Extracellular vesicles produced by human-induced pluripotent stem cell-derived endothelial cells can prevent arterial stenosis in mice via autophagy regulation

Effects of a PDGF-stem cell-hydrogel compound on skin wound healing in mice

BACKGROUND AIMS

The treatment of chronic refractory skin wounds still remains a serious clinical challenge. Stem cells and hydrogels are widely used in healing of skin wound of various types due to their superior bioactivities and biocompatibility. This study aimed to demonstrate the wound healing effect of a hydrogel compound loaded with enucleated stem cells expressing the platelet-derived growth factor (PDGF).

METHODS

An injectable hydrogel was formulated using 22% poloxamer 407, 1% poloxamer 188, and 1% hyaluronic acid. A PDGF-B transgenic cell line of mouse bone marrow mesenchymal stem cells (BMSCs) was generated by lentiviral infection. Cells were enucleated and embedded in hydrogel. The healing effects of the compound was tested in a full-thickness skin wound model of Balb/c mice. The wound models were randomly divided into four groups: the control group applied with PBS buffer; the hydrogel group with hydrogel only; the BMSC group with hydrogel mixed with normal BMSCs; and the BMSC-PDGF group with hydrogel mixed with enucleated BMSCs expressing PDGF.

RESULTS

Overexpression of PDGF-B in transgenic cell line of BMSCs was verified by RT-PCR, immunofluorescence staining and western blot. When enucleated, the viability measured by Calcein-AM staining reduced to 54.29% at 48 h. Conditioned medium was collected with or without hydrogel layered over cells. PDGF concentration measured by ELISA reached 14.66 ng/μL and 257.89 ng/μL respectively after 48-h cultivation, suggesting a possible slow releasing effect in the presence of hydrogel. When applied to the skin wound, the healing rates of the BMSC-PDGF group was significantly higher than that of the control group on day 3. BMSC-PDGF group had significantly more neovascularization and cutaneous appendages from day 7. The proliferation of collagen fibers in BMSC-PDGF group was significantly higher than the control group on day 3 and day 7. Finally, BMSC-PDGF group had significantly lower amount of the inflammatory factors TNF-α, IL-1β, IL-6, MMP-3 and MMP-9 than that of the control group on day 7.

CONCLUSIONS

PDGF-stem cell-hydrogel compound significantly improved wound healing and reduced wound inflammatory factor expression in Balb/c mice. This biomaterial-based approach provides a new powerful reference for the treatment of chronically wounded skin.

Hypoxia-regulated miR-103-3p/FGF2 axis in adipose-derived stem cells promotes angiogenesis by vascular endothelial cells during ischemic tissue repair

BACKGROUND

Identifying factors mediating adipose-derived stem cells (ADSCs)-induced endothelial cell angiogenesis in hypoxic skin flap tissue is critical for reconstruction. While the paracrine action of VEGF by adipose-derived stem cells (ADSCs) is established in promoting endothelial cell angiogenesis, the role of FGF2 and its regulatory mechanisms in ADSCs paracrine secretion remains unclear.

METHODS

We induced hypoxia and examined the expression level of FGF2 in ADSCs using ELISA, qRT-PCR, and western blotting. Proliferation of ADSCs under hypoxia was assessed using a CCK-8 assay. Co-culture experiments of hypoxia-induced ADSCs with vascular endothelial cells were conducted, and migration and tube formation abilities were evaluated through wound healing assays, transwell cell migration, and tube formation experiments.

RESULTS

Hypoxia treatment induced significant upregulation of FGF2 expression in ADSCs, along with enhanced cell proliferation. Co-culture of hypoxia-induced ADSCs with vascular endothelial cells showed increased migration and tube formation abilities of endothelial cells. Knockdown of FGF2 inhibited these processes, while overexpression of miR-103-3p mimics in ADSCs suppressed endothelial cell migration and tube formation. FGF2 is a direct target of miR-103-3p in ADSCs. miR-103-3p/FGF2 axis regulates ADSCs on the biological activity of co-cultured vascular endothelial cells. Moreover, in the ischemic skin flap nude mouse model, ADSCs injection showed increased blood vessel formation and reduced flap necrosis, with the most significant improvement observed with ADSCs of miR-103-3p inhibitor overexpressed.

CONCLUSION

Hypoxia induces paracrine secretion of FGF2 from ADSCs, which enhances endothelial cell angiogenesis. FGF2 expression is regulated by miR-103-3p in ADSCs. The miR-103-3p/FGF2 axis induces endothelial cell migration and angiogenesis and finally modulates ischemic skin flap repair in nude mice in vivo.

tsRNA-12391-Modified Adipose Mesenchymal Stem Cell-Derived Exosomes Mitigate Cartilage Degeneration in Osteoarthritis by Enhancing Mitophagy

Osteoarthritis (OA) is a cartilage-degenerative joint disease. Mitophagy impacts articular cartilage damage. tRNA-derived small RNAs (tsRNAs) are one of the contents of adipose mesenchymal stem cell (AMSC)-derived exosomes (AMSC-exos) and are involved in disease progression. However, whether tsRNAs regulate mitophagy and whether tsRNA-modified AMSC-exos improve OA via mitophagy remain unclear. We performed small RNA sequencing to identify OA-related tsRNAs, which were then loaded into AMSC-exos, exploring the function and mechanisms related to mitophagy in vitro and in vivo. Overall, 53 differentially expressed tsRNAs (DEtsRNAs) were identified between OA and normal cartilage tissues, among which 42 DEtsRNAs, including tsRNA-12391, were downregulated in the OA group. Target genes of tsRNA-12391 mainly participated in mitophagy-related pathways such as Rap1 signaling pathway. Compared to the control group, tsRNA-12391 mimics significantly promoted mitophagy, as shown by the upregulated expression of PINK1 and LC3 and the co-localization of Mito-Tracker Green and PINK1. Furthermore, tsRNA-12391 mimics effectively enhanced chondrogenesis in chondrocytes, as demonstrated by the elevated expression of collagen II and ACAN. AMSC-exos with tsRNA-12391 overexpression also facilitated mitophagy and chondrogenesis in vitro and in vivo. Mechanistically, tsRNA-12391 bound to ATAD3A restricted ATAD31 from degrading PINK1, leading to PINK1 accumulation. ATAD31 overexpression reversed the effects of tsRNA-12391 mimics on mitophagy and chondrogenesis. AMSC-exos loaded with tsRNA-12391 promoted mitophagy and chondrogenesis by interacting with ATAD31; this may be a novel therapeutic strategy for OA.

Adipose-derived exosomes as a preventative strategy against complications in hyaluronic acid filler applications: A comprehensive in vivo analysis

BACKGROUND

The aim of this study was to investigate the impact of exosomes derived from adipose-derived stem cells (ASCs) on complications arising from hyaluronic acid (HA) filler injections.

METHODS

An HA hydrogel blended with adipose stem cell-derived exosomes was prepared and administered to the inguinal fat pads of 16 C57BL/6J mice. The control group received only HA filler (HA group), and the study group was treated with a combination of HA filler and exosomes (exoHA group). Biopsy was performed 1 week and 1, 2, 3, and 6 months after the injections. The effects were assessed using hematoxylin and eosin and Masson's trichrome staining for histological examination, immunohistochemistry for collagen type I and Vascular Endothelial Growth Factor (VEGF), RNA sequencing, and quantitative real-time polymerase chain reaction (PCR) (Il6, Ifng, Hif1a, Acta2, Col1a1).

RESULTS

RNA sequencing revealed significant downregulation of the hypoxia (false discovery rate [FDR] q = 0.007), inflammatory response (FDR q = 0.009), TNFα signaling via NFκB (FDR q = 0.007), and IL6 JAK-STAT signaling (FDR q = 0.009) gene sets in the exoHA group. Quantitative PCR demonstrated a decrease in expression of proinflammatory cytokines (Il6, P < 0.05; Hif1a, P < 0.05) and fibrosis markers (Acta2, P < 0.05; Col1a1, P < 0.05) within the exoHA group, indicating reduced inflammation and fibrosis. Compared to the exoHA group, the HA group exhibited a thicker and more irregular capsules surrounding the HA filler after 6 months.

CONCLUSION

The addition of ASC-derived exosomes to HA fillers significantly reduces inflammation and accelerates collagen capsule maturation, indicating a promising strategy to mitigate the formation of HA filler-related nodules.

SIRT6 mitigates doxorubicin-induced cardiomyopathy via amelioration of mitochondrial dysfunction: A mechanistic study implicating the activation of the Nrf-2/FUNDC1 signaling axis

Doxorubicin-induced myocardial injury, characterized by myocardial hypertrophy and heart failure (HF), represents a primary contributor to end-stage cardiovascular mortality associated with anthracycline drugs. Prior research has elucidated that SIRT6-mediated oxidative processes and mitochondrial metabolic reprogramming are pivotal in sustaining energy metabolism during mitochondrial damage in cardiomyocytes. In the aftermath of doxorubicin-induced myocardial injury, myocardial hypertrophy and fibrosis exacerbate the impairment of cardiac ejection function, resulting in elevated myocardial oxygen consumption. This condition is accompanied by disrupted ATP production, diminished mitochondrial biogenesis, and inadequate synthesis of new mitochondrial DNA, collectively triggering necroptosis and apoptosis pathways. Our preliminary experimental results have confirmed that SIRT6, associated with traditional medicine, exerts cardioprotective effects. Nevertheless, the interaction between SIRT6 and Nrf-2-mediated mitochondrial biogenesis in the context of doxorubicin-induced HF and myocardial hypertrophy remains inadequately understood. The generation of mitochondria is a key mechanism that is involved in DNA repair and cell cycle management.

Porcine pericardial decellularized matrix bilayer patch containing adipose stem cell-derived exosomes for the treatment of diabetic wounds

Chronic hard-to-heal wounds pose a significant threat to patients' health and quality of life, and their clinical management remains a challenge. Adipose-derived stem cell exosomes (ADSC-exos) have shown promising results in promoting diabetic wound healing. However, effectively enhancing the retention of exosomes in wounds for treatment remains a key issue that needs to be addressed. There is a pressing need to develop new materials or methods to improve the bioavailability of exosomes. Porcine pericardium, an extracellular matrix-rich tissue, is easily obtainable and widely available. Decellularized porcine pericardium removes cellular components while retaining an extracellular matrix that supports cellular growth, making it an ideal raw material for preparing wound dressings. In this study, we developed porcine pericardial decellularized matrix bilayer patches loaded with ADSC-exos, which were transplanted into diabetic mouse skin wounds. Histological and immunohistochemical analyses revealed that these bilayer matrix patches accelerate wound healing by promoting granulation tissue formation, re-epithelialization, stimulating vascularization, and enhancing collagen production. In terms of the underlying biological mechanism, we found that decellularized extracellular matrix bilayer patches loaded with ADSC-exos enhanced the proliferation and migration of human dermal fibroblasts (HDFs) and HaCaT cells in vitro, and promoted tube formation in human umbilical vein endothelial cells (HUVECs). This research demonstrated that the porcine pericardial decellularized matrix is well-suited for exosome delivery and that these bilayer patches hold great potential in promoting diabetic wound healing, providing evidence to support the future clinical application of ADSC-exos.

Current advances in human-induced pluripotent stem cell-based models and therapeutic approaches for congenital heart disease

Congenital heart disease (CHD) represents a significant risk factor with profound implications for neonatal survival rates and the overall well-being of adult patients. The emergence of induced pluripotent stem cells (iPSCs) and their derived cells, combined with CRISPR technology, high-throughput experimental techniques, and organoid technology, which are better suited to contemporary research demands, offer new possibilities for treating CHD. Prior investigations have indicated that the paracrine effect of exosomes may hold potential solutions for therapeutic intervention. This review provides a summary of the advancements in iPSC-based models and clinical trials associated with CHD while elucidating potential therapeutic mechanisms and delineating clinical constraints pertinent to iPSC-based therapy, thereby offering valuable insights for further deliberation.

Engineering exosomes from fibroblast growth factor 1 pre-conditioned adipose-derived stem cells promote ischemic skin flaps survival by activating autophagy

Background

The recovery of ischemic skin flaps is a major concern in clinical settings. The purpose of this study is to evaluate the effects of engineered exosomes derived from FGF1 pre-conditioned adipose-derived stem cells (FEXO) on ischemic skin flaps.

Method

6 patients who suffered from pressure ulcer at stage 4 and underwent skin flaps surgery were recruited in this study to screen the potential targets of ischemic skin flaps in FGF family. FGF1 was co-incubated with adipose stem cells, and ultracentrifugation was applied to extract FEXO. Transcriptome sequencing analysis was used to determine the most effective microRNA in FEXO. Animal skin flaps models were established in our study to verify the effects of FEXO. Immunofluorescence (IF), western blotting (WB) and other molecular strategy were used to evaluate the effects and mechanism of FEXO.

Results

FGF1 was expected to be the therapeutic and diagnostic target of ischemic skin flaps, but there is still some deficiency in rescuing skin flaps. FEXO significantly improved the viability of RPSFs and endothelial cells by inhibiting oxidative stress and alleviating apoptosis and pyroptosis through augmenting autophagy flux. In addition, FEXO inhibited the over-activated inflammation responses. Transcriptome sequencing analysis showed that miR-183-5p was significantly elevated in FEXO, and inhibiting miR-183-5p resulted in impaired protective effects of autophagy in skin flaps. The exosomal miR-183-5p markedly enhanced cell viability, inhibited oxidative stress and alleviated apoptosis and pyroptosis in endothelial cells by targeting GPR137 through Pi3k/Akt/mTOR pathway, indicating that GPR137 could also be a therapeutic target of ischemic skin flap. It was also notabale that FGF1 increased the number of exosomes by upregulating VAMP3, which may be a promising strategy for clinical translation.

Conclusion

FEXO markedly improved the survivial rate of ischemic skin flaps through miR-183-5p/GPR137/Pi3k/Akt/mTOR axis, which would be a promising strategy to rescue ischemic skin flaps.

Exosomes from mesenchymal stem cells: Potential applications in wound healing

Wound healing is a continuous and complex process regulated by multiple factors, which has become an intractable clinical burden. Mesenchymal stem cell-derived exosomes (MSC-exos) possess low immunogenicity, easy preservation, and potent bioactivity, which is a mirror to their parental cells MSC-exos are important tools for regulating the biological behaviors of wound healing-associated cells, including fibroblasts, keratinocytes, immune cells, and endothelial cells. MSC-exos accelerate the wound healing process at cellular and animal levels by modulating inflammatory responses, promoting collagen deposition and vascularization. MSC-exos accelerate wound healing at the cellular and animal levels by modulating inflammatory responses and promoting collagen deposition and vascularization. This review summarizes the roles and mechanisms of MSC-exos originating from various sources in promoting the healing efficacy of general wounds, diabetic wounds, burn wounds, and healing-related scars. It also discusses the limitations and perspectives of MSC-exos in wound healing, in terms of exosome acquisition, mechanistic complexity, and exosome potentiation modalities. A deeper understanding of the properties and functions of MSC-exos is beneficial to advance the therapeutic approaches for achieving optimal wound healing.

High-Throughput Screening of an FDA-Approved Compound Library Reveals a Novel GAS6 Receptor Agonist for Therapeutic Intervention in Septic Myocardial and microvascular Injury via Modulation of Danger-Associated Molecular Patterns

PGAM5 and VDAC1 have both been reported to regulate mitophagy. However, the mechanisms by which they regulate sepsis-induced inflammatory microvascular injury remain unverified. In previous studies, we established the role of this regulatory axis in various phenotypic processes, including mitophagy, mitochondrial biogenesis, the mitochondrial unfolded protein response, and mitochondrial dynamics, while further confirming the interactive regulatory proteins within this axis. However, the validation and elucidation of these regulatory phenotypes have primarily focused on ischemic heart diseases such as ischemic myocardial injury and heart failure. Sepsis-related myocardial injury is currently recognized as a significant cardiac impairment, and although there are cardioprotective and nutritional agents available for supportive therapy, fundamental research validating the upstream targets and mechanisms of microvascular injury is still lacking. Based on our previous research, we further explored the role of mitophagy dysfunction mediated by VDAC1 and its upstream regulatory protein PGAM5 in sepsis-induced coronary microvascular injury. We also confirmed the material basis and metabolic pathway regulation targeting the PGAM5- VDAC1 interactive mechanism with relevant drugs. Our findings suggest that PGAM5-mediated mitophagy dysfunction may be a crucial factor leading to sepsis-induced microvascular injury, primarily interacting with VDAC1-mediated mitochondrial membrane dysfunction. Animal experiments revealed that cardiac-specific knockout of PGAM5 could reverse LPS-induced coronary microvascular injury and inflammatory damage, restoring cardiac ejection function and mitophagy functionality. In vitro studies also confirmed that the PGAM5-VDAC1 interaction can normalize mitophagy, restoring the normal morphology and structure of mitochondria while maintaining normal mitochondrial energy metabolism levels and respiratory chain function. Further pharmacological research indicated that the active ingredients of traditional Chinese medicine-Puerarin (TCM, a GAS6 Receptor Agonist) can target the PGAM5- VDAC1 axis to regulate mitophagy and inhibit LPS-induced necrotic apoptosis in cardiomyocytes, potentially reversing mitochondrial pathway-related cardiac injury. TCM may emerge as a prospective therapeutic agent targeting the PGAM5- VDAC1 axis.

Exosomes Derived from Antler Mesenchymal Stem Cells Promote Wound Healing by miR-21-5p/STAT3 Axis

Background

Deer antlers, unique among mammalian organs for their ability to regenerate annually without scar formation, provide an innovative model for regenerative medicine. This study explored the potential of exosomes derived from antler mesenchymal stem cells (AMSC-Exo) to enhance skin wound healing.

Methods

We explored the proliferation, migration and angiogenesis effects of AMSC-Exo on HaCaT cells and HUVEC cells. To investigate the skin repairing effect of AMSC-Exo, we established a full-thickness skin injury mouse model. Then the skin thickness, the epidermis, collagen fibers, CD31 and collagen expressions were tested by H&E staining, Masson's trichrome staining and immunofluorescence experiments. MiRNA omics analysis was conducted to explore the mechanism of AMSC-Exo in skin repairing.

Results

AMSC-Exo stimulated the proliferation and migration of HaCaT cells, accelerated the migration and angiogenesis of HUVEC cells. In the mouse skin injury model, AMSC-Exo stimulated angiogenesis and regulated the extracellular matrix by facilitating the conversion of collagen type III to collagen type I, restoring epidermal thickness to normal state without aberrant hyperplasia. Notably, AMSC-Exo enhanced the quality of wound healing with increased vascularization and reduced scar formation. MiRNAs in AMSC-Exo, especially through the miR-21-5p/STAT3 signaling pathway, played a crucial role in these processes.

Conclusion

This study underscores the efficacy of AMSC-Exo in treating skin wounds, suggesting a new approach for enhancing skin repair and regeneration.

LncRNA AGAP2-AS1 stabilizes ATG9A to promote autophagy in endothelial cells - Implications for burn wound healing

Deep second- or mixed-degree burn lesions are difficult to heal due to the impaired dermis supporting of epidermis renewal and nutrition delivery. Early dermis debridement and preservation speed healing and enhance results, emphasizing the need of knowing processes that promote burn-denatured dermis recovery, notably endothelial cell angiogenesis and autophagy. Integrative bioinformatics investigations identified AGAP2-AS1 as a highly elevated lncRNA in burn tissues. Pearson's correlation study connected AGAP2-AS1 to 112 differently co-expressed protein-coding genes involved in burn healing processes such cell cycle and TGF-beta receptor signaling. Experimental validation showed that heat damage elevated AGAP2-AS1 in HUVECs and HDMECs. Functionally, AGAP2-AS1 overexpression in heat-denatured HUVECs and HDMECs increased cell survival, migration, invasion, and angiogenesis. In addition, AGAP2-AS1 overexpression increased endothelial cell autophagy. Additional investigation showed AGAP2-AS1's association with ATG9A, stabilizing it. Post-heat damage, ATG9A knockdown drastically reduced HUVEC and HDMEC survival, migration, invasion, angiogenesis, and autophagy. More notably, ATG9A knockdown drastically reduced the benefits of AGAP2-AS1 overexpression on endothelial cell functions and autophagy. The positive association between AGAP2-AS1 and ATG9A expression in burn tissue samples highlights their crucial roles in endothelial cell response to heat injury, indicating that targeting this axis may aid burn wound healing. The research found that lncRNA AGAP2-AS1 stabilizes ATG9A and promotes autophagy in endothelial cells. These results imply that targeting the AGAP2-AS1/ATG9A axis may improve angiogenesis and tissue regeneration in burn injuries, revealing burn wound healing molecular pathways.

Global trends in the clinical utilization of exosomes in dermatology: a bibliometric analysis

The arena of exosomal research presents substantial emerging prospects for clinical dermatology applications. This investigation conducts a thorough analysis of the contemporary global research landscape regarding exosomes and their implications for dermatological applications over the preceding decade. Employing bibliometric methodologies, this study meticulously dissects the knowledge framework and identifies dynamic trends within this specialized field. Contemporary scholarly literature spanning the last decade was sourced from the Web of Science Core Collection (WoSCC) database. Subsequent to retrieval, both quantitative and visual analyses of the pertinent publications were performed utilizing the analytical software tools VOSviewer and Citespace. A comprehensive retrieval yielded 545 scholarly articles dated from January 1, 2014, to December 31, 2023. Leading the research forefront are institutions such as Shanghai Jiao Tong University, The Fourth Military Medical University, and Sun Yat-sen University. The most prolific contributors on a national scale are China, the United States, and South Korea. Among the authors, Zhang Bin, Zhang Wei, and Zhang Yan emerge as the most published, with Zhang Bin also achieving the distinction of being the most cited. The International Journal of Molecular Sciences leads in article publications, whereas Stem Cell Research & Therapy holds the pinnacle in citation rankings. Theranostics boasts the highest impact factor among the periodicals. Current research hotspots in this area include Adipose mesenchymal stem cell-derived exosomes(ADSC-Exos), diabetic skin wounds, cutaneous angiogenesis, and the combination of biomaterials and exosomes. This manuscript constitutes the inaugural comprehensive bibliometric analysis that delineates the prevailing research trends and advancements in the clinical application of exosomes in dermatology. These analyses illuminate the contemporary research focal points and trajectories, providing invaluable insights that will inform further exploration within this domain.

The Chemopreventive Impact of Diet-Derived Phytochemicals on the Adipose Tissue and Breast Tumor Microenvironment Secretome

Cancer cells-derived extracellular vesicles can trigger the transformation of adipose-derived mesenchymal stem cells (ADMSC) into a pro-inflammatory, cancer-associated adipocyte (CAA) phenotype. Such secretome-mediated crosstalk between the adipose tissue and the tumor microenvironment (TME) therefore impacts tumor progression and metastatic processes. In addition, emerging roles of diet-derived phytochemicals, especially epigallocatechin-3-gallate (EGCG) among other polyphenols, in modulating exosome-mediated metabolic and inflammatory signaling pathways have been highlighted. Here, we discuss how selected diet-derived phytochemicals could alter the secretome signature as well as the crosstalk dynamics between the adipose tissue and the TME, with a focus on breast cancer. Their broader implication in the chemoprevention of obesity-related cancers is also discussed.

miR-29b-triggered epigenetic regulation of cardiotoxicity following exposure to deltamethrin in zebrafish

Deltamethrin is a classical pyrethroid insecticide that is frequently detected in aquatic environments and organisms. Furthermore, deltamethrin has been detected in samples related to human health and is a potential risk to public health. This study aimed to investigate the mechanism of cardiotoxicity induced by deltamethrin. Zebrafish were exposed to 0.005, 0.05, or 0.5 μg/L deltamethrin for 28 days. The results showed a significant reduction in male reproduction compared to female reproduction. Additionally, the heart rate decreased by 15.75 % in F1 after parental exposure to 0.5 μg/L deltamethrin. To evaluate cardiotoxicity, deltamethrin was administered to the zebrafish embryos. By using miRNA-Seq and bioinformatics analysis, it was discovered that miR-29b functions as a toxic regulator by targeting dnmts. The overexpression of miR-29b and inhibition of dnmts resulted in cardiac abnormalities, such as pericardial edema, bradycardia, and abnormal expression of genes related to the heart. Similar changes in the levels of miR-29b and dnmts were also detected in the gonads of F0 males and F1 embryos, confirming their effects. Overall, the results suggest that deltamethrin may have adverse effects on heart development in early-stage zebrafish and on reproduction in adult zebrafish. Furthermore, epigenetic modifications may threaten the cardiac function of offspring.

Adipose-Derived Stem Cell Exosomes Facilitate Diabetic Wound Healing: Mechanisms and Potential Applications

Wound healing in diabetic patients is frequently hampered. Adipose-derived stem cell exosomes (ADSC-eoxs), serving as a crucial mode of intercellular communication, exhibit promising therapeutic roles in facilitating wound healing. This review aims to comprehensively outline the molecular mechanisms through which ADSC-eoxs enhance diabetic wound healing. We emphasize the biologically active molecules released by these exosomes and their involvement in signaling pathways associated with inflammation modulation, cellular proliferation, vascular neogenesis, and other pertinent processes. Additionally, the clinical application prospects of the reported ADSC-eoxs are also deliberated. A thorough understanding of these molecular mechanisms and potential applications is anticipated to furnish a theoretical groundwork for combating diabetic wound healing.

Current landscape of exosomes in tuberculosis development, diagnosis, and treatment applications

Tuberculosis (TB), caused by the bacterial pathogen Mycobacterium tuberculosis (MTB), remains one of the most prevalent and deadly infectious diseases worldwide. Currently, there are complex interactions between host cells and pathogens in TB. The onset, progression, and regression of TB are correlated not only with the virulence of MTB but also with the immunity of TB patients. Exosomes are cell-secreted membrane-bound nanovesicles with lipid bilayers that contain a variety of biomolecules, such as metabolites, lipids, proteins, and nucleic acids. Exosome-mediated cell-cell communication and interactions with the microenvironment represent crucial mechanisms through which exosomes exert their functional effects. Exosomes harbor a wide range of regulatory roles in physiological and pathological conditions, including MTB infection. Exosomes can regulate the immune response, metabolism, and cellular death to remodel the progression of MTB infection. During MTB infection, exosomes display distinctive profiles and quantities that may act as diagnostic biomarkers, suggesting that exosomes provide a revealing glimpse into the evolving landscape of MTB infections. Furthermore, exosomes derived from MTB and mesenchymal stem cells can be harnessed as vaccine platforms and drug delivery vehicles for the precise targeting and treatment of TB. In this review, we highlight the functions and mechanisms through which exosomes influence the progression of TB. Additionally, we unravel the critical significance of exosomal constituents in the diagnosis and therapeutic applications of TB, aiming to offer novel perspectives and strategies for combating TB.

Exosomes from umbilical cord-derived mesenchymal stem cells combined with gelatin methacryloyl inhibit vein graft restenosis by enhancing endothelial functions

BACKGROUND

The prevalence of coronary artery disease is increasing. As a common treatment method, coronary artery bypass transplantation surgery can improve heart problems while also causing corresponding complications. Venous graft restenosis is one of the most critical and intractable complications. Stem cell-derived exosomes could have therapeutic promise and value. However, as exosomes alone are prone to inactivation and easy removal, this therapeutic method has not been widely used in clinical practice. Methacrylated gelatin (GelMA) is a polymer with a loose porous structure that maintains the biological activity of the exosome and can control its slow release in vivo. In this study, we combined human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-Exos) and GelMA to explore their effects and underlying mechanisms in inhibiting venous graft restenosis.

RESULTS

Human umbilical cord mesenchymal stem cells (hUCMSCs) were appraised using flow cytometry. hUCMSC-Exos were evaluated via transmission electron microscopy and western blotting. hUCMSC-Exos embedded in a photosensitive GelMA hydrogel (GelMA-Exos) were applied topically around venous grafts in a rat model of cervical arteriovenous transplantation, and their effects on graft reendothelialization and restenosis were evaluated through ultrasonic, histological, and immunofluorescence examinations. Additionally, we analyzed the material properties, cellular reactions, and biocompatibility of the hydrogels. We further demonstrated that the topical application of GelMA-Exos could accelerate reendothelialization after autologous vein transplantation and reduce restenosis in the rat model. Notably, GelMA-Exos caused neither damage to major organs in mice nor excessive immune rejection. The uptake of GelMA-Exos by endothelial cells stimulated cell proliferation and migration in vitro. A bioinformatic analysis of existing databases revealed that various cell proliferation and apoptosis pathways, including the mammalian target of rapamycin (mTOR)-phosphoinositide 3-kinase (PI3K)-AKT signaling pathways, might participate in the underlying regulatory mechanism.

CONCLUSIONS

Compared with the tail vein injection of hUCMSC-Exos, the local application of a mixture of hUCMSC-Exos and GelMA was more effective in promoting endothelial repair of the vein graft and inhibiting restenosis. Therefore, the proposed biomaterial-based therapeutic approach is a promising treatment for venous graft restenosis.

Multi-Omics Profiling of Human Endothelial Cells from the Coronary Artery and Internal Thoracic Artery Reveals Molecular but Not Functional Heterogeneity

Major adverse cardiovascular events occurring upon coronary artery bypass graft surgery are typically accompanied by endothelial dysfunction. Total arterial revascularisation, which employs both left and right internal thoracic arteries instead of the saphenous vein to create a bypass, is associated with better mid- and long-term outcomes. We suggested that molecular profiles of human coronary artery endothelial cells (HCAECs) and human internal mammary artery endothelial cells (HITAECs) are coherent in terms of transcriptomic and proteomic signatures, which were then investigated by RNA sequencing and ultra-high performance liquid chromatography-mass spectrometry, respectively. Both HCAECs and HITAECs overexpressed molecules responsible for the synthesis of extracellular matrix (ECM) components, basement membrane assembly, cell-ECM adhesion, organisation of intercellular junctions, and secretion of extracellular vesicles. HCAECs were characterised by higher enrichment with molecular signatures of basement membrane construction, collagen biosynthesis and folding, and formation of intercellular junctions, whilst HITAECs were notable for augmented pro-inflammatory signaling, intensive synthesis of proteins and nitrogen compounds, and enhanced ribosome biogenesis. Despite HCAECs and HITAECs showing a certain degree of molecular heterogeneity, no specific markers at the protein level have been identified. Coherence of differentially expressed molecular categories in HCAECs and HITAECs suggests synergistic interactions between these ECs in a bypass surgery scenario.