MSC-conditioned Medium Research Articles

Mesenchymal stem cell application for treatment of neuroinflammation-induced cognitive impairment in mice.

Background: The present research has been undertaken to study the therapeutic potential of mesenchymal stem cells (MSCs) for the treatment of neuroinflammation-induced cognitive disorders. Methods: Either umbilical cord or adipose MSCs were injected into mice treated with lipopolysaccharide. The mice were studied in behavioral tests, and their brains were examined by means of immunohistochemistry, electron microscopy and sandwich ELISA. Results: MSCs, introduced either intravenously or intraperitoneally, restored episodic memory of mice disturbed by inflammation, normalized nAChR and Aβ1-42 levels and stimulated proliferation of neural progenitor cells in the brain. The effect of MSCs was observed for months, whereas that of MSC-conditioned medium was transient and stimulated an immune reaction. SDF-1α potentiated the effects of MSCs on the brain and memory. Conclusion: MSCs of different origins provide a long-term therapeutic effect in the treatment of neuroinflammation-induced episodic memory impairment.

Efficacy of Microneedling Combined With Local Application of Human Umbilical Cord-Derived Mesenchymal Stem Cells Conditioned Media in Skin Brightness and Rejuvenation: A Randomized Controlled Split-Face Study.

BackgroundFighting skin aging signs is one of the major challenges of the 21st century, recently, mesenchymal stem cells (MSCs) and microneedling (MN) have been applied for anti-aging. This study aims to evaluate the efficacy of the combination of MN and human umbilical cord-derived mesenchymal stem cells conditioned media (hUC-MSCs-CM) in skin brightness and rejuvenation.MethodsThirty volunteers with facial skin aging were recruited for the randomized, controlled split-face study. The left and right sides of the face were randomly applied with saline via MN or hUC-MSCs-CM via MN. Five sessions were performed for each volunteer at 2-week intervals. Two dermatologists evaluated the clinical improvement, in terms of skin brightness and texture. A satisfaction score based on a self-evaluation questionnaire was recorded at 2 weeks after the last treatment. The objective evaluation was recorded before the first treatment, and at 2 weeks after the last treatment.ResultsTwenty-eight volunteers with a mean (SD) age of 41 (6.54) years old completed the trial. The investigator’s assessment for skin brightness and texture, and the self-satisfaction score revealed statistically better effects in hUC-MSCs-CM -plus-MN group than in MN alone (MN saline) group. No severe side effects were reported during the whole study period. Compared to MN alone group, the objective assessment revealed significant improvements in skin brightness (reduced melanin index, ultraviolet spots, and brown spots) and skin texture (reduced wrinkles and pores, and increased skin elasticity) in hUC-MSCs-CM-plus-MN group, while there were no obvious differences in skin hydration, trans-epidermal water loss, and the erythema index.ConclusionThe combination of hUC-MSCs-CM and MN exhibite anti-aging efficacy, and this could be used for facial rejuvenation in the future.

Bone Marrow MSC Secretome Increases Equine Articular Chondrocyte Collagen Accumulation and Their Migratory Capacities.

Equine osteoarthritis (OA) leads to cartilage degradation with impaired animal well-being, premature cessation of sport activity, and financial losses. Mesenchymal stem cell (MSC)-based therapies are promising for cartilage repair, but face limitations inherent to the cell itself. Soluble mediators and extracellular vesicles (EVs) secreted by MSCs are the alternatives to overcome those limitations while preserving MSC restorative properties. The effect of equine bone marrow MSC secretome on equine articular chondrocytes (eACs) was analyzed with indirect co-culture and/or MSC-conditioned media (CM). The expression of healthy cartilage/OA and proliferation markers was evaluated in eACs (monolayers or organoids). In vitro repair experiments with MSC-CM were made to evaluate the proliferation and migration of eACs. The presence of nanosized EVs in MSC-CM was appraised with nanoparticle tracking assay and transmission electron microscopy. Our results demonstrated that the MSC secretome influences eAC phenotype by increasing cartilage functionality markers and cell migration in a greater way than MSCs, which could delay OA final outcomes. This study makes acellular therapy an appealing strategy to improve equine OA treatments. However, the MSC secretome contains a wide variety of soluble mediators and small EVs, such as exosomes, and further investigation must be performed to understand the mechanisms occurring behind these promising effects.

Umbilical cord-derived mesenchymal stem cell conditioned medium reverses neuronal oxidative injury by inhibition of TRPM2 activation and the JNK signaling pathway

BackgroundThe mechanism by which MSC-CM protects neuronal cells against ischemic injury remains to be elucidated. In this study, we aimed to clarify the protective effect of umbilical cord-derived mesenchymal stem cell conditioned medium (UC-MSC-CM) on neuronal oxidative injury and its potential mechanism.Methods and ResultsNeuronal oxidative damage was mimicked by H2O2 treatment of the HT22 cell line. The numbers of cleaved-Caspase-3-positive cells and protein expression of Caspase-9 induced by H2O2 treatment were decreased by UC-MSC-CM treatment. Furthermore, SOD protein expression was increased in the MSC-CM group compared with that in the H2O2 group. The H2O2-induced TRPM2-like currents in HT22 cells were attenuated by MSC-CM treatment. In addition, H2O2 treatment downregulated the expression of p-JNK protein in HT22 cells, and this the downward trend was reversed by incubation with MSC-CM.ConclusionsUC-MSC-CM protects neurons against oxidative injury, possibly by inhibiting activation of TRPM2 and the JNK signaling pathway.

Lipopolysaccharide-pretreated mesenchymal stem cell-conditioned medium optimized with 10 kDa filter attenuates the injury of H9c2 cardiomyocytes in a model of hypoxia/reoxygenation.

Mesenchymal stem cell-derived conditioned medium (MSC-CM) improves cardiac function, which is partly attributed to the released paracrine factors. Since such cardioprotection is moderate and transient, it is essential that MSC-CM's effective components are optimized to alleviate myocardial injury. To optimize MSC-CM, MSCs were treated with or without lipopolysaccharides (LPSs) for 48 h (serum-free), and the supernatant was collected. Then, LPS-CM (MSC stimulated by LPS) was further treated with LPS remover (LPS Re-CM) or was concentrated with a 10 kDa cutoff filter (10 kDa-CM). Enzyme-linked immunosorbent assay showed that all the pretreatments increased the levels of vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and insulin growth factor (IGF) except LPS Re-CM; 10 kDa-CM was superior to the other CMs. Cell Counting Kit-8 displayed that the viability of injured H9c2 cells was enhanced with the increase in the MSC-CM concentration. We also found that the 10 kDa-CM significantly alleviated H9c2 hypoxia/reoxygenation (H/R) injury, as evidenced by the increased Bcl-2/Bax ratio, and decreased the levels of lactate dehydrogenase and cardiac troponin. Transmission electron microscopy (TEM), TdT-mediated dUTP nick-end labelling (TUNEL), and hematoxylin and eosin staining (H&E) confirmed that 10 kDa-CM inhibited H/R-induced H9c2 morphological changes. Proteomic analysis identified 41 differentially expressed proteins in 10 kDa-CM, among which anti-inflammation, proangiogenesis, and antiapoptosis were related to cardiac protection. This study indicates that 10 kDa-CM protects H9c2 cardiomyocytes from H/R injury by preserving most of the protective factors, such as VEGF, HGF, and IGF, in MSC-CM.

A spray-filming, tissue-adhesive, and bioactive polysaccharide self-healing hydrogel for skin regeneration

Developing multifunctional self-healing hydrogels as wound dressings, including strong tissue adhesion, spray film-forming ability, and excellent bioactivity, are highly desired for full-thickness skin wound healing applications. In this study, chondroitin sulfate (CSA) was firstly oxidized to aldehyde-based chondroitin sulfate (OHC-CSA), and then dopamine (DA) was grafted onto OHC-CSA to form OHC-CSA-DA. Thereafter, the OHC-CSA-DA and carboxymethyl chitosan (COOH-CS) based hydrogel (CSA-DA-CS) was successfully fabricated through integrating enzymatic crosslinking, Schiff base and hydrogen bonding interactions. The optimum adhesive strength of the hydrogel was obtained by an orthogonal design when the concentrations of polymer, HRP enzyme, and H2O2 were 30 mg/mL, 0.24 U/mL, and 0.00085%, respectively. This novel hydrogel showed rapid self-healing performance, robust mechanical strength and strong adhesion, spray film-forming ability, hemostatic property, antibacterial property and good biocompatibility, which are beneficial to function as a wound dressing. Besides, the addition of mesenchymal stem cell-conditioned medium (CM) can further improve the biocompatibility and wound repair ability of the hydrogel.Therefore, this novel hydrogel is an outstanding wound dressing candidate for full-thickness wound healing.

Enhancing and stabilization of cord blood regulatory T-cell suppressive function by human mesenchymal stem cell (MSC)-derived exosomes.

FOXP3+ regulatory T cells (Tregs) are central to maintaining peripheral tolerance and immune homeostasis. They have the potential to be developed as a cellular therapy to treat various clinical ailments such as autoimmune disorders, inflammatory diseases and to improve transplantation outcomes. However, a major question remains whether Tregs can persist and exert their function effectively in a disease state, where a broad spectrum of inflammatory mediators could inactivate Tregs. In this study, we investigated the potential of mesenchymal stem cell (MSC)-derived exosomes to promote and sustain Tregs function. MSC-conditioned media (MSC-CM) cultured Tregs were more suppressive in both polyclonal and allogeneic responses and were resistant to inflammatory stimulation in vitro compared with the controls. A similar enhancement of Treg function was also observed by culturing Tregs with MSC-derived exosomes alone. The enhanced suppressive activity and stability of Treg cultured in MSC-CM was reduced when exosomes were depleted from MSC-CM. We identified that MSC-derived exosomes could upregulate the expression of LC3(II/I), phosphorylate Jak3 and Stat5 to promote Treg survival, and regulate FOXP3 expression in Tregs. Overall, our study demonstrates that MSC-derived exosomes are capable of enhancing Hucb-Tregs function and stability by activating autophagy and Stat5 signalling pathways. Our findings provide a strong rationale for utilizing MSC-derived exosomes as an effective strategy to enhance Treg function, and improve the overall Tregs-based cell therapy landscape.

Quantitative phosphoproteomics reveals ectopic ATP synthase on mesenchymal stem cells to promote tumor progression via ERK/c-Fos pathway activation.

The tumor microenvironment (TME), which comprises cellular and noncellular components, is involved in the complex process of cancer development. Emerging evidence suggests that mesenchymal stem cells (MSCs), one of the vital regulators of the TME, foster tumor progression through paracrine secretion. However, the comprehensive phosphosignaling pathways that are mediated by MSC-secreting factors have not yet been fully established. In this study, we attempt to dissect the MSC-triggered mechanism in lung cancer using quantitative phosphoproteomics. A total of 1958 phosphorylation sites are identified in lung cancer cells stimulated with MSC-conditioned medium. Integrative analysis of the identified phosphoproteins and predicted kinases demonstrates that MSC-conditioned medium functionally promotes the proliferation and migration of lung cancer via the ERK/phospho-c-Fos-S374 pathway. Recent studies have reported that extracellular ATP accumulates in the TME and stimulates the P2X7R on the cancer cell membrane via purinergic signaling. We observe that ectopic ATP synthase is located on the surface of MSCs and excreted extracellular ATP into the lung cancer microenvironment to trigger the ERK/phospho-c-Fos-S374 pathway, which is consistent with these previous findings. Our results suggest that ectopic ATP synthase on the surface of MSCs releases extracellular ATP into the TME, which promotes cancer progression via activation of the ERK/phospho-c-Fos-S374 pathway.

The Secretome of Preconditioned Mesenchymal Stem Cells Drives Polarization and Reprogramming of M2a Macrophages toward an IL-10-Producing Phenotype.

The preconditioning of mesenchymal stem cells (MSCs) has been recognized as an attractive tool to improve their regenerative and immunomodulatory capacities based on their paracrine effects. In this study, we examined the potential of an MSC-conditioned medium (MSC-CM) to alter the phenotype of murine macrophages and to drive reprogramming toward an anti-inflammatory, M2-like state in vitro. We further explored the impact of MSC cytokine preconditioning on the immunosuppressive properties of the MSC secretome. The MSC-CM suppressed the expression of proinflammatory genes in murine M1 macrophages, but only the CM from preconditioned MSCs (preMSC-CM) downregulated their expression during M1 polarization. Remarkably, only the preMSC-CM significantly increased the expression of M2a-, M2b- and M2c-specific genes and proteins during M2a polarization. Further, macrophages were found to secrete high levels of anti-inflammatory IL-10. Similarly, M2a macrophages cultured in the presence of the preMSC-CM displayed an enhanced expression of M2b/M2c-specific markers, suggesting that the secretome of preMSC promotes the repolarization of M2a-like macrophages to M2b/M2c subtypes. The preMSC-CM was found to be enriched in molecules involved in M2 polarization. Additionally, a unique downregulation of extracellular matrix components was observed. Altogether, the preMSC-CM may provide an attractive strategy to dampen inflammation by suppressing the expression of proinflammatory mediators and promoting the polarization and phenotype switch of M2a cells to IL-10-secreting M2b/M2c-like macrophages.

Mesenchymal Stem Cells and their Derived Exosomes Promote Malignant Phenotype of Polyploid Non-Small-Cell Lung Cancer Cells through AMPK Signaling Pathway.

Chemotherapy is an important method for the treatment of non-small-cell lung cancer (NSCLC), but it can lead to side effects and polyploid cancer cells. The polyploid cancer cells can live and generate daughter cancer cells via budding. Mesenchymal stem cells (MSCs) are pluripotent stem cells with repair and regeneration functions and can resist tissue damage caused by tumor therapy. This study is aimed at investigating the effects of MSCs and their derived exosomes on the biological characteristics of polyploid NSCLC cells and the potential mechanisms. We found that MSC conditioned medium (CM), MSCs, and MSC-exosomes had no effect on cell proliferation of the polyploid A549 and H1299 cells. Compared with the control group, MSCs and MSC-exosomes significantly promoted epithelial mesenchymal transformation, cell migration, antiapoptosis, and autophagy in the polyploid A549 and H1299 by activating AMPK signaling pathway, but no significant changes were observed in MSC-CM treatment. These results revealed that MSCs and MSC-exosomes promoted malignant phenotype of polyploid NSCLC cells through the AMPK signaling pathway.

The effect of mesenchymal stem cell-conditioned medium gel on burn wound healing in rat.

Background and Aim:Stem cells are cells that can proliferate to form a new tissue, leading to its use in regenerative therapy. Stem cells will secrete biological factors, such as growth factors, cytokines, and other proteins to their surroundings and culture medium/conditioned medium (CM), altering tissue physiology. These factors can help wound healing, but their effect on third-degree burns is poorly understood. This research aimed to study the activity of mesenchymal stem cell-conditioned medium gel in healing and repairing third-degree burns on rats skin.Materials and Methods:Twenty-four Sprague–Dawley rats with burn wounds on the dorsal area were divided into four groups; the first group was treated with CM gel, with a concentration equivalent to 0.05% protein, the second group was treated with a placebo gel, the third group with silver sulfadiazine (SSD) cream (SSD-Burnazin contain 10 mg/g SSD), and the fourth group was not given any treatment, for 21 days, and on the final day, the rats were sacrificed, and the skins were taken. All topical treatments completely cover the wound area.Results:Wound healing process indicators observed include wound diameter, scabs’ formation, blister formation, and hair growth every day. The skins taken were processed with hematoxylin-eosin and Masson’s trichrome staining. The indicators studied include neutrophil infiltration, mononuclear cell infiltration, neovascularization, collagen area, and re-epithelization ratio.Conclusion:CM shows better wound healing than other groups and faster hair growth.

Apoptotic effects of human amniotic fluid mesenchymal stem cells conditioned medium on human MCF-7 breast cancer cell line.

Breast cancer, as the most common malignancy among women, is shown to have a high mortality rate and resistance to chemotherapy. Research has shown the possible inhibitory role of Mesenchymal stem cells in curing cancer. Thus, the present work used human amniotic fluid mesenchymal stem cell-conditioned medium (hAFMSCs-CM) as an apoptotic reagent on the human MCF-7 breast cancer cell line. Conditioned medium (CM) was prepared from hAFMSCs. After treating MCF-7 cells with CM, a number of analytical procedures (MTT, real-time PCR, western blot, and flow cytometry) were recruited to evaluate the cell viability, Bax and Bcl-2 gene expression, P53 protein expression, and apoptosis, respectively. Human fibroblast cells (Hu02) were used as the negative control. In addition, an integrated approach to meta-analysis was performed. The MCF-7 cells' viability was decreased significantly after 24 hours (P < 0.0001) and 72 hours (P < 0.05) of treatment. Compared with the control cells, Bax gene's mRNA expression increased and Bcl-2's mRNA expression decreased considerably after treating for 24 hours with 80% hAFMSCs-CM (P = 0.0012, P < 0.0001, respectively); an increasing pattern in P53 protein expression could also be observed. The flow cytometry analysis indicated apoptosis. Results from literature mining and the integrated meta-analysis showed that hAFMSCs-CM is able to activate a molecular network where Bcl2 downregulation stands in harmony with the upregulation of P53, EIF5A, DDB2, and Bax, leading to the activation of apoptosis. Our finding demonstrated that hAFMSCs-CM presents apoptotic effect on MCF-7 cells; therefore, the application of hAFMSCs-CM, as a therapeutic reagent, can suppress breast cancer cells' viabilities and induce apoptosis.

Effects of Cream Containing Three-Dimensional Human Adipose-Derived Mesenchymal Stem Cell Conditioned Medium Secreting Growth Factors on Skin Elasticity

Purpose: In this study, the effect on skin elasticity of a cream containing three-dimensional human adipose tissue derived mesenchymal stem cell conditioned medium (3D ADMSC-CM) was examined.Methods: The clinical efficacy of the cream was evaluated by examining the skin for skin lifting, elasticity, and resilience after examining the cell proliferative capacity, expression levels of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) in 3D ADMSC-CM, and collagen expression in skin cells due to the 3D ADMSC-CM cream.Results: Skin cell viability was well maintained, with no cytotoxicity from the 3D ADMSC-CM. The amount of EGF and VEGF contained in the 3D ADMSC-CM was 2.692 pg/mL and 27.89 pg/mL, respectively. In addition, skin cells treated with the 3D ADMSC-CM cream experienced a collagen expression increase of 183%. In clinical evaluation of the 3D ADMSC-CM cream, skin lifting and skin elasticity improvement showed significant effects at both two and four weeks. After the 3D ADMSC-CM cream was used, the improved skin elasticity and resilience was analyzed by variables, and an improvement was observed in both after two and four weeks of use.Conclusion: A cream containing 3D ADMSC-CM derived from a 3D culture environment, similar to that of an in vivo environment, is highly effective in enhancing skin elasticity, and 3D ADMSC-CM is expected to lead the field of cosmeceuticals.

Anti-inflammatory effects of mesenchymal stem cell-conditioned media inhibited macrophages activation in vitro

The immunomodulatory effects of mesenchymal stem cells (MSCs) on macrophages have been reported, however, the underlying mechanism remains unknown. Therefore, this study aimed to investigate the anti-inflammatory effects of MSCs on lipopolysaccharide (LPS)-stimulated macrophages and the subsequent downregulation of their inflammatory mediators. Macrophages were treated with conditioned media from MSCs, without a subsequent change of MSCs responding to the inflammation state. This study also evaluated whether the interleukin (IL) 4 stimulation of MSCs can improve their anti-inflammatory effects. Results demonstrated that the MSC-conditioned medium (MSC-CM) stimulated with IL4 significantly inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression of LPS-activated macrophages. MSC-CM treatment inhibited the mRNA transcription of the cytokines IL1β and IL6, the chemokines C–C motif ligand (CCL) 2, CCL3, CCL4, and CCL5, and the chemokine receptors CCR2 and CCR5, in LPS-stimulated macrophages. As revealed through western blot and immunofluorescence analyses, the phosphorylation of p38, JNK, and ERK MAPKs, as well as phosphorylation of NF-κB in stimulated macrophages, were also inhibited by the MSC-CM. Further, more potent anti-inflammatory effects were observed with the IL4-stimulated cells, compared with those observed with the non-stimulated cells. The MSC-CM demonstrated a potent anti-inflammatory effect on LPS-activated macrophages, while the IL4 stimulation improved this effect. These findings indicate that MSCs could exert anti-inflammatory effects on macrophages, and may be considered as a therapeutic agent in inflammation treatment.

Investigating the Immunomodulatory Potential of Dental Pulp Stem Cell Cultured on Decellularized Bladder Hydrogel towards Macrophage Response In Vitro.

Mesenchymal stem cells (MSCs) possess immunomodulatory properties and capacity for endogenous regeneration. Therefore, MSC therapy is a promising treatment strategy for COVID-19. However, the cells cannot stay in the lung long enough to exert their function. The extracellular matrix from porcine bladders (B-ECM) has been shown not only to regulate cellular activities but also to possess immunoregulatory characteristics. Therefore, it can be hypothesized that B-ECM hydrogel could be an excellent scaffold for MSCs to grow and could anchor MSCs long enough in the lung so that they can exhibit their immunomodulatory functions. In this study, ECM degradation products and a co-culture system of MSCs and macrophages were developed to study the immunomodulatory properties of ECM and MSCs under septic conditions. The results showed that B-ECM degradation products could decrease pro-inflammatory and increase anti-inflammatory cytokines from macrophages. In an in vivo mimicking co-culture system, MSCs cultured on B-ECM hydrogel exhibited immunomodulatory properties at both gene and protein levels. Both B-ECM degradation products and MSC conditioned medium supported the wound healing of alveolar epithelial cells. The results from the study could offer a basis for investigation of immunomodulation by ECM and MSCs before conducting in vivo experiments, which could later be applied in regenerative medicine.

Ghrelin pretreatment enhanced the protective effect of bone marrow-derived mesenchymal stem cell-conditioned medium on lipopolysaccharide-induced endothelial cell injury

BackgroundLung endothelial barrier injury plays a crucial role in the pathophysiology of acute respiratory distress syndrome. It has been demonstrated that bone marrow-derived mesenchymal stem cells-conditioned medium (BMSCs-CM) and ghrelin have a protective effect. This study investigated if ghrelin pretreatment enhanced the protective effect of BMSCs-CM on lipopolysaccharide (LPS)-induced endothelial cell injury. MethodsBMSCs were isolated from rat bone marrow, expanded, then phenotypically tested for mesenchymal stem cell-identifying criteria by flow cytometry. The effects of the conditioned medium derived from ghrelin-pretreated BMSCs (BMSCs-ghrelin-pretreated-CM) on LPS-injured endothelial cells were evaluated by migration, apoptosis, permeability, and pro-inflammatory factor (e.g., tumor necrosis factor-α, interleukin (IL)-1β, and IL-6) assays in endothelial cells. Further, AKT/GSK3β pathway activation in endothelial cells was examined by Western blot, and the gene expression profiles of ghrelin-pretreated BMSCs were examined by RNA sequencing. ResultsBMSCs-ghrelin-pretreated-CM had a greater protective effect on LPS-induced endothelial cell injury than BMSCs-CM by improving cell migration, alleviating apoptosis, and reducing endothelial permeability and the release of pro-inflammatory factors in endothelial cells. The mechanism is partly related to AKT/GSK3β pathway activation after BMSCs-ghrelin-pretreated-CM treatment. There were five upregulated candidate genes (Wnt5a [i.e., Wnt Family Member 5A], S100b [i.e., S100 Calcium-Binding Protein B], Bmp2 [i.e., Bone Morphogenetic Protein 2], Id4 [i.e., Inhibitor Of DNA Binding 4], and PTHLH [i.e., Parathyroid Hormone Like Hormone]) in BMSCs after ghrelin treatment, and all were associated with AKT pathway activation and endothelial function. ConclusionsGhrelin pretreatment enhanced the protective effect of BMSCs-CM on LPS-induced endothelial cell injury, partly by activating the AKT/GSK3β pathway.

Effect of human adipose-derived mesenchymal stem cell conditioned medium on musculoskeletal pain.

Several studies in animal models have shown the safety and effectiveness of mesenchymal stem cell conditioned medium (MSC-CM) in inflammatory lesions involving muscles and joints. In this report, we retrospectively evaluated 16 patients who received local administration of the human adipose-derived mesenchymal stem cells conditioned medium (hAMSC-CM) for musculoskeletal chronic pain. Overall, 27 body locations expressing pain have been treated. The local administrated dose was 5 ml in the joint cavity and/or 2 ml in the other locations. The patients were asked to conduct self-evaluation of the degree of pain using a numeric rating scale (NRS) questionnaire and record the severity of pain before administration and at 15 min, 1 day, 1 week, and 4 weeks after administration. A second administration has been performed in 7 locations. The analysis was done considering two conditions: the "current pain status" and the "worst pain status in a week." The results showed statistically significant differences between before and after administration at each time point for "current pain status" and at 1-week and 4-week time points for "worst pain status in a week" after first administration (Tukey-Kramer test). After second administration, significant differences were found at 1-week and 4-week time points for "current pain status". No seriousadverse effect was found. It was concluded that local administration of hAMSC-CM appears to be safe and could be expected to have effective therapeutic value against musculoskeletal chronic pain. Further studies are needed to clarify analgesic effects of hAMSC-CM and its underlying mechanism(s).

Intra-tracheal delivery of mesenchymal stem cell-conditioned medium ameliorates pathological changes by inhibiting apoptosis in asthmatic rats.

Asthma, an inflammatory illness of the lungs, remains the most common long-term disease amongst children. This study tried to elaborate the status of apoptosis in asthmatic pulmonary niche after the application of rat mesenchymal stem cells (MSC-CM)-derived secretome. Here, we randomly allocated male Wistar rats into three groups (n = 8); Control animals were intratracheally given 50μl vehicle. In control-matched sensitized rats, 50μl normal saline was used. In the last group, 50μl MSC-CM was applied. Two-week post-administration, transcription of T-bet, GATA-3, Bax, Bcl-2 and Caspase-3 was measured by gene expression analysis. Pathological injuries were monitored using H&E staining. The BALF level of TNF-α was measured using ELISA assay. In asthmatic rats received MSC-CM, the expression of T-bet was increased while the level of GATA-3 decreased compared to the S group (p < 0.05). Levels of BALF TNF-α were suppressed in asthmatic niche after MSC-CM administration (p < 0.05). Compared to the asthmatic group, MSC-CM had potential to alter the expression of apoptosis-related genes in which the expression of Bax and Caspase 3 was decreased and the expression of pro-survival factor, Bcl-2 increased (p < 0.05). Our data notified the potency of direct administration of MSC-CM in the alleviation of airway inflammation, presumably by down regulating apoptotic death in pulmonary niche.

Extracellular vesicle and soluble fractions of adipose tissue-derived mesenchymal stem cells secretome induce inflammatory cytokines modulation in an in vitro model of discogenic pain

Mesenchymal stem cells (MSCs) secretome or conditioned medium (CM) is a complex cocktail of different molecules, some of which, particularly those contained in extracellular vesicles, already have proven therapeutic applications. CM may well represent promising therapy for discogenic pain and the intention of this work is to assess its therapeutic potential using an in vitro model of this condition. This is an experimental study. Our in vitro model comprised nucleus pulposus (NP) and annulus fibrosus (AF) cells inflamed with TNF. To assess the potential therapeutic value of CM and its components, extracellular vesicles (EVs) and soluble culture fraction (SF), cell inflammation took place under 3 different conditions: either in the presence of whole CM, isolated EVs or SF, and concentrations of pro-inflammatory cytokines, metalloproteinases (MMPs) and neurotrophic factors produced in all 3 cases were compared. In the presence of whole CM, both in vitro gene expression by the NP and AF test cells and analysis of their protein content showed high modulatory effects on inflammation and MMP inhibition. The presence of EVs and SF showed similar but much smaller effects, and this was particularly marked in the case of NP cells. Our results show that, compared to EVs and SF, the presence of whole CM has the greatest positive effect on the modulation of pro-inflammatory and catabolic factors. These observations suggest that CM could protect against inflammation and the resulting intervertebral disc (IVD) degeneration that leads to discogenic pain. Many patients' expectations are not met by current non-operative and surgical treatments for discogenic low back pain. We propose the use of the MSCs secretome for assessing its potential as cell-free therapy to treat degenerative disc disease modulating the inflammatory response.

Topical gel of mesenchymal stem cells-conditioned medium under TNF-α precondition accelerates wound closure healing in full-thickness skin defect animal model.

Mesenchymal Stem Cells (MSCs) under TNF-α stimulation (MSC-CM-T) can release numerous trophic and survival molecules that have a promising prospect in wound healing acceleration. However, the effective levels of MSC-CM-T in topical gel preparation to accelerate wound healing should be further explored. The aim of this study was to investigate the effects of MSC-CM-T in topical gel preparation in accelerating optimal wound healing through analyzing PDGF levels, wound closure rate percentages, and fibroblast density appearances. Twenty-four male Wistar rats were performed a full-thickness excision. The group studies were randomly assigned into four subgroups: control gel, control medium, and two treatment groups: MSC-CM-T topical gel at doses of 100 μL and 200 μL (T1 and T2, respectively). Wound closure rates were measured by standard caliper, platelet-derived growth factor (PDGF) levels were analyzed using ELISA on days 3 and 6, whereas the fibroblast density appearances were determined using hematoxylin-eosin staining. This study found a significant increase in PDGF levels in all treatment groups on days 3 and 6. These findings were in line with the increase of wound closure rates in all treatment groups on day 6, in which the high dose of MSC-CM-T was more effective in initiating the increase of wound closure rate. We also found the fibroblast density appearances on day 6 in the T2 group. We conclude that the topical gel of MSC-CM-T is more effective in accelerating wound closure healing through increasing PDGF levels and wound closure percentages and fibroblast density appearances in the skin defect animal models.