Ingestion of Fumonisin B1-Containing Culture Material Decreases Cardiac Contractility and Mechanical Efficiency in Swine

Fumonisins are mycotoxins produced primarily by Fusarium verticillioides, a fungus that commonly contaminates corn. Fumonisin ingestion increases plasma and tissue sphingosine and sphinganine concentrations and causes porcine pulmonary edema, which has been attributed to acute left-sided heart failure or increased vascular permeability. We investigated the effect of short-term ingestion of fumonisin B1-containing culture material on cardiac function in pigs. Treated male pigs ( n = 7) received fumonisin-containing culture material which was mixed into the grower diet at 20 mg fumonisin B1/kg body weight each day, while control pigs ( n = 7) were fed only the grower diet on the same schedule as the treated pigs. Pigs were anesthetized after 3 days of receiving either diet and instrumented to accurately characterize the cardiovascular effects of fumonisin ingestion. Fumonisin-treated pigs had lower cardiac outputs and heart rates than control pigs. Fumonisin-treated pigs also had a marked reduction in cardiac contractility, as indicated by decreased values for end-systolic elastance (the gold standard in vivo measure of cardiac contractility), V 0 (the intercept value for the end-systolic pressure–volume relationship), and mechanical efficiency. These data indicate that in pigs, short-term ingestion of fumonisin B1-containing culture material produces negative inotropic and chronotropic effects and decreases mechanical efficiency of the left ventricle. Theses cardiovascular effects are consistent with fumonisin-induced, sphingosine-mediated l -type Ca 2+ channel blockade and suggest that pulmonary edema in pigs fed fumonisin is primarily due to acute left-sided heart failure instead of increased vascular permeability.