Figure 4

Bilberry and anthocyanidins inhibit the insulin signaling pathway. (A) 3T3-L1 preadipocytes were treated with DMSO, bilberry extracts (100 μ g/mL) or delphynidin (100 nM), and then stimulated with or without insulin (100 nM) for 5 min. Protein levels of IRS1 and pIRS1 were analyzed by western blot analysis. Band densities were quantified using Image Gauge 4.22 image analysis software. Protein levels are expressed as fraction of control (DMSO treated and without insulin stimulation cells) level. (B) Top significant pathways of the genes commonly altered in the "Bilberry", "Delphinidin" and "Cyanidin" by GSEA (Fisher's exact test). (C) The hypothetical scheme of a mechanism that anthocyanidins-enriched bilberry extracts inhibit adipocyte differentiation via insulin signal.