Marom Anat, Berkovitch Yulia, Toume Samer, Alvarez-Elizondo Martha B, Weihs Daphne
Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
Clin Biomech (Bristol). 2019 Feb;62:96-103. doi: 10.1016/j.clinbiomech.2019.01.009. Epub 2019 Jan 28.
Sustained, low- and mid-level (3-6%), radial stretching combined with varying concentrations of sodium pyruvate (NaPy) supplement increase the migration rate during microscale gap closure following an in vitro injury; NaPy is a physiological supplement often used in cell-culture media. Recently we showed that low-level tensile strains accelerate in vitro kinematics during en masse cell migration; topically applied mechanical deformations also accelerate in vivo healing in larger wounds. The constituents and nutrients at injury sites change. Thus, we combine a supplement with stretching conditions to effectively accelerate wound healing.
Monolayers of murine fibroblasts (NIH3T3) or myoblasts (C2C12) were cultured in 1 mM NaPy on stretchable, linear-elastic substrates. Monolayers were subjected to 0, 3, or 6% stretching using a custom three-dimensionally printed stretching apparatus, micro-damage was immediately induced, media was replaced with fresh media containing 0, 1, or 5 mM NaPy, and cell migration kinematics during gap-closure were quantitatively evaluated.
In myoblasts, the smallest evaluated strain (3%, minimal risk of damage) combined with preinjury (1 mM) and post-injury exogenous NaPy supplements accelerated gap closure in a statistically significant manner; response was NaPy concentration dependent. In both fibroblasts and myoblasts, when cells were pre-exposed to NaPy, yet no supplement was provided post-injury, mid-level stretches (6%) compensated for post-injury deficiency in exogenous NaPy and accelerated gap-closure in a statistically significant manner.
Small deformations combined with NaPy supplement prior-to and following cell-damage accelerate en masse cell migration and can be applied in wound healing, e.g. to preventatively accelerate closure of microscale gaps.
持续的低水平和中等水平（3%-6%）的径向拉伸，结合不同浓度的丙酮酸钠（NaPy）补充剂，可提高体外损伤后微尺度间隙闭合过程中的迁移率；NaPy是细胞培养基中常用的一种生理补充剂。最近我们发现，低水平拉伸应变可加速成组细胞迁移过程中的体外运动学；局部施加的机械变形也可加速较大伤口的体内愈合。损伤部位的成分和营养物质会发生变化。因此，我们将一种补充剂与拉伸条件相结合，以有效加速伤口愈合。
将小鼠成纤维细胞（NIH3T3）或成肌细胞（C2C12）单层培养在含有1 mM NaPy的可拉伸线性弹性基质上。使用定制的三维打印拉伸装置对单层细胞进行0%、3%或6%的拉伸，立即诱导微损伤，用含有0 mM、1 mM或5 mM NaPy的新鲜培养基替换培养基，并定量评估间隙闭合过程中的细胞迁移运动学。
在成肌细胞中，评估的最小应变（3%，损伤风险最小）与损伤前（1 mM）和损伤后外源性NaPy补充剂相结合，以统计学显著方式加速了间隙闭合；反应呈NaPy浓度依赖性。在成纤维细胞和成肌细胞中，当细胞预先暴露于NaPy，但损伤后未提供补充剂时，中等水平的拉伸（6%）补偿了损伤后外源性NaPy的不足，并以统计学显著方式加速了间隙闭合。
细胞损伤前后的小变形与NaPy补充剂相结合可加速成组细胞迁移，可应用于伤口愈合，例如预防性地加速微尺度间隙的闭合。
