著者
Tatsuhiro Akaishi Shohei Yamamoto Kazuho Abe
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.45, no.3, pp.301-308, 2022-03-01 (Released:2022-03-01)
参考文献数
45
被引用文献数
7

Neuroinflammation induced by activated microglia is a key feature of neurodegenerative diseases such as Alzheimer’s disease. The natural flavonoid 3′,4′,7-trihydroxyflavone protects nerve cells from oxidative stress-mediated apoptosis and inhibits the aggregation of amyloid β protein in vitro. However, little is known about its effects on microglial activation. In this study, we investigated the effects of 3′,4′,7-trihydroxyflavone on lipopolysaccharide (LPS)- or interferon-γ (IFN-γ)-induced neuroinflammatory responses in MG6 microglial cells. 3′,4′,7-Trihydroxyflavone inhibited LPS- or IFN-γ-mediated nitric oxide (NO) generation and the upregulation of inducible NO synthase (iNOS) in MG6 cells. 3′,4′,7-Trihydroxyflavone also suppressed LPS- or IFN-γ-mediated phosphorylation of signal transducer and activator of transcription 1 (STAT1), which is crucial for iNOS expression. LPS stimulation induced rapid phosphorylation of c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), and extracellular signal-regulated kinase (ERK) in MG6 cells. 3′,4′,7-Trihydroxyflavone significantly inhibited the LPS-mediated phosphorylation of JNK, but not that of ERK and p38 MAPK. The inhibitory effect of 3′,4′,7-trihydroxyflavone on NO generation was mimicked by pharmacological inhibition of the JNK signaling pathway with SP600125. Furthermore, SP600125 significantly inhibited LPS- or IFN-γ-mediated phosphorylation of STAT1 in MG6 cells. These results suggest that 3′,4′,7-trihydroxyflavone exerts anti-neuroinflammatory effects via inhibition of the JNK-STAT1 pathway in microglia.
著者
Shohei Yamamoto Ken Mishina Akihiro Maruta
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE Communications Express (ISSN:21870136)
巻号頁・発行日
vol.8, no.12, pp.507-512, 2019 (Released:2019-12-01)
参考文献数
14
被引用文献数
9

Eigenvalue communication is a promising technology that can overcome capacity limitations caused by the Kerr nonlinearity in optical fibers. In this letter, we propose an artificial neural network-based demodulation method for optical eigenvalue-modulated signals using on-off encoding. The proposed method has a power margin improvement of 9.2 dB at the bit error rate of 3.8 × 10−3 compared with the conventional inverse scattering transform-based demodulation method in numerical simulations.