Multilayered hydrogel scaffold construct with native tissue matched elastic modulus: A regenerative microenvironment for urethral scar-free healing.

The unsuitable deformation stimulus, harsh urine environment, and lack of a regenerative microenvironment (RME) prevent scaffold-based urethral repair and ultimately lead to irreversible urethral scarring. The researchers clarify the optimal elastic modulus of the urethral scaffolds for urethral repair and design a multilayered PVA hydrogel scaffold for urethral scar-free healing. The inner layer of the scaffold has self-healing properties, which ensures that the wound effectively resists harsh urine erosion, even when subjected to sutures. In addition, the scaffold's outer layer has an extracellular matrix-like structure that synergizes with adipose-derived stem cells to create a favorable RME. In vivo experiments confirm successful urethral scar-free healing using the PVA multilayered hydrogel scaffold. Further mechanistic study shows that the PVA multilayer hydrogel effectively resists the urine-induced inflammatory response and accelerates the transition of urethral wound healing to the proliferative phase by regulating macrophage polarization, thus providing favorable conditions for urethral scar-free healing. This study provides mechanical criteria for the fabrication of urethral tissue-engineered scaffolds, as well as important insights into their design.

Efficacy and Safety of Cell-Assisted Acellular Adipose Matrix Transfer for Volume Retention and Regeneration Compared to Hyaluronic Acid Filler Injection.

BACKGROUND: Cell-assisted acellular adipose matrix (AAM) transfer is a novel technique for soft tissue volume restoration, where AAM acts as a scaffold for tissue proliferation and promotes host cell migration, vascularization, and adipogenesis. This study aimed to evaluate the efficacy and safety of in vivo cell-assisted AAM transfer compared to hyaluronic acid (HA) filler injection. METHODS: Human adipose tissue was used to manufacture AAM, and murine adipose-derived stem cells (ASCs) were prepared. Nude mice were divided into four groups: AAM transfer (AT), ASC-assisted AAM transfer (CAT), HA filler injection (HI), and ASC-assisted HA filler injection (CHI). Eight weeks post-transfer, in vivo graft volume/weight, histology, and gene expression were analyzed to assess efficacy and safety. RESULTS: The AAM retained its three-dimensional scaffold structure without cellular components. AT/CAT showed lower volume retention than HA/CHA; however, CAT maintained a similar volume to HA. Histologically, adipogenesis and collagen formation were increased in AT/CAT compared to HA/CHA, with CAT showing the highest levels. CAT also demonstrated superior angiogenesis, adipogenesis, and gene expression (Vegf and Pparg), along with lower Il-6 expression, higher Il-10 expression, and reduced capsule formation, indicating better biocompatibility. CONCLUSIONS: Cell-assisted AAM transfer is a promising technique for volume retention and tissue regeneration, offering a safe and effective alternative to HA filler injections. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The Application of Photobiomodulation and Stem Cells Seeded on the Scaffold Accelerates the Wound Healing Process in Mice.

Introduction: The purpose of this research was to test the impact of seeding a hydrogel chitosan scaffold (HCS) with human adipose-derived stem cells (hADSCs) under the influence of photobiomodulation (PBM) on the remodeling step on the wound repairing process in mice. Methods: Thirty mice were randomly assigned to five groups (n=6 per group ): The control group (group 1) consisted of mice without any intervention. In group 2, an HCS was implanted into the wound. In group 3, a combination of HCS+hADSC was inserted into the wound. In group 4, an HCS was inserted into the wound and PBM was applied. In group 5, a combination of HCS+hADSCs was inserted into the wound, followed by PBM treatment. Results: Improvements in the injury closing rate (WCR) and microbial flora were observed in all groups. However, the highest WCRs were observed in group s 5, 4, 3, and 2 (all P values were 0.000). Groups 3-5 showed increased wound strength compared to group s 1 and 2, with group 2 demonstrating better results than group 1 (P values ranged from 0.000 to 0.013). Although group s 3-5 showed increases in certain stereological elements compared to group s 1 and 2, group 2 exhibited superior results in comparison with group 1 (P values ranged from 0.000 to 0.049). Conclusion: The joined use of HCS+hADSCs+PBM significantly accelerated the wound healing process during the maturation phase in healthy mice. This approach demonstrated superior wound healing compared to the use of HCS alone, hADSCs+HCS, or PBM+HCS. The findings suggest an additive effect when HCS+hADSCs+PBM are combined.

Collaborative Enhancement of Diabetic Wound Healing and Skin Regeneration by Recombinant Human Collagen Hydrogel and hADSCs.

Stem cell-based therapies hold significant promise for chronic wound healing and skin appendages regeneration, but challenges such as limited stem cell lifespan and poor biocompatibility of delivery systems hinder clinical application. In this study, an in situ delivery system for human adipose-derived stem cells is developed (hADSCs) to enhance diabetic wound healing. The system utilizes a photo-crosslinking recombinant human type III collagen (rHCIII) hydrogel to encapsulate hADSCs, termed the hADSCs@rHCIII hydrogel. This hydrogel undergoes local crosslinking at the wound site, establishing a sturdy 3D niche suitable for stem cell function. Consequently, the encapsulated hADSCs exhibit strong attachment and spreading within the hydrogels, maintaining their proliferation, metabolic activity, and viability for up to three weeks in vitro. Importantly, in vivo studies demonstrate that the hADSCs@rHCIII hydrogel achieves significant in situ delivery of stem cells, prolonging their retention within the wound. This ultimately enhances their immunomodulatory capabilities, promotes neovascularization and granulation tissue formation, facilitates matrix remodeling, and accelerates healing in a diabetic mouse wound model. Collectively, these findings highlight the potential of the conveniently-prepared and user-friendly hADSCs@rHCIII hydrogel as a promising therapeutic approach for diabetic wound treatment and in situ skin regeneration.

Immunocytochemistry assessment of vocal fold regeneration after cell-based implant in rabbits.

Objective: Cell-based outer vocal fold replacement (COVR) offers a potential treatment for severe vocal fold scarring or cancer reconstruction. Previous work in rabbits using human adipose-derived stem cells (ASC) in fibrin suggested that a hybrid structure emerged within 2 months, containing both implanted and host cells. This project uses immunocytochemistry to better define the phenotypic fate of implanted cells and features of the extracellular environment. Methods: Immunocytochemistry was performed on sections collected from rabbits 2 months after COVR implantation or scar surgery. Cellular targets included human leukocyte antigen (HLA), CD31, and smooth muscle actin (SMA). Results: HLA was present in all implanted sections and was used to identify human cells. In adjacent sections, HLA-positive cells were identified expressing CD31. SMA was not identified in the same cells as HLA. These markers were also present in injured vocal folds not receiving COVR. SMA protein content did not differ according to treatment. Conclusions: Implanted human ASC persist in rabbit vocal folds. Some appear to express CD31, an endothelial marker. Smooth muscle actin, a marker of myofibroblast phenotype, was present in all sections regardless of treatment, and was not identified in hASC. Host cells also infiltrate the structure, producing a hybrid host-graft vocal fold.

Clinical study of matrix vascular component gel combined with vacuum sealing drainage technique in chronic wounds.

OBJECTIVE: This study investigates the efficacy of the combination of extracellular matrix/stromal vascular fraction gel (ECM/SVF-gel) and vacuum sealing drainage (VSD) on chronic wounds. METHODS: From February 2021 to February 2022, 20 patients with chronic wounds were recruited and were divided into experimental and control groups, with 10 patients in each group. Following debridement, we applied various treatments to all cases for 2 weeks. Subsequently, we observed the changes in the wound area and calculated the rate of wound healing. Simultaneously, the wound margin tissues were collected for histological analysis, and the inflammatory cell infiltration within the wound was assessed using HE staining. Masson staining was used to observe the collagen deposition on the wound surface, and CD31 immunohistochemistry was used to count the number of microvessels to evaluate the angiogenesis (Clinical trial registration number: ChiCTR-INR-17013540). RESULTS: The therapeutic outcomes for all cases included in this study were favorable after a 2-week treatment period, and the wound area was smaller than before. The experimental group exhibited a significantly higher rate of wound healing compared to the control group. In the experimental group as revealed by HE staining, there was a marked reduction in the infiltration of inflammatory cells in the dermis. Masson staining demonstrated that the deposition of collagen fibers in the experimental group was more than the control group. CD31 immunohistochemistry showed an increased number of new blood vessels in the experimental group compared to the control group. Additionally, ECM/SVF-gel extract significantly enhanced the fibroblast proliferation and migration in vitro. CONCLUSION: The application of ECM/SVF gel combined with VSD in chronic wounds can accelerate wound healing by reducing inflammatory reaction, increasing collagen fiber deposition, and promoting angiogenesis. Therefore, the combination of ECM/SVF gel and VSD can be used as a simple, safe, and effective therapeutic method for chronic wounds.

Adipose-derived stem cells apoptosis rejuvenate radiation-impaired skin in mice via remodeling and rearranging dermal collagens matrix.

BACKGROUND: Chronic radiation dermatitis (CRD) is a late consequence of radiation with high incidence in patients receiving radiotherapy. Conventional therapies often yield unsatisfactory results. Therefore, this study aimed to explore the therapeutic potential and mechanism of adipose-derived stem cells (ADSCs) for CRD, paving the way for novel regenerative therapies in clinical practice. METHODS: Clinical CRD skin biopsies were analyzed to character the pathological changes of CRD skin and guided the animal modeling scheme. Subsequently, an in vivo analysisusing mouse CRD models was conducted to explore their effects of ADSCs on CRD, monitoring therapeutic impact for up to 8 weeks. Transcriptome sequencing and histologic sections analysis were performed to explore the potential therapeutic mechanism of ADSCs. Following observing extensive apoptosis of transplanted ADSCs, the therapeutic effect of ADSCs were compared with those of apoptosis-inhibited ADSCs. Multiphoton imaging and analysis of collagen morphologic features were employed to explain how translated ADSCs promote collagen remodeling at the microscopic level based on the contrast of morphology of collagen fibers. RESULTS: Following injection into CRD-afflicted skin, ADSCs therapy effectively mitigated symptoms of CRD, including acanthosis of the epidermis, fibrosis, and irregular collagen deposition, consistent with the possible therapeutic mechanism suggested by transcriptome sequencing. Notably, in vivo tracking revealed a significant reduction in ADSCs number due to extensive apoptosis. Inhibiting apoptosis in ADSCs partially tempered their therapeutic effects. Mechanically, analysis of collagen morphologic features indicated that translated ADSCs might promote dermal extracellular matrix remodeling through enlarging, lengthening, crimping, and evening collagen, counteracting the atrophy and rupture caused by irradiation. CONCLUSIONS: This study demonstrated that ADSCs underwent substantial apoptosis upon local skin transplantation, and paradoxically, this apoptosis is essential for their efficacy in promoting the regeneration of late radiation-impaired skin. Mechanically, transplanted ADSCs could promote the remodeling and rearrangement of radiation-damaged dermal collagen matrix.

A Novel Laboratory-Based Strategy for Single Adipocyte and Adipose-Derived Stem Cells Extraction for Transplantation: An Experimental Research.

BACKGROUND: Autologous fat grafting is widely used in plastic surgery. However, its main limitation is the low survival rate of fat grafts after transplantation. Transplantation of single adipocytes in combination with adipose-derived stem cells (ADSCs) could largely preserve the activity of the fat and improve graft survival. OBJECTIVE: To verify the long-term survival rate of single adipocyte graft in vivo and its viable fat morphology for future fat grafting. METHODS: Healthy adipose tissue was harvested and disassociated using fat dissociation solution, the Single-cell Suspension Preparation System (SSPS) was used to obtain a mixture of single adipocytes, ADSCs and stromal vascular fraction (SVF), and the structure of single adipocytes was verified by cell mask red and DAPI double staining. Nine male Balb/c nude mice were used, and three different graft volumes were established (0.05, 0.1 and 0.2 ml). For each mouse, four sites were selected for transplantation, one for macrofat and the other three for single adipocytes, and different transplant volumes 30, 60 and 90 days after transplantation. In each period, 3 mice were selected to measure the volume of fat graft. RESULTS: Double staining with cell mask red and DAPI confirmed that the nucleus was identified intracellularly, which also indicated that the adipocytes in the single-cell suspension were structurally complete. When evaluating the transplantation, the groups with a volume of 0.05 ml and 0.2 ml performed better in the single-cell fat group in all transplantation periods, the group with a volume of 0.1 ml performed better in the single-cell group in the 30- and 60-day transplantation, and the differences were significant (P<0.05). CONCLUSION: In this study, the SSPS was used to obtain a new transplant material containing single adipocytes and ADSCs by enzymatic hydrolysis of adipose tissue and converted into single cells. It effectively improved the survival rate of fat grafting and the long-term effect of transplantation. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Prevention of medication-related osteonecrosis of the jaw in mice by adipose-derived stem cells associated with activated autophagic flux.

Background/purpose: Medication-related osteonecrosis of the jaw (MRONJ) represents a rare yet serious adverse reaction associated with the prolonged use of anti-bone resorptive or anti-angiogenic agents. This study aimed to investigate the impact and underlying mechanisms of adipose-derived stem cells (ADSCs) in preventing MRONJ in a mouse model. Materials and methods: Following tooth extraction in MRONJ mice, ADSCs or PBS were administered via the tail vein. The healing progress of gingival epithelium and the extraction socket was assessed using a stereoscopic microscope and histological analysis. Immunofluorescence was employed to examine markers associated with autophagy (LC3 and SQSTM1) and apoptosis (Cleaved-CASP 3). Statistical analysis involved unpaired Student's t-test and ANOVA on ABI Prism 7500, with P-values below 0.05 deemed statistically significant. Results: ADSCs enhanced gingival epithelium migration and facilitated new bone formation. In the MRONJ group, the expressions of autophagy-related protein LC3 and SQSTM1 in gingival epithelium were concurrently elevated, which indicated autophagic flux was impaired. Conversely, when treated with ADSCs, the expression of LC3 and SQSTM1 were downregulated, similarly to the Control group. Mechanically, zoledronate induced a deficiency of autophagosome-lysosome fusion in epithelial cells, while ADSCs supernatant could promote the autolysosomes formation. Furthermore, ADSCs rescued the number of autophagy-related apoptotic cells in the gingival epithelium of MRONJ. Conclusion: ADSCs could effectively prevent the occurrence of MRONJ, likely through the activation of autophagic flux and the inhibition of autophagy-related apoptosis in gingival epithelium. These findings enhanced the understanding of MRONJ pathogenesis and propose a potential therapeutic target for this disease.

The Effect of Ionizing Irradiation on the Autotaxin-Lysophasphatidic Acid Axis and Interleukin-6/8 Secretion in Different Breast Cancer Cell Lines.

BACKGROUND: The Autotaxin (ATX)-lysophosphatidic acid (LPA) axis is involved in decreasing radiation sensitivity of breast tumor cells. This study aims to further elucidate the effect of irradiation on the ATX-LPA axis and cytokine secretion in different breast cancer cell lines to identify suitable breast cancer subtypes for targeted therapies. METHODS: Different breast cancer cell lines (MCF-7 (luminal A), BT-474 (luminal B), SKBR-3 (HER2-positive), MDA-MB-231 and MDA-MB-468 (triple-negative)) and the breast epithelial cell line MCF-10A were irradiated. The influence of irradiation on LPA receptor (LPAR) expression, ATX expression, and Interleukin (IL)-6 and IL-8 secretion was analyzed. Further, the effect of IL-6 and IL-8 on ATX expression of adipose-derived stem cells (ADSC) was investigated. RESULTS: Irradiation increased ATX and LPAR2 expression in MDA-MB-231 cells. Additionally, IL-6 secretion was enhanced in MDA-MB-231, and IL-8 secretion in MDA-MB-231 and MDA-MB-468. Stimulation of ADSC with IL-6 and IL-8 increased ATX expression in ADSC. CONCLUSIONS: Targeting ATX or its downstream signaling pathways might enhance the sensitivity of triple-negative breast cancer cells to radiation. Further exploration of the interplay between irradiation, the ATX-LPA axis, and inflammatory cytokines may elucidate novel pathways for overcoming radioresistance and improving individual treatment outcomes.

Subpial transplantation of adipose-derived stem cells alleviates paraplegia in a rat model of aortic occlusion/reperfusion-induced spinal cord infarction.

Background: Thoracoabdominal periprocedural occlusion/reperfusion injury of the spinal cord (SCII/R) can lead to devastating paraplegia, underscoring the critical need for effective interventions. However, our knowledge of optimal medical strategies and their efficacy remains limited. Preclinical investigations have shown promise in harnessing adult stem cells, including pluripotent and multipotent stem cells such as mesenchymal stem cells (MSCs), to address SCII/R by enhancing neuro-inflammation, axonal growth, and myelination. Particularly, growth factors derived from adipose tissue-derived MSCs (ADSCs) have been proposed to facilitate recovery. Despite advancements, achieving complete recovery remains a formidable challenge. Therefore, gaining a more profound insight into the role of ADSCs in alleviating SCII/R-induced paraplegia, including optimizing the delivery systems for therapies, is imperative. Materials and methods: In this study, we assessed the impact of subpial allogeneic rat adipose tissue-derived MSCs (rADSCs) transplantation on paraplegia using a rat SCII/R model induced by ephemeral aortic occlusion, known as the Taira-Marsala model. rADSCs were isolated from adipose tissue of male Sprague-Dawley rats, cultured, characterized, and cryopreserved. One week following the induction of paraplegia, rADSCs (n = 6) or physiological saline (n = 6) were transplanted. Hind limb motor function was evaluated before treatment and at 3-, 7-, and 14-days post-treatment using the Basso-Beattie-Bresnahan scoring system. Results: The rADSC-treated group demonstrated a significant improvement in hind limb motor function compared to the saline-treated group (p < 0.05), with 5 out of 6 rats exhibiting enhanced motor function following treatment. Conclusions: Our findings suggest that subpial rADSC engraftment may enhance SCII/R-induced paraplegia recovery. These initial results drive further research to validate this potential, understand the molecular mechanisms, and optimize therapies.

An ADSC-loaded dermal regeneration template promotes full-thickness wound healing.

Introduction: Full-thickness wounds lead to delayed wound healing and scarring. Adipose-derived stem cell (ADSC) grafting promotes wound healing and minimizes scarring, but the low efficiency of grafting has been a challenge. We hypothesized that loading ADSCs onto a clinically widely used dermal regeneration template (DRT) would improve the efficacy of ADSC grafting and promote full-thickness wound healing. Methods: ADSCs from human adipose tissue were isolated, expanded, and labeled with a cell tracker. Labeled ADSCs were loaded onto the DRT. The viability, the location of ADSCs on the DRT, and the abundance of ADSCs in the wound area were confirmed using CCK8 and fluorescence microscopy. Full-thickness wounds were created on Bama minipigs, which were applied with sham, ADSC, DRT, and ADSC-DRT. Wounds from the four groups were collected at the indicated time and histological analysis was performed. RNA-seq analysis was also conducted to identify transcriptional differences among the four groups. The identified genes by RNA-seq were verified by qPCR. Immunohistochemistry and western blotting were used to assess collagen deposition. In vitro, the supernatant of ADSCs was used to culture fibroblasts to investigate the effect of ADSCs on fibroblast transformation into myofibroblasts. Results: ADSCs were successfully isolated, marked, and loaded onto the DRT. The abundance of ADSCs in the wound area was significantly greater in the ADSC-DRT group than in the ADSC group. Moreover, the ADSC-DRT group exhibited better wound healing with improved re-epithelialization and denser collagen deposition than the other three groups. The RNA-seq results suggested that the application of the integrated ADSC-DRT system resulted in the differential expression of genes mainly associated with extracellular matrix remodeling. In vivo, wounds from the ADSC-DRT group exhibited an earlier increase in type III collagen deposition and alleviated scar formation. ADSCs inhibited the transformation of fibroblasts into myofibroblasts, along with increased levels of CTGF, FGF, and HGF in the supernatant of ADSCs. Wounds from the ADSC-DRT group had up-regulated expressions of CTGF, HGF, FGF, and MMP3. Conclusion: The integral of ADSC-DRT increased the efficacy of ADSC grafting, and promoted full-thickness wound healing with better extracellular matrix remodeling and alleviated scar formation.

A Comparative Analysis of the Advances in Stem Cell Therapy in Plastic Surgery: A Systematic Review of Current Applications and Future Directions.

Stem cell (SC) therapy is revolutionizing the field of plastic surgery by harnessing the regenerative abilities of SCs derived from adipose tissue and bone marrow to boost tissue repair and enhance aesthetic outcomes. This groundbreaking method enhances results in procedures such as fat grafting, facial rejuvenation, and wound healing. As studies advance, SC therapy shows potential for more sophisticated uses in both reconstructive and cosmetic surgery. The objective of this review is to comprehensively examine the advances in SC therapy within the field of plastic surgery, highlighting its current applications and exploring future directions. The systematic review was conducted on SC therapy in plastic surgery adhering to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and specific search criteria. This systematic review highlights these main outcomes, and SC therapy in plastic surgery enhances tissue repair and aesthetic outcomes by utilizing mesenchymal SCs such as adipose-derived SCs (ADSCs) and bone marrow-derived SCs (BMSCs), with platelet-rich plasma (PRP) providing additional support. Techniques such as scaffolds and cellular reprogramming are employed to guide SC growth, enabling tailored tissue engineering for complex regenerative procedures. This innovative approach accelerates healing, reduces scarring in reconstructive surgeries, improves skin texture, and ensures the natural integration of treated areas, ultimately yielding enhanced aesthetic results and transforming facial rejuvenation processes. SC therapy in plastic surgery holds great promise, but challenges such as protocol standardization, cost, and regulations still need to be addressed. SC therapy is leading innovative advancements in plastic surgery, offering superior outcomes and improved quality of life for patients. Interestingly, the future of plastic surgery is focused on integrating SC therapy for personalized and transformative treatments. Furthermore, interdisciplinary collaboration among bioengineers, clinicians, and regulatory bodies is essential for overcoming challenges and advancing SC research into clinical practice.

Research progress and application prospect of adipose-derived stem cell secretome in diabetes foot ulcers healing.

Diabetic foot ulcers (DFUs) are chronic wounds and one of the most common complications of diabetes, imposing significant physical and mental burdens on patients due to their poor prognosis and treatment efficacy. Adipose-derived stem cells (ADSCs) have been proven to promote wound healing, with studies increasingly attributing these beneficial effects to their paracrine actions. Consequently, research on ADSC secretome as a novel and promising alternative for DFU treatment has been extensively conducted. This article provides a comprehensive review of the mechanisms underlying refractory DFU wounds, the secretome of ADSCs, and its role in promoting wound healing in diabetes foot ulcers. And the review aims to provide reliable evidence for the clinical application of ADSC secretome in the treatment of refractory DFU wounds.

Comparison of Bioengineered Scaffolds for the Induction of Osteochondrogenic Differentiation of Human Adipose-Derived Stem Cells.

Osteochondral lesions may be due to trauma or congenital conditions. In both cases, therapy is limited because of the difficulty of tissue repair. Tissue engineering is a promising approach that relies on designed scaffolds with variable mechanical attributes to favor cell attachment and differentiation. Human adipose-derived stem cells (hASCs) are a very promising cell source in regenerative medicine with osteochondrogenic potential. Based on the assumption that stiffness influences cell commitment, we investigated three different scaffolds: a semisynthetic animal-derived GelMA hydrogel, a combined scaffold made of rigid PEGDA coated with a thin GelMA layer and a decellularized plant-based scaffold. We investigated the role of different biomechanical stimulations in the scaffold-induced osteochondral differentiation of hASCs. We demonstrated that all scaffolds support cell viability and spontaneous osteochondral differentiation without any exogenous factors. In particular, we observed mainly osteogenic commitment in higher stiffness microenvironments, as in the plant-based one, whereas in a dense and softer matrix, such as in GelMA hydrogel or GelMA-coated-PEGDA scaffold, chondrogenesis prevailed. We can induce a specific cell commitment by combining hASCs and scaffolds with particular mechanical attributes. However, in vivo studies are needed to fully elucidate the regenerative process and to eventually suggest it as a potential approach for regenerative medicine.

Exosomal miR­194 from adipose­derived stem cells impedes hypertrophic scar formation through targeting TGF­ß1.

Hypertrophic scars, which result from aberrant fibrosis and disorganized collagen synthesis by skin fibroblasts, emerge due to disrupted wound healing processes. These scars present significant psychosocial and functional challenges to affected individuals. The current treatment limitations largely arise from an incomplete understanding of the underlying mechanisms of hypertrophic scar development. Recent studies, however, have shed light on the potential of exosomal non­coding RNAs interventions to mitigate hypertrophic scar proliferation. The present study assessed the impact of exosomes derived from adipose­derived stem cells (ADSCs­Exos) on hypertrophic scar formation using a rabbit ear model. It employed hematoxylin and eosin staining, Masson's trichrome staining and immunohistochemical staining techniques to track scar progression. The comprehensive analysis of the present study encompassed the differential expression of non­coding RNAs, enrichment analyses of functional pathways, protein­protein interaction studies and micro (mi)RNA­mRNA interaction investigations. The results revealed a marked alteration in the expression levels of long non­coding RNAs and miRNAs following ADSCs­Exos treatment, with little changes observed in circular RNAs. Notably, miRNA (miR)­194 emerged as a critical regulator within the signaling pathways that govern hypertrophic scar formation. Dual­luciferase assays indicated a significant reduction in the promoter activity of TGF­ß1 following miR­194 overexpression. Reverse transcription­quantitative PCR and immunoblotting assays further validated the decrease in TGF­ß1 expression in the treated samples. In addition, the treatment resulted in diminished levels of inflammatory markers IL­1ß, TNF­α and IL­10. In vivo evidence strongly supported the role of miR­194 in attenuating hypertrophic scar formation through the suppression of TGF­ß1. The present study endorsed the strategic use of ADSCs­Exos, particularly through miR­194 modulation, as an effective strategy for reducing scar formation and lowering pro­inflammatory and fibrotic indicators such as TGF­ß1. Therefore, the present study advocated the targeted application of ADSCs­Exos, with an emphasis on miR­194 modulation, as a promising approach to managing proliferative scarring.

Comparison of the Therapeutic Efficacy and Autophagy-Mediated Mechanisms of Action of Urine-Derived and Adipose-Derived Stem Cells in Osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is a prevalent and disabling disease that affects a significant proportion of the global population. Urine-derived stem cells (USCs) have shown great prospects in the treatment of OA, but there is no study that has compared them with traditional stem cells. PURPOSE: This study aimed to compare the therapeutic efficacy and mechanisms of USCs and adipose-derived stem cells (ADSCs) for OA treatment. STUDY DESIGN: Controlled laboratory study. METHODS: We compared the biological properties of USCs and ADSCs using CCK-8, colony formation, EdU, adhesion, and apoptosis assays. We evaluated the protective effects of USCs and ADSCs on IL-1ß-treated OA chondrocytes by chemical staining, immunofluorescence, and Western blotting. We assessed the effects of USCs and ADSCs on chondrocyte autophagy by transmission electron microscopy, immunofluorescence, and Western blotting. We also compared the therapeutic efficacy of intra-articular injections of USCs and ADSCs by gross, histological, micro-computed tomography, and immunohistochemical analyses in an OA rat model induced by anterior cruciate ligament transection. RESULTS: USCs showed higher proliferation, colony formation, DNA synthesis, adhesion, and anti-apoptotic abilities than ADSCs. Both USCs and ADSCs increased the expression of cartilage-specific proteins and decreased the expression of matrix degradation-related proteins and inflammatory factors in OA chondrocytes. USCs had a greater advantage in suppressing MMP-13 and inflammatory factors than ADSCs. Both USCs and ADSCs enhanced autophagy in OA chondrocytes, with USCs being more effective than ADSCs. The autophagy inhibitor 3-MA reduced the enhanced autophagy and protective effects of USCs and ADSCs on OA chondrocytes. CONCLUSION: To our knowledge, this is the first study to explore the efficacy of USCs in the treatment of knee OA and to compare them with ADSCs. Considering the superior properties of USCs in terms of noninvasive acquisition, a high cost-benefit ratio, and low ethical concerns, our study suggests that they may be a more promising therapeutic option than ADSCs for OA treatment under rigorous regulatory pathways. CLINICAL RELEVANCE: USCs may be a superior cell source for stem cells to treat knee OA, and this study strengthens the evidence for the application of USCs.

Brown Adipose Stem Cell-Loaded Resilin Elastic Hydrogel Rebuilds Cardiac Function after Myocardial Infarction via Collagen I/III Reorganisation.

Irreversible fibrosis following myocardial infarction (MI) stiffens the infarcted myocardium, which remains challenging to restore. This study aimed to investigate whether the injectable RLP12 hydrogel, derived from recombinant resilin protein, could serve as a vehicle for stem cells to enhance the function of the infarcted myocardium. The RLP12 hydrogel was prepared and injected into the myocardium of rats with MI, and brown adipose-derived mesenchymal stem cells (BADSCs) were loaded. The survival and differentiation of BADSCs in vivo were investigated using immunofluorescence one week and four weeks after treatment, respectively. The heart function, MI area, collagen deposition, and microvessel density were further assessed four weeks after treatment through echocardiography, histology, immunohistochemistry, and immunofluorescence. The RLP12 hydrogel was prepared with a shear modulus of 10-15 kPa. Four weeks after transplantation, the RLP12 hydrogel significantly improved cardiac function by increasing microvessel density and reducing infarct area size and collagen deposition in MI rats. Furthermore, the distribution ratio of collagen III to I increased in both the centre and edge areas of the MI, indicating the improved compliance of the infarct heart. Moreover, the RLP12 hydrogel also promoted the survival and differentiation of BADSCs into cardiac troponin T- and α-smooth muscle-positive cells. The RLP12 hydrogel can be utilised as an injectable vehicle of BADSCs for treating MI and regulating collagen I and III expression profiles to improve the mechanical microenvironment of the infarct site, thereby restoring heart function. The study provides novel insights into the mechanical interactions between the hydrogel and the infarct microenvironment.

Single-cell RNA sequencing identifies inherent abnormalities of adipose-derived stem cells from nonlesional sites of patients with localized scleroderma.

BACKGROUND: Localized scleroderma (LoS) is an autoimmune disorder that primarily affects the skin, and is often treated with autologous fat grafting (AFG). Nevertheless, the retention rate of AFG in patients with LoS is typically low. We hypothesize that the low retention rate may be partially attributed to the inherent abnormalities of adipose-derived stem cells (ASCs) from nonlesional sites of patients with LoS. METHODS: We performed a comparative analysis of the single-cell transcriptome of the SVF from nonlesional sites of patients with LoS and healthy donors, including cellular compositional analysis, differential expression analysis, and high-dimensional weighted gene coexpression network analysis. Experimental validation with fluorescence-activated cell sorting and bleomycin-induced skin fibrosis mice models were conducted. RESULTS: We found a significant reduction in the relative proportion of CD55high interstitial progenitors in ASCs under the condition of LoS. Differential expression analysis revealed inherent abnormalities of ASCs from patients with LoS, including enhanced fibrogenesis, reduced anti-inflammatory properties, and increased oxidative stress. Compared with CD55low ASCs, CD55high ASCs expressed significantly higher levels of secreted protein genes that had functions related to anti-inflammation and tissue regeneration (such as CD55, MFAP5, and METRNL). Meanwhile, CD55high ASCs expressed significantly lower levels of secreted protein genes that promote inflammation, such as chemokine and complement protein genes. Furthermore, we provided in vivo experimental evidence that CD55high ASCs had superior treatment efficacy compared with CD55low ASCs in bleomycin-induced skin fibrosis mice models. CONCLUSIONS: We found that the low retention rate of AFG may be partially ascribed to the reduced pool of interstitial progenitor cells (CD55high) present within the ASC population in patients with LoS. We demonstrated the potential for improving the efficacy of AFG in the treatment of LoS by restoring the pool of interstitial progenitors within ASCs. Our study has significant implications for the field of translational regenerative medicine.

Osteogenic Protection against Fine Dust with Erucic Acid-Induced Exosomes.

Fine dust causes various disorders, including cardiovascular, neurological, renal, reproductive, motor, systemic, respiratory, and cancerous diseases. Therefore, it is essential to study functional materials to prevent these issues. This study investigated the beneficial effects of erucic acid against fine dust using methods such as miRNA profiling, quantitative PCR, flow cytometry, ELISA, and Alizarin O staining. Erucic acid effectively suppresses inflammation and upregulates osteogenic activators in fibroblasts exposed to fine dust. Additionally, erucic acid-induced exosomes (EIEs) strongly counteract the negative effects of fine dust on osteocytic differentiation and inflammation. Despite fine dust exposure, EIEs promoted osteocytic differentiation in adipose-derived stem cells (ASCs) and enhanced osteogenesis and phagocytosis in macrophages. The significant upregulation of RunX2 and BMP7 by EIEs indicates its strong role in osteocytic differentiation and protection against the effects of fine dust. EIEs also boosts immune activity and acts as an osteogenic trigger for macrophages. MicroRNA profiling revealed that EIEs dramatically upregulated miRNAs, including hsa-miRNA-1301-3p, hsa-miRNA-1908-5p, hsa-miRNA-423-5p, and hsa-miRNA-122-5p, which are associated with osteogenic differentiation and immunity. Therefore, EIEs show potential as biomaterials to prevent environment-borne diseases.