Serum affects keratinization and tight junctions in three-dimensional cultures of the mouse keratinocyte cell line COCA through retinoic acid receptor-mediated signaling
Serum affects keratinization and tight junctions in three-dimensional cultures of the mouse keratinocyte cell line COCA through retinoic acid receptor-mediated signaling
复制标题
血清通过视黄酸受体介导的信号传导影响小鼠角质形成细胞系 COCA 三维培养物中的角化和紧密连接
DOI：
10.1007/s00418-018-1741-2
复制
发表时间：
2018
影响因子：
2.3
通讯作者：
Inai Tetsuichiro
中科院分区：
文献类型：
--
作者：
Ozaki Akane;Otani Takahito;Kitagawa Norio;Ogata Kayoko;Iida Hiroshi;Kojima Hiroshi;Inai Tetsuichiro
维生素A存在于血清中，已知会影响角质形成细胞的增殖、表皮分化和角质化。在小鼠中，口腔、食道和前胃中的复层上皮被角化；然而，在人类中，这些上皮不角化。一些研究报道，在含血清的培养液中三维培养的人角质形成细胞可以形成角化上皮。在此，我们评估了血清对小鼠角质形成细胞3D培养中分化标志物和紧密连接蛋白的形态、表达和定位以及细胞旁通透性的影响。我们发现，只有0.1%的缺钙血清抑制角化，并诱导分化标志蛋白从氯化蛋白到角蛋白4的表达变化；抑制维甲酸受体介导的信号转导逆转了这些变化。此外，该血清降低了Claudin-1蛋白的表达，并阻止了其在3D培养表面的occludin阳性点上的定位。另一方面，血清增加了Claudin-4、occludin、阻滞带-1和E-cadherin的蛋白表达。这些变化可能有助于减少大约一半的跨上皮电阻值。总之，来自表皮的小鼠角质形成细胞在3D培养中形成了非角化结构，以响应血清中的维生素A。结果提示，维甲酸受体介导的信号转导可能在小鼠口腔、食道和前胃以及表皮中的上皮细胞中受到抑制，导致这些上皮细胞的角质化。
Vitamin A, which is found in serum, is known to affect keratinocyte proliferation, epidermal differentiation, and keratinization. In mice, stratified epithelia in the oral cavity, esophagus, and forestomach are keratinized; however, these epithelia are not keratinized in humans. Several studies have reported that three-dimensional (3D) cultures of human keratinocytes in serum-containing medium could form keratinized epithelia. Here, we evaluated the effects of serum on the morphology, expression, and localization of differentiation markers and tight junction proteins, and paracellular permeability in 3D cultures of mouse keratinocytes. We found that only 0.1% calcium-depleted serum inhibited keratinization and induced a change in the expression of differentiation marker proteins from loricrin to keratin 4; the inhibition of retinoic acid receptor-mediated signaling reversed these changes. Furthermore, the serum reduced claudin-1 protein expression and prevented its localization at occludin-positive spots on the surface of 3D cultures. On the other hand, the serum increased the protein expression of claudin-4, occludin, zonula occludens-1, and E-cadherin. These changes may contribute to the reduction of the transepithelial electrical resistance by approximately half. In conclusion, mouse keratinocytes derived from the epidermis formed non-keratinized structures in 3D cultures in response to vitamin A in serum. The results suggest that retinoic acid receptor-mediated signaling may be inhibited in the mouse epithelia in the oral cavity, esophagus, and forestomach as well as the epidermis, leading to the keratinization of these epithelia.