Barrault Christine, Garnier Julien, Pedretti Nathalie, Cordier-Dirikoc Sevda, Ratineau Emeline, Deguercy Alain, Bernard François-Xavier
BIOalternatives, 1 bis rue des Plantes, 86160 Gençay, France.
J Steroid Biochem Mol Biol. 2015 Aug;152:34-44. doi: 10.1016/j.jsbmb.2015.04.005. Epub 2015 Apr 9.
Androgens act through non-genomic and androgen receptor (AR)-dependent genomic mechanisms. AR is expressed in the sebaceous gland and the importance of androgens in the sebaceous function is well established. However, the in vitro models used to date have failed to evidence a clear genomic effect (e.g., modification of gene expression profile) of androgens on human sebocyte cells. In order to study the impact of active androgens in sebocytes, we constructed a stable human sebocyte cell line derived from SEBO662 [17] constitutively expressing a fully functional AR. In these SEBO662 AR+ cells, dihydrotestosterone (DHT) induced AR nuclear translocation and the strong modulation of a set of transcripts (RASD1, GREB1...) known to be androgen-sensitive in other androgenic cells and tissues. Moreover, we observed that DHT precociously down-regulated markers for immature follicular cells (KRT15, TNC) and for hair lineage (KRT75, FST) and up-regulated the expression of genes potentially related to sebocyte differentiation (MUC1/EMA, AQP3, FADS2). These effects were fully confirmed at the protein level. In addition, DHT-stimulated SEBO662 AR+, cultured in a low-calcium defined keratinocyte medium without serum or any complement, neosynthesize lipids, including sebum lipids, and store increased amounts of triglycerides in lipid droplets. DHT also induces morphological changes, increases cell size, and treatments over 7 days lead to a time-dependent increase in the population of apoptotic DNA-fragmented cells. Taken together, these results show for the first time that active androgens alone can engage immature sebocytes in a clear lipogenic differentiation process (Graphical abstract). These effects depend on the expression of a functional AR in these cells. This model should be of interest for revisiting the mechanisms of the sebaceous function in vitro and for the design of relevant pharmacological models for drug or compound testing.
雄激素通过非基因组和雄激素受体（AR）依赖性基因组机制发挥作用。AR在皮脂腺中表达，并且雄激素在皮脂腺功能中的重要性已得到充分证实。然而，迄今为止使用的体外模型未能证明雄激素对人皮脂腺细胞有明确的基因组效应（例如，基因表达谱的改变）。为了研究活性雄激素对皮脂腺细胞的影响，我们构建了一种稳定的人皮脂腺细胞系，该细胞系源自SEBO662 [17]，组成性表达功能齐全的AR。在这些SEBO662 AR +细胞中，双氢睾酮（DHT）诱导AR核转位，并强烈调节一组已知在其他雄激素细胞和组织中对雄激素敏感的转录本（RASD1、GREB1等）。此外，我们观察到DHT过早下调未成熟滤泡细胞（KRT15、TNC）和毛发谱系（KRT75、FST）的标志物，并上调可能与皮脂腺细胞分化相关的基因（MUC1 / EMA、AQP3、FADS2）的表达。这些效应在蛋白质水平上得到了充分证实。此外，在无血清或任何补体的低钙限定角质形成细胞培养基中培养的DHT刺激的SEBO662 AR +细胞重新合成脂质，包括皮脂脂质，并在脂滴中储存增加量的甘油三酯。DHT还诱导形态变化，增加细胞大小，并且超过7天的处理导致凋亡DNA片段化细胞群体随时间增加。综上所述，这些结果首次表明，活性雄激素单独作用就能使未成熟的皮脂腺细胞进入明确的生脂分化过程（图形摘要）。这些效应取决于这些细胞中功能性AR的表达。该模型对于重新审视体外皮脂腺功能机制以及设计用于药物或化合物测试的相关药理模型应该是有意义的。
