Preclinical pharmacology studies of zingerone with special reference to potential therapeutic applications

Zingiber officinale Roscoe (ginger) is traditionally used as a culinary spice worldwide. In folklore medicine, raw and fresh ginger has been used for treating nausea and vomiting, to improve liver function and digestion, antidiarrheal, to treat menstrual cramps, and as an aphrodisiac. Zingerone [4-(4-hydroxy-3-methoxyphenyl)-2-butanone] is the major bioactive ingredient present in ginger. Zingerone has shown a wide-range of pharmacological activities in vitro and in vivo studies. While zingerone is present in small amount in fresh ginger, but its level is increased during drying or heating during cooking. The amount of zingerone increases significantly due to the conversion of gingerol into zingerone through retro-aldol reaction. Owing to its strong antioxidant and anti-inflammatory properties, zingerone has the ability to scavenge reactive oxygen species and to assist in curing a wide array of non-communicable diseases associated with oxidative stress such as diabetes mellitus, obesity, cardiometabolic and cardiovascular disorders, neurological abnormalities, osteoarthritic, and certain cancer types. For this review, extensive literature searches were performed using PubMed, Google Scholar, Science Direct, and other search engines. The major aims of our review are to describe the chemical characteristics of zingerone as well as the various in vitro and in vivo studies reported regarding the pharmacological effects of zingerone and the mechanism of action observed at the cellular and molecular levels. The results of published preclinical and few clinical studies suggest that zingerone has several promising therapeutic applications due to its strong antioxidant, anti-inflammatory and anti-proliferative activities without any serious side effects. However, well-designed, randomized, placebo-controlled, and multi-center clinical studies are needed to determine the optimal therapeutic doses, and long-term safety of zingerone.