已经证明,糖尿病会导致大脑中的神经突变性和认知障碍,神经血管相互作用对于维持大脑功能至关重要。然而,血管内皮细胞在糖尿病脑神经突生长和突触形成中的作用尚不清楚。因此,本研究使用BMEC与神经元共培养模型研究了脑微血管内皮细胞(BMEC)对高糖(HG)诱导的神经营养不良的影响。多重免疫荧光标记和蛋白质印迹分析用于检测神经突生长和突触形成,活细胞成像用于检测神经元葡萄糖转运蛋白的摄取功能。我们发现与BMECs共培养可显着降低HG诱导的神经突生长抑制(包括长度和分支形成),并延迟突触前和突触后发育,以及神经元葡萄糖摄取能力的降低,通过用血管内皮生长因子(VEGF)受体拮抗剂SU1498预处理可以预防。为了分析可能的机制,我们收集BMECs培养条件培养基(B-CM)在HG培养条件下处理神经元。结果显示B-CM对HG处理的神经元表现出与BMEC相同的作用。此外,我们观察到VEGF给药可以改善HG诱导的神经元形态畸变。放在一起,目前的结果表明,脑微血管内皮细胞通过激活VEGF受体和内皮VEGF释放,保护高血糖诱导的神经营养不良,并恢复神经元葡萄糖摄取能力.这一结果有助于我们了解神经血管偶联在糖尿病脑发病机制中的重要作用,为研究糖尿病性痴呆的治疗或预防提供了新的策略。高血糖引起神经元葡萄糖摄取的抑制,并损害了神经炎的生长和突触发生。与BMECs/B-CM和VEGF治疗共同保护HG诱导的葡萄糖摄取抑制和神经炎生长和突触形成,它被VEGF受体的阻断所拮抗。葡萄糖摄取的减少可能进一步恶化神经突生长和突触发生的损害。
It has been demonstrated that diabetes cause neurite degeneration in the brain and cognitive impairment and neurovascular interactions are crucial for maintaining brain function. However, the role of vascular endothelial cells in neurite outgrowth and synaptic formation in diabetic brain is still unclear. Therefore, present study investigated effects of brain microvascular endothelial cells (BMECs) on high glucose (HG)-induced neuritic dystrophy using a coculture model of BMECs with neurons. Multiple immunofluorescence labelling and western blot analysis were used to detect neurite outgrowth and synapsis formation, and living cell imaging was used to detect uptake function of neuronal glucose transporters. We found cocultured with BMECs significantly reduced HG-induced inhibition of neurites outgrowth (including length and branch formation) and delayed presynaptic and postsynaptic development, as well as reduction of neuronal glucose uptake capacity, which was prevented by pre-treatment with SU1498, a vascular endothelial growth factor (VEGF) receptor antagonist. To analyse the possible mechanism, we collected BMECs cultured condition medium (B-CM) to treat the neurons under HG culture condition. The results showed that B-CM showed the same effects as BMEC on HG-treated neurons. Furthermore, we observed VEGF administration could ameliorate HG-induced neuronal morphology aberrations. Putting together, present results suggest that cerebral microvascular endothelial cells protect against hyperglycaemia-induced neuritic dystrophy and restorate neuronal glucose uptake capacity by activation of VEGF receptors and endothelial VEGF release. This result help us to understand important roles of neurovascular coupling in pathogenesis of diabetic brain, providing a new strategy to study therapy or prevention for diabetic dementia. Hyperglycaemia induced inhibition of neuronal glucose uptake and impaired to neuritic outgrowth and synaptogenesis. Cocultured with BMECs/B-CM and VEGF treatment protected HG-induced inhibition of glucose uptake and neuritic outgrowth and synaptogenesis, which was antagonized by blockade of VEGF receptors. Reduction of glucose uptake may further deteriorate impairment of neurites outgrowth and synaptogenesis.