排序方式: 共有5条查询结果,搜索用时 0 毫秒
1
1.
Li-Ying Liu Feng Wang Xia-Yan Zhang Peng Huang Yun-Bi Lu Er-Qing Wei Wei-Ping Zhang 《PloS one》2012,7(10)
Nicotinamide phosphoribosyltransferase (NAMPT) is a key enzyme for nicotinamide adenine dinucleotide (NAD) biosynthesis, and can be found either intracellularly (iNAMPT) or extracellularly (eNAMPT). Studies have shown that both iNAMPT and eNAMPT are implicated in aging and age-related diseases/disorders in the peripheral system. However, their functional roles in aged brain remain to be established. Here we showed that upon aging, NAMPT level increased in serum but decreased in brain, decreased in cortex and hippocampus but remained unchanged in cerebellum and striatum in brain, and increased in microglia but likely decreased in neuron. Accordingly, total NAD (tNAD) level significantly decreased in hippocampus, cerebellum and striatum in aged brain. Application of recombinant NAMPT, mimicking the elevated serum NAMPT level, enhanced the susceptibility of cerebral endothelial cells to ischemic injury, while inhibition of iNAMPT by FK866, a specific inhibitor, reduced intracellular NAD level and induced neuronal death. Taken together, we have revealed a region- and cell-specific change of NAMPT level in brain and serum upon aging, deduced its potential consequences, which suggests that NAMPT is a regulatory factor in aging and age-related brain diseases. 相似文献
2.
脱氧雪腐镰刀菌烯醇对胃癌细胞增殖及细胞周期的影响 总被引:2,自引:0,他引:2
探讨脱氧雪腐镰刀菌烯醇(DON)对体外培养的两株胃癌细胞(SGC-7901和BGC-823)增殖及细胞周期的影响。采用细胞培养、噻唑蓝(MTF)比色法、流式细胞定量检测(FCM)、蛋白质免疫印迹(Western印迹)以及免疫细胞化学染色(ICH)等方法,研究不同浓度DON处理72h对体外培养胃癌细胞的增殖、细胞周期及细胞周期相关蛋白—细胞周期蛋白依赖性激酶抑制蛋白(CKIs)P21WAF/CIP1和细胞周期蛋白E(cyclin E)表达的影响。MTT法检测结果显示DON可明显抑制两株胃癌细胞的增殖,SGC.7901和BGC.823细胞100、500、1000ug/L DON处理组的增殖抑制率分别为4.28%、36.20%、45.35%和14.89%、32.30%、51.61%。FCM检测结果显示,给予1000ug/LDON处理72h可使两株细胞周期阻滞在GffM期。在100~1000u扎浓度范围内,两株细胞P21WAF/CIP1表达量均高于对照组,P21WAF/CIP1的表达与DON浓度呈显著正相关关系(SGC-7901细胞:r=0.886,P〈0.01;BGC-823细胞:r=0.943,P〈0.01);两株细胞的细胞周期蛋白E表达量均低于对照组,与DON浓度有明显剂量依赖关系(SGC.7901细胞:r=-0.923,P〈0.01;BGC-823细胞:r=-0.854,P〈0.01)。Western印迹及免疫细胞化学检测进一步证实了DON处理对蛋白质表达的影响。综合结果表明,DON可抑制体外培养胃癌细胞的增殖活性,G2/M期阻滞、P21WAF/CIP1表达增高及细胞周期蛋白E表达下降可能是DON抑制胃癌细胞增殖的可能机制,DON对分化程度不同的胃癌细胞的影响没有明显差别。 相似文献
3.
Bing Zhao Meng Zhang Xue Han Xia-Yan Zhang Qiong Xing Xu Dong Qiao-Juan Shi Peng Huang Yun-Bi Lu Er-Qing Wei Qiang Xia Wei-Ping Zhang Chun Tang 《PloS one》2013,8(12)
Intracellular nicotinamide phosphoribosyltransferase (iNAMPT) in neuron has been known as a protective factor against cerebral ischemia through its enzymatic activity, but the role of central extracellular NAMPT (eNAMPT) is not clear. Here we show that eNAMPT protein level was elevated in the ischemic rat brain after middle-cerebral-artery occlusion (MCAO) and reperfusion, which can be traced to at least in part from blood circulation. Administration of recombinant NAMPT protein exacerbated MCAO-induced neuronal injury in rat brain, while exacerbated oxygen-glucose-deprivation (OGD) induced neuronal injury only in neuron-glial mixed culture, but not in neuron culture. In the mixed culture, NAMPT protein promoted TNF-α release in a time- and concentration-dependent fashion, while TNF-α neutralizing antibody protected OGD-induced, NAMPT-enhanced neuronal injury. Importantly, H247A mutant of NAMPT with essentially no enzymatic activity exerted similar effects on ischemic neuronal injury and TNF-α release as the wild type protein. Thus, eNAMPT is an injurious and inflammatory factor in cerebral ischemia and aggravates ischemic neuronal injury by triggering TNF-α release from glia cells, via a mechanism not related to NAMPT enzymatic activity. 相似文献
4.
Juan Yu Bing Xie Ge-Yue Bi Hui-Hui Zuo Xia-Yan Du Li-Fang Bi Dong-Mei Li Hua-Xiang Rao 《PLoS neglected tropical diseases》2022,16(6)
The aim of this study was to investigate the occurrence and molecular characteristics of Bartonella infections in small rodents in the Shangdang Basin, China. Small rodents were captured using snap traps, and their liver, spleen, and kidney tissues were harvested for Bartonella detection and identification using a combination of real-time PCR of the ssrA gene (296 bp) and conventional PCR and sequencing of the gltA gene (379 bp). Results showed that 55 of 147 small rodents to be positive for Bartonella, with a positivity rate of 37.41%, and 95% confidence interval of 29.50%- 45.33%. While the positivity rate across genders (42.62% in males and 33.72% in females, χ2 = 1.208, P = 0.272) and tissues (28.57% in liver, 33.59% in spleen, and 36.76% in kidney, χ2 = 2.197, P = 0.333) of small rodents was not statistically different, that in different habitats (5.13% in villages, 84.44% in forests, and 54.17% in farmlands, χ2 = 80.105, P<0.001) was statistically different. There were 42 Bartonella sequences identified in six species, including 30 B. grahamii, three B. phoceensis, two B. japonica, two B. queenslandensis, one B. fuyuanensis and four unknown Bartonella species from Niviventer confucianus, Apodemus agrarius and Tscherskia triton. In addition to habitat, Bartonella species infection could be affected by the rodent species as well. Among the Bartonella species detected in this area, B. grahamii was the dominant epidemic species (accounting for 71.43%). B. grahamii exhibited four distinct clusters, and showed a certain host specificity. In addition, 11 haplotypes of B. grahamii were observed using DNASP 6.12.03, among which nine haplotypes were novel. Overall, high occurrence and genetic diversity of Bartonella were observed among small rodents in the Shangdang Basin; this information could potentially help the prevention and control of rodent-Bartonella species in this area. 相似文献
5.
1