A study of the chemical binding of allyl isothiocyanate with thyroxine and of the effect of allyl isothiocyanate on lipid metabolism in the rat

Abstract

Two experiments were conducted with allyl isothiocyanate (AITC): one in vitro, to investigate the chemical binding of AITC with thyroxine (T4), tyrosine (Tyr), and leucine (Leu), and the other in vivo, to evaluate the effect of AITC on the blood clotting mechanism and on the protein and lipid contents of rat liver. The in vitro study, which used the techniques of ultraviolet spectroscopy and thin-layer chromatography, indicated the formation of a complex of AITC with T4 and Tyr but not with Leu. The presence of a phenyl ring with an OH group at the position para to the alanine side chain is suggested as a prerequisite for the chemical binding of AITC with amino acids. The in vivo experiment involved administration of AITC, T4, or the ALTC–T4 complex by the intraperitoneal route to young male Sprague–Dawley rats for 30 days. AITC exhibited a strong coagulant effect, which was seemingly mediated by the relatively high plasma phospholipid concentration. T4 and the AITC–T4 complex were without a significant effect on blood coagulation. AITC was without effect on liver protein but increased cholesterol, phospholipid, and total lipid contents markedly. The effect of T4 on the liver protein and lipids was not significant. The AITC-T4 complex caused a significant increase in the liver protein and an intermediate rise in the lipids compared with AITC. The increase in plasma and liver lipid concentrations caused by AITC was probably related to increased hepatic lipid production and decreased clearance of the circulating lipids.