Claudin蛋白家族在泌尿系肿瘤中的研究进展北大核心

Claudin蛋白家族是构成细胞紧密连接(tight junctions,TJs)的重要骨架蛋白,在细胞极性、上皮屏障特性、细胞运动性和细胞间的稳定性等方面发挥着关键作用。最近研究发现,Claudin蛋白家族在人类多种肿瘤中都有表达失调,起着癌基因或者抑癌基因的作用。本文综述了近年来Claudin蛋白家族在泌尿系统肿瘤(膀胱癌、前列腺癌、肾癌)中的研究进展。     

Bioinformatic identification of key candidate genes and pathways in axon regeneration after spinal cord injury in zebrafish

Zebrafish and human genomes are highly homologous;however,despite this genomic similarity,adult zebrafish can achieve neuronal proliferation,regeneration and functional restoration within 6–8 weeks after spinal cord injury,whereas humans cannot.To analyze differentially expressed zebrafish genes between axon-regenerated neurons and axon-non-regenerated neurons after spinal cord injury,and to explore the key genes and pathways of axonal regeneration after spinal cord injury,microarray GSE56842 was analyzed using the online tool,GEO2R,in the Gene Expression Omnibus database.Gene ontology and protein-protein interaction networks were used to analyze the identified differentially expressed genes.Finally,we screened for genes and pathways that may play a role in spinal cord injury repair in zebrafish and mammals.A total of 636 differentially expressed genes were obtained,including 255 up-regulated and 381 down-regulated differentially expressed genes in axon-regenerated neurons.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment results were also obtained.A protein-protein interaction network contained 480 node genes and 1976 node connections.We also obtained the 10 hub genes with the highest correlation and the two modules with the highest score.The results showed that spectrin may promote axonal regeneration after spinal cord injury in zebrafish.Transforming growth factor beta signaling may inhibit repair after spinal cord injury in zebrafish.Focal adhesion or tight junctions may play an important role in the migration and proliferation of some cells,such as Schwann cells or neural progenitor cells,after spinal cord injury in zebrafish.Bioinformatic analysis identified key candidate genes and pathways in axonal regeneration after spinal cord injury in zebrafish,providing targets for treatment of spinal cord injury in mammals.     

抗肝癌合剂对人肝癌细胞凋亡及间隙连接通讯功能的影响

目的探讨抗肝癌合剂(IPAH)对人肝癌细胞株SMMC-7721细胞凋亡和间隙连接通讯功能的影响。方法制备抗肝癌合剂含药血清,分为高、中、低剂量组,另设阴性对照组和空白血清对照组。培养人肝癌细胞株SMMC-7721进行体外实验,流式细胞仪检测细胞凋亡情况,荧光漂白恢复实验(FRAP)观察对细胞间隙连接通讯功能的影响。结果抗肝癌合剂中剂量组24、48、72h细胞凋亡率分别为(8.07±1.12)%、(12.04±2.12)%、(17.90±1.74)%;高剂量组24、48、72h细胞凋亡率分别为(11.54±2.23)%、(18.29±2.39)%、(22.90±2.43)%,与阴性对照组[(2.42±1.15)%、(2.98±0.92)%、(3.35±0.67)%]及空白对照组[(3.01±1.07)%、(3.88±0.97)%、(4.09±1.23)%]比较,差异有统计学意义(P均0.01)。抗肝癌合剂低、中、高剂量组荧光恢复率分别为(22.43±2.62)%、(42.73±4.36)%、(49.40±5.13)%,随着时间和剂量增加,荧光恢复率明显增加,组间差异有统计学意义(P均0.01)。结论抗肝癌合剂具有诱导肝癌细胞系SMMC-7721细胞凋亡的作用,呈一定的剂量和时间依赖关系。其作用可能与上调细胞间隙连接通讯功能相关。     

Connexin 36 Mediates Orofacial Pain Hypersensitivity Through GluK2 and TRPA1

Trigeminal neuralgia is a debilitating condition, and the pain easily spreads to other parts of the face. Here, we established a mouse model of partial transection of the infraorbital nerve (pT-ION) and found that the Connexin 36 (Cx36) inhibitor mefloquine caused greater alleviation of pT-ION-induced cold allodynia compared to the reduction of mechanical allodynia. Mefloquine reversed the pT-ION-induced upregulation of Cx36, glutamate receptor ionotropic kainate 2 (GluK2), transient receptor potential ankyrin 1 (TRPA1), and phosphorylated extracellular signal regulated kinase (p-ERK) in the trigeminal ganglion. Cold allodynia but not mechanical allodynia induced by pT-ION or by virus-mediated overexpression of Cx36 in the trigeminal ganglion was reversed by the GluK2 antagonist NS102, and knocking down Cx36 expression in Nav1.8-expressing nociceptors by injecting virus into the orofacial skin area of Nav1.8-Cre mice attenuated cold allodynia but not mechanical allodynia. In conclusion, we show that Cx36 contributes greatly to the development of orofacial pain hypersensitivity through GluK2, TRPA1, and p-ERK signaling.Electronic supplementary materialThe online version of this article (10.1007/s12264-020-00594-4) contains supplementary material, which is available to authorized users.     

抑制细胞间缝隙连接通讯功能对星形胶质细胞缺氧/复氧损伤的保护作用

目的研究抑制细胞缝隙连接通讯功能对星形胶质细胞缺氧/复氧损伤的影响.方法原代培养的新生SD大鼠大脑皮层星形胶质细胞分为正常对照组、空白对照组及细胞缝隙连接抑制剂18-α-甘草次酸和油酸酰胺组.荧光示踪法检测星形胶质细胞的缝隙连接通讯功能; MTT法检测抑制缝隙连接通讯功能对缺氧/复氧损伤星形胶质细胞存活率的影响; Annexin V/碘化丙啶双染流式细胞术及Hoechst 33258荧光染色法检测抑制缝隙连接通讯功能对缺氧/复氧损伤星形胶质细胞凋亡的影响.结果与正常对照组相比, 空白对照组星形胶质细胞缝隙连接通讯功能明显增强( P＜0.01), 细胞存活率明显降低( P＜0.01), 细胞凋亡明显增加( P＜0.01);与空白对照组相比, 18-α-甘草次酸及油酸酰胺可显著降低星形胶质细胞缝隙连接通讯功能(均 P＜0.01), 减轻缺氧/复氧损伤引起的星形胶质细胞存活率的降低(均 P＜0.01), 且可减少缺氧/复氧损伤引起的星形胶质细胞凋亡(均 P＜0.01). 结论抑制细胞间缝隙连接通讯功能对星形胶质细胞缺氧/复氧损伤具有保护作用.     

GDF15 promotes simultaneous astrocyte remodeling and tight junction strengthening at the blood–brain barrier

Perivascular astrocyte processes (PAP) surround cerebral endothelial cells (ECs) and modulate the strengthening of tight junctions to influence blood–brain barrier (BBB) permeability. Morphologically altered astrocytes may affect barrier properties and trigger the onset of brain pathologies. However, astrocyte-dependent mediators of these events remain poorly studied. Here, we show a pharmacologically driven elevated expression and release of growth/differentiation factor 15 (GDF15) in rat primary astrocytes and cerebral PAP. GDF15 has been shown to possess trophic properties for motor neurons, prompting us to hypothesize similar effects on astrocytes. Indeed, its increased expression and release occurred simultaneously to morphological changes of astrocytes in vitro and PAP, suggesting modulatory effects of GDF15 on these cells, but also neighboring EC. Administration of recombinant GDF15 was sufficient to promote astrocyte remodeling and enhance barrier properties between ECs in vitro, whereas its pharmacogenetic abrogation prevented these effects. We validated our findings in male high anxiety-related behavior rats, an animal model of depressive-like behavior, with shrunk PAP associated with reduced expression of the junctional protein claudin-5, which were both restored by a pharmacologically induced increase in GDF15 expression. Thus, we identified GDF15 as an astrocyte-derived trigger of astrocyte process remodeling linked to enhanced tight junction strengthening at the BBB.     

缝隙连接阻断剂对大鼠癫痫后海马涟波振荡能量变化的影响

目的 探讨缝隙连接阻断剂奎宁（quinine，QUIN）、甘珀酸（carbenoxolone，CBX）对癫痫大鼠海马涟波（ripple）振荡能量变化的影响。 方法 24只大鼠随机分为模型组、丙戊酸（valproate sodium，VPA）组、QUIN组和CBX组（n=6）。建立氯化锂-匹罗卡品（pilocarpine，PILO）癫痫持续状态（status epilepticus，SE）大鼠模型，VPA组、QUIN组和CBX组在注射PILO前3 d，分别给予VPA（抗癫痫一线药物）200 mg/kg灌胃、QUIN 50 mg/kg腹腔注射、CBX 50 mg/kg腹腔注射。脑电图分析各组大鼠造模前后及推注水合氯醛（止痫）前后海马ripple振荡能量改变。 结果 造模前，正常大鼠海马CA1、CA3、齿状回区均可见ripple振荡表达。与建模前1 d比较，注射PILO后10 min，各组ripple平均能量表达逐渐增强，模型组、VPA组和CBX组在止痫前达到最高峰，QUIN组在PILO注射后60 min达到最高峰（P<0.05）。止痫后，3个干预组ripple平均能量恢复至正常水平；模型组在止痫后1 h ripple平均能量恢复至正常水平；且各组均持续正常水平至SE后3 d。ripple最大能量的变化趋势与平均能量类似。 结论 ripple振荡能量改变可以作为癫痫发作早期预警的定量指标；发作间期ripple振荡能量对癫痫的发作并无提示作用；缝隙连接阻断剂可下调癫痫发作期ripple振荡能量。     

Gap Balancing vs. Measured Resection Technique in Total Knee Arthroplasty

A goal of total knee arthroplasty is to obtain symmetric and balanced flexion and extension gaps. Controversy exists regarding the best surgical technique to utilize to obtain gap balance. Some favor the use of a measured resection technique in which bone landmarks, such as the transepicondylar, the anterior-posterior, or the posterior condylar axes are used to determine proper femoral component rotation and subsequent gap balance. Others favor a gap balancing technique in which the femoral component is positioned parallel to the resected proximal tibia with each collateral ligament equally tensioned to obtain a rectangular flexion gap. Two scientific studies have been performed comparing the two surgical techniques. The first utilized computer navigation and demonstrated a balanced and rectangular flexion gap was obtained much more frequently with use of a gap balanced technique. The second utilized in vivo video fluoroscopy and demonstrated a much high incidence of femoral condylar lift-off (instability) when a measured resection technique was used. In summary, the authors believe gap balancing techniques provide superior gap balance and function following total knee arthroplasty.     

The effect of retinal pigment epithelial cell patch size on growth factor expression

The spatial organization of retinal pigment epithelial (RPE) cells grown in culture was controlled using micropatterning techniques in order to examine the effect of patch size on cell health and differentiation. Understanding this effect is a critical step in the development of multiplexed high throughput fluidic assays and provides a model for replicating disease states associated with the deterioration of retinal tissue during age-related macular degeneration (AMD). Microcontact printing of fibronectin on polystyrene and glass substrates was used to promote cell attachment, forming RPE patches of controlled size and shape. These colonies mimic the effect of atrophy and loss-of-function that occurs in the retina during degenerative diseases such as AMD. After 72 h of cell growth, levels of vascular endothelial growth factor (VEGF), an important biomarker of AMD, were measured. Cells were counted and morphological indicators of cell viability and tight junction formation were assessed via fluorescence microscopy. Up to a twofold increase of VEGF expression per cell was measured as colony size decreased, suggesting that the local microenvironment of, and connections between, RPE cells influences growth factor expression leading to the initiation and progression of diseases such as AMD.     

Difficult esophageal atresia: Trick and treat

Although most patients with esophageal atresia (EA) and tracheo-esophageal fistula (TEF) may benefit from “standard” management, which is deferred emergency surgery, some may present unexpected elements that change this paradigm. Birth weight, associated anomalies, and long gap can influence the therapeutic schedule of the patients with EA/TEF and can make their treatment tricky. As a consequence, detailed information on these aspects gives the power to develop a decision-making process as correct as possible. In this article, we will review the most important factors influencing the treatment of patients with EA/TEF and will share our experience on the diagnostic and therapeutic tips that may provide pivotal help in the management of such patients.