RESUMEN
The aim of this study was to evaluate whether the sub-chronic systemic ethanol exposure has direct effect on cavernosal smooth muscle contractions induced by KCl (depolarizing) and phenylephrine (α1-receptor agonist), and the possible involvement of RhoA/Rho-kinase pathway. Sub-chronic systemic ethanol was applied to mice with inhalation route for 14 days. The blood levels in ethanol-treated mice averaged 121.2 ± 9.1 mg/dl. KCl (80 mM) and phenylephrine (10 nM-100 µM) induced sustained contractions in corpus corporal strips from sham-treated mice. Sub-chronic ethanol treatment reduced the contractions to KCl. However, phenylephrine-induced contractions were not affected by ethanol treatment. Rho-kinase inhibitor fasudil (50 µM) and Y-27632 (50 µM) inhibited contractions to KCl and phenylephrine in sham-treated mice. Ethanol treatment increased the inhibitory effect of Rho-kinase inhibitors on contractions to phenylephrine. The relaxations induced by fasudil (100 µM) and Y-27632 (500 µM) did not change in ethanol treatment group. In ethanol-treated group, the expression of RhoA decreased compared to sham-treated group. Also, ROCK1 expression was reduced by ethanol but not statically significant to sham-treated group; however, the expression of ROCK2 increased in ethanol group. From these findings, it seems that phenylephrine and KCl-induced contractions depends on RhoA/Rho-kinase-mediated Ca(2+) sensitization. Also, these results suggest that the ethanol treatment decreased the expression of RhoA, and the inhibitory effect of ethanol on KCl-induced contractions may be due to, at least in part, the inhibition of a RhoA/Rho-kinase in mouse corpus cavernosum.
Asunto(s)
Etanol/farmacología , Músculo Liso/efectos de los fármacos , Pene/efectos de los fármacos , Proteínas de Unión al GTP rho/metabolismo , Animales , Etanol/sangre , Masculino , Ratones , Contracción Muscular/efectos de los fármacos , Músculo Liso/fisiología , Pene/metabolismo , Pene/fisiología , Fenilefrina/farmacología , Cloruro de Potasio/farmacología , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoARESUMEN
Calcium sensitization by the RhoA/Rho-kinase (ROCK) pathway contributes to the contraction in smooth muscle. Contractile stimuli can sensitize myosin to Ca(2+) by activating RhoA/Rho-kinase that inhibits myosin light chain phosphatase activity. The present study was aimed at investigating the possible involvement of RhoA/Rho-kinase pathway in contractile responses to agonist (phenylephrine) and depolarizing (KCl) of mouse lung parenchymal tissues. Also, we investigated the effect of ethanol on RhoA/Rho-kinase pathway. Phenylephrine (10(-8)-10(-4) M) and KCl (10-80 mM) induced sustained contractions in parenchymal strips. Ethanol significantly attenuated the contractions to phenylephrine and KCl. The Rho-kinase inhibitors fasudil (5×10(-5) M) and Y-27632 (5×10(-5) M) inhibited contractions to in both control and ethanol-treated parenchymal strips. In addition, the relaxations induced by fasudil (10(-4) M) and Y-27632 (5×10(-4) M) on parenchymal strips contracted by phenylephrine but not KCl was decreased in ethanol-treatment group. Also, RhoA, ROCK1 and ROCK2 expressions were detected in mouse lung parenchymal tissue. In ethanol-treated group, expression of RhoA and ROCK1 but not ROCK2 decreased compared to control. Furthermore, ethanol causes apoptotic changes in alveolar type I epithelial cells of parenchymal tissue. These results suggest that RhoA/Rho-kinase signaling pathway plays an important role in phenylephrine- and KCl-induced Ca(2)(+) sensitization in mouse lung parenchymal tissue. Also, ethanol may be decrease phenylephrine- and KCl-induced contraction due to lowering the RhoA/Rho-kinase-mediated Ca(2+)-sensitizing by inhibiting RhoA/Rho-kinase pathway in parenchymal tissue. These results may be lead to important insights into the mechanisms of lung diseases due to alcohol consumption.
Asunto(s)
Calcio/fisiología , Etanol/farmacología , Pulmón/efectos de los fármacos , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Amidas/farmacología , Animales , Pulmón/patología , Pulmón/fisiología , Pulmón/ultraestructura , Masculino , Ratones , Microscopía Electrónica , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Fenilefrina , Cloruro de Potasio , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Transducción de Señal/efectos de los fármacos , Quinasas Asociadas a rho/antagonistas & inhibidoresRESUMEN
BACKGROUND/AIM: In this study, the in vitro and in vivo effectiveness of caffeic acid (3,4-dihydroxycinnamic acid) phenethyl ester (CAPE) in combination with bortezomib, a proteasome inhibitor, was explored in multiple myeloma (MM) cells. MATERIALS AND METHODS: The cytotoxic effects of CAPE and bortezomib were determined by XTT cell proliferation assay. Apoptosis levels were analyzed with annexin V-fluorescein isothiocyanate, nuclear factor kappa beta (NF-κB) was analyzed with electrophoretic mobility-shift assay, and interleukin (IL)-6 levels were analyzed with enzyme-linked immunosorbent assay to evaluate CAPE's mechanism of action. To investigate the in vivo effectiveness of CAPE and bortezomib, an experimental plasmacytoma model was induced in BALB/c mice. RESULTS: Increasing concentrations of CAPE and bortezomib decreased the proliferation of ARH-77 cells in a dose-dependent manner. With doses of CAPE IC50, a significant increase in apoptosis and a significant decrease in IL-6 levels were detected. The NF-κB DNA- binding activity decreased compared to the basal ARH-77 level. The administration of CAPE alone or in combination with bortezomib increased the rate of survival compared to the control group. CONCLUSION: We think that our study, which is the first to demonstrate the in vitro and in vivo effectiveness of the.combined use of CAPE and bortezomib, will be a pioneer for future human applications of CAPE in MM.
Asunto(s)
Antineoplásicos/farmacología , Ácidos Borónicos/farmacología , Ácidos Cafeicos/farmacología , Supervivencia Celular/efectos de los fármacos , Mieloma Múltiple , Alcohol Feniletílico/análogos & derivados , Pirazinas/farmacología , Animales , Apoptosis/efectos de los fármacos , Bortezomib , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Interleucina-6/metabolismo , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Alcohol Feniletílico/farmacología , Análisis de SupervivenciaRESUMEN
Intestinal epithelial differentiation entails the formation of highly specialized cells with specific absorptive, secretory, digestive and immune functions. Cell-cell and cell-microenvironment interactions appear to be crucial in determining the outcome of the differentiation process. Using the Caco-2 cell line, which undergoes spontaneous re-differentiation when grown past confluency, we observed a loss of VCAM-1 (vascular cell adhesion molecule 1) mRNA expression, while ICAM-1 (intercellular cell adhesion molecule 1) mRNA expression was seen to increase over the course of differentiation. Protein kinase Cθ (PKCθ) acted downstream of protein kinase Cα (PKCα) to inactivate inhibitor of κB (IκB) and activate nuclear factor κB (NF-κB) in undifferentiated cells, and this pathway was inhibited in the differentiated cells. The increase in ICAM-1 mRNA expression in the differentiated cells was due to increased promoter recruitment of C/EBPß, which transcriptionally up-regulated ICAM-1 mRNA. However, protein expression of ICAM-1 was found to decrease over the course of differentiation due to degradation in the proteasome and lysosome. Immunohistochemistry using tumor samples from colon cancer patients indicated that non-transformed matched normal cells (well-differentiatied) showed no ICAM-1 expression, but the poorly differentiated tumor cells showed higher expression. Functionally, a decrease in adhesion to human umbilical vein endothelial cells was observed in the differentiated Caco-2 cells. Thus, regulation of ICAM-1 and VCAM-1, although both NF-κB target genes, appears to be different over the course of epithelial differentiation in Caco-2 cells.
Asunto(s)
Diferenciación Celular/fisiología , Regulación de la Expresión Génica/fisiología , Molécula 1 de Adhesión Intercelular/biosíntesis , Molécula 1 de Adhesión Celular Vascular/biosíntesis , Células CACO-2 , Diferenciación Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Humanos , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , ARN Mensajero/metabolismoRESUMEN
Cellular differentiation in the gut is vital in maintaining the cellular and functional specialization of the epithelial layer. MicroRNAs (miRNAs) have recently emerged as one of the key players in orchestrating the differentiation process in the gut. Using the spontaneously differentiating Caco-2 cell line, we observed an increased expression of miR-146a but not miR-146b in the course of differentiation. Bioinformatic analyses revealed that the membrane type matrix metalloprotease 16 (MMP16, MT3-MMP) was a predicted target of miR-146a and a decrease in the mRNA and protein expression of MMP16 was observed in the course of differentiation. Transfection of a luciferase reporter vector containing the 3'UTR of MMP16 showed decreased luciferase activity due to miR-146a expression. With forced expression of miR-146a in undifferentiated Caco-2 cells, a decrease in the mRNA and protein levels of MMP16 and a lower gelatinase activity in a gelatin zymogram were observed. Additionally, forced expression of miR-146a in HT-29 colon cancer cells also resulted in decreased expression of MMP16, along with a decrease in the invasion through Matrigel. Taken together, we have shown here that MMP16 is regulated by miR-146a in spontaneously differentiated Caco-2 cells. As MMP16 activates the zymogen of MMP2, which is known to degrade extracellular matrix proteins, the regulation of MMP16 by miR-146a may account, at least in part, for lower motility of well-differentiated cells.