Anti-inflammatory polyoxygenated cyclohexene derivatives from Uvaria macclurei

Two undescribed polyoxygenated seco-cyclohexene derivatives named macclureins A and B, and three undescribed polyoxygenated cyclohexene derivatives macclureins C-E, together with 15 known analogues were isolated from the twigs and leaves of Uvaria macclurei. Their structures were established by extensive spectroscopic and circular dichroism analyses. Macclurein C is a chlorinated polyoxygenated cyclohexene. All isolates were evaluated for their anti-inflammatory activities on NO generation in the LPS-stimulated RAW 264.7 cells. (-)-Zeylenone showed the most potent effect against NO production with the IC₅₀ value of 20.18 μM. Meanwhile, (-)-zeylenone also decreased the mRNA expression of pro-inflammatory factors IFN-γ, iNOS, IL-6 and TNF-α via downregulating NF-κB signaling pathway. Further in vivo experiments using a mouse model of sepsis showed that (-)-zeylenone significantly alleviated sepsis severity by measuring weight, murine sepsis score, survival rate and the serum levels of pro-inflammatory factors TNF-α and IL-6.