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1.
目的:利用斑马鱼模型研究不同来源和不同类型的磷脂对血管生成的促进作用及其活性差异。方法:将受精后发育24 h和72 h的斑马鱼胚胎脱膜,分别用于评估各磷脂样品(分别以大豆、蛋黄和南美白对虾虾头制备)对斑马鱼体节间血管(intersegmental vessel,ISV)和肠下静脉(subintestinal vein vessel,SIV)生长情况的影响,设置空白对照组、模型组(0.25 μg/mL PTK787)、阳性对照组和磷脂样品组(20、40、80 mg/mL),给药24 h后用荧光显微镜观察并记录各实验组转基因斑马鱼ISV和SIV的生长情况。结果:对于ISV受损斑马鱼而言,3 种磷脂提取物以及2 种磷脂市售产品(药品和保健品)均表现出明显的血管生成促进作用,对于SIV而言,3 种磷脂提取物以及4 种磷脂市售产品(药品和保健品)均表现出明显的血管生成促进作用,相对而言,南美白对虾虾头磷脂促进血管生成活性更强,效果更加明显;5 种磷脂标准品表现出不同程度的血管生成促进作用,对于ISV受损斑马鱼而言,磷脂酰乙醇胺、磷脂酰胆碱、磷脂酰丝氨酸以及高质量浓度(80 mg/mL)的鞘磷脂表现出明显的促血管生成作用,对于SIV受损斑马鱼而言,所有的磷脂标准品均表现出较明显的血管生成促进作用。结论:不同质量浓度的磷脂提取物、市售产品以及磷脂标准品对斑马鱼均具有一定的促血管生成活性。  相似文献   
2.
MicroRNAs (miRNAs) have crucial functions in many cellular processes, such as differentiation, proliferation and apoptosis; aberrant expression of miRNAs has been linked to human diseases, including cancer. Tools that allow specific and efficient knockdown of miRNAs would be of immense importance for exploring miRNA function. Zebrafish serves as an excellent vertebrate model system to understand the functions of miRNAs involved in a variety of biological processes. We designed and employed a strategy based on locked nucleic acid enzymes (LNAzymes) for in vivo knockdown of miRNA in zebrafish embryos. We demonstrate that LNAzyme can efficiently knockdown miRNAs with minimal toxicity to the zebrafish embryos.  相似文献   
3.
研究了羊栖菜多糖(Sargassum fusiforme polysaccharide, SFPS)及辅助超声降解对模式生物斑马鱼幼鱼和成鱼的降血脂作用。将斑马鱼幼鱼分为对照组、高脂组、200 mg/L超声降解羊栖菜多糖组(200-SFPSUD) 、600 mg/L SFPSUD组(600-SFPSUD) 和600 mg/L SFPS组(600-SFPS),实验周期为24 h。斑马鱼成鱼分为对照组、高脂组、30 mg羊栖菜粉组(SFP)、20 mg/L SFPSUD组(20-SFPSUD)、50 mg/L SFPSUD组(50-SFPSUD)和50 mg/L SFPS组(50-SFPS),实验周期为28 d。在斑马鱼幼鱼实验中,600-SFPS组斑马鱼较高脂组血管和腹部脂肪积累较少,600-SFPSUD组斑马鱼体内的脂肪积累更少。斑马鱼成鱼实验中,较高脂组,50-SFPS组斑马鱼肥满度变化率降低25.53%,肝脂酶(HL)、总脂酶(TL)活性分别提高153.00%、123.48%;50-SFPSUD组斑马鱼肥满度变化率降低27.18%,HL、TL活性分别提高168.20%、137.73%。通过苏木精-伊红染色(HE)观察到50-SFPS组和50-SFPSUD组斑马鱼肝脏内脂肪堆积均得到有效抑制,其中SFPSUD的干预效果更为显著。结果表明,SFPS具有降血脂功能,超声降解处理能够提高其降血脂能力,其机制可能是提高了斑马鱼HL和TL活性,从而加速体内脂质代谢速率。该研究可为SFPS、超声降解功能性食品的进一步开发提供理论参考,为人类高脂血症和养殖鱼类肥胖等问题提供新的解决思路。  相似文献   
4.
    
Visualization of Hg(II) and MeHg in their native contexts is significant for examining mercury poisoning, while it is challenging because of indistinguishable fluorescent (FL) signals during FL imaging. Herein, visualizations of mercury methylation and dynamic transformations of Hg(II) and MeHg are achieved in living biological systems. Well distinguishable FL responses (blue emission for Hg(II), yellow emission for MeHg) are obtained by a double‐response FL probe (DPAHB) without any interference. As demonstrated by experimental and computational studies, the distinguishable signals are attributed to selective binding with DPAHB and different inhibition of excited‐state proton transfer. Through control tests for live‐dead markers, mercury methylation is demonstrated to be employed in living biological systems. Therefore, the methylation and dynamic transformations of both ions are monitored in zebrafish by imaging, and these results are confirmed by traditional high‐performance liquid chromatography‐based methods. The methylation of Hg(II) to MeHg, dynamic transformations and final accumulations of both species in zebrafish tissues are visualized successfully. This method is also convenient for fast evaluation of detoxification reagents. This is the first visualization of in vivo mercury methylation and dynamic transformation of both species and is effective for studying pathological processes in their native contexts.  相似文献   
5.
    
The zebrafish embryo is a vertebrate well suited for visualizing nanoparticles at high resolution in live animals. Its optical transparency and genetic versatility allow noninvasive, real‐time observations of vascular flow of nanoparticles and their interactions with cells throughout the body. As a consequence, this system enables the acquisition of quantitative data that are difficult to obtain in rodents. Until now, a few studies using the zebrafish model have only described semiquantitative results on key nanoparticle parameters. Here, a MACRO dedicated to automated quantitative methods is described for analyzing important parameters of nanoparticle behavior, such as circulation time and interactions with key target cells, macrophages, and endothelial cells. Direct comparison of four nanoparticle (NP) formulations in zebrafish embryos and mice reveals that data obtained in zebrafish can be used to predict NPs' behavior in the mouse model. NPs having long or short blood circulation in rodents behave similarly in the zebrafish embryo, with low circulation times being a consequence of NP uptake into macrophages or endothelial cells. It is proposed that the zebrafish embryo has the potential to become an important intermediate screening system for nanoparticle research to bridge the gap between cell culture studies and preclinical rodent models such as the mouse.  相似文献   
6.
    
Aluminium (Al) is the most common natural metallic element in the Earth’s crust. It is released into the environment through natural processes and human activities and accumulates in aquatic environments. This review compiles scientific data on the neurotoxicity of aluminium contamination on the nervous system of aquatic organisms. More precisely, it helps identify biomarkers of aluminium exposure for aquatic environment biomonitoring in freshwater aquatic vertebrates. Al is neurotoxic and accumulates in the nervous system of aquatic vertebrates, which is why it could be responsible for oxidative stress. In addition, it activates and inhibits antioxidant enzymes and leads to changes in acetylcholinesterase activity, neurotransmitter levels, and in the expression of several neural genes and nerve cell components. It also causes histological changes in nerve tissue, modifications of organism behaviour, and cognitive deficit. However, impacts of aluminium exposure on the early stages of aquatic vertebrate development are poorly described. Lastly, this review also poses the question of how accurate aquatic vertebrates (fishes and amphibians) could be used as model organisms to complement biological data relating to the developmental aspect. This “challenge” is very relevant since freshwater pollution with heavy metals has increased in the last few decades.  相似文献   
7.
    
Catechol is a ubiquitous chemical used in the manufacturing of fragrances, pharmaceuticals and flavorants. Environmental exposure occurs in a variety of ways through industrial processes, during pyrolysis and in effluent, yet despite its prevalence, there is limited information regarding its toxicity. While the genotoxicity and gastric carcinogenicity of catechol have been described in depth, toxicological studies have potentially overlooked a number of other effects relevant to humans. Here, we have made use of a general and behavioral larval zebrafish toxicity assay to describe previously unknown catechol-based toxicological phenomena. Behavioral testing revealed catechol-induced hypoactivity at concentrations an order of magnitude lower than observable endpoints. Catechol exposure also resulted in punctate melanocytes with concomitant decreases in the expression of pigment production and regulation markers mitfa, mc1r and tyr. Because catechol is converted into a number of toxic metabolites by tyrosinase, an enzyme found almost exclusively in melanocytes, an evaluation of the effects of catechol on these cells is critical to evaluating the safety of this chemical. This work provides insights into the toxic nature of catechol and highlights the benefits of the zebrafish larval testing platform in being able to dissect multiple aspects of toxicity with one model.  相似文献   
8.
    
Telomere shortening is the main molecular mechanism of aging, but not the only one. The adaptive immune system also ages, and older organisms tend to develop a chronic pro-inflammatory status with low-grade inflammation characterized by chronic activation of the innate immune system, called inflammaging. One of the main stimuli that fuels inflammaging is a high nutrient intake, triggering a metabolic inflammation process called metainflammation. In this study, we report the anti-inflammatory activity of several senolytic drugs in the context of chronic inflammation, by using two different zebrafish models: (i) a chronic skin inflammation model with a hypomorphic mutation in spint1a, the gene encoding the serine protease inhibitor, kunitz-type, 1a (also known as hai1a) and (ii) a non-alcoholic fatty liver disease/non-alcoholic steatohepatitis (NAFLD/NASH) model with inflammation induced by a high-fat diet. Our results show that, although these models do not manifest premature aging, the senolytic drugs dasatinib, navitoclax, and venetoclax have an anti-inflammatory effect that results in the amelioration of chronic inflammation.  相似文献   
9.
    
In aquatic organisms, cadmium exposure occurs from ovum to death and the route of absorption is particularly wide, being represented by skin, gills and gastrointestinal tract, through which contaminated water and/or preys are ingested. It is known that cadmium interferes with the gut; however, less information is available on cadmium effects on an important component of the gut, namely goblet cells, specialized in mucus synthesis. In the present work, we studied the effects of two sublethal cadmium concentrations on the gut mucosa of Danio rerio. Particular attention was paid to changes in the distribution of glycan residues, and in metallothionein expression in intestinal cells. The results show that cadmium interferes with gut mucosa and goblet cells features. The effects are dose- and site-dependent, the anterior gut being more markedly affected than the midgut. Cadmium modifies the presence and/or distribution of glycans in the brush border and cytoplasm of enterocytes and in the goblet cells’ cytoplasm and alters the metallothionein expression and localization. The results suggest a significant interference of cadmium with mucosal efficiency, representing a health risk for the organism in direct contact with contamination and indirectly for the trophic chain.  相似文献   
10.
    
The brain-derived neurotrophic factor (BDNF) was discovered in the last century, and identified as a member of the neurotrophin family. BDNF shares approximately 50% of its amino acid with other neurotrophins such as NGF, NT-3 and NT-4/5, and its linear amino acid sequences in zebrafish (Danio rerio) and human are 91% identical. BDNF functions can be mediated by two categories of receptors: p75NTR and Trk. Intriguingly, BDNF receptors were highly conserved in the process of evolution, as were the other NTs’ receptors. In this review, we update current knowledge about the distribution and functions of the BDNF-TrkB system in the sensory organs of zebrafish. In fish, particularly in zebrafish, the distribution and functions of BDNF and TrkB in the brain have been widely studied. Both components of the system, associated or segregated, are also present outside the central nervous system, especially in sensory organs including the inner ear, lateral line system, retina, taste buds and olfactory epithelium.  相似文献   
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