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van der Heijden I, West S, Monteyne AJ, Finnigan TJA, Abdelrahman DR, Murton AJ, Stephens FB, Wall BT. Algae Ingestion Increases Resting and Exercised Myofibrillar Protein Synthesis Rates to a Similar Extent as Mycoprotein in Young Adults. J Nutr 2023; 153:3406-3417. [PMID: 37716611 PMCID: PMC10739781 DOI: 10.1016/j.tjnut.2023.08.035] [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: 07/11/2023] [Revised: 08/23/2023] [Accepted: 08/31/2023] [Indexed: 09/18/2023] Open
Abstract
BACKGROUND Spirulina [SPIR] (cyanobacterium) and chlorella [CHLO] (microalgae) are foods rich in protein and essential amino acids; however, their capacity to stimulate myofibrillar protein synthesis (MyoPS) in humans remains unknown. OBJECTIVES We assessed the impact of ingesting SPIR and CHLO compared with an established high-quality nonanimal-derived dietary protein source (fungal-derived mycoprotein [MYCO]) on plasma amino acid concentrations, as well as resting and postexercise MyoPS rates in young adults. METHODS Thirty-six healthy young adults (age: 22 ± 3 y; BMI: 23 ± 3 kg·m-2; male [m]/female [f], 18/18) participated in a randomized, double-blind, parallel-group trial. Participants received a primed, continuous infusion of L-[ring-2H5]-phenylalanine and completed a bout of unilateral-resistance leg exercise before ingesting a drink containing 25 g protein from MYCO (n = 12; m/f, 6/6), SPIR (n = 12; m/f, 6/6), or CHLO (n = 12; m/f, 6/6). Blood and bilateral muscle samples were collected at baseline and during a 4-h postprandial and postexercise period to assess the plasma amino acid concentrations and MyoPS rates in rested and exercised tissue. RESULTS Protein ingestion increased the plasma total and essential amino acid concentrations (time effects; all P < 0.001), but most rapidly and with higher peak responses following the ingestion of SPIR compared with MYCO and CHLO (P < 0.05), and MYCO compared with CHLO (P < 0.05). Protein ingestion increased MyoPS rates (time effect; P < 0.001) in both rested (MYCO, from 0.041 ± 0.032 to 0.060 ± 0.015%·h-1; SPIR, from 0.042 ± 0.030 to 0.066 ± 0.022%·h-1; and CHLO, from 0.037 ± 0.007 to 0.055 ± 0.019%·h-1, respectively) and exercised tissue (MYCO, from 0.046 ± 0.014 to 0.092 ± 0.024%·h-1; SPIR, from 0.038 ± 0.011 to 0.086 ± 0.028%·h-1; and CHLO, from 0.048 ± 0.019 to 0.090 ± 0.024%·h-1, respectively), with no differences between groups (interaction effect; P > 0.05), but with higher rates in exercised compared with rested muscle (time × exercise effect; P < 0.001). CONCLUSIONS The ingestion of a single bolus of algae-derived SPIR and CHLO increases resting and postexercise MyoPS rates to a comparable extent as MYCO, despite divergent postprandial plasma amino acid responses.
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Affiliation(s)
- Ino van der Heijden
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Sam West
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Alistair J Monteyne
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | | | - Doaa R Abdelrahman
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, United States; Sealy Center on Aging, University of Texas Medical Branch, Galveston, TX, United States
| | - Andrew J Murton
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, United States; Sealy Center on Aging, University of Texas Medical Branch, Galveston, TX, United States
| | - Francis B Stephens
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Benjamin T Wall
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom.
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West S, Monteyne AJ, Whelehan G, van der Heijden I, Abdelrahman DR, Murton AJ, Finnigan TJA, Stephens FB, Wall BT. Ingestion of mycoprotein, pea protein, and their blend support comparable postexercise myofibrillar protein synthesis rates in resistance-trained individuals. Am J Physiol Endocrinol Metab 2023; 325:E267-E279. [PMID: 37529834 PMCID: PMC10655824 DOI: 10.1152/ajpendo.00166.2023] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 08/03/2023]
Abstract
Pea protein is an attractive nonanimal-derived protein source to support dietary protein requirements. However, although high in leucine, a low methionine content has been suggested to limit its anabolic potential. Mycoprotein has a complete amino acid profile which, at least in part, may explain its ability to robustly stimulate myofibrillar protein synthesis (MyoPS) rates. We hypothesized that an inferior postexercise MyoPS response would be seen following ingestion of pea protein compared with mycoprotein, which would be (partially) rescued by blending the two sources. Thirty-three healthy, young [age: 21 ± 1 yr, body mass index (BMI): 24 ± 1 kg·m-2] and resistance-trained participants received primed, continuous infusions of l-[ring-2H5]phenylalanine and completed a bout of whole body resistance exercise before ingesting 25 g of protein from mycoprotein (MYC, n = 11), pea protein (PEA, n = 11), or a blend (39% MYC, 61% PEA) of the two (BLEND, n = 11). Blood and muscle samples were taken pre-, 2 h, and 4 h postexercise/protein ingestion to assess postabsorptive and postprandial postexercise myofibrillar protein fractional synthetic rates (FSRs). Protein ingestion increased plasma essential amino acid and leucine concentrations (time effect; P < 0.0001), but more rapidly in BLEND and PEA compared with MYC (time × condition interaction; P < 0.0001). From similar postabsorptive values (MYC, 0.026 ± 0.008%·h-1; PEA, 0.028 ± 0.007%·h-1; BLEND, 0.026 ± 0.006%·h-1), resistance exercise and protein ingestion increased myofibrillar FSRs (time effect; P < 0.0001) over a 4-h postprandial period (MYC, 0.076 ± 0.004%·h-1; PEA, 0.087 ± 0.01%·h-1; BLEND, 0.085 ± 0.01%·h-1), with no differences between groups (all; P > 0.05). These data show that all three nonanimal-derived protein sources have utility in supporting postexercise muscle reconditioning.NEW & NOTEWORTHY This study provides evidence that pea protein (PEA), mycoprotein (MYC), and their blend (BLEND) can support postexercise myofibrillar protein synthesis rates following a bout of whole body resistance exercise. Furthermore, these data suggest that a methionine deficiency in pea may not limit its capacity to stimulate an acute increase in muscle protein synthesis (MPS).
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Affiliation(s)
- Sam West
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Alistair J Monteyne
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Gráinne Whelehan
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Ino van der Heijden
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Doaa R Abdelrahman
- Department of Surgery, University of Texas Medical Branch, Galveston, Texas, United States
- Sealy Center of Aging, University of Texas Medical Branch, Galveston, Texas, United States
| | - Andrew J Murton
- Department of Surgery, University of Texas Medical Branch, Galveston, Texas, United States
- Sealy Center of Aging, University of Texas Medical Branch, Galveston, Texas, United States
| | | | - Francis B Stephens
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Benjamin T Wall
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
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Gries KJ, Hart CR, Kunz HE, Ryan Z, Zhang X, Parvizi M, Liu Y, Dasari S, Lanza I. Acute responsiveness to single leg cycling in adults with obesity. Physiol Rep 2022; 10:e15539. [PMID: 36541258 PMCID: PMC9768637 DOI: 10.14814/phy2.15539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 10/11/2022] [Accepted: 11/26/2022] [Indexed: 05/28/2023] Open
Abstract
Obesity is associated with several skeletal muscle impairments which can be improved through an aerobic exercise prescription. The possibility that exercise responsiveness is diminished in people with obesity has been suggested but not well-studied. The purpose of this study was to investigate how obesity influences acute exercise responsiveness in skeletal muscle and circulating amino metabolites. Non-obese (NO; n = 19; 10F/9M; BMI = 25.1 ± 2.8 kg/m2 ) and Obese (O; n = 21; 14F/7M; BMI = 37.3 ± 4.6 kg/m2 ) adults performed 30 min of single-leg cycling at 70% of VO2 peak. 13 C6 -Phenylalanine was administered intravenously for muscle protein synthesis measurements. Serial muscle biopsies (vastus lateralis) were collected before exercise and 3.5- and 6.5-h post-exercise to measure protein synthesis and gene expression. Targeted plasma metabolomics was used to quantitate amino metabolites before and 30 and 90 min after exercise. The exercise-induced fold change in mixed muscle protein synthesis trended (p = 0.058) higher in NO (1.28 ± 0.54-fold) compared to O (0.95 ± 0.42-fold) and was inversely related to BMI (R2 = 0.140, p = 0.027). RNA sequencing revealed 331 and 280 genes that were differentially expressed after exercise in NO and O, respectively. Gene set enrichment analysis showed O had six blunted pathways related to metabolism, cell to cell communication, and protein turnover after exercise. The circulating amine response further highlighted dysregulations related to protein synthesis and metabolism in adults with obesity at the basal state and in response to the exercise bout. Collectively, these data highlight several unique pathways in individuals with obesity that resulted in a modestly blunted exercise response.
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Affiliation(s)
- Kevin J. Gries
- Endocrine Research Unit, Division of EndocrinologyDepartment of Internal Medicine, Mayo ClinicRochesterMinnesotaUSA
- Department of Physical Therapy, School of Health ProfessionsConcordia University of WisconsinMequonWisconsinUSA
| | - Corey R. Hart
- Endocrine Research Unit, Division of EndocrinologyDepartment of Internal Medicine, Mayo ClinicRochesterMinnesotaUSA
- Air Force Research Laboratory, 711th Human Performance Wing, Wright Patterson Air Force BaseDaytonOhioUSA
| | - Hawley E. Kunz
- Endocrine Research Unit, Division of EndocrinologyDepartment of Internal Medicine, Mayo ClinicRochesterMinnesotaUSA
| | - Zachary Ryan
- Endocrine Research Unit, Division of EndocrinologyDepartment of Internal Medicine, Mayo ClinicRochesterMinnesotaUSA
| | - Xiaoyan Zhang
- Endocrine Research Unit, Division of EndocrinologyDepartment of Internal Medicine, Mayo ClinicRochesterMinnesotaUSA
- Department of GeriatricsShanghai Jiaotong University Affiliated Sixth People's HospitalShanghaiChina
| | - Mojtaba Parvizi
- Endocrine Research Unit, Division of EndocrinologyDepartment of Internal Medicine, Mayo ClinicRochesterMinnesotaUSA
| | - Yuanhang Liu
- Department of Biomedical Statistics and Informatics, Mayo ClinicRochesterMinnesotaUSA
| | - Surendra Dasari
- Department of Biomedical Statistics and Informatics, Mayo ClinicRochesterMinnesotaUSA
| | - Ian R. Lanza
- Endocrine Research Unit, Division of EndocrinologyDepartment of Internal Medicine, Mayo ClinicRochesterMinnesotaUSA
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Kunz HE, Michie KL, Gries KJ, Zhang X, Ryan ZC, Lanza IR. A Randomized Trial of the Effects of Dietary n3-PUFAs on Skeletal Muscle Function and Acute Exercise Response in Healthy Older Adults. Nutrients 2022; 14:nu14173537. [PMID: 36079794 PMCID: PMC9459748 DOI: 10.3390/nu14173537] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 12/16/2022] Open
Abstract
Skeletal muscle is critical for maintaining mobility, independence, and metabolic health in older adults. However, a common feature of aging is the progressive loss of skeletal muscle mass and function, which is often accompanied by mitochondrial impairments, oxidative stress, and insulin resistance. Exercise improves muscle strength, mitochondrial health, and cardiorespiratory fitness, but older adults often exhibit attenuated anabolic responses to acute exercise. Chronic inflammation associated with aging may contribute to this "anabolic resistance" and therapeutic interventions that target inflammation may improve exercise responsiveness. To this end, we conducted a randomized controlled trial to determine the effect of 6 months of dietary omega-3 polyunsaturated fatty acids (n3-PUFA) supplementation on skeletal muscle function (mass, strength), mitochondrial physiology (respiration, ATP production, ROS generation), and acute exercise responsiveness at the level of the muscle (fractional synthesis rate) and the whole-body (amino acid kinetics) in healthy older adults. When compared with a corn oil placebo (n = 33; 71.5 ± 4.8 years), older adults treated with 4 g/day n3-PUFA (n = 30; 71.4 ± 4.5 years) exhibited modest but significant increases in muscle strength (3.1 ± 14.7% increase in placebo vs. 7.5 ± 14.1% increase in n3-PUFA; p = 0.039). These improvements in muscle strength with n3-PUFA supplementation occurred in the absence of any effects on mitochondrial function and a minor attenuation of the acute response to exercise compared to placebo. Together, these data suggest modest benefits of dietary n3-PUFAs to muscle function in healthy older adults. Future studies may elucidate whether n3-PUFA supplementation improves the exercise response in elderly individuals with co-morbidities, such as chronic inflammatory disease or sarcopenia.
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Affiliation(s)
- Hawley E. Kunz
- Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Kelly L. Michie
- Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Kevin J. Gries
- Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Department of Physical Therapy, School of Health Professions, Concordia University of Wisconsin, Mequon, WI 53097, USA
| | - Xiaoyan Zhang
- Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Department of Geriatrics, Shanghai Jiaotong University Affiliated Sixth People’s Hospital, Shanghai 200233, China
| | - Zachary C. Ryan
- Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Ian R. Lanza
- Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Correspondence:
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Moore DR, Williamson EP, Hodson N, Estafanos S, Mazzulla M, Kumbhare D, Gillen JB. Walking or body weight squat 'activity snacks' increase dietary amino acid utilization for myofibrillar protein synthesis during prolonged sitting. J Appl Physiol (1985) 2022; 133:777-785. [PMID: 35952344 DOI: 10.1152/japplphysiol.00106.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Interrupting prolonged sitting with intermittent exercise enhances postprandial glycemic control but has unknown effects on sensitizing skeletal muscle to dietary amino acids. We hypothesized that brief walking or body weight squats would enhance the utilization of dietary phenylalanine for myofibrillar protein synthesis (MyoPS) during prolonged sitting. Participants (7 males and 5 females; ~23y; ~25.1kg/m2; ~7300 steps/d) completed three 7.5h trials consisting of prolonged sitting (SIT) or sitting with intermittent (every 30 minutes) walking (WALK) or body weight squatting (SQUAT). Two mixed-macronutrient meals (~55:30:15% carbohydrate:fat:protein), enriched with L-[ring-2H5]phenylalanine or L-[ring-13C6]phenylalanine, were provided to mimic breakfast and lunch. Tracer incorporation into myofibrillar protein was determined from the vastus lateralis with MyoPS estimated using plasma enrichment as precursor surrogate. Phosphorylation of candidate anabolic signaling proteins were determined by immunoblotting. There was no difference between conditions (p≥0.78) in the time course or area under the curve for plasma phenylalanine enrichment. MyoPS was greater (p<0.05, weighted planned comparison) in SQUAT (0.103±0.030%/h) and WALK (0.118±0.037%/h) compared to SIT (0.080±0.032%/h). Compared to SIT, there were moderate-to-large effect sizes, respectively, for SQUAT (ES=0.75; 95% CI -0.10-1.55) and WALK (ES=1.10; 95% CI 0.20-1.91). Fold change in rpS6Ser240/244 phosphorylation was greater in SQUAT compared to SIT (7.6±2.7 vs. 1.6±0.45 fold, p<0.05) with no difference (p≥0.21) in any other targets measured (4E-BP1Thr37/46, eEF2Thr56, mTORSer2448, ERK1/2Thr202/Tyr204). Interrupting prolonged sitting with short 'activity snacks' improves the utilization of dietary amino acids for MyoPS. The long term impact of this practical lifestyle modification for muscle mass or quality should be investigated.
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Affiliation(s)
- Daniel R Moore
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Eric P Williamson
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Nathan Hodson
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Stephanie Estafanos
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Michael Mazzulla
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | | | - Jenna B Gillen
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
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Using the dual isotope method to assess cecal amino acid absorption of goat whey protein in rats, a pilot study. Amino Acids 2022; 54:811-821. [PMID: 35192060 DOI: 10.1007/s00726-022-03137-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 02/07/2022] [Indexed: 11/01/2022]
Abstract
Measurement of ileal amino acids (AA) bioavailability is recommended to evaluate protein quality. A dual isotope tracer method, based on plasma isotopic enrichment ratios, has been proposed to determine true digestibility in humans. In a pilot study, we aimed to evaluate whether this method could be implemented in rats to determine AA bioavailability based on isotopic enrichment ratios measured in cecal digesta or plasma samples. Goat milk proteins were intrinsically labeled with 15N and 2H. Wistar rats were fed a meal containing the doubly labeled goat whey proteins and a tracer dose of 13C-spirulina. Blood samples were collected 0, 1 h and 3 h after meal ingestion from the tail vein. The rats were euthanized 4 h (n = 6) or 6 h (n = 6) after meal to collect plasma and intestinal contents. True orocecal protein digestibility and AA bioavailability were assessed by means of 15N and 2H enrichment in cecum content and compared with absorption indexes determined at the plasma or cecum level using isotopic ratios. Plasma kinetics of isotopic enrichment could not be completed due to the limited quantity of plasma obtained with sequential blood collection. However, the absorption indexes determined from cecal 15N or 2H/13C ratios gave coherent values with true orocecal AA bioavailability. This dual isotope approach with measurements of isotopic ratios in digestive content could be an interesting strategy to determine true AA bioavailability in ileal digesta of rats.
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Simha V, Lanza IR, Dasari S, Klaus KA, Le Brasseur N, Vuckovic I, Laurenti MC, Cobelli C, Port JD, Nair KS. Impaired Muscle Mitochondrial Function in Familial Partial Lipodystrophy. J Clin Endocrinol Metab 2022; 107:346-362. [PMID: 34614176 PMCID: PMC8764358 DOI: 10.1210/clinem/dgab725] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Indexed: 01/04/2023]
Abstract
CONTEXT Familial partial lipodystrophy (FPL), Dunnigan variety is characterized by skeletal muscle hypertrophy and insulin resistance besides fat loss from the extremities. The cause for the muscle hypertrophy and its functional consequences is not known. OBJECTIVE To compare muscle strength and endurance, besides muscle protein synthesis rate between subjects with FPL and matched controls (n = 6 in each group). In addition, we studied skeletal muscle mitochondrial function and gene expression pattern to help understand the mechanisms for the observed differences. METHODS Body composition by dual-energy X-ray absorptiometry, insulin sensitivity by minimal modelling, assessment of peak muscle strength and fatigue, skeletal muscle biopsy and calculation of muscle protein synthesis rate, mitochondrial respirometry, skeletal muscle transcriptome, proteome, and gene set enrichment analysis. RESULTS Despite increased muscularity, FPL subjects did not demonstrate increased muscle strength but had earlier fatigue on chest press exercise. Decreased mitochondrial state 3 respiration in the presence of fatty acid substrate was noted, concurrent to elevated muscle lactate and decreased long-chain acylcarnitine. Based on gene transcriptome, there was significant downregulation of many critical metabolic pathways involved in mitochondrial biogenesis and function. Moreover, the overall pattern of gene expression was indicative of accelerated aging in FPL subjects. A lower muscle protein synthesis and downregulation of gene transcripts involved in muscle protein catabolism was observed. CONCLUSION Increased muscularity in FPL is not due to increased muscle protein synthesis and is likely due to reduced muscle protein degradation. Impaired mitochondrial function and altered gene expression likely explain the metabolic abnormalities and skeletal muscle dysfunction in FPL subjects.
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MESH Headings
- Absorptiometry, Photon
- Adult
- Aged
- Female
- Gene Expression Profiling
- Humans
- Lipodystrophy, Familial Partial/genetics
- Lipodystrophy, Familial Partial/metabolism
- Lipodystrophy, Familial Partial/pathology
- Lipodystrophy, Familial Partial/physiopathology
- Male
- Middle Aged
- Mitochondria, Muscle/metabolism
- Mitochondria, Muscle/pathology
- Muscle Strength/physiology
- Muscle, Skeletal/cytology
- Muscle, Skeletal/pathology
- Muscle, Skeletal/physiopathology
- Physical Endurance/physiology
- Proteolysis
- Young Adult
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Affiliation(s)
- Vinaya Simha
- Divisions of Endocrinology, Mayo Clinic, Rochester, MN 55905, USA
| | - Ian R Lanza
- Divisions of Endocrinology, Mayo Clinic, Rochester, MN 55905, USA
| | - Surendra Dasari
- Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905, USA
| | | | - Nathan Le Brasseur
- Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN 55905, USA
| | - Ivan Vuckovic
- Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | | | | | - John D Port
- Radiology, Mayo Clinic, Rochester, MN 55905, USA
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Abstract
Altered metabolic activity contributes to the pathogenesis of a number of diseases, including diabetes, heart failure, cancer, fibrosis and neurodegeneration. These diseases, and organismal metabolism more generally, are only partially recapitulated by cell culture models. Accordingly, it is important to measure metabolism in vivo. Over the past century, researchers studying glucose homeostasis have developed strategies for the measurement of tissue-specific and whole-body metabolic activity (pathway fluxes). The power of these strategies has been augmented by recent advances in metabolomics technologies. Here, we review techniques for measuring metabolic fluxes in intact mammals and discuss how to analyse and interpret the results. In tandem, we describe important findings from these techniques, and suggest promising avenues for their future application. Given the broad importance of metabolism to health and disease, more widespread application of these methods holds the potential to accelerate biomedical progress.
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Affiliation(s)
- Caroline R Bartman
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Chemistry, Princeton University, Princeton, NJ, USA
| | - Tara TeSlaa
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Chemistry, Princeton University, Princeton, NJ, USA
| | - Joshua D Rabinowitz
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.
- Department of Chemistry, Princeton University, Princeton, NJ, USA.
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Determination of Organochlorine Pesticide Residues in Some Evaporated Milk Samples in Nigeria Using Gas Chromatography-Mass Spectrometry. CHEMISTRY AFRICA 2021. [DOI: 10.1007/s42250-020-00224-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Monteyne AJ, Coelho MOC, Porter C, Abdelrahman DR, Jameson TSO, Finnigan TJA, Stephens FB, Dirks ML, Wall BT. Branched-Chain Amino Acid Fortification Does Not Restore Muscle Protein Synthesis Rates following Ingestion of Lower- Compared with Higher-Dose Mycoprotein. J Nutr 2020; 150:2931-2941. [PMID: 32886108 DOI: 10.1093/jn/nxaa251] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 06/18/2020] [Accepted: 07/29/2020] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND We have shown that ingesting a large bolus (70 g) of the fungal-derived, whole food mycoprotein robustly stimulates muscle protein synthesis (MPS) rates. OBJECTIVE The aim of this study was to determine if a lower dose (35 g) of mycoprotein enriched with branched-chain amino acids (BCAAs) stimulates MPS to the same extent as 70 g of mycoprotein in resistance-trained young men. METHODS Nineteen men [aged 22 ± 1 y, BMI (kg/m2): 25 ± 1] took part in a randomized, double-blind, parallel-group study. Participants received primed, continuous infusions of l-[ring-2H5]phenylalanine and ingested either 70 g mycoprotein (31.5 g protein; MYCO; n = 10) or 35 g BCAA-enriched mycoprotein (18.7 g protein: matched on BCAA content; ENR; n = 9) following a bout of unilateral resistance exercise. Blood and bilateral quadriceps muscle samples were obtained before exercise and protein ingestion and during a 4-h postprandial period to assess MPS in rested and exercised muscle. Two- and 3-factor ANOVAs were used to detect differences in plasma amino acid kinetics and mixed muscle fractional synthetic rates, respectively. RESULTS Postprandial plasma BCAA concentrations increased more rapidly and to a larger degree in ENR compared with MYCO. MPS increased with protein ingestion (P ≤ 0.05) but to a greater extent following MYCO (from 0.025% ± 0.006% to 0.057% ± 0.004% · h-1 in rested muscle, and from 0.024% ± 0.007% to 0.072% ± 0.005% · h-1 in exercised muscle; P < 0.0001) compared with ENR (from 0.031% ± 0.003% to 0.043% ± 0.005% · h-1 in rested muscle, and 0.027% ± 0.005% to 0.052% ± 0.005% · h-1 in exercised muscle; P < 0.01) ingestion. Postprandial MPS rates were greater in MYCO compared with ENR (P < 0.01). CONCLUSIONS The ingestion of lower-dose BCAA-enriched mycoprotein stimulates resting and postexercise MPS rates, but to a lesser extent compared with the ingestion of a BCAA-matched 70-g mycoprotein bolus in healthy young men. This trial was registered at clinicaltrials.gov as 660065600.
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Affiliation(s)
- Alistair J Monteyne
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Mariana O C Coelho
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Craig Porter
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA
| | - Doaa R Abdelrahman
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA
| | - Thomas S O Jameson
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | | | - Francis B Stephens
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Marlou L Dirks
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Benjamin T Wall
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
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Halil K, Meryem K. Plasma amino acid levels in a cohort of patients in Turkey with classical phenylketonuria. ASIAN BIOMED 2020. [DOI: 10.1515/abm-2020-0009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Background
In patients with phenylketonuria, the central nervous system is adversely affected by noncompliance with diet. The levels of phenylalanine and many different amino acids (AAs) in the plasma of patients with phenylketonuria can be measured simultaneously.
Objectives
To measure the blood plasma levels of neurotransmitter AAs in a cohort of patients in Sanliurfa province, Turkey, with phenylketonuria for use as a support parameter for the follow-up of patients.
Methods
The phenylketonurics that we followed (n = 100) were divided into 2 groups according to their compliance with their dietary treatment. Plasma AA analysis results of phenylketonurics were compared with those of healthy children in a control group (n = 50).
Results
In the diet incompliant group (n = 56), the mean levels of γ-aminobutyric acid (GABA; 0.96 ± 1.07 μmol/L) and glycine (305.1 ± 105.19 μmol/L) were significantly higher than those in the diet compliant group (n = 44; GABA P = 0.005, glycine P < 0.001) and in the control group (GABA and glycine P < 0.001), whereas the mean levels of glutamic acid (39.01 ± 22.94 μmol/L) and asparagine (39.3 ± 16.89 μmol/L) were lower (P < 0.001) in the diet incompliant group. A positive correlation was observed between the levels of phenylalanine and GABA and glycine. A negative relationship was found between the levels of phenylalanine and glutamic acid and asparagine.
Conclusions
A relationship exists between the levels of plasma phenylalanine in a cohort of phenylketonurics in Sanliurfa province, Turkey, and the levels of some excitatory and inhibitory AAs. Excitatory and inhibitory AA levels in plasma may be used as support parameters in the follow-up of patients with phenylketonuria.
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Affiliation(s)
- Kazanasmaz Halil
- Department of Pediatrics, Faculty of Medicine , Harran University , Sanliurfa , Turkey
| | - Karaca Meryem
- Department of Pediatric Metabolism Disorders, Faculty of Medicine , Harran University , Sanliurfa , Turkey
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Monteyne AJ, Coelho MOC, Porter C, Abdelrahman DR, Jameson TSO, Jackman SR, Blackwell JR, Finnigan TJA, Stephens FB, Dirks ML, Wall BT. Mycoprotein ingestion stimulates protein synthesis rates to a greater extent than milk protein in rested and exercised skeletal muscle of healthy young men: a randomized controlled trial. Am J Clin Nutr 2020; 112:318-333. [PMID: 32438401 DOI: 10.1093/ajcn/nqaa092] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 04/09/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Mycoprotein is a fungal-derived sustainable protein-rich food source, and its ingestion results in systemic amino acid and leucine concentrations similar to that following milk protein ingestion. OBJECTIVE We assessed the mixed skeletal muscle protein synthetic response to the ingestion of a single bolus of mycoprotein compared with a leucine-matched bolus of milk protein, in rested and exercised muscle of resistance-trained young men. METHODS Twenty resistance-trained healthy young males (age: 22 ± 1 y, body mass: 82 ± 2 kg, BMI: 25 ± 1 kg·m-2) took part in a randomized, double-blind, parallel-group study. Participants received primed, continuous infusions of L-[ring-2H5]phenylalanine and ingested either 31 g (26.2 g protein: 2.5 g leucine) milk protein (MILK) or 70 g (31.5 g protein: 2.5 g leucine) mycoprotein (MYCO) following a bout of unilateral resistance-type exercise (contralateral leg acting as resting control). Blood and m. vastus lateralis muscle samples were collected before exercise and protein ingestion, and following a 4-h postprandial period to assess mixed muscle fractional protein synthetic rates (FSRs) and myocellular signaling in response to the protein beverages in resting and exercised muscle. RESULTS Mixed muscle FSRs increased following MILK ingestion (from 0.036 ± 0.008 to 0.052 ± 0.006%·h-1 in rested, and 0.035 ± 0.008 to 0.056 ± 0.005%·h-1 in exercised muscle; P <0.01) but to a greater extent following MYCO ingestion (from 0.025 ± 0.006 to 0.057 ± 0.004%·h-1 in rested, and 0.024 ± 0.007 to 0.072 ± 0.005%·h-1 in exercised muscle; P <0.0001) (treatment × time interaction effect; P <0.05). Postprandial FSRs trended to be greater in MYCO compared with MILK (0.065 ± 0.004 compared with 0.054 ± 0.004%·h-1, respectively; P = 0.093) and the postprandial rise in FSRs was greater in MYCO compared with MILK (Delta 0.040 ± 0.006 compared with Delta 0.018 ± 0.005%·h-1, respectively; P <0.01). CONCLUSIONS The ingestion of a single bolus of mycoprotein stimulates resting and postexercise muscle protein synthesis rates, and to a greater extent than a leucine-matched bolus of milk protein, in resistance-trained young men. This trial was registered at clinicaltrials.gov as 660065600.
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Affiliation(s)
- Alistair J Monteyne
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Mariana O C Coelho
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Craig Porter
- Department of Surgery, University of Texas Medical Branch & Shriners Hospital for Children, Galveston, TX, USA
| | - Doaa R Abdelrahman
- Department of Surgery, University of Texas Medical Branch & Shriners Hospital for Children, Galveston, TX, USA
| | - Thomas S O Jameson
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Sarah R Jackman
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Jamie R Blackwell
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | | | - Francis B Stephens
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Marlou L Dirks
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Benjamin T Wall
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
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13
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Miller BF, Reid JJ, Price JC, Lin HJL, Atherton PJ, Smith K. CORP: The use of deuterated water for the measurement of protein synthesis. J Appl Physiol (1985) 2020; 128:1163-1176. [PMID: 32213116 DOI: 10.1152/japplphysiol.00855.2019] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The use of deuterium oxide (D2O) has greatly expanded the scope of what is possible for the measurement of protein synthesis. The greatest asset of D2O labeling is that it facilitates the measurement of synthesis rates over prolonged periods of time from single proteins through integrated tissue-based measurements. Because the ease of administration, the method is amenable for use in a variety of models and conditions. Although the method adheres to the same rules as other isotope methods, the flexibility can create conditions that are not the same as other approaches and thus requires careful execution to maintain validity and reliability. For this CORP article, we provide a history that gave rise to the method and discuss the advantages and disadvantages of the method, the critical assumptions, guidelines, and best practices based on instrumentation, models, and experimental design. The goal of this CORP article is to propagate additional use of D2O in a manner that produces reliable and valid data.
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Affiliation(s)
- Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - Justin J Reid
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - John C Price
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah
| | - Hsien-Jung L Lin
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah
| | - Philip J Atherton
- MRC-ARUK Center for Musculoskeletal Ageing Research, School of Medicine, University of Nottingham, Derby, United Kingdom
| | - Kenneth Smith
- MRC-ARUK Center for Musculoskeletal Ageing Research, School of Medicine, University of Nottingham, Derby, United Kingdom
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14
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Durak BY, Chormey DS, Firat M, Bakirdere S. Validation of ultrasonic-assisted switchable solvent liquid phase microextraction for trace determination of hormones and organochlorine pesticides by GC–MS and combination with QuEChERS. Food Chem 2020; 305:125487. [DOI: 10.1016/j.foodchem.2019.125487] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 06/10/2019] [Accepted: 09/04/2019] [Indexed: 01/03/2023]
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15
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Moran A, Toffolo G, Schiavon M, Vella A, Klaus K, Cobelli C, Nair KS. A novel triple-tracer approach to assess postprandial protein turnover. Am J Physiol Endocrinol Metab 2018; 315:E469-E477. [PMID: 29870679 PMCID: PMC6230707 DOI: 10.1152/ajpendo.00012.2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Insulin and nutrients have profound effects on proteome homeostasis. Currently no reliable methods are available to measure postprandial protein turnover. A triple-tracer method was developed using phenylalanine stable isotope tracers to estimate appearance rates of ingested (Ra meal) and endogenous phenylalanine and the rate of phenylalanine disposal (Rd). This was compared with the "traditional" dual-tracer method, using one (1-CM)- and two (2-CM)-compartment models. For both methods, [13C6]phenylalanine was given orally, and [15N]phenylalanine was constantly infused; the triple-tracer method added [2H5]phenylalanine, infused at rates to mimic meal [13C6]phenylalanine appearance. Additionally, incorporation of meal-derived phenylalanine into specific proteins was measured after purification by two-dimensional electrophoresis. The triple-tracer approach reduced modeling errors, allowing improved reconstruction of Ra meal with a tracer-to-tracee ratio that was more constant and better estimated Rd. The 2-CM better described phenylalanine kinetics and Rd than 1-CM. Thus, the triple-tracer approach using 2-CM is superior for measuring non-steady-state postprandial protein turnover. This novel approach also allows measurement of postprandial synthesis rates of specific plasma proteins. We offer a valid non-steady-state model to measure postprandial protein turnover and synthesis of plasma proteins that can safely be applied in adults, children, and pregnant women.
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Affiliation(s)
- Antoinette Moran
- Department of Pediatrics, University of Minnesota , Minneapolis, Minnesota
| | - Gianna Toffolo
- Department of Electronics and Informatics, University of Padova , Padova , Italy
| | - Michele Schiavon
- Department of Electronics and Informatics, University of Padova , Padova , Italy
| | - Adrian Vella
- Division of Endocrinology, Mayo Clinic , Rochester, Minnesota
| | - Katherine Klaus
- Division of Endocrinology, Mayo Clinic , Rochester, Minnesota
| | - Claudio Cobelli
- Department of Electronics and Informatics, University of Padova , Padova , Italy
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16
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Krämer L, Jäger C, Trezzi JP, Jacobs DM, Hiller K. Quantification of Stable Isotope Traces Close to Natural Enrichment in Human Plasma Metabolites Using Gas Chromatography-Mass Spectrometry. Metabolites 2018; 8:metabo8010015. [PMID: 29443915 PMCID: PMC5876004 DOI: 10.3390/metabo8010015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 02/07/2018] [Accepted: 02/08/2018] [Indexed: 01/08/2023] Open
Abstract
Currently, changes in metabolic fluxes following consumption of stable isotope-enriched foods are usually limited to the analysis of postprandial kinetics of glucose. Kinetic information on a larger diversity of metabolites is often lacking, mainly due to the marginal percentage of fully isotopically enriched plant material in the administered food product, and hence, an even weaker 13C enrichment in downstream plasma metabolites. Therefore, we developed an analytical workflow to determine weak 13C enrichments of diverse plasma metabolites with conventional gas chromatography-mass spectrometry (GC-MS). The limit of quantification was increased by optimizing (1) the metabolite extraction from plasma, (2) the GC-MS measurement, and (3) most importantly, the computational data processing. We applied our workflow to study the catabolic dynamics of 13C-enriched wheat bread in three human subjects. For that purpose, we collected time-resolved human plasma samples at 16 timepoints after the consumption of 13C-labeled bread and quantified 13C enrichment of 12 metabolites (glucose, lactate, alanine, glycine, serine, citrate, glutamate, glutamine, valine, isoleucine, tyrosine, and threonine). Based on isotopomer specific analysis, we were able to distinguish catabolic profiles of starch and protein hydrolysis. More generally, our study highlights that conventional GC-MS equipment is sufficient to detect isotope traces below 1% if an appropriate data processing is integrated.
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Affiliation(s)
- Lisa Krämer
- Department of Bioinformatics and Biochemistry, BRICS, Technische Universität Braunschweig, 38106 Braunschweig, Germany.
| | - Christian Jäger
- Luxembourg Centre for Systems Biomedicine, Université du Luxembourg, 4362 Esch-sur-Alzette, Luxembourg.
| | - Jean-Pierre Trezzi
- Luxembourg Centre for Systems Biomedicine, Université du Luxembourg, 4362 Esch-sur-Alzette, Luxembourg.
- Integrated Biobank of Luxembourg, Luxembourg Institute of Health, 3555 Dudelange, Luxembourg.
| | - Doris M Jacobs
- Unilever R&D Vlaardingen, 3133 AT Vlaardingen, The Netherlands.
| | - Karsten Hiller
- Department of Bioinformatics and Biochemistry, BRICS, Technische Universität Braunschweig, 38106 Braunschweig, Germany.
- Helmholtz Zentrum für Infektionsforschung, 38124 Braunschweig, Germany.
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17
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Wilkinson DJ. Historical and contemporary stable isotope tracer approaches to studying mammalian protein metabolism. MASS SPECTROMETRY REVIEWS 2018; 37:57-80. [PMID: 27182900 PMCID: PMC5763415 DOI: 10.1002/mas.21507] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 04/22/2016] [Indexed: 06/05/2023]
Abstract
Over a century ago, Frederick Soddy provided the first evidence for the existence of isotopes; elements that occupy the same position in the periodic table are essentially chemically identical but differ in mass due to a different number of neutrons within the atomic nucleus. Allied to the discovery of isotopes was the development of some of the first forms of mass spectrometers, driven forward by the Nobel laureates JJ Thomson and FW Aston, enabling the accurate separation, identification, and quantification of the relative abundance of these isotopes. As a result, within a few years, the number of known isotopes both stable and radioactive had greatly increased and there are now over 300 stable or radioisotopes presently known. Unknown at the time, however, was the potential utility of these isotopes within biological disciplines, it was soon discovered that these stable isotopes, particularly those of carbon (13 C), nitrogen (15 N), oxygen (18 O), and hydrogen (2 H) could be chemically introduced into organic compounds, such as fatty acids, amino acids, and sugars, and used to "trace" the metabolic fate of these compounds within biological systems. From this important breakthrough, the age of the isotope tracer was born. Over the following 80 yrs, stable isotopes would become a vital tool in not only the biological sciences, but also areas as diverse as forensics, geology, and art. This progress has been almost exclusively driven through the development of new and innovative mass spectrometry equipment from IRMS to GC-MS to LC-MS, which has allowed for the accurate quantitation of isotopic abundance within samples of complex matrices. This historical review details the development of stable isotope tracers as metabolic tools, with particular reference to their use in monitoring protein metabolism, highlighting the unique array of tools that are now available for the investigation of protein metabolism in vivo at a whole body down to a single protein level. Importantly, it will detail how this development has been closely aligned to the technological development within the area of mass spectrometry. Without the dedicated development provided by these mass spectrometrists over the past century, the use of stable isotope tracers within the field of protein metabolism would not be as widely applied as it is today, this relationship will no doubt continue to flourish in the future and stable isotope tracers will maintain their importance as a tool within the biological sciences for many years to come. © 2016 The Authors. Mass Spectrometry Reviews Published by Wiley Periodicals, Inc. Mass Spec Rev.
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Affiliation(s)
- Daniel James Wilkinson
- MRC‐ARUK Centre for Musculoskeletal Ageing Research, Clinical, Metabolic and Molecular PhysiologyUniversity of Nottingham, Royal Derby Hospital CentreDerbyUnited Kingdom
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18
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Lalia AZ, Dasari S, Robinson MM, Abid H, Morse DM, Klaus KA, Lanza IR. Influence of omega-3 fatty acids on skeletal muscle protein metabolism and mitochondrial bioenergetics in older adults. Aging (Albany NY) 2017; 9:1096-1129. [PMID: 28379838 PMCID: PMC5425117 DOI: 10.18632/aging.101210] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/17/2017] [Indexed: 12/18/2022]
Abstract
Omega-3 polyunsaturated fatty acids (n3-PUFA) are recognized for their anti-inflammatory effects and may be beneficial in the context of sarcopenia. We determined the influence of n3-PUFA on muscle mitochondrial physiology and protein metabolism in older adults. Twelve young (18-35 years) and older (65-85 years) men and women were studied at baseline. Older adults were studied again following n3-PUFA supplementation (3.9g/day, 16 weeks). Muscle biopsies were used to evaluate respiratory capacity (high resolution respirometry) and oxidant emissions (spectrofluorometry) in isolated mitochondria. Maximal respiration was significantly lower in older compared to young. n3-PUFA did not change respiration, but significantly reduced oxidant emissions. Participants performed a single bout of resistance exercise, followed by biopsies at 15 and 18 hours post exercise. Several genes involved in muscle protein turnover were significantly altered in older adults at baseline and following exercise, yet muscle protein synthesis was similar between age groups under both conditions. Following n3-PUFA supplementation, mixed muscle, mitochondrial, and sarcoplasmic protein synthesis rates were increased in older adults before exercise. n3-PUFA increased post-exercise mitochondrial and myofibrillar protein synthesis in older adults. These results demonstrate that n3-PUFA reduce mitochondrial oxidant emissions, increase postabsorptive muscle protein synthesis, and enhance anabolic responses to exercise in older adults.
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Affiliation(s)
- Antigoni Z. Lalia
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Surendra Dasari
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Matthew M. Robinson
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Hinnah Abid
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Dawn M. Morse
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Katherine A. Klaus
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Ian R. Lanza
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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Robinson MM, Dasari S, Karakelides H, Bergen HR, Nair KS. Release of skeletal muscle peptide fragments identifies individual proteins degraded during insulin deprivation in type 1 diabetic humans and mice. Am J Physiol Endocrinol Metab 2016; 311:E628-37. [PMID: 27436610 PMCID: PMC5142007 DOI: 10.1152/ajpendo.00175.2016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 07/13/2016] [Indexed: 12/16/2022]
Abstract
Insulin regulates skeletal muscle protein degradation, but the types of proteins being degraded in vivo remain to be determined due to methodological limitations. We present a method to assess the types of skeletal muscle proteins that are degraded by extracting their degradation products as low-molecular weight (LMW) peptides from muscle samples. High-resolution mass spectrometry was used to identify the original intact proteins that generated the LMW peptides, which we validated in rodents and then applied to humans. We deprived insulin from insulin-treated streptozotocin (STZ) diabetic mice for 6 and 96 h and for 8 h in type 1 diabetic humans (T1D) for comparison with insulin-treated conditions. Protein degradation was measured using activation of autophagy and proteasome pathways, stable isotope tracers, and LMW approaches. In mice, insulin deprivation activated proteasome pathways and autophagy in muscle homogenates and isolated mitochondria. Reproducibility analysis of LMW extracts revealed that ∼80% of proteins were detected consistently. As expected, insulin deprivation increased whole body protein turnover in T1D. Individual protein degradation increased with insulin deprivation, including those involved in mitochondrial function, proteome homeostasis, nDNA support, and contractile/cytoskeleton. Individual mitochondrial proteins that generated more LMW fragment with insulin deprivation included ATP synthase subunit-γ (+0.5-fold, P = 0.007) and cytochrome c oxidase subunit 6 (+0.305-fold, P = 0.03). In conclusion, identifying LMW peptide fragments offers an approach to determine the degradation of individual proteins. Insulin deprivation increases degradation of select proteins and provides insight into the regulatory role of insulin in maintaining proteome homeostasis, especially of mitochondria.
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Affiliation(s)
| | - Surendra Dasari
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota; and
| | | | - H Robert Bergen
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
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Prolonged Exposure of Primary Human Muscle Cells to Plasma Fatty Acids Associated with Obese Phenotype Induces Persistent Suppression of Muscle Mitochondrial ATP Synthase β Subunit. PLoS One 2016; 11:e0160057. [PMID: 27532680 PMCID: PMC4988792 DOI: 10.1371/journal.pone.0160057] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 07/13/2016] [Indexed: 01/12/2023] Open
Abstract
Our previous studies show reduced abundance of the β-subunit of mitochondrial H+-ATP synthase (β-F1-ATPase) in skeletal muscle of obese individuals. The β-F1-ATPase forms the catalytic core of the ATP synthase, and it is critical for ATP production in muscle. The mechanism(s) impairing β-F1-ATPase metabolism in obesity, however, are not completely understood. First, we studied total muscle protein synthesis and the translation efficiency of β-F1-ATPase in obese (BMI, 36±1 kg/m2) and lean (BMI, 22±1 kg/m2) subjects. Both total protein synthesis (0.044±0.006 vs 0.066±0.006%·h-1) and translation efficiency of β-F1-ATPase (0.0031±0.0007 vs 0.0073±0.0004) were lower in muscle from the obese subjects when compared to the lean controls (P<0.05). We then evaluated these same responses in a primary cell culture model, and tested the specific hypothesis that circulating non-esterified fatty acids (NEFA) in obesity play a role in the responses observed in humans. The findings on total protein synthesis and translation efficiency of β-F1-ATPase in primary myotubes cultured from a lean subject, and after exposure to NEFA extracted from serum of an obese subject, were similar to those obtained in humans. Among candidate microRNAs (i.e., non-coding RNAs regulating gene expression), we identified miR-127-5p in preventing the production of β-F1-ATPase. Muscle expression of miR-127-5p negatively correlated with β-F1-ATPase protein translation efficiency in humans (r = - 0.6744; P<0.01), and could be modeled in vitro by prolonged exposure of primary myotubes derived from the lean subject to NEFA extracted from the obese subject. On the other hand, locked nucleic acid inhibitor synthesized to target miR-127-5p significantly increased β-F1-ATPase translation efficiency in myotubes (0.6±0.1 vs 1.3±0.3, in control vs exposure to 50 nM inhibitor; P<0.05). Our experiments implicate circulating NEFA in obesity in suppressing muscle protein metabolism, and establish impaired β-F1-ATPase translation as an important consequence of obesity.
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21
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Burd NA, Tardif N, Rooyackers O, van Loon LJC. Optimizing the measurement of mitochondrial protein synthesis in human skeletal muscle. Appl Physiol Nutr Metab 2016; 40:1-9. [PMID: 25494678 DOI: 10.1139/apnm-2014-0211] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The measurement of mitochondrial protein synthesis after food ingestion, contractile activity, and/or disease is often used to provide insight into skeletal muscle adaptations that occur in the longer term. Studies have shown that protein ingestion stimulates mitochondrial protein synthesis in human skeletal muscle. Minor differences in the stimulation of mitochondrial protein synthesis occur after a single bout of resistance or endurance exercise. There appear to be no measurable differences in mitochondrial protein synthesis between critically ill patients and aged-matched controls. However, the mitochondrial protein synthetic response is reduced at a more advanced age. In this paper, we discuss the challenges involved in the measurement of human skeletal muscle mitochondrial protein synthesis rates based on stable isotope amino acid tracer methods. Practical guidelines are discussed to improve the reliability of the measurement of mitochondrial protein synthesis rates. The value of the measurement of mitochondrial protein synthesis after a single meal or exercise bout on the prediction of the longer term skeletal muscle mass and performance outcomes in both the healthy and disease populations requires more work, but we emphasize that the measurements need to be reliable to be of any value to the field.
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Affiliation(s)
- Nicholas A Burd
- a Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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22
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Zabielski P, Lanza IR, Gopala S, Heppelmann CJH, Bergen HR, Dasari S, Nair KS. Altered Skeletal Muscle Mitochondrial Proteome As the Basis of Disruption of Mitochondrial Function in Diabetic Mice. Diabetes 2016; 65:561-73. [PMID: 26718503 PMCID: PMC4764144 DOI: 10.2337/db15-0823] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 12/01/2015] [Indexed: 12/11/2022]
Abstract
Insulin plays pivotal role in cellular fuel metabolism in skeletal muscle. Despite being the primary site of energy metabolism, the underlying mechanism on how insulin deficiency deranges skeletal muscle mitochondrial physiology remains to be fully understood. Here we report an important link between altered skeletal muscle proteome homeostasis and mitochondrial physiology during insulin deficiency. Deprivation of insulin in streptozotocin-induced diabetic mice decreased mitochondrial ATP production, reduced coupling and phosphorylation efficiency, and increased oxidant emission in skeletal muscle. Proteomic survey revealed that the mitochondrial derangements during insulin deficiency were related to increased mitochondrial protein degradation and decreased protein synthesis, resulting in reduced abundance of proteins involved in mitochondrial respiration and β-oxidation. However, a paradoxical upregulation of proteins involved in cellular uptake of fatty acids triggered an accumulation of incomplete fatty acid oxidation products in skeletal muscle. These data implicate a mismatch of β-oxidation and fatty acid uptake as a mechanism leading to increased oxidative stress in diabetes. This notion was supported by elevated oxidative stress in cultured myotubes exposed to palmitate in the presence of a β-oxidation inhibitor. Together, these results indicate that insulin deficiency alters the balance of proteins involved in fatty acid transport and oxidation in skeletal muscle, leading to impaired mitochondrial function and increased oxidative stress.
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Affiliation(s)
- Piotr Zabielski
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| | - Ian R Lanza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| | - Srinivas Gopala
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| | | | - H Robert Bergen
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN
| | - Surendra Dasari
- Division of Biomedical Statistics and Informatics, Mayo Clinic College of Medicine, Rochester, MN
| | - K Sreekumaran Nair
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
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23
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Tran L, Masters H, Roust LR, Katsanos CS. A new method to measure muscle protein synthesis in humans by endogenously introduced d9-leucine and using blood for precursor enrichment determination. Physiol Rep 2015; 3:3/8/e12479. [PMID: 26243214 PMCID: PMC4562565 DOI: 10.14814/phy2.12479] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Enrichment from the easily accessible blood amino acid pool is commonly used as precursor enrichment to calculate rates of muscle protein fractional synthesis in relevant human studies in lieu of the less accessible muscle fluid amino acid pool. However, the accuracy of this approach depends largely on the extent to which there is low discrepancy in free amino acid enrichment between blood and muscle. Steady-state gradient (i.e., ratio) of amino acid enrichment between blood and muscle fluid in the basal state and in response to amino acid infusion were determined in five healthy subjects, and in association with two separate tracers: d9-leucine, introduced endogenously by the metabolism of d10-leucine (i.e., l-[2,3,3,4,5,5,5,6,6,6-(2)H10]leucine) infused in blood, and (13)C6-phenylalanine introduced/infused in blood. The blood-to-muscle fluid amino acid enrichment ratio was lower (P < 0.05) for d9-leucine compared to (13)C6-phenylalanine both before (1.5 ± 0.1 vs. 2.5 ± 0.1) and during (1.1 ± 0.1 vs. 1.2 ± 0.1) amino acid infusion. Importantly, the decrease in this ratio in association with the amino acid infusion was considerably less for the d9-leucine than the (13)C6-phenylalanine (-0.38 ± 0.03 vs. -1.29 ± 0.07; P < 0.05). In conclusion, blood d9-leucine enrichment introduced endogenously by intravenous infusion of d10-leucine provides a closer estimate of the muscle fluid amino acid enrichment, and its associated changes, than blood phenylalanine enrichment to calculate rates of muscle protein synthesis in humans.
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Affiliation(s)
- Lee Tran
- Center for Metabolic and Vascular Biology, Arizona State University, Tempe, Arizona, USA Mayo Clinic in Arizona, Scottsdale, Arizona, USA
| | - Haley Masters
- Center for Metabolic and Vascular Biology, Arizona State University, Tempe, Arizona, USA Mayo Clinic in Arizona, Scottsdale, Arizona, USA
| | - Lori R Roust
- Mayo Clinic in Arizona, Scottsdale, Arizona, USA
| | - Christos S Katsanos
- Center for Metabolic and Vascular Biology, Arizona State University, Tempe, Arizona, USA Mayo Clinic in Arizona, Scottsdale, Arizona, USA
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Hines KM, Ford GC, Klaus KA, Irving BA, Ford BL, Johnson KL, Lanza IR, Nair KS. Application of high-resolution mass spectrometry to measure low abundance isotope enrichment in individual muscle proteins. Anal Bioanal Chem 2015; 407:4045-52. [PMID: 25832482 PMCID: PMC4539943 DOI: 10.1007/s00216-015-8641-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 03/11/2015] [Accepted: 03/12/2015] [Indexed: 10/23/2022]
Abstract
Stable isotope-labeled amino acids have long been used to measure the fractional synthesis rate of proteins, although the mass spectrometry platforms used for such analyses have changed throughout the years. More recently, tandem mass spectrometers such as triple quadrupoles have been accepted as the standard platform for enrichment measurement due to their sensitivity and the enhanced specificity offered by multiple reaction monitoring (MRM) experiments. The limit in the utility of such platforms for enrichment analysis occurs when measuring very low levels of enrichment from small amounts of sample, particularly proteins isolated from two-dimensional gel electrophoresis (2D-GE), where interference from contaminant ions impacts the sensitivity of the measurement. We therefore applied a high-resolution orbitrap mass spectrometer to the analysis of [ring-(13)C6]-phenylalanine enrichment in individual muscle proteins isolated with 2D-GE. Comparison of samples analyzed on both platforms revealed that the high-resolution MS has significantly improved sensitivity relative to the triple quadrupole MS at very low-level enrichments due to its ability to resolve interferences in the m/z dimension. At higher enrichment levels, enrichment measurements from the orbitrap platform showed significant correlation (R (2) > 0.5) with those of the triple quadrupole platform. Together, these results indicate that high-resolution MS platforms such as the orbitrap are not only as capable of performing isotope enrichment measurements as the more commonly preferred triple quadrupole instruments, but offer unparalleled advantages in terms of mass accuracy and sensitivity in the presence of similar-mass contaminants.
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Affiliation(s)
- Kelly M. Hines
- Metabolomics Resource Core, Mayo Clinic, Rochester, MN 55905, USA
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN 55905, USA
| | - G. Charles Ford
- Metabolomics Resource Core, Mayo Clinic, Rochester, MN 55905, USA
| | - Katherine A. Klaus
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN 55905, USA
| | - Brian A. Irving
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN 55905, USA
| | - Beverly L. Ford
- Metabolomics Resource Core, Mayo Clinic, Rochester, MN 55905, USA
| | - Kenneth L. Johnson
- Medical Genome Facility Proteomics Core, Mayo Clinic, Rochester, MN 55905
| | - Ian R. Lanza
- Metabolomics Resource Core, Mayo Clinic, Rochester, MN 55905, USA
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN 55905, USA
| | - K. Sreekumaran Nair
- Metabolomics Resource Core, Mayo Clinic, Rochester, MN 55905, USA
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN 55905, USA
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Robinson MM, Soop M, Sohn TS, Morse DM, Schimke JM, Klaus KA, Nair KS. High insulin combined with essential amino acids stimulates skeletal muscle mitochondrial protein synthesis while decreasing insulin sensitivity in healthy humans. J Clin Endocrinol Metab 2014; 99:E2574-83. [PMID: 25222757 PMCID: PMC4255106 DOI: 10.1210/jc.2014-2736] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
CONTEXT Insulin and essential amino acids (EAAs) regulate skeletal muscle protein synthesis, yet their independent effects on mitochondrial protein synthesis (MiPS) and oxidative function remain to be clearly defined. OBJECTIVE The purpose of this study was to determine the effects of high or low insulin with or without EAAs on MiPS. DESIGN Thirty participants were randomized to 3 groups of 10 each with each participant studied twice. Study groups comprised (1) low and high insulin, (2) low insulin with and without EAAs, and (3) high insulin with and without EAAs. SETTING The study was conducted in an in-patient clinical research unit. PARTICIPANTS Eligible participants were 18 to 45 years old, had a body mass index of <25 kg/m(2), and were free of diseases and medications that might impair mitochondrial function. INTERVENTION Low (∼ 6 μU/mL) and high (∼ 40 μU/mL) insulin levels were maintained by iv insulin infusion during a somatostatin clamp while maintaining euglycemia (4.7-5.2 mM) and replacing GH and glucagon. The EAA infusion was 5.4% NephrAmine. l-[ring-(13)C6]Phenylalanine was infused, and muscle needle biopsies were performed. MAIN OUTCOMES Muscle MiPS, oxidative enzymes, and plasma amino acid metabolites were measured. RESULTS MiPS and oxidative enzyme activities did not differ between low and high insulin (MiPS: 0.07 ± 0.009 vs 0.07 ± 0.006%/h, P = .86) or between EAAs and saline during low insulin (MiPS: 0.05 ± 0.01 vs 0.07 ± 0.01, P = .5). During high insulin, EAAs in comparison with saline increased MiPS (0.1 ± 0.01 vs 0.06 ± 0.01, P < .05) and cytochrome c oxidase activity (P < .05) but not citrate synthase (P = .27). EAA infusion decreased (P < .05) the glucose infusion rates needed to maintain euglycemia during low (∼ 40%) and high insulin (∼ 24%). CONCLUSION EAAs increased MiPS and oxidative enzyme activity only with high insulin concentrations.
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Bornø A, Hulston CJ, van Hall G. Determination of human muscle protein fractional synthesis rate: an evaluation of different mass spectrometry techniques and considerations for tracer choice. JOURNAL OF MASS SPECTROMETRY : JMS 2014; 49:674-680. [PMID: 25044894 DOI: 10.1002/jms.3387] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 04/01/2014] [Accepted: 05/06/2014] [Indexed: 06/03/2023]
Abstract
In the present study, different MS methods for the determination of human muscle protein fractional synthesis rate (FSR) using [ring-(13)C6 ]phenylalanine as a tracer were evaluated. Because the turnover rate of human skeletal muscle is slow, only minute quantities of the stable isotopically labeled amino acid will be incorporated within the few hours of a typical laboratory experiment. GC combustion isotope ratio MS (GC-C-IRMS) has thus far been considered the 'gold' standard for the precise measurements of these low enrichment levels. However, advances in liquid chromatography-tandem MS (LC-MS/MS) and GC-tandem MS (GC-MS/MS) have made these techniques an option for human muscle FSR measurements. Human muscle biopsies were freeze dried, cleaned, and hydrolyzed, and the amino acids derivatized using either N-acetyl-n-propyl, phenylisothiocyanate, or N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) for GC-C-IRMS, LC-MS/MS, and GC-MS/MS analysis, respectively. A second derivative, heptafluorobutyric acid (HFBA), was also used for GC-MS/MS analysis as an alternative for MTBSTFA. The machine reproducibility or the coefficients of variation for delta tracer-tracee-ratio measurements (delta tracer-tracee-ratio values around 0.0002) were 2.6%, 4.1%, and 10.9% for GC-C-IRMS, LC-MS/MS, and GC-MS/MS (MTBSTFA), respectively. FSR determined with LC-MS/MS compared well with GC-C-IRMS and so did the GC-MS/MS when using the HFBA derivative (linear fit Y = 1.08 ± 0.10, X + 0.0049 ± 0.0061, r = 0.89 ± 0.01, P < 0.0001). In conclusion, (1) IRMS still offers the most precise measurement of human muscle FSR, (2) LC-MS/MS comes quite close and is a good alternative when tissue quantities are too small for GC-C-IRMS, and (3) If GC-MS/MS is to be used, then the HFBA derivative should be used instead of MTBSTFA, which gave unacceptably high variability.
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Affiliation(s)
- Andreas Bornø
- Rigshospitalet, Clinical Metabolomics Core Facility (CMCF), Section 7652, Ole Maaløesvej 26, 2100, Copenhagen Ø, Denmark
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