Centre for the Cellular Microenvironment, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
Tissue Engineering Research Group, Department of Anatomy and Regenerative Medicine, Royal College of Surgeons in Ireland, Dublin D2, Ireland.
Sci Adv. 2021 Feb 26;7(9). doi: 10.1126/sciadv.abb7921. Print 2021 Feb.
Bioactive metabolites have wide-ranging biological activities and are a potential source of future research and therapeutic tools. Here, we use nanovibrational stimulation to induce osteogenic differentiation of mesenchymal stem cells, in the absence of off-target, nonosteogenic differentiation. We show that this differentiation method, which does not rely on the addition of exogenous growth factors to culture media, provides an artifact-free approach to identifying bioactive metabolites that specifically and potently induce osteogenesis. We first identify a highly specific metabolite, cholesterol sulfate, an endogenous steroid. Next, a screen of other small molecules with a similar steroid scaffold identified fludrocortisone acetate with both specific and highly potent osteogenic-inducing activity. Further, we implicate cytoskeletal contractility as a measure of osteogenic potency and cell stiffness as a measure of specificity. These findings demonstrate that physical principles can be used to identify bioactive metabolites and then enable optimization of metabolite potency can be optimized by examining structure-function relationships.
生物活性代谢物具有广泛的生物学活性，是未来研究和治疗工具的潜在来源。在这里，我们使用纳米振动刺激来诱导间充质干细胞的成骨分化，而不会产生脱靶的非成骨分化。我们表明，这种不依赖于向培养基中添加外源性生长因子的分化方法，为鉴定特异性和强效诱导成骨的生物活性代谢物提供了一种无假象的方法。我们首先鉴定出一种高度特异性的代谢物胆固醇硫酸盐，一种内源性类固醇。接下来，对具有相似甾体支架的其他小分子进行筛选，发现醋酸氟氢可的松具有特异性和成骨诱导活性。此外，我们将细胞骨架收缩性作为成骨效力的度量，将细胞刚性作为特异性的度量。这些发现表明，可以利用物理原理来鉴定生物活性代谢物，然后通过检查结构-功能关系来优化代谢物的效力。
