Figure 4.
Blocking FFaR2 prevents fermentation-mediated collagen type I and p-ERK induction in a mouse skin model. Mouse skin was subcutaneously injected with FFaR2 (siFFaR2) or scrambled siRNA 20 min prior to the topical application of fermented media from S. epidermidis (ATCC 12228) (107 CFU/mL) in the presence of CIN 2%. (a) Protein expression analyzed by the Western blot analysis of collagen type I and β-actin, and the ratio of intensities of collagen type I relative to β-actin. (b) The expression of the FFaR2 gene relative to the GAPDH gene as analyzed by RT-PCR analysis in mouse skin from all the above groups. (c) The schema of CIN 2% fermentation by S. epidermidis, which produces BA that further activates pERK1/2 via FFaR2 in fibroblast cells, ultimately stimulating the synthesis of collagen type I in a mouse skin model. Data are expressed as means ± SD (** p < 0.05; *** p < 0.005; n = 3).