Icariin mitigates anxiety-like behaviors induced by hemorrhagic shock and resuscitation via inhibiting of astrocytic activation.

BACKGROUND: Abnormal activation of astrocytes in the amygdala contributes to anxiety after hemorrhagic shock and resuscitation (HSR). Nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB)-associated epigenetic reprogramming of astrocytic activation is crucial to anxiety. A bioactive monomer derived from Epimedium icariin (ICA) has been reported to modulate NF-κB signaling and astrocytic activation. PURPOSE: The present study aimed to investigate the effects of ICA on post-HSR anxiety disorders and its potential mechanism of action. METHODS: We first induced HSR in mice through a bleeding and re-transfusion model and selectively inhibited and activated astrocytes in the amygdala using chemogenetics. Then, ICA (40 mg/kg) was administered by oral gavage once daily for 21 days. Behavioral, electrophysiological, and pathological changes were assessed after HSR using the light-dark transition test, elevated plus maze, recording of local field potential (LFP), and immunofluorescence assays. RESULTS: Exposure to HSR reduced the duration of the light chamber and attenuated open-arm entries. Moreover, HSR exposure increased the theta oscillation power in the amygdala and upregulated NF-κB p65, H3K27ac, and H3K4me3 expression. Contrarily, chemogenetic inhibition of astrocytes significantly reversed these changes. Chemogenetic inhibition in astrocytes was simulated by ICA, but chemogenetic activation of astrocytes blocked the neuroprotective effects of ICA. CONCLUSION: ICA mitigated anxiety-like behaviors induced by HSR in mice via inhibiting astrocytic activation, which is possibly associated with NF-κB-induced epigenetic reprogramming.

Hemorrhagic Shock and Resuscitation Causes Excessive Dopaminergic Signaling in the mPFC and Cognitive Dysfunction.

Peri-operative hemorrhagic shock and resuscitation (HSR), a severe traumatic stress, is closely associated with post-operative anxiety, depression, and cognitive dysfunction, subsequently causing a serious burden on families and society. Following the co-release of corticotropin-releasing factor and catecholamine, traumatic stress activates dopaminergic neurons, increasing the addictive behavior and neurocognitive impairment risks. This study investigates the association between cognitive dysfunction and dopaminergic neurons in the mPFC under HSR conditions. This study established an HSR model by bleeding and re-transfusion in the mice. After HSR exposure, a dopamine D1 receptor antagonist, SKF-83566, was administered intraperitoneally for three consecutive days. Novel object recognition (NOR), conditioned fearing (FC), and conditioned place preference (CPP) were used to assess cognitive changes 16 days after HSR exposure. Local field potential (LFP) in the mPFC was also investigated during the novel object exploration. Compared with the mice exposed to sham, there was a significant decrease in the object recognition index, a reduction in context- and tone-related freezing time, an increase in CPP values, a downregulation of ß-power but upregulation of γ-power in the mPFC in the mice exposed to HSR. Moreover, the mice exposed to HSR showed significantly upregulated TH-positive cell number, cleaved caspase-1- and TH-positive cells, and interleukin (IL)-1ß/18 expression in the mPFC compared with sham; SKF-83566 could partially reverse these alternations. The HSR caused excessive dopaminergic signaling and cognitive dysfunction in the mPFC, a condition that might be ameliorated using a dopamine D1 receptor inhibitor.

[Application of self-made fine-tuning device in distal locking process of femoral interlocking intramedullary nail].

OBJECTIVE: To evaluate the curative efficacy of self-made fine-tuning setting in the process of femoral distal implantation of intramedullary nail. METHODS: From October 2015 to October 2017, 66 cases of femoral shaft fracture were treated with anterograde interlocking intramedullary nail including 45 males and 21 females with a mean age of(37.21±11.18) years old. Among them, 36 cases were treated with the manufacture's aiming device and self-made fine-tuning setting (research group), other 30 cases were treated with the manufacture's aiming device(control group). The mean operation time, the times of C-arm scan in surgery, the post-operation complications and the fracture union were observed and compared in two groups. RESULTS: Sixty-two cases acquired 8 to 15 months with a mean time of 12.4 months follow-up visit. The post-operation complications and the fracture union between the two groups had no significant difference(P>0.05), the mean operation time and the times of C-arm scan in surgery had statistically significant difference(P<0.05). CONCLUSIONS: Self-made fine-tuning setting in the process of femoral interblocking intramedullary nail could shorten operation time and reduce the the times of C-arm scan.