Mechanism of regulatory effect of recombinant human HMGB1 on endothelial cell angiogenesis / 器官移植

Objective To unravel the possible mechanism of the role of recombinant human high mobility group box 1 (rhHMGB1) protein in regulating the angiogenesis of endothelial cells. Methods Endothelial cells were divided into the control group, bone marrow mesenchymal stem cells (MSC) supernatant group and rhHMGB1 group. The proliferation and survival of endothelial cells were detected by cell counting kit(CCK)-8 assay. The relative expression levels of vascular endothelial growth factor (VEGF), Yes-associated protein (YAP), CD31 and hypoxia inducible factor (HIF)-1α proteins were determined by Western blot. The relative expression levels of VEGF, YAP, CD31 and HIF-1α messenger RNA (mRNA) were detected by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). The migration ability of endothelial cells was assessed by Transwell chamber test. The localization of YAP was detected by immunofluorescence staining. Results Compared with the control group, the migration rate of endothelial cells was increased in the rhHMGB1 group (P < 0.05), and the cell migration rate was enhanced over time. Compared with the control group, the relative expression levels of VEGF and p-YAP proteins were up-regulated in the MSC supernatant group, and the differences were statistically significant (both P < 0.05). Compared with the control group, the relative expression levels of VEGF and HIF-1α proteins, VEGF and CD31 mRNA and YAP and p-YAP proteins were up-regulated, and YAP/p-YAP ratio was increased in the rhHMGB1 group, and the differences were statistically significant (all P < 0.05). Compared with the MSC supernatant group, the relative expression levels of CD31 mRNA and YAP protein were up-regulated, and the YAP/p-YAP ratio was increased in the rhHMGB1 group, and the differences were statistically significant (all P < 0.05). Conclusions Exogenous high-concentration rhHMGB1 may promote the migration ability of endothelial cells and up-regulate the expression levels of angiogenesis-related proteins by regulating the recruitment of YAP to the nucleus.

Improvement effect and mechanism of N-butylphthalide on inflammatory injury of bone marrow mesenchymal stem cells in rats / 中国药房

OBJECTIVE To study the improvement effect and possible mechanism of N-butylphthalide on inflammatory injury of bone marrow mesenchymal stem cells （BMSCs） in rats. METHODS BMSCs of rats were divided into control group， model group， N-butylphthalide low-concentration， medium-concentration and high-concentration groups （10， 20， 50 μmol/L）. BMSCs were cultured in vitro and lipopolysaccharide （the final concentration of 10 mg/L） was used to establish the inflammatory injury model. After the intervention of N-butylphthalide， the survival rate， apoptotic rate， the contents of tumor necrosis factor α （TNF- α）， interleukin 1β （IL-1β） and IL-6 in cell culture medium， the mRNA expression of nuclear factor-κB（NF-κB） p65， and the protein expressions of caspase-3， B-cell lymphoma 2 （Bcl-2）， Bcl-2 related X protein （Bax） and NF-κB p65 in cells were detected. RESULTS Compared with control group， the survival rate and protein expression of Bcl-2 were decreased significantly in model group （P＜0.05）； the apoptotic rate， contents of TNF-α， IL-1β and IL-6， the mRNA expression of NF-κB p65， and the protein expressions of caspase-3， Bax and NF-κB p65 were increased significantly （P＜0.05）. Compared with model group， above indexes were significantly reversed in all concentration groups of N-butylphthalide （P＜0.05）， in concentration-dependent manner. CONCLUSIONS N-butylphthalide can ameliorate the inflammatory injury of BMSCs induced by lipopolysaccharide， and its mechanism may be related to the inhibition of NF-κB signaling pathway.

MicroRNA-22-3p Regulates the Expression of Kruppel-like Factor 6 to Affect the Cardiomyocyte-like Differentiation of Bone Marrow Mesenchymal Stem Cell / 中国医学科学院学报

Objective To explore the effect of microRNA-22-3p (miR-22-3p) regulating the expression of Kruppel-like factor 6 (KLF6) on the cardiomyocyte-like differentiation of bone marrow mesenchymal stem cell (BMSC). Methods Rat BMSC was isolated and cultured,and the third-generation BMSC was divided into a control group,a 5-azacytidine(5-AZA)group,a mimics-NC group,a miR-22-3p mimics group,a miR-22-3p mimics+pcDNA group,and a miR-22-3p mimics+pcDNA-KLF6 group.Real-time fluorescent quantitative PCR (qRT-PCR) was carried out to determine the expression of miR-22-3p and KLF6 in cells.Immunofluorescence staining was employed to detect the expression of Desmin,cardiac troponin T (cTnT),and connexin 43 (Cx43).Western blotting was employed to determine the protein levels of cTnT,Cx43,Desmin,and KLF6,and flow cytometry to detect the apoptosis of BMSC.The targeting relationship between miR-22-3p and KLF6 was analyzed by dual luciferase reporter gene assay. Results Compared with the control group,5-AZA up-regulated the expression of miR-22-3p (q=7.971,P<0.001),Desmin (q=7.876,P<0.001),cTnT (q=10.272,P<0.001),and Cx43 (q=6.256,P<0.001),increased the apoptosis rate of BMSC (q=12.708,P<0.001),and down-regulated the mRNA (q=20.850,P<0.001) and protein (q=11.080,P<0.001) levels of KLF6.Compared with the 5-AZA group and the mimics-NC group,miR-22-3p mimics up-regulated the expression of miR-22-3p (q=3.591,P<0.001;q=11.650,P<0.001),Desmin (q=5.975,P<0.001;q=13.579,P<0.001),cTnT (q=7.133,P<0.001;q=17.548,P<0.001),and Cx43 (q=4.571,P=0.037;q=11.068,P<0.001),and down-regulated the mRNA (q=7.384,P<0.001;q=28.234,P<0.001) and protein (q=4.594,P=0.036;q=15.945,P<0.001) levels of KLF6.The apoptosis rate of miR-22-3p mimics group was lower than that of 5-AZA group (q=8.216,P<0.001).Compared with the miR-22-3p mimics+pcDNA group,miR-22-3p mimics+pcDNA-KLF6 up-regulated the mRNA(q=23.891,P<0.001) and protein(q=13.378,P<0.001)levels of KLF6,down-regulated the expression of Desmin (q=9.505,P<0.001),cTnT (q=10.985,P<0.001),and Cx43 (q=8.301,P<0.001),and increased the apoptosis rate (q=4.713,P=0.029).The dual luciferase reporter gene experiment demonstrated that KLF6 was a potential target gene of miR-22-3p. Conclusion MiR-22-3p promotes cardiomyocyte-like differentiation of BMSC by inhibiting the expression of KLF6.

Effect of PKM2 on Osteogenic and Adipogenic Differentiation of Bone Marrow Mesenchymal Stem Cells in Myeloma Bone Disease / 中国实验血液学杂志

OBJECTIVE@#To investigate the expression of pyruvate kinase M2 (PKM2) in bone marrow mesenchymal stem cells (BMSCs) in myeloma bone disease (MBD) and its effect on osteogenic and adipogenic differentiation of BMSCs.@*METHODS@#BMSCs were isolated from bone marrow of five patients with multiple myeloma (MM) (MM group) and five with iron deficiency anemia (control group) for culture and identification. The expression of PKM2 protein were compared between the two groups. The differences between osteogenic and adipogenic differentiation of BMSCs were assessed by using alkaline phosphatase (ALP) and oil red O staining, and detecting marker genes of osteogenesis and adipogenesis. The effect of MM cell line (RPMI-8226) and BMSCs co-culture on the expression of PKM2 was explored. Functional analysis was performed to investigate the correlations of PKM2 expression of MM-derived BMSCs with osteogenic and adipogenic differentiation by employing PKM2 activator and inhibitor. The role of orlistat was explored in regulating PKM2 expression, osteogenic and adipogenic differentiation of MM-derived BMSCs.@*RESULTS@#Compared with control, MM-originated BMSCs possessed the ability of increased adipogenic and decreased osteogenic differentiation, and higher level of PKM2 protein. Co-culture of MM cells with BMSCs markedly up-regulated the expression of PKM2 of BMSCs. Up-regulation of PKM2 expression could promote adipogenic differentiation and inhibit osteogenic differentiation of MM-derived BMSCs, while down-regulation of PKM2 showed opposite effect. Orlistat significantly promoted osteogenic differentiation in MM-derived BMSCs via inhibiting the expression of PKM2.@*CONCLUSION@#The overexpression of PKM2 can induce the inhibition of osteogenic differentiation of BMSCs in MBD. Orlistat can promote the osteogenic differentiation of BMSCs via inhibiting the expression of PKM2, indicating a potential novel agent of anti-MBD therapy.

Bone marrow mesenchymal stem cells exosome miR-126-3p targets CCR1 to inhibit the malignant proliferation and metastasis of non-small cell lung cancer cells / 西安交通大学学报(医学版)

【Objective】 To investigate the effects of miR-126-3p targeting chemokine receptor 1 (CCR1) in exosomes derived from bone marrow mesenchymal stem cells (BMSC) on the proliferation, migration, and invasion of lung cancer cells. 【Methods】 BMSC cells were cultured; exosomes were extracted and identified by the exosomal marker proteins CD63 and TSG101. After exosome culture of A549 cells for different durations (0, 24, 48, and 72 h), cell survival rate was detected by CCK-8, mRNA levels of miR-126-3p and CCR1 were detected by qRT-PCR, and cell migration and invasion abilities were detected by Transwell assay. The relative expressions of CCR1, epithelial cadherin (E-cad), neural cadherin (N-cadherin), and Vimentin were detected by Western blotting. 【Results】 Exosomes had round or oval cup-shaped structures with bright edges and dark middle, with a particle size distribution of about 152 nm, expressing CD63 and TSG101 proteins. The expression of miR-126-3p in exosomes was higher than that in A549 cells. The expression of miR-126-3p was low in A549 cells and that of CCR1 mRNA was high. However, after co-culture with exosomes, the expression of miR-126-3p in A549 cells was increased, while the expression of CCR1 was decreased. A549 cells were cocultured with exosomes for 0, 24, 48, and 72 h. The survival rate, migration and invasion abilities, CCR1 gene and protein expression levels, and N-cad and Vimentin protein expression levels of A549 cells decreased gradually with the extension of culture time. The level of miR-126-3p and the expression of E-cad protein increased gradually with the extension of culture time. 【Conclusion】 The co-culture of exosomes derived from bone marrow mesenchymal stem cells with A549 cells can increase the expression level of miR-126-3p, and miR-126-3p can reduce the proliferation, migration, and invasion of A549 cells by targeting the inhibition of CCR1 expression.

Bone marrow mesenchymal stem cell-derived exosomes promote microglia/macrophage M2 polarization in acute cerebral ischemia rats and inhibit inflammatory response / 中国药科大学学报

@#The aim of the present study was to investigate the effects of exosomes derived from bone marrow mesenchymal stem cells (BMSCs) on the polarization of M1/M2 microglia/macrophages in rats with acute cerebral ischemia.Ultrahigh-speed centrifugation was employed to isolate and identify exosomes; a middle cerebral artery occlusion (MCAO) model was prepared in rats using the intraluminal filament technique; Longa scoring and corner tests were used to evaluate the neurological function of rats; 2, 3, 5-triphenyltetrazole chloride (TTC) staining was used to assess the infarct volume in rat brains; immunofluorescence double-labeling of CD16/32/Iba1 and CD206/Iba1 was performed to detect M1/M2 phenotypes of microglia/macrophages; RT-qPCR was employed to measure the mRNA expression of CD86, inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α), arginase-1 (Arg-1), interleukin-10 (IL-10), and transforming growth factor beta (TGF-β) in the ischemic penumbra of rat brains.The experimental results showed that BMSC-Exos reduced the number of CD16/32+/Iba1+ positive cells in the ischemic penumbra (P < 0.01) while increasing the number of CD206+/Iba1+positive cells (P < 0.01), and decreased the mRNA expression of iNOS, CD86, and TNF-α, while increasing the mRNA expression of Arg-1, TGF-β, and IL-10 (P < 0.05 or P < 0.01).This research suggests that BMSC-Exos can regulate M1/M2 polarization of microglia/macrophages in rats with acute cerebral ischemia, alleviate neuroinflammation, and improve ischemic brain injury.

The pivotal role of autophagy in bone cells:bone-related cell activity and bone metabolism / 中国组织工程研究

BACKGROUND:The importance of autophagy for maintaining cellular homeostasis and stress response has long been recognized.As a way for cells to selectively clear their damaged organelles to achieve the recycling of cellular components,autophagy has a pivotal role in bone metabolism.OBJECTIVE:To review the role and possible mechanisms of autophagy in regulating bone-related cell activity and function among bone marrow mesenchymal stem cells,osteoblasts,osteocytes,and osteoclasts.METHODS:PubMed was searched for studies related to autophagy using the keywords of "autophagy;bone marrow mesenchymal stem cells;osteoblasts;osteocytes;osteoclasts."RESULTS AND CONCLUSION:We finally included 84 papers.Autophagy plays an important role in bone metabolism.Autophagy is involved in maintaining the balance between mineralization and absorption,and then maintaining bone homeostasis.An appropriate autophagy inducer may also benefit bone remodeling.Abnormal autophagy can lead to disorders of bone balance,leading to diseases such as osteoporosis.We may prevent or treat bone-related diseases by regulating the level of autophagy as its function in maintaining the balance of mineralization and resorption in bone homeostasis.

Bone marrow mesenchymal stem cells attenuate pyroptosis lipopolysaccharide-induced renal injury rats / 中华危重病急救医学

Objective:To investigate the effect and mechanism of bone marrow mesenchymal stem cell (BMSC) on pyroptosis of rats with kidney injury.Methods:Bone marrow of 4-5 week-old female Sprague-Dawley (SD) rats was isolated in vitro and BMSC was obtained. The third generations of BMSC were used to further experiments. Fifteen 6 week-old SD rats were cluster-randomized divided into control group, kidney injury group and BMSC group (5 rats in each group). Rats in kidney injury group were injected with lipopolysaccharide (LPS) 1 mg/kg via tail vein; the control group was given the same amount of normal saline. BMSC group was injected with 0.5 mL BMSC (including 2×10 6 BMSC) via tail vein after modeling; the kidney injury group received the same amount of normal saline. On day 3 after these injections, serum creatinine (SCr) was detected by picric acid method, and blood urea nitrogen (BUN) was detected by diacetyl monoxime. The levels of cystatin C (Cys C), interleukins (IL-1β and IL-18) in blood were detected by enzyme-linked immunosorbent assay (ELISA). The rats were then sacrificed and their kidneys were removed for subsequent detection. The mRNA expression levels of NOD-like receptor protein 3 (NLRP3) and cysteinyl aspartate-specific protease-1 (caspase-1) of kidney were detected by quantificational real-time quantitative polymerase chain reaction (qRT-PCR). The protein expression levels of NLRP3 and caspase-1 of kidney were detected by Western blotting. Results:In vitro, after bone marrow cell suspension was cultured for 24 hours, a large number of round adherent cells and suspended cells appeared in each culture flask. After 4-5 days of culture, a large number of long spindle cells adhered to the wall, and there were still obvious impurity cells. After trypsin digestion and passage to the third generation, the long spindle adherent cells grew mainly in the culture flask and were basically purified as BMSC. In vivo, compared with the control group, the levels of SCr, BUN, Cys C, IL-1β and IL-18 in kidney injury group were increased [SCr (μmol/L): 85.22±2.29 vs. 21.80±0.59, BUN (mmol/L): 11.50±0.64 vs. 5.86±0.83, Cys C (mg/L): 0.13±0.01 vs. 0.11±0.02, IL-1β (ng/L): 31.49±1.42 vs. 4.74±0.49, IL-18 (ng/L): 29.01±1.95 vs. 1.52±0.03, all P < 0.05]. The mRNA and protein expression levels of NLRP3, caspase-1 were significantly increased [NLRP3 mRNA (2 -ΔΔCt): 3.635±0.296 vs. 1.000±0.002, caspase-1 mRNA (2 -ΔΔCt): 4.020±0.228 vs. 1.001±0.003; NLRP3 protein (NLRP3/β-actin): 1.560±0.868 vs. 0.902±0.036, caspase-1 protein (caspase-1/β-actin): 1.392±0.097 vs. 0.895±0.046, all P < 0.05]. Compared with kidney injury group, the levels of SCr, BUN, IL-1β and IL-18 in BMSC group were significantly decreased [SCr (μmol/L): 51.64±3.84 vs. 85.22±2.29, BUN (mmol/L): 9.90±0.46 vs. 11.50±0.64, IL-1β (ng/L): 24.20±1.45 vs. 31.49±1.42, IL-18 (ng/L): 12.97±1.25 vs. 29.01±1.95, all P < 0.05]. The mRNA and protein expression levels of NLRP3, caspase-1 were significantly decreased [NLRP3 mRNA (2 -ΔΔCt): 1.488±0.136 vs. 3.635±0.296, caspase-1 mRNA (2 -ΔΔCt): 1.643±0.143 vs. 4.020±0.228; NLRP3 protein (NLRP3/β-actin): 1.227±0.053 vs. 1.560±0.868, caspase-1 protein (caspase-1/β-actin): 1.159±0.107 vs. 1.392±0.097, all P < 0.05]. Conclusion:In vivo, BMSC may attenuate pyroptosis in LPS-induced kidney injury rats.

Effect and Mechanism of Cxcr4 Gene-Modified BMSC-Derived Exosomes on Aplastic Anemia / 中国实验血液学杂志

OBJECTIVE@#To explore the improvement effect of CXC chemokine receptor 4 (Cxcr4) gene-modified bone marrow mesenchymal stem cell (BMSC)-derived exosomes on aplastic anemia (AA), and make a preliminary exploration of the mechanism.@*METHODS@#Mouse BMSCs were isolated and cultured, then infected by recombinant lentivirus carrying Cxcr4 gene. The expression of green fluorescence was observed through fluorescence microscope, the expression of Cxcr4 mRNA was detected by real-time fluorescence quantitative PCR, and the BMSC-derived exosomes modified with Cxcr4 gene were extracted. Mouse models of AA were constructed, and control group, model group (AA), AA+BMSC group, AA+NC-BMSC group, AA+Cxcr4-BMSC group were set up. Except control group and model group, the other three groups of mice were injected 400 μl exosomes from different sources via the tail vein, after 2 weeks, the routine blood indices and the number of bone marrow nucleated cells were detected, the pathological changes of bone marrow were observed by HE staining, and the expression level of Treg cells was detected by flow cytometry.@*RESULTS@#Mouse BMSCs were successfully isolated, and BMSCs with high expression of Cxcr4 and their exosomes were obtained. Compared with the control group, the number of red blood cell (RBC), white blood cell (WBC), and platelet (PLT), the hemoglobin (Hb) content and proportion of Treg cells in the peripheral blood of mice in the model group significantly decreased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01). The proliferation level of nucleated cells was low, and the medullary cavity was filled with a large number of fat cells. Compared with the model group, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+BMSC group, AA+NC-BMSC group, and AA+Cxcr4-BMSC group significantly increased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01), and pathological changes of bone marrow were improved. In addition, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+Cxcr4-BMSC group were significantly higher than those in the AA+BMSC group (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01).@*CONCLUSION@#Injection of Cxcr4 gene-modified BMSC-derived exosomes has a certain improvement effect on AA mice, and the mechanism may be related to an increase of the proportion of Treg cells.

Mechanism of compound Fufangteng mixture-containing serum in promoting proliferation of bone marrow mesenchymal stem cell / 器官移植

Objective To investigate the effect of compound Fufangteng mixture-containing serum on the proliferation of bone marrow mesenchymal stem cell (BMSC) and its mechanism. Methods Rat BMSC were isolated, cultured and purified in vitro by direct adherence method. Cell morphology was observed. Surface markers were identified by flow cytometry. The rats were treated with compound Fufangteng mixture at a dose of 3 mL/(kg·d) by gavage for 14 d, and then the drug-containing serum was collected. BMSC were divided into the blank control group, drug-containing serum group, Notch1 small interfering ribonucleic acid (siRNA) group and Notch1 siRNA+drug-containing serum group. The proliferation rate of BMSC was detected and the relative expression levels of Notch1 signaling pathway-associated messenger ribonucleic acid (mRNA) and proteins were measured in each group. Results Microscopic observation showed that the first generation BMSC were seen in the long spindle shape, and grown in the parallel or spiral pattern. The third generation BMSC positively expressed CD90 and CD44, whereas were negative for CD45. Compared with the blank control group, the proliferation rate of BMSC in the drug-containing serum group and Notch1 siRNA+ drug-containing serum group was significantly increased, whereas that of BMSC was significantly decreased in the Notch1 siRNA group (all P < 0.05). Compared with the Notch1 siRNA group, the proliferation rate of BMSC was significantly increased in the Notch1 siRNA+drug-containing serum group (P < 0.05). Compared with the blank control group, the relative expression levels of Hey1 and Delta-like ligand (DLL)1 mRNA and proteins were significantly up-regulated in the drug-containing serum group, whereas those were significantly down-regulated in the Notch1 siRNA group and Notch1 siRNA+drug-containing serum group (all P < 0.05). Compared with the Notch1 siRNA group, the relative expression levels of Hey1 and DLL1 mRNA and proteins were significantly up-regulated in the Notch1 siRNA+drug-containing serum group (all P < 0.05). Conclusions Compound Fufangteng mixture-containing serum may promote the proliferation of rat BMSC, and its mechanism is probably associated with the activation of Notch1 signaling pathway.

In vitro maturation medium supplementation: utilization of repaglinide, L-carnitine, and mesenchymal stem cell-conditioned medium to improve developmental competence of oocytes derived from endometriosis mouse models

Endometriosis (EMS) is one of the most prevalent causes for female infertility. Herein, we investigated the effect of the repaglinide (RG), L-carnitine (LC), and bone marrow mesenchymal stem cell-conditioned medium (BMSC-CM) supplementation during in vitro maturation (IVM) on the quality, maturation, and fertilization rates, as well as embryonic quality and development of oocytes derived from normal and EMS mouse model. Immature oocytes were collected from two groups of normal and EMS-induced female NMRI mice at 6-8 weeks of age. Oocytes were cultured in IVM medium unsupplemented (control group), or supplemented with 1 M RG, 0.3 and 0.6 mg/mL LC, and 25 and 50% BMSC-CM. After 24 h of oocyte incubation, IVM rate and antioxidant status were assessed. Subsequently, the rates of fertilization, cleavage, blastulation, and embryonic development were assessed. Our results demonstrated that supplementation of IVM medium with LC and BMSC-CM, especially 50% BMSC-CM, significantly enhanced IVM and fertilization rates, and markedly improved blastocyst development and total blastocyst cell numbers in EMS-induced mice compared to the control group (53.28±0.24 vs 18.09±0.10%). Additionally, LC and BMSC-CM were able to significantly modulate EMS-induced nitro-oxidative stress by boosting total antioxidant capacity (TAC) and mitigating nitric oxide (NO) levels. Collectively, LC and BMSC-CM supplementation improved oocyte quality and IVM rates, pre-implantation developmental competence of oocytes after in vitro fertilization, and enhanced total blastocyst cell numbers probably by attenuating nitro-oxidative stress and accelerating nuclear maturation of oocytes. These outcomes may provide novel approaches to refining the IVM conditions that can advance the efficiency of assisted reproductive technologies in infertile couples.

Preliminary study of effect of erythropoietin pretreatment on enhancing directional homing ability of bone marrow mesenchymal stem cells in rats / 器官移植

Objective To evaluate the effect of erythropoietin (EPO) on the proliferation and migration of bone marrow mesenchymal stem cell (BMSC) in rats. Methods The 5th generation BMSCs were divided into the control (without EPO) and 10, 100, 500, 1 000 IU/mL EPO groups. After 24 h and 48 h of culture, the proliferation rate, migration ability and the expression levels of CXCR4 of BMSCs were detected in each group. The 5th generation BMSCs were further divided into BMSC and EPO-BMSC groups. After 48 h of culture, the effect of EPO upon surface markers, directional differentiation and cytoskeleton morphology of BMSCs were evaluated in both groups. Results After theco-culture of EPO and BMSCs for 48 h, the proliferation rate and migration ability of BMSCs were significantly enhanced, and the expression level of CXCR4 protein was significantly up-regulated in the 100 IU/mL and 500 IU/mL EPO groups compared with those in the control group (all P < 0.05). However, EPO exerted no effect upon the expression levels of surface markers and directional differentiation ability of BMSCs in the EPO-BMSC group. In the EPO-BMSC group, the fibrous skeleton of most BMSCs was arranged along the long axis in parallel. Conclusions EPO can improve the proliferation rate, migration ability and tissue repair capability of BMSCs, probably by promoting the directional homing of BMSCs to injured organs and tissues via up-regulating the expression level of CXCR4.

Effect of bone marrow mesenchymal stem cell on the expression of IL-10 and TNF-α in mice with ischemia-reperfusion acute kidney injury / 器官移植

Objective To evaluate the effect of bone marrow mesenchymal stem cell (BMSC) on the expression of interleukin (IL)-10 and tumor necrosis factor (TNF)-α in mice with ischemia-reperfusion acute kidney injury (IR-AKI). Methods All mice were randomly divided into the sham operation group (control group), ischemia-reperfusion injury group (IRI group) and BMSC treatment group (BMSC group), with 6 mice in each group, respectively. The renal function and pathological changes of mice were detected. The cell apoptosis of renal tissues of mice was determined. The expression levels of serum IL-10 and TNF-α of mice were quantitatively measured. The mouse BMSC was randomly divided into the control and hypoxia-reoxygenation groups (IRI group), and the expression levels of IL-10 and TNF-α in cell supernatant were determined. Results The renal structure of mice was normal in the control group, severe damage was observed in the IRI group, and mild damage occurred in the BMSC group. Compared with the control group, the renal tissue injury scores were significantly higher in the IRI and BMSC groups (both P < 0.05). Compared with the IRI group, the renal tissue injury score was significantly lower in the BMSC group (P < 0.05). Compared with the control group, the levels of serum creatinine (Scr) and blood urea nitrogen (BUN) were remarkably up-regulated in the IRI group, and the level of BUN was significantly up-regulated in the BMSC group (all P < 0.05). Compared with the IRI group, the levels of Scr and BUN were significantly down-regulated in the BMSC group (both P < 0.05). In the IRI group, the quantity of apoptotic cells in the renal tissues was considerably higher than those in the BMSC and control groups, and the quantity of apoptotic cells in the BMSC group was significantly higher than that in the control group (all P < 0.05). Compared with the control group, the levels of serum IL-10 and TNF-α were significantly up-regulated in the IRI group, whereas the level of serum TNF-α was significantly down-regulated and the level of serum IL-10 was significantly up-regulated in the BMSC group (all P < 0.05). Compared with the IRI group, the levels of serum IL-10 and TNF-α were significantly down-regulated in the BMSC group (both P < 0.05). The levels of IL-10 and TNF-α in the cell supernatant did not significantly differ between the IRI and control groups (P=0.080、0.627). Conclusions BMSC infusion may reduce the incidence of renal IRI and inflammation, probably via the mechanism of down-regulating TNF-α expression rather than up-regulating IL-10 expression.

Biocompatibility and effect on bone formation of a native acellular porcine pericardium: Results of in vitro and in vivo / 北京大学学报(医学版)

OBJECTIVE@#To examine the morphology and biocompatibility of a native acellular porcine pericardium (APP) in vitro and to evaluate its barrier function and effects on osteogenesis when used in guided bone regeneration (GBR) in vivo.@*METHODS@#First, the morphology of APP (BonanGenⓇ) was detected using a scanning electron microscope (SEM). Next, for biocompatibility test, proliferation of human bone marrow mesenchymal stem cells (hBMSCs) were determined using cell counting kit-8 (CCK-8) after being seeded 1, 3 and 7 days. Meanwhile, the cells stained with phalloidine and 4, 6-diamidino-2-phenylindole (DAPI) were observed using a confocal laser scanning microscopy (CLSM) to view the morphology of cell adhesion and pattern of cell proliferation on day 5. A 3-Beagle dog model with 18 teeth extraction sockets was used for the further research in vivo. These sites were randomly treated by 3 patterns below: filled with Bio-OssⓇand coverd by APP membrane (APP group), filled with Bio-OssⓇand covered by Bio-GideⓇmembrane (BG group) and natural healing (blank group). Micro-CT and hematoxylin-eosin (HE) were performed after 4 and 12 weeks.@*RESULTS@#A bilayer and three-dimensional porous ultrastructure was identified for APP through SEM. In vitro, APP facilitated proliferation and adhesion of hBMSCs, especially after 7 days (P < 0.05). In vivo, for the analysis of the whole socket healing, no distinct difference of new bone ratio was found between all the three groups after 4 weeks (P>0.05), however significantly more new bone regeneration was detected in APP group and BG group in comparison to blank group after 12 weeks (P < 0.05). The radio of bone formation below the membrane was significantly higher in APP group and BG group than blank group after 4 and 12 weeks (P < 0.05), however, the difference between APP group and BG group was merely significant in 12 weeks (P < 0.05). Besides, less resorption of buccal crest after 4 weeks and 12 weeks was observed in APP group of a significant difference compared in blank group (P < 0.05). The resorption in BG group was slightly lower than blank group (P>0.05).@*CONCLUSION@#APP showed considerable biocompatibility and three-dimentional structure. Performing well as a barrier membrane in the dog alveolar ridge preservation model, APP significantly promoted bone regeneration below it and reduced buccal crest resorption. On the basis of this study, APP is a potential osteoconductive and osteoinductive biomaterial.

MicroRNA-141 is regulated by serum of velvet antler to promote the proliferation of bone marrow mesenchymal stem cells in dexamethasone-induced cell model / 中国组织工程研究

BACKGROUND: The proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) can delay the procession of steroid-induced femoral head necrosis. Besides, microRNA-141 (miR-141) is one of the important regulatory factors to promote cell proliferation. In addition, velvet antler is a traditional Chinese medicine which has significant roles in repairing bone and tissue and improving health. OBJECTIVE: To investigate whether velvet antler serum can regulate the expression of miR-141 to promote the proliferation of BMSCs, and further delay or reverse the progression of steroid-induced femoral head necrosis. METHODS: BMSCs were isolated and cultured from Sprague-Dawley rats. The passage 3 BMSCs were transfected with miR-141 mimic or miR-141 inhibitors, and then real-time PCR and methyl thiazolyl tetrazolium (MTT) assay were performed for detecting miR-141 expression and cell proliferation, respectively. The passage 3 BMSCs were divided into three groups: control group (α-MEM), dexamethasone group (α-MEM+1 μmol/L dexamethasone), and velvet antler serum group (α-MEM+1 μmol/L dexamethasone+15% velvet antler serum). Expression of miR-141 mRNA was detected by real-time PCR at 24 hours after intervention. The proliferation ability of BMSCs was evaluated by MTT assay at 24, 48, and 72 hours after intervention. RESULTS AND CONCLUSION: After transfection with miR-141 mimic, the expression of miR-141 mRNA was upregulated, while the cell proliferation was reduced. After transfection with miR-141 inhibitor, the expression of miR-141 mRNA was downregulated, while the cell proliferation was increased. The expression of miR-141 mRNA was significantly higher in the dexamethasone group than the control group (P < 0.01), while the treatment with velvet antler serum could significantly downregulate the expression of miR-141 mRNA (P < 0.01). The absorbance of BMSCs in the dexamethasone group was significantly lower than that in the control group (P < 0.01), and the absorbance value in the velvet antler serum group was significantly higher than that in the dexamethasone group (P < 0.01). In conclusion, the serum containing velvet antler can downregulate the expression of miR-141 which is upregulated by dexamethasone and then do help to promote the proliferation of BMSCs.

Molecular mechanism of icariin in the treatment of bone nonunion / 中国组织工程研究

BACKGROUND: Nonunion is a common clinical complication in orthopedics, which seriously impacts the physical and mental health and quality of life of patients. In recent years, a large number of studies have found that icariin plays a significant role in promoting fracture healing and treating bone defects. Bone nonunion and fracture healing coexist, and the research on the mechanism of fracture healing actually focuses on the treatment of bone nonunion. OBJECTIVE: To review the research progress in the molecular mechanism of icariin in the treatment of bone nonunion. METHODS: The first author used “icariin, bone nonunion, bone marrow mesenchymal stem cells, periosteal cell, osteoblasts, osteoclast” as key words in English and Chinese to search PubMed, CNKI, WanFang and VIP databases. A total of 542 articles were retrieved and screened manually according to the selection criteria and exclusion criteria. Finally, 44 articles were included for result analysis. RESULTS AND CONCLUSION: Icariin can effectively promote fracture healing and treat bone nonunion by promoting the proliferation and differentiation of bone marrow mesenchymal stem cells and periosteal cells, promoting the proliferation and maturation of osteoblasts and inhibiting the osteoclast effect of osteoclasts. However, most of the experiments are still in the basic experimental research, and there is still a need for a large number of clinical studies as well as studies on related proteins and genes, to provide a new idea for the clinical use of Chinese herbs in the treatment of bone nonunion.

LncRNA Xist Promotes Proliferation and Migration of Rat BMSC by Regulating CXCR4 Expression / 中山大学学报(医学科学版)

@#【Objective】To explore the role of lncRNA Xist in proliferation and migration of rat bone marrow mesenchymal stem cells（BMSC）and its possible mechanism.【Methods】BMSC were isolated，cultured and identified from the femur and tibia of 3 weeks old SD female rats in vitro. SiRNAs was designed and screened to acquire a high silencing efficiency siRNA. Lipo2000 was used to transfected si- Xist and si- NC into BMSC of the experimental group（si- Xist group）and the control group（si-NC group）. BMSC proliferation capacity was determined by CCK-8 assay. The transverse and longitudinal mobility of BMSC were measured by wound healing assay and transwell migration assays. QPCR was performed to verify the silencing efficiency of lncRNA Xist and detect the expression levels of SDF- 1 and CXCR4 mRNA. Western blot was used to quantify the expression of CXCR4 protein.【Results】The P3 generation BMSC shows shuttle- like or whirlpool-like，and flow cytometry showed CD11b（-），CD34（-），CD45（-），CD44（+），CD90（+），CD105（+）. When siRNAs were used to interfere with the expression of lncRNA Xist in BMSC ，the silencing efficiency of three siRNAs was 67.92% ，68.72% and 98.32% ，respectively. CCK- 8 assay showed that the OD450 value of si- Xist group decreased compared with si-NC group at 24 h and 48 h（P < 0.001，P < 0.01，respectively）and had no statistical difference at 12 h（P > 0.05）. Wound healing assay showed that the wound healing percentage of si-Xist group was lower than that of si-NC group（P < 0.05）；and the transwell migration assay showed that，compared with si- NC group，the cells that migrated through the polycarbonate membrane were obviously decreased at 6 h（P < 0.001）. QPCR experiment showed that CXCR4 expression in si-Xist group was lower than that in si-NC group at mRNA level（P < 0.05），while SDF-1 expression showed no significant statistical difference（P > 0.05）. Western blotting confirmed that CXCR4 expression in si- Xist group was lower than that in si-NC group（P < 0.05）.【Conclusions】LncRNA Xist promotes proliferation and migration of rat BMSC by regulating CXCR4 expression.

Inhibition of macrophage signaling pathway by bone marrow mesenchymal stem cells (BMSC) and alleviation of pulmonary alveolitis in mice exposed to silica dust / 上海预防医学

Objective To study the mechanism of bone marrow mesenchymal stem cell (BMSC)-mediated alleviation of pulmonary alveolitis in mice exposed to silica dust. Methods Thirty mice were randomly divided into 3 groups:control group, and two silica groups with or without BMSCs transplantation.Through the tracheal tube clearance, mice in control group received a single injection 20.0 μL of 0.90% sodium chloride solution by one time.Mice from in silica group and silica/BMSCs transplantation group first received a single injection of 20.0 μL silica dust suspension (mass concentration 250 g/L); followed by either 500.0 μL of 0.90% sodium chloride solution or by 500.0 μL of BMSCs suspension (cell density 1×109/L) through tail vein infusion 6 hours later.Mice were euthanized on the 3th day of the experiments.The levels of NALP3 inflammasome in lungs was determined by Western blot.Transwell system was used for co-culture of BMDM (in upper-chamber) and BMSC (in lower-chamber) co-culture.The level of cytokines IL-1β in BMDM cultural supernatant was detected by enzyme linked immunosorbent assay after stimulated by SiO2 stimulation.The levels of NALP3 inflammasome of in BMDM was determined by Western blot. Results The levels of pro-IL-1β, IL-1β, pro-caspase-1, caspase-1 in lungs of silica/BMSCs transplantation group were lower than that in silica group (P < 0.01).In the experiment in vitro, the concentrations of IL-1β in SiO2 exposed BMSC/BMDM co-culture group were lower than the SiO2 exposure only groups (P < 0.05).Meanwhile, the levels of pro-IL-1β, IL-1β, pro-caspase-1, caspase-1 in BMDM was lower than that in silica group (P < 0.01).The level of these proteins didn′t change while when the cell-free supernatant of BMSC culture was directly added. Conclusion The BMSC could inhibit NALP3 inflammasome of macrophages stimulated by SiO2.

Protective Effect of Astragulus Polysaccharide on Chromosome Damage in Human BMSCs Exposed to Formaldehyde / 中国实验方剂学杂志

Objective::To study the protective effect of astragalus polysaccharide (APS) on micronucleus and sister chromatid exchange (SCE) in human bone marrow mesenchyml stem cell (BMSCs) exposed to formaldehyde, in order to initially explore the potential mechanism. Method::BMSCs were cultured in vitro, cells were randomly divided into five groups: control group, formaldehyde group, and APS 40, 100, 400 mg·L-1 groups. BMSCs were infected with 120 μmol·L-1 formaldehyde, meanwhile, APS 40, 100, 400 mg·L-1 groups were co-cultured with 40, 100, 400 mg·L-1 APS. Cell morphology was observed by inverted phase contrast microscope, micronucleus were detected by micronucleus test, SCE was detected by SCE test, and mRNA and protein expressions of proliferating cell nuclear antigen (PCNA), xeroderma pigmentosum B, D, F, G (XPB, XPD, XPF, XPG) were detected by quantitative real-time fluorescence polymerase chain reaction(Real-time PCR)and Western blot. Result::Compared with control group, cell counts decreased, and cell morphology of BMSCs in formaldehyde group significantly changed, they were all recovered gradually in 40, 100, 400 mg·L-1 APS groups. Compared with control group, the micronucleus and SCE increased significantly (P<0.01), PCNA mRNA and protein expressions down-regulated significantly (P<0.05), while XPB, XPD, XPF, XPG mRNA and protein expressions up-regulated significantly (P<0.05, P<0.01). Compared with formaldehyde group, BMSCs were treated with APS at 40, 100, 400 mg·L-1, micronucleus and SCE decreased significantly (P<0.01), and mRNA and protein expressions of PCNA, XPB, XPD, XPF and XPG up-regulated significantly (P<0.05, P<0.01). Among them, the 100 mg·L-1 APS group had the most obvious effect. Conclusion::APS can protect formaldehyde-induced BMSCs micronucleus and SCE, especially 100 mg·L-1 APS has the most obvious effect. The mechanism may be associated with the up-regulation of expressions of PCNA, XPB, XPD, XPF and XPG in the nucleotide exicision repair pathway (NER), which promoted the damage repair.

Effects of astragalus polysaccharide on radiation-induced adipogenic differentiation of bonemarrow mesenchymal stem cells / 西安交通大学学报(医学版)

Objective: To study the effects of astragalus polysaccharide (APS) on adipogenic differentiation of human bone marrow mesenchymal stem cells (BMSCs) irradiated by X-ray. Methods: Human bone marrow mesenchymal stem cells irradiated by 2 Gy X-ray were intervened with 50 μg/mL of APS. The number and size of lipid droplets of stem cells were observed by oil red O staining and the expressions of CEBPα and PPAR-γ were detected by Western blot after induction with special medium. Results: The number of adipocytes differentiated from bone marrow mesenchymal stem cells decreased, and the area of lipid droplets in adipocytes decreased significantly after irradiation (P<0.05). The area of lipid droplets in the bone marrow mesenchymal stem cells treated with APS in advance increased compared with that in radiation alone (P<0.05). Similarly, the expressions of PPAR-γ and recombinant human CCAAT enhancer binding protein (CEBPα ) decreased after X-ray irradiation, while the expressions of PPAR-γ and CEBPα increased after the intervention of APS (P<0.05). Conclusion: X-ray can damage the directional adipogenic differentiation of human bone marrow mesenchymal stem cells, and APS has a protective effect on the adipogenic differentiation of human bone marrow mesenchymal stem cells after X-ray irradiation.