Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 2464 Charlotte Street, HSB-4242, Kansas City, Missouri, 64108, USA.
Department of Neurology and Neurological Sciences, School of Medicine, Stanford University, Stanford, California, 94305, USA.
Pharm Res. 2017 Oct;34(10):2066-2074. doi: 10.1007/s11095-017-2211-6. Epub 2017 Jun 26.
Thiolated-graphene quantum dots (SH-GQDs) were developed and assessed for an efficient preventive means against atherosclerosis and potential toxicity through computational image analysis and animal model studies.
Zebrafish (wild-type, wt) were used for evaluation of toxicity through the assessment of embryonic mortality, malformation and ROS generation. The amounts of SH-GQDs uptaken by mouse macrophage cells (Raw264.7) were analyzed using a flow cytometer. For the time-dependent cellular uptake study, Raw264.7 cells were treated with SH-GQDs (200 μg/ml) at specific time intervals (0.5, 1, 2, 5, 10 and 24 h). The efficacy of SH-GQDs on DiO-oxLDL efflux by Raw264.7 cells was evaluated (DiO, 3,3'-dioctadecyl-oxacarbocyanine) based on the percentage of positive cells containing DiO-oxLDL. TEER of human primary umbilical vein endothelial cells (hUVECs) were examined to assess the barrier function of the cell layers upon being treated with oxLDL.
SH-GQDs significantly enhanced the efflux of oxLDL and down-regulated macrophage scavenger receptor (MSR) in Raw264.7. The ROS levels stimulated by oxidative stress were alleviated by SH-GQDs. oxLDL (10 μg/ml) significantly impaired the barrier function (TEER) of adherence junctions, which was recovered by SH-GQDs (10 μg/ml) (oxLDL: 67.2 ± 2.2 Ω-cm for 24 h; SH-GQDs: 114.6 ± 8.5 Ω-cm for 24 h). The mortality rate (46% for 1 mg/ml) of the zebra fish increased, as the concentrations and exposure duration of SH-GQDs increased. SH-GQDs exerted negligible side effects.
SH-GQDs have target specificity to macrophage scavenger receptor (MSR) and efficiently recovered the ROS levels and TEER. SH-GQDs did not induce endothelial cell layer disruption nor affected zebrafish larvae survival.
硫醇化石墨烯量子点（SH-GQDs）被开发出来，并通过计算图像分析和动物模型研究来评估其作为一种有效的预防动脉粥样硬化和潜在毒性的方法。
利用斑马鱼（野生型，wt）评估毒性，通过胚胎死亡率、畸形和 ROS 生成评估。使用流式细胞仪分析 SH-GQDs 被小鼠巨噬细胞（Raw264.7）摄取的量。为了进行时间依赖性细胞摄取研究，将 Raw264.7 细胞用 SH-GQDs（200μg/ml）在特定时间间隔（0.5、1、2、5、10 和 24h）处理。根据含有 DiO-oxLDL 的阳性细胞的百分比评估 SH-GQDs 对 Raw264.7 细胞 DiO-oxLDL 外排的效果（DiO，3,3'-二辛基氧杂羰花青）。检查人脐静脉内皮细胞（hUVEC）的 TEER，以评估 oxLDL 处理后细胞层的屏障功能。
SH-GQDs 显著增强了 oxLDL 的外排，并下调了 Raw264.7 中的巨噬细胞清道夫受体（MSR）。SH-GQDs 缓解了氧化应激刺激的 ROS 水平。oxLDL（10μg/ml）显著损害了粘附连接的屏障功能（TEER），而 SH-GQDs（10μg/ml）则恢复了该功能（oxLDL：24h 时为 67.2±2.2Ω-cm；SH-GQDs：24h 时为 114.6±8.5Ω-cm）。随着 SH-GQDs 的浓度和暴露时间的增加，斑马鱼的死亡率（1mg/ml 时为 46%）增加。SH-GQDs 几乎没有副作用。
SH-GQDs 对巨噬细胞清道夫受体（MSR）具有靶向特异性，并有效恢复了 ROS 水平和 TEER。SH-GQDs 不会引起内皮细胞层破坏，也不会影响斑马鱼幼虫的存活。
