Effects of Estrogen Level on the Function of Vascular Endothelial Cells and Expression of Vascular Cell Adhesion Molecule-1(?)

Objectives To ob-serve the effect of different estrogen levels on the secretory function of vascular endothelial cells of female rats, and study the effect of modulation of estrogen level on the expression of vascular cell adhesion molecule - 1 and the concentration of estrogen receptor in vascular endothelial cells. Methods Radioim-munology was used to measure the serum concentration of endothelin and PGI2, and copper - cadmium reduction was employed to measure the serum content of nitrogen monoxide. Radioligand binding and flowcy-tometry were used to measure the expression of estrogen receptor and vascular cell adhesion molecule (VCAM - 1) of vascular endothelial cells respectively. Results 1. The serum concentration of nitric oxide and PGI2 decreased when the ovaries of female rats were removed. In ovariectomized rats, given estrogen, the concentration rose ( P < 0. 05), but the plasma concentration of endothelin was adverse to it. 2. The concentration of estrogen receptor of vascular endothelial cells decreased remarkably when the ovaries of female rats were removed. When given estrogen, it increased. 3. The percent of expressed VCAM - 1 increased significantly after interleukin - 1βoperated on the cells, but 17 -βestradiol at 3 × 10-8 - 10-6 mol/l all decreased the percent. Conclusions Estrogen level can influence the secretion of nitrogen monoxide, PGI2 and endothlin of vascular endothelial cells, and also influence the concentration of estrogen receptor of vascular endothelial cells. 17 -β Estradiol at 3 × 10-8 -10-6 M can decrease the elevation of VCAM - 1 of vascular endothelial cells induced by interleukin - 1β.

Expression of platelet endothelial cell adhesion molecule-1 between pancreatic microcirculation and peripheral circulation in rats with acute edematous pancreatitis

OBJECTIVE: To study the ehanges of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation anti pancreatic microcirculation in rats with acute edematous pancreatitis (AEP). METHODS: The model of AEP was established with 50 Wistar rats, and the changes of PECAM-1 expression on PMNs from the splenic vein and inferior vena cava were determined by flow cytometry. RESULTS: PECAM-I expression on PMNs showed no significant difference between pancreatic microcirculation and peripheral circulation at AEP2h and AEP4h time points. From the AEP4h to the AEP8h time point, PECAM-1 expression in peripheral circulation was up-regulated, but PECAM-1 expression in pancreatic microcirculation was down-regulated. PECAM-1 expression had a significant difference between pancreatic microcirculation and peripheral circulation at the AEP8h time point (P<0.05). CONCLUSION: PECAM-1 expression on PMNs is in a converse way between pancreatic microcirculation and peripheral circulation in AEP.

Effects of TCMP-1 on the changes of platelet endothelial cell adhesion molecule-1 expression in acute edematous pancreatitis

BACKGROUND: Traditional Chinese medicine is a potent agent in the management of clinical and experimental acute pancreatitis (AP), but the molecular mechanism of its the- rapeutic action is unclear. Numerous experimental and clinical studies have shown that platelet endothelial cell ad- hesion molecule-1 (PECAM-1) is pivotal to leukocyte re- cruitment, which results in microcirculatory injury during inflammation, but its role in acute pancreatitis is poorly un- derstood. We investigated the effects of a compound of tra- ditional Chinese medicine pancreatitis-1 (TCMP-1) on the changes of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in acute edematous pancreatitis (AEP). METHODS: The model of acute pancreatitis was estab- lished by subcutaneous injection of caerulein, and TCMP-1 treated groups were given TCMP-1 by catheterization from mouth to stomach (20 ml/kg) immediately after first time subcutaneous injection of caerulein. The changes of expres- sion of PECAM-1 on leukocytes from the blood of the splenic vein and inferior vena cava were determined by flow cytometry. RESULTS: In the AEP group, expression of PECAM-1 on PMNs was not significantly different between pancreatic microcirculation and systemic circulation at AEP2h and AEP4h time point. Then from AEP4h time point to AEP8h time point, expression of PECAM-1 was up-regulated in systemic circulation while it was down-regulated in pancre- atic microcirculation and was significantly different be- tween pancreatic microcirculation and systemic circulation at AEP8h time point (P<0.05). In the TCMP-1 treated group, compared with the AEP group, expression of PE-CAM-1 on PMNs decreased in different levels between pan- creatic microcirculation and systemic circulation and was of significant difference at AEP8h time point (P <0.05). CONCLUSION: Inhibition of PECAM-1 expression on PMNs may prevent PMNs from transmigration through the endo- thelium and may be one of the treatment mechanisms of TCMP-1 decoction on AEP.

The relationship between platelet endothelial cell adhesion molecule-1 and paraquat-induced lung injury in rabbits

BACKGROUND:Platelet endothelial cell adhesion molecule-1(PECAM-1),also known as CD31,is mainly distributed in vascular endothelial cells.Studies have shown that PECAM-1 is a very significant indicator of angiogenesis,and has been used as an indicator for vascular endothelial cells.The present study aimed to explore the relationship between the expression of PECAM-1 and the degree of acute lung injury(ALI) and fibrosis in paraquat(PQ) induced lung injury in rabbits.METHODS:Thirty-six adult New Zealand rabbits were randomly divided into three groups(12rabbits in each group) according to PQ dosage:8 mg/kg(group A),16 mg/kg(group B),and 32 mg/kg(group C).After PQ infusion,the rabbits were monitored for 7 days and then euthanized.The lungs were removed for histological evaluation.Masson staining was used to determine the degree of lung fibrosis(LF),and semi-quantitative immune-histochemistry analysis to determine the expression of PECAM-1.Pearson's product-moment correlation analysis was performed to evaluate the relationship between the expression of PECAM-1 and the extent of lung injuries expressed by ALI score and degree of LF.RESULTS:Rabbits in the three groups showed apparent poisoning.The rabbits survived longer in group A than in groups B and C(6.47±0.99 days vs.6.09±1.04 days vs.4.77±2.04 days)(P<0.05).ALI score was lower in group A than in groups B and C(8.33±1.03 vs.9.83±1.17 vs.11.50±1.38)(P<0.05),and there was statistically significant difference between group B and group C(P=0.03).LF was slighter in group A than in groups B and C(31.09%±2.05%vs.34.37%±1.62%vs.36.54%±0.44%)(P<0.05),and there was statistically significant difference between group B and group C(P=0.026).The PEACAM-1 expression was higher in group A than in groups B and C(20.31%±0.70%vs.19.34%±0.68%vs.18.37%±0.46%)(P<0.05),and there was statistically significant difference between group B and group C(P=0.017).Pearson's correlation analysis showed that the expression of PECAM-1 was negatively correlated to both ALI score(Coe=-0.732,P=0.001)and degree of LF(Coe=-0.779,P<0.001).CONCLUSIONS:The PECAM-1 expression significantly decreases in New Zealand rabbits after PQ poisoning,and the decrease is dose-dependent.The PECAM-1 expression is negatively correlated with ALI score and LF,showing a significant role in the development of lung injuries induced by PQ.

Differences in platelet endothelial cell adhesion molecule-1 expression between peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis

AIM: To investigate the changes of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis (AEP).METHODS: Fifty Wistar rats were randomly divided into control group (n=10) and AEP group (n=40). A model of AEP was established by subcutaneous injection of cerulein 5.5 and 7.5 μg/kg at 0 and 1 h after the beginning of experiment respectively. PECAM-1 expression on PMNs from splenic vein and inferior vena cava was determined by RT-PCR at mRNA level and determined by flow cytometry at protein level.RESULTS: In experimental rats, an increased PECAM-1mRNA expression was seen from 4 to 8 h of AEP in peripheral circulation (0.77±0.25%, 0.76±0.28%, 0.89±0.30%,1.00±0.21% ), while in pancreatic microcirculation,expression decreased from 2 h and reached the lowest level at 6 h of AEP (0.78±0.29%, 0.75±0.26%, 0.62±0.28%,0.66±0.20%). There were significant differences at 8-h time point of AEP between peripheral circulation and pancreatic microcirculation (1.00±0.21% vs0.66±0.20%, P＜0.05).Meanwhile,the difference at protein level was also found.CONCLUSION: A reverse expression of PECAM-1 on PMNs was found between peripheral circulation and pancreatic microcirculation, suggesting that inhibition of PECAM-1expression may improve the pathological change of AEP.

Cytokine-Induced Cell Surface Expression of Adhesion Molecules in Vascular Endothelial Cells In vitro

Regulation of the adhesion molecules expression by cytokine in vascular endothelial cells was investigated. Human umbilical vein endothelial cells (HUVEC) were stimulated with cytokines, TNF α (1-250 U/ml) or IL 1β (0.1-50 U/ml) for 24 h. HUVEC were also cultured with cytokines, TNF α (100 U/ml) or IL 1β (10 U/ml), for 4-72 h, cell surface expression of adhesion molecules (ICAM 1 and VCAM 1) were detected and quantitated by immunocytochemical methods and computerized imaging analysis technique. Adhesion molecules expression were up regulated by TNF α, IL 1β in a concentration and time dependent manner. Some significant differences were observed between the effects of cytokines on the ICAM 1 and on VCAM 1 expression. Cytokines might directly induce the expression of ICAM 1 and VCAM 1 in vascular endothelial cells. Our observations indicate differential functions of the two adhesion molecules during the evolution of inflammatory responses in stroke.

Association of G+1688A Polymorphism of Platelet Endothelial Cell Adhesion Molecule-1 Gene with Myocardial Infarction in the Chinese Han Population

In order to investigate the association of G＋1688A （Ser563Asn） polymorphism of platelet endothelial cell adhesion molecule-1 （PECAM-1） gene with myocardial infarction （MI） in the Chinese Han population, the G＋1688A polymorphism in PECAM-1 gene was detected by polymerase chain reaction-restriction fragment-length polymorphism （PCR-RFLP） method among 502 subjects, including 218 patients with MI and 284 controls. The results showed that there was significant difference in AA frequencies of genotype G＋1688A polymorphism between case and control groups （39% vs 24%, P〈0.001）. A similar trend was observed on the allele frequencies （A/G： 62% vs 49%, P〈0.001）. Among the subjects with high serum total cholesterol level or high systolic blood pressure level, the variant AA genotype was associated with high risk of MI （adjusted OR, 2.13; 95% CI, 1.08 -4.41 and adjusted OR, 2.53; 95%CI, 1.63-3.63）. The single nucleotide polymorphism （SNP） at position ＋1688 in the exon 8 of PECAM-1 gene was associated with MI and the allele A might be a risk factor for MI in the Chinese Han population.

Hypoxia Inhibits Proliferation of Human Dermal Lymphatic Endothelial Cells via Downregulation of Carcinoembryonic Antigen-related Cell Adhesion Molecule 1 Expression

Objective:Lymphatic endothelial cell(LEC)proliferation is essential for lymphangiogenesis.Hypoxia induces lymphangiogenesis,but it directly inhibits LEC proliferation and the underlying mechanisms have not been fully understood.The aim of this study was to investigate the role of carcinoembryonic antigen-related cell adhesion molecule 1(CEACAM1)in hypoxia-repressed LEC proliferation.Methods:Human dermal lymphatic endothelial cells(HDLECs)were cultured under normoxic or hypoxic conditions,and cell proliferation was determined using MTT or CCK-8 assays.CEACAM1 expression was silenced by siRNA transfection.Activation of mitogen-activated protein kinases(MAPKs)was examined by Western blotting and blocked by specific inhibitors.Results:Under hypoxia,HDLECs proliferation was suppressed and CEACAM1 expression was downregulated.Silence of CEACAM1 in normoxia inhibited HDLECs proliferation and did not further decrease proliferation in HDLECs in response to hypoxia,suggesting that CEACAM1 may mediate hypoxia-induced inhibition of HDLECs proliferation.In addition,silence of CEACAM1 increased phosphorylation of MAPK molecules:extracellular signal-regulated kinase(ERK),p38 MAPK and Jun N-terminal kinase(JNK)in HDLECs.However,only inhibition of the JNK pathway rescued the reduction of HDLEC proliferation induced by CEACAM1 silence.Conclusion:Our results suggested that hypoxia downregulates CEACAM1 expression by activation of the JNK pathway,leading to inhibition of HDLEC proliferation.These findings may help to understand the mechanisms of LEC-specific response to hypoxia and develop novel therapies for pathological lymphangiogenesis.

Knockdown of fibrillin-1 suppresses retina-blood barrier dysfunction by inhibiting vascular endothelial apoptosis under diabetic conditions

AIM:To investigate the effects of fibrillin-1(FBN1)deletion on the integrity of retina-blood barrier function and the apoptosis of vascular endothelial cells under diabetic conditions.METHODS:Streptozotocin(STZ)-induced diabetic mice were used to simulate the diabetic conditions of diabetic retinopathy(DR)patients,and FBN1 expression was detected in retinas from STZ-diabetic mice and controls.In the Gene Expression Omnibus(GEO)database,the GSE60436 dataset was selected to analyze FBN1 expressions in fibrovascular membranes from DR patients.Using lentivirus to knock down FBN1 levels,vascular leakage and endothelial barrier integrity were detected by Evans blue vascular permeability assay,fluorescein fundus angiography(FFA)and immunofluorescence labeled with tight junction marker in vivo.High glucose-induced monkey retinal vascular endothelial cells(RF/6A)were used to investigate effects of FBN1 on the cells in vitro.The vascular endothelial barrier integrity and apoptosis were detected by trans-endothelial electrical resistance(TEER)assay and flow cytometry,respectively.RESULTS:FBN1 mRNA expression was increased in retinas of STZ-induced diabetic mice and fibrovascular membranes of DR patients(GSE60436 datasets)using RNA-seq approach.Besides,knocking down of FBN1 by lentivirus intravitreal injection significantly inhibited the vascular leakage compared to STZ-DR group by Evans blue vascular permeability assay and FFA detection.Expressions of tight junction markers in STZ-DR mouse retinas were lower than those in the control group,and knocking down of FBN1 increased the tight junction levels.In vitro,30 mmol/L glucose could significantly inhibit viability of RF/6A cells,and FBN1 mRNA expression was increased under 30 mmol/L glucose stimulation.Down-regulation of FBN1 reduced high glucose(HG)-stimulated retinal microvascular endothelial cell permeability,increased TEER,and inhibited RF/6A cell apoptosis in vitro.CONCLUSION:The expression level of FBN1 increases in retinas and vascular endothelial cells under diabetic conditions.Down-regulation of FBN1 protects the retina of early diabetic rats from retina-blood barrier damage,reduce vascular leakage,cell apoptosis,and maintain vascular endothelial cell barrier function.

Early expressions of hypoxia-inducible factor 1alpha and vascular endothelial growth factor increase the neuronal plasticity of activated endogenous neural stem cells after focal cerebral ischemia

Endogenous neural stem cells become ＂activated＂ after neuronal injury, but the activation sequence and fate of endogenous neural stem cells in focal cerebral ischemia model are little known. We evaluated the relationships between neural stem cells and hypoxia-inducible factor-1α and vascular endothelial growth factor expression in a photothromobotic rat stroke model using immunohistochemistry and western blot analysis. We also evaluated the chronological changes of neural stem cells by 5-bromo-2′-deoxyuridine（BrdU） incorporation. Hypoxia-inducible factor-1α expression was initially increased from 1 hour after ischemic injury, followed by vascular endothelial growth factor expression. Hypoxia-inducible factor-1α immunoreactivity was detected in the ipsilateral cortical neurons of the infarct core and peri-infarct area. Vascular endothelial growth factor immunoreactivity was detected in bilateral cortex, but ipsilateral cortex staining intensity and numbers were greater than the contralateral cortex. Vascular endothelial growth factor immunoreactive cells were easily found along the peri-infarct area 12 hours after focal cerebral ischemia. The expression of nestin increased throughout the microvasculature in the ischemic core and the peri-infarct area in all experimental rats after 24 hours of ischemic injury. Nestin immunoreactivity increased in the subventricular zone during 12 hours to 3 days, and prominently increased in the ipsilateral cortex between 3–7 days. Nestin-labeled cells showed dual differentiation with microvessels near the infarct core and reactive astrocytes in the peri-infarct area. BrdU-labeled cells were increased gradually from day 1 in the ipsilateral subventricular zone and cortex, and numerous BrdU-labeled cells were observed in the peri-infarct area and non-lesioned cortex at 3 days. BrdU-labeled cells rather than neurons, were mainly co-labeled with nestin and GFAP. Early expressions of hypoxia-inducible factor-1α and vascular endothelial growth factor after ischemia made up the microenvironment to increase the neuronal plasticity of activated endogenous neural stem cells. Moreover, neural precursor cells after large-scale cortical injury could be recruited from the cortex nearby infarct core and subventricular zone.

Vascular endothelial growth factor A, secreted in response to transforming growth factor-β1 under hypoxic conditions, induces autocrine effects on migration of prostate cancer cells

Hypoxia and transforming growth factor-β1 （TGF-β1） increase vascular endothelial growth factor A （VEGFA） expression in a number of malignancies. This effect of hypoxia and TGF-β1 might be responsible for tumor progression and metastasis of advanced prostate cancer. In the present study, TGF-β1 was shown to induce VEGFA165 secretion from both normal cell lines （HPV7 and RWPE1） and prostate cancer cell lines （DU 145 and PC3）. Conversely, hypoxia-stimulated VEGFA165 secretion was observed only in prostate cancer cell lines. Hypoxia induced TGF-β1 expression in PC3 prostate cancer cells, and the TGF-β1 type I receptor （ALK5） kinase inhibitor partially blocked hypoxia-mediated VEGFA16s secretion. This effect of hypoxia provides a novel mechanism to increase VEGFA expression in prostate cancer cells. Although autocrine signaling of VEGFA has been implicated in prostate cancer progression and metastasis, the associated mechanism is poorly characterized. VEGFA activity is mediated via VEGF receptor （VEGFR） 1 （Fit-l） and 2 （FIk-I/KDR）. Whereas VEGFR-1 mRNA was detected in normal prostate epithelial cells, VEGFR-2 mRNA and VEGFR protein were expressed only in PC3 cells. VEGFA165 treatment induced phosphorylation of extracellular signal-regulated kinase 1/2 （ERKI/2） in PC3 cells but not in HPV7 cells, suggesting that the autocrine function of VEGFA may be uniquely associated with prostate cancer. Activation of VEGFR-2 by VEGFA165 was shown to enhance migration of PC3 cells. A similar effect was also observed with endogenous VEGFA induced by TGF-β1 and hypoxia. These findings illustrate that an autocrine loop of VEGFA via VEGFR-2 is critical for the tumorigenic effects of TGF-β1 and hypoxia on metastatic prostate cancers.

Small interfering RNA targeting PGC-1α inhibits VEGF expression and tube formation in human retinal vascular endothelial cells

AIMTo determine whether small interfering RNA (siRNA) of PGC-1α could inhibit vascular endothelial growth factor (VEGF) expression and tube formation in human retinal vascular endothelial cells (hRVECs).METHODShRVECs transfected with peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) siRNA were incubated for 24h and then placed into a normoxic (20%, O2) or hypoxic (1%, O2) environment for another 16h. PGC-1α mRNA and protein levels were detected by real-time PCR and Western blot. VEGF mRNA and protein levels were detected by real-time PCR and ELISA. Cell proliferation was evaluated by BrdU incorporation assay. Forty-eight hours after siRNA transfection, hRVECs were planted into Matrigel-coated plates and cultured under normoxic (20%, O2) or hypoxic (1%, O2) conditions for another 48h. The tube formation of hRVECs was observed under an optical microscope and quantified by counting the number of branch points and calculating the total tube length.RESULTSPGC-1α mRNA and protein levels were significantly reduced by PGC-1α siRNA, and VEGF mRNA and protein levels also decreased significantly. The percentage of BrdU-labeled cells in siPGC-1α groups were significantly decreased compared with control siRNA groups under normoxia and hypoxia in cell proliferation assay. In the tube formation assay, PGC-1α siRNA treated cells formed significantly fewer tubes.CONCLUSIONBlocking PGC-1α expression can inhibit VEGF expression in hRVECs and inhibit their ability to form tubes under both normoxic and hypoxic conditions.

Adhesion molecule and proinflammatory cytokine gene expression in hepatic sinusoidal endothelial cells following cecal ligation and puncture

INTRODUCTIONMultiple organ dysfunction syndrome (MODS) isthought to be a frequent consequence of sepsis[1-3].Despite substantial advances in our knowledge and understanding of the basic pathophysiologic mechanisms[4-7], in critically ill patients infections and sepsis are still associated with a high mortality[8,9].

Adhesion of different cell cycle human hepatoma cells to endothelial cells and roles of integrin β_1

AIM: To investigate the adhesive mechanical properties of different cell cycle human hepatoma cells (SMMC-7721) to human umbilical vein endothelial cells (ECV-304), expression of adhesive molecule integrinβ1 in SMMC-7721 cells and its contribution to this adhesive course. METHODS: Adhesive force of SMMC-7721 cells to endothelial cells was measured using micropipette aspiration technique. Synchronous G1 and S phase SMMC-7721 cells were achieved by thymine-2-deoxyriboside and colchicines sequential blockage method and double thymine-2-deoxyriboside blockage method, respectively. Synchronous rates of SMMC-7721 cells and expression of integrinβ1 in SMMC-7721 cells were detected by flow cytometer. RESULTS: The percentage of cell cycle phases of general SMMC-7721 cells was 11.01% in G2/M phases, 53.51% in G0/G1 phase, and 35.48% in S phase. The synchronous rates of G1 and S phase SMMC-7721 cells amounted to 74.09% and 98.29%, respectively. The adhesive force of SMMC-7721 cells to endothelial cells changed with the variations of adhesive time and presented behavior characteristics of adhesion and de-adhesion. S phase SMMC-7721 cells had higher adhesive forces than d phase cells [(307.65±92.10)×10-10N vs(195.42±60.72)×10-10N, P<0.01]. The expressive fluorescent intensity of integrinβ1 in G1 phase SMMC-7721 cells was depressed more significantly than the values of S phase and general SMMC-7721cells. The contribution of adhesive integrinβ1 was about 53% in this adhesive course. CONCLUSION: SMMC-7721 cells can be synchronized preferably in d and S phases with thymine-2-deoxyriboside and colchicines. The adhesive molecule integrinβ1 expresses a high level in SMMC-7721 cells and shows differences in various cell cycles, suggesting integrin β1 plays an important role in adhesion to endothelial cells. The change of adhesive forces in different cell cycle SMMC-7721 cells indicates that S phase cells play predominant roles possibly while they interact with endothelial cells.

Pingyangmycin-regulated Expressions of Adhesion Molecules in Human Venous Malformation Endothelial Cells

Pingyangmycin (bleomycin A5 hydrochloride,PYM) is one of the anti-neoplastic agents which have been commonly used to treat venous malformations.However,the underlying mechanism by which PYM treats venous malformations remains poorly understood.It was reported that venous endothelial cells could recruit neutrophils via adhesion molecules (E-selectin,ICAM-1,ICAM-3,VCAM-1) during the acute/chronic inflammation and subsequent histological fibrosis after sclerotherapy with PYM.This study explored if the expression of E-selectin,ICAM-1,ICAM-3 and VCAM-1 in human venous malformation endothelial cells could be affected by PYM.HVMECs were cultured from human venous malformation tissue.Expressions of E-selectin,ICAM-1,ICAM-3 and VCAM-1 on HVMECs in response to PYM were analyzed by cell ELISA.The relative levels of mRNA expression in the cells were semi-quantified.The results showed that PYM up-regulated the expressions of E-selectin,ICAM-3,VCAM-1 and ICAM-1 in both time-and concentration-dependent manner.Our findings suggested that PYM could induce the expression of adhesion molecules in HVMECs,which might be a possible mechanism by which sclerotherapy by intralesional injection of PYM treats venous malformations.

TIR/BB-loop mimetic AS-1 protects vascular endothelial cells from injury induced by hypoxia/reoxygenation

Morphological and functional abnormalities of vascular endothelial cells(VECs) are risk factors of ischemiareperfusion in skin flaps.Signaling pathway mediated by interleukin-1 receptor(IL-1 R) is essential to hypoxia/reoxygenation(H/R) injury of VECs.While the TIR/BB-loop mimetic(AS-1) disrupts the interaction between IL-1 R and myeloid differentiation primary-response protein 88(MyD88),its role in the VECs dysfunction under H/R is unclear.In this study,we first showed that there was an infiltration of inflammatory cells and the apoptosis of VECs by using a skin flap section from patients who received flap transplantation.We then showed that the H/R treatment induced apoptosis and loss of cell migration of endothelial cell line H926 were attenuated by AS-1.Furthermore,our data suggested that AS-1 inhibits the interaction between IL-1 R and MyD88,and subsequent phosphorylation of IκB and p38 pathway,as well as the nuclear localization of NF-κB subunit p65/p50.Thus,this study indicated that the protective role of AS-1 in H/R induced cellular injury may be due to the AS-1 mediated down-regulation of IL-1 R signaling pathway.

Nerve bundle formation during the promotion of peripheral nerve regeneration:collagenⅥ-neural cell adhesion molecule 1 interaction

The formation of nerve bundles,which is partially regulated by neural cell adhesion molecule 1(NCAM1),is important for neural network organization during peripheral nerve regeneration.However,little is known about how the extracellular matrix(ECM)microenvironment affects this process.Here,we seeded dorsal root ganglion tissue blocks on different ECM substrates of peripheral nerve ECM-derived matrixgel,Matrigel,laminin 521,collagen I,and collagen IV,and observed well-aligned axon bundles growing in the peripheral nerve ECM-derived environment.We confirmed that NCAM1 is necessary but not sufficient to trigger this phenomenon.A protein interaction assay identified collagen VI as an extracellular partner of NCAM1 in the regulation of axonal fasciculation.Collagen VI interacted with NCAM1 by directly binding to the FNIII domain,thereby increasing the stability of NCAM1 at the axolemma.Our in vivo experiments on a rat sciatic nerve defect model also demonstrated orderly nerve bundle regeneration with improved projection accuracy and functional recovery after treatment with 10 mg/m L Matrigel and 20μg/m L collagen VI.These findings suggest that the collagen VI-NCAM1 pathway plays a regulatory role in nerve bundle formation.This study was approved by the Animal Ethics Committee of Guangzhou Medical University(approval No.GY2019048)on April 30,2019.

Expression changes of nerve cell adhesion molecules L1 and semaphorin 3A after peripheral nerve injury

The expression of nerve cell adhesion molecule L1 in the neuronal growth cone of the central nervous system is strongly associated with the direction of growth of the axon, but its role in the regeneration of the peripheral nerve is still unknown. This study explored the problem in a femoral nerve section model in rats. L1 and semaphorin 3A m RNA and protein expressions were measured over the 4-week recovery period. Quantitative polymerase chain reaction showed that nerve cell adhesion molecule L1 expression was higher in the sensory nerves than in motor nerves at 2 weeks after injury, but vice versa for the expression of semaphorin 3A. Western blot assay results demonstrated that nerve cell adhesion molecule L1 expression was higher in motor nerves than in the sensory nerves at the proximal end after injury, but its expression was greater in the sensory nerves at 2 weeks. Semaphorin 3A expression was higher in the motor nerves than in the sensory nerves at 3 days and 1 week after injury. Nerve cell adhesion molecule L1 and semaphorin 3A expressions at the distal end were higher in the motor nerves than in the sensory nerves at 3 days, 1 and 2 weeks. Immunohistochemical staining results showed that nerve cell adhesion molecule L1 expression at the proximal end was greater in the sensory nerves than in the motor nerves; semaphorin 3A expression was higher in the motor nerves than in the sensory nerves at 2 weeks after injury. Taken together, these results indicated that nerve cell adhesion molecules L1 and semaphorin 3A exhibited different expression patterns at the proximal and distal ends of sensory and motor nerves, and play a coordinating role in neural chemotaxis regeneration.

Re-expression of Cell Adhesion Molecule Inhibits Growth and Induces Apoptosis of Human Pancreatic Cancer Cell Line PANC-1

This study examined the expression of cell adhesion molecule 1 （CADM1） in pancreatic cancer and the possible mechanism. The expression of CADM 1 was detected by immunohistochemistry in tissues of pancreatic cancer, pancreatitis, and normal pancreas. The plasmid pcDNA3.1-Hy- gro（＋）/CADM1 was transfected into PANC-1 cells （a pancreatic cancer cell line）. The expression of CADM1 in the transfected cells was determined by RT-PCR and Western blotting. Cell growth was measured by the MTT method and cell apoptosis by flow cytometry. The results showed that CADM1 was weakly expressed in tissues of pancreatic cancer in contrast to its high expression in normal pancreatic and pancreatitis tissues. The expression level of CADM in pancreatic caner was intensely correlated with the differentiation degree, lymph node metastasis and TNM stages. The growth of CADMl-transfected PANC-1 cells was significantly suppressed in vitro by a G1 cell cycle arrest and apoptosis occurrence. It was concluded that re-expression of CADM1 inhibits the growth of pancreatic cancer cells and induces their apoptosis in vitro. As a tumor suppressor gene, CADM1 plays an important role in the occurrence, progression and metastasis of pancreatic cancer.