Role of JNK/AP-1 signaling pathway in paraquat-induced activation of NLRP3 inflammasome in microglia / 环境与职业医学

Background Paraquat (PQ) is one of the environmental factors that can cause sporadic Parkinson's disease (PD). Microglia-mediated neuroinflammation plays an important role in the occurrence and development of PD. Our previous studies have found that low doses of PQ can activate BV-2 microglia to the M1 phenotype and exert pro-inflammatory effects, but the associated mechanism is not clear yet. Objective To explore the role of c-Jun N-terminal kinase (JNK)/activator protein 1 (AP-1) signaling pathway in PQ-induced activation of the NOD-like receptor thermal protein domain associated protoin 3 (NLRP3) inflammasome in microglia. Methods An in vitro microglia model was established. The cells were treated with 0, 0.03, 0.06,and 0.12 μmol·L−1 PQ for 24 h, the whole cell protein was extracted. The relative expression levels of JNK, AP-1 constituent proteins (c-Jun, c-Fos), NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), caspasse-1 precursor (pro caspase-1), interleukin-18 (IL-18), and interleukin-1β (IL-1β) were evaluated by Western blotting, to observe the effects of PQ exposure on JNK/AP-1 signaling pathway and NLRP3 inflammasome. After the treatment of 20 μmol·L−1 JNK inhibitor SP600125, the above proteins were detected again, to explore the driving effect of JNK/AP-1 signaling pathway on NLRP3 inflammasome activation. Results After PQ exposure, the relative expression levels of key proteins of JNK, c-Jun, and c-Fos, NLRP3, ASC, and pro caspase-1 in the 0.06 μmol·L−1 PQ group and the 0.12 μmol·L−1 PQ group were higher than those in the 0 μmol·L−1 PQ group (P＜0.05), and the relative expression levels of IL-18 and IL-1β increased with higher exposure (P＜0.05). After the treatment of JNK inhibitor SP600125, the relative expression levels of key proteins of JNK/AP-1 signaling pathway (JNK, c-Jun, and c-Fos), NLRP3 inflammasome (NLRP3, ASC, and Pro caspase-1), and inflammatory factors (IL-18 and IL-1β) in the control group, the 20 μmol·L−1 SP600125 group, and the 20 μmol·L−1 SP600125+0.06 μmol·L−1 PQ group were lower than those in the 0.06 μmol·L−1 PQ group (P＜0.05). Conclusion PQ exposure can activate the JNK/AP-1 signaling pathway and subsequently drive the activation of NLRP3 inflammasome in BV-2 microglia to mediate neuroinflammatory responses..

Gold nanorods-mediated efficient synergistic immunotherapy for detection and inhibition of postoperative tumor recurrence

Tumor recurrence after surgery is the main cause of treatment failure. However, the initial stage of recurrence is not easy to detect, and it is difficult to cure in the late stage. In order to improve the life quality of postoperative patients, an efficient synergistic immunotherapy was developed to achieve early diagnosis and treatment of post-surgical tumor recurrence, simultaneously. In this paper, two kinds of theranostic agents based on gold nanorods (AuNRs) platform were prepared. AuNRs and quantum dots (QDs) in one agent was used for the detection of carcinoembryonic antigen (CEA), using fluorescence resonance energy transfer (FRET) technology to indicate the occurrence of

Effect of Xintongtai Regulating p38 MAPK/AP-1 on Traditional Chinese Medicine Syndrome Score and Collagen Fibers in VSMCs of Rabbits with Atherosclerosis： An Exploration Based on Theory of Heart Receiving Qi From Spleen / 中国实验方剂学杂志

Objective:To explore the effects of Xintongtai （XTT） on traditional Chinese medicine （TCM） syndrome score and collagen fibers in vascular smooth muscle cells（VSMCs） of rabbits with atherosclerosis in the regulation of p38 mitogen-activated protein kinase （p38 MAPK）/activator protien-1 （AP-1）signaling pathway. Method:A total of 120 rabbits of SPF grade were randomly divided into the sham operation group， combined phlegm and blood stasis model group， rosuvastatin group， and low-， middle-， and high-dose XTT groups. The rabbit model of atherosclerosis due to combined phlegm and blood stasis was established by exposing them to high-fat diet and balloon injury. Following modeling， the corresponding drugs were administered by gavage for eight weeks （2.3， 4.6， 9.2 g·kg^-1 for low-， middle-， and high-dose XTT groups and 0.55 mg·kg^-1for rosuvastatin group）. At the end of medication， the abdominal aorta was isolated and stained with htoxylin-eosin （HE） for observing the vulnerable plaque. Matrix metalloproteinase-9 （MMP-9） and tissue inhibitor of metalloproteinase-1 （TIMP-1） were detected by immunohistochemistry （IHC）. The collagen fiber decomposition in VSMCs was observed after Masson staining. The protein expression levels of p38 MAPK and AP-1 in aorta was assayed by Western blotting. The combined phlegm and blood stasis syndrome was scored based on TCM syndrome scoring scale. Result:Compared with the model group， XTT at each dose and rosuvastatin significantly decreased MMP-9 content， increased TIMP-1， down-regulated p38 MAPK protein expression， and weakened the nuclear translocation of AP-1 （<italic>P</italic><0.01）. Compared with the low-dose XTT group， the middle- and high-dose XTT groups and rosuvastatin group exhibited obviously lowered MMP-9，elevated TIMP-1， down-regulated p38 MAPK protein expression， and diminished AP-1 nuclear translocation （<italic>P</italic><0.05，<italic>P</italic><0.01）. The TCM syndrome scores of the middle- and high-dose XTT groups and rosuvastatin group were significantly improved as compared with that in the model group （<italic>P</italic><0.05，<italic>P</italic><0.01）. The comparison with the low-dose XTT group revealed a remarkable improvement in TCM syndrome score of the middle- and high-dose XTT groups and rosuvastatin group （<italic>P</italic><0.01）. As demonstrated by Masson staining， the smooth muscle fibers in the model group were arranged in disorder， accompanied by enhanced collagen decomposition， thinned fibrous cap， and increased plaque vulnerability. Compared with the model group， the VSMCs in each XTT group and rosuvastatin group were orderly arranged， manifested as decreased collagen fiber decomposition and increased plaque stability. Conclusion:XTT down-regulates the expression of p38 MAPK and MMP-9， increases the level of TIMP-1， reduces the nuclear translocation of AP-1， diminishes the decomposition of collagen fibers in VSMCs， and improves the score of combined phlegm and blood stasis syndrome. XTT alleviates arteriosclerosis due to combined phlegm and blood stasis by regulating p38 MAPK/AP-1 signaling pathway and downstream cytokines and stabilizing vulnerable plaques.

Isorhapontigenin protects against doxorubicin-induced cardiotoxicity

As an effective anticancer drug, the clinical limitation of doxorubicin (Dox) is the time- and dose-dependent cardiotoxicity. Yes-associated protein 1 (YAP1) interacts with transcription factor TEA domain 1 (TEAD1) and plays an important role in cell proliferation and survival. However, the role of YAP1 in Dox-induced cardiomyopathy has not been reported. In this study, the expression of YAP1 was reduced in clinical human failing hearts with dilated cardiomyopathy and Dox-induced

Xenobiotic receptors in mediating the effect of sepsis on drug metabolism

Sepsis is an infection-induced systemic inflammatory syndrome. The immune response in sepsis is characterized by the activation of both proinflammatory and anti-inflammatory pathways. When sepsis occurs, the expression and activity of many inflammatory cytokines are markedly affected. Xenobiotic receptors are chemical-sensing transcription factors that play essential roles in the transcriptional regulation of drug-metabolizing enzymes (DMEs). Xenobiotic receptors mediate the functional crosstalk between sepsis and drug metabolism because the inflammatory cytokines released during sepsis can affect the expression and activity of xenobiotic receptors and thus impact the expression and activity of DMEs. Xenobiotic receptors in turn may affect the clinical outcomes of sepsis. This review focuses on the sepsis-induced inflammatory response and xenobiotic receptors such as pregnane X receptor (PXR), aryl hydrocarbon receptor (AHR), glucocorticoid receptor (GR), and constitutive androstane receptor (CAR), DMEs such as CYP1A, CYP2B6, CYP2C9, and CYP3A4, and drug transporters such as p-glycoprotein (P-gp), and multidrug resistance-associated protein (MRPs) that are affected by sepsis. Understanding the xenobiotic receptor-mediated effect of sepsis on drug metabolism will help to improve the safe use of drugs in sepsis patients and the development of new xenobiotic receptor-based therapeutic strategies for sepsis.

Solute carrier transporters: the metabolic gatekeepers of immune cells

Solute carrier (SLC) transporters meditate many essential physiological functions, including nutrient uptake, ion influx/efflux, and waste disposal. In its protective role against tumors and infections, the mammalian immune system coordinates complex signals to support the proliferation, differentiation, and effector function of individual cell subsets. Recent research in this area has yielded surprising findings on the roles of solute carrier transporters, which were discovered to regulate lymphocyte signaling and control their differentiation, function, and fate by modulating diverse metabolic pathways and balanced levels of different metabolites. In this review, we present current information mainly on glucose transporters, amino-acid transporters, and metal ion transporters, which are critically important for mediating immune cell homeostasis in many different pathological conditions.

Effect of Panax Notoginseng Saponins on Breast Cancer Cell Line 4T1 in Tumor-bearing Mice Through MEKK1/SEK1/JNK1/AP-1 Pathway / 中国实验方剂学杂志

Objective:To explore the potential mechanisms of Panax Notoginseng Saponins （PNS） on growth inhibition of breast cancer cell line 4T1 in tumor-bearing mice by investigating the mitogen-activated protein kinase kinase kinase 1 （MEKK1）/stress activated protein kinase （SAPK）/extracellular regulated protein kinases （Erk） Kinase （SEK1）/c-Jun N-terminal kinase 1 （JNK1）/activator protein-1 （AP-1） signaling pathways. Method:The 4T1 breast cancer mice model was established. Forty-eight mice with successful modeled and randomly divided into the low， medium and high-dose PNS groups （10， 20， 40 mg·kg-1） and the model control group （12 mice in each group）. The PNS groups received intraperitoneal injection with dosage of 10 mL·kg-1， while the controlled group was given the same dosage of saline. After administration with PNS for 28 days， tumor tissues were isolated， weighed， sliced and homogenized. Tumor cell apoptosis was detected by TdT mediated-dUTP nick end labeling （TUNEL） staining. The mRNA expressions of MEKK1， SEK1， JNK1 and AP-1 in tumor tissue were detected by Real-time polymerase chain reaction（Real-time PCR）. The protein expressions of MEKK1， SEK1， JNK1 and AP-1 in tumor tissue were detected by immunofluorescence staining and Western blot. Result:Compared with model group， the tumor weights of medium-dose and high-dose PNS groups were decreased significantly （P<0.05）. TUNEL staining showed that the number of apoptotic tumor cells increased with the rise of dosage of PNS （P<0.05）. The medium-dose and high-dose PNS groups showed a significant increase in the mRNA expressions of MEKK1， SEK1， JNK1 and AP-1 as well as the protein expressions of MEKK1， SEK1， JNK1 and AP-1 in tumor tissues （P<0.05）， with statistically significant differences （P<0.05）. Conclusion:PNS could inhibit the tumor growth of breast cancer cell line 4T1 in tumor-bearing mice， which may be related to the activation of MEKK1/SEK1/JNK1/AP-1 signaling pathways.

Effect of Shaoyaotang on Expressions of AP-1 and TNF-α in Colon of Rats with Hygrothermal Ulcerative Colitis / 中国实验方剂学杂志

Objective: To observe the effect of Shaoyaotang on mRNA and protein expressions of colon tissue activated protein-1 (AP-1) and tumor necrosis factor-α (TNF-α) of hot and humid-type intrinsic ulcerative colitis (UC) model in rats, in order to explore the mechanism of action of herbaceous peony decoction in the treatment of UC. Method: Totally 60 Wistar rats were randomly divided into blank group, model group, SASP group, and low, medium and high-dose Shaoyaotang groups. The damp-heat intrinsic UC rat model was replicated based on integrated disease and syndrome, namely, high-fat and high-sugar spicy food and immune complex method combined with 2,4,6-trinitrobenzene sulfolnic acid (TNBS) and ethanol complex method. After the successful modeling, low, medium and high-dose Shaoyaotang (6, 12, 24 g·kg-1) was given by gavage, and 1 g·kg-1 dose of salazol sulfadiazine was given to by gavage. The blank group was given constant volume normal saline for 21 d. Real-time fluorescence quantitative polymerase chain reaction(Real-time PCR) was used to detect mRNA expressions of AP-1 and TNF-α in colon tissues, and Western blot was used to detect protein expressions of AP-1 and TNF-α in colon tissues. Result: Compared with the blank group, relative mRNA and protein expressions of AP-1, TNF-α in the model group were significantly increased (Pα in the treatment groups were significantly decreased (PConclusion: Shaoyaotang can inhibit the expression of TNF-α and stimulate AP-1 protein expression in rats with damp-heat UC.

Mechanisms of Retinoic Acid-AP-1 Signaling Pathway Modulating Secretion of TGF-β2 by Retinal Pigment Epithelial Cells / 中山大学学报(医学科学版)

@#【Objective】To investigate the effects of up-regulating RA signal and inhibiting AP-1 transcriptional activity on TGF-β2 secretion by RPEs and its possible pathways.【Methods】① To investigate the effects of ATRA treat⁃ ment，human retinal pigment epithelial cell line ARPE-19 cells were divided into 5 groups：control group and 4 interven⁃ tion groups（6 h，12 h，24 h and 48 h after RA treatment）. Western blot，RT-qPCR and immunofluorescence staining were carried out to analyze RARβ and c-Fos expression. ②To investigate the effects of RARβ inhibitor LE540 treatment on expression of RARβ and c-Fos that were induced by ATRA，ARPE-19 cells were divided into 4 groups：control group，ATRA group，LE540 group and ATRA+LE540 group. RARβ and c-Fos expression was assessed by western blot and RT-qPCR. ③ To investigate the effects of AP-1 inhibitor T-5224 treatment，ARPE-19 cells were divided into 4 groups：control group and treatment groups（12 h，24 h and 48 h after T-5224 treatment）. EMSA was carried out to ana⁃ lyze the AP-1 DNA binding activity. ④To investigate the effects of LE540 and T-5224 administration on ATRA- induced TGF-β2 secretion，ARPE-19 cells were divided into 4 groups：control group，ATRA group，ATRA+LE540 group and ATRA+LE540 group. Western blot and ELISA were carried out to analyze TGF-β2 secretion in ARPE-19 cells.【Results】 RARβ level in ARPE-19 cells was significantly higher in treatment group than in control group after being treated with ATRA for 24 and 48 hours（P＜0.05）. C-Fos level was first up-regulated and then decreased. After treatment with ATRA for 6 and 12 hours，c-Fos expression were significantly upregulated（P＜0.01），but at 48 h after treatment，their expression were significantly decreased to the level which had no statistical difference compared with the control group （P＞0.05）. The AP-1 DNA binding activity was significantly decreased in ARPE-19 cells after being treated with T-5224 for 24 and 48 hours（P＜0.01）. Compared with ATRA group，TGF-β2 secretion was statistically down-regulated after being treated with LE540 and T-5224 for 48 hours（P＜0.05）.【Conclusion】ATRA can induce TGF-β2 secretion in RPE cells through affecting RARβ expression and AP-1 transcriptional activity.

Secalonic acid D induces cell apoptosis in both sensitive and ABCG2-overexpressing multidrug resistant cancer cells through upregulating c-Jun expression

Secalonic acid D (SAD) could inhibit cell growth in not only sensitive cells but also multidrug resistant (MDR) cells. However, the molecular mechanisms need to be elucidated. Here, we identified that SAD possessed potent cytotoxicity in 3 pairs of MDR and their parental sensitive cells including S1-MI-80 and S1, H460/MX20 and H460, MCF-7/ADR and MCF-7 cells. Furthermore, SAD induced cell G2/M phase arrest the downregulation of cyclin B1 and the increase of CDC2 phosphorylation. Importantly, JNK pathway upregulated the expression of c-Jun in protein level and increased c-Jun phosphorylation induced by SAD, which was linked to cell apoptosis c-Jun/Src/STAT3 pathway. To investigate the mechanisms of upregulation of c-Jun protein by SAD, the mRNA expression level and degradation of c-Jun were examined. We found that SAD did not alter the mRNA level of c-Jun but inhibited its proteasome-dependent degradation. Taken together, these results implicate that SAD induces cancer cell death through c-Jun/Src/STAT3 signaling axis by inhibiting the proteasome-dependent degradation of c-Jun in both sensitive cells and ATP-binding cassette transporter sub-family G member 2 (ABCG2)-mediated MDR cells.

Kinsenoside attenuates osteoarthritis by repolarizing macrophages through inactivating NF-B/MAPK signaling and protecting chondrocytes

The objective was to investigate the effect of kinsenoside (Kin) treatments on macrophage polarity and evaluate the resulting protection of chondrocytes to attenuate osteoarthritis (OA) progression. RAW264.7 macrophages were polarized to M1/M2 subtypes then administered with different concentrations of Kin. The polarization transitions were evaluated with quantitative real-time polymerase chain reaction (qRT-PCR), confocal observation and flow cytometry analysis. The mechanism of Kin repolarizing M1 macrophages was evaluated by Western blot. Further, macrophage conditioned medium (CM) and IL-1 were administered to chondrocytes. Micro-CT scanning and histological observations were conducted on anterior cruciate ligament transection (ACLT) mice with or without Kin treatment. We found that Kin repolarized M1 macrophages to the M2 phenotype. Mechanistically, Kin inhibited the phosphorylation of IB, which further reduced the downstream phosphorylation of P65 in nuclear factor-B (NF-B) signaling. Moreover, Kin inhibited mitogen-activated protein kinases (MAPK) signaling molecules p-JNK, p-ERK and p-P38. Additionally, Kin attenuated macrophage CM and IL-1-induced chondrocyte damage. , Kin reduced the infiltration of M1 macrophages, promoted M2 macrophages in the synovium, inhibited subchondral bone destruction and reduced articular cartilage damage induced by ACLT. All the results indicated that Kin is an effective therapeutic candidate for OA treatment.

15-Deoxy-Δ(12,14)-prostaglandin J₂ Upregulates the Expression of 15-Hydroxyprostaglandin Dehydrogenase by Inducing AP-1 Activation and Heme Oxygenase-1 Expression in Human Colon Cancer Cells

BACKGROUND: Abnormal upregulation of prostaglandin E₂ (PGE₂) is considered to be a key oncogenic event in the development and progression of inflammation-associated human colon cancer. It has been reported that 15-hydroxyprostaglandin dehydrogenase (15-PGDH), an enzyme catabolizing PGE₂, is ubiquitously downregulated in human colon cancer. 15-Deoxy-Δ(12,14)-prostaglandin J₂ (15d-PGJ₂), a peroxisome proliferator-activated receptor γ ligand, has been shown to have anticarcinogenic activities. In this study, we investigate the effect of 15d-PGJ₂ on expression of 15-PGDH in human colon cancer HCT116 cells. METHODS: HCT116 cells were treated with 15d-PGJ₂ analysis. The expression of 15-PGDH in the treated cells was measured by Western blot analysis and RT-PCR. In addition, the cells were subjected to a 15-PGDH activity assay. To determine which transcription factor(s) and signaling pathway(s) are involved in 15d-PGJ₂-induced 15-PGDH expression, we performed a cDNA microarray analysis of 15d-PGJ₂-treated cells. The DNA binding activity of AP-1 was measured by an electrophoretic mobility shift assay. To determine whether the AP-1 plays an important role in the 15d-PGJ₂-induced 15-PGDH expression, the cells were transfected with siRNA of c-Jun, a major subunit of AP-1. To elucidate the upstream signaling pathways involved in AP-1 activation by 15d-PGJ₂, we examined its effect on phosphorylation of Akt by Western blot analysis in the presence or absence of kinase inhibitor. RESULTS: 15d-PGJ₂ (10 μM) significantly upregulated 15-PGDH expression at the mRNA and protein levels in HCT-116 cells. 15-PGDH activity was also elevated by 15d-PGJ₂. We observed that genes encoding C/EBP delta, FOS-like antigen 1, c-Jun, and heme oxygenase-1 (HO-1) were most highly induced in the HCT116 cells following 15d-PGJ₂ treatment. 15d-PGJ₂ increased the DNA binding activity of AP-1. Moreover, transfection with specific siRNA against c-Jun significantly reduced 15-PGDH expression induced by 15d-PGJ₂. 15d-PGJ₂ activates Akt and a pharmacological inhibitor of Akt, LY294002, abrogated 15d-PGJ₂-induced 15-PGDH expression. We also observed that an inhibitor of HO-1, zinc protoporphyrin IX, also abrogated upregulation of 15-PGDH and down-regulation of cyclooxygenase-2 expression induced by 15d-PGJ₂. CONCLUSIONS: These finding suggest that 15d-PGJ₂ upregulates the expression of 15-PGDH through AP-1 activation in colon cancer HCT116 cells.

The Effect of Adiponectin on the Regulation of Filaggrin Expression in Normal Human Epidermal Keratinocytes

BACKGROUND: Adiponectin, an adipokine secreted from adipocytes, affects energy metabolism and also shows anti-diabetic and anti-inflammatory properties. Recent studies have reported that adiponectin plays a role in regulating skin inflammation. OBJECTIVE: This study aimed to investigate the effect of adiponectin on the expression of filaggrin (FLG) in normal human epidermal keratinocytes (NHEKs). METHODS: NHEKs were serum-starved for 6h before being treated with adiponectin. Afterward, cell viability was assessed by MTT assay. We also treated with calcium, interleukin (IL)-4, and IL-13 to provide positive and negative comparative controls, respectively. Gene mRNA expression was quantified using real time reverse transcription polymerase chain reaction, and protein expression was evaluated using Western blot. To evaluate the relationship among mitogen-activated protein kinases (MAPKs), activator protein 1 (AP-1), and FLG, we also treated cells with inhibitors for MAPKs JNK, p38, and ERK1/2. RESULTS: FLG and FLG-2 mRNA expression in NHEKs significantly increased after treatment with 10 µg/ml adiponectin. Adiponectin also restored FLG and FLG-2 mRNA expression that was otherwise inhibited by treatment with IL-4 and IL-13. Adiponectin induced FLG expression via AP-1 and MAPK signaling. CONCLUSION: Adiponectin positively regulated the expression of FLG and could be useful as a therapeutic agent to control diseases related to disrupted skin barrier function.

Cloning of AP1 Gene from Lonicera macranthoides "Xianglei" and analysis on its Bioinformatics and Space-time expression / 中草药

Objective: To clone the AP1 (Lm-XL-AP1) gene from a Special Variant Varieties of Lonicera macranthoides "Xianglei", and to analyze its bioinformatics and spatio-temporal expression. Methods: Amplifing the full length of Lm-XL-AP1 gene by RACE technique, using bioinformatics method to analyze homology and similarity of the gene, predicting the coding protein and analyzing the various physical and chemical properties. The expression of the gene in different parts of Lonicera macranthoides Special Variant Varieties was detected by fluorescence quantitative PCR (qRT-PCR). Results: The AP1 gene, containing a 729 bp ORF that encoding 242 amino acids, was cloned. And the similarity of the gene compared with the AP1 gene from the MADS-box gene family of Chrysanthemum lavandulifolium up to 80% (Containing a conserved sequence of MADS and K-box). Without transmembrane domain, AP1 was located in cell nucleus. It is expressed in various organs of Lonicera macranthoides Special Variant Varieties. Conclusion: For the first time, the AP1 gene which may be involved in the control of the expression of floral organ was cloned from the total RNA of Lonicera macranthoides Special Variant Varieties.

Effects of resveratrol on cell proliferation in glomerular mesangial cells cultured under high glucose by inhibiting SphK1/AP-1 signal pathway / 中国药理学通报

Aim To observe the expression of FN and TGF-β1 in the glomerular mesangial cells induced by high-glucose after the intervention of resveratrol, and further discuss its influence on SphK1/AP-1 signaling pathway. Methods The rat glomerular mesangial cells induced by high glucose were used to observe the effects of resveratrol on cell proliferation after interven-tion. The survival vitality and proliferation of glomeru-lar mesangial cells were determined by MTT, and then FN, TGF-β1 and SphK1 protein expression were deter-mined by Western blot. Also, AP-1 activity was deter- mined by EMSA assay. Results Resveratrol could obviously inhibit the proliferation of high glucose-in-duced glomerular mesangial cells, lower SphK1 expres-sion, inhibit AP-1 activity and thus inhibit the expres-sion of FN, TGF-β1. Conclusions Resveratrol inhib-its the proliferation of high glucose-induced glomerular mesangial cells, which may be closely related to the in-hibition of SphK1/AP-1 signaling pathway.

TIPE2 sensitizes CDDP to human non-small cell lung cancer cell line NCI-H1975 by suppressing AP-1 / 中国免疫学杂志

Objective:To investigate the chemosensitivity of TIPE2 in enhancing non-small cell lung cancer cell line NCl-H1975 and its mechanisms.Methods:TIPE2 lentiviral vector was transfected into NCI-H1975.IC50 was measured by CCK-8 method after treated with CDDP.Apoptotic cells were detected by Annexin V/FITC and PI apoptosis detection kit.The expression of AP-1 and MDR-1 were measured using Western blot after TIPE2 transfected.The mRNA expression of IL-1,IL-6 and TNF-α were measured using Real-time PCR after TIPE2 transfected combined with CDDP administration.Results:(1) TIPE2 reduces the values of IC50 of NCI-H1975 cells for CDDP(P＜0.001).(2) TIPE2 increases the apoptosis rate of NCI-H1975 cells when treated with CDDP(P＜0.05).(3) TIPE2 significantly reduces the expression of AP-1 and MDR1 in NCI-H1975 cells when treated with CDDP.(4)TIPE2 reduces the mRNA expression of IL-1,IL-6 and TNF-α in NCI-H1975 cells when treated with CDDP(P＜0.01).Conclusion:TIPE2 may increase the chemosensitivity of non-small cell lung cancer cell line NCl-H1975 to CDDP by inhibiting AP-1 protein.

Berberine Suppresses Fibronectin Expression through Inhibition of c-Jun Phosphorylation in Breast Cancer Cells / 한국유방암학회지

PURPOSE: The exact mechanism regulating fibronectin (FN) expression in breast cancer cells has not been fully elucidated. In this study, we investigated the pharmacological mechanism of berberine (BBR) with respect to FN expression in triple-negative breast cancer (TNBC) cells. METHODS: The clinical significance of FN mRNA expression was analyzed using the Kaplan-Meier plotter database (http://kmplot.com/breast). FN mRNA and protein expression levels were analyzed by real-time polymerase chain reaction and western blotting, respectively. RESULTS: Using publicly available clinical data, we observed that high FN expression was associated with poor prognosis in patients with breast cancer. FN mRNA and protein expression was increased in TNBC cells compared with non-TNBC cells. As expected, recombinant human FN significantly induced cell spreading and adhesion in MDA-MB231 TNBC cells. We also investigated the regulatory mechanism underlying FN expression. Basal levels of FN mRNA and protein expression were downregulated by a specific activator protein-1 (AP-1) inhibitor, SR11302. Interestingly, FN expression in TNBC cells was dose-dependently decreased by BBR treatment. The level of c-Jun phosphorylation was also decreased by BBR treatment. CONCLUSION: Our findings demonstrate that FN expression is regulated via an AP-1–dependent mechanism, and that BBR suppresses FN expression in TNBC cells through inhibition of AP-1 activity.

Troglitazone Inhibits Matrix Metalloproteinase-9 Expression and Invasion of Breast Cancer Cell through a Peroxisome Proliferator-Activated Receptor γ-Dependent Mechanism / 한국유방암학회지

PURPOSE: Peroxisome proliferator-activated receptor γ (PPARγ) is involved in the pathology of numerous diseases including atherosclerosis, diabetes, obesity, and cancer. Matrix metalloproteinases (MMPs) play a significant role in tissue remodeling related to various processes such as morphogenesis, angiogenesis, tissue repair, invasion, and metastasis. We investigated the effects of PPARγ on MMP expression and invasion in breast cancer cells. METHODS: MCF-7 cells were cultured and then cell viability was monitored in an MTT assay. Western blotting, gelatin zymography, real-time polymerase chain reaction, and luciferase assays were performed to investigate the effect of the synthetic PPARγ ligand troglitazone on MMP expression. Transcription factor DNA binding was analyzed by electrophoretic mobility shift assay. A Matrigel invasion assay was used to assess the effects of troglitazone on MCF-7 cells. RESULTS: Troglitazone did not affect MCF-7 cell viability. 12-O-tetradecanoylphorbol-13-acetate (TPA) induced MMP-9 expression and invasion in MCF-7 cell. However, these effects were decreased by troglitazone. TPA increased nuclear factor κB and activator protein-1 DNA binding, while troglitazone inhibited these effects. The selective PPARγ antagonist GW9662 reversed MMP-9 inhibition by troglitazone in TPA-treated MCF-7 cells. CONCLUSION: Troglitazone inhibited nuclear factor κB and activator protein-1-mediated MMP-9 expression and invasion of MCF-7 cells through a PPARγ-dependent mechanism.

Individual expression features of GPX2, NQO1 and SQSTM1 transcript variants induced by hydrogen peroxide treatment in HeLa cells

Abstract Pathway activity assessment-based approaches are becoming highly influential in various fields of biology and medicine. However, these approaches mostly rely on analysis of mRNA expression, and total mRNA from a given locus is measured in the majority of cases. Notably, a significant portion of protein-coding genes produces more than one transcript. This biological fact is responsible for significant noise when changes in total mRNA transcription of a single gene are analyzed. The NFE2L2/AP-1 pathway is an attractive target for biomedical applications. To date, there is a lack of data regarding the agreement in expression of even classical target genes of this pathway. In the present paper we analyzed whether transcript variants of GPX2, NQO1 and SQSTM1 were characterized by individual features of expression when HeLa cells were exposed to pro-oxidative stimulation with hydrogen peroxide. We found that all the transcripts (10 in total) appeared to be significantly individually regulated under the conditions tested. We conclude that individual transcripts, rather than total mRNA, are best markers of pathway activation. We also discuss here some biological roles of individual transcript regulation.

Influence of esculentoside A on activation of ERK1/2-AP-1 pathway of glomerular mesangial cell induced by IL-1β / 重庆医学

Objective To observe the influence of serum containing esculentoside A(EsA) on the proliferation of glomerular mesangial cell (GMC) and the activation of ERK1/2-AP-1 pathway of glomerular mesangial cell induced by IL-1β.Methods SD rats were gavaged by different doses of EsA(5,10,20,40 mg/kg) for getting medicated sera.The control group was set (gavage by 0.5sodium carboxymethylcellulose);the EsA medicated serum was used to treat rGMC.The control serum group was set.The influence of EsA medicated serum in each group on rGMC proliferation was detected by MTT;the rGMC was divided into the blank control group,IL-1β single action group,IL-1β+ EsA double action group,IL-1β+ U016 double action group and IL-1β+ U0126 + EsA combined action group,which were synchronized and then cultured for 48 h.Western blot was used to detectthe expression of p-ERK1/2 and AP-1 an the imaging analysis was performed.Results The EsA medicated serum(5-10 mg/kg gavage) inhibited the cellular proliferation(P＜0.05 or P＜0.01);the IL-1β group promoted the expression of p-ERK1/2 and AP-1 in rGMC(P＜ 0.05),after acting on rGMC in the IL-1β+EsA double action group,IL-1β+U0126 double action group and IL-1β+U0126+EsA combined action group,the expression of p-ERK1/2 and AP-1 was decreased(P＜0.05).Conclusion Serum containing EsA (5～10 mg/kg gavage) significantly inhibits the rGMC proliferation;EsA inhibits IL-1β induced rGMC proliferation,its action pathway on ERK1/2-AP-1 is one of mechanisms for inhibiting rGMC proliferation.