The miR-590-3p/VEGFA axis modulates secretion of VEGFA from adipose-derived stem cells, which acts as a paracrine regulator of human dermal microvascular endothelial cell angiogenesis

Enhancing Fat Transplantation Efficiency in a Mouse Model through Pretreatment of Adipose-Derived Stem Cells with RIP3 Inhibitors

BACKGROUND

Autologous fat transplantation, widely used in cosmetic and reparative surgery for volumetric enhancements, faces challenges with its inconsistent long-term survival rates. The technique's efficacy, crucial for its development, is hindered by unpredictable outcomes. Enriching fat grafts with adipose-derived stem cells (ADSCs) shows promise in improving survival efficiency.

OBJECTIVES

This study aimed to explore the potential of receptor-interacting protein kinase 3 (RIP3) kinase inhibitors as a pretreatment for ADSCs in enhancing autologous fat graft retention over a long term.

METHODS

ADSCs were isolated, cultured under normal or oxygen-glucose deprivation conditions, and mixed with particulate fat grafts to form distinct experimental groups in female nude mice. Fat graft mass and volume, along with underlying mechanisms, were evaluated using quantitative reverse transcription polymerase chain reaction (RT-qPCR), immunohistochemistry, and Western blot analysis.

RESULTS

The experimental group, pretreated with RIP3 kinase inhibitors, had higher graft mass and volume, greater adipocyte integrity, and increased peroxisome proliferator-activated receptor gamma (PPARγ) mRNA levels than control groups. Furthermore, the experimental group demonstrated lower expression of necroptosis pathway proteins in the short term and an ameliorated inflammatory response as indicated by interleukin-1 beta (IL-1β), interleukin-10 (IL-10) mRNA levels, and histological analyses. Notably, enhanced neovascularization was evident in the experimental group.

CONCLUSIONS

These findings suggest that RIP3 kinase inhibitor pretreatment of ADSCs can improve fat graft survival, promote adipocyte integrity, potentially decrease inflammation, and enhance neovascularization.

NO LEVEL ASSIGNED

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The optimized priming effect of FGF-1 and FGF-2 enhances preadipocyte lineage commitment in human adipose-derived mesenchymal stem cells

The cell-assisted lipotransfer technique, integrating adipose-derived mesenchymal stem cells (ADMSCs), has transformed lipofilling, enhancing fat graft viability. However, the multipotent nature of ADMSCs poses challenges. To improve safety and graft vitality and to reduce unwanted lineage differentiation, this study refines the methodology by priming ADMSCs into preadipocytes-unipotent, self-renewing cells. We explored the impact of fibroblast growth factor-1 (FGF-1), fibroblast growth factor-2 (FGF-2), and epidermal growth factor (EGF), either alone or in combination, on primary human ADMSCs during the proliferative phase. FGF-2 emerged as a robust stimulator of cell proliferation, preserving stemness markers, especially when combined with EGF. Conversely, FGF-1, while not significantly affecting cell growth, influenced cell morphology, transitioning cells to a rounded shape with reduced CD34 expression. Furthermore, co-priming with FGF-1 and FGF-2 enhanced adipogenic potential, limiting osteogenic and chondrogenic tendencies, and possibly promoting preadipocyte commitment. These preadipocytes exhibited unique features: rounded morphology, reduced CD34, decreased preadipocyte factor 1 (Pref-1), and elevated C/EBPα and PPARγ, alongside sustained stemness markers (CD73, CD90, CD105). Mechanistically, FGF-1 and FGF-2 activated key adipogenic transcription factors-C/EBPα and PPARγ-while inhibiting GATA3 and Notch3, which are adipogenesis inhibitors. These findings hold the potential to advance innovative strategies for ADMSC-mediated lipofilling procedures.

Delivery of microRNA-423-5p by exosome from adipose-derived stem/stromal cells inhibits DVL3 to potentiate autologous fat graft survival through adipogenesis and inflammatory response

Autologous fat grafting represents a reconstructive technique but is limited by unstable graft retention. Based on existing reports and bioinformatics prediction, we hypothesized that delivering exosomes from human adipose-derived stem/stromal cells (hADSC-Exo) would increase fat graft survival and further explore the mechanism. hADSC-Exo were extracted and identified. An autologous fat grafting model was established using donor and recipient mice, followed by hADSC-Exo treatment. hADSC-Exo promoted the retention of autologous fat grafts in mice, along with increased adipocyte activity, angiogenesis, and decreased inflammation in grafts. Moreover, hADSC-Exo potentiated the adipose differentiation of 3T3-L1 cells, enhanced the angiogenic and migratory capacity of human umbilical vein endothelial cells, and inhibited the inflammation and viability of RAW 264.7 cells. The therapeutic effect of hADSC-Exo on fat grafting was associated with the delivery of microRNA (miR)-423-5p. Deletion of miR-423-5p in Exo impaired the function of hADSC-Exo on fat retention. miR-423-5p bound to DVL3 to suppress DVL3 expression, and DVL3 deletion promoted adipose differentiation of 3T3-L1 cells. In conclusion, our findings further widen the theoretical basis of the clinical application of hADSC-Exo in autologous fat grafts.

Adipose stem cells in tissue regeneration and repair: From bench to bedside

ADSCs are a large number of mesenchymal stem cells in Adipose tissue, which can be applied to tissue engineering. ADSCs have the potential of multi-directional differentiation, and can differentiate into bone tissue, cardiac tissue, urothelial cells, skin tissue, etc. Compared with other mesenchymal stem cells, ADSCs have a multitude of promising advantages, such as abundant number, accessibility in cell culture, stable function, and less immune rejection. There are two main methods to use ADSCs for tissue repair and regeneration. One is to implant the "ADSCs-scaffold composite" into the injured site to promote tissue regeneration. The other is cell-free therapy: using ADSC-exos or ADSC-CM alone to release a large number of miRNAs, cytokines and other bioactive substances to promote tissue regeneration. The tissue regeneration potential of ADSCs is regulated by a variety of cytokines, signaling molecules, and external environment. The differentiation of ADSCs into different tissues is also induced by growth factors, ions, hormones, scaffold materials, physical stimulation, and other factors. The specific mechanisms are complex, and most of the signaling pathways need to be further explored. This article reviews and summarizes the mechanism and clinical application of ADSCs in tissue injury repair so far, and puts forward further problems that need to be solved in this field, hoping to provide directions for further research in this field.

Integrated network pharmacology to investigate the mechanism of Salvia miltiorrhiza Bunge in the treatment of myocardial infarction

Salvia miltiorrhiza Bunge is a natural drug for treating myocardial infarction (MI). However, the targets and mechanisms of S. miltiorrhiza Bunge in the treatment of MI are yet to be elucidated. Traditional Chinese medicine systems pharmacology (TCMSP) data were used to screen out chemical constituents, and UniProt was used to predict relevant targets. Disease targets were obtained from the Online Mendelian Inheritance in Man and GeneCards databases. We used the STRING platform to build a protein-protein interaction network and used Cytoscape_v3.8.1 software to make a Drug-Ingredients-Gene Symbols-Disease network map. The Metascape database was used to perform gene ontology and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analyses for drug-disease overlapping gene symbols. The targets identified by network pharmacology were further verified by in vitro and in vivo experiments. Seventy-five active components of S. miltiorrhiza Bunge were obtained from the TCMSP database, while 370 disease targets and 29 cross-targets were obtained from the Genecards database. The KEGG pathway enrichment results suggested that the mechanism of S. miltiorrhiza Bunge in the treatment of MI was significantly related to the VEGF signalling pathway. In vitro and in vivo experiments were used to evaluate the reliability of some important active ingredients and targets. S. miltiorrhiza Bunge alleviated the damage to cardiac function, attenuated myocardial fibrosis and protected endothelial cell function by increasing the expression of TGF-β and VEGFA. S. miltiorrhiza Bunge showed the therapeutic effect of MI by promoting the expression of VEGFA signalling pathway, providing a reliable basis for exploring herbal treatment of MI.

Hypoxia-induced CCL2/CCR2 axis in adipose-derived stem cells (ADSCs) promotes angiogenesis by human dermal microvascular endothelial cells (HDMECs) in flap tissues

Flap expansion has become an important method widely used in wound repair and organ reconstruction. However, distal skin flap ischemic necrosis remains a problematic complication. In this study, integrative bioinformatics analyses indicated the upregulation of C-C motif chemokine ligand 2 (CCL2) and C-C motif chemokine receptor 2 (CCR2) in reperfusion-exposed skin flap tissues. In adipose-derived stem cells (ADSCs, CD90-positive, CD29-positive, CD34-negative, and CD106-negative) exposed to hypoxia, HIF-1α and CCL2 levels were significantly elevated. Conditioned medium (CM) from hypoxia-stimulated ADSCs promoted HDMEC proliferation, migration, and tube formation, partially inhibited by sh-CCL2-induced CCL2 knockdown or neutralized antibody-induced CCL2 depletion in ADSCs. Consistently, CCL2, CCR2, TNF-α, TLR2, and TLR4 protein levels in HDMECs were significantly increased by hypoxia-treated ADSCs CM, and partially decreased by sh-CCL2-induced CCL2 knockdown or neutralizing antibody-induced CCL2 knockdown in ADSCs. In the flap expansion model, ADSCs transplantation significantly improved flap survival and angiogenesis by endothelial cells in flap tissues, whereas CCL2 knockdown in ADSCs partially eliminated the improvement by ADSCs transplantation; overexpression of CCL2 in ADSCs further promoted the effects of ADSCs transplantation on skin flap. In conclusion, the CCL2/CCR2 axis in ADSCs could be induced by hypoxia, promoting HDMEC proliferation, migration, and tube formation and improving flap survival and angiogenesis in flap tissues.

Sustainable Production and Activity Determination of Serum-Free Conditioned Medium from Menstrual Blood-Derived Endometrial Stem Cells

Mesenchymal stem cells (MSCs) have exhibited great potential as a regenerative medicine, and MSC-derived paracrine effects, mainly including the secretion of various bioactive factors, play critical roles in MSC-based therapies. MSC-derived serum-free conditioned medium (MSC-CM) is defined as the secretome of MSC-derived bioactive factors and is considered a new cell-free therapeutic agent for disease treatment. However, the MSC-CM used in previous studies was prepared by a nearly disposable method that the MSCs were discarded after preparing MSC-CM, and the preparation time was variable; simultaneously, the viability changes of MSCs after MSC-CM preparation are still unknown. Therefore, this study takes MenSCs as a research project and aims to explore the suitable period of sustainable MenSC-CM preparation rather than using a disposable method. As expected, our results confirmed that MenSC-CM improves viability of both naïve targeted cells and H₂O₂-injured targeted cells, and suggested that 36 h is suitable for sustainable MenSC-CM preparation in which the angiogenic factors almost reach to the peak. Simultaneously, the MenSCs used to prepare the MenSC-CM for 36 h also maintained preferable cell viability and could be sustainably used for further MenSC-CM preparation. Moreover, the in vivo results further confirmed the improvement of MenSC-CM on promoting skin wound healing. Consequently, our results not only provide support for optimizing MSC-CM sustainable preparation based on various MSCs but also promote the comprehensive application of MenSCs in the clinic.

MiR-590-3p affects the function of adipose-derived stem cells (ADSCs) on the survival of skin flaps by targeting VEGFA

Introduction

Partial necrosis of skin flaps is still a substantial problem in plastic and reconstructive surgery. In this study, the role of miR-590-3p in adipose-derived stem cells (ADSCs) transplantation in improving the survival of skin flap in a mouse model was delved into.

Method

An abdominal perforator flap model was established in mice. The histopathological examination of mice skin tissues after ADSCs transplantation was implemented using Hematoxylin & eosin (H&E) staining. Immunohistochemistry (IHC) or immunofluorescence (IF) staining was utilized to assess the PCNA or CD31 levels. The concentrations of VEGFA in the culture medium were quantified using a VEGFA ELISA kit.

Result

The damage of tissue in the skin flap was dramatically relieved by ADSCs transplantation. MiR-590-3p overexpression notably suppressed, while miR-590-3p knockdown facilitated skin flap survival by regulating PCNA, VCAM-1, and VEGFA levels. MiR-590-3p targeted VEGFA to regulate its expression. The knockdown of VEGFA significantly inhibited, while overexpression of VEGFA notably promoted the survival of skin flap.

Conclusion

ADSCs transplantation promotes skin flap survival by boosting angiogenesis. The miR-590-3p/VEGFA axis modulates skin flap angiogenesis and survival in ADSCs. These results reveal that interfering with miR-590-3p in ADSCs could potentially be a novel therapeutic target for the improvement of skin flap survival.

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ADSCs transplantation improve perforator flap survival.

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Agomir-590-3p transfected ADSCs inhibited perforator flap survival.

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MiR-590-3p targeted VEGFA 3′UTR to regulate its expression.

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The miR-590-3p/VEGFA axis in ADSCs modulates skin flap angiogenesis.

Advances in microRNA from adipose-derived mesenchymal stem cell-derived exosome: focusing on wound healing

Skin wounds are a common condition causing economic burden and they represent an urgent clinical need, especially chronic wounds. Numerous studies have been conducted on the applications of stem cell therapy in wound healing, with adipose-derived mesenchymal stem cells (ADMSCs) playing a major role since they can be isolated easily, yielding a high number of cells, the less invasive harvesting required, the longer life span and no ethical issues. However, the lack of standardized doses and protocols, the heterogeneity of clinical trials, as well as the incompatibility of the immune system limit its application. Recent studies have demonstrated that specific stem cell functions depend on paracrine factors, including extracellular vesicles, in which microRNAs in exosomes (Exo-miRNAs) are essential in controlling their functions. This paper describes the application and mechanism whereby ADMSC-Exo-miRNA regulates wound healing. ADMSC-Exo-miRNA is involved in various stages in wounds, including modulating the immune response and inflammation, accelerating skin cell proliferation and epithelialization, promoting vascular repair, and regulating collagen remodeling thereby reducing scar formation. In summary, this acellular therapy based on ADMSC-Exo-miRNA has considerable clinical potential, and provides reference values for developing new treatment strategies for wound healing.

Mesenchymal Stem Cells Attenuate Acute Lung Injury in Mice Partly by Suppressing Alveolar Macrophage Activation in a PGE2-Dependent Manner

Mesenchymal stem cells (MSCs) have been demonstrated to attenuate acute lung injury (ALI). We also found that they can suppress the activation of alveolar macrophages (AMs), which can partly account for their therapeutic effects. MSCs do not inherently own immunosuppressive effects, when co-cultured with inflammatory immune cells, MSCs can be activated by inflammatory cytokines and meanwhile exert immunosuppressive effects. In order to further research, RNA sequencing (RNA-seq) of MSCs cultured before and after co-culturing with activated macrophages was performed. The data suggested a total of 5268 differentially expressed genes (DEGs) along the process. We used the data of 2754 upregulated DEGs to develop a signaling network of genes and the transcription factors targeting them in order to predict the altered functions of MSCs after exposure to inflammatory stimuli. This constructed network revealed some critical target genes and potential roles of MSCs under inflammatory conditions. According to the network, Ptgs2 was assumed to be an important gene participating in the immunosuppressive effects of MSCs. We also identified significant increases in the expression of COX2 protein and the secretion of PGE2 from MSCs. The use of the COX2 inhibitor NS-398 restrained the secretion of PGE2 and reversed the suppression of macrophage activation by MSCs in vitro. In addition, a selective antagonist of PGE2 binding receptor (EP4 receptor), GW627368X, also reversed the inhibitory effects of MSCs on AMs and the protective effects in ALI mouse. In summary, the therapeutic effects of MSCs on ALI partly occur through suppressing AM activation via PGE2 binding to EP4 receptor.

Potency assays for human adipose-derived stem cells as a medicinal product toward wound healing

In pre-clinical studies, human adipose-derived stem cells (hASCs) have shown great promise as a treatment modality for healing of cutaneous wounds. The advantages of hASCs are that they are relatively easy to obtain in large numbers from basic liposuctions, they maintain their characteristics after long-term in vitro culture, and they possess low immunogenicity, which enables the use of hASCs from random donors. It has been hypothesized that hASCs exert their wound healing properties by reducing inflammation, inducing angiogenesis, and promoting fibroblast and keratinocyte growth. Due to the inherent variability associated with the donor-dependent nature of ASC-based products, it appears necessary that the quality of the different products is prospectively certified using a set of most relevant potency assays. In this review, we present an overview of the available methodologies to assess the Mode and the Mechanism of Action of hASCs, specifically in the wound healing scenario. In conclusion, we propose a panel of potential potency assays to include in the future production of ASC-based medicinal products.

Exosomes for diabetes syndrome: ongoing applications and perspective

Diabetes mellitus, ranking the ninth death cause in the world, is a kind of metabolic disease characterized by hyperglycemia. Without timely and effective treatment, many ensuing complications involved with heart,...

ADSCs enhance VEGFR3-mediated lymphangiogenesis via METTL3-mediated VEGF-C m6A modification to improve wound healing of diabetic foot ulcers

BACKGROUND

Adipose-derived mesenchymal stem cells (ADSCs) are an important focus in regenerative medicine. However, the biological function of ADSCs in the wound repair of diabetic foot ulcers (DFUs) remains unclear. This study aimed to determine the underlying mechanisms of ADSCs involved in the wound healing of DFUs.

METHODS

The cell surface markers cluster of differentiation 34 (CD34), stromal cell antigen 1 (Stro-1), cluster of differentiation 90 (CD90) and cluster of differentiation 105 (CD105) on ADSCs were identified by flow cytometry. Oil Red O staining and Alizarin Red S staining were performed to identify the multipotential differentiation of ADSCs into adipocytes and bone. The levels of Methyltransferase-like 3 (METTL3), vascular endothelial growth factor C (VEGF-C) and insulin-like growth factor 2 binding protein 2 (IGF2BP2) were assessed by RT-qPCR. CCK-8, Transwell and tubule formation assays were conducted to assess lymphatic endothelial cell (LEC) viability, migration and tubule formation ability, respectively. RIP and RNA pulldown assays were conducted to assess the interaction between IGF2BP2 and VEGF-C. The levels of VEGF-C, VEGFR3, LYVE-1 and IGF2BP2 proteins were assessed by Western blotting. The levels of VEGF-C in LECs were measured by ELISA.

RESULTS

Our findings illustrated that ADSCs accelerate LEC proliferation, migration and lymphangiogenesis via the METTL3 pathway and regulate VEGF-C expression via the METTL3/IGF2BP2-m6A pathway VEGF-C-mediated lymphangiogenesis via the METTL3/IGF2BP2-m6A pathway in DFU mice.

CONCLUSION

ADSCs enhance VEGFR3-mediated lymphangiogenesis via METTL3-mediated VEGF-C m6A modification to improve wound healing in DFUs, indicating that ADSCs may be regarded as a promising therapeutic strategy to promote wound healing in DFUs.

The long noncoding RNA PDK1-AS/miR-125b-5p/VEGFA axis modulates human dermal microvascular endothelial cell and human umbilical vein endothelial cell angiogenesis after thermal injury

Our previous study confirmed the critical role of miR-125b and vascular endothelial growth factor (VEGF) in burn wound repair., The present study was aimed to identify the role of long noncoding RNAs (lncRNAs) related to the function of miR-125b and VEGF in burn wound repair and the underlying mechanism. First, we found that lncRNA PDK1-AS and VEGFA expression was significantly increased in heat-denatured dermal tissue samples and in human dermal microvascular endothelial cells (HDMECs) and human umbilical vein endothelial cells (HUVECs) after thermal injury. PDK1-AS knockdown significantly inhibited cell viability, cumulative tube length, cell migratory ability, and cell invasion of thermally injured HDMECs and HUVECs. PDK1-AS knockdown decreased VEGFA protein levels in HDMECs and HUVECs. While overexpression of PDK1-AS showed the opposite effects. Online tools prediction and luciferase assay confirmed that miR-125b-5p targeted PDK1-AS and VEGFA 3'-untranslated region. miR-125b-5p inhibition significantly increased VEGFA protein levels and enhanced viability, cumulative tube length, migratory ability, and invasion of HUVECs and HDMECs. Furthermore, the effects of PDK1-AS knockdown on VEGFA protein levels in the two cell lines were partially reversed by miR-125b-5p inhibition. Finally, in the tissue samples, PDK1-AS and VEGFA expression was increased, while miR-125b-5p expression was decreased in heat-denatured dermal tissues; the expression of miR-125b-5p had a negative correlation with PDK1-AS and VEGFA, respectively, and PDK1-AS and VEGFA were positively correlated with each other in tissue samples. In conclusion, PDK1-AS relieves miR-125b-5p-induced inhibition on VEGFA by acting as a endogenous RNA, therefore modulating HDMEC and HUVEC angiogenesis after thermal injury.