BackgroundCorneal stromal cells (CSCs) are components of the corneal endothelial microenvironment that can be induced to form a functional tissue-engineered corneal endothelium. Adipose-derived mesenchymal stem cells (ADSCs) have been reported as an important component of regenerative medicine and cell therapy for corneal stromal damage. We have demonstrated that the treatment with ADSCs leads to phenotypic changes in CSCs in vitro. However, the underlying mechanisms of such ADSC-induced changes in CSCs remain unclear.

MethodsADSCs and CSCs were isolated from New Zealand white rabbits and cultured in vitro. An Exosome Isolation Kit, Western blotting, and nanoparticle tracking analysis (NTA) were used to isolate and confirm the exosomes from ADSC culture medium. Meanwhile, the optimal exosome concentration and treatment time were selected. Cell Counting Kit-8 and annexin V-fluorescein isothiocyanate/propidium iodide assays were used to assess the effect of ADSC- derived exosomes on the proliferation and apoptosis of CSCs. To evaluate the effects of ADSC- derived exosomes on CSC invasion activity, Western blotting was used to detect the expression of matrix metalloproteinases (MMPs) and collagens.

Results:ADSCs and CSCs were successfully isolated from New Zealand rabbits. The optimal concentration and treatment time of exosomes for the following study were 100 μg/ml and 96 h, respectively. NTA revealed that the ADSC-derived exosomes appeared as nanoparticles (40-200 nm), and Western blotting confirmed positive expression of CD9, CD81, flotillin-1, and HSP70 versus ADSC cytoplasmic proteins (all P < 0.01). ADSC-derived exosomes (50 μg/ml and 100 μg/ml) significantly promoted proliferation and inhibited apoptosis (mainly early apoptosis) of CSCs versus non-exosome-treated CSCs (all P < 0.05). Interestingly, MMPs were downregulated and extracellular matrix (ECM)-related proteins including collagens and fibronectin were upregulated in the exosome-treated CSCs versus non-exosome-treated CSCs (MMP1: t = 80.103, P < 0.01; MMP2: t = 114.778, P < 0.01; MMP3: t = 56.208, P < 0.01; and MMP9: t = 60.617, P < 0.01; collagen I: t = -82.742, P < 0.01; collagen II: t = -72.818, P < 0.01; collagen III: t = -104.452, P < 0.01; collagen IV: t = -133.426, P < 0.01, and collagen V: t = -294.019, P < 0.01; and fibronectin: t = -92.491, P < 0.01, respectively).

Conclusion:The findings indicate that ADSCs might play an important role in CSC viability regulation and ECM remodeling, partially through the secretion of exosomes.

Adipose Tissue ; cytology ; Animals ; Cell Proliferation ; physiology ; Cell Survival ; physiology ; Cells, Cultured ; Exosomes ; metabolism ; Extracellular Matrix ; metabolism ; Fibroblasts ; cytology ; metabolism ; Matrix Metalloproteinases ; metabolism ; Mesenchymal Stromal Cells ; cytology ; metabolism ; Rabbits

PURPOSE: Angiopoietin-1 (Ang1) is a critical factor for vascular stabilization and endothelial survival via inhibition of endothelial permeability and leukocyte- endothelium interactions. Hence, we hypothesized that treatment with umbilical cord mesenchymal stem cells (UCMSCs) carrying the Ang1 gene (UCMSCs-Ang1) might be a potential approach for acute lung injury (ALI) induced by lipopolysaccharide (LPS). MATERIALS AND METHODS: UCMSCs with or without transfection with the human Ang1 gene were delivered intravenously into rats one hour after intra-abdominal instillation of LPS to induce ALI. After the rats were sacrificed at 6 hours, 24 hours, 48 hours, 8 days, and 15 days post-injection of LPS, the serum, the lung tissues, and bronchoalveolar lavage fluid (BALF) were harvested for analysis, respectively. RESULTS: Administration of fluorescence microscope confirmed the increased presence of UCMSCs in the injured lungs. The evaluation of UCMSCs and UCMSCs-Ang1 actions revealed that Ang1 overexpression further decreased the levels of the pro-inflammatory cytokines TNF-α, TGF-β1, and IL-6 and increased the expression of the anti-inflammatory cytokine IL-10 in the injured lungs. This synergy caused a substantial decrease in lung airspace inflammation and vascular leakage, characterized by significant reductions in wet/dry ratio, differential neutrophil counts, myeloperoxidase activity, and BALF. The rats treated by UCMSCs-Ang1 showed improved survival and lower ALI scores. CONCLUSION: UCMSCs-Ang1 could improve both systemic inflammation and alveolar permeability in ALI. UC-derived MSCs-based Ang1 gene therapy may be developed as a potential novel strategy for the treatment of ALI.
Acute Lung Injury/chemically induced/*therapy ; Angiopoietin-1/*genetics ; Animals ; Bronchoalveolar Lavage Fluid ; Cytokines/metabolism ; Endotoxins ; Genetic Therapy ; Interleukin-10/metabolism ; Interleukin-6/metabolism ; Leukocyte Count ; Lipopolysaccharides ; Lung/metabolism ; Male ; *Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells/metabolism ; Neutrophils/metabolism ; Rats ; Transforming Growth Factor beta1/metabolism ; Tumor Necrosis Factor-alpha/metabolism ; Umbilical Cord/*cytology

OBJECTIVETo investigate the effect of human umbilical cord-derived mesenchymal stem cells (UC-MSC) on the differentiation of leukemic cells.

METHODSThe co-culture system of UC-MSC with acute promyelocytic leukemic cell line NB4 cells was constructed in vitro,and the differentiation status of the leukemic cells was assessed by cell morphology,nitroblue tetrazolium reduction test,and cell surface differentiation marker CD11b.

RESULTSUC-MSC induced the granulocytic differentiation of NB4 cells. When UC-MSC and a small dose of all-trans retinoic acid were applied together,the differentiation-inducing effect was enhanced in an additive manner. Interleukin (IL)-6Ra neutralization attenuated differentiation and exogenous IL-6-induced differentiation of leukemic cells.

CONCLUSIONUC-MSC can promotd granulocytic differentiation of acute promyelocytic leukemia cells by way of IL-6 and presented additive effect when combined with a small dose of all-trans retinoic acid.

Cell Differentiation ; Cell Line, Tumor ; Humans ; Interleukin-6 ; metabolism ; Leukemia, Promyelocytic, Acute ; pathology ; Mesenchymal Stromal Cells ; metabolism ; Tretinoin ; pharmacology ; Umbilical Cord ; cytology

OBJECTIVETo explore the effect of total flavonoids of Herba Epimedium (FHE) on BMP-2/RunX2/OSX signaling pathway in promoting osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs).

METHODSPassage 3 BMSCs were randomly divided into the control group, the experimental group, and the inhibitor group. BMSCs in the control group were cultured in 0.2% dimethyl sulfoxide + Osteogenuxic Supplement (OS) fluid + DMEM/F12 culture media. BMSCs in the experimental group were intervened by 20 microg/mL FHE. BMSCs in the inhibitor group were intervened by 20 microg/mL FHE and 1 microg/mL NOGGIN recombinant protein. At day 9 alkaline phosphatase (ALP) activity was measured. Calcium nodules were stained by alizarin red staining and the density was observed. The transcription expression of osteogenic differentiation-related proteins (type I collagen, osteocalcin, and osteopontin) and related factors of BMP-2/RunX2/OSX signaling pathway was assayed by RT-PCR.

RESULTSCompared with the control group, ALP activities were enhanced and the density of calcium nodules significantly increased; type I collagen, osteocalcin, and osteopontin expression levels were increased in the experimental group. The expression of osteogenesis-related transcription factor was also increased in the experimental group. Noggin recombinant protein inhibited FHE promoting BMSCs osteogenesis in the inhibitor group. Compared with the experimental group, ALP activity decreased (P < 0.05), the density of calcium nodules was lowered, expression levels of type I collagen, osteocalcin, osteopontin significantly decreased (P < 0.05) in the inhibitor group.

CONCLUSION20 microg/mL FHE promoted osteogenic differentiation process of BMSCs by BMP-2/RunX2/OSX signaling pathway.

Bone Morphogenetic Protein 2 ; metabolism ; Cell Differentiation ; drug effects ; Cells, Cultured ; Collagen Type I ; metabolism ; Core Binding Factor Alpha 1 Subunit ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Epimedium ; chemistry ; Flavonoids ; pharmacology ; Humans ; Mesenchymal Stromal Cells ; cytology ; drug effects ; Osteocalcin ; metabolism ; Osteogenesis ; drug effects ; Osteopontin ; metabolism ; Signal Transduction ; Sp7 Transcription Factor ; Transcription Factors ; metabolism

OBJECTIVEWe explored the expressions of the Notch and Wnt signaling pathways and their significance in the repair process of alveolar bone defects by establishing animal models with a composite of autologous bone marrow mesenchymal stem cells (BMSCs) and platelet-rich fibrin (PRF) to repair bone defects in the extraction sockets of rabbits.

METHODSA total of 36 two-month-old male New Zealand white rabbits were randomly divided into four groups, and the left mandibular incisors of all the rabbits were subjected to minimally invasive removalunder general anesthesia. BMSC-PRF compounds, single PRF, and single BMSC were implanted in Groups A, B, and C. No material was implanted in Group D (blank control). The animals were sacrificed at 4, 8 and 12 weeks after surgery, the bone defect was immediately drawn, and the bone specimens underwent surgery after four, eight, and twelve weeks, with three rabbits per time point. The expressions of Notch1 and Wnt3a in the repair process of the bone defect were measured via immunohistochemical and immunofluorescence detection.

RESULTSImmunohistochemistry showed that the expressions of Notch1 and Wnt3a in Groups A, B, and C were higher than that in Group D at the fourth and eighth week after operation (P<0.05). By contrast, the expressions of Notch1 and Wnt3a in Group D were higher than those in Groups A, B, and C at the twelfth week (P<0.05). Immunofluorescence showed that the expressions of both Notch1 and Wnt3a reached their peaks in the new bone cells of the bone defect after four weeks following surgery and gradually disappeared when the bone was repaired completely.

CONCLUSIONNotch1 and Wnt3a signaling molecules are expressed in the process of repairing bone defects using BMSC-PRF composites and can accelerate the healing by regulating the proliferation and differentiation of BMSCs. Moreover, the expressions of Notch and Wnt are similar, and a crosstalk between them may exist it.

Alveolar Bone Grafting ; methods ; Animals ; Blood Platelets ; Bone Marrow Cells ; cytology ; Bone Transplantation ; methods ; Bone and Bones ; abnormalities ; Cell Differentiation ; Fibrin ; administration & dosage ; Male ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stromal Cells ; Platelet-Rich Plasma ; Rabbits ; Random Allocation ; Receptor, Notch1 ; metabolism ; Tissue Engineering ; Wnt Signaling Pathway ; Wnt3A Protein ; metabolism ; Wound Healing

BACKGROUNDThe functional improvement following bone marrow stromal cells (BMSCs) transplantation after stroke is directly related to the number of engrafted cells and neurogenesis in the injured brain. Here, we tried to evaluate whether 3-methyl-1-phenyl-2-pyrazolin-5-one (MCI-186), a free radical scavenger, might influence BMSCs migration to ischemic brain, which could promote neurogenesis and thereby enhance treatment effects after stroke.

METHODSRat transient middle cerebral artery occlusion (MCAO) model was established. Two separate MCAO groups were administered with either MCI-186 or phosphate-buffered saline (PBS) solution to evaluate the expression of stromal cell-derived factor-1 (SDF-1) in ischemic brain, and compared to that in sham group (n = 5/ group/time point[at 1, 3, and 7 days after operation]). The content of chemokine receptor-4 (CXCR4, a main receptor of SDF-1) at 7 days after operation was also observed on cultured BMSCs. Another four MCAO groups were intravenously administered with either PBS, MCI-186, BMSCs (2 × 106), or a combination of MCI-186 and BMSCs (n = 10/group). 5-bromo-2-deoxyuridine (BrdU) and Nestin double-immunofluorescence staining was performed to identify the engrafted BMSCs and neuronal differentiation. Adhesive-removal test and foot-fault evaluation were used to test the neurological outcome.

RESULTSMCI-186 upregulated the expression of SDF-1 in ischemic brain and CXCR4 content in BMSCs was enhanced after hypoxic stimulation. When MCAO rats were treated with either MCI-186, BMSCs, or a combination of MCI-186 and BMSCs, the neurologic function was obviously recovered as compared to PBS control group (P < 0.01 or 0.05, respectively). Combination therapy represented a further restoration, increased the number of BMSCs and Nestin+ cells in ischemic brain as compared with BMSCs monotherapy (P < 0.01). The number of engrafted-BMSCs was correlated with the density of neuronal cells in ischemic brain (r = 0.72 , P < 0.01) and the improvement of foot-fault (r = 0.70, P < 0.01).

CONCLUSIONMCI-186 might promote BMSCs migration to the ischemic brain, amplify the neurogenesis, and improve the effects of cell therapy.

Animals ; Antipyrine ; analogs & derivatives ; therapeutic use ; Bone Marrow Cells ; cytology ; physiology ; Brain Ischemia ; drug therapy ; metabolism ; therapy ; Chemokine CXCL12 ; metabolism ; Disease Models, Animal ; Infarction, Middle Cerebral Artery ; drug therapy ; metabolism ; therapy ; Male ; Mesenchymal Stromal Cells ; physiology ; Neurogenesis ; physiology ; Rats ; Rats, Sprague-Dawley ; Stroke ; drug therapy ; metabolism ; therapy

BACKGROUNDMesenchymal stem cells (MSCs) are bone marrow stem cells which play an important role in tissue repair. The treatment with MSCs will be likely to aggravate the degree of fibrosis. The Wnt/β-catenin signaling pathway is involved in developmental and physiological processes, such as fibrosis. Dickkopfs (DKKs) are considered as an antagonist to block Wnt/β-catenin signaling pathway by binding the receptor of receptor-related protein (LRP5/6). DKK1 was chosen in attempt to inhibit fibrosis of MSCs by lowering activity of Wnt/β-catenin signaling pathway.

METHODSStable MSCs were randomly divided into four groups: MSCs control, MSCs + transforming growth factor-β (TGF-β), MSCs + DKK1, and MSCs + TGF-β + DKK1. Flow cytometry was used to identify MSCs. Cell viability was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide test. Immunofluorescence was used to detect protein expression in the Wnt/β-catenin signaling pathways. Western blotting analysis was employed to test expression of fibroblast surface markers and, finally, real-time reverse transcription polymerase chain reaction was employed to test mRNA expression of fibroblast surface markers and Wnt/β-catenin signaling proteins.

RESULTSCultivated MSCs were found to conform to the characteristics of standard MSCs: expression of cluster of differentiation (CD) 73, 90, and 105, not expression of 34, 45, and 79. We found that DKK1 could maintain the normal cell morphology of MSCs. Western blotting analysis showed that fibroblast surface markers were expressed in high quantities in the group MSCs + TGF-β. However, the expression was lower in the MSCs + TGF-β + DKK1. Immunofluorescence showed high expression of all Wnt/β-catnin molecules in the MSCs + TGF-β group but expressed in lower quantities in MSCs + TGF-β + DKK1 group. Finally, mRNA expression of fibroblast markers vimentin, α-smooth muscle actin and Wnt/β-catenin signaling proteins β-catenin, T-cell factor, and glycogen synthase kinase-3β was significantly increased in MSCs + TGF-β group compared to control (P < 0.05). Expression of the same fibroblast markers and Wnt/β-catenin was decreased to regular quantities in the MSCs + TGF-β + DKK1 group.

CONCLUSIONSDKK1, Wnt/β-catenin inhibitors, blocks the Wnt/β-catenin signaling pathway to inhibit the process of MSCs fibrosis. It might provide some new ways for clinical treatment of certain diseases.

Animals ; Cell Differentiation ; physiology ; Cells, Cultured ; Female ; Fibroblasts ; cytology ; metabolism ; Intercellular Signaling Peptides and Proteins ; genetics ; metabolism ; Mesenchymal Stromal Cells ; cytology ; metabolism ; Mice ; Rats ; Transforming Growth Factor beta ; genetics ; metabolism

Mesothelial cells (MCs) cover the surface of visceral organs and the parietal walls of cavities, and they synthesize lubricating fluids to create a slippery surface that facilitates movement between organs without friction. Recent studies have indicated that MCs play active roles in liver development, fibrosis, and regeneration. During liver development, the mesoderm produces MCs that form a single epithelial layer of the mesothelium. MCs exhibit an intermediate phenotype between epithelial cells and mesenchymal cells. Lineage tracing studies have indicated that during liver development, MCs act as mesenchymal progenitor cells that produce hepatic stellate cells, fibroblasts around blood vessels, and smooth muscle cells. Upon liver injury, MCs migrate inward from the liver surface and produce hepatic stellate cells or myofibroblast depending on the etiology, suggesting that MCs are the source of myofibroblasts in capsular fibrosis. Similar to the activation of hepatic stellate cells, transforming growth factor β induces the conversion of MCs into myofibroblasts. Further elucidation of the biological and molecular changes involved in MC activation and fibrogenesis will contribute to the development of novel approaches for the prevention and therapy of liver fibrosis.
Epithelial Cells/*physiology ; Epithelium/metabolism ; Hepatic Stellate Cells/*physiology ; Humans ; Liver/*cytology/injuries/*physiology ; Liver Cirrhosis/etiology/prevention & control ; Liver Regeneration/*physiology ; Mesenchymal Stromal Cells/physiology ; Myofibroblasts/physiology

OBJECTIVETo explore the effect of MicroRNA-146a (miR-146a) on the ability of BM-MSC to differentiate into adipocytes and osteoblasts.

METHODSBM-MSC were isolated from the bone marrow of healthy donors. The differentiation of BM-MSC into adipocytes and osteoblasts cells were done in vitro. After transfection with miR-146a inhibitor or mimics, the expression of miR-146a in BM-MSC was detected by real time quantitative PCR. The effect of MicroRNA-146a on the differentiation potential of BM-MSC was evaluated after transfection.

RESULTSBM-MSC possessed the ability to differentiate into adipocytes and osteoblasts cells when cultured in the induction medium. The expression of miR-146a was correspondingly down-regulated and up-regulated in BM-MSC after transfection. Compared with the control group, the expression of miR-146a was down-regulated (P < 0.01) after transfection with miR-146a inhibitor, while after transfection with miR-146a mimics it was significantly up-regulated. This study proved that the transfection with miR-146a inhibitor can inhibit BM-MSC differentiate into adipocytes (P < 0.01), while transfection with miR-146a mimics can promote differentiation of BM-MSC into adipocytes (P < 0.01). No effect of miR-146a inhibitor or miR-146a mimics on osteogenic differentiation of BM-MSC was observed (P > 0.05).

CONCLUSIONBM-MSC possess the ability to differentiate into adipocytes and osteoblasts. The miR-146a can promote BM-MSC to differentiate into adipocytes.

Adipocytes ; cytology ; Bone Marrow Cells ; cytology ; Cell Differentiation ; Cells, Cultured ; Humans ; Mesenchymal Stromal Cells ; cytology ; MicroRNAs ; metabolism ; Osteoblasts ; cytology ; Osteogenesis ; Transfection

OBJECTIVETo study the regulation of SIRT1 by transcription factor SREBP-1 in adipogeneic differentiation of bone marrow mesenchymal stem cells (BMMSC).

METHODSOil red O staining was used to identify the adipogenic differentiation of BMMSC; the mRNA transcription levels of AP2, LPL, SREBF-1, SIRT1 gene were detected by RT-PCR; the expession level of SREBP-1 was determined by Western-blot. The chromatin immunoprecipitation (ChIP) assay was used to investigate the binding of SREBP-1 to SIRT1 promoter.

RESULTSBMMSC exposed to adipogenesis inducing medium become mature adipocytes at day 14; the mRNA transcription levels of AP2, LPL, SREBF-1, SIRT1 genes were up-regulated in adipocyte differentiation of BMMSC; the protein level of SREBP-1 was higher obviously; SIRT1 gene sequences was succesfully amplified from the genomic DNA immunoprecipitated by SREBP-1 antibody.

CONCLUSIONSREBP-1 can bind to the promoter region of the SIRT1 gene in adipogenesis of BMMSC, and may be involved in the transcriptional regulation of the SIRT1 gene.

Adipocytes ; cytology ; Adipogenesis ; Cell Differentiation ; Cells, Cultured ; Chromatin Immunoprecipitation ; Gene Expression Regulation ; Humans ; Mesenchymal Stromal Cells ; cytology ; Promoter Regions, Genetic ; Sirtuin 1 ; metabolism ; Sterol Regulatory Element Binding Protein 1 ; metabolism ; Up-Regulation