Bone Mesenchymal Stem Cells Group Research Articles

The repair and regeneration mechanism of platelet-rich fibrin-promoting tissue after alveolar bone defect through the notch pathway.

This work investigated the effects of platelet-rich fibrin (PRF) combined with bone mesenchymal stem cells (BMSCs) on the repair of alveolar bone defect (ABD) and the related mechanism of the Notch1/Wnt3a signaling pathway. 28 healthy male New Zealand white rabbits were selected to prepare the BMSCs and PRF. Rabbits were rolled into a combination group (implanted with PRF + BMSCs for treatment), a PRF group (treated with PRF) a BMSC group (BMSCs for treatment), and a control group (Ctrl group, no material implantation), with 7 rabbits in each. The Notch1, Wnt3a, bone morphogenetic protein 9 (BMP9), and p-JNK in rabbits in various groups were compared. It was found that Notch1 and Wnt3a in the combination group were sharply higher than those in the PRF and BMSC groups at postoperative 5 and 10 weeks, exhibiting great differences (P<0.05). The osteocalcin (OCN) and alkaline phosphatase (ALP) in the combination group were higher based on those in the PRF group, BMSC group, and Ctrl group (all P<0.05). Meanwhile, BMP9 and P-JNK proteins in the combination group were much higher than those in the PRF, BMSC, and Ctrl groups, presenting obvious differences (P<0.05). The results revealed that PRF + BMSCs could more effectively downregulate the Notch1 and Wnt3a and activate the Notch1/Wnt3a signaling pathway, thus promoting the osteogenesis of ABD and improving the repair effect.

Study on the regulatory effect of Panax notoginseng saponins combined with bone mesenchymal stem cell transplantation on IRAK1/TRAF6-NF-κB pathway in patients with diabetic cutaneous ulcers

Panax notoginseng saponins (PNSs) have been found as the major active ingredient of Panax notoginseng (Burkill) F.H.Chen (PN) leaves, which has the effect of reducing inflammatory response, facilitating fibroblast proliferation, as well as promoting angiogenesis. This study aimed to investigate the molecular basis of PNS combined with bone mesenchymal stem cells (BMSCs) for treating diabetic cutaneous ulcers (DCU) and its mechanism of action. Methods. A total of 75 SD rats were selected to make diabetic cutaneous ulcers model. According random number table method, the rats were randomly divided into a control group, a DCU group, a BMSCs group, a PNS group and BMSCs + PNS group. Five groups of rats were given without treatment. After being treated for 7 days, the rats were anesthetized with pentobarbital, and granulation tissue was collected from the central point of the wound. They were used for pathological analysis, Western blot (WB) and polymerase chain reaction (PCR) assays. Results. The wound healing area was the largest in the BMSCs + PNS group. HE staining results showed that the PNS + BMSCs group could promote the formation of new epidermis and reduce the infiltration of inflammatory cells. Immunohistochemistry (IHC) results showed that the PNS + BMSCs group could up-regulate the expression of Ki67 protein and cell proliferation. In addition, PNS combined with BMSCs up-regulated the expression of miR-146-5p and down-regulated the expression of IL-1β, IL-6 and TNF-α, IRAK1, TRAF6 and p65 in the NF-κB signaling pathway (p < 0.05). Conclusions. PNS combined with bone mesenchymal stem cell transplantation up-regulated miR-146a-5p targeting and binding to IRAK1/TRAF6, inhibiting the activation of NF-κB pathway, which reduced the inflammatory response of DCU and facilitated the skin healing of DCU. Thus, this study provides a theoretical basis and a novel therapeutic option for the treatment of DFU with PNS combined with BMSCs.

Magnetic resonance imaging assessment of the therapeutic effect of combined electroacupuncture and stem cells in acute peripheral nerve injury.

Objectives: This study aimed to evaluate the therapeutic effect of a combination of Bone Mesenchymal stem cells (BMSCs) transplantation and Electroacupuncture (EA) for acute sciatic nerve injury in rats using magnetic resonance. Methods: Ninety-two male adult healthy Sprague-Dawley rats were randomly divided into the EA+BMSCs group, EA group, MSCs group, and PBS group (control). Electroacupuncture was performed on a rat receiving EA treatment at Huantiao (GB30) and Zusanli (ST36). T2 values and diffusion tensor imaging (DTI) derived from multiparametric magnetic resonance imaging (MRI), histological assessments, and immunohistochemistry was used to monitor nerve regeneration. Walking track analysis was used to assess nerve functional recovery. Repeated-measures one-way analysis of variance was used to evaluate the significance of T2, DTI, and SFI values among the four groups. One-way analysis of variance was used for comparing the histological characteristics. Bonferroni test was used for multiple pairwise comparisons at each time point. Results: In terms of FA, the EA+BMSCs and EA groups had faster recovery than PBS (control) in all time points after surgery, and the EA+BMSCs group recovered better than the BMSCs group at 3 weeks (P ≤ 0.008). FA values were higher in the EA group than in the BMSCs group at 4 weeks (P ≤ 0.008). In terms of RD, the EA+BMSCs group recovered better than the BMSCs group at 2 and 4 weeks (P ≤ 0.008). Immunofluorescence staining for axon guidance molecule netrin-1 revealed that it was significantly higher in the EA+BMSCs subgroup and EA subgroup than it was in the control (PBS) subgroup at 1-3 weeks (P < 0.001). Immunofluorescence staining for S100 showed the continuity of nerve fibers recovered more quickly in the EA+BMSCs subgroup than in the BMSCs subgroup. Conclusion: Our research revealed that a combination of MSCs and EA can provide both topological and biomolecular guidance to promote axonal extension, myelin regeneration, and functional recovery after PNI. EA not only promotes nerve repair on its own, but also enhanced the beneficial effects of stem cell treatment and the secretion of netrin 1, a guidance regeneration factor, and promotes the orderly growth of nerve fibers. These PNI repairs could be monitored non-invasively and in situ by MRI. The FA and RD values derived from MRI could be sensitive biomarkers to reflect the PNI repair process.

Bone Marrow Mesenchymal Stem Cells (BMSCs) Promote the Repair of Spinal Cord Injury Nerve Cells by Regulating the Toll-Like Receptor 4/Nuclear Transcription Factor-Kappa B (TLR4/NF-κB) Signaling Pathway

To explore the role of bone mesenchymal stem cells (BMSCs) transplantation and erythropoietin (EPO) in repairing nerve function after spinal cord injury (SCI) in rats. SCI SD model rats (n = 60) were randomly assigned into control group, BMSCs group, combined group (BMSCs combined with EPO treatment) with 20 rats in each group followed by analysis of rat nerve function on day 1, 3, 7, 14 and 28 after SCI using BBB scoring standard, cell apoptosis by TUNEL kit staining along with detection of NF200 expression. On day 7, 14, and 28 after SCI, BBB scores of BMSCs group and both the BMSCs group and the combined group had significantly higher BBB scores (P &lt; 0.05), and the combined group had a higher BBB score (P &lt; 0.05). On day 1, 3, 7, 14 and 28 after SCI, the apoptosis index of BMSCs group and combination group were significantly reduced (P &lt; 0.05) with more reduction in combination group than BMSCs group (P &lt; 0.05). Meanwhile, BMSCs group and combination group presented increased NF200 expression and BrdU positive rate compared to control group (P &lt; 0.05). In SCI rats, the combined use of BMSCs transplantation and EPO therapy can effectively reduce cell apoptosis, upregulate neurofilament protein, and effectively promote recovery of nerve function.

Collagen Nanofilm-Coated Partially Deproteinized Bone Combined With Bone Mesenchymal Stem Cells for Rat Femoral Defect Repair by Bone Tissue Engineering.

The advantages of good biocompatibility, low degradation and low antigenicity of collagen, and the osteogenic differentiation characteristics of bone mesenchymal stem cells (BMSCs) were used to promote the recovery of bone defects using partially deproteinized bone (PDPB) by bone tissue engineering (BTE). The BMSCs were identified by examining their potential for osteogenic, lipogenic, and chondrogenic differentiation. The prepared pure PDPB was ground into bone blocks 4 × 2 × 2 mm in size, which were divided into the following groups: PDPB group, PDPB + collagen group, PDPB + collagen + BMSC group, PDPB with a composite collagen nanofilm, and BMSCs injected into the tail vein. At 2, 4, 6, and 8 weeks after surgery, the effects of the implants in the different groups on bone defect repair were continuously and dynamically observed through x-ray examination, gross specimen observation, histological evaluation, and microvascularization detection. Postoperative x-ray examination and gross specimen observation revealed that, after 4 to 8 weeks, the external contour of the graft was gradually weakened, and the transverse comparison showed that the absorption of the graft and fusion of the defect were more obvious in PDPB + collagen + BMSC group than in PDPB group and PDPB + collagen group, and the healing was better (P < 0.05). Hematoxylin and eosin staining of histological sections showed very active proliferation of trabecular hematopoietic cells in groups PDPB + collagen + BMSC and PDPB + collagen. Masson's trichrome staining for evaluation of bone defect repair showed that the mean percent area of collagen fibers was greater in PDPB + collagen + BMSC group than in the PDPB group, with degradation of the scaffold material and the completion of repair. Immunofluorescence staining showed significantly enhanced expression of the vascular marker CD31 in group C (P < 0.05). The proposed hybrid structure of the collagen matrix and PDPB provides an ideal 3-dimensional microenvironment for patient-specific BTE and cell therapy applications. The results showed that collagen appeared to regulate MSC-mediated osteogenesis and increase the migration and invasion of BMSCs. The combination of collagen nanofilm and biological bone transplantation with BMSC transplantation enhanced the proliferation and potential of the BMSCs for bone regeneration, successfully promoting bone repair after implantation at the defect site. This method may provide a new idea for treating clinical bone defects through BTE.

Bone Mesenchymal Stem Cells Contribute to Ligament Regeneration and Graft-Bone Healing after Anterior Cruciate Ligament Reconstruction with Silk-Collagen Scaffold.

Anterior cruciate ligament (ACL) reconstruction was realized using a combination of bone mesenchymal stem cells (BMSCs) and silk–collagen scaffold, and an in vivo evaluation of this combination was performed. By combining type I collagen and degummed silk fibroin mesh, silk–collagen scaffolds were prepared to simulate ligament components. BMSCs isolated from bone marrow of rabbits were cultured for a homogenous population and seeded on the silk–collagen scaffold. In the scaffold and BMSC (S/C) group, scaffolds were seeded with BMSCs for 72 h and then rolled and used to replace the ACL in 20 rabbits. In the scaffold (S) group, scaffolds immersed only in culture medium for 72 h were used for ACL reconstruction. Specimens were collected at 4 and 16 weeks postoperatively to assess ligament regeneration and bone integration. HE and immunohistochemical staining (IHC) were performed to assess ligament regeneration in the knee cavity. To assess bone integration at the graft–bone interface, HE, Russell–Movat staining, micro-CT, and biomechanical tests were performed. After 4 weeks, vigorous cell proliferation was observed in the core part of the scaffold in the S/C group, and a quantity of fibroblast-like cells and extracellular matrix (ECM) was observed in the center part of the graft at 16 weeks after surgery. At 4 and 16 weeks postoperatively, the tenascin-C expression in the S/C group was considerably higher than that in the S group (4 w, p < 0.01; 16 w, p < 0.01). Furthermore, bone integration was better in the S/C group than in the S group, with histological observation of trabecular bone growth into the graft and more mineralized tissue formation detected by micro-CT (4 w, bone volume fraction (BV/TV), p = 0.0169, bone mineral density (BMD), p = 0.0001; 16 w, BV/TV, p = 0.1233, BMD, p = 0.0494). These results indicate that BMSCs promote ligament regeneration in the knee cavity and bone integration at the graft–bone interface. Silk–collagen scaffolds and BMSCs will likely be combined for clinical practice in the future.

The effects of oyster shell/alpha-calcium sulfate hemihydrate/platelet-rich plasma/bone mesenchymal stem cells bioengineering scaffold on rat critical-sized calvarial defects.

Engineering scaffolds combining natural biomineral and artificially synthesized material hold promising potential for bone tissue regeneration. We fabricated a bioengineering scaffold, oyster shell (OS) and alpha-calcium sulfate hemihydrate (α-CSH) as scaffold, platelet-rich plasma (PRP) as provider of growth factors and bone mesenchymal stem cells (BMSCs) as seed cells, and determined it could be applied as a new type of bone graft substitutes by rat calvarial defects repairing experiment in vitro and in vivo. SEM showed that the mean diameter of the pores was about 150 μm with a range of 50-200 μm, and scaffold's porosity was ~27.4% by Archimedes' Principle. In vitro, Scaffold + BMSCs + PRP group presented a higher ALP activity compared with other groups by ELISA (P < 0.05). But the expression of OC was not detectable on day 4 or 8. The MTT assay showed that the relative cell number of BMSCs+PRP group increased significantly (P < 0.05). In vivo, the smallest defect area of skull and highest volume of regenerated new bone were observed in Scaffold + PRP + BMSCs group by X-ray and Micro-CT analysis (P < 0.05). And the similar results also were observed in HE and Masson staining. The immunohistochemistry staining for osteogenic marker proteins ALP and OC showed that the most obvious positive staining was observed in Scaffold + PRP + BMSCs group (P < 0.05). The expression of inflammatory markers IL-6 and TNF-α was the lowest in control group (P < 0.05). In conclusion, a bioengineering scaffold based on OS, created by simply combining α-CSH and PRP and implanting with BMSCs, could be clinically useful and has marked advantages as a targeted, off-the-shelf, cell-loaded treatment option for the bone healing of critical-size calvarial defects.

Human gingiva marrow-derived stromal cells exert immunoprotection on rat liver transplantation model through regulating FAS/FASL pathway

BackgroundMarrow mesenchymal stem cells (MSCs), especially bone MSCs (BMSCs), play a vital role in immunomodulation of graft rejection but many shortcomings limit its application. In this study, we aimed to investigate the modulation effect of MSCs from gingiva (GMSCs) on the rejection of rat liver transplantation model and to explore the potential mechanisms. MethodsGMSCs were obtained from human gingival tissues and BMSCs were harvested from Brown Norway (BN) rats. The siRNA that mediated knockdown of Fas ligand (FASL) expression in GMSCs (FASL-/-GMSCs) was transfected using lentivirus plasmid. Rat orthotopic liver transplantation model was established. The rats were divided randomly into four groups: normal saline (NS) group, FASL-/-GMSCs group, BMSCs group, and GMSCs group, all of which were injected the solution via dorsal vein of penis to construct the rat rejection model Graft survival and liver function indexes were measured. The immunological reactions of recipients including immune-cytokines, T-helper type 17 (Th17) and regulatory T cells (Treg) were also evaluated by flow cytometry. ResultsThe graft survival of recipient rats in the GMSCs group was significantly prolonged in comparison with that of the NS, FASL-/-GMSCs and BMSCs group. GMSCs remarkably decreased the levels of AST, ALT and TBIL. As for immune-cytokines, serum levels of IL-2, IFN-γ and Th 17 in recipient rats from the GMSCs group reduced significantly compared with that of other three groups, while increased serum IL-10 and TGF-β expressions as well as peripheral serum Treg were also observed in GMSCs group. ConclusionGMSCs exert immunoprotection on liver transplants by regulating FAS-FASL pathway. The current study firstly provides basis for GMSCs to be used in clinical anti-rejection after liver transplantation.

Deletion of miR-126a Promotes Hepatic Aging and Inflammation in a Mouse Model of Cholestasis

MicroRNAs (miRNAs) act as regulators of aging at the tissue or organism level or as regulators of cellular senescence. Targeted deletion of miR-126 in mice causes partial embryonic lethality, but its biological function in the liver is still largely unknown. Here, we deleted miR-126a, using the CRISPR/Cas9 system in vitro and in vivo. miR-126a was reduced in the aging livers, and disruption of miR-126a in bone mesenchymal stem cells (BMSCs) induced age-associated telomere shortening, DNA damage responses, and proinflammatory cytokines. Moreover, disruption of miR-126a in mice caused hepatocyte senescence, inflammation, and metabolism deficiency. In addition, disruption of miR-126a via BMSC transplantation aggravated the severity of liver defects induced by cholestasis compared with that in the functional miR-126a BMSC group. Mechanistically, we identified versican (VCAN) as a novel direct miR-126a-5p target that induces telomere shortening, BMSC senescence, and nuclear factor κB (NF-κB) pathway activation. This study identified aging-related reduced expression of miR-126a and promotion of its target VCAN as a key mechanism in the regulation of hepatic metabolic function during aging and hepatic damage by inducing NF-κB pathway activation, DNA repair function disorder, and telomere attrition. The findings indicate that miR-126a may be a drug target for the treatment of hepatic failure.

Therapeutic Effects of VEGF Gene-Transfected BMSCs Transplantation on Thin Endometrium in the Rat Model.

Objective Bone mesenchymal stem cells (BMSCs) transplantation has a therapeutic effect on the thin endometrium in animal researches and clinical trials. The present study aims at assessing whether transplantation of VEGF-transfected BMSCs (VEGF-BMSCs) have a better therapeutic effect on endometrial regeneration and endometrial receptivity compared with BMSCs therapy alone. Methods Sprague-Dawley (SD) rats were used in the study. Thin endometrium model was established with 95% ethanol injection into uterine. VEGF-BMSCs or BMSCs was transplanted via tail vein IV injection. Endometrial thickness, morphology, and pinopodes were assessed by hematoxylin and eosin (HE) staining and scanning electron microscope (SEM). The proteins and mRNAs expressions of markers for endometrial cells and endometrial receptivity were measured after treatment. The fertility testing was done to assess the embryo implantation efficiency. Results VEGF-BMSCs transplantation significantly increased endometrial thickness compared with the BMSCs group and the control group. There was no significant difference in endometrial thickness between VEGF-BMSCs group and sham operation group. Importantly, in protein level, expressions of cytokeratin, vitamin, VEGF, LIF, and integrin ανβ 3 in VEGF-BMSC group were increased dramatically compared with those of the control group and BMSC group both 4 days and 8 days after stem cells transplantation. Accordingly, mRNA expression of LIF and integrin α ν β 3 was significantly upregulated compared with those of the control group and BMSC group both 4 and 8 days after treatment. The pinopodes were developed better in the VEGF-BMSCs group and the sham operation group compared with BMSCs group and the control group. The number of embryo implantation is largest in the sham operation group, followed by VEGF-BMSCs group, BMSCs group, and the control group. Conclusions Transplantation of VEGF gene-transfected BMSCs may be a better therapeutic treatment for thin endometrium than stem cell therapy alone.

Role of HMGB1-RAGE/TLRs-NF-κB signaling pathway on bone mesenchymal stem cells transplantation therapy for lipopolysaccaride-induced coagulation disorder rats

To determine the effect of bone mesenchymal stem cells (BMSCs) in transplantation therapy for lipopolysaccharide (LPS)-induced coagulation disorder and the underlying mechanism of high mobility group protein B1-receptors for advanced glycation end products/Toll-like receptors-nuclear factor-κB (HMGB1-RAGE/TLRs-NF-κB) signaling pathway. BMSCs of female Sprague-Dawley (SD) rats ageing 4-5 weeks old were extracted and cultivated in vitro, and the fourth-passaged BMSCs phenotype was identified by flow cytometry for transplantation in the following experimental study. The rats were randomly divided into normal saline (NS) control group, LPS group, and BMSC group according to the random number table with 15 rats in each group. Coagulation disorders model was reproduced by injection of 1 mg/kg LPS via saphenous vein, and the rats in the NS control group was injected with equal volume NS. Those in the BMSC group were infused BMSC 0.5 mL containing 1×106 cells via tail vein at 2 hours after LPS injection, and the rats in other groups were injected with equal volume NS. Abdominal aorta blood was collected at 1, 3 and 7 days post operation. Coagulation indexes such as platelet count (PLT), platelet volume distribution width (PDW), mean platelet volume (MPV), plateletcrit (PCT), platelet large cell ratio (P-LCR), activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), international normalized ratio (INR), and fibrinogen (FIB) were determined. The mRNA levels and contents of HMGB1, RAGE, TLR2/4 and NF-κB were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. (1) The cells cultured in vitro were spindle shaped or flat. The fourth-passaged BMSCs phenotype was successfully identified by flow cytometry technology. (2) Coagulation indexes: compared with NS control group, PLT, PCT and FIB in LPS group were significantly decreased, PDW, MPV, P-LCP, and INR were significantly increased, and APTT, PT, and TT were significantly prolonged from the first day. Furthermore, those in LPS group were gradually ameliorated with prolongation of LPS induction time. The coagulation function abnormality induced by LPS was reversed by BMSCs with significant difference at 1 day as compared with LPS group [PLT (×109/L): 398.8±17.9 vs. 239.1±15.8, PCT (%): 0.35±0.04 vs. 0.23±0.06, FIB (g/L): 1.7±0.6 vs. 0.8±0.1, PDW (%): 12.4±1.6 vs. 16.2±1.5, MPV (fl): 11.0±1.6 vs. 13.7±1.1, P-LCP (%): 13.0±2.1 vs. 15.3±2.7, INR: 1.52±0.17 vs. 1.82±0.19, APTT (s): 66.3±4.1 vs. 89.5±4.5, PT (s): 18.3±0.7 vs. 25.1±1.9, TT (s): 87.5±7.8 vs. 115.0±9.7, all P < 0.05], till 7 days. (3) HMGB1-RAGE/TLRs-NF-κB signaling pathway related molecules: compared with NS control group, the mRNA expressions and contents of HMGB1, RAGE, TLR2/4 and NF-κB were significantly increased in LPS group from the first day. However, the mRNA expressions and contents of the molecules in LPS group were gradually decreased with prolongation of LPS induction time. After BMSC intervention, the mRNA expressions and contents of molecules at 1 day were significantly lower than those of LPS group [HMGB1 mRNA (2-ΔΔCt): 10.77±0.04 vs. 24.51±3.69, HMGB1 content (μg/L): 0.48±0.01 vs. 0.95±0.06; RAGE mRNA (2-ΔΔCt): 11.57±1.11 vs. 18.08±0.29, RAGE content (μg/L): 0.73±0.04 vs. 1.37±0.06; TLR2 mRNA (2-ΔΔCt): 2.60±0.22 vs. 12.61±0.27, TLR2 content (μg/L): 0.81±0.03 vs. 1.59±0.09; TLR4 mRNA (2-ΔΔCt): 2.95±0.52 vs. 4.06±0.11, TLR4 content (μg/L): 0.80±0.09 vs. 1.18±0.11; NF-κB mRNA (2-ΔΔCt): 1.29±0.06 vs. 7.79±0.25, NF-κB content (μg/L): 1.22±0.24 vs. 2.42±0.26, all P < 0.05], till 7 days. BMSCs administration could ameliorate the coagulation function in LPS-induced coagulation disorder rats and these might be associated with HMGB1-RAGE/TLRs-NF-κB signaling pathway inhibition.

Catalpol Promotes the Survival and VEGF Secretion of Bone Marrow-Derived Stem Cells and Their Role in Myocardial Repair After Myocardial Infarction in Rats.

Bone mesenchymal stem cells (BMSCs) transplantation has been recognized as an effective method for the treatment of myocardial infarction (MI). However, its efficacy is always restricted by the low survival of transplanted BMSCs in the ischemic myocardium. The aim of this study was to investigate the effect of catalpol pre-treatment on the survival and vascular endothelial growth factor (VEGF) secretion of BMSCs under oxygen glucose deprivation (OGD) condition and their role in myocardial repair in a rat model of MI. According to our results, pre-treatment with catalpol enhanced VEGF secretion and survival of OGD-treated BMSCs. Moreover, the apoptosis of BMSCs induced by OGD was restrained by catalpol as evidenced by increased level of B-cell lymphoma-2 (Bcl-2) and decreased levels of BCL2-associated X (Bax) and cleaved caspase-3. In vivo study suggested that the survival of transplanted BMSCs was improved by catalpol pre-treatment. The myocardial fibrosis and apoptosis was further inhibited in catalpol pre-treated BMSCs group. Cardiac function detected by echocardiography was obviously improved by catalpol pre-treated BMSCs transplantation. Finally, angiogenesis and VEGF expression in the ischemic myocardium were significantly promoted in catalpol pre-treated BMSCs group. In conclusion, catalpol pre-treatment may facilitate the survival and VEGF secretion of BMSCs and improve their therapeutic effect on MI.

Integrin β1 Increases Stem Cell Survival and Cardiac Function after Myocardial Infarction.

Bone mesenchymal stem cells (BMSCs) transplantation is a promising therapeutic approach for myocardial infarction (MI), but its application is limited by poor viability of BMSCs. In this study, we aimed to improve the survival of BMSCs by lentivirus vector mediated overexpression of integrin β1. In vitro study showed that integrin β1 overexpression could facilitate the proliferation of BMSCs under oxygen glucose deprivation condition and regulated the expression of Caspase-3, Bax, Bcl-2, FAK, and ILK in BMSCs. Next, MI was induced in rat model and Igtb1BMSCs, NullBMSCs, or NatBMSCs were transplanted by intramyocardial injection. One week later, the survival of BMSCs was higher in Itgb1 BMSCs group than in other groups. Four weeks after transplantation, heart function was significantly improved in Igtb1BMSCs group compared to other groups. The expression levels of Caspase-3 and Bax were decreased while the expression levels of Bcl-2, FAK, ILK, and VEGF were increased in the cardiomyocytes of Igtb1BMSCs group compared to other groups. In conclusion, integrin β1 overexpression could increase the survival of BMSCs and improve the efficacy of transplanted BMSCs for MI treatment. The beneficial effects may be mediated by inhibiting the apoptosis of both transplanted BMSCs and cardiomyocytes through adhesion-mediated cell survival signaling.

Effect of bone mesenchymal stem cells transplantation on neurological function and learning and memory of traumatic brain injury rats by the external carotid artery

Objective To study the effect of bone mesenchymal stem cells(BMSC) transplantation into traumatic brain injury(TBI) rats by the external carotid artery on neurological function and learning and memory. Methods Ten adult SD rats were randomly divided into TBI group (n=5) and BMSC transplantation group (n=5). Feeney free falling method was used to establish TBI models. The experimental rats were administrated with BMSC via external carotid artery (ECA), while TBI rats were injected with sterile liquid medium of equal volume via right ECA.Neurological function were evaluated according to the modified neurological severity score (NSS) at 1, 3, 7, 15 days.Morris water maze test was used to observe the animal capabilities of place navigation and space exploration at 15 days, then animals were sacrificed. Survival and migration of implanted BMSC in brains under fluorescence microscope. Result After traumatic brain, varying degrees convulsions, paralysis, loss of balance function in rats were found.Compared with TBI group, BMSC transplantation decreased significantly NSS (P<0.01). BMSC transplantation significantly decreased on escape latency((20.48±2.29)s) than the TBI group((85.93±47.48)s) (P<0.01). Moreover, BMSC group in the target quadrant dwell time ((28.62±1.72)%) and distance ((29.05±3.08)%) as well as the number of passing the platform (8.00±2.45) were significantly higher than the TBI group ((19.37±2.81)%, (21.78±3.06)%, (2.00±1.87) respectively, P<0.01). Transplanted BMSC could survive and migrate around injury brain through Hochest mark immunofluorescence. Conclusion BMSC can survive and migrate around injury brain by transplantation of external carotid artery, which results in a significant neurological function improvement and learning and memory increase in rats with traumatic brain injury. Key words: Brain trauma; BMSC graft; External carotid artery; Neurological function; Learning and memory

The protective effect of bone marrow mesenchymal stem cells carrying antioxidant gene superoxide dismutase on paraquat lung injury in mice

To explore the possible mechanism and protective effect of BMSCs (bone mesenchymal stem cells) carrying superoxide dismutase (SOD) gene on mice with paraquat-induced acute lung injury. To establish the cell line of BMSCs bringing SOD gene, lentiviral vector bringing SOD gene was built and co-cultured with BMSCs. A total of 100 BALB/c mice were randomly divided into five groups, namely Control group, poisoning group (PQ group) , BMSCs therapy group (BMSC group) , BMSCs-Cherry therapy group (BMSC-Cherry group) , BMSCs-SOD therapy group (BMSC-SOD group) . PQ poisoning model was produced by stomach lavaged once with 1 ml of 25 mg/kg PQ solution, and the equal volume of normal saline (NS) was given to Control group mice instead of PQ. The corresponding BMSCs therapy cell lines were delivered to mice through the tail vein of mice 4h after PQ treatment.Five mice of each group were sacrificed 3 d, 7 d, 14 d and 21 days after corresponding BMSCs therapy cell lines administration, and lung tissues of mice were taken to make sections for histological analysis. The serum levels of glutathione (GSH) , malondialdehyde (MDA) , SOD, and the levels of transforming growth factor-β (TGF-β) and tumor necrosis factor-α (TNF-α) in lung tissue were determined. The level of SOD was assayed by Westen-blot. Compared with Control group, the early (3 days) levels of SOD protein in lung tissue of PQ group obviously decreased, and the late (21 days) levels of SOD obviously increased, while in therapy groups, that was higher than that in PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) . Compared with Control group, the levels of plasma GSH and SOD of PQ group and each therapy group wae significantly lower than those in Control group, while in therapy groups, those were higher than those of PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) .Compared with Control group, the level of plasma MDA, TNF-α and TGF-β in PQ group and therapy groups were significantly higher, while in therapy groups, that was lower than that in PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) . Lung biopsy showed that, the degree of lung tissue damage in each therapy group obviously reduced. SOD is the key factor of the removal of reactive oxygen species (ROS) in cells, that can obviously inhibit the oxidative stress damage and the apoptosis induced by PQ, thus significantly increasing alveolar epithelial cell ability to fight outside harmful environment.

Repair of transversal spinal cord injury in rats by porous silk fibroin scaffolds seeded with bone mesenchymal stem cells

Objective To investigate the therapeutic effects of porous silk fibroin scaffolds (PSFSs) seeded with bone mesenchymal stem cells (BMSCs) on the repair of transversal spinal cord injury (SCI) in rats.Methods Ninety-six SD rats were randomly divided into control group,PSFSs group,BMSCs group and PSFSs plus BMSCs group (24 each).The function repair was evaluated by Basso-Beattie-Bresnahan (BBB) score system at lst,2nd and 4th week.Immunohistochemistry and Western blotting were applied to detect the expression of growth associated protein 43 (GAP-43) and myelin basic protein (MBP) in the injured spinal cord.The intensity of GAP-43 expression was measured by immuno-fluorescence staining.Results At 4th week after injury,the implanted groups exhibited a more significant improvement in hindlimb locomotor function than in control group in BBB scores (P ＜0.05).The BBB sores in control group,PSFSs group,BMSCs group and PSFSs plus BMSCs group were 5.23 ± 1.13,7.17 ±1.11,7.35 ± 1.59 and 9.43 ± 2.16 respectively.Immunohistochemistry showed that the integral absorbance (IA) values of GAP-43 and MBP in implanted groups were significantly higher than those in control group (P ＜ 0.05).In control group,PSFSs group,BMSCs group and PSFSs plus BMSCs group,the IA values of GAP-43 were 13.94 ±3.63,26.07 ±5.31,22.14 ±4.56 and 33.03 ±7.58,and those of MBP were 13.80 ± 3.41,21.16 ± 3.36,32.96 ± 7.74 and 44.06 ± 7.99,respectively.The immuno-fluorescence staining indicated that there were more GAP-43 positive growth cones at the lesion site in PSFSs plus BMSCs group.Western blotting results showed that there was significant difference in the expression of GAP-43 and MBP proteins between control group and implanted groups (P ＜ 0.05).In control group,PSFSs group,BMSCs group and PSFSs plus BMSCs group,the gray value ratio of GAP-432 was 0.16 ± 0.04,0.41 ±0.05,0.33 ±0.06 and 0.72 ±0.16,and that of MBP was 0.96 ±0.11,1.85 ±0.08,2.14 ±0.16 and 2.43 ± 0.31,respectively.Conclusion Transplantation of PSFSs seeded with BMSCs can promote the axonal regeneration,myelination and functional recovery after SCI in rats. Key words: Spinal cord injury; Bone mesenchymal stem cells; Silk fibroin; Transplantation

A comparative study on rabbit bone mesenchymal stem cells and human amniotic epithelial cells transplantation for rabbit limbal stem cell deficiency

Background Limbal stem cell deficiency usually leads to blindness, and traditional therapy is limited. Recent research demonstrated that bone mesenchymal stem cells ( BMSCs ) and human amniotic epithelial cells(AECs) could differentiate into many kinds of cells including corneal epithelial cells, but the outcome and effect of these cells on corneal stem cell deficiency are still unclear. Objective This study aimed to observe and compare the effects of rabbit BMSCs and human AECs transplantation for rabbit limbal stem cell deficiency. Methods Eighteen clean New Zealand rabbits were randomly divided into the amniotic stroma(AS) group, rabbit BMSCs group and human AECs group with 6 rabbits for each group. Limbal stem cell deficiency models were established by putting a piece of filter paper that had been soaked in a NaOH solution at the corneal center. Rabbit BMSCs were isolated and purified by density gradient centrifugation combined with the attachment culture method, and human AECs were collected by a sequential trypsin digestion technique,and the third generation rabbit BMSCs and the first generation human AECs were identified with RT-PCR. After that,cells were inoculated onto the denuded AS and grafted to the corneal surface of the experimental animals. Twenty-eight days after cell transplantation, the therapeutic effects were evaluated based on the corneal neovascularization and opacity scores. Corneal histopathological examination and immunohistochemistry were performed to evaluate and compare the effectiveness among AS,rabbit BMSCs and human AECs on corneal stem cell deficiency. The procedure complied with the Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission. Results The third generation of rabbit BMSCs grew well after 12 hours, and the first generation of human AECs formed a membrane-like monolayer after 48 hours of incubation on AS. Immunohistochemistry staining showed that, 28 days after transplantation, the surface cells of the cornea were positive for cytokeratin 3 in both the rabbit BMSCs group and human AECs group.Compared with the AS group,the corneal neovascularization and opacity grades were significantly decreased in the rabbit BMSCs group( Z=-2. 983, P =0. 003 ; Z =-2. 844, P =0. 004 ) and human AECs group ( Z =-2. 817, P =0. 005 ; Z =-2.041, P =0. 041 ). Histopathological analysis exhibited that stratified corneal epithelial-like cells formed on the corneal stroms 28 days after grafting and no signs of goblet cells and neovascularization were found. Less inflammatory cells and regular collagen fiber could be seen in the rabbit BMSCs group and human AECs group. In addition,clinical observation also revealed that the corneas were much clearer in the rabbit BMSCs group than the human A ECs group( Z =-2. 091 , P=0. 037 ), but the corneal neovascularization score was similar between them (Z = -0. 267,P=-0. 789). Conclusions Rabbit BMSCs and human AECs can differentiate into corneal epithelial-like cells on the damaged corneal surface and further demonstrate remarkable inhibitory effects on corneal neovascularization and inflammatory cells. The more dominant and prominent effect is the role played by rabbit BMSCs in the improvement of corneal transparency. Key words: Bone mesenchymal stem cell; Amniotic epithelial cell; Limbal stem cell; Corneal neovascularization; Stem cell transplantation

Effect of HA1077 on mesenchymal stem cells promoting wound healing

Objective To observe the effect and mechanism of HA1077 on bone mesenchymal stem cells (BMSCs) promoting wound healing. Methods (1) In vitro study: rats' BMSCs were har-vested and divided into three groups randomly, ie, control group, induction group and HA1077 group. In control group, culture medium was DMEM with 10% fetal bovine serum. In induction group, induction medium was DMEM which consisted of 10% FBS, 8μg/ml EGF and epithelium culture condition medi-um. In HA1077 group, culture condition medium was the induction medium pins 10 μmol/L HA1077. At day 7 after replanting, CK19 expression, PCNA expression and cell cycle among three groups were clarified by flow cytometry. (2) In vivo study: rabbit's BMSCs were isolated. Six pieces of full skin loss wound were created on the back of a rabbit, with three pieces of wound on the half side of back. The wound was round and 3 cm in diameter. Eight New Zealand rabbits were randomly divided into four groups, ie, control group (Group A), EGF control group (Group B), BMSCs group (Group C) and BMSCs + HA1077 group (Group D). Wounds were treated by normal saline in Group A and by EGF (50 U/cm2) in Group B. Besides EGF,1 ml of BMSCs suspension (2 × 106/ml) was used for wound re-pair in Group C. 0.5 ml HAIO77(20 μmol/L), BMSCs and EGF were used together for wound repair in GronpD. At days3, 7and 14 after injury, wound elosuroindex (WCI) was calculated. Results In vitro study:the positive rate of CK19 in the HA1077 group was (40.31±0.82)%, higher than (11.13±2.14)% in the induction group(P < 0.01). The PCNA positive rate and the S phase, cell quantity in HA1077 group were also higher than that in the induction group. In vivo study: WCI was (86.20±1.92) % in Group D at day 14 after injury, obviously higher than that in other three groups. Conclusions HA1077 can promote BMSCs' entering into S phase, expressing PCNA and differentiating and expressing CK19. In vivo combination of HA1077 with BMSCs may facilitate wound healing. Key words: Mesenchymal stem cells; Wound; HA1077