Chemical genetics is a new field of study that employs diverse small-molecule compounds to interrogate specific biological functions. The chemical genetics approach has been recently applied to microglial biology. Microglial cells are the primary immune cells of the brain, and are believed to play a major role in both host defense and tissue repair in the central nervous system. However, excessive microglial activation with overexpression of proinflammatory cytokines and oxidative stress products is linked to the progression of several neurodegenerative diseases. Therefore, suppression of microglial activation and subsequent neuroinflammation may be a potential therapeutic approach against these diseases. From microglia cell-based assays, the natural compound obovatol and several synthetic compounds were identified as inhibitors of microglial activation. They showed strong anti-neuroinflammatory activities in various in vitro and in vivo studies. Nuclear factor-κB and mitogen-activated protein kinase pathways were found to be related to the effects of these compounds on microglia. In particular, based on the affinity purification approach, peroxiredoxin 2 was identified as a microglial target of obovatol. Thus, natural and synthetic compounds are not only important biological tools for the study of microglial physiology and pathology, but they are also attractive candidates for the development of therapeutic drugs against neuroinflammatory and neurodegenerative diseases.
Chemical genetics Microglia Neuroinflammation Neuroprotection Neurodegenerative diseases Obovatol Synthetic compounds
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The authors’ laboratory was supported by the National Research Foundation (NRF) grant funded by the Ministry of Education, Science and Technology (MEST) of Korean government (No. 2009-0078941). This work was also supported by Basic Science Research Program through the NRF funded by the MEST (No. 2010-0029460).
Conflicts of interest
None to declare related to this study.
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