Arzanol: A Review of Chemical Properties and Biological Activities

Arzanol, a prenylated phloroglucinol–α-pyrone heterodimer from Helichrysum italicum, displays a broad range of pharmacological properties. This review compiles scientific data from the first characterization of the compound in 2007 to present, on its chemistry, conformational behavior, bioactivities, molecular targets, and pharmacokinetics. The conformational flexibility of arzanol, driven by intramolecular hydrogen bonding, enables multitarget interactions. Arzanol shows potent anti-inflammatory activity through NF-κB inhibition and dual suppression of mPGES-1 and 5-LOX, robust antioxidant and cytoprotective effects via radical scavenging and metal chelation, and selective antibacterial activity against drug-resistant Staphylococcus aureus. It also modulates autophagy, mitochondrial function, and metabolic pathways, with high-affinity binding to brain glycogen phosphorylase and SIRT1. Pharmacokinetic data indicate gastrointestinal stability, intestinal absorption, and limited blood–brain barrier penetration. In vivo, arzanol exhibits neuroprotective, neurobehavioral, and metabolic effects, while showing selective cytotoxicity toward cancer cells with minimal impact on normal cells. Its multitarget profile, favorable safety, and oral bioavailability support further development for inflammatory, metabolic, and degenerative disorders.