ABSTRACT
ObjectiveTo observe the glucose-lowering， insulin resistance-improving， and anti-inflammatory effects of flavonoids from mulberry leaves （FML） and explore their underlying mechanism. MethodMale db/db mice aged 6-7 weeks were randomly divided into a model group， a high-dose FML group （1.00 g·kg·d-1）， and a low-dose FML group （0.50 g·kg-1·d-1）. C57BL mice of the same age were assigned to the normal group. After six weeks of intervention， fasting blood glucose （FBG）， serum fasting insulin levels （Fins）， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， free fatty acid （FFA）， blood creatinine （SCr）， blood urea nitrogen （BUN）， and aspartate aminotransferase （AST） levels were measured， and the homeostasis model assessment of insulin resistance （HOMA-IR） was calculated. Superoxide dismutase （SOD）， glutathione peroxidase （GSH-Px）， and catalase activities in the liver were measured. Morphological changes in the liver were assessed by hematoxylin-eosin （HE） staining. The protein expression of cyclooxygenase-2 （COX-2）， inducible nitric oxide synthase （iNOS）， and nuclear factor-κB （NF-κB） in the liver was detected by Western blot. ResultCompared with the model group， the high-dose and low-dose FML groups showed significant reductions in FBG， Fins， HOMA-IR， IL-6， TNF-α， and FFA levels （P<0.05， P<0.01）， and increased levels of SOD， GSH-Px， and catalase in the liver （P<0.05， P<0.01）. HE staining of the liver in the FML groups showed improved arrangement of hepatocytes， reduced inflammatory cell infiltration， and alleviated cellular steatosis compared with the model group. The protein expression of COX-2， iNOS， and NF-κB in the liver significantly decreased in the FML groups as compared with that in the model group （P<0.05， P<0.01）. ConclusionFML have glucose-lowering and insulin resistance-improving effect， which may be attributed to their regulation of the NF-κB pathway in the liver of diabetic mice， leading to the suppression of the release of COX-2， iNOS， and inflammatory cytokines， thereby improving the inflammatory state.
ABSTRACT
ObjectiveTo explore the underlying mechanism of Tripterygium wilfordii polyglycoside tablets （TWPT） in the prevention and treatment of kidney injury in diabetic nephropathy （DN） through the nuclear factor of activated T-cells 2（NFAT2）/cyclooxygenase-2（COX-2） pathway. MethodForty-two male SD rats of SPF grade were selected and randomly divided into a normal group （n=8） and an experimental group （n=34） after one week of adaptive feeding. The rats in the normal group were fed conventionally. The DN model was established in rats of the experimental group by intraperitoneal injection of streptozotocin （STZ） following one week of feeding on a high-fat and high-glucose diet. After the death and failure cases during modeling were eliminated， the remaining 24 model rats were randomly divided into model group， valsartan （8.33 mg·kg-1·d-1） group， and TWPT （5 mg·kg-1·d-1） group. Rats in normal group and model group were given equal amounts of normal saline by gavage. After six weeks， body weight was measured and urine samples were collected. Blood samples were collected from the abdominal aorta， and then the rats were sacrificed for sampling. Biochemical indicators， such as serum blood urea nitrogen （BUN）， serum creatinine （SCr）， alanine aminotransferase （ALT）， blood lipid， blood glucose， and 24-hour urine total protein （24 h UTP）， were determined. Hematoxylin-eosin （HE） staining and Masson staining were used to observe the pathology of the kidney. Enzyme-linked immunosorbent assay （ELISA） was used to detect NFAT2 and COX-2 expression levels in the serum. Western blot and Real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）were adopted to detect NFAT2， COX-2 protein and mRNA expression in kidney tissues， respectively. ResultCompared with the normal group， the model group showed elevated 24 h UTP， BUN， SCr， CHO， TG， and FBG， increased serum NFAT2 and COX-2 production and expression （P<0.01）， and elevated protein and mRNA expression of NFAT2 and COX-2 in kidney tissues （P<0.01）. In addition， the pathology of the kidney showed enlarged glomeruli， mild proliferation of mesangial cells， and widened mesangial stroma. Compared with the model group， the TWPT group showed decreased 24 h UTP， BUN， SCr， CHO， TG， and FBG （P<0.05，P<0.01）， basically normal glomerular morphology， decreased expression of serum NFAT2 and COX-2 （P<0.01）， and down-regulated protein and mRNA expression of NFAT2 and COX-2 in kidney tissues （P<0.01）. ConclusionTWPT can alleviate 24 h UTP in DN model rats， protect renal function， and improve renal pathology， and its mechanism of action may be related to the down-regulation of NFAT2/COX-2 expression in the serum and kidney tissues.
ABSTRACT
OBJECTIVE@#To observe the effects of moxibustion at "Baihui" (GV 20) and "Dazhui" (GV 14) at different time points on the serum level of β-endorphin (β-EP), substance P (SP) and expression of interleukin-1β (IL-1β) and cyclooxygenase-2 (COX-2) protein in brainstem in rats with migraine, and to explore the effect and mechanism of moxibustion in preventing and treating migraine.@*METHODS@#Forty male SD rats were randomly divided into a blank group, a model group, a prevention+treatment (PT) group and a treatment group, 10 rats in each group. Except the blank group, the rats in the remaining groups were injected with nitroglycerin subcutaneously to prepare migraine model. The rats in the PT group were treated with moxibustion 7 days before modeling (once a day) and 30 min after modeling, while the rats in the treatment group were treated with moxibustion 30 min after modeling. The "Baihui" (GV 20) and "Dazhui" (GV 14) were taken for 30 minutes each time. The behavioral scores in each group were observed before and after modeling. After intervention, ELISA method was used to detect the serum level of β-EP and SP; the immunohistochemistry method was used to detect the number of positive cells of IL-1β in brainstem; the Western blot method was used to detect the expression of COX-2 protein in brainstem.@*RESULTS@#Compared with the blank group, the behavioral scores in the model group were increased 0-30 min, 60-90 min and 90-120 min after modeling (P<0.01); compared with the model group, in the treatment group and the PT group, the behavioral scores were decreased 60-90 min and 90-120 min after modeling (P<0.01). Compared with the blank group, in the model group, the serum level of β-EP was decreased (P<0.01), while the serum level of SP, the number of positive cells of IL-1β in brainstem and the expression of COX-2 protein were increased (P<0.01). Compared with the model group, in the PT group and and the treatment group, the serum level of β-EP was increased (P<0.01), while the serum level of SP, the number of positive cells of IL-1β and the expression of COX-2 protein in brainstem were decreased (P<0.01, P<0.05). Compared with the treatment group, in the PT group, the serum level of β-EP was increased and COX-2 protein expression was decreased (P<0.05).@*CONCLUSION@#Moxibustion could effectively relieve migraine. The mechanism may be related to reduce the serum level of SP, IL-1β and COX-2 protein expression in brainstem, and increase the serum level of β-EP, and the optimal effect is observed in the PT group.
Subject(s)
Rats , Male , Animals , Moxibustion , Rats, Sprague-Dawley , Cyclooxygenase 2 , beta-Endorphin , Substance P , Interleukin-1beta , Migraine Disorders , Brain StemABSTRACT
Xiaoer-Feire-Kechuan (XFK) is an 11-herb Chinese medicine formula to treat cough and pulmonary inflammation.The complicated composition rendered its chemical analysis and effective-component elucidation.In this study,we combined quantitative analysis and bioactivity test to reveal the anti-inflammatory constituents of XFK.First,UPLC-DAD and UHPLC/Q-Orbitrap-MS methods were estab-lished and validated to quantify 35 analytes (covering 9 out of 11 herbs) in different XFK formulations.Parallel reaction monitoring mode built in Q-Orbitrap-MS was used to improve the sensitivity and selectivity.Then,anti-inflammatory activities of the 35 analytes were analyzed using in vitro COX-2 inhibition assay.Finally,major analytes forsythosides H,I,A (8-10),and baicalin (15) (total contents varied from 21.79 to 91.20 mg/dose in different formulations) with significant activities (inhibitory rate ≥ 80％) were proposed as the anti-inflammatory constituents of XFK.The present study provided an effective strategy to discover effective constituents of multi-herb formulas.
ABSTRACT
Objective: Drug-resistance and metastasis are major reasons for the high mortality of ovarian cancer (OC) patients. Cyclooxygenase-2 (COX-2) plays a critical role in OC development. This study was designed to evaluate the effects of COX-2 on migration and cisplatin (cis-dichloro diammine platinum, CDDP) resistance of OC cells and explore its related mechanisms. Methods: Cell counting kit-8 (CCK-8) assay was used to detect the cytotoxicity effects of celecoxib (CXB) and CDDP on SKOV3 and ES2 cells. The effect of COX-2 on migration was evaluated via the healing test. Western blot and real-time quantitative polymerase chain reaction (qPCR) were used to analyze E-cadherin, vimentin, Snail, and Slug levels. Results: COX-2 promoted drug-resistance and cell migration. CXB inhibited these effects. The combination of CDDP and CXB increased tumor cell sensitivity, reduced the amount of CDDP required, and shortened treatment administration time. COX-2 upregulation increased the expression of Snail and Slug, resulting in E-cadherin expression downregulation and vimentin upregulation. Conclusions: COX-2 promotes cancer cell migration and CDDP resistance and may serve as a potential target for curing OC.
ABSTRACT
Objective To investigate the expression of microRNA-1290 in pancreatic cancer and its role in invasion and metastasis of pancreatic cancer.Methods The expression of microRNA-1290 in pancreatic cancer tissue microarray and pancreatic cancer cell lines (AsPC-1,BxPC-3,Capan-2,Panc-1,and MIA PaCa-2) were detected by immunohistochemistry and QT-PCR.The pancreatic cancer cell lines Panc-1 and MIA PaCa-2 in logarithmic growth phase were treated with microRNA-1290 inhibitor,and the invasion and metastasis ability of pancreatic cancer cells were detected by Transwell and wound healing asssay.Western Blot was used to detect the expression of invasion and metastasis-associated proteins cyclooxygenase 2 (COX-2) and matrix metalloproteinase 2(MMP-2) in pancreatic cancer cell lines.Results (1) The expression of microRNA-1290 in pancreatic cancer tissues was significantly higher than that in normal pancreatic tissues and adjacent tissues (P ＜ 0.05).(2) Compared with pancreatic normal epithelial cells (HPDE),the expression of microRNA-1290 was significantly higher in different pancreatic cancer cell lines (P ＜ 0.05).The expression level of MicroRNA-1290 in Panc-1 and MIAPaCa-2 pancreatic cancer cells was significantly higher than that in other pancreatic cancer cell lines (P ＜ 0.05).(3) The number of invasive and metastatic cells was significantly decreased after treatment with microRNA-1290 inhibitor (P ＜0.05).(4) The expression of MMP-2 and COX-2 were decreased in Panc-1 and MIAPaCa-2 pancreatic cancer cells treated with MicroRNA-1290 inhibitor.Conclusion The expression of MMP-2 and COX-2 may be involved in the invasion and metastasis of pancreatic cancer cell by regulating the expression of microRNA-1290 in pancreatic cancer.
ABSTRACT
BACKGROUND: The trigeminal nucleus caudalis (Vc) is a primary central site for trigeminal transmitting. Noxious stimulation of the trigeminal nociceptors alters the central synaptic releases and neural expression of some inflammatory and trophic agents. Orexin-A and the orexin 1 receptor (OX1R) are expressed in pain pathways including trigeminal pain transmission. However, the the mechanism(s) underling orexin-A effects on trigeminal pain modulation have not been fully clarified. METHODS: Trigeminal pain was induced by subcutaneous injection of capsaicin in the upper lip in rats. The effect of trigeminal pain on cyclooxygenase-2 (COX-2) and brain-derived neurotrophic factor (BDNF) expression in the Vc of animals was determined by immunofluorescence. Subsequently, OX1R agonist (orexin-A) and antagonist (SB-334867-A) was administrated in the Vc to investigate the possible roles of the Vc OX1R on changes in COX-2 and BDNF levels following pain induction. RESULTS: The data indicated an increase in COX-2 and decrease in BDNF immuno-reactivity in the Vc of capsaicin, and capsaicin- pretreated with SB-334867-A (80 nM), groups of rat. However, the effect of capsaicin on COX-2 and BDNF expressions was reversed by a Vc microinjection of orexin-A (100 pM). CONCLUSIONS: Overall, the present data reveals that orexin-A can attenuate capsaicin-induced trigeminal pain through the modulation of pain effects on COX-2 and BDNF expressions in the Vc of rats.
Subject(s)
Animals , Rats , Brain-Derived Neurotrophic Factor , Capsaicin , Cyclooxygenase 2 , Facial Pain , Fluorescent Antibody Technique , Injections, Subcutaneous , Lip , Microinjections , Nociceptors , Orexin Receptor Antagonists , Orexins , Pain Measurement , Pain Perception , Trigeminal Caudal Nucleus , Trigeminal Neuralgia , Trigeminal NucleiABSTRACT
Objective To investigate the effect of docosahexaenoic acid (DHA) combined with cyclooxygenase-2 (COX-2) selective inhibitor NS-398 on the apoptosis of cholangiocarcinoma QBC939 cells and the mechanism.Methods In vitro,cholangiocarcinoma QBC939 cells were treated with 0,15,30,45,60 and 75 μg/ml DHA with 0,25,50,100,150 and 200 μmol/L NS-398,respectively.The absorbances of the QBC939 cells were measured by CCK8 and its growth inhibition ratios were analyzed.Flow cytometry was applied to detect cell apoptosis.The level of β-catenin and COX-2 mRNA and protein were measured by real-time PCR,immunocytochemistry and enzyme-linked immunoadsordent assay,respectively.Results DHA combined with NS-398 could significantly suppress the growth of QBC939 cells (P ＜ 0.05).When the concentration of DHA went up to 45 μg/ml and NS-398 was 100 μmol/L,the relative growth inhibition rate of QBC939 cells was 90.0％.If the concentrations were increased,the result showed no significant differences.Furthermore,flow cytometry analysis indicated that DHA combined with NS-398 could induce QBC939 cells apoptosis at the early stage,and the apoptosis rate was significantly different between the experimental and control groups (P ＜ 0.01).Real-time PCR showed low β-catenin and COX-2 expression in QBC939 cells disposed by DHA combined with NS-398,and their expression were significantly different between the experimental and control groups (P ＜ 0.01).Immunocytochemistry and ELISA demonstrated that DHA combined with NS-398 could decrease β-catenin and COX-2 protein expression in QBC939 cells.Conclusion DHA combined with NS-398 induced apoptosis and inhibited proliferation of cholangiocarcinoma cells QBC939 in vitro through targeting β-catenin and COX-2.
ABSTRACT
AIM To study the effects and action mechnism of Xiaoding Ointment (Pyrolusite,Catechu,Rhei Radix et Rhizoma,etc.) on rabbits' fracture healing in terms of cyclooxygenase-2 (COX-2),prostaglandin E2 (PGE2),cyclic adenosine monophosphate (cAMP) expressions at different time points.METHODS One hundred and twenty-eight New Zealand white rabbits were randomly divided into blank group,model group,Qingpeng Ointment (Oxytropis Falcatae Herba,Rhei lhasaense Radix et Rhizoma,Terminalia chebula Fructus,etc.) group and Xiaoding Ointment group.All the other groups,except the blank group,were made with ulna 3 mm bone defect,after which external fixation was applied to both the blank group and the model group.On the 3rd,7th,14th and 28th days after the medications,eight rabbits randomly selected from various groups had their callus morphopathology changes observed under optical microscope,their callus tissue COX-2 mRNA expression levels were detected by realtime fluorescence quantitative polymerase chain reaction (qRT-PCR),and their callus tissue PGE2 and cAMP protein expressions were determined by immunohistochemistry.RESULTS Compared with the model group and the Qingpeng Ointment group,the Xiaoding Ointment group exhibited significantly better formation of callus and collagen fibers.The mRNA expression of COX-2,and the protein expressions of PGE2 and cAMP in the Xiaoding Ointment group were remarkably enhanced as revealed on the 7th and 14th days' postoperative check (P ＜ 0.05),and the peak values arrived around the 14th day after the operation.CONCLUSION Xiaoding Ointment's obvious effect on promoting fracture healing may associate with its impact on COX-2/PGE2/cAMP signaling pathway.
ABSTRACT
Objective • To investigate the effects of liraglutide on glucose induced expression of miRNA-146b-3p, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and cyclooxygenase-2 (COX-2) in human umbilical vein endothelial cells (HUVECs). Methods • HUVECs were grown in the medium with glucose of high concentration (25 mmol/L) or normal concentration (7 mmol/L) for 24 h, then stimulated with liraglutide. Quantitative polymerase chain reaction (qPCR) was performed to detect the expression of miR-146b-3p, IL-6, TNF-α and COX-2. The expression of IL-6, TNF-α and COX-2 were detected after HUVECs were transfected with anti-miR-146b-3p. Results • The expression of miR-146b-3p was decreased in high glucose induced cells, while the expression of IL-6, TNF-α and COX-2 were increased. Silenced expression of miR-146b-3p increased the expression of IL-6, TNF-α and COX-2. Liraglutide increased the expression of miR-146b-3p and decreased the expression of IL-6, TNF-α and COX-2 in high glucose induced cells. Conclusion • Liraglutide may relieve inflammation and improve vascular endothelial function in hyperglycemia condition through regulating miR-146b-3p to decrease expression of IL-6, TNF-α and COX-2.
ABSTRACT
Objective To observe the effects of capsaicin on PGE2 concentration of IL-1β-induced human large cell carcinoma NCI-H460 cells,and further observe its effect on COX-2 and mPGES-1 so as to explore the possible mechanisms against non-small cell lung cancer.Methods NCI-H460 cells were cultured in vitro ;the effect of capsaicin in inhibiting NCI-H460 cells proliferation was observed.The 50% inhibitory concentration (IC50 ) was measured by MTT assay.IL-1βstimulation method was used to construct inflammation model,and the effects of capsaicin on COX-2 activity and PGE2 concentration in NCI-H460 cells were measured by ELISA.The effects of capsaicin on COX-2 and mPGES-1 protein level in NCI-H460 cells were analyzed by Western blot;the effects of capsaicin on COX-2 mRNA and mPGES-1 mRNA expressions in NCI-H460 cells were analyzed by Real-time PCR. Results MTT assay results showed that the growth of NCI-H460 cells treated with capsaicin was significantly inhibited compared with the control group (P <0.05 or P <0.01 ).Capsaicin could significantly decrease COX-2 activity and PGE2 concentration in NCI-H460 cells,and significantly decrease COX-2,mPGES-1 protein levels as well as COX-2,mPGES-1 mRNA expressions in NCI-H460 cells in a dose-dependent manner compared with the control group (P < 0.05 ).Conclusion Capsaicin inhibits the release of PGE2 by downregulating COX-2 and mPGES-1 mRNA expressions in NCI-H460 cells,which may be one mechanism of its effect against non-small cell lung cancer.
ABSTRACT
Objective To evaluate the role of EP_2 in synaptic transmission in dentate gyrus of hippocampus. Methods Field excitatory post-synaptic potentials (fEPSP) were recorded at the perforated path-granule neurons in dentate gyrus in vitro. Results ① Butaprost, an agonist of EP_2, enhanced the synaptic transmission in dentate gyrus and decreased the paired-pulse ratio, and these effects were reversed by bath application of AH6809 (EP_2 antagonist). ② Application of Forskolin alone or with AH6809 elevated the slope of fEPSP. ③ The Butaprost-induced responses were mediated via PKA, ERK and IP_3 signal pathways. Conclusion Multiple signal pathways were involved in the EP_2 activation-mediated enhancement of synaptic transmission.
ABSTRACT
In the present study, neuroprotective property of celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, and its underlying mechanism were examined in the animal model of kainic acid (KA)-induced excitotoxicity. KA, administered intracerebroventricularly (i.c.v.), induced marked neuronal cell death with concurrent microglial activation and subsequent induction of inducible nitric oxide synthase (iNOS) in the hippocampus. Histopathological analysis demonstrated that celecoxib (100 mg/kg), pre-treated 1 hr before or post-treated 2 hr after KA i.c.v. injection, significantly attenuated KA-induced death of pyramidal neurons in CA3 region. Celecoxib obviously suppressed KA-induced microglial activation and subsequent iNOS expression. KA- induced phosphorylation of c-Jun N-terminal kinases (JNK) was attenuated with celecoxib treatments. The results of the present study demonstrate that suppression of JNK phosphorylation by celecoxib contributes to its neuroprotective action against KA-induced excitotoxicity suggesting that celecoxib may be a potentially valuable in the treatment of acute brain pathologies associated with excitotoxic neuronal damage such as epilepsy, stroke, and traumatic brain injury.
Subject(s)
Brain , Brain Injuries , Cell Death , Cyclooxygenase 2 , Epilepsy , Hippocampus , JNK Mitogen-Activated Protein Kinases , Kainic Acid , Microglia , Models, Animal , Neurons , Nitric Oxide Synthase Type II , Phosphorylation , Phosphotransferases , Pyrazoles , Stroke , Sulfonamides , CelecoxibABSTRACT
Chemoprevention is currently regarded as one of the most promising avenues of cancer control. In the search for chemopreventive dietary plants and phytochemicals, the author has explored anti-tumor promotimg phytochemicals of vegetables and fruits in several Asian countries, using an inhibition test of tumor promoter-induced Epstein-Barr virus (EBV) activation. Extensive <i>in vitro</i> screening tests have found several dietary plants from subtropical zones to possess high potential. In particular, plants in families commonly ingested for purposes other than their nutritive value (<i>i.e.</i> as flavors, condiments, and occasionally traditional medicines) were shown to contain potent anti-tumor promoters. Of more than 50 <i>in vitro</i> anti-tumor promoters identified thus far, cancer preventive properties of 4 compounds from zingiberaceous (1′-acetoxychavicol acetate and zerumbone) and rutaceous (auraptene and nobiletin) plants have been further studied. The results of animal model experiments as well as modes of action, including anti-inflammation associated activities, are described. The present status of chemoprevention with food phytochemicals is also discussed.<br>
ABSTRACT
BACKGROUND/AIMS: Cyclooxygenase-2 (COX-2) inhibitors reportedly inhibit the growth of hepatocellular carcinoma (HCC) via caspase-dependent or caspase-independent apoptosis, which is due to COX-2 being associated with hepatocarcinogenesis. Survivin is highly expressed in most human cancers, but the mechanism regulating survivin expression remains unclear. We investigated the regulatory expression of survivin in selective-COX-2-inhibitor-induced growth inhibition of hepatoma cells. METHODS: After treatment with NS-398 (a selective COX-2 inhibitor) at various concentrations (10, 50, 100, 150, and 200 micrometer), the growth inhibition of Hep3B hepatoma cells was assessed by an MTT cell-viability assay, DNA fragmentation gel analysis, and flow cytometry. The expression of survivin transcript was analyzed by reverse-transcription polymerase chain reactions. RESULTS: NS-398 inhibited the growth of hepatoma cells by an amount dependent on the concentration and the time since treatment. Apoptotic DNA ladder and flow-cytometry shifting to the sub-G1 phase were revealed in NS-398-induced growth inhibition of hepatoma cells. NS-398 suppressed the expression of the survivin gene in a concentration- and time-dependent manner. CONCLUSIONS: Survivin was down-regulated in the growth inhibition of hepatoma cells induced by a selective COX-2 inhibitor, NS-398, in a concentration- and time-dependent manner. These results suggest the therapeutic inhibition of COX-2 via suppression of survivin in HCC.
Subject(s)
Humans , Carcinoma, Hepatocellular/enzymology , Cell Line, Tumor , Cell Proliferation/drug effects , Cyclooxygenase 2 Inhibitors/chemistry , G1 Phase , Liver Neoplasms/enzymology , Microtubule-Associated Proteins/antagonists & inhibitors , Neoplasm Proteins/antagonists & inhibitors , Nitrobenzenes/chemistry , Reverse Transcriptase Polymerase Chain Reaction , Sulfonamides/chemistry , Time FactorsABSTRACT
0bjective:To study the proliferative and apoptotic effects of NS398,a selective COX-2 inhibitor,on renal carcinoma cell line 786-O in vitro. Methods:786-O cells were treated with different concentrations of NS398 for24,48,72 and 96 h.The proliferation of 786-O cells was studied by MTT assay.Immuno cytochemistry was used to detect the expressions of COX-2 . The expression of COX-2 mRNA was analyzed by reverse transcription-polymerase chain raction(RT-PCR).Flow cytometric analysis was used to detect the apoptosis status of 786-O cells. Results:NS398 resulted in significant antiproliferative effects on 786-O cells in dose and time dependent manner. Immunocytochemistry showed the expressions of COX-2 were significantly inhibited by NS398. RT-PCR showed the expressions of COX-2 were significantly inhibited by NS398. Apoptosis rate were 31.5%?2.1% and 14.3%?1.4%,respectively in the 786-O cells treated with NS398 in different concentrations of 180 ?umol/L and 30 ?mol/L,which was significantly higher than in the control group 2.1%?0.4%. Conclusion:NS398 could effectively suppress the growth of 786-O cells and induce apoptosis,the mechanism of which probably relates to its inhabited expression of COX-2.
ABSTRACT
OBJECTIVE: Kainic acid(KA) enhances the expression of nitric oxide synthase, increases nitric oxide(NO), and thus evokes epileptic convulsion, which results in neuronal damage in the rat brain. NO may stimulate cyclooxygenase type-2 (COX-2) activity, thus producing seizure and neuronal injury, but it has also been reported that KA-induced seizure and neurodegeneration are aggravated on decreasing the COX-2 level. This study was undertaken to investigate whether the suppression of NO using the NOS inhibitor, N-nitro-L-arginine methyl ester(L-NAME), suppresses or enhances the activity of COX-2. METHODS: Silver impregnation and COX-2 immunohistochemical staining were used to localize related pathophysiological processes in the rat forebrain following KA-induced epileptic convulsion and L-NAME pretreatment. Post-injection survival of the rat was 1, 2, 3days and 2months, respectively. RESULTS: After the systemic administration of KA in rats, neurodegeneration increased with time in the cornu ammonis (CA) 3, CA 1 and amygdala, as confirmed by silver impregnation. On pretreating L-NAME, KA-induced neuronal degeneration decreased. COX-2 enzyme activities increased after KA injection in the dentate gyrus, CA 3, CA 1, amygdala and pyriform cortex, as determined by COX-2 staining. L-NAME pretreatment prior to KA-injection, caused COX-2 activities to increase compared with KA- injection only group by 1day and 2days survival time point. CONCLUSION: These results suggest that L-NAME has a neuroprotective effect on KA-induced neuronal damage, especially during the early stage of neurodegeneration.
Subject(s)
Animals , Rats , Amygdala , Brain , Dentate Gyrus , Hippocampus , Kainic Acid , Neurons , Neuroprotective Agents , NG-Nitroarginine Methyl Ester , Nitric Oxide Synthase , Prosencephalon , Prostaglandin-Endoperoxide Synthases , Seizures , SilverABSTRACT
Aim A UVA-induced apoptotic model of HaCaT cells was established to investigate the impact of UVA on c-jun/cyclooxygenase-2(COX-2)and explore related molecular mechanism of the polypeptide from Chlamys farreri(PCF)protecting HaCaT cells from UVA-induced apoptosis.Methods Cells were divided into five groups:control group,UVA model group,UVA+5.69 mmol?L-1 PCF group,UVA+2.84 mmol?L-1 PCF group,UVA+1.42 mmol?L-1 PCF group.Expression level of c-jun was assayed by Real-Time PCR and Western blot.RT-PCR and Western blot analysis were used to determine the mRNA and protein levels of COX-2.Using agarose gel electrophoresis,the effects of PCF and COX-2 inhibitor celecoxib on UVA-induced apoptosis were also investigated.Results PCF and celecoxib had inhibitory effect on 8 J?cm-2 UVA-induced apoptosis of HaCaT cells.COX-2 mRNA and protein levels increased after UVA radiation and the discrepancy was significant compared with control group(P
ABSTRACT
PURPOSE: Epidemiologic studies have indicated that the use of nonsteroidal anti-inflammatory drugs, which inhibit cyclooxygenase activity, reduce the risk of colorectal cancer. In addition, several studies have demonstrated the increased expression of cyclooxygenase-2 (COX-2) in human colorectal cancer tissues. However, the role of COX-2 in colorectal cancer has not been fully established. The aim of this study was to clarify the clinicopathologic significance of COX-2 expression in human colorectal cancer. METHODS: We performed immunohistochemical straining for COX-2 expression in 124 human colorectal cancer specimens. COX-2 expression was then compared with clinicopathologic factors and survival outcomes. RESULTS: COX-2 was expressed in the cytoplasm of the cancer cells. COX-2 expression was noted in 86.3% of the cancer patients and significantly correlated with the histologic type. The depth of invasion, tumor size, lymph node metastasis and stage were not correlated with COX-2 expression. Multivariate analysis for the factors associated with survival showed that serum CEA, size, depth and lymph node involvement correlated with survival, but COX-2 expression had no correlation. CONCLUSION: These data suggest that COX-2 expression in primary lesion of colorectal cancer may not be a useful marker for evaluating prognosis. However, further studies are necessary for identification of the roles in colorectal carcinogenesis.
Subject(s)
Humans , Carcinogenesis , Colorectal Neoplasms , Cyclooxygenase 2 , Cytoplasm , Epidemiologic Studies , Immunohistochemistry , Lymph Nodes , Multivariate Analysis , Neoplasm Metastasis , Prognosis , Prostaglandin-Endoperoxide SynthasesABSTRACT
Objective To assess the effect of atorvastatin on the Lipopolysaccharide (LPS)-induced cyclooxygenase-2 (COX-2) expression in cultured human pulmonary epithelial cells (A549). Methods A549 cells were incubated in the medium containing LPS and different concentrations of atorvastatin(0,10,15,20?M/ml, respectively) for 12h. Then the total cellular RNA and proteins from the cells treated with different experimental conditions were extracted for RT-PCR and western blot analysis,respectively. Results In cultured human pulmonary epithelial cells, atorvastatin reduced the expression of COX-2 mRNA and protein induced by LPS in a dose-dependent manner. Conclusion Atorvastatin may down-regulate LPS-induced COX-2 expression in cultured human pulmonary epithelial cells.