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Objective:To evaluate the role of Sirtuin 1/nuclear factor κB (SIRT1/NF-κB) signaling pathway in mild hypothermia-induced promotion of microglial polarization during oxygen-glucose deprivation and restoration (OGD/R).Methods:The well-grown BV2 microglia were divided into 4 groups ( n=36 each) using the random number table method: control group (group C), OGD/R group (group O), mild hypothermia group (group M), and mild hypothermia+ SIRT1 specific inhibitor EX527 group (group ME). Cells in group C were commonly cultured without any treatment. Cells in group O were subjected to 3 h of OGD followed by 21 h of restoration of O 2-glucose supply at 37 ℃. Cells in group M were subjected to 3 h of OGD followed by 21 h of restoration of O 2-glucose supply at 33 ℃. Cells in group ME were co-cultured with inhibitor EX527 (final concentration 5 nmol/L) for 12 h in the medium before OGD/R, and the other procedures were conducted as previously described in group M. The cell survival rate was detected by CCK-8 assay. The levels of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and interleukin-10 (IL-10) in supernatant were detected by enzyme-linked immunosorbent assay. The expression of CD206, CD32, inducible nitric oxide synthase (iNOS) and arginine synthase 1 (Arg-1) mRNA was detected by quantitative real-time polymerase chain reaction. The expression of CD206 and CD32 was detected by immunofluorescent staining. The expression of iNOS, Arg-1, SIRT1, NF-κB p65 (p65) and acetylated NF-κB (Ac-p65) was detected by Western blot. Results:Compared with group C, the cell survival rate was significantly decreased, the concentrations of TNF-α, IL-6 and IL-10 in the supernatant were increased, the expression of CD206, Arg-1, CD32 and iNOS was up-regulated, the expression of SIRT1 was down-regulated, and the Ac-p65/p65 ratio was increased in group O ( P<0.05). Compared with group O, the cell survival rate was significantly increased, the concentrations of TNF-α and IL-6 in the supernatant were decreased, the concentration of IL-10 was increased, the expression of CD206, Arg-1 and SIRT1 was up-regulated, the expression of CD32 and iNOS was down-regulated, and the Ac-p65/p65 ratio was decreased in group M ( P<0.05). Compared with group M, the cell survival rate was significantly decreased, the concentrations of TNF-α and IL-6 in the supernatant were increased, the concentration of IL-10 was decreased, the expression of CD206, Arg-1 and SIRT1 was down-regulated, the expression of CD32 and iNOS was up-regulated, and the Ac-p65/p65 ratio was increased in group ME ( P<0.05). Conclusions:SIRT1/NF-κB signaling pathway is involved in mild hypothermia-induced promotion of microglial polarization during OGD/R.
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Objective:To evaluate the effect of irisin on the alveolar macrophage polarization in a rat model of ventilator-induced lung injury (VILI).Methods:Thirty SPF healthy adult male Sprague-Dawley rats, aged 6-8 weeks, weighing 200-250 g, were divided into 3 groups ( n=10 each) using a random number table method: control group (group C), VILI group (group V) and irisin group (group I). The rats were mechanically ventilation (tidal volume 20 ml/kg, respiratory rate 80 times/min, inhaled oxygen concentration 21%, inspiratory/expiratory ratio 1∶2, positive end-expiratory pressure 0) for 4 h to develop VILI model.Group C kept spontaneous breathing for 4 h. Irisin 1 μg/kg was injected via the tail vein at 30 min before tracheal intubation in group I, while the equal volume of normal saline was given instead in the other groups.The rats were sacrificed at 4 h of mechanical ventilation, the lung tissues were removed for examination of pathological changes which were scored and for determination of wet to dry weight ratio (W/D ratio), and bronchoalveolar lavage fluid (BALF) was collected for determination of concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and IL-10 (by enzyme-linked immunosorbent assay), expression of inducible nitric oxide synthase (iNOS), argininase 1 (Arg-1), and phosphorylated nuclear factor kappa B (p-NF-κB) p65 and p-NF-κB p50 in alveolar macrophages (by Western blot), and percentage of M1 and M2 alveolar macrophages and M1/M2 ratio (by flow cytometry). Results:Compared with group C, the W/D ratio, lung injury score, and concentrations of IL-6, TNF-α and IL-10 in BALF were significantly increased, the expression of iNOS, Arg-1, p-NF-κB p65 and p-NF-κB p50 was up-regulated, and the percentage of M1 and M2 alveolar macrophages and M1/M2 ratio were increased in group V and group I ( P<0.05). Compared with group V, the W/D ratio, lung injury score, and concentrations of IL-6 and TNF-α in BALF were significantly decreased, the expression of iNOS and p-NF-κB p65 was down-regulated, the percentage of M1 alveolar macrophages and M1/M2 ratio were decreased ( P<0.05), and no significant change was found in levels of IL-10 and Arg-1 in BALF, percentage of M2 alveolar macrophages and expression of p-NF-κB p50 in group I ( P>0.05). Conclusions:The mechanism by which irisin reduces VILI may be related to inhibition of NF-κB signaling pathway activation and reduction of alveolar macrophage polarization to M1 phenotype in rats.
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Objective:To evaluate the role of cathepsin B (CTSB) in mechanical ventilator-induced lung injury (VILI) in rats and the relationship with NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome.Methods:Thirty-six SPF-grade healthy male Sprague-Dawley rats, aged 6-8 weeks, weighing 220-300 g, were divided into 3 groups ( n=12 each) by the random number table method: control group (group C), VILI group (group V) and VILI + CA074-me group (group Me). CA074-me 5 mg/kg was intraperitoneally injected in group Me, while the equal volume of normal saline was given instead in group C and group V. Group C kept spontaneous breathing for 4 h, and the animals were mechanically ventilated (tidal volume 20 ml/kg, respiratory rate 80 breaths/min, fraction of inspired oxygen 21%, PEEP 0 cmH 2O). Blood samples from femoral artery were collected for arterial blood gas analysis before tracheal intubation and after spontaneous breathing or ventilation, and PaO 2 was recorded.Rats were sacrificed, and bronchoalveolar lavage fluid (BALF) was collected and lung tissues were collected for determination of the wet/dry lung weight ratio (W/D ratio), serum interleukin-1beta (IL-1β) and IL-18 concentrations in BALF (by enzyme-linked immunosorbent assay), expression of CTSB, NLRP3, apoptosis-associated speck-like protein containing a caspase-1 recruitment domain (ASC) and caspase-1 mRNA in lung tissues (quantitative real-time polymerase chain reaction), and expression of CTSB, NLRP3, ASC and caspase-1 in lung tissues (by Western blot) and for microscopic examination of the pathological changes (using HE staining). Lung injury was assessed and scored. Results:Compared with group C, PaO 2 was significantly decreased after the end of ventilation, the lung injury score, W/D ratio and concentrations of IL-1β and IL-18 in serum and BALF were increased, and the expression of CTSB, NLRP3, ASC and caspase-1 protein and mRNA in lung tissues was up-regulated in group V and group Me ( P<0.01). Compared with group V, PaO 2 was significantly increased after the end of ventilation, the lung injury score, W/D ratio and concentrations of IL-1β and IL-18 in serum and BALF were decreased, and the expression of CTSB, NLRP3, ASC and caspase-1 protein and mRNA in lung tissues was down-regulated in group Me ( P<0.01). Conclusions:CTSB is involved in VILI in the rats, and the mechanism may be related to activation of NLRP3 inflammasomes.
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Objective:To evaluate the role of miR-188-5p in oxygen-glucose deprivation and restoration (OGD/R) injury to mouse neuroblastoma (N2a) cells and its relationship with small ubiquitin-like modifier-specific proteases 3 (SENP3).Methods:N2a cells were cultured and divided into 5 groups ( n=23 each) using a random number table method: control group (group C), OGD/R group, group NC, transfection of mir-188-5p agonist group (group M) and transfection of mir-188-5p inhibitor group group (group I). Cells in group C were cultured routinely.Cells in group NC, group M and group I were transfected with mir-188-5p negative control miRNA, agonist and inhibitor, respectively.N2a cells were subjected to OGD for 3 h followed by restoration of oxygen-glucose supply to establish the model of OGD/R injury.At 24 h of oxygen-glucose restoration, the cell viability was recorded by the cell counting kit-8 assay, the amount of lactic dehydrogenase (LDH) released was detected, the expression of miR-188-5p and SENP3 mRNA was detected by quantitative real-time polymerase chain reaction, and SENP3 expression was determined by Western blot.The targeting relationship between miR-188-5p and SENP3 mRNA was detected using dual luciferase reporter assay. Results:Compared with group C, the cell viability was significantly decreased, amount of LDH released was increased, and expression of SENP3 and its mRNA was up-regulated in the other 4 groups, miR-188-5p expression was down-regulated in OGD/R and I groups, and miR-188-5p expression was up-regulated in group M ( P<0.05 or 0.01). Compared with group OGD/R, the cell viability was significantly decreased, amount of LDH released was increased, and expression of SENP3 and its mRNA was up-regulated, and miR-188-5p expression was down-regulated in group I, and the cell viability was increased, amount of LDH released was decreased, expression of SENP3 and its mRNA was down-regulated, and miR-188-5p expression was up-regulated in group M ( P<0.05 or 0.01). The dual luciferase reporter assay showed that miR-188-5p could act directly on SENP3. Conclusion:miR-188-5p is involved in OGD/R injury, which is associated with targeted down-regulation of SENP3 expression in N2a cells.
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Objective:To summarize the clinical and imaging features of five patients of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) with cysteine-sparing NOTCH3 gene missense mutations and explore potential pathogenicity of gene mutations.Methods:The clinical data from five patients who were admitted to the People′s Hospital of Zhengzhou University from March 2017 to November 2018 were collected. The patients were found to carry cysteine-sparing NOTCH3 gene mutations through genetic testing and diagnosed pathologically. They were probands confirmed from five unrelated family and all five patients were performed full exon detection and skin biopsy.Results:Genetic testing identified five patients with cysteine-sparing NOTCH3 gene missense mutations, a total of five different mutations, including p.R75Q, p.D80G, p.V237M, p.S1418L and p.R1761H. The first three mutations were found in the epidermal growth factor-like repeats (EGFr), the latter two mutations near the transmembrane domain. Granular osmiophilic material was identified in all cases examined with skin biopsy. The age at initial symptom onset of these five cases was ranged from 22 to 58 years and three cases presented cardiovascular risk factors. The primary clinical manifestations included migraine in one case, ischemic stroke in three cases, psychiatric disturbances in four cases, cognitive dysfunction in five cases, while gait disturbance, pseudobulbar palsy, and seizures accounted for only one case each. Magnetic resonance imaging of five patients all showed white matter hyperintensities (WMLs) and lacunar infarcts, and WMLs involved the anterior temporal pole and external capsules in three cases separately. According to the criteria proposed by Mui?o et al for evaluating the pathogenicity of cysteine-sparing NOTCH3 mutations, all five mutations are potentially pathogenic.Conclusions:Most characteristics of CADASIL patients with cysteine-sparing NOTCH3 gene mutations are similar to those of CADASIL patients with cysteine NOTCH3 gene mutations. Mutations not involving the EGFr may also have potential pathogenicity, and the specific mechanism still needs further study.
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Objective:To evaluate the effect of electroacupuncture (EA) preconditioning on expression of cortical Ubc9 during cerebral ischemia-reperfusion (I/R) in rats.Methods:A total of 80 healthy clean-grade male Sprague-Dawley rats, aged 8-12 weeks, weighing 200-250 g, were divided into 4 groups ( n=20 each) using a random number table method: sham operation group (group S), group I/R, EA preconditioning group (group E) and sham EA group (group SE). Blood vessels were only exposed, without occlusion in group S. In the other three groups, the cerebral I/R model was established by middle cerebral artery occlusion using suture-occluded method, and the suture was removed after 2-h occlusion to restore the perfusion in anesthetized rats.EA was performed at 5 days before establishing the model in group E and group SE.Baihui acupoints were stimulated with an electric stimulator (2/12 Hz disperse-dense waves, intensity 1 mA) for 30 min once a day for 5 consecutive days, and the model was established at 24 h after the last stimulation.EA was performed at the points 1 cm lateral to the acupoints of Baihui, and the other operating parameters were the same as those previously described in group E. Neurological deficit scores (NDSs) were evaluated at 24 and 48 h of reperfusion.Then the rats were sacrificed, and tissues in the ischemic penumbra of cerebral cortex were obtained for determination of cell apoptosis (by TUNEL) and expression of Ubc9 and conjugated small ubiquitin-like modifier (SUMO) 2/3 (by Western blot). The apoptosis rate was calculated. Results:Compared with group S, NDSs at 24 and 48 h of reperfusion and apoptosis rate were significantly increased, and the expression of Ubc9 and conjugated SUMO2/3 was up-regulated in the other three groups ( P<0.05). Compared with group I/R and group SE, NDSs at 24 and 48 h of reperfusion and apoptosis rate were significantly decreased, and the expression of Ubc9 and conjugated SUMO2/3 was up-regulated in group E( P<0.05). Conclusion:The mechanism by which EA preconditioning reduces cerebral I/R injury is related to up-regulating Ubc9 expression and thus enhancing SUMO2/3ylation in rats.
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Objective@#To investigate the value of next-generation sequencing (NGS) technology in the prognosis monitoring and treatment guidance for molecular minimal residual disease (MRD) in acute myeloid leukemia (AML) patients with complete remission (CR).@*Methods@#The clinical data of 68 AML (non-acute promyelocytic leukemia) patients who received gene mutation spectrum by using NGS technology at initial diagnosis and in CR phase in Tangdu Hospital of Air Force Military Medical University from January 2016 to July 2018 were retrospectively analyzed. The recurrence and survival of both molecular MRD positive group and negative group were analyzed and compared, and the value of NGS technology and multiparameter flow cytometry (MFC) were also analyzed in MRD monitoring.@*Results@#There were 39 males (57.4%) and 29 females (42.6%) in 68 patients, and the median age was 52 years old (8-82 years old). Molecular MRD positive group included 38 patients, while negative group included 30 patients. Residual mutation gene type in CR phase was most frequently detected in epigenetic regulator gene mutations, such as ASXL1, TET2, DNMT3A and IDH1/IDH2. Statistical analysis showed that the 2-year cumulative recurrence rate (CIR) in the molecular MRD positive group was higher than that in the molecular MRD negative group (86.8% vs. 51.3%; χ2 = 9.249, P = 0.002); the 2-year relapse-free survival (RFS) rate in the molecular MRD positive group was lower than that in the molecular MRD negative group (13.2% vs. 48.7%; χ2 = 9.249, P = 0.002); the 2-year overall survival (OS) rate in the molecular MRD positive group was lower than that in the molecular MRD negative group (58.0% vs. 100%; χ2 = 4.122, P = 0.042). Up to follow-up date, 3 patients with molecular MRD positive and 1 patient with molecular MRD negative who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) were still in disease-free survival. The results of monitoring MRD showed high consistency (76.7%, 33/43) in NGS and MFC. Compared with the other groups, the patients with both positive NGS and MFC had a higher relapse rate, and the difference was statistically significantly (P < 0.05).@*Conclusions@#Molecular MRD of AML patients is detected by using NGS technology, which could be used to predict the relapse and survival, suggesting that molecular MRD may guide post-remission treatment regimens and the determination of allo-HSCT indications.
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Objective To investigate the value of next-generation sequencing (NGS) technology in the prognosis monitoring and treatment guidance for molecular minimal residual disease (MRD) in acute myeloid leukemia (AML) patients with complete remission (CR). Methods The clinical data of 68 AML (non-acute promyelocytic leukemia) patients who received gene mutation spectrum by using NGS technology at initial diagnosis and in CR phase in Tangdu Hospital of Air Force Military Medical University from January 2016 to July 2018 were retrospectively analyzed. The recurrence and survival of both molecular MRD positive group and negative group were analyzed and compared, and the value of NGS technology and multiparameter flow cytometry (MFC) were also analyzed in MRD monitoring. Results There were 39 males (57.4% ) and 29 females (42.6%) in 68 patients, and the median age was 52 years old (8-82 years old). Molecular MRD positive group included 38 patients, while negative group included 30 patients. Residual mutation gene type in CR phase was most frequently detected in epigenetic regulator gene mutations, such as ASXL1, TET2, DNMT3A and IDH1/IDH2. Statistical analysis showed that the 2-year cumulative recurrence rate (CIR) in the molecular MRD positive group was higher than that in the molecular MRD negative group (86.8% vs. 51.3%;χ 2＝ 9.249, P＝ 0.002); the 2-year relapse-free survival (RFS) rate in the molecular MRD positive group was lower than that in the molecular MRD negative group (13.2% vs. 48.7%; χ2＝ 9.249, P＝ 0.002); the 2-year overall survival (OS) rate in the molecular MRD positive group was lower than that in the molecular MRD negative group (58.0% vs. 100%; χ 2 ＝ 4.122, P＝ 0.042). Up to follow-up date, 3 patients with molecular MRD positive and 1 patient with molecular MRD negative who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) were still in disease-free survival. The results of monitoring MRD showed high consistency (76.7%, 33/43) in NGS and MFC. Compared with the other groups, the patients with both positive NGS and MFC had a higher relapse rate, and the difference was statistically significantly (P < 0.05). Conclusions Molecular MRD of AML patients is detected by using NGS technology, which could be used to predict the relapse and survival, suggesting that molecular MRD may guide post-remission treatment regimens and the determination of allo-HSCT indications.
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Objective To investigate the clinical manifestations,imaging features,molecular genetic characteristics and possible pathogenic mechanisms of hereditary cerebral small vessel disease (CSVD) caused by heterozygous mutation of HtrA serine protease-1 (HTRA1) gene.Methods The clinical data of a Chinese Han family with CSVD carrying a heterozygous mutation of HTRA 1 gene,which came from the Department of Neurology,Henan Provincial People's Hospital in March 2018,were analyzed retrospectively.The clinical and radiographic features were summarized.Several high-throughput whole exon high-throughput sequencing was used to capture the mutation sites and the Sanger sequencing was used to validate the results.The family diagram was drawn and the 3D model construction and mutation function prediction were performed using silico tools.The relevant literature was reviewed and the pathogenesis was explored.Results The pedigree map showed that the family had an autosomal dominant inheritance pattern.Three generations of the family were investigated,and three family members in the same generation suffered from the disease.The first symptom of the proband was diplopia at the age of 39,accompanied by recurrent stroke,cognitive impairment and mood disorders,without alopecia.Head magnetic resonance imaging revealed bilateral diffuse,symmetric lesions,multiple lacunar infarcts,perivascular space,and microbleeds.The elder sister of the proband developed symptoms of left limb weakness at the age of 46,whose other clinical and imaging features were similar to those of the proband.The proband's mother died at the age of 59 due to repeated strokes.Whole exon sequencing indicated heterozygous missense mutation at c.821G＞A locus of HTRA1 gene in the proband and her 4th elder sibling,which was a new pathogenic mutation after consulting several mutation sites of databases.Function prediction suggested pathogenicity.Conclusions The heterozygous mutation of c.821G＞A in HTRA1 gene may lead to autosomal dominant CVSD.This genetic type should be given clinical attention.
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Objective To investigate the safety and efficacy of decitabine combined with CAG regimen in treatment of acute myeloid leukemia (AML) ineligible for conventional chemotherapy. Methods The data of 20 cases with AML ineligible for conventional chemotherapy from January 2013 to May 2015 were retrospectively analyzed. Decitabine combined with CAG regimen was used during induction therapy. The primary induction regimen was used 26 times after remission, the standard 3+7 regimen were used 7 times, and intermediate-dose cytarabine were used 3 times. The total course of treatment included 2-8 cycles. Results All of the 20 patients completed the first cycle of induction therapy, including 11 cases of complete remission (CR), 5 cases of partial remission and no response in 4 cases, and the overall response rate (ORR) was 80 % (16/20). ORR was 69.2 % (9/13) and 100.0 % (7/7) in high-risk group and middle-low risk group respectively. ORR was 60.0%(6/10) in AML evolving from MDS. 8 patients were infected during the induction therapy and the infection rate was 40.0% (8/20). 2 patients were died of pulmonary infection. The median number of suspended red blood cell and platelet infused were (9.1±5.7) U and (57.5±51.9) U respectively. Neutrophil recovery time was (8.7±5.6) days during induction therapy. All patients were followed up for at least 1 year, and 12 cases were dead. Overall survival rate was 85.0%at 3 months, 80.0%at 6 months, and 40.0%at 1 year. While in 12 CR patients relapse-free survival rate was 75.0%at 3 months, 75.0%at 6 months,and 65.6%at 1 year respectively. Conclusion Decitabine combined with CAG regimen with high remission rate and well tolerance, can be used as a first therapy for AML ineligible for conventional chemotherapy.
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The single molecule imaging and technologies that developed in 1990 s have successfully probed the dynamics of single molecule enzyme catalysis in real time in vitro. Ever since then, single molecule enzymology has entered the golden age of rapid developing. Individual features of each enzyme hidden in the overall average have been discovered, and many new catalytic mechanisms have been proposed. Single molecule enzymology sheds light on the dynamic interactions between enzymes and substrates or products, deepening the understanding of biochemical reactions. This review described the recent research progresses of single molecule protease and ribozyme.
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The preservation of urinary proteins on a membrane plays a vital role in biomarker research, and the efficient elution of proteins preserved on nitrocellulose membrane (NC membrane) determines the application of this method. During the heating elution procedure, we raised the temperature to reduce the intense vortexing time, and kept gentle rotating while precipitation to prevent nitrocellulose reformation. We also used SDS-PAGE and LC-MS/MS to analyze the urinary proteins prepared by heating elution procedure, intense vortexing elution procedure and acetone precipitation method. There was no degradation of proteins prepared by heating elution procedure. Compared with proteins prepared by heating elution method and acetone precipitation method, the overlapping rates of the proteins was almost the same (92.6% versus 96.8%) and the ratios of CV values (< 20%) of the proteins were both high (85.2% and 94.4%). The heating elution procedure achieved good technical reproducibility, and was much simpler and more efficient than the previous one. It can facilitate the application of the preservation of urinary proteins on membrane.
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Humans , Acetone , Biomarkers , Urine , Chromatography, Liquid , Collodion , Electrophoresis, Polyacrylamide Gel , Hot Temperature , Proteins , Reproducibility of Results , Tandem Mass Spectrometry , Urine , ChemistryABSTRACT
Objective To establish a stable in vitro model of blood-brain barrier (BBB) simulating in vivo state using the primary-cultured rat brain microvascular endothelial cells (BMVECs) and pericytes.Methods The primary rat BMVECs and pericytes were isolated,purified and cultured.The isolated cells were identified by immunocytochemical staining method.An in vitro model of BBB was constructed using Transwell inserts (pore size 0.4 μm) coculture.Its barrier function was evaluated by the 4-hour leakage test,tight junction protein identification,transendothelial resistance detection,and permeability test.The difference between the cocultured model and simple BMVEC model across the membrane resistance values,and the permeability difference of the small molecule sodium fluorescein (Na-F) were compared.Results Confluent BMVEC monolayers demonstrated a typical cobblestone appearance and the pericytes displayed irregular shape and overlapping growth.Immunodouble labeling technique identification showed that the pericytes positively expressed α-srmooth muscle actin (α-SMA) and neuron-glial antigen 2 (NG2); after the fusion of cocultured model endothelial cells,the surface leakage test became positive; immnocytochemical staining shows that a continuous and dense tight junction formed between the endothelial cells; compared to the BMVEC model,the transendothelial electrical resistance of the cocultured model increased significantly (190.762 ± 10.326 Ω/cm2 vs.96.503 ± 8.012 Ω/cm2; t=- 24.489,P ＜0.01),and the permeability decreased significantly (56.149％ ± 3.572％ of the single endothelial model; t =19.330,P ＜ 0.01 ).Conclusions The primary isolated rat BMVECs and pericytes cocultured the morphology,structure and barrier function of in vitro model have the basic characteristics of BBB,and they have provided a useful tool for the research of BBB.
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Objective To explore the method of primary isolation, cultivation and identification of rat brain microvessel pericytes. Methods The brain tissue of 10 3 week-old Wistar rats was separated sterilely. The brain microvessel fragments were separated using two-step enzyme digestion and one-step gradient centrifugation and were seeded in 35-mm dishes for primary culture. The cell morphology was observed by phase contrast microscopy; the immunofluorescence assay was used to identify the associated antigns, such as the α-smooth muscle actin (α-SMA), neuron-glial antigen 2 (NG2), von Willebrand factor (vWF), and glial fibrillary acidic protein (GFAP). Methyl thiazolyl tetrazolium was used to determine the cell growth curve. Results Pericytes climbed out from the adherent brain microvascular fragments around,showing polygonal, and the cell fusion was 95％ after 12-14 days. Immunofluorescence staining revealed that the molecular markers of the pericytes α-SMA and NG2 related antigens showed double positive, while the vWF and GFAP related antigens showed double negative and the cultured cells were confirmed as brain microvascular pericytes. The growth rate of primary cells was slower. The passage cells entered into logarithmic growth phase after 36 to 60 hours and entered into plateau phase after 72 to 108 hours. Conclusions This method may successfully isolate rat brain microvascular pericytes with higher purity.
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Pericytes are a very important cellular constituent of the blood-brain barrier.They play a regulatory role in brain angiogenesis,endothelial cell tight junction formation,blood-brain barrier differentiation,microvascular dynamic motion and structural stability.Pericytes exhibit unique functional characteristics in some diseases,such as cerebrovascular disease,neurodegenerative disease,neuroimmune disease and traumatic brain injury.This article reviews the roles of pericytes in the blood-brain barrier.