Antonovaite Nelda, Hulshof Lianne A, Hol Elly M, Wadman Wytse J, Iannuzzi Davide
Department of Physics and Astronomy and LaserLaB, VU Amsterdam, The Netherlands.
Department of Translational Neuroscience, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands.
J Mech Behav Biomed Mater. 2021 Jan;113:104159. doi: 10.1016/j.jmbbm.2020.104159. Epub 2020 Oct 28.
There is growing evidence that mechanical factors affect brain functioning. However, brain components responsible for regulating the physiological mechanical environment are not completely understood. To determine the relationship between structure and stiffness of brain tissue, we performed high-resolution viscoelastic mapping by dynamic indentation of the hippocampus and the cerebellum of juvenile mice brains, and quantified relative area covered by neurons (NeuN-staining), axons (neurofilament NN18-staining), astrocytes (GFAP-staining), myelin (MBP-staining) and nuclei (Hoechst-staining) of juvenile and adult mouse brain slices. Results show that brain subregions have distinct viscoelastic parameters. In gray matter (GM) regions, the storage modulus correlates negatively with the relative area of nuclei and neurons, and positively with astrocytes. The storage modulus also correlates negatively with the relative area of myelin and axons (high cell density regions are excluded). Furthermore, adult brain regions are ∼ 20%-150% stiffer than the comparable juvenile regions which coincide with increase in astrocyte GFAP-staining. Several linear regression models are examined to predict the mechanical properties of the brain tissue based on (immuno)histochemical stainings.
越来越多的证据表明，机械因素会影响大脑功能。然而，负责调节生理机械环境的大脑组成部分尚未完全明了。为了确定脑组织的结构与硬度之间的关系，我们通过对幼年小鼠大脑的海马体和小脑进行动态压痕试验，进行了高分辨率粘弹性图谱分析，并对幼年和成年小鼠脑切片中神经元（NeuN染色）、轴突（神经丝NN18染色）、星形胶质细胞（GFAP染色）、髓磷脂（MBP染色）和细胞核（Hoechst染色）覆盖的相对面积进行了量化。结果表明，脑亚区域具有不同的粘弹性参数。在灰质（GM）区域，储能模量与细胞核和神经元的相对面积呈负相关，与星形胶质细胞呈正相关。储能模量还与髓磷脂和轴突（排除高细胞密度区域）的相对面积呈负相关。此外，成年脑区域比相应的幼年区域硬约20%-150%，这与星形胶质细胞GFAP染色的增加相一致。我们研究了几种线性回归模型，以根据（免疫）组织化学染色预测脑组织的力学性能。
