Al Shamsi Mariam, Shahin Allen, Kamyan Doua, Alnaqbi Alanood, Shaban Sami, Souid Abdul-Kader
Department of Microbiology and Immunology, UAE University, College of Medicine and Health Sciences, Al Ain, P.O. Box 17666, Abu Dhabi, United Arab Emirates.
Department of Medical Education, UAE University, College of Medicine and Health Sciences, Al Ain, P.O. Box 17666, Abu Dhabi, United Arab Emirates.
Heliyon. 2021 Oct 4;7(10):e08111. doi: 10.1016/j.heliyon.2021.e08111. eCollection 2021 Oct.
We have previously reported that spinal cord respiration (cellular mitochondrial oxygen consumption) and ATP content are conserved in the studied model of experimental autoimmune encephalomyelitis (EAE), foreseeing a recovery of the diseased rats. This exemplary lesion of multiple sclerosis is used here to measure spinal cord bioenergetics in C57BL6 mice. Our hypothesis is that, despite the well-known focal axonal mitochondrial pathology, bioenergetics of the CNS is reasonably preserved in this disease.
EAE was induced with an immunodominant yelin ligodendrocyte lycoprotein epitope in complete Freund's adjuvant, appended by injections of pertussis toxin. A low- and high-dose of the encephalitogen, administered into base of tail or hind-flank, were investigated. Control mice received only the incomplete adjuvant into tail. Oxygen measurements were based on quenching the phosphorescence of Pd(II) meso-tetra (sulfophenyl) tetrabenzoporphyrin by molecular oxygen. Cellular ATP was measured using the luciferin/luciferase system.
The kinetics of spinal cord oxygen consumption was zero-order (linear with time) and inhibited by cyanide, confirming oxygen was reduced by cytochrome oxidase. The rate of respiration (in μM O.min.mg; measured on Days 13-28) in control mice was (mean ± SD) 0.086 ± 0.024 (n = 8) and in immunized mice was 0.079 ± 0.020 (n = 15, = 0.265, Mann-Whitney test). Consistently, cellular ATP (in μmol mg dry pellet weight; measured on Days 13-28) in control mice was 0.068 ± 0.079 (n = 11) and in immunized mice was 0.063 ± 0.061 (n = 24, = 0.887, Mann-Whitney U test).
measurements of spinal cord bioenergetics show conservation of the mitochondrial function in mice with EAE. These results suggest the previously documented reduced mitochondrial electrochemical potential in this disease is alterable, and likely reflects the adverse events of neuroinflammation.
我们之前报道过，在实验性自身免疫性脑脊髓炎（EAE）研究模型中，脊髓呼吸（细胞线粒体氧消耗）和ATP含量得以保留，预示患病大鼠会康复。多发性硬化症的这一典型病变在此用于测量C57BL6小鼠的脊髓生物能量学。我们的假设是，尽管存在众所周知的局灶性轴突线粒体病理学改变，但中枢神经系统的生物能量学在该疾病中仍能得到合理保留。
用完全弗氏佐剂中的免疫显性髓鞘少突胶质细胞糖蛋白表位诱导EAE，并注射百日咳毒素。研究了分别注入尾基部或后胁腹的低剂量和高剂量致脑炎原。对照小鼠仅在尾部注射不完全佐剂。氧测量基于分子氧淬灭Pd(II)中-四（磺苯基）四苯并卟啉的磷光。使用荧光素/荧光素酶系统测量细胞ATP。
脊髓氧消耗动力学为零级（与时间呈线性关系）且受氰化物抑制，证实氧由细胞色素氧化酶还原。对照小鼠的呼吸速率（以μM O.min.mg计；在第13 - 28天测量）为（平均值±标准差）0.086±0.024（n = 8），免疫小鼠为0.079±0.020（n = 15，P = 0.265，曼-惠特尼检验）。同样，对照小鼠的细胞ATP（以μmol mg干沉淀重量计；在第13 - 28天测量）为0.068±0.079（n = 11），免疫小鼠为0.063±0.061（n = 24，P = 0.887，曼-惠特尼U检验）。
脊髓生物能量学测量显示EAE小鼠的线粒体功能得以保留。这些结果表明，该疾病中先前记录的线粒体电化学势降低是可变的，且可能反映了神经炎症的不良事件。
