Department of Biochemistry, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel.
Red Blood Cell Research Group, Vetsuisse Faculty, Institute of Veterinary Physiology, University of Zurich, 8057 Zürich, Switzerland.
Int J Mol Sci. 2024 May 27;25(11):5814. doi: 10.3390/ijms25115814.
The deformability of red blood cells (RBCs), expressing their ability to change their shape as a function of flow-induced shear stress, allows them to optimize oxygen delivery to the tissues and minimize their resistance to flow, especially in microcirculation. During physiological aging and blood storage, or under external stimulations, RBCs undergo metabolic and structural alterations, one of which is hemoglobin (Hb) redistribution between the cytosol and the membrane. Consequently, part of the Hb may attach to the cell membrane, and although this process is reversible, the increase in membrane-bound Hb (MBHb) can affect the cell's mechanical properties and deformability in particular. In the present study, we examined the correlation between the MBHb levels, determined by mass spectroscopy, and the cell deformability, determined by image analysis. Six hemoglobin subunits were found attached to the RBC membranes. The cell deformability was negatively correlated with the level of four subunits, with a highly significant inter-correlation between them. These data suggest that the decrease in RBC deformability results from Hb redistribution between the cytosol and the cell membrane and the respective Hb interaction with the cell membrane.
红细胞（RBCs）的变形性，即其随血流切应力变化改变形状的能力，使其能够优化向组织输送氧气，并最大限度地降低其在微循环中的流动阻力。在生理老化和血液储存过程中，或在外部刺激下，RBCs 会发生代谢和结构改变，其中之一是血红蛋白（Hb）在细胞质和细胞膜之间的重新分布。因此，部分 Hb 可能附着在细胞膜上，尽管这个过程是可逆的，但细胞膜结合 Hb（MBHb）的增加会特别影响细胞的机械性能和变形性。在本研究中，我们通过质谱法测定了 MBHb 水平，并通过图像分析测定了细胞的变形性，研究了两者之间的相关性。发现有六个血红蛋白亚基附着在 RBC 膜上。细胞的变形性与四个亚基的水平呈负相关，它们之间具有高度显著的相关性。这些数据表明，RBC 变形性的降低是由于 Hb 在细胞质和细胞膜之间的重新分布以及相应的 Hb 与细胞膜的相互作用所致。
