Sahin Afsun, Liu Yang, Kam Wendy R, Darabad Raheleh Rahimi, Sullivan David A
Schepens Eye Research Institute of Massachusetts Eye and Ear and Department of Ophthalmology, Harvard Medical School, Boston, MA, USA; Department of Ophthalmology, Koc University Medical School, Istanbul, Turkey.
Schepens Eye Research Institute of Massachusetts Eye and Ear and Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
Ocul Surf. 2020 Apr;18(2):199-205. doi: 10.1016/j.jtos.2020.02.006. Epub 2020 Feb 27.
We discovered that dihydrotestosterone (DHT) decreases the ability of lipopolysaccharide, a bacterial toxin, to stimulate the secretion of leukotriene B4, a potent proinflammatory mediator, by immortalized human meibomian gland epithelial cells (IHMGECs). We hypothesize that this hormone action reflects an androgen suppression of proinflammatory gene activity in these cells. Our goal was to test this hypothesis. For comparison, we also examined whether DHT treatment elicits the same effect in immortalized human corneal (IHC) and conjunctival (IHConj) ECs.
Differentiated cells were cultured in media containing vehicle or 10 nM DHT. Cells (n = 3 wells/treatment group) were then processed for RNA isolation and the analysis of gene expression by using Illumina BeadChips, background subtraction, cubic spline normalization and Geospiza software.
Our results demonstrate that DHT significantly suppressed the expression of numerous immune-related genes in HMGECs, such as those associated with antigen processing and presentation, innate and adaptive immune responses, chemotaxis, and cytokine production. DHT also enhanced the expression of genes for defensin β1, IL-1 receptor antagonist, and the anti-inflammatory serine peptidase inhibitor, Kazal type 5. In contrast, DHT had no effect on proinflammatory gene expression in HCECs, and significantly increased 33 gene ontologies linked to the immune system in HConjECs.
Our findings support our hypothesis that androgens suppress proinflammatory gene expression in IHMGECs. This hormone effect may contribute to the typical absence of inflammation within the human meibomian gland.
我们发现二氢睾酮（DHT）可降低脂多糖（一种细菌毒素）刺激永生化人睑板腺上皮细胞（IHMGECs）分泌白三烯B4（一种强效促炎介质）的能力。我们推测这种激素作用反映了雄激素对这些细胞中促炎基因活性的抑制。我们的目标是验证这一推测。为作比较，我们还研究了DHT处理对永生化人角膜（IHC）和结膜（IHConj）上皮细胞是否有同样的作用。
将分化的细胞培养于含赋形剂或10 nM DHT的培养基中。然后对细胞（每个处理组n = 3孔）进行RNA提取，并使用Illumina BeadChips、背景扣除、三次样条归一化和Geospiza软件分析基因表达。
我们的结果表明，DHT显著抑制了HMGECs中众多免疫相关基因的表达，如那些与抗原加工呈递、固有和适应性免疫反应、趋化性及细胞因子产生相关的基因。DHT还增强了防御素β1、白细胞介素-1受体拮抗剂及抗炎性丝氨酸蛋白酶抑制剂Kazal 5型基因的表达。相比之下，DHT对HCECs中促炎基因的表达没有影响，且显著增加了HConjECs中与免疫系统相关的33个基因本体。
我们的研究结果支持了我们的推测，即雄激素抑制IHMGECs中促炎基因的表达。这种激素效应可能有助于解释人睑板腺内典型的无炎症状态。
