Apoptosis of dopaminergic neurons in the nigrostriatal projection plays a crucial role in the pathogenesis of Parkinson's disease (PD). Although the detailed mechanisms responsible for dopaminergic neuron loss are still under investigation, oxidative stress is identified as a major contributor for neuronal apoptosis. In the current study, we studied the effects of MPP(+), a substrate that mimics oxidative stress, on neuron-like PC12 cells and the underlying mechanisms. PC12 cells were cultured and treated by 100 μmol/L MPP(+) for 4, 8, 16, 24 and 48 h, respectively. For drug pretreatment, the PC12 cells were incubated with N-acetyl-l-cysteine (NAC, 5 mmol/L), an antioxidant, SP600125 (20 μmol/L) or PD98059 (100 μmol/L), two pharmacological inhibitors of JNK and ERK1/2, for 1 h before addition of MPP(+). Cell apoptosis was measured by flow cytometry. The mRNA expression of Cu(2+)/Zn(2+)-SOD, GSH-Px, Bcl-2 and Bax was detected by RT-PCR. The protein expression of p-ERK1/2 and p-JNK was determined by Western blotting. Our results showed that MPP(+) exposure could induce substantial PC12 cell apoptosis. The pretreatment of SP600125 or PD98059 could effectively reduce the apoptosis rate by reducing the ratio of Bax/Bcl-2 mRNA levels. MPP(+) exposure also induced high level of reactive oxygen species (ROS), marked by dramatic increase of Cu(2+)/Zn(2+)-SOD and GSH-Px mRNA levels. The elevated ROS was strongly associated with the activation of JNK and ERK1/2 signal pathways after MPP(+) exposure, since the pretreatment of NAC significantly reduced the upregulation of p-JNK and p-ERK1/2. Finally, the pretreatment of SP600125, but not PD98059, alleviated the increase of Cu(2+)/Zn(2+)-SOD and GSH-Px mRNAs induced by MPP(+), suggesting that the activation of the JNK signal pathway, but not the ERK1/2 signal pathway, could, in some degree, antagonize the generation of ROS induced by oxidative stress. In conclusion, our results suggest that JNK and ERK1/2 signal pathways, which are activated via ROS, play a crucial role in neuronal apoptosis induced by oxidative stress.
Animals ; Apoptosis ; drug effects ; Cell Line, Tumor ; PC12 Cells ; Piperidines ; pharmacology ; Pyrazoles ; pharmacology ; Rats ; Reactive Oxygen Species ; metabolism

Neurotensin receptor-1 (NTR1), which can stimulate the intracellular cascade signal pathway, belongs to the large superfamily of G-protein coupled receptors. NTR1 is related to the occurrence and development of several kinds of diseases. In order to screen the inhibitors for the cancers associated with NTR1 protein, we established a CHO (Chinese hamster ovary) cell line in which human neurotensin receptor-1 was highly expressed. The method is to construct the recombinant plasmid which was lysed with the hNTR1 gene and transfect it into CHO cells. After selected with G418, the cell line was evaluated by Western blotting analysis and calcium flux assays. Through the calcium flux assays on FlexStation 3, we got the EC50 value of neurotensin peptide which is the natural NTR1 agonist, and the IC 50 value of SR48692 which is the known NTR1 antagonist. The established human CHO/NTR1 cell line can be used to study the profile of NTR1 biological activity and further screen of NTR1 antagonists and agonists.
Animals ; CHO Cells ; Calcium Signaling ; Cricetinae ; Cricetulus ; Humans ; Pyrazoles ; pharmacology ; Quinolines ; pharmacology ; Receptors, Neurotensin ; antagonists & inhibitors ; genetics ; metabolism ; Transfection

OBJECTIVETo study the effects of celecoxib on the cell proliferation and expression of vascular endothelial growth factor (VEGF) in human nasopharyngeal carcinoma line.

METHODS3-[ 4,5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) test was used to investigate the cell proliferation. Flow cytometry (FCM) was used to analyze the cell cycle arrest. Immunocytochemistry technique was to observe the expression of VEGF.

RESULTSCelecoxib inhibited the growth of nasopharyngeal carcinoma line, the cell number of G0/G1 phase increased from 62.13% to 91.35%, and the cell number of G2/M and S phase decreased from 21.59% to 3.56% and from 16.28% to 5.01%, respectively, cell cycle progression was arrested at G1/S phase. Celecoxib decreased the positive expression of VEGF in HNE-1 cells.

CONCLUSIONSCelecoxib inhibited the proliferation of nasopharyngeal carcinoma significantly and the expression of VEGF.

Celecoxib ; Cell Line, Tumor ; drug effects ; metabolism ; Cell Proliferation ; drug effects ; Humans ; Nasopharyngeal Neoplasms ; metabolism ; pathology ; Pyrazoles ; pharmacology ; Sulfonamides ; pharmacology ; Vascular Endothelial Growth Factor A ; metabolism

AIMTo explore the effects of intrathecal injection of selective cyclooxygenase-1 (COX-1) inhibitor, SC-560, on mechanical allo dynia and spinal ERK protein expression in rats with postoperative pain.

METHODSRats were divided into 4 groups: control group, postoperative pain group, SC-560 group and DMSO group. Mechanical withdrawal threshold (MWT), immunohistochemical and Western blotting technique were used to evaluate mechanical hypersensitivity and the expression of phospho-ERK in the spinal cord, respectively.

RESULTS(1) Behavior test rats developed allodynia 1 h after operation and SC-560 100 microg administrated intrathecally demonstrated a significant reduction in postoperative hypersensitivity. (2) Immunohistochemical staining Phospho-ERK positive neurons in the rat superficial spinal dorsal horn increased significantly 1 h after incision compared with that of non-incision group. Intrathecal administration of SC-560 preoperatively could significantly reduce the number of phospho-ERK positive neurons. (3) Western blot expression of phospho-ERK1/2 protein in the lumbar spinal cord increased significantly 1 h after incision and decreased by intrathecal injection of SC-560.

CONCLUSIONSC-560 administrated intrathecally can inhibit mechanical hypersensitivity induced by postoperative pain in rats and this anti-allodynic process may mediated by spinal ERK.

Animals ; Cyclooxygenase Inhibitors ; pharmacology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Male ; Pain Measurement ; drug effects ; Pain, Postoperative ; metabolism ; Pyrazoles ; pharmacology ; Rats ; Rats, Wistar ; Spinal Cord ; drug effects ; metabolism

This study was conducted to evaluate the growth and NAG-1 gene expression effected by Non-steroidal anti-inflammatory drug (NSAID) on colon cancer cell lines in vitro. The proliferation of colon cancer cells were determined by MTT assay and COX-2 protein expression were detected by Western blot. Total RNA was isolated from three kinds of colon cancer cell lines; the expressions of NAG-1 mRNA in the cells treated with or without NSAIDs were assessed by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assay. Celecoxib, meloxicam and aspirin were able to inhibit the growth of HT-29, SW480 and LS174-T cells in dose-dependent manner. COX-2 protein expressed in HT-29 and LS174-T, but not in SW480 cells. All of colon cancer cells expressed NAG-1 gene and the level of LS174-T was lower than that of the other two cell lines. NAG-1 expression was increased by treatment with some NSAIDs in all three kinds of colon cancer cells. NSAIDs were able to potentially inhibit the growth of colon cell lines. Induction of NAG-1 gene expression by NSAID was not consistent with COX-2 expression.
Anti-Inflammatory Agents, Non-Steroidal ; pharmacology ; Antineoplastic Agents ; pharmacology ; Aspirin ; pharmacology ; Celecoxib ; Cell Proliferation ; drug effects ; Cyclooxygenase 2 ; metabolism ; Gene Expression Regulation, Neoplastic ; HT29 Cells ; Humans ; Neoplasm Proteins ; metabolism ; Pyrazoles ; pharmacology ; RNA, Messenger ; metabolism ; Sulfonamides ; pharmacology ; Thiazines ; pharmacology ; Thiazoles ; pharmacology

The aim of this study was to investigate the effects of Celecoxib on the proliferation, apoptosis, cell cycle and CD117 expression of K562 cells, and to explore its synergistic effect with IFN-alpha. K562 cells were treated with IFN-alpha, Celecoxib and combination of Celecoxib with IFN-alpha at different concentrations. The inhibitory effect of Celecoxib and IFN-alpha on cell proliferation was detected with MTT assay, the cell apoptosis, cell cycle and CD117 expression were determined by morphology observation and flow cytometry. The results showed that the Celecoxib inhibited proliferation of K562 cells in concentration-dependent manner (r=-0.91). After culture of K562 cells for 72 hours, the rates of K562 cell proliferation in control group, IFN-alpha group, Celecoxib group and IFN-alpha-combined Celecoxib group were (96.1+/-0.5)%, (90.2+/-0.4)%, (57.2+/-0.9)% and (21.9+/-0.3)% respectively. The cell apoptosis rates in 4 groups were (5.5+/-0.8)%, (6.3+/-0.6)%, (26.4+/-3.9)% and (57.3+/-4.5)% respectively. The CD117 expression rates in 4 groups were 54.7%, 10.5%, 36.3% and 7.3% respectively. Combination of Celecoxib with IFN-alpha might block K562 cells in G0/G1 phase. In conclusion, Celecoxib and IFN-alpha both may inhibit K562 cell proliferation, induce apoptosis, reduce CD117 expression and produce G0/G1 phase block to various degree and the two drugs have a synergistic effect.
Apoptosis ; drug effects ; Celecoxib ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Humans ; Interferon-alpha ; pharmacology ; K562 Cells ; Proto-Oncogene Proteins c-kit ; metabolism ; Pyrazoles ; pharmacology ; Sulfonamides ; pharmacology

OBJECTIVETo explore the antagonizing effect of celecoxib against the cytotoxicity of carboplatin in human esophageal cancer cells.

METHODSThe cell viability of cisplatin-resistant cell line EC109/CDDP and its parental cell line EC109 exposed to carboplatin alone or carboplatin plus celecoxib was determined by MTT assay. The expression of CTR1, caspase-3 activation and PARP cleavage in the exposed cells were examined by Western blotting. Caspase-3 activity and cell apoptosis after the exposure were detected with Caspase-3/7 assay and flow cytometry, respectively. The effect of celecoxib on carboplatin accumulation in the cells was measured using inductively coupled plasma mass spectrometry (ICP-MS).

RESULTSCelecoxib treatment significantly increased the IC50 of carboplatin, suppressed carboplatin-induced caspase-3 and PARP cleavage and caspase-3 activity in EC109 and EC109/CDDP cells. Celecoxib also inhibited carboplatin-induced apoptosis and suppressed intracellular carboplatin accumulation in both cell lines. A combined exposure to celecoxib and carboplatin did not cause significant changes in the protein expression of CTR1.

CONCLUSIONCelecoxib antagonizes the cytotoxic effect of carboplatin and inhibits carboplatin-induced apoptosis in human esophageal cancer cells by reducing intracellular carboplatin accumulation.

Apoptosis ; Blotting, Western ; Carboplatin ; antagonists & inhibitors ; Caspase 3 ; metabolism ; Celecoxib ; Cell Line, Tumor ; drug effects ; Cell Survival ; Drug Interactions ; Esophageal Neoplasms ; metabolism ; pathology ; Humans ; Pyrazoles ; pharmacology ; Sulfonamides ; pharmacology

This study was aimed to investigate the influence and significance of celecoxib (specific inhibitor of cyclooxygenase-2) on mRNA expressions of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (b-FGF), transforming growth factor β (TGF-β) in acute leukemia cells. The expressions of VEGF, b-FGF, TGF-β mRNA were measured by RT-PCR in acute leukemia cells treated with celecoxib (80 µmol/L, for 48 h) or with PBS. The results showed that the obvious expressions of VEGF, b-FGF, TGF-β mRNA were observed in acute leukemia cells. By using Pearson correlation analysis, there was positive correlation between VEGF mRNA and b-FGF mRNA expressions (r = 0.559, P = 0.001), and negative correlation between VEGF and TGF-β mRNA expressions (r = -0.4, P = 0.029). Expression levels of VEGF, b-FGF, TGF-β mRNA in experimental group were lower than that in control group (P < 0.01). It is concluded that COX-2 inhibitor celecoxib can inhabit vascular endothelial growth through down-regulating the mRNA expression of VEGF, b-FGF and TGF-β in acute leukemia cells. COX-2 inhibitor may offer supplemental effect for treating acute leukemia.
Adult ; Celecoxib ; Cyclooxygenase 2 Inhibitors ; pharmacology ; Female ; Fibroblast Growth Factor 2 ; metabolism ; Humans ; Leukemia ; drug therapy ; metabolism ; Male ; Pyrazoles ; pharmacology ; RNA, Messenger ; genetics ; Signal Transduction ; Sulfonamides ; pharmacology ; Transforming Growth Factor beta ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism

This study was aimed to investigate the effect of COX-2 inhibitor celecoxib on proliferation, apoptosis of human acute myeloid leukemia cell line HL-60 and its mechanism. HL-60 cells were cultured with different concentrations of celecoxib for 24 h. Cell proliferation was analyzed by CCK-8 assay, cell apoptosis and cell cycle distribution were detected by flow cytometry. Cyclin D1, cyclin E1 and COX-2 mRNA expressions were determined by RT-PCR. The results showed that after the HL-60 cells were treated with different concentrations of celecoxib for 24 h, the cell growth was significantly inhibited in a dose-dependent manner(r = 0.955), IC50 was 63.037 µmol/L of celecoxib. Celecoxib could effectively induce apoptosis in HL-60 cells also in dose-dependent manner(r = 0.988), blocked the HL-60 cells in the G0/G1 phase. The expression of cyclin D1, cyclin E1 and COX-2 mRNA were downregulated. It is concluded that celecoxib can inhibit the proliferation of HL-60 cells in dose-dependent manner, celecoxib causes cell G0/G1 arrest and induces cell apoptosis possibly through down-regulation of the cyclin D1 and cyclin E1 expression, and down-regulation of COX-2 expression respectively.
Apoptosis ; drug effects ; Celecoxib ; Cell Proliferation ; drug effects ; Cyclin D1 ; metabolism ; Cyclin E ; metabolism ; Cyclooxygenase 2 ; metabolism ; Cyclooxygenase 2 Inhibitors ; pharmacology ; Gene Expression Regulation, Leukemic ; HL-60 Cells ; Humans ; Oncogene Proteins ; metabolism ; Pyrazoles ; pharmacology ; Sulfonamides ; pharmacology

OBJECTIVETo investigate whether cyclooxygenase-2 (COX-2) and heme oxygenase-1 (HO-1) are involved in the bradykinin-induced delayed protection.

METHODSCardiac contractility, lactate dehydrogenase (LDH) and infarct area were analyzed in isolated rat hearts undergoing ischemia-reperfusion injury induced by Langendorff method.

RESULTConscious rats received bradykinin (40 microg/kg), and the isolated hearts were subjected to 30 min of regional ischemia and 120 min of reperfusion 24 h later. Bradykinin pretreatment would improve post-ischemic performance, and reduced the release of LDH and infarct size. COX-2 inhibitor celecoxib (3 mg/kg) abolished bradykinin-induced protection, leading to poorer myocardial performance, release of more LDH and larger infarct sizes. Administration of HO-1 inhibitor ZnPP IX(20 microg/kg) before bradykinin partially abrogated the delayed protection. Pretreatment with the mitochondrial ATP sensitive potassium channel(mitoK(ATP) antagonist 5-HD before or 24 h after bradykinin administration also abolished the effect of protection.

CONCLUSIONThe results indicate that activation of HO-1 and COX-2 might be involved in the delayed cardioprotection evoked by bradykinin, and mitoK(ATP) channel may serve as both a trigger and a mediator in the cardioprotection.

Animals ; Bradykinin ; pharmacology ; Celecoxib ; Cyclooxygenase 2 ; metabolism ; Cyclooxygenase Inhibitors ; pharmacology ; Heme Oxygenase-1 ; metabolism ; In Vitro Techniques ; Ischemic Preconditioning, Myocardial ; methods ; Male ; Myocardial Reperfusion Injury ; enzymology ; prevention & control ; Potassium Channels ; physiology ; Pyrazoles ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Sulfonamides ; pharmacology