Original articles
ZHU Wei, WU Haowei, FU Wenliang, ZHANG Chao, JIN Peng, XING Weiwei, XU Donggang
Objective To study the influence of rosemary essential oil inhalation on the memory of mice experiencing sleep deprivation and to delineate the possible mechanisms involved. Methods C57BL/6J mice were randomly divided into four experimental groups in this study： a control group （Con）, a control group with rosemary essential oil inhalation （Con+REO）, a sleep deprivation group （SD） and a sleep deprivation group with rosemary essential oil inhalation （SD+REO）. A 72-hour sleep deprivation model was induced using the multiple platform water environment method, with the Con+REO and SD+REO groups exposed to rosemary essential oil inhalation. Cognitive function was evaluated through Y-maze and novel object recognition tests. The hippocampal tissue was analyzed for superoxide dismutase （SOD） activity and the concentrations of malondialdehyde （MDA） and glutathione （GSH）. ELISA was used to determine the levels of norepinephrine （NE）, dopamine （DA）, and serotonin 5-hydroxytryptamine（5-HT） in the hippocampus. The expression levels of postsynaptic density 95 （PSD95） and brain-derived neurotrophic factor （BDNF） in the hippocampus were determined using immunoblotting techniques. Results Compared with the Con and Con+REO groups, the SD group demonstrated a significant reduction in the spontaneous alternation percentage in the Y-maze as well as the novel object recognition index. Additionally, there was a pronounced decrease in hippocampal SOD activity and GSH content, a substantial elevation in MDA levels, and a decrease in the levels of DA, NE, and 5-HT. The expressions of PSD95 and BDNF proteins also decreased. In comparison with the SD group, the SD+REO group exhibited a significant increase in the spontaneous alternation percentage in the Y-maze and the novel object recognition index. There was also a marked increase in hippocampal SOD activity and GSH content, a reduction in MDA levels and elevated levels of NE and DA. Moreover, the expressions of PSD95 and BDNF proteins were upregulated. Results The inhalation of rosemary essential oil enhances the memory of sleep-deprived mice, and the underlying mechanism may involve the mitigation of oxidative stress within the hippocampal tissue, the modulation of neurotransmitter levels, and the facilitation of synaptic plasticity.
