Figure 3.

LPLI reduces fibrotic gene expression via the cAMP signalling pathway. HGFs were cultured in the absence or presence of arecoline(200 μmol·L⁻¹), forskolin (60 μmol·L⁻¹), and SQ22536(100 μmol·L⁻¹), and the cells were treated with or without LPLI (8 J·cm⁻²). The mRNA expression levels of the fibrotic marker genes, CCN2, and α-SMA were examined by qRT-PCR at day 5. (a) α-SMA mRNA expression. (b) CCN2 mRNA expression. The data are shown as the mean±standard deviation. The statistical levels are indicated as follows: *P<0.05 compared with the arecoline group, and ^#P<0.05 compared with the indicated group. HGF, human gingival fibroblast; LPLI, low-power laser irradiation; mRNA, messenger RNA; qRT-PCR, quantitative reverse transcription PCR; SMA, smooth muscle actin.