The effect of neuropeptides on proliferation of rat bone marrow mesenchymal stem cells

Objective To investigate the effects and mechanism of calcitonin gene-related peptide(CGRP)and substance P (SP) on proliferation of rat bone marrow mesenchymal stem cells.Methods The rBMSCs were isolated using whole bone marrow

Micro RNA-9 promotes the neuronal differentiation of rat bone marrow mesenchymal stem cells by activating autophagy

MicroRNA-9 （miR-9） has been shown to promote the differentiation of bone marrow mesen-chymal stem cells into neuronal cells, but the precise mechanism is unclear. Our previous study conifrmed that increased autophagic activity improved the efifciency of neuronal differentiation in bone marrow mesenchymal stem cells. Accumulating evidence reveals that miRNAs adjust the autophagic pathways. This study used miR-9-1 lentiviral vector and miR-9-1 inhibitor to modulate the expression level of miR-9. Autophagic activity and neuronal differentiation were measured by the number of light chain-3 （LC3）-positive dots, the ratio of LC3-II/LC3, and the expression levels of the neuronal markers enolase and microtubule-associated protein 2. Re-sults showed that LC3-positive dots, the ratio of LC3-II/LC3, and expression of neuron speciifc enolase and microtubule-associated protein 2 increased in the miR-9＋ group. The above results suggest that autophagic activity increased and bone marrow mesenchymal stem cells were prone to differentiate into neuronal cells when miR-9 was overexpressed, demonstrating that miR-9 can promote neuronal differentiation by increasing autophagic activity.

Brain-derived neurotrophic factor genes transfect rat bone marrow mesenchymal stem cells based on cationic polymer vector

BACKGROUND： Gene therapy is an effective expression of genes within target cells after transferring exogenous target genes. Both vector selection and transfection method are important factors for gene transfection. An ideal gene vector is required for a high transfusion of target gene and an exact introduction of target gene into specific target cells so as to express gene products. OBJECTIVE： To study the expression of mRNA and protein after transfecting rat bone marrow mesenchymal stem cells （BMSCs） with brain-derived neurotrophic factor （BDNF） genes based on cationic polymer vector. DESIGN, TIME AND SETTING： A randomized, controlled in vitro study using gene engineering, performed at the Neurobiology Laboratory, Xuzhou Medical College between October 2007 and April 2008. MATERIALS： PcDNA3.1 BDNF was obtained from Youbiai Biotechnological Company, Beijing and cationic polymer vector used was the SofastTM gene transfection reagent that was made by Taiyangma Biotechnological Co., Ltd., Xiamen. METHODS： BMSCs extracted from six Sprague Dawley （SD） rats aged 1 month were isolated and cultured in vitro. Third passage BMSCs were inoculated on a 6-well culture plate at the density of 1×106 cells/L. At about 80% confluence, BMSCs were transfected with PcDNA3.1-BDNF （2 μg） combined with SofastTM gene transfection reagent （6 μg） （BDNF group） or with PcDNA3.1 （2 μg） combined with SofastTM gene transfection reagent （6 μg） （blank vector group）. Cells that were not transfected with any reagents but still cultured under primary culture conditions were used as a non-transfection group. MAIN OUTCOME MEASURES： Enzyme linked immunosorbent assay was used to measure time efficiency of BMSC-secreted BDNF protein. Twenty-four hours after gene transfection, RT-PCR was used to detect expression of BDNF mRNA in the BMSCs. Immunohistochemistry was used to determine expression of BDNF protein in the BMSCs. RESULTS： BDNF protein expression was detected at day 1 after gene transfection, rapidly increased after 5–9 days and gradually increased after 11–15 days in the BDNF group; moreover, BDNF protein expression was higher than that in the non-transfection group and the blank vector group at different time points （P 〈 0.01）. Additionally, BDNF mRNA expression in the BDNF group was higher than that in the blank vector group and the non-transfection group （P 〈 0.01）. CONCLUSION： A cationic polymer vector can effectively mediate the BDNF gene to transfect BMSCs; genetically modified BMSCs can express BDNF protein effectively for a long term.

Chondrogenic differentiation of rat bone marrow mesenchymal stem cells induced by puerarin and tetrandrine

Objective: This study aims to clarify the effect of the active components puerarin and tetrandrine on the chondrogenic differentiation of bone marrow mesenchymal stem cells(BMSCs).Methods: Using network pharmacology, protein targets of puerarin and tetrandrine were predicted, and a database of cartilage formation targets was established. The protein target information related to disease was then collected, and the drug-targeting network was constructed by analyzing the protein–protein interactions. Genes related to chondrogenesis induced by puerarin and tetrandrine and chondroblast differentiation signaling pathways were searched. Finally, potential drug-and disease-related genes,as well as proteins, were screened and verified using real-time RT-PCR and western blotting.Results: Network pharmacological studies have shown that puerarin and tetrandrine are involved in BMSCs cartilage differentiation. The experimental results showed that puerarin and tetrandrine could regulate the expression of cartilage differentiation-related genes and proteins. Puerarin increased the protein expression of COL2 A1, COL10 A1, MMP13, and SOX-9,as well as the gene expression of Col2 a1, Mmp13, Tgfb1, and Sox-9. Tetrandrine increased the protein expression of COL2 A1,COL10 A1, MMP13, and SOX-9, as well as the gene expression of Col10 a1, Tgfb1, Sox-9, and Acan. The combination of puerarin and tetrandrine increased the protein expression of COL2 A1, COL10 A1, MMP13, and SOX-9 and the gene expression of Col2 a1,Col10 a1, Sox-9, and Acan.Conclusions: Puerarin, tetrandrine, and their combination can promote the proliferation of BMSCs and induce their differentiation into chondrocytes, and they are thus expected to be inducers of chondrogenic differentiation. These results suggest that puerarin and tetrandrine have potential therapeutic effects on osteoarthritis.

In vitro cultivation of rat bone marrow mesenchymal stem cells and establishment of pEGFP/Ang-1 transfection method

Objective:To obtain the bone marrow mesenchymal stem cells(BMSCs).complete phenotypic identification and successfully transfecl rat BMSCs by recombinant plasmid pF.GFP/Ang-1.Methods:BMSCs were isolated from bone marrow using density gradient centrifugation method and adherence screening method,and purified.Then the recombinant plasmid pEGFP/Ang-1was used to transfect BMSCs and the positive clones were obtained by the screen of C418 and observed under light microscopy inversely.Green fluorescent exhibited by protein was enhanced to measure the change time of the expression amount of Ang-1.Results:BMSCs cell lines were obtained successfully by adherence screening method and density gradient ccntrifugation.Ang-1 recombinant plasmid was transfected smoothly into rat BMSCs,which can express Ang-1 for 3 d and decreased after 7 d.Conclusions:Adherence screening method und density gradient ceiilrifugation can be effective methods lo obtain BMSCs with high purity and rapid proliferation.Besides,the expression of transfected recombinant plasmid pEGFP/Ang-1 in rat BMSCs is satisfactory.

CO-TRANSFECTION OF RAT BONE MARROW MESENCHYMAL STEM CELLS WITH HUMAN BMP2 AND VEGF165 GENES

Objective To explore the feasibility and efficacy of lentivirus-mediated co-transfection of rat bone marrow mesenchymal stem cells （MSCs） with human vascular endothelial growth factor 165 （hVEGFI65） gene and human bone morphogenetic protein 2 （hBMP2） gene. Methods The hVEGF165 and hBMP2 cDNAs were obtained from human osteosarcoma cell line MG63 and cloned into lentiviral expression vectors designed to co-express the copepod green fluorescent protein （copGFP）. The expression lentivector and packaging Plasmid Mix were co-transferred to 293TN cells, which produced the lentivirus carrying hVEGF165 （Lv-VEGF） or hBMP2 （ Lv-BMP） , respectively. MSCs of Wistar rats were co-transfected with Lv-BMP and Lv-VEGF （BMP ＋ VEGF group）, or each alone （BMP group and VEGF group）, or with no virus （ Control group）. The mRNA and protein expressions of hVEGF165 and hBMP2 genes in each group were detected by real-time PCR and enzyme linked immunosorbent assay （ELISA）. Results Lentiviral expression vectors carrying hVEGF165 or hBMP2 were correctly constructed and confirmed by restriction endonucleses analysis and DNA sequencing analysis. A transfer efficiency up to 90% was archieved in all the transfected groups detected by the fraction of fluorescent cells using fluorescent microscopy. From the results generated by real-time PCR and ELISA, VEGF165 and BMP2 genes were co-expressed in BMP ＋ VEGF group. No significant difference of BMP2 expression was detected between BMP ＋ VEGF and BMP groups （ P 〉 0. 05）. Similarly, there was no significant difference of VEGF165 expression between BMP ＋ VEGF and VEGF groups （ P 〉 0. 05）. Conclusion VEGF165 and BMP2 genes were successfully co-expressed in MSCs by lentivirus-mediated co-transfection, which provided a further foundation for the combined gene therapy of bone regeneration.

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

Small extracellular vesicles from hypoxia-preconditioned bone marrow mesenchymal stem cells attenuate spinal cord injury via miR-146a-5p-mediated regulation of macrophage polarization

Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)help mediate the beneficial effects conferred by MSC transplantation following spinal cord injury.Strikingly,hypoxia-preconditioned bone marrow mesenchymal stem cell-derived SEVs(HSEVs)exhibit increased therapeutic potency.We thus explored the role of HSEVs in macrophage immune regulation after spinal cord injury in rats and their significance in spinal cord repair.SEVs or HSEVs were isolated from bone marrow MSC supernatants by density gradient ultracentrifugation.HSEV administration to rats via tail vein injection after spinal cord injury reduced the lesion area and attenuated spinal cord inflammation.HSEVs regulate macrophage polarization towards the M2 phenotype in vivo and in vitro.Micro RNA sequencing and bioinformatics analyses of SEVs and HSEVs revealed that mi R-146a-5p is a potent mediator of macrophage polarization that targets interleukin-1 receptor-associated kinase 1.Reducing mi R-146a-5p expression in HSEVs partially attenuated macrophage polarization.Our data suggest that HSEVs attenuate spinal cord inflammation and injury in rats by transporting mi R-146a-5p,which alters macrophage polarization.This study provides new insights into the application of HSEVs as a therapeutic tool for spinal cord injury.

Bone marrow mesenchymal stem cells in treatment of peripheral nerve injury

Peripheral nerve injury(PNI)is a common neurological disorder and complete functional recovery is difficult to achieve.In recent years,bone marrow mesenchymal stem cells(BMSCs)have emerged as ideal seed cells for PNI treatment due to their strong differentiation potential and autologous trans-plantation ability.This review aims to summarize the molecular mechanisms by which BMSCs mediate nerve repair in PNI.The key mechanisms discussed include the differentiation of BMSCs into multiple types of nerve cells to promote repair of nerve injury.BMSCs also create a microenvironment suitable for neuronal survival and regeneration through the secretion of neurotrophic factors,extracellular matrix molecules,and adhesion molecules.Additionally,BMSCs release pro-angiogenic factors to promote the formation of new blood vessels.They modulate cytokine expression and regulate macrophage polarization,leading to immunomodulation.Furthermore,BMSCs synthesize and release proteins related to myelin sheath formation and axonal regeneration,thereby promoting neuronal repair and regeneration.Moreover,this review explores methods of applying BMSCs in PNI treatment,including direct cell trans-plantation into the injured neural tissue,implantation of BMSCs into nerve conduits providing support,and the application of genetically modified BMSCs,among others.These findings confirm the potential of BMSCs in treating PNI.However,with the development of this field,it is crucial to address issues related to BMSC therapy,including establishing standards for extracting,identifying,and cultivating BMSCs,as well as selecting application methods for BMSCs in PNI such as direct transplantation,tissue engineering,and genetic engineering.Addressing these issues will help translate current preclinical research results into clinical practice,providing new and effective treatment strategies for patients with PNI.

Effects of interleukin-10 treated macrophages on bone marrow mesenchymal stem cells via signal transducer and activator of transcription 3 pathway

BACKGROUND Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be solved.Regulating the various phenotypes of macrophages to enhance the inflammatory environment can significantly affect the progression of diseases and tissue engineering repair process.AIM To assess the influence of interleukin-10(IL-10)on the osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)following their interaction with macrophages in an inflammatory environment.METHODS IL-10 modulates the differentiation of peritoneal macrophages in Wistar rats in an inflammatory environment.In this study,we investigated its impact on the proliferation,migration,and osteogenesis of BMSCs.The expression levels of signal transducer and activator of transcription 3(STAT3)and its activated form,phos-phorylated-STAT3,were examined in IL-10-stimulated macrophages.Subsequently,a specific STAT3 signaling inhibitor was used to impede STAT3 signal activation to further investigate the role of STAT3 signaling.RESULTS IL-10-stimulated macrophages underwent polarization to the M2 type through substitution,and these M2 macrophages actively facilitated the osteogenic differentiation of BMSCs.Mechanistically,STAT3 signaling plays a crucial role in the process by which IL-10 influences macrophages.Specifically,IL-10 stimulated the activation of the STAT3 signaling pathway and reduced the macrophage inflammatory response,as evidenced by its diminished impact on the osteogenic differentiation of BMSCs.CONCLUSION Stimulating macrophages with IL-10 proved effective in improving the inflammatory environment and promoting the osteogenic differentiation of BMSCs.The IL-10/STAT3 signaling pathway has emerged as a key regulator in the macrophage-mediated control of BMSCs’osteogenic differentiation.

Potential plausible role of Wharton’s jelly mesenchymal stem cells for diabetic bone regeneration

This letter addresses the review titled“Wharton’s jelly mesenchymal stem cells:Future regenerative medicine for clinical applications in mitigation of radiation injury”.The review highlights the regenerative potential of Wharton’s jelly mesenchymal stem cells(WJ-MSCs)and describes why WJ-MSCs will become one of the most probable stem cells for future regenerative medicine.The potential plausible role of WJ-MSCs for diabetic bone regeneration should be noticeable,which will provide a new strategy for improving bone regeneration under diabetic conditions.

Bone-marrow mesenchymal stem cells reduce rat intestinal ischemia-reperfusion injury, ZO-1 downregulation and tight junction disruption via a TNF-α-regulated mechanism

AIM: To investigate the effect of bone-marrow mesenchymal stem cells (BM MSCs) on the intestinal mucosa barrier in ischemia/reperfusion (I/R) injury. METHODS: BM MSCs were isolated from male Sprague-Dawley rats by density gradient centrifugation, cultured, and analyzed by flow cytometry. I/R injury was induced by occlusion of the superior mesenteric artery for 30 min. Rats were treated with saline, BM MSCs (via intramucosal injection) or tumor necrosis factor (TNF)-α blocking antibodies (via the tail vein). I/R injury was assessed using transmission electron microscopy, hematoxylin and eosin (HE) staining, immunohistochemistry, western blotting and enzyme linked immunosorbent assay.RESULTS: Intestinal permeability increased, tight junctions (TJs) were disrupted, and zona occludens 1 (ZO-1) was downregulated after I/R injury. BM MSCs reduced intestinal mucosal barrier destruction, ZO-1 downregulation, and TJ disruption. The morphological abnormalities after intestinal I/R injury positively correlated with serum TNF-α levels. Administration of anti-TNF-α IgG or anti-TNF-α receptor 1 antibodies attenuated the intestinal ultrastructural changes, ZO-1 downregulation, and TJ disruption. CONCLUSION: Altered serum TNF-α levels play an important role in the ability of BM MSCs to protect against intestinal I/R injury.

Chinese preparation Xuesaitong promotes the mobilization of bone marrow mesenchymal stem cells in rats with cerebral infarction

After cerebral ischemia, bone marrow mesenchymal stem cells are mobilized and travel from the bone marrow through peripheral circulation to the focal point of ischemia to initiate tissue regeneration. However, the number of bone marrow mesenchymal stem cells mobilized into peripheral circulation is not enough to exert therapeutic effects, and the method by which blood circulation is promoted to remove blood stasis influences stem cell homing. The main ingredient of Xuesaitong capsules is Panax notoginseng saponins, and Xuesaitong is one of the main drugs used for promoting blood circulation and removing blood stasis. We established rat models of cerebral infarction by occlusion of the middle cerebral artery and then intragastrically administered Xuesaitong capsules（20, 40 and 60 mg/kg per day） for 28 successive days. Enzyme-linked immunosorbent assay showed that in rats with cerebral infarction, middle- and high-dose Xuesaitong significantly increased the level of stem cell factors and the number of CD117-positive cells in plasma and bone marrow and significantly decreased the number of CD54-and CD106-positive cells in plasma and bone marrow. The effect of low-dose Xuesaitong on these factors was not obvious. These findings demonstrate that middle- and high-dose Xuesaitong and hence Panax notoginseng saponins promote and increase the level and mobilization of bone marrow mesenchymal stem cells in peripheral blood.

Effect of bone marrow mesenchymal stem cells on the Smad expression of hepatic fibrosis rats

Objective:To investigate the impact of bone marrow mesenchymal stem cells on Smad expression of hepatic fibrosis rats.Methods:A total of 48 adult female SD rats were randomly divided into three groups,normal control group(n=10),observation group(n=19)with liver fibrosis model rats injected with BMSCs cells:model group(n=19),with liver fibrosis model rats injected with physiological saline.Serum index,TGF-β1 and Smad expression were detected.Results:TypeⅢprocollagen,Ⅳcollagen,hyaluronic acid,laminin levels of observation group were significantly lower than those of model group(P<0.05).The content and expression of TGF-β1in serum and liver tissue of observation group were significantly lower than those of model group(P<0.05).Compared with normal control group,the Smad3,Smad4 mRNA and protein expression of model group were significantly increased,the Smad7 mRNA and protein expression were significantly reduced(P<0.05).Compared with model group.Smad3,Smad4 mRNA and protein expression of observation group were significantly reduced,and Smad7 mRNA expression were significantly increased(P<0.05).Conclusions:BMSCs can regulate Smad expression to some extent,and reduce the degree of liver fibrosis.

Bone marrow-derived mesenchymal stem cells protect against experimental liver fibrosis in rats

AIM: Recent reports have shown the capacity of mesenchymal stem cells (MSCs) to differentiate into hepatocytes in vitro and in vivo. MSCs administration could repair injured liver, lung, or heart through reducing inflammation, collagen deposition, and remodeling. These results provide a clue to treatment of liver fibrosis. The aim of this study was to investigate the effect of infusion of bone marrow (BM)-derived MSCs on the experimental liver fibrosis in rats. METHODS: MSCs isolated from BM in male Fischer 344 rats were infused to female Wistar rats induced with carbon tetrachloride (CCI4) or dimethylnitrosamine (DMN). There were two random groups on the 42nd d of CCI4: CCl4/MSCs, to infuse a dose of MSCs alone; CCI4/saline, to infuse the same volume of saline as control. There were another three random groups after exposure to DMN: DMN10/MSCs, to infuse the same dose of MSCs on d 10; DMN10/saline, to infuse the same volume of saline on d 10; DMN20/MSCs, to infuse the same dose of MSCs on d 20. The morphological and behavioral changes of rats were monitored everyday. After 4-6 wk of MSCs administration, all rats were killed and fibrosis index were assessed by histopathology and radioimmunoassay. Smooth muscle alpha-actin (alpha-SMA) of liver were tested by immunohistochemistry and quantified by IBAS 2.5 software. Male rats sex determination region on the Y chromosome (sry) gene were explored by PCR. RESULTS: Compared to controls, infusion of MSCs reduced the mortality rates of incidence in CCl4-induced model (10% vs 20%) and in DMN-induced model (20-40% vs 90%).The amount of collagen deposition and alpha-SMA staining was about 40-50% lower in liver of rats with MSCs than that of rats without MSCs. The similar results were observed in fibrosis index. And the effect of the inhibition of fibrogenesis was greater in DMN10/MSCs than in DMN20/MSCs. The sry gene was positive in the liver of rats with MSCs treatment by PCR. CONCLUSION: MSCs treatment can protect against experimental liver fibrosis in CCMnduced or DMN-induced rats and the mechanisms of the anti-fibrosis by MSCs will be studied further.

Reversal of hyperglycemia in diabetic rats by portal vein transplantation of islet-like cells generated from bone marrow mesenchymal stem cells

AIM: To study the capacity of bone marrow mesenchymal stem cells (BM-MSCs) trans-differentiating into islet-like cells and to observe the effect of portal vein transplantation of islet-like cells in the treatment of streptozotocin-induced diabetic rat. METHODS: BM-MSCs were isolated from SD rats and induced to differentiate into islet-like cells under defined conditions. Differentiation was evaluated with electron microscopy, RT-PCR, immunofluorescence and flow cytometry. insulin release after glucose challenge was tested with ELiSA. Then allogeneic islet-like cells were transplanted into diabetic rats via portal vein. Blood glucose levels were monitored and islet hormones were detected in the liver and pancreas of the recipient by immunohistochemistry. RESULTS: BM-MSCs were spheroid adherent monolayers with high CD90, CD29 and very low CD45 expression. Typical islet-like cells clusters were formed after induction. Electron microscopy revealed that secretory granules were densely packed within the cytoplasm of the differentiated cells. The spheroid cells expressed islet related genes and hormones. The insulin-positive cells accounted for 19.8% and mean fluorescence intensity increased by 2.6 fold after induction. The cells secreted a small amount of insulin that was increased 1.5 fold after glucose challenge. After transplantation, islet-like cells could locate in the liver expressing islet hormones and lower the glucose levels of diabetic rats during d 6 to d 20.CONCLUSION: Rat BM-MSCs could be transdifferentiated into islet-like cells in vitro . Portal vein transplantation of islet-like cells could alleviate the hyperglycemia of diabetic rats.

Bone marrow-derived mesenchymal stem cells ameliorate sodium nitrite-induced hypoxic brain injury in a rat model

Sodium nitrite（Na NO2） is an inorganic salt used broadly in chemical industry. Na NO2 is highly reactive with hemoglobin causing hypoxia. Mesenchymal stem cells（MSCs） are capable of differentiating into a variety of tissue specific cells and MSC therapy is a potential method for improving brain functions. This work aims to investigate the possible therapeutic role of bone marrow-derived MSCs against Na NO2 induced hypoxic brain injury. Rats were divided into control group（treated for 3 or 6 weeks）, hypoxic（HP） group（subcutaneous injection of 35 mg/kg Na NO2 for 3 weeks to induce hypoxic brain injury）, HP recovery groups N-2 w R and N-3 w R（treated with the same dose of Na NO2 for 2 and 3 weeks respectively, followed by 4-week or 3-week self-recovery respectively）, and MSCs treated groups N-2 w SC and N-3 w SC（treated with the same dose of Na NO2 for 2 and 3 weeks respectively, followed by one injection of 2 × 106 MSCs via the tail vein in combination with 4 week self-recovery or intravenous injection of Na NO2 for 1 week in combination with 3 week self-recovery）. The levels of neurotransmitters（norepinephrine, dopamine, serotonin）, energy substances（adenosine monophosphate, adenosine diphosphate, adenosine triphosphate）, and oxidative stress markers（malondialdehyde, nitric oxide, 8-hydroxy-2′-deoxyguanosine, glutathione reduced form, and oxidized glutathione） in the frontal cortex and midbrain were measured using high performance liquid chromatography. At the same time, hematoxylin-eosin staining was performed to observe the pathological change of the injured brain tissue. Compared with HP group, pathological change of brain tissue was milder, the levels of malondialdehyde, nitric oxide, oxidized glutathione, 8-hydroxy-2′-deoxyguanosine, norepinephrine, serotonin, glutathione reduced form, and adenosine triphosphate in the frontal cortex and midbrain were significantly decreased, and glutathione reduced form/oxidized glutathione and adenosine monophosphate/adenosine triphosphate ratio were significantly increased in the MSCs treated groups. These findings suggest that bone marrow-derived MSCs exhibit neuroprotective effects against Na NO2-induced hypoxic brain injury through exerting anti-oxidative effects and providing energy to the brain.

Intravenous transplantation of bone marrow mesenchymal stem cells promotes neural regeneration after traumatic brain injury

To investigate the supplement of lost nerve cells in rats with traumatic brain injury by intravenous administration of allogenic bone marrow mesenchymal stem cells, this study established a Wistar rat model of traumatic brain injury by weight drop impact acceleration method and administered 3 × 106 rat bone marrow mesenchymal stem cells via the lateral tail vein. At 14 days after cell transplantation, bone marrow mesenchymal stem cells differentiated into neurons and astrocytes in injured rat cerebral cortex and rat neurological function was improved significantly. These findings suggest that intravenously administered bone marrow mesenchymal stem cells can promote nerve cell regeneration in injured cerebral cortex, which supplement the lost nerve cells.

Effect of Electromagnetic Fields on Proliferation and Differentiation of Cultured Mouse Bone Marrow Mesenchymal Stem Cells

Summary: In order to study the effects of electromagnetic fields (EMFs) on proliferation, differentiation and intercellular cyclic AMP (cAMP) in mouse bone marrow mesenchymal stem cells (MSCs) in vitro, the mouse bone MSCs were isolated and cultured in vitro. The third passage MSCs were divided into 4 groups and stimulated with EMFs. The cellular proliferation (MTT), the cellular differentiation (alkaline phosphatase activity, ALP), and the intercellular cAMP level were investigated at different time points. The results showed that EMF (50Hz pulse burst 2 mT peak) inhibited the cellular proliferation (P<0.05), enhanced the cellular differentiation (P<0.05), and increased the intercellular cAMP level (P<0.01) in the early time of the stimulation (1-3 days), but the intercellular cAMP level did not increased further in the later days. We are led to conclude that the cAMP may be involved in the mediation of the growth inhibitory and differentiation-inducing signals of specific EMFs in vitro.

Effects of lateral ventricular transplantation of bone marrow-derived mesenchymal stem cells modified with brain-derived neurotrophic factor gene on cognition in a rat model of Alzheimer's disease

In the present study, transplantation of bone marrow-derived mesenchymal stem cells modified with brain-derived neurotrophic factor gene into the lateral ventricle of a rat model of Alzheimer＇s disease, resulted in significant attenuation of nerve cell damage in the hippocampal CA1 region. Furthermore, brain-derived neurotrophic factor and tyrosine kinase B mRNA and protein levels were significantly increased, and learning and memory were significantly improved. Results indicate that transplantation of bone marrow-derived mesenchymal stem cells modified with brain-derived neurotrophic factor gene can significantly improve cognitive function in a rat model of Alzheimer＇s disease, possibly by increasing the levels of brain-derived neurotrophic factor and tyrosine kinase B in the hippocampus.