Murine sickle cell disease (SCD) results in damage to multiple organs, likely mediated first by vasculopathy. While the mechanisms inducing vascular damage remain to be determined, nitric oxide bioavailability and sterile inflammation are both considered to play major roles in vasculopathy. Here, we investigate the effects of high mobility group box-1 (HMGB1), a pro-inflammatory damage-associated molecular pattern (DAMP) molecule on endothelial-dependent vasodilation and lung morphometrics, a structural index of damage in sickle (SS) mice. SS mice were treated with either phosphate-buffered saline (PBS), hE-HMGB1-BP, an hE dual-domain peptide that binds and removes HMGB1 from the circulation the liver, 1-[4-(aminocarbonyl)-2-methylphenyl]-5-[4-(1-imidazol-1-yl)phenyl]-1-pyrrole-2-propanoic acid (N6022) or N-acetyl-lysyltyrosylcysteine amide (KYC) for three weeks. Human umbilical vein endothelial cells (HUVEC) were treated with recombinant HMGB1 (r-HMGB1), which increases -nitrosoglutathione reductase (GSNOR) expression by ∼80%, demonstrating a direct effect of HMGB1 to increase GSNOR. Treatment of SS mice with hE-HMGB1-BP reduced plasma HMGB1 in SS mice to control levels and reduced GSNOR expression in arteries isolated from SS mice by ∼20%. These changes were associated with improved endothelial-dependent vasodilation. Treatment of SS mice with N6022 also improved vasodilation in SS mice suggesting that targeting GSNOR also improves vasodilation. SCD decreased protein nitrosothiols (SNOs) and radial alveolar counts (RAC) and increased GSNOR expression and mean linear intercepts (MLI) in lungs from SS mice. The marked changes in pulmonary morphometrics and GSNOR expression throughout the lung parenchyma in SS mice were improved by treating with either hE-HMGB1-BP or KYC. These data demonstrate that murine SCD induces vasculopathy and chronic lung disease by an HMGB1- and GSNOR-dependent mechanism and suggest that HMGB1 and GSNOR might be effective therapeutic targets for reducing vasculopathy and chronic lung disease in humans with SCD.

中文翻译：

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无菌炎症诱发小鼠镰状细胞病的血管病变和慢性肺损伤

鼠镰状细胞病 (SCD) 会导致多个器官受损，可能首先由血管病变介导。虽然诱导血管损伤的机制仍有待确定，但一氧化氮生物利用度和无菌炎症都被认为在血管病变中发挥着重要作用。在这里，我们研究了高迁移率族盒-1 (HMGB1)（一种促炎损伤相关分子模式 (DAMP) 分子）对内皮依赖性血管舒张和肺形态测量（镰刀 (SS) 小鼠损伤的结构指数）的影响。 SS 小鼠接受磷酸盐缓冲盐水 (PBS)、hE-HMGB1-BP（一种结合肝脏循环并将 HMGB1 去除的 hE 双结构域肽）、1-[4-(氨基羰基)-2-甲基苯基] 治疗-5-[4-(1-咪唑-1-基)苯基]-1-吡咯-2-丙酸 (N6022) 或 N-乙酰基-赖氨酰酪氨酰半胱氨酸酰胺 (KYC) 三周。用重组 HMGB1 (r-HMGB1) 处理人脐静脉内皮细胞 (HUVEC)，可使 β-亚硝基谷胱甘肽还原酶 (GSNOR) 表达增加约 80%，证明 HMGB1 对增加 GSNOR 具有直接作用。用 hE-HMGB1-BP 处理 SS 小鼠，可将 SS 小鼠血浆 HMGB1 降低至对照水平，并将 SS 小鼠分离的动脉中 GSNOR 表达降低约 20%。这些变化与内皮依赖性血管舒张的改善有关。用 N6022 治疗 SS 小鼠也改善了 SS 小鼠的血管舒张，这表明靶向 GSNOR 也改善了血管舒张。 SCD 降低了 SS 小鼠肺中的蛋白质亚硝基硫醇 (SNO) 和径向肺泡计数 (RAC)，并增加了 GSNOR 表达和平均线性截距 (MLI)。通过 hE-HMGB1-BP 或 KYC 治疗，SS 小鼠肺形态学和整个肺实质 GSNOR 表达的显着变化得到改善。这些数据表明，小鼠 SCD 通过 HMGB1 和 GSNOR 依赖性机制诱发血管病变和慢性肺部疾病，并表明 HMGB1 和 GSNOR 可能是减少 SCD 人类血管病变和慢性肺部疾病的有效治疗靶点。