RESUMO
OBJECTIVE: To study the effect of pioglitazone, a synthetic peroxisome proliferator-activated receptor γ (PPARγ) agonist, on the RANKL-mediated osteoclastogenesis of osteoclast precursor cells, and to explore the function and mechanism of PPARγ in the osteoclast differentiation. METHODS: Pioglitazone treatment of RAW264.7 murine macrophages were compared with those of simply cultured control and RANKL-mediated control. Accordingly, the RANKL-mediated cells were cultured with 30 ng/ml RANKL, then induced into significant multinuclear osteoclast formation. And pioglitazone treated cells were exposed to 10 µmol/L pioglitazone during the process of osteoclast differentiation under RANKL. The number of mature osteoclasts was calculated and the mRNA levels of RANK analyzed by real-time quantitative PCR. RESULTS: Pioglitazone significantly inhibited osteoclastogenesis of osteoclast precursor cells, the number of mature osteoclasts of pioglitazone treated group was (176 ± 58)/cm(2) and significantly less than the mature cells of RANKL induced group which number was (322 ± 74)/cm(2) (P < 0.01); and pioglitazone also significantly inhibited the mRNA expression of RANK, a typical differentiated factor of osteoclast, the number of the mRNA expression of RANK of pioglitazone treated group was 2.16 ± 0.74 and significantly less than the number of RANKL induced group (4.94 ± 0.39, P < 0.01). CONCLUSION: PPARγ agonist inhibited the differentiation of RAW264.7 towards osteoclast. It might be due to the suppression of RANK gene expression in the process of osteoclast differentiation.
Assuntos
Osteoclastos/citologia , PPAR gama/agonistas , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Tiazolidinedionas/farmacologia , Animais , Diferenciação Celular , Linhagem Celular , Camundongos , Osteoclastos/metabolismo , Pioglitazona , Ligante RANK/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Gastrin and cyclooxygenase-2 (COX-2) play important roles in the carcinogenesis and progression of gastric cancer. However, it remains unknown whether the combination of cholecystokinin-2 (CCK-2) receptor antagonist plus COX-2 inhibitor exerts synergistic anti-tumor effects on human gastric cancer. Here, we demonstrated that the combination of AG-041R (a CCK-2 receptor antagonist) plus NS-398 (a selective COX-2 inhibitor) treatment had synergistic effects on proliferation inhibition, apoptosis induction, down-regulation of Bcl-2 and up-regulation of Bax expression in MKN-45 cells. These results indicate that simultaneous targeting of CCK-2 receptor and COX-2 may inhibit gastric cancer development more effectively than targeting either molecule alone.
Assuntos
Inibidores de Ciclo-Oxigenase 2/farmacologia , Receptor de Colecistocinina B/antagonistas & inibidores , Neoplasias Gástricas/patologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Gastrinas/análise , HumanosRESUMO
OBJECTIVE: To investigate the mechanism of BVT.2733 on insulin resistance, by using diet-induced obese (DIO) mice model. METHODS: After having been balanced for 3 days, the C57BL/6J mice were randomly divided into a normal diet group and a high-fat diet (HFD) group. After 20 weeks, the obese mice were further randomly divided into an obese control group, a BVT.2733 group and a pioglitazone (PGZ) group and they were orally administered with placebo, BVT.2733 and PGZ separately for two weeks. Adiponectin and leptin mRNA expression levels from adipose tissue were analyzed with real-time quantitative PCR. The levels of plasma glucose, serum insulin and adiponectin were measured with biochemical technology, radioimmunoassay and ELISA. Adipocyte sizes were observed with immunohistochemistry. RESULTS: The body weight, plasma glucose and serum insulin levels raised (P < 0.05) in the HFD group and the adipocyte sizes were bigger. Serum insulin levels significantly reduced (P < 0.05) and adipocyte sizes reduced, while plasma adiponectin level raised (P < 0.01) in the two treatment groups as compared with those in obese controls. Both the mRNA expressions of adiponectin and leptin upregulated (P < 0.05) in the PGZ group, but their expressions in the BVT.2733 group did not alter significantly. The body weight of the mice reduced significantly in the BVT.2733 group. CONCLUSION: BVT.2733 can reduce body weight significantly and improve insulin resistance, but cannot influence the expression of adipocytokines.
Assuntos
Hipoglicemiantes/farmacologia , Resistência à Insulina , Piperazinas/farmacologia , Sulfonamidas/farmacologia , Tiazóis/farmacologia , Tiazolidinedionas/farmacologia , Tecido Adiposo/metabolismo , Animais , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , PioglitazonaRESUMO
OBJECTIVE: To evaluate the efficacy and safety of nateglinide, a new antidiabetic agent, in the treatment of type 2 diabetes. METHODS: A total of 219 treatment-naïve patients with type 2 diabetes from 6 centers were enrolled in this study and blindly divided into nateglinide group (n = 105) and repaglinide group (n = 114). In all patients, the disease was confirmed for at least three months. The whole observation lasted for 12 weeks. The efficacy indicators measured include glycohemoglobin A1c (HbA1c), fasting blood glucose, and 2 hours postprandial blood glucose, and the safety parameters measured included renal and hepatic function, serum lipids, and blood and urea profiles. RESULTS: Similar decreases in fasting blood glucose, 2 hours postprandial blood glucose, and HbA1 c were found in both nateglinide group and repaglinide group without significant differences. No severe adverse events were noted. The hypoglycemia event reports were not significantly different between these two groups. CONCLUSION: Nateglinide is an effective and safe drug in treating type 2 diabetes.
Assuntos
Cicloexanos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Fenilalanina/análogos & derivados , Glicemia/efeitos dos fármacos , Cicloexanos/administração & dosagem , Cicloexanos/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Nateglinida , Fenilalanina/administração & dosagem , Fenilalanina/efeitos adversos , Fenilalanina/uso terapêutico , Resultado do TratamentoRESUMO
BACKGROUND: We previously demonstrated that maternal exposure to di-n-butyl phthalate (DBP) induces dysplasia of the kidney in newborn male offspring and renal fibrosis in adults. But the underlying mechanisms remain elusive. Fgf10/Fgfr2 and androgen receptor (AR) are known to be important for renal development. We therefore investigated whether these genes are involved in DBP-induced renal fibrosis. MATERIALS AND METHODS: Using Sprague-Dawley rats and rat renal proximal tubular cells (NRK52E), we determined the potential involvement of Fgf10, Fgfr2 and AR in DBP-induced renal fibrosis. RESULTS: We found that maternal exposure to DBP induces renal fibrosis in adult male offspring. A lower serum testosterone concentration and reduced expression of Fgf10, Fgfr2 and AR were detected in these animals. These was a trend toward lower expression of Fgf10, Fgfr2 and AR in NRK52E cells subjected to DBP exposure. Furthermore, higher expression levels of TGF-ß and α-SMA were observed in abnormal renal tissue and DBP-treated NRK52E cells. CONCLUSION: Our findings suggest the potential involvement of Fgf10/Fgfr2 and AR in renal fibrosis of adult male rat offspring induced by prenatal exposure to DBP. The anti-androgenic effects of DBP might play an important role in this pathological process.
Assuntos
Dibutilftalato/toxicidade , Poluentes Ambientais/toxicidade , Fator 10 de Crescimento de Fibroblastos/metabolismo , Rim/patologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Receptores Androgênicos/metabolismo , Animais , Feminino , Fibrose , Rim/embriologia , Rim/metabolismo , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos Sprague-DawleyRESUMO
Physiological levels of glucocorticoids (GCs) are required for proper metabolic control, and excessive GC action has been linked to a variety of pandemic metabolic diseases. MicroRNA (miRNA)-19b plays a critical role in the pathogenesis of GC-induced metabolic diseases. This study explored the potential of miRNA-based therapeutics targeting adipose tissue. Our results showed that overexpressed miR-19b in stromal vascular fraction (SVF) cells derived from subcutaneous adipose tissue had the same effects as dexamethasone (DEX) treatment on the inhibition of adipose browning and oxygen consumption rate. The inhibition of miR-19b blocked DEX-mediated suppression of the expression of browning marker genes as well as the oxygen consumption rate in differentiated SVF cells derived from subcutaneous and brown adipose tissue. Overexpressed miR-19b in SVF cells derived from brown adipose tissue had the same effects as DEX treatment on the inhibition of brown adipose differentiation and energy expenditure. Glucocorticoids transcriptionally regulate the expression of miR-19b via a GC receptor-mediated direct DNA binding mechanism. This study confirmed that miR-19b is an essential target for GC-mediated control of adipose tissue browning. It is hoped that the plasticity of the adipose organ can be exploited in the next generation of therapeutic strategies to combat the increasing incidence of metabolic diseases, including obesity and diabetes.
Assuntos
Adipogenia , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Metabolismo Energético , Glucocorticoides/metabolismo , MicroRNAs/metabolismo , Receptores de Glucocorticoides/agonistas , Células 3T3-L1 , Adipogenia/efeitos dos fármacos , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/citologia , Tecido Adiposo Branco/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Células Cultivadas , Dexametasona/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Metabolismo Energético/efeitos dos fármacos , Glucocorticoides/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/antagonistas & inibidores , Mutação , Consumo de Oxigênio/efeitos dos fármacos , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA/antagonistas & inibidores , RNA/metabolismo , Receptores de Glucocorticoides/metabolismo , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Gordura Subcutânea/citologia , Gordura Subcutânea/efeitos dos fármacos , Gordura Subcutânea/metabolismoRESUMO
BACKGROUND: Increased reactive oxygen species (ROS) formation, which in turn promotes cardiomyocytes apoptosis, is associated with the pathogenesis and progression of various cardiac diseases such as ischemia and heart failure. Recent studies have shown that over expression of heat shock protein 27 (Hsp27) confers resistance to cardiac ischemia/reperfusion injury. However, not much is known about the regulation of myocyte survival by Hsp27. METHODS: The rat cardiac cell line H9c2, with a stable overexpression of Hsp27, was established, with empty vector transfected H9c2 cells as controls. Following the cells challenged by Hydrogen Peroxide (H2O2), lactate dehydrogenase (LDH) release, apoptosis, intracellular ROS, cell morphology, mitochondrial transmembrane potential and the activation of serine/threonine kinase Akt were determined. RESULTS: Along with marked suppression of H2O2-induced injury by Hsp27 overexpression in H9c2 cells, ROS generation and the loss of mitochondrial membrane potential were also significantly depressed. Furthermore, augmented Akt activation was observed in Hsp27 overexpressed H9c2 cells following H2O2 exposure. CONCLUSIONS: Hsp27 inhibits oxidative stress-induced H9c2 damage and inhibition of ROS generation and the augmentation of Akt activation may be involved in the protective signaling.
Assuntos
Apoptose , Proteínas de Choque Térmico/fisiologia , Miócitos Cardíacos/patologia , Proteínas de Neoplasias/fisiologia , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular , Proteínas de Choque Térmico HSP27 , Humanos , Peróxido de Hidrogênio/toxicidade , Chaperonas Moleculares , RatosRESUMO
OBJECTIVE: To investigate the regulative roles of the gastrin receptor antagonist proglumide and the specific cyclooxygenase (COX)-2 inhibitor NS-398 on the proliferation and apoptosis of gastric cancer cells. METHODS: Human gastric cancer cells of the line MKN-45 were routinely cultured in RPMI-1640 medium supplemented with 10% heat-inactivated fetal calf serum. Subconfluent cell cultures were treated with proglumide at a final concentration of 5 mmol/L, NS-398 at a final concentration of 10.0 micromol/L, or proglumide in combination with NS-398 for 48 h. The growth and proliferation of MKN-45 cells were analyzed with MTT assay. Flow cytometric analysis was used to detect the apoptosis of the gastric cancer cells. RT-PCR and Western blotting were used to detect the expression of apoptosis-inhibited gene bcl-2 mRNA and protein. RESULTS: The apoptosis rates of the cells treated by proglumide, NS-398, and combination of two agents were 24.7% +/- 3.2%, 26.7% +/- 3.4%, and 36.1% +/- 4.6% respectively, all significantly higher than that in the control group (1.6% +/- 0.6%, all P < 0.01). The apoptosis rates of the MKN-45 cells treated with proglumide combined with NS-398 was significantly greater than those of the cells treated by the two agents alone (both P < 0.05). Treatment with proglumide and NS-398 significantly reduced the bcl-2 mRNA and protein expression in the MKN-45 cells (P < 0.05). CONCLUSION: Both proglumide and NS-398 inhibit the proliferation and induce the apoptosis of human gastric cells. This apoptosis may be mediated by down-regulation of the expression of apoptosis-inhibited gene bcl-2. Co-treatment with proglumide and NS-398 have synergistic anticancer role.
Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Proglumida/farmacologia , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Nitrobenzenos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Sulfonamidas/farmacologiaRESUMO
OBJECTIVE: To investigate the sleep status of college and high schools students. METHODS: Pittsburgh sleep quality index (PSQI) and self-manufactured questionnaires about siesta habits were used as tools. Three groups of students from medical college (MC), senior high school (SS) and junior high school (JS) were surveyed. RESULTS: In the group MC, SS and JS, the occurrence rates of sleep disorders were 27%, 62% and 54%, respectively, and in which the appearance rates of insomnia were 17%, 19% and 19%, longing for sleep were 10%, 43% and 35% respectively. And there were no significant difference between schoolboy and schoolgirl. The occurrence rates of slack breathing were different (5/155, 1/154) significantly between group SS and JS. The distinct differences also were found in group JS and MC, in which students felt hot (10/155, 1/122) and in all the three groups, in which students felt sleepy (55/155, 62/154, 13/122) whereas the difference of sleepy between group SS and JS was comparatively distinct (55/155, 62/154). Significant differences were also found between group JS and SS, MC in average sleep time of (7.65 +/- 0.87) hours, (7.16 +/- 0.83) hours, and (7.10 +/- 0.57) hours. The time of falling asleep (median 15 min, 10 min, 20 min) and siesta habit (8/155, 19/154, 75/122) among group MC and SS, JS were different respectively and markedly, whereas siesta habit differences between group SS and JS were comparatively distinct (8/155, 19/154). CONCLUSION: Students in high school showed higher rate of longing for sleep, and this implicated they fall short of sleep time greatly and siesta could improve their sleepy signs.
Assuntos
Distúrbios do Início e da Manutenção do Sono/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Adolescente , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Prevalência , Sono/fisiologia , Estudantes , Inquéritos e QuestionáriosRESUMO
Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that can severely disrupt the synthesis and secretion of endocrine hormones. To investigate the effects of 2,3',4,4',5-pentachlorobiphenyl (PCB118) on thyroid structure and function, 40 male Wistar rats were divided into 4 equal treatment groups and administered vehicle or one of three doses of PCB118. The experimental groups received intraperitoneal (i.p.) injection of 10, 100, or 1000µg/kg/day PCB118, 5 days per week for 13 weeks, whereas the control group was injected with corn oil (vehicle). Serum concentrations of free thyroxine (FT4), free triiodothyronine (FT3) and thyroid stimulating hormone (TSH) were measured by radioimmunoassays. Histopathological and ultrastructural changes in the thyroid were observed under light microscopy and transmission electron microscopy (TEM). The mRNA expression levels of the sodium-iodide symporter (NIS) and thyroglobulin (TG) were quantified by real-time PCR. Increasing doses of PCB118 resulted in progressively lower FT3, FT4 and TSH concentrations in serum. Injection of PCB118 at all doses led to histopathological deterioration of the thyroid characterized by follicular hyperplasia and expansion, shedding of epithelial cells and fibrinoid necrosis. Follicle cells exhibited swollen or vacuolated endoplasmic reticula, as revealed by TEM. Exposure to PCB118 also caused significant decreases in NIS and TG mRNA expression levels. Chronic exposure to low-dose PCB118 and other PCB congeners may be a significant risk factor for thyroid diseases.
Assuntos
Poluentes Ambientais/toxicidade , Bifenilos Policlorados/toxicidade , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/patologia , Animais , Relação Dose-Resposta a Droga , Poluentes Ambientais/administração & dosagem , Masculino , Microscopia Eletrônica de Transmissão , Bifenilos Policlorados/administração & dosagem , RNA Mensageiro/análise , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Simportadores/biossíntese , Tireoglobulina/biossíntese , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangueRESUMO
Although inhibition of cyclooxygenase-2 (COX-2) or activation of peroxisome proliferators-activated receptor gamma (PPAR-gamma) leads to growth inhibition in malignancies, the synergistic anti-tumor effects of combination of COX-2 inhibitor (NS-398) and PPAR-gamma agonist (rosiglitazone) on the human pancreatic cancer cells remains unknown. Here, we evaluated the effects of NS-398 and/or rosiglitazone on the cell proliferation and apoptosis in a pancreatic cancer cell line, SW1990. NS-398 and rosiglitazone decreased cell proliferation in a dose- and time-dependent manner. Proliferating cell nuclear antigen (PCNA) labeling index significantly decreased in the cells treated with either NS-398 or rosiglitazone. Both NS-398 and rosiglitazone alone induced apoptotic cell death of SW1990. The combination of NS-398 and rosiglitazone exerted synergistic effects on proliferation inhibition, and apoptosis induction in SW1990 cells, with down-regulation of Bcl-2 and up-regulation of Bax expression. Our results indicate that simultaneous targeting of COX-2 and PPAR-gamma inhibits pancreatic cancer development more effectively than targeting each molecule alone.
Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , PPAR gama/agonistas , Neoplasias Pancreáticas/patologia , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Humanos , Imuno-Histoquímica , Nitrobenzenos/farmacologia , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Rosiglitazona , Sulfonamidas/farmacologia , Tiazolidinedionas/farmacologiaRESUMO
AIM: To investigate the relationship between 11 beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), a potential link between obesity and type 2 diabetes, and preadipocyte differentiation. METHODS: Mouse 11beta-HSD1 siRNA plasmids were transfected into 3T3-L1 preadipocytes (a cell line derived from mouse Swiss3T3 cells that were isolated from mouse embryo), for examination of the effect of targeted 11beta-HSD1 inhibition on differentiation of 3T3-L1 cells. Differentiation was stimulated with 3-isobutyl-1-methyxanthine, insulin, and dexamethasone. The transcription level of the genes was detected by real-time PCR. RESULTS: Lipid accumulation was significantly inhibited in cells transfected with mouse 11beta-HSD1 siRNA compared with non-transfected 3T3-L1 cells. Fewer lipid droplets were detected in the transfected cells both prior to stimulation and after stimulation with differentiation-inducing reagents. The expression of adipocyte differentiation-associated markers such as lipoprotein lipase and fatty acid synthetase were downregulated in the transfected cells. Similarly, the expression of preadipocyte factor-1, an inhibitor of adipocyte differentiation, was downregulated upon stimulation of differentiation and had no changes in the transfected cells. CONCLUSION: 11 beta-HSD1 can promote preadipocyte differentiation. Based on this, we propose that 11 beta-HSD1 may be an important candidate mediator of obesity and obesity-induced insulin resistance.
Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/fisiologia , Adipócitos/citologia , Diferenciação Celular , Células 3T3-L1 , Animais , Camundongos , RNA Mensageiro/análise , Receptores de Glucocorticoides/genética , TransfecçãoRESUMO
AIM: To observe the roles of 11-beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) in in vitro preadipocyte differentiation and in rats with diet-induced obesity (DIO). METHODS: Protein expression of 11beta-HSD1 in the process of 3T3-L1 cell differentiation and in various tissues of the rats were detected by Western blot analysis; expression of 11beta-HSD1 mRNA and glucocorticoid receptor (GR) and other marker genes of preadipocyte differentiation were detected by using real-time PCR. RESULTS: Lipid droplets in 3T3-L1 cells accumulated and increased after stimulation. A dramatically elevated protein level of 11beta-HSD1, especially in the late stages of 3T3-L1 cell differentiation, was detected. The relative mRNA levels of 11beta-HSD1, GR and cell differentiation markers LPL, aP2, and FAS were upregulated, and Pref-1 was downregulated during the differentiation. In DIO rats, bodyweight, visceral adipose mass index and the protein expression of 11beta-HSD1 increased, especially in adipose tissue, brain and muscles. Serum insulin, triglyceride, total cholesterol and low-density lipoprotein cholesterol were found to be increased in DIO rats, but without any obvious changes in blood glucose or tumor necrosis factor-alpha levels. CONCLUSION: 11beta-HSD1 may promote preadipocyte differentiation, and may be involved in the development of obesity.
Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/biossíntese , Adipócitos/enzimologia , Obesidade/enzimologia , Receptores de Glucocorticoides/biossíntese , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Diferenciação Celular , Colesterol/sangue , Ácido Graxo Sintases/metabolismo , Insulina/sangue , Lipase Lipoproteica/metabolismo , Masculino , Camundongos , Obesidade/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/genética , Triglicerídeos/sangueRESUMO
BACKGROUND AND AIM: It is known that cyclooxygenase (COX)-2 is over expressed in gastrointestinal neoplasia and Helicobacter pylori (H. pylori) infection is causally linked to gastric cancer. The present study aimed to elucidate the effects of H. pylori on COX-2 expression and prostaglandinE(2) (PGE(2)) production in a gastric epithelial cell line derived from normal rat gastric mucosa (RGM1). METHOD: H. pylori water extracts were prepared from a supernatant of the H. pylori suspension in distilled water. RGM1 cells were cultured with H. pylori water extracts at the final concentration of 2.5, 5, 10 microg/mL for 24 h. For the time sequence study, RGM1 cells were cultured with 10 microg/mL H. pylori water extracts for 0, 6, 12, 24 and 48 h. COX-1 and COX-2 expression in the RGM1 cells was analyzed by western blotting. The levels of PGE(2) in the cultured media were measured by enzyme immunoassay. RESULTS: H. pylori did not affect COX-1 expression; whereas COX-2 expression increased by six-fold at 24 h after incubation of RGM1 cells with 10 microg/mL H. pylori water extracts. The increase in COX-2 expression was evident after 12 h of incubation; reached a peak at 24 h and declined at 48 h. H. pylori dose dependently increased COX-2 expression and PGE(2) synthesis in RGM1 cells. CONCLUSION: H. pylori induces COX-2 expression and increases PGE(2) synthesis in RGM1 cells in vitro. These results indicate that H. pylori-associated gastric carcinogenesis may depend on COX-2 expression.
Assuntos
Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Helicobacter pylori/fisiologia , Animais , Células Cultivadas , Expressão Gênica/fisiologia , Ratos , Ratos WistarRESUMO
OBJECTIVE: To investigate the expression of cyclooxygenase (COX)-2 and matrix metalloproteinase (MMP)-9 in gastric carcinomas, and to correlate this expression with clinicopathological parameters and angiogenesis. METHODS: Ninety-six resected tumor specimens from patients with gastric carcinoma were obtained, and 30 corresponding paracancerous normal tissues were randomly selected as a control. Immunohistochemical staining was used for detecting the expression of COX-2 and MMP-9. Monoclonal antibody against CD34 was used for displaying vascular endothelial cells, and microvascular density (MVD) was calculated by counting of CD34-positive vascular endothelial cells. RESULTS: The positive expression rates of COX-2, MMP-9 and MVD in the cancerous tissue were 80.2%, 74.0%, and 32.5 +/- 8.3, respectively, which were significantly higher than those in the normal tissue (P < 0.01). COX-2, MMP-9 expression rates and MVD in the patients with stages III and IV were 91.4%, 84.5% and 34.9 +/- 8.7, respectively, which were significantly higher than those in the patients with stages I and II (P < 0.01). In addition, the Spearman rank correlation test showed that tumor MVD was closely associated with COX-2 (r = 0.311, P < 0.01) and MMP-9 (r = 0.349, P < 0.01) expressions. CONCLUSIONS: Overexpression of COX-2 and MMP-9 is related to tumor invasion and lymph node metastasis in the gastric carcinoma. These results provide evidence that COX-2 contribute to gastric cancer development by promoting MMP-9 expression and angiogenesis.
Assuntos
Adenocarcinoma/irrigação sanguínea , Ciclo-Oxigenase 2/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Neovascularização Patológica/patologia , Neoplasias Gástricas/irrigação sanguínea , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Antígenos CD34/análise , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Microcirculação/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologiaRESUMO
AIM: Try to clarify the effects of HSF1 gene on the constitutively expressed alphaBC. METHODS: To investigate the levels of constitutively expressed alphaB-Crystallin (alphaBC) in hsf1 knockout (hsf1 -/-) and hsf1 wild type (hsf1 +/+) mice myocardium by Western blot and immunohistochemistry. RESULTS: The alphaBC levels in hsf1 -/- and hsf1 +/+ were 68.42% +/- 4.16%, 100% +/- 7.58%, respectively (P < 0.05, cytosolic fraction), and 20.53% +/- 1.01%, 37.55% +/- 1.91%, respectively (P < 0.05, pellet fraction). The alphaBC signals decreased significantly in hsf1 -/- myocardium compared with hsf1 +/+ myocardium stained with fluorescence immunohistochemistry. CONCLUSION: hsf1 is the important, but not the only factor, which mediates the constitutively expressed alphaBC.