Search Results (259)

Osteoarthritis (OA) is the most common multifactorial joint disease characterized by progressive cartilage degradation and impaired tissue repair. Osteochondral defects represent a major clinical challenge within OA, as damage to cartilage and underlying bone can initiate degenerative changes and contribute to joint deterioration. The Wnt/β-catenin signaling pathway plays an important role in OA pathogenesis, and its dysregulation contributes to chondrocyte catabolism and cartilage loss. NOTUM, an extracellular Wnt inhibitor, has emerged as a potential therapeutic modulator capable of restoring signaling balance and promoting cartilage homeostasis. This study aimed to evaluate the efficacy of NOTUM compared with hyaluronic acid (HA), human adipose-derived mesenchymal stromal cells (hAd-MSCs), and Colchicine in a rabbit osteochondral defect model relevant to osteoarthritis. Twenty-seven New Zealand White rabbits underwent standardized femoral condyle injury and received single-dose treatments. Serum levels of cartilage biomarkers—Procollagen Type IIA N-terminal Propeptide (PIIANP) and Cartilage Oligomeric Matrix Protein (COMP)—were measured by ELISA at 4, 6, and 8 weeks post-surgery, and histological repair at week 12 was assessed using the modified O’Driscoll scoring system. NOTUM treatment significantly increased PIIANP and decreased COMP levels compared with HA, indicating enhanced cartilage synthesis and reduced degradation. Histological scores confirmed superior surface morphology and tissue composition in NOTUM-treated joints. These findings suggest that NOTUM performs a protective and regenerative effect through Wnt/β-catenin modulation, supporting the conclusion that it enhances osteochondral defect repair and motivating further studies of NOTUM as an OA therapy. Full article

Extracellular vesicles (EVs) derived from stem cells have emerged as promising mediators of osteogenesis, suggesting cell-free alternatives for bone tissue engineering and regenerative medicine. This review provides a comprehensive analysis of the main stem cell sources used for EV production, including bone marrow mesenchymal stem cells (BM-MSCs), adipose-derived stem cells (ADSCs), umbilical cord MSCs (UC-MSCs), induced pluripotent stem cells (iPSCs), and alternative stromal populations. Particular attention is given to the ways in which different conditioning and differentiation strategies, such as osteogenic induction, hypoxia, and mechanical stimulation, modulate EV cargo composition and enhance their therapeutic potential. We further discuss the in vitro models employed to evaluate EV-mediated bone regeneration, ranging from 2D cultures to complex 3D spheroids, scaffold-based systems, and bone organoids. Overall, this review emphasizes the current challenges related to standardization, scalable production, and clinical translation. It also outlines future directions, including bioengineering approaches, advanced preclinical models, and the integration of multi-omics approaches and artificial intelligence to optimize EV-based therapies. By integrating current knowledge, this work aims to guide researchers toward more consistent and physiologically relevant strategies to harness EVs for effective bone regeneration. Finally, this work uniquely integrates a comparative analysis of EVs from multiple stem cell sources with engineering strategies and emerging clinical perspectives, thereby providing an updated and translational framework for their application in bone regeneration. Full article

Dry Eye Disease (DED) is a multifactorial condition of the ocular surface, with one potential cause being damage from eye drops containing preservatives such as benzalkonium chloride (BAC). Current treatments for DED are unsatisfactory; therefore, it is worth exploring new therapies based on the secretome derived from stem cells. Human stem cells are important sources of growth factors and cytokines that promote tissue regeneration. The secretome of these cells can be obtained in vitro in conditioned medium (CM). The aim of the study was to evaluate the effect of CM derived from adipose-derived stem cells (hADSCs) and amniotic membrane-derived cells expressing mesenchymal and/or epithelial markers on limbal stem cells (LSCs) damaged by BAC, focusing on their regenerative potential. The study used two experimental models: the first focused on neutralizing the toxic effects of BAC when each CM was administered concurrently, and the second on the therapeutic effects of CM after prior cell damage by BAC. The effects of CM on LSCs were assessed, including apoptosis, cell cycle progression, proliferation, migration, and inflammation. CM from ADSCs and amniotic cells were shown to significantly reduce BAC-induced damage to LSCs. All tested CM promoted LSC regeneration, although their efficacy varied among treatments. The application of CM during BAC exposure yielded stronger and more consistent benefits than post-injury treatment. Full article

Osteoarthritis (OA) is the most common joint disorder globally, affecting approximately 595 million individuals and representing the first cause of chronic pain and disability. Recently, the infrapatellar fat pad (IFP), an intracapsular adipose tissue in the human knee joint, was recognized as an active and metabolically significant contributor to the pathophysiology of OA through the release of pro-inflammatory cytokines, adipokines, and growth factors that sustain inflammatory response, fibrotic remodeling, and neurogenic pain. The present review provides an overview of the pathophysiological significance of the IFP in OA and current and promising therapeutic strategies targeting this adipose structure. We summarize the available preclinical and translational evidence on conservative therapies, minimally invasive interventions, and surgical options as well as IFP-derived mesenchymal stromal cells as a potential cell source for cartilage repair. Overall, preclinical research indicates that the modulation of IFP inflammation and fibrosis could alleviate pain and delay the progression of the disease. The superficial location and its central role in the pathogenesis of OA make the IFP a promising therapeutic target in knee OA (KOA). Full article

Alginate-hydroxyapatite (AL) scaffolds modified with fibronectin (FN) or bioactive glass (BGMS10) have recently been characterized for their physicochemical properties and proposed as promising candidates for bone regeneration. Here, we present their first systematic biological evaluation, focusing on adhesion, proliferation, osteogenic differentiation, and in vivo host response. We compared FN-, BG-, and unmodified AL scaffolds using an immortalized mesenchymal stromal cell line (M-SOD) and primary human bone marrow-derived (BM-MSCs) and adipose-derived stromal cells (ASCs). FN scaffolds enhanced initial adhesion across all cell types and supported proliferation in M-SODs, but primary BM-MSCs and ASCs showed minimal expansion, regardless of scaffold type. BG scaffolds promoted expression of late-stage osteogenic markers in BM-MSCs, consistent with their ion release profile, but had limited impact on ASCs. In vivo subcutaneous implantation of acellular scaffolds in nude mice revealed robust host cell infiltration and extracellular matrix deposition across all scaffold types, confirming biocompatibility and integration. However, vascularization remained limited and did not differ substantially between formulations. Together, these findings highlight a critical discrepancy between immortalized and primary stromal cell responses to scaffold cues, underscoring the choice of cell source when evaluating the biocompatibility of a novel scaffold. At the same time, the effective in vivo integration observed across scaffold types emphasizes the importance of host tissue responses for translational evaluation of functional biomaterials. Full article

Adipose tissue plays a crucial role in the tumor microenvironment (TME), where its secreted extracellular vesicles (EVs) are involved in the complex signaling between tumor cells and surrounding stromal components. This study aims to unravel the mechanisms through which adipocyte-derived EVs influence breast cancer (BC) progression. Human mesenchymal stem cells (hMSCs) were differentiated into adipocytes following a 21-day induction protocol that led to significant accumulation of lipid droplets within the cells. EVs were isolated from the conditioned medium of both hMSC-derived adipocytes and BC cells. Particle size distribution, morphology, and uptake into the recipient cell were investigated via nanoparticle tracking analysis, transmission electron microscopy, and fluorescence microscopy, respectively. Our results show that BC-derived EVs notably impaired cell viability and modulated the expression of key genes involved in apoptosis resistance within stromal cells. On the other hand, stromal-derived EVs significantly altered tumor cell behavior, indicating a dynamic, bidirectional exchange of bioactive signals. These findings underscore the pivotal role of EV-mediated communication in the tumor-stroma interplay, suggesting that adipocyte-cancer cell EV crosstalk contributes to the remodeling of the TME, potentially facilitating tumor progression. Full article

Corneal regeneration has gained growing interest in recent years, largely due to the limitations of conventional treatments and the persistent shortage of donor tissue. Among the emerging strategies, extracellular vehicles (EVs), especially those derived from mesenchymal stromal cells (MSCs), have shown great promise as a cell-free therapeutic approach. These nanoscale vesicles contribute to corneal healing by modulating inflammation, supporting epithelial and stromal regeneration, and promoting nerve repair. Their therapeutic potential is largely attributed to the diverse and bioactive proteomic cargo they carry, including growth factors, cytokines, and proteins involved in extracellular matrix remodeling. This review presents a comprehensive examination of the proteomic landscape of EVs in the context of corneal regenerative medicine. We explore the biological functions of EVs in corneal epithelial repair, stromal remodeling, and neurodegeneration. In addition, we discuss advanced proteomic profiling techniques such as mass spectrometry (MS) and liquid chromatography–mass spectrometry (LC-MS/MS), which have been used to identify and characterize the protein contents of EVs. This review also compares the proteomic profiles of EVs derived from various MSC sources, including adipose tissue, bone marrow, and umbilical cord, and considers how environmental cues, such as hypoxia and inflammation, influence their protein composition. By consolidating current findings, this article aims to provide valuable insights for advancing the next generation of cell-free therapies for corneal repair and regeneration. Full article

Urethral stricture involves fibrotic narrowing of the urethral mucosa and spongiosum. Although urethroplasty using oral mucosal grafts is the gold standard for complex cases due to its high success rate, technical complexity limits its broader adoption. To address this, endoscopic transplantation of oral mucosal tissue has been proposed. While feasibility has been demonstrated, clinical efficacy remains suboptimal. Developing adjunctive factors that facilitate mucosal engraftment may improve outcomes of endoscopic transplantation. Extracellular vesicles (EVs)—membrane-bound nanoparticles secreted by cells that deliver miRNAs and other bioactive molecules—have recently emerged as promising candidates. We investigated EVs derived from four mesenchymal stromal cell (MSC) sources—stem cells from human exfoliated deciduous teeth (SHED), adipose tissue, umbilical cord, and bone marrow (BM)—isolated during both logarithmic (log) and stationary culture phases. miRNA profiling revealed distinct phase- and origin-specific signatures. SHED-derived EVs from the log phase and bone marrow-derived EVs from the stationary phase expressed miR-31, the let-7 family, and miR-205, suggesting early wound healing potential. In contrast, stationary-phase SHED-EVs and log-phase BM-MSC-EVs were enriched in the miR-99 family and miR-31, indicating potential roles in epithelial stabilization and fibrosis modulation. These findings support phase-specific application of MSC-EVs to optimize mucosal engraftment in transurethral reconstruction. Full article

Adipose-derived mesenchymal stromal/stem cells (AT-MSCs) can be typically isolated from adipose tissue using a minimally invasive procedure. However, since AT-MSCs are usually obtained from subcutaneous tissue, there is a risk of contamination with fibroblasts (FBs), which can reduce the differentiation potential of AT-MSCs. To avoid this contamination, it is crucial to identify specific markers to effectively distinguish AT-MSCs from FBs. Analysis of microarray data obtained from three studies (GSE9451, GSE66084, GSE94667, and GSE38947) revealed 123 genes expressed at levels more than 1.5-fold higher in AT-MSCs compared to FBs. Using STRING, a protein-protein interaction (PPI) network consisting of 80 nodes and 197 edges was identified within the 123 genes. Further investigation using Molecular Complex Detection in Cytoscape identified a module of 12 genes: COL3A1, FBN1, COL4A1, COL5A2, POSTN, CTGF, SPARC, HSPG2, FSTL1, LAMA2, LAMC1, COL16A1. Gene Ontology analysis revealed that these genes were enriched in extracellular region (GO: 0005576). Additionally, these 12 genes corresponded to the top 12 of the 15 hub genes calculated using the Maximal Clique Centrality algorithm. The results of this study suggest that these 12 genes may serve as markers for distinguishing AT-MSCs from FBs, offering potential applications in regenerative medicine. Full article

Autologous fat grafting of human lipoaspirate (LA) is increasingly used in reconstructive and cosmetic surgery for lipofilling and stem cell-rich “nanofat” reinjection for regenerative medicine. While commercial devices (e.g., REVOLVE and Puregraft) are available, many surgeons use non-standardized manual washing techniques, leading to inconsistent graft retention (20–80%). Moreover, no system can unite washing directly with mechanical processing to produce a nanofat-like product directly from raw LA. We developed a novel preparation device (PD) that is designed for peristaltic pump-driven washing of LA and can be seamlessly combined with our previously developed Emulsification and Micronization Device (EMD) into an automated closed-loop platform. Human LA samples were washed with the PD and compared to standard manual washing via visual colorimetric analysis. We then evaluated the mechanical processing of PD-washed LA using our EMD and assessed cell count, viability, and stromal vascular fraction-derived subpopulations (i.e., mesenchymal stem cells, endothelial progenitor cells (EPCs), pericytes, transit-amplifying (TA) progenitor cells, and supra-adventitial adipose stromal cells). Recirculating LA through the PD for at least one minute resulted in sufficient mixing, producing LA with equivalent color and quality to manual washing. Integrating the EMD within a platform enabled both washing and mechanical processing under peristaltic flow, enriching key subpopulations compared to manual methods. Thus, our fluidic platform effectively washes LA in a closed-loop system, minimizing LA tissue manipulation and opportunity for contamination while also simplifying the workflow for mechanical processing. Further refinement and automation of this platform would enhance the reproducibility and quality of small-volume fat grafts, cell-assisted lipotransfer, and stem/progenitor cell injections to promote wound healing and angiogenesis. Full article

Photobiomodulation (PBM) utilizes different wavelengths of light to modulate cellular functions and has emerged as a promising approach in regenerative medicine. In this study, we examined the effects of blue (455 nm), red (660 nm), and near-infrared (810 nm) light, both individually and in combination, on human adipose-derived mesenchymal stem/stromal cells (adMSCs). A single, short-term exposure of adMSCs in suspension to these wavelengths using an integrating sphere revealed distinct wavelength- and dose-dependent cellular responses. Blue light exposure led to a dose-dependent increase in intracellular reactive oxygen species, accompanied by reduced cell proliferation, metabolic activity, interleukin-6/interleukin-8 secretion, and adipogenic differentiation. In contrast, red and near-infrared light preserved cell viability and metabolic function while enhancing cell migration, consistent with their documented ability to stimulate proliferation and mitochondrial activity in mesenchymal stem cells. These findings highlight the necessity of precise wavelength and dosage selection in PBM applications and support the potential of PBM as a customizable tool for optimizing patient-specific regenerative therapies. Full article

Nanotechnology is transforming contemporary medicine by providing cutting-edge tools for the treatment and diagnosis of complex disorders. Advanced techniques such as bioimaging and photodynamic therapy (PDT) combine early diagnosis and targeted therapy, offering a more precise approach than conventional treatments. However, a significant obstacle for PDT is the need to selectively deliver photosensitizers to disease sites while minimizing systemic side effects. In this context, mesenchymal stem cells have emerged as promising biological carriers due to their natural tropism towards tumors, low immunogenicity, and their ability to overcome biological barriers. In this study, two push–pull compounds, NPI-PTZ and BTZ-PTZ, phenothiazine derivatives featuring aggregation-induced emission (AIE) abilities, were analyzed. These molecules proved to be excellent fluorescent probes and photosensitizing agents. When administered to human bone marrow-derived multipotent stromal cells (hBM-MSCs) and human adipose multipotent stem cells (hASCs), the compounds were efficiently internalized, maintained a stable fluorescent emission for several days, and showed phototoxicity after irradiation, without inducing major cytotoxic effects under normal conditions. These results highlight the potential of NPI-PTZ and BTZ-PTZ combined with mesenchymal stem cells as theranostic tools, bridging bioimaging and PDT, and suggest new possibilities for advanced therapeutic approaches in clinical applications. Full article

Mesenchymal stromal cells (MSCs), such as bone marrow-derived cells (BMSCs) and adipose-derived cells (ASCs), are key candidates for bone regeneration therapies but have not yet been integrated into standard clinical practice due to heterogeneity in their osteogenic capacities. This study investigated the osteogenic differentiation of porcine BMSCs and ASCs by analyzing BMP-2-induced receptor expression and the effects of inhibiting BMP, TGF-β, and FGF signaling pathways. While pBMSCs underwent osteogenesis in standard differentiation medium, pASCs required BMP-2 stimulation to initiate this process. BMP signaling inhibition via dorsomorphin suppressed osteogenic differentiation, but this effect was reversed by co-inhibition of TGF-β or FGF signaling. Notably, simultaneous inhibition of TGF-β and FGF in the presence of BMP-2 optimized osteogenic differentiation in both pMSC types. In pASCs, successful differentiation correlated with early activation of p38 MAPK and Wnt signaling pathways, with BMP-2 serving as a primary driver, while TGF-β and FGF pathways acted as modulators. These findings highlight the importance of signaling context and MSC tissue origin in bone formation and suggest that tailored modulation of BMP, TGF-β, and FGF signaling will be necessary in future in vivo applications to maximize the regenerative potential of MSC-based therapies. Full article

Background: Mesenchymal stem cell-based therapy may be indicated in ischaemic heart disease. The use of autologous adipose-derived mesenchymal stromal cells (AdMSCs) offers regenerative potential due to their paracrine effects. The aim of this study was to expand and characterise adult human thymus-derived MSCs harvested during open heart surgery with respect to their stem cell and paracrine properties. Methods: Enzymatically and non-enzymatically isolated human thymic AdMSCs (ThyAdMSCs) were cultured in xeno-free media containing pooled human platelet lysate (pPL). MSC characterisation was performed. Ex vivo expanded ThyAdMSCs were differentiated into three lineages. Proliferative capacity and immunomodulatory properties were assessed by proliferation assays and mixed lymphocyte reaction, respectively. Gene expression analysis was performed by qPCR. Results: Both isolation methods yielded fibroblast-like cells with plastic adherence and high proliferation. Flow cytometry revealed distinct expression of MSC markers in the absence of haematopoietic cell surface markers. Ex vivo expanded ThyAdMSCs could be differentiated into adipocytes, osteocytes, and chondrocytes. Activated peripheral blood mononuclear cells were significantly reduced when co-cultured with ThyAdMSCs, indicating their ability to inhibit immune cells in vitro. Gene expression analysis showed significantly less IFNγ and TNFα, indicating an alteration of the activated and pro-inflammatory state in the presence of ThyAdMSCs. Conclusions: These results demonstrate an efficient method to generate AdMSCs from human thymus. These MSCs have a strong immunomodulatory capacity and are, therefore, a promising cell source for regenerative medicine. The culture conditions are crucial for cells to proliferate in culture. Further research could explore the use of ThyAdMSCs or their secretome in surgical procedures. Full article

Cell therapy utilizing mesenchymal stromal cells (MSCs) through paracrine mechanisms holds promise for regenerative purposes. Peritoneal fibrosis (PF) is a significant complication of peritoneal dialysis. Various strategies have been proposed to protect the peritoneal membrane (PM). This study explores the effectiveness of adipose-tissue-derived stem cells (ASCs) and extracellular vesicles (EVs) at mitigating PF using a rat model of PF induced by chlorhexidine gluconate. ASC and EV treatments effectively prevented an increase in the thickness of the PM and diminished the number of myofibroblasts, fibronectin expression, collagen III expression, and PF-related factors such as TGF-β and FSP-1. Smad3 gene expression decreased in the treatment groups, whereas Smad7 gene expression increased in treated animals. In addition, ASC and EV injections showed potent anti-inflammatory effects. Glucose transport through the PM remained unaffected in relation to the PF group; both treatments promoted an increase in ultrafiltration (UF) capacity. The PF+EVs treated group showed the highest increase in UF capacity. Another critical aspect of ASC and EV treatments was their impact on neoangiogenesis in the PM which is vital for UF capacity. Although the treated groups displayed a significant decrease in VEGF expression in the PM, peritoneal function remained effective. In conclusion, within the experimental PF model, both ASC and EV treatments demonstrated anti-inflammatory effects and comparably hindered the progression of PF. The EV treatment exhibited superior preservation of peritoneal function, along with enhanced UF capacity. These findings suggest the potential of ASCs and EVs as novel therapeutic approaches to prevent the development of PF associated with peritoneal dialysis. Full article