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Charles S, Liu Y, Bharmal SH, Kimita W, Petrov MS. Effect of Acute Nutritional Ketosis on Circulating Levels of Growth Differentiation Factor 15: Findings from a Cross-Over Randomised Controlled Trial. Biomolecules 2024; 14:665. [PMID: 38927068 PMCID: PMC11202064 DOI: 10.3390/biom14060665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 05/30/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
Exogenous supplementation with ketone beverages has been shown to reduce plasma glucose levels during acute nutritional ketosis. It remains to be investigated whether growth differentiation factor 15 (GDF-15)-an anorexigenic hormone-is involved in this process. The aim was to investigate the effect of a ketone ester beverage delivering β-hydroxybutyrate (KEβHB) on plasma levels of GDF-15, as well as assess the influence of eating behaviour on it. The study was a randomised controlled trial (registered at clinicaltrials.gov as NCT03889210). Individuals were given a KEβHB beverage or placebo in a cross-over fashion. Blood samples were collected at baseline, 30, 60, 90, 120, and 150 min after ingestion. Eating behaviour was assessed using the three-factor eating questionnaire. GDF-15 levels were not significantly different (p = 0.503) after the KEβHB beverage compared with the placebo. This finding remained consistent across the cognitive restraint, emotional eating, and uncontrolled eating domains. Changes in the anorexigenic hormone GDF-15, irrespective of eating behaviour, do not appear to play a major role in the glucose-lowering effect of exogenous ketones.
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Affiliation(s)
| | | | | | | | - Maxim S. Petrov
- School of Medicine, University of Auckland, Auckland 1010, New Zealand
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Stubbs BJ, Stephens EB, Senadheera C, Peralta S, Roa-Diaz S, Alexander L, Silverman-Martin W, Garcia TY, Yukawa M, Morris J, Blonquist TM, Johnson JB, Newman JC. Daily consumption of ketone ester, bis-octanoyl (R)-1,3-butanediol, is safe and tolerable in healthy older adults, a randomized, parallel arm, double-blind, placebo-controlled, pilot study. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.05.03.24306699. [PMID: 38746215 PMCID: PMC11092707 DOI: 10.1101/2024.05.03.24306699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Objectives Ketone bodies are endogenous metabolites produced during fasting or a ketogenic diet that have pleiotropic effects on aging pathways. Ketone esters (KEs) are compounds that induce ketosis without dietary changes, but KEs have not been studied in an older adult population. The primary objective of this trial was to determine tolerability and safety of KE ingestion in older adults. Design Randomized, placebo-controlled, double-blinded, parallel-arm trial, with a 12-week intervention period ( NCT05585762 ). Setting General community, Northern California, USA. Participants Community-dwelling older adults, independent in activities of daily living, with no unstable acute medical conditions (n=30) were randomized and n=23 (M= 14, F=9) completed the protocol. Intervention Participants were randomly allocated to consume either KE (bis-octanoyl (R)-1,3-butanediol) or a taste, appearance, and calorie-matched placebo (PLA) containing canola oil. Measurements Tolerability was assessed using a composite score from a daily log for 2-weeks, and then via a bi-weekly phone interview. Safety was assessed by vital signs and lab tests at screening and weeks 0, 4 and 12, along with tabulation of adverse events. Results There was no difference in the prespecified primary outcome of proportion of participants reporting moderate or severe nausea, headache, or dizziness on more than one day in a two-week reporting period (KE n =2 (14.3% [90% CI = 2.6 - 38.5]); PLA n=1 (7.1% [90% CI = 0.4 - 29.7]). Dropouts numbered four in the PLA group and two in the KE group. A greater number of symptoms were reported in both groups during the first two weeks; symptoms were reported less frequently between 2 - 12 weeks. There were no clinically relevant changes in safety labs or vital signs in either group. Conclusions This KE was safe and well-tolerated in healthy older adults. These results provide a foundation for use of KEs in aging research. Highlights Ketones esters induce ketosis without dietary changes and may target aging biologyStudies of ketone esters were limited in duration and focused on younger adultsWe found ketone esters were safe and tolerable for 12 weeks in healthy older adults.
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Gopalasingam N, Moeslund N, Christensen KH, Berg-Hansen K, Seefeldt J, Homilius C, Nielsen EN, Dollerup MR, Alstrup Olsen AK, Johannsen M, Boedtkjer E, Møller N, Eiskjær H, Gormsen LC, Nielsen R, Wiggers H. Enantiomer-Specific Cardiovascular Effects of the Ketone Body 3-Hydroxybutyrate. J Am Heart Assoc 2024; 13:e033628. [PMID: 38563382 DOI: 10.1161/jaha.123.033628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 02/16/2024] [Indexed: 04/04/2024]
Abstract
BACKGROUND The ketone body 3-hydroxybutyrate (3-OHB) increases cardiac output (CO) by 35% to 40% in healthy people and people with heart failure. The mechanisms underlying the effects of 3-OHB on myocardial contractility and loading conditions as well as the cardiovascular effects of its enantiomeric forms, D-3-OHB and L-3-OHB, remain undetermined. METHODS AND RESULTS Three groups of 8 pigs each underwent a randomized, crossover study. The groups received 3-hour infusions of either D/L-3-OHB (racemic mixture), 100% L-3-OHB, 100% D-3-OHB, versus an isovolumic control. The animals were monitored with pulmonary artery catheter, left ventricle pressure-volume catheter, and arterial and coronary sinus blood samples. Myocardial biopsies were evaluated with high-resolution respirometry, coronary arteries with isometric myography, and myocardial kinetics with D-[11C]3-OHB and L-[11C]3-OHB positron emission tomography. All three 3-OHB infusions increased 3-OHB levels (P<0.001). D/L-3-OHB and L-3-OHB increased CO by 2.7 L/min (P<0.003). D-3-OHB increased CO nonsignificantly (P=0.2). Circulating 3-OHB levels correlated with CO for both enantiomers (P<0.001). The CO increase was mediated through arterial elastance (afterload) reduction, whereas contractility and preload were unchanged. Ex vivo, D- and L-3-OHB dilated coronary arteries equally. The mitochondrial respiratory capacity remained unaffected. The myocardial 3-OHB extraction increased only during the D- and D/L-3-OHB infusions. D-[11C]3-OHB showed rapid cardiac uptake and metabolism, whereas L-[11C]3-OHB demonstrated much slower pharmacokinetics. CONCLUSIONS 3-OHB increased CO by reducing afterload. L-3-OHB exerted a stronger hemodynamic response than D-3-OHB due to higher circulating 3-OHB levels. There was a dissocitation between the myocardial metabolism and hemodynamic effects of the enantiomers, highlighting L-3-OHB as a potent cardiovascular agent with strong hemodynamic effects.
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Affiliation(s)
- Nigopan Gopalasingam
- Department of Cardiology Aarhus University Hospital Aarhus Denmark
- Department of Clinical Medicine Aarhus University Aarhus Denmark
- Department of Cardiology Gødstrup Hospital Herning Denmark
| | - Niels Moeslund
- Department of Clinical Medicine Aarhus University Aarhus Denmark
- Department of Heart, Lung and Vascular Surgery Aarhus University Hospital Aarhus Denmark
| | - Kristian Hylleberg Christensen
- Department of Cardiology Aarhus University Hospital Aarhus Denmark
- Department of Clinical Medicine Aarhus University Aarhus Denmark
| | - Kristoffer Berg-Hansen
- Department of Cardiology Aarhus University Hospital Aarhus Denmark
- Department of Clinical Medicine Aarhus University Aarhus Denmark
| | - Jacob Seefeldt
- Department of Cardiology Aarhus University Hospital Aarhus Denmark
- Department of Clinical Medicine Aarhus University Aarhus Denmark
| | | | - Erik Nguyen Nielsen
- Department of Nuclear Medicine and PET Aarhus University Hospital Aarhus Denmark
| | | | - Aage K Alstrup Olsen
- Department of Clinical Medicine Aarhus University Aarhus Denmark
- Department of Nuclear Medicine and PET Aarhus University Hospital Aarhus Denmark
| | - Mogens Johannsen
- Department of Forensic Medicine Aarhus University Aarhus Denmark
| | - Ebbe Boedtkjer
- Department of Biomedicine Aarhus University Aarhus Denmark
| | - Niels Møller
- Department of Endocrinology and Metabolism Aarhus University Aarhus Denmark
| | - Hans Eiskjær
- Department of Cardiology Aarhus University Hospital Aarhus Denmark
| | | | - Roni Nielsen
- Department of Cardiology Aarhus University Hospital Aarhus Denmark
| | - Henrik Wiggers
- Department of Cardiology Aarhus University Hospital Aarhus Denmark
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Quinones MD, Weiman K, Lemon PWR. Ketone Monoester Followed by Carbohydrate Ingestion after Glycogen-Lowering Exercise Does Not Improve Subsequent Endurance Cycle Time Trial Performance. Nutrients 2024; 16:932. [PMID: 38612966 PMCID: PMC11013615 DOI: 10.3390/nu16070932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
Relative to carbohydrate (CHO) alone, exogenous ketones followed by CHO supplementation during recovery from glycogen-lowering exercise have been shown to increase muscle glycogen resynthesis. However, whether this strategy improves subsequent exercise performance is unknown. The objective of this study was to assess the efficacy of ketone monoester (KME) followed by CHO ingestion after glycogen-lowering exercise on subsequent 20 km (TT20km) and 5 km (TT5km) best-effort time trials. Nine recreationally active men (175.6 ± 5.3 cm, 72.9 ± 7.7 kg, 28 ± 5 y, 12.2 ± 3.2% body fat, VO2max = 56.2 ± 5.8 mL· kg BM-1·min-1; mean ± SD) completed a glycogen-lowering exercise session, followed by 4 h of recovery and subsequent TT20km and TT5km. During the first 2 h of recovery, participants ingested either KME (25 g) followed by CHO at a rate of 1.2 g·kg-1·h-1 (KME + CHO) or an iso-energetic placebo (dextrose) followed by CHO (PLAC + CHO). Blood metabolites during recovery and performance during the subsequent two-time trials were measured. In comparison to PLAC + CHO, KME + CHO displayed greater (p < 0.05) blood beta-hydroxybutyrate concentration during the first 2 h, lower (p < 0.05) blood glucose concentrations at 30 and 60 min, as well as greater (p < 0.05) blood insulin concentration 2 h following ingestion. However, no treatment differences (p > 0.05) in power output nor time to complete either time trial were observed vs. PLAC + CHO. These data indicate that the metabolic changes induced by KME + CHO ingestion following glycogen-lowering exercise are insufficient to enhance subsequent endurance time trial performance.
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Affiliation(s)
| | | | - Peter W. R. Lemon
- Exercise Nutrition Research Laboratory, School of Kinesiology, The University of Western Ontario, London, ON N6A 3K7, Canada; (M.D.Q.); (K.W.)
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Neudorf H, Islam H, Falkenhain K, Oliveira B, Jackson GS, Moreno-Cabañas A, Madden K, Singer J, Walsh JJ, Little JP. Effect of the ketone beta-hydroxybutyrate on markers of inflammation and immune function in adults with type 2 diabetes. Clin Exp Immunol 2024; 216:89-103. [PMID: 38195093 PMCID: PMC10929696 DOI: 10.1093/cei/uxad138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/10/2023] [Accepted: 01/08/2024] [Indexed: 01/11/2024] Open
Abstract
Pre-clinical and cell culture evidence supports the role of the ketone beta-hydroxybutyrate (BHB) as an immunomodulatory molecule that may inhibit inflammatory signalling involved in several chronic diseases such as type 2 diabetes (T2D), but studies in humans are lacking. Therefore, we investigated the anti-inflammatory effect of BHB in humans across three clinical trials. To investigate if BHB suppressed pro-inflammatory cytokine secretion, we treated LPS-stimulated leukocytes from overnight-fasted adults at risk for T2D with BHB (Study 1). Next (Study 2), we investigated if exogenously raising BHB acutely in vivo by ketone monoester supplementation (KME) in adults with T2D would suppress pro-inflammatory plasma cytokines. In Study 3, we investigated the effect of BHB on inflammation via ex vivo treatment of LPS-stimulated leukocytes with BHB and in vivo thrice-daily pre-meal KME for 14 days in adults with T2D. Ex vivo treatment with BHB suppressed LPS-stimulated IL-1β, TNF-α, and IL-6 secretion and increased IL-1RA and IL-10 (Study 1). Plasma IL-10 increased by 90 min following ingestion of a single dose of KME in T2D, which corresponded to peak blood BHB (Study 2). Finally, 14 days of thrice-daily KME ingestion did not significantly alter plasma cytokines or leukocyte subsets including monocyte and T-cell polarization (Study 3). However, direct treatment of leukocytes with BHB modulated TNF-α, IL-1β, IFN-γ, and MCP-1 secretion in a time- and glucose-dependent manner (Study 3). Therefore, BHB appears to be anti-inflammatory in T2D, but this effect is transient and is modulated by the presence of disease, glycaemia, and exposure time.
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Affiliation(s)
- Helena Neudorf
- University of British Columbia Okanagan, School of Health and Exercise Sciences, Kelowna, BC, Canada
| | - Hashim Islam
- University of British Columbia Okanagan, School of Health and Exercise Sciences, Kelowna, BC, Canada
| | - Kaja Falkenhain
- University of British Columbia Okanagan, School of Health and Exercise Sciences, Kelowna, BC, Canada
| | - Barbara Oliveira
- University of British Columbia Okanagan, School of Health and Exercise Sciences, Kelowna, BC, Canada
| | - Garett S Jackson
- University of British Columbia Okanagan, School of Health and Exercise Sciences, Kelowna, BC, Canada
| | - Alfonso Moreno-Cabañas
- University of Castilla-La Mancha, Department of Sport Sciences, Exercise Physiology Lab at Toledo, Spain
| | - Kenneth Madden
- University of British Columbia, Department of Medicine, Centre of Aging SMART, Vancouver, BC, Canada
| | - Joel Singer
- University of British Columbia, School of Population and Public Health, Vancouver, BC,Canada
| | - Jeremy J Walsh
- McMaster University, Department of Kinesiology, Hamilton, ON, Canada
| | - Jonathan P Little
- University of British Columbia Okanagan, School of Health and Exercise Sciences, Kelowna, BC, Canada
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Soni S, Tabatabaei Dakhili SA, Ussher JR, Dyck JRB. The therapeutic potential of ketones in cardiometabolic disease: impact on heart and skeletal muscle. Am J Physiol Cell Physiol 2024; 326:C551-C566. [PMID: 38193855 PMCID: PMC11192481 DOI: 10.1152/ajpcell.00501.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 12/15/2023] [Accepted: 12/15/2023] [Indexed: 01/10/2024]
Abstract
β-Hydroxybutyrate (βOHB) is the major ketone in the body, and it is recognized as a metabolic energy source and an important signaling molecule. While ketone oxidation is essential in the brain during prolonged fasting/starvation, other organs such as skeletal muscle and the heart also use ketones as metabolic substrates. Additionally, βOHB-mediated molecular signaling events occur in heart and skeletal muscle cells, and via metabolism and/or signaling, ketones may contribute to optimal skeletal muscle health and cardiac function. Of importance, when the use of ketones for ATP production and/or as signaling molecules becomes disturbed in the presence of underlying obesity, type 2 diabetes, and/or cardiovascular diseases, these changes may contribute to cardiometabolic disease. As a result of these disturbances in cardiometabolic disease, multiple approaches have been used to elevate circulating ketones with the goal of optimizing either ketone metabolism or ketone-mediated signaling. These approaches have produced significant improvements in heart and skeletal muscle during cardiometabolic disease with a wide range of benefits that include improved metabolism, weight loss, better glycemic control, improved cardiac and vascular function, as well as reduced inflammation and oxidative stress. Herein, we present the evidence that indicates that ketone therapy could be used as an approach to help treat cardiometabolic diseases by targeting cardiac and skeletal muscles.
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Affiliation(s)
- Shubham Soni
- Cardiovascular Research Centre, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
- Department of Pediatrics, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Seyed Amirhossein Tabatabaei Dakhili
- Cardiovascular Research Centre, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - John R Ussher
- Cardiovascular Research Centre, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Jason R B Dyck
- Cardiovascular Research Centre, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
- Department of Pediatrics, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
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Falkenhain K, Oliveira BF, Islam H, Neudorf H, Cen HH, Johnson JD, Madden K, Singer J, Walsh JJ, Little JP. The effect of acute and 14-day exogenous ketone supplementation on glycemic control in adults with type 2 diabetes: two randomized controlled trials. Am J Physiol Endocrinol Metab 2024; 326:E61-E72. [PMID: 37991451 DOI: 10.1152/ajpendo.00332.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/02/2023] [Accepted: 11/17/2023] [Indexed: 11/23/2023]
Abstract
Acute ingestion of the exogenous ketone monoester supplement [(R)-3-hydroxybutyl-(R)-3-hydroxybutyrate] lowers blood glucose, suggesting therapeutic potential in individuals with impaired glucose metabolism. However, it is unknown how acute or repeated ingestion of exogenous ketones affects blood glucose control in individuals with type 2 diabetes (T2D). We conducted two randomized, counterbalanced, double-blind, placebo-controlled crossover trials to determine if 1) acute exogenous ketone monoester (0.3 g/kg body mass; N = 18) or 2) 14-day thrice daily premeal exogenous ketone monoester (15 g; N = 15) supplementation could lower blood glucose in individuals living with T2D. A single dose of the ketone monoester supplement elevated blood β-OHB to ∼2 mM. There were no differences in the primary outcomes of plasma glucose concentration (acutely) or serum fructosamine (glycemic control across 14 days) between conditions. Ketone monoester ingestion acutely increased insulin and lowered nonesterified fatty acid concentrations; plasma metabolomics confirmed a reduction in multiple free fatty acids species and select gluconeogenic amino acids. In contrast, no changes were observed in fasting metabolic outcomes following 14 days of supplementation. In the context of these randomized controlled trials, acute or repeated ketone monoester ingestion in adults with T2D did not lower blood glucose when consumed acutely in a fasted state and did not improve glycemic control following thrice daily premeal ingestion across 14 days. Future studies exploring the mechanistic basis for the (lack of) glucose-lowering effect of exogenous ketone supplementation in T2D and other populations are warranted.NEW & NOTEWORTHY Exogenous ketone supplements can acutely lower blood glucose, suggesting therapeutic potential in individuals with impaired glucose metabolism. However, the effect of exogenous ketones on glucose metabolism in adults with type 2 diabetes has not been investigated in a controlled setting. In adults with type 2 diabetes, ketone monoester ingestion did not lower blood glucose acutely in a fasted state and did not improve glycemic control across thrice daily premeal ingestion across 14 days.
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Affiliation(s)
- Kaja Falkenhain
- Faculty of Health and Social Development, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Barbara F Oliveira
- Faculty of Health and Social Development, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Hashim Islam
- Faculty of Health and Social Development, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Helena Neudorf
- Faculty of Health and Social Development, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Haoning H Cen
- Department of Cellular & Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - James D Johnson
- Department of Cellular & Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kenneth Madden
- Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Joel Singer
- Faculty of Medicine, School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jeremy J Walsh
- Department of Kinesiology, Faculty of Science, McMaster University, Hamilton, Ontario, Canada
| | - Jonathan P Little
- Faculty of Health and Social Development, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
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Marcotte-Chénard A, Tremblay R, Falkenhain K, Little JP, Riesco E. Effect of Acute and Chronic Ingestion of Exogenous Ketone Supplements on Blood Pressure: A Systematic Review and Meta-Analysis. J Diet Suppl 2023; 21:408-426. [PMID: 38145410 DOI: 10.1080/19390211.2023.2289961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2023]
Abstract
Exogenous ketone supplements have been suggested to have potential cardiovascular benefits, but their overall effect on blood pressure is unclear. Our objective was to perform a systematic review and meta-analysis on the effects of exogenous ketone supplements on blood pressure (BP) and concomitant changes in resting heart rate (HR). Five databases were searched on January 27th, 2023, for randomized and non-randomized studies. A random-effects model meta-analysis was performed including all studies jointly and separately for acute and chronic ingestion of ketone supplements. Out of 4012 studies identified in the search, 4 acute and 6 chronic studies with n = 187 participants were included. Pooled results (n = 10) showed no change in systolic (SMD [95% CI]= -0.14 [-0.40; 0.11]; I2= 30%; p = 0.17) or diastolic BP (-0.12 [-0.30; 0.05]; I2= 0%; p = 0.69), with a potential tendency observed toward increased resting heart rate (0.17 [-0.14; 0.47]; I2= 40%; p = 0.10). Similar results for systolic and diastolic BP were observed when assessing separately the effect of acute and chronic ingestion of ketone supplements (p ≥ 0.33). Supplement dosage was found to modulate the increase in resting heart rate (0.019 ± 0.006; p = 0.013; R2=100%), suggesting that higher supplement doses lead to a higher resting heart rate. Based on currently available data, acute or prolonged ingestion of ketone supplements does not seem to modulate BP. However, a tendency for HR to increase after acute ingestion was observed, particularly with higher doses. Higher quality studies with appropriate standardized measurements are needed to confirm these results.
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Affiliation(s)
- Alexis Marcotte-Chénard
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, Quebec, Canada
- Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, Quebec, Canada
| | - Renaud Tremblay
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, Quebec, Canada
- Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, Quebec, Canada
| | - Kaja Falkenhain
- School of Health and Exercise Sciences, The University of British Columbia, Okanagan Campus, Kelowna, British Columbia, Canada
| | - Jonathan P Little
- School of Health and Exercise Sciences, The University of British Columbia, Okanagan Campus, Kelowna, British Columbia, Canada
| | - Eléonor Riesco
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, Quebec, Canada
- Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, Quebec, Canada
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Stubbs BJ, Alvarez-Azanedo G, Peralta S, Roa-Diaz S, Gray W, Alexander L, Silverman-Martin W, Garcia T, Blonquist TM, Upadhyay V, Turnbaugh PJ, Johnson JB, Newman JC. Rationale and protocol for a safety, tolerability and feasibility randomized, parallel group, double-blind, placebo-controlled, pilot study of a novel ketone ester targeting frailty via immunometabolic geroscience mechanisms. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.10.25.23297571. [PMID: 37961234 PMCID: PMC10635199 DOI: 10.1101/2023.10.25.23297571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Background Frailty is a geriatric syndrome characterized by chronic inflammation and metabolic insufficiency that creates vulnerability to poor outcomes with aging. We hypothesize that geroscience interventions, which target mechanisms of aging, could ameliorate frailty. Metabolites such as ketone bodies are candidate geroscience interventions, having pleiotropic effects on inflammo-metabolic aging mechanisms. Ketone esters (KEs) induce ketosis without dietary changes, but KEs have not been studied in an older adult population. Our long-term goal is to examine if KEs modulate geroscience mechanisms and clinical outcomes relevant to frailty in older adults. Objectives The primary objective of this randomized, placebo-controlled, double-blinded, parallel-group, pilot trial is to determine tolerability of 12-weeks of KE ingestion in a generalizable population of older adults (≥ 65 years). Secondary outcomes include safety and acute blood ketone kinetics. Exploratory outcomes include physical function, cognitive function, quality of life, aging biomarkers and inflammatory measures. Methods Community-dwelling adults who are independent in activities of daily living, with no unstable acute medical conditions (n=30) will be recruited. The study intervention is a KE or a taste, appearance, and calorie matched placebo beverage. Initially, acute 4-hour ketone kinetics after 12.5g or 25g of KE consumption will be assessed. After collection of baseline safety, functional, and biological measurements, subjects will randomly be allocated to consume KE 25g or placebo once daily for 12-weeks. Questionnaires will assess tolerability daily for 2-weeks, and then via phone interview at bi-monthly intervals. Safety assessments will be repeated at week 4. All measures will be repeated at week 12. Conclusion This study will evaluate feasibility, tolerability, and safety of KE consumption in older adults and provide exploratory data across a range of geroscience-related endpoints. This data will inform design of larger trials to rigorously test KE effects on geroscience mechanisms and clinical outcomes relevant to frailty.
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Affiliation(s)
| | | | | | | | - Wyatt Gray
- Buck Institute for Research on Aging, Novato, CA, USA
| | | | | | - Thelma Garcia
- Buck Institute for Research on Aging, Novato, CA, USA
| | | | - Vaibhav Upadhyay
- Department of Microbiology & Immunology, UCSF, San Francisco, CA, USA 94143
- Department of Medicine, UCSF, San Francisco California, USA
| | - Peter J. Turnbaugh
- Department of Microbiology & Immunology, UCSF, San Francisco, CA, USA 94143
- Chan Zuckerberg Biohub-San Francisco, San Francisco, CA, USA 94158
| | | | - John C. Newman
- Buck Institute for Research on Aging, Novato, CA, USA
- Division of Geriatrics, UCSF, San Francisco, California, USA
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Bae J, Lee BW. Association between Impaired Ketogenesis and Metabolic-Associated Fatty Liver Disease. Biomolecules 2023; 13:1506. [PMID: 37892188 PMCID: PMC10604525 DOI: 10.3390/biom13101506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/26/2023] [Accepted: 10/06/2023] [Indexed: 10/29/2023] Open
Abstract
Metabolic (dysfunction) associated fatty liver disease (MAFLD) is generally developed with excessive accumulation of lipids in the liver. Ketogenesis is an efficient pathway for the disposal of fatty acids in the liver and its metabolic benefits have been reported. In this review, we examined previous studies on the association between ketogenesis and MAFLD and reviewed the candidate mechanisms that can explain this association.
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Affiliation(s)
- Jaehyun Bae
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Catholic Kwandong University College of Medicine, International St. Mary’s Hospital, Incheon 22711, Republic of Korea
| | - Byung-Wan Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
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Mah E, Blonquist TM, Kaden VN, Beckman D, Boileau AC, Anthony JC, Stubbs BJ. A randomized, open-label, parallel pilot study investigating metabolic product kinetics of the novel ketone ester, bis-hexanoyl (R)-1,3-butanediol, over one week of ingestion in healthy adults. Front Physiol 2023; 14:1196535. [PMID: 37427402 PMCID: PMC10324611 DOI: 10.3389/fphys.2023.1196535] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 06/09/2023] [Indexed: 07/11/2023] Open
Abstract
Introduction: Bis-hexanoyl (R)-1,3-butanediol (BH-BD) is a novel ketone ester that, when consumed, is hydrolyzed into hexanoic acid (HEX) and (R)-1,3-butanediol (BDO) which are subsequently metabolized into beta-hydroxybutyrate (BHB). Methods: We undertook a randomized, parallel, open-label study in healthy adults (n = 33) to elucidate blood BHB, HEX and BDO concentrations for 8 h following consumption of three different serving sizes (SS) of BH-BD (12.5, 25 and 50 g/day) before (Day 0) and after 7 days of daily BH-BD consumption (Day 7). Results: Maximal concentration and area under the curve of all metabolites increased proportionally to SS and were greatest for BHB followed by BDO then HEX on both Day 0 and 7. Metabolite half-life tended to decrease with increasing SS for BHB and HEX. Time to peak concentration increased with increasing SS for BHB and BDO on both days. In vitro incubation of BH-BD in human plasma demonstrated BH-BD undergoes rapid spontaneous hydrolysis. Conclusion: These results demonstrate that orally ingested BH-BD is hydrolyzed into products that appear in the plasma and undergo conversion to BHB in a SS dependent manner, and that metabolism of BH-BD neither becomes saturated at serving sizes up to 50 g nor displays consistent adaptation after 7 days of daily consumption.
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Affiliation(s)
- Eunice Mah
- Biofortis, Mérieux NutriSciences, Addison, IL, United States
| | | | | | - Dawn Beckman
- Biofortis, Mérieux NutriSciences, Addison, IL, United States
| | | | | | - Brianna J. Stubbs
- BHB Therapeutics Ltd., Dublin, Ireland
- Buck Institute for Research on Aging, Novato, CA, United States
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12
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Zhang Y, Li Z, Liu X, Chen X, Zhang S, Chen Y, Chen J, Chen J, Wu F, Chen GQ. 3-Hydroxybutyrate ameliorates insulin resistance by inhibiting PPARγ Ser273 phosphorylation in type 2 diabetic mice. Signal Transduct Target Ther 2023; 8:190. [PMID: 37230992 DOI: 10.1038/s41392-023-01415-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 03/01/2023] [Accepted: 03/19/2023] [Indexed: 05/27/2023] Open
Abstract
3-Hydroxybutyrate (3HB) is a small ketone body molecule produced endogenously by the body in the liver. Previous studies have shown that 3HB can reduce blood glucose level in type 2 diabetic (T2D) patients. However, there is no systematic study and clear mechanism to evaluate and explain the hypoglycemic effect of 3HB. Here we demonstrate that 3HB reduces fasting blood glucose level, improves glucose tolerance, and ameliorates insulin resistance in type 2 diabetic mice through hydroxycarboxylic acid receptor 2 (HCAR2). Mechanistically, 3HB increases intracellular calcium ion (Ca2+) levels by activating HCAR2, thereby stimulating adenylate cyclase (AC) to increase cyclic adenosine monophosphate (cAMP) concentration, and then activating protein kinase A (PKA). Activated PKA inhibits Raf1 proto-oncogene serine/threonine-protein kinase (Raf1) activity, resulting in a decrease in extracellular signal-regulated kinases 1/2 (ERK1/2) activity and ultimately inhibiting peroxisome proliferator-activated receptor γ (PPARγ) Ser273 phosphorylation in adipocytes. Inhibition of PPARγ Ser273 phosphorylation by 3HB altered the expression of PPARγ regulated genes and reduced insulin resistance. Collectively, 3HB ameliorates insulin resistance in type 2 diabetic mice through a pathway of HCAR2/Ca2+/cAMP/PKA/Raf1/ERK1/2/PPARγ.
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Affiliation(s)
- Yudian Zhang
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China
| | - Zihua Li
- Department of Medical Genetics and Cell Biology, School of Basic Medical Science of Ningxia Medical University, Yinchuan, Ningxia, 750004, P. R. China
| | - Xinyi Liu
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China
| | - Xinyu Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China
| | - Shujie Zhang
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China
| | - Yuemeng Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China
| | - Jiangnan Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China
| | - Jin Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China
| | - Fuqing Wu
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China
| | - Guo-Qiang Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, P. R. China.
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing, 100084, China.
- MOE Key Lab of Industrial Biocatalysis, Dept of Chemical Engineering, Tsinghua University, Beijing, 100084, P. R. China.
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13
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Liu Y, Bharmal SH, Kimita W, Petrov MS. Effect of d-β-Hydroxybutyrate-(R)-1,3 Butanediol on Appetite Regulation in People with Prediabetes. Mol Nutr Food Res 2023; 67:e2200615. [PMID: 36565045 DOI: 10.1002/mnfr.202200615] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/22/2022] [Indexed: 12/25/2022]
Abstract
SCOPE The main aim of the present study is to study the effect of acute ketosis on parameters of appetite regulation in prediabetes. METHODS AND RESULTS This is a randomized controlled trial registered under ClinicalTrials.gov identifier NCT03889210. After an overnight fast, 18 adults with prediabetes are assigned to consume a ketone monoester (d-β-hydroxybutyrate-(R)-1,3 butanediol) drink and a placebo drink in cross-over fashion. Blood samples are collected every 30 min, from baseline to 150 min. Paired t test is used to compare the total area under the curve (AUC) for the changes in parameters of appetite regulation (acylated ghrelin, peptide YY [PYY], and hunger) following both drinks. Significant elevation in blood β-hydroxybutyrate from 0.2 to 3.5 mmol L-1 (p < 0.001) is achieved within 30 min. Acute ketosis does not result in statistically significant differences in the AUCs for ghrelin, PYY, and hunger. CONCLUSION Acute ketosis consistently does not affect both objective and subjective parameters of appetite regulation in prediabetes.
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Affiliation(s)
- Yutong Liu
- School of Medicine, University of Auckland, Auckland, 1023, New Zealand
| | - Sakina H Bharmal
- School of Medicine, University of Auckland, Auckland, 1023, New Zealand
| | - Wandia Kimita
- School of Medicine, University of Auckland, Auckland, 1023, New Zealand
| | - Maxim S Petrov
- School of Medicine, University of Auckland, Auckland, 1023, New Zealand
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14
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Falkenhain K, Islam H, Little JP. Exogenous ketone supplementation: an emerging tool for physiologists with potential as a metabolic therapy. Exp Physiol 2023; 108:177-187. [PMID: 36533967 PMCID: PMC10103874 DOI: 10.1113/ep090430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022]
Abstract
NEW FINDINGS What is the topic of this review? The integrative physiological response to exogenous ketone supplementation. What advances does it highlight? The physiological effects and therapeutic potential of exogenous ketones on metabolic health, cardiovascular function, cognitive processing, and modulation of inflammatory pathways and immune function. Also highlighted are current challenges and future directions of the field. ABSTRACT Exogenous oral ketone supplements, primarily in form of ketone salts or esters, have emerged as a useful research tool for manipulating metabolism with potential therapeutic application targeting various aspects of several common chronic diseases. Recent literature has investigated the effects of exogenously induced ketosis on metabolic health, cardiovascular function, cognitive processing, and modulation of inflammatory pathways and immune function. This narrative review provides an overview of the integrative physiological effects of exogenous ketone supplementation and highlights current challenges and future research directions. Much of the existing research on therapeutic applications - particularly mechanistic studies - has involved pre-clinical rodent and/or cellular models, requiring further validation in human clinical studies. Existing human studies report that exogenous ketones can lower blood glucose and improve some aspects of cognitive function, highlighting the potential therapeutic application of exogenous ketones for type 2 diabetes and neurological diseases. There is also support for the ability of exogenous ketosis to improve cardiac metabolism in rodent models of heart failure with supporting human studies emerging; long-terms effects of exogenous ketone supplementation on the human cardiovascular system and lipid profiles are needed. An important avenue for future work is provided by research accelerating technologies that enable continuous ketone monitoring and/or the development of more palatable ketone mixtures that optimize plasma ketone kinetics to enable sustained ketosis. Lastly, research exploring the physiological interactions between exogenous ketones and varying metabolic states (e.g., exercise, fasting, metabolic disease) should yield important insights that can be used to maximize the health benefits of exogenous ketosis.
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Affiliation(s)
- Kaja Falkenhain
- School of Health and Exercise SciencesUniversity of British Columbia OkanaganKelownaBritish ColumbiaCanada
| | - Hashim Islam
- School of Health and Exercise SciencesUniversity of British Columbia OkanaganKelownaBritish ColumbiaCanada
| | - Jonathan P. Little
- School of Health and Exercise SciencesUniversity of British Columbia OkanaganKelownaBritish ColumbiaCanada
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15
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Costa TJ, Linder BA, Hester S, Fontes M, Pernomian L, Wenceslau CF, Robinson AT, McCarthy CG. The janus face of ketone bodies in hypertension. J Hypertens 2022; 40:2111-2119. [PMID: 35969209 PMCID: PMC9733433 DOI: 10.1097/hjh.0000000000003243] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hypertension is the most important risk factor for the development of terminal cardiovascular diseases, such as heart failure, chronic kidney disease, and atherosclerosis. Lifestyle interventions to lower blood pressure are generally desirable prior to initiating pharmaceutical drug treatments, which may have undesirable side effects. Ketogenic interventions are popular but the scientific literature supporting their efficacy is specific to certain interventions and outcomes in animal models and patient populations. For example, although caloric restriction has its own inherent difficulties (e.g. it requires high levels of motivation and adherence is difficult), it has unequivocally been associated with lowering blood pressure in hypertensive patients. On the other hand, the antihypertensive efficacy of ketogenic diets is inconclusive, and this is surprising, given that these diets have been largely helpful in mitigating metabolic syndrome and promoting longevity. It is possible that side effects associated with ketogenic diets (e.g. dyslipidemia) aggravate the hypertensive phenotype. However, given the recent data from our group, and others, reporting that the most abundant ketone body, β-hydroxybutyrate, can have positive effects on endothelial and vascular health, there is hope that ketone bodies can be harnessed as a therapeutic strategy to combat hypertension. Therefore, we conclude this review with a summary of the type and efficacy of ketone supplements. We propose that ketone supplements warrant investigation as low-dose antihypertensive therapy that decreases total peripheral resistance with minimal adverse side effects.
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Affiliation(s)
- Tiago J. Costa
- Cardiovascular Translational Research Center, University of South Carolina School of Medicine, Columbia, South Carolina
- Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, South Carolina
| | | | - Seth Hester
- Cardiovascular Translational Research Center, University of South Carolina School of Medicine, Columbia, South Carolina
- Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, South Carolina
| | - Milene Fontes
- Cardiovascular Translational Research Center, University of South Carolina School of Medicine, Columbia, South Carolina
- Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, South Carolina
| | - Laena Pernomian
- Cardiovascular Translational Research Center, University of South Carolina School of Medicine, Columbia, South Carolina
- Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, South Carolina
| | - Camilla F. Wenceslau
- Cardiovascular Translational Research Center, University of South Carolina School of Medicine, Columbia, South Carolina
- Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, South Carolina
| | | | - Cameron G. McCarthy
- Cardiovascular Translational Research Center, University of South Carolina School of Medicine, Columbia, South Carolina
- Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, South Carolina
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16
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Falkenhain K, Daraei A, Forbes SC, Little JP. Effects of Exogenous Ketone Supplementation on Blood Glucose: A Systematic Review and Meta-analysis. Adv Nutr 2022; 13:1697-1714. [PMID: 35380602 PMCID: PMC9526861 DOI: 10.1093/advances/nmac036] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 03/04/2022] [Accepted: 04/01/2022] [Indexed: 01/28/2023] Open
Abstract
Recently developed ketone (monoester or salt) supplements acutely elevate blood β-hydroxybutyrate (BHB) exogenously without prolonged periods of fasting or carbohydrate restriction. Previous (small-scale) studies have found a blood glucose-lowering effect of exogenous ketones. This study aimed to systematically review available evidence and conduct meta-analyses of studies reporting on exogenous ketones and blood glucose. We searched 6 electronic databases on 13 December 2021 for randomized and nonrandomized trials of any length that reported on the use of exogenous ketones. We calculated raw mean differences (MDs) in blood BHB and glucose in 2 main analyses: 1) after compared with before acute ingestion of exogenous ketones and 2) following acute ingestion of exogenous ketones compared with a comparator supplement. We pooled effect sizes using random-effects models and performed prespecified subgroup analyses to examine the effect of potential explanatory factors, including study population, exercise, blood BHB, and supplement type, dosing, and timing. Risk of bias was examined using Cochrane's risk-of-bias tools. Studies that could not be meta-analyzed were summarized narratively. Forty-three trials including 586 participants are summarized in this review. Following ingestion, exogenous ketones increased blood BHB (MD = 1.73 mM; 95% CI: 1.26, 2.21 mM; P < 0.001) and decreased mean blood glucose (MD = -0.54 mM; 95% CI: -0.68, -0.40 mM; P < 0.001). Similarly, when compared with placebo, blood BHB increased (MD = 1.98 mM; 95% CI: 1.52, 2.45 mM; P < 0.001) and blood glucose decreased (MD = -0.47 mM; 95% CI: -0.57, -0.36 mM; P < 0.001). Across both analyses, significantly greater effects were seen with ketone monoesters compared with salts (P < 0.001). The available evidence indicates that acute ingestion of exogenous ketones leads to increased blood BHB and decreased blood glucose. Limited evidence on prolonged ketone supplementation was found.
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Affiliation(s)
| | - Ali Daraei
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Scott C Forbes
- Department of Physical Education Studies, Faculty of Education, Brandon University, Brandon, Manitoba, Canada
| | - Jonathan P Little
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
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17
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Soto‐Mota A, Norwitz NG, Evans RD, Clarke K. Exogenous
d
‐β‐hydroxybutyrate lowers blood glucose in part by decreasing the availability of L‐alanine for gluconeogenesis. Endocrinol Diabetes Metab 2022; 5:e00300. [PMID: 34787952 PMCID: PMC8754249 DOI: 10.1002/edm2.300] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 09/08/2021] [Accepted: 09/11/2021] [Indexed: 12/28/2022] Open
Abstract
Background Interventions that induce ketosis simultaneously lower blood glucose and the explanation for this phenomenon is unknown. Additionally, the glucose‐lowering effect of acute ketosis is greater in people with type 2 diabetes (T2D). On the contrary, L‐alanine is a gluconeogenic substrate secreted by skeletal muscle at higher levels in people with T2D and infusing of ketones lower circulating L‐alanine blood levels. In this study, we sought to determine whether supplementation with L‐alanine would attenuate the glucose‐lowering effect of exogenous ketosis using a ketone ester (KE). Methods This crossover study involved 10 healthy human volunteers who fasted for 24 h prior to the ingestion of 25 g of d‐β‐hydroxybutyrate (βHB) in the form of a KE drink (ΔG®) on two separate visits. During one of the visits, participants additionally ingested 2 g of L‐alanine to see whether L‐alanine supplementation would attenuate the glucose‐lowering effect of the KE drink. Blood L‐alanine, L‐glutamine, glucose, βHB, free fatty acids (FFA), lactate and C‐peptide were measured for 120 min after ingestion of the KE, with or without L‐alanine. Findings The KE drinks elevated blood βHB concentrations from negligible levels to 4.52 ± 1.23 mmol/L, lowered glucose from 4.97 ± SD 0.39 to 3.77 ± SD 0.40 mmol/L, and lowered and L‐alanine from 0.56 ± SD 0.88 to 0.41 ± SD 0.91 mmol/L. L‐alanine in the KE drink elevated blood L‐Alanine by 0.68 ± SD 0.15 mmol/L, but had no significant effect on blood βHB, L‐glutamine, FFA, lactate, nor C‐peptide concentrations. By contrast, L‐alanine supplementation significantly attenuated the ketosis‐induced drop in glucose from 28% ± SD 8% to 16% ± SD 7% (p < .01). Conclusions The glucose‐lowering effect of acutely elevated βHB is partially due to βHB decreasing L‐alanine availability as a substrate for gluconeogenesis.
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Affiliation(s)
- Adrian Soto‐Mota
- Department of Physiology, Anatomy and Genetics University of Oxford Oxford UK
| | - Nicholas G. Norwitz
- Department of Physiology, Anatomy and Genetics University of Oxford Oxford UK
| | - Rhys D. Evans
- Department of Physiology, Anatomy and Genetics University of Oxford Oxford UK
| | - Kieran Clarke
- Department of Physiology, Anatomy and Genetics University of Oxford Oxford UK
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18
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Exogenous Ketone Supplements in Athletic Contexts: Past, Present, and Future. Sports Med 2022; 52:25-67. [PMID: 36214993 PMCID: PMC9734240 DOI: 10.1007/s40279-022-01756-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/23/2022] [Indexed: 12/15/2022]
Abstract
The ketone bodies acetoacetate (AcAc) and β-hydroxybutyrate (βHB) have pleiotropic effects in multiple organs including brain, heart, and skeletal muscle by serving as an alternative substrate for energy provision, and by modulating inflammation, oxidative stress, catabolic processes, and gene expression. Of particular relevance to athletes are the metabolic actions of ketone bodies to alter substrate utilisation through attenuating glucose utilisation in peripheral tissues, anti-lipolytic effects on adipose tissue, and attenuation of proteolysis in skeletal muscle. There has been long-standing interest in the development of ingestible forms of ketone bodies that has recently resulted in the commercial availability of exogenous ketone supplements (EKS). These supplements in the form of ketone salts and ketone esters, in addition to ketogenic compounds such as 1,3-butanediol and medium chain triglycerides, facilitate an acute transient increase in circulating AcAc and βHB concentrations, which has been termed 'acute nutritional ketosis' or 'intermittent exogenous ketosis'. Some studies have suggested beneficial effects of EKS to endurance performance, recovery, and overreaching, although many studies have failed to observe benefits of acute nutritional ketosis on performance or recovery. The present review explores the rationale and historical development of EKS, the mechanistic basis for their proposed effects, both positive and negative, and evidence to date for their effects on exercise performance and recovery outcomes before concluding with a discussion of methodological considerations and future directions in this field.
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19
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Kovács Z, Brunner B, Ari C. Beneficial Effects of Exogenous Ketogenic Supplements on Aging Processes and Age-Related Neurodegenerative Diseases. Nutrients 2021; 13:nu13072197. [PMID: 34206738 PMCID: PMC8308443 DOI: 10.3390/nu13072197] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 12/20/2022] Open
Abstract
Life expectancy of humans has increased continuously up to the present days, but their health status (healthspan) was not enhanced by similar extent. To decrease enormous medical, economical and psychological burden that arise from this discrepancy, improvement of healthspan is needed that leads to delaying both aging processes and development of age-related diseases, thereby extending lifespan. Thus, development of new therapeutic tools to alleviate aging processes and related diseases and to increase life expectancy is a topic of increasing interest. It is widely accepted that ketosis (increased blood ketone body levels, e.g., β-hydroxybutyrate) can generate neuroprotective effects. Ketosis-evoked neuroprotective effects may lead to improvement in health status and delay both aging and the development of related diseases through improving mitochondrial function, antioxidant and anti-inflammatory effects, histone and non-histone acetylation, β-hydroxybutyrylation of histones, modulation of neurotransmitter systems and RNA functions. Administration of exogenous ketogenic supplements was proven to be an effective method to induce and maintain a healthy state of nutritional ketosis. Consequently, exogenous ketogenic supplements, such as ketone salts and ketone esters, may mitigate aging processes, delay the onset of age-associated diseases and extend lifespan through ketosis. The aim of this review is to summarize the main hallmarks of aging processes and certain signaling pathways in association with (putative) beneficial influences of exogenous ketogenic supplements-evoked ketosis on lifespan, aging processes, the most common age-related neurodegenerative diseases (Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis), as well as impaired learning and memory functions.
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Affiliation(s)
- Zsolt Kovács
- Department of Biology, Savaria University Centre, ELTE Eötvös Loránd University, Károlyi Gáspár tér 4., 9700 Szombathely, Hungary; (Z.K.); (B.B.)
| | - Brigitta Brunner
- Department of Biology, Savaria University Centre, ELTE Eötvös Loránd University, Károlyi Gáspár tér 4., 9700 Szombathely, Hungary; (Z.K.); (B.B.)
- Faculty of Sciences, Institute of Biology, University of Pécs, Ifjúság Str. 6, 7624 Pécs, Hungary
| | - Csilla Ari
- Behavioral Neuroscience Research Laboratory, Department of Psychology, University of South Florida, 4202 E. Fowler Ave, PCD 3127, Tampa, FL 33620, USA
- Ketone Technologies LLC, 2780 E. Fowler Ave. #226, Tampa, FL 33612, USA
- Correspondence: ; Tel.: +1-(813)-2409925
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