August 19/Milan, Italy/Health & Medicine Week -- "Controversial data on the lipid-lowering effect of dietary pea proteins have been provided, and the mechanisms behind this effect are not completely understood. The aim of the study was to evaluate a possible hypolipidemic activity of a pea protein isolate and to determine whether pea proteins could affect the hepatic lipid metabolism through regulation of genes involved in cholesterol and fatty acid homeostasis," researchers in Milan, Italy, report.

"Rats were fed Nath's hypercholesterolemic diets for 28 days, the protein sources being casein or a pea protein isolate from Pisum sativum. After 14 and 28 days of dietary treatment, rats fed pea proteins had markedly lower plasma cholesterol and triglyceride levels than rats fed casein (p<0.05). Pea protein-fed rats displayed higher hepatic mRNA levels of LDL receptor versus those fed casein (p<0.05). Hepatic mRNA concentration of genes involved in fatty acids synthesis, such as fatty acid synthase and stearoyl-CoA desaturase, was lower in pea protein-fed rats than in rats fed casein (p<0.05)," wrote E. Rigamonti and colleagues, University of Milan.

The researchers concluded, "The present study demonstrates a marked cholesterol and triglyceride-lowering activity of pea proteins in rats. Moreover, pea proteins appear to affect cellular lipid homeostasis by upregulating genes involved in hepatic cholesterol uptake and by downregulating fatty acid synthesis genes."

Rigamonti and colleagues published their study in Molecular Nutrition & Food Research ("Hypolipidemic Effect of Dietary Pea Proteins: Impact on Genes Regulating Hepatic Lipid Metabolism." Molecular Nutrition & Food Research, 2010;54(Suppl. 1):S24-S30).

For additional information, contact G. Chiesa, University of Milan, Dept. of Pharmacology Science, Milan, Italy.

From the August 30, 2010, Prepared Foods E-dition