Abstract：
BACKGROUND: Sepsis-associated encephalopathy (SAE) develops in 30-70% of hospitalized patients with sepsis. In intensive care units (ICUs), propofol is often administered to ensure an appropriate level of sedation in mechanically ventilated patients. Ferroptosis is a newly identified mode of cellular death characterized by the peroxidation of membrane lipids and excessive iron. This study was conducted to explore the interplay between propofol, sepsis, and ferroptosis.
METHODS: An acute systemic inflammatory model was constructed via the intraperitoneal administration of lipopolysaccharide (LPS). Nissl and Fluoro-Jade C (FJC) staining were employed to display neuronal damage and degeneration. Western blotting and immunofluorescence (IF) staining of Bax and Bcl-2 were used to confirm the neural apoptosis. QPCR of cytokines and DHE staining were used to indicate neuroinflammation. To validate ferroptosis, we assessed the content of malondialdehyde (MDA), GSH, and tissue iron, accompanied by transcription level of CHAC1, PTGS2 and GPX4. Additionally, we examined the content of acyl-CoA synthetase long-chain family member 4 (ACSL4), xCT (SLC7A11, solute carrier family 7 member 11), and glutathione peroxidase 4 (GPX4). The IF staining of Iba1-labeled microglia and GFAP-marked astrocytes were used to measure the gliosis. Erastin was pre-pretreated to confirm the anti-ferroptotic capability of propofol. ML385 was preconditioned to explore the role of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in propofol-repressed ferroptosis.
RESULTS: Propofol dose-dependently inhibited the decrease of Nissl-positive neurons and the increase of FJC-stained neurons in septic hippocampus and cortex. Neural cytokines, oxidative stress, apoptosis and gliosis were reduced by propofol. Propofol repressed the level of MDA, iron, CHAC1, PTGS2, ACLS4 and restored the content of GSH, GPX4, xCT, Nrf2 and HO-1, thus inhibiting sepsis-induced ferroptosis. All protections from propofol could be reversed by eratsin and ML385 pretreatment.
CONCLUSIONS: Propofol protected against sepsis-induced brain damage, neuroinflammation, neuronal apoptosis and gliosis through the activation of the Nrf2/HO-1 axis to combat ferroptosis.
METHODS: An acute systemic inflammatory model was constructed via the intraperitoneal administration of lipopolysaccharide (LPS). Nissl and Fluoro-Jade C (FJC) staining were employed to display neuronal damage and degeneration. Western blotting and immunofluorescence (IF) staining of Bax and Bcl-2 were used to confirm the neural apoptosis. QPCR of cytokines and DHE staining were used to indicate neuroinflammation. To validate ferroptosis, we assessed the content of malondialdehyde (MDA), GSH, and tissue iron, accompanied by transcription level of CHAC1, PTGS2 and GPX4. Additionally, we examined the content of acyl-CoA synthetase long-chain family member 4 (ACSL4), xCT (SLC7A11, solute carrier family 7 member 11), and glutathione peroxidase 4 (GPX4). The IF staining of Iba1-labeled microglia and GFAP-marked astrocytes were used to measure the gliosis. Erastin was pre-pretreated to confirm the anti-ferroptotic capability of propofol. ML385 was preconditioned to explore the role of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in propofol-repressed ferroptosis.
RESULTS: Propofol dose-dependently inhibited the decrease of Nissl-positive neurons and the increase of FJC-stained neurons in septic hippocampus and cortex. Neural cytokines, oxidative stress, apoptosis and gliosis were reduced by propofol. Propofol repressed the level of MDA, iron, CHAC1, PTGS2, ACLS4 and restored the content of GSH, GPX4, xCT, Nrf2 and HO-1, thus inhibiting sepsis-induced ferroptosis. All protections from propofol could be reversed by eratsin and ML385 pretreatment.
CONCLUSIONS: Propofol protected against sepsis-induced brain damage, neuroinflammation, neuronal apoptosis and gliosis through the activation of the Nrf2/HO-1 axis to combat ferroptosis.
摘要：
背景：脓毒症相关脑病（SAE）发生在30-70%的住院脓毒症患者中。在重症监护病房（ICU），通常施用异丙酚以确保机械通气患者的适当镇静水平。铁凋亡是一种新发现的细胞死亡模式，其特征在于膜脂质的过氧化和过量的铁。这项研究是为了探索异丙酚之间的相互作用，脓毒症,和铁中毒。
方法：通过腹腔注射脂多糖（LPS）构建急性全身炎症模型。Nissl和Fluoro-JadeC（FJC）染色用于显示神经元损伤和变性。免疫印迹和Bax和Bcl-2的免疫荧光（IF）染色用于确认神经细胞凋亡。细胞因子的QPCR和DHE染色用于指示神经炎症。为了验证铁沉积，我们评估了丙二醛（MDA）的含量，GSH,和组织铁，伴随着CHAC1、PTGS2和GPX4的转录水平。此外,我们检查了酰基辅酶A合成酶长链家族成员4（ACSL4）的含量，xCT（SLC7A11，溶质载体家族7成员11），和谷胱甘肽过氧化物酶4(GPX4)。Iba1标记的小胶质细胞和GFAP标记的星形胶质细胞的IF染色用于测量神经胶质增生。预先预处理Erastin以确认丙泊酚的抗铁能力。对ML385进行了预处理，以探讨核因子红细胞2相关因子2（Nrf2）和血红素加氧酶-1（HO-1）在异丙酚抑制的铁细胞凋亡中的作用。
结果：丙泊酚剂量依赖性地抑制败血症海马和皮质中Nissl阳性神经元的减少和FJC染色神经元的增加。神经细胞因子，氧化应激，异丙酚减少了细胞凋亡和胶质增生。丙泊酚抑制MDA水平，铁,CHAC1、PTGS2、ACLS4和恢复了GSH的含量，GPX4、xCT、Nrf2和HO-1，从而抑制脓毒症诱导的铁凋亡。异丙酚的所有保护都可以通过eratsin和ML385预处理逆转。
结论：丙泊酚可预防脓毒症引起的脑损伤，神经炎症，神经元凋亡和神经胶质增生通过激活Nrf2/HO-1轴来对抗铁性凋亡。
方法：通过腹腔注射脂多糖（LPS）构建急性全身炎症模型。Nissl和Fluoro-JadeC（FJC）染色用于显示神经元损伤和变性。免疫印迹和Bax和Bcl-2的免疫荧光（IF）染色用于确认神经细胞凋亡。细胞因子的QPCR和DHE染色用于指示神经炎症。为了验证铁沉积，我们评估了丙二醛（MDA）的含量，GSH,和组织铁，伴随着CHAC1、PTGS2和GPX4的转录水平。此外,我们检查了酰基辅酶A合成酶长链家族成员4（ACSL4）的含量，xCT（SLC7A11，溶质载体家族7成员11），和谷胱甘肽过氧化物酶4(GPX4)。Iba1标记的小胶质细胞和GFAP标记的星形胶质细胞的IF染色用于测量神经胶质增生。预先预处理Erastin以确认丙泊酚的抗铁能力。对ML385进行了预处理，以探讨核因子红细胞2相关因子2（Nrf2）和血红素加氧酶-1（HO-1）在异丙酚抑制的铁细胞凋亡中的作用。
结果：丙泊酚剂量依赖性地抑制败血症海马和皮质中Nissl阳性神经元的减少和FJC染色神经元的增加。神经细胞因子，氧化应激，异丙酚减少了细胞凋亡和胶质增生。丙泊酚抑制MDA水平，铁,CHAC1、PTGS2、ACLS4和恢复了GSH的含量，GPX4、xCT、Nrf2和HO-1，从而抑制脓毒症诱导的铁凋亡。异丙酚的所有保护都可以通过eratsin和ML385预处理逆转。
结论：丙泊酚可预防脓毒症引起的脑损伤，神经炎症，神经元凋亡和神经胶质增生通过激活Nrf2/HO-1轴来对抗铁性凋亡。
