title: Anti-adipogenic activity of the edible brown alga Ecklonia stolonifera and its constituent fucosterol in 3T3-L1 adipocytes.
abstract: Fucosterol is a sterol metabolite of brown algae and regulates genes involved with cholesterol homeostasis. As a part of our continuous search for anti-obesity agents from natural marine sources, the anti-adipogenic activities of Ecklonia stolonifera and its sterol, fucosterol, were evaluated for the inhibition of adipocyte differentiation and lipid formation. Oil Red O staining was used to evaluate triglyceride contents in 3T3-L1 pre-adipocytes primed by differentiation medium (DM) I and DM II. The methanolic extract of E. stolonifera showed strong anti-adipogenic activity, and was thus fractionated with several solvents. Among the tested fractions, the dichloromethane (CH2Cl2) fraction was found to be the most active fraction, with significant inhibition (40.5 %) of intracellular lipid accumulation at a non-toxic concentration, followed by the ethyl acetate fraction (30.2 %) at the same concentration, while the n-butanol and water fractions did not show inhibitory activity within the tested concentrations. The strong anti-adipogenic CH2Cl2-soluble fraction was further purified by a repeated chromatography to yield fucosterol. Fucosterol reduced lipid contents in a concentration-dependent manner without showing any cytotoxicity. Fucosterol treatment also yielded a decrease in the expression of the adipocyte marker proteins peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα) in a concentration-dependent manner. Taken together, these results suggest that fucosterol inhibits expression of PPARγ and C/EBPα, resulting in a decrease of lipid accumulation in 3T3-L1 pre-adipocytes, indicating that the potential use of E. stolonifera and its bioactive fucosterol as an anti-obesity agent.
authors.affiliation: Department of Food Science and Human Nutrition, Chonbuk National University, Jeonju, 561-756, Republic of Korea.
authors.forename: Hyun Ah
authors.initials: HA
authors.lastname: Jung
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Jung
authors.forename: Hyun Young
authors.initials: HY
authors.lastname: Jeong
authors.forename: Hyun Ju
authors.initials: HJ
authors.lastname: Kwon
authors.forename: Min-Sun
authors.initials: MS
authors.lastname: Kim
authors.forename: Jae Sue
authors.initials: JS
authors.lastname: Choi
mesh_terms: D041721:3T3-L1 Cells / Q000187:drug effects* / Q000502:physiology; D017667:Adipocytes / Q000187:drug effects* / Q000502:physiology; D050156:Adipogenesis / Q000187:drug effects* / Q000502:physiology; D000818:Animals; D019440:Anti-Obesity Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D051379:Mice; D000459:Phaeophyceae; D013265:Stigmasterol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D019440:Anti-Obesity Agents; C015896:fucosterol; D013265:Stigmasterol