Musculoskeletal injuries (MSK-I) are a collective term for damage to muscles, tendons, joints, ligaments, and soft tissues resulting in functional imbalance. MSK-I encompasses degenerative and inflammatory disorders that may involve the human body structure and provoke acute or chronic pain as well as decrease in mobility, which is one of the largest contributors to the global social burden, including healthcare expenditures, disability, and reduced quality of life (Walter et al., 2021). MSK-I can occur at any age, while obese children and adolescents, those suffering from mental disorders, a sedentary lifestyle, and regular physical activity, and smokers are at the highest risk. In adults, the risk factors for MSK-I include a sedentary lifestyle, obesity, and persistent pain as a result of previous injuries. Moreover, the growing tendency to a sedentary lifestyle in developing countries poses a major risk factor for the worldwide rise in MSK-I (Briggs et al., 2016).
MSK-I conditions may worsen in older individuals due to comorbidities and bone fragility. MSK-I is also one of the most common conditions among athletes, leading to consequences such as decreased performance, early retirement, and high treatment costs (Gimigliano et al., 2021). In the general population, a strong association has been identified between occupational factors and the worsening of musculoskeletal disorders (Soares et al., 2021). Additionally, aging represents the most common risk factor for sarcopenia, a condition characterized by the loss of skeletal muscle mass, which can result in the loss of independence in daily activities.
Current treatment modalities for MSK-I face several limitations that affect their effectiveness. Conventional therapeutic approaches such as physiotherapy, non-steroidal anti-inflammatory drugs (NSAIDs), and steroid injections typically provide only limited clinical benefit and may result in long-term functional impairments (Weiss et al., 2018).
Exosomes represent a class of single-membrane organelles that possess distinctive cell-like morphology and carry protein, lipid, and carbohydrate moieties (Pegtel & Gould, 2019). Exosomes participate in the regulation of the extracellular matrix homeostasis and have the ability to transfer signaling molecules to target cells, which contribute to their extensive clinical applications. Exosomes are considered a critical element of contemporary biomedical science that is currently being explored as a viable therapeutic avenue in a variety of disease paradigms (H. Huang et al., 2024). In the field of orthopedics, exosomes have demonstrated promising potential in the treatment of various musculoskeletal-related degenerative disorders (Jia et al., 2023; Y. Yue et al., 2024).
The association between physical activity and exosome secretion into the circulation, where they can exert communication-mediated effects on other tissues, was initially described by Frühbeis et al. (2015). An increasing number of studies have sought to elucidate the physiological relevance of exosome-mediated crosstalk between physically active individuals. The majority of studies utilized exosomes isolated from numerous sources; however, it is still unclear which particular origin possesses the most potent cargo of bioactive molecules involved in the regulation of musculoskeletal tissue homeostasis.
For instance, whereas exosomes originating from the muscle interstitial space demonstrated prominent expression of marker molecules, those isolated from the plasma showed barely detectable levels of several surface proteins (Frühbeis et al., 2015). This review is therefore urgently required to synthesize these fragmented preclinical findings and provide a much-needed consensus on standardized isolation protocols and administration routes. This study establishes a foundational framework for the effective translation of exercise-induced exosome therapies into clinical practice.
EXOSOMAL CARGO PROFILES AND BIOACTIVITY OUTCOMES
Exosome transfection from the control and treatment groups in vivo and in vivo showed differences in their effectiveness in promoting the osteogenesis process. Exosomes from the physical exercise group demonstrated stronger osteogenic capacity, indicating that their bioactivity is positively correlated with musculoskeletal function (Ma et al., 2023). To determine the bioactive content, the study by Ma et al. analyzed differences in differentially expressed proteins between exosomes from the control group and the physical exercise group.
The results showed that there were four proteins that had the most significant expression difference between the two models, namely lactate dehydrogenase A (LDHA), pyruvate kinase M (PKM), UTP–glucose-1-phosphate uridylyltransferase (UGP2), and beta-enolase (ENO3) (Ma et al., 2023). Gene Ontology (GO) enrichment analysis demonstrated the roles of these proteins in glycolytic processes, glucose metabolic processes, pyruvate metabolic processes, and lactate metabolic processes. These results indicate findings consistent with the observed effect of exosome transfection, which is underpinned by aerobic glycolysis as a key feature of osteoblast differentiation and contributing 80% of energy production in mature osteoblasts (Ma et al., 2023).
Exercise-induced exosomes significantly increased cell proliferation compared to control in in vitro assays (p < 0.0001) (Zhang et al., 2025). Additionally, exercise-induced exosomes have potential in osteogenic processes by promoting osteoblast differentiation. This is influenced by the increased expression of osteogenesis-related transcription factors in exercise-induced exosomes, such as Runx2, OCN, osteopontin, and type I collagen. The report emphasizes that exercise-induced exosomes have potential to facilitate musculoskeletal regeneration (Zhang et al., 2025). Further investigation of the bioactive molecular content of exercise-induced exosomes found that miR-206 showed the most significant upregulation (p < 0.05). Analysis of miR-206 target genes revealed its involvement in regulating osteoblast differentiation, ossification, and stem cell proliferation processes (Zhang et al., 2025). A study by de Mendonça et al. found a positive correlation in the concentrations of several specific miRNAs in models receiving physical exercise intervention independent of diet (de Mendonça et al., 2020). Observations in the exercise group model found correlations between the gastrocnemius muscle and miR-192 (p = 0.049), as well as miR-122 (p = 0.0369). In addition, miR-192 from the gastrocnemius muscle was negatively correlated with fat mass (p = 0.0268) in the context of physical exercise (de Mendonça et al., 2020). A study by Watanabe et al. conducted proteomic analysis to identify protein profiles contained in exosomes from the skeletal muscle interstitium model.
The results showed that, in addition to exosomal marker proteins (Alix, CD81, and Flotillin-1), they also contained skeletal muscle proteins, namely ATP2A1, β-enolase, calsequestrin 2, caveolin-3, and desmin. Furthermore, investigation of the myomiR profile of interstitial exosomes showed that miR-1, -206, -431, and -486, which are abundantly expressed in muscle, were concentrated in interstitial exosomes (Watanabe et al., 2022).
HISTOLOGICAL OUTCOMES
Of the four studies, only two studies reported histological observation results (Ma et al., 2023; Zhang et al., 2025). The study by Ma et al. conducted histological observations using micro-CT scanning to assess whether musculoskeletal injection of exercise-derived exosomes could protect mice from disuse osteoporosis. The results reported that after exosome injection every 3 days for 3 weeks, there was improvement in trabecular bone loss, increased bone volume fraction, trabecular number, cortical bone thickness, and connectivity density, and reduced trabecular separation (Ma et al., 2023). Histomorphometric analysis was also performed, showing an increased mineral apposition rate in the distal femur, and through immunofluorescence staining an increased number of cells expressing osteocalcin (OCN) and type I collagen (COL-1) was identified, which further validated the bone formation effect and represents an important bioactive factor in the interaction between bone and muscle metabolism (Ma et al., 2023).
The same scanning method was used in the study by Zhang et al., by performing micro-CT scanning of the femur in the physical exercise group. The results showed a significant increase in bone mass compared with control. The observations also specifically reported that physical exercise resulted in a marked increase in bone mineral density, bone volume, trabecular number, and trabecular thickness. In addition, a slight increase in cortical thickness and area was found after the physical exercise intervention. H&E staining revealed increased trabecular density under the epiphyseal plate accompanied by an increased trabecular area (p < 0.01). To evaluate the bone formation rate, calcium staining was performed, the result indicating a significant increase (p < 0.0001) of mineral apposition rate, bone formation per surface, and mineralizing surface per bone surface. In addition, Immunofluorescence staining results reported that the number of H-type blood vessels under the epiphyseal plate increased after physical exercise (Zhang et al., 2025).
MOLECULAR MECHANISMS
The preclinical evidence analyzed in this systematic review shows that the regenerative effects of exercise-induced exosomes are not mediated by a single type of molecule, but rather through a complex synergy between metabolic protein cargo and non-coding genetic material, particularly miRNAs. Exosomes from the physical exercise group were consistently enriched with bioactive content compared with exosomes from the control group, as seen from observations suggesting increased cell proliferation, osteoblast differentiation, and activation of osteogenic pathways. At the protein level, the study by Ma et al. has shown that exosomes derived from musculoskeletal tissue under the influence of physical exercise were enriched with proteins involved in energy metabolism, including LDHA, PKM, UGP2, and ENO3 (Ma et al., 2023). Considering that aerobic glycolysis supplies the majority of energy requirements in mature osteoblasts, the increased presence of metabolic proteins in exercise-induced exosomes indicates their function in directly supporting osteogenesis (Lee et al., 2017).
In addition to protein cargo, genetic material in the form of miRNAs plays an important role in regulating target cell responses. This finding has been supported by previous studies reporting that among various exosomal cargos miRNAs represent the most abundant molecules contained in the exosomes and represent one of the most important exosomal cargos in influencing diverse cellular functions through transcriptional and post-transcriptional regulation (Dragomir et al., 2018; Isaac et al., 2021). The study by Zhang et al. showed that exercise-induced exosomes increased the expression of key osteogenic transcription factors like, Runx2, osteocalcin, osteopontin, and type I collagen which are the main regulators of osteoblast differentiation and bone matrix formation. The identification of miR-206 as the most significantly upregulated miRNA reinforces the role of exosomes in supporting the epigenetics of musculoskeletal regeneration. miR-206 is known to be involved in the regulation of osteoblast differentiation, ossification, and stem cell proliferation; therefore, increased expression of miR-206 strengthens the potential for musculoskeletal regeneration (Zhang et al., 2025).
The consistency of the role of miRNAs is reinforced by the findings of de Mendonça et al. and Watanabe et al. reporting that exosomes derived from both circulation and skeletal muscle interstitium contains miRNAs associated with musculoskeletal function and metabolic adaptation (de Mendonça et al., 2020; Watanabe et al., 2022). Findings were obtained describing correlations between miR-192 and miR-122 with the gastrocnemius muscle in physical exercise model indicating that exosomal miRNAs contribute to interorgan communication and the functional status of the musculoskeletal tissue (de Mendonça et al., 2020). Meanwhile, the findings of Watanabe et al. reported that skeletal muscle interstitial exosomes are enriched with myomiRs, structural proteins and muscle metabolic proteins indicating that local exosomes may potentially exert more specific effects on musculoskeletal regeneration (Watanabe et al., 2022).
Overall, this systematic synthesis of preclinical studies reports that the regenerative effects of exercise-induced exosomes operate effectively through synergistic interactions between metabolic proteins that supports the cellular energy requirements and miRNAs; this synergy leads to a molecular environment conducive to osteogenesis and musculoskeletal regeneration while also emphasizing exercise-induced exosomes as mediators that integrates, metabolic and epigenetic regulation in tissue repair processes. Findings from previous studies further reaffirm the important role of miRNAs encapsulated within musculoskeletal-derived exosomes in regulating pathways related to muscle quality control, calcium signaling and neuromuscular function (Miao et al., 2021; Nakamura et al., 2015; B. Yue et al., 2020).
THERAPEUTIC EFFECTS ON THE MUSCULOSKELETAL SYSTEM
The study by Ma et al. performed exosome injection from the physical exercise model group into a disuse osteoporosis model, which was observed through micro-CT scanning to assess whether exosome supplementation could protect against or repair the disuse osteoporosis model. The results reported that after exosome injection there was improvement in trabecular bone loss, increased bone volume fraction, trabecular number, cortical bone thickness, and connectivity density, and reduced trabecular separation (Ma et al., 2023).
Histomorphometric analysis also showed an increased mineral apposition rate in the distal femur, and through immunofluorescence staining an increase in osteoblast cells or cells involved in bone formation was identified. As integrated components within the musculoskeletal system, muscle and bone often exhibit coordinated development and growth. Therefore, many findings from previous studies support the presence of cross-communication signaling between muscle and bone through circulating and local biological mediators. These findings further strengthen the role of exosomes in bone regeneration and identify them as important bioactive factors in the interaction between muscle and bone metabolism (Ma et al., 2023; Pluchino & Smith, 2019).
In the study by Zhang et al., the role of exosomes isolated from the physical exercise model group (exe-exos) was explored, with supplementation in an osteoporosis model through tail vein injection for 8 weeks. The results showed a significant increase in bone mass and a marked increase in cortical bone thickness (Zhang et al., 2025). H&E staining revealed increased trabecular density beneath the epiphyseal plate and an increased trabecular area. In addition, examination using calcein staining to assess the bone formation rate reported a significant increase in cortical and trabecular bone formation rates in the model receiving exosome supplementation compared with control (Zhang et al., 2025).
Findings from the study by Zhang et al. also reported that exe-exos supplementation did not affect osteoclast formation, but significantly increased the number of osteoblasts (p = 0.01) and the expression of osteogenic-related genes such as Runx2, Col1, OPN, and OCN. Exe-exos supplementation simultaneously increased H-type blood vessels beneath the epiphyseal plate, indicating that supplementation promoted bone formation and improved bone metabolic balance (Zhang et al., 2025). This is consistent with previous studies reporting that exosomes, particularly those derived from BMSCs (BMSC-Exos), play an important role in promoting angiogenesis (Soni et al., 2021).
Preclinical evidence from the study by de Mendonça et al. shows that miRNAs contained in exercise-induced exosomes play a role in communication between adipose tissue, the liver, and skeletal muscle. This study used an obese mouse model and demonstrated that aerobic exercise significantly altered the miRNA profile in serum exosomes and correlated with increased insulin sensitivity in skeletal muscle, as indicated by increased expression of GLUT4 and IRS1 in the gastrocnemius muscle (de Mendonça et al., 2020). These findings strengthen the role of exosomes as key mediators of muscle molecular adaptation induced by physical exercise. Furthermore, the work by Watanabe et al. investigated the function of myomiRs found in interstitial exosomes, and the results revealed that myomiRs derived from interstitial exosomes promote myoblast differentiation via the suppression of Pax7 expression and the upregulation of MyHC expression, which is a marker of the myoblast differentiation process. The study established how myogenesis is augmented by myomiRs carried by exercise-induced exosomes through the inhibition of Pax7 expression (Watanabe et al., 2022).
CONCLUSION
Conclusively, this review indicates that exercise-induced exosomes are powerful regulators of musculoskeletal regeneration. The mechanisms by which exosomes mediate therapeutic effects are diverse and include both protein and RNA-mediated pathways. While the protein cargo provides metabolic support to recipient cells by providing enzymes involved in glycolysis, which supplies the energy needed for tissue repair and remodeling, the RNA fraction, which is mostly constituted by miRNAs, acts as an epigenetic regulator of osteogenic or myogenic differentiation. This evidence offers new insights into the therapeutic potential of exosomes and provides a rationale for the development of targeted treatments against degenerative musculoskeletal diseases, such as osteoporosis and sarcopenia. Exercise-induced exosomes can be harnessed as “exercise mimetics” to provide a form of systemically administered therapy that can supplement the endogenous regenerative response to physical activity and offer a comprehensive treatment by combining the modulation of the metabolic microenvironment with tissue repair and remodeling cues. Consequently, the application of exercise-induced exosomes appears to be a promising strategy to promote holistic and precision-guided musculoskeletal recovery in the future.
By: Nohan Noer Adnan
Write and Win: Participate in Creative writing Contest & International Essay Contest and win fabulous prizes.
About the Author
