Anti-inflammatory effects of 1,7-dihydroxy-3,4-dimethoxyxanthone through inhibition of M1-phenotype macrophages via arginine/mitochondrial axis.

It is known that 1,7-dihydroxy-3,4-dimethoxyxanthone (XAN), derived from Securidaca inappendiculata Hassk., exhibits anti-inflammatory and analgesic activities and inhibits M1 polarization of macrophages. However, its ability to alleviate inflammation induced by pro-inflammatory cytokines in THP-1 cells and its anti-inflammatory mechanisms remain unclear.