Fokam Danielle, Dickson Kayle, Kamali Kiyana, Holbein Bruce, Colp Patricia, Stueck Ashley, Zhou Juan, Lehmann Christian
Department of Physiology and Biophysics, Dalhousie University, Halifax, NS B3H 1X5, Canada.
Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 1X5, Canada.
Antibiotics (Basel). 2020 May 26;9(6):283. doi: 10.3390/antibiotics9060283.
Iron is an essential element for various physiological processes, but its levels must remain tightly regulated to avoid cellular damage. Similarly, iron plays a dual role in systemic inflammation, such as with sepsis. Leukocytes utilize iron to produce reactive oxygen species (ROS) to kill bacteria, but pathologically increased iron-catalyzed ROS production in sepsis can lead to damage of host cells, multi-organ failure and death. Temporary reduction in bioavailable iron represents a potential therapeutic target in sepsis. This study investigates the effect of the novel iron chelator, DIBI, in murine models of systemic (hyper-)inflammation: C57BL/6 mice were challenged with toxins from Gram-positive (: lipoteichoic acid, peptidoglycan) and Gram-negative bacteria ( and : lipopolysaccharide). Intravital microscopy (IVM) was performed to assess immune cell activation and its impact on microvascular blood flow in vivo in the microcirculation of the gut. Plasma inflammatory mediators were measured via multiplex assay, and morphologic change in intestinal tissue was evaluated. DIBI treatment decreased leukocyte (hyper-)activation induced by Gram-positive and Gram-negative toxins. In some cases, it preserved capillary perfusion, reduced plasma inflammatory markers and attenuated tissue damage. These findings support the utility of DIBI as a novel treatment for systemic inflammation, e.g., sepsis.
铁是各种生理过程必需的元素,但其水平必须严格调控以避免细胞损伤。同样,铁在全身炎症(如脓毒症)中发挥双重作用。白细胞利用铁产生活性氧(ROS)以杀灭细菌,但脓毒症中铁催化的ROS生成病理性增加可导致宿主细胞损伤、多器官功能衰竭和死亡。生物可利用铁的暂时减少是脓毒症潜在的治疗靶点。本研究调查新型铁螯合剂DIBI在全身(超)炎症小鼠模型中的作用:用革兰氏阳性菌(脂磷壁酸、肽聚糖)和革兰氏阴性菌(脂多糖)的毒素攻击C57BL/6小鼠。进行活体显微镜检查(IVM)以评估免疫细胞活化及其对肠道微循环中体内微血管血流的影响。通过多重分析测定血浆炎症介质,并评估肠道组织的形态学变化。DIBI治疗可降低革兰氏阳性和革兰氏阴性毒素诱导的白细胞(超)活化。在某些情况下,它可维持毛细血管灌注、降低血浆炎症标志物并减轻组织损伤。这些发现支持DIBI作为全身炎症(如脓毒症)新型治疗方法的效用。