N-乙酰半胱氨酸上调Sirtuin 3蛋白表达对脓毒症小鼠急性肾损伤的保护作用及机制研究北大核心CSCD

目的探讨抗氧化剂N-乙酰半胱氨酸(NAC)调控沉默信息调节因子3(Sirt3)对脓毒症致小鼠急性肾损伤(AKI)的保护作用及其机制。方法将雄性C57BL/6小鼠随机(随机数字法)分为假手术组(Sham)、盲肠结扎和穿孔术组(CLP)CLP+NAC(50 mg/kg)和CLP+NAC(100mg/kg)组,每组10只;CLP造模后24h处死小鼠,留取血液和肾组织样本;采用HE染色法评估各组小鼠肾组织病理损伤;ELISA法检测血清中肌酐(Scr)尿素氮(BUN)、肾损伤分子1(KIM-1)和中性粒细胞明胶酶相关载脂蛋白(NGAL)水平;采用免疫组织化学检测肾组织Sirt3蛋白表达;RT-qPCR法测定Sirt3 mRNA水平;透射电镜下观察肾小管上皮细胞线粒体损伤情况,并计算线粒体密度,同时检测肾皮质中超氧化物歧化酶(SOD)谷胱甘肽过氧化物酶(GSH-Px)过氧化氢酶(CAT)和丙二醛(MDA)水平。结果与Sham组相比,CLP导致肾组织病理损伤明显加重(P<0.001),肾功能指标Scr、BUN、KIM-1和NGAL水平均明显升高(均P<0.001),肾组织Sirt3蛋白和mRNA表达均显著降低(均P<0.001),肾小管上皮细胞线粒体结构破坏增加,线粒体密度的明显减低(P<0.001),肾皮质中抗氧化酶SOD、GSH-Px和CAT水平均显著降低(均P<0.001),同时脂质过氧化物MDA显著升高(P<0.001)。与CLP组相比,虽然50 mg/kg NAC预处理组肾损伤评分、肾功能指标Scr、BUN、KIM-1和NGAL水平均有所降低,肾组织中SOD,GSH-Px和CAT的水平均有所升高,但差异无统计学意义。然而,给予100 mg/kg NAC预处理可显著降低CLP引起的肾组织病理损伤(P<0.001),并且均明显降低Scr、BUN、KIM-1和NGAL水平(均P<0.001),显著升高肾组织Sirt3蛋白[(50.20±2.79)vs.(20.00±0.75),P<0.001]和mRNA[(0.57±0.07)vs.(0.41±0.07),P<0.001]表达水平,肾小管上皮细胞线粒体结构更加稳定,线粒体密度明显增加[(0.60±0.05)vs.(0.43±0.06),P<0.001],均显著升高SOD(U/mg)[(67.37±3.79)vs.(21.09±0.89),P<0.001]、GSH-Px(U/mg)[(265.61±9.61)vs.(180.00±3.31),P<0.001]和CAT(U/mg)[(8.58±0.65)vs.(5.19±0.58),P<0.001]水平,同时明显降低MDA(U/mg)表达水平[(40.36±1.79)vs.(83.81±1.70),P<0.001]。结论NAC可通过上调Sirt3蛋白表达显著降低脓毒症小鼠肾组织病理损伤、改善肾功能、维持线粒体结构稳定和降低氧化应激水平,对CLP诱发AKI具有显著的保护作用。     

Evaluation the efficacy and safety of N-acetylcysteine inhalation spray in controlling the symptoms of patients with COVID-19: An open-label randomized controlled clinical trial

The aim of this study was to evaluate the effect and safety of N-acetylcysteine (NAC) inhalation spray in the treatment of patients with coronavirus disease 2019 (COVID-19). This randomized controlled clinical trial study was conducted on patients with COVID-19. Eligible patients (n = 250) were randomly allocated into the intervention group (routine treatment + NAC inhaler spray one puff per 12 h, for 7 days) or the control group who received routine treatment alone. Clinical features, hemodynamic, hematological, biochemical parameters and patient outcomes were assessed and compared before and after treatment. The mortality rate was significantly higher in the control group than in the intervention group (39.2% vs. 3.2%, p < 0.001). Significant differences were found between the two groups (intervention and control, respectively) for white blood cell count (6.2 vs. 7.8, p < 0.001), hemoglobin (12.3 vs. 13.3, p = 0.002), C-reactive protein (CRP: 6 vs. 11.5, p < 0.0001) and aspartate aminotransferase (AST: 32 vs. 25.5, p < 0.0001). No differences were seen for hospital length of stay (11.98 ± 3.61 vs. 11.81 ± 3.52, p = 0.814) or the requirement for intensive care unit (ICU) admission (7.2% vs. 11.2%, p = 0.274). NAC was beneficial in reducing the mortality rate in patients with COVID-19 and inflammatory parameters, and a reduction in the development of severe respiratory failure; however, it did not affect the length of hospital stay or the need for ICU admission. Data on the effectiveness of NAC for Severe Acute Respiratory Syndrome Coronavirus-2 is limited and further research is required.