Terpenes are cyclic hydrocarbons constituted by isoprene units. They are distributed in the vegetable kingdom in the form of oxygenated derivatives (alcohols,
aldehydes, carboxyl acids, esters) (36,37). Triterpenic
saponosides are heterosides (formed by a carbohydrate
and a non-glycosid group or aglycone) which can be toxic for animals (38). They alter cell membranes by interacting with their lipid layer and through their anti-ATPase power, thus disturbing sodium transport (39,40).
Glycyrrhizin is a triterpenic saponoside present in
herbal remedies like Syo-Saiko-To, which are associated
with hepatotoxicity. The most characteristic lesions have
been centrilobular necrosis and fibrosis in cases of prolonged consumption (14).
Germander (Teucrium chamaedrys) is a herb whose
active principles are furane-neo-clerodane-diterpenoids.
These are metabolized by CYP3A to reactive metabolites, which covalently bind to proteins and reduce intracellular concentrations of glutathione (GSH). This increases calcium concentration, and transglutaminase is
activated to form aggregates with cytoskeleton proteins.
Increased calcium activates endonucleases, which fragment nuclear DNA and favor apoptosis (41,42)