Skin contracts during wound healing to facilitate wound closure. In some patients, skin contraction can lead to the formation of skin contractures that limit movement, impair function, and significantly impact well-being. Current treatment options for skin contractures are burdensome for patients, and there is a high risk of recurrence. Autologous fat grafting can improve the structure and function of scarred skin; however, relatively little is known about the effect of fat on skin contraction. In this study, an in vitro tissue-engineered model of human skin was used to test the effects of adipose tissue and adipose-derived stromal cells on skin contraction. Untreated tissue-engineered skin contracted to approximately 60% of the original area over 14 days in culture. The addition of adipose tissue reduced this contraction by 50%. Adipose tissue, which was emulsified or concentrated and high doses of adipose-derived stromal cells (ADSC) were able to inhibit contraction to a similar degree; however, lower doses of ADSC did not show the same effect. In conclusion, the subcutaneous application of adipose tissue has the potential to inhibit skin contraction. This study provides in vitro evidence to support the use of autologous fat grafting to prevent skin contraction in patients most at risk.

Systemic sclerosis (SSc) is a connective tissue disease characterized by progressive fibrosis of the skin and visceral organs, to date, skin fibrosis remains a clinical therapeutic challenge. Adipose-derived mesenchymal stem cells (AMSCs) have been considered extremely promising for the treatment of SSc, and the biological effects of MSCs are partly attributed to the secretion of exosomes (exos). Our aim was to determine whether exosomes derived from AMSCs have parental biological effects to AMSCs in the therapy of SSc skin fibrosis. In vitro cellular experiments, AMSCs and SSc skin fibroblasts were cocultured in direct contact and transwell indirect contact at a ratio of 1:5 and 1:10, respectively, then exosomes were extracted from the cell culture supernatant of AMSCs and identified, and the exosomes were cocultured with fibroblasts to investigate the effects of AMSCs and exosomes on fibroblast collagen synthesis. Repeated subcutaneous injections of bleomycin (BLM) to construct a model of SSc skin fibrosis in vivo experiments, then AMSCs and exosomes were injected subcutaneously to investigate their effects on skin fibrosis in the BLM mice. The results revealed that exosomes had similar biological functions to AMSCs, by inhibiting the TGF-β1/Smad3 axis, which alleviated collagen synthesis in skin fibroblasts from SSc patients and skin fibrosis in BLM models. In conclusion, AMSCs-derived exosomes may be "rising star candidates" for the treatment of SSc skin fibrosis.

Due to the contradictory and temporally variable effects of transforming growth factor-β (TGF-β) and the Wnt/β-catenin pathways on osteogenic differentiation in different stem cell types, we sought to examine the activity of these pathways as well as their interaction during the osteogenic differentiation of the osteo-induced adiposederived mesenchymal stem cells (AD-MSCs).

The osteo-induced AD-MSCs were treated with TGF-β1 (1 ng/mL) either alone or together with its antagonist SB- 431542 (10 μM) or that of the Wnt antagonist, inhibitor of Wnt production 2 (IWP2) (3 μM), every 3 days for 21 days. Cells were then analyzed for calcium deposit, bone matrix production, and the osteogenic markers gene expression.

Our results showed firstly that, either of the pathways is active since the mRNA expressions of their respective target genes, PAI-1 and Cyclin D1 were detectable although the latter was at a very low level. Secondly that, treatment with TGF-β1 decreased levels of calcium deposit, bone matrix production and the osteogenic markers gene expression. Accordingly, osteogenesis was induced in those treated with SB either alone or together with the TGF-β1, pointing to inhibitory effect of TGF-β pathway on osteogenic differentiation. Thirdly that following treatment with IWP2 and TGF-β1, the inhibitory effect of TGF-β1 on bone matrix production was reversed. Fourthly, there was constantly low expression of Wnt3amRNA but progressively increasing that of its endogenous antagonist Dkk-1mRNA throughout.

Together these results suggest that TGF-β1 requires the active Wnt/β-catenin signaling pathway to exert its inhibitory effects on osteogenic differentiation of AD-MSCs.

Cartilage injuries are extremely common in the general population, and conventional interventions have failed to produce optimal results. Tissue engineering (TE) technology has been developed to produce neocartilage for use in a variety of cartilage-related conditions. However, progress in the field of cartilage TE has historically been difficult due to the high functional demand and avascular nature of the tissue. Recent advancements in cell sourcing, biostimulation, and scaffold technology have revolutionized the field and made the clinical application of this technology a reality. Cartilage engineering technology will continue to expand its horizons to fully integrate three-dimensional printing, gene editing, and optimal cell sourcing in the future. This review focuses on the recent advancements in the field of cartilage TE and the landscape of clinical treatments for a variety of cartilage-related conditions.

The selection of appropriate cell sources is vital for the regeneration and repair of tendons using stem cell-based approaches. Human adipose-derived stem cells (hADSCs) have emerged as a promising therapeutic strategy for tendon injuries. However, the heterogeneity of hADSCs can lead to inconsistent or suboptimal therapeutic outcomes. In this study, we isolated and identified a tenomodulin (TNMD)-positive subpopulation from hADSCs (TNMD+hADSCs) using flow cytometry and then assessed the cellular response of this subpopulation to decellularized tendon slices (DTSs), including cell proliferation, migration, and tenogenic differentiation, using the CCK-8 assay, transwell migration assay, and quantitative real-time polymerase chain reaction. Our findings revealed that TNMD+hADSCs maintained the general characteristics of stem cells and exhibited significantly higher expressions of tendon-related markers compared to hADSCs. Importantly, DTSs significantly enhanced the proliferation, migration, and tenogenic differentiation of TNMD+hADSCs. This study provides preliminary experimental evidence for the translational application of ADSCs for tendon regeneration and repair.

Mesenchymal stromal cells (MSCs) and Dexamethasone (Dex) are both effective methods to treat inflammatory diseases. However, the interaction between inflammatory factors, Dex, and MSCs in repair is not fully understood. The purpose of this study is to clarify the effects and mechanisms of glucocorticoids on the tissue repair characteristics of MSCs in an inflammatory environment.

This is an experimental study. Human adipose-derived mesenchymal stromal cells (hASCs) were cultured, and Long non-coding RNA (lncRNA) differentiation antagonizing nonprotein coding RNA (DANCR) expression was detected after treatment with Dex and inflammation factors. Additionally, DANCR was knockdown or overexpressed before Dex or tumor necrosis factor-alpha (TNF-α) treatments, respectively. hASC proliferation, cell cycle, and migration ability were analyzed to evaluate the effects of DANCR in hASCs treated with Dex or TNF-α. Nuclear factor-kB (NF-κB) pathway inhibitors were used to clarify the signal pathway that DANCR involved. All data are presented as the mean ± standard deviation. The two-tailed Student's t-test or one-way analysis of variance (ANOVA) was used to determine the statistical differences between groups.

Dex decreased the proliferation and migration of hASCs and upregulated DANCR expression in a dosage-dependent relationship. The knockdown of DANCR reversed Dex's repression of hASC proliferation. Moreover, DANCR was decreased by inflammatory cytokines, and overexpressing DANCR alleviated the promotion effects of TNF-α on hASC proliferation and migration. Furthermore, mechanistic investigation validated that DANCR was involved in the NF- κB signaling pathway.

We identified a lncRNA, DANCR, that was involved in Dex and inflammation-affected hASC proliferation and migration. Dex reduced the proliferation and migration of hASCs through DANCR while exerting its anti-inflammatory effects. Thus, it is suggested to avoid the simultaneous application of hASCs and steroids in clinical practice. These results enrich our understanding of the versatile function of lncRNAs in the crosstalk of inflammation conditions and MSCs.

The limited availability of corneal tissue grafts poses significant challenges in the treatment of corneal blindness. Novel treatment utilizes stem cell grafts transplanted from the healthy side of the cornea to the damaged side. However, this procedure is only possible for those who have one-sided corneal blindness. Human stem cells offer promising potential for corneal tissue engineering, providing an alternative solution. Among the different types of stem cells, mesenchymal stem cells (MSCs) stand out due to their abundance and ease of isolation. Human MSCs can be derived from bone marrow, adipose, and umbilical cord tissues. Differentiating MSC toward corneal tissue can be achieved through several methods including chemical induction and co-culture with adult corneal cells such as human limbal epithelial stem cells (LESCs) and human corneal epithelial cells (hTCEpi). Adipose-derived stem cells (ADSCs) are the most common type of MSC that has been studied for corneal differentiation. Corneal epithelial cells are the most common corneal cell type targeted by researchers for corneal differentiation. Chemical induction with small molecules, especially bone morphogenetic protein 4 (BMP4), all-trans retinoic acid (ATRA), and epidermal growth factor (EGF), has gained more popularity in corneal epithelial cell differentiation. This review highlights the current progress in utilizing MSCs for corneal differentiation studies, showcasing their potential to revolutionize treatments for corneal blindness.

PURPOSE OF REVIEW: The purpose of this narrative review is to evaluate the efficacy of the most commonly studied intradiscal biologics used for the treatment and alleviation of chronic intractable discogenic low back pain. Additionally, it explores the therapeutic potential and durability of these novel treatment options. RECENT FINDINGS: Recently published literature highlights the therapeutic potential of intradiscal biologics, such as mesenchymal stem cells, platelet-rich plasma, and alpha-2-macroglobulin, in promoting chondrogenesis within the lumbar intervertebral discs to treat discogenic low back pain. Studies demonstrate significant improvements in pain relief, physical function, and quality of life post-treatment. A comprehensive review of the literature evaluating the efficacy of intradiscal biologics suggests some evidence supporting its efficacy in treating discogenic low back pain. However, more rigorous studies into mechanistic modulation and large-scale randomized trials as well as a more thorough understanding of adverse events will be instrumental for including these therapies into clinical practice paradigms.

Ageing populations globally are associated with increased musculoskeletal disease, including osteoporosis and sarcopenia. These conditions place a significant burden of disease on the individual, society and the economy. To address this, we need to understand the underpinning biological changes, including stem cell exhaustion, which plays a key role in the ageing of the musculoskeletal system. This review of the recent evidence provides an overview of the associated biological processes. The review utilised the PubMed/Medline, Science Direct, and Google Scholar databases. Mechanisms of ageing identified involve a reaction to the chronic inflammation and oxidative stress associated with ageing, resulting in progenitor cell senescence and adipogenic differentiation, leading to decreased mass and quality of both bone and muscle tissue. Although the mechanisms underpinning stem cell exhaustion are unclear, it remains a promising avenue through which to identify new strategies for prevention, detection and management.

Finding novel treatments for cardiovascular diseases (CVDs) is a hot topic in medicine; cell-based therapies have reported promising news for controlling dangerous complications of heart disease such as myocardial infarction (MI) and heart failure (HF). Various progenitor/stem cells were tested in various in-vivo, in-vitro, and clinical studies for regeneration or repairing the injured tissue in the myocardial to accelerate the healing. Fetal, adult, embryonic, and induced pluripotent stem cells (iPSC) have revealed the proper potency for cardiac tissue repair. As an essential communicator among cells, exosomes with specific contacts (proteins, lncRNAs, and miRNAs) greatly promote cardiac rehabilitation. Interestingly, stem cell-derived exosomes have more efficiency than stem cell transplantation. Therefore, stem cells induced pluripotent stem cells (iPSCs), embryonic stem cells (ESCs), cardiac stem cells (CDC), and skeletal myoblasts) and their-derived exosomes will probably be considered an alternative therapy for CVDs remedy. In addition, stem cell-derived exosomes have been used in the diagnosis/prognosis of heart diseases. In this review, we explained the advances of stem cells/exosome-based treatment, their beneficial effects, and underlying mechanisms, which will present new insights in the clinical field in the future.

Increasing attention has been paid to the development of effective strategies for articular cartilage (AC) and osteochondral (OC) regeneration due to their limited self-reparative capacities and the shortage of timely and appropriate clinical treatments. Traditional cell-dependent tissue engineering faces various challenges such as restricted cell sources, phenotypic alterations, and immune rejection. In contrast, endogenous tissue engineering represents a promising alternative, leveraging acellular biomaterials to guide endogenous cells to the injury site and stimulate their intrinsic regenerative potential. This review provides a comprehensive overview of recent advancements in endogenous tissue engineering strategies for AC and OC regeneration, with a focus on the tissue engineering triad comprising endogenous stem/progenitor cells (ESPCs), scaffolds, and biomolecules. Multiple types of ESPCs present within the AC and OC microenvironment, including bone marrow-derived mesenchymal stem cells (BMSCs), adipose-derived mesenchymal stem cells (AD-MSCs), synovial membrane-derived mesenchymal stem cells (SM-MSCs), and AC-derived stem/progenitor cells (CSPCs), exhibit the ability to migrate toward injury sites and demonstrate pro-regenerative properties. The fabrication and characteristics of scaffolds in various formats including hydrogels, porous sponges, electrospun fibers, particles, films, multilayer scaffolds, bioceramics, and bioglass, highlighting their suitability for AC and OC repair, are systemically summarized. Furthermore, the review emphasizes the pivotal role of biomolecules in facilitating ESPCs migration, adhesion, chondrogenesis, osteogenesis, as well as regulating inflammation, aging, and hypertrophy-critical processes for endogenous AC and OC regeneration. Insights into the applications of endogenous tissue engineering strategies for in vivo AC and OC regeneration are provided along with a discussion on future perspectives to enhance regenerative outcomes.

Bone marrow aspirate concentrate (BMAC) and adipose-derived stromal vascular fraction (ADSVF) are the most marketed stem cell therapies to treat a variety of conditions in the general population and elite athletes. Both tissues have been used interchangeably clinically even though their detailed composition, heterogeneity, and mechanisms of action have neither been rigorously inventoried nor compared. This lack of information has prevented investigations into ideal dosages and has facilitated anecdata and misinformation. Here, we analyzed single-cell transcriptomes, proteomes, and flow cytometry profiles from paired clinical-grade BMAC and ADSVF. This comparative transcriptional atlas challenges the prevalent notion that there is one therapeutic cell type present in both tissues. We also provide data of surface markers that may enable isolation and investigation of cell (sub)populations. Furthermore, the proteome atlas highlights intertissue and interpatient heterogeneity of injected proteins with potentially regenerative or immunomodulatory capacities. An interactive webtool is available online.

To investigate the level of cellular senescence in stem cells derived from microfragmented abdominal adipose tissue harvested from patients with knee osteoarthritis (OA).

Stem cells harvested from microfragmented abdominal adipose tissue from 20 patients with knee OA, aged 29-65 years (mean = 49.8, SD = 9.58), were analysed as a function of patient age and compared with control cells exhibiting signs of cellular senescence. Steady-state mRNA levels of a panel of genes associated with senescence were measured by qPCR. Intracellular senescence-associated proteins p16 and p21, and senescence-associated β-galactosidase activity were measured by flow cytometry. Cellular proliferation was assessed using a 5-ethynyl-2'-deoxyuridine proliferation assay. Stemness was assessed by stem cell surface markers using flow cytometry and the capacity to undergo adipogenic and osteogenic differentiation in vitro.

No correlation was found between cellular senescence levels of the microfragmented adipose tissue-derived stem cells and patient age for any of the standard assays used to quantify senescence. The level of cellular senescence was generally low across all senescence-associated assays compared to the positive senescence control. Stemness was verified for all samples. An increased capacity to undergo adipogenic differentiation was shown with increasing patient age (p = 0.02). No effect of patient age was found for osteogenic differentiation.

Autologous microfragmented adipose tissue-derived stem cells may be used in clinical trials of knee OA of patients aged 29-65 years, at least until passage 4, as they show stemness potential and negligible senescence in vitro.

Not applicable.

Mesenchymal stem cells (MSCs) are increasingly recognized for their regenerative potential. However, their clinical application is hindered by their inherent variability, which is influenced by various factors, such as the tissue source, culture conditions, and passage number.

MSCs were sourced from clinically relevant tissues, including adipose tissue-derived MSCs (ADMSCs, n = 2), chorionic villi-derived MSCs (CMMSCs, n = 2), amniotic membrane-derived MSCs (AMMSCs, n = 3), and umbilical cord-derived MSCs (UCMSCs, n = 3). Passages included the umbilical cord at P0 (UCMSCP0, n = 2), P3 (UCMSCP3, n = 2), and P5 (UCMSCP5, n = 2) as well as the umbilical cord at P5 cultured under low-oxygen conditions (UCMSCP5L, n = 2).

We observed that MSCs from different tissue origins clustered into six distinct functional subpopulations, each with varying proportions. Notably, ADMSCs exhibited a higher proportion of subpopulations associated with vascular regeneration, suggesting that they are beneficial for applications in vascular regeneration. Additionally, CMMSCs had a high proportion of subpopulations associated with reproductive processes. UCMSCP5 and UCMSCP5L had higher proportions of subpopulations related to female reproductive function than those for earlier passages. Furthermore, UCMSCP5L, cultured under low-oxygen (hypoxic) conditions, had a high proportion of subpopulations associated with pro-angiogenic characteristics, with implications for optimizing vascular regeneration.

This study revealed variation in the distribution of MSC subpopulations among different tissue sources, passages, and culture conditions, including differences in functions related to vascular and reproductive system regeneration. These findings hold promise for personalized regenerative medicine and may lead to more effective clinical treatments across a spectrum of medical conditions.

Muscle tissue engineering is a promising therapeutic strategy for volumetric muscle loss (VML). Among them, decellularized extracellular matrix (dECM) biological scaffolds have shown certain effects in restoring muscle function. However, researchers have inconsistent or even contradictory results on whether dECM biological scaffolds can efficiently regenerate muscle fibers and restore muscle function. This suggests that therapeutic strategies based on dECM biological scaffolds need to be further optimized and developed. In this study, we used a recellularization method of perfusing adipose-derived stem cells (ASCs) and L6 into adipose dECM (adECM) through vascular pedicles. On one hand, this strategy ensures sufficient quantity and uniform distribution of seeded cells inside scaffold. On the other hand, auxiliary L6 cells addresses the issue of low myogenic differentiation efficiency of ASCs. Subsequently, the treatment of VML animal experiments showed that the combined recellularization strategy can improve muscle regeneration and angiogenesis than the single ASCs recellularization strategy, and the TA of former had greater muscle contraction strength. Further single-nucleus RNA sequencing (snRNA-seq) analysis found that L6 cells induced ASCs transform into a new subpopulation of cells highly expressing Mki67, CD34 and CDK1 genes, which had stronger ability of oriented myogenic differentiation. This study demonstrates that co-seeding ASCs and L6 cells through vascular pedicles is a promising recellularization strategy for adECM biological scaffolds, and the engineered muscle tissue constructed based on this has significant therapeutic effects on VML. Overall, this study provides a new paradigm for optimizing and developing dECM-based therapeutic strategies.

Stem cells exhibit pluripotency and self-renewal abilities. Adipose-derived mesenchymal stem cells can potentially be used to reconstruct various tissues. They possess significant versatility and alleviate various aging-related diseases. Unfortunately, aging leads to senescence, apoptosis, and a decline in regenerative capacity in adipose-derived mesenchymal stem cells. These changes necessitate a strategy to mitigate the effects of aging on stem cells. Ohwia caudata (O. caudata) has therapeutic effects against several illnesses. However, studies on whether O. caudata has therapeutic effects against aging are lacking. In this study, we aimed to identify potential therapeutic anti-aging effects in the crude aqueous extract of O. caudata on adipose-derived mesenchymal stem cells. Using 0.1 μM doxorubicin, we induced aging in human adipose-derived mesenchymal stem cells (hADMSCs) and evaluated whether various concentrations of O. caudata aqueous extract exhibit anti-aging effects on them. The O. caudata extract exhibited significant antioxidant effects on hADMSCs without any toxicity. Furthermore, after treatment with the O. caudata aqueous extract, the levels of mitochondrial superoxide, DNA double-strand breaks, and telomere shortening were reduced in the hADMSCs subjected to doxorubicin-induced aging. The extract also suppressed doxorubicin-induced aging by upregulating klotho and downregulating p21 in hADMSCs. These findings indicated that the O. caudata extract exhibited anti-aging properties that modulated hADMSC homeostasis. Therefore, it could be a potential candidate for restoring the self-renewal ability and multipotency of aging hADMSCs.

Clinical and basic science applications using adipose-derived stem cells (ADSCs) are gaining popularity. The current adipose tissue harvesting procedures introduce nonphysiological conditions, which may affect the overall performance of the isolated ADSCs. In this study, we elucidate the differences between ADSCs isolated from adipose tissues harvested within the first 5 min of the initial surgical incision (well-vascularized, nonpremedicated condition) versus those isolated from adipose tissues subjected to medications and deprived of blood supply during elective free flap procedures (ischemic condition). ADSCs isolated from well-vascularized and ischemic tissues positively immunostained for several standard stem cell markers. Interestingly, the percent change in the CD36 expression for ADSCs isolated from ischemic versus well-vascularized tissue was significantly lower in males than females (p < 0.05). Upon differentiation and maturation to adipocytes, spheroids formed using ADSCs isolated from ischemic adipose tissue had lower triglyceride content compared to those formed using ADSCs isolated from the well-vascularized tissue (p < 0.05). These results indicate that ADSCs isolated from ischemic tissue either fail to uptake fatty acids or fail to efficiently convert those fatty acids into triglycerides. Therefore, more robust ADSCs suitable to establish in vitro adipose tissue models can be obtained by harvesting well-vascularized and nonpremedicated adipose tissues.

Although previous clinical studies have reported that cell-assisted lipotransfer increases the fat survival rate in facial fat transplants, most were case studies without quantitative evaluation. A multicenter randomized controlled study was performed to evaluate the safety and efficacy of the stromal vascular fraction (SVF) in facial fat grafts.

Twenty-three participants were enrolled for autologous fat transfer in the face, and assigned randomly to the experimental ( n = 11) or control ( n = 12) group. Fat survival was assessed using magnetic resonance imaging at 6 and 24 weeks postoperatively. Subjective evaluations were performed by the patients and surgeons. To address safety concerns, results of an SVF culture and the postoperative complications were recorded.

The overall fat survival rate was significantly higher in the experimental group than in the control group (6 weeks, 74.5% ± 9.99% versus 66.55% ± 13.77%, P < 0.025; 24 weeks, 71.27% ± 10.43% versus 61.98% ± 13.46%, P < 0.012). Specifically, graft survival in the forehead was 12.82% higher in the experimental group when compared with that in the control group at 6 weeks ( P < 0.023). Furthermore, graft survival in the forehead ( P < 0.021) and cheeks ( P < 0.035) was superior in the experimental group at 24 weeks. At 24 weeks, the aesthetic scores given by the surgeons were higher in the experimental group than in the control group ( P < 0.03); however, no significant intergroup differences were noted in the patient-evaluated scores. Neither bacterial growth from SVF cultures nor postoperative complications were noted.

SVF enrichment for autologous fat grafting can be a safe and effective technique for increasing the fat retention rate.

Therapeutic, II.

Mesenchymal stem cells (MSCs) are of great interest in cell therapies due to the immunomodulatory and other effects they have after autologous or allogeneic transplantation. In most clinical applications, a high number of MSCs is required; therefore, the isolated MSC population must be expanded in the cell culture until the desired number is reached. Analysing freshly isolated MSCs is challenging due to their rareness and heterogeneity, which is noticeable among donors, tissues, and cell subpopulations. Although the phenotype of MSCs in tissue can differ from those of cultured cells, phenotyping and counting are usually performed only after MSC proliferation. As MSC applicability is a developing and growing field, there is a need to implement phenotyping and counting methods for freshly isolated MSCs, especially in new one-step procedures where isolated cells are implanted immediately without cell culturing. Only by analysing harvested cells can we correctly evaluate such studies. This review describes multilevel heterogeneity and concentrations of MSCs and different strategies for phenotype determination and enumeration of freshly isolated MSCs.

The purpose of this systematic review was to analyze the current use of adipose-derived mesenchymal stem cells (ADMSCs) and present the available evidence on their therapeutic potential in the treatment of ankle orthopedic issues, evaluating the applications and results. A literature search of PubMed, Google Scholar, EMBASE and Cochrane Library database was performed. The review was conducted following PRISMA guidelines. Risk of bias assessment was conducted through the Methodological Index for Non-Randomized Studies (MINORS) criteria. Initial search results yielded 4348 articles. A total of 8 articles were included in the review process. No clinical evidence has demonstrated the effectiveness of one isolation method over the other, but nonenzymatic mechanical method has more advantages. In all studies included significant clinical outcomes improvement were recorded in patients affected by osteochondral lesion and osteoarthritis of ankle. All studies performed a concomitant procedure. No serious complications were reported. ADMSC injection, especially through the nonenzymatic mechanical methods, looks to be simple and promising treatment for osteochondral lesions and osteoarthritis of the ankle, with no severe complications. The current scarcity of studies and their low-quality level preclude definitive conclusions presently. LEVEL OF EVIDENCE: III.

The adipose-derived stem cells (ASCs) are a valuable resource for regenerative medicine and essential materials for research in fat deposition. However, the isolation procedure of ASCs has not been standardized and needs to be harmonized; differences in proliferation and adipogenic differentiation of ASCs obtained from different fat depots have not been well characterized. In the present study, we compared the efficiency of ASCs isolation by enzymatic treatment and explant culture methods and the proliferation ability and adipogenic differentiation potential of ASCs isolated from subcutaneous and visceral fat depots. The explant culture method was simple and with no need for expensive enzymes while the enzymatic treatment method was complex, time consuming and costly. By the explant culture method, a larger number of ASCs were isolated from subcutaneous and visceral fat depots. By contrast, fewer ASCs were obtained by the enzymatic treatment method, especially from visceral adipose. ASCs isolated by the explant culture method performed well in cell proliferation and adipogenic differentiation, though they were slightly lower than those by the enzymatic treatment method. ASCs isolated from visceral depot demonstrated higher proliferation ability and adipogenic differentiation potential. In total, the explant culture method is simpler, more efficient, and lower cost than the enzymatic treatment method for ASCs isolation; compared with visceral adipose, subcutaneous adipose is easier to isolate ASCs; however, the visceral ASCs are superior to subcutaneous ASCs in proliferation and adipogenic differentiation.

Obtaining accurate and reliable gene expression results in real-time RT-PCR (qRT-PCR) data analysis requires appropriate normalization by carefully selected reference genes, either a single or a combination of multiple housekeeping genes (HKGs). The optimal reference gene/s for normalization should demonstrate stable expression across varying conditions to diminish potential influences on the results. Despite the extensive database available, research data are lacking regarding the most appropriate HKGs for qRT-PCR data analysis in rabbit and horse adipose-derived stem cells (ASCs). Therefore, in our study, we comprehensively assessed and compared the suitability of some widely used HKGs, employing RefFinder and NormFinder, two extensively acknowledged algorithms for robust data interpretation. The rabbit and horse ASCs were obtained from subcutaneous stromal vascular fraction. ASCs were induced into tri-lineage differentiation, followed by the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) treatment of the adipose-differentiated rabbit ASCs, while horse experimental groups were formed based on adipogenic, osteogenic, and chondrogenic differentiation. At the end of the experiment, the total mRNA was obtained and used for the gene expression evaluation of the observed factors. According to our findings, glyceraldehyde 3-phosphate dehydrogenase was identified as the most appropriate endogenous control gene for rabbit ASCs, while hypoxanthine phosphoribosyltransferase was deemed most suitable for horse ASCs. The obtained results underscore that these housekeeping genes exhibit robust stability across diverse experimental conditions, remaining unaltered by the treatments. In conclusion, the current research can serve as a valuable baseline reference for experiments evaluating gene expression in rabbit and horse ASCs. It highlights the critical consideration of housekeeping gene abundance and stability in qPCR experiments, emphasizing the need for an individualized approach tailored to the specific requirements of the study.

COVID-19 emerged in December 2019 in Wuhan, China, spread worldwide rapidly, and caused millions of deaths in a short time. Many preclinical and clinical studies were performed to discover the most efficient therapy to reduce the mortality of COVID-19 patients. Among various approaches for preventing and treating COVID-19, mesenchymal stem cell (MSC) therapy can be regarded as a novel and efficient treatment for managing COVID-19 patients. In this review, we explain the pathogenesis of COVID-19 infection in humans and discuss the role of MSCs in suppressing the inflammation and cytokine storm produced by COVID-19. Then, we reviewed the clinical trial and systematic review studies that investigated the safety and efficacy of MSC therapy in the treatment of COVID-19 infection.

Background: Regenerative medicine is evolving with discoveries like the stromal vascular fraction (SVF), a diverse cell group from adipose tissue with therapeutic promise. Originating from fat cell metabolism studies in the 1960s, SVF's versatility was recognized after demonstrating multipotency. Comprising of cells like pericytes, smooth muscle cells, and, notably, adipose-derived stem cells (ADSCs), SVF offers tissue regeneration and repair through the differentiation and secretion of growth factors. Its therapeutic efficacy is due to these cells' synergistic action, prompting extensive research. Methods: This review analyzed the relevant literature on SVF, covering its composition, action mechanisms, clinical applications, and future directions. An extensive literature search from January 2018 to June 2023 was conducted across databases like PubMed, Embase, etc., using specific keywords. Results: The systematic literature search yielded a total of 473 articles. Sixteen articles met the inclusion criteria and were included in the review. This rigorous methodology provides a framework for a thorough and systematic analysis of the existing literature on SVF, offering robust insights into the potential of this important cell population in regenerative medicine. Conclusions: Our review reveals the potential of SVF, a heterogeneous cell mixture, as a powerful tool in regenerative medicine. SVF has demonstrated therapeutic efficacy and safety across disciplines, improving pain, tissue regeneration, graft survival, and wound healing while exhibiting immunomodulatory and anti-inflammatory properties.

Biphasic calcium phosphates (BCP) may serve as off-the-shelf alternatives for iliac crest-derived autologous bone in alveolar cleft reconstructions. To add osteoinductivity to the osteoconductive BCPs to achieve similar regenerative capacity as autologous bone, a locally harvested buccal fat pad will be mechanically fractionated to generate microfragmented fat (MFAT), which has been shown to have high regenerative capacity due to high pericyte and mesenchymal stem cell content and a preserved perivascular niche.

Our primary objectives will be to assess the feasibility and safety of the BCP-MFAT combination. The secondary objective will be efficacy, which will be evaluated using radiographic imaging and histological and histomorphometric evaluation of biopsies taken 6 months postoperatively, concomitant with dental implant placement.

Eight patients with alveolar cleft (≥15 years) will be included in this prospective, nonblinded, first-in-human clinical study. MFAT will be prepared intraoperatively from the patient's own buccal fat pad. Regular blood tests and physical examinations will be conducted, and any adverse events (AEs) or serious EAs (SAEs) will be meticulously recorded. Radiographic imaging will be performed prior to surgery and at regular intervals after reconstruction of the alveolar cleft with the BCP-MFAT combination. Biopsies obtained after 6 months with a trephine drill used to prepare the implantation site will be assessed with histological and histomorphometric analyses after methylmethacrylate embedding and sectioning.

The primary outcome parameter will be safety after 6 months' follow-up, as monitored closely using possible occurrences of SAEs based on radiographic imaging, blood tests, and physical examinations. For efficacy, radiographic imaging will be used for clinical grading of the bone construct using the Bergland scale. In addition, bone parameters such as bone volume, osteoid volume, graft volume, and number of osteoclasts will be histomorphometrically quantified. Recruitment started in November 2019, and the trial is currently in the follow-up stage. This protocol's current version is 1.0, dated September 15, 2019.

In this first-in-human study, not only safety but also the histologically and radiographically assessed regenerative potential of the BCP-MFAT combination will be evaluated in an alveolar cleft model. When an SAE occurs, it will be concluded that the BCP-MFAT combination is not yet safe in the current setting. Regarding AEs, if they do not occur at a higher frequency than that in patients treated with standard care (autologous bone) or can be resolved by noninvasive conventional methods (eg, with analgesics or antibiotics), the BCP-MFAT combination will be considered safe. In all other cases, the BCP-MFAT combination will not yet be considered safe.

Indonesia Clinical Trial Registry INA-EW74C1N; https://tinyurl.com/28tnrr64.

DERR1-10.2196/42371.

The use of minimally manipulated adipose tissue (MM-AT) products is gaining increasing interest for the treatment of knee osteoarthritis (OA). MM-AT represents an easy way to exploit adipose tissue properties, although clinical evidence is still limited, as well as their benefits with respect to more documented orthobiologics like platelet-rich plasma (PRP). A systematic review and meta-analysis were performed to evaluate the safety and efficacy of MM-AT products for knee OA management. The risk of bias of the included studies was evaluated using the Dawns and Black checklist for all the included studies and RoB-2.0 for randomized controlled trials (RCTs). Thirty-three clinical studies were included in the qualitative analysis: 13 prospective case series, 10 retrospective case series, 7 RCTs, 2 retrospective comparative studies, and 1 prospective comparative study. An overall clinical improvement and few minor adverse events were observed. Five RCTs comparing MM-AT and PRP injections were meta-analyzed, showing comparable results. The analysis also highlighted the limits of the literature, with only a few high-level trials and an overall low quality. Even though the current literature is still limited, the available evidence suggests the safety and overall positive results of the intra-articular injections of MM-AT products for knee OA treatment.

Worldwide, osteoporosis is the utmost predominant degenerative bone condition. Stem cell regenerative therapy using adipose-derived mesenchymal stem cells (ADMSCs) is a promising therapeutic route for osteoporosis. Photobiomodulation (PBM) has sparked considerable international appeal due to its' ability to augment stem cell proliferation and differentiation properties. Furthermore, the differentiation of ADMSCs into osteoblast cells and cellular proliferation effects have been established using a combination of osteogenic differentiation inducers and PBM. This in vitro study applied dexamethasone, β-glycerophosphate disodium, and ascorbic acid as differentiation inducers for osteogenic induction differentiation media. In addition, PBM at a near-infrared (NIR) wavelength of 825 nm, a green (G) wavelength of 525 nm, and the novel combination of both these wavelengths using a single fluence of 5 J/cm2 had been applied to stimulate proliferation and differentiation effectivity of immortalised ADMSCs into early osteoblasts. Flow cytometry and ELISA were used to identify osteoblast antigens using early and late osteoblast protein markers. Alizarin red Stain was employed to identify calcium-rich deposits by cells within culture. The morphology of the cells was examined, and biochemical assays such as an EdU proliferation assay, MTT proliferation and viability assay, Mitochondrial Membrane Potential assay, and Reactive Oxygen Species assay were performed. The Central Scratch Test determined the cells' motility potential. The investigative outcomes revealed that a combination of PBM treatment and osteogenic differentiation inducers stimulated promising early osteogenic differentiation of immortalised ADMSCs. The NIR-Green PBM combination did appear to offer great potential for immortalised ADMSC differentiation into early osteoblasts amongst selected assays, however, further investigations will be required to establish the effectivity of this novel wavelength combination. This research contributes to the body of knowledge and assists in the establishment of a standard for osteogenic differentiation in vitro utilising PBM.

Background and Objectives: Knee osteoarthritis (OA) is a widespread joint disease, set to increase due to aging and rising obesity. Beyond cartilage degeneration, OA involves the entire joint, including the synovial fluid, bones, and surrounding muscles. Existing treatments, such as NSAIDs and corticosteroid injections, mainly alleviate symptoms but can have complications. Joint replacement surgeries are definitive but carry surgical risks and are not suitable for all. Stromal vascular fraction (SVF) therapy is a regenerative approach using cells from a patient's adipose tissue. SVF addresses as degenerative and inflammatory aspects, with potential for cartilage formation and tissue regeneration. Unlike traditional treatments, SVF may reverse OA changes. Being autologous, it reduces immunogenic risks. Materials and Methods: A systematic search was undertaken across PubMed, Medline, and Scopus for relevant studies published from 2017 to 2023. Keywords included "SVF", "Knee Osteoarthritis", and "Regenerative Medicine". Results: This systematic search yielded a total of 172 articles. After the removal of duplicates and an initial title and abstract screening, 94 full-text articles were assessed for eligibility. Of these, 22 studies met the inclusion criteria and were subsequently included in this review. Conclusions: This review of SVF therapy for knee OA suggests its potential therapeutic benefits. Most studies confirmed its safety and efficacy, and showed improved clinical outcomes and minimal adverse events. However, differences in study designs and sizes require a careful interpretation of the results. While evidence supports SVF's positive effects, understanding methodological limitations is key. Incorporating SVF is promising, but the approach should prioritize patient safety and rigorous research.

To what extent does regenerative medicine with stem cell therapy help to address infertility issues for future clinical application?

Regenerative medicine using different stem cell sources is yielding promising results in terms of protecting the ovarian reserve from damage and senescence, and improving fertility potential in various preclinical settings.

Regenerative medicine using stem cell therapy is emerging as a potential strategy to address a number of issues in the field of human reproduction. Indeed, different types of adult and fetal mesenchymal stem cells (MSCs) have been tested with promising results, owing to their ability to differentiate into different tissue lineages, move toward specific injured sites (homing), and generate a secretome with wound-healing, proangiogenic, and antioxidant capacities.

Guided by the checklist for preferred reporting items for systematic reviews and meta-analyses, we retrieved relevant studies from PubMed, Medline, and Embase databases until June 2023 using the following keywords: 'mesenchymal stem cells' AND 'ovarian follicles' OR 'ovarian tissue culture' OR 'ovarian follicle culture' OR 'cumulus oocyte complex'. Only peer-reviewed published articles written in English were included.

The primary outcome for the experimental strategies was evaluation of the ovarian reserve, with a focus on follicle survival, number, and growth. Secondary outcomes involved analyses of other parameters associated with the follicle pool, such as hormones and growth factors, ovarian tissue viability markers including oxidative stress levels, oocyte growth and maturation rates, and of course pregnancy outcomes.

Preclinical studies exploring MSCs from different animal origins and tissue sources in specific conditions were selected (n = 112), including: in vitro culture of granulosa cells, ovarian tissue and isolated ovarian follicles; ovarian tissue transplantation; and systemic or intraovarian injection after gonadotoxic or age-related follicle pool decline. Protecting the ovarian reserve from aging and gonadotoxic damage has been widely tested in vitro and in vivo using murine models and is now yielding initial data in the first ever case series of patients with premature ovarian insufficiency. Use of MSCs as feeder cells in ovarian tissue culture was found to improve follicle outcomes and oocyte competence, bringing us one step closer to future clinical application. MSCs also have proved effective at boosting revascularization in the transplantation site when grafting ovarian tissue in experimental animal models.

While preclinical results look promising in terms of protecting the ovarian reserve in different experimental models (especially those in vitro using various mammal experimental models and in vivo using murine models), there is still a lot of work to do before this approach can be considered safe and successfully implemented in a clinical setting.

All gathered data on the one hand show that regenerative medicine techniques are quickly gaining ground among innovative techniques being developed for future clinical application in the field of reproductive medicine. After proving MSC effectiveness in preclinical settings, there is still a lot of work to do before MSCs can be safely and effectively used in different clinical applications.

This study was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (FNRS-PDR T.0077.14, FNRS-CDR J.0063.20, and grant 5/4/150/5 awarded to Marie-Madeleine Dolmans), Fonds Spéciaux de Recherche, and the Fondation St Luc. None of the authors have any competing interest to disclose.

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Temporomandibular joint (TMJ) arthritis is a debilitating, challenging condition and different methods have been implicated for its treatment. This study aimed to test the therapeutic potentials of low-level laser therapy (LLLT) associated with adipose derived stem cells (ADSC) or their derived secretome on a murine model induced arthritis.

Forty eight rats were divided into four groups where group I was the sham control, the rest of animals were subjected to arthritis induction using complete Freund's adjuvant, then divided as follows: group II received phosphate buffered saline (PBS) intraarticular injection and irradiation of 0 j/cm2, group III received ADSCs derived secretome and irradiation of 38 j/cm2, and group IV received ADSCs and irradiation of 38 j/cm2 as well. One and three weeks after treatment, animals were euthanized, and paraffin blocks were processed for histological assessment by hematoxylin and eosin stain with histomorphometrical analysis. Histochemical evaluation of joint proteoglycan content was performed through toluidine blue stain, and immunohistochemical staining by the proinflammatory marker tumor necrosis factor-α (TNF-α) was performed followed by the relevant statistical tests.

The arthritis group showed histological signs of joint injury including cartilage atrophy, articular disc fibrosis, irregular osteochondral interface, and condylar bone resorption together with high inflammatory reaction and defective proteoglycan content. In contrast, the treated groups III and IV showed much restoration of the joint structure with normal cartilage and disc thickness. The inflammation process was significantly suppressed especially after three weeks as confirmed by the significant reduction in TNF-α positive immunostaining compared to the arthritic group, and the cartilage proteoglycan content also showed significant increase relative to the arthritic group. However, no significant difference between the results of the two treated groups was detected.

LLLT conjugated with ADSCs or ADSCs derived secretome can efficiently enhance the healing of arthritic TMJs. Stem cell secretome can be applied as a safe, potent therapy. However, further investigations are required to unravel its mechanism of action and pave its way as a safe, novel, cell free therapy.

Bovine mesenchymal stromal cells (MSCs) display important features that render them valuable for cell therapy and tissue engineering strategies, such as self-renewal, multi-lineage differentiation, as well as immunomodulatory properties. These cells are also promising candidates to produce cultured meat. For all these applications, it is imperative to unequivocally identify this cell population. The isolation and in vitro tri-lineage differentiation of bovine MSCs is already described, but data on their immunophenotypic characterization is not yet complete. The currently limited availability of monoclonal antibodies (mAbs) specific for bovine MSC markers strongly hampers this research. Following the minimal criteria defined for human MSCs, bovine MSCs should express CD73, CD90, and CD105 and lack expression of CD14 or CD11b, CD34, CD45, CD79α, or CD19, and MHC-II. Additional surface proteins which have been reported to be expressed include CD29, CD44, and CD106. In this study, we aimed to immunophenotype bovine adipose tissue (AT)-derived MSCs using multi-color flow cytometry. To this end, 13 commercial Abs were screened for recognizing bovine epitopes using the appropriate positive controls. Using flow cytometry and immunofluorescence microscopy, cross-reactivity was confirmed for CD34, CD73, CD79α, and CD90. Unfortunately, none of the evaluated CD105 and CD106 Abs cross-reacted with bovine cells. Subsequently, AT-derived bovine MSCs were characterized using multi-color flow cytometry based on their expression of nine markers. Bovine MSCs clearly expressed CD29 and CD44, and lacked expression of CD14, CD45, CD73, CD79α, and MHCII, while a variable expression was observed for CD34 and CD90. In addition, the mRNA transcription level of different markers was analyzed using reverse transcription quantitative polymerase chain reaction. Using these panels, bovine MSCs can be properly immunophenotyped which allows a better characterization of this heterogenous cell population.

Mechanical isolation of the stromal vascular fraction (SVF) separates the stromal component from the parenchymal cells. Emulsification is currently the most commonly used disaggregation method and is effective in disrupting adipocytes and fragmenting the extracellular matrix (ECM). Subsequent push-through filtration of emulsified adipose tissue removes parts of the ECM that are not sufficiently micronized, thereby further liquifying the tissue.

The aim of this study was to investigate whether filtration over a 500-µm mesh filter might affect the SVF and adipose-derived mesenchymal stem cell (MSC) quantity in emulsified lipoaspirate samples by removing ECM fragments.

Eleven lipoaspirate samples from healthy nonobese women were harvested and emulsified in 30 passes. One-half of the sample was filtered through a 500-µm mesh filter and the other half was left unfiltered. Paired samples were processed and analyzed by flow cytometry to identify cellular viability, and SVF and MSC yield.

Push-through filtration reduced the number of SVF cells by a mean [standard deviation] of 39.65% [5.67%] (P < .01). It also significantly reduced MSC counts by 48.28% [6.72%] (P < .01). Filtration did not significantly affect viability (P = .118).

Retention of fibrous remnants by push-through filters removed ECM containing the SVF and MSCs from emulsified lipoaspirates. Processing methods should aim either to further micronize the lipoaspirate before filtering or not to filter the samples at all, to preserve both the cellular component carried within the ECM and the inductive properties of the ECM itself.

Autologous fat transplantation -i.e., lipofilling- has become a promising and popular technique in aesthetic and reconstructive surgery with several application such as breast reconstruction, facial and hand rejuvenation. However, the use of this technology is still limited due to an unpredictable and low graft survival rate (which ranges from 25%-80%). A systematic literature review was performed by thoroughly searching 12 terms using the PubMed database. The objective of this study is to present the current evidence for the efficacy of adjuvant regenerative strategies and cellular factors, which have been tested to improve fat graft retention. We present the main results (fat retention rate, histological analysis for pre-clinical studies and satisfaction/ complication for clinical studies) obtained from the studies of the three main fat grafting enrichment techniques: platelet-rich plasma (PRP), the stromal vascular fraction (SVF) and adipose-derived stem cells (ADSCs) and discuss the promising role of recent angiogenic cell enrichment that could induce early vascularization of fat graft. All in all, adding stem or progenitor cells to autologous fat transplantation might become a new concept in lipofilling. New preclinical models should be used to find mechanisms able to increase fat retention, assure safety and transfer these technologies to a good manufacturing practice (GMP) compliant facility, to manufacture an advanced therapy medicinal product (ATMP).

Adipose-derived stem cells (ADSCs) are isolated from abundant adipose tissue and have the capacity to differentiate into multiple cell lineages. ADSCs have raised big interest in therapeutic applications in regenerative medicine and demonstrated to fulfill the criteria for a successful cell therapy. There are several methods for isolation of ADSCs from adipose tissue and cryopreservation of ADSCs. Here, novel methods for the isolation and cryopreservation of ADSCs are presented and focused. Microscopic pieces of adipose tissue were placed on transwell inserts, and the ADSCs were induced to migrate to the lower wells for 1 week. We compared the properties of our ADSCs with those isolated by enzymatic digestion and enzyme-free method of culture plate, and our ADSCs were found to be more stable and healthier. In addition, we proposed a novel cryoprotectant solution (FNCP) containing pectin and L-alanine, which was compared with standard cryoprotectant solution. Overall, our methods proved more useful for ADSCs isolation than other methods and did not require consideration of "minimal manipulation" by the U.S. Food and Drug Administration (FDA). Furthermore, our FNCP did not contain dimethyl sulfoxide and fetal bovine serum, therefore stable storage is possible in xeno-free and animal-free cryopreservation solutions.

Cell therapy for adrenal insufficiency is a potential method for physiological glucocorticoid and mineralocorticoid replacement. We have previously shown that mouse mesenchymal stromal cells (MSCs) differentiated into steroidogenic cells by the viral vector-mediated overexpression of nuclear receptor subfamily 5 group A member 1 (NR5A1), an essential regulator of steroidogenesis, and their implantation extended the survival of bilateral adrenalectomized (bADX) mice.

In this study, we examined the capability of NR5A1-induced steroidogenic cells prepared from human adipose tissue-derived MSCs (MSC [AT]) and the therapeutic effect of the implantation of human NR5A1-induced steroidogenic cells into immunodeficient bADX mice.

Human NR5A1-induced steroidogenic cells secreted adrenal and gonadal steroids and exhibited responsiveness to adrenocorticotropic hormone and angiotensin II in vitro. In vivo, the survival time of bADX mice implanted with NR5A1-induced steroidogenic cells was significantly prolonged compared with that of bADX mice implanted with control MSC (AT). Serum cortisol levels, which indicate hormone secretion from the graft, were detected in bADX mice implanted with steroidogenic cells.

This is the first report to demonstrate steroid replacement by the implantation of steroid-producing cells derived from human MSC (AT). These results indicate the potential of human MSC (AT) to be a source of steroid hormone-producing cells.

Adipose tissue is recognized as the major endocrine organ, potentially acting as a source of mesenchymal stem cells for various applications in regenerative medicine. Athletic horses are often exposed to traumatic injuries, resulting in severe financial losses. The development of adipose-derived stem cells' regenerative potential depends on many factors. The extraction of stem cells from subcutaneous adipose tissue is non-invasive, non-traumatic, cheaper, and safer than other sources. Since there is a lack of unique standards for identification, the isolated cells and applied differentiation protocols are often not species-specific; therefore, the cells cannot reveal their multipotent properties, so their stemness features remain questionable. The current review discusses some aspects of the specificity of equine adipose stem cells concerning their features, immunophenotyping, secretome profile, differentiation abilities, culturing conditions, and consequent possibilities for clinical application in concrete disorders. The presented new approaches elucidate the possibility of the transition from cell-based to cell-free therapy with regenerative purposes in horses as an alternative treatment to cellular therapy. In conclusion, their clinical benefits should not be underestimated due to the higher yield and the physiological properties of adipose-derived stem cells that facilitate the healing and tissue regeneration process and the ability to amplify the effects of traditional treatments. More profound studies are necessary to apply these innovative approaches when treating traumatic disorders in racing horses.

A large part of mesenchymal stromal cell (MSC) regenerative and immunomodulatory action is mediated by paracrine signaling. Hence, an increasing body of evidence acknowledges the potential of MSC secretome in a variety of preclinical and clinical scenarios. Mid-term serum deprivation is a common approach in the pipeline of MSC secretome production. Nevertheless, up to now, little is known about the impact of this procedure on the metabolic status of donor cells.

Here, through untargeted differential metabolomics, we revealed an impairment of mitochondrial metabolism in adipose-derived MSCs exposed for 72 h to serum deprivation.

This evidence was further confirmed by the significant accumulation of reactive oxygen species and the reduction of succinate dehydrogenase activity. Probably as a repair mechanism, an upregulation of mitochondrial superoxide dismutase was also induced.

Of note, the analysis of mitochondrial functionality indicated that, despite a significant reduction of basal respiration and ATP production, serum-starved MSCs still responded to changes in energy demand. This metabolic phenotype correlates with the obtained evidence of mitochondrial elongation and branching upon starvation.

Hypertension is a major risk factor for cardiovascular diseases, such as strokes and myocardial infarctions. Nearly 70% of hypertension onsets in adults can be attributed to obesity, primarily due to sympathetic overdrive and the dysregulated renin-angiotensin system. Sympathetic overdrive increases vasoconstriction via α1-adrenoceptor activation on vascular cells. Despite the fact that a sympathetic outflow increases in individuals with obesity, as a rule, there is a cohort of patients with obesity who do not develop hypertension. In this study, we investigated how adrenoceptors' expression and functioning in adipose tissue are affected by obesity-driven hypertension. Here, we demonstrated that α1A is a predominant isoform of α1-adrenoceptors expressed in the adipose tissue of patients with obesity, specifically by multipotent mesenchymal stromal cells (MSCs). These cells respond to prolonged exposure to noradrenaline in the model of sympathetic overdrive through the elevation of α1A-adrenoceptor expression and signaling. The extent of MSCs' response to noradrenaline correlates with a patient's arterial hypertension. scRNAseq analysis revealed that in the model of sympathetic overdrive, the subpopulation of MSCs with contractile phenotype expanded significantly. Elevated α1A-adrenoceptor expression is triggered specifically by beta3-adrenoceptors. These data define a novel pathophysiological mechanism of obesity-driven hypertension by which noradrenaline targets MSCs to increase microvessel constrictor responsivity.

Osteoarthritis (OA) is the most common joint disorder, is associated with an increasing socioeconomic impact owing to the ageing population.

To analyze and compare the efficacy and safety of bone-marrow-derived mesenchymal stromal cells (BM-MSCs) and adipose tissue-derived MSCs (AD-MSCs) in knee OA management from published randomized controlled trials (RCTs).

Independent and duplicate electronic database searches were performed, including PubMed, EMBASE, Web of Science, and Cochrane Library, until August 2021 for RCTs that analyzed the efficacy and safety of AD-MSCs and BM-MSCs in the management of knee OA. The visual analog scale (VAS) score for pain, Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), Lysholm score, Tegner score, magnetic resonance observation of cartilage repair tissue score, knee osteoarthritis outcome score (KOOS), and adverse events were analyzed. Analysis was performed on the R-platform using OpenMeta (Analyst) software. Twenty-one studies, involving 936 patients, were included. Only one study compared the two MSC sources without patient randomization; hence, the results of all included studies from both sources were pooled, and a comparative critical analysis was performed.

At six months, both AD-MSCs and BM-MSCs showed significant VAS improvement (P = 0.015, P = 0.012); this was inconsistent at 1 year for BM-MSCs (P < 0.001, P = 0.539), and AD-MSCs outperformed BM-MSCs compared to controls in measures such as WOMAC (P < 0.001, P = 0.541), Lysholm scores (P = 0.006; P = 0.933), and KOOS (P = 0.002; P = 0.012). BM-MSC-related procedures caused significant adverse events (P = 0.003) compared to AD-MSCs (P = 0.673).

Adipose tissue is superior to bone marrow because of its safety and consistent efficacy in improving pain and functional outcomes. Future trials are urgently warranted to validate our findings and reach a consensus on the ideal source of MSCs for managing knee OA.

Cite this article: Bone Joint Res 2023;12(1):5-8.

Neurological disorders are recognized as major causes of death and disability worldwide. Because of this, they represent one of the largest public health challenges. With awareness of the massive burden associated with these disorders, came the recognition that treatment options were disproportionately scarce and, oftentimes, ineffective. To address these problems, modern research is increasingly looking into novel, more effective methods to treat neurological patients; one of which is cell-based therapies. In this review, we present a critical analysis of the features, challenges, and prospects of one of the stem cell types that can be employed to treat numerous neurological disorders-mesenchymal stem cells (MSCs). Despite the fact that several studies have already established the safety of MSC-based treatment approaches, there are still some reservations within the field regarding their immunocompatibility, heterogeneity, stemness stability, and a range of adverse effects-one of which is their tumor-promoting ability. We additionally examine MSCs' mechanisms of action with respect to in vitro and in vivo research as well as detail the findings of past and ongoing clinical trials for Parkinson's and Alzheimer's disease, ischemic stroke, glioblastoma multiforme, and multiple sclerosis. Finally, this review discusses prospects for MSC-based therapeutics in the form of biomaterials, as well as the use of electromagnetic fields to enhance MSCs' proliferation and differentiation into neuronal cells.

Mesenchymal stem cells are currently used to treat several diseases. Populations of putative stem cells found in the adipose tissue (ASCs) have been shown to possess particularly enhanced functionalities. Nonetheless, there is lack of evidence that evaluates the effects of cryopreservation techniques on well-defined functional ASC populations characterized by immunophenotypical repertoire.

We therefore embarked a study to compare the frozen-thawed ASC subsets: CD73+CD90+CD105+CD34+CD146-(CD34+CD146), CD73+CD90+CD105+CD34+CD146+(CD34+CD146+), and CD73+CD90+CD105+CD34+(CD34+). We assessed their characterization in different functional assays.

The ASC immunophenotypical subsets-purified by a flow cytometry sorting technique-were frozen in liquid nitrogen. After a period, they were thawed to examine their differentiation ability, colony-forming units, viability, and growth rate.

We confirmed that inside the primary cell culture system, the proportion of CD34+, CD34+CD146-, and CD34+CD146+ took up 80%, 62%, and 19% on average, respectively. All populations could be frozen and stored in liquid nitrogen with retention of more than 85% of cell viability and displayed comparable stemness characteristics. Most importantly, the CD34+CD146+ subpopulation displayed a higher proliferation rate than other groups.

Our data demonstrated that the frozen-thawed CD34+CD146+ cells might represent a promising source for autologous cellular-based therapy. These findings set the basis for ASC subpopulations-based application in future potential clinical settings.