Nutrition and physical performance in older people-effects of marine protein hydrolysates to prevent decline in physical performance: a randomised controlled trial protocol

Potential of Food Protein-Derived Bioactive Peptides against Sarcopenia: A Comprehensive Review

Sarcopenia is an age-related progressive muscle disorder characterized by accelerated loss of muscle mass, strength, and function, which are important causes of physiological dysfunctions in the elderly. At present, the main alleviating method includes protein supplements to stimulate synthesis of muscle proteins. Food protein-derived peptides containing abundant branched-chain amino acids have a remarkable effect on the improvement of sarcopenia. Understanding the underlying molecular mechanism and clarifying the structure-activity relationship is essential for the mitigation of sarcopenia. This present review recaps the epidemiology, pathogenesis, diagnosis, and treatment of sarcopenia, which facilitates a comprehensive understanding of sarcopenia. Moreover, the latest research progress on food-derived antisarcopenic peptides is reviewed, including their antisarcopenic activity, molecular mechanism as well as structural characteristics. Food-derived bioactive peptides can indeed alleviate/mitigate sarcopenia. These antisarcopenic peptides play a pivotal role mainly by activating the PI3K/Akt/mTOR and MAPK pathways and inhibiting the ubiquitin-proteasome system and AMPK pathway, thus promoting the synthesis of muscle proteins and inhibiting their degradation. Antisarcopenic peptides alleviate sarcopenia via specific peptides, which may be absorbed into the circulation and exhibit their bioactivity in intact forms. The present review provides a theoretical reference for mitigation and prevention of sarcopenia by food protein-derived bioactive peptides.

Sarcopenia; functional concerns, molecular mechanisms involved, and seafood as a nutritional intervention - review article

The fundamental basis for the human function is provided by skeletal muscle. Advancing age causes selective fiber atrophy, motor unit loss, and hybrid fiber formation resulting in hampered mass and strength, thus referred to as sarcopenia. Influence on the loss of independence of aged adults, contribute toward inclined healthcare costs conveys the injurious impact. The current understating of age-related skeletal muscle changes are addressed in this review, and further discusses mechanisms regulating protein turnover, although they do not completely define the process yet. Moreover, the reduced capacity of muscle regeneration due to impairment of satellite cell activation and proliferation with neuronal, immunological, hormonal factors were brought into the light of attention. Nevertheless, complete understating of sarcopenia requires disentangling it from disuse and disease. Nutritional intervention is considered a potentially preventable factor contributing to sarcopenia. Seafood is a crucial player in the fight against hunger and malnutrition, where it consists of macro and micronutrients. Hence, the review shed light on seafood as a nutritional intrusion in the treatment and prevention of sarcopenia. Understanding multiple factors will provide therapeutic targets in the prevention, treatment, and overcoming adverse effects of sarcopenia.

The role of protein hydrolysates for exercise-induced skeletal muscle recovery and adaptation: a current perspective

The protein supplement industry is expanding rapidly and estimated to have a multi-billion market worth. Recent research has centred on understanding how the manufacturing processes of protein supplements may impact muscle recovery and remodeling. The hydrolysed forms of protein undergo a further heating extraction process during production which may contribute to amino acids (AA) appearing in circulation at a slightly quicker rate, or greater amplitude, than the intact form. Whilst the relative significance of the rate of aminoacidemia to muscle protein synthesis is debated, it has been suggested that protein hydrolysates, potentially through the more rapid delivery and higher proportion of di-, tri- and smaller oligo-peptides into circulation, are superior to intact non-hydrolysed proteins and free AAs in promoting skeletal muscle protein remodeling and recovery. However, despite these claims, there is currently insufficient evidence to support superior muscle anabolic properties compared with intact non-hydrolysed proteins and/or free AA controls. Further research is warranted with appropriate protein controls, particularly in populations consuming insufficient amounts of protein, to support and/or refute an important muscle anabolic role of protein hydrolysates. The primary purpose of this review is to provide the reader with a current perspective on the potential anabolic effects of protein hydrolysates in individuals wishing to optimise recovery from, and maximise adaptation to, exercise training.

Limited Benefit of Marine Protein Hydrolysate on Physical Function and Strength in Older Adults: A Randomized Controlled Trial

Age-related muscle wasting can compromise functional abilities of the elderly. Protein intake stimulates muscle protein synthesis; however, ageing muscle is more resistant to stimuli. This double-blinded, randomized, controlled trial is one of the first registered studies to evaluate the effects of a supplement of marine protein hydrolysate (MPH) on measures of physical function and strength. Eighty-six older adults received nutritional supplements containing 3 g of MPH or a placebo for up to 12 months. Short Physical Performance Battery (SPPB), grip strength and gait speed were measured, and dietary intake was registered at baseline, 6 months, and 12 months. No difference was found between the intervention and control groups in mean change in SPPB (independent sample t-test, p = 0.41) or regarding time trend in SPPB, grip strength, or gait speed (linear mixed model). The participants in our study were well functioning, causing a ceiling effect in SPPB. Further, they had sufficient protein intake and were physically active. Differences in physical function between those completing the intervention and the dropouts might also have created bias in the results. We recommend that future studies of MPH be carried out on a more frail or malnourished population.

Protein Intake, Protein Mealtime Distribution and Seafood Consumption in Elderly Norwegians: Associations with Physical Function and Strength

Protein intake is considered important in the maintenance of muscle health in ageing. However, both the source and mealtime distribution of protein might affect the intake of protein and its effect on muscle protein synthesis. In this study, protein intake, mealtime distribution of protein, and seafood consumption were assessed in 92 older adults (aged 65+), and associations with physical performance (Short Physical Performance Battery (SPPB)), grip strength and gait speed were assessed in a multiple linear regression analysis. The participants had a mean age of 73 ± 8.9 years. Mean protein intake was 1.1 g/kg body weight. Protein intake was well distributed, with coefficient of variance between meals (CV meals) 0.6 ± 0.3. However, dinner had the highest protein intake. No associations were found between the nutrition factors and physical performance or strength; however, this result might have been caused by a ceiling effect in the chosen test batteries, as the mean score on SPPB was 10.3 ± 2.7, and 48.9% of the participants reached the top score of 12 points. Mean grip strength was 44.4 ± 9.4 kg (men) and 26.2 ± 6.8 kg (women). Mean gait speed was 1.0 ± 0.3 m/s. The interaction analysis suggests that there might be gender differences in the effect of seafood consumption on gait speed.

Marine Bioactive Peptides-An Overview of Generation, Structure and Application with a Focus on Food Sources

The biggest obstacles in the application of marine peptides are two-fold, as in the case of non-marine plant and animal-derived bioactive peptides: elucidating correlation between the peptide structure and its effect and demonstrating its stability in vivo. The structures of marine bioactive peptides are highly variable and complex and dependent on the sources from which they are isolated. They can be cyclical, in the form of depsipeptides, and often contain secondary structures. Because of steric factors, marine-derived peptides can be resistant to proteolysis by gastrointestinal proteases, which presents an advantage over other peptide sources. Because of heterogeneity, amino acid sequences as well as preferred mechanisms of peptides showing specific bioactivities differ compared to their animal-derived counterparts. This review offers insights on the extreme diversity of bioactivities, effects, and structural features, analyzing 253 peptides, mainly from marine food sources. Similar to peptides in food of non-marine animal origin, a significant percentage (52.7%) of the examined sequences contain one or more proline residues, implying that proline might play a significant role in the stability of bioactive peptides. Additional problems with analyzing marine-derived bioactive peptides include their accessibility, extraction, and purification; this review considers the challenges and proposes possible solutions.

The Potential Role of Fish-Derived Protein Hydrolysates on Metabolic Health, Skeletal Muscle Mass and Function in Ageing

Fish protein represents one of the most widely consumed dietary protein sources by humans. The processing of material from the fishing industry generates substantial unexploited waste products, many of which possess high biological value. Protein hydrolysates, such as fish protein hydrolysates (FPH), containing predominantly di- and tripeptides, are more readily absorbed than free amino acids and intact protein. Furthermore, in animal models, FPH have been shown to possess numerous beneficial properties for cardiovascular, neurological, intestinal, renal, and immune health. Ageing is associated with the loss of skeletal muscle mass and function, as well as increased oxidative stress, compromised vascularisation, neurological derangements, and immunosenescence. Thus, there appears to be a potential application for FPH in older persons as a high-quality protein source that may also confer additional health benefits. Despite this, there remains a dearth of information concerning the impact of FPH on health outcomes in humans. The limited evidence from human interventional trials suggests that FPH may hold promise for supporting optimal body composition and maintaining gut integrity. FPH also provide a high-quality source of dietary protein without negatively impacting on subjective appetite perceptions or regulatory hormones. Further studies are needed to assess the impact and utility of FPH on skeletal muscle health in older persons, ideally comparing FPH to ‘established’ protein sources or a non-bioactive, nitrogen-matched control. In particular, the effects of acute and chronic FPH consumption on post-exercise aminoacidaemia, skeletal muscle protein synthesis, and intramyocellular anabolic signalling in older adults are worthy of investigation. FPH may represent beneficial and sustainable alternative sources of high-quality protein to support skeletal muscle health and anabolism in ageing, without compromising appetite and subsequent energy intake.

A Review of the Development and Application of Generic Preference-Based Instruments with the Older Population

Older people (aged 65 years and over) are the fastest growing age cohort in the majority of developed countries, and the proportion of individuals defined as the oldest old (aged 80 years and over) living with physical frailty and cognitive impairment is rising. These population changes put increasing pressure on health and aged care services, thus it is important to assess the cost effectiveness of interventions targeted for older people across health and aged care sectors to identify interventions with the strongest capacity to enhance older peoples' quality of life and provide value for money. Cost-utility analysis (CUA) is a form of economic evaluation that typically uses preference-based instruments to measure and value health-related quality of life for the calculation of quality-adjusted life-years (QALYS) to enable comparisons of the cost effectiveness of different interventions. A variety of generic preference-based instruments have been used to measure older people's quality of life, including the Adult Social Care Outcomes Toolkit (ASCOT); Health Utility Index Mark 2 (HUI2); Health Utility Index Mark 3 (HUI3); Short-Form-6 Dimensions (SF-6D); Assessment of Quality of Life-6 dimensions (AQoL-6D); Assessment of Quality of Life-8 dimensions (AQoL-8D); Quality of Wellbeing Scale-Self-Administered (QWB-SA); 15 Dimensions (15D); EuroQol-5 dimensions (EQ-5D); and an older person specific preference-based instrument-the Investigating Choice Experiments Capability Measure for older people (ICECAP-O). This article reviews the development and application of these instruments within the older population and discusses the issues surrounding their use with this population. Areas for further research relating to the development and application of generic preference-based instruments with populations of older people are also highlighted.

In Vitro and In Silico Approaches to Generating and Identifying Angiotensin-Converting Enzyme I Inhibitory Peptides from Green Macroalga Ulva lactuca

A protein extract was generated from the macroalga Ulva lactuca, which was subsequently hydrolysed using the food-grade enzyme papain and angiotensin-converting Enzyme I and renin inhibitory peptides identified using a combination of enrichment strategies employing molecular weight cutoff filtration and mass spectrometry analysis. The generated hydrolysates with the most promising in vitro activity were further purified using preparative RP-HPLC and characterised. The 1 kDa hydrolysate (1 kDa-UFH), purified and collected by preparative RP-HPLC at minutes 41‒44 (Fr41‒44), displayed statistically higher ACE-I inhibitory activities ranging from 96.91% to 98.06%. A total of 48 novel peptides were identified from these four fractions by LC-MS/MS. A simulated gastrointestinal digestion of the identified peptide sequences was carried out using in silico enzyme cleavage simulation tools, resulting in 86 peptide sequences that were further assessed for their potential activity, toxicity and allergenicity using multiple predictive approaches. All the peptides obtained in this study were predicted to be non-toxic. However, 28 out of the 86 novel peptides released after the in silico gastrointestinal digestion were identified as potential allergens. The potential allergenicity of these peptides should be further explored to comply with the current labelling regulations in formulated food products containing U. lactuca protein hydrolysates.