Modulation of Inflammatory Gene Expression by a Bilberry (Vaccinium myrtillus L.) Extract and Single Anthocyanins Considering Their Limited Stability under Cell Culture Conditions

Studies with nonintestinal models indicate that anthocyanin-rich extracts can modulate inflammatory gene expression and may help prevent development of inflammatory bowel diseases (IBD). This work investigated the influence of a bilberry (Vaccinium myrtillus L.) extract (BE) and comprising anthocyanins on pro-inflammatory genes in IFN-gamma/IL-1 beta/TNF-alpha stimulated human colon epithelial cells (T84) by qRT-PCR and cytokine arrays. Moreover, the stability of selected anthocyanins under cell culture conditions was examined to assess their anti-inflammatory properties. BE and single anthocyanins significantly inhibited the expression and secretion of IBD-associated pro-inflammatory mediators (TNF-alpha, IP-10, I-TAC, sICAM-1, GRO-alpha) in the stimulated cells. The anti-inflammatory activity thereby strongly depends on the aglycon structure (hydroxylation and methylation pattern) and the sugar moiety. In contrast to anthocyanidins, which were highly unstable in cell culture medium, suggesting that their degradation products might contribute to the inhibitory effects assigned to the parent compounds, anthocyanins have higher stability and may directly contribute to BE's effects.