Reduction of the cytotoxicity of triphenyltin chloride using cyclodextrins

This report shows that cyclodextrins increase by up to 40% the survival of a marine nematode exposed to triphenyltin chloride. Environmental contamination by organotins has induced toxic effects such as endocrine disruption and destruction of the membrane structure of aquatic organisms. However, techniques to reduce organotin toxicity are scarce. Here, we tested α-, β-, and γ-cyclodextrins to reduce toxicity induced by triphenyltin chloride. We analyzed a receptor cofactor ligand assay system in vitro, parallel artificial membrane permeability assay, and the survival of Prochromadorella sp. 1, one of the nematodes which is served as biomarkers for ecotoxicological assessment. The passive transport of triphenyltin chloride through the artificial membrane was suppressed about 20 and 40% by α- and γ-cyclodextrins and β-cyclodextrin, respectively. On the other hand, the transcription activity in vitro by triphenyltin chloride using the receptor cofactor ligand assay system was not suppressed by cyclodextrins. These results show that cyclodextrins do not inhibit directly the transcription activity of triphenyltin chloride but does inhibit the incorporation of triphenyltin chloride into the target cell. The survival ratio of Prochromadorella sp. 1 during 24-h exposure to triphenyltin chloride of 5 × 10 ^-6 mol/L was about 5%. The additions of α-, β-, and γ-cyclodextrins increased the survival ratio of about 15, 40, and 20%, respectively. Therefore, cyclodextrins, especially β-cyclodextrin, play an important role in reducing the cytotoxicity by inhibiting the incorporation of triphenyltin chloride into the target cell. Cyclodextrins use in food and pharmaceutical industries can also be applied for the reduction of the toxicities of chemical contaminants.