Leptin regulates keratin 17 expression in HaCaT human keratinocytes / 中华皮肤科杂志

ABSTRACT

Objective To evaluate the effect of leptin on K17 expression in HaCaT human keratinocytes.Methods Some cultured HaCaT cells were treated with leptin (100 ng/ml) or remained untreated for 24 hours followed by the quantification of K17 mRNA expression by real-time PCR and detection of K17 protein expression by Western blot and immunofluorescence staining.To investigate the action mechanism of leptin,some cultured HaCaT cells were divided into several groups to be treated with leptin (100 ng/ml) alone,Piceatannol (an inhibitor of the STAT3 pathway) + leptin (100 ng/ml),PD-98059 (an inhibitor of the Erk1/2 pathway) + leptin (100 ng/ml),respectively for 24 hours,with the cells receiving no treatment as the negative control.Subsequently,the mRNA and protein expressions of K17 were measured by the above methods.Statistical analysis was done by the two-sample ttest.Results The mRNA expression of K17 was significantly higher in HaCaT cells treated with leptin alone than in those remaining untreated (3.086 7 ± 0.186 1 vs.1.000 0 ± 0.000 0,P ＜ 0.01),but significantly downregulated in HaCaT cells treated with Piceatannol + leptin and those with PD-98059 + leptin compared with those treated leptin alone (0.674 1 ± 0.060 0 and 0.855 0 ± 0.390 3 vs.2.242 7 ± 0.188 7,both P ＜ 0.01).The results of Western blot and immunofluorescence staining were in agreement with those of real-time PCR.Conclusions Leptin can induce K17 expression in HaCaT cells,likely by activating the STAT3 and Erk1/2 signaling pathways.