P-MSC-derived extracellular vesicles facilitate diabetic wound healing via miR-145-5p/ CDKN1A-mediated functional improvements of high glucose-induced senescent fibroblasts

Molecular insights into diabetic wound healing: Focus on Wnt/β-catenin and MAPK/ERK signaling pathways

Diabetic wounds manifest significant clinical challenge with approximately 50-70 % reporting non-traumatic lower limb amputations annually. This review examines the intricate relationship between impaired wound healing in diabetes mellitus and two crucial signaling pathways: Wnt/β-catenin and MAPK/ERK. Chronic hyperglycemia in diabetes mellitus leads to peripheral neuropathy, vascular dysfunction, and compromised immune responses, resulting in delayed wound healing. The Wnt/β-catenin pathway, which is essential for cellular proliferation, differentiation, and tissue homeostasis, shows altered activity in diabetic wounds, particularly through decreased R-spondin 3 protein expression. Similarly, the MAPK/ERK pathway, which regulates cellular proliferation and differentiation through hierarchical kinase cascades, exhibits dysregulation under diabetic conditions. This review describes the current understanding of normal wound healing processes, diabetic wound pathophysiology, and the molecular mechanisms of both signaling pathways. Evidence suggests that targeting these pathways, either individually or synergistically offer promising therapeutic approaches for diabetic wound management. Future directions include, developing targeted delivery systems, exploring pathway cross-talk, and investigating dual-pathway modulators to enhance wound healing outcomes in diabetic patients. This comprehensive analysis provides insights into potential therapeutic strategies and emphasizes the necessity of research in this crucial area of diabetes treatment. (Graphical Abstract).

miR-145-enriched BMSCs-derived exosomes ameliorate neurogenic erectile dysfunction in aged rats via TGFBR2 inhibition

Background

Neurogenic erectile dysfunction (ED) is a prevalent complication following radical prostatectomy in elderly patients, primarily resulting from the apoptosis of corpus cavernosum smooth muscle cells (CCSMCs) and the subsequent excessive fibrosis of the corpus cavernosum.

Aim

This study aimed to compare the therapeutic effects of exosomes derived from lentivirus-transfected miR-145 bone marrow mesenchymal stem cells (Exo-145) and unmodified BMSCs-derived exosomes (Exo) in aged rats with bilateral cavernous nerve injury (BCNI) and investigate the underlying mechanisms.

Methods

Twenty-four-month-old male rats were assigned to four groups, namely Sham, BCNI, Exo, and Exo-145. Three weeks after treatment, erectile function was assessed by measuring the maximal intracavernosal pressure to mean arterial pressure (ICP/MAP) ratio. Apoptosis and fibrosis were semi-quantitatively analyzed using TUNEL and Masson's trichrome staining, respectively. In vitro, CCSMCs were subjected to H2O2-induced oxidative stress, and the protective effects of Exo-145 were evaluated through flow cytometry and Western blot. Lastly, the targets and mechanisms of miR-145 were further validated using dual-luciferase reporter assays and rescue experiments.

Results

Exo-145 significantly outperformed Exo in restoring erectile function in aged BCNI rats, as evidenced by the significantly higher maximal ICP/MAP ratio, a marked reduction in TUNEL-positive cell count, and marked suppression of fibrosis in cavernous tissue. Moreover, Masson's trichrome staining displayed a substantial decrease in collagen deposition. In vitro, Exo-145 alleviated H2O2-induced apoptosis in CCSMCs by downregulating Cleaved Caspase-3 expression and Bax while concurrently upregulating Bcl-2 expression. TGFBR2 was identified as a direct target of miR-145 through dual-luciferase reporter assays, with its overexpression partially reversing the protective effects of Exo-145.

Conclusion

Exo-145 demonstrates superior efficacy compared to Exo in treating aged neurogenic ED by targeting TGFBR2 to alleviate apoptosis and fibrosis. It may represent a promising cell-free therapeutic option for neurogenic erectile dysfunction in elderly patients and could offer new perspectives for improving their prognosis.

Ellagic Acid-Loaded sEVs Encapsulated in GelMA Hydrogel Accelerate Diabetic Wound Healing by Activating EGFR on Skin Repair Cells

Delayed diabetic wound healing is partially attributed to the functional disorder of skin repair cells caused by high glucose (HG). Small extracellular vehicles (sEVs) loaded with small-molecule drugs represent a highly promising therapeutic strategy. This study aims to evaluate the therapeutic efficacy of ellagic acid-encapsulated small extracellular vesicles (EA-sEVs) in diabetic wound regeneration and to unravel related mechanisms. Cytotoxicity tests of ellagic acid (EA) as liposomal small molecules (LSMs) were performed with the CCK8 assay. EA was incorporated into sEVs obtained from chorionic plate-mesenchymal stem cells (CP-MSCs) to construct EA-engineered sEVs. The protective effects of EA-sEVs on human dermal fibroblasts (HDFs) and human epidermal keratinocytes (HEKs) induced by high glucose (HG) were assessed through the evaluation of their proliferative, migrative and differentiative capabilities. Furthermore, to illustrate the underlying mechanism, the specific biological targets of EA were predicted and confirmed. Finally, EA-sEVs were encapsulated in GelMA hydrogel for investigating the pro-healing effects on diabetic wounds. EA was harmless to cell viability, increasing the possibility and safety of drug development. EA-engineered sEVs were fabricated by loading EA in sEVs. In vitro, EA-sEVs promoted the proliferation, migration, and transdifferentiation of HG-HDFs and the proliferation and migration of HG-HEKs. Mechanism analysis elucidated that epidermal growth factor receptor (EGFR) was the specific biological target of EA. EA interacting with EGFR was responsible for the functional improvement of HG-HDFs and HG-HEKs. In vivo, EA-sEVs encapsulated in GelMA promoted the healing of diabetic wounds by improving re-epithelialisation, collagen formation and the expression of EGFR. Gel-EA-sEVs promoted diabetic wound healing by improving biological functions of HDFs and HEKs. EGFR was first identified as the specific biological target of EA and was responsible for the functional improvement of HG-HDFs and HG-HEKs by Gel-EA-sEVs. Hence, Gel-EA-sEVs can serve as a new promising active dressing for diabetic wound treatment.

Role of mesenchymal stromal cell secretome on recovery from cellular senescence: an overview

Cellular senescence is intricately linked with numerous changes observed in the aging process, including the depletion of the stem cell pool and the decline in tissue and organ functions. Over the past three decades, efforts to halt and reverse aging have intensified, bringing rejuvenation closer to reality. Current strategies involve treatments using stem cells or their derivatives, such as the secretome. This article aims to highlight key points and evaluate the utilization of secretome derived from mesenchymal stromal cells (MSCs) as an antisenescent approach. Employing a quasi-systematic research approach, the authors conducted a comprehensive analysis based on a search algorithm targeting the in vitro effects of MSC-derived secretome on rescuing cells from a senescent state. Reviewing 39 articles out of 687 hits retrieved from PubMed and Scopus without a time limit, the authors synthesized information and identified common types of MSC-tissue sources utilized (including bone marrow-MSCs, umbilical cord-MSCs, iPSC-derived MSCs, adipose tissue-MSCs, dental pulp-MSCs, amniotic membrane-MSCs, placenta-MSCs, gingival-MSCs, urine-MSCs, and commercially available MSC lineages) from both human and other species (such as mice and rats). The authors also examined the forms of secretome tested (including conditioned media and extracellular vesicles), the cell types treated (MSCs or other cell types), methods/biomarkers of monitoring senescence/rejuvenation, and the mechanisms involved. Ultimately, this review underscores the proof-of-principle of the beneficial effects of MSC-derived secretome in reversing cellular senescence across various cell types. Such insights might aid the scientific community in designing improved in vitro and in vivo assays for future research and clinical validation of this promising cell-free therapy.

Therapeutic prospects of microRNAs derived from mesenchymal stem cell extracellular vesicles in rheumatoid arthritis: a comprehensive overview

Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by inflammatory joint damage. Recent studies have focused on the significance of microRNAs (miRNAs) in the pathogenesis of RA. Mesenchymal stem cells (MSCs) have emerged as a potential therapeutic option for RA based on their regenerative and immunomodulatory properties. MSCs release extracellular vesicles (EVs) containing miRNAs that can modulate immune and inflammatory responses. This article provides a comprehensive overview of the current evidence on the existence of various MSCs-derived miRNAs involved in the pathophysiology, characterization, and treatment of RA. An overview of the miRNA profiles in MSC-EVs is provided, along with an examination of their impact on various cell types implicated in RA pathogenesis, including synovial fibroblasts, macrophages, and T cells. Furthermore, the therapeutic capability of MSC-EVs for miRNA-based therapies in RA is discussed. In total, this review can present an extensive view of the complex interaction between EVs and MSC-derived miRNAs in RA and thus suggest valuable strategies for developing new therapeutic approaches to target this debilitating disease.

Engineered extracellular vesicles for tissue repair and regeneration

Extracellular vesicles (EVs) are heterogeneous membrane-like vesicles secreted by living cells that are involved in many physiological and pathological processes and act as intermediaries of intercellular communication and molecular transfer. Recent studies have shown that EVs from specific sources regulate tissue repair and regeneration by delivering proteins, lipids, and nucleic acids to target cells as signaling molecules. Nanotechnology breakthroughs have facilitated the development and exploration of engineered EVs for tissue repair. Enhancements through gene editing, surface modification, and content modification have further improved their therapeutic efficacy. This review summarizes the potential of EVs in tissue repair and regeneration, their mechanisms of action, and their research progress in regenerative medicine. This review highlights their design logic through typical examples and explores the development prospects of EVs in tissue repair. The aim of this review is to provide new insights into the design of EVs for tissue repair and regeneration applications, thereby expanding their use in regenerative medicine.

Zinc-based Polyoxometalate Nanozyme Functionalized Hydrogels for optimizing the Hyperglycemic-Immune Microenvironment to Promote Diabetic Wound Regeneration

BACKGROUND

In diabetic wounds, hyperglycemia-induced cytotoxicity and impaired immune microenvironment plasticity directly hinder the wound healing process. Regulation of the hyperglycemic microenvironment and remodeling of the immune microenvironment are crucial.

RESULTS

Here, we developed a nanozymatic functionalized regenerative microenvironmental regulator (AHAMA/CS-GOx@Zn-POM) for the effective repair of diabetic wounds. This novel construct integrated an aldehyde and methacrylic anhydride-modified hyaluronic acid hydrogel (AHAMA) and chitosan nanoparticles (CS NPs) encapsulating zinc-based polymetallic oxonate nanozyme (Zn-POM) and glucose oxidase (GOx), facilitating a sustained release of release of both enzymes. The GOx catalyzed glucose to gluconic acid and (H₂O₂), thereby alleviating the effects of the hyperglycemic microenvironment on wound healing. Zn-POM exhibited catalase and superoxide dismutase activities to scavenge reactive oxygen species and H₂O₂, a by-product of glucose degradation. Additionally, Zn-POM induced M1 macrophage reprogramming to the M2 phenotype by inhibiting the MAPK/IL-17 signaling diminishing pro-inflammatory cytokines, and upregulating the expression of anti-inflammatory mediators, thus remodeling the immune microenvironment and enhancing angiogenesis and collagen regeneration within wounds. In a rat diabetic wound model, the application of AHAMA/CS-GOx@Zn-POM enhanced neovascularization and collagen deposition, accelerating the wound healing process.

CONCLUSIONS

Therefore, the regenerative microenvironment regulator AHAMA/CS-GOx@Zn-POM can achieve the effective conversion of a pathological microenvironment to regenerative microenvironment through integrated control of the hyperglycemic-immune microenvironment, offering a novel strategy for the treatment of diabetic wounds.

The emerging modulators of non-coding RNAs in diabetic wound healing

Diabetic wound healing is a complex physiological process often hindered by the underlying metabolic dysfunctions associated with diabetes. Despite existing treatments, there remains a critical need to explore innovative therapeutic strategies to improve patient outcomes. This article comprehensively examines the roles of non-coding RNAs (ncRNAs), specifically microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), in regulating key phases of the wound healing process: inflammation, angiogenesis, re-epithelialization, and tissue remodeling. Through a deep review of current literature, we discuss recent discoveries of ncRNAs that have been shown to either promote or impair the wound healing process in diabetic wound healing, which were not covered in earlier reviews. This review highlights the specific mechanisms by which these ncRNAs impact cellular behaviors and pathways critical to each healing stage. Our findings indicate that understanding these recently identified ncRNAs provides new insights into their potential roles in diabetic wound healing, thereby contributing valuable knowledge for future research directions in this field.

Lubricin-Inspired Nanozymes Reconstruct Cartilage Lubrication System with an "In-Out" Strategy

Lubricin, secreted primarily by chondrocytes, plays a critical role in maintaining the function of the cartilage lubrication system. However, both external factors such as friction and internal factors like oxidative stress can disrupt this system, leading to osteoarthritis. Inspired by lubricin, a lubricating nanozyme, that is, Poly-2-acrylamide-2-methylpropanesulfonic acid sodium salt-grafted aminofullerene, is developed to restore the cartilage lubrication system using an "In-Out" strategy. The "Out" aspect involves reducing friction through a combination of hydration lubrication and ball-bearing lubrication. Simultaneously, the "In" aspect aims to mitigate oxidative stress by reducing free radical, increasing autophagy, and improving the mitochondrial respiratory chain. This results in reduced chondrocyte senescence and increased lubricin production, enhancing the natural lubrication ability of cartilage. Transcriptome sequencing and Western blot results demonstrate that it enhances the functionality of mitochondrial respiratory chain complexes I, III, and V, thereby improving mitochondrial function in chondrocytes. In vitro and in vivo experiments show that the lubricating nanozymes reduce cartilage wear, improve chondrocyte senescence, and mitigate oxidative stress damage, thereby mitigating the progression of osteoarthritis. These findings provide novel insights into treating diseases associated with oxidative stress and frictional damage, such as osteoarthritis, and set the stage for future research and development of therapeutic interventions.

Advanced meta-analysis on therapeutic strategies of mesenchymal derived exosome for diabetic chronic wound healing and tissue remodeling

BACKGROUND

Exosome (EXOs) are rapidly being identified as key mediators of cell-to-cell communication. They convey biologically active molecules to target cells, serve important roles in a range of physiological and pathological processes, and have enormous potential as novel therapeutic strategies.

METHODS

Preclinical research published between 2019 and 2023 provided the study's data searched on different medline search engine, and clinicaltrials.gov was searched for clinical data. These papers were chosen because they are relevant to the research of mesenchymal stem cell-derived exosomes (MSC-EXOs). Thematic synthesis and meta-analysis were used to perform the meta-analysis of diabetic wound healing.

RESULTS

For data extraction, a total of 18 preclinical and 4 clinical trials were selected. Preclinical investigations involving EXOs across various animal wound healing models showed promising potential for treatment. Specifically, following EXO treatment, there was a notable correlation with wound closure rates, with a pooled proportion of 46 % (95 % CI: 0.34; 0.59) and τ2 of 0.0593 after 3 ± 2 days, 54 % (95 % CI: 0.43; 0.65) and τ2 of 0.0465 after 7 ± 2 days, and 69 % (95 % CI: 0.62; 0.76) and τ2 of 0.0221 after 14 ± 2 days, with an egger's test p-value of <0.01. Further investigation into heterogeneity was conducted through subgroup analysis based on the source of EXO and the animal model utilized in the study.

CONCLUSIONS

EXOs are proving to be viable platforms for the treatment of a wide range of disorders in clinical trials. MSC-EXOs exhibited significant diabetic wound healing capabilities across diverse outcomes including wound closure, increase angiogenesis, immunomodulatory ability and skin regeneration with its typical structure and functions.

Exosomes and microRNAs: insights into their roles in thermal-induced skin injury, wound healing and scarring

A burn is a type of injury to the skin or other tissues caused by heat, chemicals, electricity, sunlight, or radiation. Burn injuries have been proven to have the potential for long-term detrimental effects on the human body. The conventional therapeutic approaches are not able to effectively and easily heal these burn wounds completely. The main potential drawbacks of these treatments include hypertrophic scarring, contracture, infection, necrosis, allergic reactions, prolonged healing times, and unsatisfactory cosmetic results. The existence of these drawbacks and limitations in current treatment approaches necessitates the need to search for and develop better, more efficient therapies. The regenerative potential of microRNAs (miRNAs) and the exosomal miRNAs derived from various cell types, especially stem cells, offer advantages that outweigh traditional burn wound healing treatment procedures. The use of multiple types of stem cells is gaining interest due to their improved healing efficiency for various applications. Stem cells have several key distinguishing characteristics, including the ability to promote more effective and rapid healing of burn wounds, reduced inflammation levels at the wound site, and less scar tissue formation and fibrosis. In this review, we have discussed the stages of wound healing, the role of exosomes and miRNAs in improving thermal-induced wounds, and the impact of miRNAs in preventing the formation of hypertrophic scars. Research studies, pre-clinical and clinical, on the use of different cell-derived exosomal miRNAs and miRNAs for the treatment of thermal burns have been documented from the year 2000 up to the current time. Studies show that the use of different cell-derived exosomal miRNAs and miRNAs can improve the healing of burn wounds. The migration of exosomal miRNAs to the site of a wound leads to inhibition of apoptosis, induction of autophagy, re-epithelialization, granulation, regeneration of skin appendages, and angiogenesis. In conclusion, this study underscores the importance of integrating miRNA and exosome research into treatment strategies for burn injuries, paving the way for novel therapeutic approaches that could significantly improve patient outcomes and recovery times.

Exosome-mimetic vesicles derived from fibroblasts carrying matrine for wound healing

Background

Chronic skin wounds are a leading cause of hospital admissions and reduced life expectancy among older people and individuals with diabetes. Delayed wound healing is often attributed to a series of cellular abnormalities. Matrine, a well-studied component found in Sophora flavescens, is recognized for its anti-inflammatory effects. However, its impact on wound healing still remains uncertain. This study aims to explore the potential of matrine in promoting wound healing.

Methods

In this study, we utilized gradient extrusion to produce fibroblast-derived exosome-mimetic vesicles as carriers for matrine (MHEM). MHEM were characterized using transmission electron microscopy and dynamic light scattering analysis. The therapeutic effect of MHEM in wound healing was explored in vitro and in vivo.

Results

Both matrine and MHEM enhanced the cellular activity as well as the migration of fibroblasts and keratinocytes. The potent anti-inflammatory effect of matrine diluted the inflammatory response in the vicinity of wounds. Furthermore, MHEM worked together to promote angiogenesis and the expression of transforming growth factor β and collagen I. MHEM contained growth factors of fibroblasts that regulated the functions of fibroblasts, keratinocytes and monocytes, which synergistically promoted wound healing with the anti-inflammatory effect of matrine.

Conclusions

MHEM showed enhanced therapeutic efficacy in the inflammatory microenvironment, for new tissue formation and angiogenesis of wound healing.

Nanoceria-Mediated Cyclosporin A Delivery for Dry Eye Disease Management through Modulating Immune-Epithelial Crosstalk

Dry eye disease (DED) affects a substantial worldwide population with increasing frequency. Current single-targeting DED management is severely hindered by the existence of an oxidative stress-inflammation vicious cycle and complicated intercellular crosstalk within the ocular microenvironment. Here, a nanozyme-based eye drop, namely nanoceria loading cyclosporin A (Cs@P/CeO2), is developed, which possesses long-term antioxidative and anti-inflammatory capacities due to its regenerative antioxidative activity and sustained release of cyclosporin A (CsA). In vitro studies showed that the dual-functional Cs@P/CeO2 not only inhibits cellular reactive oxygen species production, sequentially maintaining mitochondrial integrity, but also downregulates inflammatory processes and repolarizes macrophages. Moreover, using flow cytometric and single-cell sequencing data, the in vivo therapeutic effect of Cs@P/CeO2 was systemically demonstrated, which rebalances the immune-epithelial communication in the corneal microenvironment with less inflammatory macrophage polarization, restrained oxidative stress, and enhanced epithelium regeneration. Collectively, our data proved that the antioxidative and anti-inflammatory Cs@P/CeO2 may provide therapeutic insights into DED management.

Applications of Exosomal miRNAs from Mesenchymal Stem Cells as Skin Boosters

The skin is the outer layer of the human body, and it is crucial in defending against injuries and damage. The regenerative capacity of aging and damaged skin caused by exposure to external stimuli is significantly impaired. Currently, the rise in average life expectancy and the modern population's aesthetic standards have sparked a desire for stem-cell-based therapies that can address skin health conditions. In recent years, mesenchymal stem cells (MSCs) as therapeutic agents have provided a promising and effective alternative for managing skin regeneration and rejuvenation, attributing to their healing capacities that can be applied to damaged and aged skin. However, it has been established that the therapeutic effects of MSC may be primarily mediated by paracrine mechanisms, particularly the release of exosomes (Exos). Exosomes are nanoscale extracellular vesicles (EVs) that have lipid bilayer and membrane structures and can be naturally released by different types of cells. They influence the physiological and pathological processes of recipient cells by transferring a variety of bioactive molecules, including lipids, proteins, and nucleic acids such as messenger RNAs (mRNAs) and microRNAs (miRNAs) between cells, thus playing an important role in intercellular communication and activating signaling pathways in target cells. Among them, miRNAs, a type of endogenous regulatory non-coding RNA, are often incorporated into exosomes as important signaling molecules regulating protein biosynthesis. Emerging evidence suggests that exosomal miRNAs from MSC play a key role in skin regeneration and rejuvenation by targeting multiple genes and regulating various biological processes, such as participating in inflammatory responses, cell migration, proliferation, and apoptosis. In this review, we summarize the recent studies and observations on how MSC-derived exosomal miRNAs contribute to the regeneration and rejuvenation of skin tissue, with particular attention to the applications of bioengineering methods for manipulating the miRNA content of exosome cargo to improve their therapeutic potential. This review can provide new clues for the diagnosis and treatment of skin damage and aging, as well as assist investigators in exploring innovative therapeutic strategies for treating a multitude of skin problems with the aim of delaying skin aging, promoting skin regeneration, and maintaining healthy skin.

MiR-145-5p overexpression rejuvenates aged adipose stem cells and accelerates wound healing

Adipose-derived stem cells (ADSCs) have been widely applied in translational and regenerative medicine. During aging, there is a recognized functional decline in ADSCs, which compromises their therapeutic effectiveness. Currently, the mechanisms of aging-induced stem cell dysfunction remain unclear, hence there is a need to elucidate these mechanisms and propose strategies for reversing this functional impairment. In this study, we found that ADSCs isolated from old donors (O-ADSCs) presented inferior phenotypes and decreased miR-145-5p levels compared to those from young donors (Y-ADSCs). To interrogate the role of miR-145-5p in ADSCs, gain- and loss-of-function assays were performed. The results indicated that miR-145-5p overexpression in O-ADSCs promoted cellular proliferation and migration, while reducing cell senescence. Further study demonstrated that miR-145-5p could regulate ADSCs function by targeting bone morphogenetic protein binding endothelial cell precursor-derived regulator (BMPER), which is a crucial modulator in angiogenesis. Moreover, in vivo experiments showed that miR-145-5p-overexpressing O-ADSCs accelerated wound healing by promoting wound re-epithelialization and angiogenesis. Collectively, this study indicates that miR-145-5p works as a positive regulator for optimizing O-ADSCs function, and may be a novel therapeutic target for restoring aging-associated impairments in stem cell function.