The effects of collagen peptide supplementation on body composition, collagen synthesis, and recovery from joint injury and exercise: a systematic review

Role of METTL16 in PPARγ methylation and osteogenic differentiation

Osteoporosis, a prevalent bone disease, is characterized by the deterioration of bone tissue microstructure and imbalanced osteogenesis. The regulatory role of PPARγ m6A methylation mediated by METTL16 remains poorly elucidated. This study utilized advanced single-cell RNA sequencing (scRNA-seq) and Bulk RNA-seq techniques to explore how METTL16 influences the osteogenic differentiation of Bone Marrow-Derived Mesenchymal Stem Cells (BMSCs) and its implication in osteoporosis. The research revealed that METTL16 enhances the suppression of osteogenic differentiation in BMSCs, while PPARγ is associated with BMSC ferroptosis. Mechanistically, METTL16 facilitates the m6A modification of PPARγ transcription, thereby promoting ferroptosis in BMSCs and impeding their osteogenic differentiation. The in vivo animal experiments confirmed the pivotal role of the METTL16-PPARγ axis in osteoporosis development in mice. These findings suggest that the regulation of PPARγ m6A methylation by METTL16, leading to ferroptosis, is a critical mechanism impacting BMSC osteogenic differentiation and the pathogenesis of osteoporosis.

Structural Adaptations of the Anterolateral Complex of the Knee and Associated Tissues: A Comparative Anatomical and Histological Analysis of Knees With and Without an Anterolateral Ligament

The anterolateral ligament (ALL) is considered a secondary stabilizer of internal rotation and, due to proximity to the lateral collateral ligament (LCL), it may contribute to anterolateral rotatory stability. This study characterized the anatomy of the ALL and associated tissues of the anterolateral complex (ALC) to determine if structural and histological compensatory adaptations exist in patients without an ALL. Forty-nine cadaveric knees were dissected from distal-to-proximal using established landmarks with the aid of internal rotation stress to localize the ALL (if present), LCL, iliotibial band (ITB), and anterolateral capsule. The width and thickness of ALL and LCL were measured with digital calipers at the origin, middle, and insertion, and cross-sectional areas were calculated. ALL and LCL length and ITB thickness were also obtained. Samples of each tissue were stained with hematoxylin and eosin and picrosirius red, and histological images were evaluated with ImageJ to quantify collagen density (mean gray value [mgv]) and quantity (percent coverage). Size measurements and collagen characteristics were compared between ALL-present and ALL-deficient knees. The ALL was identified in 63% of knees with mean cross-sectional areas of 8.9, 5.8, and 9.7 mm2 at the origin, middle, and insertion, respectively. Mean collagen density of the ALL was 106.9 mgv on a scale of 0 (black) to 255 (white), and overall collagen quantity was 40.3%. Proximal LCL width (p = 0.04), distal LCL thickness (p = 0.03), and cross-sectional area (p = 0.01), and ITB thickness (p = 0.02) were significantly greater in ALL-deficient knees. A significantly higher collagen density was found within the LCL (p = 0.04), and higher overall quantity of collagen within the LCL (p < 0.01) and ITB (p < 0.01), of ALL-deficient knees. Gross anatomical and histological alterations exist in knees without an ALL compared with those with an ALL. These may reflect adaptations in the ALC and LCL that are present to compensate for the absence of the anterolateral rotatory stability afforded by the ALL.

Habitual Dietary Collagen Intake Is Lower in Females and Older Irish Adults Compared with Younger Males

BACKGROUND

Collagen ingestion reportedly benefits connective tissues, such as skin, bone, muscle, tendon, and ligament. However, the quantity of collagen intake in the diet of European adults is unknown.

OBJECTIVES

This study aims to investigate collagen intake in the habitual diets of Irish adults, and whether it differed according to sex and/or age.

METHODS

We conducted secondary analysis of the Irish National Adult Nutrition Survey, which assessed typical dietary intake using a 4-d food diary in 1500 adults, aged 18-90 y. We categorized participants into 3 age groups: young (18-39 y, n = 630), middle-aged (40-64 y, n = 644), and older (≥65 y, n = 226) adults. Collagen composition of each individual food item in the database was determined by applying a percentage collagen value from analytical sources, allowing computation of collagen mean daily intake (MDI), collagen MDI relative to body mass, and collagen/total protein MDI. Differences in intakes between age groups and sexes were evaluated using physical activity level as a covariate.

RESULTS

Collagen MDI for the entire population was 3.2 ± 2.0 g/d, representing 3.6% ± 1.9% total protein intake. Males had higher absolute and relative collagen MDI than females, regardless of age (4.0 ± 2.1 g/d compared with 2.3 ± 1.4 g/d, P < 0.001), whereas older adults had lower absolute collagen MDI than middle-aged adults (2.9 ± 1.8 g/d compared with 3.3 ± 2.0 g/d, P = 0.021).

CONCLUSIONS

Collagen intake in the Irish adult population was considered low (relative to total protein intake and to dose-response studies), particularly in females and older individuals. Increasing daily collagen intake may therefore be warranted to optimize the health of collagen-rich tissues.

The Effects of Type I Collagen Hydrolysate Supplementation on Bones, Muscles, and Joints: A Systematic Review

Introduction

Musculoskeletal discomfort is prevalent in primary care, with conditions such as osteoarthritis and osteoporosis being significant contributors. Collagen, particularly type I, is a major structural protein found in connective tissues. The supplementation of type I hydrolyzed collagen has been investigated for its potential benefits in musculoskeletal health.

Objective

This systematic review aims to evaluate the current literature on the effects of type I hydrolyzed collagen supplementation on bones, muscles, and joints.

Methods

A systematic search was conducted in August 2024 using four electronic databases - PubMed, Scopus, EMBASE, and CINAHL. The inclusion criteria were randomized controlled trials (RCTs) and systematic reviews evaluating oral supplementation with type I hydrolyzed collagen. Exclusion criteria were pre-clinical studies, experimental studies, studies not focusing on type I hydrolyzed collagen, studies with beauty-related endpoints, studies that combined collagen with other ingredients, and unblinded, nonrandomized, and uncontrolled trials.

Results

Out of 4,246 articles screened, 36 RCTs met the inclusion criteria. The study protocols varied in population, health conditions, and study duration. Studies focused on bone health faced limitations that prevent definitive conclusions about the effects of collagen supplementation. In contrast, studies on joint health reported beneficial outcomes, such as pain reduction, improvements in clinical parameters, increased physical mobility, and enhanced ankle function. The muscle health studies were inconsistent, with positive effects predominantly observed when supplementation was associated with physical exercise.

Conclusion

Collagen supplementation demonstrates promising results. However, heterogeneity among studies limits the generalizability of findings. Future research should prioritize standardized protocols and consistent outcome measures.

Injectable Therapeutic Peptides-An Adjunct to Regenerative Medicine and Sports Performance?

High-level athletes and bodybuilders are constantly seeking novel therapies to enhance recovery and expedite return from injury-injectable peptides are a new and trending therapy that may be the wave of the future in the realm of regenerative medicine research in treating joint injuries and osteoarthritis. Very early in vivo research on pharmacokinetics indicates the possibility that body protection compound 157 (BPC-157) is at the forefront of therapeutic peptides, with early demonstrations of this experimental peptide optimizing endurance training, metabolism, recovery, and tissue repair. Although unregulated and yet readily available for purchase over the internet, there is scarce orthopaedic literature investigating the clinical use and outcomes of such therapeutic peptides in tendon, muscle, and cartilage injury. However, this has not slowed the recent exponential growth of the multi-billion-dollar industry in the development of therapeutic peptides. As orthopaedic surgeons and team physicians, we should stay up to date with the latest pharmacokinetic, safety, ethical, and legal profiles and regulations regarding synthetic peptide supplementation for injury recovery and sports performance optimization in our patients, from elite athletes to fitness fanatics, because they will continue to seek the latest and greatest in treatment options and will be approaching us with questions on their results, risks, and benefits.

Youth and Adolescent Athlete Musculoskeletal Health: Dietary and Nutritional Strategies to Optimise Injury Prevention and Support Recovery

Background: Despite the well-documented benefits of exercise and sports participation, young athletes are particularly vulnerable to musculoskeletal injuries. This is especially true during periods of rapid growth, sports specialisation, and high training loads. While injuries are an inevitable aspect of sports participation, the risk can be minimised by promoting the development of strong, resilient tissues through proper nutrition and injury prevention strategies. Moreover, targeted nutrition strategies can accelerate recovery and rehabilitation, allowing for a quicker return to sports participation. Methods: This narrative review synthesises scientific evidence with practical insights to offer comprehensive dietary recommendations aimed at strengthening tissues and supporting the healing process during recovery and rehabilitation. The selection of all sources cited and synthesised in this narrative review were agreed upon by contributing author consensus, experts in sports nutrition (R.A., H.V., B.D.) and exercise and sports medicine (M.H.). Results: Key topics include factors that contribute to injury susceptibility, general dietary recommendations for growth and development, sports nutrition guidelines, and nutrition considerations during injury and rehabilitation. This review also addresses external factors that may lead to suboptimal nutrition, such as food literacy and eating disorders. Conclusions: By highlighting these factors, this article aims to equip coaches, nutritionists, dietitians, athletic trainers, physical therapists, parents/guardians, sporting organisations, and schools with essential knowledge to implement effective nutritional strategies for injury prevention, recovery, and rehabilitation, ultimately enhancing long-term health and athletic performance.

Impact of Collagen Peptide Supplementation in Combination with Long-Term Physical Training on Strength, Musculotendinous Remodeling, Functional Recovery, and Body Composition in Healthy Adults: A Systematic Review with Meta-analysis

INTRODUCTION

Over the past decade, collagen peptide (CP) supplements have received considerable attention in sports nutrition research. These supplements have shown promising results in improving personal health, enhancing athletic performance, and preventing injuries in some but not all studies.

OBJECTIVE

A systematic review and meta-analysis of randomized controlled trials (RCTs) has been conducted to investigate the effects of long-term daily collagen peptide (CP) supplementation on strength, musculotendinous adaptation, functional recovery, and body composition in healthy adults, both with and without concurrent exercise interventions over several weeks.

METHODS

The PRISMA with PERSiST guidelines were followed for this systematic literature review, which was conducted in December 2023 using PubMed, Scopus, CINAHL, and SPORTDiscus databases. Eligible studies included healthy, normal to overweight adults over 17 years of age who engaged in exercise and daily collagen peptide (CP) supplementation for a minimum of 8 weeks (except one 3-week trial only included for maximal strength). Studies examining recovery-related outcomes were also eligible if they included a 1-week supplementation period without exercise. Methodological study quality was assessed using the PEDro scale. A random-effects model with standardized mean differences (SMD) of change scores was chosen to calculate overall effect sizes.

RESULTS

Nineteen studies comprising 768 participants were included in both the systematic review and meta-analysis. Results indicate statistically significant effects in favor of long-term CP intake regarding fat-free mass (FFM) (SMD 0.48, p < 0.01), tendon morphology (SMD 0.67, p < 0.01), muscle architecture (SMD 0.39, p < 0.01), maximal strength (SMD 0.19, p < 0.01), and 48 h recovery in reactive strength following exercise-induced muscle damage (SMD 0.43, p = 0.045). The GRADE approach revealed a moderate certainty of evidence for body composition, a very low certainty for tendon morphology and mechanical properties, and a low certainty for the remaining.

CONCLUSION

This systematic review and meta-analysis represents the first comprehensive investigation into the effects of long-term CP supplementation combined with regular physical training on various aspects of musculoskeletal health in adults. The findings indicate significant, though of low to moderate certainty, evidence of improvements in fat-free mass (FFM), tendon morphology, muscle mass, maximal strength, and recovery in reactive strength following exercise-induced muscle damage. However, further research is required to fully understand the mechanisms underlying these effects, particularly regarding tendon mechanical properties and short-term adaptations to collagen peptide (CP) intake without exercise, as observed in recovery outcomes. Overall, CP supplementation appears promising as a beneficial adjunct to physical training for enhancing musculoskeletal performance in adults. Open Science Framework (Registration DOI: https://doi.org/10.17605/OSF.IO/WCF4Y ).

The Effects of Collagen Peptides as a Dietary Supplement on Muscle Damage Recovery and Fatigue Responses: An Integrative Review

BACKGROUND/OBJECTIVES

The oral administration of hydrolyzed collagen peptides is a scientifically validated intervention for enhancing skeletal muscle health and performance. This integrative review consolidates the evidence supporting the use of low molecular weight collagen peptides (2000-3500 daltons) for their superior bioavailability and absorption. Our objective was to review the effects of collagen peptide or hydrolyzed collagen supplementation on muscle damage, recovery, and construction related to physical exercise.

METHODS

A bibliographic search was conducted in major English-language databases, including PubMed/Medline, using terms like "Peptides Collagen and Damage" and "collagen peptides AND Soreness Muscle". This review followed PRISMA guidelines, with bias risk assessed via the PEDro scale. The inclusion criteria were (a) randomized clinical trials, (b) randomized studies in humans with a control or placebo group, (c) studies assessing muscle damage or delayed onset muscle soreness via physiological markers or strength performance tests, and (d) studies using hydrolyzed collagen or collagen peptides.

RESULTS

Initially, 752 articles were identified. After applying the inclusion and exclusion criteria, including duplicate removal, eight articles with 286 participants were included. Of these, 130 participants received collagen peptide supplementation, while 171 received a placebo or control.

CONCLUSION

This integrative review supports the potential of collagen peptide supplementation to mitigate muscle stress from acute strenuous resistance training. However, due to the methodological heterogeneity among the studies, further clinical trials are needed to clarify the mechanisms underlying muscle improvement with collagen supplementation.

Protein Supplement Tolerability and Patient Satisfaction after Bariatric Surgery

PURPOSE

Disproportional fat-free mass loss often occurs post-bariatric surgery, partly due to insufficient protein intake during the post-surgery recovery phase. We compared five protein-enhancing strategies (PES) on patient tolerability, satisfaction and protein intake.

MATERIALS AND METHODS

Ninety-four participants, scheduled for bariatric surgery, were enrolled and allocated to either of the following: (1) whey powder, (2) hydrolysed collagen powder, (3) plant-based powder, (4) protein-rich products, (5) protein gel, or control. PES groups were instructed to add 30 g of powder or 2 gels or protein products to their diet. Patient satisfaction and tolerability were evaluated with questionnaires. Dietary intake was assessed prior to and during PES use.

RESULTS

Seven patients dropped out (i.e. loss of contact, personal reasons or post-surgery complications) yielding an analytical cohort of 87 participants. The majority of patients (61%) did not experience dietary complaints from PES and could use PES ≥ 5 days of the week. PES non-usage was mainly related to taste dislike (58%). Hydrolysed collagen scored highest on tolerability and satisfaction: 86% of the participants could use HC ≥ 5 days and 71% were satisfied with the product. PES increased protein intake from 54.7 ± 21.5 g/day to 64.7 ± 23.4 g/day during the intervention (p = 0.002), which differed from the control group (+ 10.1 ± 24.5 g/day vs. - 6.3 ± 23.8 g/day for controls, p = 0.019). Whey showed the highest increase, namely + 18.3 ± 16.3 g/day (p = 0.009).

CONCLUSION

PES were tolerated by the majority of participants, and an improved protein intake with PES use was seen. However, the taste of the products could be improved to further enhance satisfaction and tolerability.

Comprehensive review on collagen extraction from food by-products and waste as a value-added material

The consumption of animal products has witnessed a significant increase over the years, leading to a growing need for industries to adopt strict waste control measures to mitigate environmental impacts. The disposal of animal waste in landfill can result in diverse and potentially hazardous decomposition by-products. Animal by-products, derived from meat, poultry, seafood and fish industries, offer a substantial raw material source for collagen and gelatin production due to their high protein content. Collagen, being a major protein component of animal tissues, represents an abundant resource that finds application in various chemical and material industries. The demand for collagen-based products continues to grow, yet the availability of primary material remains limited and insufficient to meet projected needs. Consequently, repurposing waste materials that contain collagen provides an opportunity to meet this need while at the same time minimizing the amount of waste that is dumped. This review examines the potential to extract value from the collagen content present in animal-derived waste and by-products. It provides a systematic evaluation of different species groups and discusses various approaches for processing and fabricating repurposed collagen. This review specifically focuses on collagen-based research, encompassing an examination of its physical and chemical properties, as well as the potential for chemical modifications. We have detailed how the research and knowledge built on collagen structure and function will drive the new initiatives that will lead to the development of new products and opportunities in the future. Additionally, it highlights emerging approaches for extracting high-quality protein from waste and discusses efforts to fabricate collagen-based materials leading to the development of new and original products within the chemical, biomedical and physical science-based industries.

Dietary Collagen Peptides Ameliorate the Mood Status of Fatigue and Vigor: A Randomized, Double-Blinded, Placebo-Controlled, Parallel-Group Comparative Trial

The mood status of fatigue can impact daily activities. Dietary collagen peptides have been reported to be beneficial for health conditions. A randomized, double-blinded, placebo-controlled, parallel-group study investigated the effects of collagen peptides on mood status including fatigue, physical condition, and immunological status. The participants who were healthy but easily fatigued consumed active food containing collagen peptides (10 g/day) (n = 33) or placebo food (n = 33) for eight weeks. POMS® 2 was used to assess the perceived fatigue and other mood status. The primary outcome was the T-scores of Fatigue-Inertias at eight weeks. In addition, their physical condition and immunological parameters were evaluated. The data set was a per protocol set of 31 participants each in both groups. As for POMS® 2, the T-score of Fatigue-Inertias at eight weeks was significantly lower in the active group than in the placebo group (47.0 ± 7.4 versus 51.5 ± 9.0, p = 0.045). The T-score of Vigor-Activity was significantly higher in the active group than in the placebo group after eight weeks (53.9 ± 10.7 versus 47.3 ± 9.6, p = 0.002). Regarding the questionnaire on the physical condition, the Likert scale score on fatigue after a night's sleep at eight weeks was significantly lower in the active group than in the placebo group (median; 3.0 versus 4.0, p = 0.038). There were no significant differences in the measured values of immunological parameters. No safety-related issues were reported in this trial. The intake of collagen peptides (10 g/day) for eight weeks ameliorated the mood status of fatigue and vigor and increased the feeling of sleep restfulness. Dietary collagen peptides were efficient and safe nutritional ingredients for healthy but easily fatigued individuals.Clinical trial registry number and website: UMIN-CTR, UMIN000042291 https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000048280.

Local and Systemic Peptide Therapies for Soft Tissue Regeneration: A Narrative Review

Background: The musculoskeletal system, due to inherent structure and function, lends itself to contributing toward joint pain, whether from inflammatory disorders such as rheumatoid arthritis, degenerative diseases such as osteoarthritis, or trauma causing soft tissue injury. Administration of peptides for treatment of joint pain or inflammation is an emerging line of therapy that seeks to offer therapeutic benefits while remaining safe and relatively non-invasive. Purpose: The purpose of this study is to review the current literature on existing oral peptide agents, intra-articular peptide agents, and new developments in human trials to assess route of administration (RoA) for drug delivery in terms of soft tissue regeneration. Study Design: Narrative Review. Methods: A comprehensive literature search was conducted using the PubMed database. The search included medical subject headings (MeSH) terms related to peptide therapy, soft tissue regeneration, and RoA. Inclusion criteria comprised articles focusing on the mechanisms of action of peptides, clinical or biochemical outcomes, and review articles. Exclusion criteria included insufficient literature or studies not meeting the set evidence level. Conclusion: The review identified various peptides demonstrating efficacy in soft tissue repair. Oral and intra-articular peptides showed distinct advantages in soft tissue regeneration, with intra-articular routes providing localized effects and oral routes offering systemic benefits. However, both routes have limitations in bioavailability and absorption. Still in their infancy, further inquiries/research into the properties and efficacy of emerging peptides will be necessary before widespread use. As a viable alternative prior to surgical intervention, peptide treatments present as promising candidates for positive outcomes in soft tissue regeneration.

Relative Energy Deficiency in Sport (REDs) and knee injuries: current concepts for female athletes

In athletes, a mismatch between caloric intake and energy expended in exercise can eventually lead to Relative Energy Deficiency in Sport (REDs), where the athlete suffers from physiological derangements and decreased sport performance. The prevalence of REDs is higher in females than males. Females are already at a higher risk of knee injuries, which has been attributed to a multitude of factors such as hormonal influences, differences in musculoskeletal anatomy and neuromuscular control compared to males. The literature demonstrates an even higher risk of knee injuries in female athletes with symptoms of REDs. We propose the various factors that influence this risk. A reduction in anabolic hormones can affect muscle development and tendon repair. A relationship between poor neuromuscular control and knee injury has been established, and this can be further worsened in patients with menstrual dysfunction. Chronic deficiency in nutrients such as collagen and vitamin D can result in poorer recovery from microtrauma in tendons and ligaments. All these factors may contribute to increasing the risk of knee injuries, which may include anterior cruciate ligament tears, patella tendinopathy and patellofemoral pain syndrome. This review aims to educate sports clinicians to have a high index of suspicion when treating knee injuries in females; to screen and then manage for REDs if present, for holistic patient care.

Anti-Inflammatory and Antioxidant Properties of a New Mixture of Vitamin C, Collagen Peptides, Resveratrol, and Astaxanthin in Tenocytes: Molecular Basis for Future Applications in Tendinopathies

Tendinopathy is one of the most frequent musculoskeletal disorders characterized by sustained tissue inflammation and oxidative stress, accompanied by extracellular matrix remodeling. Patients suffering from this pathology frequently experience pain, swelling, stiffness, and muscle weakness. Current pharmacological interventions are based on nonsteroidal anti-inflammatory drugs; however, the effectiveness of these strategies remains ambiguous. Accumulating evidence supports that oral supplementation of natural compounds can provide preventive, and possibly curative, effects. Vitamin C (Vit C), collagen peptides (Coll), resveratrol (Res), and astaxanthin (Asx) were reported to be endowed with potential beneficial effects based on their anti-inflammatory and antioxidant activities. Here, we analyzed the efficacy of a novel combination of these compounds (Mix) in counteracting proinflammatory (IL-1β) and prooxidant (H2O2) stimuli in human tenocytes. We demonstrated that Mix significantly impairs IL-6-induced IL-1β secretion, NF-κB nuclear translocation, and MMP-2 production; notably, a synergistic effect of Mix over the single compounds could be observed. Moreover, Mix was able to significantly counteract H2O2-triggered ROS production. Together, these results point out that Mix, a novel combination of Vit C, Coll, Resv, and Asx, significantly impairs proinflammatory and prooxidant stimuli in tenocytes, mechanisms that contribute to the onset of tendinopathies.

Collagen hydrogel protects intestinal epithelial cells from indomethacin-induced damage: results of an in vitro experiment

INTRODUCTION. Indomethacin is a derivative of indoleacetic acid and has anti-inflammatory, analgesic and antipyretic effects. However, the results of numerous studies show that indomethacin, like many other nonsteroidal anti-inflammatory drugs (NSAIDs), have an inhibitory effect on the viability and functional activity of enterocytes. In this regard, the search for new ways to reduce the severity of side effects from the use of NSAIDs remains relevant. One of these approaches may be to enrich patients’ diets with non-drug biologically active compounds, including proteins. However, the effect of dietary proteins and biologically active peptides on NSAID-induced damage to the wall of the small intestine and stomach has not been sufficiently studied. AIM. To evaluate the ability of a collagen-containing dietary supplement to protect human duodenal epithelial cells (HuTu-80 line) from indomethacin-induced damage. MATERIALS AND METHODS. The composite collagen-containing hydrogel was provided by «FIRST ALIVE COLLAGEN» LLC (Russia) and is a registered dietary supplement. The work used a commercial culture of human skin fibroblast cells and human duodenal epithelial cells (line HuTu-80). The viability of intestinal cells and fibroblasts was assessed using light and fluorescence microscopy and flow cytometry methods. RESULTS AND DISCUSSION. It has been established that indomethacin inhibits cell growth, causes apoptosis and death of enterocytes, and also leads to the accumulation of cells in the S-phase, which indicates a disruption in the regulation of the cell cycle. It was revealed that collagen hydrogel prevents cell death caused by indomethacin and reduces the number of apoptotic cells in the population. The protective effect of collagen hydrogel is characterized by normalization of the cell cycle of enterocytes and restoration of their growth and proliferative activity. CONCLUSION. Thus, collagen hydrogel, in vitro, is able to reduce the pathogenic effect of indomethacin on human intestinal epithelial cells. The protective effect of collagen hydrogel is characterized by maintaining viability, inhibiting apoptotic processes, and maintaining cell cycle stability. The results obtained indicate the prospects of using a dietary supplement based on a composite collagen hydrogel as a prophylactic agent to reduce the risk of NSAID-associated gastrointestinal diseases. However, to confirm the therapeutic effectiveness of the dietary supplement, further research is necessary, both using experimental animal modeling of NSAID-associated diseases of the human gastrointestinal tract, and clinical studies.

Reduction in systemic muscle stress markers after exercise-induced muscle damage following concurrent training and supplementation with specific collagen peptides - a randomized controlled trial

Introduction

Collagen peptide supplementation in conjunction with exercise has been shown to improve structural and functional adaptations of both muscles and the extracellular matrix. This study aimed to explore whether specific collagen peptide (SCP) supplementation combined with a concurrent training intervention can improve muscular stress after exercise-induced muscle damage, verified by reliable blood markers.

Methods

55 sedentary to moderately active males participating in a concurrent training (CT) intervention (3x/week) for 12 weeks were administered either 15 g of SCP or placebo (PLA) daily. Before (T1) and after the intervention (T2), 150 muscle-damaging drop jumps were performed. Blood samples were collected to measure creatine kinase (CK), lactate dehydrogenase (LDH), myoglobin (MYO) and high-sensitivity C-reactive protein (hsCRP) before, after, and at 2 h, 24 h and 48 h post exercise.

Results

A combination of concurrent training and SCP administration showed statistically significant interaction effects, implying a lower increase in the area under the curve (AUC) of MYO (p = 0.004, ηp2 = 0.184), CK (p = 0.01, ηp2 = 0.145) and LDH (p = 0.016, ηp2 = 0.133) in the SCP group. On closer examination, the absolute mean differences (ΔAUCs) showed statistical significance in MYO (p = 0.017, d = 0.771), CK (p = 0.039, d = 0.633) and LDH (p = 0.016, d = 0.764) by SCP supplementation.

Conclusion

In conclusion, 12 weeks of 15 g SCP supplementation combined with CT intervention reduced acute markers of exercise-induced muscle damage and improved post-exercise regenerative capacity, as evidenced by the altered post-exercise time course. The current findings indicate that SCP supplementation had a positive effect on the early phase of muscular recovery by either improving the structural integrity of the muscle and extracellular matrix during the training period or by accelerating membrane and cytoskeletal protein repair.

Clinical trial registration

https://www.clinicaltrials.gov/study/NCT05220371?cond=NCT05220371&rank=1, NCT05220371.

AagingBase: a comprehensive database of anti-aging peptides

The process of aging is an intrinsic and inevitable aspect of life that impacts every living organism. As biotechnological advancements continue to shape our understanding of medicine, peptide therapeutics have emerged as a promising strategy for anti-aging interventions. This is primarily due to their favorable attributes, such as low immunogenicity and cost-effective production. Peptide-based treatments have garnered widespread acceptance and interest in aging research, particularly in the context of age-related therapies. To effectively develop anti-aging treatments, a comprehensive understanding of the physicochemical characteristics of anti-aging peptides is essential. Factors such as amino acid composition, instability index, hydrophobic areas and other relevant properties significantly determine their efficacy as potential therapeutic agents. Consequently, the creation of 'AagingBase', a comprehensive database for anti-aging peptides, aims to facilitate research on aging by leveraging the potential of peptide therapies. AagingBase houses experimentally validated 282 anti-aging peptides collected from 54 research articles and 236 patents. Employing state-of-the-art computational techniques, the acquired sequences have undergone rigorous physicochemical calculations. Furthermore, AagingBase presents users with various informative analyses highlighting atomic compositions, secondary structure fractions, tertiary structure, amino acid compositions and frequencies. The database also offers advanced search and filtering options and similarity search, thereby aiding researchers in understanding their biological functions. Hence, the database enables efficient identification and prioritization of potential peptide candidates in geriatric medicine and holds immense potential for advancing geriatric medicine research and innovations. AagingBase can be accessed without any restriction. Database URL: https://project.iith.ac.in/cgntlab/aagingbase/.

Assessing Impact of Cooking Methods on the Physicochemical and Sensory Properties of Instant Fortified Rice Congee for the Elderly

Instant rice congee (IRC) fortified with functional ingredients is designed for supplementation in nourishing the elderly. In this study, collagen peptide and curcumin were fortified in IRC to improve antioxidant and protein content. Different cooking methods were used to prepare rice congee in order to retain the nutritional content of instant fortified rice congee (IFRC). The effect of cooking methods on IFRC were investigated in this study using field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). As for cooking methods, the steaming method (IFRC-S) exhibited the highest total phenolic content (TPC) at 36.13 ± 5.63 mg GAE/g sample; a ferric reducing antioxidant power (FRAP) value of 6.39 ± 0.24 mg TE/g sample and protein content at 52.20 ± 6.48%. There were no significant differences (p > 0.05) in the texture analysis of hardness, cohesiveness and viscosity between the different cooking methods. However, the boiling method (IFRC-B) showed the highest adhesiveness, at -58.78 ± 11.55 g/s. IFRC with different cooking methods also had no significant differences (p > 0.05) in bulk density, volume expansion and the water absorption index. In sensory analysis, it was found that there were no significant differences (p > 0.05) detected in attribute colour, odour, taste, texture and overall acceptability between each cooking method. This study is particularly useful for gaining a preliminary understanding of the development of IRC focused on the elderly.

Does Chronic Pancreatitis in Growing Pigs Lead to Articular Cartilage Degradation and Alterations in Subchondral Bone?

Chronic pancreatitis (CP), a progressive inflammatory disease, poses diagnostic challenges due to its initially asymptomatic nature. While CP's impact on exocrine and endocrine functions is well-recognized, its potential influence on other body systems, particularly in young individuals, remains underexplored. This study investigates the hypothesis that CP in growing pigs leads to alterations in articular cartilage and subchondral bone, potentially contributing to osteoarthritis (OA) development. Utilizing a pig model of cerulein-induced CP, we examined the structural and compositional changes in subchondral bone, articular cartilage, and synovial fluid. Histological analyses, including Picrosirius Red and Safranin-O staining, were employed alongside immuno-histochemistry and Western blotting techniques. Our findings reveal significant changes in the subchondral bone, including reduced bone volume and alterations in collagen fiber composition. Articular cartilage in CP pigs exhibited decreased proteoglycan content and alterations in key proteins such as MMP-13 and TGF-β1, indicative of early cartilage degradation. These changes suggest a link between CP and musculoskeletal alterations, underscoring the need for further research into CP's systemic effects. Our study provides foundational insights into the relationship between CP and skeletal health, potentially guiding future pediatric healthcare strategies for early CP diagnosis and management.

Study of whey protein on muscle mass and functional rehabilitation in postoperative total knee arthroplasty patients

BACKGROUND

Patients who underwent total knee arthroplasty (TKA) often experience muscle loss due to pain and limited mobility. Nutritional supplementation and rehabilitation may positively affect the decline in muscle function.

OBJECTIVE

The purpose of this study is to evaluate whether whey protein intervention, in addition to conventional rehabilitation training, is beneficial in improving muscle function and quality of life in patients after TKA.

METHODS

72 patients who met the criteria were selected for this randomized controlled study. For the experimental group, whey protein was used as a daily supplement for 12 weeks, while the control group was given a placebo, during which both groups received conventional rehabilitation training. Muscle strength and each of the secondary observables needed to be measured and statistically analyzed preoperatively and at 4, 8, and 12 weeks post-intervention.

RESULTS

In total, 62 subjects completed the study: 32 in the experimental group and 30 in the control group. Both groups showed significant improvement in muscle strength, VAS, ROM, AKS and leg circumference after 12 weeks of treatment. Compared to the control group, patients in the experimental group showed significant improvement in muscle strength, VAS, ROM, AKS and leg circumference (p= 0.001, p= 0.002, p= 0.001, p= 0.001, p= 0.001, respectively) after 12 weeks of treatment.

CONCLUSION

The 12-week intervention of whey protein nutritional supplement showed significant improvement in muscle mass and function among post-TKA patients besides aiding with conventional rehabilitation exercise.

Effects of Specific Bioactive Collagen Peptides in Combination with Concurrent Training on Running Performance and Indicators of Endurance Capacity in Men: A Randomized Controlled Trial

BACKGROUND

First evidence indicates that the supplementation of specific collagen peptides (SCP) is associated with a significant improvement in running performance in physically active women; however, it is unclear if the same is true in males. The purpose of the present study was to investigate the effects of a concurrent training program including 60 min of continuous moderate intensity running training and 15 min of dynamic resistance training combined with supplementation of SCP on parameters of running performance in moderately trained males.

METHODS

In a double-blind, placebo-controlled, randomized trial, participants performed a 12 weeks concurrent training and ingested 15 g of SCP [treatment group (TG)] or placebo [control group (CG)] daily. Before and after the intervention, running endurance performance was measured by a 1-h time trial on a running track. Velocity at the lactate threshold (VLT) and at the individual anaerobic threshold (VIAT) were assessed on a treadmill ergometer. Body composition was evaluated by bioelectrical impedance analysis.

RESULTS

Thirty-two men (28.4 ± 5.2 years) completed the study and were included in the analysis. After 12 weeks, TG had a statistically significant (p ≤ 0.05) higher increase in running distance (1727 ± 705 m) compared to the CG (1018 ± 976 m) in the time trial. VLT increased in the TG by 0.680 ± 1.27 km h-1 and slightly decreased by - 0.135 ± 0.978 km h-1 in the CG, resulting in statistically significant group differences (p ≤ 0.05). A significantly higher improvement in VIAT (p ≤ 0.05) was shown in the TG compared with the CG only (1.660 ± 1.022 km h-1 vs 0.606 ± 0.974 km h-1; p ≤ 0.01). Fat mass decreased (TG - 1.7 ± 1.6 kg; CG - 1.2 ± 2.0 kg) and fat free mass increased (TG 0.2 ± 1.2 kg; CG 0.5 ± 1.3 kg) in both groups with no significant group differences.

CONCLUSION

In summary, supplementation with 15 g of SCP improved running performance in a 1-h time trial and enhanced indicators of endurance capacity at submaximal exercise intensities such as an increased velocity at the lactate as well as the anaerobic threshold more effectively than CT alone.

TRIAL REGISTRATION

ETK: 123/17; DRKS-ID: DRKS00015529 (Registered 07 November 2018-Retrospectively registered); https://drks.de/search/de/trial/DRKS00015529.

Evidence-based nutritional approaches to enhance exercise adaptations

PURPOSE OF REVIEW

The purpose of this opinion paper is to provide current-day and evidence-based information regarding dietary supplements that support resistance training adaptations or acutely enhance strength-power or endurance performance.

RECENT FINDINGS

Several independent lines of evidence support that higher protein diets, which can be readily achieved through animal-based protein supplements, optimize muscle mass during periods of resistance training, and this likely facilitates strength increases. Creatine monohydrate supplementation and peri-exercise caffeine consumption also enhance strength and power through distinct mechanisms. Supplements that favorably affect aspects of endurance performance include peri-exercise caffeine, nitrate-containing supplements (e.g., beet root juice), and sodium bicarbonate consumption. Further, beta-alanine supplementation can enhance high-intensity endurance exercise efforts.

SUMMARY

Select dietary supplements can enhance strength and endurance outcomes, and take-home recommendations will be provided for athletes and practitioners aiming to adopt these strategies.

Nitric Oxide as a Determinant of Human Longevity and Health Span

The master molecular regulators and mechanisms determining longevity and health span include nitric oxide (NO) and superoxide anion radicals (SOR). L-arginine, the NO synthase (NOS) substrate, can restore a healthy ratio between the dangerous SOR and the protective NO radical to promote healthy aging. Antioxidant supplementation orchestrates protection against oxidative stress and damage-L-arginine and antioxidants such as vitamin C increase NO production and bioavailability. Uncoupling of NO generation with the appearance of SOR can be induced by asymmetric dimethylarginine (ADMA). L-arginine can displace ADMA from the site of NO formation if sufficient amounts of the amino acid are available. Antioxidants such as ascorbic acids can scavenge SOR and increase the bioavailability of NO. The topics of this review are the complex interactions of antioxidant agents with L-arginine, which determine NO bioactivity and protection against age-related degeneration.

Analgesic efficacy of collagen peptide in knee osteoarthritis: a meta-analysis of randomized controlled trials

BACKGROUND

The management of knee osteoarthritis involves various treatment strategies. It is important to explore alternative therapies that are both safe and effective. Collagen peptides have emerged as a potential intervention for knee osteoarthritis. This study aims to evaluate the analgesic effects and safety of collagen peptide in patients diagnosed with knee osteoarthritis.

METHODS

We conducted a systematic literature search following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Multiple databases including PubMed, Scopus, EMBASE, Web of Science, Cochrane, and ClinicalTrials.gov were searched for randomized controlled trials (RCTs) published up to 27 May 2023 that focused on the analgesic outcomes and adverse events associated with collagen peptides or hydrolyzed collagen in patients with osteoarthritis. We assessed the quality of the included studies and the strength of evidence using the Cochrane ROB 2.0 tool and Grading of Recommendations, Assessment, Development, and Evaluations.

RESULTS

Four trials involving 507 patients with knee osteoarthritis were included and analyzed using the random-effects model. All these trials were considered to have a high risk of bias. Our results revealed a significant difference in pain relief between the collagen peptide group and the placebo group in patients with knee osteoarthritis (standardized mean difference: - 0.58; 95% CI - 0.98, - 0.18, p = 0.004; I2: 68%; quality of evidence: moderate). However, there was no significant difference in the risk of adverse events between collagen peptide and placebo (odds ratio: 1.66; 95% CI 0.99, 2.78, p = 0.05; I2: 0%; quality of evidence: very low).

CONCLUSIONS

Our findings demonstrate significant pain relief in patients with knee osteoarthritis who received collagen peptides compared to those who received placebo. In addition, the risk of adverse events did not differ significantly between the collagen peptide group and the placebo group. However, due to potential biases and limitations, well-designed randomized controlled trials are needed to validate and confirm these findings.

Effects of High-Intensity, Eccentric-Only Muscle Actions on Serum Biomarkers of Collagen Degradation and Synthesis

ABSTRACT

Neltner, TJ, Sahoo, PK, Smith, RW, Anders, JPV, Arnett, JE, Ortega, DG, Schmidt, RJ, Johnson, GO, Natarajan, SK, and Housh, TJ. Effects of high-intensity, eccentric-only muscle actions on serum biomarkers of collagen degradation and synthesis. J Strength Cond Res 37(9): 1729-1737, 2023-The purpose of this study was to examine the effects of high-intensity, eccentric-only muscle actions of the leg extensors on (a) serum biomarkers of collagen degradation (hydroxyproline [HYP] and C-terminal telopeptide of type I collagen [C1M]) and synthesis (pro-c1α1) and (b) the time course of changes in maximal voluntary isometric contraction (MVIC) and ratings of muscle soreness after the eccentric-only exercise bout. Twenty-five recreationally active men (mean ± SD: age = 21.2 ± 2.0 years) completed 5 sets of 10 bilateral, eccentric-only dynamic constant external resistance muscle actions of the leg extensors at a load of 110% of their concentric leg extension 1 repetition maximum. Analysis of variances (p < 0.05) and a priori planned pairwise comparisons using Bonferroni corrected (p < 0.0167) paired t tests were used to examine mean changes in blood biomarkers from baseline to 48 hours postexercise as well as in MVIC and soreness ratings immediately, 24 hours, and 48 hours postexercise. There were increases in HYP (3.41 ± 2.37 to 12.37 ± 8.11 μg·ml-1; p < 0.001) and C1M (2.50 ± 1.05 to 5.64 ± 4.89 μg·L-1; p = 0.003) from preexercise to 48 hours postexercise, but no change in pro-c1α1. Maximal voluntary isometric contraction declined immediately after the exercise bout (450.44 ± 72.80 to 424.48 ± 66.67 N·m; p = 0.002) but recovered 24 hours later, whereas soreness was elevated immediately (6.56 ± 1.58; p < 0.001), 24 hours (3.52 ± 1.53; p < 0.001), and 48 hours (2.60 ± 1.32; p = 0.001) postexercise. The eccentric-only exercise bout induced increases in collagen degradation but had no effect on collagen synthesis. These findings provide information for clinicians to consider when prescribing exercise after an acute injury or surgery.

The collagen market and knowledge, attitudes, and practices of Brazilian consumers regarding collagen ingestion

Collagen is considered a nutraceutical, and its consumption has been expanding due to the increased life expectancy, rising per capita income, and increased consumer awareness of health care. This study aimed to evaluate consumers' perceptions, knowledge, attitudes, and practices about the consumption of collagen-based products by using an online questionnaire and to correlate them with socio-economic data. A market survey (pharmacy stores and online) was also conducted to evaluate the available products. In total, 275 participants answered the survey, 73.3% from the Southeast region, mostly female (84.0%). Most participants reported three months as the period of collagen intake (31.6%), and the consumption period was associated with the perception of the health benefits (p < 0.001). Furthermore, the participants' knowledge and perceptions regarding collagen intake are frequently associated with dermatological and orthopedic changes. Collagen-based products supplementation is a growing market with a broad target audience (genders, age groups, and socio-economic levels). The commercial presentation of collagen has been diversified over the years, and powder collagen is the most consumed (52.7%) and cheapest compared with capsules, pills, or gummies. The results of the present study demonstrate that most consumers of this type of supplement associate its benefits with aesthetic care such as skin, hair, and nails, although the scientific literature has shown its effects in treating osteoarticular diseases, for example. Undoubtedly, the correct dose prescription, treatment time, and choice of product presentation must be analyzed carefully, as they significantly impact treatment results.

Advances in nutritional supplementation for sarcopenia management

Sarcopenia is a syndrome characterized by a decline in muscular mass, strength, and function with advancing age. The risk of falls, fragility, hospitalization, and death is considerably increased in the senior population due to sarcopenia. Although there is no conclusive evidence for drug treatment, resistance training has been unanimously recognized as a first-line treatment for managing sarcopenia, and numerous studies have also pointed to the combination of nutritional supplementation and resistance training as a more effective intervention to improve quality of life for people with sarcopenia. People with both malnutrition and sarcopenia have a higher mortality rate, so identifying people at risk of malnutrition and intervening early is extremely important to avoid sarcopenia and its associated problems. This article provides important information for dietary interventions in sarcopenia by summarizing the discoveries and developments of nutritional supplements such as protein, leucine, β-hydroxy-β-methylbutyric acid, vitamin D, vitamin C, vitamin E, omega-3 fatty acids, creatine, inorganic nitrate, probiotics, minerals, collagen peptides, and polyphenols in the management of sarcopenia.

TFOS Lifestyle: Impact of nutrition on the ocular surface

Nutrients, required by human bodies to perform life-sustaining functions, are obtained from the diet. They are broadly classified into macronutrients (carbohydrates, lipids, and proteins), micronutrients (vitamins and minerals) and water. All nutrients serve as a source of energy, provide structural support to the body and/or regulate the chemical processes of the body. Food and drinks also consist of non-nutrients that may be beneficial (e.g., antioxidants) or harmful (e.g., dyes or preservatives added to processed foods) to the body and the ocular surface. There is also a complex interplay between systemic disorders and an individual's nutritional status. Changes in the gut microbiome may lead to alterations at the ocular surface. Poor nutrition may exacerbate select systemic conditions. Similarly, certain systemic conditions may affect the uptake, processing and distribution of nutrients by the body. These disorders may lead to deficiencies in micro- and macro-nutrients that are important in maintaining ocular surface health. Medications used to treat these conditions may also cause ocular surface changes. The prevalence of nutrition-related chronic diseases is climbing worldwide. This report sought to review the evidence supporting the impact of nutrition on the ocular surface, either directly or as a consequence of the chronic diseases that result. To address a key question, a systematic review investigated the effects of intentional food restriction on ocular surface health; of the 25 included studies, most investigated Ramadan fasting (56%), followed by bariatric surgery (16%), anorexia nervosa (16%), but none were judged to be of high quality, with no randomized-controlled trials.

Food-derived bioactive peptides as momentous food components: Can functional peptides passed through the PI3K/Akt/mTOR pathway and NF-κB pathway to repair and protect the skeletal muscle injury?

Muscle injury is defined as an overuse injury or traumatic distraction of a muscle, which is latent in any sport event, from amateur to large events. Based on previous numbers of muscle injuries and time spent to the athletes' recovery, the use of dietary functional factors intervention strategies is essential to enhance the recovery process and health. In recent years, there has been increasing evidence that biologically active peptides played an important role in sports nutrition and muscle injure recovery. Food-derived bioactive peptides were physiologically active peptides mostly derived from proteins following hydrolysis, which could be resorbed in intact form to reduce muscle damage following exercise and induce beneficial adaptions within the connective tissue. However, the complexity of the histoarchitectural considerations for skeletal muscle injuries and the repair mechanism of damaged skeletal muscle were not well known. In the following overview, the potential mechanisms and possible limitations regarding the damaged skeletal muscle metabolism were summarized, which aimed to present an overview of the nutritional strategies and recommendations after a muscular sports injury, emphasizing the use of main bioactive peptides. In addition, this review will provide implications for the studies of dietary bioactive peptides in the future.

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.

Development of a mobile application to monitor the effectiveness of a hydrolyzed cartilage matrix supplement on joint discomfort: a real-life study

BACKGROUND

Joint discomfort is a widespread and growing problem in active adults. The rising interest in preventative nutrition has increased the demand for supplements reducing joint discomfort. Protocols assessing the effect of a nutritional intervention on health commonly involve a series of face-to-face meetings between participants and study staff that can weigh on resources, participant availabilities and even increase drop-out rates. Digital tools are increasingly added to protocols to facilitate study conduct but fully digitally run studies are still scarce. With the increasing interest in real-life studies, the development of health applications for mobile devices to monitor study outcomes could be of great importance.

OBJECTIVE

The purpose of the current real-life study was to develop a specific mobile application, Ingredients for LifeTM, to conduct a 100% digital study testing the effectiveness of a hydrolyzed cartilage matrix (HCM) supplement on joint discomfort in a heterogeneous group of healthy, active consumers.

METHODS

The 'Ingredients for LifeTM ' mobile app using Visual Analog Scale (VAS) was specifically developed to monitor the variation in joint pain after exercise by the study participants. A total of 201 healthy and physically active, adult women and men (18 to 72 years old) with joint pain completed the study over a period of 16 weeks. Participants were randomly allocated to the study groups and did not receive any dietary or lifestyle advice. Each participant indicated one area of joint pain and logged the type and duration of their weekly activities. They received blinded study supplements and took a daily regimen of 1 g of hydrolyzed cartilage matrix (HCM-G) or 1g of maltodextrin (placebo group; P-G) for 12 weeks while weekly logging joint pain scores in the app. This was followed by a 4-week wash out period during which participants continued reporting their joint pain scores (until the end of week 16).

RESULTS

Joint pain was reduced within 3 weeks of taking a low dosage of HCM (1g/day), regardless of gender, age group and activity intensity when compared to the placebo-group. After stopping supplementation, joint pain scores gradually increased but still remained significantly lower than placebo after 4 weeks of washout. The low dropout rate (< 6% of participants, mainly in the P-G) demonstrates the digital study was well received by the study population.

CONCLUSIONS

The digital tool allowed to measure a heterogeneous group of active adults in a real-life setting (without any lifestyle intervention), thus promoting inclusivity and diversity. With low dropout rates, it demonstrates that mobile applications can generate qualitative, quantifiable, real-world data showcasing supplement effectiveness. The study confirmed that the oral intake of a low dose (1g/day) of HCM led to a significant reduction of joint pain from 3 weeks after starting supplementation.

CLINICALTRIAL

Nutritional Strategies in the Rehabilitation of Musculoskeletal Injuries in Athletes: A Systematic Integrative Review

It is estimated that three to five million sports injuries occur worldwide each year. The highest incidence is reported during competition periods with mainly affectation of the musculoskeletal tissue. For appropriate nutritional management and correct use of nutritional supplements, it is important to individualize based on clinical effects and know the adaptive response during the rehabilitation phase after a sports injury in athletes. Therefore, the aim of this PRISMA in Exercise, Rehabilitation, Sport Medicine and Sports Science PERSiST-based systematic integrative review was to perform an update on nutritional strategies during the rehabilitation phase of musculoskeletal injuries in elite athletes. After searching the following databases: PubMed/Medline, Scopus, PEDro, and Google Scholar, a total of 18 studies met the inclusion criteria (Price Index: 66.6%). The risk of bias assessment for randomized controlled trials was performed using the RoB 2.0 tool while review articles were evaluated using the AMSTAR 2.0 items. Based on the main findings of the selected studies, nutritional strategies that benefit the rehabilitation process in injured athletes include balanced energy intake, and a high-protein and carbohydrate-rich diet. Supportive supervision should be provided to avoid low energy availability. The potential of supplementation with collagen, creatine monohydrate, omega-3 (fish oils), and vitamin D requires further research although the effects are quite promising. It is worth noting the lack of clinical research in injured athletes and the higher number of reviews in the last 10 years. After analyzing the current quantitative and non-quantitative evidence, we encourage researchers to conduct further clinical research studies evaluating doses of the discussed nutrients during the rehabilitation process to confirm findings, but also follow international guidelines at the time to review scientific literature.

The effects of collagen peptides on exercise-induced gastrointestinal stress: a randomized, controlled trial

PURPOSE

We examined the effects of collagen peptides (CP) supplementation on exercise-induced gastrointestinal (GI) stress.

METHODS

In a randomized, crossover design, 20 volunteers (16 males: [Formula: see text]O_2max, 53.4 ± 5.9 ml·kg^-1) completed 3 trials: a non-exercise rest trial, with no supplement (REST) and then an exercise trial with CP (10 g·day^-1) or placebo control (CON) supplements, which were consumed for 7 days prior to, and 45 min before, a 70 min run at 70-90% of [Formula: see text]O_2max. Outcome measures included urinary lactulose and rhamnose (L/R), intestinal fatty acid binding protein (I-FABP), lipopolysaccharide (LPS), anti-LPS antibody, monocyte-chemoattractant protein-1 (MCP-1), interleukin (IL) 6 and 8, cortisol, alkaline phosphatase (ALP) (measured pre, 10 min post and 2 h post) and subjective GI symptoms.

RESULTS

There were no differences in heart rate, perceived exertion, thermal comfort, or core temperature during exercise in the CP and CON trials (all P > 0.05). I-FABP was higher in CP (2538 ± 1221 pg/ml) and CON (2541 ± 766 pg/ml) vs. REST 2 h post (1893 ± 1941 pg/ml) (both P < 0.05). LPS increased in CON vs. REST 2 h post (+ 71.8 pg/ml; P < 0.05). Anti-LPS antibody decreased in CON and CP vs. REST at post (both P < 0.05). There were no differences in MCP-1, IL-6, and IL-8 between the CP and CON trials (all P > 0.05), and no differences in L/R or GI symptoms between CON and CP (all P > 0.05).

CONCLUSION

Collagen peptides did not modify exercise-induced changes in inflammation, GI integrity or subjective GI symptoms but LPS was higher in CON 2 h post-exercise and thus future studies may be warranted.

Effects of 8 Weeks of Shilajit Supplementation on Serum Pro-c1α1, a Biomarker of Type 1 Collagen Synthesis: A Randomized Control Trial

Type 1 collagen is an abundant structural protein with importance to the skin, eyes, bones, ligaments, tendons, and muscles. Shilajit supplementation has been shown to increase gene expression of collagen synthesis, however, it is unclear if increased gene expression translates to increases in circulating levels. Therefore, the purpose of the present study was to examine the effects of 8 weeks of daily supplementation with 500 mg·d-1 and 1000 mg·d-1 of Shilajit versus placebo on serum pro-c1α1, a biomarker of type 1 collagen synthesis. Thirty-five recreationally trained men (mean ± SD: age = 21.1 ± 1.8 yrs; body mass = 80.7 ± 12.4 kg; height = 180.9 ± 6.7 cm) volunteered to participate in this study. Mixed factorial and one-way ANOVAs were used to analyze mean differences between groups, with follow-up t-tests when necessary. Individual subject responses were assessed using the minimal clinically important difference and Chi-squared tests. There were significant (Low dose: p = 0.008, d = 1.2; High dose: p = 0.007, d = 1.3) increases in serum pro-c1α1 from pre- (Low dose: 42.5 ± 12.4 ng·mL-1; High dose: 42.7 ± 12.7 ng·mL-1) to post-supplementation (Low dose: 82.3 ± 46.5 ng·mL-1; High dose: 113.1 ± 78.7 ng·mL-1) for the low and high dose groups, however, no change (p > 0.05) for the placebo group. A greater proportion (p = 0.03) of subjects exhibited increases in pro-c1α1 that exceeded the minimal clinically important difference in the high dose Shilajit group (75%) compared to the placebo group (30%), but no differences (p = 0.06) between the low dose Shilajit group (69%) and placebo. In conclusion, 8 weeks of Shilajit supplementation with 500 and 1000 mg·d-1 increased type 1 collagen synthesis as indicated by serum levels of pro-c1α1.

Characterization of Acid- and Pepsin-Soluble Collagen Extracted from the Skin of Purple-Spotted Bigeye Snapper

Fish processing waste is a prospective source of collagen and a cost-effective environmental pollutant. The skin of the purple-spotted bigeye snapper (Priacanthus tayenus) was extracted utilising various acid soluble collagens (ASC) including acetic acid (AAC), lactic acid (LAC), citric acid (CAC) and pepsin soluble collagens (PSC). In this study, PSC (6.65%) had the highest collagen yield, followed by AAC (5.79%), CAC (4.15%), and LAC (3.19%). The maximum temperatures (Tmax) denaturation of AAC, LAC, CAC, and PSC were 31.4, 31.7, 31.5, and 33.2 °C, respectively. UV-VIS absorption spectra showed all extracted collagens had a range of absorbance at 230 nm, due to the presence of glycine, proline, hydroxyproline, and triple-helical collagen. Additionally, they exhibited amide A, B, amide I, II, and III peaks. SDS−PAGE identified all extracted collagens as type I. The PSC had a significantly higher (p < 0.05) hydroxyproline content than acidic extraction 66.3 ± 1.03 (mg/g sample). Furthermore, all samples were extremely soluble in acetic conditions at pH 5, and all collagen was soluble in NaCl up to 3% (w/v). Therefore, PSC was the best treatment since it did not impact collagen triple helical and acetic acid yielded the most collagen in ASC extraction. Overall, the analysis revealed that fish skin waste might be used as an alternate source of collagen in diverse applications, particularly in food applications.

Sustainable Applications of Animal Waste Proteins

Currently, the growth of the global population leads to an increase in demand for agricultural products. Expanding the obtaining and consumption of food products results in a scale up in the amount of by-products formed, the development of processing methods for which is becoming an urgent task of modern science. Collagen and keratin make up a significant part of the animal origin protein waste, and the potential for their biotechnological application is almost inexhaustible. The specific fibrillar structure allows collagen and keratin to be in demand in bioengineering in various forms and formats, as a basis for obtaining hydrogels, nanoparticles and scaffolds for regenerative medicine and targeted drug delivery, films for the development of biodegradable packaging materials, etc. This review describes the variety of sustainable sources of collagen and keratin and the beneficial application multiformity of these proteins.