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Vessey KA, Jobling AI, Greferath U, Fletcher EL. Pharmaceutical therapies targeting autophagy for the treatment of age-related macular degeneration. Curr Opin Pharmacol 2024; 76:102463. [PMID: 38788268 DOI: 10.1016/j.coph.2024.102463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 04/29/2024] [Accepted: 05/03/2024] [Indexed: 05/26/2024]
Abstract
Age-related macular degeneration (AMD) is a major cause of irreversible vision loss in the elderly. Although new therapies have recently emerged, there are currently no ways of preventing the development of the disease. Changes in intracellular recycling processes. Changes in intracellular recycling processes, called autophagy, lead to debris accumulation and cellular dysfunction in AMD models and AMD patients. Drugs that enhance autophagy hold promise as therapies for slowing AMD progression in preclinical models; however, more studies in humans are required. While a definitive cure for AMD will likely hinge on a personalized medicine approach, treatments that enhance autophagy hold promise for slowing vision loss.
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Affiliation(s)
- Kirstan A Vessey
- Department of Anatomy and Physiology, The University of Melbourne, VIC 3010, Australia; School of Science and Technology, The University of New England, NSW 2350, Australia
| | - Andrew I Jobling
- Department of Anatomy and Physiology, The University of Melbourne, VIC 3010, Australia
| | - Ursula Greferath
- Department of Anatomy and Physiology, The University of Melbourne, VIC 3010, Australia
| | - Erica L Fletcher
- Department of Anatomy and Physiology, The University of Melbourne, VIC 3010, Australia.
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2
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Bu LL, Yuan HH, Xie LL, Guo MH, Liao DF, Zheng XL. New Dawn for Atherosclerosis: Vascular Endothelial Cell Senescence and Death. Int J Mol Sci 2023; 24:15160. [PMID: 37894840 PMCID: PMC10606899 DOI: 10.3390/ijms242015160] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/01/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023] Open
Abstract
Endothelial cells (ECs) form the inner linings of blood vessels, and are directly exposed to endogenous hazard signals and metabolites in the circulatory system. The senescence and death of ECs are not only adverse outcomes, but also causal contributors to endothelial dysfunction, an early risk marker of atherosclerosis. The pathophysiological process of EC senescence involves both structural and functional changes and has been linked to various factors, including oxidative stress, dysregulated cell cycle, hyperuricemia, vascular inflammation, and aberrant metabolite sensing and signaling. Multiple forms of EC death have been documented in atherosclerosis, including autophagic cell death, apoptosis, pyroptosis, NETosis, necroptosis, and ferroptosis. Despite this, the molecular mechanisms underlying EC senescence or death in atherogenesis are not fully understood. To provide a comprehensive update on the subject, this review examines the historic and latest findings on the molecular mechanisms and functional alterations associated with EC senescence and death in different stages of atherosclerosis.
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Affiliation(s)
- Lan-Lan Bu
- School of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China; (L.-L.B.); (D.-F.L.)
| | - Huan-Huan Yuan
- College of Integrated Chinese and Western Medicine, Hunan University of Chinese Medicine, Changsha 410208, China; (H.-H.Y.); (L.-L.X.); (M.-H.G.)
| | - Ling-Li Xie
- College of Integrated Chinese and Western Medicine, Hunan University of Chinese Medicine, Changsha 410208, China; (H.-H.Y.); (L.-L.X.); (M.-H.G.)
- Departments of Biochemistry and Molecular Biology and Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Min-Hua Guo
- College of Integrated Chinese and Western Medicine, Hunan University of Chinese Medicine, Changsha 410208, China; (H.-H.Y.); (L.-L.X.); (M.-H.G.)
| | - Duan-Fang Liao
- School of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China; (L.-L.B.); (D.-F.L.)
| | - Xi-Long Zheng
- Departments of Biochemistry and Molecular Biology and Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
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Sharp ZD, Strong R. Rapamycin, the only drug that has been consistently demonstrated to increase mammalian longevity. An update. Exp Gerontol 2023; 176:112166. [PMID: 37011714 PMCID: PMC10868408 DOI: 10.1016/j.exger.2023.112166] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/30/2023] [Accepted: 03/31/2023] [Indexed: 04/05/2023]
Affiliation(s)
- Zelton Dave Sharp
- Department of Molecular Medicine and Institute of Biotechnology, San Antonio, TX, United States of America; Barshop Institute for Longevity and Aging Studies, San Antonio, TX, United States of America; Mays Cancer Center, San Antonio, TX, United States of America.
| | - Randy Strong
- Barshop Institute for Longevity and Aging Studies, San Antonio, TX, United States of America; Department of Pharmacology, UT Health, San Antonio, TX, United States of America; Research Service of the South Texas Veterans Health Care System, San Antonio, TX 78229, United States of America.
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4
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Zhang Y, Zhang J, Wang S. The Role of Rapamycin in Healthspan Extension via the Delay of Organ Aging. Ageing Res Rev 2021; 70:101376. [PMID: 34089901 DOI: 10.1016/j.arr.2021.101376] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 05/07/2021] [Accepted: 05/30/2021] [Indexed: 12/17/2022]
Abstract
Aging can not only shorten a healthy lifespan, but can also lead to multi-organ dysfunction and failure. Anti-aging is a complex and worldwide conundrum for eliminating the various pathologies of senility. The past decade has seen great progress in the understanding of the aging-associated signaling pathways and their application for developing anti-aging approaches. Currently, some drugs can improve quality of life. The activation of mammalian target of rapamycin (mTOR) signaling is one of the core and detrimental mechanisms related to aging; rapamycin can reduce the rate of aging, improve age-related diseases by inhibiting the mTOR pathway, and prolong lifespan and healthspan effectively. However, the current evidence for rapamycin in lifespan extension and organ aging is fragmented and scattered. In this review, we summarize the efficacy and safety of rapamycin in prolonging a healthy lifespan by systematically alleviating aging in multiple organ systems, i.e., the nervous, urinary, digestive, circulatory, motor, respiratory, endocrine, reproductive, integumentary and immune systems, to provide a theoretical basis for the future clinical application of rapamycin in anti-aging.
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Affiliation(s)
- Yan Zhang
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China; National Clinical Research Center for Obstetrical and Gynecological Diseases, Huazhong University of Science and Technology, Wuhan, 430030, China; Key Laboratory of Cancer Invasion and Metastasis, Ministry of Education, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jinjin Zhang
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China; National Clinical Research Center for Obstetrical and Gynecological Diseases, Huazhong University of Science and Technology, Wuhan, 430030, China; Key Laboratory of Cancer Invasion and Metastasis, Ministry of Education, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Shixuan Wang
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China; National Clinical Research Center for Obstetrical and Gynecological Diseases, Huazhong University of Science and Technology, Wuhan, 430030, China; Key Laboratory of Cancer Invasion and Metastasis, Ministry of Education, Huazhong University of Science and Technology, Wuhan, 430030, China.
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5
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Ding YN, Wang HY, Chen HZ, Liu DP. Targeting senescent cells for vascular aging and related diseases. J Mol Cell Cardiol 2021; 162:43-52. [PMID: 34437878 DOI: 10.1016/j.yjmcc.2021.08.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/08/2021] [Accepted: 08/17/2021] [Indexed: 01/10/2023]
Abstract
Cardiovascular diseases are a serious threat to human health, especially in the elderly. Vascular aging makes people more susceptible to cardiovascular diseases due to significant dysfunction or senescence of vascular cells and maladaptation of vascular structure and function; moreover, vascular aging is currently viewed as a modifiable cardiovascular risk factor. To emphasize the relationship between senescent cells and vascular aging, we first summarize the roles of senescent vascular cells (endothelial cells, smooth muscle cells and immune cells) in the vascular aging process and inducers that contribute to cellular senescence. Then, we present potential strategies for directly targeting senescent cells (senotherapy) or preventively targeting senescence inducers (senoprevention) to delay vascular aging and the development of age-related vascular diseases. Finally, based on recent research, we note some important questions that still need to be addressed in the future.
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Affiliation(s)
- Yang-Nan Ding
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, People's Republic of China
| | - Hui-Yu Wang
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, People's Republic of China
| | - Hou-Zao Chen
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, People's Republic of China.
| | - De-Pei Liu
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, People's Republic of China.
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6
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Norwitz NG, Querfurth H. mTOR Mysteries: Nuances and Questions About the Mechanistic Target of Rapamycin in Neurodegeneration. Front Neurosci 2020; 14:775. [PMID: 32903821 PMCID: PMC7438931 DOI: 10.3389/fnins.2020.00775] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 07/01/2020] [Indexed: 01/25/2023] Open
Abstract
The mechanistic target of rapamycin protein complex, mTORC1, has received attention in recent years for its role in aging and neurodegenerative diseases, such as Alzheimer's disease. Numerous excellent reviews have been written on the pathways and drug targeting of this keystone regulator of metabolism. However, none have specifically highlighted several important nuances of mTOR regulation as relates to neurodegeneration. Herein, we focus on six such nuances/open questions: (1) "Antagonistic pleiotropy" - Should we weigh the beneficial anabolic functions of mTORC1 against its harmful inhibition of autophagy? (2) "Early/late-stage specificity" - Does the relative importance of these neuroprotective/neurotoxic actions change as a disease progresses? (3) "Regional specificity" - Does mTOR signaling respond differently to the same interventions in different brain regions? (4) "Disease specificity" - Could the same intervention to inhibit mTORC1 help in one disease and cause harm in another disease? (5) "Personalized therapy" - Might genetically-informed personalized therapies that inhibit particular nodes in the mTORC1 regulatory network be more effective than generalized therapies? (6) "Lifestyle interventions" - Could specific diets, micronutrients, or exercise alter mTORC1 signaling to prevent or improve the progression neurodegenerative diseases? This manuscript is devoted to discussing recent research findings that offer insights into these gaps in the literature, with the aim of inspiring further inquiry.
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Affiliation(s)
- Nicholas G. Norwitz
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Henry Querfurth
- Department of Neurology, Tufts Medical Center, Boston, MA, United States
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7
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von Frieling J, Roeder T. Factors that affect the translation of dietary restriction into a longer life. IUBMB Life 2019; 72:814-824. [PMID: 31889425 DOI: 10.1002/iub.2224] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 12/20/2019] [Indexed: 02/06/2023]
Abstract
Nutritional interventions, such as dietary or calorie restriction, are known to have a variety of health-promoting effects. The most impressive are the direct effects on life expectancy, which have been reproduced in many animal models. A variety of dietary restriction protocols have been described, which differ either in their macronutrient composition or in the time window for consumption. Mechanistically, the effects of dietary restriction are mediated mainly through signaling pathways that have central roles in the maintenance of cellular energy balance. Among these, target of rapamycin and insulin signaling appear to be the most important. Such nutritional interventions can have their effects in two different ways: either by direct interaction with the metabolism of the host organism, or by modulating the composition and performance of its endogenous microbiome. Various dietary restriction regimens have been identified that significantly alter the microbiome and thus profoundly modulate host metabolism. This review aims to discuss the mechanisms by which dietary restriction can affect life expectancy, and in particular the role of the microbiome.
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Affiliation(s)
- Jakob von Frieling
- Department of Zoology, Molecular Physiology, Kiel University, Kiel, Germany
| | - Thomas Roeder
- Department of Zoology, Molecular Physiology, Kiel University, Kiel, Germany.,DZL, German Center for Lung Research, ARCN, Kiel, Germany
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8
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Liang H, Nie J, Van Skike CE, Valentine JM, Orr ME. Mammalian Target of Rapamycin at the Crossroad Between Alzheimer's Disease and Diabetes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1128:185-225. [PMID: 31062331 DOI: 10.1007/978-981-13-3540-2_10] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Accumulating evidence suggests that Alzheimer's disease may manifest as a metabolic disorder with pathology and/or dysfunction in numerous tissues. Adults with Alzheimer's disease suffer with significantly more comorbidities than demographically matched Medicare beneficiaries (Zhao et al, BMC Health Serv Res 8:108, 2008b). Reciprocally, comorbid health conditions increase the risk of developing Alzheimer's disease (Haaksma et al, PLoS One 12(5):e0177044, 2017). Type 2 diabetes mellitus is especially notable as the disease shares many overlapping pathologies observed in patients with Alzheimer's disease, including hyperglycemia, hyperinsulinemia, insulin resistance, glucose intolerance, dyslipidemia, inflammation, and cognitive dysfunction, as described in Chap. 8 of this book (Yoshitake et al, Neurology 45(6):1161-1168, 1995; Leibson et al, Am J Epidemiol 145(4):301-308, 1997; Ott et al, Neurology 53(9):1937-1942, 1999; Voisin et al, Rev Med Interne 24(Suppl 3):288s-291s, 2003; Janson et al. Diabetes 53(2):474-481, 2004; Ristow M, J Mol Med (Berl) 82(8):510-529, 2004; Whitmer et al, BMJ 330(7504):1360, 2005, Curr Alzheimer Res 4(2):103-109, 2007; Ohara et al, Neurology 77(12):1126-1134, 2011). Although nondiabetic older adults also experience age-related cognitive decline, diabetes is uniquely associated with a twofold increased risk of Alzheimer's disease, as described in Chap. 2 of this book (Yoshitake et al, Neurology 45(6):1161-1168, 1995; Leibson et al, Am J Epidemiol 145(4):301-308, 1997; Ott et al. Neurology 53(9):1937-1942, 1999; Ohara et al, Neurology 77(12):1126-1134, 2011). Good glycemic control has been shown to improve cognitive status (Cukierman-et al, Diabetes Care 32(2):221-226, 2009), and the use of insulin sensitizers is correlated with a lower rate of cognitive decline in older adults (Morris JK, Burns JM, Curr Neurol Neurosci Rep 12(5):520-527, 2012). At the molecular level, the mechanistic/mammalian target of rapamycin (mTOR) plays a key role in maintaining energy homeostasis. Nutrient availability and cellular stress information, both extracellular and intracellular, are integrated and transduced through mTOR signaling pathways. Aberrant regulation of mTOR occurs in the brains of patients with Alzheimer's disease and in numerous tissues of individuals with type 2 diabetes (Mannaa et al, J Mol Med (Berl) 91(10):1167-1175, 2013). Moreover, modulating mTOR activity with a pharmacological inhibitor, rapamycin, provides wide-ranging health benefits, including healthy life span extension in numerous model organisms (Vellai et al, Nature 426(6967):620, 2003; Jia et al, Development 131(16):3897-3906, 2004; Kapahi et al, Curr Biol 14(10):885-890, 2004; Kaeberlein et al, Science 310(5751):1193-1196, 2005; Powers et al, Genes Dev 20(2):174-184, 2006; Harrison et al, Nature 460(7253):392-395, 2009; Selman et al, Science 326(5949):140-144, 2009; Sharp ZD, Strong R, J Gerontol A Biol Sci Med Sci 65(6):580-589, 2010), which underscores its importance to overall organismal health and longevity. In this chapter, we discuss the physiological role of mTOR signaling and the consequences of mTOR dysregulation in the brain and peripheral tissues, with emphasis on its relevance to the development of Alzheimer's disease and link to type 2 diabetes.
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Affiliation(s)
- Hanyu Liang
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Jia Nie
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Candice E Van Skike
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Joseph M Valentine
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Miranda E Orr
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
- San Antonio Geriatric Research, Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, TX, USA.
- Glenn Biggs Institute for Alzheimer's & Neurodegenerative Diseases, San Antonio, TX, USA.
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Abstract
Advancing age promotes cardiovascular disease (CVD), the leading cause of death in the United States and many developed nations. Two major age-related arterial phenotypes, large elastic artery stiffening and endothelial dysfunction, are independent predictors of future CVD diagnosis and likely are responsible for the development of CVD in older adults. Not limited to traditional CVD, these age-related changes in the vasculature also contribute to other age-related diseases that influence mammalian health span and potential life span. This review explores mechanisms that influence age-related large elastic artery stiffening and endothelial dysfunction at the tissue level via inflammation and oxidative stress and at the cellular level via Klotho and energy-sensing pathways (AMPK [AMP-activated protein kinase], SIRT [sirtuins], and mTOR [mammalian target of rapamycin]). We also discuss how long-term calorie restriction-a health span- and life span-extending intervention-can prevent many of these age-related vascular phenotypes through the prevention of deleterious alterations in these mechanisms. Lastly, we discuss emerging novel mechanisms of vascular aging, including senescence and genomic instability within cells of the vasculature. As the population of older adults steadily expands, elucidating the cellular and molecular mechanisms of vascular dysfunction with age is critical to better direct appropriate and measured strategies that use pharmacological and lifestyle interventions to reduce risk of CVD within this population.
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Affiliation(s)
- Anthony J. Donato
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, Utah
- Veterans Affairs Medical Center-Salt Lake City, Geriatrics Research Education and Clinical Center, Salt Lake City, Utah
| | - Daniel R. Machin
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, Utah
- Veterans Affairs Medical Center-Salt Lake City, Geriatrics Research Education and Clinical Center, Salt Lake City, Utah
| | - Lisa A. Lesniewski
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, Utah
- Veterans Affairs Medical Center-Salt Lake City, Geriatrics Research Education and Clinical Center, Salt Lake City, Utah
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Gogulamudi VR, Cai J, Lesniewski LA. Reversing age-associated arterial dysfunction: insight from preclinical models. J Appl Physiol (1985) 2018; 125:1860-1870. [PMID: 29745797 DOI: 10.1152/japplphysiol.00086.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Cardiovascular diseases (CVDs) remain the leading causes of death in the United States, and advancing age is a primary risk factor. Impaired endothelium-dependent dilation and increased stiffening of the arteries with aging are independent predictors of CVD. Increased tissue and systemic oxidative stress and inflammation underlie this age-associated arterial dysfunction. Calorie restriction (CR) is the most powerful intervention known to increase life span and improve age-related phenotypes, including arterial dysfunction. However, the translatability of long-term CR to clinical populations is limited, stimulating interest in the pursuit of pharmacological CR mimetics to reproduce the beneficial effects of CR. The energy-sensing pathways, mammalian target of rapamycin, AMPK, and sirtuin-1 have all been implicated in the beneficial effects of CR on longevity and/or physiological function and, as such, have emerged as potential targets for therapeutic intervention as CR mimetics. Although manipulation of each of these pathways has CR-like benefits on arterial function, the magnitude and/or mechanisms can be disparate from that of CR. Nevertheless, targeting these pathways in older individuals may provide some benefits against arterial dysfunction and CVD. The goal of this review is to provide a brief discussion of the mechanisms and pathways underlying age-associated dysfunction in large arteries, explain how these are impacted by CR, and to present the available evidence, suggesting that targets for energy-sensing pathways may act as vascular CR mimetics.
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Affiliation(s)
| | - Jinjin Cai
- Department of Internal Medicine-Division of Geriatrics, University of Utah , Salt Lake City, Utah
| | - Lisa A Lesniewski
- Department of Internal Medicine-Division of Geriatrics, University of Utah , Salt Lake City, Utah.,Geriatrics Research Education and Clinical Center, Veteran's Affairs Medical Center-Salt Lake City, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
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11
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The effects of graded levels of calorie restriction: XI. Evaluation of the main hypotheses underpinning the life extension effects of CR using the hepatic transcriptome. Aging (Albany NY) 2018; 9:1770-1824. [PMID: 28768896 PMCID: PMC5559174 DOI: 10.18632/aging.101269] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 07/27/2017] [Indexed: 12/15/2022]
Abstract
Calorie restriction (CR) may extend longevity by modulating the mechanisms involved in aging. Different hypotheses have been proposed for its main mode of action. We quantified hepatic transcripts of male C57BL/6 mice exposed to graded levels of CR (0% to 40% CR) for three months, and evaluated the responses relative to these various hypotheses. Of the four main signaling pathways implied to be linked to the impact of CR on lifespan (insulin/insulin like growth factor 1 (IGF-1), nuclear factor-kappa beta (NF-ĸB), mechanistic target of rapamycin (mTOR) and sirtuins (SIRTs)), all the pathways except SIRT were altered in a manner consistent with increased lifespan. However, the expression levels of SIRT4 and SIRT7 were decreased with increasing levels of CR. Changes consistent with altered fuel utilization under CR may reduce reactive oxygen species production, which was paralleled by reduced protection. Downregulated major urinary protein (MUP) transcription suggested reduced reproductive investment. Graded CR had a positive effect on autophagy and xenobiotic metabolism, and was protective with respect to cancer signaling. CR had no significant effect on fibroblast growth factor-21 (FGF21) transcription but affected transcription in the hydrogen sulfide production pathway. Responses to CR were consistent with several different hypotheses, and the benefits of CR on lifespan likely reflect the combined impact on multiple aging related processes.
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12
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Franco R, Martínez-Pinilla E, Navarro G, Zamarbide M. Potential of GPCRs to modulate MAPK and mTOR pathways in Alzheimer's disease. Prog Neurobiol 2017; 149-150:21-38. [PMID: 28189739 DOI: 10.1016/j.pneurobio.2017.01.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 01/20/2017] [Accepted: 01/22/2017] [Indexed: 02/08/2023]
Abstract
Despite efforts to understand the mechanism of neuronal cell death, finding effective therapies for neurodegenerative diseases is still a challenge. Cognitive deficits are often associated with neurodegenerative diseases. Remarkably, in the absence of consensus biomarkers, diagnosis of diseases such as Alzheimer's still relies on cognitive tests. Unfortunately, all efforts to translate findings in animal models to the patients have been unsuccessful. Alzheimer's disease may be addressed from two different points of view, neuroprotection or cognitive enhancement. Based on recent data, the mammalian target of rapamycin (mTOR) pathway arises as a versatile player whose modulation may impact on mechanisms of both neuroprotection and cognition. Whereas direct targeting of mTOR does not seem to constitute a convenient approach in drug discovery, its indirect modulation by other signaling pathways seems promising. In fact, G-protein-coupled receptors (GPCRs) remain the most common 'druggable' targets and as such pharmacological manipulation of GPCRs with selective ligands may modulate phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), mitogen-activated protein (MAP) kinase and mTOR signaling pathways. Thus, GPCRs become important targets for potential drug treatments in different neurodegenerative disorders including, but not limited to, Alzheimer's disease. GPCR-mediated modulation of mTOR may take advantage of different GPCRs coupled to different G-dependent and G-independent signal transduction routes, of functional selectivity and/or of biased agonism. Signals mediated by GPCRs may act as coincidence detectors to achieve different benefits in different stages of the neurodegenerative disease.
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Affiliation(s)
- Rafael Franco
- Department of Biochemistry and Molecular Biomedicine and IBUB (Institute of Biomedicine of the University of Barcelona), University of Barcelona, Barcelona, Spain; Centro de investigación en Red: Enfermedades Neurodegenerativas, CIBERNED, Madrid, Spain
| | - Eva Martínez-Pinilla
- Instituto de Neurociencias del Principado de Asturias (INEUROPA), Departamento de Morfología y Biología Celular, Facultad de Medicina, Universidad de Oviedo, Asturias, Spain
| | - Gemma Navarro
- Department of Biochemistry and Molecular Biomedicine and IBUB (Institute of Biomedicine of the University of Barcelona), University of Barcelona, Barcelona, Spain; Centro de investigación en Red: Enfermedades Neurodegenerativas, CIBERNED, Madrid, Spain
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13
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An Update on Inflamm-Aging: Mechanisms, Prevention, and Treatment. J Immunol Res 2016; 2016:8426874. [PMID: 27493973 PMCID: PMC4963991 DOI: 10.1155/2016/8426874] [Citation(s) in RCA: 308] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/16/2016] [Accepted: 06/14/2016] [Indexed: 01/08/2023] Open
Abstract
Inflamm-aging is a challenging and promising new branch of aging-related research fields that includes areas such as immunosenescence. Increasing evidence indicates that inflamm-aging is intensively associated with many aging diseases, such as Alzheimer's disease, atherosclerosis, heart disease, type II diabetes, and cancer. Mounting studies have focused on the role of inflamm-aging in disease progression and many advances have been made in the last decade. However, the underlying mechanisms by which inflamm-aging affects pathological changes and disease development are still unclear. Here, we review studies of inflamm-aging that explore the concept, pathological features, mechanisms, intervention, and the therapeutic strategies of inflamm-aging in disease progression.
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Treuting PM, Snyder JM, Ikeno Y, Schofield PN, Ward JM, Sundberg JP. The Vital Role of Pathology in Improving Reproducibility and Translational Relevance of Aging Studies in Rodents. Vet Pathol 2016; 53:244-9. [PMID: 26792843 PMCID: PMC4835687 DOI: 10.1177/0300985815620629] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Pathology is a discipline of medicine that adds great benefit to aging studies of rodents by integrating in vivo, biochemical, and molecular data. It is not possible to diagnose systemic illness, comorbidities, and proximate causes of death in aging studies without the morphologic context provided by histopathology. To date, many rodent aging studies do not utilize end points supported by systematic necropsy and histopathology, which leaves studies incomplete, contradictory, and difficult to interpret. As in traditional toxicity studies, if the effect of a drug, dietary treatment, or altered gene expression on aging is to be studied, systematic pathology analysis must be included to determine the causes of age-related illness, moribundity, and death. In this Commentary, the authors discuss the factors that should be considered in the design of aging studies in mice, with the inclusion of robust pathology practices modified after those developed by toxicologic and discovery research pathologists. Investigators in the field of aging must consider the use of histopathology in their rodent aging studies in this era of integrative and preclinical geriatric science (geroscience).
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Affiliation(s)
- P M Treuting
- Department of Comparative Medicine, School of Medicine, University of Washington, Seattle, WA, USA
| | - J M Snyder
- Department of Comparative Medicine, School of Medicine, University of Washington, Seattle, WA, USA
| | - Y Ikeno
- Barshop Institute and Department of Pathology, University of Texas Health Science Center at San Antonio; Research Service and Geriatric Research and Education Clinical Center, Audie L. Murphy VA Hospital, South Texas Veterans Health Care System, San Antonio, TX, USA
| | - P N Schofield
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK The Jackson Laboratory, Bar Harbor, ME, USA
| | - J M Ward
- Global VetPathology, Montgomery Village, MD, USA
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15
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Donato AJ, Morgan RG, Walker AE, Lesniewski LA. Cellular and molecular biology of aging endothelial cells. J Mol Cell Cardiol 2015; 89:122-35. [PMID: 25655936 PMCID: PMC4522407 DOI: 10.1016/j.yjmcc.2015.01.021] [Citation(s) in RCA: 332] [Impact Index Per Article: 36.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 01/05/2015] [Accepted: 01/27/2015] [Indexed: 12/29/2022]
Abstract
Cardiovascular disease (CVD) is the leading cause of death in the United States and aging is a major risk factor for CVD development. One of the major age-related arterial phenotypes thought to be responsible for the development of CVD in older adults is endothelial dysfunction. Endothelial function is modulated by traditional CVD risk factors in young adults, but advancing age is independently associated with the development of vascular endothelial dysfunction. This endothelial dysfunction results from a reduction in nitric oxide bioavailability downstream of endothelial oxidative stress and inflammation that can be further modulated by traditional CVD risk factors in older adults. Greater endothelial oxidative stress with aging is a result of augmented production from the intracellular enzymes NADPH oxidase and uncoupled eNOS, as well as from mitochondrial respiration in the absence of appropriate increases in antioxidant defenses as regulated by relevant transcription factors, such as FOXO. Interestingly, it appears that NFkB, a critical inflammatory transcription factor, is sensitive to this age-related endothelial redox change and its activation induces transcription of pro-inflammatory cytokines that can further suppress endothelial function, thus creating a vicious feed-forward cycle. This review will discuss the two macro-mechanistic processes, oxidative stress and inflammation, that contribute to endothelial dysfunction with advancing age as well as the cellular and molecular events that lead to the vicious cycle of inflammation and oxidative stress in the aged endothelium. Other potential mediators of this pro-inflammatory endothelial phenotype are increases in immune or senescent cells in the vasculature. Of note, genomic instability, telomere dysfunction or DNA damage has been shown to trigger cell senescence via the p53/p21 pathway and result in increased inflammatory signaling in arteries from older adults. This review will discuss the current state of knowledge regarding the emerging concepts of senescence and genomic instability as mechanisms underlying oxidative stress and inflammation in the aged endothelium. Lastly, energy sensitive/stress resistance pathways (SIRT-1, AMPK, mTOR) are altered in endothelial cells and/or arteries with aging and these pathways may modulate endothelial function via key oxidative stress and inflammation-related transcription factors. This review will also discuss what is known about the role of "energy sensing" longevity pathways in modulating endothelial function with advancing age. With the growing population of older adults, elucidating the cellular and molecular mechanisms of endothelial dysfunction with age is critical to establishing appropriate and measured strategies to utilize pharmacological and lifestyle interventions aimed at alleviating CVD risk. This article is part of a Special Issue entitled "SI: CV Aging".
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Affiliation(s)
- Anthony J Donato
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, UT, USA; Veteran's Affairs Medical Center-Salt Lake City, Geriatrics Research Education and Clinical Center, Salt Lake City, UT, USA.
| | - R Garrett Morgan
- University of Washington, Department of Pathology, Seattle, WA, USA
| | - Ashley E Walker
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, UT, USA
| | - Lisa A Lesniewski
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, UT, USA; Veteran's Affairs Medical Center-Salt Lake City, Geriatrics Research Education and Clinical Center, Salt Lake City, UT, USA
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16
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Bai X, Wey MCY, Fernandez E, Hart MJ, Gelfond J, Bokov AF, Rani S, Strong R. Rapamycin improves motor function, reduces 4-hydroxynonenal adducted protein in brain, and attenuates synaptic injury in a mouse model of synucleinopathy. PATHOBIOLOGY OF AGING & AGE RELATED DISEASES 2015; 5:28743. [PMID: 26306821 PMCID: PMC4549373 DOI: 10.3402/pba.v5.28743] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 07/03/2015] [Accepted: 07/03/2015] [Indexed: 11/15/2022]
Abstract
BACKGROUND Synucleinopathy is any of a group of age-related neurodegenerative disorders including Parkinson's disease, multiple system atrophy, and dementia with Lewy Bodies, which is characterized by α-synuclein inclusions and parkinsonian motor deficits affecting millions of patients worldwide. But there is no cure at present for synucleinopathy. Rapamycin has been shown to be neuroprotective in several in vitro and in vivo synucleinopathy models. However, there are no reports on the long-term effects of RAPA on motor function or measures of neurodegeneration in models of synucleinopathy. METHODS We determined whether long-term feeding a rapamycin diet (14 ppm in diet; 2.25 mg/kg body weight/day) improves motor function in neuronal A53T α-synuclein transgenic mice (TG) and explored underlying mechanisms using a variety of behavioral and biochemical approaches. RESULTS After 24 weeks of treatment, rapamycin improved performance on the forepaw stepping adjustment test, accelerating rotarod and pole test. Rapamycin did not alter A53T α-synuclein content. There was no effect of rapamycin treatment on midbrain or striatal monoamines or their metabolites. Proteins adducted to the lipid peroxidation product 4-hydroxynonenal were decreased in brain regions of both wild-type and TG mice treated with rapamycin. Reduced levels of the presynaptic marker synaptophysin were found in several brain regions of TG mice. Rapamycin attenuated the loss of synaptophysin protein in the affected brain regions. Rapamycin also attenuated the loss of synaptophysin protein and prevented the decrease of neurite length in SH-SY5Y cells treated with 4-hydroxynonenal. CONCLUSION Taken together, these data suggest that rapamycin, an FDA approved drug, may prove useful in the treatment of synucleinopathy.
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Affiliation(s)
- Xiang Bai
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Margaret Chia-Ying Wey
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Elizabeth Fernandez
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Geriatric Research, Education and Clinical Center, South Texas Veterans Health Care Network, San Antonio, TX, USA
| | - Matthew J Hart
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Department of Biochemistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- High Throughput Screening Facility, Center for Innovative Drug Discovery University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Jonathan Gelfond
- Department of Epidemiology & Biostatistics, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Alex F Bokov
- Department of Epidemiology & Biostatistics, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Sheela Rani
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Randy Strong
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Geriatric Research, Education and Clinical Center, South Texas Veterans Health Care Network, San Antonio, TX, USA;
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Warner HR. NIA's Intervention Testing Program at 10 years of age. AGE (DORDRECHT, NETHERLANDS) 2015; 37:22. [PMID: 25726185 PMCID: PMC4344944 DOI: 10.1007/s11357-015-9761-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 02/18/2015] [Indexed: 06/04/2023]
Abstract
The previous 20 years of basic research on aging has identified a large number of genes and gene products whose expression can be manipulated in a variety of ways to increase the healthy life span of animal models such as yeast, nematodes, fruit flies, and mice. In an overt attempt to capitalize on this information, the National Institute on Aging (NIA) began a program in 2003 to identify nutritional and pharmaceutical interventions that could be safely employed to extend the healthy life span of mice. This program is called the Intervention Testing Program (ITP), and this article briefly describes the development of this initiative and some of the early success achieved during its first 10 years (2004-2014) of operation.
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Affiliation(s)
- Huber R Warner
- College of Biological Sciences, University of Minnesota, St. Paul, MN, 55108, USA,
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18
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Tardif S, Ross C, Bergman P, Fernandez E, Javors M, Salmon A, Spross J, Strong R, Richardson A. Testing efficacy of administration of the antiaging drug rapamycin in a nonhuman primate, the common marmoset. J Gerontol A Biol Sci Med Sci 2014; 70:577-87. [PMID: 25038772 DOI: 10.1093/gerona/glu101] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 06/02/2014] [Indexed: 11/13/2022] Open
Abstract
This report is the first description of dosing procedures, pharmacokinetics, biochemical action, and general tolerability of the antiaging drug rapamycin in the common marmoset, a small and short-lived monkey. Eudragit-encapsulated rapamycin was given orally to trained marmosets in a short-term (3 weeks) and a long-term (14 months) study. Circulating trough rapamycin levels (mean = 5.2 ng/mL; 1.93-10.73 ng/mL) achieved at roughly 1.0 mg/kg/day was comparable to those reported in studies of rodents and within the therapeutic range for humans. Long-term treated animals (6/8) indicated a reduction in mammalian target of rapamycin complex 1 signaling as noted by a decrease in the phospho rpS6 to total rpS6 ratio after 2 weeks of treatment. All long-term treated subjects had detectable concentrations of rapamycin in liver (4.7-19.9 pg/mg) and adipose tissue (2.2-32.8 pg/mg) with reduced mammalian target of rapamycin signaling in these tissues. There was no evidence of clinical anemia, fibrotic lung changes, or mouth ulcers. The observed death rate in the long-term study was as expected given the animals' ages. The ability to rapidly and reliably dose socially housed marmosets with an oral form of rapamycin that is well tolerated and that demonstrates a suppression of the mammalian target of rapamycin pathway leads us to conclude that this species offers a viable model for rapamycin testing to establish safety and efficacy for long-term antiaging intervention.
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Affiliation(s)
- Suzette Tardif
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center San Antonio. Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio.
| | - Corinna Ross
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center San Antonio. Department of Arts & Sciences, Texas A&M-San Antonio
| | - Phillip Bergman
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center San Antonio
| | - Elizabeth Fernandez
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center San Antonio. Geriatric Research, Education and Clinical Center, South Texas Veteran's Health Care System, San Antonio
| | - Marty Javors
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center San Antonio
| | - Adam Salmon
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center San Antonio. Geriatric Research, Education and Clinical Center, South Texas Veteran's Health Care System, San Antonio
| | - Jennifer Spross
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center San Antonio
| | - Randy Strong
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center San Antonio. Department of Arts & Sciences, Texas A&M-San Antonio
| | - Arlan Richardson
- University of Oklahoma Health Sciences Center and the Oklahoma City VA Medical Center
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Chung K, Kim D, Park M, Choi Y, Kim N, Lee J, Yu B, Chung H. Recent advances in calorie restriction research on aging. Exp Gerontol 2013. [DOI: 10.1016/j.exger.2012.11.007] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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20
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Bowers J, Terrien J, Clerget-Froidevaux MS, Gothié JD, Rozing MP, Westendorp RGJ, van Heemst D, Demeneix BA. Thyroid hormone signaling and homeostasis during aging. Endocr Rev 2013; 34:556-89. [PMID: 23696256 DOI: 10.1210/er.2012-1056] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Studies in humans and in animal models show negative correlations between thyroid hormone (TH) levels and longevity. TH signaling is implicated in maintaining and integrating metabolic homeostasis at multiple levels, notably centrally in the hypothalamus but also in peripheral tissues. The question is thus raised of how TH signaling is modulated during aging in different tissues. Classically, TH actions on mitochondria and heat production are obvious candidates to link negative effects of TH to aging. Mitochondrial effects of excess TH include reactive oxygen species and DNA damage, 2 factors often considered as aging accelerators. Inversely, caloric restriction, which can retard aging from nematodes to primates, causes a rapid reduction of circulating TH, reducing metabolism in birds and mammals. However, many other factors could link TH to aging, and it is these potentially subtler and less explored areas that are highlighted here. For example, effects of TH on membrane composition, inflammatory responses, stem cell renewal and synchronization of physiological responses to light could each contribute to TH regulation of maintenance of homeostasis during aging. We propose the hypothesis that constraints on TH signaling at certain life stages, notably during maturity, are advantageous for optimal aging.
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Affiliation(s)
- J Bowers
- Muséum national d'Histoire Naturelle, Laboratoire de Physiologie Générale et Comparée, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 7221, 75231 Paris cedex 5, France
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21
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Fletcher L, Evans TM, Watts LT, Jimenez DF, Digicaylioglu M. Rapamycin treatment improves neuron viability in an in vitro model of stroke. PLoS One 2013; 8:e68281. [PMID: 23861877 PMCID: PMC3701663 DOI: 10.1371/journal.pone.0068281] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 05/28/2013] [Indexed: 12/22/2022] Open
Abstract
Ischemic stroke is the leading cause of serious, long-term adult disability and is associated with sensorimotor and cognitive impairments due to neuronal degeneration. Currently, recombinant tissue plasminogen activator (rTPA) is the only FDA-approved medical therapy for treatment of patients with acute ischemic stroke. However, rTPA can only be given within 3 hours of symptom onset, and only 2% of patients are eligible. Therefore, there is an urgent need for novel neuroprotective treatment options for ischemic stroke. An emerging treatment for a diverse range of neurological disorders associated with neurodegeneration is rapamycin, a key modulator of the mammalian target of rapamycin (mTOR) pathway. The mTOR pathway is the primary regulator of the cellular response to nutrient availability, changes in energy status and stress as seen following ischemia and reperfusion. However, rapamycin’s effects on mTORC1 and mTORC2 are poorly understood in neurons. In the current study we show that rapamycin can prevent the activation of both mTORC1 and mTORC2 in cortical neurons and improve cell survival following oxygen glucose deprivation (OGD), an in vitro model of ischemic stroke. This work further supports the investigation of rapamycin as a novel neuroprotectant for ischemic stroke.
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Affiliation(s)
- Lauren Fletcher
- Department of Neurosurgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Teresa M. Evans
- Department of Neurosurgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Lora Talley Watts
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - David F. Jimenez
- Department of Neurosurgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Murat Digicaylioglu
- Department of Neurosurgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- * E-mail:
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22
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Collino S, Montoliu I, Martin FPJ, Scherer M, Mari D, Salvioli S, Bucci L, Ostan R, Monti D, Biagi E, Brigidi P, Franceschi C, Rezzi S. Metabolic signatures of extreme longevity in northern Italian centenarians reveal a complex remodeling of lipids, amino acids, and gut microbiota metabolism. PLoS One 2013; 8:e56564. [PMID: 23483888 PMCID: PMC3590212 DOI: 10.1371/journal.pone.0056564 10.1371/annotation/5fb9fa6f-4889-4407-8430-6dfc7ecdfbdd] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The aging phenotype in humans has been thoroughly studied but a detailed metabolic profiling capable of shading light on the underpinning biological processes of longevity is still missing. Here using a combined metabonomics approach compromising holistic (1)H-NMR profiling and targeted MS approaches, we report for the first time the metabolic phenotype of longevity in a well characterized human aging cohort compromising mostly female centenarians, elderly, and young individuals. With increasing age, targeted MS profiling of blood serum displayed a marked decrease in tryptophan concentration, while an unique alteration of specific glycerophospholipids and sphingolipids are seen in the longevity phenotype. We hypothesized that the overall lipidome changes specific to longevity putatively reflect centenarians' unique capacity to adapt/respond to the accumulating oxidative and chronic inflammatory conditions characteristic of their extreme aging phenotype. Our data in centenarians support promotion of cellular detoxification mechanisms through specific modulation of the arachidonic acid metabolic cascade as we underpinned increased concentration of 8,9-EpETrE, suggesting enhanced cytochrome P450 (CYP) enzyme activity. Such effective mechanism might result in the activation of an anti-oxidative response, as displayed by decreased circulating levels of 9-HODE and 9-oxoODE, markers of lipid peroxidation and oxidative products of linoleic acid. Lastly, we also revealed that the longevity process deeply affects the structure and composition of the human gut microbiota as shown by the increased extrection of phenylacetylglutamine (PAG) and p-cresol sulfate (PCS) in urine of centenarians. Together, our novel approach in this representative Italian longevity cohort support the hypothesis that a complex remodeling of lipid, amino acid metabolism, and of gut microbiota functionality are key regulatory processes marking exceptional longevity in humans.
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Affiliation(s)
- Sebastiano Collino
- Proteomics and Metabonomics, Nestlé Institute of Health Sciences SA, Campus EPFL, Quartier de l'innovation, Lausanne, Switzerland.
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23
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Collino S, Montoliu I, Martin FPJ, Scherer M, Mari D, Salvioli S, Bucci L, Ostan R, Monti D, Biagi E, Brigidi P, Franceschi C, Rezzi S. Metabolic signatures of extreme longevity in northern Italian centenarians reveal a complex remodeling of lipids, amino acids, and gut microbiota metabolism. PLoS One 2013; 8:e56564. [PMID: 23483888 PMCID: PMC3590212 DOI: 10.1371/journal.pone.0056564] [Citation(s) in RCA: 165] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 01/11/2013] [Indexed: 12/14/2022] Open
Abstract
The aging phenotype in humans has been thoroughly studied but a detailed metabolic profiling capable of shading light on the underpinning biological processes of longevity is still missing. Here using a combined metabonomics approach compromising holistic 1H-NMR profiling and targeted MS approaches, we report for the first time the metabolic phenotype of longevity in a well characterized human aging cohort compromising mostly female centenarians, elderly, and young individuals. With increasing age, targeted MS profiling of blood serum displayed a marked decrease in tryptophan concentration, while an unique alteration of specific glycerophospholipids and sphingolipids are seen in the longevity phenotype. We hypothesized that the overall lipidome changes specific to longevity putatively reflect centenarians' unique capacity to adapt/respond to the accumulating oxidative and chronic inflammatory conditions characteristic of their extreme aging phenotype. Our data in centenarians support promotion of cellular detoxification mechanisms through specific modulation of the arachidonic acid metabolic cascade as we underpinned increased concentration of 8,9-EpETrE, suggesting enhanced cytochrome P450 (CYP) enzyme activity. Such effective mechanism might result in the activation of an anti-oxidative response, as displayed by decreased circulating levels of 9-HODE and 9-oxoODE, markers of lipid peroxidation and oxidative products of linoleic acid. Lastly, we also revealed that the longevity process deeply affects the structure and composition of the human gut microbiota as shown by the increased extrection of phenylacetylglutamine (PAG) and p-cresol sulfate (PCS) in urine of centenarians. Together, our novel approach in this representative Italian longevity cohort support the hypothesis that a complex remodeling of lipid, amino acid metabolism, and of gut microbiota functionality are key regulatory processes marking exceptional longevity in humans.
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Affiliation(s)
- Sebastiano Collino
- Proteomics and Metabonomics, Nestlé Institute of Health Sciences SA, Campus EPFL, Quartier de l'innovation, Lausanne, Switzerland.
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24
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Jiang J, Feng L, Liu Y, Jiang WD, Hu K, Li SH, Zhou XQ. Mechanistic target of rapamycin in common carp: cDNA cloning, characterization, and tissue expression. Gene 2013; 512:566-72. [DOI: 10.1016/j.gene.2012.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Revised: 07/04/2012] [Accepted: 08/02/2012] [Indexed: 01/13/2023]
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25
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The mouse as a model organism in aging research: usefulness, pitfalls and possibilities. Ageing Res Rev 2013; 12:8-21. [PMID: 22543101 DOI: 10.1016/j.arr.2012.03.010] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 03/20/2012] [Accepted: 03/30/2012] [Indexed: 12/29/2022]
Abstract
The mouse has become the favorite mammalian model. Among the many reasons for this privileged position of mice is their genetic proximity to humans, the possibilities of genetically manipulating their genomes and the availability of many tools, mutants and inbred strains. Also in the field of aging, mice have become very robust and reliable research tools. Since laboratory mice have a life expectancy of only a few years, genetic approaches and other strategies for intervening in aging can be tested by examining their effects on life span and aging parameters during the relatively short period of, for example, a PhD project. Moreover, experiments on mice with an extended life span as well as on mice demonstrating signs of (segmental) premature aging, together with genetic mapping strategies, have provided novel insights into the fundamental processes that drive aging. Finally, the results of studies on caloric restriction and pharmacological anti-aging treatments in mice have a high degree of relevance to humans. In this paper, we review a number of recent genetic mapping studies that have yielded novel insights into the aging process. We discuss the value of the mouse as a model for testing interventions in aging, such as caloric restriction, and we critically discuss mouse strains with an extended or a shortened life span as models of aging.
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26
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Sharma N, Castorena CM, Cartee GD. Tissue-specific responses of IGF-1/insulin and mTOR signaling in calorie restricted rats. PLoS One 2012; 7:e38835. [PMID: 22701721 PMCID: PMC3368930 DOI: 10.1371/journal.pone.0038835] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 05/15/2012] [Indexed: 12/22/2022] Open
Abstract
Moderate calorie restriction (CR) (∼60% of ad libitum, AL, intake) has been associated with numerous favorable physiological outcomes in many species, and the insulin/IGF-1 and mTOR signaling pathways have each been proposed as potential mediators for many of CR's bioeffects. However, few studies have assessed the widely held idea that CR induces the down-regulation of the insulin/IGF-1 and/or mTOR pathways in multiple tissues. Accordingly, we analyzed the phosphorylation status of 11 key signaling proteins from the insulin/IGF-1 (IRTyr1162/1163, IGF-1RTyr1135/1136, IRS-1Ser312, PTENSer380, AktSer473, GSK3αSer21, GSK3βSer9) and mTOR (TSC2Ser939, mTORSer2448, P70S6KThr412, RPS6Ser235/236) pathways in 11 diverse tissues [liver, kidney, lung, aorta, two brain regions (cortex and cerebellum), and two slow-twitch and three fast-twitch skeletal muscles] from 9-month-old male AL and CR Fischer 344 x Brown Norway rats. The rats were studied under two conditions: with endogenous insulin levels (i.e., AL>CR) and with insulin infused during a hyperinsulinemic-euglycemic clamp so that plasma insulin concentrations were matched between the two diet groups. The most striking and consistent effect of CR was greater pAkt in 3 of the 5 skeletal muscles of CR vs. AL rats. There were no significant CR effects on the mTOR signaling pathway and no evidence that CR caused a general attenuation of mTOR signaling across the tissues studied. Rather than supporting the premise of a global downregulation of insulin/IGF-1 and/or mTOR signaling in many tissues, the current results revealed clear tissue-specific CR effects for the insulin signaling pathway without CR effects on the mTOR signaling pathway.
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Affiliation(s)
- Naveen Sharma
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Carlos M. Castorena
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Gregory D. Cartee
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
- Institute of Gerontology, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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27
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Fok WC, Zhang Y, Salmon AB, Bhattacharya A, Gunda R, Jones D, Ward W, Fisher K, Richardson A, Pérez VI. Short-term treatment with rapamycin and dietary restriction have overlapping and distinctive effects in young mice. J Gerontol A Biol Sci Med Sci 2012; 68:108-16. [PMID: 22570137 PMCID: PMC3598360 DOI: 10.1093/gerona/gls127] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Because rapamycin, an inhibitor of the nutrient sensor mammalian target of rapamycin, and dietary restriction both increase life span of mice, it has been hypothesized that they act through similar mechanisms. To test this hypothesis, we compared various biological parameters in dietary restriction mice (40% food restriction) and mice fed rapamycin (14 ppm). Both treatments led to a significant reduction in mammalian target of rapamycin signaling and a corresponding increase in autophagy. However, we observed striking differences in fat mass, insulin sensitivity, and expression of cell cycle and sirtuin genes in mice fed rapamycin compared with dietary restriction. Thus, although both treatments lead to significant downregulation of mammalian target of rapamycin signaling, these two manipulations have quite different effects on other physiological functions suggesting that they might increase life span through a common pathway as well as pathways that are altered differently by dietary restriction and rapamycin.
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Affiliation(s)
- Wilson C Fok
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, Texas, USA
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Majumder S, Caccamo A, Medina DX, Benavides AD, Javors MA, Kraig E, Strong R, Richardson A, Oddo S. Lifelong rapamycin administration ameliorates age-dependent cognitive deficits by reducing IL-1β and enhancing NMDA signaling. Aging Cell 2012; 11:326-35. [PMID: 22212527 DOI: 10.1111/j.1474-9726.2011.00791.x] [Citation(s) in RCA: 162] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Understanding the factors that contribute to age-related cognitive decline is imperative, particularly as age is the major risk factor for several neurodegenerative disorders. Levels of several cytokines increase in the brain during aging, including IL-1β, whose levels positively correlate with cognitive deficits. Previous reports show that reducing the activity of the mammalian target of rapamycin (mTOR) extends lifespan in yeast, nematodes, Drosophila, and mice. It remains to be established, however, whether extending lifespan with rapamycin is accompanied by an improvement in cognitive function. In this study, we show that 18-month-old mice treated with rapamycin starting at 2 months of age perform significantly better on a task measuring spatial learning and memory compared to age-matched mice on the control diet. In contrast, rapamycin does not improve cognition when given to 15-month-old mice with pre-existing, age-dependent learning and memory deficits. We further show that the rapamycin-mediated improvement in learning and memory is associated with a decrease in IL-1β levels and an increase in NMDA signaling. This is the first evidence to show that a small molecule known to increase lifespan also ameliorates age-dependent learning and memory deficits.
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Affiliation(s)
- Smita Majumder
- Department of Physiology, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
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29
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Abstract
Abstract Geroprotectors are drugs that decrease the rate of aging and therefore extend life span. Metformin has been described as a geroprotector, and several studies have shown that metformin can slow down the rate of aging. The mechanisms behind the geroprotective effect of metformin are less established. The goal of this review is to investigate the evidence for the geroprotective effect of metformin and to describe the possible mechanisms behind it.
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30
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Abstract
Genetic down-regulation of a major nutrient-sensing pathway, TOR (target of rapamycin) signalling, can improve health and extend lifespan in evolutionarily distant organisms such as yeast and mammals. Recently, it has been demonstrated that treatment with a pharmacological inhibitor of the TOR pathway, rapamycin, can replicate those findings and improve aging in a variety of model organisms. The proposed underlying anti-aging mechanisms are down-regulated translation, increased autophagy, altered metabolism and increased stress resistance.
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31
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Aging and cancer: can mTOR inhibitors kill two birds with one drug? Target Oncol 2011; 6:41-51. [DOI: 10.1007/s11523-011-0168-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 02/16/2011] [Indexed: 01/01/2023]
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Sharp ZD. Aging and TOR: interwoven in the fabric of life. Cell Mol Life Sci 2011; 68:587-97. [PMID: 20960025 PMCID: PMC11114916 DOI: 10.1007/s00018-010-0542-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 09/22/2010] [Accepted: 09/27/2010] [Indexed: 10/18/2022]
Abstract
Longstanding results with calorie and growth factor restriction plus recent results with the first interventional drug suggest that retarding the pace of aging to improve the quality of life of older people is at hand. The biological system targeted by these approaches is the target of rapamycin (TOR), which is central for cellular responses to a variety of stimuli including stressors, growth factors, and nutrients and energy states. That the life-extending response to reducing its activity is highly conserved from yeast to mammals is consistent with the evolution of aging as a strategy to preserve reproductive potential of young cells and animals.
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Affiliation(s)
- Zelton Dave Sharp
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center San Antonio, San Antonio, TX, 78245, USA.
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Giovannelli L, Pitozzi V, Jacomelli M, Mulinacci N, Laurenzana A, Dolara P, Mocali A. Protective Effects of Resveratrol Against Senescence-Associated Changes in Cultured Human Fibroblasts. ACTA ACUST UNITED AC 2010; 66:9-18. [DOI: 10.1093/gerona/glq161] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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34
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Foster KG, Fingar DC. Mammalian target of rapamycin (mTOR): conducting the cellular signaling symphony. J Biol Chem 2010; 285:14071-7. [PMID: 20231296 DOI: 10.1074/jbc.r109.094003] [Citation(s) in RCA: 394] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The mammalian target of rapamycin (mTOR) protein kinase responds to diverse environmental cues to control a plethora of cellular processes. mTOR forms the catalytic core of at least two distinct signaling complexes known as mTOR complexes 1 and 2. Differing sensitivities to the mTOR inhibitor rapamycin, unique partner proteins, distinct substrates, and unique cellular functions distinguish the complexes. Here, we review recent progress in our understanding of the regulation and function of mTOR signaling networks in cellular physiology.
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Affiliation(s)
- Kathryn G Foster
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan 48109-2200, USA
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