1
|
Ruppert PMM, Kersten S. Mechanisms of hepatic fatty acid oxidation and ketogenesis during fasting. Trends Endocrinol Metab 2024; 35:107-124. [PMID: 37940485 DOI: 10.1016/j.tem.2023.10.002] [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: 08/31/2023] [Revised: 10/02/2023] [Accepted: 10/04/2023] [Indexed: 11/10/2023]
Abstract
Fasting is part of many weight management and health-boosting regimens. Fasting causes substantial metabolic adaptations in the liver that include the stimulation of fatty acid oxidation and ketogenesis. The induction of fatty acid oxidation and ketogenesis during fasting is mainly driven by interrelated changes in plasma levels of various hormones and an increase in plasma nonesterified fatty acid (NEFA) levels and is mediated transcriptionally by the peroxisome proliferator-activated receptor (PPAR)α, supported by CREB3L3 (cyclic AMP-responsive element-binding protein 3 like 3). Compared with men, women exhibit higher ketone levels during fasting, likely due to higher NEFA availability, suggesting that the metabolic response to fasting shows sexual dimorphism. Here, we synthesize the current molecular knowledge on the impact of fasting on hepatic fatty acid oxidation and ketogenesis.
Collapse
Affiliation(s)
- Philip M M Ruppert
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5000 C Odense, Denmark
| | - Sander Kersten
- Nutrition, Metabolism, and Genomics Group, Division of Human Nutrition and Health, Wageningen University, 6708 WE Wageningen, The Netherlands; Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
| |
Collapse
|
2
|
Hong BV, Rhodes CH, Agus JK, Tang X, Zhu C, Zheng JJ, Zivkovic AM. A single 36-h water-only fast vastly remodels the plasma lipidome. Front Cardiovasc Med 2023; 10:1251122. [PMID: 37745091 PMCID: PMC10513913 DOI: 10.3389/fcvm.2023.1251122] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 08/21/2023] [Indexed: 09/26/2023] Open
Abstract
Background Prolonged fasting, characterized by restricting caloric intake for 24 h or more, has garnered attention as a nutritional approach to improve lifespan and support healthy aging. Previous research from our group showed that a single bout of 36-h water-only fasting in humans resulted in a distinct metabolomic signature in plasma and increased levels of bioactive metabolites, which improved macrophage function and lifespan in C. elegans. Objective This secondary outcome analysis aimed to investigate changes in the plasma lipidome associated with prolonged fasting and explore any potential links with markers of cardiometabolic health and aging. Method We conducted a controlled pilot study with 20 male and female participants (mean age, 27.5 ± 4.4 years; mean BMI, 24.3 ± 3.1 kg/m2) in four metabolic states: (1) overnight fasted (baseline), (2) 2-h postprandial fed state (fed), (3) 36-h fasted state (fasted), and (4) 2-h postprandial refed state 12 h after the 36-h fast (refed). Plasma lipidomic profiles were analyzed using liquid chromatography and electrospray ionization mass spectrometry. Results Several lipid classes, including lysophosphatidylcholine (LPC), lysophosphatidylethanolamine (LPE), phosphatidylethanolamine, and triacylglycerol were significantly reduced in the 36-h fasted state, while free fatty acids, ceramides, and sphingomyelin were significantly increased compared to overnight fast and fed states (P < 0.05). After correction for multiple testing, 245 out of 832 lipid species were significantly altered in the fasted state compared to baseline (P < 0.05). Random forest models revealed that several lipid species, such as LPE(18:1), LPC(18:2), and FFA(20:1) were important features in discriminating the fasted state from both the overnight fasted and postprandial state. Conclusion Our findings indicate that prolonged fasting vastly remodels the plasma lipidome and markedly alters the concentrations of several lipid species, which may be sensitive biomarkers of prolonged fasting. These changes in lipid metabolism during prolonged fasting have important implications for the management of cardiometabolic health and healthy aging, and warrant further exploration and validation in larger cohorts and different population groups.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Angela M. Zivkovic
- Department of Nutrition, University of California, Davis, Davis, CA, United States
| |
Collapse
|
3
|
Parker J. Pathophysiological Effects of Contemporary Lifestyle on Evolutionary-Conserved Survival Mechanisms in Polycystic Ovary Syndrome. Life (Basel) 2023; 13:life13041056. [PMID: 37109585 PMCID: PMC10145572 DOI: 10.3390/life13041056] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 04/15/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Polycystic ovary syndrome (PCOS) is increasingly being characterized as an evolutionary mismatch disorder that presents with a complex mixture of metabolic and endocrine symptoms. The Evolutionary Model proposes that PCOS arises from a collection of inherited polymorphisms that have been consistently demonstrated in a variety of ethnic groups and races. In utero developmental programming of susceptible genomic variants are thought to predispose the offspring to develop PCOS. Postnatal exposure to lifestyle and environmental risk factors results in epigenetic activation of developmentally programmed genes and disturbance of the hallmarks of health. The resulting pathophysiological changes represent the consequences of poor-quality diet, sedentary behaviour, endocrine disrupting chemicals, stress, circadian disruption, and other lifestyle factors. Emerging evidence suggests that lifestyle-induced gastrointestinal dysbiosis plays a central role in the pathogenesis of PCOS. Lifestyle and environmental exposures initiate changes that result in disturbance of the gastrointestinal microbiome (dysbiosis), immune dysregulation (chronic inflammation), altered metabolism (insulin resistance), endocrine and reproductive imbalance (hyperandrogenism), and central nervous system dysfunction (neuroendocrine and autonomic nervous system). PCOS can be a progressive metabolic condition that leads to obesity, gestational diabetes, type two diabetes, metabolic-associated fatty liver disease, metabolic syndrome, cardiovascular disease, and cancer. This review explores the mechanisms that underpin the evolutionary mismatch between ancient survival pathways and contemporary lifestyle factors involved in the pathogenesis and pathophysiology of PCOS.
Collapse
Affiliation(s)
- Jim Parker
- School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia
| |
Collapse
|
4
|
Stratton MT, Albracht-Schulte K, Harty PS, Siedler MR, Rodriguez C, Tinsley GM. Physiological responses to acute fasting: implications for intermittent fasting programs. Nutr Rev 2022; 80:439-452. [PMID: 35142356 DOI: 10.1093/nutrit/nuab094] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intermittent fasting (IF) is a dietary strategy that involves alternating periods of abstention from calorie consumption with periods of ad libitum food intake. There is significant interest in the body of literature describing longitudinal adaptations to IF. Less attention has been given to the acute physiological responses that occur during the fasting durations that are commonly employed by IF practitioners. Thus, the purpose of this review was to examine the physiological responses - including alterations in substrate metabolism, systemic hormones, and autophagy - that occur throughout an acute fast. Literature searches were performed to locate relevant research describing physiological responses to acute fasting and short-term starvation. A single fast demonstrated the ability to alter glucose and lipid metabolism within the initial 24 hours, but variations in protein metabolism appeared to be minimal within this time frame. The ability of an acute fast to elicit significant increases in autophagy is still unknown. The information summarized in this review can be used to help contextualize existing research and better inform development of future IF interventions.
Collapse
Affiliation(s)
- Matthew T Stratton
- Energy Balance and Body Composition Laboratory; Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, Texas, USA
| | - Kembra Albracht-Schulte
- Energy Balance and Body Composition Laboratory; Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, Texas, USA
| | - Patrick S Harty
- Energy Balance and Body Composition Laboratory; Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, Texas, USA
| | - Madelin R Siedler
- Energy Balance and Body Composition Laboratory; Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, Texas, USA
| | - Christian Rodriguez
- Energy Balance and Body Composition Laboratory; Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, Texas, USA
| | - Grant M Tinsley
- Energy Balance and Body Composition Laboratory; Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, Texas, USA
| |
Collapse
|
5
|
Small SD, Margolis LM. Impact of Dietary Carbohydrate Restriction versus Energy Restriction on Exogenous Carbohydrate Oxidation during Aerobic Exercise. Adv Nutr 2021; 13:S2161-8313(22)00076-X. [PMID: 34788795 PMCID: PMC8970824 DOI: 10.1093/advances/nmab124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Individuals with high physical activity levels, such as athletes and military personnel, are likely to experience periods of low muscle glycogen content. Reductions in glycogen stores are associated with impaired physical performance. Lower glycogen stores in these populations are likely due to sustained aerobic exercise coupled with sub-optimal carbohydrate or energy intake. Consuming exogenous carbohydrate during aerobic exercise may be an effective intervention to sustain physical performance during periods of low glycogen. However, research is limited in the area of carbohydrate recommendations to fuel performance during periods of sub-optimal carbohydrate and energy intake. Additionally, the studies that have investigated the effects of low glycogen stores on exogenous carbohydrate oxidation have yielded conflicting results. Discrepancies between studies may be the result of glycogen stores being lowered by restricting carbohydrate or restricting energy intake. This narrative review discusses the influence of low glycogen status resulting from carbohydrate restriction versus energy restriction on exogenous carbohydrate oxidation and examines the potential mechanism resulting in divergent responses in exogenous carbohydrate oxidation. Results from this review indicate that rates of exogenous carbohydrate oxidation can be maintained when glycogen content is lower following carbohydrate restrictions, but may be reduced following energy restriction. Reductions in exogenous carbohydrate oxidation following energy restriction appear to result from lower insulin sensitivity and glucose uptake. Exogenous carbohydrate may thus be an effective intervention to sustain performance following short-term energy adequate carbohydrate restriction, but may not be an effective ergogenic aid when glycogen stores are low due to energy restriction.
Collapse
Affiliation(s)
- Stephanie D Small
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA,Oak Ridge Institute of Science and Education, Oak Ridge, TN, USA
| | | |
Collapse
|
6
|
de Vasconcelos DAA, Giesbertz P, de Souza DR, Vitzel KF, Abreu P, Marzuca-Nassr GN, Fortes MAS, Murata GM, Hirabara SM, Curi R, Daniel H, Pithon-Curi TC. Oral L-glutamine pretreatment attenuates skeletal muscle atrophy induced by 24-h fasting in mice. J Nutr Biochem 2019; 70:202-214. [DOI: 10.1016/j.jnutbio.2019.05.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/23/2019] [Accepted: 05/14/2019] [Indexed: 02/06/2023]
|
7
|
Harney DJ, Hutchison AT, Hatchwell L, Humphrey SJ, James DE, Hocking S, Heilbronn LK, Larance M. Proteomic Analysis of Human Plasma during Intermittent Fasting. J Proteome Res 2019; 18:2228-2240. [PMID: 30892045 PMCID: PMC6503536 DOI: 10.1021/acs.jproteome.9b00090] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Intermittent fasting (IF) increases lifespan and decreases metabolic disease phenotypes and cancer risk in model organisms, but the health benefits of IF in humans are less clear. Human plasma derived from clinical trials is one of the most difficult sample sets to analyze using mass spectrometry-based proteomics due to the extensive sample preparation required and the need to process many samples to achieve statistical significance. Here, we describe an optimized and accessible device (Spin96) to accommodate up to 96 StageTips, a widely used sample preparation medium enabling efficient and consistent processing of samples prior to LC-MS/MS. We have applied this device to the analysis of human plasma from a clinical trial of IF. In this longitudinal study employing 8-weeks IF, we identified significant abundance differences induced by the IF intervention, including increased apolipoprotein A4 (APOA4) and decreased apolipoprotein C2 (APOC2) and C3 (APOC3). These changes correlated with a significant decrease in plasma triglycerides after the IF intervention. Given that these proteins have a role in regulating apolipoprotein particle metabolism, we propose that IF had a positive effect on lipid metabolism through modulation of HDL particle size and function. In addition, we applied a novel human protein variant database to detect common protein variants across the participants. We show that consistent detection of clinically relevant peptides derived from both alleles of many proteins is possible, including some that are associated with human metabolic phenotypes. Together, these findings illustrate the power of accessible workflows for proteomics analysis of clinical samples to yield significant biological insight.
Collapse
Affiliation(s)
- Dylan J Harney
- Charles Perkins Centre, School of Life and Environmental Sciences , University of Sydney , Sydney , NSW 2006 , Australia
| | - Amy T Hutchison
- Discipline of Medicine , University of Adelaide , Adelaide , SA 5005 , Australia
| | - Luke Hatchwell
- Charles Perkins Centre, School of Life and Environmental Sciences , University of Sydney , Sydney , NSW 2006 , Australia
| | - Sean J Humphrey
- Charles Perkins Centre, School of Life and Environmental Sciences , University of Sydney , Sydney , NSW 2006 , Australia
| | - David E James
- Charles Perkins Centre, School of Life and Environmental Sciences , University of Sydney , Sydney , NSW 2006 , Australia
| | - Samantha Hocking
- Central Clinical School, Faculty of Medicine and Health , University of Sydney , Sydney , NSW 2006 , Australia
| | - Leonie K Heilbronn
- Discipline of Medicine , University of Adelaide , Adelaide , SA 5005 , Australia
| | - Mark Larance
- Charles Perkins Centre, School of Life and Environmental Sciences , University of Sydney , Sydney , NSW 2006 , Australia
| |
Collapse
|
8
|
Hutchison AT, Liu B, Wood RE, Vincent AD, Thompson CH, O'Callaghan NJ, Wittert GA, Heilbronn LK. Effects of Intermittent Versus Continuous Energy Intakes on Insulin Sensitivity and Metabolic Risk in Women with Overweight. Obesity (Silver Spring) 2019; 27:50-58. [PMID: 30569640 DOI: 10.1002/oby.22345] [Citation(s) in RCA: 101] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 09/06/2018] [Accepted: 09/18/2018] [Indexed: 01/06/2023]
Abstract
OBJECTIVE This study aimed to compare intermittent fasting (IF) versus continuous energy intakes at 100% or 70% of calculated energy requirements on insulin sensitivity, cardiometabolic risk, body weight, and composition. METHODS Women with overweight (n = 88; 50 ± 1 years, BMI 32.3 ± 0.5 kg/m2 ) were randomized to one of four diets (IF70, IF100, dietary restriction [DR70], or control) in a 2:2:2:1 ratio for 8 weeks. IF groups fasted for 24 hours after breakfast on three nonconsecutive days per week. All foods were provided and diets matched for macronutrient composition (35% fat, 15% protein, 50% carbohydrate). Insulin sensitivity by hyperinsulinemic-euglycemic clamp, weight, body composition, and plasma markers were assessed following a "fed" day (12-hour fast) and a 24-hour fast (IF only). RESULTS IF70 displayed greater reductions in weight, fat mass, total- and low-density lipoprotein cholesterol, and nonesterified fatty acids compared with DR70 and IF100 (all P ≤ 0.05). IF100 lost more weight and fat than control. However, fasting insulin was increased. There were no group differences in insulin sensitivity by clamp; however, a 24-hour fast transiently reduced insulin sensitivity. CONCLUSIONS When prescribed at matched energy restriction, IF reduced weight and fat mass and improved total and low-density lipoprotein cholesterol more than DR. IF prescribed in energy balance did not improve health compared with other groups, despite modest weight loss.
Collapse
Affiliation(s)
- Amy T Hutchison
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Nutrition and Metabolism Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Bo Liu
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Nutrition and Metabolism Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Rachel E Wood
- School of Health Sciences, University of Tasmania, Launceston, Tasmania, Australia
| | - Andrew D Vincent
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | - Campbell H Thompson
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | - Nathan J O'Callaghan
- Nutrition and Metabolism Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
- Commonwealth Scientific and Industrial Research Organization (CSIRO) Food, Nutrition and Bioproducts Flagship, Adelaide, South Australia, Australia
| | - Gary A Wittert
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Nutrition and Metabolism Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Leonie K Heilbronn
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Nutrition and Metabolism Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| |
Collapse
|
9
|
Rico JE, Giesy SL, Haughey NJ, Boisclair YR, McFadden JW. Intravenous Triacylglycerol Infusion Promotes Ceramide Accumulation and Hepatic Steatosis in Dairy Cows. J Nutr 2018; 148:1529-1535. [PMID: 30281114 DOI: 10.1093/jn/nxy155] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 06/27/2018] [Indexed: 11/12/2022] Open
Abstract
Background Increased plasma free fatty acids (FFAs) impair insulin sensitivity in dairy cows via unknown mechanisms. In nonruminants, saturated FFAs upregulate the hepatic synthesis and secretion of ceramide, which inhibits insulin action. Objective We aimed to determine whether an increase in plasma FFAs promotes hepatic and plasma ceramide accumulation in dairy cows. Methods Six nonpregnant, nonlactating Holstein cows were used in a study with a crossover design and treatments consisting of intravenous infusion of either saline (control) or triacylglycerol emulsion (TG; 20 g/h) for 16 h. The feeding level was set at 120% of energy requirements. Blood was collected at regular intervals and liver was biopsied at 16 h. Ceramides, monohexosylceramides (Glc/Gal-Cer), lactosylceramides (LacCer), and sphingomyelins (SMs) in plasma and liver were profiled. Hepatic expression of ceramide synthases was determined. Data were analyzed with the use of mixed models, regressions, and Spearman rank correlations. Results After 16 h of infusion, plasma FFA concentrations were >5-fold and liver triacylglycerol concentrations were 4-fold greater in TG cows, relative to control. Plasma total and very long-chain ceramide (e.g., C24:0-ceramide) concentrations increased ∼4-fold in TG over control by hour 16 of infusion, while C16:0-ceramide were not modified by TG. Infusion of TG increased plasma Glc/Gal-Cer (e.g., C16:0-Glc/Gal-Cer, 4-fold by hour 16) relative to control, but did not alter LacCer or SM concentrations. Hepatic ceramide concentrations increased with TG relative to control (e.g., C24:0-ceramide by 1.7-fold). Hepatic expression of ceramide synthase 2 was 60% greater after TG infusion compared with the control. Circulating ceramides were related to circulating FFA and hepatic triacylglycerol concentrations (e.g., C24:0-ceramide, ρ = 0.73 and 0.80, respectively; P < 0.001). Conclusion Hepatic ceramide synthesis is associated with elevations in circulating FFAs and hepatic triacylglycerol during the induction of hyperlipidemia in dairy cows. This work supports the emerging evidence for the role of ceramide during hepatic steatosis and insulin antagonism in cows.
Collapse
Affiliation(s)
- J Eduardo Rico
- Department of Animal Science, Cornell University, Ithaca, NY.,Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV
| | - Sarah L Giesy
- Department of Animal Science, Cornell University, Ithaca, NY
| | - Norman J Haughey
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD
| | | | | |
Collapse
|
10
|
Makrecka-Kuka M, Sevostjanovs E, Vilks K, Volska K, Antone U, Kuka J, Makarova E, Pugovics O, Dambrova M, Liepinsh E. Plasma acylcarnitine concentrations reflect the acylcarnitine profile in cardiac tissues. Sci Rep 2017; 7:17528. [PMID: 29235526 PMCID: PMC5727517 DOI: 10.1038/s41598-017-17797-x] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 11/30/2017] [Indexed: 01/14/2023] Open
Abstract
Increased plasma concentrations of acylcarnitines (ACs) are suggested as a marker of metabolism disorders. The aim of the present study was to clarify which tissues are responsible for changes in the AC pool in plasma. The concentrations of medium- and long-chain ACs were changing during the fed-fast cycle in rat heart, muscles and liver. After 60 min running exercise, AC content was increased in fasted mice muscles, but not in plasma or heart. After glucose bolus administration in fasted rats, the AC concentrations in plasma decreased after 30 min but then began to increase, while in the muscles and liver, the contents of medium- and long-chain ACs were unchanged or even increased. Only the heart showed a decrease in medium- and long-chain AC contents that was similar to that observed in plasma. In isolated rat heart, but not isolated-contracting mice muscles, the significant efflux of medium- and long-chain ACs was observed. The efflux was reduced by 40% after the addition of glucose and insulin to the perfusion solution. Overall, these results indicate that during fed-fast cycle shifting the heart determines the medium- and long-chain AC profile in plasma, due to a rapid response to the availability of circulating energy substrates.
Collapse
Affiliation(s)
- Marina Makrecka-Kuka
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia.
| | - Eduards Sevostjanovs
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia
| | - Karlis Vilks
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia.,University of Latvia, Faculty of Biology, Jelgavas Str. 1, Riga, LV-1004, Latvia
| | - Kristine Volska
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia.,Riga Stradins University, Faculty of Pharmacy, Dzirciema Str. 16, Riga, LV-1007, Latvia
| | - Unigunde Antone
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia
| | - Janis Kuka
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia
| | - Elina Makarova
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia
| | - Osvalds Pugovics
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia
| | - Maija Dambrova
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia.,Riga Stradins University, Faculty of Pharmacy, Dzirciema Str. 16, Riga, LV-1007, Latvia
| | - Edgars Liepinsh
- Latvian Institute of Organic Synthesis, Aizkraukles Str. 21, Riga, LV-1006, Latvia
| |
Collapse
|
11
|
Clayton DJ, Burrell K, Mynott G, Creese M, Skidmore N, Stensel DJ, James LJ. Effect of 24-h severe energy restriction on appetite regulation and ad libitum energy intake in lean men and women. Am J Clin Nutr 2016; 104:1545-1553. [PMID: 27806971 DOI: 10.3945/ajcn.116.136937] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 10/03/2016] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Intermittent severe energy restriction (SER) can induce substantial weight loss, but the appetite regulatory responses to SER are unknown and may dictate long-term dietary adherence. OBJECTIVE We determined the effect of 24-h SER on appetite regulation, metabolism, and energy intake. DESIGN Eighteen lean men and women completed two 3-d trials in randomized, counterbalanced order. On day 1 subjects consumed standardized diets containing 100% (mean ± SD: 9.3 ± 1.3 MJ; energy balance) or 25% [2.3 ± 0.3 MJ; energy restriction (ER)] of energy requirements. On day 2, a standardized breakfast was consumed, with plasma concentrations of acylated ghrelin, glucagon-like peptide 1, insulin, glucose, and nonesterified fatty acids determined for 4 h. Ad libitum energy intake was assessed at lunch and dinner with subjective appetite and resting metabolism assessed throughout. On day 3, ad libitum energy intake was assessed at breakfast and by weighed food records. RESULTS Energy intake was 7% greater on day 2 (P < 0.05) during ER but not significantly different on day 3 (P = 0.557). Subjective appetite was greater during ER on the morning of day 2 (P < 0.05) but was not significantly different thereafter (P > 0.145). During ER, postprandial concentrations of acylated ghrelin were lower (P < 0.05), whereas glucose (P < 0.05) and nonesterified fatty acids (P < 0.0001) were higher. Postprandial glucagon-like peptide 17-36 (P = 0.784) and insulin (P = 0.06) concentrations were not significantly different between trials. Energy expenditure was lower during ER in the morning (P < 0.01). CONCLUSIONS In lean young adults, 24-h SER transiently elevated subjective appetite and marginally increased energy intake, but hormonal appetite markers did not respond in a manner indicative of hyperphagia. These results suggest that intermittent SER might be useful to attenuate energy intake and control body weight in this population. This trial was registered at www.clinicaltrials.gov.uk as NCT02696772.
Collapse
Affiliation(s)
- David J Clayton
- School of Sport, Exercise and Health Science, Loughborough University, Loughborough, United Kingdom
| | - Kirsty Burrell
- School of Sport, Exercise and Health Science, Loughborough University, Loughborough, United Kingdom
| | - Georgina Mynott
- School of Sport, Exercise and Health Science, Loughborough University, Loughborough, United Kingdom
| | - Mark Creese
- School of Sport, Exercise and Health Science, Loughborough University, Loughborough, United Kingdom
| | - Nicola Skidmore
- School of Sport, Exercise and Health Science, Loughborough University, Loughborough, United Kingdom
| | - David J Stensel
- School of Sport, Exercise and Health Science, Loughborough University, Loughborough, United Kingdom
| | - Lewis J James
- School of Sport, Exercise and Health Science, Loughborough University, Loughborough, United Kingdom
| |
Collapse
|
12
|
Clayton DJ, Creese M, Skidmore N, Stensel DJ, James LJ. No effect of 24 h severe energy restriction on appetite regulation and ad libitum energy intake in overweight and obese males. Int J Obes (Lond) 2016; 40:1662-1670. [PMID: 27339607 DOI: 10.1038/ijo.2016.106] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 04/14/2016] [Accepted: 05/02/2016] [Indexed: 01/22/2023]
Abstract
BACKGROUND/OBJECTIVES Long-term success of weight loss diets might depend on how the appetite regulatory system responds to energy restriction (ER). This study determined the effect of 24 h severe ER on subjective and hormonal appetite regulation, subsequent ad libitum energy intake and metabolism. SUBJECTS/METHODS In randomised order, eight overweight or obese males consumed a 24 h diet containing either 100% (12105 (1174 kJ; energy balance; EB) or 25% (3039 (295) kJ; ER) of estimated daily energy requirements (EER). An individualised standard breakfast containing 25% of EER (3216 (341) kJ) was consumed the following morning and resting energy expenditure, substrate utilisation and plasma concentrations of acylated ghrelin, glucagon-like peptide-1 (GLP-17-36), glucose-dependant insulinotropic peptide (GIP1-42), glucose, insulin and non-esterified fatty acid (NEFA) were determined for 4 h after breakfast. Ad libitum energy intake was assessed in the laboratory on day 2 and via food records on day 3. Subjective appetite was assessed throughout. RESULTS Energy intake was not different between trials for day 2 (EB: 14946 (1272) kJ; ER: 15251 (2114) kJ; P=0.623), day 3 (EB: 10580 (2457) kJ; 10812 (4357) kJ; P=0.832) or day 2 and 3 combined (P=0.693). Subjective appetite was increased during ER on day 1 (P<0.01), but was not different between trials on day 2 (P>0.381). Acylated ghrelin, GLP-17-36 and insulin were not different between trials (P>0.104). Post-breakfast area under the curve (AUC) for NEFA (P<0.05) and GIP1-42 (P<0.01) were greater during ER compared with EB. Fat oxidation was greater (P<0.01) and carbohydrate oxidation was lower (P<0.01) during ER, but energy expenditure was not different between trials (P=0.158). CONCLUSIONS These results suggest that 24 h severe ER does not affect appetite regulation or energy intake in the subsequent 48 h. This style of dieting may be conducive to maintenance of a negative EB by limiting compensatory eating behaviour, and therefore may assist with weight loss.
Collapse
Affiliation(s)
- D J Clayton
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, UK
| | - M Creese
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, UK
| | - N Skidmore
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, UK
| | - D J Stensel
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, UK
| | - L J James
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, UK
| |
Collapse
|
13
|
Ilan Y. Compounds of the sphingomyelin-ceramide-glycosphingolipid pathways as secondary messenger molecules: new targets for novel therapies for fatty liver disease and insulin resistance. Am J Physiol Gastrointest Liver Physiol 2016; 310:G1102-17. [PMID: 27173510 DOI: 10.1152/ajpgi.00095.2016] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 05/04/2016] [Indexed: 01/31/2023]
Abstract
The compounds of sphingomyelin-ceramide-glycosphingolipid pathways have been studied as potential secondary messenger molecules in various systems, along with liver function and insulin resistance. Secondary messenger molecules act directly or indirectly to affect cell organelles and intercellular interactions. Their potential role in the pathogenesis of steatohepatitis and diabetes has been suggested. Data samples collected from patients with Gaucher's disease, who had high levels of glucocerebroside, support a role for compounds from these pathways as a messenger molecules in the pathogenesis of fatty liver disease and diabetes. The present review summarizes some of the recent data on the role of glycosphingolipid molecules as messenger molecules in various physiological and pathological conditions, more specifically including insulin resistance and fatty liver disease.
Collapse
Affiliation(s)
- Yaron Ilan
- Gastroenterology and Liver Units, Department of Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| |
Collapse
|
14
|
Tinsley GM, La Bounty PM. Effects of intermittent fasting on body composition and clinical health markers in humans. Nutr Rev 2015; 73:661-74. [PMID: 26374764 DOI: 10.1093/nutrit/nuv041] [Citation(s) in RCA: 197] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Intermittent fasting is a broad term that encompasses a variety of programs that manipulate the timing of eating occasions by utilizing short-term fasts in order to improve body composition and overall health. This review examines studies conducted on intermittent fasting programs to determine if they are effective at improving body composition and clinical health markers associated with disease. Intermittent fasting protocols can be grouped into alternate-day fasting, whole-day fasting, and time-restricted feeding. Alternate-day fasting trials of 3 to 12 weeks in duration appear to be effective at reducing body weight (≈3%-7%), body fat (≈3-5.5 kg), total cholesterol (≈10%-21%), and triglycerides (≈14%-42%) in normal-weight, overweight, and obese humans. Whole-day fasting trials lasting 12 to 24 weeks also reduce body weight (≈3%-9%) and body fat, and favorably improve blood lipids (≈5%-20% reduction in total cholesterol and ≈17%-50% reduction in triglycerides). Research on time-restricted feeding is limited, and clear conclusions cannot be made at present. Future studies should examine long-term effects of intermittent fasting and the potential synergistic effects of combining intermittent fasting with exercise.
Collapse
Affiliation(s)
- Grant M Tinsley
- Correspondence: G.M. Tinsley is with the Department of Health, Human Performance, and Recreation, Baylor University, Waco, Texas, USA. P.M. LaBounty is with the Department of Exercise and Sport Science, University of Mary Hardin-Baylor, Belton, Texas, USA.
| | - Paul M La Bounty
- Correspondence: G.M. Tinsley is with the Department of Health, Human Performance, and Recreation, Baylor University, Waco, Texas, USA. P.M. LaBounty is with the Department of Exercise and Sport Science, University of Mary Hardin-Baylor, Belton, Texas, USA
| |
Collapse
|
15
|
Wijngaarden MA, Bakker LEH, van der Zon GC, 't Hoen PAC, van Dijk KW, Jazet IM, Pijl H, Guigas B. Regulation of skeletal muscle energy/nutrient-sensing pathways during metabolic adaptation to fasting in healthy humans. Am J Physiol Endocrinol Metab 2014; 307:E885-95. [PMID: 25249505 DOI: 10.1152/ajpendo.00215.2014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
During fasting, rapid metabolic adaptations are required to maintain energy homeostasis. This occurs by a coordinated regulation of energy/nutrient-sensing pathways leading to transcriptional activation and repression of specific sets of genes. The aim of the study was to investigate how short-term fasting affects whole body energy homeostasis and skeletal muscle energy/nutrient-sensing pathways and transcriptome in humans. For this purpose, 12 young healthy men were studied during a 24-h fast. Whole body glucose/lipid oxidation rates were determined by indirect calorimetry, and blood and skeletal muscle biopsies were collected and analyzed at baseline and after 10 and 24 h of fasting. As expected, fasting induced a time-dependent decrease in plasma insulin and leptin levels, whereas levels of ketone bodies and free fatty acids increased. This was associated with a metabolic shift from glucose toward lipid oxidation. At the molecular level, activation of the protein kinase B (PKB/Akt) and mammalian target of rapamycin pathways was time-dependently reduced in skeletal muscle during fasting, whereas the AMP-activated protein kinase activity remained unaffected. Furthermore, we report some changes in the phosphorylation and/or content of forkhead protein 1, sirtuin 1, and class IIa histone deacetylase 4, suggesting that these pathways might be involved in the transcriptional adaptation to fasting. Finally, transcriptome profiling identified genes that were significantly regulated by fasting in skeletal muscle at both early and late time points. Collectively, our study provides a comprehensive map of the main energy/nutrient-sensing pathways and transcriptomic changes during short-term adaptation to fasting in human skeletal muscle.
Collapse
Affiliation(s)
- Marjolein A Wijngaarden
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Leontine E H Bakker
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Gerard C van der Zon
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter A C 't Hoen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands; and
| | - Ko Willems van Dijk
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands; Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands; and
| | - Ingrid M Jazet
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Hanno Pijl
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Bruno Guigas
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands; Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
16
|
Frank P, Katz A, Andersson E, Sahlin K. Acute exercise reverses starvation-mediated insulin resistance in humans. Am J Physiol Endocrinol Metab 2013; 304:E436-43. [PMID: 23269410 DOI: 10.1152/ajpendo.00416.2012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Within 2-3 days of starvation, pronounced insulin resistance develops, possibly mediated by increased lipid load. Here, we show that one exercise bout increases mitochondrial fatty acid (FA) oxidation and reverses starvation-induced insulin resistance. Nine healthy subjects underwent 75-h starvation on two occasions: with no exercise (NE) or with one exercise session at the end of the starvation period (EX). Muscle biopsies were analyzed for mitochondrial function, contents of glycogen, and phosphorylation of regulatory proteins. Glucose tolerance and insulin sensitivity, measured with an intravenous glucose tolerance test (IVGTT), were impaired after starvation, but in EX the response was attenuated or abolished. Glycogen stores were reduced, and plasma FA was increased in both conditions, with a more pronounced effect in EX. After starvation, mitochondrial respiration decreased with complex I substrate (NE and EX), but in EX there was an increased respiration with complex I + II substrate. EX altered regulatory proteins associated with increases in glucose disposal (decreased phosphorylation of glycogen synthase), glucose transport (increased phosphorylation of Akt substrate of 160 kDa), and FA oxidation (increased phosphorylation of acetyl-CoA carboxylase). In conclusion, exercise reversed starvation-induced insulin resistance and was accompanied by reduced glycogen stores, increased lipid oxidation capacity, and activation of signaling proteins involved in glucose transport and FA metabolism.
Collapse
Affiliation(s)
- Per Frank
- The Swedish School of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Box 5626, 114 86 Stockholm, Sweden.
| | | | | | | |
Collapse
|
17
|
Soeters MR, Soeters PB, Schooneman MG, Houten SM, Romijn JA. Adaptive reciprocity of lipid and glucose metabolism in human short-term starvation. Am J Physiol Endocrinol Metab 2012; 303:E1397-407. [PMID: 23074240 DOI: 10.1152/ajpendo.00397.2012] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The human organism has tools to cope with metabolic challenges like starvation that are crucial for survival. Lipolysis, lipid oxidation, ketone body synthesis, tailored endogenous glucose production and uptake, and decreased glucose oxidation serve to protect against excessive erosion of protein mass, which is the predominant supplier of carbon chains for synthesis of newly formed glucose. The starvation response shows that the adaptation to energy deficit is very effective and coordinated with different adaptations in different organs. From an evolutionary perspective, this lipid-induced effect on glucose oxidation and uptake is very strong and may therefore help to understand why insulin resistance in obesity and type 2 diabetes mellitus is difficult to treat. The importance of reciprocity in lipid and glucose metabolism during human starvation should be taken into account when studying lipid and glucose metabolism in general and in pathophysiological conditions in particular.
Collapse
Affiliation(s)
- Maarten R Soeters
- Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | | | | | | | | |
Collapse
|
18
|
Soeters MR, Soeters PB. The evolutionary benefit of insulin resistance. Clin Nutr 2012; 31:1002-7. [PMID: 22682085 DOI: 10.1016/j.clnu.2012.05.011] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 04/26/2012] [Accepted: 05/16/2012] [Indexed: 12/13/2022]
Abstract
Insulin resistance is perceived as deleterious, associated with conditions as the metabolic syndrome, type 2 diabetes mellitus and critical illness. However, insulin resistance is evolutionarily well preserved and its persistence suggests that it benefits survival. Insulin resistance is important in various states such as starvation, immune activation, growth and cancer, to spare glucose for different biosynthetic purposes such as the production of NADPH, nucleotides in the pentose phosphate pathway and oxaloacetate for anaplerosis. In these conditions, total glucose oxidation by the tricarboxylic acid cycle is actually low and energy demands are largely met by fatty acid and ketone body oxidation. This beneficial role of insulin resistance has consequences for treatment and research. Insulin resistance should be investigated at the cellular, tissue and whole organism level. The metabolic pathways discussed here, should be integrated in the accepted and valid mechanistic events of insulin resistance before interfering with them to promote insulin sensitivity at any cost.
Collapse
Affiliation(s)
- Maarten R Soeters
- Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, PO Box 22660, 1100 DD Amsterdam, The Netherlands.
| | | |
Collapse
|
19
|
Vendelbo MH, Clasen BFF, Treebak JT, Møller L, Krusenstjerna-Hafstrøm T, Madsen M, Nielsen TS, Stødkilde-Jørgensen H, Pedersen SB, Jørgensen JOL, Goodyear LJ, Wojtaszewski JFP, Møller N, Jessen N. Insulin resistance after a 72-h fast is associated with impaired AS160 phosphorylation and accumulation of lipid and glycogen in human skeletal muscle. Am J Physiol Endocrinol Metab 2012; 302:E190-200. [PMID: 22028408 PMCID: PMC4971894 DOI: 10.1152/ajpendo.00207.2011] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
During fasting, human skeletal muscle depends on lipid oxidation for its energy substrate metabolism. This is associated with the development of insulin resistance and a subsequent reduction of insulin-stimulated glucose uptake. The underlying mechanisms controlling insulin action on skeletal muscle under these conditions are unresolved. In a randomized design, we investigated eight healthy subjects after a 72-h fast compared with a 10-h overnight fast. Insulin action on skeletal muscle was assessed by a hyperinsulinemic euglycemic clamp and by determining insulin signaling to glucose transport. In addition, substrate oxidation, skeletal muscle lipid content, regulation of glycogen synthesis, and AMPK signaling were assessed. Skeletal muscle insulin sensitivity was reduced profoundly in response to a 72-h fast and substrate oxidation shifted to predominantly lipid oxidation. This was associated with accumulation of both lipid and glycogen in skeletal muscle. Intracellular insulin signaling to glucose transport was impaired by regulation of phosphorylation at specific sites on AS160 but not TBC1D1, both key regulators of glucose uptake. In contrast, fasting did not impact phosphorylation of AMPK or insulin regulation of Akt, both of which are established upstream kinases of AS160. These findings show that insulin resistance in muscles from healthy individuals is associated with suppression of site-specific phosphorylation of AS160, without Akt or AMPK being affected. This impairment of AS160 phosphorylation, in combination with glycogen accumulation and increased intramuscular lipid content, may provide the underlying mechanisms for resistance to insulin in skeletal muscle after a prolonged fast.
Collapse
Affiliation(s)
| | - B. F. F. Clasen
- Departments of 1Internal Medicine and Endocrinology and
- 2Clinical Pharmacology, Aarhus University Hospital, Aarhus;
| | - J. T. Treebak
- 3Molecular Physiology Group, Department of Exercise and Sport Sciences, University of Copenhagen, Copenhagen;
| | - L. Møller
- Departments of 1Internal Medicine and Endocrinology and
| | | | - M. Madsen
- Departments of 1Internal Medicine and Endocrinology and
| | - T. S. Nielsen
- Departments of 1Internal Medicine and Endocrinology and
- 2Clinical Pharmacology, Aarhus University Hospital, Aarhus;
| | | | | | | | - L. J. Goodyear
- 5Joslin Diabetes Center and Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - J. F. P. Wojtaszewski
- 3Molecular Physiology Group, Department of Exercise and Sport Sciences, University of Copenhagen, Copenhagen;
| | - N. Møller
- Departments of 1Internal Medicine and Endocrinology and
| | - N. Jessen
- Departments of 1Internal Medicine and Endocrinology and
- 2Clinical Pharmacology, Aarhus University Hospital, Aarhus;
| |
Collapse
|
20
|
Soeters MR, Huidekoper HH, Duran M, Ackermans MT, Endert E, Fliers E, Wijburg FA, Wanders RJ, Sauerwein HP, Serlie MJ. Extended metabolic evaluation of suspected symptomatic hypoglycemia: the prolonged fast and beyond. Metabolism 2010; 59:1543-50. [PMID: 20189609 DOI: 10.1016/j.metabol.2010.01.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Revised: 01/11/2010] [Accepted: 01/27/2010] [Indexed: 11/21/2022]
Abstract
The diagnostic evaluation of spontaneous hypoglycemia in adults is mainly directed at detecting an insulinoma. Its interpretation is troublesome in those patients who develop low venous plasma glucose levels with appropriate hypoinsulinemia during a prolonged supervised fast. In this study, we investigated in this group of patients whether abnormalities in intermediary metabolism (fatty acid oxidation and amino/organic acids) could be detected that might explain the hypoinsulinemic hypoglycemia. Ten patients with otherwise unexplained low venous plasma glucose levels (<3 mmol/L) during prolonged fasting were included in the study. The patients participated in an extended metabolic protocol based on stable isotope techniques after an overnight fast to explore abnormalities in endogenous glucose production and intermediary metabolism. Endogenous glucose production, glucoregulatory hormones, plasma acylcarnitines, gluconeogenic amino acids, and rates of fatty acid and carbohydrate oxidation after 16 and 22 hours of fasting were measured. Although during the prolonged fast all patients had low venous plasma glucose level, there were no hypoglycemic events during the extended metabolic protocol. No abnormalities in endogenous glucose production (compared with reference values obtained in young healthy volunteers), fatty acid oxidation, or amino acid/organic acids were found in this patient group. In a group of patients exhibiting low venous plasma glucose levels during prolonged fasting in whom insulinoma was excluded, we found no signs of metabolic disorders. Therefore, the observation of low plasma glucose values in this subgroup of patients probably does not warrant extensive metabolic evaluation.
Collapse
Affiliation(s)
- Maarten R Soeters
- Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Hoeks J, van Herpen NA, Mensink M, Moonen-Kornips E, van Beurden D, Hesselink MKC, Schrauwen P. Prolonged fasting identifies skeletal muscle mitochondrial dysfunction as consequence rather than cause of human insulin resistance. Diabetes 2010; 59:2117-25. [PMID: 20573749 PMCID: PMC2927932 DOI: 10.2337/db10-0519] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Type 2 diabetes and insulin resistance have been associated with mitochondrial dysfunction, but it is debated whether this is a primary factor in the pathogenesis of the disease. To test the concept that mitochondrial dysfunction is secondary to the development of insulin resistance, we employed the unique model of prolonged fasting in humans. Prolonged fasting is a physiologic condition in which muscular insulin resistance develops in the presence of increased free fatty acid (FFA) levels, increased fat oxidation and low glucose and insulin levels. It is therefore anticipated that skeletal muscle mitochondrial function is maintained to accommodate increased fat oxidation unless factors secondary to insulin resistance exert negative effects on mitochondrial function. RESEARCH DESIGN AND METHODS While in a respiration chamber, twelve healthy males were subjected to a 60 h fast and a 60 h normal fed condition in a randomized crossover design. Afterward, insulin sensitivity was assessed using a hyperinsulinemic-euglycemic clamp, and mitochondrial function was quantified ex vivo in permeabilized muscle fibers using high-resolution respirometry. RESULTS Indeed, FFA levels were increased approximately ninefold after 60 h of fasting in healthy male subjects, leading to elevated intramuscular lipid levels and decreased muscular insulin sensitivity. Despite an increase in whole-body fat oxidation, we observed an overall reduction in both coupled state 3 respiration and maximally uncoupled respiration in permeabilized skeletal muscle fibers, which could not be explained by changes in mitochondrial density. CONCLUSIONS These findings confirm that the insulin-resistant state has secondary negative effects on mitochondrial function. Given the low insulin and glucose levels after prolonged fasting, hyperglycemia and insulin action per se can be excluded as underlying mechanisms, pointing toward elevated plasma FFA and/or intramuscular fat accumulation as possible causes for the observed reduction in mitochondrial capacity.
Collapse
Affiliation(s)
- Joris Hoeks
- Department of Human Biology, School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre, Maastricht, the Netherlands.
| | | | | | | | | | | | | |
Collapse
|
22
|
Wang ZG, Wang Q, Wang WJ, Qin HL. Randomized clinical trial to compare the effects of preoperative oral carbohydrate versus placebo on insulin resistance after colorectal surgery. Br J Surg 2010; 97:317-27. [PMID: 20101593 DOI: 10.1002/bjs.6963] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Abstract
Background
Preoperative oral carbohydrate (OCH) reduces postoperative insulin resistance (PIR). This randomized trial investigated whether this effect is related to insulin-induced activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB) signalling pathway.
Methods
Patients with colorectal cancer scheduled for elective open resection were randomly assigned to preoperative OCH, fasting or placebo. Preoperative general well-being, insulin resistance before and immediately after surgery, and postoperative expression of PI3K, PKB, protein tyrosine kinase (PTK) and glucose transporter 4 (GLUT4) in rectus abdominis muscle were evaluated.
Results
Patient and operative characteristics did not differ between groups. Subjective well-being was significantly better in OCH and placebo groups than in the fasting group, primarily because of reduced thirst (P = 0·005) and hunger (P = 0·041). PIR was significantly greater in fasting and placebo groups (P < 0·010). By the end of surgery, muscle PTK activity as well as PI3K and PKB levels were significantly increased in the OCH group compared with values in fasting and placebo groups (P < 0·050), but GLUT4 expression was unaffected.
Conclusion
PIR involves the PI3K/PKB signalling pathway. Preoperative OCH intake improves preoperative subjective feelings of hunger and thirst compared with fasting, while attenuating PIR by stimulation of the PI3K/PKB pathway. Registration number: NCT00755729 (http://www.clinicaltrials.gov).
Collapse
Affiliation(s)
- Z G Wang
- Department of General Surgery, Shanghai Chang Zheng Hospital, Second Military Medical University, Shanghai, China
| | - Q Wang
- Department of General Surgery, Shanghai Chang Zheng Hospital, Second Military Medical University, Shanghai, China
| | - W J Wang
- Department of General Surgery, Shanghai Chang Zheng Hospital, Second Military Medical University, Shanghai, China
| | - H L Qin
- Department of General Surgery, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
23
|
Soeters MR, Lammers NM, Dubbelhuis PF, Ackermans M, Jonkers-Schuitema CF, Fliers E, Sauerwein HP, Aerts JM, Serlie MJ. Intermittent fasting does not affect whole-body glucose, lipid, or protein metabolism. Am J Clin Nutr 2009; 90:1244-51. [PMID: 19776143 DOI: 10.3945/ajcn.2008.27327] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Intermittent fasting (IF) was shown to increase whole-body insulin sensitivity, but it is uncertain whether IF selectively influences intermediary metabolism. Such selectivity might be advantageous when adapting to periods of food abundance and food shortage. OBJECTIVE The objective was to assess effects of IF on intermediary metabolism and energy expenditure. DESIGN Glucose, glycerol, and valine fluxes were measured after 2 wk of IF and a standard diet (SD) in 8 lean healthy volunteers in a crossover design, in the basal state and during a 2-step hyperinsulinemic euglycemic clamp, with assessment of energy expenditure and phosphorylation of muscle protein kinase B (AKT), glycogen synthase kinase (GSK), and mammalian target of rapamycine (mTOR). We hypothesized that IF selectively increases peripheral glucose uptake and lowers proteolysis, thereby protecting protein stores. RESULTS No differences in body weight were observed between the IF and SD groups. Peripheral glucose uptake and hepatic insulin sensitivity during the clamp did not significantly differ between the IF and SD groups. Likewise, lipolysis and proteolysis were not different between the IF and SD groups. IF decreased resting energy expenditure. IF had no effect on the phosphorylation of AKT but significantly increased the phosphorylation of glycogen synthase kinase. Phosphorylation of mTOR was significantly lower after IF than after the SD. CONCLUSIONS IF does not affect whole-body glucose, lipid, or protein metabolism in healthy lean men despite changes in muscle phosphorylation of GSK and mTOR. The decrease in resting energy expenditure after IF indicates the possibility of an increase in weight during IF when caloric intake is not adjusted. This study was registered at www.trialregister.nl as NTR1841.
Collapse
Affiliation(s)
- Maarten R Soeters
- Department of Endocrinology and Metabolism, University of Amsterdam, Amsterdam, Netherlands.
| | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Visser WE, Heemstra KA, Swagemakers SMA, Ozgür Z, Corssmit EP, Burggraaf J, van Ijcken WFJ, van der Spek PJ, Smit JWA, Visser TJ. Physiological thyroid hormone levels regulate numerous skeletal muscle transcripts. J Clin Endocrinol Metab 2009; 94:3487-96. [PMID: 19567520 DOI: 10.1210/jc.2009-0782] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
CONTEXT Skeletal muscle is an important target tissue for thyroid hormone (TH). It is currently unknown which genes are regulated by physiological TH levels. OBJECTIVE We examined the effects of l-thyroxine on human skeletal muscle transcriptome. DESIGN Microarray analysis of transcript levels was performed using skeletal muscle biopsies from patients under euthyroid and hypothyroid conditions. SETTING The study was conducted in a university hospital laboratory. PATIENTS We studied skeletal muscle obtained from 10 thyroidectomized patients with differentiated thyroid carcinoma on and after 4 wk off L-thyroxine replacement. MEAN OUTCOME MEASURES Gene expression changes were measured using microarrays. Results were analyzed using dedicated statistical methods. RESULTS We detected 607 differentially expressed genes on L-thyroxine treatment, of which approximately 60% were positively and approximately 40% were negatively regulated. Representative genes were validated by quantitative PCR. Genes involved in energy and fuel metabolism were overrepresented among the up-regulated genes, of which a large number were newly associated with thyroid state. L-thyroxine therapy induced a large down-regulation of the primary transcripts of the noncoding microRNA pair miR-206/miR-133b. CONCLUSION We demonstrated that physiological levels of TH regulate a myriad of genes in human skeletal muscle. The identification of novel putatively TH-responsive genes may provide the molecular basis of clinical effects in subjects with different TH status. The observation that TH regulates microRNAs reveals a new layer of complexity by which TH influences cellular processes.
Collapse
Affiliation(s)
- W Edward Visser
- Erasmus University Medical Center, Department of Internal Medicine, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Zijlmans WCWR, van Kempen AAMW, Serlie MJ, Sauerwein HP. Glucose metabolism in children: influence of age, fasting, and infectious diseases. Metabolism 2009; 58:1356-65. [PMID: 19501855 DOI: 10.1016/j.metabol.2009.04.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2009] [Revised: 04/22/2009] [Accepted: 04/28/2009] [Indexed: 10/20/2022]
Abstract
This review describes the occurrence of hypoglycemia in young children as a common and serious complication that needs to be avoided because of the high risk of brain damage and mortality. Young age, fasting, and severe infectious disease are considered important risk factors. The limited data on the effect of these risk factors on glucose metabolism in children are discussed and compared with data on glucose metabolism in adults. The observations discussed may have implications for further research on glucose kinetics in young children with infectious disease.
Collapse
Affiliation(s)
- Wilco C W R Zijlmans
- Department of Pediatrics, Diakonessen Hospital, PO Box 1814, Paramaribo, Suriname (SA).
| | | | | | | |
Collapse
|
26
|
Heemstra KA, Soeters MR, Fliers E, Serlie MJ, Burggraaf J, van Doorn MB, van der Klaauw AA, Romijn JA, Smit JW, Corssmit EP, Visser TJ. Type 2 iodothyronine deiodinase in skeletal muscle: effects of hypothyroidism and fasting. J Clin Endocrinol Metab 2009; 94:2144-50. [PMID: 19293265 DOI: 10.1210/jc.2008-2520] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
CONTEXT The iodothyronine deiodinases D1, D2, and D3 enable tissue-specific adaptation of thyroid hormone levels in response to various conditions, such as hypothyroidism or fasting. The possible expression of D2 mRNA in skeletal muscle is intriguing because this enzyme could play a role in systemic as well as local T3 production. OBJECTIVE We determined D2 activity and D2 mRNA expression in human skeletal muscle biopsies under control conditions and during hypothyroidism, fasting, and hyperinsulinemia. DESIGN This was a prospective study. SETTING The study was conducted at a university hospital. PATIENTS We studied 11 thyroidectomized patients with differentiated thyroid carcinoma (DTC) on and after 4 wk off T4( replacement and six healthy lean subjects in the fasting state and during hyperinsulinemia after both 14 and 62 h of fasting. MEAN OUTCOME MEASURES D2 activity and D2 mRNA levels were measured in skeletal muscle samples. RESULTS No differences were observed in muscle D2 mRNA levels in DTC patients on and off T4 replacement therapy. In healthy subjects, muscle D2 mRNA levels were lower after 62 h compared to 14 h of fasting. Insulin increased mRNA expression after 62 h, but not after 14 h of fasting. Skeletal muscle D2 activities were very low and not influenced by hypothyroidism and fasting. CONCLUSION Human skeletal muscle D2 mRNA expression is modulated by fasting and insulin, but not by hypothyroidism. The lack of a clear effect of D2 mRNA modulation on the observed low D2 activities questions the physiological relevance of D2 activity in human skeletal muscle.
Collapse
Affiliation(s)
- Karen A Heemstra
- Leiden University Medical Centre, Department of Endocrinology and Metabolic Diseases, P.O. Box 9600, Leiden 2300 RC, The Netherlands.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
The transition from the fed to the fasted resting state is characterized by, among other things, changes in lipid metabolism and peripheral insulin resistance. Acylcarnitines have been suggested to play a role in insulin resistance, as well as other long-chain fatty acid metabolites. Plasma levels of long-chain acylcarnitines increase during fasting, but this is unknown for muscle long-chain acylcarnitines. In the present study we investigated whether muscle long-chain acylcarnitines increase during fasting and we investigated their relationship with glucose/fat oxidation and insulin sensitivity in lean healthy humans. After 14 h and 62 h of fasting, glucose fluxes, substrate oxidation, and plasma and muscle acylcarnitines were measured before and during a hyperinsulinaemic–euglycaemic clamp. Hyperinsulinaemia decreased long-chain muscle acylcarnitines after 14 h of fasting, but not after 62 h of fasting. In both the basal state and during the clamp, glucose oxidation was lower and fatty acid oxidation was higher after 62 h compared with 14 h of fasting. Absolute changes in glucose and fatty acid oxidation in the basal compared with hyperinsulinaemic state were not different. Muscle long-chain acylcarnitines did not correlate with glucose oxidation, fatty acid oxidation or insulin-mediated peripheral glucose uptake. After 62 h of fasting, the suppression of muscle long-chain acylcarnitines by insulin was attenuated compared with 14 h of fasting. Muscle long-chain acylcarnitines do not unconditionally reflect fatty acid oxidation. The higher fatty acid oxidation during hyperinsulinaemia after 62 h compared with 14 h of fasting, although the absolute decrease in fatty acid oxidation was not different, suggests a different set point.
Collapse
|
28
|
Straczkowski M, Kowalska I. The role of skeletal muscle sphingolipids in the development of insulin resistance. Rev Diabet Stud 2008; 5:13-24. [PMID: 18548166 DOI: 10.1900/rds.2008.5.13] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Insulin resistance is an important risk factor for type 2 diabetes, obesity, cardiovascular disease, polycystic ovary syndrome and other diseases. The most important stage in the development of insulin resistance is impairment of insulin-stimulated skeletal muscle glucose uptake. There is evidence that intramyocellular lipids might be responsible for this process through inhibition of insulin signaling. One of the important intracellular lipid pools is associated with the sphingomyelin signaling pathway. The second messenger in this pathway is ceramide. In vitro data indicate that ceramide inhibits insulin signaling, mainly through inactivation of protein kinase B. In vivo data suggest that ceramide accumulation within muscle cells might be associated with the development of insulin resistance. In this review, we discuss both in vitro and in vivo evidence for the role of muscle ceramide in the impairment of insulin action with particular focus on the question whether findings from animal studies are applicable to humans. We describe problems that are unresolved so far and topics of potential interest for future research.
Collapse
Affiliation(s)
- Marek Straczkowski
- Department of Endocrinology, Diabetology and Internal Medicine, Medical University of Bialystok, Poland
| | | |
Collapse
|