Criopreservação de células-tronco mesenquimais do tecido adiposo: Uma alternativa para lipoenxertia seriada na reconstrução mamária / Cryopreservation of adipose tissue-derived mesenchymal stem cells: An alternative to serial fat grafting in breast reconstruction

Introdução: A lipoenxertia é um enxerto autólogo de células do tecido celular subcutâneo, que pode ser utilizada como técnica complementar na reconstrução mamária. Diante disso, a criopreservação de células-tronco mesenquimais provenientes de tecido adiposo (CTDAs) poderia ser uma maneira de realizar a coleta em um tempo cirúrgico e após realizar a lipoenxertia de forma fracionada. O dimetilsulfóxido (DMSO) é um criopreservante utilizado em pesquisas com células, porém é potencialmente tóxico, o que impossibilitaria a utilização de CTDAs criopreservadas na prática clínica. Novos criopreservantes celulares, sem toxicidade, vêm sendo descritos na literatura científica experimental, como as substâncias L-prolina e trealose. Com isso, esse trabalho teve como objetivo avaliar a viabilidade de CTDAs criopreservadas com a combinação de L-prolina e trealose, em um período de até 90 dias. Método: Estudo experimental, no qual foram obtidas amostras de lipoaspirado provenientes de 9 pacientes. A fração celular foi processada e congelada com L-prolina (1,5M) + trealose (0,2M), ou com DMSO + soro fetal bovino (SFB), como controle. Após 30 e 90 dias, as amostras foram descongeladas e a viabilidade celular foi avaliada pela técnica de MTT. Resultados: A análise das CTDAs, após 1 e 3 meses de congelamento, indicou que as amostras tratadas com L-prolina + trealose apresentaram viabilidade semelhante àquelas preservadas com DMSO e SFB (p=0,444). Conclusão: A associação de L-prolina e trealose manteve CTDA viáveis por 30 e 90 dias de congelamento, podendo ser uma alternativa como criopreservante celular sem toxicidade e viabilizando o uso de lipoenxertia seriada.

Introduction: Fat grafting is an autologous graft of cells from subcutaneous tissue, which can be used as a complementary technique in breast reconstruction. Given this, the cryopreservation of adipose tissue-derived mesenchymal stem cells (ADMSCs) could be a way to collect them in one surgical procedure and after performing fractional fat grafting. Dimethyl sulfoxide (DMSO) is a cryopreservative used in cell research, but it is potentially toxic, which would make it impossible to use cryopreserved ADMSCs in clinical practice. New cellular cryopreservatives, without toxicity, have been described in the experimental scientific literature, such as the substances L-proline and trehalose. Therefore, this work aimed to evaluate the viability of ADMSCs cryopreserved with the combination of L-proline and trehalose over up to 90 days. Method: Experimental study in which lipoaspirate samples were obtained from 9 patients. The cellular fraction was processed and frozen with L-proline (1.5M) + trehalose (0.2M) or with DMSO + fetal bovine serum (FBS) as control. After 30 and 90 days, the samples were thawed, and cell viability was assessed using the MTT technique. Results: The analysis of ADMSCs, after 1 and 3 months of freezing, indicated that samples treated with L-proline + trehalose showed similar viability to those preserved with DMSO and SFB (p=0.444). Conclusion: The association of L-proline and trehalose kept ADMSC viable for 30 and 90 days of freezing, and could be an alternative as a cellular cryopreservative without toxicity and enabling the use of serial fat grafting.

Resveratrol Alleviates Osteoporosis by Promoting Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells via SITR1/PI3K/AKT Pathway / El Resveratrol Alivia la Osteoporosis al Promover la Diferenciación Osteogénica de las Células Madre Mesenquimales de la Médula Ósea a Través de la Vía SITR1/PI3K/AKT

SUMMARY: Senile osteoporosis is mainly caused by reduced osteoblast differentiation and has become the leading cause of fractures in the elderly worldwide. Natural organics are emerging as a potential option for the prevention and treatment of osteoporosis. This study was designed to study the effect of resveratrol on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in osteoporosis mice. A mouse model of osteoporosis was established by subcutaneous injection of dexamethasone and treated with resveratrol administered by gavage. In vivo and in vitro, we used western blot to detect protein expression, and evaluated osteogenic differentiation of BMSCs by detecting the expression of osteogenic differentiation related proteins, calcium deposition, ALP activity and osteocalcin content. Resveratrol treatment significantly increased the body weight of mice, the level of serum Ca2+, 25(OH)D and osteocalcin, ration of bone weight, bone volume/total volume, trabecular thickness, trabecular number, trabecular spacing and cortical thickness in osteoporosis mice. In BMSCs of osteoporosis mice, resveratrol treatment significantly increased the expression of Runx2, osterix (OSX) and osteocalcin (OCN) protein, the level of calcium deposition, ALP activity and osteocalcin content. In addition, resveratrol treatment also significantly increased the expression of SIRT1, p-PI3K / PI3K and p-AKT / AKT in BMSCs of osteoporosis mice. In vitro, resveratrol increased the expression of SIRT1, p-PI3K / PI3K and p-AKT / AKT, Runx2, OSX and OCN protein, the level of calcium deposition, ALP activity and osteocalcin content in BMSCs in a concentration-dependent manner, while SIRT1 knockdown significantly reversed the effect of resveratrol. Resveratrol can attenuate osteoporosis by promoting osteogenic differentiation of bone marrow mesenchymal stem cells, and the mechanism may be related to the regulation of SIRT1/PI3K/AKT pathway.

La osteoporosis senil es causada principalmente por una diferenciación reducida de osteoblastos y se ha convertido en la principal causa de fracturas en las personas mayores en todo el mundo. Los productos orgánicos naturales están surgiendo como una opción potencial para la prevención y el tratamiento de la osteoporosis. Este estudio fue diseñado para estudiar el efecto del resveratrol en la diferenciación osteogénica de las células madre mesenquimales de la médula ósea (BMSC) en ratones con osteoporosis. Se estableció un modelo de osteoporosis en ratones mediante inyección subcutánea de dexametasona y se trató con resveratrol administrado por sonda. In vivo e in vitro, utilizamos Western blot para detectar la expresión de proteínas y evaluamos la diferenciación osteogénica de BMSC detectando la expresión de proteínas relacionadas con la diferenciación osteogénica, la deposición de calcio, la actividad de ALP y el contenido de osteocalcina. El tratamiento con resveratrol aumentó significativamente el peso corporal de los ratones, el nivel sérico de Ca2+, 25(OH)D y osteocalcina, la proporción de peso óseo, el volumen óseo/ volumen total, el espesor trabecular, el número trabecular, el espaciado trabecular y el espesor cortical en ratones con osteoporosis. En BMSC de ratones con osteoporosis, el tratamiento con resveratrol aumentó significativamente la expresión de las proteínas Runx2, osterix (OSX) y osteocalcina (OCN), el nivel de deposición de calcio, la actividad de ALP y el contenido de osteocalcina. Además, el tratamiento con resveratrol también aumentó significativamente la expresión de SIRT1, p-PI3K/PI3K y p-AKT/AKT en BMSC de ratones con osteoporosis. In vitro, el resveratrol aumentó la expresión de las proteínas SIRT1, p-PI3K/PI3K y p- AKT/AKT, Runx2, OSX y OCN, el nivel de deposición de calcio, la actividad de ALP y el contenido de osteocalcina en BMSC de manera dependiente de la concentración, mientras que La caída de SIRT1 revirtió significativamente el efecto del resveratrol. El resveratrol puede atenuar la osteoporosis al promover la diferenciación osteogénica de las células madre mesenquimales de la médula ósea, y el mecanismo puede estar relacionado con la regulación de la vía SIRT1/PI3K/AKT.

Therapeutic effect of transplantation of bone marrow mesenchymal stem cells co-cultured with bone marrow M2 macrophages on a rat model of liver cirrhosis / 临床肝胆病杂志

ObjectiveTo investigate the effect of transplantation of bone marrow mesenchymal stem cells （BMSCs） co-cultured with bone marrow-derived M2 macrophages （M2-BMDMs）， named as BMSCM2， on a rat model of liver cirrhosis induced by carbon tetrachloride （CCl4）/2-acetaminofluorene （2-AAF）. MethodsRat BMDMs were isolated and polarized into M2 phenotype， and rat BMSCs were isolated and co-cultured with M2-BMDMs at the third generation to obtain BMSCM2. The rats were given subcutaneous injection of CCl4 for 6 weeks to establish a model of liver cirrhosis， and then they were randomly divided into model group （M group）， BMSC group， and BMSCM2 group， with 6 rats in each group. A normal group （N group） with 6 rats was also established. Since week 7， the model rats were given 2-AAF by gavage in addition to the subcutaneous injection of CCl4. Samples were collected at the end of week 10 to observe liver function， liver histopathology， and hydroxyproline （Hyp） content in liver tissue， as well as changes in the markers for hepatic stellate cells， hepatic progenitor cells， cholangiocytes， and hepatocytes. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the N group， the M group had significant increases in the activities of serum alanine aminotransferase （ALT） and aspartate aminotransferase （AST） （P<0.01）； compared with the M group， the BMSC and BMSCM2 groups had significant reductions in ALT and AST （P<0.01）， and the BMSCM2 group had significantly better activities than the BMSC group （P<0.05）. Compared with the N group， the M group had significant increases in Hyp content and the mRNA and protein expression levels of alpha-smooth muscle actin （α-SMA） in the liver （P<0.01）； compared with the M group， the BMSC and BMSCM2 groups had significant reductions in Hyp content and the expression of α-SMA （P<0.05）， and the BMSCM2 group had a significantly lower level of α-SMA than the BMSC group （P<0.01）. Compared with the N group， the M group had significant increases in the mRNA expression levels of the hepatic progenitor cell markers EpCam and Sox9 and the cholangiocyte markers CK7 and CK19 （P<0.01） and significant reductions in the expression levels of the hepatocyte markers HNF-4α and Alb （P<0.01）； compared with the M group， the BMSC and BMSCM2 groups had significant reductions in the mRNA expression levels of EpCam， Sox9， CK7， and CK19 （P<0.05） and significant increases in the mRNA expression levels of HNF-4α and Alb （P<0.05）， and compared with the BMSC group， the BMSCM2 group had significant reductions in the mRNA expression levels of EpCam and CK19 （P<0.05） and significant increase in the expression level of HNF-4α （P<0.05）. ConclusionM2-BMDMs can enhance the therapeutic effect of BMSCs on CCl4/2-AAF-induced liver cirrhosis in rats， which provides new ideas for further improving the therapeutic effect of BMSCs on liver cirrhosis.

Research progress of mesenchymal stem cell-derived exosomes in the treatment of dry eye / 国际眼科杂志(Guoji Yanke Zazhi)

Exosomes are extracellular vesicles that facilitate cellular communication by transmitting biomolecules and altering the biochemical characteristics of receptor cells. Mesenchymal stem cell-derived exosomes(MSC-Exos)are lipid bilayer vesicles secreted by mesenchymal stem cells(MSCs). These exosomes have similar functions to MSCs and contain bioactive substances such as proteins, lipids, and nucleic acids. MSC-Exos play a vital role in intercellular communication and are involved in essential physiological processes including immune regulation, tissue damage repair, and angiogenesis promotion. Consequently, they have gained significant attention in research, particularly in the treatment of immune inflammatory diseases, ischemic diseases, and other related fields. This article provides an in-depth analysis of the potential treatment mechanisms for dry eye, focusing on the pathogenesis of the condition, including inflammatory reactions, nerve regeneration, and tissue repair. The objective is to establish a foundation for the application of MSC-Exos in the treatment of dry eye, thereby offering a valuable reference for the future clinical applications.

Research progress on immunomodulatory properties of periodontal ligament stem cells / 口腔疾病防治

@#Periodontal ligament stem cells (PDLSCs) have the potential for multidirectional differentiation and are the preferred seed cells for periodontal tissue regeneration. In recent years, a large number of studies have confirmed that PDLSCs also possess broad immunomodulatory properties. Therefore, in-depth exploration of their specific molecular mechanisms is of great significance for the treatment of periodontitis. The aim of this paper is to summarize the research progress on the regulation of PDLSCs on various immune cells and the effect of the inflammatory environment on the immune characteristics of PDLSCs to provide an important theoretical basis for the allotransplantation of PDLSCs and improve the therapeutic effect of periodontal tissue regeneration. Studies have shown that PDLSCs possess a certain degree of immunosuppressive effect on both innate and acquired immune cells, and inflammatory stimulation may lead to the impairment of the immunoregulatory properties of PDLSCs. However, current studies are mainly limited to in vitro cell tests and lack in-depth studies on the immunomodulatory effects of PDLSCs in vivo. In vivo studies based on cell lineage tracing and conditional gene knockout technology may become the main directions for future research.

Cobalt Chloride as a Hypoxia Mimicking Agent Induced HIF-1α and mTOR Expressions of Human Umbilical Cord Mesenchymal Stem Cells

ABSTRACT Objective: To assess the effects of cobalt chloride (CoCl2) as a hypoxia mimicking agent on human umbilical cord mesenchymal stem cells (hUCMSCs) expression of HIF-1α and mTOR for use in regenerative dentistry. Material and Methods: Human umbilical cord mesenchymal stem cells were isolated and then cultured. The characteristics of stemness were screened and confirmed by flow cytometry. The experiment was conducted on hypoxia (H) and normoxia (N) groups. Each group was divided and incubated into 24-, 48-, and 72-hours observations. Hypoxic treatment was performed using 100 µM CoCl2 on 5th passage cells in a conventional incubator (37°C; 5CO2). Then, immunofluorescence of HIF-1α and mTOR was done. Data was analyzed statistically using One-way ANOVA and Tukey's HSD. Results: Significant differences were found between normoxic and hypoxic groups on HIF-1α (p=0.015) and mTOR (p=0.000) expressions. The highest HIF-1α expression was found at 48 hours in the hypoxia group, while for mTOR at 24 hours in the hypoxia group. Conclusion: Hypoxia using cobalt chloride was able to increase human umbilical cord mesenchymal stem cells expression of HIF-1α and mTOR.

Morphofunctional regeneration by mesenchymal stem cell and IGF-1 inoculation in a model of facial nerve crush injury in rats

Abstract Objective: To analyze the morphofunctional regeneration process of facial nerve injury in the presence of insulin-like growth factor-1 and mesenchymal stem cells. Methods: Fourteen Wistar rats suffered unilateral facial nerve crushing and were randomly divided into two groups. All received insulin-like growth factor-1 inoculation, but only half of the animals received an additional inoculation of mesenchymal stem cells. The animals were followed for 90 days and facial nerve regeneration was analyzed via spontaneous facial motor function tests and immunohistochemistry in the nerve motor nucleus. Results: The group that received the growth factor and stem cells showed a statistically superior mean in vibrissae movements (p<0.01), touch reflex (p = 0.05) and eye closure (p<0.01), in addition to better immunohistochemistry reactivity. There was a statistically significant difference in the mean number of cells in the facial nerve nucleus between the experimental groups (p = 0.025), with the group that received the growth factor and stem cells showing the highest mean. Conclusion: The association between growth factor and stem cells potentiates the morphofunctional regeneration of the facial nerve, occurring faster and more effectively. Level of Evidence: 4, degree of recommendation C.

Effects of 970 nm diode laser irradiation on morphology, proliferation, and differentiation of gingival mesenchymal stem cells / Efectos de la irradiación con láser de diodo de 970 m sobre la morfología, la proliferación y la diferenciación de las células madre mesenquimales gingivales

Objective: The objective of this study was to investigate the morphology, proliferation, and differentiation of gingival mesenchymal stem cells (GMSCs) irradiated with a 970 nm Diode Laser (LLLT). It is essential to validate the efficacy of treatment, optimize irradiation conditions and guarantee the safety and quality of stem cells for future use in dental applications. Materials and Methods: GMSCs were cultured in standard conditions and irradiated with a Diode laser (970 nm, 0.5W) with an energy density of 9J/cm2. Cell proliferation was assessed with the WST-1 proliferation kit. GMSCs were differentiated into chondrogenic and osteogenic lineages. Cell morphology was performed with Hematoxylin/eosin staining, and quantitative nuclear analysis was done. Cell viability was monitored with trypan blue testing. Results: GMSCs subjected to irradiation demonstrated a significant increase in proliferation at 72 hours compared to the non-irradiated controls (p=0.027). This indicates that the 970 nm diode laser has a stimulatory effect on the proliferation of GMSCs. LLLT-stimulated GMSCs exhibited the ability to differentiate into chondrogenic and osteogenic lineages. A substantial decrease in cell viability was observed 24 hours after irradiation (p=0.024). However, after 48 hours, the cell viability recovered without any significant differences. This indicates that there might be a temporary negative impact on cell viability immediately following irradiation, but the cells were able to recover and regain their viability over time. Conclusions: This study support that irradiation with a 970 nm diode laser could stimulate the proliferation of GMSCs, maintain their ability to differentiate into chondrogenic and osteogenic lineages, and has minimal impact on the mor- phological characteristics of the cells. These results support the potential use of NIR Lasers in combination with GMSCs as a promising strategy for dental treatments.

Objetivo: El objetivo de este estudio fue investigar la morfología, proliferación y diferenciación de las células madre mesenquimatosas (GMSC) irradiadas con un láser de diodo de 970 nm (LLLT). Es fundamental validar la eficacia del tratamiento, optimizar las condiciones de irradiación y garantizar la seguridad y calidad de las células madre para su uso futuro en aplicaciones dentales.Materiales y Métodos: Las GMSC se cultivaron en condiciones estándar y se irradiaron con un láser de diodo (970 nm, 0,5 W) con una densidad de energía de 9 J/cm2. La proliferación celular se evaluó con el kit de proliferación WST-1. Las GMSC se diferenciaron en linajes condrogénicos y osteogénicos. La morfología celular se realizó con tinción de hematoxilina/eosina y se realizó un análisis nuclear cuantitativo. La viabilidad celular se controló con prueba de azul de tripano. Resultados: Las GMSC sometidas a irradiación demostraron un aumento significativo en la proliferación a las 72 horas en comparación con los controles no irradiados (p=0,027). Esto indica que el láser de diodo de 970 nm tiene un efecto estimulante sobre la proliferación de GMSC. Las GMSC estimuladas con LLLT exhibieron la capacidad de diferenciarse en linajes condrogénicos y osteogénicos. Se observó una disminución sustancial de la viabilidad celular 24 horas después de la irradiación (p=0,024). Sin embargo, después de 48 horas, la viabilidad celular se recuperó sin diferencias significativas. Esto indica que podría haber un impacto negativo temporal en la viabilidad de las células inmediatamente después de la irradiación, pero las células pudieron recuperarse y recuperar su viabilidad con el tiempo. Conclusión: En conclusión, este estudio respalda que la irradiación con un láser de diodo de 970 nm podría estimular la proliferación de GMSC, mantener su capacidad para diferenciarse en linajes condrogénicos y osteogénicos y tiene un impacto mínimo en las características morfológicas de las células. Estos resultados respaldan el uso potencial de láseres NIR en combinación con GMSC como una estrategia prometedora para tratamientos dentales.

Stem cell-derived exosomes from human exfoliated deciduous teeth promote angiogenesis in hyperglycemic-induced human umbilical vein endothelial cells

Abstract Objective To investigate the angiogenesis in human umbilical vein endothelial cells (HUVEC) under high glucose concentration, treated with exosomes derived from stem cells from human exfoliated deciduous teeth (SHED). Methodology SHED-derived exosomes were isolated by differential centrifugation and were characterized by nanoparticle tracking analysis, transmission electron microscopy, and flow cytometric assays. We conducted in vitro experiments to examine the angiogenesis in HUVEC under high glucose concentration. Cell Counting Kit-8, migration assay, tube formation assay, quantitative real-time PCR, and immunostaining were performed to study the role of SHED-derived exosomes in cell proliferation, migration, and angiogenic activities. Results The characterization confirmed SHED-derived exosomes: size ranged from 60-150 nm with a mode of 134 nm, cup-shaped morphology, and stained positively for CD9, CD63, and CD81. SHED-exosome significantly enhanced the proliferation and migration of high glucose-treated HUVEC. A significant reduction was observed in tube formation and a weak CD31 staining compared to the untreated-hyperglycemic-induced group. Interestingly, exosome treatment improved tube formation qualitatively and demonstrated a significant increase in tube formation in the covered area, total branching points, total tube length, and total loop parameters. Moreover, SHED-exosome upregulates angiogenesis-related factors, including the GATA2 gene and CD31 protein. Conclusions Our data suggest that the use of SHED-derived exosomes potentially increases angiogenesis in HUVEC under hyperglycemic conditions, which includes increased cell proliferation, migration, tubular structures formation, GATA2 gene, and CD31 protein expression. SHED-exosome usage may provide a new treatment strategy for periodontal patients with diabetes mellitus.

Human umbilical cord mesenchymal stem cells accelerate and increase implant osseointegration in diabetic rats

Abstract Objective This study was conducted to assess the effect of hUCMSCs injection on the osseointegration of dental implant in diabetic rats via Runt-related Transcription Factor 2 (Runx2), Osterix (Osx), osteoblasts, and Bone Implant Contact (BIC). Methodology The research design was a true experimental design using Rattus norvegicus Wistar strain. Rattus norvegicus were injected with streptozotocin to induce experimental diabetes mellitus. The right femur was drilled and loaded with titanium implant. Approximately 1 mm from proximal and distal implant site were injected with hUCMSCs. The control group was given only gelatin solvent injection. After 2 and 4 weeks of observation, the rats were sacrificed for further examination around implant site using immunohistochemistry staining (RUNX2 and Osterix expression), hematoxylin eosin staining, and bone implant contact area. Data analysis was done using ANOVA test. Results Data indicated a significant difference in Runx2 expression (p<0.001), osteoblasts (p<0.009), BIC value (p<0.000), and Osterix expression (p<0.002). In vivo injection of hUCMSCs successfully increased Runx2, osteoblasts, and BIC value significantly, while decreased Osterix expression, indicating an acceleration of the bone maturation process. Conclusion The results proved hUCMSCs to accelerate and enhance implant osseointegration in diabetic rat models.

Bone marrow-derived mesenchymal stem cell-conditioned medium ameliorates diabetic foot ulcers in rats

Abstract Objectives: This study aimed to explore the effects of bone marrow-derived Mesenchymal Stem Cell-Conditioned Medium (MSC-CM) treating diabetic foot ulcers in rats. Methods: Models of T2DM rats were induced by a high-fat diet and intraperitoneal injection of STZ in SD rats. Models of Diabetic Foot Ulcers (DFUs) were made by operation on hind limbs in diabetic rats. Rats were divided into four groups (n = 6 for each group), i.e., Normal Control group (NC), Diabetes Control group (DM-C), MSC-CM group and Mesenchymal Stem Cells group (MSCs). MSC-CM group was treated with an injection of conditioned medium derived from preconditioned rats' bone marrow MSCs around ulcers. MSCs group were treated with an injection of rats' bone marrow MSCs. The other two groups were treated with an injection of PBS. After the treatment, wound closure, re-epithelialization (thickness of the stratum granulosums of the skin, by H&E staining), cell proliferation (Ki67, by IHC), angiogenesis (CD31, by IFC), autophagy (LC3B, by IFC and WB; autoly-sosome, by EM) and pyroptosis (IL-1β, NLRP3, Caspase-1, GSDMD and GSDMD-N, by WB) in ulcers were evaluated. Results: After the treatment wound area rate, IL-1β by ELISA, and IL-1β, Caspase-1, GSDMD and GSDMD-N by WB of MSC-CM group were less than those of DM group. The thickness of the stratum granulosums of the skin, proliferation index of Ki67, mean optic density of CD31 and LC3B by IFC, and LC3B by WB of MSC-CM group were more than those of DM group. The present analysis demonstrated that the injection of MSC-CM into rats with DFUs enhanced the wound-healing process by accelerating wound closure, promoting cell proliferation and angiogenesis, enhancing cell autophagy, and reducing cell pyroptosis in ulcers. Conclusions: Studies conducted indicate that MSC-CM administration could be a novel cell-free therapeutic approach to treat DFUs accelerating the wound healing process and avoiding the risk of living cells therapy.

Protease-activated receptor type 2 activation downregulates osteogenesis in periodontal ligament stem cells

Abstract Protease-activated receptor-2 (PAR2) is associated with the pathogenesis of many chronic diseases with inflammatory characteristics, including periodontitis. This study aimed to evaluate how the activation of PAR2 can affect the osteogenic activity of human periodontal ligament stem cells (PDLSCs) in vitro. PDLSCs collected from three subjects were treated in osteogenic medium for 2, 7, 14, and 21 days with trypsin (0.1 U/mL), PAR2 specific agonist peptide (SLIGRL-NH2) (100 nM), and PAR2 antagonist peptide (FSLLRY-NH2) (100 nM). Gene (RT-qPCR) expression and protein expression (ELISA) of osteogenic factors, bone metabolism, and inflammatory cytokines, cell proliferation, alkaline phosphatase (ALP) activity, alizarin red S staining, and supernatant concentration were assessed. Statistical analysis of the results with a significance level of 5% was performed. Activation of PAR2 led to decreases in cell proliferation and calcium deposition (p < 0.05), calcium concentration (p < 0.05), and ALP activity (p < 0.05). Additionally, PAR2 activation increased gene and protein expression of receptor activator of nuclear factor kappa-Β ligand (RANKL) (p < 0.05) and significantly decreased the gene and protein expression of osteoprotegerin (p <0. 05). Considering the findings, the present study demonstrated PAR2 activation was able to decrease cell proliferation, decreased osteogenic activity of PDLSCs, and upregulated conditions for bone resorption. PAR2 may be considered a promising target in periodontal regenerative procedures.

Mesenchymal stem cells-derived exosomal miR-653-5p suppresses laryngeal papilloma progression by inhibiting BZW2

Abstract Objectives: Although miR-653-5p has been validated to participate in the progression of multiple types of cancer, the functional role of exosomal miR-653-5p derived from Mesenchymal Stem Cells (MSCs) in Laryngeal Papilloma (LP) has still remained elusive. Hence, this study aimed to investigate the role of MSCs-derived exosomal miR-653-5p in LP. Methods: LP tissues (n = 15) and adjacent normal tissues (n = 10) were collected to examine the expression level of miR-653-5p. The expression level of miR-653-5p in LP cells and normal cells was also detected. Then, miR-653-5p was overexpressed or silenced to explore its effects on the proliferation, migration, invasion, and apoptosis of LP cells. Thereafter, the effects of exosomal miR-653-5p derived from MSCs on LP cell progression and the potential regulatory mechanism of miR-653-5p were assessed. Results: It was revealed that the expression level of miR-653-5p was downregulated in LP tissues and cells. In addition, miR-653-5p suppressed the proliferation, migration, invasion, and apoptosis of LP cells. Exosomes derived from MSCs played a suppressive role in LP development and mediated the transmission of miR-653-5p to LP cells. Further exploration identified Basic leucine Zipper and W2 domains 2 (BZW2) as the target of miR-653-5p. More importantly, the rescue experiments revealed that MSCs-secreted exosomal miR-653-5p efficiently inhibited the aggressive phenotypes of LP cells, which could be significantly reversed by BZW2 overexpression in LP cells. Conclusion: MSCs-derived exosomal miR-653-5p exerted inhibitory effects on LP progression through targeting BZW2, which provided a novel idea for the therapy of LP. Clinical Trial registration number: chictr-ior-17011021.

Research progress in the role of mesenchymal stem cell sheets and their derivatives in bone defect repair / 中华创伤杂志

Bone defects are mostly caused by severe trauma, infection, tumor resection and congenital malformations, which adversely affect their health and quality of life. So far, the bone defects are mainly filled with autologous or allogeneic bone grafting, which has problems such as donor shortage, secondary bone injury and scarring. In recent years, the rise of bone tissue engineering has provided a new way for repair of bone defects, in which mesenchymal stem cell (MSC) sheets prepared by using the principle of tissue engineering can well solve the above problems of autologous or allogeneic bone grafting. With the development of preparation technology, new bone defect repair materials such as decellularized extracellular matrix (ECM) sheets and MSC/ECM clumps have been derived on the basis of MSC sheets. Therefore, the authors reviewed the preparation and the role of MSC sheets and their derivatives in bone defect repair, hoping to provide a reference for basic research and clinical treatment related to bone defect repair.

Research progress in mechanism of action and application of mesenchymal stem cell-derived exosomes in repair of bone defects / 中华创伤杂志

Bone defects are bone loss caused by factors such as severe trauma, infection, tumor resection and congenital malformations. Bone transplantation, induced membrane technique or stem cell bone tissue engineering is needed for the defects that are difficult to heal naturally. However, the techniques related to bone transplantation are complex and have limited application scope; the induced membrane technique shows uncontrollable cement degradation rate and requires a second surgery; the stem cell bone tissue engineering still has some unstable factors such as undirected differentiation of stem cells. Exosomes are the key liposomes in the communication between cells. Compared with natural stem cell-derived exosomes, engineered exosomes with the advantages of high production and low immunogenicity are expected to replace stem cells in clinical applications. The authors review the mechanism of action of mesenchymal stem cell (MSC)-derived exosomes in repairing bone defects and application of engineered exosomes based on MSC in bone regeneration, so as to provide new ideas for the basic research and clinical treatment of bone defects.

Bone marrow mesenchymal stem cell-derived exosomal miR-30e-5p ameliorates high-glucose induced renal proximal tubular cell pyroptosis / 西安交通大学学报(医学版)

【Objective】 To study the effects of miR-30e-5p from bone marrow mesenchymal stem cell-derived exosomes(BMSC-exos) on high glucose (HG)-induced HK-2 cell pyroptosis and explore an alternative strategy to manage diabetic kidney disease (DKD). 【Methods】 BMSC-exos were isolated and internalized into HK-2 cells treated with HG to measure viability and cytotoxicity. The secretion of IL-1β and IL-18 was measured by ELISA. Pyroptosis was assessed by flow cytometry. The levels of miR-30e-5p, IL-1β, and IL-18 were measured. The expression of pyroptosis-associated cytokine proteins was determined. 【Results】 BMSC-exos decreased LDH, IL-1β, and IL-18 secretion and inhibited the expression of the pyroptosis-related factors (IL-1β, caspase-1, GSDMD-N, and NLRP3) in HG-induced HK-2 cells. Moreover, miR-30e-5p depletion in BMSC-exos promoted HK-2 cell pyroptosis. 【Conclusion】 BMSC-derived exosomal miR-30e-5p inhibits caspase-1-mediated pyroptosis in HG-induced HK-2 cells, which might provide a new strategy for treating DKD.

Research advances in mesenchymal stem cells and their exosomes in treatment of autoimmune hepatitis / 临床肝胆病杂志

Autoimmune hepatitis （AIH） is a type of chronic hepatitis caused by the autoimmune system attacking hepatocytes， and its chronic progression may lead to liver cirrhosis and even hepatocellular carcinoma. Currently， pharmacotherapy and liver transplantation are the main treatment methods for AIH， but both methods have their own limitations， which limits the clinical benefits of patients. Therefore， it is a critical issue to search for new therapeutic agents and methods. Recent studies have shown that mesenchymal stem cells （MSC） and their exosomes can improve the symptoms of patients with AIH by suppressing inflammatory response， enhancing the regeneration of hepatocytes， and regulating the immune system and thus have wide application prospects in the treatment of AIH. By summarizing related articles， this article reviews the possible mechanisms and application of MSC and their exosomes in the treatment of AIH， in order to provide new ideas for the clinical treatment of AIH.

Chinese Medicine Regulates Signaling Pathways Related to Proliferation and Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells： A Review / 中国实验方剂学杂志

Bone marrow mesenchymal stem cells （BMSCs） are derived from stem cells isolated from bone marrow and have the potential for multidirectional differentiation and self-renewal. Under certain conditions， BMSCs can be induced to differentiate into osteoblast （OB）， chondrocyte， adipocyte， fibroblast， etc. BMSCs play an important role in maintaining the stability of bone structure and balancing bone metabolism. Promoting the proliferation of BMSCs and inducing their differentiation into OB of great significance for the clinical prevention and treatment of osteoporosis， bone defects， fracture healing， and other diseases. Because the proliferation and osteogenic differentiation of BMSCs are complex processes controlled by multiple genes and regulated by multiple signal transduction pathways， traditional Chinese medicine （TCM） happens to have the advantages of multi-bioactive component， multi-target， and multi-pathway synergism， which can affect the proliferation and differentiation of BMSCs through multiple channels and induce the proliferation of BMSCs. The transcription and expression of genes related to osteogenesis can be enhanced to promote the differentiation of BMSCs into OB， so as to achieve the purpose of preventing and treating osteoporosis， bone defects， and other bone diseases. Based on the literature on the intervention of TCM monomers and compounds in the proliferation and osteogenic differentiation of BMSCs， this study reviewed TCM monomers and compounds in promoting the proliferation and osteogenic differentiation of BMSCs by regulating secreted glycoprotein （Wnt）， neurogenic locus notch homolog protein （Notch）， mitogen-activated protein kinase （MAPK）， phosphatidylinositol-3 kinase （PI3K） /protein kinase B （Akt）， bone morphogenetic protein （BMP）/Smad， Janus kinase （JAK）/signal transducer and activator of transcription protein （STAT）， osteoprotegerin （OPG）/receptor activator of nuclear factor-kappa B （RANK）/RANK ligand （RANKL）， and other signaling pathways to provide new ideas for the research and clinical application of Chinese medicine in the prevention and treatment of orthopedic diseases.

Transplanting bone marrow mesenchymal stem cells can induce neural regeneration / 中华物理医学与康复杂志

Objective:To observe any effect of transplanting bone marrow mesenchymal stem cells (BMSCs) on microglia and neuron expression in newborn mice with hypoxic-ischemic brain damage (HIBD).Methods:Sixty 10-day-old C57BL/6 mice were randomly divided into a sham operation group, a hypoxic-ischemia group, a placebo group and a stem cell group, each of 15. The hypoxia-ischemia model was induced in the hypoxia-ischemia, placebo and stem cell groups, while the sham operation group was sutured after the neck incision. After successful modeling, the rats in the stem cell group were injected with BMSCs into the bregma while those in the placebo group received phosphate buffered saline. Seven days later, brain tissue was resected and its structure was observed using transmission electron microscopy. Immunofluorescence staining was performed to observe the expression of microglia and neurons in the left cerebral cortex.Results:Seven days after stem cell transplantation, the neuron morphology had improved and nerve fiber swelling was relieved in the stem cell group. The average expression of neurons was significantly greater in the stem cell group compared with the hypoxic-ischemia and placebo groups, while the expression of microglia was significantly lower.Conclusions:Bone marrow mesenchymal stem cells may induce neuron regeneration and reduce inflammatory response by inhibiting the expression of microglia, at least in neonatal rats modeling hypoxic-ischemic brain injury.

Research advance of mesenchymal stem cell-derived exosomes in graft-versus-host disease / 中华器官移植杂志

Mesenchymal stem cells (MSCs) are pluripotent stem cells with self-renewing differentiation, immunoactivity and anti-inflammatory potentials.Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is currently the most effective treatment for hematologic malignancies.However, the presence of graft-versus-host disease (GVHD) after transplantation has hindered the development of allo-HSCT.MSC-derived exosomes (MSC-exo) derived from mesenchymal stem cells have been confirmed to have broad therapeutic prospects in allo-HSCT and GVHD.This review focused upon immunomodulatory effects of MSC, biological activities of MSC-exo and research advances of MSC-exo on managing GVHD, aiming to provide new therapeutic rationales for GVHD in the future.