Fig. 5

Epithelial and fibroblast cell viability and DNA damage response gene expression after 24-h challenge: (a) 20 μM curcumin treatment induces reduced viability in IPF-F (n = 4) and NHLF (n = 3) with significant effect on IPF epithelial cells (IPF-E n = 3) or A549 epithelial cells (n = 3). 10 mM NAC treatment induces reduced viability in epithelial cells but no significant effect in fibroblasts. Combination 10 mM NAC and 40 μM curcumin does not induce any change in cell viability as compared to untreated controls. (b) 20 μM curcumin induces significant increases in gene expression of p53 and p21 in all cell types. 10 mM NAC alone and in combination with 40 μM curcumin does not result in significant change to this gene expression in either epithelial or fibroblast cell lines. * indicates p value < 0.05