Comparison of Different Molecular Forms of Astaxanthin in Inhibiting Lipogenesis and its Mechanism

Astaxanthin is a natural active substance with a plurality of biological activities, such as anti-oxidation, anti-inflammatory and anti-cardio-cerebrovascular diseases. However, there is less research on the effects of astaxanthin on obesity. Astaxanthin with different structural forms affect the corresponding biological activity.The study aimed to compare Astaxanthin-octanoic acid diester (C8-AST) and Free Astaxanthin (F-AST) to explore the effect on lipogenesis in vitro.3T3-L1 preadipocytes were cultured under astaxanthin treatment. Cell proliferation and differentiation were evaluated by MTT assay and oil red O staining, respectively. The synthesis of metabolic mechanism of intracellular fatty acids and triglycerides was examined by qRT-PCR and Western blotting.C8-AST and F-AST had no effect on adipocyte proliferation at low concentration, but inhibited adipocyte differentiation. The treatment of astaxanthin could inhibit the expression of PPARγ, C/EBPα and SREBP-1c in adipocytes, up-regulate the expression of Wnt10b, LRP6, FZ in Wnt/ β-catenin signaling pathway and increase the β-catenin entry into nucleus, suggesting that the activation of Wnt/β-catenin signaling was involved in axtaxanthin-regulated lipogenesis. Notably, inhibition effect of lipogenesis on C8-AST was better than F-AST overall.At the cellular level, both two kinds of astaxanthins inhibit the synthesis of intracellular fatty acids and triglycerides. Notably, the inhibition effect of C8-AST is better than F-AST overall.