4-O-Methylhonokiol: A lesser-known neolignan from Magnolia species with diverse and promising pharmacological properties

Abstract

This is the first review of 4-O-methylhonokiol (MH) from Magnolia species, a lesser-known neolignan. Contents of the review include an introduction to neolignans, the botany of selected Magnolia species, and the chemistry and plant sources of MH, followed by a brief description of the pharmacokinetics and metabolism of MH in rats. Pharmacological properties of MH include anticancer properties, antidiabetes properties, anti-inflammatory effects, attenuation of memory impairment, anxiolytic or antianxiety effects, antiobesity effects, hair growth promotion, and inhibition of embryo anomalies. Other pharmacological properties of MH include antiseizure, neuroprotective, peroxisome proliferator-activated receptor modulation, inhibition of osteoclastogenesis, protection against liver injury, treatment of cannabis dependence, alleviation of blood–brain barrier dysfunction, cognitive dysfunction amelioration, and cannabinoid receptor inverse agonist. Wherever possible, the properties of MH and its derivatives are compared with those of well-known neolignans such as honokiol and magnolol. Some future research and prospects are suggested.