Exposure to the external environment may lead to instability and dysfunction of the skin, resulting in refractory wound, skin aging, pigmented dermatosis, hair loss, some immune-mediated dermatoses, and connective tissue diseases. Nowadays, many skin treatments have not achieved a commendable balance between medical recovery and cosmetic needs. Exosomes are cell-derived nanoscale vesicles carrying various biomolecules, including proteins, nucleic acids, and lipids, with the capability to communicate with adjacent or distant cells. Recent studies have demonstrated that endogenic multiple kinds of exosomes are crucial orchestrators in shaping physiological and pathological development of the skin. Besides, exogenous exosomes, such as stem cell exosomes, can serve as novel treatment options to repair, regenerate, and rejuvenate skin tissue. Herein, we review new insights into the role of endogenic and exogenous exosomes in the skin microenvironment and recent advances in applications of exosomes related to dermatology and cutaneous medical aesthetics. The deep understanding of the mechanisms by which exosomes perform biological functions in skin is of great potential to establish attractive therapeutic methods for the skin.

Adipose-derived stem cells (ASCs) are an important stem cell type separated from adipose tissue, with the properties of multilineage differentiation, easy availability, high proliferation potential, and self-renewal. Exosomes are novel frontiers of intercellular communication regulating the biological behaviors of cells, such as angiogenesis, immune modulation, proliferation, and migration. ASC-derived exosomes (ASC-exos) are important components released by ASCs paracrine, possessing multiple biological activities. Tissue regeneration requires coordinated “vital networks” of multiple growth factors, proteases, progenitors, and immune cells producing inflammatory cytokines. Recently, as cell-to-cell messengers, ASC-exos have received much attention for the fact that they are important paracrine mediators contributing to their suitability for tissue regeneration. ASC-exos, with distinct properties by encapsulating various types of bioactive cargoes, are endowed with great application potential in tissue regeneration, mechanically via the migration and proliferation of repair cells, facilitation of the neovascularization, and other specific functions in different tissues. Here, this article elucidated the research progress of ASC-exos about tissue regeneration in plastic and cosmetic surgery, including skin anti-aging therapy, dermatitis improvement, wound healing, scar removal, flap transplantation, bone tissue repair and regeneration, obesity prevention, fat grafting, breast cancer, and breast reconstruction. Deciphering the biological properties of ASC-exos will provide further insights for exploring novel therapeutic strategies of tissue regeneration in plastic and cosmetic surgery.

Skin tissue, composed of epidermis, dermis, and subcutaneous tissue, is the largest organ of the human body. It serves as a protective barrier against pathogens and physical trauma and plays a crucial role in maintaining homeostasis. Skin diseases, such as psoriasis, dermatitis, and vitiligo, are prevalent and can seriously impact the quality of patient life. Exosomes are lipid bilayer vesicles derived from multiple cells with conserved biomarkers and are important mediators of intercellular communication. Exosomes from skin cells, blood, and stem cells, are the main types of exosomes that are involved in modulating the skin microenvironment. The dysregulation of exosome occurrence and transmission, as well as alterations in their cargoes, are crucial in the complex pathogenesis of inflammatory and autoimmune skin diseases. Therefore, exosomes are promising diagnostic and therapeutic targets for skin diseases. Importantly, exogenous exosomes, derived from skin cells or stem cells, play a role in improving the skin environment and repairing damaged tissues by carrying various specific active substances and involving a variety of pathways. In the domain of clinical practice, exosomes have garnered attention as diagnostic biomarkers and prospective therapeutic agents for skin diseases, including psoriasis and vitiligo. Furthermore, clinical investigations have substantiated the regenerative efficacy of stem cell-derived exosomes in skin repair. In this review, we mainly summarize the latest studies about the mechanisms and applications of exosomes in dermatology, including psoriasis, atopic dermatitis, vitiligo, systemic lupus erythematosus, systemic sclerosis, diabetic wound healing, hypertrophic scar and keloid, and skin aging. This will provide a novel perspective of exosomes in the diagnosis and treatment of dermatosis.

Keloid, a common dermal fibroproliferative disorder, is benign skin tumors characterized by the aggressive fibroblasts proliferation and excessive accumulation of extracellular matrix. However, common therapeutic approaches of keloid have limited effectiveness, emphasizing the momentousness of developing innovative mechanisms and therapeutic strategies. Epigenetics, representing the potential link of complex interactions between genetics and external risk factors, is currently under intense scrutiny. Accumulating evidence has demonstrated that multiple diverse and reversible epigenetic modifications, represented by DNA methylation, histone modification, and non-coding RNAs (ncRNAs), play a critical role in gene regulation and downstream fibroblastic function in keloid. Importantly, abnormal epigenetic modification manipulates multiple behaviors of keloid-derived fibroblasts, which served as the main cellular components in keloid skin tissue, including proliferation, migration, apoptosis, and differentiation. Here, we have reviewed and summarized the present available clinical and experimental studies to deeply investigate the expression profiles and clarify the mechanisms of epigenetic modification in the progression of keloid, mainly including DNA methylation, histone modification, and ncRNAs (miRNA, lncRNA, and circRNA). Besides, we also provide the challenges and future perspectives associated with epigenetics modification in keloid. Deciphering the complicated epigenetic modification in keloid is hopeful to bring novel insights into the pathogenesis etiology and diagnostic/therapeutic targets in keloid, laying a foundation for optimal keloid ending.

Diabetic wounds are characterized by delayed and incomplete healing. As one of the most common complications of diabetes, diabetic wounds can be fatal in some cases. Programmed cell death (PCD) is an active and ordered cell death mode determined by genes, including apoptosis, autophagy, pyroptosis, necroptosis, ferroptosis, and cuproptosis. It is currently believed that PCD plays a crucial role in diabetic wound healing. Diabetic hyperglycemic environments can lead to abnormal PCD in various cells during healing processes, thereby affecting the activity and function of cells and interfering with diabetic wound healing. Therefore, this review focuses on the new roles and mechanisms of PCD in diabetic wound healing. Moreover, the challenges and perspectives related to PCD in diabetic wound healing are presented, which will bring new insights to improve diabetic wound healing.

Wound healing is a complex, multi-stage process that restores skin integrity through coordinated cellular and molecular interactions. Among the emerging therapeutic strategies, adipose-derived stem cell exosomes (ADSC-Exos) attract significant attention due to their potent regenerative capabilities. ADSC-Exos contribute to wound repair by modulating inflammatory responses, promoting cellular proliferation and migration, stimulating angiogenesis, and facilitating collagen remodeling. These exosomes carry a diverse array of bioactive molecules including cytokines, non-coding RNAs (ncRNAs), and proteins, that are delivered to target cells, thereby orchestrating the intricate processes involved in tissue regeneration. Recent advancements in exosome engineering, such as genetic modification, pharmacological preconditioning, hypoxic treatment, and incorporation with biomaterials, markedly improve the therapeutic efficacy of ADSC-Exos. This review summarizes the underlying mechanisms and therapeutic potential of ADSC-Exos in wound healing, offering new perspectives for developing exosome-based regenerative therapies. Nevertheless, challenges persist regarding the large-scale production, standardized isolation, and clinical translation of ADSC-Exos. Future research should aim to enhance exosome yield and purity, elucidate the mechanisms governing exosome biogenesis, and validate their clinical efficacy through well-designed trials.