Commercial Fucoidans from Fucus vesiculosus Can Be Grouped into Antiadipogenic and Adipogenic Agents

Abstract

Fucus vesiculosus is a brown seaweed used in the treatment of obesity. This seaweed synthesizes various bioactive molecules, one of them being a sulfated polysaccharide known as fucoidan (FF). This polymer can easily be found commercially, and has antiadipogenic and lipolytic activity. Using differential precipitation with acetone, we obtained four fucoidan-rich fractions (F0.5/F0.9/F1.1/F2.0) from FF. These fractions contain different proportions of fucose:glucuronic acid:galactose:xylose:sulfate, and also showed different electrophoretic mobility and antioxidant activity. Using 3T3-L1 adipocytes, we found that all samples had lipolytic action, especially F2.0, which tripled the amount of glycerol in the cellular medium. Moreover, we observed that FF, F1.0, and F2.0 have antiadipogenic activity, as they inhibited the oil red staining by cells at 40%, 40%, and 50%, respectively. In addition, they decreased the expression of key proteins of adipogenic differentiation (C/EBPα, C/EBPβ, and PPARγ). However, F0.5 and F0.9 stimulated the oil red staining at 80% and increased the expression of these proteins. Therefore, these fucoidan fractions have an adipogenic effect. Overall, the data show that F2.0 has great potential to be used as an agent against obesity as it displays better antioxidant, lipolytic and antiadipogenic activities than the other fucoidan fractions that we tested.

Fucoidan Characterization: Determination of Purity and Physicochemical and Chemical Properties

“…As developed by Dodgson and Price, sulfate content can be analyzed on the basis of barium sulfate (BaSO 4 ) precipitation after the addition of barium chloride (BaCl 2 ) in gelatin using sodium sulfate (Na 2 SO 4 ) or potassium sulfate (K 2 SO 4 ) [ 86 , 87 ]. The sulfate amount is determined by turbidimetry at 500 nm [ 88 ]. Since sulfate ester groups are susceptible to hydrolysis, turbidimetric analysis requires preliminary liberation of the sulfate groups via acid hydrolysis using 4 M HCl at 100 °C for 6 h [ 89 ] or 2 M trifluoroacetic acid (TFA) at 100 °C for 8 h [ 90 ].…”

“…The detection of sugar monomers in polysaccharides is conducted after the step of acid hydrolysis [ 129 ], e.g., heating at 90–121 °C for 2–4 h with 4 M trifluoroacetic acid (TFA), applied for the isolation of sulfated galactofucan from the sporophyll of U. pinnatifida [ 130 ], 2 M HCl, applied for the commercial fucoidans of F. vesiculosus [ 88 ], and the two-step sulfuric acid treatment for 60 min with 72% H 2 SO 4 at 30 °C followed by hydrolysis for 60 min in 4% H 2 SO 4 , applied for the crude fucoidans isolated from Saccharina latissima and Laminaria digitata [ 129 , 131 ]. Afterward, the hydrolysate is neutralized, filtered, and subjected to a liquid chromatography (HPLC) step, using different reference sugar monomers, such as arabinose, fructose, fucose, galactose, glucose, glucosamine, mannose, and xylose.…”

Fucoidans: Downstream Processes and Recent Applications

“…Therefore, they can be extracted from the pre-treated biomass using a simple hot-or cold-water incubation. Afterwards, the extracted fucoidans can be precipitated by high volumes of solvents with a low dielectric constant (e.g., >70% (v/v), > 2.5 volume ethanol [111,112], <2 volume acetone [113]) or cationic surfactants (e.g., hexadecyltrimethylammonium bromide (Cetavlon ® ) 10% (v/v)) [55] via an affinity complex formation at low temperatures (4 • C) to remove the undesired salts from the sulfated polysaccharides [52]. This specific precipitation reaction between fucoidans and Cetavlon ® is applied in screening tests of microorganisms for putative fucoidanase activity [114].…”

Astaxanthin as a Peroxisome Proliferator-Activated Receptor (PPAR) Modulator: Its Therapeutic Implications

“…In addition to its major role in glucose and lipid homeostasis, PPARγ is also associated with inflammatory responses, cardiovascular diseases, neurogenerative diseases, ocular diseases, and cancer [11]. Since these various physiological functions of PPARs can serve as therapeutic targets for the treatment of chronic diseases, researchers have studied synthetic and naturally occurring substances, as well as marine organisms, to identify specific ligands that modulate PPAR activities [12,13,14,15,16,17,18,19,20,21].…”