Zhao-Bin Yang1, Wen-Wen Chen2, Hui-Ping Chen1, Shu-Xian Cai1, Jian-Dong Lin3, Lu-Zhen Qiu4. 1. Medical Intensive Care Unit, Zhangzhou Municipal Hospital of Fujian Province, Zhangzhou 363000, China. 2. Department of Neonatology, Zhangzhou Municipal Hospital of Fujian Province, Zhangzhou 363000, China. 3. Intensive Care Unit, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350001, China. Electronic address: linjiandong386@163.com. 4. Medical Intensive Care Unit, Zhangzhou Municipal Hospital of Fujian Province, Zhangzhou 363000, China. Electronic address: qiuluzhen613@163.com.
Abstract
OBJECTIVE: Liver is uniquely vulnerable during sepsis. MicroRNA-155 (miR-155) is confirmed to play crucial roles in septic liver injury. The present study aims to investigate the mechanisms of miR-155 in septic liver injury. METHODS: The sepsis model was established by intraperitoneal injection of lipopolysaccharide (LPS) in mice. Mice were divided into four groups: Vehicle, miR-155 antagomir, LPS, LPS+ miR-155 antagomir. The survival rate and body weight were monitored. Liver injury was assessed by H&E staining. The levels of serum ALT and inflammatory cytokines were determined by ELISA kits. Oxidative stress was detected by MDA and SOD detection kits. The miR-155, Nrf-2, and markers related to oxidative stress, endoplasmic reticulum (ER) stress, mitochondrial injury and apoptosis were detected by western blotting and qPCR. Apoptosis in liver tissues was detected by TUNELstaining. RESULTS: MiR-155 antagomir alleviated liver injury as evidenced by enhancing survival rate and body weight, inhibiting inflammatory cell infiltration, liver cells necrosis and decreasing ALT level. The productions of TNF-α, IL-6 were suppressed, while anti-inflammatory cytokine IL-10 was promoted by miR-155 antagomir. Oxidative stress was inhibited by miR-155 antagomir via enhancing nuclear factor, erythroid 2-like 2 (Nrf-2) expression. ER stress and Cytochrome C (Cyto-C) release were restrained by miR-155 antagomir. Sepsis-induced apoptosis was repressed by miR-155 antagomir as manifested by the decreased levels of Bax, cleaved caspase-12, 9 and 3, and increased levels of Bcl-2 and uncleaved PARP. CONCLUSION: MiR-155 antagomir relieved septic liver injury through inhibiting oxidative stress-mediated ER stress, mitochondrial dysfunction and apoptosis via targeting Nrf-2, suggesting miR-155 as a therapeutic target for septic liver injury.
OBJECTIVE: Liver is uniquely vulnerable during sepsis. MicroRNA-155 (miR-155) is confirmed to play crucial roles in septic liver injury. The present study aims to investigate the mechanisms of miR-155 in septic liver injury. METHODS: The sepsis model was established by intraperitoneal injection of lipopolysaccharide (LPS) in mice. Mice were divided into four groups: Vehicle, miR-155 antagomir, LPS, LPS+ miR-155 antagomir. The survival rate and body weight were monitored. Liver injury was assessed by H&E staining. The levels of serum ALT and inflammatory cytokines were determined by ELISA kits. Oxidative stress was detected by MDA and SOD detection kits. The miR-155, Nrf-2, and markers related to oxidative stress, endoplasmic reticulum (ER) stress, mitochondrial injury and apoptosis were detected by western blotting and qPCR. Apoptosis in liver tissues was detected by TUNELstaining. RESULTS:MiR-155 antagomir alleviated liver injury as evidenced by enhancing survival rate and body weight, inhibiting inflammatory cell infiltration, liver cells necrosis and decreasing ALT level. The productions of TNF-α, IL-6 were suppressed, while anti-inflammatory cytokine IL-10 was promoted by miR-155 antagomir. Oxidative stress was inhibited by miR-155 antagomir via enhancing nuclear factor, erythroid 2-like 2 (Nrf-2) expression. ER stress and Cytochrome C (Cyto-C) release were restrained by miR-155 antagomir. Sepsis-induced apoptosis was repressed by miR-155 antagomir as manifested by the decreased levels of Bax, cleaved caspase-12, 9 and 3, and increased levels of Bcl-2 and uncleaved PARP. CONCLUSION:MiR-155 antagomir relieved septic liver injury through inhibiting oxidative stress-mediated ER stress, mitochondrial dysfunction and apoptosis via targeting Nrf-2, suggesting miR-155 as a therapeutic target for septic liver injury.