Viscotoxin

Viscotoxins are small, cationic, cysteine-rich peptides (thionins) derived from mistletoe (Viscum album) that exhibit cytotoxicity towards various cell types, including tumor cells. They disrupt plasma membrane integrity by binding to and inserting into membranes containing negatively charged phospholipids, resulting in pore formation, increased membrane permeability, and subsequent necrotic cell death. This membranolytic activity is concentration-dependent and can lead to ion channel formation and oxidative stress. While this action underlies their cytotoxic (anticancer and antimicrobial) effects, selectivity for tumor cells is limited, raising concerns about potential toxicity to normal tissues[1][3][5][7].

Other names

Viscotoxinsplant thionins

Direct membrane binding and disruption (pore formation, "carpet" or "toroidal" pore model[1][3][5]); Induction of cell lysis and necrosis via loss of plasma membrane integrity; Possible ion channel formation in anionic membranes