An in vitro assay system for antihyperlipidemic agents by evaluating lipoprotein profiles from human intestinal epithelium-like cells.

Junichiro Takahashi,Keishi Hata,Yuko Naya,Fumiko Kimura,Yuka Iwama,Yukie Matsumoto,Kikumi Ogihara,Mizuho Itoh,Gen Toshima

doi:10.1007/s13205-012-0085-1

Abstract

We developed an in vitro screening system for antihyperlipidemic activity by measuring lipoprotein profiles secreted from human intestinal epithelium-like cells from the colon cancer cell line, Caco-2. Sodium (Na) butyrate at 5 mM differentiated Caco-2 cells into intestinal epithelium-like cells and numerous microvilli on the apical side of cells were observed under transmission electron microscopy. Real-time RT-PCR analysis revealed that Na butyrate stimulated expression levels of intestinal differentiation markers in Caco-2 cells in a dose-dependent manner and 5 mM Na butyrate up-regulated intestinal alkaline phosphatase, sucrase–isomaltase complex, and microsomal triglyceride transfer protein by 8.1-, 1.9-, and 2.1-fold that of non-treated cells, respectively. Lipoprotein secretions from differentiated Caco-2 cells were promoted by lysophosphatidyl choline and Na oleate, which are a stimulator of lipoprotein secretion and a substrate of triglycerides, respectively. We examined the effects of Pluronic L-81, a lipoprotein secretion inhibitor, on lipoprotein profiles of differentiated Caco-2 cells. Pluronic L-81 at 1.0 μg/ml inhibited TG contents in lipoprotein fractions from cells by 25.6 % and secretion was completely suppressed by the agent at 10 μg/ml.Electronic supplementary materialThe online version of this article (doi:10.1007/s13205-012-0085-1) contains supplementary material, which is available to authorized users.

Highlights

Excessive intakes of dietary sugars and lipids such as triglycerides (TG) and cholesterol cause visceral fat accumulation leading to metabolic syndrome, which includes glucose intolerance, hypertension, dyslipidemia, and obesity
We developed an in vitro screening system for antihyperlipidemic activity by measuring lipoprotein profiles secreted from human intestinal epithelium-like cells from the colon cancer cell line, Caco-2
After dietary TG is cleaved into fatty acids and 2-mono-glycerides by gastric and pancreatic lipase, free fatty acids are incorporated into micelles with cholesterol, bile acids, and phosphatidylcholine (PC), which are absorbed into intestinal epithelium cells

Summary

Introduction

Excessive intakes of dietary sugars and lipids such as triglycerides (TG) and cholesterol cause visceral fat accumulation leading to metabolic syndrome, which includes glucose intolerance, hypertension, dyslipidemia, and obesity. Abstract We developed an in vitro screening system for antihyperlipidemic activity by measuring lipoprotein profiles secreted from human intestinal epithelium-like cells from the colon cancer cell line, Caco-2. Sodium (Na) butyrate at 5 mM differentiated Caco-2 cells into intestinal epithelium-like cells and numerous microvilli on the apical side of cells were observed under transmission electron microscopy.

Results

Conclusion