Caffeine induces neurobehavioral effects through modulating neurotransmitters

Evidence demonstrates that chronic caffeine exposure, primarily through consumption of coffee or tea, leads to increased alertness and anxiety. Preclinical and clinical studies showed that caffeine induced beneficial effects on mood and cognition. Other studies using molecular techniques have reported that caffeine exhibited neuroprotective effects in animal models by protecting dopaminergic neurons. Moreover, caffeine interacts with dopaminergic system, which leads to improvements in neurobehavioral measures in animal models of depression or attention deficit hyperactivity disorder (ADHD). Glutamatergic receptors have been found to be involved on the neurobiological effects of caffeine. Additionally, caffeine has been found to suppress the inhibitory (GABAergic) activity and modulate GABA receptors. Studies have also found that modulating these neurotransmitters leads to neurobehavioral effects. The linkage between the modulatory role of caffeine on neurotransmitters and neurobehavioral effects has not been fully discussed. The purpose of this review is to discuss in detail the role of neurotransmitters in the effects of caffeine on neurobehavioral disorders.     

牛磺酸对海藻氨酸致痫大鼠海马谷氨酸转运体功能的影响

目的　研究海藻氨酸 (KA )致痫后海马神经元谷氨酸转运体 (Glu Ts)的功能变化 ,观察牛磺酸(Tau)对 KA点燃及点燃后海马神经元 Glu Ts功能的影响。方法　将 4 0只 Wistar大鼠随机分为对照组 ( 组 )、KA组 ( 组 )、Tau低剂量组 ( 组 )、Tau高剂量组 ( 组 ) ,每组各 10只。 组和 组分别腹腔注射低剂量 (1g/kg)和高剂量 (2 g/ kg) Tau,每日 1次 ,第 3天注射后 0 .5小时 ,与 KA组一起腹腔注射 KA10 mg/ kg,对照组腹腔注射生理盐水 (NS) 1m l。观察各组的痫性发作情况 ,并于 2 4小时后将大鼠处死 ,剥离右侧海马 ,制备海马突触颗粒 ,测定其摄取 3H- L -谷氨酸的功能。结果　与对照组相比 ,KA组点燃后海马神经元 Glu Ts功能降低 (P<0 .0 1) ;与KA组相比 , 、 组的点燃潜伏期延长 ,点燃率、痫性发作分级及死亡率均降低 ,海马神经元 Glu Ts功能增强 ,其作用与剂量呈正相关。结论　 KA可造成海马神经元 Glu Ts功能降低 ,Tau可抑制 KA引起的癫痫发作 ,其原因可能部分与改善海马神经元 Glu Ts功能有关。     

Dose-dependent effects of prenatal ethanol exposure on synaptic plasticity and learning in mature offspring

BACKGROUND: We have observed profound deficits in hippocampal synaptic plasticity and one-trial learning in offspring whose mothers drank moderate quantities of ethanol during pregnancy. In the present study, we examined the question of whether lower maternal blood ethanol concentrations (BECs) could produce functional deficits in offspring. METHODS: Rat dams consumed either a 2%, 3%, or 5% ethanol liquid diet throughout gestation. Three other groups of dams were pair-fed a 0% ethanol liquid diet, and a seventh group consumed lab chow ad libitum. Adult offspring from each diet group were assigned either to studies of evoked [3H]-D-aspartate (D-ASP) release from hippocampal slices or spatial learning studies using the Morris Water Task. RESULTS: Consumption of the 2%, 3%, and 5% ethanol liquid diets produced mean peak maternal BECs of 7, 30 and 83 mg/dL, respectively. Consumption of these ethanol diets had no effect on offspring birthweight, litter size or neonatal mortality. Likewise, evoked D-ASP release from hippocampal slices and performance on a standard version of the Morris Water Task were not affected by prenatal ethanol exposure. By contrast, activity-dependent potentiation of evoked D-ASP release from slices and one-trial learning on a "moving platform" version of the Morris Water Task were markedly reduced in offspring whose mothers consumed the 5% ethanol liquid diet. Intermediate deficits in these two parameters were observed in offspring from the 3% ethanol diet group, whereas offspring from the 2% ethanol diet group were not statistically different than controls. CONCLUSIONS: We conclude that the threshold for eliciting subtle, yet significant learning deficits in offspring prenatally exposed to ethanol is less than 30 mg/dL. This BEC is roughly equivalent to drinking 1 to 1.5 ounces of ethanol per day.     

成人晚发自身免疫性糖尿病的特点及诊断要点探讨

为加强临床医师对成人晚发自身免疫性糖尿病（ＬＡＤＡ）的认识，本研究比较了ＬＡＤＡ２５例、胰岛素依赖型糖尿病５７例（儿童发病２１例、成人酮症发病３６例）、非胰岛素依赖型糖尿病３８例（轻至中度３０例、重度８例）及正常人４２例的临床、空腹血糖、血浆Ｃ肽水平及ＨＬＡ－ＤＱＡ１、－ＤＱＢ１链基因频率，提出ＬＡＤＡ的特点及诊断要点为：（１）２０～４８岁发病，发病时多饮、多尿、多食症状明显，体重下降快，体重指数（ＢＭＩ）≤２５，空腹血糖≥１６．５ｍｍｏｌ／Ｌ；（２）空腹血浆Ｃ肽≤０．４ｎｍｏｌ／Ｌ，早晨空腹１００ｇ馒头餐后１小时或（和）２小时Ｃ肽≤０．８ｎｍｏｌ／Ｌ；（３）谷氨酸脱羧酶抗体阳性；（４）ＨＬＡ－ＤＱＢ１链第５７位点为非天门冬氨酸纯合子基因（易感基因）。第（１）点是基本临床特点，加上第（２）、（３）、（４）点中任何一点就考虑诊断ＬＡＤＡ，尽早采用饮食、运动及胰岛素治疗，使空腹及三餐后血糖、糖化血红蛋白（ＨｂＡ１ｃ）控制到正常水平，以保护受自身免疫破坏的胰岛Ｂ细胞功能，有利于防止糖尿病眼、肾、神经并发症。     

代谢型谷氨酸受体7对人胚胎神经干细胞增殖的影响

目的 研究代谢型谷氨酸受体7(mGluR7)对人胚胎神经干细胞增殖的影响。方法 利用MTT比色法分析mGluR7过表达载体、mGluR7siRNA在不同时间对体外的人胚胎NSCs细胞活力的影响, 神经球测量方法分析mGluR7对人神经球生长的影响, 流式细胞术分析mGluR7对人NSCs细胞周期及细胞凋亡的影响。结果 MTT结果表明在处理24 h, 48 h和72 h后, mGluR7显著增强人NSCs的细胞活力, 增殖细胞数量显著增多, 神经球直径显著增大, mGluR7siRNA抑制人神经球的增殖。过表达mGluR7后, 与对照组相比G1/G0期和细胞比率显著下降, S期细胞比率显著上升, mGluR7过表达促进了细胞G1到S期转化, 沉默mGluR7将人NSCs细胞阻滞在G1/G0期。应用流式细胞术分析过表达mGluR7对人NSCs细胞凋亡的影响, 转染48 h后, 早凋晚凋均显著下降, 沉默mGluR7能够显著诱导人NSCs的早凋和晚凋。结论 mGluR7可促进体外培养的人胚胎皮质NSCs增殖。     

谷氨酸能系统障碍与卒中后抑郁

近年来,大量研究表明谷氨酸能系统障碍可能与卒中后抑郁（PSD）的发病机制密切相关。本文主要从外周血小板功能障碍、海马神经元再生及重塑障碍两方面阐述谷氨酸能系统障碍在PSD病理生理机制中发挥的作用。     

Evaluation of adjunctive perampanel in patients with refractory partial‐onset seizures: Results of randomized global phase III study 305

Purpose: To assess the efficacy and safety of once‐daily doses of perampanel 8 and 12 mg when added to 1–3 concomitantly administered, approved antiepileptic drugs (AEDs) in patients with uncontrolled partial‐onset seizures. Methods: Study 305 was a multicenter, double‐blind, placebo‐controlled trial in patients aged 12 years and older with ongoing seizures despite prior therapy with at least two AEDs, and currently receiving 1–3 AEDs. Equal randomization to once‐daily oral perampanel 8 or 12 mg, or placebo was performed. Patients entered a 19‐week double‐blind treatment phase comprising a 6‐week titration period, with weekly 2‐mg dose increments, followed by a 13‐week maintenance period. Primary efficacy end points were the responder rate (proportion of patients who had a ≥50% reduction in seizure frequency during treatment per 28 days relative to baseline), and the percent change in seizure frequency per 28 days relative to pre‐perampanel baseline. A secondary end point was percent change in the frequency of complex partial plus secondarily generalized seizures. Adverse events (AEs) were monitored throughout the study. Key Findings: Three hundred eighty‐six patients were randomized and treated with study medication. Of these, 321 patients completed the study. The 50% responder rates (intent‐to‐treat analysis) were 14.7%, 33.3%, and 33.9%, respectively, for placebo, perampanel 8 mg, and perampanel 12 mg, with significant improvements over placebo for both perampanel 8 mg (p = 0.002) and 12 mg (p < 0.001). The median percent change from baseline in seizure frequency per 28 days (intent‐to‐treat analysis) was ?9.7%, ?30.5%, and ?17.6% for placebo, 8 mg, and 12 mg, respectively, with significant reductions compared with placebo for both 8 mg (p < 0.001) and 12 mg (p = 0.011). For complex partial seizures plus partial seizures that secondarily generalized, the median percent change in frequency was ?32.7% (8 mg), ?21.9 (12 mg), and ?8.1% (placebo), with significant reductions for both 8 mg (p < 0.001) and 12 mg (p = 0.005). The most frequent (occurring in ≥10% of patients in any treatment group) treatment‐emergent AEs were dizziness, somnolence, fatigue, and headache, with an apparent dose effect suggested for all except headache. Significance: This phase III trial demonstrated that adjunctive treatment with once‐daily perampanel at 8 mg and 12 mg was effective in improving seizure control in patients 12 years and older with refractory partial‐onset seizures. These study results also demonstrated that once‐daily doses of 8 mg and 12 mg were safe and acceptably tolerated in this study. Perampanel demonstrated a favorable risk/benefit ratio in this population.