Tsuji Akihiro, Kotani Eiji, Inoue Yoshihiro H
Biomedical Research Center, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo, Kyoto 606-0962, Japan.
Antioxidants (Basel). 2024 Jun 28;13(7):787. doi: 10.3390/antiox13070787.
Sesame seeds are abundant in sesamin, which exerts health-promoting effects such as extending the lifespan of adult and suppressing oxidative stress by activating the Nrf2 transcription factor. Here, we investigated whether sesamin activated Nrf2 in larval tissues and induced the expression of Nrf2 target genes. In the sesamin-fed larvae, Nrf2 was activated in the central nervous system (CNS), gut, and salivary glands. The ectopic expression of Keap1 in glial cells inhibited sesamin-induced Nrf2 activation in the whole CNS more than in the neurons, indicating that sesamin activates Nrf2 in glia efficiently. We labeled the astrocytes as well as cortex and surface glia with fluorescence to identify the glial cell types in which Nrf2 was activated; we observed their activation in both cell types. These data suggest that sesamin may stimulate the expression of antioxidative genes in glial cells. Among the 17 candidate Nrf2 targets, the mRNA levels of Cyp6a2 and Cyp6g1 in cytochrome P450 were elevated in the CNS, gut, and salivary glands of the sesamin-fed larvae. However, this elevation did not lead to resistance against imidacloprid, which is detoxified by these enzymes. Our results suggest that sesamin may exert similar health-promoting effects on the human CNS and digestive tissues.
芝麻富含芝麻素，芝麻素具有促进健康的作用，比如延长成虫寿命以及通过激活Nrf2转录因子来抑制氧化应激。在此，我们研究了芝麻素是否能在幼虫组织中激活Nrf2并诱导Nrf2靶基因的表达。在喂食了芝麻素的幼虫中，Nrf2在中枢神经系统（CNS）、肠道和唾液腺中被激活。在神经胶质细胞中异位表达Keap1对芝麻素诱导的整个CNS中Nrf2激活的抑制作用，在神经胶质细胞中比在神经元中更明显，这表明芝麻素能有效地在神经胶质细胞中激活Nrf2。我们用荧光标记星形胶质细胞以及皮质和表面神经胶质细胞，以识别激活Nrf2的神经胶质细胞类型；我们观察到这两种细胞类型中Nrf2均被激活。这些数据表明芝麻素可能会刺激神经胶质细胞中抗氧化基因的表达。在17个候选Nrf2靶标中，喂食了芝麻素的幼虫的CNS、肠道和唾液腺中，细胞色素P450中的Cyp6a2和Cyp6g1的mRNA水平升高。然而，这种升高并未导致对由这些酶解毒的吡虫啉产生抗性。我们的结果表明芝麻素可能对人类CNS和消化组织发挥类似的促进健康的作用。
