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Rae CD, Baur JA, Borges K, Dienel G, Díaz-García CM, Douglass SR, Drew K, Duarte JMN, Duran J, Kann O, Kristian T, Lee-Liu D, Lindquist BE, McNay EC, Robinson MB, Rothman DL, Rowlands BD, Ryan TA, Scafidi J, Scafidi S, Shuttleworth CW, Swanson RA, Uruk G, Vardjan N, Zorec R, McKenna MC. Brain energy metabolism: A roadmap for future research. J Neurochem 2024; 168:910-954. [PMID: 38183680 PMCID: PMC11102343 DOI: 10.1111/jnc.16032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 11/29/2023] [Accepted: 12/05/2023] [Indexed: 01/08/2024]
Abstract
Although we have learned much about how the brain fuels its functions over the last decades, there remains much still to discover in an organ that is so complex. This article lays out major gaps in our knowledge of interrelationships between brain metabolism and brain function, including biochemical, cellular, and subcellular aspects of functional metabolism and its imaging in adult brain, as well as during development, aging, and disease. The focus is on unknowns in metabolism of major brain substrates and associated transporters, the roles of insulin and of lipid droplets, the emerging role of metabolism in microglia, mysteries about the major brain cofactor and signaling molecule NAD+, as well as unsolved problems underlying brain metabolism in pathologies such as traumatic brain injury, epilepsy, and metabolic downregulation during hibernation. It describes our current level of understanding of these facets of brain energy metabolism as well as a roadmap for future research.
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Affiliation(s)
- Caroline D. Rae
- School of Psychology, The University of New South Wales, NSW 2052 & Neuroscience Research Australia, Randwick, New South Wales, Australia
| | - Joseph A. Baur
- Department of Physiology and Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Karin Borges
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia
| | - Gerald Dienel
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Department of Cell Biology and Physiology, University of New Mexico School of Medicine, Albuquerque, New Mexico, USA
| | - Carlos Manlio Díaz-García
- Department of Biochemistry and Molecular Biology, Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | | | - Kelly Drew
- Center for Transformative Research in Metabolism, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - João M. N. Duarte
- Department of Experimental Medical Science, Faculty of Medicine, Lund University, Lund, & Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Jordi Duran
- Institut Químic de Sarrià (IQS), Universitat Ramon Llull (URL), Barcelona, Spain
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120; Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
| | - Tibor Kristian
- Veterans Affairs Maryland Health Center System, Baltimore, Maryland, USA
- Department of Anesthesiology and the Center for Shock, Trauma, and Anesthesiology Research (S.T.A.R.), University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dasfne Lee-Liu
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Región Metropolitana, Chile
| | - Britta E. Lindquist
- Department of Neurology, Division of Neurocritical Care, Gladstone Institute of Neurological Disease, University of California at San Francisco, San Francisco, California, USA
| | - Ewan C. McNay
- Behavioral Neuroscience, University at Albany, Albany, New York, USA
| | - Michael B. Robinson
- Departments of Pediatrics and System Pharmacology & Translational Therapeutics, Children’s Hospital of Philadelphia, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Douglas L. Rothman
- Magnetic Resonance Research Center and Departments of Radiology and Biomedical Engineering, Yale University, New Haven, Connecticut, USA
| | - Benjamin D. Rowlands
- School of Chemistry, Faculty of Science, The University of Sydney, Sydney, New South Wales, Australia
| | - Timothy A. Ryan
- Department of Biochemistry, Weill Cornell Medicine, New York, New York, USA
| | - Joseph Scafidi
- Department of Neurology, Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Susanna Scafidi
- Anesthesiology & Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - C. William Shuttleworth
- Department of Neurosciences, University of New Mexico School of Medicine Albuquerque, Albuquerque, New Mexico, USA
| | - Raymond A. Swanson
- Department of Neurology, University of California, San Francisco, and San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
| | - Gökhan Uruk
- Department of Neurology, University of California, San Francisco, and San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
| | - Nina Vardjan
- Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
- Laboratory of Neuroendocrinology—Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Robert Zorec
- Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
- Laboratory of Neuroendocrinology—Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Mary C. McKenna
- Department of Pediatrics and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Wilson NE, Elliott MA, Nanga RPR, Swago S, Witschey WR, Reddy R. Optimization of 1H MR spectroscopy methods for large volume acquisition of low concentration downfield resonances at 3T and 7T. medRxiv 2024:2024.04.09.24305552. [PMID: 38645233 PMCID: PMC11030301 DOI: 10.1101/2024.04.09.24305552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Purpose This goal of this study was to optimize spectrally selective 1H MRS methods for large volume acquisition of low concentration metabolites with downfield resonances at 7T and 3T, with particular attention paid to detection of nicotinamide adenine dinucleotide (NAD+) and tryptophan. Methods Spectrally selective excitation was used to avoid magnetization transfer effects with water, and various sinc pulses were compared to a pure-phase E-BURP pulse. Localization using a single slice selective pulse was compared to voxel-based localization that used three orthogonal refocusing pulses, and low bandwidth refocusing pulses were used to take advantage of the chemical shift displacement of water. A technique for water sideband removal was added, and a method of coil channel combination for large volumes was introduced. Results Proposed methods were compared qualitatively to previously-reported techniques at 7T. Sinc pulses resulted in reduced water signal excitation and improved spectral quality, with a symmetric, low bandwidth-time product pulse performing best. Single slice localization allowed shorter TEs with large volumes, enhancing signal, while low bandwidth slice selective localization greatly reduced the observed water signal. Gradient cycling helped remove water sidebands, and frequency aligning and pruning individual channels narrowed spectral linewidths. High quality brain spectra of NAD+ and tryptophan are shown in four subjects at 3T. Conclusion Improved spectral quality with higher downfield signal, shorter TE, lower nuisance signal, reduced artifacts, and narrower peaks was realized at 7T. These methodological improvements allowed for previously unachievable detection of NAD+ and tryptophan in human brain at 3T in under five minutes.
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Affiliation(s)
- Neil E. Wilson
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Mark A. Elliott
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ravi Prakash Reddy Nanga
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sophia Swago
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, USA
| | - Walter R. Witschey
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ravinder Reddy
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Iqbal T, Nakagawa T. The therapeutic perspective of NAD + precursors in age-related diseases. Biochem Biophys Res Commun 2024; 702:149590. [PMID: 38340651 DOI: 10.1016/j.bbrc.2024.149590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 01/18/2024] [Accepted: 01/25/2024] [Indexed: 02/12/2024]
Abstract
Nicotinamide adenine dinucleotide (NAD+) is the fundamental molecule that performs numerous biological reactions and is crucial for maintaining cellular homeostasis. Studies have found that NAD+ decreases with age in certain tissues, and age-related NAD+ depletion affects physiological functions and contributes to various aging-related diseases. Supplementation of NAD+ precursor significantly elevates NAD+ levels in murine tissues, effectively mitigates metabolic syndrome, enhances cardiovascular health, protects against neurodegeneration, and boosts muscular strength. Despite the versatile therapeutic functions of NAD+ in animal studies, the efficacy of NAD+ precursors in clinical studies have been limited compared with that in the pre-clinical study. Clinical studies have demonstrated that NAD+ precursor treatment efficiently increases NAD+ levels in various tissues, though their clinical proficiency is insufficient to ameliorate the diseases. However, the latest studies regarding NAD+ precursors and their metabolism highlight the significant role of gut microbiota. The studies found that orally administered NAD+ intermediates interact with the gut microbiome. These findings provide compelling evidence for future trials to further explore the involvement of gut microbiota in NAD+ metabolism. Also, the reduced form of NAD+ precursor shows their potential to raise NAD+, though preclinical studies have yet to discover their efficacy. This review sheds light on NAD+ therapeutic efficiency in preclinical and clinical studies and the effect of the gut microbiota on NAD+ metabolism.
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Affiliation(s)
- Tooba Iqbal
- Department of Molecular and Medical Pharmacology, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Takashi Nakagawa
- Department of Molecular and Medical Pharmacology, Faculty of Medicine, University of Toyama, Toyama, Japan; Research Center for Pre-Disease Science, University of Toyama, Toyama, Japan.
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Özdemir İ, Etyemez S, Barker PB. High-field downfield MR spectroscopic imaging in the human brain. Magn Reson Med 2024. [PMID: 38469953 DOI: 10.1002/mrm.30075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 02/07/2024] [Accepted: 02/19/2024] [Indexed: 03/13/2024]
Abstract
PURPOSE To investigate the feasibility of downfield MR spectroscopic imaging (DF-MRSI) in the human brain at 7T. METHODS A 7T DF-MRSI pulse sequence was implemented based on the previously described methodology at 3T, with 3D phase-encoding,1 3 ‾ 3 1 ‾ $$ 1\overline{3}3\overline{1} $$ spectral-spatial excitation, and frequency selective refocusing. Data were pre-processed followed by analysis using the "LCModel" software package, and metabolite maps created from the LCModel results. Total scan time, including brain MRI and a water-reference MRSI, was 24 min. The sequence was tested in 10 normal volunteers. Estimated metabolite levels and uncertainty values (Cramer Rao lower bounds, CRLBs) for nine downfield peaks were compared between seven different brain regions, anterior cingulate cortex (ACC), centrum semiovale (CSO), corpus callosum (CC), cerebellar vermis (CV), dorsolateral prefrontal cortex (DLPFC), posterior cingulate cortex (PCC), and thalamus (Thal). RESULTS DF peaks were relatively uniformly distributed throughout the brain, with only a small number of peaks showing any significant regional variations. Most DF peaks had average CRLB<25% in most brain regions. Average SNR values were higher for the brain regions ACC and DLPFC (˜7 ± 0.95, mean ± SD) while in a range of 3.4-6.0 for other brain regions. Average linewidth (FWHM) values were greater than 35 Hz in the ACC, CV, and Thal, and 22 Hz in CC, CSO, DLPFC, and PCC. CONCLUSION High-field DF-MRSI is able to spatially map exchangeable protons in the human brain at high resolution and with near whole-brain coverage in acceptable scan times, and in the future may be used to study metabolism of brain tumors or other neuropathological disorders.
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Affiliation(s)
- İpek Özdemir
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Semra Etyemez
- Department of Obstetrics & Gynecology, Weill Cornell Medicine, New York, New York, USA
- Department of Psychiatry, Weill Cornell Medicine, New York, New York, USA
| | - Peter B Barker
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
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Swago S, Wilson NE, Elliott MA, Reddy Nanga RP, Reddy R, Witschey WR. Quantification of NAD + T 1 and T 2 relaxation times using downfield 1 H MRS at 7 T in human brain in vivo. bioRxiv 2024:2024.02.27.582276. [PMID: 38464048 PMCID: PMC10925302 DOI: 10.1101/2024.02.27.582276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Introduction The purpose of this study was to use a single-slice spectrally-selective sequence to measure T 1 and T 2 relaxation times of NAD + proton resonances in the downfield 1 H MRS spectrum in human brain at 7 T in vivo and assess the propagation of relaxation time uncertainty in NAD + quantification. Methods Downfield spectra from 7 healthy volunteers were acquired at multiple echo times in all subjects to measure T 2 relaxation, and saturation recovery data were to measure T 1 relaxation. The downfield acquisition used a spectrally-selective 90° sinc pulse for excitation centered at 9.1 ppm with a bandwidth of 2 ppm, followed by a 180° spatially-selective Shinnar-Le Roux refocusing pulse for localization. For the multiple echo experiment, spectra were collected with echo times ranging from 13 to 33 ms. For the saturation recovery experiment, saturation was performed prior to excitation using the same spectrally-selective sinc pulse as was used for excitation. Saturation delay times (TS) ranged from 100 to 600 ms. Uncertainty propagation analysis was performed analytically and with Monte Carlo simulation. Results The mean ± standard deviation of T 1 relaxation times of the H2, H6, and H4 protons were 152.7 ± 16.6, 163.6 ± 22.3, and 169.9 ± 11.2 ms, respectively. The mean ± standard deviation of T 2 relaxation times of the H2, H6, and H4 protons were 32.5 ± 7.0, 27.4 ± 5.2, and 38.1 ± 11.7 ms, respectively. The mean R 2 of the H2 and H6 T 1 fits were 0.98. The mean R 2 of the H4 proton T 1 fit was 0.96. The mean R 2 of the T 2 fits of the H2 and H4 proton resonances were 0.98, while the mean R 2 of the T 2 fits of the H4 proton was 0.93. The relative uncertainty in NAD + concentration due to relaxation time uncertainty was 8.5%-11%. Conclusion Using downfield spectrally-selective spectroscopy with single-slice localization, we found NAD + T 1 and T 2 relaxation times to be approximately 162 ms and 32 ms respectively in the human brain in vivo at 7 T.
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Chini CCS, Cordeiro HS, Tran NLK, Chini EN. NAD metabolism: Role in senescence regulation and aging. Aging Cell 2024; 23:e13920. [PMID: 37424179 PMCID: PMC10776128 DOI: 10.1111/acel.13920] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/15/2023] [Accepted: 06/20/2023] [Indexed: 07/11/2023] Open
Abstract
The geroscience hypothesis proposes that addressing the biology of aging could directly prevent the onset or mitigate the severity of multiple chronic diseases. Understanding the interplay between key aspects of the biological hallmarks of aging is essential in delivering the promises of the geroscience hypothesis. Notably, the nucleotide nicotinamide adenine dinucleotide (NAD) interfaces with several biological hallmarks of aging, including cellular senescence, and changes in NAD metabolism have been shown to be involved in the aging process. The relationship between NAD metabolism and cellular senescence appears to be complex. On the one hand, the accumulation of DNA damage and mitochondrial dysfunction induced by low NAD+ can promote the development of senescence. On the other hand, the low NAD+ state that occurs during aging may inhibit SASP development as this secretory phenotype and the development of cellular senescence are both highly metabolically demanding. However, to date, the impact of NAD+ metabolism on the progression of the cellular senescence phenotype has not been fully characterized. Therefore, to explore the implications of NAD metabolism and NAD replacement therapies, it is essential to consider their interactions with other hallmarks of aging, including cellular senescence. We propose that a comprehensive understanding of the interplay between NAD boosting strategies and senolytic agents is necessary to advance the field.
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Affiliation(s)
- Claudia Christiano Silva Chini
- Metabolism and Molecular Nutrition Laboratory, Kogod Center on Aging, Department of Anesthesiology and Perioperative MedicineMayo Clinic College of MedicineRochesterMinnesotaUSA
- Metabolism and Molecular Nutrition Laboratory, Kogod Center on Aging, Department of Anesthesiology and Perioperative MedicineMayo Clinic College of MedicineJacksonvilleFloridaUSA
| | - Heidi Soares Cordeiro
- Metabolism and Molecular Nutrition Laboratory, Kogod Center on Aging, Department of Anesthesiology and Perioperative MedicineMayo Clinic College of MedicineRochesterMinnesotaUSA
- Metabolism and Molecular Nutrition Laboratory, Kogod Center on Aging, Department of Anesthesiology and Perioperative MedicineMayo Clinic College of MedicineJacksonvilleFloridaUSA
| | - Ngan Le Kim Tran
- Center for Clinical and Translational Science and Mayo Clinic Graduate School of Biomedical SciencesMayo ClinicJacksonvilleFloridaUSA
| | - Eduardo Nunes Chini
- Metabolism and Molecular Nutrition Laboratory, Kogod Center on Aging, Department of Anesthesiology and Perioperative MedicineMayo Clinic College of MedicineRochesterMinnesotaUSA
- Metabolism and Molecular Nutrition Laboratory, Kogod Center on Aging, Department of Anesthesiology and Perioperative MedicineMayo Clinic College of MedicineJacksonvilleFloridaUSA
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Freeberg KA, Udovich CC, Martens CR, Seals DR, Craighead DH. Dietary Supplementation With NAD+-Boosting Compounds in Humans: Current Knowledge and Future Directions. J Gerontol A Biol Sci Med Sci 2023; 78:2435-2448. [PMID: 37068054 PMCID: PMC10692436 DOI: 10.1093/gerona/glad106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Indexed: 04/18/2023] Open
Abstract
Advancing age and many disease states are associated with declines in nicotinamide adenine dinucleotide (NAD+) levels. Preclinical studies suggest that boosting NAD+ abundance with precursor compounds, such as nicotinamide riboside or nicotinamide mononucleotide, has profound effects on physiological function in models of aging and disease. Translation of these compounds for oral supplementation in humans has been increasingly studied within the last 10 years; however, the clinical evidence that raising NAD+ concentrations can improve physiological function is unclear. The goal of this review was to synthesize the published literature on the effects of chronic oral supplementation with NAD+ precursors on healthy aging and age-related chronic diseases. We identified nicotinamide riboside, nicotinamide riboside co-administered with pterostilbene, and nicotinamide mononucleotide as the most common candidates in investigations of NAD+-boosting compounds for improving physiological function in humans. Studies have been performed in generally healthy midlife and older adults, adults with cardiometabolic disease risk factors such as overweight and obesity, and numerous patient populations. Supplementation with these compounds is safe, tolerable, and can increase the abundance of NAD+ and related metabolites in multiple tissues. Dosing regimens and study durations vary greatly across interventions, and small sample sizes limit data interpretation of physiological outcomes. Limitations are identified and future research directions are suggested to further our understanding of the potential efficacy of NAD+-boosting compounds for improving physiological function and extending human health span.
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Affiliation(s)
- Kaitlin A Freeberg
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA
| | - CeAnn C Udovich
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA
| | - Christopher R Martens
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, USA
| | - Douglas R Seals
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA
| | - Daniel H Craighead
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA
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Bhasin S, Seals D, Migaud M, Musi N, Baur JA. Nicotinamide Adenine Dinucleotide in Aging Biology: Potential Applications and Many Unknowns. Endocr Rev 2023; 44:1047-1073. [PMID: 37364580 DOI: 10.1210/endrev/bnad019] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 05/28/2023] [Accepted: 06/22/2023] [Indexed: 06/28/2023]
Abstract
Recent research has unveiled an expansive role of NAD+ in cellular energy generation, redox reactions, and as a substrate or cosubstrate in signaling pathways that regulate health span and aging. This review provides a critical appraisal of the clinical pharmacology and the preclinical and clinical evidence for therapeutic effects of NAD+ precursors for age-related conditions, with a particular focus on cardiometabolic disorders, and discusses gaps in current knowledge. NAD+ levels decrease throughout life; age-related decline in NAD+ bioavailability has been postulated to be a contributor to many age-related diseases. Raising NAD+ levels in model organisms by administration of NAD+ precursors improves glucose and lipid metabolism; attenuates diet-induced weight gain, diabetes, diabetic kidney disease, and hepatic steatosis; reduces endothelial dysfunction; protects heart from ischemic injury; improves left ventricular function in models of heart failure; attenuates cerebrovascular and neurodegenerative disorders; and increases health span. Early human studies show that NAD+ levels can be raised safely in blood and some tissues by oral NAD+ precursors and suggest benefit in preventing nonmelanotic skin cancer, modestly reducing blood pressure and improving lipid profile in older adults with obesity or overweight; preventing kidney injury in at-risk patients; and suppressing inflammation in Parkinson disease and SARS-CoV-2 infection. Clinical pharmacology, metabolism, and therapeutic mechanisms of NAD+ precursors remain incompletely understood. We suggest that these early findings provide the rationale for adequately powered randomized trials to evaluate the efficacy of NAD+ augmentation as a therapeutic strategy to prevent and treat metabolic disorders and age-related conditions.
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Affiliation(s)
- Shalender Bhasin
- Department of Medicine, Harvard Medical School, Research Program in Men's Health: Aging and Metabolism, Boston Claude D. Pepper Older Americans Independence Center, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Douglas Seals
- Department of Integrative Physiology and Medicine, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Marie Migaud
- Department of Pharmacology, Mitchell Cancer Institute, College of Medicine, University of Southern Alabama, Mobile, AL 36688, USA
| | - Nicolas Musi
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Joseph A Baur
- Department of Physiology, Institute for Diabetes, Obesity & Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Song Q, Zhou X, Xu K, Liu S, Zhu X, Yang J. The Safety and Antiaging Effects of Nicotinamide Mononucleotide in Human Clinical Trials: an Update. Adv Nutr 2023; 14:1416-1435. [PMID: 37619764 PMCID: PMC10721522 DOI: 10.1016/j.advnut.2023.08.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 08/02/2023] [Accepted: 08/15/2023] [Indexed: 08/26/2023] Open
Abstract
The importance of nicotinamide adenine dinucleotide (NAD+) in human physiology is well recognized. As the NAD+ concentration in human skin, blood, liver, muscle, and brain are thought to decrease with age, finding ways to increase NAD+ status could possibly influence the aging process and associated metabolic sequelae. Nicotinamide mononucleotide (NMN) is a precursor for NAD+ biosynthesis, and in vitro/in vivo studies have demonstrated that NMN supplementation increases NAD+ concentration and could mitigate aging-related disorders such as oxidative stress, DNA damage, neurodegeneration, and inflammatory responses. The promotion of NMN as an antiaging health supplement has gained popularity due to such findings; however, since most studies evaluating the effects of NMN have been conducted in cell or animal models, a concern remains regarding the safety and physiological effects of NMN supplementation in the human population. Nonetheless, a dozen human clinical trials with NMN supplementation are currently underway. This review summarizes the current progress of these trials and NMN/NAD+ biology to clarify the potential effects of NMN supplementation and to shed light on future study directions.
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Affiliation(s)
- Qin Song
- Department of Occupational and Environmental Health, Hangzhou Normal University School of Public Health, Hangzhou, China
| | - Xiaofeng Zhou
- Department of Radiotherapy, The 2(nd) Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Kexin Xu
- Department of Nutritional and Toxicological Science, Hangzhou Normal University School of Public Health, Hangzhou, China
| | - Sishi Liu
- Department of Nutritional and Toxicological Science, Hangzhou Normal University School of Public Health, Hangzhou, China
| | - Xinqiang Zhu
- Core Facility, The 4(th) Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, China.
| | - Jun Yang
- Department of Nutritional and Toxicological Science, Hangzhou Normal University School of Public Health, Hangzhou, China; Zhejiang Provincial Center for Uterine Cancer Diagnosis and Therapy Research, The Affiliated Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
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Özdemir İ, Ganji S, Gillen J, Etyemez S, Považan M, Barker PB. Downfield proton MRSI with whole-brain coverage at 3T. Magn Reson Med 2023; 90:814-822. [PMID: 37249071 PMCID: PMC10330175 DOI: 10.1002/mrm.29706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 04/03/2023] [Accepted: 04/27/2023] [Indexed: 05/31/2023]
Abstract
PURPOSE To develop a 3D downfield (DF) MRSI protocol with whole brain coverage and post-processing pipeline for creation of metabolite maps. METHODS A 3D, circularly phase-encoded version of the previously developed 2D DF MRSI sequence with1 3 ‾ 3 1 ‾ $$ 1\overline{3}3\overline{1} $$ spectral-spatial excitation and frequency selective refocusing was implemented and tested in five healthy volunteers at 3T. The DF metabolite maps with a nominal spatial resolution of 0.7 cm3 were recorded in eight slices at 3T in a scan time of 22 m 40 s. An MRSI post-processing pipeline was developed to create DF metabolite maps. Metabolite concentrations and uncertainty estimates were compared between region differences for nine DF peaks. RESULTS LCModel analysis showed Cramer Rao lower bounds average values of 3%-4% for protein amide resonances in the three selected regions (anterior cingulate, dorsolateral prefrontal cortex, and centrum semiovale); Cramer Rao lower bounds were somewhat higher for individual peaks but for the most part were less than 20%. While DF concentration maps were visually quite homogeneous throughout the brain, general linear regression analysis corrected for multiple comparisons found significant differences between centrum semiovale and dorsolateral prefrontal cortex for peaks at 7.09 ppm (p = 0.014), 7.90 ppm (p = 0.009), 8.18 ppm (p = 0.009), combined amides (p = 0.009), and between anterior cingulate and dorsolateral prefrontal cortex for the 7.30 ppm peak (p = 0.020). Cramer Rao lower bounds values were not significantly different between brain regions for any of the DF peaks. CONCLUSION The 3D DF MRSI of the human brain at 3T with wide spatial coverage for the mapping of exchangeable amide and other resonances is feasible at a nominal spatial resolution of 0.7 cm3 .
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Affiliation(s)
- İpek Özdemir
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | | | - Joseph Gillen
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F.M. Kennedy Krieger Institute, Baltimore, MD, United States
| | - Semra Etyemez
- Department of Obstetrics & Gynecology, Weill Cornell Medicine, New York, NY, United States
| | | | - Peter B. Barker
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F.M. Kennedy Krieger Institute, Baltimore, MD, United States
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11
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Nanga RPR, Elliott MA, Swain A, Wilson NE, Swago S, Witschey WR, Reddy R. Identification of new resonances in downfield 1 H MRS of human calf muscle in vivo: Potentially metabolite precursors for skeletal muscle NAD . Magn Reson Med 2023. [PMID: 37125620 DOI: 10.1002/mrm.29687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/20/2023] [Accepted: 04/14/2023] [Indexed: 05/02/2023]
Abstract
PURPOSE The purpose of this study was to identify and characterize newly discovered resonances appearing in the downfield proton MR spectrum (DF 1 H MRS) of the human calf muscle in vivo at 7T. METHODS Downfield 1 H MRS was performed on the calf muscle of five healthy volunteers at 7T. A spectrally selective 90° E-BURP RF pulse with an excitation center frequency at 10.3 ppm and an excitation bandwidth of 2 ppm was used for DF 1 H MRS acquisition. RESULTS In all participants, we observed new resonances at 9.7, 10.1, 10.3, and 10.9 ppm in the DF 1 H MRS. Phantom experiments at 37°C strongly suggest the new resonance at 9.7 ppm could be from H2-proton of the nicotinamide rings in nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN) while the resonance at 10.1 ppm could be attributed to the indole -NH proton of L-tryptophan. We observed that the resonances at 10.1 and 10.9 ppm are significantly suppressed when the water resonance is saturated, indicating that these peaks have either 1 H chemical exchange or cross-relaxation with water. Conversely, the resonances at 9.7 and 10.3 ppm exhibit moderate signal reduction in the presence of water saturation. CONCLUSION We have identified new proton resonances in vivo in human calf muscle occurring at chemical shifts of 9.7, 10.1, 10.3, and 10.9 ppm. These preliminary results are promising for investigating the role of NR/NMN and L-tryptophan metabolism in understanding the de novo and salvage pathways of NAD+ synthesis in skeletal muscle.
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Affiliation(s)
- Ravi Prakash Reddy Nanga
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Mark A Elliott
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Anshuman Swain
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Neil E Wilson
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Sophia Swago
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Walter R Witschey
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ravinder Reddy
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, Pennsylvania, USA
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12
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Nagahisa T, Kosugi S, Yamaguchi S. Interactions between Intestinal Homeostasis and NAD + Biology in Regulating Incretin Production and Postprandial Glucose Metabolism. Nutrients 2023; 15:nu15061494. [PMID: 36986224 PMCID: PMC10052115 DOI: 10.3390/nu15061494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/17/2023] [Accepted: 03/19/2023] [Indexed: 03/30/2023] Open
Abstract
The intestine has garnered attention as a target organ for developing new therapies for impaired glucose tolerance. The intestine, which produces incretin hormones, is the central regulator of glucose metabolism. Glucagon-like peptide-1 (GLP-1) production, which determines postprandial glucose levels, is regulated by intestinal homeostasis. Nicotinamide phosphoribosyltransferase (NAMPT)-mediated nicotinamide adenine dinucleotide (NAD+) biosynthesis in major metabolic organs such as the liver, adipose tissue, and skeletal muscle plays a crucial role in obesity- and aging-associated organ derangements. Furthermore, NAMPT-mediated NAD+ biosynthesis in the intestines and its upstream and downstream mediators, adenosine monophosphate-activated protein kinase (AMPK) and NAD+-dependent deacetylase sirtuins (SIRTs), respectively, are critical for intestinal homeostasis, including gut microbiota composition and bile acid metabolism, and GLP-1 production. Thus, boosting the intestinal AMPK-NAMPT-NAD+-SIRT pathway to improve intestinal homeostasis, GLP-1 production, and postprandial glucose metabolism has gained significant attention as a novel strategy to improve impaired glucose tolerance. Herein, we aimed to review in detail the regulatory mechanisms and importance of intestinal NAMPT-mediated NAD+ biosynthesis in regulating intestinal homeostasis and GLP-1 secretion in obesity and aging. Furthermore, dietary and molecular factors regulating intestinal NAMPT-mediated NAD+ biosynthesis were critically explored to facilitate the development of new therapeutic strategies for postprandial glucose dysregulation.
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Affiliation(s)
- Taichi Nagahisa
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Shotaro Kosugi
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Shintaro Yamaguchi
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
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13
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Swago S, Elliott MA, Nanga RPR, Wilson NE, Cember A, Reddy R, Witschey WR. Quantification of cross-relaxation in downfield 1 H MRS at 7 T in human calf muscle. Magn Reson Med 2023; 90:11-20. [PMID: 36807934 PMCID: PMC10149600 DOI: 10.1002/mrm.29615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 12/30/2022] [Accepted: 01/23/2023] [Indexed: 02/20/2023]
Abstract
PURPOSE The purpose of this study was to characterize the 1 H downfield MR spectrum from 8.0 to 10.0 ppm of human skeletal muscle at 7 T and determine the T1 and cross-relaxation rates of observed resonances. METHODS We performed downfield MRS in the calf muscle of 7 healthy volunteers. Single-voxel downfield MRS was collected using alternately selective or broadband inversion-recovery sequences and spectrally selective 90° E-BURP RF pulse excitation centered at 9.0 ppm with bandwidth = 600 Hz (2.0 ppm). MRS was collected using TIs of 50-2500 ms. We modeled recovery of the longitudinal magnetization of three observable resonances using two models: (1) a three-parameter model accounting for the apparent T1 recovery and (2) a Solomon model explicitly including cross-relaxation effects. RESULTS Three resonances were observed in human calf muscle at 7 T at 8.0, 8.2, and 8.5 ppm. We found broadband (broad) and selective (sel) inversion recovery T1 = mean ± SD (ms): T1-broad,8.0ppm = 2108.2 ± 664.5, T1-sel,8.0ppm = 753.6 ± 141.0 (p = 0.003); T1-broad,8.2ppm = 2033.5 ± 338.4, T1-sel,8.2ppm = 135.3 ± 35.3 (p < 0.0001); and T1-broad,8.5ppm = 1395.4 ± 75.4, T1-sel,8.5ppm = 107.1 ± 40.0 (p < 0.0001). Using the Solomon model, we found T1 = mean ± SD (ms): T1-8.0ppm = 1595.6 ± 491.1, T1-8.2ppm = 1737.2 ± 963.7, and T1-8.5ppm = 849.8 ± 282.0 (p = 0.04). Post hoc tests corrected for multiple comparisons showed no significant difference in T1 between peaks. The cross-relaxation rate σAB = mean ± SD (Hz) of each peak was σAB,8.0ppm = 0.76 ± 0.20, σAB,8.2ppm = 5.31 ± 2.27, and σAB,8.5ppm = 7.90 ± 2.74 (p < 0.0001); post hoc t-tests revealed the cross-relaxation rate of the 8.0 ppm peak was significantly slower than the peaks at 8.2 ppm (p = 0.0018) and 8.5 ppm (p = 0.0005). CONCLUSION We found significant differences in effective T1 and cross-relaxation rates of 1 H resonances between 8.0 and 8.5 ppm in the healthy human calf muscle at 7 T.
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Affiliation(s)
- Sophia Swago
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Mark A Elliott
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ravi Prakash Reddy Nanga
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Neil E Wilson
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Abigail Cember
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ravinder Reddy
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Walter R Witschey
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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14
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Pencina KM, Lavu S, Dos Santos M, Beleva YM, Cheng M, Livingston D, Bhasin S. MIB-626, an Oral Formulation of a Microcrystalline Unique Polymorph of β-Nicotinamide Mononucleotide, Increases Circulating Nicotinamide Adenine Dinucleotide and its Metabolome in Middle-Aged and Older Adults. J Gerontol A Biol Sci Med Sci 2023; 78:90-96. [PMID: 35182418 DOI: 10.1093/gerona/glac049] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Nicotinamide adenine dinucleotide (NAD) precursors, nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) extend healthspan and ameliorate some age-related conditions in model organisms. However, early-phase trials of NAD precursors have yielded varying results and their pharmacokinetics remain incompletely understood. Here, we report the pharmacokinetics and pharmacodynamics of MIB-626, a microcrystalline unique polymorph βNMN formulation. METHODS In this double-blind, placebo-controlled study, 32 overweight or obese adults, 55-80 years, were block-randomized, stratified by sex, to 1 000-mg MIB-626 once daily, twice daily, or placebo for 14 days. NMN, NAD, and NAD metabolome were measured using liquid chromatography-tandem mass spectrometry. RESULTS Participant characteristics were similar across groups. MIB-626 was well tolerated and frequency of adverse events was similar across groups. Blood NMN concentrations on Day 14 in MIB-626-treated groups were significantly higher compared to placebo (1.7-times and 3.7-times increase above baseline in 1 000 mg once-daily and twice-daily groups in mean AUClast, respectively). MIB-626 treatment was associated with substantial dose-related increases in blood NAD levels. Blood levels of NAD metabolites were higher in NMN-treated participants on Days 8 and 14 than at baseline. Changes in NMN or NAD levels were not related to sex, body mass index, or age. Very little unmodified NMN was excreted in the urine. CONCLUSION MIB-626 1 000 mg once-daily or twice-daily regimens were safe and associated with substantial dose-related increases in blood NAD levels and its metabolome. These foundational data that were obtained using a pharmaceutical-grade βNMN, standardized sample collection, and validated liquid chromatography-tandem mass spectrometry assays, should facilitate design of efficacy trials in disease conditions.
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Affiliation(s)
- Karol M Pencina
- Research Program in Men's Health: Aging and Metabolism, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Siva Lavu
- Metro International Biotech, Worcester, Massachusetts, USA
| | - Marcello Dos Santos
- Research Program in Men's Health: Aging and Metabolism, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Yusnie M Beleva
- Research Program in Men's Health: Aging and Metabolism, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Ming Cheng
- Research Program in Men's Health: Aging and Metabolism, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | | | - Shalender Bhasin
- Research Program in Men's Health: Aging and Metabolism, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
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15
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Nanga RPR, Elliott MA, Swain A, Wilson N, Swago S, Soni ND, Witschey WR, Reddy R. Identification of l-Tryptophan by down-field 1 H MRS: A precursor for brain NAD + and serotonin syntheses. Magn Reson Med 2022; 88:2371-2377. [PMID: 36005819 PMCID: PMC10165892 DOI: 10.1002/mrm.29414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/14/2022] [Accepted: 07/27/2022] [Indexed: 11/11/2022]
Abstract
PURPOSE To explore the presence of new resonances beyond 9.4 ppm from the human brain, down-field proton MRS was performed in vivo in the human brain on 6 healthy volunteers at 7 T. METHODS To maximize the SNR, a large voxel was placed within the brain to cover the maximal area in such a way that sinus cavities were avoided. A spectrally selective 90° E-BURP pulse with an excitation bandwidth of 2 ppm was used to probe the spectral chemical shift range between 9.1 and 10.5 ppm. The E-BURP pulse was integrated with PRESS spatial localization to obtain non-water-suppressed proton MR spectra from the desired spectral region. RESULTS In the down-field proton MRS obtained from all of the volunteers scanned, we identified a new peak consistently resonating at 10.1 ppm. Protons associated with this resonance are in cross-relaxation with the bulk water, as demonstrated by the water saturation and deuterium exchange experiments. CONCLUSION Based on the chemical shift, this new peak was identified as the indole (-NH) proton of l-tryptophan (l-TRP) and was further confirmed from phantom experiments on l-TRP. These promising preliminary results potentially pave the way to investigate the role of cerebral metabolism of l-TRP in healthy and disease conditions.
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Affiliation(s)
- Ravi Prakash Reddy Nanga
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA
| | - Mark A. Elliott
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA
| | - Anshuman Swain
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA
| | - Neil Wilson
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA
| | - Sophia Swago
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA
| | - Narayan Datt Soni
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA
| | - Walter R. Witschey
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA
| | - Ravinder Reddy
- Center for Advanced Metabolic Imaging in Precision Medicine, Department of Radiology, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA
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16
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Conlon NJ. The Role of NAD+ in Regenerative Medicine. Plast Reconstr Surg 2022; 150:41S-48S. [PMID: 36170435 PMCID: PMC9512238 DOI: 10.1097/prs.0000000000009673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The understanding of the molecular and cellular basis of aging has grown exponentially over recent years, and it is now accepted within the scientific community that aging is a malleable process; just as it can be accelerated, it can also be slowed and even reversed. This has far-reaching implications for our attitude and approach toward aging, presenting the opportunity to enter a new era of cellular regenerative medicine to not only manage the external signs of aging but also to develop therapies that support the body to repair and restore itself back to a state of internal well-being. A wealth of evidence now demonstrates that a decline in cellular nicotinamide adenine dinucleotide (NAD+) is a feature of aging and may play a role in the process. NAD+ plays a pivotal role in cellular metabolism and is a co-substrate for enzymes that play key roles in pathways that modify aging. Thus, interventions that increase NAD+ may slow aspects of the aging trajectory, and there is great interest in methods for cellular NAD+ restoration. Given these recent advancements in understanding the cellular aging process, it is important that there is an integration between the basic scientists who are investigating the underlying mechanisms of cellular aging and the surgeons and aesthetic practitioners who are providing antiaging therapies. This will allow the effective translation of this vastly complex area of biology into clinical practice so that people can continue to not only stay looking younger for longer but also experience improved health and wellness.
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Balashova NV, Zavileyskiy LG, Artiukhov AV, Shaposhnikov LA, Sidorova OP, Tishkov VI, Tramonti A, Pometun AA, Bunik VI. Efficient Assay and Marker Significance of NAD+ in Human Blood. Front Med (Lausanne) 2022; 9:886485. [PMID: 35665345 PMCID: PMC9162244 DOI: 10.3389/fmed.2022.886485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/07/2022] [Indexed: 11/13/2022] Open
Abstract
Oxidized nicotinamide adenine dinucleotide (NAD+) is a biological molecule of systemic importance. Essential role of NAD+ in cellular metabolism relies on the substrate action in various redox reactions and cellular signaling. This work introduces an efficient enzymatic assay of NAD+ content in human blood using recombinant formate dehydrogenase (FDH, EC 1.2.1.2), and demonstrates its diagnostic potential, comparing NAD+ content in the whole blood of control subjects and patients with cardiac or neurological pathologies. In the control group (n = 22, 25–70 years old), our quantification of the blood concentration of NAD+ (18 μM, minimum 15, max 23) corresponds well to NAD+ quantifications reported in literature. In patients with demyelinating neurological diseases (n = 10, 18–55 years old), the NAD+ levels significantly (p < 0.0001) decrease (to 14 μM, min 13, max 16), compared to the control group. In cardiac patients with the heart failure of stage II and III according to the New York Heart Association (NYHA) functional classification (n = 24, 42–83 years old), the blood levels of NAD+ (13 μM, min 9, max 18) are lower than those in the control subjects (p < 0.0001) or neurological patients (p = 0.1). A better discrimination of the cardiac and neurological patients is achieved when the ratios of NAD+ to the blood creatinine levels, mean corpuscular volume or potassium ions are compared. The proposed NAD+ assay provides an easy and robust tool for clinical analyses of an important metabolic indicator in the human blood.
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Affiliation(s)
- Natalia V. Balashova
- Department of Clinical Laboratory Diagnostics, Faculty of Advanced Medicine, M.F. Vladimirsky Moscow Regional Research and Clinical Institute (MONIKI), Moscow, Russia
- Department of Dietetics and Clinical Nutritionology, Faculty of Continuing Medical Education, RUDN Medical Institute, Moscow, Russia
| | - Lev G. Zavileyskiy
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
| | - Artem V. Artiukhov
- Department of Biokinetics, A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- Department of Biochemistry, Sechenov University, Moscow, Russia
| | - Leonid A. Shaposhnikov
- Department of Chemical Enzymology, Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russia
| | - Olga P. Sidorova
- Department of Neurology, Faculty of Advanced Medicine, M.F. Vladimirsky Moscow Regional Research and Clinical Institute (MONIKI), Moscow, Russia
| | - Vladimir I. Tishkov
- Department of Chemical Enzymology, Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russia
- Bach Institute of Biochemistry, Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences, Moscow, Russia
| | - Angela Tramonti
- Institute of Molecular Biology and Pathology, Italian National Research Council, Department of Biochemical Sciences “A. Rossi Fanelli,” Sapienza University of Rome, Rome, Italy
| | - Anastasia A. Pometun
- Department of Chemical Enzymology, Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russia
- Bach Institute of Biochemistry, Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences, Moscow, Russia
| | - Victoria I. Bunik
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
- Department of Biokinetics, A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- Department of Biochemistry, Sechenov University, Moscow, Russia
- *Correspondence: Victoria I. Bunik,
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18
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Dziadosz M, Hoefemann M, Döring A, Marjańska M, Auerbach EJ, Kreis R. Quantification of
NAD
+
in human brain with
1
H MR
spectroscopy at 3 T: Comparison of three localization techniques with different handling of water magnetization. Magn Reson Med 2022; 88:1027-1038. [PMID: 35526238 PMCID: PMC9322547 DOI: 10.1002/mrm.29267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/11/2022] [Accepted: 03/25/2022] [Indexed: 12/16/2022]
Abstract
Purpose The detection of nicotinamide‐adenine‐dinucleotide (NAD+) is challenging using standard 1H MR spectroscopy, because it is of low concentration and affected by polarization‐exchange with water. Therefore, this study compares three techniques to access NAD+ quantification at 3 T–one with and two without water presaturation. Methods A large brain volume in 10 healthy subjects was investigated with three techniques: semi‐LASER with water‐saturation (WS) (TE = 35 ms), semi‐LASER with metabolite‐cycling (MC) (TE = 35 ms), and the non‐water‐excitation (nWE) technique 2D ISIS‐localization with chemical‐shift‐selective excitation (2D I‐CSE) (TE = 10.2 ms). Spectra were quantified with optimized modeling in FiTAID. Results NAD+ could be well quantified in cohort‐average spectra with all techniques. Obtained apparent NAD+ tissue contents are all lower than expected from literature confirming restricted visibility by 1H MRS. The estimated value from WS‐MRS (58 μM) was considerably lower than those obtained with non‐WS techniques (146 μM for MC‐semi‐LASER and 125 μM for 2D I‐CSE). The nWE technique with shortest TE gave largest NAD+ signals but suffered from overlap with large amide signals. MC‐semi‐LASER yielded best estimation precision as reflected in relative Cramer‐Rao bounds (14%, 21 μM/146 μM) and also best robustness as judged by the coefficient‐of‐variance over the cohort (11%, 10 μM/146 μM). The MR‐visibility turned out as 16% with WS and 41% with MC. Conclusion Three methods to assess NAD+ in human brain at 3 T have been compared. NAD+ could be detected with a visibility of ∼41% for the MC method. This may open a new window for the observation of pathological changes in the clinical research setting.
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Affiliation(s)
- Martyna Dziadosz
- MR Methodology, Department for Diagnostic and Interventional Neuroradiology & Department for Biomedical Research University of Bern Bern Switzerland
- Graduate School for Cellular and Biomedical Sciences University of Bern Bern Switzerland
- Translational Imaging Center (TIC) Swiss Institute for Translational and Entrepreneurial Medicine Bern Switzerland
| | - Maike Hoefemann
- MR Methodology, Department for Diagnostic and Interventional Neuroradiology & Department for Biomedical Research University of Bern Bern Switzerland
- Graduate School for Cellular and Biomedical Sciences University of Bern Bern Switzerland
- Translational Imaging Center (TIC) Swiss Institute for Translational and Entrepreneurial Medicine Bern Switzerland
| | - André Döring
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology Cardiff University Cardiff UK
| | - Malgorzata Marjańska
- Department of Radiology, Center for Magnetic Resonance Research University of Minnesota Minneapolis Minnesota USA
| | - Edward John Auerbach
- Department of Radiology, Center for Magnetic Resonance Research University of Minnesota Minneapolis Minnesota USA
| | - Roland Kreis
- MR Methodology, Department for Diagnostic and Interventional Neuroradiology & Department for Biomedical Research University of Bern Bern Switzerland
- Translational Imaging Center (TIC) Swiss Institute for Translational and Entrepreneurial Medicine Bern Switzerland
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19
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Gonçalves SI, Simões RV, Shemesh N. Short TE downfield magnetic resonance spectroscopy in a mouse model of brain glioma. Magn Reson Med 2022; 88:524-536. [PMID: 35315536 DOI: 10.1002/mrm.29243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 11/11/2022]
Abstract
PURPOSE Enhanced cell proliferation in tumors can be associated with altered metabolic profiles and dramatic microenvironmental changes. Downfield magnetic resonance spectroscopy (MRS) has received increasing attention due to its ability to report on labile resonances of molecules not easily detected in upfield 1 H MRS. Image-selected-in-vivo-spectroscopy-relaxation enhanced MRS (iRE-MRS) was recently introduced for acquiring short echo-time (TE) spectra. Here, iRE-MRS was used to investigate in-vivo downfield spectra in glioma-bearing mice. METHODS Experiments were performed in vivo in an immunocompetent glioma mouse model at 9.4 T using a cryogenic coil. iRE-MRS spectra were acquired in N = 6 glioma-bearing mice (voxel size = 2.23 mm3 ) and N = 6 control mice. Spectra were modeled by a sum of Lorentzian peaks simulating known downfield resonances, and differences between controls and tumors were quantified using relative peak areas. RESULTS Short TE tumor spectra exhibited large qualitative differences compared to control spectra. Most peaks appeared modulated, with strong attenuation of NAA (∼7.82, 7.86 ppm) and changes in relative peak areas between 6.75 and 8.49 ppm. Peak areas tended to be smaller for DF6.83 , DF7.60 , DF8.18 and NAA; and larger for DF7.95 and DF8.24 . Differences were also detected in signals resonating above 8.5 ppm, assumed to arise from NAD+. CONCLUSIONS In-vivo downfield 1 H iRE-MRS of mouse glioma revealed differences between controls and tumor bearing mice, including in metabolites which are not easily detectable in the more commonly investigated upfield spectrum. These findings motivate future downfield MRS investigations exploring pH and exchange contributions to these differences.
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Affiliation(s)
| | - Rui V Simões
- Champalimaud Research, Champalimaud Foundation, Lisbon, Portugal
| | - Noam Shemesh
- Champalimaud Research, Champalimaud Foundation, Lisbon, Portugal
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20
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Conlon N, Ford D. A systems-approach to NAD+ restoration. Biochem Pharmacol 2022; 198:114946. [DOI: 10.1016/j.bcp.2022.114946] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/02/2022] [Accepted: 02/02/2022] [Indexed: 12/12/2022]
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21
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Peluso A, Damgaard MV, Mori MAS, Treebak JT. Age-Dependent Decline of NAD +-Universal Truth or Confounded Consensus? Nutrients 2021; 14:nu14010101. [PMID: 35010977 PMCID: PMC8747183 DOI: 10.3390/nu14010101] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 12/16/2022] Open
Abstract
Nicotinamide adenine dinucleotide (NAD+) is an essential molecule involved in various metabolic reactions, acting as an electron donor in the electron transport chain and as a co-factor for NAD+-dependent enzymes. In the early 2000s, reports that NAD+ declines with aging introduced the notion that NAD+ metabolism is globally and progressively impaired with age. Since then, NAD+ became an attractive target for potential pharmacological therapies aiming to increase NAD+ levels to promote vitality and protect against age-related diseases. This review summarizes and discusses a collection of studies that report the levels of NAD+ with aging in different species (i.e., yeast, C. elegans, rat, mouse, monkey, and human), to determine whether the notion that overall NAD+ levels decrease with aging stands true. We find that, despite systematic claims of overall changes in NAD+ levels with aging, the evidence to support such claims is very limited and often restricted to a single tissue or cell type. This is particularly true in humans, where the development of NAD+ levels during aging is still poorly characterized. There is a need for much larger, preferably longitudinal, studies to assess how NAD+ levels develop with aging in various tissues. This will strengthen our conclusions on NAD metabolism during aging and should provide a foundation for better pharmacological targeting of relevant tissues.
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Affiliation(s)
- Augusto Peluso
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK 2200 Copenhagen, Denmark; (A.P.); (M.V.D.)
| | - Mads V. Damgaard
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK 2200 Copenhagen, Denmark; (A.P.); (M.V.D.)
| | - Marcelo A. S. Mori
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, São Paulo 13083-862, Brazil;
- Obesity and Comorbidities Research Center, University of Campinas, São Paulo 13083-862, Brazil
- Experimental Medicine Research Cluster, University of Campinas, São Paulo 13083-862, Brazil
| | - Jonas T. Treebak
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK 2200 Copenhagen, Denmark; (A.P.); (M.V.D.)
- Correspondence: ; Tel.: +45-24805398
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[Potential significance of NAD + biology translational research in super-aged Japan]. Nihon Ronen Igakkai Zasshi 2020; 57:213-23. [PMID: 32893201 DOI: 10.3143/geriatrics.57.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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23
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Cuenoud B, Ipek Ö, Shevlyakova M, Beaumont M, Cunnane SC, Gruetter R, Xin L. Brain NAD Is Associated With ATP Energy Production and Membrane Phospholipid Turnover in Humans. Front Aging Neurosci 2020; 12:609517. [PMID: 33390929 PMCID: PMC7772416 DOI: 10.3389/fnagi.2020.609517] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 11/23/2020] [Indexed: 12/16/2022] Open
Abstract
The brain requires a large amount of energy, mostly derived from the metabolism of glucose, which decreases substantially with age and neurological diseases. While mounting evidence in model organisms illustrates the central role of brain nicotinamide adenine dinucleotide (NAD) for maintaining energy homeostasis, similar data are sparse in humans. This study explores the correlations between brain NAD, energy production and membrane phospholipid metabolism by 31-phosphorous magnetic resonance spectroscopy (31P-MRS) across 50 healthy participants including a young (mean age 27.1-year-old) and middle-aged (mean age 56.4-year-old) group. The analysis revealed that brain NAD level and NAD+/NADH redox ratio were positively associated with ATP level and the rate of energy production, respectively. Moreover, a metabolic network linking NAD with membrane phospholipid metabolism, energy production, and aging was identified. An inverted trend between age and NAD level was detected. These results pave the way for the use of 31P-MRS as a powerful non-invasive tool to support the development of new therapeutic interventions targeting NAD associated phospho-metabolic pathways in brain aging and neurological diseases.
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Affiliation(s)
| | - Özlem Ipek
- School of Biomedical Imaging & Imaging Sciences, King's College London, London, United Kingdom
| | - Maya Shevlyakova
- Clinical Development Unit, Nestlé Research Center, Lausanne, Switzerland
| | - Maurice Beaumont
- Clinical Development Unit, Nestlé Research Center, Lausanne, Switzerland
| | - Stephen C Cunnane
- Department of Medicine, Université de Sherbrooke and Research Center on Aging, Sherbrooke, QC, Canada
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Lijing Xin
- Center for Biomedical Imaging, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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Dziadosz M, Bogner W, Kreis R. Non-water-excitation MR spectroscopy techniques to explore exchanging protons in human brain at 3 T. Magn Reson Med 2020; 84:2352-2363. [PMID: 32602971 DOI: 10.1002/mrm.28322] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/23/2020] [Accepted: 04/23/2020] [Indexed: 12/13/2022]
Abstract
PURPOSE To develop localization sequences for in vivo MR spectroscopy (MRS) on clinical scanners of 3 T to record spectra that are not influenced by magnetization transfer from water. METHODS Image-selected in vivo spectroscopy (ISIS) localization and chemical-shift-selective excitation (termed I-CSE) was combined in two ways: first, full ISIS localization plus a frequency-selective spin-echo and second, two-dimensional (2D) ISIS plus a frequency-selective excitation and slice-selective refocusing. The techniques were evaluated at 3 T in phantoms and human subjects in comparison to standard techniques with water presaturation or metabolite-cycling. ISIS included gradient-modulated offset-independent adiabatic (GOIA)-type adiabatic inversion pulses; echo times were 8-10 ms. RESULTS The novel 2D and 3D I-CSE methods yield upfield spectra that are comparable to those from standard MRS, except for shorter echo times and a limited frequency range. On the downfield/high-frequency side, they yield much more signal for exchangeable protons when compared to MRS with water presaturation or metabolite-cycling and longer echo times. CONCLUSION Novel non-water-excitation MRS sequences offer substantial benefits for the detection of metabolite signals that are otherwise suppressed by saturation transfer from water. Avoiding water saturation and using very short echo times allows direct observation of faster exchanging moieties than was previously possible at 3 T and additionally makes the methods less susceptible to fast T2 relaxation.
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Affiliation(s)
- Martyna Dziadosz
- Departments of Radiology and Biomedical Research, University of Bern, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Wolfgang Bogner
- High-field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Vienna, Austria
| | - Roland Kreis
- Departments of Radiology and Biomedical Research, University of Bern, Bern, Switzerland
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Abstract
Nicotinamide adenine dinucleotide (NAD+) is an essential metabolite that is reported to decline in concentration in tissues of aged animals. Strategies to increase NAD+ availability have shown promise in treating many conditions in rodents, including age-related degeneration, which has in turn driven intense interest in the effects of supplements on human health. However, many aspects of NAD+ metabolism remain poorly understood, and human data are limited. Here, we discuss the state of the evidence for an age-related decline in NAD+, along with potential mechanistic explanations, including increased consumption or decreased synthesis of NAD+ and changes in the composition of cells or tissues with age. Key challenges for the field involve the development of better tools to resolve information on the NAD+ content of specific cells and subcellular compartments as well as determining the threshold levels at which NAD+ depletion triggers physiological consequences in different tissues. Understanding how NAD+ metabolism changes with age in humans may ultimately allow the design of more targeted strategies to maintain its availability, such as inhibition of key consumers in specific tissues or direct delivery of precursors to sites of deficiency. In the meantime, human clinical trials with oral supplements are poised to provide some of the first direct evidence as to whether increasing NAD+ availability can impact human physiology. Thus, it is an exciting time for NAD+ research, with much remaining to be learned in terms of both basic biology and potential therapeutic applications.
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Affiliation(s)
- Melanie R McReynolds
- Lewis-Sigler Institute for Integrative Genomics, Department of Chemistry, Princeton University, Princeton, NJ, United States of America
| | - Karthikeyani Chellappa
- Department of Physiology, Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Joseph A Baur
- Department of Physiology, Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America.
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