Effect of targeted intervention on C-terminal agrin fragment and its association with the components of sarcopenia: a scoping review

C-Terminal Agrin Fragment as a Biomarker for Sarcopenia: A Systematic Review and Meta-Analysis

BACKGROUND

Sarcopenia is a gradual decline in skeletal muscle mass and strength, which eventually leads to reduced physical performance. 50% of people aged 60-80 years suffer from sarcopenia. Considering the devastating outcomes and the importance of promoting healthy ageing, the diagnosis and prevention of sarcopenia is of utmost importance. Recently, C-terminal agrin fragment (CAF) has been identified as an indicator for early diagnosis of sarcopenia. So far, systematic reviews demonstrating CAF as a biomarker for sarcopenia have been conducted, but a meta-analysis is still needed. This study contains systematic review as well as detailed meta-analysis to better understand the association of CAF and sarcopenia.

METHODS

Articles were primarily obtained from four different databases. Studies demonstrating the association between CAF and sarcopenia were selected. Data extraction and analysis were performed using STATASE 16 software. The risk of bias and quality assessment of each study was carried out using Joanna Briggs Institute (JBI) Critical Appraisal Tool. Meta-regression, subgroup and sensitivity analysis were conducted to identify the source of heterogeneity.

RESULTS

Seventeen studies were included in the qualitative analysis, out of which 10 were included in the quantitative analysis. The meta-analysis showed that CAF levels were significantly higher in sarcopenia patients, with an effect size of 1.93 (ROM = 1.93, 95% CI [1.49 to 2.36]; p = 0.00) and 1.38 (ROM = 1.38, 95% CI [0.94 to 1.83], p = 0.00) when compared with non-sarcopenic and non-sarcopenic (other co-morbidities) group, respectively. CAF levels were also negatively associated with hand grip strength (HGS) and skeletal muscle index (SMI) with an effect size of 1.09 (ROM = 1.09 with 95% CI [1.05 to 1.13], p = 0.00) and 1.10 (ROM = 1.10 with 95% CI [1.05 to 1.14], p = 0.00), respectively. Meta-regression and subgroup analysis revealed that although sarcopenia is associated with increasing age, the correlation between CAF and age was statistically insignificant (p = 0.44), suggesting that the variation of age among sarcopenia patients could be source of heterogeneity among studies. All the studies included in the meta-analysis reported low risk of bias.

CONCLUSIONS

Our meta-analysis concluded that elevated CAF levels were associated with sarcopenia and decreased HGS and SMI. CAF could serve as a valuable marker for the early detection and monitoring of sarcopenia, ultimately facilitating the management and treatment of this debilitating condition.

Photobiomodulation therapy as an adjunct to resistance exercises on muscle metrics, functional balance, functional capacity, and physical performance among older adults: A systematic scoping review

This scoping review aims to summarize the literature on photobiomodulation (PBM) therapy as an adjunct to resistance exercise among older adults, focusing on its effects on muscle metrics, functional balance, capacity, and physical performance. The participants included were older adults aged ≥ 60 years and either gender. The concept was the application of PBM and resistance exercises with no limits on the context parameters. The databases Medline, Embase, Scopus and Web of Science were searched from inception till February 2024. Methodological quality was assessed using the Cochrane risk of bias 2.0. A total of 10 studies were included in the review. PBM, along with resistance training, was reported in six studies, whereas four reported PBM with isometric fatigue protocol. PBM with a wavelength of 808 nm was given on the belly of the rectus femoris muscle in most of the studies. The common dosimetry parameters used were- power density 35.7 W/cm2, energy density 250 J/cm2, 8 sites, energy per site 7 J, duration of 70 s per site, spot size per diode of 0.028 cm2, and stationary contact of application. The application of PBM therapy alongside resistance exercise has been found to improve muscle metrics, functional capacity, and functional performance and reduce fatigability when compared with the control group in most of the studies. When incorporating PBM therapy as an adjunct to resistance training, it is crucial to consider the dosimetry parameters involved-to achieve the intended therapeutic effect. Adjusting treatment parameters with this information can optimize the effectiveness of PBM therapy and improve treatment outcomes for patients.

Is sarcopenia a real concern in ankylosing spondylitis? A systematic literature review

PURPOSE

Sarcopenia is a condition defined as loss of muscle mass and strength, associated with poor functional performance and disability. Sarcopenia can be exacerbated or worsened in presence of inflammation, sedentary lifestyle and cytokine imbalance, thus it frequently occurs in people affected by rheumatic diseases. This systematic literature review aims to explore the association between sarcopenia and spondyloarthritis (SpA) and its most frequent manifestation, i.e. ankylosing spondylitis (AS).

METHODS

The Scopus, PubMed, and Web of Science databases were searched for articles on muscle mass, muscle strength and axial SpA, from any date to November 2023. Only studies written in English were considered. The methodological quality of the studies included in the review was evaluated using the Newcastle-Ottawa Scales for observational studies and for case-control studies.

RESULTS

190 papers were retrieved from the searches, 14 of which met the inclusion criteria. Rather than diagnosis of sarcopenia, pre-sarcopenia or probable sarcopenia were frequent in people with AS, with a great reduction especially of muscle strength. The pre-sarcopenia status appears to be related to high AS disease activity, suggesting that chronic inflammation resulting in pain, less movement and decreased physical activity could play a role in the muscle heath of AS patients.

CONCLUSIONS

Our review confirms the existence of an association between AS and loss of muscle strength-likely sarcopenia-already at a young age. Preventive and early strategies should be adopted to ensure successful aging for individuals with AS.

The effects of TRX suspension training on sarcopenic biomarkers and functional abilities in elderlies with sarcopenia: a controlled clinical trial

BACKGROUND

Sarcopenia is an age-related progressive loss of muscle mass and strength that can be modulated by resistance training. This study aimed to investigate the effects of TRX Suspension Training (TST) on serum levels of neuromuscular and growth factors and functional indices in elderly men with sarcopenia, an age-related condition characterized by progressive muscle mass and strength loss.

METHODS

Nineteen sarcopenic elderly men (age = 74.87 ± 4.58 years) were randomly assigned into two groups, the TST group (n = 10) and the control group (n = 9). Serum concentrations of regulatory muscle markers, anthropometric and body composition indices, and functional tests were evaluated at baseline and after 8 weeks. The training protocol consisted of eight weeks of TRX exercises, with three weekly sessions.

RESULTS

After 8 weeks of training, growth factors such as Follistatin (FST) (P = 0.001), 22 kDa C-terminal agrin fragment (CAF) (P = 0.031), and growth differentiation factor 15 (GDF15) (P = 0.049) increased significantly in the training group in comparison to the control group and Myostatin (MSTN) (P = 0.002) had a significant decrease. However, there was no significant difference in ASMM/m2 (P = 0.527), SMM/m2 (P = 0.621), or Body fat mass (P = 0.433) within or between groups. In addition, the TRX Suspension Training had a significant effect on the functional tests and improved gait speed (P = 0.037), chair stand (P = 0.016), and TUG (P = 0.016) as well as Handgrip strength (P = 0.035).

CONCLUSION

Our findings highlight the efficacy of TRX Suspension Training in enhancing the serum levels of muscle growth factors and functional capacities among elderly individuals with sarcopenia. Therefore, considering the ongoing COVID-19 pandemic, this protocol can prove beneficial for this demographic group.

TRIAL REGISTRY

Iranian Registry of Clinical Trials identifier: IRCT20230727058944N1, prospectively registered 20-09-2023, https://en.irct.ir/trial/71635.