Water-soluble extract of Pacific Krill prevents triglyceride accumulation in adipocytes by suppressing PPARγ and C/EBPα expression.

Hidetoshi Yamada,Akira Yano,Tomohiro Ueda

doi:10.1371/journal.pone.0021952

Abstract

BackgroundPacific Krill (Euphausia pacifica) are small, red crustaceans, similar to shrimp, that flourish in the North Pacific and are eaten in Japan.Methods and FindingsWe investigated the effect of a water-soluble extract of Pacific Krill on adipocytes and discovered that this extract suppressed triglyceride accumulation in adipocytes. Furthermore, the water-soluble extract of Pacific Krill suppressed the expression of two master regulators of adipocyte differentiation, peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT enhancer binding protein alpha (C/EBPα). C/EBPβ promotes PPARγ and C/EBPα expression, but the water-soluble extract of Pacific Krill did not inhibit the expression of C/EBPβ or C/EBPβ-mediated transcriptional activation. The Pacific Krill extract was more effective than a PPARγ antagonist in suppressing PPARγ and C/EBPα expression.ConclusionsThese results indicated that the water-soluble extract of Pacific Krill was not simply a PPARγ antagonist, but that it prevented triglyceride accumulation in adipocytes by suppression of PPARγ and C/EBPα via a pathway that is independent of C/EBPβ.

Highlights

Obesity increases the likelihood of various diseases, including type 2 diabetes and cardiovascular diseases
These results indicated that the water-soluble extract of Pacific Krill was not a peroxisome proliferator-activated receptor gamma (PPARc) antagonist, but that it prevented triglyceride accumulation in adipocytes by suppression of PPARc and CCAAT enhancer binding protein alpha (C/EBPa) via a pathway that is independent of C/EBPb
To examine the effect of the water-soluble extract of Pacific Krill on preadipocytes proliferation, we cultured 3T3-F442A cells in insulin-free medium and counted the number of cells in the culture every 3 days to assess the influence of the water-soluble extract on preadipocyte proliferation

Summary

Introduction

Obesity increases the likelihood of various diseases, including type 2 diabetes and cardiovascular diseases. Foods that suppress absorption of glucose and lipids [1,2] and increase the metabolism of fat [3,4,5,6] are regarded as anti-obesity foods. Foods that prevent fat accumulation seem to be effective in preventing obesity, but only a few studies have investigated the foods that prevent fat accumulation. Adipose tissue is generally regarded as mesodermal in origin, and mature adipocytes develop from mesenchymal stem cells (MSCs) via a preadipocyte stage [7]. Increases in adipose tissue mass seem to depend on adipocyte hypertrophy because mature adipocytes have low proliferative potential. Adipogenesis and adipocyte hypertrophy may occur reiteratively as an individual becomes obese; inhibition of adipogenesis may be an effective approach to the prevention of fat accumulation. Pacific Krill (Euphausia pacifica) are small, red crustaceans, similar to shrimp, that flourish in the North Pacific and are eaten in Japan

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Results

Conclusion