Cowpea protein reduces LDL-cholesterol and apolipoprotein B concentrations, but does not improve biomarkers of inflammation or endothelial dysfunction in adults with moderate hypercholesterolemia.

Abstract

The risks of cardiovascular diseases, the leading cause of death in the world, can be reduced by diet. Cowpea protein has been shown to significantly reduce total cholesterol, LDL-cholesterol, and liver steatosis in hamsters. The objective of this proof-of-concept study was to verify whether the consumption of cowpea protein improves lipid profile and biomarkers of inflammation and endothelial dysfunction in adults with moderate hypercholesterolemia. In a randomized, double-blind, crossover design, 38 hypercholesterolemic subjects (LDL-cholesterol = 182.5 ± 2.7 mg/dL) consumed 25 g/day of cowpea protein isolate or 25 g/day of casein (control group) for 6 weeks each, separated by a 4-week washout interval. Fasting blood samples were collected at baseline and at the end of each diet period. Lipids (total cholesterol, LDL-cholesterol, triglycerides, HDL-cholesterol) were determined by enzymatic methods, apolipoproteins (apoA-I and apoB) by standardized immunoassays, inflammatory biomarkers (C-reactive protein) by turbidimetry, and biomarkers of endothelial dysfunction (intercellular adhesion molecule 1 and vascular cell adhesion molecule 1) by enzyme-linked immunosorbent assays. Consumption of cowpea protein significantly reduced total cholesterol ( 12 %), LDL cholesterol ( 18.9 %), non HDL-cholesterol ( 16 %) and apoB ( 14 %), and increased HDL cholesterol (+2.7 %). No significant differences between treatment groups were observed for any of the serum inflammatory or endothelial dysfunction biomarkers. The present findings demonstrated the favorable effect of cowpea protein consumption on proatherogenic serum lipids and apoB in subjects with moderate hypercholesterolemia, similar to what was observed in a previous studies on animals.