c-Jun N-terminal kinase-mediated Rubicon expression enhances hepatocyte lipoapoptosis and promotes hepatocyte ballooning

AIM: To clarify the relationship between autophagy and lipotoxicity-induced apoptosis, which is termed "lipoapoptosis," in non-alcoholic steatohepatitis. METHODS: Male C57BL/6J mice were fed a high-fat diet(HFD) for 12 wk, after which the liver histology and expression of proteins such as p62 or LC3 were evaluated. Alpha mouse liver 12(AML12) cells treated with palmitate(PA) were used as an in vitro model. RESULTS: LC3-Ⅱ, p62, and Run domain Beclin-1 interacting and cysteine-rich containing(Rubicon) proteins increased in both the HFD mice and in AML12 cells in response to PA treatment. Rubicon expression was decreased upon c-Jun N-terminal kinase(JNK) inhibition at both the m RNA and the protein level in AML12 cells. Rubicon knockdown in AML12 cells with PA decreased the protein levels of both LC3-Ⅱ and p62. Rubicon expression peaked at 4 h of PA treatment in AML12, and then decreased. Treatment with caspase-9 inhibitor ameliorated the decrease in Rubicon protein expression at 10 h of PA and resulted in enlarged AML12 cells under PA treatment. The enlargement of AML12 cells by PA with caspase-9 inhibition was canceled by Rubicon knockdown.CONCLUSION: The JNK-Rubicon axis enhanced lipoapoptosis, and caspase-9 inhibition and Rubicon had effects that were cytologically similar to hepatocyte ballooning. As ballooned hepatocytes secrete fibrogenic signals and thus might promote fibrosis in the liver, the inhibition of hepatocyte ballooning might provide antifibrosis in the NASH liver.

All-trans Retinoic Acid Diminishes Collagen Production in a Hepatic Stellate Cell Line via Suppression of Active Protein-1 and c-Jun N-terminal Kinase Signal

Following acute and chronic liver injury,hepatic stellate cells (HSCs) become activated to undergo a phenotypic transformation into myofibroblast-like cells and lose their retinol content,but the mechanisms of retinoid loss and its potential roles in HSCs activation and liver fibrosis are not understood.The influence of retinoids on HSCs and hepatic fibrosis remains controversial.The purpose of this study was to evaluate the effects of all-trans retinoid acid (ATRA) on cell proliferation,mRNA expression of collagen genes [procollagen α1 (Ⅰ),procollagen α1 (Ⅲ)],profibrogenic genes (TGF-β 1,CTGF,MMP-2,TIMP-1,TIMP-2,PAI-1),fibrolytic genes (MMP-3,MMP-13) and the upstream element (JNK and AP-1) in the rat hepatic stellate cell line (CFSC-2G).Cell proliferation was evaluated by measuring BrdU incorporation.The mRNA expression levels of collagen genes [procollagen α1 (Ⅰ),procollagen α1 (Ⅲ)],profibrogenic genes (TGF-β 1,CTGF,MMP-2,TIMP-1,TIMP-2,PAI-1),and fibrolytic genes (MMP-3,MMP-13) were quantitatively detected by using real-time PCR.The mRNA expression of JNK and AP-1 was quantified by RT-PCR.The results showed that ATRA inhibited HSCs proliferation and diminished the mRNA expression of collagen genes [procollagen α1 (Ⅰ),procollagen α1 (Ⅲ)] and profibrogenic genes (TGF-β 1,CTGF,MMP-2,TIMP-1,TIMP-2,PAI-1),and significantly stimulated the mRNA expression of MMP-3 and MMP-13 in HSCs by suppressing the mRNA expression of JNK and AP-1.These findings suggested that ATRA could inhibit proliferation and collagen production of HSCs via the suppression of active protein-1 and c-Jun N-terminal kinase signal,then decrease the mRNAs expression of profibrogenic genes (TGF-β 1,CTGF,MMP-2,TIMP-1,TIMP-2,PAI-1),and significantly induce the mRNA expression of MMP-3 and MMP-13.

Specific effects of c-Jun NH2-terminal kinaseinteracting protein 1 in neuronal axons

c-Jun NH2-terminal kinase（JNK）-interacting protein 3 plays an important role in brain-derived neurotrophic factor/tropomyosin-related kinase B（Trk B） anterograde axonal transport. It remains unclear whether JNK-interacting protein 1 mediates similar effects, or whether JNK-interacting protein 1 affects the regulation of Trk B anterograde axonal transport. In this study, we isolated rat embryonic hippocampus and cultured hippocampal neurons in vitro. Coimmunoprecipitation results demonstrated that JNK-interacting protein 1 formed Trk B complexes in vitro and in vivo. Immunocytochemistry results showed that when JNK-interacting protein 1 was highly expressed, the distribution of Trk B gradually increased in axon terminals. However, the distribution of Trk B reduced in axon terminals after knocking out JNK-interacting protein 1. In addition, there were differences in distribution of Trk B after JNK-interacting protein 1 was knocked out compared with not. However, knockout of JNK-interacting protein 1 did not affect the distribution of Trk B in dendrites. These findings confirm that JNK-interacting protein 1 can interact with Trk B in neuronal cells, and can regulate the transport of Trk B in axons, but not in dendrites.

Correlation between spina bifida manifesta in fetal rats and c-Jun N-terminal kinase signaling

Fetal rat models with neural tube defects were established by injection with retinoic acid at 10 days after conception. The immunofluorescence assay and western blot analysis showed that the number of caspase-3 positive cells in myeloid tissues for spina bifida manifesta was increased. There was also increased phosphorylation of c-Jun N-terminal kinase, a member of the mitogen activated protein kinase family. The c-Jun N-terminal kinase phosphorylation level was positively correlated with caspase-3 expression in myeloid tissues for spina bifida manifesta. Experimental findings indicate that abnormal apoptosis is involved in retinoic acid-induced dominant spina bifida formation in fetal rats, and may be associated with the c-Jun N-terminal kinase signal transduction pathway.

c-Jun N-terminal kinase 3 deficiency protects axotomized retinal ganglion cells via affecting mitochondria involved apoptosis pathway

AIM: To illustrate the isoform-specific role and mechanism of c-Jun N-terminal kinases(JNKs) in mouse optic nerve axotomy induced neurotrauma. METHODS: We firstly investigated the expression of JNK1, JNK2, and JNK3 in the retinal ganglion cells(RGCs) by double-immunofluorescent staining. Then we created optic nerve axotomy model in wild type as well as JNK1, JNK2, JNK3, isoform specific gene deficiency mice. With that, we checked the protein expression profile of JNKs and its active form, and quantified the survival RGCs number by immunofluorescence staining. We further explored the molecules underlying isoform specific protective effect by real-time polymerase chain reaction(PCR) and Western blotting assay. RESULTS: We found that all the three isoforms of JNKs were expressed in the RGCs. Deficiency of JNK3, but not JNK1 or JNK2, significantly alleviated optic nerve axotomyinduced RGCs apoptosis. We further established that expression of Noxa, a pro-apoptotic member of BH3 family, was significantly suppressed only in JNK3 gene deficiency mice. But tumor necrosis factor receptor 1(TNFR1) and Fas, two key modulators of death receptor mediated apoptosis pathway, did not display obvious change in the expression. CONCLUSION: It is suggested that mitochondria mediated apoptosis, but not death receptor mediated apoptosis got involved in the JNK3 gene deficiency induced RGCs protection. Our study provides a novel insight into the isoform-specific role of JNKs in neurotrauma and indicates some cues for its therapeutics.

Ceramide from sphingomyelin hydrolysis differentially mediates mitogen-activated protein kinases (MAPKs) activation following cerebral ischemia in rat hippocampal CA1 subregion

Objective： To explore the role that ceramide plays in the activation of mitogen-activated protein kinases （MAPKs） during cerebral ischemia and reperfusion. Methods： Rats were subjected to ischemia by the fourvessel occlusion （4-VO） method. The sphingomyelinase inhibitor TPCK was administered to the CA1 subregion of the rat hippocampus before inducing ischemia. Western blot was used to examine the activity of extracellular- signal regulated kinase （ERK） and c-Jun N-terminal protein kinase （JNK） using antibodies against ERK, JNK and diphosphorylated ERK and JNK. Results： At lh reperfusion post-ischemia, JNK reached its peak activity while ERK was undergoing a sharp inactivation （P 〈 0.05）. The level of diphosphorylated JNK was significantly reduced but the sharp inactivation of ERK was visibly reversed （P 〈 0.05） by the sphingomyelinase inhibitor. Conclusion： The ceramide signaling pathway is up-regulated through sphingomyelin hydrolysis in brain ischemia, promoting JNK activation and suppressing ERK activation, culminating in the ischemic lesion.

Serine-threonine protein kinase activation may be an effective target for reducing neuronal apoptosis after spinal cord injury

The signaling mechanisms underlying ischemia-induced nerve cell apoptosis are poorly understood. We investigated the effects of apoptosis-related signal transduction pathways following ischemic spinal cord injury, including extracellular signal-regulated kinase（ERK）, serine-threonine protein kinase（Akt） and c-Jun N-terminal kinase（JNK） signaling pathways. We established a rat model of acute spinal cord injury by inserting a catheter balloon in the left subclavian artery for 25 minutes. Rat models exhibited notable hindlimb dysfunction. Apoptotic cells were abundant in the anterior horn and central canal of the spinal cord. The number of apoptotic neurons was highest 48 hours post injury. The expression of phosphorylated Akt（pAkt） and phosphorylated ERK（p-ERK） increased immediately after reperfusion, peaked at 4 hours（p-Akt） or 2 hours（p-ERK）, decreased at 12 hours, and then increased at 24 hours. Phosphorylated JNK expression reduced after reperfusion, increased at 12 hours to near normal levels, and then showed a downward trend at 24 hours. Pearson linear correlation analysis also demonstrated that the number of apoptotic cells negatively correlated with p-Akt expression. These findings suggest that activation of Akt may be a key contributing factor in the delay of neuronal apoptosis after spinal cord ischemia, particularly at the stage of reperfusion, and thus may be a target for neuronal protection and reduction of neuronal apoptosis after spinal cord injury.

Mitogen-activated protein kinase phosphatase 1 protects PC12 cells from amyloid beta-induced neurotoxicity

The mitogen-activated protein kinase（MAPK） signaling pathway plays an important role in the regulation of cell growth, proliferation, differentiation, transformation and death. Mitogen-activated protein kinase phosphatase 1（MKP1） has an inhibitory effect on the p38 MAPK and JNK pathways, but it is unknown whether it plays a role in Aβ-induced oxidative stress and neuronal inflammation. In this study, PC12 cells were infected with MKP1 sh RNA, MKP1 lentivirus or control lentivirus for 12 hours, and then treated with 0.1, 1, 10 or 100 μM amyloid beta 42（Aβ42）. The cell survival rate was measured using the cell counting kit-8 assay. MKP1, tumor necrosis factor-alpha（TNF-α） and interleukin-1β（IL-1β） m RNA expression levels were analyzed using quantitative real time-polymerase chain reaction. MKP1 and phospho-c-Jun N-terminal kinase（JNK） expression levels were assessed using western blot assay. Reactive oxygen species（ROS） levels were detected using 2′,7′-dichlorofluorescein diacetate. Mitochondrial membrane potential was measured using flow cytometry. Superoxide dismutase activity and malondialdehyde levels were evaluated using the colorimetric method. Lactate dehydrogenase activity was measured using a microplate reader. Caspase-3 expression levels were assessed by enzyme-linked immunosorbent assay. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase d UTP nick end labeling method. MKP1 overexpression inhibited Aβ-induced JNK phosphorylation and the increase in ROS levels. It also suppressed the Aβ-induced increase in TNF-α and IL-1β levels as well as apoptosis in PC12 cells. In contrast, MKP1 knockdown by RNA interference aggravated Aβ-induced oxidative stress, inflammation and cell damage in PC12 cells. Furthermore, the JNK-specific inhibitor SP600125 abolished this effect of MKP1 knockdown on Aβ-induced neurotoxicity. Collectively, these results show that MKP1 mitigates Aβ-induced apoptosis, oxidative stress and neuroinflammation by inhibiting the JNK signaling pathway, thereby playing a neuroprotective role.

Role of Jun amino-terminal kinase （JNK） in apoptosis of cavernosal tissue during acute phase after cavernosal nerve injury

The present study aimed to identify which mitogen-activated protein kinase （p38 or Jun amino-terminal kinase [JNK]） was involved in cavernosal apoptosis during the acute phase after cavernosal nerve crush injury （CNCI） in rats to ameliorate apoptosis of cavernosal tissue, such as smooth muscle （SM）. A total of twenty 10-week-old male Sprague-Dawley rats were divided equally into two groups： sham surgery （S） and CNCI （I）. The I group approximated the clinical situation of men undergoing radical prostatectomy using two 60-second compressions of both CNs with a microsurgical vascular clamp. At 2-week postinjury, erectile response was assessed using electrostimulation. Penile tissues were harvested for immunohistochemistry analysis of alpha-SM actin （（x-SMA）, western blot analysis, and double immunofluorescence analysis of （x-SMA and phosphorylated p38 or JNK, as well as double immunofluorescent of TUNEL and phosphorylated p38 or JNK. At 2-week postinjury, the I group had a significantly lower intracavernous pressure （ICP）/mean arterial pressure （MAP） and a lower area under the curve （AUC）/MAP than the S group. The I group also exhibited decreased immunohistochemical staining of α-SMA, an increase in the number of SM cells positive for phosphorylated JNK, an increased number of apoptotic cells positive for phosphorylated JNK, and increased JNK phosphorylation compared with the S group. However, there was no significant difference in p38 phosphorylation expression or the number of SM cells positive for phosphorylated p38 between the two groups. In conclusion, our data suggest that JNK, not p38, is involved in cavernosal apoptosis during the acute phase after partial CN damage.

Effects of Different Therapeutic Methods and Typical Recipes of Chinese Medicine on Activation of c-Jun N-terminal Kinase in Kupffer Cells of Rats with Fatty Liver Disease

Objective： To observe the effects of different therapeutic methods and the recipes of Chinese medicine （CM） on the activation of c-Jun N-terminal kinase （JNK） in Kupffer cells of rats with fatty liver disease and to explore the mechanisms of these therapeutic methods. Methods： By using a random number table, 98 rats were randomly divided into 7 groups： control group, model group, and 5 treatment groups, including soothing Liver （Gan） recipe group, invigorating Spleen （Pi） recipe group, dispelling dampness recipe group, promoting blood recipe group, and complex recipe group. Rats in the control group were fed with normal food and distilled water by gastric perfusion, while rats in the model group were fed with high-fat food and distilled spirits by gastric perfusion. Rats in the 5 treatment groups were fed with high-fat food and corresponding recipes by gastric perfusion. Twelve weeks later, all rats were sacrificed and liver tissues were stained for pathohistological observation. Kupffer cells were isolated from livers of rats to evaluate JNK and phospho-JNK expressions by Western blotting. Results： The grade of hepatic steatosis was higher in the model group than the control group （P〈0.05）. Compared with the model group, the grade of fatty degeneration in soothing Liver recipe group and invigorating Spleen recipe group were significantly ameliorated （P〈0.05）. Expressions of JNK and phospho-JNK in Kupffer cells were significantly higher in the model group than those in the control group （P〈0.05, P〈0.01）. Compared with the model group, expressions of JNK in all treatment groups decreased, especially in invigorating Spleen recipe group and promoting blood recipe group （P〈0.05）. Compared with the model group, expressions of phospho-JNK in all treatment groups declined significantly （P〈0.01）, especially in soothing Live recipe group and invigorating Spleen recipe group. Conclusions： The high expressions of JNK and phospho-JNK in Kupffer cells might play an important role in the pathogenesis of fatty liver disease in rats. The recipes of CM, especially invigorating Spleen recipe and soothing Liver recipe, might protect liver against injury by reducing the total JNK protein content and inhibiting the activation of JNK protein in Kupffer cells of fatty liver model rats, which showed beneficial effects on fatty liver disease.

Effect of c-Jun NH2-terminal kinase-mediated p53 expression on neuron autophagy following traumatic brain injury in rats

Background Activation of c-Jun NH2-terminal kinase （JNK） has been implicated in neuron apoptosis as well as autophagy in response to various stressors after traumatic brain injury （TBI）. However, the underlying molecular pathway remains unclear. Our study assessed whether JNK-mediated p53 phosphorylation might be an important mechanism for enhancing neuron autophagy in response to TBI. Methods A total of 186 male Sprague-Dawley （SD） rats （300-350 g） were used in this study. By randomized block method rats were randomly divided into four groups： sham-operated （n=46）, TBI （n=60）, TBI ＋ dimethyl sulfoxide （DMSO） （n=40）, and TBI ＋ SP600125 （n=40）. JNK was treated with SP600125, a specific JNK inhibitor. JNK, p-P53, Beclin-1, damage-regulated autophagy modulator （DRAM） and p-bcl-2 were evaluated by Western blotting analysis. The cellular localization and expression of Beclin-1 and DRAM was observed by immunofluorescence and immunohistochemistry, and the expression of Beclin-l-Bcl-2/Bcl-xL complexes was evaluated by immunoprecipitation. Multiple-group comparisons were conducted using analysis of variance （ANOVA）. P values of less than 0.05 were considered statistically significant. Results It was observed that the expression of JNK, p-P53, Beclin-1, DRAM and p-bcl-2 was increasing after TBI, and the expression of Beclin-1 and DRAM was mainly located in the cytoplasm of neurons. But these were significantly inhibited in SP600125 group compared with sham group and TBI＋SP600125 group （P 〈0.05）. The expression of Beclin-l-Bcl-2/Bcl-xL complexes was reduced after TBI. Conclusion JNK-mediated p53 phosphorylation might be an important mechanism for enhancing neuron autophagy in response to TBI.

Inhibition of c-Jun N-terminal Kinase Signaling Pathway Alleviates Lipopolysaccharide-induced Acute Respiratory Distress Syndrome in Rats

Background： An acute respiratory distress syndrome （ARDS） is still one of the major challenges in critically ill patients. This study aimed to investigate the effect of inhibiting c-Jun N-terminal kinase （JNK） on ARDS in a lipopolysaccharide （LPS）-induced ARDS rat model. Methods： Thirty-six rats were randomized into three groups： control, LPS, and LPS ＋ JNK inhibitor Rats were sacrificed 8 h alter LPS treatment. The lung edema was observed by measuring the wet-to-dry weight （W/D） ratio of the lung. The severity of ptdmonary inflammation was observed by measuring myeloperoxidase （MPO） activity of lung tissue. Moreover, the neutrophils in bronchoalveolar lavage fluid （BALF） were cotinted to observe the airway inflammation. In addition, lung collagen accumulation was quantified by Sircol Collagen Assay. At the same time, the pulmonary histologic examination was perlbrmed, and lung injury score was achieved in all three groups. Results： MPO activity in lung tissue was found increased in rats treated with LPS comparing with that in control （I.26 ＋ 0.15 U in LPS vs. 0.77 ± 0.27 U in control, P 〈 0.05）. Inhibiting ,INK attenuated LPS-induced MPO activity upregulation （0.52 ± 0. 12 U in LPS ＋ JNK inhibitor vs. 1.26 ± 0.15 U in LPS, P 〈 0.05）. Neutrophils in BALF were also found to be increased with LPS treatment, and inhibiting ,INK attenuated LPS-induced neutrophils increase in BALF （255.0 ± 164.4 in LPS vs. 53 （44.5-103） in control vs. 127.0 ± 44.3 in LPS JNK inhibitor, P 〈 0.05）. At the same time, the lung injury score showed a reduction in LPS ＋ JNK inhibitor group comparing with that in LPS group （ 13.42 ± 4.82 vs. 7.00 ± 1.83, P 0.001 ）. However, the lung W/D ratio and the collagen in BALF did not show any difl＇erences between LPS and LPS ＋ JNK inhibitor group.Conclusions： Inhibiting JNK alleviated LPS-induced acute lung inflammation and had no effects on pulmonary edema and fibrosis..INK inhibitor might be a potential therapeutic medication in ARDS, in the context of reducing lung inflammatory.

Antinociceptive Effect of Najanalgesin from Naja Naja Atra in a Neuropathic Pain Model via Inhibition of c-Jun NH2-terminal Kinase

Background： Najanalgesin, a toxin isolated from the venom ofNaja nqja atra, has been shown to exert significant analgesic effects in a neuropathic pain model in rats. However, the molecular mechanism underlying this protective effect ofnajanalgesin is poorly understood. The present study sought to evaluate the intracellular signaling pathways that are involved in the antinociceptive effect of najanalgesin on neuropathic pain. Methods： The antinociceptive properties of najanalgesin were tested in hind paw withdrawal thresholds in response to mechanical stimulation. We analyzed the participation of the mitogen-activated protein kinase p38, extracellular-regulated kinase （ERK）, and c-Jun N-terminal kinase （JNK） by western blot analysis. This inhibition of JNK was confirmed by immunohistochemistry. Results： The phosphorylation levels of INK （as well as its downstream molecule c-Jun）, p38, and ERK were significantly increased after injury. Najanalgesin only inhibited JNK and c-Jun phosphorylation but had no effect on either ERK or p38. This inhibition of JNK was confirmed by immunohistochemistry, which suggested that the antinociceptive effect of najanalgesin on spinal nerve ligation-induced neuropathic pain in rats is associated with JNK activation in the spinal cord. Conclusion： The antinociceptive effect of najanalgesin thnctions by inhibiting the JNK in a neuropathic pain model.

Activation of c-Jun N-terminal kinase 1/2 regulated by nitric oxide is associated with neuronal survival in hippocampal neurons in a rat model of ischemia

Background C-Jun N-terminal kinase （JNK） signaling pathway plays a critical role in cerebral ischemia. Although the mechanistic basis for this activation of JNK1/2 is uncertain, oxidative stress may play a role. The purpose of this study was to investigate whether the activation of JNK1/2 is associated with the production of endogenous nitric oxide （NO）. Methods Ischemia and reperfusion （I/R） was induced by cerebral four-vessel occlusion. Sprague-Dawley （SD） rats were divided into 6 groups： sham group, I/R group, neuronal nitric oxide synthase （nNOS） inhibitor （7-nitroindazole, 7-NI） given group, inducible nitric oxide synthase （iNOS） inhibitor （2-amino-5,6-dihydro-methylthiazine, AMT） given group, sodium chloride control group, and 1% dimethyl sulfoxide （DMSO） control group. The levels of protein expression and phospho-JNK1/2 were detected by Western blotting and the survival hippocampus neurons in CA1 zone were observed by cresyl violet staining. Results The study illustrated two peaks of JNK1/2 activation occurred at 30 minutes and 3 days during reperfusion. 7-NI inhibited JNK1/2 activation during the early reperfusion, whereas AMT preferably attenuated JNK1/2 activation during the later reperfusion. Administration of 7-NI and AMT can decrease I/R-induced neuronal loss in hippocampal CA1 region. Conclusion JNK1/2 activation is associated with endogenous NO in response to ischemic insult.

M2 pyruvate kinase enhances HIV-1 transcription from its long terminal repeat

Both thymocytes and tumor cells express M2 type isoenzyme of pyruvate kinase(M2PK),which is different from R type isoenzyme of pyruvate kinase(RPK)that is expressed in erythrocytes.In this report,the effect of RPK and M2PK on the transcription of human immunodeficiency virus type 1(HIV-1)was tested.The results indicated that M2PK could enhance HIV-1 transcription from its long terminal repeat(LTR)promoter,while RPK did not have such an effect.Specific down-regulation of M2PK could inhibit HIV-1 transcription from its LTR region.Furthermore,it was found that the C terminal region of M2PK is responsible for this effect.Collectively,the cellular factor M2PK that is expressed in thymocytes could facilitate the transcription of HIV-1.

黄芪甲苷通过激活JNK/p38 MAPK信号通路对急性脑梗死模型大鼠神经功能的影响

目的分析黄芪甲苷通过激活c-Jun氨基末端激酶(JNK)/p38丝裂原活化蛋白激酶(p38 MAPK)信号通路对急性脑梗死模型大鼠神经功能的影响。方法选取50只健康SPF级SD大鼠,10只作为对照组,其余40只建立急性脑梗死模型,其中30只大鼠建模成功,将30只大鼠随机分为模型组、药物对照组、黄芪甲苷组,每组10只对建模成功的大鼠进行给药处理,对照组、模型组大鼠采用0.9%氯化钠溶液灌胃,药物对照组给予20 mg/kg阿托伐他汀灌服,黄芪甲苷组给予70 mg/kg黄芪甲苷应用液灌服,均灌胃12周。观察4组大鼠病理组织学、神经功能[神经元特异性烯醇化酶(NSE)、星形胶质源性蛋白(S100β)]、氧化应激指标[超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、丙二醛(MDA)、活性氧(ROS)]、炎性因子[肿瘤坏死因子α(TNF-α)、白介素-1β(IL-1β)、C反应蛋白(CRP)]、JNK/p38 MAPK通路相关mRNA表达量、JNK/p38 MAPK通路。结果与对照组比较,模型组、药物对照组、黄芪甲苷组SOD、CAT降低,NSE、S100β、MDA、ROS、TNF-α、IL-1β、CRP、JNK、p38 MAPK mRNA、JNK、p38 MAPK升高(P<0.05);与模型组比较,药物对照组、黄芪甲苷组SOD、CTA升高,NSE、S100β、MDA、ROS、TNF-α、IL-1β、CRP、JNK、p38 MAPK mRNA、JNK、p38 MAPK降低,(P<0.05);与药物对照组比较,黄芪甲苷组SOD、CTA升高,NSE、S100β、MDA、ROS、TNF-α、IL-1β、CRP、JNK、p38 MAPK mRNA、JNK、p38 MAPK降低(P<0.05)。结论采用黄芪甲苷对急性脑梗死模型大鼠干预,可改善大鼠氧化应激指标,降低炎性反应,使大鼠神经功能得到改善,其作用机制可能与调控JNK/p38 MAPK信号通路有关。

Analyses of N‑Terminal Pro‑Brain Natriuretic Peptide,Cardiac Troponin T,and Creatine Kinase MB in Pericardial Fluid in Sudden Cardiac Death Caused by Ischemic Heart Disease

Background:Biochemical analyses of N‑terminal pro‑brain natriuretic peptide(NT‑proBNP),cardiac troponin T(cTnT),and creatine kinase MB(CK‑MB)have been reported to be valuable for the auxiliary diagnosis of sudden cardiac death(SCD)in previous forensic studies.Aims and Objectives:The present study aimed to evaluate the diagnostic efficiency of combined analyses of NT‑proBNP,cTnT and CK‑MB in the pericardial fluid for forensic diagnosis of SCD caused by ischemic heart disease.Materials and Methods:Levels of NT‑proBNP,cTnT,and CK‑MB in the pericardial fluid of 132 medicolegal autopsy cases were obtained through electrochemiluminescence method.Results:NT‑proBNP,cTnT,and CK‑MB levels were significantly elevated in SCD cases(P<0.05).Receiver‑operating characteristics(ROC)analysis showed that NT‑proBNP,cTnT,and CK‑MB have diagnostic value for the diagnosis of SCD:NT‑proBNP,cutoff value of 2236 pg/ml;cTnT,cutoff value of 199.51 ng/ml;CK‑MB:cutoff value of 2742.5 ng/ml,and the combined analyses of these three biomarkers have better diagnostic efficiency than each single biomarker alone.Moreover,the causes of SCD were sub‑divided into acute ischemic heart disease,acute myocardial infarction(AMI),and recurrent myocardial infarction subgroups for further analysis,which revealed that the ratio of cTnT/CK‑MB could be used to distinguish AMI with the cutoff value of 0.1085 estimated by ROC analysis.Conclusion:These observations suggested that the postmortem biochemical analyses of NT‑proBNP,cTnT,and CK‑MB in the pericardial fluid may assist to diagnose SCD in forensic practice,and the combined analyses of multiple biomarkers have better diagnostic efficiency than each single biomarker alone.On the basis of the postmortem biochemical analyses of NT‑proBNP,cTnT and CK‑MB,combining the ratio of cTnT/CK‑MB could be used to distinguish AMI.

瓜蒌皮注射液调控JNK/p38通路对缺氧/复氧诱导的心肌细胞损伤和凋亡的影响

目的探究瓜蒌皮注射液通过调节c-Jun N末端激酶/p38丝裂原活化蛋白激酶(JNK/p38)通路提高缺氧/复氧损伤条件下心肌细胞活力及抑制其凋亡的作用及可能机制。方法使用H9c2心肌细胞构建缺氧/复氧(H/R)模型,随后根据处理情况将细胞分为对照组、H/R组、H/R+瓜蒌皮组和H/R+瓜蒌皮+茴香霉素组。通过细胞计数试剂盒(CCK-8)检测各组细胞活力,试剂盒检测各组细胞中乳酸脱氢酶(LDH)、半胱天冬酶3(Caspase 3)活性;采用末端脱氧核苷酸转移酶介导的dUTP末端标记法(TUNEL)检测各组细胞凋亡并采用免疫印迹(WB)检测各组细胞中凋亡相关蛋白如B细胞淋巴瘤2(BCL-2)、BCL-2相关的X蛋白(BAX)、前半胱天冬蛋白3(Pro-caspase 3)、裂解的半胱天冬酶3(Cleaved-caspase 3)及JNK/p38通路蛋白表达。结果与对照组相比,H/R组的细胞活力显著降低,LDH和Caspase 3活性显著增加,细胞凋亡率升高,促凋亡蛋白BAX、Pro-caspase 3、Cleaved-caspase 3的表达上升,而抗凋亡蛋白Bcl-2的表达下降;同时,JNK/p38通路蛋白(JNK、p-JNK、p38、p-p38)的表达水平也显著升高,差异有统计学意义(P<0.05)。与H/R组相比,不同浓度的瓜蒌皮注射液处理后细胞活力均有所提升,尤其是2%瓜蒌皮注射液组表现出最佳效果(P<0.05)。与H/R组相比,H/R+瓜蒌皮组以及H/R+瓜蒌皮+茴香霉素组的细胞活力均显著升高,且两组的LDH和Caspase 3活性降低,细胞凋亡率及促凋亡蛋白(BAX、Pro-caspase 3、Cleaved-caspase 3)的表达下降,抗凋亡蛋白Bcl-2的表达上升,JNK/p38通路蛋白(JNK、p-JNK、p38、p-p38)的表达受到抑制(P<0.05)。与H/R+瓜蒌皮组相比,H/R+瓜蒌皮+茴香霉素组细胞活力受到抑制,LDH和Caspase 3活性升高;BAX、Pro-caspase 3、Cleavedcaspase 3及JNK、p-JNK、p38、p-p38的表达显著上升,而Bcl-2表达下降(P<0.05)。结论瓜蒌皮注射液能够通过抑制JNK/p38通路的激活增加细胞活力并减少细胞凋亡。

冠心宁通过TNFAIP3-ASK1/JNK通路对动脉粥样硬化血管平滑肌细胞表型转换的调控作用

目的探讨冠心宁(GXN)调控动脉粥样硬化(AS)斑块稳定性的分子机制。方法制备含有GXN药物的血清,利用氧化低密度脂蛋白(ox-LDL)诱导血管平滑肌细胞(VSMC)构建AS体外模型,Western blot和qPCR检测VSMC表型转换情况。通过沉默肿瘤坏死因子α诱导蛋白3(TNFAIP3),检测GXN对VSMC表型转换的影响。构建凋亡信号调节激酶1(ASK1)过表达载体,并利用Lip3000转染进细胞,检测GXN是否通过凋亡信号调节激酶1/c-Jun氨基末端激酶(ASK1/JNK)通路发挥作用。结果与对照组比较,ox-LDL组的细胞表型转换,表现为I型胶原蛋白(COLIA1和COLIA2)、TNFAIP3和α-平滑肌肌动蛋白(α-SMA)的表达水平降低(均P<0.01),基质金属蛋白酶(MMP)2、MMP9、MMP13、骨桥蛋白(OPN)、ASK1磷酸化与ASK1比值(p-ASK1/ASK1)、JNK磷酸化与JNK比值(p-JNK/JNK)升高(均P<0.01);GXN处理后VSMC表型转换为收缩型,表现为与ox-LDL组相比COLIA1、COLIA2和α-SMA水平增高(均P<0.01),MMP2、MMP9、MMP13、OPN、TNFAIP3的表达水平、p-ASK1/ASK1以及p-JNK/JNK都降低(均P<0.01)。沉默TNFAIP3后,与ox-LDL+10%GXN+sh-NC组相比,COLIA1、COLIA2、TNFAIP3和α-SMA水平降低(均P<0.01),MMP2、MMP9、MMP13、OPN、p-ASK1/ASK1以及p-JNK/JNK都升高(均P<0.01)。过表达ASK1后,与ox-LDL+10%GXN+oe-NC组相比,COLIA1、COLIA2和α-SMA的表达水平降低(均P<0.01),MMP2、MMP9、MMP13、OPN、p-ASK1/ASK1以及p-JNK/JNK都升高(均P<0.01)。结论GXN可能通过TNFAIP3调控ASK1/JNK通路介导VSMC表型转换,从而起到稳定动脉硬化斑块的作用。

黄连碱预处理对心肌缺血再灌注损伤大鼠JNK/p38MAPK信号通路的影响

目的:探讨黄连碱预处理对心肌缺血再灌注(MI/RI)大鼠c-Jun氨基末端激酶(JNK)/促分裂素原活化蛋白激酶(p38MAPK)信号通路的影响。方法:将60只大鼠随机分为MI/RI组、假手术组、黄连碱低剂量组(黄连碱-L组,50 mg/kg黄连碱)、黄连碱中剂量组(黄连碱-M组,100 mg/kg黄连碱)、黄连碱高剂量组(黄连碱-H组,200 mg/kg黄连碱)及黄连碱-H+激活剂组(50 mg/kg黄连碱+25 mg/L JNK/p38MAPK通路激活剂茴香霉素),每组10只。除假手术组外,其余各组均进行冠状动脉结扎构建MI/RI大鼠模型,造模后,观察血流动力学参数左室内压最大上升(LVdp/dt_(max))、左室内压最大下降速率(LVdp/dt_(min))、收缩压以及舒张末压变化;采集大鼠腹部主动脉血,评估心肌损伤程度指标肌酸激酶同工酶(CK-MB)及乳酸脱氢酶(LDH)含量;分离心肌组织,检测心肌组织病理学变化、细胞凋亡、炎性因子[肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)]水平及JNK/p38MAPK通路相关蛋白表达。结果:与假手术组比较,MI/RI组存在大量炎性细胞浸润、组织结构紊乱,病理损伤严重,LVdp/dt_(max)、LVdp/dt_(min)、收缩压均降低,但凋亡率、舒张压、LDH、CK-MB、TNF-α、IL-6含量、p-JNK/JNK、p-p38MAPK/p38MAPK表达增加(P<0.05);与MI/RI组比较,黄连碱-L组、黄连碱-M组、黄连碱-H组病理损伤得到改善,LVdp/dt_(max)、LVdp/dt_(min)、收缩压均增加,凋亡率、舒张压、LDH、CK-MB、TNF-α、IL-6含量、p-JNK/JNK、p-p38MAPK/p38MAPK表达降低(P<0.05);与黄连碱-H组比较,黄连碱-H+激活剂组病理损伤进一步加剧,LVdp/dt_(max)、LVdp/dt_(min)、收缩压均降低,但凋亡率、舒张压、LDH、CK-MB、TNF-α、IL-6含量、p-JNK/JNK、p-p38MAPK/p38MAPK表达增加(P<0.05)。结论:黄连碱预处理可通过抑制JNK/p38MAPK通路减轻MI/RI大鼠心肌损伤。