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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.
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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.
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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.
ABSTRACT
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.
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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 in vitro. The cells in logarithmic growth phase were collected, and then they were divided into PBS control group and IL-4 group. The treatment method was the same as experiment 1. The phosphorylations of intracellular JAK1/STAT6 and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathways in different cells at 1 hour and 2 hours after IL-4 challenge were determined by Western Blot. The mRNA and protein expressions of Arg-1 in different cells at 2 hours and 4 hours after IL-4 challenge were determined by RT-qPCR and Western Blot, respectively. Results ① Experiment 1: after IL-4 challenge for 2 hours, the mRNA expressions of Arg-1 and YM1 in the primary peritoneal macrophages of mice were significantly increased as compared with the PBS control group [Arg-1 mRNA (2-ΔΔCt): 1.75±0.82 vs. 1.00±0.21; YM1 mRNA (2-ΔΔCt): 2.58±0.53 vs. 1.00±0.20, both P < 0.05] which indicated that IL-4 induced macrophage to M2 type polarization successfully. Meanwhile, the mRNA expression of CYP1A1 in polarized mouse peritoneal primary macrophages was also elevated as compared with the PBS control group, and peaked at 4 hours [CYP1A1 mRNA (2-ΔΔCt): 2.25±0.69 vs. 1.00±0.17, P < 0.01]. The results indicated that CYP1A1 expression was enhanced when macrophages polarized to M2 type. Compared with the PBS control group, the bands of phosphorylated JAK1 (p-JAK1), phosphorylated STAT6 (p-STAT6), Arg-1 and CYP1A1 were enhanced in primary peritoneal macrophages of mice in the IL-4 group, and reached the peak value at 12 hours then gradually decreased. This result indicated that the phosphorylation of JAK1/STAT6 pathway was enhanced in M2 macrophages with high expression of CYP1A1, and the pathway was activated. ② Experiment 2: after IL-4 challenge for 2 hours, the expression of Arg-1 mRNA in CYP1A1/RAW cells was significantly higher than that in NC/RAW cells (2-ΔΔCt:3.02±0.60 vs. 1.47±0.43, P < 0.05), and the protein band signal was also stronger, and both peaked at 4 hours. This indicated that CYP1A1 could promote the polarization of macrophages to M2. After IL-4 challenge for 2 hours, the expression of p-JAK1 and p-JAK3 protein bands in both cells were significantly enhanced as compared with the PBS control group, but the enhancement of p-STAT6 band in CYP1A1/RAW cells was stronger than that of NC/RAW cells, indicating that CYP1A1 promoted macrophage polarization by promoting phosphorylation of the JAK1/STAT6 pathway. In the meantime, the protein band of Akt, a downstream protein of the PI3K/Akt pathway, in CYP1A1/RAW cells was significantly lower than that of NC/RAW cells, indicating that CYP1A1 did not promote macrophage polarization through this pathway. Conclusions CYP1A1 promotes the polarization of macrophage to M2 type. The mechanism is related to promoting the phosphorylation of JAK1/STAT6 pathway.
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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 in vitro. The cells in logarithmic growth phase were collected, and then they were divided into PBS control group and IL-4 group. The treatment method was the same as experiment 1. The phosphorylations of intracellular JAK1/STAT6 and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathways in different cells at 1 hour and 2 hours after IL-4 challenge were determined by Western Blot. The mRNA and protein expressions of Arg-1 in different cells at 2 hours and 4 hours after IL-4 challenge were determined by RT-qPCR and Western Blot, respectively.@*Results@#① Experiment 1: after IL-4 challenge for 2 hours, the mRNA expressions of Arg-1 and YM1 in the primary peritoneal macrophages of mice were significantly increased as compared with the PBS control group [Arg-1 mRNA (2-ΔΔCt): 1.75±0.82 vs. 1.00±0.21; YM1 mRNA (2-ΔΔCt): 2.58±0.53 vs. 1.00±0.20, both P < 0.05] which indicated that IL-4 induced macrophage to M2 type polarization successfully. Meanwhile, the mRNA expression of CYP1A1 in polarized mouse peritoneal primary macrophages was also elevated as compared with the PBS control group, and peaked at 4 hours [CYP1A1 mRNA (2-ΔΔCt): 2.25±0.69 vs. 1.00±0.17, P < 0.01]. The results indicated that CYP1A1 expression was enhanced when macrophages polarized to M2 type. Compared with the PBS control group, the bands of phosphorylated JAK1 (p-JAK1), phosphorylated STAT6 (p-STAT6), Arg-1 and CYP1A1 were enhanced in primary peritoneal macrophages of mice in the IL-4 group, and reached the peak value at 12 hours then gradually decreased. This result indicated that the phosphorylation of JAK1/STAT6 pathway was enhanced in M2 macrophages with high expression of CYP1A1, and the pathway was activated. ② Experiment 2: after IL-4 challenge for 2 hours, the expression of Arg-1 mRNA in CYP1A1/RAW cells was significantly higher than that in NC/RAW cells (2-ΔΔCt: 3.02±0.60 vs. 1.47±0.43, P < 0.05), and the protein band signal was also stronger, and both peaked at 4 hours. This indicated that CYP1A1 could promote the polarization of macrophages to M2. After IL-4 challenge for 2 hours, the expression of p-JAK1 and p-JAK3 protein bands in both cells were significantly enhanced as compared with the PBS control group, but the enhancement of p-STAT6 band in CYP1A1/RAW cells was stronger than that of NC/RAW cells, indicating that CYP1A1 promoted macrophage polarization by promoting phosphorylation of the JAK1/STAT6 pathway. In the meantime, the protein band of Akt, a downstream protein of the PI3K/Akt pathway, in CYP1A1/RAW cells was significantly lower than that of NC/RAW cells, indicating that CYP1A1 did not promote macrophage polarization through this pathway.@*Conclusions@#CYP1A1 promotes the polarization of macrophage to M2 type. The mechanism is related to promoting the phosphorylation of JAK1/STAT6 pathway.
ABSTRACT
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.
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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 in vivo and in vitro studies that antimicrobial peptides cathelicidins not only show broad-spectrum antibacterial activity and high sensitivity to drug-resistant bacteria, but also have a good guiding effect on the immune response. This paper summarizes the reports of antimicrobial peptides cathelicidins in recent years, highlighting their research achievements in antibiosis, anti-inflammatory, chemotaxis regulation and phagocytosis, providing new ideas for the treatment of infection-related diseases.
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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 in vivo and in vitro studies that antimicrobial peptides cathelicidins not only show broad-spectrum antibacterial activity and high sensitivity to drug-resistant bacteria, but also have a good guiding effect on the immune response. This paper summarizes the reports of antimicrobial peptides cathelicidins in recent years, highlighting their research achievements in antibiosis, anti-inflammatory, chemotaxis regulation and phagocytosis, providing new ideas for the treatment of infection-related diseases.
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Infectious and inflammatory diseases are important diseases threatening human health. Without timely control, a series of complications will occur in patients, such as sepsis, inflammatory factor storm, and even lead to death. It has been found that cytochrome P4501A1 (CYP1A1) plays a key role in the development of infectious and inflammatory diseases through aromatic hydrocarbon receptor (AhR) dependent and non-dependent pathways in different cells and organs induced by different substances. The non AhR dependent regulatory mechanism of CYP1A1 and the different roles of CYP1A1 in infection and inflammation is reviewed in order to provide reference for further research on the relationship between CYP1A1 and infection and inflammation.
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Objective To determine the inhibitory effects of Ellipticine (ELL) on inflammation in lipopolysaccharide (LPS)-induced RAW264.7 cells of mouse and explore its molecular mechanism.Methods The RAW264.7 cells in log phase were challenged by LPS (10 mg/L) to induce inflammation and then treated with ELL (0.05, 0.5, 5μmol/L). At the same time the cells treated with ELL (5μmol/L) were considered as ELL control group while without any stimulation as control group. After 12 hours intervention, the content of inflammatory factors in cell supernatant was detected by enzyme linked immunosorbent assay (ELISA), and then confirmed the most suitable concentration for the next experiment. After LPS of 10 mg/L was used to challenged RAW264.7 cells to cause inflammation, 5μmol/L ELL was used for intervention, and the mRNA expressions of inflammatory cytokines were detected by reverse transcription-polymerase chain reaction (RT-PCR) after 2, 4, 6 and 12 hours; the nuclear translocation of nuclear factor-κB p65 (NF-κB p65) as well as the phosphorylation levels of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinases (p38MAPK), c-Jun N-terminal kinase (JNK), c-jun, c-fos were detected by Western Blot after 15 minutes, 30 minutes, 1 hour and 2 hours.Results ① The different proliferative potential of RAW264.7 treated with LPS (10 mg/L) and ELL (0.05, 0.5, 5μmol/L) had no significant difference comparing with control group, which indicated that ELL had no cytotoxicity with experimental concentration and had no effect on the cell proliferative potential as the result of drug interaction. The levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in supernatant were significantly increased after induced by LPS comparing with control group. However, the different concentrations of ELL could dose-dependently reverse the production of inflammatory factors, and 5μmol/L was the optimum concentration of anti-inflammatory. ② Compared with control group, the mRNA expressions of TNF-α, IL-6 were significantly increased, the nuclear translocation level of NF-κB p65 increased as well as the phosphorylation levels of ERK, p38MAPK, JNK, c-fos, c-jun after stimulated by LPS. While, the different concentration of ELL could reverse the mRNA of TNF-α, IL-6 and phosphorylation levels of JNK, c-fos, c-jun [TNF-αmRNA (2-ΔCt): 2.45± 0.19 vs. 3.41±0.32 after 2 hours, 1.20±0.11 vs. 2.11±0.21 after 4 hours, 1.68±0.09 vs. 2.51±0.31 after 6 hours;IL-6 mRNA (2-ΔCt): 3.41±0.52 vs. 4.10±0.38 after 6 hours, 1.61±0.08 vs. 3.91±0.25 after 12 hours; p-JNK/GAPDH:0.557±0.034 vs. 1.049±0.056 after 1 hour, 0.439±0.040 vs. 0.855±0.038 after 2 hours; p-c-fos/GAPDH: 0.158± 0.030 vs. 0.741±0.035 after 1 hour, 0.156±0.015 vs. 0.932±0.030 after 2 hours; p-c-jun/GAPDH: 0.425±0.036 vs. 0.802±0.059 after 1 hour, 0.345±0.075 vs. 0.952±0.068 after 2 hours; allP < 0.05]. However, it had no significant effect on the nuclear translocation level of NF-κB p65 and the phosphorylation level of ERK and p38MAPK. Conclusion ELL inhibited the production of IL-6, TNF-α inflammatory factors in LPS-induced RAW264.7 cells through suppression the phosphorylation of JNK and activator protein-1 (AP-1).
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Over the past two decades, multiple drug-resistant infections have escalated globally with the significantly increased morbidity and mortality due to the unreasonable uses of antimicrobial agents in areas such as animal husbandry, industry and medicine. As the situation of drug resistance has been progressively serious, anti-drug-resistant clinical strategies have attracted widely social concerns. This review will report the current status of antibiotic resistance and the mechanism of antibiotic-resistance all over the world. The anti-drug resistance strategies are the emphasis of our report, including the new indication of old antibiotics, the combination of existing antibiotics, the development of new antibiotics, nano-antibiotics, and non-infection treatment with immunomodulators and phage. This review aims to further understand the current situation of drug resistance, which optimizes the strategies of drug-resistant bacteria and clinical services.
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High mobility group protein B1 (HMGB1) is the most representative substance in the alarmins family, it is actively or passively release to extracellular by the activation of monocyte/macrophage and the dead cells, and then it stimulates the production of a variety of inflammatory mediators, and increases the organism's inflammatory response through relevant receptors signaling pathways. In recent years, its concentration can reflect the severity of inflammation and injury and was related to the prognosis, HMGB1 has won more and more attention in the development of sepsis. By reviewing the study of HMGB1 in sepsis pathogenesis, signal pathway and reversal measures, it was found that HMGB1 was considered as an important inflammatory mediators and warning signal involved in the pathogenesis of sepsis, and was become a new target in the treatment of sepsis. Further research on the role of HMGB1 in the pathogenesis of sepsis is needed in the future, and the development of new drugs combined with HMGB1 will be used in the study of HMGB1 in animal experiments.
ABSTRACT
Objective To investigate the protective effect of agmatine (AGM) against peritoneal inflammatory response and neutrophil (PMN) infiltration induced by zymosan (ZYM) in mice. Methods Thirty-six adult male C57BL/6 mice were randomly divided into sham group, model group, and AGM treatment group. Peritonitis model was reproduced by intra-peritoneal injection of 1 mg/mL ZYM (0.5 mL), while equivalent phosphate buffer saline (PBS) was given to sham group. 200 mg/kg AGM was injected into peritoneal cavity after ZYM challenge in AGM treatment group. Six mice in each group were sacrificed at 2 hours and 6 hours, respectively, after reproduction of the model. Blood sample and peritoneal lavage fluid (PLF) were collected. The levels of keratinocyte-derived chemokine (KC), macrophage inflammatory protein 2 (MIP-2), tumor necrosis factor-α (TNF-α), interleukins-6 (IL-6) in serum and PLF were determined by enzyme linked immunosorbent assay (ELISA). The number of leukocytes and PMN in PLF were determined by hemocytometer and flow cytometry, respectively. Results Compared with sham group, all serum and PLF levels of KC, MIP-2, TNF-α and IL-6 were greatly elevated at 2 hours after ZYM injection in model group, while AGM treatment could dramatically reduce the levels of the above-mentioned cytokines in serum and PLF as compared with those of the model group [serum KC (ng/L): 990.7±137.9 vs. 2 053.2±262.7, MIP-2 (ng/L): 642.2±124.4 vs. 1 369.7±146.5, TNF-α (ng/L): 608.6±38.1 vs. 1 044.7±101.0, IL-6 (ng/L): 1 058.2±129.1 vs. 1 443.3±190.1; PLF KC (ng/L): 7 462.3±839.6 vs. 12 723.5±1 515.7, MIP-2 (ng/L): 1 570.8±193.4 vs. 3 471.4±384.7, TNF-α (ng/L): 1 115.8±156.7 vs. 1 499.2±231.2, IL-6 (ng/L): 2 646.5±223.2 vs. 3 126.7±291.4; all P < 0.05]. The expressions of KC, MIP-2 and TNF-α at 6 hours were significantly lower than those at 2 hours in model group and AGM treatment group, but IL-6 levels were further increased. The levels of KC and MIP-2 in serum and PLF at 6 hours were decreased to the levels of sham group. At 6 hours after the reproduction of the model, the number of total inflammatory cells and PMN of PLF in the model group was significantly higher than those of the sham group. In contrast, AGM notably lowered the number of inflammatory cells and PMN in peritoneal fluid after ZYM attack [total inflammatory cells (×109/L): 14.7±1.1 vs. 2.0±0.4, 10.1±1.2 vs. 14.7±1.1; PMN (×109/L): 11.37±1.22 vs. 0.18±0.05, 7.69±0.57 vs. 11.37±1.22, all P < 0.05]. Conclusion AGM can effectively alleviate acute peritoneal inflammatory injury induced by ZYM, mainly through reducing the secretion of inflammatory mediators and chemokines, and inhibiting the infiltration of leukocytes and neutrophils.