[Establishment of a system for regulating the gene expression of embryonic mouse cerebral cortex neural stem cells by in utero electroporation]. / å­å®«å† ç”µç©¿å­”æ³•è°ƒæŽ§é¼ èƒšå¤§è„‘çš®è´¨ç¥žç»å¹²ç»†èƒžåŸºå› è¡¨è¾¾ä½“ç³»çš„å»ºç«‹.

OBJECTIVES: To establish a system for regulating the gene expression of embryonic mouse cerebral cortex neural stem cells (NSCs) using in utero electroporation (IUE). METHODS: At embryonic day 14.5, the mouse cerebral cortex NSCs were electro-transfected with the pCIG plasmid injected into the ventricle of the mouse embryo. At embryonic day 16.5 or day 17.5, embryonic mouse brain tissues were collected to prepare frozen sections. Immunofluorescence staining was used to observe the proliferation, apoptosis, division, directional differentiation, migration, and maturation of NSCs. RESULTS: The differentiation of NSCs into intermediate progenitors, the proliferation and apoptosis of NSCs, and the morphological development of radial axis of radial glial cells were observed at embryonic day 16.5. The differentiation of NSCs into neurons in layers V-VI of the cerebral cortex, the migration of NSCs to the lateral cerebral cortex, the development of dendrites of migrating neurons, and the maturation of neurons were observed at embryonic day 17.5. CONCLUSIONS: The system for regulating the gene expression of embryonic mouse cerebral cortex NSCs can be established using IUE, which is useful for the study of neural development related to the proliferation, apoptosis, division, directional differentiation, migration and maturation of NSCs in the cerebral cortex.

[Expression of TGF-ß1 and PAI-1 in premature infants with bronchopulmonary dysplasia].

OBJECTIVE: To study the expression of transforming growth factor-ß1 (TGF-ß1) and plasminogen activator inhibitor-1 (PAI-1) and its significance in premature infants with bronchopulmonary dysplasia (BPD). METHODS: A retrospective analysis was performed on the clinical data of 96 very low birth weight infants (gestational age of ≤ 32 weeks) who survived for more than 28 days and were admitted to the Neonatal Intensive Care Unit between January 2010 and December 2012. These subjects were divided into BPD group (n=21) and non-BPD group (n=75). The expression of TGF-ß1 and PAI-1 in blood was measured by ELISA. RESULTS: The levels of TGF-ß1 and PAI-1 in the BPD group increased gradually from the 7th day to the 14th day and then to the 21st day after birth, and were significantly higher than in the non-BPD group at all time points (P<0.01). The TGF-ß1 and PAI-1 levels in the non-BPD group on the 7th, 14th, and 21st days after birth were not significantly different from each other (P>0.05). CONCLUSIONS: The expression of TGF-ß1 and PAI-1 in blood is elevated in premature infants with BPD, which may be associated with the development of BPD.

Effect of Probenecid on Endothelial Cell Growth Rate and Retinal Angiogenesis in an Oxygen-Induced Retinopathy Model.

Objectives: Probenecid is an anion transport inhibitor, which, according to the connectivity map (CMap; a biological application database), interferes with hypoxia-induced gene expression changes in retinal vascular endothelial cells (ECs). Here, we investigated the influence of probenecid on retinal EC cytotoxicity and retinal neovascularization in a murine oxygen-induced retinopathy (OIR) model. Methods: The retinal EC growth rate in the presence of hypoxia-mimicking concentrations of cobalt chloride (CoCl2) was determined using the thiazolyl blue tetrazolium bromide (MTT) assay and proliferating cell nuclear antigen (PCNA) expression. In OIR rats, probenecid was administered by intraperitoneal injection (i.p.) from postnatal day (P) 1 to P7. The concentrations of vitreous humor vascular endothelial growth factor (VEGF), hypoxia-inducible factor (HIF)-1α, and placental growth factor (PlGF) were determined by using the ELISA kit at P21. The amount of newly formed vascular lumen was evaluated by histopathological examination. Retinopathy and neovascularization were assessed by scoring isolectin B4 fluorescein-stained retinal flat mounts. Western blots for liver tissue HIF-1α and hepcidin (HAMP) were performed. Results: In vitro, probenecid led to the recession of the hypoxia-induced EC growth rate. In vivo, compared to the OIR retina, the upregulation of VEGF, HIF-1α, and PlGF in phase II retinopathy of prematurity (ROP) was inhibited by probenecid administration. Moreover, probenecid ameliorated neovascularization and resulted in significantly reduced relative leakage fluorescence signal intensity in fluorescein-stained retinal flat mounts (p < 0.05). Probenecid alleviated the liver overactivation of HAMP and downregulation of HIF-1α in OIR rats. Conclusions: This is the first demonstration that implies that probenecid might be a protective compound against retinal angiogenesis in OIR. These changes are accompanied with decreased hyperoxia-mediated hepcidin overproduction. Although the relevance of the results to ROP needs further research, these findings may help establish potential pharmacological targets based on the CMap database.

The Effect of STAT3 Signal Pathway Activation on Retinopathy of Prematurity.

Objective: To investigate the mechanism of activation of the signal transducer and activator of transcription 3 (STAT3) signal pathway in the process of retinopathy of prematurity (ROP). Methods: Sixty newborn Sprague-Dawley (SD) rats were randomly separated into the hyperoxia and air control groups (n = 30/in each group). The serum hepcidin level on 21 d was measured using the enzyme-linked immunosorbent assay (ELISA). The expression of HAMP and STAT3 protein in the liver was determined using reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. Retinal neovasculature was evaluated by hematoxylin and eosin (HE) stain and fluorescein lectin. The retinal endothelial cells were treated with 250 µmol/L cobalt chloride for 72 h and added S3I-201. The STAT3 level was determined by western blotting. Results: The expression of STAT3 protein increased significantly after hyperoxia stimulation. The expression of HAMP mRNA in the hyperoxia group was significantly higher than that of the control group. The proliferation of retinal cells was inhibited, and the expression of STAT3 was increased. No significant difference was noted in vascular endothelial growth factor (VEGF) mRNA. The expression of STAT3 and VEGF mRNA was significantly reduced. Conclusion: The activation of the STAT3 signal pathway increased hepcidin expression, contributing to the pathogenesis of ROP. S3I-201 inhibited the expression of STAT3 and VEGF mRNA levels. This information provides potential novel therapeutic approach to the prevention and treatment of ROP.

In vitro neurotoxicity by ropivacaine is reduced by silencing Cav3.3 T-type calcium subunits in neonatal rat sensory neurons.

Neurotoxicity of local anaesthetics has been alerted by more and more peoples. Cav3.1 and Cav3.2 T-type calcium channels were closely related with local anaesthetics toxicity. However, the role of Cav3.3, another subtype of the T-type calcium channel, on the neurotoxicity induced by local anaesthetics remains unclear. CaMKIIγ is a kind of multifunctional kinase and associated with a variety of physiological and pathological process. T-type calcium channel is closely related with CaMKIIγ. Up-regulation CaMKIIγ can increase T-type currents at the dorsal root ganglia (DRG). On the contrary, down-regulation results in the T-type currents decrease. Is the relation between Cav3.3 T-type channel calcium and CaMKIIγ involved with the ropivacaine hydrochloride neurotoxicity? In this study, we generated pAd-Cav3.3 and pAd-shRNA adenovirus vector to up-regulate and down-regulate Cav3.3 mRNA expression of the DRG. The cells treated or untreated with ropivacaine hydrochloride (3 mM) for 4 h were used to evaluate the neurotoxicity. Cell viability, cell death rate and apoptosis rate, Cav3.3 and CaMKIIγ expression were detected with MTT method, Hoechst-PI, flow cytometry, qRT-PCR and western blotting. Results showed that the cell viability of the DRG treated with ropivacaine hydrochloride markedly decreased, death rate and apoptosis rate, Cav3.3 and CaMKIIγ mRNA and protein expression significantly increased. Cav3.3 overexpression aggravated DRG injury induced by ropivacaine hydrochloride and inhibition of Cav3.3 expression improved the cell damages. Cav3.3 can regulate CaMKIIγ mRNA and protein expression. In conclusion, Cav3.3 regulated CaMKIIγ in DRG, which was involved with the cell injury induced by ropivacaine hydrochloride.

TAK1 as the mediator in the protective effect of propofol on renal interstitial fibrosis induced by ischemia/reperfusion injury.

Ischemia-reperfusion injury (IRI), which is a major cause of acute and chronic renal dysfunction, induces both apoptosis and fibrotic processes. The mitogen-activated protein kinase kinase kinase transforming growth factor-ß-activated kinase 1 (TAK1) was implicated in the processes of inflammation and fibrosis. The protective effect of propofol on renal functionality after acute kidney injury (AKI) in mice has been identified, whereas the mechanisms underlying fibrosis induced by kidney injury remain obscure. Herein, we investigated whether the protective effect of propofol on renal interstitial fibrosis induced by ischemia/reperfusion injury was modulated by TAK1 in renal ischemia /reperfusion (I/R) mouse models. The results of immunohistochemistry and western blotting revealed that TAK1 was significantly upregulated in IR group versus the control group, which was reversed by propofol administration. In addition, fibronectin (FN), α-smooth muscle actin (α-SMA) and type I collagen (COL1) were significantly downregulated and Tunnel staining revealed the number of tubular apoptotic cells was markedly reduced in IRP group versus IR group. Collectively, our results validated that propofol could ameliorate the IRI-induced renal interstitial fibrosis in mice by downregulation of TAK1 and inhibition of apoptosis at the early stage.