Abstract:

Yang Linfang, Cao Yuping, Zhang Mengli, Ma Pengcheng, Li Lingjun, Wei Jun, Tao Lei, Liu Weida. Department of Pharmacal Research, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China Corresponding author: Ma Pengcheng, Email: mpc815@163.com 【Abstract】 Objective To explore the effects of a novel retinoic acid ECPIRM and all-trans-retinoic acid （ATRA） on interleukin （IL）-1β expression in IL-17-stimulated human HaCaT keratinocytes. Methods Cultured HaCaT cells were classified into several groups: ECPIRM groups treated with 20 － 320 μmol/L ECPIRM for 24－72 hours, ATRA groups treated with 1 － 100 μmol/L ATRA for 24 － 72 hours, IL-17 group treated with 20 μg/L IL-17 for 24 hours, IL-17 ＋ ECPIRM group cotreated with 20 μg/L IL-17 and 80 μmol/L ECPIRM for 24 hours, IL-17 ＋ ATRA group cotreated with 20 μg/L IL-17 and 5 μmol/L ATRA for 24 hours, control group treated with the solvent solution of IL-17. Then, methyl thiazolyl tetrazolium （MTT） assay was performed to evaluate cellular proliferative activity in these groups, enzyme-linked immunosorbent assay （ELISA） to measure the level of IL-1β protein in the culture supernatant of HaCaT cells, quantitative fluorescent PCR to detect the mRNA expression of IL-1β in HaCaT cells. Data were statistically analyzed by using one-way analysis of variance （ANOVA） followed by the least significant difference （LSD） test. Results The treatments with ECPIRM of 20 and 40 μmol/L for 24 hours could promote the proliferation of HaCaT cells. However, with the increase in treatment duration and concentrations, ECPIRM inhibited the growth of HaCaT cells in a concentration- and time-dependent manner. ATRA also decelerated the proliferation of HaCaT cells in a concentration- and time-dependent manner. The levels of supernatant IL-1β protein and intracellular IL-1β mRNA were both significantly higher in the IL-17 group than in the control group （IL-1β protein: 20.312 ± 2.053 ng/L vs. 11.427 ± 0.929 ng/L, P < 0.05; IL-1β mRNA: 4.05 ± 0.47 vs. 1 ± 0.03, P < 0.05）, but significantly lower in the IL-17 ＋ ECPIRM group （12.470 ± 1.897 ng/L and 0.82 ± 0.12 respectively, both P < 0.05） and IL-17 ＋ ATRA group （12.694 ± 1.478 ng/L and 0.87 ± 0.16, respectively, both P < 0.05） than in the IL-17 group, and similar among the ATRA groups, ECPIRM groups and control group （both P > 0.05）. Conclusion IL-17 can promote the secretion of IL-1β by HaCaT cells, while ECPIRM and ATRA can significantly inhibit the IL-17-induced IL-1β secretion.