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Objective:To evaluate the role of interleukin 1β (IL-1β)/c-Jun N-terminal kinase (JNK) pathway in sevoflurane-induced necroptosis of rat hippocampal neurons in vitro. Methods:Primarily cultured hippocampal neurons of Sprague-Dawley rat fetuses were inoculated into 96-well plates (cell density: 1×10 4 cells/ml, 200 μl/hole) and 6-well plates (cell density: 1×10 6 cells/ml, 2 ml/hole). The cells were divided into 3 groups ( n=20 each) using a random number table method after being cultured for 7 days: control group (group C), sevoflurane group (group S) and IL-1 receptor antagonist group (group I). Group C received routine culture, IL-1 receptor antagonist IL-1ra 1 μg/μl was added, and the cells were incubated for 30 min in group I, and in addition the cells were placed in the incubator containing 2% sevoflurane and cultured for 5 h at 37 ℃ in S and I groups.The cells were collected for microscopic examination of the morphology of neurons (with an inverted microscope) and for determination of the cell necroptosis rate (by flow cytometry), cell viability (by MTT method), and expression of IL-1β, interleukin-1 receptor type I (IL-1RI), interleukin-1 receptor accessory protein (IL-1RAcP), phosphorylated JNK (p-JNK) ), receptor-interacting protein 1 (RIP1), RIP3 and phosphorylated mixed lineage kinase-like (p-MLKL) (by Western blot ). Results:Compared with group C, the cell viability was significantly decreased, the necroptosis rate was increased, and the expression of IL-1β, IL-1RI, IL-1RAcP, p-JNK, RIP1, RIP3 and p-MLKL was up-regulated in group S ( P<0.05). Compared with group S, the cell viability was significantly increased, the necroptosis rate was decreased, and the expression of IL-1β, IL-1RI, IL-1RAcP, p-JNK, RIP1, RIP3 and p-MLKL was down-regulated in group I ( P<0.05). There was no obvious abnormality in the morphology of neurons in group C. The cell body of neurons was shrunk, the processes were broken, and the network between processes was sparse in group S. The cell body was round, and the morphology was close to normal in group I. Conclusion:The mechanism by which sevoflurane induces necroptosis of rat hippocampal neurons in vitro is related to activation of IL-1β/JNK pathway.
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Mannosylerythritol lipids (MELs) are glycolipids and have several pharmacological efficacies. MELs also show skin-moisturizing efficacy through a yet-unknown underlying mechanism. Aquaporin-3 (AQP3) is a membrane protein that contributes to the water homeostasis of the epidermis, and decreased AQP3 expression following ultraviolet (UV)-irradiation of the skin is associated with reduced skin moisture. No previous study has examined whether the skin-moisturizing effect of MELs might act through the modulation of AQP3 expression. Here, we report for the first time that MELs ameliorate the UVA-induced downregulation of AQP3 in cultured human epidermal keratinocytes (HaCaT keratinocytes). Our results revealed that UVA irradiation decreases AQP3 expression at the protein and messenger RNA (mRNA) levels, but that MEL treatment significantly ameliorated these effects. Our mitogen-activated protein kinase inhibitor analysis revealed that phosphorylation of c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase or p38, mediates UVA-induced AQP3 downregulation, and that MEL treatment significantly suppressed the UVA-induced phosphorylation of JNK. To explore a possible mechanism, we tested whether MELs could regulate the expression of peroxidase proliferator-activated receptor gamma (PPAR-γ), which acts as a potent transcription factor for AQP3 expression. Interestingly, UVA irradiation significantly inhibited the mRNA expression of PPAR-γ in HaCaT keratinocytes, whereas a JNK inhibitor and MELs significantly rescued this effect. Taken together, these findings suggest that MELs ameliorate UVA-induced AQP3 downregulation in HaCaT keratinocytes by suppressing JNK activation to block the decrease of PPAR-γ. Collectively, our findings suggest that MELs can be used as a potential ingredient that modulates AQP3 expression to improve skin moisturization following UVA irradiation-induced damage.
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Humans , Down-Regulation , Epidermis , Glycolipids , Homeostasis , JNK Mitogen-Activated Protein Kinases , Keratinocytes , Membrane Proteins , Peroxidase , Phosphorylation , Phosphotransferases , PPAR gamma , Protein Kinases , RNA, Messenger , Skin , Transcription Factors , WaterABSTRACT
Objective To investigate the effect of intratracheal injection of c-Jun N-terminal kinase ( JNK) siRNA plasmid on ischemia-reperfusion ( I∕R) injury in a rat model of lung transplantation. Meth-ods ExperimentⅠ Thirty-two male Wistar rats, weighing 250-280 g, were divided into 2 groups ( n=16 each) using a random number table method: control group ( group C) and JNK siRNA group. JNK siR-NA plasmid 2 mg∕kg ( diluted to 0. 2 ml in sterile phosphate buffer solution) was intratracheally injected in JNK siRNA group. Scrambled siRNA plasmid 2 mg∕kg ( diluted to 0. 2 ml in sterile phosphate buffer solu-tion) was intratracheally injected in group C. Six rats in each group were sacrificed at 48 h of administra-tion, and left lung tissues were removed for determination of the expression of JNK and JNK mRNA ( by Western blot and real-time polymerase chain reaction, respectively) . The other 10 rats left in each group were used for left lung transplantation. Experiment Ⅱ Thirty male Wistar rats, weighing 250-280 g, were divided into 3 groups ( n=10 each ) using a random number table method: sham operation group ( group S) , transplanted lung I∕R group ( group I∕R) and transplanted lung I∕R+JNK siRNA group ( group I∕R+JNK siRNA) . In group I∕R and group I∕R+JNK siRNA, the left lung transplantation was performed, and the donor lungs were obtained from the living donors in group C and group JNK siRNA, respectively. At 15 min of mechanical ventilation and 30, 60, 90 and 120 min of reperfusion, arterial blood samples were obtained for blood gas analysis, PaO2 was recorded, and the oxygenation index ( PaO2 ÷ FiO2 ) was calculated. Arterial blood samples were obtained at 120 min of reperfusion in transplanted lungs for determi-nation of concentrations of interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-α) and interferon-γ( IFN-γ) in serum ( using enzyme-linked immunosorbent assay) , and the rats were sacrificed and left lung tissues were removed for microscopic examination of the pathological changes which were scored and for de-termination of wet∕dry lung weight ratio ( W∕D ratio) , and nuclear factor kappa B ( NF-κB) and activator protein-1 ( AP-1) activities ( using enzyme-linked immunosorbent assay) . Results ExperimentⅠ Com-pared with group C, the expression of JNK and JNK mRNA was significantly down-regulated in group JNK siRNA (P<0. 05). ExperimentⅡ Compared with group S, the oxygenation index was significantly de-creased, and the concentrations of serum IL-8, TNF-α and IFN-γ, W∕D ratio, lung injury score and ac-tivities of NF-κB and AP-1 were increased in I∕R and I∕R+JNK siRNA groups ( P<0. 05) . Compared with group I∕R, the oxygenation index of receptors were significantly increased, and the concentrations of serum IL-8, TNF-α and IFN-γ, W∕D ratio, lung injury score and activities of NF-κB and AP-1 were decreased in group I∕R+JNK siRNA ( P<0. 05) . Conclusion Intratracheal injection of JNK siRNA can reduce trans-planted lung I∕R injury, and the mechanism may be related to inhibiting inflammatory responses of rats.
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Objective To investigate the effects of asymmetric dimethylarginine (ADMA) on apoptosis and phosphorylation of c-jun N-terminal kinase (JNK) in endothelial outgrowth cells (EOCs). Methods The mononuclear cells were harvested from umbilical cord blood by ficoll density gradient centrifugation, and induced into EOCs and then expanded in vitro. The identified EOCs were treated with different concentrations of ADMA (0, 1, 5, 10, 20 μmol/L) for 48 h. The adherent cells were treated with 10 μmol/L ADMA,then different concentrations of JNK specific inhibitor SP600125 (0, 5,10,20 and 40 μmol/L) were added and incubated for 48 hours. Caspase-3 activity was measured by microplate reader. Apoptotic incidences of EOCs were quantitatively determined by flow cytometry. The expression of Caspase- 3 and phosphorylase-JNK (p-JNK) were detected by Western blot assay. Results The treatment of ADMA (1-20 μmol/L) significantly induced apoptosis in EOCs by enhancing Caspase-3 express and also induced phosphorylation of JNK (P<0.05). Meantime, the JNK specific inhibitor SP600125 could attenuate the apoptosis induced by ADMA during this process (F=6.733,P<0.05) and inhibit the expression of Caspase-3 and p-JNK. Conclusion ADMA can induce apoptosis in EOC, which may be achieved by activating JNK signal transduction pathway.
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Objective To explore the impact of puerarin treatment on autophagy in rats with traumatic brain injury (TBⅠ) and the underlying mechanism.Methods Seventy five Sprague-Dawley (SD) rats were randomized into 5 groups:sham group (S group,n =15),traumatic brain injury group (TBⅠ group,n =15),TBⅠ + puerarin treatment group (TBⅠ + Pue group,n =15),TBⅠ + JNK inhibitor group (TBⅠ + SP group,n =15),and TBⅠ + JNK activator + Pue (TBⅠ + An + Pue group,n =15).Feeney method was applied to make rats with TBⅠ model.Mter that,head water content and neurological deficit score (NDS) were measured and recorded at day 1,3 and 7 in each group.Western blot was used to measure the JNK activity and autophagic marker proteins,including LC3B and Beclin1.Results Compared to S group,the head water content and NDS were decreased significantly among the others (P ＜ 0.05).The head water content and NDS in TBⅠ + Pue and TBⅠ + SP groups was decreased remarkably compared with TBⅠ group.Combined with puerarin and animycin treatments failed to reduce head water content and NDS compared to the TBⅠ + Pue group.Activated autophagy could be observed in TBⅠ group compared to S group.Compared to group S,LC3Ⅱ,Beclin1 and P-JNK1 were increased significantly.Pue and SP could reduce their expressions,respectively.Combined with puerarin and animycin treatments failed to reduce LC3Ⅱ,Beclin1 and P-JNK1 compared to TBⅠ + Pue group.Conclusions Puerarin could protect rats with TBⅠ via inhibiting autophagy,JNK signal pathway could involve the process of puerarin regulating autophagy.
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Objective To evaluate the role of c-Jun N-terminal kinase (JNK) in activation of astrocytes in midbrain periaqueductal gray (PAG) of rats with neuropathic pain.Methods A total of 72 pathogen-free male Sprague-Dawley rats,aged 9 weeks,weighing 160-200 g,were divided into 4 groups using a random number table:control group (group C,n =8),neuropathic pain group (group NP,n =40),dimethyl sulfoxide control group (group DS,n =12) and JNK inhibitor SP600125 group (group SP,n=12).Neuropathic pain was produced by chronic constriction injury (CCI).At 14 days after CCI,10 nmol JNK inhibitor SP600125 0.5 μl was intraperitoneally injected into the PAG in group SP,and 10％ dimethyl sulfoxide 0.5 μl was given instead in group DS.Eight rats were selected in group C,before CCI and at 3,7,14 and 21 days after CCI in group NP,and in DS and SP groups,and the mechanical pain threshold was measured before CCI,before administration on 14 days after CCI and at 30,45,60,75 and 90 min after administration.The rats in group C were sacrificed after the end of measurement of the mechanical pain threshold,and brains were removed for determination of phosphorylated JNK (p-JNK) and glial fibrillary acidic protein expression (by Western blot) in PAG region.The rats in group NP were sacrificed after the end of measurement of the mechanical pain threshold at each time point,and brains were removed for detection of p-JNK expression in PAG region.Four rats in DS and SP groups were sacrificed after the last measurement of the mechanical pain threshold at 45 min after administration,and brains were removed for determination of glial fibrillary acidic protein expression in PAG region.Results Compared with group C,the mechanical pain threshold was significantly decreased at each time point after CCI,and the expression of p-JNK was up-regulated at 7-21 days after CCI in group NP (P＜0.01).Compared with group DS,the mechanical pain threshold was significantly increased at 30 min after administration,and GFAP expression was down-regulated at 45 min after administration in group SP (P＜ 0.01).The mechanical pain threshold was significantly higher at 30-75 min after administration than before administration in group SP (P＜0.01).Conclusion The mechanism underlying activation of astrocytes in PAG is related to activating JNK in the rats with neuropathic pain.
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Objective To observe the effect of intrathecal injection (IT) of oxycodone hydrochloride on neuropathic pain and spinal cord level of microglial c-Jun N-terminal kinase/chemokine (C-X-C motif) ligand 1 (c-JNK/CXCL) 1signal in rat model of chronic constriction injury (CCI).Methods Male Sprague-Dawley rats were randomly divided into five groups (n =40 per group):sham group (intrathecal normal saline,IT NS),CCI group (CCI + IT NS),oxy group (CCI + IT 5 μg/30 μl oxy),mino group (CCI + IT 5 μg/30 μl Minocycline),and c-JNK inhibitor group (SP group,CCI + IT 5 μg/30 μl SP600125).The lumbar intrathecal catheters were implanted in L5-6 of rats and CCI models were established as previously described.The thermal and mechanical nociceptive thresholds were assessed by paw withdrawal latency (PWL) to radiant heat and von Frey filaments.The oxycodone,minocycline and SP600125 were administered intrathecally for 3 days before surgery.The spinal cord expression of Ⅰ ba-1,p-c-JNK and CXCL1 proteins assessed by Western blot.Immunofluorescence staining was performed to examine microglia morphology and the number of Ⅰ ba-1 positives cells in dorsal horn of injured spinal cord at 7 days post-IR.Results Compared to sham group,rats in CCI group had significantly lower mechanical and thermal pain thresholds,but higher spinal proteins expression of Ⅰ ba-1,and p-c-JNK and CXCL1 (P ＜0.05).Rats in oxy group,mino group and SP group had significantly higher mechanical and thermal pain thresholds and significantly lower proteins expression of Ⅰ ba-1,p-c-JNK and CXCL1 compared to those in CCI group (at any observed time-point after ligation,but most significantly at 7days,P ＜ 0.05).At the 7days after surgery,microglial cells in CCI group transformed from the ramified shape to amoeboid macrophage-like shape by immunofluorescence staining with the increases of Ⅰ ba-1 positive cells;while the other three groups exhibited hypertrophic morphology with less number Ⅰ ba-1 positive cells (P ＜ 0.05).There were no significant differences between these three groups at any observed time (P ＞ 0.05).Conclusions Intrathecal injection of oxycodone hydrochloride can relieve CCI-induced neuropathic pain by down-regulation microglial c-JNK/CXCL1 signal in spinal cords.Provide new therapeutic targets for clinical treatment of neuropathic pain.
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Objective To investigate the role of β-arrestin-1 in inhibition of endoxin-induced activation of MAPK signaling pathway in pulmonary microvascular endothelial cells (PMVECs) by penehyclidine hydrochloride (PHC).Methods Human PMVECs were seeded in 6-well plates (2 ml/well) or in culture flasks (4 ml/flask) at the density of 1×105 cells/ml,and randomly divided into 5 groups (n=20 each) using a random number table:empty plasmid transfection group (group C),lipopolysaccharide (LPS) + empty plasmid transfection group (LPS group),PHC + LPS + empty plasmid transfection group (P + LPS group),LPS+β-arrestin-1 short hairpin RNA (shRNA) transfection group (LPS+shRNA group),and PHC + LPS+β-arrestin-1 shRNA transfection group (P+LPS+shRNA group).After the cells were transfected with empty plasmid 1.5 μg or with plasmid containing 15 nmol/L β-arrestin-1 shRNA,the cells were incubated for 24 h.At 24 h of incubation,LPS with the final concentration of 0.1 μg/ml was added,and the cells were then incubated for 1 h in LPS and LPS+ shRNA groups.In P+LPS and P+LPS+shRNA groups,PHC with the final concentration of 2 μg/ml was added,and the cells were incubated for 1 h,and then LPS with the final concentration of 0.1 μg/ml was added,and the cells were incubated for 1 h.The expression of filamentous actin (F-actin) was detected by flow cytometry.The expression of myosin light chain kinase (MLCK) and vascular endothelial-cadherin (VE-cadherin) was detected by immunofluorescence.The expression of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and phosphorylated cJun N-terminal kinase (p-JNK) was determined by Western blot.The expression of β-arrestin-1 mRNA was determined by real-time polymerase chain reaction.Results Compared with group C,the expression of Factin,VE-cadherin and β-arrestin-1 mRNA was significantly down-regulated,and the expression of MLCK,p-ERK1/2 and p-JNK was up-regulated in group LPS,and the expression of p-ERK1/2 and p-JNK was significantly up-regulated (P＜0.05),and no significant change was found in the other parameters mentioned above in group P+LPS (P＞0.05).Compared with group LPS,the expression of F-actin,VE-cadherin and β-arrestin-1 mRNA was significantly up-regulated,and the expression of MLCK,p-ERK1/2 and p-JNK was down-regulated in group P+LPS,and the expression of F-actin,VE-cadherin and β-arrestin-1 mRNA was significantly down-regulated,and the expression of MLCK and p-JNK was up-regulated in group LPS+shRNA (P＜0.05).Compared with group P+LPS,the expression of F-actin,VE-cadherin and β-arrestin-1 mRNA was significantly down-regulated,and the expression of MLCK,p-ERK1/2 and p-JNK was up-regulated in group P+LPS+shRNA (P＜0.05).Conclusion The mechanism by which PHC inhibits endoxin-induced activation of MAPK signaling pathway in PMVECs is partially related to up-regulation of β-arrestin-1 expression.
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Objective To evaluate the effect of curcumin pretreatment on c-Jun N-terminal kinase (JNK) signaling pathway during one-lung ventilation (OLV)-induced acute lung injury in mice.Methods Ninety SPF male C57BL/6J mice,aged 6-9 weeks,weighing 18-24 g,were randomly divided into 6 groups (n=15 each) using a random number table:two-lung ventilation (TLV) group;OLV group;curcumin 100,150,200 and 250 mg/kg groups (C100,C150,C200 and C250 groups).The corresponding doses of curcumin were administered intraperitoneally at 2 h before one-lung ventilation in C100,C150,C200 and C250 groups.The animals were tracheally intubated and mechanically ventilated in volume-controlled mode.The ventilator settings were adjusted to maintain the end-tidal pressure of carbon dioxide at 35-45 mmHg.In OLV,C100,C150,C200 and C250 groups,unilateral lung was ventilated for 1.5 h followed by 0.5 h of TLV.Bilateral lungs were ventilated for 2.0 h in group TLV.Peak airway pressure and airway pressure were recorded at 1.5 h of OLV and 0.5 h of TLV.At the end of mechanical ventilation,left lungs were removed for microscopic examination of the pathologic changes,and the index of quantitative assessment for alveolar damage (IQA) was recorded.Wet/dry lung weight ratio (W/D ratio) was determined,and the cell apoptosis in lung tissues was detected using TUNEL.The apoptosis index (AI) was calculated.The expression of JNK mRNA was determined using real-time polymerase chain reaction.The expression of JNK and phosphorylated JNK was determined by Western blot.The phosphorylation of JNK was calculated.Results Compared with group TLV,the IQA,W/D ratio,AI,expression of JNK mRNA and phosphorylation of JNK were significantly increased in group OLV (P＜0.05).Compared with group OLV,the IQA,W/D ratio,AI,expression ofJNK mRNA and phosphorylation of JNK were significantly decreased in C150,C200 and C250 groups,the parameters mentioned above were significantly decreased in sequence in C100,C150,C200 and C250 groups (P＜0.05),and no significant change was found in the parameters mentioned above in group C100 (P＞ 0.05).Compared with group OLV,the pathological changes were significantly attenuated in sequence in C150,C200 and C250 groups.Conclusion The mechanism by which curcumin pretreatment reduces cell apoptosis during OLV-induced acute lung injury is related to inhibition of JNK signaling pathway activation in mice.
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Objective To investigate the role of c-Jun N-terminal kinase (JNK) signaling pathway in hyperoxia-induced expression of connective tissue growth factor (CTGF) in A549 cells.Methods The cultured A549 cells were seeded in 6-well culture plates at a density of 1 × 105 cells/ml (0.5 ml/well,24 wells in total) and were randomly divided into 4 groups (n =6 each) using a random number table:control group (group C);95％ oxygen group (group 95％ O2);room air plus SP600125 (JNK inhibitor) group (group C+SP);95％ oxygen plus SP600125 group (group 95％ O2+SP).SP600125 5 μmol/L was added to each well in C+SP and 95％ O2+SP groups.The A549 cells were incubated for 48 h in an incubator filled with room air (C and C+SP groups) or 95％ oxygen (95％ O2 and 95％ O2+SP groups).The expression of phosphorylated JNK (p-JNK) and CTGF mRNA was determined using Western blot and realtime reverse transcriptase polymerase chain reaction,respectively.Results Compared with group C,no significant change was found in the expression of p-JNK and CTGF mRNA in group C+SP (P＞0.05),and the expression of p-JNK and CTGF mRNA was significantly up-regulated in group 95％ O2 (P＜ 0.05).Compared with group 95％ O2,the expression of p-JNK and CTGF mRNA was significantly down-regulated in group 95％ O2+SP (P＜0.05).Conclusion JNK signaling pathway activation is involved in up-regulation of hyperoxia-induced CTGF mRNA expression in A549 cells.
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Objective To evaluate the role of c?Jun N?terminal kinase ( JNK) and p38 mitogen?ac?tivated protein kinase ( p38MAPK) signaling pathways in attenuation of myocardial ischemia?reperfusion ( I∕R) injury by morphine postconditioning. Methods Healthy adult male Sprague?Dawley rats, weighing 180-240 g, were used in the study. Their hearts were excised and retrogradely perfused in a Langendorff apparatus with Krebs?Ringer ( K?R) buffer saturated with 95% O2?5% O2 at 37℃. After 15 min of equili?bration, 52 isolated hearts were divided into 4 groups ( n=13 each) using a random number table: control group (group C), I∕R group, morphine postconditioning group (group MP), and morphine postcondition?ing plus anisomycin group ( group MP+A) . The hearts were continuously perfused with K?R buffer for 105 min in group C. In group I∕R, the hearts were subjected to 45 min of global ischemia by stopping perfusion with K?R buffer, followed by 60 min of reperfusion by restoration of perfusion with K?R buffer. In group MP, the hearts were subjected to 45 min of global ischemia, followed by 10 min of reperfusion with K?R buffer containing 3?0 μmol∕L morphine and then by 50 min of reperfusion with K?R buffer. In group MP+A, the hearts were subjected to 45 min of global ischemia, followed by 10 min of reperfusion with K?R buffer containing 3?0 μmol∕L morphine and 1?0 μmol∕L anisomycin ( an activator of JNK and p38MAPK) and then by 50 min of reperfusion with K?R buffer. At 60 min of reperfusion, 8 hearts in each group were selected for measurement of the myocardial infarction and amount of creatine kinase?MB ( CK?MB) released from the myocardium, and the myocardial infarct size was calculated. At 20 min of reperfusion, 5 hearts in each group were selected to detect the expression of phosphorylated JNK ( p?JNK ) , phosphorylated p38MAPK ( p?p38MAPK) and cytochrome c ( Cyt c) in myocardial tissues ( by Western blot) and content of nicotinamide adenine dinucleotide ( NAD+) in myocardial tissues ( by spectrophotometry ) . Results Compared to group C, the myocardial infarct size and amount of CK?MB released from the myocardium were significantly increased, the expression of p?JNK, p?p38MAPK and Cyt c was significantly up?regulated, and the content of NAD+ was significantly decreased in I∕R, MP and MP+A groups ( P<0?05) . Compared to group I∕R, the myocardial infarct size and amount of CK?MB released from the myocardium were signifi?cantly decreased in MP and MP+A groups, and the expression of p?JNK, p?p38MAPK and Cyt c was sig?nificantly down?regulated, and the content of NAD+ was significantly increased in group MP (P<0?05). Compared to group MP , the myocardial infarct size and amount of CK?MB released from the myocardium were significantly increased, the expression of p?JNK, p?p38MAPK and Cyt c was significantly up?regula?ted, and the content of NAD+ was significantly decreased in group MP+A (P<0?05). Conclusion The mechanism by which morphine postconditioning attenuates myocardial I∕R injury is related to inhibition of activation of JNK and p38MAPK signaling pathways in rats.
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Objective To investigate the effects of emulsified isoflurane on apoptosis in human neuroblastoma cells and the role of c-Jun N-terminal kinase (JNK) in it.Methods The human neuroblastoma SHSY-5Y cells were seeded in 96-well plates or dishes and then randomly divided into 8 groups using a random number table:control group(group C,n=24),different concentrations of lipid emulsion groups(LE1 groups [n =24],LE2 group [n =24] and LE3 group [n =72]),different concentrations of emulsified isoflurane groups (EI1 group [n=24],El2 group [n=24] and EI3 group [n=72]),and emulsified isoflurane + JNK inhibitor SP600125 group (group EI-SP,n =24).At 24 h after the cells were plated,in LE1-3 groups,30％ lipid emulsion was added to the culture medium with the final concentrations of 0.395 6,0.791 2 and 1.582 4 μl/ml,respectively;in EI1-3 groups,8％ emulsified isoflurane was added with the final concentrations of 0.56,1.12 and 2.24 mmol/L,respectively;in group EI-SP,emulsified isoflurane was added with the final concentration of 1.12 mmol/L,and SP600125 was added at 1 h before addition of emulsified isoflurane with the final concentration of 10 μmol/L;the cells were cultured normally in group C.At 6,12 and 24 h of incubation in EI3 and LE3 groups,and at 24 h of incubation or culture in the other groups,the morphology of cells was detected,the cell viability was measured using methyl thiazolyl tetrazolium assay,and the expression of JNK,phosphorylated JNK (p-JNK) and cytochrome c (Cyt c) was detected by Western blot.Results Compared with group C,the cell viability was significantly decreased,and the expression of p-JNK and Cyt c was significantly up-regulated at 24 h of incubation in group EI2 and at 12 and 24 h of incubation in group EI3,the cell viability was significantly decreased (P＜0.05),and no significant change was found in the expression of p-JNK and Cyt c in group EI-SP,and no significant change was found in the cell viability and expression of p-JNK and Cyt c in LE1-3 and EI1 groups (P＞0.05).Compared with group EI1,the cell viability was significantly decreased,and the expression of p-JNK and Cyt c was significantly up-regulated at 24 h of incubation in EI2.3 groups (P＜0.05).Compared with group EI2,the cell viability was significantly decreased,and the expression of p-JNK and Cyt c was significantly up-regulated at 24 h of incubation in group EI3,and the cell viability was significantly increased,and the expression of p-JNK and Cyt c was significantly down-regulated in group EI-SP (P＜0.05).There was no significant difference in JNK expression between the eight groups (P＞0.05).Conclusion High concentrations of emulsified isoflurane can induce apoptosis in neurons only when applied for a long time,while low concentrations do not have the effect when applied for a short time.The mechanism by which emulsified isoflurane induces neuronal apoptosis is related to activation of JNK pathway.
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Objective To investigate the role of JNK in intestinal barrier dysfunction in severe septic mice treated by hydrogen. Methods Eighty male ICR mice were randomly divided into four groups (n=20 each):sham operation group, hydrogen control group, sepsis group and hydrogen treatment group. Severe sepsis rat model was reproduced by cecal ligation and puncture (CLP). Laparotomy without CLP was performed in sham operation group and hydrogen control group. The mice in hydrogen control group and hydrogen treatment group received 1-hour inhalation of 2%hydrogen at 1 hour and 6 hours after sham operation or CLP, respectively. Ten mice of each group were selected at 20 h after CLP operation and were gavaged with fluorescein-isothiocyanate-conjugated dextran (FITC-dextran). Blood samples were obtained by cardiac puncture to measure the serum concentration of FITC-dextran 4 h after treatment with FITC-dextran . Ten mice in each group were sacrificed at 24 h after CLP operation. The colony-forming unit (CFU) numbers in the peritoneal lavage fluid were counted. The middle intestinal tissues were obtained for the measurement of tumor necrosis factor alpha (TNF-α), interleukin (IL)-1βand high mobility group box 1(HMGB1) by ELISA. The level of phosphorylated JNK (p-JNK) and the expression of tight junction protein ZO-1 and Occludin were detected by Western blot assay. The intestinal pathological changes and epithelial ultrastructure changes were observed by light microscope and transmission electron microscope (TEM). Results There was no statistical significance in clinical variables between sham operation group and hydrogen control group. Compared with sham operation group, the serum FITC-dextran concentration, the CFU numbers in the peritoneal lavage fluid, the levels of TNF-α, IL-1βand HMGB1 in intestine, and the expression of p-JNK were significantly increased, the expression of ZO-1 and Occludin were down-regulated in sepsis group(P < 0.05). There was a significant intestinal pathological injury along with epithelial ultrastrcture injury in sepsis group. Compared with sepsis group, the serum FITC-dextran concentration, the CFU numbers in the peritoneal lavage fluid, the levels of intestinal TNF-α, IL-1β and HMGB1, and the expression of p-JNK were significantly decreased, the expression of ZO-1 and Occludin were up-regulated in hydrogen treatment group(P < 0.05), and the pathological and ultrastructure damage was significantly reduced. Conclusion Hydrogen can decrease levels of proinflammatory factors and up-regulate the expression of tight junction to improve intestinal barrier dysfunction caused by severe sepsis, which is related with the inhibition of JNK signaling pathway.
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Objective To investigate expressions of phosphorylated c-Jun N-terminal kinase (p-JNK)and P38 mitogen-activated protein kinase(p-P38MAPK)in psoriasis vulgaris lesions. Methods Tissue specimens were obtained from lesions of 30 patients with psoriasis vulgaris and normal skin of 30 healthy human controls. An immunohistochemical study and Western-blot analysis were performed to measure protein expressions of p-JNK and p-P38MAPK in these skin specimens. Results As the immunohistochemical study showed, the expressions of p-JNK and p-P38MAPK(expressed as the average optical density [AOD]value for targeted proteins)were significantly higher in psoriasis vulgaris lesions than in normal skin tissues (p-JNK: 0.663 ± 0.016 vs. 0.333 ± 0.009, t = 44.869, P < 0.001; p-P38MAPK: 0.436 ± 0.011 vs. 0.306 ± 0.010, t = 21.913, P < 0.001). Western-blot analysis also showed increased protein expressions of p-JNK and p-P38MAPK in psoriasis vulgaris lesions compared with normal skin tissues (t = 20.477, 165.084, respectively, both P <0.05). Conclusion The activation of JNK and P38MAPK may be involved in the overproliferation of epidermal cells in psoriasis vulgaris lesions.
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Objective To evaluate the role of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK) signaling pathways in reduction of ischemia-reperfusion (I/R) injury by morphine preconditioning in the rats with heart failure.Methods Adult male Sprague-Dawley rats,weighing 200-230 g,in which doxorubicin 2 mg/kg was injected via the tail vein once a week for 6 consecutive weeks to induce chronic heart failure,were studied.At the end of 8th week,45 rats with chronic heart failure were randomly divided into 5 groups (n =9 each) using a random number table:sham operation group (group S),group I/R,morphine preconditioning group (group MPC),SP600125 (JNK inhibitor) + morphine preconditioning group (group MSP) and SB203580 (p38MAPK inhibitor) + morphine preconditioning group (group MSB).Myocardial I/R was induced by 30 min occlusion of the anterior descending branch of the coronary artery followed by 120 min reperfusion in each group except group S.In group MPC,the rats were subjected to 3 cycles of 5-min infusion of 0.1 mg/kg morphine via the femoral vein at 5 min interval before ischemia.In MSP and MSB groups,SP600125 0.5 mg/kg and SB203580 0.2 mg/kg were injected via the femoral vein,respectively,at 10 min before morphine preconditioning.The animals were sacrificed at 120 min of reperfusion,and the myocardial specimens were obtained for determination of the total areas of right and left ventricles (LV+RV),area at risk (AAR),infarct size (IS),and expression of PKC δ in myocardial tissues (by immunohistochemistry),and IS/AAR ratio was calculated.Results There was no significant difference in LV+RV and AAR between the five groups (P＞0.05).Compared with group S,IS and IS/AAR were significantly increased,and the expression of PKC δ was upregulated in I/R and MSB groups (P＜0.05).Compared with group I/R,IS and IS/AAR were significantly decreased,and the expression of PKC δ was down-regulated in MPC and MSP groups (P＜0.05).Compared with group MPC,IS and IS/AAR were significantly increased,and the expression of PKC δ was upregulated in group MSB (P＜0.05),and no significant change was found in the parameters mentioned above in group MSP (P＞0.05).Conclusion Activation of p38MAPK signaling pathway is involved in reduction of myocardial I/R injury by morphine preconditioning,and the mechanism is related to down-regulation of PKC δ expression in rats with heart failure;JNK signaling pathway is not involved in this process.
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Objective To explore the clinical significance of expression of MKK4 in osteosarcoma,and to discuss the relationship between MKK4 and osteosarcoma occurrence,development and prognosis.Methods The expression of MKK4 protein was determined with immunohistochemical SP method in 30 cases of osteosarcoma.Results The MKK4 was obviously expressed in both nucleus and cytoplasm in osteosarcoma.The expression of MKK4 in the cytoplasm of osteosarcoma was positively correlated with clinical stage (r =0.72,P =0.000),the expression of MKK4 in the nucleus of osteosarcoma had no correlation with clinical stage (r =0.44,P =0.080).MKK4 expression in the cytoplasm was higher in transfer osteosarcoma than no transfer osteosarcoma(x2 =9.69,P ＜0.01),while no obvious difference in the nucleus of osteosarcoma(x2 =1.00,P =1.000).Conclusion The MKK4 is highly expressed in the nucleus and cytoplasm of osteosarcoma,suggests that MKK4 may be related with the carcinogenesis development of osteosarcoma.The expression of MKK4 in the cytoplasm of osteosarcoma is related to the malignant,metastasis and prognosis of osteosarcoma,may be used as a potential prognostic indicator of judgment osteosarcoma.
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Objective To evaluate the effects of dexmedetomidine on the activity of c-Jun N-terminal kinase (JNK) during cerebral ischemia-reperfusion (I/R) in rats.Methods Eighty-one pathogen-free male Sprague-Dawley rats,aged 8 weeks,weighing 180-220 g,were randomly divided into 3 groups (n=27 each) using a random number table:sham operation group (group S);cerebral I/R group (group CI/R);dexmedetomidine group (group Dex).The rats were anesthetized with intraperitoneal 10％ chloral hydrate 300 mg/kg.Cerebral ischemia was induced by occlusion of the middle cerebral artery for 2 h followed by 24 h of reperfusion in CI/R and Dex groups.The middle cerebral artery was only exposed but not occluded in group S.Dexmedetomidine 3 μg/kg was injected via the tail vein immediately before ischemia followed by infusion at a rate of 3 μg · kg-1 · h-1until 24 h of reperfusion in group Dex,while the equal volume of normal saline was given in S and CI/R groups.The rats were sacrificed at 24 h of reperfusion,and their brains were removed for determination of cerebral infarct size (by TTC staining),brain water content ((wet weight-dry weight)/wet weight × 100％),cell apoptosis (by TUNEL) and expression of phosphorylated JNK (p-JNK) protein (by Western blot analysis).Apoptotic index was calculated.Results Compared with group S,the brain water content,apoptotic index and cerebral infarct size were significantly increased,and the expression of p-JNK was up-regulated in CI/R and Dex groups.Compared with group CI/R,the brain water content,apoptotic index and cerebral infarct size were significantly decreased,and the expression of p-JNK was down-regulated in group Dex.Conclusion Dexmedetomidine reduces cerebral I/R injury through decreasing the activity of JNK and inhibiting cell apoptosis in rats.
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Objective To evaluate the effects of dexmedetomidine (DEX) on cell apoptosis induced by endoplasmic reticulum stress and c-Jun N-terminal kinase (JNK) pathway during one-lung ventilation (OLV) in rats.Methods Sixty male Sprague-Dawley rats were randomly allocated into 6 groups (n =10 each):sham operation group (Sham group),OLV group,OLV + atipamezole (α2 receptor antagonist) group (AD group),OLV + atipamezole + DEX group (DEX+AD group),OLV + low-dose DEX group (DEX-L group) and OLV + high-dose DEX group (DEX-H group).The animals were anesthetized with 10％ chloral hydrate 4.5 ml/kg,tracheostomized and mechanically ventilated.Bilateral lungs were ventilated for 2.5 h in Sham group.The right lung was ventilated for 2.0 h followed by 0.5 h two-lung ventilation in OLV group.In DEX-L and DEX-H groups,DEX was infused intravenously for 1 h at a rate of 2.5 μg · kg-1 · h-1 and 5.0 μg · kg-1 · h-1,respectively,starting from 1 h prior to OLV.Atipamezole 250 μg/kg was injected intravenously at 1 h prior to OLV in AD group.Atipamezole 250 μg/kg was injected intravenously at the onset of DEX infusion (5.0 μg · kg-1 · h-1) in DEX+AD group.The rats were sacrificed and left lungs were removed for determination of weight to dry lung weight ratio (W/D),cell apoptosis in lung tissues (by TUNEL),and expression of glucose-regulated protein 78 (GRP78) mRNA and protein,JNK mRNA and phosphorylated JNK (p-JNK) protein (by RT-PCR and Western blot).Pathological changes of lungs were examined and the injured alveolus rate (IAR) was counted under light microscope.The changes in ultrastructure of lung tissues were observed under transmission electron microscope.Apoptosis index (AI) was calculated.Results W/D,AI and IAR were significantly higher in OLV,AD and DEX+AD group than in Sham group,while lower in DEX-L and DEX-H groups than in OLV,AD and DEX+AD groups.The pathological changes of the structure of lung tissues were observed in OLV,AD and DEX+AD groups,while the pathological changes were significantly alleviated in DEX-L and DEX-H groups.In OLV,AD and DEX + AD groups,there was apoptosis in lots of pulmonary vascular endothelial cells and alveolar epithelial cells,while cell apoptosis was significantly reduced after administration of DEX.The expression of GRP78 mRNA and protein,JNK mRNA and p-JNK protein was significantly higher in OLV,AD and DEX+AD groups than in Sham group,and lower in DEX-L and DEX-H groups than in OLV,AD and DEX +AD groups.Conclusion DEX pretreatment can protect lungs during OLV,and inhibited JNK signaling pathway and reduced cell apoptosis induced by endoplasmic reticulum stress may be involved in the mechanism.
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Objective To evaluate the effect of sinomenine on apoptosis in renal tubular epithelial cells of rats subjected to renal ischemia-reperfusion (I/R), and the relationship with C-Jun N-terminal kinase (JNK) signaling pathway.Methods Fifty-four male Wistar rats, aged 6-8 weeks, weighing 180-220 g, were randomly divided into 3 groups (n =18 each) using a random number table: sham operation group (group S), I/R group and sinomenine group (group SIN).Renal ischemia was induced by occlusion of the left renal pedicle for 45 min followed by reperfusion, and the right kidney was removed immediately after onset of reperfusion in anesthetized rats in I/R and SIN groups.In group SIN, sinomenine 60 mg/kg was injected intraperitoneally at 30 min before reperfusion, while the equal volume of normal saline was given instead of sinomenine at the same time point in S and I/R groups.Six animals in each group were selected at 0.5, 6 and 24 h of reperfusion, blood samples were collected by cardiac puncture for determination of serum creatinine (Cr) and blood urea nitrogen (BUN) concentrations.Immediately after blood sampling, the left kidney was removed for examination of pathological changes in renal tissues (with light microscopes) and for determination of phosphorylated JNK (p-JNK) and caspase-3 expression (by immune-histochemistry) and apoptosis in renal tubular epithelial cells (by TUNEL).The apoptotic rate was calculated.Results Compared with group S, the serum Cr and BUN concentrations were significantly increased, the expression of p-JNK and caspase-3 was up-regulated, and the apoptotic rate was increased in I/R and SIN groups.Compared with group I/R, the serum Cr and BUN concentrations were significantly decreased, the expression of p-JNK and caspase-3 was down-regulated, and the apoptotic rate was decreased in group SIN.The microscopic examination showed that the pathological changes of kidney were significantly attenuated in group SIN compared with group I/R.Conclusion The mechanism by which sinomenine attenuates renal I/R injury is related to inhibited activation of p-JNK signaling pathway and reduced apoptosis in renal tubular epithelial cells of rats.
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Objective To evaluate the role of spinal c?Jun N?terminal kinase ( JNK ) signaling pathway in incisional pain in rats. Methods Sixty?three adult male Sprague?Dawley rats, weighing 200-250 g, were randomly divided into 3 groups ( n=21 each) using a random number table: incisional pain group ( IP group) , dimethyl sulfoxide ( DMSO) group, and JNK inhibitor SP600125 group ( SP group) . A 1?cm longitudinal incision was made through skin, fascia and muscle of the plantar aspect of the hindpaw in anesthetized rats. In group DMSO, 10% DMSO 10 μl was injected intrathecally at 30 min before surgery. In group SP, SP600125 25 μg (in 10 μl of 10% DMSO) was injected intrathecally at 30 min before sur?gery. Six rats in each group were sacrificed, and the mechanical paw withdrawal threshold ( MWT) and thermal paw withdrawal latency ( TWL) were measured at 24 h before establishment of the model and 2, 6, 24, 48 and 72 h after establishment of the model. After measurement of the pain threshold at 24 h before establishment of the model and 6, 24, 48 and 72 h after establishment of the model, the lumbar segment of the spinal cord was removed for determination of the expression of phosphorylated JNK ( p?JNK) by im?munofluorescence. Results The MWT was significantly lower, the TWL was shorter, and the expression of p?JNK was lower at each time point after establishment of the model than at 24 h before establishment of the model in group IP (P0?05) . Conclusion Spinal JNK signaling pathway is involved in the develop?ment and maintenance of incisional pain in rats.