Institute of Veterinary Biochemistry, Freie Universität Berlin, Germany.
Am J Physiol Gastrointest Liver Physiol. 2011 Aug;301(2):G260-8. doi: 10.1152/ajpgi.00304.2010. Epub 2011 May 12.
Ruminal epithelium adapts to dietary change with well-coordinated alterations in metabolism, proliferation, and permeability. To further understand the molecular events controlling diet effects, the aim of this study was to evaluate protein expression patterns of ruminal epithelium in response to various feeding regimes. Sheep were fed with a concentrate-supplemented diet for up to 6 wk. The control group received hay only. Proteome analysis with differential in gel electrophoresis technology revealed that, after 2 days, 60 proteins were significantly modulated in ruminal epithelium in a comparison between hay-fed and concentrate-fed sheep (P < 0.05). Forty proteins were upregulated and 20 proteins were downregulated in response to concentrate diet. After 6 wk of this diet, only 14 proteins were differentially expressed. Among these, 11 proteins were upregulated and 3 downregulated. To identify proteins that were modulated by dietary change, two-dimensional electrophoresis was coupled with liquid chromatography electrospray ionization mass spectrometry. The differential expression of selected proteins, such as esterase D, annexin 5, peroxiredoxin 6, carbonic anhydrase I, and actin-related protein 3, was verified by immunoblotting and/or mRNA analysis. The identified proteins were mainly associated with functions related to cellular stress, metabolism, and differentiation. These results suggest new candidate proteins that may contribute to a better understanding of the signaling pathways and mechanisms that mediate rumen epithelial adaptation to high-concentrate diet.
瘤胃上皮通过代谢、增殖和通透性的协调改变来适应饮食变化。为了进一步了解控制饮食影响的分子事件，本研究旨在评估瘤胃上皮对各种饲养方式的蛋白质表达模式。绵羊用添加浓缩物的饲料喂养长达 6 周。对照组仅喂干草。差异凝胶电泳技术的蛋白质组分析显示，在干草喂养和浓缩物喂养绵羊之间的比较中，2 天后，瘤胃上皮中有 60 种蛋白质的表达显著调节（P<0.05）。40 种蛋白质上调，20 种蛋白质下调以响应浓缩物饮食。在这种饮食 6 周后，只有 14 种蛋白质表达差异。其中，11 种蛋白质上调，3 种下调。为了鉴定受饮食变化调节的蛋白质，二维电泳与液相色谱电喷雾电离质谱联用。通过免疫印迹和/或 mRNA 分析验证了选定蛋白质（如酯酶 D、膜联蛋白 5、过氧化物还原酶 6、碳酸酐酶 I 和肌动蛋白相关蛋白 3）的差异表达。鉴定出的蛋白质主要与与细胞应激、代谢和分化相关的功能有关。这些结果表明了新的候选蛋白质，它们可能有助于更好地理解调节瘤胃上皮适应高浓缩饲料的信号通路和机制。
