单侧外周伤害性刺激诱发大鼠脊髓中转录因子CREB的双侧磷酸化(英文)

c AMP反应成分结合蛋白 (c AMP response elem ent-binding protein,CREB)是一种转录因子 ,它在磷酸化之后可调节靶基因的转录。 CREB在 13 3位置的丝氨酸的磷酸化 ,与脊髓中伤害性传入的处理有关 ,本文作者等用特殊抗体对此进行了免疫细胞化学研究。在正常大鼠 ,虽然几乎所有脊髓神经元的核中都可见 CREB的轻度着色 ,但磷酸化的 CREB仅见于双侧腰段脊髓的 ～ 层 (75± 15 vs60± 18)和 层 (9± 3 )。用福尔马林注射引起一侧后脚掌出现炎症时 ,可在双侧腰段脊髓看到磷酸化CREB细胞核的快速 (小于 5 min)和节段性的显著增多 ;它们主要分布在双侧背角表层 ～ 层 (2 5 4± 2 0 vs 2 62± 2 3 )、 层(115± 13 )和双侧 ～ 层 (3 46± 2 0 vs3 2 8± 2 6) ;而在对照和炎症组大鼠的胸段脊髓中均未见磷酸化 CREB的增加。在注射CFA诱发一侧炎症或切断一侧坐骨神经的实验组大鼠 ,也可看到至少延续到第三天的强而双侧性的 CREB的磷酸化。这种由一侧后肢伤害性传入引致腰段脊髓中镜像式双侧 CREB磷酸化的出现 ,与一般看到的损伤传入只在同侧脊髓背角引起某些神经化学改变的结果不同 ,可能是人神经损伤后或在实验动物中出现对侧镜像式疼痛过敏现象的基础     

Effect of high-BDNF microenvironment stem cells therapy on neurogenic bladder model in rats

BackgroundThe purpose of this study is to explore the effects of high-BDNF microenvironment produced by engineered immortalized mesenchymal stem cells (imMSCs) on the neurogenic bladder (NB) and investigate underlying mechanism.MethodsMale Sprague-Dawley rat (12-week-old, weighing about 370–400 g) were purchased from a Korean company (Orient Bio Co. Seongnam, Korea) and divided into the following groups (n=32): sham control group (n=8), NB group (n=8), NB + ImMSCs group (n=8), NB + ImMSCs (BDNF) group (n=8). The major pelvic ganglion (MPG) was observed under anesthesia. Three NB groups of rats were then subjected to bilateral MPG injury. The sham control group of rats was treated with sham surgery. Cystometry were performed before the rats were sacrificed, and then MPG and bladder were collected for histochemical and Western blot analysis.ResultsMSCs treatment improves lower urinary tract function, and the NB + ImMSCs (BDNF) group is better than the NB + ImMSCs group (P<0.01). MSCs treatment accelerates recovery of injured nerve tissue, and the NB + ImMSCs (BDNF) group is better than the NB + ImMSCs group (P<0.01). In high BDNF environment, apoptosis was reduced more significantly and muscle tissue recovered more rapidly (P<0.01). High-BDNF microenvironment activates more BDNF/TrkB/CREB signaling pathways (P<0.01).ConclusionsIn a rat NB model caused by nerve injury, imMSCs have certain effects on nerve tissue repair. At the same time, it was proved that increasing the expression of BDNF which had specific effect on nerve injury repair could more effectively repair injured MPG in local microenvironment. The mechanism may be related to the activation of the BDNF/TrkB/CREB signaling pathway and the reduction of apoptosis by highly expressed BDNF.     

Hypothalamic insulin and glucagon-like peptide-1 levels in an animal model of depression and their effect on corticotropin-releasing hormone promoter gene activity in a hypothalamic cell line

Background

In depression, excessive glucocorticoid action may cause maladaptive brain changes, including in the pathways controlling energy metabolism. Insulin and glucagon-like peptide-1 (GLP-1), besides regulation of glucose homeostasis, also possess neurotrophic properties. Current study was aimed at investigating the influence of prenatal stress (PS) on insulin, GLP-1 and their receptor (IR and GLP-1R) levels in the hypothalamus. GLP-1 and GLP-1R were assayed also in the hippocampus and frontal cortex – brain regions mainly affected in depression. The second objective was to determine the influence of exendin-4 and insulin on CRH promoter gene activity in in vitro conditions.