3β-Hydroxy-Δ5-steroidal congeners from a column fraction of Dendronephthya puetteri attenuate LPS-induced inflammatory responses in RAW 264.7 macrophages and zebrafish embryo model

Abstract

Bioactive compounds from marine organisms and their action mechanisms have provided new insights into medicinal and natural product research. Here, we report the identification of 3β-hydroxy-Δ5-steroidal congeners from a purified column fraction (DPCMH24) of the soft coral Dendronephthya puetteri harvested from Jeju, South Korea. DPCMH24 exerted strong anti-inflammatory effects through a dose-dependent decrease in the levels of nitric oxide (NO) in LPS-induced RAW 264.7 macrophages (IC₅₀ value = 6.54 ± 0.38 μg mL⁻¹). Further, DPCMH24 attenuated the levels of PGE₂ and the pro-inflammatory cytokines, TNF-α, IL-1β, and IL-6. The above effects were mediated via the inhibition of nuclear factor κB activation and mitogen-activated protein kinase pathways. In vivo evaluation indicated that DPCMH24 reduced NO, iNOS, COX-2, ROS production and cell death in LPS-induced zebrafish embryos, confirming its anti-inflammatory potential. The constituent compounds were identified by GC-MS/MS analysis. These findings suggest that the steroidal congeners from D. puetteri may offer ample therapeutic potential against LPS-induced inflammation.