山茱萸多糖对衰老大鼠晶状体中Sirt1基因表达的影响

目的：初步探讨山茱萸多糖治疗年龄相关性白内障的可能机制，为其预防和治疗寻找新的药物和靶点。方法：选用60只昆明大鼠，按体质量随机分为3组，每组20只，分别为对照组（C组）、衰老模型组（A组）和山茱萸多糖给药组（D组）。在相同环境下，C组正常饮食，每日颈背部皮下注射0．9％氯化钠注射液，剂量计算参照其他给药组D-半乳糖给药量；A和D组正常饮食，每日颈背部皮下注射D-半乳糖100mg／（kg·d）；连续皮下注射45d后，C和A组每日按照等剂量灌药量灌服温开水；D组按照多糖0．4g／蛞灌服山莱萸多糖，连续灌服30d。试验终期颈椎离断术处死大鼠，4℃迅速取眼分离晶状体置于液氮备用。免疫组化方法检测各组间总超氧化物歧化酶（T-SOD）和总抗氧化能力（T-AOC）的变化，RT—PCR（逆转录cDNA的聚合酶链式扩增反应）检测各组Sirt1、p53和FOXO1 mRNA的表达变化。结果：A组和D组大鼠晶状体中Sirt1 mRNA的表达较C组均显著上升（P〈0．05、P〈0．01），且D组较A组显著上升（P〈0．01）；A组和D组大鼠晶状体中p53 mRNA的表达较C组显著上升（P均〈0．01），而D组较A组显著下降（P〈0．05）；A组和D组大鼠晶状体中FOXO1 mRNA的表达较C组显著上升（P〈0．05、P〈0．01），且D组较A组显著上升（P〈0．01）。另外A组和D组大鼠晶状体中T—SOD的活性较C组显著上升（P均〈0．01），且D组较A组显著上升（P〈0．01）；A纽和D组大晶状体中鼠T-AOC的活性较C组显著上升（P均〈0．01），且D较A组显著上升（P〈0．01）。结论：山茱萸多糖可能通过调节Sirt1的表达，从而调节下游基因p53和FOXO1的表达，最终抑制或延缓晶状体上皮细胞的凋亡，减缓年龄相关性白内障的进展。     

干燥综合征中抗M3R抗体的研究进展

干燥综合征(Sjgren’s syndrome,SS)是一种以侵犯外分泌腺为主的自身免疫性疾病,其发病机制可能与抗毒蕈碱乙酰胆碱3受体抗体(anti-M3R antibody,抗M3R抗体)相关,本文通过抗M3R抗体与毒蕈碱乙酰胆碱3受体(M3R)的结合表位,以及与SS的临床表现、治疗的关系,对抗M3R抗体在SS中的致病作用进行综述。     

n-3 Polyunsaturated fatty acid supplementation restored impaired memory and GABAergic synaptic efficacy in the hippocampus of stressed rats

While chronic stress induces dendritic atrophy in the hippocampus and impairs learning and memory, supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA) is known to improve learning and memory of control rats. Whether n-3 PUFA supplementation improves dendritic morphology, synaptic transmission, and memory of chronically stressed rats remains unknown. In this work, we randomly assigned male Sprague-Dawley rats in four experimental groups: two unsupplemented groups, control and stress, and two supplemented groups with n-3 PUFA (DHA and EPA mix), control?+?n-3 PUFA and stress?+?n-3 PUFA. Dendritic morphology and synaptic transmission in the hippocampus were evaluated by Golgi stain and patch-clamp tools, respectively. The Y-maze and Morris water maze were used to analyze the effects of chronic stress on memory. Supplementation with n-3 PUFA improved dendritic architecture and restored the frequency of inhibitory post-synaptic currents of hippocampal pyramidal neurons of rats from stress group. In addition, n-3 PUFA supplementation improved spatial memory. Our results demonstrate that n-3 PUFA supplementation had three beneficial effects on stressed rats: prevented or compensated dendritic atrophy in CA3; restored the probability of GABA release in CA1; and improved spatial memory. We argue that n-3 PUFA supplementation can be used in treating stress-related psychiatric disorders such as depression and anxiety.