Chang Ping, Mo Bing, Cauvi David M, Yu Ying, Guo Zhenhui, Zhou Jian, Huang Qiong, Yan Qitao, Chen Guiming, Liu Zhanguo
Department of ICU, Zhujiang Hospital of Southern Medical University , Guangzhou, Guangdong , China.
Department of Surgery, University of California San Diego , La Jolla, CA , USA.
PeerJ. 2017 Mar 21;5:e3108. doi: 10.7717/peerj.3108. eCollection 2017.
Apoptosis of lymphocytes is associated with immunosuppression and poor prognosis in sepsis. Our previous report showed that histones, nuclear proteins released from damaged or dying cells in sepsis, can mediate lymphocyte apoptosis via mitochondria damage. Grape seed proanthocyanidin extract (GSPE), a natural substance with protective properties against oxidative stress, plays a vital role in cell and mitochondria protection. We thus hypothesized that GSPE may play a protective role in histone-induced lymphocyte apoptosis through its anti-oxidative properties. In this study, we investigated the protective efficacy of GSPE on lymphocyte apoptosis induced by extracellular histones, a main contributor of death in sepsis. Human blood lymphocytes were treated with 50 μg/ml histones, 2 μg/ml GSPE, or a combination of both. A total of 100 μM -acetylcysteine (NAC), a reactive oxygen species (ROS) inhibitor, was used as a positive control for GSPE. Apoptosis, intracellular ROS levels, mitochondrial membrane potential, Bcl-2 expression, and caspase-3 cleavage were measured. Our data clearly indicate that GSPE significantly inhibited lymphocyte apoptosis, generation of ROS, the loss of mitochondrial membrane potential, the decrease in Bcl-2 expression, and caspase-3 activation induced by extracellular histones. In conclusion, we show that GSPE has a protective effect on lymphocyte apoptosis induced by extracellular histones. This study suggests GSPE as a potential therapeutic agent that could help reduce lymphocyte apoptosis, and thus the state of immunosuppression was observed in septic patients.
淋巴细胞凋亡与脓毒症中的免疫抑制和不良预后相关。我们之前的报告显示，组蛋白是脓毒症中受损或濒死细胞释放的核蛋白，可通过线粒体损伤介导淋巴细胞凋亡。葡萄籽原花青素提取物（GSPE）是一种具有抗氧化应激保护特性的天然物质，在细胞和线粒体保护中起着至关重要的作用。因此，我们推测GSPE可能通过其抗氧化特性在组蛋白诱导的淋巴细胞凋亡中发挥保护作用。在本研究中，我们研究了GSPE对细胞外组蛋白诱导的淋巴细胞凋亡的保护效果，细胞外组蛋白是脓毒症死亡的主要原因。用人血淋巴细胞分别用50μg/ml组蛋白、2μg/ml GSPE或两者组合进行处理。将100μM的N-乙酰半胱氨酸（NAC），一种活性氧（ROS）抑制剂，用作GSPE的阳性对照。检测细胞凋亡、细胞内ROS水平、线粒体膜电位、Bcl-2表达和caspase-3裂解情况。我们的数据清楚地表明，GSPE显著抑制了细胞外组蛋白诱导的淋巴细胞凋亡、ROS生成、线粒体膜电位丧失、Bcl-2表达降低和caspase-3激活。总之，我们表明GSPE对细胞外组蛋白诱导的淋巴细胞凋亡具有保护作用。本研究表明GSPE作为一种潜在的治疗剂，可能有助于减少淋巴细胞凋亡，从而改善脓毒症患者中观察到的免疫抑制状态。
