Effects of exosomes derived from fibroblast cells on skin wound healing in Wistar rats

Extracellular vesicle as therapeutic agents in anti-aging: Mechanistic insights and future potential

Aging is a multifaceted biological process marked by a gradual decline in physiological functions, driven by cellular senescence, oxidative stress, chronic inflammation, and stem cell exhaustion. Extracellular vesicles (EVs), naturally occurring nanoscale vesicles secreted by various cell types, have gained attention as potential therapeutic agents due to their ability to mediate intercellular communication by delivering bioactive molecules, including proteins, lipids, and RNAs. This review provides a comprehensive overview of EV biogenesis, cargo composition, and their mechanistic roles in counteracting aging processes. EVs from diverse sources-such as mesenchymal stem cells, embryonic stem cells, dermal fibroblasts, and colostrum-exhibit regenerative properties by modulating immune responses, enhancing tissue repair, and promoting extracellular matrix homeostasis. Recent preclinical and clinical studies further highlight their potential in addressing age-related diseases and skin rejuvenation. However, significant challenges remain, including standardization of EV production, large-scale manufacturing, safety profiling, and regulatory approval. By leveraging advancements in EV engineering, targeted delivery systems, and combination strategies with existing anti-aging interventions, EV-based therapies hold promise as next-generation approaches in regenerative medicine and longevity enhancement.

Orchestration of Macrophage Polarization Dynamics by Fibroblast-Secreted Exosomes during Skin Wound Healing

Macrophages undertake pivotal yet dichotomous functions during skin wound healing, mediating both early proinflammatory immune activation and late anti-inflammatory tissue remodeling processes. The timely phenotypic transition of macrophages from inflammatory M1 to proresolving M2 activation states is essential for efficient healing. However, the endogenous mechanisms calibrating macrophage polarization in accordance with the evolving tissue milieu remain undefined. In this study, we reveal an indispensable immunomodulatory role for fibroblast-secreted exosomes in directing macrophage activation dynamics. Fibroblast-derived exosomes permitted spatiotemporal coordination of macrophage phenotypes independent of direct intercellular contact. Exosomes enhanced macrophage sensitivity to both M1 and M2 polarizing stimuli, yet they also accelerated timely switching from M1 to M2 phenotypes. Exosome inhibition dysregulated macrophage responses, resulting in aberrant inflammation and impaired healing, whereas provision of exogenous fibroblast-derived exosomes corrected defects. Topical application of fibroblast-derived exosomes onto chronic diabetic wounds normalized dysregulated macrophage activation to resolve inflammation and restore productive healing. Our findings elucidate fibroblast-secreted exosomes as remote programmers of macrophage polarization that calibrate immunological transitions essential for tissue repair. Harnessing exosomes represents a previously unreported approach to steer productive macrophage activation states with immense therapeutic potential for promoting healing in chronic inflammatory disorders.

Application of exosomes for the regeneration of skin wounds: Principles, recent applications and limitations

In the medical field, wound healing poses significant challenges due to its complexity and time-consuming nature. Cell-free wound repair, notably the utilization of exosomes (EXOs), has made significant progress in recent years. Urine, saliva, umbilical cord, blood, mesenchymal stem cells and breast milk cells can be used to extract and purify EXOs, which are Nano-sized lipid bilayer vesicles. Besides their relatively little toxicity, non-specific immunogenicity and excellent biocompatibility, EXOs also contain bioactive molecules such as proteins, lipids, microRNAs (miRNAs), and messenger RNAs (mRNAs). Their bioactive compounds have anti-inflammatory properties and can speed up wound healing. Various medicinal agents can also be contained within the EXOs. This review briefly provides new information on the different aspects of EXOs and evaluate the application of EXOs as a promising therapy in the regeneration of skin wounds in recent pre-clinical and clinical studies.

The regenerative effect of exosomes isolated from mouse embryonic fibroblasts in mice created as a sciatic nerve crush injury model

BACKGROUND

Exosomes (Exos) are candidates for functional recovery and regeneration following sciatic nerve crushed (SNC) injury due to their composition which can accelerate tissue regeneration. Therefore, mouse embryonic fibroblast-derived exosomes were evaluated for their regenerative capacity in SNC injury.

METHODS AND RESULTS

In the study, 40 Balb/c males (20 ± 5 g) and two pregnant mice (for embryonic fibroblast tissue) were used and crushed injury was induced in the left sciatic nerve with an aneurysm clamp. Sciatic nerve model mice were randomly divided into 5 groups (n = 8; control, n = 8; sham, n = 8; SNC, n = 8; Mouse embryonic fibroblast exosome (mExo), n = 8; SNC + Mouse embryonic fibroblast exosome (SNC + mExo). Rotarod tests for motor functions and hot plate and von Frey tests for sensory functions were analyzed in the groups. Expression changes of exosome genes (RARRES1, NAGS, HOXA13, and MEIS1) immunohistochemical analysis of these gene proteins, and structural exosome NF-200 and S100 proteins were evaluated by confocal microscopy. Behavioral analyses showed that the damage in SNC was significant between groups on day14 and day28 (P < 0.05). In behavioral analyses, it was determined that motor functions and mechanical sensitivity lost in SNC were regained after mExo treatment. While expression of all genes was detected in MEF-derived exosomes, the high expression was MESI1 and the low expression was HOXA13. NF200, an indicator of axon number and neurofilament density, was found to decrease in SNC (P < 0.001) and increase after treatment, but not significantly. The decreased S100 protein levels in SNC and the increase detected after treatment were not significant.

CONCLUSION

The expression of four mRNAs in mExos indicates that these genes may have an effect on regenerative processes after SNC injury. The regenerative process supported by tissue protein expressions demonstrates the therapeutic potential of mExo treatment.

Comparative Analysis of Exosomes and Extracellular Microvesicles in Healing Pathways: Insights for Advancing Regenerative Therapies

Exosomes and microvesicles bear great potential to broaden therapeutic options in the clinical context. They differ in genesis, size, cargo, and composition despite their similarities. They were identified as participating in various processes such as angiogenesis, cell migration, and intracellular communication. Additionally, they are characterized by their natural biocompatibility. Therefore, researchers concluded that they could serve as a novel curative method capable of achieving unprecedented results. Indeed, in experiments, they proved remarkably efficient in enhancing wound regeneration and mitigating inflammation. Despite immense advancements in research on exosomes and microvesicles, the time for their large-scale application is yet to come. This article aims to gather and analyze current knowledge on those promising particles, their characteristics, and their potential clinical implementations.

Patient-Derived Exosomes as siRNA Carriers in Ovarian Cancer Treatment

RNA interference is a powerful gene-silencing tool with potential clinical applications. However, its therapeutic use is challenging because suitable carriers are unavailable. Exosomes are stable small endogenous vesicles that can transport functional molecules to target cells, making them ideal small interfering RNA (siRNA) carriers. Herein, we elucidated the therapeutic potential of patient-derived exosomes as an siRNA carrier for ovarian cancer (OC) treatment. The exosomes were extracted from the culture medium of primary fibroblasts collected from the omentum of patients with OC during surgery. MET proto-oncogene, receptor tyrosine kinase (MET) was selected for gene silencing, c-Met siRNAs were synthesized and loaded into the exosomes (Met-siExosomes) via electroporation, and the treatment effect of the Met-siExosomes was assessed in vitro and in vivo. The Met-siExosomes downregulated the c-Met protein levels and inhibited OC cell proliferation, migration, and invasion. In xenograft experiments using SKOV3-13 and ES-2 cells, Met-siExosomes were selectively extracted from peritoneally disseminated tumors. Intraperitoneal treatment suppressed the c-Met downstream targets in cancer cells and prolonged mouse survival. The synthesized siRNAs were successfully and selectively delivered via the exosomes to intraperitoneally disseminated tumors. As patients with OC routinely undergo omentectomy and abundant fibroblasts can be easily collected from the omentum, patient-derived exosomes may represent a promising therapeutic siRNA carrier to treat OC.

The Innovative and Evolving Landscape of Topical Exosome and Peptide Therapies: A Systematic Review of the Available Literature

Topical antiaging therapies provide noninvasive delivery of active therapeutics. Exosomes, or extracellular nanovesicles, and peptides, small strings of amino acids, have shown promise as topical therapies in early trials, but neither is FDA approved. This review aims to elucidate the current and future landscape of topical exosomes and peptides as therapeutics for skin rejuvenation. A literature search was conducted using the keywords "peptides" OR "exosomes" AND "skin" OR "rejuvenation." Primary endpoints included mechanisms of action in humans or live animals as well as clinical data supporting the use of exosomes or peptides topically for skin rejuvenation or wound healing. Secondary endpoints were safety, side effects, and efficacy. The articles were collected, organized, and sorted using the Covidence software (Melbourne, Australia) for systematic review. Nine articles evaluating topical application of exosomes and 9 of peptides met inclusion criteria. Topical exosomes were found to increase collagen deposition, accelerate wound healing, and improve overall cosmesis. Several clinical trials are currently underway. Topical peptides were found to improve appearance of fine lines and wrinkles, elasticity and viscoelasticity, skin texture, skin thickness, and the potential for accelerated wound healing. Peptides are quite common in "cosmeceutical" products, and several patents have been filed for topical peptide products aimed at increasing skin rejuvenation. This could indicate a movement toward pursuing FDA approval. The future of topical exosome and peptide products for the purpose of skin rejuvenation appears promising. Preliminary data from the studies reviewed here indicates that these products have the potential to be safe and effective.

Level of Evidence 3

Extracellular vesicles and their engineering strategies, delivery systems, and biomedical applications

Extracellular vesicles are nanoscale vesicles that can be secreted by all cell types, are intracellular in origin and have the same composition as their parent cells, play a key role in intercellular communication in organismal health and disease, and are now often used as biomarkers of disease and therapeutic agents in biomedical research. When injected locally or systemically, they have the ability to provide a variety of therapeutic effects, for example, regeneration of skin damage or restoration of cardiac function. However, direct injection of extracellular vesicles may result in their rapid clearance from the injection site.In order to maintain the biological activity of extracellular vesicles and to control the release of effective concentrations for better therapeutic efficacy during long-term disease treatment, the design of an optimized drug delivery system is necessary and different systems for the continuous delivery of extracellular vesicles have been developed. This paper first provides an overview of the biogenesis, composition and physiological function of extracellular vesicles, followed by a review of different strategies for extracellular vesicle isolation and methods for engineering extracellular vesicles. In addition, this paper reviews the latest extracellular vesicle delivery platforms such as micro-nanoparticles, injectable hydrogels, microneedles and scaffold patches. At the same time, the research progress and key cases of extracellular vesicle delivery systems in the field of biomedical therapeutics are described. Finally, the challenges and future trends of extracellular vesicle delivery are discussed.

Advancements and Insights in Exosome-Based Therapies for Wound Healing: A Comprehensive Systematic Review (2018-June 2023)

Exosomes have shown promising potential as a therapeutic approach for wound healing. Nevertheless, the translation from experimental studies to commercially available treatments is still lacking. To assess the current state of research in this field, a systematic review was performed involving studies conducted and published over the past five years. A PubMed search was performed for English-language, full-text available papers published from 2018 to June 2023, focusing on exosomes derived from mammalian sources and their application in wound healing, particularly those involving in vivo assays. Out of 531 results, 148 papers were selected for analysis. The findings revealed that exosome-based treatments improve wound healing by increasing angiogenesis, reepithelization, collagen deposition, and decreasing scar formation. Furthermore, there was significant variability in terms of cell sources and types, biomaterials, and administration routes under investigation, indicating the need for further research in this field. Additionally, a comparative examination encompassing diverse cellular origins, types, administration pathways, or biomaterials is imperative. Furthermore, the predominance of rodent-based animal models raises concerns, as there have been limited advancements towards more complex in vivo models and scale-up assays. These constraints underscore the substantial efforts that remain necessary before attaining commercially viable and extensively applicable therapeutic approaches using exosomes.