羟基红花黄色素A通过抑制程序性坏死减轻小鼠重症中暑引起的急性肺损伤

目的 研究羟基红花黄色素A(HSYA)是否在重症中暑肺损伤中起保护作用及其可能的作用机制。方法 使用不同浓度（1.125、2.25、4.5 mg/kg）HSYA腹腔注射预处理小鼠，建立重症中暑（sHS）小鼠模型，分为低、中、高剂量HSYA中暑组、单纯中暑组及正常对照组，12只/组。初步观察及比较各组热耐受的情况，以确定HSYA最佳治疗剂量；后使用中剂量HSYA及RIP1活化抑制剂Nec-1预处理小鼠，分组为HSYA+HS组、Nec-1+HS组、HS组及正常对照组，8只/组，观察72 h恢复期核心体温变化特征，比较热耐受情况及生存情况。给予相同处理因素处理小鼠分组为正常对照组，HS组，HSYA+HS组及Nec-1+HS组，正常对照组6只，其余18只/组，分别于重症中暑恢复期不同阶段（0、2、6、12、24 h）处死小鼠，每个时间点处死3只小鼠，收集小鼠的肺组织、肺泡灌洗液及血液样本，取肺组织行HE染色，并进行病理评分，检测肺湿干重比，肺含水量，肺泡灌洗液中白细胞、中性粒细胞、蛋白含量；ELISA法检测肺泡灌洗液中HMGB1水平及血清中TNF-α、IL-6及HMGB1水平；Western ...

Hydroxysafflor yellow A attenuates heat stroke-induced acute lung injury in mice by inhibiting necroptosis

Objective To investigate the protective effect of hydroxysafflor yellow A (HSYA) against heat stroke (HS)-induced acute lung injury and its possible mechanism. Methods The optimal dose of HSYA pretreatment via intraperitoneal injection prior to HS was determined in a mice by observing heat tolerance of the mice. C57BL/6J mice were pretreated with HSYA at the optimal dose or with Nec-1 (a RIP1 activation inhibitor) before HS, and the changes in core body temperature and survival of the mice were observed during the 72-h recovery period. At different stages of recovery, lung tissues, bronchoalveolar lavage fluid and blood samples were collected from the mice for assessing lung tissue pathology, wet-to-dry weight ratio and water content of the lungs; leukocyte and neutrophil counts, total protein levels and HMGB1 level in the bronchoalveolar lavage fluid (BLF) were also detected. Serum levels of TNF-α, IL-6 and HMGB1 were detected with ELISA, and the expression levels of RIP1, RIP3, MLKL-s358, MLKL and MLKL-s358 proteins in the lung tissues were detected using Western blotting. Results HSYA pretreatment at the moderate and high doses significantly improved heat tolerance of the mice with comparable effects. At the optimal dose of 2.25 mg/kg, HSYA pretreatment significantly increased heat tolerance of the mice (P<0.05), showing a similar effect with Nec-1 pretreatment. Pretreatment with HSYA and Nec-1 both significantly increased survival rate of the mice (P<0.05), lowered histopathological score and water content of the lungs, and reduced the levels of TNF-α, IL-6 and HMGB1 (P<0.05), leukocyte and neutrophil counts, and total protein and HMGB1 levels in the BLF (P<0.05). The mice during recovery from HS showed significantly increased RIP1 expression and MLKL-s358 phosphorylation level in the lung tissue (P<0.05), which were obviously lowered by HSYA pretreatment of the mice. Conclusion Severe HS results in necroptosis in the lung tissue of mice, which can be alleviated by HSYA pretreatment.