Electroacupuncture attenuates surgical pain-induced delirium-like behavior in mice via remodeling gut microbiota and dendritic spine.

Surgical pain is associated with delirium in patients, and acupuncture can treat pain. However, whether electroacupuncture can attenuate the surgical pain-associated delirium via the gut-brain axis remains unknown. Leveraging a mouse model of foot incision-induced surgical pain and delirium-like behavior, we found that electroacupuncture stimulation at specific acupoints (e.g., DU20+KI1) attenuated both surgical pain and delirium-like behavior in mice. Mechanistically, mice with incision-induced surgical pain and delirium-like behavior showed gut microbiota imbalance, microglia activation in the spinal cord, somatosensory cortex, and hippocampus, as well as an enhanced dendritic spine elimination in cortex revealed by two-photon imaging. The electroacupuncture regimen that alleviated surgical pain and delirium-like behavior in mice also effectively restored the gut microbiota balance, prevented the microglia activation, and reversed the dendritic spine elimination. These data demonstrated a potentially important gut-brain interactive mechanism underlying the surgical pain-induced delirium in mice. Pending further studies, these findings revealed a possible therapeutic approach in preventing and/or treating postoperative delirium by using perioperative electroacupuncture stimulation in patients.

Urinary Catheterization Induces Delirium-Like Behavior Through Glucose Metabolism Impairment in Mice.

BACKGROUND: Delirium, an acute confusion status, is associated with adverse effects, including the development of Alzheimer's disease. However, the etiology and underlying mechanisms of delirium remain largely to be determined. Many patients have urinary catheterization (UC), and UC is associated with delirium. However, the cause effects of UC-associated delirium and the underlying mechanisms remain largely unknown. We, therefore, established an animal model of UC, without urinary tract infection, in mice and determined whether UC could induce delirium-like behavior in the mice and the underlying mechanism of these effects. METHODS: Adult female mice (16 weeks old) had UC placement under brief isoflurane anesthesia. The delirium-like behavior was determined using our established mice model at 3, 6, 9, and 24 hours after UC placement. We measured the amounts of glucose in both blood and brain interstitial fluid, adenosine triphosphate (ATP) concentration in the cortex, and glucose transporter 1 in the cortex of mice using western blot, immunohistochemistry imaging, reverse transcriptase-polymerase chain reaction (RT-PCR), and fluorescence at 6 hours after the UC placement. Finally, we used vascular endothelial growth factor (VEGF) in the interaction studies. RESULTS: We found that UC induced delirium-like behavior in mice at 3, 6, 9, but not 24 hours after the UC placement. UC decreased glucose amounts in brain interstitial fluid (86.38% ± 4.99% vs 100% ± 6.26%, P = .003), but not blood of mice and reduced ATP amounts (84.49% ± 8.85% vs 100% ± 10.64%, P = .031) in the cortex of mice. Finally, UC reduced both protein amount (85.49% ± 6.83% vs 100% ± 11.93%, P = .040) and messenger ribonucleic acid (mRNA) expression (41.95% ± 6.48% vs 100% ± 19.80%, P = .017) of glucose transporter 1 in the cortex of mice. VEGF attenuated these UC-induced changes. CONCLUSIONS: These data demonstrated that UC decreased brain glucose and energy amounts via impairing the glucose transport from blood to brain, leading to delirium-like behavior in mice. These findings will promote more research to identify the etiologies and underlying mechanisms of delirium.

Acidic Preconditioning Protects Against Ischemia-Reperfusion Lung Injury Via Inhibiting the Expression of Matrix Metalloproteinase 9.

BACKGROUND: Acidic preconditioning (APC) has been demonstrated to protect against ischemia-reperfusion (IR)-induced lung injury, which could occur during lung transplantation or cardiopulmonary bypass. However, the pathophysiological mechanisms underlying IR lung injury and APC protection are not completely understood. The key factors responsible for the protective effects of APC are not clear. In this study, bioinformatics was used to predict the potential key factor in IR lung injury and explore the important mediator of the APC protective effect in IR lung injury. METHODS: First, we screened GSE6730, which is related to both lung injury and IR in Gene Expression Omnibus, and STRING was used later to select the genes in GSE6730 needed in the future. Animal models were established and classified to validate the effect of matrix metalloproteinase 9 (MMP-9) on lung injury after IR by adding a selective inhibitor (4-phenoxyphenylsulfonyl) methylthiirane, MMP-9 inhibitor. Next, for better understanding of APC inhibition of the expression of MMP-9 in lung injury, assessment of lung tissues, Western blot analysis, and RNA extraction and reverse transcription quantitative polymerase chain reaction were conducted. RESULTS: MMP-9 was identified to be overexpressed after IR according to the analysis on GSE67370. MMP-9 was an unknown gene in relation to acute lung injury and found to be associated with interleukin (IL)-1B, IL-6, and IL-8. The expressions of these inflammatory factors, including MMP-9, were all elevated in IR. Furthermore, lung injury was ameliorated, and the level of MMP-9 was lower when an MMP-9 inhibitor, (4-phenoxyphenylsulfonyl) methylthiirane, was added. Compared with group IR, APC reversed the ischemia-induced lung injury, and the level of MMP-9 was lower, and the concentrations of IL-1ß, IL-6, and IL-8 were decreased. CONCLUSIONS: Our findings reveal a novel mechanism indicating that IR induces higher expression of MMP-9 in lung injury by increasing the expression of inflammation-related factors. APC might protect against IR lung injury by inhibiting the expression of MMP-9.

[Low-intensity pulsed ultrasound pretreatment inhibits HMGB1 expression and attenuates lung ischemia-reperfusion injury in rats via the cholinergic anti-inflammatory pathway].

OBJECTIVE: To observe the effects of low-intensity pulsed ultrasound (LIPUS) pretreatment on pulmonary expression of high mobility group box-1 (HMGB1) in a rat model of lung ischemia-reperfusion (IR). METHODS: Thirty-two male SpragueDawley rats weighing 250-300 g were randomly divided (n=8) into sham-operated group, lung IR group, LIPUS pretreatment group and pretreatment with α7-nicotinic cholinergic receptor (α7nAChR) antagonist group. In the sham-operated group, the left pulmonary hilum was dissociated without occlusion; in the other 3 groups, the left pulmonary hilum was occluded for 45 min followed by reperfusion for 180 min; LIPUS pretreatment for 30 min and intraperitoneal injection of methyllycaconitine (2 mg/kg), an α7nAChR antagonist, were administered before the operation. The wet/dry weight ratio (W/D) and pulmonary permeability index (LPI) of the lung tissue were measured, and the lung histopathology was observed and scored. The contents of interleukin-1 (IL-1) and IL-6 in the lung tissues were measured using ELISA, and the pulmonary expression of HMGB1 protein was detected using immunofluorescence assay and Western blotting. RESULTS: Compared with those in the sham-operated group, the W/D of the lung tissue, LPI, pathological scores, IL-1 and IL-6 contents in the lung tissue, and pulmonary HMGB1 expression all significantly increased in the other 3 groups (P < 0.05). LIPUS preconditioning significantly lowered the W/D values, LPI, pathological score, IL-1 and IL-6 contents and HMGB1 expression in the lung tissues following lung IR, and these effects were significantly inhibited by administration of methyllycaconitine. CONCLUSIONS: LIPUS preconditioning can reduce lung IR injury possibly by activating α7nAChR-dependent cholinergic anti-inflammatory pathway to reduce lung tissue HMGB1 expression.

[Effects of acidification pretreatment for respiratory acidosis on the expression of matrix metalloproteinase-9 in rat lung tissues following ischemia/reperfusion].

OBJECTIVE: To establish rat model of lung ischemia/reperfusion (IR) in vivo, and to explore the effects of acidification pretreatment for respiratory acidosis on the expression of matrix metalloproteinase-9 (MMP-9) and the possible mechanisms.
 Methods: A total of 36 male Sprague-Dawley rats were divided into a sham group (S group), a IR group, and an experiment group (RA group) (n=12 in each group). The rat left lung hilum in the S group was dissociated, followed by perfusion without ischemia. After the left lung hilum in the IR group was blocked for 45 min, the rats were followed by reperfusion for 180 min. After left lung hilum in the RA group was dissociated, the respiratory parameters were adjusted so that pressure of end tidal carbon dioxide (PETCO2) reached 56-65 mmHg (1 mmHg=0.133 kPa) for 5 min, then the rats was subjected to IR. Lung tissue wet/dry (W/D) and lung permeability index (LPI) were calculated, while the lung histopathology was observed and the MMP-9 protein expression were measured.
 Results: Compared with the control group, the W/D and LPI in the IR group and the RA group increased after reperfusion (both P<0.05), and the levels of W/D and LPI in the group RA were lower than that in the IR group (P<0.05). LPI and pathology scores were significantly lower in the RA group than those in the IR group (both P<0.01). After IR, the expression of MMP9 in the lung tissues in the IR group and the RA group increased significantly (both P<0.01). The expression of MMP-9 protein in the RA group was significantly lower than that in the IR group (P<0.01).
 Conclusion: After lung IR injury, the expression of MMP-9 protein, vascular permeability and inflammatory exudation is increased. The acidification pretreatment for respiratory acidosis can inhibit the expression of MMP-9 protein and reduce inflammatory exudation after lung IR, showing a protective effect on lung IR injury.

miR-5195-3p Inhibits Proliferation and Invasion of Human Bladder Cancer Cells by Directly Targeting Oncogene KLF5.

miRNAs play a key role in the carcinogenesis of many cancers, including bladder cancer. In the current study, the role of miR-5195-3p, a quite recently discovered and poorly studied miRNA, in the proliferation and invasion of human bladder cancer cells was investigated. Our data displayed that, compared with healthy volunteers (control) and SU-HUC-1 normal human bladder epithelial cells, miR-5195-3p was sharply downregulated in bladder cancer patients and five human bladder cancer cell lines. The oligo miR-5195-3p mimic or miR-5195-3p antagomir was subsequently transfected into both T24 and BIU-87 bladder cancer cell lines. The miR-5195-3p mimic robustly increased the miR-5195-3p expression level and distinctly reduced the proliferation and invasion of T24 and BIU-87 cells. In contrast, the miR-5195-3p antagomir had an opposite effect on miR-5195-3p expression, cell proliferation, and invasion. Our data from bioinformatic and luciferase reporter gene assays identified that miR-5195-3p targeted the mRNA 3'-UTR of Krüppel-like factor 5 (KLF5), which is a proven proto-oncogene in bladder cancer. miR-5195-3p sharply reduced KLF5 expression and suppressed the expression or activation of its several downstream genes that are kinases improving cell survival or promoting cell cycle regulators, including ERK1/2, VEGFA, and cyclin D1. In conclusion, miR-5195-3p suppressed proliferation and invasion of human bladder cancer cells via suppression of KLF5.