Salyers Zachary R, Mariani Vinicius, Balestrieri Nicholas, Kumar Ravi A, Vugman Nicholas A, Thome Trace, Villani Katelyn R, Berceli Scott A, Scali Salvatore T, Vasilakos Georgios, Ryan Terence E
Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL.
Department of Surgery, University of Florida, Gainesville, FL.
JVS Vasc Sci. 2022 Apr 21;3:232-245. doi: 10.1016/j.jvssci.2022.03.003. eCollection 2022.
The objective of the present study was to determine whether elevated levels of S100A8 and S100A9 (S100A8/A9) alarmins contribute to ischemic limb pathology.
Gastrocnemius muscle was collected from control patients without peripheral arterial disease (PAD; n = 14) and patients with chronic limb threatening limb ischemia (CLTI; n = 14). Mitochondrial function was assessed in permeabilized muscle fibers, and RNA and protein analyses were used to quantify the S100A8/A9 levels. Additionally, a mouse model of hindlimb ischemia with and without exogenous delivery of S100A8/A9 was used.
Compared with the non-PAD control muscles, CLTI muscles displayed significant increases in the abundance of S100A8 and S100A9 at both mRNA and protein levels ( < .01). The CLTI muscles also displayed significant impairment in mitochondrial oxidative phosphorylation and increased mitochondrial hydrogen peroxide production compared with the non-PAD controls. The S100A8/A9 levels correlated significantly with the degree of muscle mitochondrial dysfunction ( < .05 for all). C57BL6J mice treated with recombinant S100A8/A9 displayed impaired perfusion recovery and muscle mitochondrial impairment compared with the placebo-treated mice after hindlimb ischemia surgery. These mitochondrial deficits observed after S100A8/A9 treatment were confirmed in the muscle cell culture system under normoxic conditions.
The S100A8/A9 levels were increased in CLTI limb muscle specimens compared with the non-PAD control muscle specimens, and the level of accumulation was associated with muscle mitochondrial impairment. Elevated S100A8/A9 levels in mice subjected to hindlimb ischemia impaired perfusion recovery and mitochondrial function. Together, these findings suggest that the inflammatory mediators S100A8/A9 might be directly involved in ischemic limb pathology.
本研究的目的是确定警报素S100A8和S100A9（S100A8/A9）水平升高是否会导致缺血性肢体病变。
从无外周动脉疾病（PAD；n = 14）的对照患者和患有慢性肢体威胁性缺血（CLTI；n = 14）的患者中采集腓肠肌。在通透的肌纤维中评估线粒体功能，并使用RNA和蛋白质分析来量化S100A8/A9水平。此外，使用了有或无外源性递送S100A8/A9的后肢缺血小鼠模型。
与非PAD对照肌肉相比，CLTI肌肉在mRNA和蛋白质水平上的S100A8和S100A9丰度均显著增加（P <.01）。与非PAD对照相比，CLTI肌肉在线粒体氧化磷酸化方面也表现出显著损伤，并且线粒体过氧化氢生成增加。S100A8/A9水平与肌肉线粒体功能障碍程度显著相关（所有P <.05）。与后肢缺血手术后接受安慰剂治疗的小鼠相比，接受重组S100A8/A9治疗的C57BL6J小鼠表现出灌注恢复受损和肌肉线粒体损伤。在常氧条件下的肌肉细胞培养系统中证实了S100A8/A9治疗后观察到的这些线粒体缺陷。
与非PAD对照肌肉标本相比，CLTI肢体肌肉标本中的S100A8/A9水平升高，且积累水平与肌肉线粒体损伤有关。后肢缺血小鼠中升高的S100A8/A9水平损害了灌注恢复和线粒体功能。总之，这些发现表明炎症介质S100A8/A9可能直接参与缺血性肢体病变。
