Department of Emergency, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China; Lawson Health Research Institute, London Health Sciences Centre, London, Ontario, Canada N6A 4G5; Department of Pathology and Laboratory Medicine, Western University, London, Ontario, Canada N6A 4G5.
Lawson Health Research Institute, London Health Sciences Centre, London, Ontario, Canada N6A 4G5; Department of Pathology and Laboratory Medicine, Western University, London, Ontario, Canada N6A 4G5; Department of Medicine, Western University, London, Ontario, Canada N6A 4G5; Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, China.
Free Radic Biol Med. 2018 Aug 1;123:125-137. doi: 10.1016/j.freeradbiomed.2018.05.073. Epub 2018 May 24.
Sepsis-caused multiple organ failure remains the major cause of morbidity and mortality in intensive care units. Nicotinamide riboside (NR) is a precursor of nicotinamide adenine dinucleotide (NAD), which is important in regulating oxidative stress. This study investigated whether administration of NR prevented oxidative stress and organ injury in sepsis.
Mouse sepsis models were induced by injection of lipopolysaccharides (LPS) or feces-injection-in-peritoneum. NR was given before sepsis onset. Cultured macrophages and endothelial cells were incubated with various agents.
Administration of NR elevated the NAD levels, and elicited a reduction of oxidative stress, inflammation and caspase-3 activity in lung and heart tissues, which correlated with attenuation of pulmonary microvascular permeability and myocardial dysfunction, leading to less mortality in sepsis models. These protective effects of NR were associated with decreased levels of plasma high mobility group box-1 (HMGB1) in septic mice. Consistently, pre-treatment of macrophages with NR increased NAD content and reduced HMGB1 release upon LPS stimulation. NR also prevented reactive oxygen species (ROS) production and apoptosis in endothelial cells induced by a conditioned-medium collected from LPS-treated macrophages. Furthermore, inhibition of SIRT1 by EX527 offset the negative effects of NR on HMGB1 release in macrophages, and ROS and apoptosis in endothelial cells.
Administration of NR prevents lung and heart injury, and improves the survival in sepsis, likely by inhibiting HMGB1 release and oxidative stress via the NAD/SIRT1 signaling. Given NR has been used as a health supplement, it may be a useful agent to prevent organ injury in sepsis.
脓毒症引起的多器官功能衰竭仍然是重症监护病房发病率和死亡率的主要原因。烟酰胺核糖(NR)是烟酰胺腺嘌呤二核苷酸(NAD)的前体,在调节氧化应激中很重要。本研究探讨了烟酰胺核糖(NR)是否能预防脓毒症中的氧化应激和器官损伤。
通过注射脂多糖(LPS)或腹腔内注射粪便来诱导小鼠脓毒症模型。在脓毒症发作前给予 NR。用不同的药物孵育巨噬细胞和内皮细胞。
NR 的给药提高了 NAD 水平,并减少了肺和心脏组织中的氧化应激、炎症和 caspase-3 活性,这与肺微血管通透性和心肌功能障碍的减轻相关,导致脓毒症模型中的死亡率降低。NR 的这些保护作用与脓毒症小鼠血浆高迁移率族蛋白 B1(HMGB1)水平降低有关。同样,NR 预处理巨噬细胞可减少 LPS 刺激后 HMGB1 的释放。NR 还可防止来自 LPS 处理的巨噬细胞的条件培养基诱导的内皮细胞中活性氧(ROS)的产生和凋亡。此外,SIRT1 的抑制剂 EX527 抵消了 NR 对巨噬细胞中 HMGB1 释放、ROS 和内皮细胞凋亡的负向作用。
NR 的给药可预防肺和心脏损伤,并提高脓毒症的存活率,可能是通过抑制 HMGB1 释放和氧化应激来实现的,因为 NAD/SIRT1 信号通路。鉴于 NR 已被用作保健品,它可能是预防脓毒症中器官损伤的有用药物。