Exosomes derived from adipose stem cells in combination with hyaluronic acid promote diabetic wound healing

Recent advances in hyaluronic acid-based hydrogels for diabetic wound healing

Diabetic wound healing represents a complex biological challenge, often impeded by disrupted cellular processes and dysregulated inflammation, which can lead to chronic and non-healing wounds. Given the significant burden on patients and the healthcare system, there is an urgent need for advanced therapeutic strategies. Hyaluronic acid (HA)-based hydrogels have emerged as a promising solution due to their biocompatibility, biodegradability, and unique physiological functions. This review aims to provide a comprehensive overview of recent advances in HA-based hydrogels, highlighting their potential in addressing diabetic wound complications. Specifically, it examines challenges such as hyperglycemia-induced oxidative stress and impaired cellular signaling within the intricate diabetic wound microenvironment. Moreover, the review explores the composition and properties of HA, including its adhesive capabilities and role in reducing surgical trauma. Various crosslinking strategies and functional modifications are also discussed to endow HA-based hydrogels with antioxidant, antimicrobial, and growth factor-releasing capabilities. By summarizing the latest research and identifying areas for further exploration, this review contributes to the development of more effective HA-based hydrogel formulations for diabetic wound healing.

Exosomes derived from adipose mesenchymal stem cells promote corneal injury repair and inhibit the formation of scars by anti-apoptosis

In the corneal wound healing process, epithelial cell re-epithelialization and migration are the critical first steps following an injury. As the disease progresses, orderly regeneration of corneal stromal collagen and mild corneal stromal fibrosis are vital for corneal function reconstruction. Exosomes derived from adipose-derived mesenchymal stem cells (ADSCs-Exos) have emerged as a promising therapy due to their anti-oxidant, anti-apoptosis, and tissue repair properties. In this study, we successfully isolated exosomes via differential centrifugation and verified their effective extraction through transmission electron microscopy and nanoparticle tracking analysis. In vitro, ADSCs-Exos increased corneal epithelial cell migration by 20 % and reduced oxidative damage by 50 %. In addition, ADSCs-Exos demonstrated remarkable wound healing properties in corneal tissue. This effect was attributed to their ability to inhibit apoptosis of corneal stroma cells by upregulating Bax and downregulating Bcl2, reducing the Bax/Bcl2 protein expression ratio from 1 to 0.45. This decrease may subsequently inhibit α-SMA expression, thereby preventing corneal scarring. Overall, this research has elucidated the effects and potential targets of ADSCs-Exos in promoting corneal wound repair, offering a novel and promising approach for treating corneal injuries.

Transplantation of hyaluronic acid and menstrual blood-derived stem cells accelerated wound healing in a diabetic rat model

Diabetic wounds require a multifactorial approach because several factors are involved in its occurrence. Herein we investigated whether transplantation of hyaluronic acid (HA) in combination with menstrual blood derived stem cells (MenSCs) could promote healing in diabetic rats. Thirty days after induction of diabetes, sixty animals were randomly planned into four equal groups: the untreated group, HA group, MenSC group, and HA+MenSC group. Sampling was done for histological, molecular, and tensiometrical assessments. Our results indicated that the wound contraction rate, volumes of new epidermis and dermis, collagen density, as well as tensiometrical parameter were considerably increased in the treatment groups compared to the untreated group and these changes were more obvious in the HA+MenSC ones. In addition, the expression levels of TGF-β and VEGF genes were significantly upregulated in treatment groups in comparison with the untreated group and were greater in the HA+MenSC group. This is while expression levels of TNF-α and IL-1β genes were more considerably downregulated in the HA+MenSC group than the other groups. We concluded that the combined use of HA and MenSCs has more effects on diabetic wound healing.

A comprehensive review of engineered exosomes from the preparation strategy to therapeutic applications

Exosomes exhibit high bioavailability, biological stability, targeted specificity, low toxicity, and low immunogenicity in shuttling various bioactive molecules such as proteins, lipids, RNA, and DNA. Natural exosomes, however, have limited production, targeting abilities, and therapeutic efficacy in clinical trials. On the other hand, engineered exosomes have demonstrated long-term circulation, high stability, targeted delivery, and efficient intracellular drug release, garnering significant attention. The engineered exosomes bring new insights into developing next-generation drug delivery systems and show enormous potential in therapeutic applications, such as tumor therapies, diabetes management, cardiovascular disease, and tissue regeneration and repair. In this review, we provide an overview of recent advancements associated with engineered exosomes by focusing on the state-of-the-art strategies for cell engineering and exosome engineering. Exosome isolation methods, including traditional and emerging approaches, are systematically compared along with advancements in characterization methods. Current challenges and future opportunities are further discussed in terms of the preparation and application of engineered exosomes.

Advancing Tissue Damage Repair in Geriatric Diseases: Prospects of Combining Stem Cell-Derived Exosomes with Hydrogels

Geriatric diseases are a group of diseases with unique characteristics related to senility. With the rising trend of global aging, senile diseases now mainly include endocrine, cardiovascular, neurodegenerative, skeletal, and muscular diseases and cancer. Compared with younger populations, the structure and function of various cells, tissues and organs in the body of the elderly undergo a decline as they age, rendering them more susceptible to external factors and diseases, leading to serious tissue damage. Tissue damage presents a significant obstacle to the overall health and well-being of older adults, exerting a profound impact on their quality of life. Moreover, this phenomenon places an immense burden on families, society, and the healthcare system.In recent years, stem cell-derived exosomes have become a hot topic in tissue repair research. The combination of these exosomes with biomaterials allows for the preservation of their biological activity, leading to a significant improvement in their therapeutic efficacy. Among the numerous biomaterial options available, hydrogels stand out as promising candidates for loading exosomes, owing to their exceptional properties. Due to the lack of a comprehensive review on the subject matter, this review comprehensively summarizes the application and progress of combining stem cell-derived exosomes and hydrogels in promoting tissue damage repair in geriatric diseases. In addition, the challenges encountered in the field and potential prospects are presented for future advancements.

The Efficacy of Stem Cells in Wound Healing: A Systematic Review

Wound healing is an intricate process involving coordinated interactions among inflammatory cells, skin fibroblasts, keratinocytes, and endothelial cells. Successful tissue repair hinges on controlled inflammation, angiogenesis, and remodeling facilitated by the exchange of cytokines and growth factors. Comorbid conditions can disrupt this process, leading to significant morbidity and mortality. Stem cell therapy has emerged as a promising strategy for enhancing wound healing, utilizing cells from diverse sources such as endothelial progenitor cells, bone marrow, adipose tissue, dermal, and inducible pluripotent stem cells. In this systematic review, we comprehensively investigated stem cell therapies in chronic wounds, summarizing the clinical, translational, and primary literature. A systematic search across PubMed, Embase, Web of Science, Google Scholar, and Cochrane Library yielded 22,454 articles, reduced to 44 studies after rigorous screening. Notably, adipose tissue-derived mesenchymal stem cells (AD-MSCs) emerged as an optimal choice due to their abundant supply, easy isolation, ex vivo proliferative capacities, and pro-angiogenic factor secretion. AD-MSCs have shown efficacy in various conditions, including peripheral arterial disease, diabetic wounds, hypertensive ulcers, bullous diabeticorum, venous ulcers, and post-Mohs micrographic surgery wounds. Delivery methods varied, encompassing topical application, scaffold incorporation, combination with plasma-rich proteins, and atelocollagen administration. Integration with local wound care practices resulted in reduced pain, shorter healing times, and improved cosmesis. Stem cell transplantation represents a potential therapeutic avenue, as transplanted stem cells not only differentiate into diverse skin cell types but also release essential cytokines and growth factors, fostering increased angiogenesis. This approach holds promise for intractable wounds, particularly chronic lower-leg wounds, and as a post-Mohs micrographic surgery intervention for healing defects through secondary intention. The potential reduction in healthcare costs and enhancement of patient quality of life further underscore the attractiveness of stem cell applications in wound care. This systematic review explores the clinical utilization of stem cells and stem cell products, providing valuable insights into their role as ancillary methods in treating chronic wounds.