Goreisan-mediated suppression of chemokine and cytokine production in astrocytes under AQP4-expressing conditions.

Aim: Aquaporin-4 (AQP4), predominantly expressed in astrocytes, has been implicated in neuroinflammation through the amplification of cytokine and chemokine production. Goreisan (GRS), a traditional Japanese herbal medicine, modulates AQP4-related water homeostasis. However, its effects on AQP4-associated inflammatory processes remain unclear. This study aimed to elucidate the anti-inflammatory effects of GRS, with particular emphasis on inflammatory responses observed under AQP4-expressing conditions. Methods: Results: GRS suppressed LPS- and TNF-α-induced cytokine and chemokine mRNA expression in primary astrocytes and AQP4-expressing NIH-3T3 cells. Conclusion: These findings indicate that the effects of GRS on inflammatory gene expression and ERK activation are associated with AQP4-expressing conditions. However, the present data do not establish AQP4 as a direct or primary molecular target of GRS. Therefore, GRS may provide a potential pharmacological approach for modulating inflammatory responses observed under AQP4-expressing conditions, although further studies are required to confirm its therapeutic relevance.