Effects and Clinical Significances of Orally Supplementary Soybean β-Conglycinin in Subjects with Dyslipidemia and Renal Dysfunction

Abstract

Chronic kidney disease often accompanies dyslipidemia. Statin is known as the most efficient agent for reducing plasma LDL-C. Fibrate is used in high TG and/or also used in combined hyperlipidemia (high TG and LDL-C). However, combinational use of statin and fibrate for patients with dyslipidemia having renal dysfunction are contraindicated.β-CG, a major component of soy protein, has been reported to decrease serum TG, LDL levels and visceral fat [1][2][3][4]. In addition, β-conglycinin inhibits hepatic fatty acid synthesis, and improves insulin sensitivity [5][6][7]. Accordingly, β-conglycinin may help to improve lipid abnormalities in patients with renal dysfunction as a supplementary food.The present study was performed to evaluate the efficacy of soybean β-conglycinin on hyperlipidemia (serum triglyceride ≥ 1.69 mmol/L and/or serum LDL-cholesterol ≥ 3.62 mmol/L) in subjects with renal dysfunction (Cr ≥ 88.4 μmol/L or eGFR < 60 ml/min/1.73m2) under carefully controlled conditioning of protein intake. In an additional study, the effects of β-CG intake on some subjects without restriction of the 5g protein intake have been observed for another 6 months after the study. Materials and Methods Supplementary foodSoybean β-conglycinin was manufactured by the method developed previously [8], and orally used in the form of candy type supplement. The powder of β-conglycinin consisted of 88% pure β-conglycinin, 5% other soy protein, 2% mineral and 5% water, which were sterilized for food use and spray dried from the defatted soy flowers. A nutritional composition of the supplement was shown in Table 1. The test candy contained 0.575 g of the pure β-conglycinin per piece (Table 1).