Erikson Keith M, El-Khouri Kristina, Petric Radmila, Tang Chenhao, Chen Jinlan, Vasquez Delicia Esther Cardenas, Fordahl Steve C, Jia Zhenquan
Department of Nutrition, University of North Carolina, Greensboro, NC 27401, USA.
Department of Biology, University of North Carolina, Greensboro, NC 27401, USA.
Antioxidants (Basel). 2023 May 11;12(5):1081. doi: 10.3390/antiox12051081.
Abnormal cholesterol metabolism can lead to oxidative stress in the brain. Low-density lipoprotein receptor (LDLr) knockout mice are models for studying altered cholesterol metabolism and oxidative stress onset in the brain. Carbon nanodots are a new class of carbon nanomaterials that possess antioxidant properties. The goal of our study was to evaluate the effectiveness of carbon nanodots in preventing brain lipid peroxidation. LDLr knockout mice and wild-type C57BL/6J mice were treated with saline or 2.5 mg/kg bw of carbon nanodots for a 16-week period. Brains were removed and dissected into the cortex, midbrain, and striatum. We measured lipid peroxidation in the mouse brain tissues using the Thiobarbituric Acid Reactive Substances Assay and iron and copper concentrations using Graphite Furnace Atomic Absorption Spectroscopy. We focused on iron and copper due to their association with oxidative stress. Iron concentrations were significantly elevated in the midbrain and striatum of the LDLr knockout mice compared to the C57BL/6J mice, whereas lipid peroxidation was greatest in the midbrain and cortex of the LDLr knockout mice. Treatment with carbon nanodots in the LDLr knockout mice attenuated both the rise in iron and lipid peroxidation, but they had no negative effect in the C57BL/6J mice, indicating the anti-oxidative stress properties of carbon nanodots. We also assessed locomotor and anxiety-like behaviors as functional indicators of lipid peroxidation and found that treatment with carbon nanodots prevented the anxiety-like behaviors displayed by the LDLr knockout mice. Overall, our results show that carbon nanodots are safe and may be an effective nanomaterial for combating the harmful effects caused by lipid peroxidation.
胆固醇代谢异常可导致大脑氧化应激。低密度脂蛋白受体（LDLr）基因敲除小鼠是研究大脑中胆固醇代谢改变和氧化应激发生的模型。碳纳米点是一类具有抗氧化特性的新型碳纳米材料。我们研究的目的是评估碳纳米点预防脑脂质过氧化的有效性。LDLr基因敲除小鼠和野生型C57BL/6J小鼠用生理盐水或2.5mg/kg体重的碳纳米点处理16周。取出大脑并解剖成皮质、中脑和纹状体。我们使用硫代巴比妥酸反应物质分析法测量小鼠脑组织中的脂质过氧化，并使用石墨炉原子吸收光谱法测量铁和铜的浓度。由于铁和铜与氧化应激有关，我们重点研究了它们。与C57BL/6J小鼠相比，LDLr基因敲除小鼠中脑和纹状体中的铁浓度显著升高，而LDLr基因敲除小鼠中脑和皮质中的脂质过氧化最为严重。LDLr基因敲除小鼠用碳纳米点处理可减轻铁的升高和脂质过氧化，但对C57BL/6J小鼠没有负面影响，表明碳纳米点具有抗氧化应激特性。我们还评估了运动和焦虑样行为作为脂质过氧化的功能指标，发现用碳纳米点处理可预防LDLr基因敲除小鼠表现出的焦虑样行为。总体而言，我们的结果表明，碳纳米点是安全的，可能是一种有效的纳米材料，可对抗脂质过氧化造成的有害影响。
