It was reported that oral administration of glucosylceramide (GlcCer) from plants ameliorates skin barrier function. GlcCer is a type of glycosphingolipid that exists widely as a component of the cell membrane. However, the mechanism of improvement by dietary GlcCer is not completely understood. The aim of the present study was to investigate the mechanism of GlcCer in the improvement of skin barrier function. Five-week-old male Hos:HR-1 mice were divided into three groups fed on standard diet, unsaturated fatty acids-deficient (HR-AD) diet, and HR-AD diet supplemented with 0.1% P-GlcCer diet. Skin barrier function was evaluated by transepidermal water loss (TEWL) value and wrinkle formation. The effect of transforming growth factor-β (TGF-β) on skin barrier function and collagen content in skin was examined using exogenous TGF-β and its neutralizing antibody. TEWL value and wrinkle formation were decreased by oral administration of pineapple (P)-GlcCer. Not only the TGF-β contents in serum and skin but also hydroxyproline content reduced by the HR-AD diet were restored by P-GlcCer administration. Exogenous TGF-β ameliorated both skin barrier function and collagen contents. However, the improvement of skin barrier function by P-GlcCer was cancelled and collagen content in skin was also decreased by TGF-β antibody injection. Recovery of TGF-β content by P-GlcCer contributed to the production of collagen in skin, resulting in improved skin barrier function.

中文翻译：

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口服菠萝葡萄糖神经酰胺可通过恢复皮肤中TGF-β的水平降低来改善表皮屏障功能障碍

据报道，口服植物中的葡萄糖基神经酰胺（GlcCer）可改善皮肤屏障功能。GlcCer是一类糖鞘脂，广泛存在于细胞膜中。但是，饮食中的GlcCer改善的机制尚不完全清楚。本研究的目的是研究GlcCer改善皮肤屏障功能的机制。五周大的雄性Hos：HR-1小鼠分为三组，分别接受标准饮食，不饱和脂肪酸缺乏（HR-AD）饮食和补充0.1％P-GlcCer饮食的HR-AD饮食。通过表皮失水（TEWL）值和皱纹形成来评估皮肤屏障功能。使用外源性TGF-β及其中和抗体检查了转化生长因子-β（TGF-β）对皮肤屏障功能和皮肤胶原蛋白含量的影响。口服菠萝（P）-GlcCer可降低TEWL值和皱纹形成。通过施用P-GlcCer，不仅可以恢复血清和皮肤中的TGF-β含量，还可以通过HR-AD饮食降低羟脯氨酸的含量。外源性TGF-β改善了皮肤屏障功能和胶原蛋白含量。然而，通过注射TGF-β抗体，P-GlcCer取消了对皮肤屏障功能的改善，皮肤中的胶原蛋白含量也降低了。通过P-GlcCer恢复TGF-β含量有助于皮肤中胶原蛋白的产生，从而改善了皮肤屏障功能。口服菠萝（P）-GlcCer可降低TEWL值和皱纹形成。通过施用P-GlcCer，不仅可以恢复血清和皮肤中的TGF-β含量，还可以通过HR-AD饮食降低羟脯氨酸的含量。外源性TGF-β改善了皮肤屏障功能和胶原蛋白含量。然而，通过注射TGF-β抗体，P-GlcCer取消了对皮肤屏障功能的改善，皮肤中的胶原蛋白含量也降低了。通过P-GlcCer恢复TGF-β含量有助于皮肤中胶原蛋白的产生，从而改善了皮肤屏障功能。口服菠萝（P）-GlcCer可降低TEWL值和皱纹形成。通过施用P-GlcCer，不仅可以恢复血清和皮肤中的TGF-β含量，还可以通过HR-AD饮食降低羟脯氨酸的含量。外源性TGF-β改善了皮肤屏障功能和胶原蛋白含量。然而，通过注射TGF-β抗体，P-GlcCer取消了对皮肤屏障功能的改善，皮肤中的胶原蛋白含量也降低了。通过P-GlcCer恢复TGF-β含量有助于皮肤中胶原蛋白的产生，从而改善了皮肤屏障功能。然而，通过注射TGF-β抗体，P-GlcCer取消了对皮肤屏障功能的改善，皮肤中的胶原蛋白含量也降低了。通过P-GlcCer恢复TGF-β含量有助于皮肤中胶原蛋白的产生，从而改善了皮肤屏障功能。然而，通过注射TGF-β抗体，P-GlcCer取消了对皮肤屏障功能的改善，皮肤中的胶原蛋白含量也降低了。通过P-GlcCer恢复TGF-β含量有助于皮肤中胶原蛋白的产生，从而改善了皮肤屏障功能。