Cereal fiber improves blood cholesterol profiles and modulates intestinal cholesterol metabolism in C57BL/6 mice fed a high-fat, high-cholesterol diet.

Shufen Han,Xing Tong,Wei Zhang,Chunling Fu,Liqiang Qin,Ru Zhang,Weiguo Zhang,Jun Jiao

doi:10.29219/fnr.v63.1591

Abstract

BackgroundDietary intake of cereal fiber has been reported to benefit lipid metabolism through multiple mechanisms. The present study aimed to discover the potential mechanisms by which cereal fiber could modify the intestinal cholesterol metabolism.DesignMale C57BL/6 mice were fed a reference chow (RC) diet; high-fat, high-cholesterol (HFC) diet; HFC plus oat fiber diet; or HFC plus wheat bran fiber diet for 24 weeks. Serum lipids were measured by enzymatic methods. Western blot was used to determine the protein expressions involved in intestinal cholesterol metabolism.ResultsOur results showed that HFC-induced elevations of serum triglycerides, total cholesterol, and low-density lipoprotein cholesterol were normalized in both groups that received cereal fiber. At the protein level, compared with the HFC diet group, the two cereal fibers, especially the oat fiber, significantly increased the protein expression of peroxisome proliferator-activated receptor alpha, liver X receptor alpha, sterol regulatory element-binding protein (SREBP) 2, low-density lipoprotein receptor, adenosine triphosphate (ATP)-binding cassette A1, and ATP-binding cassette G1, while decreasing the protein expression of Niemann-Pick C1-like protein 1, SREBP-1, fatty acid synthase, and acetyl-coenzyme A carboxylase, which were involved in intestinal cholesterol metabolism.ConclusionTaken together, increased intake of cereal fiber improved blood cholesterol profiles and increased the intestinal cholesterol efflux and cholesterol clearance in C57BL/6 mice fed a HFC diet. Oat fiber had a stronger effect than wheat bran fiber on cholesterol metabolism by modulating the PPARα, LXRα, and SREBP signaling pathways.

Highlights

Dietary intake of cereal fiber has been reported to benefit lipid metabolism through multiple mechanisms
At the protein level, compared with the HFC diet group, the two cereal fibers, especially the oat fiber, significantly increased the protein expression of peroxisome proliferator-activated receptor alpha, liver X receptor alpha, sterol regulatory element-binding protein (SREBP) 2, low-density lipoprotein receptor, adenosine triphosphate (ATP)-binding cassette A1, and ATP-binding cassette G1, while decreasing the protein expression of Niemann-Pick C1-like protein 1, sterol regulatory element-binding protein 1 (SREBP-1), fatty acid synthase, and acetyl-coenzyme A carboxylase, which were involved in intestinal cholesterol metabolism
In this study, we explored the role of cereal fiber on blood cholesterol profiles and intestinal cholesterol metabolism in mice fed a high-fat, high-cholesterol diet

Summary

Introduction

Dietary intake of cereal fiber has been reported to benefit lipid metabolism through multiple mechanisms. Design: Male C57BL/6 mice were fed a reference chow (RC) diet; high-fat, high-cholesterol (HFC) diet; HFC plus oat fiber diet; or HFC plus wheat bran fiber diet for 24 weeks. At the protein level, compared with the HFC diet group, the two cereal fibers, especially the oat fiber, significantly increased the protein expression of peroxisome proliferator-activated receptor alpha, liver X receptor alpha, sterol regulatory element-binding protein (SREBP) 2, low-density lipoprotein receptor, adenosine triphosphate (ATP)-binding cassette A1, and ATP-binding cassette G1, while decreasing the protein expression of Niemann-Pick C1-like protein 1, SREBP-1, fatty acid synthase, and acetyl-coenzyme A carboxylase, which were involved in intestinal cholesterol metabolism. Oat fiber had a stronger effect than wheat bran fiber on cholesterol metabolism by modulating the PPARα, LXRα, and SREBP signaling pathways

Methods

Results

Conclusion