Distinct effects of intravenous bone marrow-derived mesenchymal stem cell therapy on ischemic and non-ischemic lungs after ischemia-reperfusion injury.

BACKGROUND: The preclinical efficacy of mesenchymal stem cell (MSC) therapy after intravenous infusion has been promising, but clinical studies have yielded only modest results. Although most preclinical studies have focused solely on the ischemic lung, it is crucial to evaluate both lungs after ischemia-reperfusion injury, considering the various mechanisms involved. This study aimed to bridge this gap by assessing the acute effects of bone marrow MSC(BM) infusion before ischemic insult and evaluating both ischemic and non-ischemic lungs after reperfusion. METHODS: Eighteen male Wistar rats (403 ± 23 g) were anesthetized and mechanically ventilated using a protective strategy. After baseline data collection, the animals were randomized to 3 groups (n = 6/group): (1) SHAM; (2) ischemia-reperfusion (IR), and (3) intravenous MSC(BM) infusion followed by IR. Ischemia was induced by complete clamping of the left hilum, followed by 1 h of reperfusion after clamp removal. At the end of the experiment, the right and left lungs (non-ischemic and ischemic, respectively) were collected for immunohistochemistry and molecular biology analysis. RESULTS: MSC(BM)s reduced endothelial cell damage and apoptosis markers and improved markers associated with endothelial cell integrity in both lungs. In addition, gene expression of catalase and nuclear factor erythroid 2-related factor 2 increased after MSC(BM) therapy. In the ischemic lung, MSC(BM) therapy mitigated endothelial cell damage and apoptosis and increased gene expression associated with endothelial cell integrity. Conversely, in the non-ischemic lung, apoptosis gene expression increased in the IR group but not after MSC(BM) therapy. CONCLUSION: This study demonstrates distinct effects of MSC(BM) therapy on ischemic and non-ischemic lungs after ischemia-reperfusion injury. The findings underscore the importance of evaluating both lung types in ischemia-reperfusion studies, offering insights into the therapeutic potential of MSC(BM) therapy in the context of lung injury.

Potential use of stem cell therapies for treating osteoarthritis and rheumatoid arthritis.

Arthritis, defined as a chronic inflammation often accompanied by swelling of one or more joints, encompasses more than 100 conditions that affect the joints, tissues around them as well as other connective tissues. This condition causes severe discomfort compromising the quality of life drastically, and thereby inflicts severe financial and social impact on the people affected. The incidence rate of arthritis is increasing all around the globe including the United States every year. In general, osteoarthritis (OA) affects more people in comparison to rheumatoid arthritis (RA). In the USA itself, more than 14 million people are affected by OA in comparison to 1.4 million people suffering from RA. In both conditions, elevated levels of proinflammatory cytokines have been recorded, this incidence generally precedes the cartilage degradation observed in the patients. The use of mesenchymal stem cells (MSCs) has proven to be a safe and efficient therapeutic option for treating many inflammation-rooted pathological conditions. Evidence suggests that MSCs down-regulate the effects of proinflammatory cytokines including tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-1B, IL-2, and IL-17, and help restore the functions of immune cells. In addition, these cells promote the polarization of M2 phenotype macrophages, thus contributing to the suppression of the inflammatory process and consequentially to cartilage regeneration. Preclinical and clinical trials have proven the safety and effectiveness of this therapy, supported by the fact that these do not provoke any host immune response, and their influence on the cytokine profiles. An attempt to survey the results of stem cell therapy for treating arthritis has been carried out in this review.

Extracellular vesicles secreted by equine adipose mesenchymal stem cells preconditioned with transforming growth factor ß-1 are enriched in anti-fibrotic miRNAs and inhibit the expression of fibrotic genes in an in vitro system of endometrial stromal cells fibrosis.

Mare endometrosis is a major reproductive problem associated with low fertility and is characterized by persistent inflammation, TGFß-1 signaling, and consequently, extracellular matrix deposition, which compromises endometrial glands. Mesenchymal stem cell-based products (MSCs), such as extracellular vesicles (EVs), have gained attention due to the regulatory effects exerted by their miRNA cargo. Here, we evaluated the impact of preconditioning equine adipose mesenchymal stem cells with TGFß-1 for short or long periods on the anti-fibrotic properties of secreted extracellular vesicles. MSCs were isolated from six healthy horses and exposed to TGFß-1 for 4, 24, and 0 h. The expression of anti-fibrotic and pro-fibrotic miRNAs and mRNAs in treated cells and miRNAs in the cargo of secreted extracellular vesicles was measured. The resulting EVs were added for 48 h to endometrial stromal cells previously induced to a fibrotic status. The expression of anti-fibrotic and pro-fibrotic genes and miRNAs was evaluated in said cells using qPCR and next-generation sequencing. Preconditioning MSCs with TGFß-1 for 4 h enriched the anti-fibrotic miRNAs (mir29c, mir145, and mir200) in cells and EVs. Conversely, preconditioning the cells for 24 h leads to a pro-fibrotic phenotype overexpressing mir192 and mir433. This finding might have implications for developing an EV-based protocol to treat endometrial fibrosis in mares.

Photobiomodulation with laser and led on mesenchymal stem cells viability and wound closure in vitro.

Mesenchymal stem cells can differentiate into specific cell lineages in the tissue repair process. Photobiomodulation with laser and LED is used to treat several comorbidities, can interfere in cell proliferation and viability, in addition to promoting responses related to the physical parameters adopted. Evaluate and compare the effects of laser and LED on mesenchymal cells, with different energy doses and different wavelengths, in addition to viability and wound closure. Mesenchymal stem cells derived from human adipocytes were irradiated with laser (energy of 0.5 J, 2 J and 4 J, wavelength of 660 nm and 830 nm), and LED (energy of 0.5 J, 2 J and 4 J, where lengths are 630 nm and 850 nm). The wound closure process was evaluated through monitoring the reduction of the lesion area in vitro. Viability was determined by analysis with Hoechst and Propidium Iodide markers, and quantification of viable and non-viable cells respectively Data distributions were analyzed using the Shapiro-Wilk test. Homogeneity was analyzed using Levene's test. The comparison between the parameters used was analyzed using the Two-way ANOVA test. The T test was applied to data relating to viability and lesion area. For LED photobiomodulation, only the 630 nm wavelength obtained a significant result in 24, 48 and 72 h (p = 0,027; p = 0,024; p = 0,009). The results related to the in vitro wound closure test indicate that both photobiomodulation with laser and LED demonstrated significant results considering the time it takes to approach the edges (p < 0.05). Considering the in vitro experimental conditions of the study, it is possible to conclude that the physical parameters of photobiomodulation, such as energy and wavelength, with laser or LED in mesenchymal stem cells, can play a potential role in cell viability and wound closure.

Cellular Therapy in Experimental Autoimmune Encephalomyelitis as an Adjuvant Treatment to Translate for Multiple Sclerosis.

This study aims to evaluate and compare cellular therapy with human Wharton's jelly (WJ) mesenchymal stem cells (MSCs) and neural precursors (NPs) in experimental autoimmune encephalomyelitis (EAE), a preclinical model of Multiple Sclerosis. MSCs were isolated from WJ by an explant technique, differentiated to NPs, and characterized by cytometry and immunocytochemistry analysis after ethical approval. Forty-eight rats were EAE-induced by myelin basic protein and Freund's complete adjuvant. Forty-eight hours later, the animals received intraperitoneal injections of 250 ng/dose of Bordetella pertussis toxin. Fourteen days later, the animals were divided into the following groups: a. non-induced, induced: b. Sham, c. WJ-MSCs, d. NPs, and e. WJ-MSCs plus NPs. 1 × 105. Moreover, the cells were placed in a 10 µL solution and injected via a stereotaxic intracerebral ventricular injection. After ten days, the histopathological analysis for H&E, Luxol, interleukins, and CD4/CD8 was carried out. Statistical analyses demonstrated a higher frequency of clinical manifestation in the Sham group (15.66%) than in the other groups; less demyelination was seen in the treated groups than the Sham group (WJ-MSCs, p = 0.016; NPs, p = 0.010; WJ-MSCs + NPs, p = 0.000), and a lower cellular death rate was seen in the treated groups compared with the Sham group. A CD4/CD8 ratio of <1 showed no association with microglial activation (p = 0.366), astrocytes (p = 0.247), and cell death (p = 0.577) in WJ-MSCs. WJ-MSCs and NPs were immunomodulatory and neuroprotective in cellular therapy, which would be translated as an adjunct in demyelinating diseases.

The impact of interleukin-6 (IL-6) and mesenchymal stem cell-derived IL-6 on neurological conditions.

Interleukin-6 (IL-6) is a versatile cytokine crucial for immune response modulation, inflammation regulation, and various physiological processes in the body. Its wide-ranging functions underscore its importance in maintaining health. Dysregulated IL-6 is closely associated with many diseases, making it a key research and therapeutic target. Elevated IL-6 levels in the central nervous system worsen neuroinflammation in neurodegenerative diseases by activating microglia and astrocytes and releasing pro-inflammatory cytokines and neurotoxic molecules. Moreover, dysregulated IL-6 weakens the blood-brain barrier, exacerbating neuroinflammation and neuronal damage by allowing peripheral immune cells and inflammatory mediators to enter the brain. Mesenchymal stem cells (MSCs) show promise in modulating neuroinflammation by regulating IL-6 levels. They effectively suppress pro-inflammatory cytokines, including IL-6, while promoting anti-inflammatory factors. This therapeutic approach highlights the importance of targeting IL-6 and other inflammatory mediators to alleviate neuroinflammation and its adverse effects on neurological disorders. This review provides a comprehensive overview of IL-6's involvement in neurological disorders, examining endogenous IL-6 and IL-6 derived from MSCs. We explore IL-6's mechanisms affecting neuronal function, survival, and immune modulation in the central nervous system. Additionally, we discuss the potential of MSC-derived IL-6 in neuroregeneration and neuroprotection. By elucidating IL-6's interplay with neurological pathologies, this review offers insights into novel therapeutic strategies targeting IL-6 signaling pathways for neurological disorders.

microRNA-181a-5p promotes fibroblast differentiation of mesenchymal stem cells in rats with pelvic floor dysfunction.

The use of stem cells capable of multilineage differentiation in treating Pelvic Floor Dysfunction (PFD) holds great promise since they are susceptible to entering connective tissue of various cell types and repairing damaged tissues. This research investigated the effect of microRNA-181a-5p (miR-181a-5p) on Bone Marrow Mesenchymal Stem Cells (BMSCs) in rats with PFD. BMSCs were transfected and analyzed for their fibroblast differentiation ability. miR-181a-5p, MFN1, and fibroblast-related genes were quantitatively analyzed. Whether MFN1 is a target gene of miR-181a-5p was predicted and confirmed. The efficacy of BMSCs in vivo rats with PFD was evaluated by measuring Leak Point Pressure (LPP), Conscious Cystometry (CMG), hematoxylin and eosin staining, and Masson staining. The present results discovered that miR-181a-5p was up-regulated and MFN1 was down-regulated during the differentiation of BMSCs into fibroblasts. Fibroblast differentiation of BMSCs was promoted after miR-181a-5p was induced or MFN1 was suppressed, but it was suppressed after miR-181a-5p was silenced. miR-181a-5p improved LPP and conscious CMG outcomes in PDF rats by targeting MFN1 expression, thereby accelerating fibroblast differentiation of BMSCs. In brief, miR-181a-5p induces fibroblast differentiation of BMSCs in PDF rats by MFN1, potentially targeting PDF therapeutics.

How long does the biological effect of a red light-emitting diode last on adipose-derived mesenchymal stem cells?

This research investigated the duration of the influence of red light-emitting diodes (LED, 630 nm; output power: 2452.5 mW; laser beam: 163.5 cm2; irradiance: 15 mW/cm2; radiant exposure: 4 J/cm2) on different periods after irradiation (6, 12, 24, 48, and 72 h) on adipose-derived mesenchymal stem cells' (AdMSCs) metabolism and paracrine factors. AdMSCs were irradiated three times every 48 h. Twenty-four hours after the last irradiation, there was a higher MTT absorbance, followed by a decrease after 48 h. The cells' secretome showed increased levels of IL-6 and VEGF after 12 and 24 h, but this was reversed after 48 h. Additionally, LED irradiation resulted in higher levels of nitrite and did not affect oxidative stress markers. LED irradiation had significant effects on AdMSCs after 24 h compared to other groups and its control group.

The autophagy protein RUBCNL/PACER represses RIPK1 kinase-dependent apoptosis and necroptosis.

Mesenchymal stem cells (MSCs) are used in cell therapy; nonetheless, their application is limited by their poor survival after transplantation in a proinflammatory microenvironment. Macroautophagy/autophagy activation in MSCs constitutes a stress adaptation pathway, promoting cellular homeostasis. Our proteomics data indicate that RUBCNL/PACER (RUN and cysteine rich domain containing beclin 1 interacting protein like), a positive regulator of autophagy, is also involved in cell death. Hence, we screened MSC survival upon various cell death stimuli under loss or gain of function of RUBCNL. MSCs were protected from TNF (tumor necrosis factor)-induced regulated cell death when RUBCNL was expressed. TNF promotes inflammation by inducing RIPK1 kinase-dependent apoptosis or necroptosis. We determine that MSCs succumb to RIPK1 kinase-dependent apoptosis upon TNF sensing and necroptosis when caspases are inactivated. We show that RUBCNL is a negative regulator of both RIPK1-dependent apoptosis and necroptosis. Furthermore, RUBCNL mutants that lose the ability to regulate autophagy, retain their function in negatively regulating cell death. We also found that RUBCNL forms a complex with RIPK1, which disassembles in response to TNF. In line with this finding, RUBCNL expression limits assembly of RIPK1-TNFRSF1A/TNFR1 complex I, suggesting that complex formation between RUBCNL and RIPK1 represses TNF signaling. These results provide new insights into the crosstalk between the RIPK1-mediated cell death and autophagy machineries and suggest that RUBCNL, due to its functional duality in autophagy and apoptosis/necroptosis, could be targeted to improve the therapeutic efficacy of MSCs. Abbreviations: BAF: bafilomycin A1; CASP3: caspase 3; Caspases: cysteine-aspartic proteases; cCASP3: cleaved CASP3; CQ: chloroquine; CHX: cycloheximide; cPARP: cleaved poly (ADP-ribose) polymerase; DEPs: differential expressed proteins; ETO: etoposide; MEF: mouse embryonic fibroblast; MLKL: mixed lineage kinase domain-like; MSC: mesenchymal stem cell; MTORC1: mechanistic target of rapamycin kinase complex 1; Nec1s: necrostatin 1s; NFKB/NF-kB: nuclear factor of kappa light polypeptide gene enhancer in B cells; PLA: proximity ligation assay; RCD: regulated cell death; RIPK1: receptor (TNFRSF)-interacting serine-threonine kinase 1; RIPK3: receptor-interacting serine-threonine kinase 3; RUBCNL/PACER: RUN and cysteine rich domain containing beclin 1 interacting protein like; siCtrl: small interfering RNA nonsense; siRNA: small interfering RNA; TdT: terminal deoxynucleotidyl transferase; Tm: tunicamycin; TNF: tumor necrosis factor; TNFRSF1A/TNFR1: tumor necrosis factor receptor superfamily, member 1a.

A Minimally Invasive Surgical Procedure to Harvest Palate Periosteum as a Source of Mesenchymal Stromal/Stem Cells for Bone Tissue Engineering.

The aim of this study is to validate a minimally invasive surgical procedure to harvest palate periosteum as a source of tissue for mesenchymal stromal/stem cells. We performed a standardized procedure to harvest the palate periosteum in ten subjects, which consisted of a 3 mm disposable punch and a Molt periosteal elevator to harvest a small full-thickness fragment of soft tissue at the hard palate area, between the upper bicuspids, 3 to 4 mm apical to the cement enamel junction. The one-third inner portion was fragmented, and following standard cell culture procedures, the adherent cells were cultured for three passages, after obtaining 70-90% confluence. Cell morphology analysis, flow cytometry analysis, and viability and osteogenic differentiation assays were performed. In all 10 cases, uneventful healing was observed, with no need for analgesic intake. The evaluation of cell morphology showed elongated spindle-shaped cells distributed in woven patterns. A high viability range was verified as well as an immunophenotype compatible with mesenchymal stem cell lineage. The differentiation assay showed the potential of the cells to differentiate into the osteogenic lineage. These results demonstrate that the minimally invasive proposed surgical technique is capable of supplying enough periosteum source tissue for stem cell culture and bone tissue engineering.

Mesenchymal stem cells in animal reproduction: sources, uses and scenario.

Studies regarding mesenchymal stem cells turned up in the 1960's and this cell type created a great number of questions about its functions and applicability in science and medicine. When used with therapeutic intent, these cells present an inclination to migrate to sites of injury, inflammation or disease, where they secrete bioactive factors that stimulates the synthesis of new tissue. In this context, studies using rodents reported that MSCs promoted positive effects in the ovarian function in mice with premature aging of follicular reserve. In female bovines, experimental stem cell-based therapies have been used to either generate new oocytes with in vitro quality or stimulate such action in vivo. It is also reported, that the intraovarian application of mesenchymal stem cells generates a greater production of embryos in vitro and the production of early and expanded blastocysts. Additionally, analysis of ovarian tissue in animal subjected to treatment showed an increase in the number of developing follicles. Nevertheless, the treatments involving stem cells with different modes of application, different sources and different species were able to act on the hormonal, tissue, cellular and metabolic levels, generating positive results in the recovery and improvement of ovarian functions.

Estudos sobre células-tronco mesenquimais surgiram na década de 1960 e esse tipo de célula gerou muitas dúvidas sobre suas funções e aplicabilidade na ciência e na medicina. Quando utilizadas com intuito terapêutico, essas células apresentam tendência a migrar para locais de lesão, inflamação ou doença, onde secretam fatores bioativos que estimulam a síntese de novos tecidos. Nesse contexto, estudos utilizando roedores relataram que as CTM promoveram efeitos positivos na função ovariana em camundongos com envelhecimento precoce da reserva folicular. Em fêmeas bovinas, terapias experimentais baseadas em células-tronco têm sido utilizadas para gerar novos oócitos com qualidade in vitro ou estimular tal ação in vivo. É relatado também que a aplicação intraovariana de células-tronco mesenquimais gera maior produção de embriões in vitro e produção de blastocistos precoces e expandidos. Além disso, a análise do tecido ovariano em animais submetidos ao tratamento mostrou aumento no número de folículos em desenvolvimento. Apesar disso, os tratamentos envolvendo células-tronco com diferentes modos de aplicação, diferentes fontes e diferentes espécies foram capazes de atuar nos níveis hormonal, tecidual, celular e metabólico, gerando resultados positivos na recuperação e melhora das funções ovarianas.

The effect of diabetes mellitus on differentiation of mesenchymal stem cells into insulin-producing cells.

BACKGROUND: Diabetes mellitus (DM) is a global epidemic with increasing incidences. DM is a metabolic disease associated with chronic hyperglycemia. Aside from conventional treatments, there is no clinically approved cure for DM up till now. Differentiating mesenchymal stem cells (MSCs) into insulin-producing cells (IPCs) is a promising approach for curing DM. Our study was conducted to investigate the effect of DM on MSCs differentiation into IPCs in vivo and in vitro. METHODS: We isolated adipose-derived mesenchymal stem cells (Ad-MSCs) from the epididymal fat of normal and STZ-induced diabetic Sprague-Dawley male rats. Afterwards, the in vitro differentiation of normal-Ad-MSCs (N-Ad-MSCs) and diabetic-Ad-MSCs (DM-Ad-MSCs) into IPCs was compared morphologically then through determining the gene expression of ß-cell markers including neurogenin-3 (Ngn-3), homeobox protein (Nkx6.1), musculoaponeurotic fibrosarcoma oncogene homolog A (MafA), and insulin-1 (Ins-1) and eventually, through performing glucose-stimulated insulin secretion test (GSIS). Finally, the therapeutic potential of N-Ad-MSCs and DM-Ad-MSCs transplantation was compared in vivo in STZ-induced diabetic animals. RESULTS: Our results showed no significant difference in the characteristics of N-Ad-MSCs and DM-Ad-MSCs. However, we demonstrated a significant difference in their abilities to differentiate into IPCs in vitro morphologically in addition to ß-cell markers expression, and functional assessment via GSIS test. Furthermore, the abilities of both Ad-MSCs to control hyperglycemia in diabetic rats in vivo was assessed through measuring fasting blood glucose (FBGs), body weight (BW), histopathological examination of both pancreas and liver and immunoexpression of insulin in pancreata of study groups. CONCLUSION: Our findings reveal the effectiveness of N-Ad-MSCs in differentiating into IPCs in vitro and controlling the hyperglycemia of STZ-induced diabetic rats in vivo compared to DM-Ad-MSCs.

The safety profile of mesenchymal stem cell therapy administered through intrathecal injections for treating neurological disorders: a systematic review and meta-analysis of randomised controlled trials.

BACKGROUND: Based on previous in vivo studies and human trials, intrathecal cell delivery is a safe and relevant therapeutic tool for improving patient's quality of life with neurological conditions. We aimed to characterise the safety profile of intrathecally delivered Mesenchymal stem cells (MSCs). METHODS: Ovid MEDLINE, Embase, Scopus, Cochrane Library, KCI-Korean Journal Database, and Web of Science. Databases were searched from their inception until April 13, 2023. Randomised Controlled Trials (RCTs) that compared intrathecal delivery of MSCs to controls in adult populations were included. Adverse events (AEs) were pooled and meta-analysed using DerSimonian-Laird random effects models with a correction factor 0.5 added to studies with zero count cells. Pooled AEs were described using Risk ratio (RR) and 95% confidence intervals (95% CI). Then, a random-effects meta-regress model on study-level summary data was performed to explore the relationship between the occurrence of AEs and covariates thought to modify the overall effect estimate. Finally, publication bias was assessed. RESULTS: 303 records were reviewed, and nine RCTs met the inclusion criteria and were included in the quantitative synthesis (n = 540 patients). MSCs delivered intrathecally, as compared to controls, were associated with an increased probability of AEs of musculoskeletal and connective tissue disorders (categorised by Common Terminology Criteria for Adverse Events-CTCAE version 5.0) (RR: 1.61, 95% CI 1.19-2.19, I2 = 0%). The random-effects meta-regress model suggested that fresh MSCs increased the probability of occurrence of AEs compared to cryopreserved MSCs (RR: 1.554; p-value = 0.048; 95% CI 1.004-2.404), and the multiple-dose, decreased the probability of AEs by 36% compared to single doses (RR: 0.644; p-value = 0.048; 95% CI 0.416-0.996); however, univariate random effects meta-regression models revealed a not significant association between the occurrence of AEs from MSCs intrathecal delivery and each covariate. CONCLUSIONS: Intrathecal delivery of MSCs was associated with a slight increase in AEs associated with musculoskeletal and connective tissue disorders, albeit without serious AEs. We conclude that intrathecal MSCs delivery is safe for patients with neurological conditions. However, further high-quality, large-scale RCTs are needed to confirm these findings.

Influence of Human Bone Marrow Mesenchymal Stem Cells Secretome from Acute Myeloid Leukemia Patients on the Proliferation and Death of K562 and K562-Lucena Leukemia Cell Lineages.

Leukemias are among the most prevalent types of cancer worldwide. Bone marrow mesenchymal stem cells (MSCs) participate in the development of a suitable niche for hematopoietic stem cells, and are involved in the development of diseases such as leukemias, to a yet unknown extent. Here we described the effect of secretome of bone marrow MSCs obtained from healthy donors and from patients with acute myeloid leukemia (AML) on leukemic cell lineages, sensitive (K562) or resistant (K562-Lucena) to chemotherapy drugs. Cell proliferation, viability and death were evaluated, together with cell cycle, cytokine production and gene expression of ABC transporters and cyclins. The secretome of healthy MSCs decreased proliferation and viability of both K562 and K562-Lucena cells; moreover, an increase in apoptosis and necrosis rates was observed, together with the activation of caspase 3/7, cell cycle arrest in G0/G1 phase and changes in expression of several ABC proteins and cyclins D1 and D2. These effects were not observed using the secretome of MSCs derived from AML patients. In conclusion, the secretome of healthy MSCs have the capacity to inhibit the development of leukemia cells, at least in the studied conditions. However, MSCs from AML patients seem to have lost this capacity, and could therefore contribute to the development of leukemia.

Phenotypic characteristics and differentiation potential of gingival mesenchymal stem cells in hyperglycemia ­ an ex vivo exploratory study / Características fenotípicas y potencial de diferenciación de las células madre mesenquimales gingivales en la hiperglucemia: un estudio exploratorio ex vivo

Background: The therapeutic use of gingival mesenchymal stem cells (GMSCs) as autologous cells may pose the challenge of alterations inflicted by the hyperglycemic environment. Objective: This study aims to assess the effects of hyperglycemia on the characteristics of GMSCs in diabetics. Materials and Methods: 10 patients who consented and fulfilled the criteria for inclusion and exclusion were recruited and categorized as test (HbA1c > 6.5) and control (HbA1c < 6.0). Gingival explants were obtained from gingival collar of teeth, washed, digested and cultured. The cells were subjected to microscopic observation to assess phenotype characteristics, and flow cytometry and qRT-PCR to assess differentiation potential. Stem cell markers CD90, CD73, CD105, CD34, CD45, HLA DR & HLA ABC, osteogenic differentiation markers RUNX2 & OCN, adipogenic differentiation markers PPARG2 & FABP4 and chondrogenic differentiation markers SOX9 & AGCN were evaluated. Results: Microscopic appearance of spindle shaped cells was found to be comparable in both groups. Flow cytometry results demonstrated comparable expressions with both groups, samples being positive for CD90, CD73, CD105, HLA ABC and negative for CD34, CD45 & HLA DR. There were variations in the expression of markers when assessed for differentiation potentials. Conclusions: The hyperglycemic environment did not manifest any changes in the phenotypic characteristics of GMSCs among diabetics. However, the expression of certain differentiation markers was significantly altered in the diabetic test population included. Further research is being conducted to understand the GMSCs in a hyperglycemic environment with an aim to develop strategies to optimize its clinical implications. Keywords: Gingiva; Mesenchymal stem cells; Diabetes mellitus; Cell Differentiation; Hyperglycemia; Flow cytometry.

Antededentes: El uso terapéutico de células madre mesenquimales gingivales(GMSC) como células autólogas puede plantear el desafío de las alteraciones infligidas por el entorno hiperglucémico. Objetivo: Este estudio tiene como objetivo evaluar los efectos de la hiperglucemia sobre las características de las GMSC en diabéticos. Materiales y Métodos: Se reclutaron y categorizaron 10 pacientes que dieron su consentimiento y cumplieron los criterios de inclusión y exclusión como prueba (HbA1c > 6,5) y control (HbA1c < 6,0). Los explantes gingivales se obtuvieron del cuello gingival de los dientes, se lavaron, digirieron y cultivaron. Las células se sometieron a observación microscópica para evaluar las características fenotípicas y a citometría de flujo y qRT-PCR para evaluar el potencial de diferenciación. Se evaluaron los marcadores de células madre CD90, CD73, CD105, CD34, CD45, HLA DR y HLA ABC, marcadores de diferenciación osteogénica RUNX2 y OCN, marcadores de diferenciación adipogénica PPARG2 y FABP4 y marcadores de diferenciación condrogénica SOX9 y AGCN. Resultados: Se encontró que la apariencia microscópica de las células fusiformes era comparable en ambos grupos. Los resultados de la citometría de flujo demostraron expresiones comparables en ambos grupos, siendo las muestras positivas para CD90, CD73, CD105, HLA ABC y negativas para CD34, CD45 y HLA DR. Hubo variaciones en la expresión de los marcadores cuando se evaluaron los potenciales de diferenciación. Conclusiones: El entorno hiperglucémico no manifestó ningún cambio en las características fenotípicas de las GMSC entre los diabéticos. Sin embargo, la expresión de ciertos marcadores de diferenciación se alteró significativamente en la población de prueba de diabetes incluida. Se están realizando más investigaciones para comprender las GMSC en un entorno hiperglucémico con el objetivo de desarrollar estrategias para optimizar sus implicaciones clínicas.

Meniscal repair with additive manufacture of bioresorbable polymer: From physicochemical characterization to implantation of 3D printed poly (L-co-D, L lactide-co-trimethylene carbonate) with autologous stem cells in rabbits.

Three-dimensional (3D) structures are actually the state-of-the-art technique to create porous scaffolds for tissue engineering. Since regeneration in cartilage tissue is limited due to intrinsic cellular properties this study aims to develop and characterize three-dimensional porous scaffolds of poly (L-co-D, L lactide-co-trimethylene carbonate), PLDLA-TMC, obtained by 3D fiber deposition technique. The PLDLA-TMC terpolymer scaffolds (70:30), were obtained and characterized by scanning electron microscopy, gel permeation chromatography, differential scanning calorimetry, thermal gravimetric analysis, compression mechanical testing and study on in vitro degradation, which showed its amorphous characteristics, cylindrical geometry, and interconnected pores. The in vitro degradation study showed significant loss of mechanical properties compatible with a decrease in molar mass, accompanied by changes in morphology. The histocompatibility association of mesenchymal stem cells from rabbit's bone marrow, and PLDLA-TMC scaffolds, were evaluated in the meniscus regeneration, proving the potential of cell culture at in vivo tissue regeneration. Nine New Zealand rabbits underwent total medial meniscectomy, yielding three treatments: implantation of the seeded PLDLA-TMC scaffold, implantation of the unseeded PLDLA-TMC and negative control (defect without any implant). After 24 weeks, the results revealed the presence of fibrocartilage in the animals treated with polymer. However, the regeneration obtained with the seeded PLDLA-TMC scaffolds with mesenchymal stem cells had become intimal to mature fibrocartilaginous tissue of normal meniscus both macroscopically and histologically. This study demonstrated the effectiveness of the PLDLA-TMC scaffold in meniscus regeneration and the potential of mesenchymal stem cells in tissue engineering, without the use of growth factors. It is concluded that bioresorbable polymers represent a promising alternative for tissue regeneration.

The role of mesenchymal stem cells in early programming of adipose tissue in the offspring of women with obesity.

Maternal obesity is a well-known risk factor for developing premature obesity, metabolic syndrome, cardiovascular disease and type 2 diabetes in the progeny. The development of white adipose tissue is a dynamic process that starts during prenatal life: fat depots laid down in utero are associated with the proportion of fat in children later on. How early this programming takes place is still unknown. However, recent evidence shows that mesenchymal stem cells (MSC), the embryonic adipocyte precursor cells, show signatures of the early setting of an adipogenic committed phenotype when exposed to maternal obesity. This review aims to present current findings on the cellular adaptations of MSCs from the offspring of women with obesity and how the metabolic environment of MSCs could affect the early commitment towards adipocytes. In conclusion, maternal obesity can induce early programming of fetal adipose tissue by conditioning MSCs. These cells have higher expression of adipogenic markers, altered insulin signalling and mitochondrial performance, compared to MSCs of neonates from lean pregnancies. Fetal MSCs imprinting by maternal obesity could help explain the increased risk of childhood obesity and development of further noncommunicable diseases.

Mesenchymal stem cells induce an immunosuppressive microenvironment in pituitary tumors.

BACKGROUND: The tumor microenvironment (TME) includes diverse cellular components such as mesenchymal stem cells (MSC) and immune cells among others. MSC have been isolated from different tumors and they favor tumor cell growth, however, their role in pituitary tumors (PT) remains unknown. Herein we report the presence of MSCs in 2 ACTH-secreting PT causing Cushing disease (MCU), 2 nonfunctioning adenomas of gonadotrope differentiation (MNF) and 2 non tumoral pituitary glands (MS). METHODS: We have analyzed their transcriptomic profiles by RNAseq and compared MSC in terms of their immunosuppressive effects against lymphoid T cell and macrophage populations by means of co-cultures and flow cytometry. RESULTS: Our transcriptomic analysis revealed molecular differences between MSC derived from non-tumoral pituitaries and MSC derived from PT. Two distinct subpopulations of MSC, one displaying immunosuppressive properties and the other with increased pro-proliferative capabilities, regardless of their origin. MSC derived from ACTH- and nonfunctioning PT, but not those derived from non-tumoral glands significantly inhibited the proliferation of activated T cells, favored the generation of Tregs and promote M2 macrophage polarization. Such immunosuppressive effects were correlated with an upregulation of programmed death ligand 1 and intracellular expression of macrophage colony stimulating factor (M-CSF) and IL-10. Importantly, MSC derived from ACTH-PT showed a higher immunosuppressive potential than MSC isolated from nonfunctioning tumors. CONCLUSION: This study demonstrates the presence of at least two MSC subpopulations in the pituitary gland and suggests that immunosuppressive effects of MSC may have important implications in PT growth.

Mesenchymal Stem Cell Engagement Modulates Neuroma Microenviroment in Rats and Humans and Prevents Postamputation Pain.

Postamputation pain is currently managed unsatisfactorily with neuron-targeted pharmacological and interventional therapies. Non-neuronal pain mechanisms have emerged as crucial factors in the development and persistence of postamputation pain. Consequently, these mechanisms offer exciting prospects as innovative therapeutic targets. We examined the hypothesis that engaging mesenchymal stem cells (MSCs) would foster local neuroimmune interactions, leading to a potential reduction in postamputation pain. We utilized an ex vivo neuroma model from a phantom limb pain patient to uncover that the oligodeoxynucleotide IMT504 engaged human primary MSCs to promote an anti-inflammatory microenvironment. Reverse translation experiments recapitulated these effects. Thus, in an in vivo rat model, IMT504 exhibited strong efficacy in preventing autotomy (self-mutilation) behaviors. This effect was linked to a substantial accumulation of MSCs in the neuroma and associated dorsal root ganglia and the establishment of an anti-inflammatory phenotype in these compartments. Centrally, this intervention reduced glial reactivity in the dorsal horn spinal cord, demonstrating diminished nociceptive activity. Accordingly, the exogenous systemic administration of MSCs phenocopied the behavioral effects of IMT504. Our findings underscore the mechanistic relevance of MSCs and the translational therapeutic potential of IMT504 to engage non-neuronal cells for the prevention of postamputation pain. PERSPECTIVE: The present study suggests that IMT504-dependent recruitment of endogenous MSCs within severely injured nerves may prevent post-amputation pain by modifying the inflammatory scenario at relevant sites in the pain pathway. Reinforcing data in rat and human tissues supports the potential therapeutic value of IMT504 in patients suffering postamputation pain.

Osteosarcoma cells exhibit functional interactions with stromal cells, fostering a lung microenvironment conducive to the establishment of metastatic tumor cells.

BACKGROUND: Osteosarcoma (OS) stands out as the most common bone tumor, with approximately 20% of the patients receiving a diagnosis of metastatic OS at their initial assessment. A significant challenge lies in the frequent existence of undetected metastases during the initial diagnosis. Mesenchymal stem cells (MSCs) possess unique abilities that facilitate tumor growth, and their interaction with OS cells is crucial for metastatic spread. METHODS AND RESULTS: We demonstrated that, in vitro, MSCs exhibited a heightened migration response toward the secretome of non-metastatic OS cells. When challenged to a secretome derived from lungs preloaded with OS cells, MSCs exhibited greater migration toward lungs colonized with metastatic OS cells. Moreover, in vivo, MSCs displayed preferential migratory and homing behavior toward lungs colonized by metastatic OS cells. Metastatic OS cells, in turn, demonstrated an increased migratory response to the MSCs' secretome. This behavior was associated with heightened cathepsin D (CTSD) expression and the release of active metalloproteinase 2 (MMP2) by metastatic OS cells. CONCLUSIONS: Our assessment focused on two complementary tumor capabilities crucial to metastatic spread, emphasizing the significance of inherent cell features. The findings underscore the pivotal role of signaling integration within the niche, with a complex interplay of migratory responses among established OS cells in the lungs, prometastatic OS cells in the primary tumor, and circulating MSCs. Pulmonary metastases continue to be a significant factor contributing to OS mortality. Understanding these mechanisms and identifying differentially expressed genes is essential for pinpointing markers and targets to manage metastatic spread and improve outcomes for patients with OS.