Bis(methylthio)gliotoxin is a fungal metabolite originally isolated from G. deliquescens that has diverse biological activities. It inhibits PAF- and collagen-induced platelet aggregation in rabbit platelet-rich plasma (IC50s = 8.4 and 84.2 μM, respectively) but has no effect on arachidonic acid- or ADP-induced platelet aggregation (IC50s = >400 μM). Bis(methylthio)gliotoxin inhibits growth of HCT116 colon cancer cells (IC50 = 23.56 μM). It inhibits PAF-induced bronchoconstriction in guinea pigs when administered at a dose of 0.1 mg/kg and is less toxic to mice (LD50 = >500 mg/kg) than gliotoxin . Bis(methylthio)gliotoxin has been used as a serum biomarker in patients infected with invasive aspergillosis.
This naturally occurring indole derivative (FW = 356.47 g/mol; CAS 74149- 38-5), also known as bis(methylthio)gliotoxin and dimethylgliotoxin, is a platelet-acivating factor (PAF) antagonist that inhibits PAF-induced platelet aggregation. The parent compound, gliotoxin is a dual inhibitor of famesyltransferase and geranylgeranyl-transferase. Bisdethiobis(methylthio)gliotoxin is a minor metabolite of Gliocladium deliquescens, Radiocarbon tracer experiments showed it is formed, apparently irreversibly, from gliotoxin. It has also been synthesized from gliotoxin by reduction and methylation. Bisdethio-bis(methylthio)gliotoxin also binds Cu+ and Ag+ ions.
