Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan.
Food and Biodynamic Chemistry Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan.
Front Endocrinol (Lausanne). 2020 Jul 3;11:379. doi: 10.3389/fendo.2020.00379. eCollection 2020.
Excessive intake of fat is a major risk factor for lifestyle-related diseases such as heart disease and also affects brain function such as object recognition memory, social recognition, anxiety behavior, and depression-like behavior. Although oxytocin (OXT) has been reported to improve object recognition, social recognition, anxiety behavior, and depression-like behavior in specific conditions, previous studies did not explore the impact of OXT in high-fat diet (HFD)-fed mice. Furthermore, it remains unclear whether intake of HFD affects OXT/oxytocin receptor (OXTR) in the brain. Here, we demonstrated that peripheral OXT administration improves not only social recognition but also object recognition and depressive-like behavior in HFD-fed mice. In contrast, peripheral OXT administration to HFD-fed male mice increased fear and anxiety-related behavior. In addition, we observed that intake of HFD decreased and mRNA expression in the hippocampus, specifically. Furthermore, peripheral OXT administration increased mRNA expression in the hypothalamus. Altogether, these findings suggest that OXT has the potential to improve various recognition memory processes via peripheral administration but also has side effects that increase fear-related behavior in males.
过量摄入脂肪是导致与生活方式相关疾病（如心脏病）的一个主要危险因素，同时也会影响大脑功能，如物体识别记忆、社交识别、焦虑行为和类似抑郁的行为。虽然已经有报道称催产素（OXT）可以改善特定条件下的物体识别、社交识别、焦虑行为和类似抑郁的行为，但之前的研究并未探讨 OXT 在高脂肪饮食（HFD）喂养的小鼠中的影响。此外，目前尚不清楚 HFD 的摄入是否会影响大脑中的 OXT/催产素受体（OXTR）。在这里，我们证明了外周给予 OXT 不仅可以改善社交识别，还可以改善 HFD 喂养的小鼠的物体识别和类似抑郁的行为。相比之下，外周给予 OXT 会增加 HFD 喂养雄性小鼠的恐惧和焦虑相关行为。此外，我们观察到 HFD 的摄入会降低海马体中的 和 mRNA 表达，特别是 。此外，外周给予 OXT 会增加下丘脑的 mRNA 表达。总的来说，这些发现表明 OXT 通过外周给药有可能改善各种识别记忆过程，但也有增加雄性动物恐惧相关行为的副作用。
