Differential Expression of Integrin β1 in Two Brain Injury Models of Rats / 法医学杂志

Objective To study the characteristics of positive expression of integrin β1 in the rat brain tissue of two kinds of traumatic brain injury models and to explore the feasibility of inferring the mode of traumatic brain injury using the positive expression of integrin β1. Methods The occipital region of rats was hit by hydraulic impact method and pendulum striking method to produce two closed brain injury models of linear and rotation acceleration respectively, then 120 SD rats were randomly divided into linear acceleration injury group, rotation acceleration injury group, sham operation group and normal control group. Immunohistochemistry staining and Western blotting method were used to detect the positive expression of integrin β1 in different parts of the brain tissue at 30 min, 3 h, 6 h, 12 h, 3 d and 7 d after rat injury. The data was processed statistically by SPSS 18.0 software. Results The positive expression of integrin β1 was detected 30 min after brain injury and reached the peak 6 h after brain injury. With the extension of injury time, the expression tended to enhance. At the same time points after injury, the differences in the positive expression of integrin β1 between the linear acceleration injury group and the rotation acceleration injury group in the occipital strike point and thalamus had no statistical significance （ P>0.05）, but the differences in the expression of integrin β1 in the frontal lobe and brain stem had statistical significance （P<0.05）. Conclusion The characteristics of positive expression of integrin β1 in brain tissue can be used to infer the strike point and the manner of injury and has application value for the reconstruction of craniocerebral injury process.

Garlicin Post-Conditioning Suppresses Adhesion Molecules in a Porcine Model of Myocardial Ischemia-Reperfusion Injury / 中国结合医学杂志

OBJECTIVES@#To evaluate whether garlicin post-conditioning can attenuate myocardial ischemiareperfusion injury in a catheter-based porcine model of acute myocardial infarction (AMI) by affecting adhesion molecules integrin β1/CD29 and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31).@*METHODS@#Twenty-two swine were devided into 3 groups: 6 in a sham-operation group, and 8 each in the model and garlicin groups. AMI porcine model was established in the model and garlicin groups. The distal parts of the left anterior descending coronary artery in the animals of the model and garlicin groups were occluded by dilated balloon for 2 h, followed by reperfusion for 3 h. Garlicin (1.88 mg/kg) was injected over a period of 1 h, beginning just before reperfusion, in the garlicin group. Real-time polymerase chain reaction, immunohistochemistry and Western blot were carried out to detect mRNA and protein expressions of CD29 and CD31 3 h after reperfusion.@*RESULTS@#Hematoxylin-eosin staining showed a better myocardial structure in the garlicin group after reperfusion. Compared to the model group, garlicin inhibited both the mRNA and protein expression of CD29 and CD31 in reperfusion area and no-reflflow area (P<0.05 respectively).@*CONCLUSIONS@#Garlicin post-conditioning induced cardio-protection against myocardial ischemia-reperfusion injury in this catheter-based porcine model of AMI. The cardio-protective effect of garlicin is possibly owing to suppression of production of CD29 and CD31, by inhibition of the mRNA expression of CD29 and CD31.

Human plasma fibronectin promotes proliferation and differentiation of odontoblast

Abstract Objective To assess the effect of fibronectin (Fn) and porcine type I collagen (PCOL) on odontoblast-like cells in vitro. Material and Methods Rat odontoblast-like cells (MDPC-23 cells) were inoculated and cultured on Fn-coated or type I collagen-coated substrates. Proliferation assay, alkaline phosphatase activity (ALP activity), mRNA expression of hard tissue-forming markers, and Alizarin red staining were investigated over a period of 10 days. Results Cells maintained a high proliferation activity on Fn and PCOL even at a low seeding concentration (0.5×104/mL) as demonstrated by CCK-8 assay. The proliferation activity of cells on Fn increases in a concentration-dependent manner while it reached a plateau after 10 µg/mL. Cells adopted long, thin and spindle shape on Fn(10-50) and PCOL. Parallel actin filaments were observed in MDPC-23 cells cultured on Fn and PCOL. ALP activity was markedly up-regulated on Fn and PCOL-coated surfaces. Importantly, gene expression of BSP (Fn10: 2.44±0.32; Fn20: 3.05±0.01; Fn30: 2.90±0.21; Fn40: 2.74±0.30; Fn50: 2.64±0.12; PCOL: 2.20±0.03) and OCN (Fn10: 2.52±0.23; Fn20: 2.28±0.24; Fn30: 2.34±0.21; Fn40: 2.34±0.25; Fn50: 2.20±0.22; PCOL: 1.56±0.16) was significantly enhanced on Fn and PCOL substrates as compared with control; moreover, expression of integrin beta 1 (ITGB1), an ubiquitous cell surface receptor was augmented in Fn(10-50) and PCOL groups simultaneously. In accordance with the ALP activity and gene expression data, calcific deposition in cells grown on Fn(10-50) and PCOL was observed as well. Conclusion Despite the limitation of this study, the findings indicate that a surface coating of Fn enhances the proliferation, differentiation and mineralization of odontoblast-like cells by activation of integrin beta 1 (ITG B1). The promoting effects of Fn on MDPC-23 cells were achieved at a comparatively lower coating concentration than type I collagen (300 µg/mL). Specifically, it is suggested that the optimum coating concentration of Fn to be 10 µg/mL.

Effects of acupuncture at Baihui (GV 20) and Zusanli (ST 36) on peripheral serum expression of MicroRNA 124, laminin and integrin β1 in rats with cerebral ischemia reperfusion injury / 中国结合医学杂志

<p><b>OBJECTIVE</b>To explore the effects of acupuncture at Baihui (GV 20) and Zusanli (ST 36) on the peripheral serum expression of microRNA 124 (miRNA 124), laminin and integrin β1 in rats with cerebral ischemia reperfusion injury (CIRI).</p><p><b>METHODS</b>Seventy-two healthy male Sprague-Dawley rats were randomized into a model group, an acupuncture group, and a sham-operated group using a random digits table, with 24 rats per group. Each group was further randomly divided into 1-, 3-, 5-, and 7-day subgroups based on the reperfusion time according to a random digits table, with 6 rats in each subgroup. In the model and acupuncture groups, CIRI was induced using the thread occlusion method. Electroacupuncture stimulation was applied daily to GV 20 and left ST 36 for 20 min at the indicated time points after successful operations. Serum was sampled for detecting laminin and integrin β1 protein via enzyme-linked immunosorbent assay, and serum miRNA 124 was examined using quantitative polymerase chain reaction.</p><p><b>RESULTS</b>The serum level of miRNA 124 in the cerebral ischemia rats increased significantly, and the peak expression of miRNA 124 in both the model and acupuncture groups occurred at 3 days. The expression of miRNA 124 in the acupuncture group was higher than in the model group at the same time point (5.96±0.01 vs. 3.11±0.04, P <0.05). Laminin expression in serum from the cerebral ischemia group was higher than that in the sham-operated group. Compared with the model group, the level of laminin in the serum of the acupuncture group was significantly lower at each time point, especially at the 3-day, and 7-day time points (589.12±3.57 vs. 793.05±5.28, and 600.53±3.05 vs. 899.06±5.74, P <0.05). The level of integrin β1 in the serum from the acupuncture group was lower than that in the model group particularly at the 3-day and 7-day time points (208.66±0.95 vs. 280.83±1.77, and 212.36±0.95 vs. 316.77±2.42, P <0.05). Additionally, the model group and the acupuncture group showed dual peaks of integrin β1 and laminin expression at 3-day and 7-day.</p><p><b>CONCLUSIONS</b>Acupuncture at GV 20 and ST 36 in rats alleviated CIRI and was associated with upregulated expression of miRNA 124 and with downregulated expression of integrin β1 and laminin in peripheral serum. These changes may represent one of the mechanisms underlying acupuncture's attenuation of CIRI.</p>

Inhibition on Apoptosis Induced by Elevated Hydrostatic Pressure in Retinal Ganglion Cell-5 via Laminin Upregulating β1-integrin/Focal Adhesion Kinase/Protein Kinase B Signaling Pathway / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Glaucoma is a progressive optic neuropathy characterized by degeneration of neurons due to loss of retinal ganglion cells (RGCs). High intraocular pressure (HIOP), the main risk factor, causes the optic nerve damage. However, the precise mechanism of HIOP-induced RGC death is not yet completely understood. This study was conducted to determine apoptosis of RGC-5 cells induced by elevated hydrostatic pressures, explore whether laminin is associated with apoptosis under pressure, whether laminin can protect RGCs from apoptosis and affirm the mechanism that regulates the process of RGCs survival.</p><p><b>METHODS</b>RGC-5 cells were exposed to 0, 20, 40, and 60 mmHg in a pressurized incubator for 6, 12, and 24 h, respectively. The effect of elevated hydrostatic pressure on RGC-5 cells was measured by Annexin V-fluorescein isothiocyanate/propidium iodide staining, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and Western blotting of cleaved caspase-3 protein. Location and expression of laminin were detected by immunofluorescence. The expression of β1-integrin, phosphorylation of focal adhesion kinase (FAK) and protein kinase B (PKB, or AKT) were investigated with real-time polymerase chain reaction and Western blotting analysis.</p><p><b>RESULTS</b>Elevated hydrostatic pressure induced apoptosis in cultured RGC-5 cells. Pressure with 40 mmHg for 24 h induced a maximum apoptosis. Laminin was declined in RGC-5 cells after exposing to 40 mmHg for 24 h. After pretreating with laminin, RGC-5 cells survived from elevated pressure. Furthermore, β1-integrin and phosphorylation of FAK and AKT were increased compared to 40 mmHg group.</p><p><b>CONCLUSIONS</b>The data show apoptosis tendency of RGC-5 cells with elevated hydrostatic pressure. Laminin can protect RGC-5 cells against high pressure via β1-integrin/FAK/AKT signaling pathway. These results suggest that the decreased laminin of RGC-5 cells might be responsible for apoptosis induced by elevated hydrostatic pressure, and laminin or activating β1-integrin/FAK/AKT pathway might be potential treatments to prevent RGC loss in glaucomatous optic neuropathy.</p>

Integrin-ß1, not integrin-ß5, mediates osteoblastic differentiation and ECM formation promoted by mechanical tensile strain

BACKGROUND: Mechanical strain plays a great role in growth and differentiation of osteoblast. A previous study indicated that integrin-ß (ß1, ß5) mediated osteoblast proliferation promoted by mechanical tensile strain. However, the involvement of integrin-ß; in osteoblastic differentiation and extracellular matrix (ECM) formation induced by mechanical tensile strain, remains unclear. RESULTS: After transfection with integrin-ß1 siRNA or integrin-ß5 siRNA, mouse MC3T3-E1 preosteoblasts were cultured in cell culture dishes and stimulated with mechanical tensile strain of 2500 microstrain (µÎµ) at 0.5 Hz applied once a day for 1 h over 3 or 5 consecutive days. The cyclic tensile strain promoted osteoblastic differentiation of MC3T3-E1 cells. Transfection with integrin-ß1 siRNA attenuated the osteoblastic diffenentiation induced by the tensile strain. By contrast, transfection with integrin-ß5 siRNA had little effect on the osteoblastic differentiation induced by thestrain. At thesametime, theresultofECM formation promoted by the strain, was similar to the osteoblastic differentiation. CONCLUSION: Integrin-ß1 mediates osteoblast differentiation and osteoblastic ECM formation promoted by cyclic tensile strain, and integrin-ß5 is not involved in the osteoblasts response to the tensile strain.

Overexpressions of Vimentin and Integrins in Human Metastatic Spine Tumors

OBJECTIVE: To comparatively investigate the expression of several integrins in specimens of human bone metastases and degenerative bone tissue. METHODS: Degenerative cancellous tissue was obtained from a sample of human degenerative spine. Thirteen human specimens were obtained from metastatic spine tumors, whose primary cancer was colon cancer (n=3), hepatocellular cancer (n=3), lung cancer (n=4), and breast cancer (n=3). The expression of vimentin and integrins alphav, beta1, and beta3 was assessed in metastatic and degenerative specimens by immunohistochemistry and real-time reverse transcription-polymerase chain reaction (qRT-PCR). RESULTS: Immunohistochemical staining showed that vimentin and integrin alphav was broadly expressed in all tissues examined. By contrast, integrin beta1 was weakly expressed only in 38.4% (5/13) of tissues. Integrin beta3 was consistently negative in all cases examined. qRT-PCR analysis showed that vimentin gene expression was higher in all metastatic specimens, as compared to degenerative bone. The gene expression of integrin alphav in breast specimen was significantly higher than others (p=0.045). The gene expression of integrin beta1 was also higher in all metastatic specimens than in degenerative bone tissue. The gene expression of integrin beta3 was variable. CONCLUSION: Spinal metastatic tumors have mesenchymal characteristics such as increased expression of vimentin. The increased expression of integrin alphav and beta1 in spine metastatic tumors suggests that adhesive molecules such as integrin may have implications for the prevention of spine metastasis.

Assessment of alpha4, alphav, beta1 and beta3 integrins expression throughout the implantation window phase in endometrium of a mouse model of polycystic ovarian syndromes

Endometrial integrin expression changes might be a reason for implantation failure in polycystic ovarian syndromes [PCOS]. Assessment of integrin genes and proteins expression upon endometrium in the PCOS experimental mouse model was the main goal of this study. 30 NMRI female mice were equally divided into control, experimental [PCOS; received estradiol valerate [40 mg/kg]] and sham group [received; olive oil]. After 8 weeks, each group was hyper stimulated by 7 IU PMSG and then, after 48hrs, 7 IU HCG was injected. Vaginal plaque was checked. After 5 days, Progesterone and estradiol levels and endometrial tissues were investigated to evaluate of alpha4, alphav, beta1 and beta3 integrins gene and protein by qPCR method and immunohistochemistry, respectively. Tissue samples were assessed and showed that level of progesterone was significantly decreased in PCOS group. Results of molecular part in the amount of alphav, beta3, beta1 and alpha4 gene expressions showed a great difference in beta3 and alphav genes expressions between experimental groups, alphav, beta3, alpha4 and beta1 proteins in the endometrial stroma in the control group were expressed, but they were not detected in PCOS group. According to the results, integrins had different expression patterns in different areas of the endometrium; such as epithelial and stromal. It seems that in PCOS, this pattern has changed and the results might have a great influence on implantation failure. Therefore, this study suggests that a great attention to this problem may be essential in patients who are involved

Expression of alpha4, alphav, beta1 and beta3 integrins during the implantation window on blastocyst of a mouse model of polycystic ovarian syndromes

It has been hypothesized that blastocyst integrin expression changes can affect the spontaneous miscarriage in polycystic ovarian syndromes [PCOS]. In this study, the profile of integrin genes and proteins was investigated on blastocyst of the PCOS experimental mouse model. 30 NMRI female mice were equally divided into 3 groups: control, experimental [PCOS that was injected estradiol valerate [40 mg/kg]]. After 8 weeks, each group was hyper stimulated by PMSG and HCG. Vaginal plaque was checked, and mice were investigated 5 days after the test. Progesterone and estradiol levels were determined; alpha4, alpha v, beta 1 and beta 3 integrin genes and protein of blastocysts were examined by real time PCR method and immunohistochemistry, respectively. Estradiol level was significantly increased [p

Effects of Ganfukang on expression of connective tissue growth factor and focal adhesion kinase/protein kinase B signal pathway in hepatic fibrosis rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of Ganfukang (GFK) on connective tissue growth factor (CTGF) and focal adhesion kinase (FAK)/protein kinase B (PKB or Akt) signal pathway in a hepatic fibrosis rat model and to explore the underlying therapeutic molecular mechanisms of GFK.</p><p><b>METHODS</b>Fifty SD rats were randomly divided into five groups as follows: the control group, the model group (repeated subcutaneous injection of CCl4), and the three GFK treatment groups (31.25, 312.5, and 3125 mg/kg, intragastric administration). Reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting, and immunohistochemistry were used to examine the expression of CTGF, integrin α5, integrin β1, FAK/Akt signal pathway, cyclinD1, and collagen in the different-treated rats.</p><p><b>RESULTS</b>GFK attenuated the up-regulation of CTGF, integrin α5, and integrin β1 in hepatic fibrosis rats and suppressed both the phosphorylation of FAK and the phosphorylation of Akt simultaneously (P<0.01). At the same time, the expression of cyclinD1, collagen I, and collagen III was decreased by GFK significantly (P<0.01).</p><p><b>CONCLUSIONS</b>CTGF and FAK/Akt signal pathway were activated in the CCl4-induced hepatic fibrosis rats, which contribute to increased expression of cyclinD1 and collagen genes. The mechanisms of the anti-fibrosis activity of GFK may be due to its effects against CTGF and FAk/Akt signal pathway.</p>

Enhanced integrin-mediated human osteoblastic adhesion to porous amorphous calcium phosphate/poly (L-lactic acid) composite / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The initial osteoblastic adhesion to materials characterizes the first phase of cell-material interactions and influences all the events leading to the formation of new bone. In a previous work, we developed a novel amorphous calcium phosphate (ACP)/poly(L-lactic acid) (PLLA) material that demonstrated morphologic variations in its microstructure. The aim of this study was to investigate the initial interaction between this material and osteoblastic cells. Cellular attachment and the corresponding signal transduction pathways were investigated.</p><p><b>METHODS</b>A porous ACP/PLLA composite and PLLA scaffold (as a control) were incubated in fetal bovine serum (FBS) containing phosphate-buffered saline (PBS), and the protein adsorption was determined. Osteoblastic MG63 cells were seeded on the materials and cultured for 1, 4, 8, or 24 hours. Cell attachment was evaluated using the MTS method. Cell morphology was examined using scanning electron microscopy (SEM). The expression levels of the genes encoding integrin subunits α1, α5, αv, β1, focal adhesion kinase (FAK), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were determined using real-time reverse transcription polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The ACP/PLLA material significantly increased the protein adsorption by 6.4-fold at 1 hour and 2.4-fold at 24 hours, compared with the pure PLLA scaffold. The attachment of osteoblastic cells to the ACP/PLLA was significantly higher than that on the PLLA scaffold. The SEM observation revealed a polygonal spread shape of cells on the ACP/ PLLA, with the filopodia adhered to the scaffold surface. In contrast, the cells on the PLLA scaffold exhibited a spherical or polygonal morphology. Additionally, real-time RT-PCR showed that the genes encoding the integrin subunits α1, αv, β1, and FAK were expressed at higher levels on the ACP/PLLA composite.</p><p><b>CONCLUSIONS</b>The ACP/PLLA composite promoted protein adsorption and osteoblastic adhesion. The enhanced cell adhesion may be mediated by the binding of integrin subunits α1, αv, and β1, and subsequently may be regulated through the FAK signal transduction pathways.</p>

Expression of microRNA-203 and P63 in human epidermal stem cells and keratinocytes / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the changes in expression of microRNA-203 and P63 in human epidermal stem cells and KCs, and to investigate their effects and significance in the epidermal proliferation and differentiation.</p><p><b>METHODS</b>(1) Five normal foreskin tissue specimens were collected from 5 patients by circumcision in Department of Urinary Surgery of the First Affiliated Hospital of Nanchang University from March to June in 2013. Then single cell suspension was obtained by separating epidermis with trypsin digestion method. The cells were divided into quick adherent cells and non-quick adherent cells by type IV collagen differential adherent method. The biological characteristics of cells were observed by inverted phase contrast microscope immediately after isolation and on post culture day (PCD) 3. The expression of CD29, keratin 19, keratin 1, and keratin 10 was identified by immunocytochemical staining. The expression of microRNA-203 and mRNA of P63 was determined by real-time fluorescent quantitative RT-PCR. The protein expression of P63 was determined by Western blotting. Data were processed with t test and Pearson correlation analysis.</p><p><b>RESULTS</b>(1) Immediately after isolation, quick adherent cells were small, round, and dispersed uniformly. On PCD 3, the cells adhered firmly, and they grew in clones. Immediately after isolation, non-quick adherent cells appeared in different shapes and sizes, and dispersed unevenly. On PCD 3, the cells adhered precariously and did not show clonal growth. Quick adherent cells showed positive expression of CD29 and keratin 19, while non-quick adherent cells showed positive expression of keratin 1 and keratin 10. Quick adherent cells were identified as epidermal stem cells, and non-quick adherent cells were identified as KCs. (2)The expression level of microRNA-203 in epidermal stem cells (0.74 ± 0.20) was lower than that in KCs (3.66 ± 0.34, t =16.582, P <0.001). The mRNA expression level of P63 in epidermal stem cells (4. 16 ± 0.28) was higher than that in KCs (2.90 ± 0.39, t =5. 850, P =0.001). The protein expression level of P63 in epidermal stem cells (1.42 ± 0.05) was higher than that in KCs (0.73 ± 0.03, t =26.460, P <0. 001). (3) The expression level of microRNA-203 was in significantly negative correlation with the expression levels of mRNA and protein of P63 (with r values respectively - 0. 94 and -0.98 , P values below 0.05).</p><p><b>CONCLUSIONS</b>The expression levels of microRNA-203 and P63 in human epidermal stem cells and KCs were significantly different, which might be related to the different characteristics of proliferation and differentiation of the cells.</p>

Kindlin-2 regulates migration and adhesion of vascular smooth muscle cells via β1-integrin / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the effects of Kindlin-2 RNA interference on vascular smooth muscle cells (VSMCs) migration, adhesion and β1-integrin as well as the relationship between Kindlin-2 and β1-integrin.</p><p><b>METHODS</b>Primary VSMCs were cultured, infected with Kindlin-2 siRNA lentiviral vectors.VSMCs were divided into three groups:the blank control group, the negative control group and the Kindlin-2 siRNA group. The ability of VSMCs migration was measured by Transwell experiment and wound healing assay. The ability of VSMCs adhesion to extracelluar matrix was determined by cell-extracelluar matrix adhesion assay. The Kindlin-2 and β1-integrin mRNA and protein expression levels were detected by real-time quantitative PCR and Western blot. Total β1-integrin and active β1-integrin expression on the surface of VSMCs was evaluated by flow cytometry.</p><p><b>RESULTS</b>The efficiency of Kindlin-2 siRNA lentivirus infected VSMCs was more than 90%. The number of VSMCs migration in the Kindlin-2 siRNA group was significantly lower than that of the blank control group and the negative group (all P < 0.05). Moreover, the distance of VSMCs migration was shorter than that of the blank control group and the negative group (all P < 0.05). The number of VSMCs adhesion to collagen I was less than that of the blank control group and the negative group (all P < 0.05). A(590 nm) of the Kindlin-2 siRNA group was also lower than that of the blank control group and the negative group (all P < 0.05). Compared with the blank control group, the expression level of Kindlin-2 mRNA in the Kindlin-2 siRNA group decreased 47% (P < 0.05), but the expression level of β1-integrin mRNA remained unchanged. The Kindlin-2 protein level in the Kindlin-2 siRNA group was lower than that of the blank control group and the negative group (all P < 0.05). β1-integrin protein level was similar among the three groups. Activated β1-integrin on the surface of VSMCs in the Kindlin-2 siRNA group was lower than that of the blank control group and the negative group (all P < 0.05).However, the expression level of total β1-integrin on the VSMCs surface was similar among the three groups.</p><p><b>CONCLUSION</b>Kindin-2 can regulate VSMCs migration and adhesion and activate β1-integrin on the surface of VSMCs.</p>

Evaluation of CD24 as a marker to rapidly define the mesenchymal stem cell phenotype and its differentiation in human nucleus pulposus / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Recent studies have indicated that human nucleus pulposus contain mesenchymal stem cells (NP-MSCs). However, the immunophenotypic variation of NP-MSCs in vitro was unclear. The present study was conducted to address the immunophenotypic variation of mesenchymal stem cells in nucleus pulposus under continuous proliferation in vitro and show the difference between mesenchymal stem cells and nucleus pulposus cell.</p><p><b>METHODS</b>Tissue samples were obtained from thoracolumbar burst fracture patients and degenerative disc disease patients who underwent discectomy and fusion procedures. Flow cytometric and laser scanning confocal microscope (LSCM) were used to detect the variation of mesenchymal stem cells in nucleus pulposus which were expressing CD105 and CD24 in condition with or without transforming growth factor β1 (TGF-β1).</p><p><b>RESULTS</b>More than 90% of the analyzed primary cells of mesenchymal stem cells in nucleus pulposus fulfilled the general immunophenotyping criteria for MSCs, such as CD44, CD105 and CD29, but the marker of mature NP cells characterized as CD24 was negative. In continuous cultures, the proportion of mesenchymal stem cells which were expressing CD44, CD105 and CD29 in nucleus pulposus gradually decreased. The mesenchymal stem cells in nucleus pulposus cells were positive for CD105 and CD29, with slight positivity for CD44. The CD24 expression gradually increased in proliferation. Biparametric flow cytometry and laser scanning confocal microscopy confirmed the presence of cells which were expressing CD105 and CD24 independently, and only a small part of cells expressed both CD105 and CD24 simultaneously. TGF-β1 could stimulate mesenchymal stem cells in nucleus pulposus to express CD24.</p><p><b>CONCLUSIONS</b>Non-degenerative and degenerative NP contains mesechymal stem cells. The variation of CD24 can be used as a marker to identify the NP-MSCs differentiation into NP-like cells.</p>

beta1-integrin-dependent migration of microglia in response to neuron-released alpha-synuclein

Chronic neuroinflammation is an integral pathological feature of major neurodegenerative diseases. The recruitment of microglia to affected brain regions and the activation of these cells are the major events leading to disease-associated neuroinflammation. In a previous study, we showed that neuron-released alpha-synuclein can activate microglia through activating the Toll-like receptor 2 (TLR2) pathway, resulting in proinflammatory responses. However, it is not clear whether other signaling pathways are involved in the migration and activation of microglia in response to neuron-released alpha-synuclein. In the current study, we demonstrated that TLR2 activation is not sufficient for all of the changes manifested by microglia in response to neuron-released alpha-synuclein. Specifically, the migration of and morphological changes in microglia, triggered by neuron-released alpha-synuclein, did not require the activation of TLR2, whereas increased proliferation and production of cytokines were strictly under the control of TLR2. Construction of a hypothetical signaling network using computational tools and experimental validation with various peptide inhibitors showed that beta1-integrin was necessary for both the morphological changes and the migration. However, neither proliferation nor cytokine production by microglia was dependent on the activation of beta1-integrin. These results suggest that beta1-integrin signaling is specifically responsible for the recruitment of microglia to the disease-affected brain regions, where neurons most likely release relatively high levels of alpha-synuclein.

Effect of Jingang Jiangu pill (see text) on expression of integrin beta1 and alphavbeta3 in ovariectomized osteoporosis model rats / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the regulatory effect of Jingang Jiangu pill (see text, JGJG) on expression of integrin in ovariectomized rats.</p><p><b>METHODS</b>Fifty ovariectomized 10 months old female rats were randomly divided into 5 groups: Fushanmei group (FSM), Jingang Jiangu pill (see text) group (JGJG), Gusongbao granule group (GSB), Model group (OVX), Sham group. After ovariectomized,the rats were raised in the same environment for 13 weeks. The rats in JGJG group took 0.13 g JGJG pill orally each day for each rat; the rats in GSB group took 0.86 g GSB granule orally each day for each rat; the rats in FSM group took 0.28 mg FSM orally each day for each rat; and the rats in OVX and sham groups took sodium. The treatment duration of rats in above 5 groups was 13 weeks. Bone mineral density (BMD) and the expression of integrin beta1 and alphavbeta3 were detected in each group after the treatment. RESYKTS: The BMD and the expression of integrin beta1 in FSM group, JGJG group and GSB group improved obviously than that of OVX group. There were statistical difference between these groups (P<0.05). The expression of integrin alphavbeta3 of the three treating groups significantly depressed.</p><p><b>CONCLUSION</b>The JGJG pill improves BMD and express of integrin beta1, in ovariectomized rats and reduces express of integrin alphavbeta3 through the regulation of the coupling of osteoblasts and osteoclasts.</p>

Expression of integrin α5 and β1 in osteoblast in the process of gingipains-induced apoptosis / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the regulatory mechanisms of integrin α5 and β1 in osteoblast in the process of gingipains-induced apoptosis.</p><p><b>METHODS</b>Gingipains were isolated and purified from supernatants of Porphyromonas gingivalis W83 which was cultured under standard anaerobic conditions. MC3T3-E1 was challenged with or without 8.3480 U/L gingipains for 48 h and apoptosis was examined by transferase-mediated deoxyuridine triphosphate-biotin nick end labeling-(4-Amidinophenyl)-6-indolecarbamidine dihydrochloride (TUNEL-DAPI) staining. The expression of integrin α5 and β1 was analyzed by Western blotting after MC3T3-E1 was treated under different conditions.</p><p><b>RESULTS</b>Arginine-specific proteinases(Rgp) activity was (41.74 ± 2.11) U/L and lysine-specific proteinase(Kgp) was (1.02 ± 0.25) U/L.Gingipains induced MC3T3-E1 cells apoptosis after 48 h. Compared with control group, expression of integrin α5 and β1 was down-regulated by gingipains in a time-dependent manner within short periods ( ≤ 72 h), integrin α5 and β1 relative expression was (0.485 ± 0.039),(0.504 ± 0.002) at 48 h,(0.398 ± 0.058),(0.179 ± 0.001) at 72 h respectively (P < 0.05). After 72 h, integrin α5 expression in MC3T3-E1 cells was stable compared with control group while integrin β1 was still lower(control group:1.000 ± 0.000, 96 h:0.604 ± 0.003, 120 h: 0.357 ± 0.002) (P < 0.05). Proteinase inhibitor tosyl- L- lysine-chloromethyl-ketone(TLCK) effectively blocked the activity of gingipain and inhibited down-regulation of integrin α5 and β1 induced by gingipains from (0.398 ± 0.058,0.179 ± 0.001 ) to (0.781 ± 0.012, 0.857 ± 0.060) (P < 0.05). TLCK alone did not have any effect on integrin α5 and β1(P > 0.05). Gingipains also decreased integrin α5 and β1 in a dose-dependent manner.When cells were treated with 20.8700 U/L gingipains, integrin α5 and β1 relative expression reached to the lowest(0.105 ± 0.004,0.020 ± 0.000) (P < 0.05).</p><p><b>CONCLUSIONS</b>Gingipains inhibited the expression of integrin α5 and β1 in a time- and dose- dependent manner in osteoblasts in the process of apoptosis, which may not be mediated by direct proteolytic effect.</p>

Transforming growth factor-β1 regulates renal α3 and β1 integrin expressions in diabetic rats: a new insight into the renoprotective effect of irbesartan / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the association between renal transforming growth factor-β1 (TGF-β1) and the expressions of α3 and β1 integrins and observe the effect of irbesartan on their expressions in diabetic rats.</p><p><b>METHODS</b>Thirty 8-week-old male Wistar rats were randomly divided into normal control group (n=7), diabetic control group (n=14) and irbesartan group (n=9). Rat models of diabetes were established by a single peritoneal injection of streptozotocin (STZ), and 4 weeks later the rats received irbesartan treatment for 8 weeks. Enzyme-linked immunosorbent assay (ELISA) was used to measure the urinary albumin excretion rate, and PAS staining was utilized to observe the renal pathologies. Immunohistochemistry was performed for semi-quantitative determination of podocyte density, and real-time RT-PCR was used to detect the renal TGF-β1 and α3/β1 integrin mRNA expressions.</p><p><b>RESULTS</b>In diabetic rats, the expression of renal TGF-β1 mRNA was significantly increased, while α3 and β1 integrin mRNA expressions and podocyte density significantly decreased with increased proteinuria. Irbesartan obviously improved such changes.</p><p><b>CONCLUSION</b>In diabetic rats renal TGF-β1 can regulate α3 and β1 integrin mRNA expressions to reduce the number of podocytes, and inhibition of this pathway may be one of the mechanisms of the renal protective effect of irbesartan.</p>

Effect of substrate stiffness on biological behavior of fibroblasts / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the effect of substrate stiffness on proliferation, migration of fibroblast and integrin β(1) expression in fibroblast.</p><p><b>METHODS</b>Fibroblasts were inoculated on silicon substrate with stiffness of (16.2 ± 0.5), (19.8 ± 1.1), and (200.1 ± 2.6) kPa. After being cultured for 5 days or 6 days, cells were counted and cell proliferative activities (recorded as absorbance value) were assessed with methyl thiazolyl blue (MTT). After being cultured for 3 days, cell cycle was detected and proliferation index (PI) was calculated. The cell scratch test was used for determination of cell migration rate on post scratch day (PSD) 0 (the day of scratch), 1, 2, and 3. After being cultured for 2 days, the expression of integrin β(1) was determined by flow cytometry with fluorescence. Data were processed with one-way analysis of variance.</p><p><b>RESULTS</b>(1) The proliferative speed and proliferative activity of fibroblasts were all increased along with the increase in substrate stiffness. PI of fibroblasts inoculated on silicon substrate with stiffness of (16.2 ± 0.5), (19.8 ± 1.1), and (200.1 ± 2.6) kPa was respectively 24.8%, 27.4%, 32.4%. On PSD 2, migration rate of fibroblasts inoculated on silicon substrate with stiffness of (19.8 ± 1.1) and (200.1 ± 2.6) kPa was respectively (91.4 ± 5.1)%, (100.0 ± 1.3)%, which were higher than that of fibroblasts inoculated on silicon substrate with stiffness of (16.2 ± 0.5) kPa [(55.8 ± 6.8)%, with F value respectively 3.5, 4.0, P values all below 0.01]. (3) The expression rate of integrin β(1) in fibroblasts inoculated on silicon substrate with stiffness of (16.2 ± 0.5) kPa was the lowest (43.22%), and that in fibroblast inoculated on silicon substrate with stiffness of (200.1 ± 2.6) kPa was the highest (81.26%).</p><p><b>CONCLUSIONS</b>Substrate stiffness may have a great effect on proliferation and migration of fibroblast during the process of wound healing and scar formation, which can be related to regulation of integrin β(1) expression.</p>

[ effect of laminin and gelatin extracellular matrix on short-term cultivation of neonate mouse spermatogonial stem cells]

To compare the effect of laminin and gelatin on short-term culture of spermatogonial stem cells [SSCs] from neonatal mouse testes. Cell suspension containing SSCs were isolated from testes of 6 day-old mice and cultured in the presence of Glial-derived neuroterophic factor [GDNF], Epidermal Growth Factor [EGF] and Basic Fibroblastic Growth Factor [bFGF] on laminin-and gelatin-coated plates for 9 days. Number and area of colonies were measured in 5th, 7th and 9th days after culturing. At 9th day Immunostaining was used to detect expression of SSC markers, alpha 6-Integrin and beta 1-Integrin. moreover, the colonies were harvested and the percentage of alpha 6-Integrin and beta 1-Integrin positive cells was assessed by flowcytometery in both groups. Immunostaining analysis showed that our culture system contained SSC colonies as they were positive for alpha 6-Integrin and beta 1-Integrin. Additionally, the number of colonies those were formed on laminin were significantly higher in comparison with those of other group. but colony area was higher on gelatin. There was no significant difference in percentage of cells that expressed alpha 6-Integrin, beta 1-Integrin detected by flowcytometry in both groups. laminin as extracellular matrix cause to increase the number of neonate spermatogonial colonies and decrease the area of them [P