Tryptanthrin

Tryptanthrin originally isolated from Isatis tinctoria L. has been characterized to have anti-inflammatory activities through the dual inhibition of cyclooxygenase-2 and 5-lipoxygenase mediated prostaglandin and leukotriene syntheses.

Several substances in woad have anti-inflammatory activity. One such substance is tryptanthrin, a known dual inhibitor of cyclooxygenase-2 (COX-2) and 5-LOX. Tryptanthrin is a pharmacologically active compound with potent inhibitory activity on prostaglandin and leukotriene synthesis and on inducible nitric oxide synthase.

Tryptanthrin inhibits MDR1 and reverses doxorubicin resistance in breast cancer cells.
Biochem Biophys Res Commun. 2007 June.  Graduate Institute of Pharmaceutical Sciences, College of Medicine, National Taiwan University, Taipei 10051, Taiwan.
Development of agents to overcome multidrug resistance is important in cancer chemotherapy. Up to date, few chemicals have been reported to down-regulate MDR1 gene expression. We evaluated the effect of tryptanthrin on P-glycoprotein (P-gp)-mediated multidrug resistance in a breast cancer cell line MCF-7. Tryptanthrin depressed overexpression of MDR1 gene. We observed reduction of P-gp protein in parallel with decreases in mRNA in MCF-7/adr cells treated with tryptanthrin. Tryptanthrin suppressed the activity of MDR1 gene promoter. Tryptanthrin also enhanced interaction of the nuclear proteins with the negatively regulatory CAAT region of MDR1 gene promoter in MCF-7/adr. It might result in suppression of MDR1 gene. In addition, tryptanthrin decreased the amount of mutant p53 protein with decreasing mutant p53 protein stability. In conclusion, tryptanthrin exhibited MDR reversing effect by down-regulation of MDR1 gene and might be a new adjuvant agent for chemotherapy.

Tryptophan serotonin home