Imaging Membrane Lipids During Neurodegeneration

细胞的质膜主要由脂质组成，是一种流体动力学结构，具有改变其组成和密度的能力，以调整和反应其外部环境。一种方法是通过形成称为脂筏的专门的膜微区。由于其结构的可变性，成像脂质（和脂筏）已经提出了挑战，特别是当试图通过使用标准成像方法检测它们时。因此，该提案将采用新颖和创新的方法来检测和表征膜脂质的组成，包括存在于脂筏中的那些。 该提案将进一步表征膜脂质组成如何响应于不同的神经毒性刺激而变化，并将改变膜组成与神经元细胞死亡的脆弱性相关联。在这里，我们提出了两种创新的手段，成像成分的神经元膜脂质在体外和体内模型的脑损伤与以下具体目标：（1）检查反应的脂筏结构域后的压力在体外和（2）图像神经节苷脂和其他鞘脂内的脂筏结构域使用成像质谱。这两个目标都是可以实现的，可以在NSERC发现补助金的5年时间框架内完成。 MSI是一种相对较新的成像技术，虽然有几个加拿大直觉使用MALDI-TOF分析样品，很少使用MALDI-TOF成像脂质原位。 我们认为这是NSERC发现补助金的一个明显优势 提议 这项研究计划的影响将超出我们实验室的发现。 我们希望为使用这些成像技术，特别是IMS建立一个强有力的理由，并使其提供给大学社区。 这将提供一个物质来源，使不同的研究小组之间能够产生科学协同作用。 我们认为，这项研究计划的影响也将通过高素质人员的特殊培训潜力来感受。 通过提供独特的培训环境，学员可以学习体外和体内技术，我们将提供坚实的培训和支持基础，帮助他们取得成功。

The plasma membrane of cells, composed mainly of lipids, is a fluid dynamic structure that has the ability to change its composition and density to adjust and react to its external environment. One way to do this is through the formation of specialized membrane micro domains called lipid rafts. Due to their variability of structure, imaging lipids (and lipid rafts) have posed a challenge, especially when trying to detect them by using standard imaging methods. Therefore this proposal will employ novel and innovative methodology to detect and characterize the composition membrane lipids, including those present in lipid rafts. This proposal will further characterize how membrane lipid composition changes in response to different neuro-toxic stimuli and will correlate shifting membrane composition with vulnerability to neuron cell death. Here we propose two innovative means of imaging components of neuronal membrane lipids in vitro and in vivo models of brain injury with the following specific aims: (1) Examine the response of lipid raft domains following stress in vitro and (2) Image gangliosides and other sphingolipids within lipid raft domains using imaging mass spectrometry. Both these aims are achievable and can be completed within the 5 year time-frame of an NSERC Discovery Grant. MSI is a relatively new imaging technique, and although there are several Canadian intuitions using MALDI-TOF analysis of samples, very few are using MALDI-TOF to image lipids in situ. We feel this is a distinct advantage of this NSERC Discovery Grant proposal. The impact of this research program will extend beyond the findings from our laboratory. We hope to build a strong rationale for the use of these imaging techniques, especially with respect to IMS and make them available to the University community. This will provide a physical source where scientific synergy can take place among different research groups. We feel that the impact of this research program will also be felt through the exceptional training potential of highly qualified personnel. By providing a unique training environment where trainees can learn both in vitro and in vivo techniques, we will provide a solid foundation of training and support to help them become successful.