活体内抑郁症相关活性分子的双光子荧光成像研究

Depression is a mood disorder that seriously threats human health. Because of the complicated pathogenic factors and pathogenesis, it’s a major challenge for neuroscience and medicine field to effective prevention and therapy of depression. Therefore, the research on molecular mechanism for occurrence and development of depression has been attracted extensive attention. It is of significant for revealing the mechanism of depression by accurately detecting the bioactive molecules including neurotransmitter, hydrolase/synthetase, metal ions, and uncovering their regulatory effects on neuron. Two-photon fluorescence imaging is one of the effective tools for in vivo study. However, ideal fluorescent probes are still scarce. To solve this issue, this project plans to construct a series of fluorescent probes with rapid response, high stability, excellent biocompatibility to realize the in situ two-photon fluorescence imaging of active molecules in neuron sensitively and selectively. By establishing different models of depressive mice, we intend to systematically investigate the changes of active molecules and explore the related signal pathway, which will provide important information and ideal probes for elucidating the molecular mechanism for occurrence and development of depression.

抑郁症是一类严重威胁人类健康的心境障碍。由于致病因素复杂、病因不清、发病机制不详，对抑郁症的有效预防和治疗一直是神经科学及医学领域的重大挑战。因此，抑郁症发生发展的分子机制研究受到学术界的广泛关注。精准检测神经元内的生物活性分子如神经递质、水解酶/合成酶、金属离子，并探讨它们的种类和浓度变化对神经元功能的调控作用，对揭示抑郁症的发生发展机制至关重要。双光子荧光成像技术是活体分析的最有效手段之一，但目前缺乏理想的探针。针对上述问题，本项目拟基于对生物活性分子的特异性识别反应，利用电子转移或能量转移光信号调控机制，构建一系列应答快速、性质稳定、生物相容性好的荧光探针，实现对活体脑神经元中活性分子的高灵敏度、高选择性原位双光子荧光成像。建立不同的抑郁症小鼠模型，系统研究活性分子的变化规律，深入探讨相关的信号通路，为全面揭示抑郁症发生发展的相关分子机制研究提供重要信息和理想的成像探针。

本项目围绕目前检测活体脑内神经元中抑郁症相关生物活性分子所面临的瓶颈问题，发展了一系列性质稳定、生物相容性良好、应答快速的有机小分子双光子荧光探针，实现了对活体脑内神经元细胞中的活性氧（羟基自由基、超氧阴离子自由基、过氧化氢、臭氧等）、还原性物质（半胱氨酸）、神经递质水解酶（乙酰胆碱酯酶）、金属离子（锌离子等）以及微环境（极性、pH）的高灵敏度、特异性双光子荧光成像分析，系统研究了小鼠活体脑部抑郁症相关生物活性分子的变化，发现了抑郁小鼠脑内氧化还原的失衡、调控神经递质的抑郁症相关蛋白功能紊乱、小鼠脑内微环境的变化，并初步探讨了活性分子参与的相关信号通路，为揭示抑郁症发生发展的相关分子机制研究提供重要信息和理想的成像探针。