Jagiellonian Centre for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
Jagiellonian Centre for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland; Faculty of Chemistry, Jagiellonian University, 2 Gronostajowa St., 30-387 Krakow, Poland.
Spectrochim Acta A Mol Biomol Spectrosc. 2023 Jan 5;284:121819. doi: 10.1016/j.saa.2022.121819. Epub 2022 Sep 3.
In the present study, we characterized the secondary structure alterations of intact red blood cells (RBCs) cytosol with special attention to the sex-related alterations in 8- and 24-week-old female and male ApoE/LDLR mice, compared to age-matched female and male C57BL/6J control animals. Results were obtained with previously established methodology based on Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Additionally, we evaluated 2,3-DPG levels in the RBCs and showed its potential link to the hemoglobin (Hb) secondary structure alterations. Considering Hb structure alterations probed by FTIR-ATR, the ratio of turns to α-helices in 8-week-old ApoE/LDLR mice suggested more pronounced secondary structure alterations within the RBCs than in the age-matched control. Sex-related differences were observed solely in 24-week-old male ApoE/LDLR mice, which showed statistically significant increase in the secondary structure alterations compared to 24-week-old female ApoE/LDLR mice. Similar to the secondary structure alterations, no sex-related differences were observed in the levels of 2,3-DPG in RBCs, except for 24-week-old male ApoE/LDLR mice, which showed significantly higher levels compared to the age-matched female ApoE/LDLR mice. Considering the age-related alterations, we observed significant increases in the intracellular 2,3-DPG of RBCs with animals' age in all studied groups, except for female ApoE/LDLR mice, where a significant difference was not reported. This suggests the clear correlation between secondary structure of Hb alterations and 2,3-DPG levels for male and female murine RBC and proves a higher resistance of older female RBCs to the secondary structure changes with progression of atherosclerosis. Moreover, it may be concluded that higher 2,3-DPG levels in RBCs occurred in response to the secondary structure alterations of Hb in ApoE/LDLR mice.
在本研究中，我们特别关注 8 周和 24 周龄雌性和雄性 ApoE/LDLR 小鼠与同龄雌性和雄性 C57BL/6J 对照动物之间的性别相关变化，对完整红细胞（RBC）胞质的二级结构变化进行了表征。结果是使用先前基于傅里叶变换红外光谱-衰减全反射（FTIR-ATR）建立的方法获得的。此外，我们评估了 RBC 中的 2,3-DPG 水平，并显示其与血红蛋白（Hb）二级结构变化的潜在联系。考虑到 FTIR-ATR 探测到的 Hb 结构变化，8 周龄 ApoE/LDLR 小鼠的转角与α-螺旋的比值表明 RBC 中的二级结构变化比同龄对照更为明显。仅在 24 周龄雄性 ApoE/LDLR 小鼠中观察到性别相关差异，与 24 周龄雌性 ApoE/LDLR 小鼠相比，其二级结构变化具有统计学意义。与二级结构变化类似，除了 24 周龄雄性 ApoE/LDLR 小鼠外，RBC 中的 2,3-DPG 水平没有观察到性别相关差异，与同龄雌性 ApoE/LDLR 小鼠相比，其水平明显更高。考虑到与年龄相关的变化，我们观察到在所有研究组中，随着动物年龄的增长，RBC 中的细胞内 2,3-DPG 显著增加，除了雌性 ApoE/LDLR 小鼠，因为没有报道显著差异。这表明 Hb 二级结构变化与 2,3-DPG 水平之间存在明显的相关性，适用于雄性和雌性鼠 RBC，并证明了随着动脉粥样硬化的进展，老年雌性 RBC 对二级结构变化具有更高的抵抗力。此外，可以得出结论，ApoE/LDLR 小鼠中 Hb 二级结构变化导致 RBC 中的 2,3-DPG 水平升高。
