Fig. 8

Effect of CREB inhibitor (CREB inh) on autotaxin (ENPP2) expression, secretion, and activity in fibroblasts in response to medium conditioned by LPA-treated basal cells. Primary NHLF were treated with conditioned media from each of 3 non-smoking donors obtained in the presence or absence of 1.0 μg/ml LPA. For each condition, conditioned medium collected from cultures that were naive or treated with vehicle control (DMSO) or 200 nM CREB inhibitor (666-15) were collected and transferred to NHLF. Autotaxin, an enzyme responsible for the extracellular production of LPA, in encoded by ENPP2. Expression of the ENPP2 gene was assessed in fibroblasts 24 h after exposure to conditioned medium. Autotaxin protein levels and LPA levels were assessed in cell culture medium 24 h after exposure to conditioned medium. a ENPP2 mRNA levels. mRNA was measured by qRT-PCR using 18S RNA to normalize the samples. b Autotaxin protein levels. Protein levels were measured in cell culture medium by ELISA. c LPA levels. LPA was measured in cell culture medium by ELISA. Data are expressed as the mean value of the 3 donors ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001