgia, Athens, GA 30602
| | - Johanna T. Dwyer
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD 20892
- Jean Mayer Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111
| | - Gordon L. Jensen
- Department of Nutritional Science, Pennsylvania State University, University Park, PA 16802
| | - Joshua W. Miller
- Department of Medical Pathology and Laboratory Medicine, University of California, Davis, CA 95817
| | - John R. Speakman
- Department of Zoology, University of Aberdeen, Aberdeen AB24 2TZ, Scotland
| | - Pamela Starke-Reed
- Division of Nutrition Research Coordination, National Institutes of Health, Bethesda, MD 20892
| | - Elena Volpi
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77555
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Rikke BA, Liao CY, McQueen MB, Nelson JF, Johnson TE. Genetic dissection of dietary restriction in mice supports the metabolic efficiency model of life extension. Exp Gerontol 2010; 45:691-701. [PMID: 20452416 DOI: 10.1016/j.exger.2010.04.008] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Revised: 04/15/2010] [Accepted: 04/26/2010] [Indexed: 11/18/2022]
Abstract
Dietary restriction (DR) has been used for decades to retard aging in rodents, but its mechanism of action remains an enigma. A principal roadblock has been that DR affects many different processes, making it difficult to distinguish cause and effect. To address this problem, we applied a quantitative genetics approach utilizing the ILSXISS series of mouse recombinant inbred strains. Across 42 strains, mean female lifespan ranged from 380 to 1070days on DR (fed 60% of ad libitum [AL]) and from 490 to 1020days on an AL diet. Longevity under DR and AL is under genetic control, showing 34% and 36% heritability, respectively. There was no correlation between lifespans on DR and AL; thus different genes modulate longevity under the two regimens. DR lifespans are significantly correlated with female fertility after return to an AL diet after various periods of DR (R=0.44, P=0.006). We assessed fuel efficiency (FE, ability to maintain growth and body weight independent of absolute food intake) using a multivariate approach and found it to be correlated with longevity and female fertility, suggesting possible causality. We found several quantitative trait loci responsible for these traits, mapping to chromosomes 7, 9, and 15. We present a metabolic model in which the anti-aging effects of DR are consistent with the ability to efficiently utilize dietary resources.
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Affiliation(s)
- Brad A Rikke
- Institute for Behavioral Genetics, University of Colorado at Boulder, Boulder, CO 80309, USA.
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12
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Liao CY, Rikke BA, Johnson TE, Diaz V, Nelson JF. No evidence that competition for food underlies lifespan shortening by dietary restriction in multiply housed mice: response to commentary. Aging Cell 2010. [DOI: 10.1111/j.1474-9726.2010.00564.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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