Brown Josephine, Villalona Yislain, Weimer Jamie, Ludwig Clare Pickering, Hays Breann T, Massie Lisa, Marczinski Cecile A, Curran Christine Perdan
Department of Biological Sciences, Northern Kentucky University, 100 Nunn Drive, Highland Heights 41099, KY, USA.
Department of Psychological Science, Northern Kentucky University, 100 Nunn Drive, Highland Heights 41099, KY, USA.
Neurotoxicol Teratol. 2020 May-Jun;79:106883. doi: 10.1016/j.ntt.2020.106883. Epub 2020 Apr 11.
The mammalian brain goes through final maturation during late adolescence and early adulthood with sex differences in timing. The key cellular processes, including changes in neurotransmitter receptor density and synaptic pruning, make this age uniquely vulnerable to neurotoxic insults. Teenagers and young adults are the major consumers of energy drinks, which contain high levels of taurine and caffeine. Taurine is one of the most abundant amino acids in the central nervous system, but the effects of supplemental taurine consumption during adolescence has not been well studied. We conducted an initial short-term exposure study with 0.12% taurine in drinking water and a long-term exposure dose-response study using 0.06 and 0.12% taurine in male and female C57BL/6J mice. We examined a broad range of cognitive functions and behaviors and measured neurotransmitter levels. We found no significant differences in anxiety, open field locomotor activity, or sensorimotor gating. However, we found impairments in novel object recognition and sex differences in Morris water maze. When taurine treatment stopped before behavioral experiments began, male mice had significant impairments in spatial learning and memory. In the dose-response study when taurine treatment continued throughout behavioral experiments, females had significant impairments. We also found sex differences in neurotransmitter levels with females having higher levels of glutamate, DOPAC and 5-HIAA. We conclude that both females and males are at risk from excess taurine consumption during final brain maturation.
哺乳动物的大脑在青春期后期和成年早期经历最终成熟,且在时间上存在性别差异。关键的细胞过程,包括神经递质受体密度的变化和突触修剪,使得这个年龄段特别容易受到神经毒性损伤。青少年和年轻人是能量饮料的主要消费者,能量饮料含有高浓度的牛磺酸和咖啡因。牛磺酸是中枢神经系统中含量最丰富的氨基酸之一,但青春期补充牛磺酸的影响尚未得到充分研究。我们对雄性和雌性C57BL/6J小鼠进行了一项初步短期暴露研究,饮用水中添加0.12%的牛磺酸,并进行了一项长期暴露剂量反应研究,使用0.06%和0.12%的牛磺酸。我们检查了广泛的认知功能和行为,并测量了神经递质水平。我们发现焦虑、旷场运动活动或感觉运动门控方面没有显著差异。然而,我们发现新物体识别存在损伤,且在莫里斯水迷宫中有性别差异。当在行为实验开始前停止牛磺酸治疗时,雄性小鼠在空间学习和记忆方面有显著损伤。在剂量反应研究中,当在整个行为实验过程中持续进行牛磺酸治疗时,雌性小鼠有显著损伤。我们还发现神经递质水平存在性别差异,雌性小鼠的谷氨酸、二羟基苯乙酸和5-羟吲哚乙酸水平较高。我们得出结论,在大脑最终成熟过程中,过量摄入牛磺酸对雌性和雄性都有风险。