Attenuation of Adipogenesis and Lipogenesis by Baby Ginger in 3T3L1 Adipocytes

Abstract

Abstract Objectives To determine the phenolic content and anti-oxidation properties of ginger at different harvesting time and to test its effects on lipid droplet and triglyceride formation, and expression of genes for adipogenesis and lipogenesis in 3T3L1 adipocytes. Methods The biweekly ginger samples for 16 weeks were freeze dried and then extracted in 80% Methanol. The total phenolic content was determined using the Folin- Ciocalteu method and analysis of antioxidation activity was determined using 2, 2- Diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS•+) chemical assays and 2’, 7’-Dichlorodihydrofluorescin diacetate (DCFH-DA cellular method. The ginger samples were analyzed to determine major phytochemicals including gingerol, paradol, and shogaol, using a HPLC system. The effect of baby ginger on lipid droplet formation in 3T3 adipocytes was determined using Oil Red'O staining and concentration of Triglycerides was assayed using a commercial kit. Expression of CREPB1, C/EBPβ, and PPARγ genes for adipogenesis and ACC and PEPCK genes for lipogenesis was determined by qRT-PCR. Results Ginger has the highest content of phenolic compounds and superior anti-oxidation activity when harvested early (baby ginger); however, the concentration of phenolic compounds and its anti-oxidation activity were progressively reduced up to 50% as ginger matures. Furthermore, ginger reduced oil droplet accumulation by 25%-40% in a dose dependent manner, which consequently resulted in 50% inhibition of triglycerides accumulation in the adipocytes. Ginger treatment of 3T3 cells inhibited expression of adipogenesis genes CEBPβ and PPARγ and lipogenesis genes ACC and PEPCK. Conclusions Our results suggest harvesting of ginger at appropriate (early) time to optimize or maintain the qualitative and quantitative levels of biological active compounds. The data also suggest that a regular use of ginger can potentially lower incidences of obesity and obesity-related complications, a growing concern in the USA. Funding Sources The Center for Agricultural Research, Engagement & Outreach (CAREO), Virginia State University.