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.

MSC-derived exosomes protect auditory hair cells from neomycin-induced damage via autophagy regulation

BACKGROUND: Sensorineural hearing loss (SNHL) poses a major threat to both physical and mental health; however, there is still a lack of effective drugs to treat the disease. Recently, novel biological therapies, such as mesenchymal stem cells (MSCs) and their products, namely, exosomes, are showing promising therapeutic potential due to their low immunogenicity, few ethical concerns, and easy accessibility. Nevertheless, the precise mechanisms underlying the therapeutic effects of MSC-derived exosomes remain unclear. RESULTS: Exosomes derived from MSCs reduced hearing and hair cell loss caused by neomycin-induced damage in models in vivo and in vitro. In addition, MSC-derived exosomes modulated autophagy in hair cells to exert a protective effect. Mechanistically, exogenously administered exosomes were internalized by hair cells and subsequently upregulated endocytic gene expression and endosome formation, ultimately leading to autophagy activation. This increased autophagic activity promoted cell survival, decreased the mitochondrial oxidative stress level and the apoptosis rate in hair cells, and ameliorated neomycin-induced ototoxicity. CONCLUSIONS: In summary, our findings reveal the otoprotective capacity of exogenous exosome-mediated autophagy activation in hair cells in an endocytosis-dependent manner, suggesting possibilities for deafness treatment.

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.

Stability study of umbilical cord mesenchymal stem cells formulation in large-scale production / 药学学报

Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

Reconstruction of rat calvarial defects utilizing an ultraviolet-cured hydrogel loaded with bone marrow mesenchymal stem cells / 口腔疾病防治

Objective@#To investigate the osteogenic properties of a methacrylated gelatin (GelMA) / bone marrow mesenchymal stem cells (BMSCs) composite hydrogel applied to the skull defect area of rats and to provide an experimental basis for the development of bone regeneration biomaterials.@*Methods@#This study was approved by the Animal Ethics Committee of Nanjing University. A novel photocurable composite biohydrogel was developed by constructing photoinitiators [lthium phenyl (2,4,6-trimethylbenzoyl) phosphinate, LAP], GelMA, and BMSCs. The surface morphology and elemental composition of the gel were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The compressive strength of the gel was evaluated using an electronic universal testing machine. After in vitro culture for 1, 2, and 5 days, the proliferation of the BMSCs in the hydrogels was assessed using a CCK-8 assay, and their survival and morphology were examined through confocal microscopy. A 5 mm critical bone deficiency model was generated in a rat skull. The group receiving composite hydrogel treatment was referred to as the GelMA/BMSCs group, whereas the untreated group served as the control group. At the 4th and 8th weeks, micro-CT scans were taken to measure the bone defect area and new bone index, while at the 8th week, skull samples from the defect area were subjected to H&E staining, van Gieson staining, and Goldner staining to evaluate the quality of bone regeneration and new bone formation.@*Results@#SEM observed that the solidified GelMA showed a 3D spongy gel network with uniform morphology, the porosity of GelMA was 73.41% and the pore size of GelMA was (28.75 ± 7.13) μm. EDX results showed that C and O were evenly distributed in the network macroporous structure of hydrogel. The hydrogel compression strength was 152 kPa. On the 5th day of GelMA/BMSCs culture, the cellular morphology transitioned from oval to spindle shaped under microscopic observation, accompanied by a significant increase in cell proliferation (159.4%, as determined by the CCK-8 assay). At 4 weeks after surgery, a 3D reconstructed micro-CT image revealed a minimal reduction in bone defect size within the control group and abundant new bone formation in the GelMA/BMSCs group. At 8 weeks after surgery, no significant changes were observed in the control group's bone defect area, with only limited evidence of new bone growth; however, substantial healing of skull defects was evident in the GelMA/BMSCs group. Quantitative analysis at both the 4- and 8-week examinations indicated significant improvements in the new bone volume (BV), new bone volume/total bone volume (BV/TV), bone surface (BS), and bone surface/total bone volume (BS/TV) in the GelMA/BMSCs group compared to those in the control group (P<0.05). Histological staining showed continuous and dense formation of bone tissue within the defects in the GelMA/BMSCs group and only sporadic formation of new bone, primarily consisting of fibrous connective tissue, at the defect edge in the control group.@*Conclusion@#Photocuring hydrogel-based stem cell therapy exhibits favorable biosafety profiles and has potential for clinical application by inducing new bone formation and promoting maturation within rat skull defects.

Research progress on molecular mechanism of traditional chinese medicine active ingredients interfering bone marrow mesenchymal stem cells senescence / 中国临床药理学与治疗学

The senescence of bone marrow mesenchymal stem cells (BM-MSCs) will induce age-related bone tissue degeneration and chronic inflammation, and reduce its application effect for cell therapy. More and more active ingredients of traditional chinese medicine have been proved to intervene BM - MSCs senescence, playing an important role in bone diseases prevention and treatment, and improving the therapeutic effect of BM-MSCs. In this paper, the latest research progress on the molecular mechanism of traditional chinese medicine active ingredients interfering BM-MSCs senescence was summarized, in order to provide new direction and reference basis for senescence intervention research and clinical application improvement of BM-MSCs.

Advances in the study of mesenchymal stem cells in obstructive sleep apnea hypoventilation syndrome / 中国临床药理学与治疗学

Mesenchymal stem cells (MSCs) are self-regenerating, rapidly proliferating pluripotent stem cells that depend primarily on their derived pro-angiogenic, inflammatory regulatory, and trophic factors to exert beneficial effects that attenuate deleterious inflammatory responses, reduce vascular damage, and promote tissue repair and regeneration. Obstructive sleep apnea hypoventilation syndrome (OSAHS) is a chronic disorder marked by oropharyngeal collapse during sleep, resulting in transient reduced airflow, large fluctuations in intrathoracic pressure, and intermittent hypoxia and hypercapnia. OSAHS subsequently cytokine-mediated inflammatory cascades, oxidative stress, and ischemia, recruit MSCs from inflamed and damaged tissues through MSCs-derived of anti-inflammatory and pro-angiogenic factor activity, reduce hypoxia, suppress inflammation, promote regeneration, and prevent fibrosis in OSAHS-injured tissues. In this paper, we will describe the pathogenesis of inflammation, oxidative stress, fibrosis and ischemia from the perspective of OSAHS, highlighting the current research progress on MSCs-dependent regulation of OSAHS-related pathology.

Progress in the potential therapeutic mechanism of mesenchymal stem cell-derived exosomes for liver fibrosis / 中国临床药理学与治疗学

Liver fibrosis is pathological in most chronic liver diseases. Exosomes secreted by mesenchymal stem cells (MSCs) can regulate liver fibrosis through mechanisms such as inhibition of inflammatory response and proliferation of activated hepatic stellate cells, regulation of immune cells and metabolism. Therefore, MSC-derived exosomes can be used as a cell-free therapy for chronic liver disease, expanding new ideas for the treatment of chronic liver disease. Recent researches on MSC-derived exosomes in the treatment of liver fibrosis are reviewed in this article.

Effect of miR-141-5p/ZNF705A on adhesion of bone marrow mesenchymal stem cells in chronic myeloid leukemia cell-derived exosomes / 中国药理学通报

Aim To investigate the effect of miR-141-5p/ZNF705A in chronic myeloid leukemia(CML)cell-derived exosome(Exo)on the adhesion of bone marrow mesenchymal stem cells(BMSCs). Methods The morphology and size of Exo in peripheral blood from CML patients and K562 cells were examined by electron microscopy and NTA particle size analysis. The expressions of Exo and BMSCs marker molecules and adhesion proteins in K562 cells were detected by qRT-PCR and Western blot before and after transfection. The adhesion ability of BMSCs was detected by cell adhesion assay, and the cellular activity of BMSCs was examined using CCK-8. miR-141-5p binding to ZNF705A was detected by luciferase assay. Results qRT-PCR results showed that miR-141-5p expression was significantly reduced in both CML patients and K562 cell-derived Exo. qRT-PCR, Western blot and other results showed that BMSCs in CML patients had significantly reduced the expression of adhesion proteins CD44 and CXCL12, and were able to phagocytose K562 cell-derived Exo. Further, K562-derived Exo was found to reduce CD44 and CXCL12 expression and adhesion in Exo-promoted BMSCs compared with CD34+ cells. Meanwhile, the results of dual luciferase reporter assay verified that miR-141-5p targeted binding to ZNF705A. Finally, we found ZNF705A could be targeted by up-regulating miR-141-5p expression in Exo of K562 cells, which in turn inhibited the adhesion of BMSCs. Conclusions K562 cells down-regulate miR-141-5p expression in Exo and inhibit the adhesion function of BMSCs by targeting ZNF705A, thus regulating the bone marrow hematopoietic function in CML patients.

Role of mesenchymal stem cells and their exosomes in the treatment of drug-induced liver injury / 临床肝胆病杂志

The incidence rate of drug-induced liver injury （DILI） is increasing year by year with unknown mechanisms， and the treatment methods for DILI mainly include drugs， liver support systems， and liver transplantation， all of which have certain limitations. Therefore， the search for safer and more effective treatment methods has become a research hotspot at present. Studies have shown that mesenchymal stem cells and their exosomes can alleviate liver injury by reducing liver inflammation， promoting hepatocyte proliferation and regeneration， inhibiting the apoptosis of hepatocytes， improving oxidative stress， and regulating immunity. This article briefly reviews the role of mesenchymal stem cells and their exosomes in the treatment of DILI， so as to provide a reference for further research.

Effect of human umbilical cord mesenchymal stem cells in treatment of mice with liver fibrosis and its mechanism / 临床肝胆病杂志

ObjectiveTo investigate the effect of human umbilical cord mesenchymal stem cells （hUCMSCs） in the treatment of mice with liver fibrosis and its mechanism. MethodsA total of 18 specific pathogen-free C57BL/6 mice， aged 6 weeks， were selected and divided into control group （n=6）， carbon tetrachloride （CCl4） model group （CCl4 group， n=6）， and hUCMSCs treatment group （MSC group， n=6） using a random number table. The mice in the CCl4 group and the MSC group were given intraperitoneal injection of CCl4 solution to establish a mouse model of liver fibrosis， while those in the control group were injected with the same dose of corn oil， and the mice in the MSC group were injected with hUCMSCs via the caudal vein during the injection of CCl4. At the end of week 8， mouse serum was collected， and the mice were sacrificed to collect and fix the liver. Enzyme-linked immunosorbent assay was used to measure the levels of inflammatory factors； an automatic biochemical detector was used to measure liver function parameters； HE staining， Masson staining， Sirius Red staining， and α-SMA immunofluorescence assay were used to evaluate liver fibrosis. Hepatic stellate cells （HSCs） stimulated by TGF-β were co-cultured with hUCMSCs in the medium with or without chitinase-3 like-protein-1 （CHI3L1）， and Western blot was used to measure the expression levels of proteins. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the Dunnett’s t-test was used for further comparison between two groups. ResultsMasson staining and Sirius Red staining showed that the CCl4 group had a significantly higher degree of fibrosis than the control group （both P<0.05）， and the MSC group had significant alleviation of fibrosis compared with the CCl4 group （both P<0.05）. Compared with the control group， the CCl4 group had significant increases in the levels of interleukin-1β， interleukin-6 （IL-6）， aspartate aminotransferase （AST）， alanine aminotransferase （ALT）， and alkaline phosphatase （ALP） （all P<0.05）， and compared with the CCl4 group， the MSC group had significant reductions in the levels of IL-6， AST， ALT， and ALP （all P<0.05）. The CCl4 group had significantly higher expression levels of CHI3L1 and α-SMA than the control group and the MSC group （all P<0.05）. The cell culture experiment showed that the MSC+HSC group had a significantly higher expression level of Bax than the HSC group and the MSC+CHI3L1 group （both P<0.05）， suggesting that CHI3L1 reversed the pro-apoptotic effect of MSC on activated HSCs. ConclusionThis study shows that hUCMSCs can improve liver fibrosis in mice， possibly by inhibiting CHI3L1 to promote the apoptosis of HSCs.

BMSCs promote M2 macrophage polarization to attenuate acute radiation-induced lung injury / 中国辐射卫生

Objective To investigate the therapeutic effects of bone marrow mesenchymal stem cells (BMSCs) for radiation-induced lung injury (RILI) and the underlying mechanism. Methods Forty-five healthy adult male C57BL/6 mice were randomly divided into control, model, and BMSCs groups. The model and BMSCs groups received a single irradiation dose of 20 Gy to the chest, while the control group did not receive X-ray irradiation. For the BMSCs group, an injection of 1 × 106 BMSCs cells was administered via the tail vein within 6 h after irradiation. In the 5th week, the lung tissue was taken to observe pathological changes with HE staining; examine the expression of the inflammatory factors interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) with immunohistochemical staining; observe the polarization of macrophages with immunofluorescence staining; and measure the expression of the epithelial-mesenchymal transition markers E-cadherin, N-cadherin, and vimentin proteins by Western blot. Results After radiation, the model group developed pulmonary vasodilation and congestion with septal thickening and inflammatory cell infiltration, and these changes were markedly reduced in the BMSCs group. The model group showed significantly down-regulated expression of IL-6 and TNF-α compared with significantly increased levels in the model group (P < 0.01, P < 0.05). Treatment with BMSCs significantly increased the polarization of lung macrophages towards the M2 type, while significantly decreasing the abnormally increased N-cadherin and vimentin levels in RILI mice (P < 0.05, P < 0.01). Conclusion BMSCs have therapeutic effects for RILI mice, which may be through promoting macrophage polarization from M1 to M2.

Application progress of mesenchymal stem cells in islet transplantation for type 1 diabetes mellitus / 器官移植

Islet transplantation is considered as one of the most effective approach for type 1 diabetes mellitus, although its efficacy is limited by several factors. Anoxia, stress and rejection occurring during the isolation, culturing and transplantation of islets may have impact on the outcome of the islet transplantation. Due to the biological properties such as anti-inflammation, angiogenetic promotion and immune regulation, mesenchymal stem cells (MSCs) are all the way focused by researchers. Additionally, exosome, a derivative of MSC, also plays an import role in regulating anoxia-induced oxidative stress modulation, angiogenetic promotion, and immune regulation. MSC-based islet transplantation may be a useful therapeutic tool in treating type 1 diabetes. Therefore, in this review, the potential effect of MSC prior and posterior to the operation of the islet transplantation, its clinical application as well as its limitations were reviewed, aiming to offer insights into the future application of islet transplantation in treating type 1 diabetes.

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.

Isolation of bone marrow mesenchymal stem cells in transgenic pigs and co-culture with porcine islets / 器官移植

Objective To investigate the isolation and culture of porcine bone marrow mesenchymal stem cell (BMSC) with α-1, 3-galactosyltransferase (GGTA1) gene knockout (GTKO), GTKO/ human CD46 (hCD46) insertion and cytidine monopho-N-acetylneuraminic acid hydroxylase (CMAH)/GGTA1 gene knockout (Neu5GC/Gal), and the protective effect of co-culture with porcine islets on islet cells. Methods Bone marrow was extracted from different transgenic pigs modified with GTKO, GTKO/hCD46 and Neu5GC/Gal. Porcine BMSC were isolated by the whole bone marrow adherent method and then cultured. The morphology of BMSC was observed and the surface markers of BMSC were identified by flow cytometry. Meantime, the multi-directional differentiation induced by BMSC was observed, and the labeling and tracing of BMSC were realized by green fluorescent protein (GFP) transfection. The porcine BMSC transfected with GFP were co-cultured with porcine islet cells. Morphological changes of porcine islet cells were observed, and compared with those in the porcine islet cell alone culture group. Results BMSC derived from pigs were spindle-shaped in vitro, expressing biomarkers of CD29, CD44, CD73, CD90, CD105 and CD166 rather than CD34 and CD45. These cells were able to differentiate into adipocytes, osteoblasts and chondrocytes. Porcine BMSC with GFP transfection could be labeled and traced, which could be stably expressed in the daughter cells after cell division. Porcine BMSC exerted certain protective effect on islet cells. Conclusions GFP-labeled porcine BMSC modified with GTKO, GTKO/hCD46 and Neu5GC/Gal are successfully established, which exert certain protective effect upon islet cells.

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.

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.