Increased body sway at 3.5-8 Hz in patients with phobic postural vertigo

Gicerin is an integral membrane glycoprotein which mediates cell-cell and cell-extracellular matrix (ECM) interactions in the nervous system. We studied gicerin expression in the hypoglossal nucleus post transection using in situ hybridization and immunocytochemistry. We found that hypoglossal nerve injury resulted in a significant increase in gicerin expression. Its expression levels reached peak values in reactive astrocytes surrounding axotomized motoneurons of the ipsilateral hypoglossal nucleus 14 days after hypoglossal nerve injury. The results indicate that gicerin is up-regulated during nerve regeneration, suggesting that gicerin expressed in the reactive astrocytes might be involved in the processes of nerve regeneration.     

Monoclonal antibody against SSEA-1 is specific for a subpopulation of astrocytes in mouse cerebellum

Monoclonal antibody to SSEA-1 reacts specifically in the mouse cerebellum with the cell surface of a subclass of estrocytes, but not of neurons, oligodendrocytes, fibroblasts and fibroblast-like cells, or macrophages. The antigen is weakly detectable on cultured cells by indirect immunofluorescence at embryonic day 13 after one day of maintenance in vitro, and strongly detectable in glial fibriallary acidic protein- and vimentin-positive astrocytes throughout later embryonic and early postnatal ages. In histological sections SSEA-1 is found at embryonic day 14 in the ventricular zones of the cerebellar anlage and at early postnatal ages in prospective while matter tracts and external granular and molecular layers. It continues to be detectable in these regions until the fourth postnatal week, when its expression becomes restricted to weakly positive, dot-like structures in the molecular layer.     

Changes in state of the glia in different parts of the rat brain after systemic circulatory arrest

Institute of General Resuscitation, Russian Academy of Medical Sciences, Moscow. (Presented by Academician A. V. Negovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 8, pp. 176–179, August, 1992.     

短暂性前脑缺血再灌流60天后海马区cGMP及GFAP的反应

观察脑缺血 5 min后再灌流 6 0 d的海马区 c GMP及 GFAP反应细胞的分布。钳夹沙土鼠的双侧颈总动脉制造脑缺血模型 ,应用免疫荧光组织化学方法。结果表明 ,CA1 区锥体细胞层出现一些 c GMP及 GFAP阳性细胞 ,双重免疫荧光反应证实c GMP阳性细胞为星形胶质细胞。齿状回与海马本部不同 ,较对照组增加了一些中、小圆形的 c GMP阳性细胞分布在齿状回的多形细胞层。本研究结果提示 ,增生的星形胶质细胞 c GMP反应阳性 ,c GMP与星形胶质细胞关系密切 ,c GMP可能在脑缺血再灌流中扮演着重要角色     

小鼠血脑屏障的组织发生

探讨脑内毛细管的生长发育与形态结构和功能的关系。方法：用透射电镜对３５只不同发育时期小鼠血脑屏障建立过程中的超微结构及血管密度进行了分析，结果：胚胎第１５、１８天血管密度较低，出生后第一天血管度增长明显，第７天下降，以后随年龄增长管密度逐渐增加。     

星形胶质细胞缝隙连接在脑缺血再灌注损伤中的研究进展

缺血性脑血管病（ischemic cerebrovascular disease,ICVD）在临床疾病中属于常见的一类疾病,在脑血管疾病中占比约有70% 以上。胶质细胞在神经系统中的数量是最多的,远超过神经元。星形胶质细胞的线粒体功能发生障碍,导致神经元在存活和发挥正常的生理功能方面出现问题。缝隙连接蛋白（connexin,CX）是执行这个功能的关键蛋白,CX 构成了缝隙连接通道,在病理过程中发挥了重要作用。该文综述了星形胶质细胞的缝隙连接蛋白43 对脑缺血发挥保护作用的研究进展。     

氯胺酮体外对星形胶质细胞表面脑保护相关受体表达的影响

目的:观察消旋体氯胺酮体外对星形胶质细胞表面谷氨酸转运体1(glial glutamate transporter-1,GLT-1)、Na~+-K~+泵和生长相关蛋白43(growth associated protein-43,GAP-43)表达的影响,探讨氯胺酮作用于星形胶质细胞的可能作用机制。方法:建立离体培养的原代星形胶质细胞。选取MK-801及AP-5作为对照药物,采用蛋白质印迹法观察氯胺酮处理不同时间后,星形胶质细胞表面GLT-1、Na~+-K~+泵及GAP-43蛋白表达的变化。同时检测星形胶质细胞乳酸脱氢酶(lactate dehydrogenase,LDH)漏出率,观察氯胺酮处理30 min～24 h对细胞的毒性作用。结果:经氯胺酮处理30 min、2 h的星形胶质细胞表面GLT-1表达量较空白组明显增加(P0.05)。经氯胺酮处理15、30 min及MK-801处理6 h的星形胶质细胞表面Na~+-K~+泵的表达量较空白组明显增加(P0.05)。经氯胺酮及MK-801处理6、24 h的星形胶质细胞表面GAP-43表达量较空白组明显减少(P0.05)。终浓度分别为100、1、50μmol/L的氯胺酮、MK-801、AP-5持续作用24 h后,离体培养原代星形胶质细胞的LDH漏出率与空白组差异无统计学意义。结论:消旋体氯胺酮可通过非N-甲基-D-天冬氨酸(NMDA)途径体外上调星形胶质细胞表面GLT-1、Na~+-K~+泵表达;100μmol/L氯胺酮持续作用24 h对离体培养的原代星形胶质细胞无明显损伤。     

Morphometric analysis of astrocytes in vocal production circuits of common marmoset (Callithrix jacchus)

Astrocytes, the star-shaped glial cells, are the most abundant non-neuronal cell population in the central nervous system. They play a key role in modulating activities of neural networks, including those involved in complex motor behaviors. Common marmosets (Callithrix jacchus), the most vocal non-human primate (NHP), have been used to study the physiology of vocalization and social vocal production. However, the neural circuitry involved in vocal production is not fully understood. In addition, even less is known about the involvement of astrocytes in this circuit. To understand the role, that astrocytes may play in the complex behavior of vocalization, the initial step may be to study their structural properties in the cortical and subcortical regions that are known to be involved in vocalization. Here, in the common marmoset, we identify all astrocytic subtypes seen in other primate's brains, including intralaminar astrocytes. In addition, we reveal detailed structural characteristics of astrocytes and perform morphometric analysis of astrocytes residing in the cortex and midbrain regions that are associated with vocal production. We found that cortical astrocytes in these regions illustrate a higher level of complexity when compared to those in the midbrain. We hypothesize that this complexity that is expressed in cortical astrocytes may reflect their functions to meet the metabolic/structural needs of these regions.     

Andrographolide relieved pathological pain generated by spared nerve injury model in mice

Context: Andrographolide (Andro), found in large quantities in Andrographis paniculata Nees (Acanthaceae), is anti-inflammatory, especially in the central nervous system (CNS) glia.

Objective: The objective of this study is to test Andro’s ability to reduce allodynia in a spared nerve injury model.

Material and methods: Male 30?g BalbC mice were divided into four groups: (1) Sham-operated control (Sham-group); (2) nerve injured and treated with saline (Saline-group); (3) nerve injured and treated with Andro (Andro-group); (4) nerve injured and treated with non-steroidal anti-inflammatory drugs (NSAIDS) (NSAIDS-group). Andro or NSAIDS (diclofenac salt) were injected intraperitoneally at 5?mg/kg body weight daily. Mechanical allodynia was assessed by von Frey tests at 3, 7, and 14?d. For immunohistochemical analysis, samples were collected at 7?d.

Results: The threshold for inducing allodynia increased and the response percentage reduced in the Andro-group when compared with the Saline-group, as well as when compared with NSAIDS groups throughout 3–14?d. The ratio of threshold for OP-Andro/OP-saline and for OP-Andro/OP-NSAIDS groups was 20.42 and 11.67 at 14?d, respectively. The ratio of response percentage for OP-Andro/OP-saline and for OP-Andro/OP-NSAIDS was 0.32 and 0.39 at 14?d, respectively. Interleukin-1 (IL-1) immunostaining in the spinal cord was reduced in the Andro-group. Astrocytic activities were not significantly reduced in the Andro-group compared with the Saline-group at 7?d post-operation (PO)

Conclusions: Andro reduced mechanical allodynia more than NSAIDS at the same concentration, and the observed behaviour was associated with a reduction in inflammatory cytokine produced in the spinal cord.     

Potential neuroprotective role of astroglial exosomes against smoking-induced oxidative stress and HIV-1 replication in the central nervous system

Introduction: HIV-1-infected smokers are at risk of oxidative damage to neuronal cells in the central nervous system by both HIV-1 and cigarette smoke. Since neurons have a weak antioxidant defense system, they mostly depend on glial cells, particularly astrocytes, for protection against oxidative damage and neurotoxicity. Astrocytes augment the neuronal antioxidant system by supplying cysteine-containing products for glutathione synthesis, antioxidant enzymes such as SOD and catalase, glucose for antioxidant regeneration via the pentose-phosphate pathway, and by recycling of ascorbic acid.

Areas covered: The transport of antioxidants and energy substrates from astrocytes to neurons could possibly occur via extracellular nanovesicles called exosomes. This review highlights the neuroprotective potential of exosomes derived from astrocytes against smoking-induced oxidative stress, HIV-1 replication, and subsequent neurotoxicity observed in HIV-1-positive smokers.

Expert opinion: During stress conditions, the antioxidants released from astrocytes either via extracellular fluid or exosomes to neurons may not be sufficient to provide neuroprotection. Therefore, we put forward a novel strategy to combat oxidative stress in the central nervous system, using synthetically developed exosomes loaded with antioxidants such as glutathione and the anti-aging protein Klotho.