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@#Objective To explore the relationship between preoperative fasting plasma glucose (FPG) and postoperative pulmonary complications (PPCs) in type 2 diabetic patients undergoing elective thoracoscopic lung resection, and provide a reference for prediction and prevention of PPCs in the clinic. Methods A retrospective analysis was performed on the type 2 diabetic patients who underwent elective thoracoscopic lung resection for the first time in our hospital from January 2017 to March 2021. According to the level of FPG one day before the operation, the patients were divided into three groups: a hypoglycemia group (<6.1 mmol/L), a medium level blood glucose group (≥6.1 mmol/L and <8.0 mmol/L) and a high blood glucose group (≥8.0 mmol/L). Besides, the patients were divided into a PPCs group and a non-PPCs group according to whether PPCs occurred. The risk factors for PPCs were analyzed by logistic regression analysis, and the predictive value of preoperative FPG level on PPCs was estimated by the area under the receiver operating characteristic curve (AUC). Results A total of 130 patients were included, including 75 (57.7%) males and 55 (42.3%) females with an average age of 63.5±9.0 years. Logistic regression analysis showed that compared to non-PPCs patients, the level of preoperative FPG (P=0.023) and smoking history ratio (P=0.036) were higher and the operation time was longer (P=0.004) in the PPCs patients. High FPG level on preoperative day 1 and longer operation time were associated with PPCs risk. Besides, the preoperative FPG of 6.79 mmol/L was the threshold value to predict the occurrence of PPCs [AUC=0.653, 95%CI (0.559, 0.747), P=0.003]. Conclusion There is a certain correlation between preoperative FPG level and postoperative PPCs, which may be used as an index to predict the occurrence of PPCs.
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Objective:To evaluate the role of activation of vesicular glutamate transporter 2 (VGLUT2) neurons in vagal nodose ganglion in dexmedetomidine-caused bradycardia in mice.Methods:Ninety-six SPF healthy male VGLUT2-cre mice, aged 10 weeks, weighing 20-25 g, were divided into 6 groups ( n=16 each) by the random number table method: normal saline control group (NS group), dexmedetomidine group (Dex group), viral control + chemogenetic control + dexmedetomidine group (eGFP-NS+ Dex group), viral transfection + chemogenetic control + dexmedetomidine group (hM4Di-NS+ Dex group), viral control + chemogenetic inhibition + dexmedetomidine group (eGFP-CNO+ Dex group) and viral transfection + chemogenetic inhibition + dexmedetomidine group (hM4Di-CNO+ Dex group). Dexmedetomidine 100 μg/kg was intraperitoneally injected in Dex group. The equal volume of normal saline was intraperitoneally injected in NS group. AAV2/9-hSyn-DIO-hM4Di-eGFP was injected in the right nodose ganglion in hM4Di-NS+ Dex group and hM4Di-CNO+ Dex group, and AAV2/9-hSyn-DIO-eGFP was injected in the right nodose ganglion in eGFP-NS+ Dex group and eGFP-CNO+ Dex group, allowing the virus expression for 21 days. On the 22nd day after virus injection, clozapine-n-oxide (CNO) 5 mg/kg was intraperitoneally injected in hM4Di-CNO+ Dex group and eGFP-CNO+ Dex group, the equal volume of normal saline was intraperitoneally injected in hM4Di-NS+ Dex group and eGFP-NS+ Dex group, 1 h later the efficacy of CNO reached the peak, and then dexmedetomidine 100 μg/kg was intraperitoneally injected. The respiratory rate, heart rate, SpO 2 and discharge frequency of the right vagal nodose ganglion were synchronously measured by multi-channel electrophysiology in vivo. The expression of phosphorylated extracellular signal-regulated kinase (pERK) and VGLUT2 and co-expression of pERK and VGLUT2 in the right vagal nodose ganglion were detected by immunofluorescence assay. Results:Compared with NS group, the percentage of heart rate variation and neuron firing frequency after administration were significantly increased, and pERK expression was up-regulated in the other five groups ( P<0.05). Compared with Dex group, the percentage of heart rate variation and neuron firing frequency after administration were significantly decreased, and pERK expression was down-regulated in hM4Di-CNO+ Dex group, and no significant change was found in the parameters mentioned above in hM4Di-NS+ Dex group, eGFP-NS+ Dex group and eGFP-CNO+ Dex group ( P>0.05). Compared with hM4Di-CNO+ Dex group, the percentage of heart rate variation and neuron firing frequency after administration were significantly increased, and pERK expression was up-regulated in eGFP-CNO+ Dex group ( P<0.05). There was no significant difference in the percentage of respiratory variation and SpO 2 among the six groups ( P>0.05). The expression of VGLUT2-positive neurons was abundant in nodose ganglia, and the co-expression rate of pERK and VGLUT2 was nearly 90%. The co-expression rate of pERK and VGLUT2 decreased to about 30% after inhibition of VGLUT2 neurons in ganglion. Conclusions:The mechanism by which dexmedetomidine causes bradycardia is associated with activation of VGLUT2 neurons in vagal nodose ganglia in mice.
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Objective:To compare the effects of desflurane and sevoflurane anesthesia on the sleep quality of sleep-deprived mice.Methods:Thirty-two clean-grade healthy male C57BL/6 mice, aged 10 weeks, weighing 20-25 g, were divided into 4 groups ( n=8 each) by the random number table method: control group (C group), sleep deprivation group (SD group), sleep deprivation+ sevoflurane group (SD+ SEV group), and sleep deprivation+ desflurane group (SD+ DES group). In the four groups, EEG-EMG electrodes were implanted for recording EEG and EMG, and sleep deprivation model was developed by the gentle stimulation method with a brush for 12 h (6: 00-18: 00) after 7 days of adaptation. The 6 h after sleep deprivation was divided into 2 time periods: T 1 period (18: 00-20: 00) and T 2 period (20: 00-24: 00). T 1 period In SD group, mice were allowed ad libitum recovery sleep after sleep deprivation. C group and SD group were exposed to 60% oxygen 1.5 L/min. In SD+ DES group and SD+ SEV group, mice were exposed to 6% desflurane and 2.5% sevoflurane, respectively, for 2 h in 60% oxygen 1.5 L/min following sleep deprivation. T 2 period Four groups were allowed ad libitum recovery sleep with the EEG-EMG signal recording. The percentages and number of wakefulness time, rapid eye movement time and non-rapid eye movement time during each time period were calculated using Lunion Data software. Results:Compared with C group, the percentage of non-rapid eye movement time and the percentage of rapid eye movement time were significantly decreased, and the percentage of wakefulness time was increased during 12 h sleep deprivation in SD group, SD+ SEV group and SD+ DES group ( P<0.05). Compared with T 1 period, the percentage of non-rapid eye movement time was significantly increased, and the percentage of wakefulness time and percentage of rapid eye movement time were decreased in T 2 period in SD group ( P<0.05). Compared with SD group, the percentage of non-rapid eye movement time and percentage of rapid eye movement time were significantly decreased, and the percentage of wakefulness time was increased in T 2 period in SD+ SEV group and SD+ DES group ( P<0.05). There was no significant difference in the percentage of non-rapid eye movement, rapid eye movement and wakefulness time in T 2 period between SD+ SEV group and SD+ DES group ( P>0.05). Compared with SD+ SEV group, the number of non-rapid eye movement in T 2 period was significantly reduced in SD+ DES group ( P<0.05). Conclusions:The effect of desflurane anesthesia in improving sleep quality is better than sevoflurane anesthesia in sleep-deprived mice.
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Objective:To evaluate the effect of propofol on neuronal activity in medial prefrontal cortex (mPFC) during social behavior in sleep-deprived rats.Methods:Sixty SPF healthy male Sprague-Dawley rats, aged 8 weeks, weighing 200-250 g, were divided into 3 groups ( n=20 each) using a random number table method: control group (group Con), chronic sleep deprivation plus natural sleep group (group CSD+ NS), and chronic sleep deprivation plus propofol group (CSD+ Pro). Sleep deprivation model was developed by the modified multiple platform method, and the rats were placed in the sleep-deprivation tank for 20 h a day (14: 00-10: 00) and allowed to sleep naturally for 4 h (10: 00-14: 00) a day for 28 consecutive days.Propofol 40 mg/kg was intraperitoneally injected after sleep deprivation for 28 consecutive days in group CSD+ Pro, while the equal volume of 10% fat emulsion was given instead in group C and group CSD+ NS.Electroencephalographic recordings in cerebral cortical regions were performed on the days 1st, 14th and 28th after sleep deprivation.The apoptotic neurons in mPFC were detected using TUNEL method after the end of sleep deprivation, and the apoptosis index was calculated.A three chamber sociability test was used to detect the social behavior of rats, and local field potential signals in mPFC were collected. Results:Compared with group Con, the percentage of rapid eye movement sleep was significantly increased, the sniffing time preference coefficients in the 2 stages were reduced, the percentage of the β waves and θ waves-band power in mPFC during the social sniffing process was decreased, and the apoptosis index of neurons in mPFC was increased in group CSD+ NS ( P<0.05). Compared with group CSD+ NS, the percentage of rapid eye movement sleep was significantly increased, the sniffing time preference coefficient in the 2 stages was increased, and the percentage of β waves and θ waves-band power in mPFC during the social sniffing process was increased, and the apoptosis index of neurons in mPFC was decreased in group CSD+ Pro ( P<0.05). Conclusions:Propofol inhibits the apoptosis in neurons in mPFC and increases β and θ waves in the mPFC during social interaction after sleep deprivation in sleep-deprived rats, which is helpful in improving sleep deprivation-induced social disorder.
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Objective:To evaluate the relationship between nuclear factor E2-related factor 2 (Nrf2) and ferroptosis during lung ischemia-reperfusion (I/R) in rats.Methods:Fifty-four healthy male Sprague-Dawley rats, weighing 220-250 g, were divided into 3 groups ( n=18 each) using a random number table method: sham operation group (Sham group), lung I/R group (IR group), and lung I/R+ Nrf2 agonist sulforaphane group (IR+ SFP group). Lung I/R model was developed by clamping the left pulmonary hilum for 60 min followed by 120 min of reperfusion.In IR+ SFP group, SFP 500 μg/kg was intraperitoneally injected at 3 days before lung ischemia once a day for 3 consecutive days, and the model was developed at 2 h after the end of administration.The rats were sacrificed at the end of reperfusion, and the bronchoalveolar lavage fluid (BALF) was collected to determine the protein concentration (using bicinchoninic acid method), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentrations (by enzyme-linked immunosorbent assay). The animals were then sacrificed, and lung tissue specimens were harvested for microscopic examination of the pathological changes (with a transmission electron microscope) and for determination of wet/dry weight (W/D) ratio, contents of iron, malondialdehyde (MDA) and glutathione (GSH) (by chemical colorimetric) and expression of nuclear Nrf2, glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4) (by Western blot). Results:Compared with Sham group, the concentrations of protein, IL-6 and TNF-α in BALF, W/D ratio, and contents of Fe 2+ and MDA were significantly increased, GSH content was decreased, GPX4 expression was down-regulated, the expression of nuclear Nrf2and ACSL4 was up-regulated ( P<0.05), and the mitochondrial morphology of type Ⅱalveolar epithelial cells showed the characteristic changes of ferroptosis, including the presence of smaller mitochondria and reduced cristae in IR group.Compared with IR group, the concentrations of protein, IL-6 and TNF-α in BALF, W/D ratio, and contents of Fe 2+ and MDA were significantly decreased, GSH content was increased, the expression of nuclear Nrf2 and GPX4 expression was up-regulated, ACSL4 expression was down-regulated ( P<0.05), and the pathological changes of lung tissues were significantly attenuated in IR+ SFP group. Conclusions:Nrf2 can inhibit ferroptosis during lung I/R and is involved in the endogenous protective mechanism in rats.
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Objective:To evaluate the role of sonic hedgehog (Shh)/glioma-associated oncogene homolog 1 (Gli1) signaling pathway in sleep deprivation-induced cognitive impairment in young mice.Methods:Forty-eight SPF healthy male C57BL/6 mice, aged 4 weeks, weighing 14-16 g, were divided into 3 groups ( n=16 each) by the random number table method: control group (C group), sleep deprivation group (SD group) and Shh agonist SAG group (SD+ SAG group). Multi-platform water environment method was used to prepare the sleep deprivation model in mice, and the sleep deprivation was 20 h a day for 10 consecutive days.In SD+ SAG group, SAG 10 mg/kg was intraperitoneally injected at 5 min before each sleep deprivation, while the equal volume of normal saline was intraperitoneally injected in group C and group SD.The mice underwent novel object recognition and Y-maze tests at 24 h after development of the model.Mice were sacrificed after the behavioral testing, and the hippocampi were isolated for determination of the density of dendritic spines in hippocampal CA1 region (by Golgi staining), expression of Gli1 and brain-derived neurotrophic factor (BDNF) in hippocampal tissues (by Western blot), and expression of Gli1 and BDNF mRNA in hippocampal tissues (by quantitative real-time polymerase chain reaction). Results:Compared with group C, the preference index in novel object recognition and Y-maze tests and density of dendritic spines in CA1 region were significantly decreased, and the expression of Gli1 and BDNF protein and mRNA in hippocampus was down-regulated in group SD ( P<0.05). Compared with group SD, the preference index in novel object recognition and Y-maze tests and density of dendritic spines in CA1 region were significantly increased, and the expression of Gli1 and BDNF protein and mRNA in hippocampus was up-regulated in group SD+ SAG ( P<0.05). Conclusions:Inhibition of Shh/Gli1 signaling pathway and reduction of plasticity of dendritic spines of hippocampal neurons are involved in sleep deprivation-induced cognitive impairment in young mice.
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Objective:To evaluate the effect of artesunate on intestinal ischemia/reperfusion (I/R)-induced lung injury in mice and relationship with heme oxygenase-1 (HO-1).Methods:Twenty-four healthy SPF male C57BL/6 mice, aged 8-9 weeks, weighing 18-22 g, were divided into 4 groups ( n=6 each) using a random number table method: sham operation group (group Sham), intestinal I/R group (group I/R), artesunate group (group A), and artesunate plus HO-1 inhibitor Zinc protoporphyrin Ⅸ(ZnPP) group (group AS). The model of intestinal I/R injury was established by occluding the superior mesenteric artery for 45 min followed by 2 h reperfusion in anesthetized animals.Artesunate 40 mg/kg was injected via the tail vein at 1 h before ischemia in group A. ZnPP 7.5 mg/kg was injected via the tail vein at 12 h before ischemia, and artesunate 40 mg/kg was injected via the tail vein at 1 h before ischemia in group AS.The animals were sacrificed at the end of reperfusion, and the lung tissues were obtained for microscopic examination of the pathologic changes and for determination of the wet/dry lung weight (W/D) ratio, myeloperoxidase (MPO) activity, malondialdehyde (MDA) content, expression of interleukin-6 (IL-6) mRNA (by fluorescence quantitative polymerase chain reaction) and apoptotic index (AI) (by TUNEL). The lung injury score was assessed. Results:Compared with group Sham, the lung injury score, W/D ratio, MPO activity, MDA content and AI were significantly increased, and the expression of IL-6 mRNA was up-regulated in group I/R ( P<0.05). Compared with group I/R, the lung injury score, W/D ratio, MPO activity, MDA content and AI were significantly decreased, and the expression of IL-6 mRNA was down-regulated in group A ( P<0.05). Compared with group A, the lung injury score, W/D ratio, MPO activity, MDA content and AI were significantly increased, and the expression of IL-6 mRNA was up-regulated in group AS ( P<0.05). Conclusions:Artesunate can alleviate intestinal I/R-induced lung injury, and the mechanism may be related to activation of HO-1 in mice.
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Objective:To evaluate the relationship between thalamocortical glutamate and neuronal activity in mice with neuropathic pain-induced sleep disorders.Methods:SPF healthy male C57BL/6 mice, aged 6-8 weeks, weighing 15-25 g, were divided into 2 groups ( n=14 each) using a random number table method: sham operation group (Sham group) and neuropathic pain group (CCI group). Neuropathic pain was induced by chronic constrictive injury (CCI). The animals were anesthetized with intraperitoneal 10% chloral hydrate 3 ml/kg.The right sciatic nerve was exposed and 4 ligatures were placed on the sciatic nerve at 1 mm intervals.The mechanical paw withdrawal threshold and thermal paw withdrawal latency on the operated side were measured at 1 day before CCI (T 0) and 3, 5, 7, 14 and 21 days after CCI (T 1-5). Electroencephalogram recording electrodes were stereotaxically implanted in visual cortex at T 3, and electroencephalogram were monitored for 6 h, the percentages of non-rapid eye movement, rapid eye movement and wakefulness in the total time were calculated.Microwire electrodes were implanted epidurally over the ventral posterior (VP) nucleus of the thalamus and primary somatosensory cortex (S1) using a brain stereotaxic apparatus at T 3, and the data acquisition system was used to record field potentials at T 4, the percentage of power of each wave was calculated, and the coherence of the field potentials of VP and S1 was simultaneously evaluated.The mice were sacrificed at T 4, brain tissues were collected, and proton nuclear magnetic resonance spectroscopy was used to determine the level of neurotransmitter in the thalamus and cortex. Results:Compared with group Sham, the mechanical paw withdrawal threshold was significantly decreased and thermal paw withdrawal latency was shortened at T 1-5, the percentage of non-rapid eye movement time was decreased, the percentage of wakefulness time was increased, the percentage of δ wave power in the VP area was decreased, the percentage of δ wave power in the VP and S1 areas was increased, and the coherence of the field potentials of VP-S1 was increased in the frequency range of δ wave (1-4 Hz) and α wave (8-14 Hz), and the levels of glutamate, glutamine and glutamate-glutamine in the thalamus and cortex were increased in group CCI ( P<0.05). Conclusions:Neuropathic pain-induced sleep disturbance is related to increased thalamocortical glutamate levels, resulting in changes in the electrical activity of thalamocortical neurons of mice.
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Objective:To evaluate the role of ErbB2 interacting protein (Erbin) in sepsis-associated encephalopathy (SAE) in mice and the relationship with nod-like receptor thermoprotein domain associated protein 3 (NLRP3) inflammasomes.Methods:Sixty SPF-grade healthy male wild-type C57BL/6 mice and 60 Erbin (-/-)C57BL/6 mice, aged 8-10 weeks, weighing 20-25 g, were divided into 4 groups ( n=30 each) by a random number table method: wild-type sham operation group (WT+ Sham group), wild-type SAE group (WT+ SAE group), Erbin (-/-) sham operation group (EKO+ Sham group) and Erbin (-/-) plus SAE group (EKO+ SAE group). The model of SAE was established by cecal ligation and perforation in anesthetized mice.Open field test (total distance moved) was performed at 7 days after establishing the model, new object recognition test (recognition index) was performed at 8 days after establishing the model, and Morris water maze test (time of staying at target quadrant) was performed at 10 days after establishing the model.The mice were sacrificed, and hippocampal tissues were removed for microscopic examination of pathologic changes (by HE staining) and for determination of neuron count, expression of NLRP3, caspase-1 and apoptosis-associated speck-like protein containing a CARD (ASC) (by Western blot), the number of NLRP3 positive cells (by immunohistochemistry), and contents of interleukin-1beta (IL-1β), tumor necrosis factor-alpha (TNF-α) and IL-18 (by enzyme-linked immunosorbent assay). The cell survival rate was calculated. Results:Compared with group WT+ Sham, the time of staying at target quadrant was significantly shortened, the recognition index and cell survival rate were decreased, the contents of IL-1β, IL-18 and TNF-α and the number of NLRP3 positive cells were increased, and the expression of NLRP3, caspase-1 and ASC was up-regulated in group WT+ SAE ( P<0.05). Compared with group EKO+ Sham, the time of staying at target quadrant was significantly shortened, the recognition index and cell survival rate were decreased, the contents of IL-1β, IL-18 and TNF-α and the number of NLRP3 positive cells were increased, and the expression of NLRP3, caspase-1 and ASC was up-regulated in group EKO+ SAE ( P<0.05). Compared with group WT+ SAE, the time of staying at target quadrant was significantly shortened, the recognition index and cell survival rate were decreased, the contents of IL-1β, IL-18 and TNF-α and the number of NLRP3 positive cells were increased, and the expression of NLRP3, caspase-1 and ASC was up-regulated in group EKO+ SAE ( P<0.05). There was no significant difference in total distance moved between the four groups ( P>0.05). Conclusion:Erbin can exert endogenous protection by inhibiting the activation of NLRP3 inflammasomes in mice with SAE.
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Objective:To evaluate the changes in glucose metabolism in the prefrontal cortex during long-term cognitive dysfunction induced by neuropathic pain in developing rats.Methods:SPF healthy male Sprague-Dawley rats, aged 4 weeks, weighing 80-100 g, were used in this study.The model of neuropathic pain was established by using spared nerve injury in anesthetized rats.The mechanical paw withdrawal threshold (MWT) was measured at 1 day before establishing the model (T 0) and 1, 3, 7, 14, 28, 42 and 56 days after establishing the model (T 1-7). According to the results of MWT compared between T 5 and T 0, the rats were divided into neuropathic pain group (group NP) and non-neuropathic pain group (group NNP). Open field test and novel object recognition test were performed at T 7 to assess anxiety-like behavior and cognitive function.Positron emission tomography/computed tomography imaging was performed to determine the standard uptake value of 18F-fluorodeoxyglucose in the prefrontal cortex.Then the rats were sacrificed, and prefrontal cortex was removed for determination of the expression of glucose transporter 3 using Western blot and immunofluorescence. Results:Compared with the baseline at T 0, the MWT at T 1-2 in group NNP and at T 1-7 in group NP were significantly decreased ( P<0.05). Compared with group NNP, the MWT at T 1-7 were significantly decreased, the time of staying at the central region at T 7 was shortened, the percentage of time for exploring the novel object was decreased, the percentage of novel object exploration was decreased, the standard uptake value of 18F-fluorodeoxyglucose in prefrontal cortex was decreased, and the expression of glucose transporter 3 in prefrontal cortex was down-regulated in group NP ( P<0.05). Conclusion:Long-term cognitive dysfunction induced by neuropathic pain may be related to decreased glucose metabolism in the prefrontal cortex of the developing rats.
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Objective:To evaluate the role of cannabinoid type 2 receptor (CB2R) in sevoflurane postconditioning-induced reduction of intestinal ischemia-reperfusion (I/R) injury in rats.Methods:Twenty-four clean-grade healthy male Sprague-Dawley rats, aged 8-10 weeks, weighing 220-270 g, were divided into 4 groups ( n=6 each) using a random number table method: sham operation group (group Sham), intestinal I/R group (group I/R), intestinal I/R+ sevoflurane postconditioning group (group Sevo) and intestinal I/R+ sevoflurane postconditioning+ CB2R antagonist AM630 group (group AM). The model of intestinal I/R injury was established by occluding the superior mesenteric artery for 45 min followed by 2 h reperfusion.In the group Sevo, 2% sevoflurane was inhaled immediately at the beginning of reperfusion for 30 min.In the group AM, CB2R antagonist AM630 3 mg/kg was intraperitoneally injected at 1 h before ischemia, and the other treatments were similar to those previously described in group Sevo.At 2 h of reperfusion, the animals were sacrificed after anesthesia, and small intestinal tissues were obtained for microscopic examination of the pathologic changes which was scored according to Chiu and for determination of wet/dry weight ratio (W/D ratio), for detection of malondialdehyde (MDA) content (by thiobarbituric acid colorimetry), for determination of myeloperoxidase (MPO) activity (by MPO assay) and cleaved caspase-3 protein expression (by Western blot). Results:Compared with group Sham, the Chui score, W/D ratio, MDA content and MPO activity in the intestinal tissues were significantly increased, cleaved caspase-3 expression was up-regulated in group I/R ( P<0.05). Compared with group I/R, the Chui score, W/D ratio, MDA content and MPO activity in the intestinal tissues were significantly decreased, cleaved caspase-3 expression was down-regulated in group Sevo ( P<0.05). Compared with group Sevo, the Chui score, W/D ratio, MDA content and MPO activity were significantly increased, cleaved caspase-3 expression was up-regulated in group AM ( P<0.05). Conclusion:CB2R is involved in the process of sevoflurane postconditioning-induced reduction of intestinal I/R injury in rats.
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Objective:To evaluate the relationship between the mechanism of protective effect of hydromorphone postconditioning on myocardium and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway-mediated autophagy in rats.Methods:Forty healthy male Sprague-Dawley rats, weighing 220-250 g, were divided into 5 groups ( n=8 each) using a random number table method: sham operation group (Sham group), ischemia-reperfusion (I/R) group (group IR), hydromorphone postconditioning group (group HP), PI3K inhibitor group (group W) and hydromorphone postconditioning+ PI3K inhibitor group (group HP+ W). Myocardial ischemia was induced by 30 min occlusion of left anterior descending branch of coronary artery followed by 120 min reperfusion.In group HP, hydromorphone 0.1 mg/kg was injected via femoral vein at 5 min before reperfusion in group HP.In group HP+ W, hydromorphone 0.1 mg/kg and wortmannin (PI3K inhibitor) 15 μg/kg were injected via femoral vein at 5 min before reperfusion.In group W, wortmannin 15 μg/kg was injected via femoral vein at 5 min before reperfusion.At the end of reperfusion, the myocardial infarct size (IS) was determined by TTC staining, the activities of serum lactate dehydrogenase (LDH) was detected by colorimetry, myocardial specimens were collected for microscopic examination of the ultrastructure (with a electron microscope), the expression of phosphorylated Akt (p-Akt) and microtubule-associated protein 1 light chain 3 (LC3) was determined by Western blot and the ratio of LC3-Ⅱ/Ⅰwas calculated. Results:Compared with Sham group, IS and the activities of serum of LDH were significantly increased, p-Akt expression in myocardial tissues was up-regulated, the ratio of LC3-Ⅱ/Ⅰwas increased ( P<0.05), autophagic vacuoles were increased and the damage of ultrastructure of cardiomyocytes was obvious in group IR.Compared with group IR, IS and the activities of serum of LDH were significantly decreased, p-Akt expression in myocardial tissues was up-regulated, the ratio of LC3-Ⅱ/Ⅰwas decreased ( P<0.05), autophagic vacuoles were decreased and the damage of ultrastructure of cardiomyocytes was attenuated in group HR.Compared with group HR, IS and the activities of serum of LDH were significantly increased, p-Akt expression in myocardial tissues was down-regulated, the ratio of LC3-Ⅱ/Ⅰwas increased ( P<0.05), autophagic vacuoles were increased and the damage of ultrastructure of cardiomyocytes was aggravated in group HR+ W. Conclusion:The mechanism of protective effect of hydromorphone postconditioning on myocardium is related to activation of PI3K/Akt signaling pathway and inhibition of autophagy in rats.
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Objective:To evaluate the relationship between the over-expression of endocannabinoid receptor 2 (CB2R) and macrophage pyroptosis in mice.Methods:Bone marrow-derived macrophages of mice were transfected by lentivirus vector and successfully screened out two stable cell lines: lentivirus LV5 negative control cells (LV5-NC) and lentivirus LV5CB2R overexpressing cells (OE). Two cell lines were respectively divided into 3 groups ( n=18 each) using a random number table method: control group (LV5-NC-C group, OE-C group), LPS/ATP group (LV5-NC-LPS/ATP group, OE-LPS/ATP group) and CB2R specific agonist HU308 group (LV5-NC-HU308 group, OE-HU308 group). Cells in group C were commonly cultured.In LPS/ATP group, cells were incubated with LPS at a final concentration of 0.5 μg/ml for 5 h, and then incubated with ATP at the final concentration of 5 mmol/L for 1 h. In group LPS/ATP+ HU308, cells were incubated for 5 h with LPS at the final concentration of 0.5 μg/ml and HU308 at the final concentration of 10 μmol/L and then with ATP at the final concentration of 5 mmol/L for 1 h. The expression of CB2R, nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3), caspase-1, and gasdermin D (GSDMD) mRNA was detected by real-time polymerase chain reaction, the expression of caspase-1 was detected by Western blot, and the concentrations of interleukin-18 (IL-18) and IL-1β in the culture medium were determined by enzyme-linked immunosorbent assay. Results:In each cell line, compared with group C, the expression of NLRP3, caspase-1 and GSDMD was significantly up-regulated, and the concentrations of IL-18 and IL-1β were increased in group LPS/ATP ( P<0.05). Compared with group LPS/ATP, the expression of NLRP3, caspase-1 and GSDMD was significantly down-regulated, the concentrations of IL-18 and IL-lβ were decreased in group HU308 ( P<0.05). There was no significant differences in the indicators mentioned above between group V5-NC-C and group OE-C, between group LV5-NC-LPS/ATP and group OE-LPS/ATP, and between group LV5-NC-HU308 and OE-HU308 ( P>0.05). Conclusion:Over-expression of CB2R gene cannot effectively inhibit the occurrence of macrophage pyroptosis, and only activation of CB2R can inhibit it in mice.
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Objective:To investigate the role of PI3K/Akt signaling pathway in hydromorphone postconditioning on alleviating myocardial ischemia/reperfusion (I/R)-induced apoptosis in rats.Methods:Forty healthy male SD rats were randomly(random number) divided into five groups, with 8 rats in each group:①sham group;②I/R group;③I/R+hydromorphone group (I/R+H group);④I/R+PI3K inhibitor group (I/R+W group); and⑤I/R+hydromorphone+PI3K inhibitor group (I/R+H+W group). The myocardial ischemia/reperfusion injury model was established by ligating the left anterior descending coronary artery for 30 min and reperfusion for 120 min. After the experiment, the area of myocardial infarction was measured by 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining. The amount of serum lactate dehydrogenase (LDH) leakage was estimated by colorimetry . The cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) assay. The protein expressions of p-Akt, Bcl-2 and Bax were detected by Western blot. Comparisons among groups were carried out by analysis of variance (ANOVA).Results:Compared with the sham group, the area of myocardial infarction, serum LDH leakage and cardiomyocyte apoptosis were significantly increased, p-Akt and Bax expression were upregulated, Bcl-2 expression was downregulated in the I/R group ( P<0.05). Compared with the I/R group, the area of myocardial infarction, serum LDH leakage and cardiomyocyte apoptosis were markedly decreased, p-Akt and Bcl-2 expression were upregulated and Bax expression was downregulated in the I/R+H group ( P<0.05). Compared with the I/R+H group, the area of myocardial infarction, serum LDH leakage and cardiomyocyte apoptosis were significantly increased, p-Akt and Bcl-2 expression were downregulated, and Bax expression was upregulated in the I/R+H+W group ( P<0.05). Conclusions:Hydromorphone postconditioning can alleviate cardiomyocyte apoptosis induced by myocardial ischemia/reperfusion, and its protection mechanism may be related to the activation of PI3K/Akt signaling pathway.
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Objective:To evaluate the role of miR-146a in hippocampal inflammatory responses in postoperative cognitive dysfunction (POCD) in mice.Methods:One hundred and sixty clean-grade male C57BL/6 mice, aged 12-16 weeks, weighing 22-28 g, were divided into 5 groups ( n=32 each) using a random number table method: control group (group C), group POCD, miR-146a agomir group (group Ag), miR-146a antagomir group (group At) and negative control group (group NC). The mice were subjected to an intramedullary fixation for tibial fracture under 1.5% isoflurane anesthesia to establish POCD model.At 2 days before operation, miR-146a agomir 0.5 nmol (0.1 nmol/μl) was injected into bilateral hippocampi in group Ag, miR-146a antagomir 2.5 nmol (0.5 nmol/μl) was injected in group At, miR-146a negative control solution 2.5 nmol (0.5 nmol/μl) was given in group NC, and the animals in group C did not receive any treatment.At 1 day before operation and at 1, 3 and 7 days after operation, open-field test was performed to evaluate spontaneous motor activity, and contextual fear conditioning test was performed to evaluate cognitive ability 15 min later.At 1 and 3 days after operation, the animals were sacrificed and hippocampi was removed for determination of expression of CD11b (a marker for activation of microglia) in hippocampal CA1 region by immunofluorescence staining.At 6, 12 and 24 h after operation, the expression of miR-146a was detected by quantitative real-time polymerase chain reaction, the expression of interleukin-1 receptor-associated kinase 1 (IRAK1), tumor necrosis factor receptor-associated factor 6 (TRAF6), nuclear factor kappa B p65 (NF-κB p65) and tumor necrosis factor-alpha (TNF-α) was determined by Western blot and interleukin-1beta (IL-1β) and IL-6 contents were determined by enzyme-linked immunosorbent assay. Results:There was no significant difference in the total exploring distance in the open-field test or percentage of freezing time in tone-fear conditioning test at each time point among the five groups( P>0.05). Compared with group C, the percentage of freezing time in the contextual fear conditioning test was significantly decreased at 1, 3 and 7 days after operation, the expression of CD11b at 1 and 3 days after surgery and expression of miR-146a, IRAK1, TRAF6, NF-κB p65 and TNF-α were up-regulated and the contents of IL-1 β and IL-6 were increased at 6, 12 and 24 h after operation in group POCD ( P<0.05). Compared with group NC, the percentage of freezing time in the contextual fear conditioning test was significantly increased at 1, 3 and 7 days after operation, and the expression of CD11b was down-regulated at 1 and 3 days after surgery, and the expression of miR-146a, IRAK1, TRAF6, NF-κB p65 and TNF-α was up-regulated and IL-1β and IL-6 contents were decreased at 6, 12 and 24 h after operation in group Ag, and the percentage of freezing time in the contextual fear conditioning test was decreased at 1, 3 and 7 days after operation, the expression of CD11b at 1 and 3 days after surgery was up-regulated, the expression of miR-146a was down-regulated and IRAK1, TRAF6, NF-κB p65 expression was up-regulated at 6, 12 and 24 h after operation, TNF-α expression was up-regulated and IL-1β and IL-6 contents were increased at 12 and 24 h after operation in group At ( P<0.05). Conclusion:miR-146a is involved in the process of hippocampal inflammatory responses, and the mechanism may be related to the inhibition of IRAK1-TRAF6-NF-κB signaling pathway in mice.
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Objective:To evaluate the changes in the blood-cerebrospinal fluid barrier in postoperative delirium rats.Methods:One hundred and forty-seven healthy female Sprague-Dawley rats, aged 3 months, weighing 240-300 g, were divided into 3 groups ( n=49 each) using a random number table method: control group (group C), anesthesia group (group A) and postoperative delirium group (group P). Group C received no treatment.Group A received 2-h anesthesia with 1.4% isoflurane.Group S underwent an exploratory laparotomy under 1.4% isoflurane anesthesia.The behaviors of rats in each group were tested at 24 h before surgery and 6, 9 and 24 h after surgery using buried food test, open field test and Y maze test.Sodium fluorescence was injected through the tail vein at 6, 9 and 24 h after surgery.Then the rats were sacrificed, the choroid plexus (CP) was obtained, and cerebrospinal fluid (CSF) of bilateral cerebral ventricles was collected, and the expression of ZO-1, occludin, claudin1, E-cadherin and VE-cadherin in CP was detected using Western blot.FITC-dextran 10, 40 and 70 kDa was injected through the tail vein at 6 h after surgery, and then CSF was collected for determination of the concentrations of NaFI, 10, 40 and 70 kDa fluorescein isothiocyanate labeled dextran (FITC-dextran) in CSF by fluorescence spectrophotometry.CP was obtained to observe the morphology of choroid plexus epithelial cells (CPECs) of bilateral cerebral ventricles with a transmission electron microscope. Results:Compared with group C and group A, the latency to eat food in buried food test was significantly prolonged, the time of staying at the central region was shortened, the percentage of the number of entries into novel arm and percentage of time of staying at novel arm in Y maze test were decreased, the freezing time in open field test was shortened, the expression of ZO-1, occludin and claudin1 in CP was down-regulated, the concentrations of NaFI and 10 kDa and 40 kDa FITC-dextranin CSF were increased ( P<0.05 or 0.01), the CPECs arranged at random and loose, the microvilli of CPECs were absent, the tight junction was blurred, and the gap became wider in group P. Conclusion:The occurrence of postoperative delirium is related to the change in blood-cerebrospinal fluid barrier.
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Objective:To evaluate the role of P2X 7 receptor in microglia in the medial prefrontal cortex (mPFC) in neuropathic pain (NP) and the relationship with autophagy in rats. Methods:Sixty-four healthy SPF male Sprague-Dawley rats, aged 6-8 weeks, weighing 200-250 g, were divided into 4 groups ( n=16 each) using a random number table method: sham operation group (S group), NP group, sham operation+ P2X 7 receptor blocking group (SP group), and NP+ P2X 7 receptor blocking group (NP+ P group). The NP model was established by ligation of the sciatic nerve.Fourteen days later a cannula was placed in the mPFC with a brain stereotactic instrument, P2X 7 receptor blocker A-740003 0.5 μg/0.5 μl was injected into bilateral mPFC for 3 consecutive days starting from the 14th day in SP and NP+ P groups, and DMSO 0.5 μl was injected instead of A-740003 in S and NP groups.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 3, 7 and 10 days after establishing the model and 14, 15 and 16 days after administration.Then the rats were sacrificed, and the mPFC was removed for determination of the expression of P2X 7 receptor and mRNA and autophagy-related proteins Beclin1 and LC3Ⅱ/Ⅰ (by quantitative real-time polymerase chain reaction or by Western blot) and co-expression of P2X 7R and microglia (by immunofluorescence) and the number of autophagosomes in mPFC (with a transmission electron microscope). Results:Compared with group S, MWT was significantly decreased, and TWL was shortened at 3, 7 and 10 days after establishing the model, the expression of P2X 7 receptor and mRNA, Beclin1 and LC3Ⅱ/Ⅰ was up-regulated at 30 min after administration on 16 days after establishing the model, and the number of cells co-expressing P2X 7 receptor and IBA-1 and the number of autophagosomes were increased in NP and NP+ P groups ( P<0.05), and no significant change was found in the indexes mentioned above in group SP ( P>0.05). Compared with group NP, MWT was significantly increased, and TWL was prolonged at 30 min after administration on 14, 15 and 16 days after establishing the model, the expression of P2X 7 receptor and mRNA, Beclin1 and LC3Ⅱ/Ⅰ was down-regulated, and the number of cells co-expressing P2X 7 receptor and Iba-1 and the number of autophagosome were decreased in group NP+ P ( P<0.05). Conclusion:Up-regulation of P2X 7 receptor expression in microglia in mPFC is involved in the process of NP in rats, which is associated with the promotion of autophagy.
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Objective:To evaluate the effect of nicotinamide mononucleotide (NMN) on neurogenesis decline in sleep-deprived infancy rats.Methods:Seventy-eight clean-grade healthy male Sprague-Dawley rats, aged 7 days, weighing 10-15 g, were divided into 3 groups ( n=26 each) using a random number table method: control group (group Con), sleep deprivation group (group SD) and sleep deprivation plus NMN group (group SD+ NMN). Sleep deprivation model was established by gentle stimulation method with a brush (10 h per day) for 14 consecutive days.NMN 500 mg/kg was intraperitoneally injected in group SD+ NMN, while the equal volume of aqua pura was given instead in Con and SD groups.5′-bromo-2′-deoxyuridine (BrdU) 100 mg/kg was intraperitoneally injected immediately after the end of sleep deprivation to label the new-born cells.At 24 h after completion of sleep deprivation, the stem cell pluripotency transcription factor (SOX2) and doublecortin (DCX) positive cells in the hippocampal DG region were counted using immunofluorescence and immunohistochemical methods, and positron emission tomography-computed tomography was used to observe the metabolism of 18F-fluorodeoxyglucose in the hippocampus.At 4 weeks after completion of sleep deprivation, the number of neuronal nuclei antigen (NeuN)/BrdU and glial fibrillary acid protein (GFAP)/BrdU positive cells in hippocampal DG region was recorded using immunofluorescence, and novel object recognition test was performed to evaluate the cognitive function. Results:Compared with group Con, the number of SOX2 and DCX positive cells was significantly reduced, the standard uptake value of glucose in the hippocampus was decreased, the number of NeuN/BrdU and GFAP/BrdU positive cells was reduced, and discrimination index in novel object recognition test was decreased in group SD ( P<0.05). Compared with group SD, the number of SOX2, DCX NeuN/BrdU and GFAP/BrdU positive cells was increased, the standard uptake value of glucose in the hippocampus was increased, and discrimination index in novel object recognition test was increased in group SD+ NMN ( P<0.05). Conclusion:Nicotinamide mononucleotide can promote neurogenesis, thus improving cognitive function, and the mechanism is related to increasing the metabolism of hippocampal glucose in sleep-deprived infancy rats.
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Objective:To investigate the effect of oxycodone hydrochloride injection pretreatment on focal cerebral ischemia-reperfusion injury in rats.Methods:Seventy-two male SD rats weighing 200-250 g were randomly divided into 3 groups( n=24 each group): sham operation group (sham group), focal cerebral I/R group (I/R group), and oxycodone hydrochloride injection group (Oxy group). Focal cerebral I/R was induced by middle cerebral artery occlusion for 2 h followed by reperfusion. In the Oxy group, oxycodone hydrochloride 0.5 mg/kg was injected iv at 5 min before ischemia. While the same volume of saline (1 mL) was injected in the sham group and I/R group. The neurological deficit score (NDS) was assessed at 24 h of reperfusion, the rats were then sacrificed, and their brains were immediately removed for determination of brain water content and the infarct volume, and the histopathological changes were observed after HE staining. The levels of cytokines (TNF-α, IL-1β and IL-10) in the ischemia cortex were quantified by ELISA. MPO activity in the ischemia cortex was assessed. Western blot was used to detect the expression of NF-κB in the ischemia cortex. The data were analyzed using SPSS 20.0 software, multiple-group comparisons were performed using one-way ANOVA, and LSD- t test was used for pairwise comparison between groups. A P<0.05 was considered statistically significant different. Results:Compared with the sham group, NDS, brain water content, relative infarction volume and rate of nerve cell necrosis were significantly increased in the I/R and Oxy groups (all P<0.05). Levels of TNF-α, IL-1β, IL-10, NF-κB and the activities of MPO were increased in the ischemia cortex (all P<0.05). Compared the Oxy group with the I/R group, NDS, brain water content, relative infarction volume and rate of nerve cell necrosis were significantly decreased [(1.7±0.9) vs (2.6±1.1);(79.2±2.4)% vs (84.7±4.2)%; (23.0±5.4)% vs (34.8±6.0)%; (25.2±12.4)% vs (54.8±14.8)%, all P<0.05]. The levels of TNF-α, IL-1β, relative expression of NF-κB, and the activities of MPO were significantly decreased in the ischemia cortex [(4.4±1.2) pg/mg vs (6.5±1.2) pg/mg; (5.4±0.7) pg/mg vs (7.8±0.8) pg/mg; (0.83±0.11) vs (1.23±0.33); (0.27±0.09) U/g vs (0.36±0.14) U/g, all P<0.05] , while the concentration of IL-10 was significantly increased [(20.9±4.5) pg/mg vs (9.2±1.6) pg/mg, t=6.036, P=0.000 1]. Conclusions:Oxycodone hydrochloride can attenuate focal cerebral I/R injury through inhibiting NF-κB activity.
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Objective:To evaluate the role of ErbB2-interacting protein (Erbin) in muramyl dipeptide (MDP)-induced inflammatory responses in the macrophages of mice.Methods:Erbin gene knockout RAW264.7 cell line (Erbin -/ -RAW264.7) was constructed by CRISPR/CAS9 gene-editing technology.RAW264.7 cells were cultured in vitro.Each type of cells was divided into 2 groups ( n=16 each)by a random number table method: RAW264.7 group, RAW264.7 plus MDP group, erbin -/ -RAW264.7 group, and erbin -/ -RAW264.7 plus MDP group.In each MDP group, cells were incubated with 10 μg/ml MDP for 6 h, then immunofluorescence was used to determine the expression of nuclear factor kappa B (NF-κB) p65, and the concentrations of tumor necrosis factor-alpha(TNF-α)and interleukin-6(IL-6)in the culture medium were determined by enzyme-linked immunosorbent assay. Results:Compared with RAW264.7 group, the concentrations of TNF-α and IL-6 in the culture medium were significantly increased( P<0.05), NF-κB p65 moved to the nucleus, and the red fluorescence area was increased in RAW264.7+ MDP group.Compared with RAW264.7+ MDP group and Erbin -/- RAW264.7 group, the concentrations of TNF-α and IL-6 in the culture medium were significantly increased ( P<0.05), NF-κB p65 moved more markedly to the nucleus, and the red fluorescence area was increased in Erbin -/-RAW264.7+ MDP group. Conclusion:Erbin inhibits MDP-induced inflammatory responses in macrophages through inhibiting the activity of NF-κB p65 in mice.