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.     

SLC18A3 promoted renal cancer development through acetylcholine/cAMP signaling

Renal cancer displays a high metastatic potential and a poor response to chemotherapy. However, the critical contributors to renal cancer development remain elusive. This study focused on acetylcholine (ACh) signaling. We identified the vesicular acetylcholine transporter (SLC18A3) that upregulates in patients with renal cancer. We further discovered that SLC18A3 enhanced the uptake of ACh, a classical neurotransmitter mediating synaptic transmission. The elevated ACh activated the protein kinase A (PKA)/cAMP-response element binding protein (CREB) pathway, which contributed to renal cancer cell proliferation and invasive migration. Consistently, SLC18A3 overexpression caused sustained tumor growth and increased lung metastases in A489-bearing mice. In summary, our study demonstrated that SLC18A3 contributed to cancer spread in an ACh/PKA/CREB-dependent manner, which may drive the design of efficacious treatment strategies.     

天然脑活素的记忆改善效果及其分子机理研究

目的:研究中药古方强记汤及天然脑活素对记忆障碍动物模型在记忆改善方面的作用效果;并运用转基因技术进一步验证天然脑活素对学习记忆分子开关CREB基因表达的促进作用。方法:将强记汤及天然脑活素分别以29.3g/kg和18.6g/kg的量每日经口灌胃给予SPF级小鼠,连续5d,第6天给药1h后制备成记忆障碍模型,第7天给药0.5~1h后分别用跳台法和避暗法测试记忆成绩;另用不同剂量(50g/mL和150g/mL)天然脑活素水煎液处理大鼠大脑B104CNS神经细胞,以荧光素酶方法检测CREB表达水平。结果:强记汤及天然脑活素水煎液对动物记忆障碍模型小鼠记忆成绩中的潜伏时间、错误次数与模型对照组比较均有统计学意义(P<0.01);而且天然脑活素的改善效果明显优于原方(P<0.01);不同剂量天然脑活素水煎液CREB表达水平与对照组比较有统计学意义(P<0.01),且有剂量反应关系。结论:中药古方强记汤及天然脑活素对实验动物被动回避反应能力的记忆获得、记忆保持及记忆再现均有的改善作用,能显著增加在B104CNS神经元细胞中CREB基因的表达。     

褪黑素抗大鼠吗啡奖赏效应的表达与脑内CREB及其磷酸化

目的:观察褪黑素(melatonin,Mel)对大鼠吗啡诱导的条件性位置偏爱(CPP)效应表达的影响及此过程中脑内cAMP反应元件结合蛋白(CREB)及其磷酸化的变化。方法:(1)大鼠连续6 d给予吗啡(sc,5 mg.kg-1/d)建立CPP模型,于CPP测试前20 min ip Mel(50和25 mg.kg-1),观察Mel对大鼠吗啡诱导的CPP效应表达的影响。(2)大鼠同上建立吗啡CPP模型,d7上、下午,d8上午ip Mel 50 mg.kg-1,共3次,最后一次ip后6 h,采用免疫组化结合计算机图像处理技术测定脑内伏隔核、海马内CREB及磷酸化CREB(p-CREB)的免疫阳性反应强度。结果:Mel 50 mg.kg-1可显著翻转大鼠吗啡诱导的CPP评分升高(P<0.01),同时显著降低吗啡诱导的大鼠伏隔核、海马内p-CREB的上调(P<0.01)。结论:Mel抑制大鼠吗啡奖赏效应的表达,此作用可能与其抑制吗啡诱导的伏隔核、海马内p-CREB蛋白水平上调有关。     

Deoxyactein Isolated from Cimicifuga racemosa protects osteoblastic MC3T3‐E1 cells against antimycin A‐induced cytotoxicity

Deoxyactein is one of the major constituents isolated from Cimicifuga racemosa. In the present study, we investigated the protective effects of deoxyactein on antimycin A (mitochondrial electron transport inhibitor)‐induced toxicity in osteoblastic MC3T3‐E1 cells. Exposure of MC3T3‐E1 cells to antimycin A caused significant cell viability loss, as well as mitochondrial membrane potential dissipation, complex IV inactivation, ATP loss, intracellular calcium ([Ca²⁺]_i) elevation and oxidative stress. Pretreatment with deoxyactein prior to antimycin A exposure significantly reduced antimycin A‐induced cell damage by preventing mitochondrial membrane potential dissipation, complex IV inactivation, ATP loss, [Ca²⁺]_i elevation and oxidative stress. Moreover, deoxyactein increased the activation of PI3K (phosphoinositide 3‐kinase), Akt (protein kinase B) and CREB (cAMP‐response element‐binding protein) inhibited by antimycin A. All these data indicate that deoxyactein may reduce or prevent osteoblasts degeneration in osteoporosis or other degenerative disorders. Copyright © 2011 John Wiley & Sons, Ltd.     

β-榄香烯对神经病理性疼痛模型大鼠神经功能及ERK，CREB，BDNF表达的影响

目的观察β-榄香烯对神经病理性疼痛模型大鼠神经功能保护及对模型大鼠脊髓背根神经节ERKmRNA、CREBmRNA、BDNFmRNA表达的的影响。方法建立神经病理性疼痛大鼠模型,对各组大鼠进行热痛觉过敏行为测试;RealtimePCR检测模型大鼠脊髓背根神经节ERKmRNA、CREBmRNA．以及BDNFmRNA表达。结果假手术组无明显神经功能障碍;与模型组比较,中药组（β-榄香烯）能明显上调模型大鼠热板及机械刺激后的痛阈（P〈0．05或0．01）,且ERKmRNA、CREBmRNA以及BDNFmRNA的表达较模型组明显上调（P〈0．05或0．01）。结论β-榄香烯可改善模型大鼠热痛觉,上调神经病理性疼痛模型大鼠脊髓背根神经节ERKmRNA、CREBmRNA、BDNFmRNA表达从而促进神经元修复。     

大补元煎通过上调BDNF/TrkB/CREB信号通路改善APP/PS1双转基因痴呆小鼠海马突触可塑性

目的:观察大补元煎对APP/PS1痴呆小鼠海马突触可塑性及脑源性神经营养因子(BDNF)/酪氨酸蛋白激酶受体B(TrkB)/环磷酸腺苷反应元件结合蛋白(CREB)信号通路的作用,并探讨其改善突触可塑性的可能机制。方法:将APP/PS1小鼠36只分为模型组、多奈哌齐组(6.5×10~(-4)g·kg~(-1)·d~(-1))和大补元煎组(13.2 g·kg~(-1)·d~(-1)),野生鼠12只设为正常组,正常组和模型组给予等体积生理盐水,各组连续灌胃30 d。应用Morris水迷宫检测各组小鼠的学习记忆能力,应用尼氏染色和高尔基染色观察海马区神经元和突触的病理形态变化,应用免疫荧光(IF)观察海马突触后致密蛋白95(PSD95)及突触素(SYN)的蛋白表达水平,采用蛋白免疫印迹法(Western blot)检测海马中BDNF,TrkB,CREB及磷酸化CREB(p-CREB)的蛋白表达水平。结果:与空白组比较,模型组小鼠平台潜伏期和游泳总路程增加(P0.01),穿越平台次数和目标象限停留时间减少(P0.01),小鼠海马CA3区神经元胞内尼氏体减少或消失,小鼠海马CA3区神经元及树突分支数量、树突棘密度减少(P0.01),小鼠海马SYN,PSD95,BDNF,TrkB及p-CREB的蛋白表达水平减少(P0.01)。与模型组比较,多奈哌齐组和大补元煎组小鼠平台潜伏期和游泳总路程减少(P0.05,P0.01),穿越平台次数和目标象限停留时间增加(P0.05,P0.01),小鼠海马CA3区神经元胞内尼氏体数量增多,小鼠海马CA3区神经元及树突分支数量,树突棘密度增加(P0.05,P0.01),小鼠海马SYN,PSD95,BDNF,TrkB及p-CREB的蛋白表达水平增加(P0.05,P0.01)。结论:大补元煎改善APP/PS1双转基因小鼠突触可塑性的机制可能与其上调小鼠海马中BDNF/TrkB/CREB信号通路有关。