One of the major difference between the in vivo and in vitro embryonic environments is the stiffness of the culture substrate. Xanthan gum (XG) and locust bean gum (LBG) are natural materials that are safe, inexpensive and easy to handle. In this study, we investigated the effects of using a polysaccharide culture substrate made from 1% XG and 1% LBG (XG‐LBG gel) on bovine embryonic development. Oocytes collected from bovine ovaries were subjected to maturation, and fertilization to generate embryos at an early developmental stage (>4 cell stage). Cleaved embryos were further cultured in a well of 96‐well cell culture plate coated with or without XG‐LBG gel for 5 days. While the developmental rate up to the blastocyst stage did not differ between the two culture systems (control, 38.0 vs. gel, 38.6%), blastocysts developed on the XG‐LBG gel produced significantly high cell numbers and ATP content. Embryos cultured on XG‐LBG gels for 24 hr had high expression levels of F‐actin and a highly even distribution of E‐cadherin. In addition, embryos developed on XG‐LBG gel demonstrated increased translocation of YAP to the nucleus and increased connective tissue growth factor (CTGF) protein levels (downstream of Hippo signalling). These findings suggest that soft culture substrates improve embryonic development by enhancing mechanotransduction, including YAP‐CTGF signalling.

中文翻译：

---

黄原胶和刺槐豆胶的底物可改善牛胚胎的发育。

体内和体外胚胎环境之间的主要区别之一是培养基质的硬度。黄原胶（XG）和刺槐豆胶（LBG）是安全，便宜且易于处理的天然材料。在这项研究中，我们调查了使用由1％XG和1％LBG（XG‐LBG凝胶）制成的多糖培养底物对牛胚胎发育的影响。从牛卵巢收集的卵母细胞经过成熟，并受精以在早期发育阶段（> 4细胞阶段）产生胚胎。切开的胚胎在装有或不带有XG-LBG凝胶的96孔细胞培养板的孔中进一步培养5天。虽然两种培养系统在胚泡期之前的发育率没有差异（对照，凝胶比分别为38.0和38.6％），在XG‐LBG凝胶上发育的胚泡产生的细胞数量和ATP含量明显较高。在XG-LBG凝胶上培养24小时的胚胎具有高水平的F-肌动蛋白表达和高度均匀的E-钙粘着蛋白分布。此外，在XG-LBG凝胶上发育的胚胎表现出YAP向核的易位增加和结缔组织生长因子（CTGF）蛋白质水平的升高（河马信号的下游）。这些发现表明，软文化底物可通过增强机械传导，包括YAP-CTGF信号传导，来改善胚胎发育。XG-LBG凝胶上发育的胚胎显示出YAP向核的转运增加，结缔组织生长因子（CTGF）蛋白水平增加（河马信号的下游）。这些发现表明，软文化底物可通过增强机械传导，包括YAP-CTGF信号传导，来改善胚胎发育。XG-LBG凝胶上发育的胚胎显示出YAP向核的转运增加，结缔组织生长因子（CTGF）蛋白水平增加（河马信号的下游）。这些发现表明，软文化底物可通过增强机械传导，包括YAP-CTGF信号传导，来改善胚胎发育。