Dehydrocorydaline inhibits elevated mitochondrial membrane potential in lipopolysaccharide-stimulated macrophages

Activated macrophages play a critical role in the pathogenesis of numerous diseases by producing pro-inflammatory cytokines such as interleukin (IL)-1β and IL-6. While the mechanisms of bacterial component recognition and signal transduction have been well investigated, viability regulation in activated macrophages remains unclear. We screened herbal ingredients to find an agent that reduces the viability of lipopolysaccharide (LPS)-stimulated macrophages and observed that dehydrocorydaline, a component of Corydalis yanhusuo, reduced the viability of macrophage-derived RAW264.7 cells and primary macrophages in the presence of LPS. Dehydrocorydaline inhibited the elevation of mitochondrial membrane potential and induced ATP depletion in LPS-stimulated macrophages but neither affected basal mitochondrial membrane potential nor ATP content in non-stimulated macrophages. Dehydrocorydaline also prevented increased concentrations of IL-1β and IL-6 in culture media of LPS-stimulated macrophages. Mode of dehydrocorydaline action indicates that elevated mitochondrial membrane potential may be a novel target to specifically reduce viability and suppress cytokine production in LPS-stimulated macrophages.

Research highlights► Mitochondrial membrane potential is elevated in LPS-stimulated macrophages. ► Dehydrocorydaline inhibits the elevated mitochondrial membrane potential. ► The inhibitory action reduces viability of the stimulated macrophages. ► The inhibitory action interrupts cytokine production in the stimulated macrophages.