scholarly journals Impact of Protein Intake in Older Adults with Sarcopenia and Obesity: A Gut Microbiota Perspective

Nutrients ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2285 ◽  
Author(s):  
Konstantinos Prokopidis ◽  
Mavil May Cervo ◽  
Anoohya Gandham ◽  
David Scott
Keyword(s):  
Older Adults ◽  
Protein Synthesis ◽  
Fatty Acid ◽  
Gut Microbiota ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Chain Fatty Acid ◽  
Metabolic Effects ◽  
Population Increase ◽  
Skeletal Muscle Atrophy

The continuous population increase of older adults with metabolic diseases may contribute to increased prevalence of sarcopenia and obesity and requires advocacy of optimal nutrition treatments to combat their deleterious outcomes. Sarcopenic obesity, characterized by age-induced skeletal-muscle atrophy and increased adiposity, may accelerate functional decline and increase the risk of disability and mortality. In this review, we explore the influence of dietary protein on the gut microbiome and its impact on sarcopenia and obesity. Given the associations between red meat proteins and altered gut microbiota, a combination of plant and animal-based proteins are deemed favorable for gut microbiota eubiosis and muscle-protein synthesis. Additionally, high-protein diets with elevated essential amino-acid concentrations, alongside increased dietary fiber intake, may promote gut microbiota eubiosis, given the metabolic effects derived from short-chain fatty-acid and branched-chain fatty-acid production. In conclusion, a greater abundance of specific gut bacteria associated with increased satiation, protein synthesis, and overall metabolic health may be driven by protein and fiber consumption. This could counteract the development of sarcopenia and obesity and, therefore, represent a novel approach for dietary recommendations based on the gut microbiota profile. However, more human trials utilizing advanced metabolomic techniques to investigate the microbiome and its relationship with macronutrient intake, especially protein, are warranted.

scholarly journals Mechanisms Linking the Gut-Muscle Axis With Muscle Protein Metabolism and Anabolic Resistance: Implications for Older Adults at Risk of Sarcopenia

2021 ◽  
Vol 12 ◽  
Author(s):  
Konstantinos Prokopidis ◽  
Edward Chambers ◽  
Mary Ni Lochlainn ◽  
Oliver C. Witard
Keyword(s):  
Older Adults ◽  
Protein Synthesis ◽  
Amino Acid ◽  
Gut Microbiota ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Low Grade ◽  
Anabolic Resistance ◽  
Amino Acid Availability ◽  
Low Grade Inflammation

Aging is associated with a decline in skeletal muscle mass and function—termed sarcopenia—as mediated, in part, by muscle anabolic resistance. This metabolic phenomenon describes the impaired response of muscle protein synthesis (MPS) to the provision of dietary amino acids and practice of resistance-based exercise. Recent observations highlight the gut-muscle axis as a physiological target for combatting anabolic resistance and reducing risk of sarcopenia. Experimental studies, primarily conducted in animal models of aging, suggest a mechanistic link between the gut microbiota and muscle atrophy, mediated via the modulation of systemic amino acid availability and low-grade inflammation that are both physiological factors known to underpin anabolic resistance. Moreover, in vivo and in vitro studies demonstrate the action of specific gut bacteria (Lactobacillus and Bifidobacterium) to increase systemic amino acid availability and elicit an anti-inflammatory response in the intestinal lumen. Prospective lifestyle approaches that target the gut-muscle axis have recently been examined in the context of mitigating sarcopenia risk. These approaches include increasing dietary fiber intake that promotes the growth and development of gut bacteria, thus enhancing the production of short-chain fatty acids (SCFA) (acetate, propionate, and butyrate). Prebiotic/probiotic/symbiotic supplementation also generates SCFA and may mitigate low-grade inflammation in older adults via modulation of the gut microbiota. Preliminary evidence also highlights the role of exercise in increasing the production of SCFA. Accordingly, lifestyle approaches that combine diets rich in fiber and probiotic supplementation with exercise training may serve to produce SCFA and increase microbial diversity, and thus may target the gut-muscle axis in mitigating anabolic resistance in older adults. Future mechanistic studies are warranted to establish the direct physiological action of distinct gut microbiota phenotypes on amino acid utilization and the postprandial stimulation of muscle protein synthesis in older adults.

scholarly journals Ketogenic diet induces skeletal muscle atrophy via reducing muscle protein synthesis and possibly activating proteolysis in mice

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Reiko Nakao ◽  
Tomoki Abe ◽  
Saori Yamamoto ◽  
Katsutaka Oishi
Keyword(s):  
Oxidative Stress ◽  
Protein Synthesis ◽  
Muscle Atrophy ◽  
Muscle Wasting ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Metabolic Effects ◽  
Skeletal Muscle Atrophy ◽  
Ketogenic Diets ◽  
Underlying Mechanisms

AbstractKetogenic diets (KD) that are very high in fat and low in carbohydrates are thought to simulate the metabolic effects of starvation. We fed mice with a KD for seven days to assess the underlying mechanisms of muscle wasting induced by chronic starvation. This diet decreased the weight of the gastrocnemius (Ga), tibialis anterior (TA) and soleus (Sol) muscles by 23%, 11% and 16%, respectively. The size of Ga, TA, Sol muscle fibers and the grip strength of four limbs also significantly declined by 20%, 28%, 16% and 22%, respectively. The muscle atrophy-related genes Mafbx, Murf1, Foxo3, Lc3b and Klf15 were upregulated in the skeletal muscles of mice fed with the KD. In accordance with the reduced expression of anabolic genes such as Igf1, surface sensing of translation (SUnSET) analyses of fast-twitch Ga, TA and Sol muscles revealed that the KD suppressed muscle protein synthesis. The mRNA expression of oxidative stress-responsive genes such as Sod1 was significantly increased in all muscles examined. In addition to hypercorticosteronemia, hypoinsulinemia and reduced IGF-1, oxidative stress might also be involved in KD-induced muscle atrophy. Feeding mice with a KD is a novel experimental animal model of muscle-wasting induced by chronic starvation.

scholarly journals MECHANISMS IN ENDOCRINOLOGY: Exogenous insulin does not increase muscle protein synthesis rate when administered systemically: a systematic review

2015 ◽  
Vol 173 (1) ◽  
pp. R25-R34 ◽  
Author(s):  
Jorn Trommelen ◽  
Bart B L Groen ◽  
Henrike M Hamer ◽  
Lisette C P G M de Groot ◽  
Luc J C van Loon
Keyword(s):  
Systematic Review ◽  
Older Adults ◽  
Protein Synthesis ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Synthesis Rate ◽  
Protein Synthesis Rate ◽  
Exogenous Insulin ◽  
Insulin Administration ◽  
Muscle Protein Synthesis Rate

BackgroundThough it is well appreciated that insulin plays an important role in the regulation of muscle protein metabolism, there is much discrepancy in the literature on the capacity of exogenous insulin administration to increase muscle protein synthesis ratesin vivoin humans.ObjectiveTo assess whether exogenous insulin administration increases muscle protein synthesis rates in young and older adults.DesignA systematic review of clinical trials was performed and the presence or absence of an increase in muscle protein synthesis rate was reported for each individual study arm. In a stepwise manner, multiple models were constructed that excluded study arms based on the following conditions: model 1, concurrent hyperaminoacidemia; model 2, insulin-induced hypoaminoacidemia; model 3, supraphysiological insulin concentrations; and model 4, older, more insulin resistant, subjects.ConclusionsFrom the presented data in the current systematic review, we conclude that: i) exogenous insulin and amino acid administration effectively increase muscle protein synthesis, but this effect is attributed to the hyperaminoacidemia; ii) exogenous insulin administered systemically induces hypoaminoacidemia which obviates any insulin-stimulatory effect on muscle protein synthesis; iii) exogenous insulin resulting in supraphysiological insulin levels exceeding 50 000 pmol/l may effectively augment muscle protein synthesis; iv) exogenous insulin may have a diminished effect on muscle protein synthesis in older adults due to age-related anabolic resistance; and v) exogenous insulin administered systemically does not increase muscle protein synthesis in healthy, young adults.

scholarly journals Effect of Aerobic Exercise Training and Essential Amino Acid Supplementation for 24 Weeks on Physical Function, Body Composition, and Muscle Metabolism in Healthy, Independent Older Adults: A Randomized Clinical Trial

2018 ◽  
Vol 74 (10) ◽  
pp. 1598-1604 ◽  
Author(s):  
Melissa M Markofski ◽  
Kristofer Jennings ◽  
Kyle L Timmerman ◽  
Jared M Dickinson ◽  
Christopher S Fry ◽  
...  
Keyword(s):  
Older Adults ◽  
Clinical Trial ◽  
Body Composition ◽  
Protein Synthesis ◽  
Muscle Strength ◽  
Randomized Clinical Trial ◽  
Walking Speed ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Before And After

Abstract Background Essential amino acids (EAA) and aerobic exercise (AE) acutely and independently stimulate skeletal muscle protein anabolism in older adults. Objective In this Phase 1, double-blind, placebo-controlled, randomized clinical trial, we determined if chronic EAA supplementation, AE training, or a combination of the two interventions could improve muscle mass and function by stimulating muscle protein synthesis. Methods We phone-screened 971, enrolled 109, and randomized 50 independent, low-active, nonfrail, and nondiabetic older adults (age 72 ± 1 years). We used a 2 × 2 factorial design. The interventions were: daily nutritional supplementation (15 g EAA or placebo) and physical activity (supervised AE training 3 days/week or monitored habitual activity) for 24 weeks. Muscle strength, physical function, body composition, and muscle protein synthesis were measured before and after the 24-week intervention. Results Forty-five subjects completed the 24-week intervention. VO2peak and walking speed increased (p < .05) in both AE groups, irrespective of supplementation type, but muscle strength increased only in the EAA + AE group (p < .05). EAA supplementation acutely increased (p < .05) muscle protein synthesis from basal both before and after the intervention, with a larger increase in the EAA + AE group after the intervention. Total and regional lean body mass did not change significantly with any intervention. Conclusions In nonfrail, independent, healthy older adults AE training increased walking speed and aerobic fitness, and, when combined with EAA supplementation, it also increased muscle strength and EAA-stimulated muscle protein synthesis. These increases occurred without improvements in muscle mass.

scholarly journals Inadequacy of Protein Intake in Older UK Adults

Geriatrics ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 6 ◽  
Author(s):  
Susan Morris ◽  
James D. Cater ◽  
Mark A. Green ◽  
Alexandra M. Johnstone ◽  
Jeffrey M. Brunstrom ◽  
...  
Keyword(s):  
Older Adults ◽  
Protein Synthesis ◽  
Protein Intake ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Adult Population ◽  
Specific Recommendation ◽  
Food Diaries ◽  
The Uk ◽  
Older Adult Population

The current dietary recommendation for protein intake in the UK is 0.75 g/kg/day, however, this population-wide recommendation does not necessarily reflect altered requirements for older adults to maintain muscle protein synthesis, nor does it encompass the potential impact of intake timing. Optimal muscle protein synthesis in older adults requires both higher intake requirements and a distribution of protein intake above a 25 g threshold, three times across the day. This study aimed to describe the protein intake of older adults in a UK region and compare the results to recommendations. The study re-assessed two existing datasets with rich diet information for older adults in the South Yorkshire area. Data were extracted from food diaries of 256 adults aged between 65 and 89 years old (mean ± SD 72.4 ± 5.3 years). Quantity and timing of intake were coded using Nutritics software and compared to recommendations. The relationship between body mass index (BMI), age, and protein intake was explored. Fewer than 50% of the participants met current UK recommendations (0.75 g/kg/day) and fewer than 15% met the ESPEN 1.2 g/kg/day age-specific recommendation. Only one participant met the 25 g/meal recommendation across three meals. These findings suggest that the older adult population is not achieving recommendations to maintain muscle protein synthesis. Nonetheless it identifies several straightforward opportunities for improvement, notably elevation of morning intake.

scholarly journals Z-ajoene from Crushed Garlic Alleviates Cancer-Induced Skeletal Muscle Atrophy

Nutrients ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2724 ◽  
Author(s):  
Hyejin Lee ◽  
Ji-Won Heo ◽  
A-Reum Kim ◽  
Minson Kweon ◽  
Sorim Nam ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Protein Synthesis ◽  
Muscle Atrophy ◽  
Cancer Cachexia ◽  
Inflammatory Responses ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Janus Kinase ◽  
Skeletal Muscle Atrophy ◽  
E3 Ligases

Skeletal muscle atrophy is one of the major symptoms of cancer cachexia. Garlic (Allium sativum), one of the world’s most commonly used and versatile herbs, has been employed for the prevention and treatment of diverse diseases for centuries. In the present study, we found that ajoene, a sulfur compound found in crushed garlic, exhibits protective effects against muscle atrophy. Using CT26 tumor-bearing BALB/c mice, we demonstrate in vivo that ajoene extract alleviated muscle degradation by decreasing not only myokines secretion but also janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) and SMADs/forkhead box (FoxO) signaling pathways, thereby suppressing muscle-specific E3 ligases. In mouse skeletal myoblasts, Z-ajoene enhanced myogenesis as evidenced by increased expression of myogenic markers via p38 mitogen-activated protein kinase (MAPK) activation. In mature myotubes, Z-ajoene protected against muscle protein degradation induced by conditioned media from CT26 colon carcinoma cells, by suppressing expression of muscle specific E3 ligases and nuclear transcription factor kappa B (NF-κB) phosphorylation which contribute to muscle atrophy. Moreover, Z-ajoene treatment improved myofiber formation via stimulation of muscle protein synthesis. These findings suggest that ajoene extract and Z-ajoene can attenuate skeletal muscle atrophy induced by cancer cachexia through suppressing inflammatory responses and the muscle wasting as well as by promoting muscle protein synthesis.

Short Term Albuterol Administration Induces a Marked Increase in Muscle Protein Synthesis in Older Adults

2010 ◽  
Vol 42 ◽  
pp. 75-76
Author(s):  
Charles Paul Lambert ◽  
B. Selma Mohammed ◽  
Dennis T. Villareal ◽  
Linda R. Peterson ◽  
Brian N. Finck ◽  
...  
Keyword(s):  
Older Adults ◽  
Protein Synthesis ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Short Term

Dietary protein considerations for muscle protein synthesis and muscle mass preservation in older adults

2020 ◽  
pp. 1-11 ◽  
Author(s):  
Eunice T. Olaniyan ◽  
Fiona O’Halloran ◽  
Aoife L. McCarthy
Keyword(s):  
Older Adults ◽  
Protein Synthesis ◽  
Amino Acid ◽  
Muscle Mass ◽  
Protein Intake ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Adult Population ◽  
Anabolic Resistance

Abstract Amino acid bioavailability is critical for muscle protein synthesis (MPS) and preservation of skeletal muscle mass (SMM). Ageing is associated with reduced responsiveness of MPS to essential amino acids (EAA). Further, the older adult population experiences anabolic resistance, leading to increased frailty, functional decline and depleted muscle mass preservation, which facilitates the need for increased protein intake to increase their SMM. This review focuses on the role of proteins in muscle mass preservation and examines the contribution of EAA and protein intake patterns to MPS. Leucine is the most widely studied amino acid for its role as a potent stimulator of MPS, though due to inadequate data little is yet known about the role of other EAA. Reaching a conclusion on the best pattern of protein intake has proven difficult due to conflicting studies. A mixture of animal and plant proteins can contribute to increased MPS and potentially attenuate muscle wasting conditions; however, there is limited research on the biological impact of protein blends in older adults. While there is some evidence to suggest that liquid protein foods with higher than the RDA of protein may be the best strategy for achieving high MPS rates in older adults, clinical trials are warranted to confirm an association between food form and SMM preservation. Further research is warranted before adequate recommendations and strategies for optimising SMM in the elderly population can be proposed.

Sign in / Sign up

Export Citation Format

Share Document