Cooperative effects of bcl-2 and AAV-mediated expression of CNTF on retinal ganglion cell survival and axonal regeneration in adult transgenic mice

We used a gene therapy approach in transgenic mice to assess the cooperative effects of combining anti-apoptotic and growth-promoting stimuli on adult retinal ganglion cell (RGC) survival and axonal regeneration following intraorbital optic nerve injury. Bi-cistronic adeno-associated viral vectors encoding a secretable form of ciliary neurotrophic factor and green fluorescent protein (AAV-CNTF-GFP) were injected into eyes of mice that had been engineered to over-express the anti-apoptotic protein bcl-2. For comparison this vector was also injected into wildtype (wt) mice, and both mouse strains were injected with control AAV encoding GFP. Five weeks after optic nerve injury we confirmed that bcl-2 over-expression by itself promoted the survival of axotomized RGCs, but in contrast to previous reports we also saw regeneration of some mature RGC axons beyond the optic nerve crush. AAV-mediated expression of CNTF in adult retinas significantly increased the survival and axonal regeneration of RGCs following axotomy in wt and bcl-2 transgenic mice; however, the effects were greatest in the transgenic strain. Compared with AAV-GFP-injected bcl-2 mice, RGC viability was increased by about 50% (mean, 36 738 RGCs per retina), and over 1000 axons per optic nerve regenerated 1-1.5 mm beyond the crush. These findings exemplify the importance of using a multifactorial therapeutic approach that enhances both neuroprotection and regeneration after central nervous system injury.     

红景天苷对骨骼肌保护作用机制的研究进展

红景天作为一味珍贵的药材,研究发现其在治疗心血管疾病、肿瘤疾病、老年疾病、肾脏疾病、骨骼肌营养不良、呼吸疾病等方面均有不同功效。而红景天苷作为红景天的主要药效成分,具有抗缺氧、抗炎、抗疲劳、抗寒、强心、抗心律失常等多种药理作用。就红景天苷在骨骼肌中的保护作用机制研究进展进行综述。     

Neuroprotective effects of cold-inducible RNA-binding protein during mild hypothermia on traumatic brain injur y

Cold-inducible RNA-binding protein(CIRP), a key regulatory protein, could be facilitated by mild hypothermia in the brain, heart and liver. This study observed the effects of mild hypothermia at 31 ± 0.5℃ on traumatic brain injury in rats. Results demonstrated that mild hypothermia suppressed apoptosis in the cortex, hippocampus and hypothalamus, facilitated CIRP m RNA and protein expression in these regions, especially in the hypothalamus. The anti-apoptotic effect of mild hypothermia disappeared after CIRP silencing. There was no correlation between mitogen-activated extracellular signal-regulated kinase activation and CIRP silencing. CIRP silencing inhibited extracellular signal-regulated kinase-1/2 activation. These indicate that CIRP inhibits apoptosis by affecting extracellular signal-regulated kinase-1/2 activation, and exerts a neuroprotective effect during mild hypothermia for traumatic brain injury.     

中药在防治帕金森病中的作用及研究进展

帕金森病(Parkinson’s disease,PD)是常见的神经系统退行性疾病,随着世界人口老龄化,发病率逐年增高,给社会、家庭和个人造成沉重的负担。中药以其毒副作用小、协同作用强和整体调节等优势,为PD的中药防治提供了良好前景。该文从抗氧化应激和抗神经细胞凋亡两个方面,对近10年来中药单体或有效成分,在PD防治方面的研究进展进行了综述。     

中耳胆脂瘤上皮细胞的抗凋亡机制

近年来,有关中耳胆脂瘤的发生与细胞凋亡状态的研究受到广泛关注。最新研究表明胆脂瘤上皮细胞凋亡受到抑制在中耳胆脂瘤的发生和发展中起着重要作用。本文对相关抗凋亡因子在中耳胆脂瘤中的表达进行了综述,并着重介绍了PI3K-Akt/PKB和MAPK两个抗凋亡信号转导通路及其在胆脂瘤上皮细胞抗凋亡机制中的作用。     

幽门螺杆菌对胆管癌细胞增殖与凋亡及细胞核转录因子NF-KB表达的影响

目的探讨幽门螺杆菌（Hp）对人类胆管癌细胞增殖和凋亡的影响,以及该影响的细胞内信号转导途径。方法用CCK-8（Cell Counting Kit-8）法和流式细胞仪法检测Hp对胆管癌细胞增殖、凋亡及细胞周期分布的影响,利用免疫细胞化学和凝胶电泳迁移率变动实验（EMSA）分析细胞核转录因子NF-KB在Hp作用前后的表达活化情况;使用特异性NF-KB阻断剂吡咯烷二硫氨基甲酸酯（PDTC）阻断NF-KB的活化,利用细胞免疫化学技术和RT-PCR半定量技术分析比较抗凋亡蛋白Bcl-2和Bcl-XL在转录因子NF-KB失活前后的表达情况。结果在MOI值（细菌与细胞浓度比）为0.5∶1的状态下,Hp对QBC939细胞有促增殖作用,第1、3d的增殖率分别为（15.24±4.2）%和（34.18±2.6）%,差异具有统计学意义（P〈0.05）。在该MOI值时无诱导细胞凋亡作用,但可推动细胞周期的进展;在此过程中伴有细胞NF-KB活化和抗凋亡蛋白Bcl-2、Bcl-XL表达上调;PDTC阻断实验证明抗凋亡蛋白Bcl-2和Bcl-XL的表达受到NF-KB活性的调控。结论幽门螺杆菌—核转录因子NF-KB抗凋亡蛋白Bcl-2、Bcl-XL传导通路的活化在胆管癌细胞的增殖、凋亡及恶性转化中可能具有重要作用。     

Survivin与妇科肿瘤关系的研究进展

Survivin是新近发现的一种凋亡抑制基因,其不仅具有凋亡抑制作用,而且对细胞分裂和血管形成起重要作用.Survivin在胚胎发育过程及人体的多数肿瘤组织中均有大量表达,但在大多数正常终末分化组织中无表达;在常见的妇科肿瘤组织中表达也有升高,且其在肿瘤组织中的表达与肿瘤的临床分期、组织学分级及预后有关,并与肿瘤耐药性相关,可望成为肿瘤治疗的基因靶.Survivin的作用机制目前仍不清楚,该文对其生物学作用及在常见妇科肿瘤中的表达情况作以综述.