Ping An1, Xiao-Chun Zhao2, Man-Jia Liu3, Yu-Qing You4, Jing-Ya Li5. 1. Department of Neurobiology, School of Life Science, China Medical University, Shenyang, People's Republic of China. Electronic address: anpinglinda@yahoo.com. 2. Department of Anesthesiology, School and Hospital of Stomatology, China Medical University, Shenyang, People's Republic of China. Electronic address: xczhao@cmu.edu.cn. 3. Department of Anesthesiology, ShengJing Hospital of China Medical University, Shenyang, People's Republic of China. Electronic address: lmj_cmu@163.com. 4. Department of Anesthesiology, ShengJing Hospital of China Medical University, Shenyang, People's Republic of China. Electronic address: yq626412107@163.com. 5. Department of Anesthesiology, ShengJing Hospital of China Medical University, Shenyang, People's Republic of China. Electronic address: yingziqiu1130@163.com.
Abstract
BACKGROUND: Post-stroke depression (PSD) severely affects recovery in patients with intracerebral hemorrhage (ICH). Although hydrogen gas (H2) exerts excellent neuroprotective effects in patients with ICH, there are sex-based differences in H2 efficacy in several diseases. Herein, we determined whether estrogen increases susceptibility to the neuroprotective effects of H2 in males with ICH-induced depression. METHODS: A rodent model of ICH in the basal ganglia was established using autologous blood injection (30 μL). Mice were treated with 2.9% H2 for 2 h daily for 3 days post-ICH. Estrogen (1 mg/kg) was administered by subcutaneous injection daily for 3 days to male mice post-ICH. Thirty days post-ICH, PSD was evaluated by sucrose preference, forced swimming, and 3-chamber social tests. Following the completion of behavioral tests, levels of superoxide dismutase (SOD) and reactive oxygen species (ROS), astrocytic activation, phosphorylated (p)-NF-κB-positive astrocytes, p-NF-κB, p-IKKβ, IL-1β, and IL-6 expression were determined. RESULTS: Compared with female mice, H2 administration post-ICH exhibited fewer neuroprotective effects, including decreased sucrose consumption and time spent sniffing a novel mouse, increased immobility time, downregulated total SOD content, upregulated ROS content and p-NF-κB levels, and elevated astrocyte branches, whereas estrogen enhanced the neuroprotective effects of H2 in male mice. A reduced number of p-NF-κB-positive astrocytes, downregulated expression of p-NF-κB, p-IKKβ, IL-1β, and IL-6 in the amygdala were demonstrated in ICH-males treated with estrogen plus H2. CONCLUSIONS: Estrogen was responsible for increased H2 sensitivity in male mice with ICH. The underlying mechanism may be associated with the suppression of NF-κB signaling in astrocytes.
BACKGROUND: Post-stroke depression (PSD) severely affects recovery in patients with intracerebral hemorrhage (ICH). Although hydrogen gas (H2) exerts excellent neuroprotective effects in patients with ICH, there are sex-based differences in H2 efficacy in several diseases. Herein, we determined whether estrogen increases susceptibility to the neuroprotective effects of H2 in males with ICH-induced depression. METHODS: A rodent model of ICH in the basal ganglia was established using autologous blood injection (30 μL). Mice were treated with 2.9% H2 for 2 h daily for 3 days post-ICH. Estrogen (1 mg/kg) was administered by subcutaneous injection daily for 3 days to male mice post-ICH. Thirty days post-ICH, PSD was evaluated by sucrose preference, forced swimming, and 3-chamber social tests. Following the completion of behavioral tests, levels of superoxide dismutase (SOD) and reactive oxygen species (ROS), astrocytic activation, phosphorylated (p)-NF-κB-positive astrocytes, p-NF-κB, p-IKKβ, IL-1β, and IL-6 expression were determined. RESULTS: Compared with female mice, H2 administration post-ICH exhibited fewer neuroprotective effects, including decreased sucrose consumption and time spent sniffing a novel mouse, increased immobility time, downregulated total SOD content, upregulated ROS content and p-NF-κB levels, and elevated astrocyte branches, whereas estrogen enhanced the neuroprotective effects of H2 in male mice. A reduced number of p-NF-κB-positive astrocytes, downregulated expression of p-NF-κB, p-IKKβ, IL-1β, and IL-6 in the amygdala were demonstrated in ICH-males treated with estrogen plus H2. CONCLUSIONS: Estrogen was responsible for increased H2 sensitivity in male mice with ICH. The underlying mechanism may be associated with the suppression of NF-κB signaling in astrocytes.