Pharmacological studies on tiadenol in type IV patients. Evidence for a mechanism of action different from other lipid-lowering drugs

Tiadenol [bis(hydrosyethylthio) 1–10 decane], a new absorbable hypolipidemic agent differing in chemical structure from clofibrate and related compounds, was tested in hypertriglyceridemic patients, both responsive and non-responsive to dietary treatment. Tiadenol administration was remarkably effective in inhibiting fructose induced hypertriglyceridemia in diet responsive type IV patients; it was ineffective in patients with stable, diet refractory, hypertriglyceridemia. The significant reduction of plasma triglycerides (−42%) in sensitive patients, was not accompanied in this study, by the activation of plasma lipoprotein and hepatic lipases. In a second, longer term investigation of stable type IV patients, tiadenol administration resulted in significant triglyceride decreases in the very low density lipoproteins (VLDL) (−45%), as well as in the low and high density lipoproteins (LDL and HDL) (both −250). The cholesterol content of LDL and HDL was not modified. In VLDL a significant reduction of apoprotein E was observed (from 15.2 ± 4.9 to 11.9 ± 5.9% of VLDL proteins). The reported observations are consistent with a difference in the mode of action of tiadenol from that of other lipid lowering agents, particularly of the clofibrate type.