1.Effect and mechanism of cytochrome P450 1A1 on regulating phagocytosis of macrophage
Lixing TIAN ; Linghui WAN ; Junyu ZHU ; Huaping LIANG
Chinese Critical Care Medicine 2023;35(2):158-163
Objective:To explore the effect and mechanism of cytochrome P450 1A1 (CYP1A1) on regulating phagocytosis of macrophage treated with Escherichia coli ( E.coli). Methods:① The mouse leukemia cells lines of monocyte macrophage RAW264.7 (RAW) were cultured in vitro and treated with 30 multiplicity of infection (MOI) dosages of E.coli for 40 minutes, glycerin control group was set up to observe the change of CYP1A1 during infection. ② The RAW cells with CYP1A1 overexpression (CYP1A1/RAW) and knock out (CYP1A1 KO/RAW) were cultured in vitro and treated with 30 MOI E. coli for 40 minutes, while the negative controlled RAW cells (NC/RAW) were established as control to observe the relationship between cell phagocytosis and CYP1A1 expression, and the effect of CYP1A1 on phagocytic receptor [scavenger receptor-A (SR-A)] and its signal pathway [mitogen-activated protein kinase (MAPK) pathway]. ③ NC/RAW and CYP1A1 KO/RAW cells were cultured in vitro and pretreated with 1 μmol/L extracellular signal-regulated kinase (ERK) inhibitor (U0126) for 2 hours, and then treated with 30 MOI E.coli for 40 minutes, phosphate buffered solution (PBS) control group was set up to observe whether the effect of CYP1A1 on phagocytosis through controlled the MAPK pathway. ④ The RAW cells were cultured in vitro and pretreated with 100 nmol/L CYP1A1 hydroxylase active product 12(S)-hydroxyeicosatetraenoic acid [12(S)-HETE] for 2 hours, and then treated with 30 MOI E.coli for 40 minutes, and PBS control group was set up to observe whether the effect of CYP1A1 on phagocytosis was related to CYP1A1 hydroxylating metabolite. ⑤ The RAW cells with overexpression CYP1A1 hydroxylase-activity mutation (CYP1A1m/RAW) were cultured in vitro and treated with 30 MOI E.coli for 40 minutes, the CYP1A1/RAW cells were set up as control group to observe whether the effect of CYP1A1 on phagocytosis was related to CYP1A1 hydroxylase-activity. Results:① Compared with glycerin control group, CYP1A1 mRNA expression was significantly increased by E.coli stimulation (2 -ΔΔCt: 7.79±0.71 vs. 1.00±0.00, P < 0.05), indicating that CYP1A1 might participate in regulating infection progress. ② Compared with NC/RAW cells, the number of E.coli colonies phagocytized by CYP1A1/RAW cells was significantly decreased after 40 minutes of E.coli stimulation (×10 3 CFU/mL: 4.67±3.06 vs. 15.67±5.03, P < 0.05), while CYP1A1 KO/RAW cells had a significant increase in the number of E.coli colonies phagocytized (×10 3 CFU/mL: 46.00±5.29 vs. 15.67±5.03, P < 0.05), suggesting that CYP1A1 might negatively control macrophage phagocytosis function. Meanwhile, compared with NC/RAW cells, the expression of SR-A mRNA in CYP1A1/RAW cells was significantly down-regulated (2 -ΔΔCt: 0.31±0.03 vs. 1.00±0.00, P < 0.05), and the activation level of ERK was significantly reduced. However, the expression of SR-A mRNA in CYP1A1 KO/RAW cells was significantly up-regulated (2 -ΔΔCt: 3.74±0.25 vs. 1.00±0.00, P < 0.05), and the activation of ERK was enhanced, indicating that CYP1A1 could negatively regulate phagocytic receptors and their signaling pathways.③ Compared with PBS, U0126 pretreatment significantly inhibited the CYP1A1 knockout induced upregulation of SR-A mRNA expression (2 -ΔΔCt: 0.62±0.05 vs. 4.38±0.39, P < 0.05) and ERK activation, and inhibited the enhancement of phagocytosis in macrophages induced by CYP1A1 knock out [ E.coli colonies phagocytized by cells (×10 3 CFU/mL): 12.67±1.15 vs. 45.33±4.16, P < 0.05], suggesting that CYP1A1 inhibited macrophage phagocytosis function by regulating ERK activation. ④ Compared with PBS, the phagocytosis of RAW cells pretreated with 12(S)-HETE did not change significantly [ E.coli colonies phagocytized by cells (×10 3 CFU/mL): 17.00±1.00 vs. 16.33±2.52, P > 0.05], suggesting that CYP1A1 might not control phagocytosis function by its hydroxylase-activity metabolism 12(S)-HETE. ⑤ Compared with CYP1A1/RAW cells, there was no significant change in the phagocytic function of CYP1A1m/RAW cells [ E.coli colonies phagocytized by cells (×10 3 CFU/mL): 3.67±1.15 vs. 3.33±0.58, P > 0.05], suggesting that CYP1A1 might not control phagocytosis function by its hydroxylase-activity. Conclusion:CYP1A1 can negatively regulate the phagocytosis of macrophages by inhibiting the activation of ERK and reducing the expression of SR-A, but this regulatory effect is not related to the activity of CYP1A1 hydroxylase and its pro-inflammatory metabolism 12(S)-HETE.
2.Exploration and practice on the "golden course" construction of high altitude military hygiene course in military medical university
Yu WU ; Huaijun TIAN ; Jiaxin XIE ; Simin ZHOU ; Zhifeng ZHONG ; Huaping DONG ; Pei HUANG ; Peng LI
Chinese Journal of Medical Education Research 2023;22(11):1657-1660
High Altitude Military Hygiene is the professional core course of high-altitude medicine, which is significant to the cultivation of military medical talents urgently needed by plateau troops. Under the background of "golden course" construction and army curriculum reform, aiming at the problems such as outdated content of course materials, single teaching mode and insufficient capacity of practical courses, we actively explored the effective path of "golden course" construction, including the renovation of the curriculum-construction concept, the optimization and reorganization of the teaching content, the expansion of case teaching and equipment teaching methods, and the implementation of curriculum ideological and political education and examination reforms. The reform has further improved the learning effect of students and the level of curriculum construction, and also provided beneficial reference for the construction of similar courses in military colleges and universities.
3.Practice and effect analysis of emergency cluster management
Aihui LIU ; Jian TIAN ; Fan LI ; Huaping LIU ; Wenhua ZHOU ; Huadong ZHU ; Jun XU ; Liyuan TIAN
Chinese Journal of Hospital Administration 2021;37(8):686-689
Objective:To analyze the application effect of cluster management measures in improving the quality of emergency medical treatment.Methods:By analyzing the problems existing in the work of emergency department, the cluster management scheme was formulated and the intervention measures were implemented from the aspects of intelligent information system, patient management system and medical service process. The accuracy and efficiency of emergency triage, the satisfaction of patients and medical staff, the incidence of medical complaints and disputes and the rate of sudden death were compared before and after cluster management.Results:Before and after the implementation of cluster management, the accuracy of triage classification was 95.0% and 98.7% respectively, and the triage time was (68.3±12.8) s and (50.5±7.2) s respectively( P<0.001). The satisfaction of patients, doctors and nurses increased, the number of complaints decreased from 15 to 5 in half a year, and the number of sudden death decreased from 39 to 23 with a significant difference( P<0.05). Conclusions:The application of cluster management measures in emergency management can improve the medical quality, the satisfaction of medical staff and patients, and ensure the safety of patients.
4.Early mobilization on mortality of patients with mechanical ventilation in intensive care unit after discharge: a Meta-analysis
Liping YANG ; Zhigang ZHANG ; Caiyun ZHANG ; Wenbo MENG ; Jinhui TIAN ; Xiaojia MA ; Yonghong ZHANG ; Weigang YUE ; Huaping WEI ; Xiping SHEN
Chinese Critical Care Medicine 2021;33(1):100-104
Objective:To evaluate the effect of early mobilization on mortality in intensive care unit (ICU) patients with mechanical ventilation after discharge by Meta-analysis.Methods:Databases including SinoMed, China National Knowledge Infrastructure (CNKI), Wanfang data, PubMed, the Cochrane Library, Web of Science, and Embase were searched from inception to September 17th, 2020, to collect randomized controlled trials (RCT) about early mobilization on mortality of patients with mechanical ventilation in ICU after discharge, the references included in the literature were traced. The control group was given routine care, the experimental group was given early mobilization on the basis of the control group, including passive or active mobilization on the bed, sitting on the bed, standing by the bed, transferring to the bedside chair and assisting walking. The literature screening, data extracting, and the bias risk assessment of included studies were conducted independently by two reviewers. Stata 12.0 software was then used to perform Meta-analysis. Funnel plot was used to test publication bias.Results:A total of 10 RCT studies involving 1 323 patients were included, with 660 patients in the control group and 663 patients in the experimental group. The results of literature quality evaluation showed that 7 studies were grade A and 3 studies were grade B, indicating that the overall quality of included literatures was high. The Meta-analysis results showed that early mobilization did not increase the mortality of patients with mechanical ventilation in ICU after discharge [odds ratio ( OR) = 0.92, 95% confidence interval (95% CI) was 0.75-1.13, P = 0.449]. Subgroup analysis results showed that early mobilization had a tendency to reduce the mortality of ICU patients with mechanical ventilation at 3, 6 and 12 months after discharge, but the difference was not statistically significant (3-month mortality: OR = 1.02, 95% CI was 0.74-1.40, P = 0.927; 6-month mortality: OR = 0.95, 95% CI was 0.70-1.27, P = 0.712; 12-month mortality: OR = 0.60, 95% CI was 0.33-1.10, P = 0.101). Funnel plot showed that the distribution of included literatures was not completely symmetrical, suggesting that publication bias might exist. Conclusions:Early mobilization does not increase the mortality of ICU patients with mechanical ventilation after discharge. Although it tends to have a favorable outcome in reducing mortality, and has a trend to reduce the mortality. However, due to the small number of included literatures, small sample size and differences in the specific implementation of early mobilization among various studies, a large number of high-quality RCT studies are still needed for further verification.
5.Effects of neutrophilic granule protein on nitric oxide production in lipopolysaccharide-induced macrophages
Jing WANG ; Lixing TIAN ; Li TAO ; Chunhong SUN ; Huaping LIANG ; Baigang YAN
Chinese Critical Care Medicine 2021;33(2):198-202
Objective:To explore the influences of neutrophilic granule protein (NGP) on nitric oxide (NO) production in lipopolysaccharide (LPS)-induced macrophages and the regulatory mechanism.Methods:NGP highexpression RAW264.7 cells (NGP/RAW) and negative control empty vector cells (NC/RAW), NGP knockout RAW264.7 cells (NGP KO/RAW) and wild-type cells (WT/RAW) were cultured in vitro. Cells in logarithmic phase were stimulated with 10 mg/L LPS (LPS group) or phosphate buffered saline (PBS group) respectively. The content of NO in the supernatant was detected by Griess method. The mRNA expression of inducible nitric oxide synthase (iNOS) was detected by quantitative reverse transcription-polymerase chain reaction (RT-qPCR). The protein expressions of iNOS and phosphorylated signal transducer and activator of transcription 1 (p-STAT1) were detected by Western blotting.Results:Compared with PBS group, iNOS mRNA and NO expression were significantly increased at different time after LPS stimulation, the mRNA expression of iNOS peaked at 12 hours after LPS stimulation (2 -ΔΔCt: 38.45±1.34 vs. 1.00±0.00 in NC/RAW cells, 56.24±2.41 vs. 1.45±0.30 in NGP/RAW cells, 37.84±1.52 vs. 1.00±0.00 in WT/RAW cells, 5.47±0.62 vs. 0.98±0.40 in NGP KO/RAW cells, all P < 0.05), and the production of NO peaked at 24 hours after LPS stimulation (μmol/L: 24.15±1.26 vs. 0.15±0.04 in NC/RAW cells, 58.80±2.11 vs. 0.18±0.02 in NGP/RAW cells, 25.04±1.80 vs. 0.16±0.02 in WT/RAW cells, 2.42±0.38 vs. 0.12±0.03 in NGP KO/RAW cells, all P < 0.05). After being stimulated by LPS, the expression of iNOS mRNA and NO in NGP/RAW cells were increased significantly compared with NC/RAW cells [iNOS mRNA (2 -ΔΔCt): 8.42±0.59 vs. 4.63±0.37 at 2 hours, 27.16±1.60 vs. 14.25±1.02 at 6 hours, 56.24±2.41 vs. 38.45±1.34 at 12 hours; NO (μmol/L): 4.12±0.25 vs. 2.23±0.17 at 6 hours, 16.50±1.52 vs. 6.35±0.39 at 12 hours, 58.80±2.11 vs. 24.15±1.26 at 24 hours, all P < 0.05]. At the same time, the protein expressions of p-STAT1 and iNOS were also significantly enhanced (p-STAT1/GAPDH: 4.26±1.84 vs. 1.00±0.32 at 0 hours, 20.59±4.97 vs. 0.93±0.21 at 2 hours, 141.99±10.99 vs. 11.17±2.11 at 6 hours; iNOS/GAPDH: 1.27±0.86 vs. 1.00±0.22 at 0 hours, 7.94±1.94 vs. 2.01±0.92 at 2 hours, 24.24±4.88 vs. 3.72±1.11 at 6 hours, all P < 0.05), indicating that NGP might increase the expression of iNOS by promoting the phosphorylation of the signal transducer and activator of transcription 1 (STAT1) pathway, thereby increasing the production of NO. After being stimulated by LPS, the expression of iNOS mRNA and NO in NGP KO/RAW cells were significantly lower than that of WT/RAW cells [iNOS mRNA (2 -ΔΔCt): 2.46±0.31 vs. 4.22±0.18 at 2 hours, 3.61±0.44 vs. 13.02±1.34 at 6 hours, 5.47±0.62 vs. 37.84±1.52 at 12 hours; NO (μmol/L): 1.22±0.19 vs. 2.01±0.12 at 6 hours, 1.60±0.44 vs. 5.15±0.62 at 12 hours, 2.42±0.38 vs. 25.04±1.80 at 24 hours, all P < 0.05]. It showed that iNOS activation was reduced after NGP knockout, which in turn reduced NO production. Conclusion:NGP can positively regulate NO production in activated macrophages by activating the STAT1/iNOS pathway.
6.Evaluation of pharmaceutical prevention and treatment of intensive care unit-acquired weakness: a Meta-analysis
Liping YANG ; Zhigang ZHANG ; Caiyun ZHANG ; Jinhui TIAN ; Xiaojia MA ; Wenbo MENG ; Nannan DING ; Li YAO ; Huaping WEI ; Xiping SHEN
Chinese Critical Care Medicine 2020;32(3):357-361
Objective:To evaluate the effect of preventing and treatment of pharmaceuticals on intensive care unit-acquired weakness (ICU-AW) by systematic review.Methods:The randomized controlled trials (RCTs) concerning pharmaceutical prevention and treatment about ICU-AW in SinoMed, CNKI, Wanfang data, PubMed, Cochrane Library, Web of Science, EMbase, and other sources were searched from their foundation to May 30th, 2019. The patients in the intervention group were treated with drugs to prevent or treat ICU-AW; and those in control group were treated with other rehabilitation methods. Data searching, extracting and quality evaluation were assessed by two reviewers independently. Stata 12.0 software was then used for Meta-analysis. Only descriptive analysis was conducted when only one study was enrolled.Results:A total of 11 RCTs were enrolled with 1 865 patients in the intervention group and 1 894 in the control group. The results of quality evaluation showed that 4 studies were A-level and 7 studies were B-level, indicating that the overall quality of the enrolled literature was high. Meta-analysis showed that intensive insulin therapy could prevent ICU-AW [relative risk ( RR) = 0.761, 95% confidence interval (95% CI) was 0.662-0.876, P = 0.000], but reduced phenylalanine loss (nmol·100 mL -1·min -1: -3±3 vs. -11±3, P < 0.05) and glutamine intake (nmol·100 mL -1·min -1: -97±22 vs. -51±13, P < 0.05). There was no significant difference in the prevention and treatment of ICU-AW between other drugs (including growth hormone, glutamine, dexmedetomidine, neostigmine, oxandrolone, and intravenous immunoglobulin) and control group. Conclusions:Intensive insulin therapy can prevent ICU-AW, but the risk of hypoglycemia will increase. Other drugs including growth hormone, glutamine, dexmedetomidine, neostigmine, oxandrolone, and intravenous immunoglobulin have no obvious advantages in the prevention and treatment of ICU-AW, so no drug has been recommended to prevent and treat ICU-AW.
7.Effects of cytochrome P450 1A1 on nitric oxide production in lipopolysaccharide-induced macrophages
Xin TANG ; Tao CHEN ; Lixing TIAN ; Huaping LIANG
Chinese Critical Care Medicine 2020;32(5):605-610
Objective:To determine the effects of cytochrome P450 1A1 (CYP1A1) on nitric oxide (NO) production in lipopolysaccharide (LPS)-induced macrophages and the underlying mechanism.Methods:The peritoneal macrophages (PMs) were isolated from healthy C57BL/6 mice and stimulated with 10 mg/L LPS to establish inflammatory response model. The CYP1A1 mRNA and protein expressions in the cells were determined. The mouse macrophages RAW264.7 cell line with CYP1A1 overexpression (CYP1A1/RAW) were cultured in vitro, and they were stimulated by 10 mg/L LPS at logarithmic phase. The negative control-expressed RAW264.7 cells (NC/RAW) were established. The protein and mRNA expressions of activator protein-1 (AP-1) and inducible nitric oxide synthase (iNOS) in the cells as well as the content of NO in the cell supernatant were determined. The RAW264.7 cells were cultured in vitro, and they were stimulated by 10 mg/L LPS and 100 nmol/L 12(S)-hydroxyeicosatetraenoic acid [12(S)-HETE] only or in combination at logarithmic phase. The blank control group was set up. The expression of iNOS mRNA in the cells and NO content in the cell supernatant were determined to observe whether the effect of CYP1A1 on LPS induced NO production in macrophages was related to 12(S)-HETE produced by metabolism. The RAW264.7 cells with CYP1A1 overexpression and hydroxylase activity mutation (CYP1A1m/RAW) were cultured in vitro, and they were stimulated by 10 mg/L LPS at logarithmic phase. The CYP1A1/RAW cell control group was set up. The iNOS mRNA expression in the cells and NO content in the cell supernatant were determined to observe the effect of hydroxylase activity of CYP1A1 in regulating NO production in macrophages. Results:Compared with the phosphate buffered saline (PBS) control group, the CYP1A1 mRNA expressions were elevated significantly from 2 hours after LPS stimulation and reached a peak at 12 hours [CYP1A1 mRNA (2 -ΔΔCt): 6.41±0.98 vs. 1.00±0.00, P < 0.05], while CYP1A1 protein expressions were increased from 6 hours after LPS stimulation and reached a peak at 24 hours, suggesting that CYP1A1 expression might be involved in LPS-induced macrophage over-activation. Compared with NC/RAW+LPS group, the iNOS mRNA expressions and NO contents both increased in CYP1A1/RAW+LPS group and reached a peak after 12 hours and 24 hours, respectively [12-hour iNOS mRNA (2 -ΔΔCt): 54.42±8.21 vs. 24.22±3.89, 24-hour NO (μmol/L): 66.52±4.09 vs. 41.42±2.09, both P < 0.05], while the iNOS protein expression and AP-1 phosphorylation also enhanced, suggesting that CYP1A1 might increase NO production by promoting AP-1 activation and iNOS expression. LPS and 12(S)-HETE stimulation only or in combination had no effect on iNOS mRNA expression and NO production, and no significant difference was found between the 12 (S)-HETE+LPS group and LPS group [12-hour iNOS mRNA (2 -ΔΔCt): 34.24±4.07 vs. 34.35±4.01, 24-hour NO (μmol/L): 44.02±3.14 vs. 44.56±3.21, both P > 0.05], suggesting that the regulation of CYP1A1 on NO production might not be induced by 12 (S)-HETE. There was no significant difference in the iNOS mRNA expressions or NO content between the CYP1A1m/RAW+LPS group and CYP1A1/RAW+LPS group [12-hour iNOS mRNA (2 -ΔΔCt): 52.11±6.84 vs. 50.21±5.19, 24-hour NO (μmol/L): 60.42±4.14 vs. 52.01±5.12, both P > 0.05], suggesting that CYP1A1 hydroxylase activity deficiency showed no effect on NO production. Conclusions:LPS stimulation significantly increases CYP1A1 expression in macrophages. CYP1A1 overexpression promotes NO production by activated macrophages through AP-1/iNOS pathway, while hydroxylase-deficiency or 12(S)-HETE has no effect on this regulation.
8. Research progress of 12-HETE in the inflammation and oxidative stress
Qian CHENG ; Lixing TIAN ; Huaping LIANG ; Yan LUO
Chinese Critical Care Medicine 2019;31(12):1555-1558
12-HETE is a metabolite of arachidonic acid (AA). AA is normally present in membrane phospholipids. The exposure to different stimuli can trigger the release of AA through the activity of phospholipase A2 (PLA2) by cells. An important metabolic pathway which utilizes AA as its substrate is 12-Lipoxygenase (12-LOX), resulting in the formation of 12-HETE. 12-HETE plays an important role in many diseases such as cancer, diabetes, hypertension, and participates in the pathogenesis of inflammation and oxidative stress and other pathological processes.Current research shows that it participates in metamorphism and exudation in the process of inflammation. This review is aimed at summarizing its role in inflammation and oxidative stress, with improved understanding of 12-HETE.
9. Regulation of cytochrome P450 1A1 on M2 macrophage polarization
Xiaoyu LI ; Lixing TIAN ; Jing WANG ; Li TAO ; Chunhong SUN ; Huaping LIANG ; Baigang YAN
Chinese Critical Care Medicine 2019;31(11):1340-1344
Objective:
To investigate the potential effects of cytochrome P450 1A1 (CYP1A1) in regulating macrophages polarize to M2 type and explore the molecular mechanism.
Methods:
All trials were completely randomized. ① Experiment 1: 6-8 weeks old healthy male C57BL/6J mice were collected, and primary peritoneal cells were extracted, then the cells were divided into phosphate buffered saline (PBS) group and interleukin-4 (IL-4) group. The cells in the IL-4 group were stimulated with 10 mg/L IL-4 (M2 macrophage inducer); and those in the PBS group were given with an equal amount of PBS. The mRNA expressions of intracellular M2 type polarized marker molecules including arginase-1 (Arg-1) and chitinase 3 like protein 1 (YM1) at 2, 4, 6 hours after IL-4 challenge were determined by quantitative reverse transcription-polymerase chain reaction (RT-qPCR). The phosphorylation of tyrosine protein kinase 1/signaling transcriptional and transduced activator 6 (JAK1/STAT6) signaling pathway and protein expressions of CYP1A1 and Arg-1 at 6, 12, 24 hours after IL-4 challenge were determined by Western Blot. ② Experiment 2: RAW264.7 cells with high expression CYP1A1 (CYP1A1/RAW) and their negative control cells (NC/RAW) were cultured
10. Progress of antimicrobial peptides cathelicidins in infection and immunology
Kuan LIU ; Tao CHEN ; Lixing TIAN ; Jing WANG ; Xin TANG ; Huaping LIANG
Chinese Critical Care Medicine 2019;31(9):1163-1166
Infection is one of the main causes of death in clinical patients, and multi-drug resistance leads to ineffective treatment with conventional antibiotics. Therefore, it is imperative to develop new anti-infective drugs. Antimicrobial peptides cathelicidins are cationic host defense peptides found in many organisms. It has been demonstrated by

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