在响应生理学相关的pH波动时,对原蛋白水凝结构和特性进行多模式的表征
Orit Bronner-Shtrauchler1, Einat Nativ-Roth2, Daniel Sevilla Sanchez2
1Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer Sheva, Israel.
Acta biomaterialia
|February 28, 2024
概括
细胞外基质 (ECM) pH 的变化改变了原蛋白的结构和特性. 酸性条件会导致方向失调和机械强度降低,但中性pH值会恢复原生原蛋白的特性.
科学领域:
- 生物材料科学 生物材料科学
- 生物物理学的生物物理.
- 细胞生物学 细胞生物学
背景情况:
- 细胞外基质 (ECM) 主要由原组成,对组织结构和功能至关重要.
- 病理状况,如固体瘤和慢性伤口,在ECM内涉及显著的pH波动.
- 之前的研究集中在原形成 (纤维形成) 期间的pH影响上,而不是预先形成的原结构.
研究的目的:
- 研究pH值波动对预制原体水凝结构,特性和功能的影响.
- 了解微环境pH值的变化如何影响水合原体,模仿生理ECM.
- 在疾病相关的pH条件下分析原干扰.
主要方法:
- 使用I型原蛋白水凝来模拟生理ECM.
- 使用冷扫描电子显微镜 (cryo-SEM) 进行水合原蛋白的高分辨率成像.
- 应用人工智能辅助图像分析以量化结构变化.
- 测量质性质,包括储存模量和透性.
主要成果:
- 尽管存在相关的pH值变化,但原蛋白的二次结构仍然稳定.
- 与生理pH相比,将pH值降低到6.5会导致原纤维较短,稀少,且失方向.
- 原蛋白水凝在pH 7和7.8时表现出较高的储存模量和较低的透率,而不是pH 6.5和7.4.
- 将酸性原蛋白恢复到中性的pH值恢复了它的原生结构和粘弹性特性.
结论:
- 微环境的pH波动显著改变了原纤维的形态和机械特性.
- 这些由pH诱导的原结构变化可以是可逆的.
- 了解这些依赖pH值的原蛋白变化为涉及ECM变化的疾病提供了潜在的治疗策略.
相关概念视频
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