Potencial das membranas de células-tronco mesenquimais na regeneração periodontal: uma revisão sistemática de estudos pré-clínicos em modelo animal / Potential of mesenchymal stem cell sheets on periodontal regeneration: a systematic review of pre-clinical animal studies

A periodontite é uma doença inflamatória crônica multifactorial caracterizada pela destruição progressiva do aparelho de suporte periodontal. Atualmente, as técnicas convencionais para regeneração desses tecidos periodontais perdidos tiveram sucesso limitado. A tecnologia de membranas de células usando células-tronco mesenquimais apareceu como uma estratégia promissora na medicina regenerativa periodontal. Embora estudos recentes tenham mostrado o papel das membranas de células-tronco mesenquimais (MSCSs) no aumento dos tecidos de suporte dentário e ósseo, não há uma revisão sistemática focada especificamente na avaliação da regeneração periodontal em modelos animais ortotópicos. Esta revisão tem como objetivo avaliar o potencial das MSCSs na regeneração periodontal em comparação ao controle, em modelos animais experimentais. Estudos pré-clínicos em defeitos periodontais de modelos animais foram considerados elegíveis. A busca eletrônica incluiu as bases de dados MEDLINE, Web of Science, EMBASE e LILACS. Além disso, uma busca manual avaliou as revistas científicas na área de periodontia/regeneração. A revisão sistemática foi conduzida de acordo com as diretrizes de Preferred Reporting Item for Systematic Reviews and Meta-Analyses statement guidelines. A ferramenta do Centro de Revisão Sistemática para Experimentação com Animais de Laboratório (SYRCLE) foi usada para avaliar o risco de viés. Dos 3989 estudos obtidos a partir da busca no banco de dados eletrônicos foram incluídos 17 artigos. Foram empregados MSCSs autólogos, alógenos e xenógenos para melhorar a regeneração periodontal. Estes incluíram MSCSs do folículo dentário (DF), MSCSs do ligamento periodontal (PDL), MSCSs da polpa dentária (DP), MSCSs da medula óssea (BM), MSCSs periosteais alveolares (AP) e MSCSs gengivais (G). Em relação ao protocolo de indução de células, a maioria dos estudos utilizou ácido ascórbico (52,94%), outros utilizaram placas de cultura com polímero termo responsivo (47,06%). Os efeitos adversos, em relação à utilização das MSCSs no sítio doador, não foram identificados na maioria dos estudos, mesmo com o uso adjunto de scaffolds, membranas ou ambos. Meta-análise não foi considerada devido a heterogeneidades metodológicas. PDL-MSCSs demonstrou ser superior para aumento da regeneração periodontal em comparação ao controle, mas em um microambiente inflamatório induzido, DF-MSCSs foram melhores. Os DF-MSCSs parecem estar relacionados à espessura do cemento e dimensão periodontal. Além disso, DP-MSCSs e BM-MSCSs mostraram resultados melhores em comparação com o controle. Em contraste, AP-MSCSs não foram associados a melhorias na regeneração periodontal. A avaliação do risco de viés com a ferramenta da SYRCLE revelou que 44,12% dos estudos apresentavam baixo risco de viés, 55,29% foram incertos e 0,59%, alto risco. A presente revisão sistemática mostrou que as MSCSs podem aumentar a regeneração periodontal em modelos animais de defeito periodontal, fornecendo uma estratégia promissora para aumentar a regeneração periodontal.

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.

Endometrial mesenchymal stromal/stem cells improve regeneration of injured endometrium in mice

BACKGROUND: The monthly regeneration of human endometrial tissue is maintained by the presence of human endometrial mesenchymal stromal/stem cells (eMSC), a cell population co-expressing the perivascular markers CD140b and CD146. Endometrial regeneration is impaired in the presence of intrauterine adhesions, leading to infertility, recurrent pregnancy loss and placental abnormalities. Several types of somatic stem cells have been used to repair the damaged endometrium in animal models, reporting successful pregnancy. However, the ability of endometrial stem cells to repair the damaged endometrium remains unknown. METHODS: Electrocoagulation was applied to the left uterine horn of NOD/SCID mice causing endometrial injury. Human eMSC or PBS was then injected into the left injured horn while the right normal horn served as controls. Mice were sacrificed at different timepoints (Day 3, 7 and 14) and the endometrial morphological changes as well as the degree of endometrial injury and repair were observed by histological staining. Gene expression of various inflammatory markers was assessed using qPCR. The functionality of the repaired endometrium was evaluated by fertility test. RESULTS: Human eMSC successfully incorporated into the injured uterine horn, which displayed significant morphological restoration. Also, endometrium in the eMSC group showed better cell proliferation and glands formation than the PBS group. Although the number of blood vessels were similar between the two groups, gene expression of VEGF-α significantly increased in the eMSC group. Moreover, eMSC had a positive impact on the regeneration of both stromal and epithelial components of the mouse endometrium, indicated by significantly higher vimentin and CK19 protein expression. Reduced endometrial fibrosis and down-regulation of fibrosis markers were also observed in the eMSC group. The eMSC group had a significantly higher gene expression of anti-inflammatory factor Il-10 and lower mRNA level of pro-inflammatory factors Ifng and Il-2, indicating the role of eMSC in regulation of inflammatory reactions. The eMSC group showed higher implantation sites than the PBS group, suggesting better endometrial receptivity with the presence of newly emerged endometrial lining. CONCLUSIONS: Our findings suggest eMSC improves regeneration of injured endometrium in mice.

Fibroblasts inhibit osteogenesis by regulating nuclear-cytoplasmic shuttling of YAP in mesenchymal stem cells and secreting DKK1

BACKGROUND: Fibrous scars frequently form at the sites of bone nonunion when attempts to repair bone fractures have failed. However, the detailed mechanism by which fibroblasts, which are the main components of fibrous scars, impede osteogenesis remains largely unknown. RESULTS: In this study, we found that fibroblasts compete with osteogenesis in both human bone nonunion tissues and BMP2-induced ectopic osteogenesis in a mouse model. Fibroblasts could inhibit the osteoblastic differentiation of mesenchymal stem cells (MSCs) via direct and indirect cell competition. During this process, fibroblasts modulated the nuclear-cytoplasmic shuttling of YAP in MSCs. Knocking down YAP could inhibit osteoblast differentiation of MSCs, while overexpression of nuclear-localized YAP-5SA could reverse the inhibition of osteoblast differentiation of MSCs caused by fibroblasts. Furthermore, fibroblasts secreted DKK1, which further inhibited the formation of calcium nodules during the late stage of osteogenesis but did not affect the early stage of osteogenesis. Thus, fibroblasts could inhibit osteogenesis by regulating YAP localization in MSCs and secreting DKK1. CONCLUSIONS: Our research revealed that fibroblasts could modulate the nuclear-cytoplasmic shuttling of YAP in MSCs, thereby inhibiting their osteoblast differentiation. Fibroblasts could also secrete DKK1, which inhibited calcium nodule formation at the late stage of osteogenesis.

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.

The expression mechanism of programmed cell death 1 ligand 1 and its role in immunomodulatory ability of mesenchymal stem cells / 中华创伤杂志(英文版)

Programmed cell death 1 ligand 1 (PD-L1) is an important immunosuppressive molecule, which inhibits the function of T cells and other immune cells by binding to the receptor programmed cell death-1. The PD-L1 expression disorder plays an important role in the occurrence, development, and treatment of sepsis or other inflammatory diseases, and has become an important target for the treatment of these diseases. Mesenchymal stem cells (MSCs) are a kind of pluripotent stem cells with multiple differentiation potential. In recent years, MSCs have been found to have a strong immunosuppressive ability and are used to treat various inflammatory insults caused by hyperimmune diseases. Moreover, PD-L1 is deeply involved in the immunosuppressive events of MSCs and plays an important role in the treatment of various diseases. In this review, we will summarize the main regulatory mechanism of PD-L1 expression, and discuss various biological functions of PD-L1 in the immune regulation of MSCs.

Advances in mesenchymal stem cells therapy for tendinopathies / 中华创伤杂志(英文版)

Tendinopathies are chronic diseases of an unknown etiology and associated with inflammation. Mesenchymal stem cells (MSCs) have emerged as a viable therapeutic option to combat the pathological progression of tendinopathies, not only because of their potential for multidirectional differentiation and self-renewal, but also their excellent immunomodulatory properties. The immunomodulatory effects of MSCs are increasingly being recognized as playing a crucial role in the treatment of tendinopathies, with MSCs being pivotal in regulating the inflammatory microenvironment by modulating the immune response, ultimately contributing to improved tissue repair. This review will discuss the current knowledge regarding the application of MSCs in tendinopathy treatments through the modulation of the immune response.

Impact of lithocholic acid on the osteogenic and adipogenic differentiation balance of bone marrow mesenchymal stem cells / 中国修复重建外科杂志

OBJECTIVE@#To Investigate the effects of lithocholic acid (LCA) on the balance between osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs).@*METHODS@#Twelve 10-week-old SPF C57BL/6J female mice were randomly divided into an experimental group (undergoing bilateral ovariectomy) and a control group (only removing the same volume of adipose tissue around the ovaries), with 6 mice in each group. The body mass was measured every week after operation. After 4 weeks post-surgery, the weight of mouse uterus was measured, femur specimens of the mice were taken for micro-CT scanning and three-dimensional reconstruction to analyze changes in bone mass. Tibia specimens were taken for HE staining to calculate the number and area of bone marrow adipocytes in the marrow cavity area. ELISA was used to detect the expression of bone turnover markers in the serum. Liver samples were subjected to real-time fluorescence quantitative PCR (RT-qPCR) to detect the expression of key genes related to bile acid metabolism, including cyp7a1, cyp7b1, cyp8b1, and cyp27a1. BMSCs were isolated by centrifugation from 2 C57BL/6J female mice (10-week-old). The third-generation cells were exposed to 0, 1, 10, and 100 μmol/L LCA, following which cell viability was evaluated using the cell counting kit 8 assay. Subsequently, alkaline phosphatase (ALP) staining and oil red O staining were conducted after 7 days of osteogenic and adipogenic induction. RT-qPCR was employed to analyze the expressions of osteogenic-related genes, namely ALP, Runt-related transcription factor 2 (Runx2), and osteocalcin (OCN), as well as adipogenic-related genes including Adiponectin (Adipoq), fatty acid binding protein 4 (FABP4), and peroxisome proliferator-activated receptor γ (PPARγ).@*RESULTS@#Compared with the control group, the body mass of the mice in the experimental group increased, the uterus atrophied, the bone mass decreased, the bone marrow fat expanded, and the bone metabolism showed a high bone turnover state. RT-qPCR showed that the expressions of cyp7a1, cyp8b1, and cyp27a1, which were related to the key enzymes of bile acid metabolism in the liver, decreased significantly ( P<0.05), while the expression of cyp7b1 had no significant difference ( P>0.05). Intervention with LCA at concentrations of 1, 10, and 100 μmol/L did not demonstrate any apparent toxic effects on BMSCs. Furthermore, LCA inhibited the expressions of osteogenic-related genes (ALP, Runx2, and OCN) in a dose-dependent manner, resulting in a reduction in ALP staining positive area. Concurrently, LCA promoted the expressions of adipogenic-related genes (Adipoq, FABP4, and PPARγ), and an increase in oil red O staining positive area.@*CONCLUSION@#After menopause, the metabolism of bile acids is altered, and secondary bile acid LCA interferes with the balance of osteogenic and adipogenic differentiation of BMSCs, thereby affecting bone remodelling.

Avaliação in vitro da fotobiomodulação das SHEDs semeadas em um scaffold de osso bovino mineral desproteinizado e colagenado / In vitro evaluation of photobiomodulation of Stem cells from human exfoliated deciduous teeth seeded in a deproteinized bovine bone mineral with 10% collagen scaffold

A regeneração óssea é um processo importante para oferecer tratamentos reconstrutivos mais rápidos e eficientes, no entanto, limitações técnicas continuam sendo um desafio, assim como a velocidade de formação e maturação óssea. Portanto, as pesquisas têm se voltado para técnicas alternativas na regeneração óssea e atualmente, a engenharia tecidual tem estudado o uso de células tronco para tratamento de perdas ósseas. A eficácia e a taxa de sucesso das diferentes técnicas e scaffolds foram avaliadas. Porém, há pouca informação sobre a eficácia combinada de carreadores xenógenos, células tronco de dentes decíduos esfoliados humano (SHEDs) e a terapia de fotobiomodulação (PBMT) na regeneração de defeitos ósseos. Baseado em estudos prévios, a proposta deste estudo foi avaliar, in vitro, a ação da PBMT, uma técnica com propriedades imunomodulatórias, angiogênicas e com capacidade de aumentar a adesão, proliferação e migração celular ao biomaterial tridimensional de osso bovino mineralizado desproteinizado com colágeno suíno a 10% (OBMDC), semeado com SHEDs, para acelerar e aumentar a taxa de formação óssea. Foi utilizado o laser de diodo, com comprimento de onda de 660nm; 40mW de potência; 3J/cm2 de densidade de energia e 2 segundos de tempo de aplicação após 24h e 72h do plaqueamento. Para avaliar a proliferação, as SHEDs foram descongeladas cultivadas, plaqueadas, semeadas no scaffold de OBMDC e divididas em 8 grupos: 1) Controle 15%; 2) Controle 5%; 3) OBMDC 15%; 4) OBMDC 5%; 5) Laser 15%; 6) Laser 5%; 7) OBMDC-L 15%; 8) OBMDC-L 5% e a análise de proliferação foi realizada por MTT. Para avaliar diferenciação celular, as amostras foram divididas em quatro grupos: 1) Grupo Controle clonogênico: SHEDs cultivadas em meio clonogênico; 2) Grupo Controle mineralizante: SHEDs cultivadas em meio mineralizante; 3) Grupo laser clonogênico: SHEDs cultivadas em meio clonogênico com aplicação de laser; 4) Grupo laser mineralizante: SHEDs cultivada em meio mineralizante com aplicação de laser. Para o grupo laser, as células foram irradiadas no período de 24h e 72h após o plaqueamento e todas as amostras fixadas para análise da formação dos depósitos de cálcio, através do ensaio de vermelho de alizarina após 23 dias de cultivo celular e os dados foram tratados estatisticamente (p0,05). Para avaliar a morfologia celular das SHEDs em todos os grupos, utilizou-se o microscópio invertido de fase em 24h e 72h após o plaqueamento. O grupo OBMDC-L 5% SFB em 72h, demonstrou maior proliferação celular que o grupo Controle (p=0.0286). O grupo laser no meio mineralizante apresentou maior formação de depósito de matriz mineralizada em comparação ao grupo controle em meio clonogênico, controle em meio mineralizante e laser em meio clonogênico (p<0,0001). Considerando as condições experimentais deste estudo, concluiu-se que, in vitro, as SHEDs, semeadas em scaffold OBMDC, proliferaram mais após 2 aplicações de PBMT e houve diferenciação osteogênica das células após 23 dias em meio mineralizante.

Injection of freshly collected adipose tissue for the treatment complex cryptoglandular anal fistula: case report

Introduction: Perianal fistula is a common colorectal disease which is caused mainly by cryptoglandular disease. Although most cases are treated successfully by surgery, management of complex perianal fistulas (CPAF) remains a challenge with limited results in recurrence and sometimes associated with fecal incontinence. The CPAF treatment with autologous adipose-derived mesenchymal stem cells (ASCs) had become a research hotspot. The technique started to be used in the treatment of Crohn's disease (CD) fistulas, where the studies showed safe and goods result from the procedure. Cultured ASCs have been used but this approach requires the preceding collection of adipose tissue, time for isolation of ASCs and subsequent in vitro expansion, need for laboratory facilities, and expertise in cell culturing. These factors have been getting over by using the commercially available alternative, allogenic ASCs. Treatment with allogeneic ASCs has shown good results in patients with CD fistulas, however with the disadvantage of being expensive. Objective: To show that the injection with freshly collected adipose tissue is an alternative to treatment with autologous or allogenic ASCs with several advantages. Methods: In this case report, we show our first experience in the treatment of CPAF with the application of collected adipose tissue in a tertiary referral hospital from Belo Horizonte, Brazil. Results The patient had a good postoperative recuperation with a complete fistula healing after 8 months without adverse effects. Conclusion: Injection with freshly collected adipose tissue is a promising and apparently safe sphincter-sparing technique in the treatment of CPAF. (AU)

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.

Spontaneous spheroids from alveolar bone-derived mesenchymal stromal cells maintain pluripotency of stem cells by regulating hypoxia-inducible factors

BACKGROUND: Spontaneous spheroid culture is a novel three-dimensional (3D) culture strategy for the rapid and efficient selection of progenitor cells. The objectives of this study are to investigate the pluripotency and differentiation capability of spontaneous spheroids from alveolar bone-derived mesenchymal stromal cells (AB-MSCs); compare the advantages of spontaneous spheroids to those of mechanical spheroids; and explore the mechanisms of stemness enhancement during spheroid formation from two-dimensional (2D) cultured cells. METHODS: AB-MSCs were isolated from the alveolar bones of C57BL/6 J mice. Spontaneous spheroids formed in low-adherence specific culture plates. The stemness, proliferation, and multi-differentiation capacities of spheroids and monolayer cultures were investigated by reverse transcription quantitative polymerase chain reaction (RT-qPCR), immunofluorescence, alkaline phosphatase (ALP) activity, and oil-red O staining. The pluripotency difference between the spontaneous and mechanical spheroids was analyzed using RT-qPCR. Hypoxia-inducible factor (HIFs) inhibition experiments were performed to explore the mechanisms of stemness maintenance in AB-MSC spheroids. RESULTS: AB-MSCs successfully formed spontaneous spheroids after 24 h. AB-MSC spheroids were positive for MSC markers and pluripotency markers (Oct4, KLF4, Sox2, and cMyc). Spheroids showed higher Ki67 expression and lower Caspase3 expression at 24 h. Under the corresponding conditions, the spheroids were successfully differentiated into osteogenic and adipogenic lineages. AB-MSC spheroids can induce neural-like cells after neurogenic differentiation. Higher expression of osteogenic markers, adipogenic markers, and neurogenic markers (NF-M, NeuN, and GFAP) was found in spheroids than in the monolayer. Spontaneous spheroids exhibited higher stemness than mechanical spheroids did. HIF-1α and HIF-2α were remarkably upregulated in spheroids. After HIF-1/2α-specific inhibition, spheroid formation was significantly reduced. Moreover, the expression of the pluripotency genes was suppressed. CONCLUSIONS: Spontaneous spheroids from AB-MSCs enhance stemness and pluripotency. HIF-1/2α plays an important role in the stemness regulation of spheroids. AB-MSC spheroids exhibit excellent multi-differentiation capability, which may be a potent therapy for craniomaxillofacial tissue regeneration.

DNA methylation analysis identifies key transcription factors involved in mesenchymal stem cell osteogenic differentiation

BACKGROUND: Knowledge about regulating transcription factors (TFs) for osteoblastogenesis from mesenchymal stem cells (MSCs) is limited. Therefore, we investigated the relationship between genomic regions subject to DNA-methylation changes during osteoblastogenesis and the TFs known to directly interact with these regulatory regions. RESULTS: The genome-wide DNA-methylation signature of MSCs differentiated to osteoblasts and adipocytes was determined using the Illumina HumanMethylation450 BeadChip array. During adipogenesis no CpGs passed our test for significant methylation changes. Oppositely, during osteoblastogenesis we identified 2462 differently significantly methylated CpGs (adj. p < 0.05). These resided outside of CpGs islands and were significantly enriched in enhancer regions. We confirmed the correlation between DNA-methylation and gene expression. Accordingly, we developed a bioinformatic tool to analyse differentially methylated regions and the TFs interacting with them. By overlaying our osteoblastogenesis differentially methylated regions with ENCODE TF ChIP-seq data we obtained a set of candidate TFs associated to DNA-methylation changes. Among them, ZEB1 TF was highly related with DNA-methylation. Using RNA interference, we confirmed that ZEB1, and ZEB2, played a key role in adipogenesis and osteoblastogenesis processes. For clinical relevance, ZEB1 mRNA expression in human bone samples was evaluated. This expression positively correlated with weight, body mass index, and PPARγ expression. CONCLUSIONS: In this work we describe an osteoblastogenesis-associated DNA-methylation profile and, using these data, validate a novel computational tool to identify key TFs associated to age-related disease processes. By means of this tool we identified and confirmed ZEB TFs as mediators involved in the MSCs differentiation to osteoblasts and adipocytes, and obesity-related bone adiposity.

Cisplatin-induced azoospermia and testicular damage ameliorated by adipose-derived mesenchymal stem cells

BACKGROUND: The testes are highly susceptible to the adverse effects of chemotherapy and radiation at all stages of life. Exposure to these threats mainly occurs during cancer treatment and as an occupational hazard in radiation centers. The present study investigated the regenerative ability of adipose-derived mesenchymal stem cells (ADMSCs) against the adverse effects of cisplatin on the structure and function of the testes. METHODS: New Zealand white rabbits (N = 15) were divided into three groups of five: a negative control group (no treatment), a cisplatin group (single dose of cisplatin into each testis followed three days later by a PBS injection), and a cisplatin + ADMSCs group (cisplatin injection followed three days later by an ADMSC injection). On day 45 post-treatment, serum testosterone levels were evaluated, and the testes and epididymis were collected for histology, oxidative stress examination, and epididymal sperm analysis. RESULTS: Cisplatin caused damage to the testicular tissue and decreased serum testosterone levels, epididymal sperm counts, and oxidants. An antioxidant imbalance was detected due to increasing malondialdehyde (MDA) and reduced glutathione (GSH) levels in testicular tissue. The ADMSC-treated group displayed a moderate epididymal sperm count, adequate antioxidant protection, suitable hormone levels, and enhanced testicular tissue morphology. CONCLUSIONS: ADMSCs treatment repaired damaged testicular tissue, enhanced biochemical parameters, and modified pathological changes caused by cisplatin.

Approaches in the treatment of perianal fistula in Crohn disease

Perianal fistula is a common complication of Crohn disease, and it is a great burden on the life and psychology of patients, but its treatment is still a difficult problem to face. In recent years, progress in the treatment of Crohn disease has progressed rapidly due to the advent of biological agents, but there has been a lack of research on perianal fistula in Crohn disease, and the direction of research has been scattered; therefore, the author reviews the traditional treatment of perianal fistula in Crohn disease in the context of the available literature and discusses emerging and potential therapeutic approaches. (AU)

Avaliação dos efeitos modulatórios da hematopoese no envelhecimento: Papel das células tronco mesenquimais medulares / Evaluation of the modulatory effects of hematopoiesis during aging: Role of bone marrow mesenchymal stem cells

O envelhecimento é um processo fisiológico que traz consigo uma série de alterações no organismo que se estendem até o nível molecular. Diante disto, este é um processo complexo que afeta diversos tecidos, sendo um deles o hematopoético, local onde, através de interações da Célula Tronco Hematopoética (CTH) com o ambiente ao seu redor, incluindo a Célula Tronco Mesenquimal (CTM), ocorre a hematopoese. Embora já sejam descritas na literatura algumas alterações na medula óssea consequentes do envelhecimento, os mecanismos por trás de tais mudanças permanecem elusivas, principalmente no âmbito das interações celulares ocorrentes na medula óssea. Portanto, este trabalho buscou investigar como o envelhecimento afeta a regulação hematopoética no contexto de sua relação com as CTM medulares. Para esta pesquisa, foram utilizados camundongos machos isogênicos da linhagem C57BL/6, dividindoos em grupos conforme sua idade: jovens (3 ­ 5 meses) e idosos (18 ­ 19 meses). Foi realizada a caracterização do modelo através de aspectos físicos como consumo proteico, variação de peso, entre outros, seguido de avaliação bioquímica e hematológica. Adicionalmente, foram coletadas células medulares e, posteriormente, realizado o isolamento das CTMs. Para estudar a relação destas células com a hematopoese, foram realizados ensaios in vitro utilizando a linhagem celular leucêmica C1498 (TIB-49™, ATCC®) mantidas em contato com o sobrenadante das CTMs isoladas. Quanto aos parâmetros bioquímicos, os animais idosos apresentaram menores níveis de albumina, aspartato alanina transferase (ALT) e de triglicerídeos quando comparados aos animais jovens. Contrariamente, os animais idosos apresentaram um maior nível de colesterol. Na avaliação hematológica, foi constatado pelo hemograma que os animais idosos apresentaram valores comparáveis aos animais jovens, todavia, o mielograma mostrou menor celularidade geral, seguido de menor número de células da linhagem eritroide e maior número de precursores granulocíticos. Através da imunofenotipagem, foi revelado um maior número de CTHs e de precursores grânulosmonocíticos na medula de animais idosos quando comparado aos jovens, e uma menor frequência de progenitores linfoides. Na imunofenotipagem de sangue periférico de animais idosos houve uma redução no número de linfócitos B e de eritrócitos, e aumento na população de células natural killers. Na imunofenotipagem de CTMs, o marcador CD73 apresentou menor expressão nos animais idosos. Avaliando o secretoma destas células estromais, foram encontrados no sobrenadante de CTMs de animais idosos aumentos significativos nas concentrações de CXCL12 e SCF e redução de IL-11. No âmbito molecular, as CTMs de animais idosos apresentaram aumento na expressão de Akt1, Nos e Ppar-γ, e redução na expressão de Csf3 e Cdh2. Adicionalmente, quando comparado a ação das CTMs de animais idosos em relação as CTMs de animais jovens, observou-se que CTMs de animais idosos foram capazes de aumentar a expressão de Sox2, Pou5f1 e Nanog e diminuir a expressão de Cdkn1a de células da linhagem C1498. O sobrenadante de CTMs de animais idosos também resultou na maior proliferação e migração de células da linhagem C1498. Portanto, levando em consideração a importância das CTMs sobre a regulação do sistema hematopoético, pode-se concluir que, no envelhecimento, as CTMs criam um ambiente propício para a proliferação celular no qual a manutenção da pluripotência é estimulada, o que pode acarretar em uma desregulação do sítio hematopoético quando habitado por células malignas

Aging is a physiological process in which occurs a series of alterations in an organism that extend to a molecular level. It is a complex process that affects various tissues, one of them being the bone marrow, wherethrough the interactions of the hematopoietic stem cell (CTH) with its surrounding environment, including with the mesenchymal stem cell (CTM), hematopoiesis takes place. Although some aging-associated alterations in the bone marrow can be found described in the literature, the mechanisms behind said changes remain elusive, especially when regarding the cellular interactions present inside the bone marrow. Therefore, this research aimed to investigate how aging affects the regulation of hematopoiesis in the context of its interactions with bone marrow-derived CTMs. For this investigation, male isogenic C57BL/6 mice were used as animal models. These were separated in two groups according to their age: young (3 ­ 5 months) and aged (18 ­ 19 months). The animal models were characterized by their physical properties such as protein intake and weight variation, followed by biochemical and hematological evaluation. Bone marrow cells were obtained and identified through immunophenotyping, thus isolating different cell populations, including the CTMs. To study the relationship between these cells and hematopoiesis, in vitro assays were conducted utilizing the leukemic cell lineage C1498 (TIB-49™, ATCC®) maintained in contact with the supernatant of isolated CTMs. By their biochemical profile, aged mice showed lower levels of albumin, alanine-aspartate transferase (ALT) and triglycerides compared to the young group. In contrast, aged mice had a higher cholesterol level. Hematological evaluation by total blood count showed similar results between the two groups, however, the myelogram revealed that the aged animals had lower cellularity, with less frequent cells from the erythroid lineage, with an increase in granulocytic precursors. Through immunophenotyping, it was also revealed that aged mice have higher numbers of hematopoietic stem cells, while also being noted a reduced population of lymphoid progenitors. An increase in the granulomonocytic progenitors was also found. Immunophenotyping peripheral blood cells of aged mice revealed reduced numbers of B lymphocytes and erythrocytes, and an increased natural killer cell population. Additionally, the cell surface marker CD73 was found to be less expressed in aged mice CTMs. The secretome of these stromal cells obtained from aged mice showed higher levels of CXCL12 and SCF, and lower levels of IL-11when compared to the young counterparts. At a molecular level, CTMs obtained from aged mice expressed more Akt1, Nos and Ppar-γ, while the expression of Csf3 and Cdh2 was reduced. Additionally, when comparing the effects of aged mice CTMs with young mice CTMs, it was observed that the first expressed were capable of increasing the expression of Sox2, Pou5f1 and Nanog, while decreasing Cdkn1a expression in the C1498 cell lineage. The supernatant obtained from aged mice also favored the proliferation and cell migration of the C1498 cell line. Thus, considering the importance that CTMs have over the hematopoietic system, we can conclude that, in aging, CTMs create a special environment which favors cell proliferation and maintenance of pluripotency, which can result in a dysregulation of the hematopoietic tissue when malignant cells are present

Accelerating Wound Healing of Traumatic Ulcer with Topical Application of Dental Pulp Mesenchymal Stem Cell Secretome and Robusta Green Coffee Bean Extract Combination in vivo

ABSTRACT Objective: To investigate the ability of a combination dental pulp mesenchymal stem cell secretome (DPMSCS), robusta green coffee bean extract (RGCBE), and Carboxymethylcellulose-Natrium (CMC-Na) in a Wistar rats model of traumatic ulcers. Material and Methods: Twenty-eight young, male, healthy Wistar rats (Rattus norvegicus) were divided into seven groups randomly: Group K0, group K1-3 (traumatic ulcer rats that received CMC-Na gel for three days), group K1-7 (traumatic ulcer rats that received CMC-Na gel for seven days), group K2-3 (traumatic ulcer rats that received RGCBE for three days), group K2-7 (traumatic ulcer rats that received RGCBE for seven days), group K3-3 (traumatic ulcer rats that received DPMSCS for three days), and group K3-7 (traumatic ulcer rats that received DPMSCS for seven days). An ulcer was made with an amalgam stopper on the right buccal mucosa of the rats. DPMSCS 50% gel was applied to the ulcer on the left buccal mucosa. The ulcer diameter was measured on day 3 and day 7. Results: There was a significant difference in the diameter of the ulcer, the number of neutrophils, and fibroblasts in the treatment group compared to the control group on day 7. Conclusion: A combination of DPMSCS and RGCBE 50% accelerates traumatic ulcer wound healing by lowering ulcer diameter, decreasing neutrophil counts, and increasing fibroblast proliferation in vivo.

Treatment of intrauterine adhesions in rats with hypoxia-cultured BMSC-derived exosomes / 中华妇产科杂志

Objective: To perform intrauterine adhesion modeling, and to investigate the repair effect of hypoxic treated bone marrow mesenchymal stem cells (BMSC) and their derived exosomes (BMSC-exo) on endometrial injury. Methods: BMSC and their exosomes BMSC-exo extracted from rats' femur were cultured under conventional oxygen condition (21%O2) or hypoxia condition (1%O2). Intrauterine adhesion modeling was performed on 40 healthy female SD rats by intrauterine injection of bacterial lipopolysaccharide after curettage. On the 28th day of modeling, 40 rat models were randomly divided into five groups, and interventions were performed: (1) NC group: 0.2 ml phosphate buffered solution was injected into each uterine cavity; (2) BMSC group: 0.2 ml BMSC (1×106/ml) with conventional oxygen culture was injected intrauterine; (3) L-BMSC group: 0.2 ml of hypoxic cultured BMSC (1×106/ml) was injected intrauterine; (4) BMSC-exo group: 0.2 ml of BMSC-exo cultured with conventional oxygen at a concentration of 500 μg/ml was injected into the uterine cavity; (5) L-BMSC-exo group: 0.2 ml hypoxic cultured BMSC-exo (500 μg/ml) was injected intrauterine. On the 14th and 28th day of treatment, four rats in each group were sacrificed by cervical dislocation after anesthesia, and endometrial tissues were collected. Then HE and Masson staining were used to observe and calculate the number of glands and fibrosis area in the endometrium. The expressions of angiogenesis related cytokines [vascular endothelial growth factor A (VEGFA) and CD31], and fibrosis-related proteins [collagen-Ⅰ, collagen-Ⅲ, smooth muscle actin α (α-SMA), and transforming growth factor β1 (TGF-β1)] in endometrial tissues were detected by western blot. Results: (1) HE and Masson staining showed that the number of endometrial glands in L-BMSC group, BMSC-exo group and L-BMSC-exo group increased and the fibrosis area decreased compared with NC group on the 14th and 28th day of treatment (all P<0.05). Noteworthily, the changes of L-BMSC-exo group were more significant than those of BMSC-exo group (all P<0.05), and the changes of BMSC-exo group were greater than those of BMSC group (all P<0.05). (2) Western blot analysis showed that, compared with NC group, the expressions of collagen-Ⅲ and TGF-β1 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group decreased on the 14th and 28th day of treatment (all P<0.05). As the treatment time went on, the expressions of fibrosis-related proteins were different. Compared with BMSC group, the expressions of collagen-Ⅲ, α-SMA and TGF-β1 in the BMSC-exo group and L-BMSC group decreased on the 28th day (all P<0.05). Moreover, the expressions of collagen-Ⅲ and TGF-β1 in L-BMSC-exo group were lower than those in BMSC-exo group on the 28th day (all P<0.05). And the expressions of collagen-Ⅰ, α-SMA and TGF-β1 in L-BMSC-exo group were lower than those in L-BMSC group on the 28th day (all P<0.05). (3) The results of western blot analysis of VEGFA and CD31 showed that, the expressions of VEGFA and CD31 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group increased on the 14th and 28th day of treatment compared with NC group (all P<0.05). Treatment for 28 days, the expressions of VEGFA and CD31 in BMSC-exo group and CD31 in L-BMSC group were higher than those in BMSC group (all P<0.05). Moreover, the expressions of VEGFA and CD31 in L-BMSC-exo group were higher than those in BMSC-exo group and L-BMSC group on the 28th day (all P<0.05). Conclusions: Treatment of BMSC and their exosomes BMSC-exo with hypoxia could promote endometrial gland hyperplasia, inhibit tissue fibrosis, and further repair the damaged endometrium in rats with intrauterine adhesion. Importantly, hypoxic treatment of BMSC-exo is the most effective in intrauterine adhesion rats.

Extracellular vesicle-carried GTF2I from mesenchymal stem cells promotes the expression of tumor-suppressive FAT1 and inhibits stemness maintenance in thyroid carcinoma / 医学前沿

Through bioinformatics predictions, we identified that GTF2I and FAT1 were downregulated in thyroid carcinoma (TC). Further, Pearson's correlation coefficient revealed a positive correlation between GTF2I expression and FAT1 expression. Therefore, we selected them for this present study, where the effects of bone marrow mesenchymal stem cell-derived EVs (BMSDs-EVs) enriched with GTF2I were evaluated on the epithelial-to-mesenchymal transition (EMT) and stemness maintenance in TC. The under-expression of GTF2I and FAT1 was validated in TC cell lines. Ectopically expressed GTF2I and FAT1 were found to augment malignant phenotypes of TC cells, EMT, and stemness maintenance. Mechanistic studies revealed that GTF2I bound to the promoter region of FAT1 and consequently upregulated its expression. MSC-EVs could shuttle GTF2I into TPC-1 cells, where GTF2I inhibited TC malignant phenotypes, EMT, and stemness maintenance by increasing the expression of FAT1 and facilitating the FAT1-mediated CDK4/FOXM1 downregulation. In vivo experiments confirmed that silencing of GTF2I accelerated tumor growth in nude mice. Taken together, our work suggests that GTF2I transferred by MSC-EVs confer antioncogenic effects through the FAT1/CDK4/FOXM1 axis and may be used as a promising biomarker for TC treatment.

Mesenchymal stem cell-derived apoptotic bodies alleviate alveolar bone destruction by regulating osteoclast differentiation and function / 国际口腔科学杂志·英文版

Periodontitis is caused by overactive osteoclast activity that results in the loss of periodontal supporting tissue and mesenchymal stem cells (MSCs) are essential for periodontal regeneration. However, the hypoxic periodontal microenvironment during periodontitis induces the apoptosis of MSCs. Apoptotic bodies (ABs) are the major product of apoptotic cells and have been attracting increased attention as potential mediators for periodontitis treatment, thus we investigated the effects of ABs derived from MSCs on periodontitis. MSCs were derived from bone marrows of mice and were cultured under hypoxic conditions for 72 h, after which ABs were isolated from the culture supernatant using a multi-filtration system. The results demonstrate that ABs derived from MSCs inhibited osteoclast differentiation and alveolar bone resorption. miRNA array analysis showed that miR-223-3p is highly enriched in those ABs and is critical for their therapeutic effects. Targetscan and luciferase activity results confirmed that Itgb1 is targeted by miR-223-3p, which interferes with the function of osteoclasts. Additionally, DC-STAMP is a key regulator that mediates membrane infusion. ABs and pre-osteoclasts expressed high levels of DC-STAMP on their membranes, which mediates the engulfment of ABs by pre-osteoclasts. ABs with knock-down of DC-STAMP failed to be engulfed by pre-osteoclasts. Collectively, MSC-derived ABs are targeted to be engulfed by pre-osteoclasts via DC-STAMP, which rescued alveolar bone loss by transferring miR-223-3p to osteoclasts, which in turn led to the attenuation of their differentiation and bone resorption. These results suggest that MSC-derived ABs are promising therapeutic agents for the treatment of periodontitis.