DRUG DEVELOPMENT REPORT .9. PHARMACOLOGY OF GINGER, ZINGIBER-OFFICINALE

In traditional medicine the rhizome Of ginger was held to possess medi cinal properties. The scientific investigations relating to consumptio n of fresh or powdered rhizome by humans, and in vitro effects of aque ous and organic extracts, and of volatile oils are reviewed. Pungent c omponents of ginger inhibit cyclooxygenase and lipoxygenase activity i n the arachidonic acid metabolic pathway and thereby probably reduce i nflammation and relieve pain in rheumatic disorders and migraine heada che. Consumption of ginger reduces plasma thromboxane B2 (TXB2) levels in humans. Ginger is reported to reduce nausea, vertigo and vomiting for which the mechanism of action is, however, not yet understood. Eff ects on the gastrointestinal system include increase in bile secretion and an anti-emetic action. An acetone extract of ginger and (6)-shoga ol given orally, accelerate gastroinstestinal movement in mice, while given i.v., (6)-shogaol inhibits such movement. Galanolactone antagoni ses 5-HT3 receptors which may explain the anti-emetic and gastrointest inal movement enhancing effects. Zingiberone and (6)-gingerol are repo rted to protect against gastric mucosal lesions. (6)-Shogaol is known to reduce blood pressure by both a central and a peripheral action. (8 )-Gingerol has a cardiotonic action via enhancement of the Ca-ATPase i n the sarcoplasmic reticulum. Ginger contains mutagenic (gingerol and shogaol) and anti-mutagenic (zingiberone) compounds. Ginger extract ex hibits cytotoxic effects in cultured plant cells but it is not known w hether ginger can suppress tumour growth in experimental animals or hu mans. Some of the chemical compounds from ginger may prove to have ant i-inflammatory, anti-emetic, cardiotonic and gastroprotective properti es in humans without side effects.