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1.
PLoS One ; 16(4): e0251012, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914833

RESUMO

Asthma is a well-known bronchial disease that causes bronchial inflammation, narrowing of the bronchial tubes, and bronchial mucus secretion, leading to bronchial blockade. In this study, we investigated the association between phosphodiesterase (PDE), specifically PDE1, and asthma using 3-isobutyl-1-methylxanthine (IBMX; a non-specific PDE inhibitor) and vinpocetine (Vinp; a PDE1 inhibitor). Balb/c mice were randomized to five treatment groups: control, ovalbumin (OVA), OVA + IBMX, OVA + Vinp, and OVA + dexamethasone (Dex). All mice were sensitized and challenged with OVA, except for the control group. IBMX, Vinp, or Dex was intraperitoneally administered 1 h before the challenge. Vinp treatment significantly inhibited the increase in airway hyper-responsiveness (P<0.001) and reduced the number of inflammatory cells, particularly eosinophils, in the lungs (P<0.01). It also ameliorated the damage to the bronchi and alveoli and decreased the OVA-specific IgE levels in serum, an indicator of allergic inflammation increased by OVA (P<0.05). Furthermore, the increase in interleukin-13, a known Th2 cytokine, was significantly decreased by Vinp (P<0.05), and Vinp regulated the release and mRNA expression of macrophage inflammatory protein-1ß (MIP-1ß) increased by OVA (P<0.05). Taken together, these results suggest that PDE1 is associated with allergic lung inflammation induced by OVA. Thus, PDE1 inhibitors can be a promising therapeutic target for the treatment of asthma.


Assuntos
Anti-Inflamatórios/administração & dosagem , Asma/tratamento farmacológico , Quimiocina CCL4/genética , Regulação para Baixo , Ovalbumina/efeitos adversos , Alcaloides de Vinca/administração & dosagem , 1-Metil-3-Isobutilxantina/administração & dosagem , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Asma/induzido quimicamente , Asma/genética , Dexametasona/administração & dosagem , Dexametasona/farmacologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Alcaloides de Vinca/farmacologia
2.
J Assist Reprod Genet ; 36(3): 413-424, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30443692

RESUMO

PURPOSE: Oocyte maturation is a complex process involving nuclear and cytoplasmic modulations, during which oocytes acquire their ability to become fertilized and support embryonic development. The oocyte is apparently "primed" for maturation during its development in the dominant follicle. As bovine oocytes immediately resume meiosis when cultured, it was hypothesized that delaying resumption of meiosis with cyclic nucleotide modulators before in vitro maturation (IVM) would allow the oocytes to acquire improved developmental competence. METHODS: We tested the Simulated Physiological Oocyte Maturation (SPOM) system that uses forskolin and 3-isobutyl-1-methylxanthine for 2 h prior to IVM against two different systems of conventional IVM (Con-IVM). We evaluated the ultrastructure of matured oocytes and blastocysts and also assessed the expression of 96 genes related to embryo quality in the blastocysts. RESULTS: In summary, the SPOM system resulted in lower blastocyst rates than both Con-IVM systems (30 ± 9.1 vs. 35 ± 8.7; 29 ± 2.6 vs. 38 ± 2.8). Mature SPOM oocytes had significantly increased volume and number of vesicles, reduced volume and surface density of large smooth endoplasmic reticulum clusters, and lower number of mitochondria than Con-IVM oocytes. SPOM blastocysts showed only subtle differences with parallel undulations of adjacent trophectoderm plasma membranes and peripherally localized ribosomes in cells of the inner cell mass compared with Con-IVM blastocysts. SPOM blastocysts, however, displayed significant downregulation of genes related to embryonic developmental potential when compared to Con-IVM blastocysts. CONCLUSIONS: Our results show that the use of the current version of the SPOM system may have adverse effects on oocytes and blastocysts calling for optimized protocols for improving oocyte competence.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Fertilização in vitro/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos , Oócitos/efeitos dos fármacos , 1-Metil-3-Isobutilxantina/administração & dosagem , Animais , Blastocisto/efeitos dos fármacos , Blastocisto/patologia , Bovinos , Colforsina/administração & dosagem , Células do Cúmulo/efeitos dos fármacos , Feminino , Meiose/genética , Oócitos/crescimento & desenvolvimento , Oócitos/patologia , Oogênese/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Gravidez , Ribossomos/efeitos dos fármacos
3.
J Mol Cell Cardiol ; 121: 51-59, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29885334

RESUMO

In cardiac myocytes activation of an exchange factor activated by cAMP (Epac) leads to activation of phospholipase Cε (PLCε)-dependent hydrolysis of phosphatidylinositol 4-phosphate (PI4P) in the Golgi apparatus a process critical for development of cardiac hypertrophy. Here we show that ß-adrenergic receptor (ßAR) stimulation does not stimulate this pathway in the presence of the broad spectrum phosphodiesterase (PDE) inhibitor IBMX, but selective PDE3 inhibition revealed ßAR-dependent PI4P depletion. On the other hand, selective inhibition of PDE2 or PDE9A blocked endothelin-1 (ET-1) and cAMP-dependent PI4P hydrolysis by PLCε. Direct activation of protein kinase A (PKA), protein kinase G (PKG), or the atrial natriuretic factor (ANF) receptor abolished PI4P hydrolysis in response to multiple upstream stimuli. These results reveal distinct pools of cyclic nucleotides that either inhibit PLCε at the Golgi through PKA/PKG, or activate PLCε at the Golgi through Epac. These data together reveal a new mechanism by which ANF and selective PDE inhibitors can protect against cardiac hypertrophy.


Assuntos
Cardiomegalia/genética , Compartimento Celular/genética , Complexo de Golgi/genética , Nucleotídeos/genética , Fosfoinositídeo Fosfolipase C/genética , 1-Metil-3-Isobutilxantina/administração & dosagem , Proteínas de Ancoragem à Quinase A/genética , Proteínas de Ancoragem à Quinase A/metabolismo , Animais , Fator Natriurético Atrial/genética , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/patologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Complexo de Golgi/efeitos dos fármacos , Humanos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Nucleotídeos/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Fosfoinositídeo Fosfolipase C/metabolismo , Diester Fosfórico Hidrolases/genética , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta/genética , Transdução de Sinais/genética
4.
Artigo em Inglês | MEDLINE | ID: mdl-28799255

RESUMO

BACKGROUND: Gastroprokinetic properties of 5-HT4 receptor agonists, such as prucalopride, are attributed to activation of 5-HT4 receptors on cholinergic nerves innervating smooth muscle in the gastrointestinal smooth muscle layer, increasing acetylcholine release and muscle contraction. In porcine stomach and colon, phosphodiesterase (PDE) 4 has been shown to control the signaling pathway of these 5-HT4 receptors. The aim of this study was to investigate the PDE-mediated control of these 5-HT4 receptors in human large intestine. METHODS: Circular smooth muscle strips were prepared from human large intestine; after incubation with [³H]-choline, electrically induced tritium outflow was determined as a measure for acetylcholine release. The influence of PDE inhibition on the facilitating effect of prucalopride on electrically induced acetylcholine release was studied. KEY RESULTS: The non-selective PDE inhibitor IBMX enhanced the facilitating effect of prucalopride on electrically induced acetylcholine release. The selective inhibitors vinpocetine (PDE1), EHNA (PDE2) and cilostamide (PDE3) did not influence, while rolipram and roflumilast (PDE4) enhanced the prucalopride-induced facilitation to the same extent as IBMX. CONCLUSIONS & INFERENCES: In human large intestinal circular muscle, the intracellular pathway of 5-HT4 receptors facilitating cholinergic neurotransmission to large intestinal circular smooth muscle is controlled by PDE4. If the synergy between 5-HT4 receptor agonism and PDE4 inhibition is confirmed in a functional assay with electrically induced cholinergic contractions of human large intestinal circular smooth muscle strips, combination of a selective 5-HT4 receptor agonist with a selective PDE4 inhibitor might enhance the in vivo prokinetic effect of the 5-HT4 receptor agonist in the large intestine.


Assuntos
Acetilcolina/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Intestino Grosso/metabolismo , Receptores 5-HT4 de Serotonina/metabolismo , 1-Metil-3-Isobutilxantina/administração & dosagem , Idoso , Benzofuranos/administração & dosagem , Feminino , Humanos , Intestino Grosso/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Inibidores de Fosfodiesterase/administração & dosagem , Agonistas do Receptor 5-HT4 de Serotonina/administração & dosagem
5.
Physiol Rep ; 5(2)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28108651

RESUMO

Roflumilast is a cyclic nucleotide phosphodiesterase inhibitor that is FDA-approved for treatment of chronic obstructive pulmonary disease. With a view toward possible use for treatment of patients with X-linked nephrogenic diabetes insipidus (NDI) due to hemizygous mutations in the V2 vasopressin receptor, this study sought to determine the effect of roflumilast on aquaporin-2 (AQP2) phosphorylation, AQP2 trafficking, and water permeability in the rat inner medullary collecting duct (IMCD). In the presence of the vasopressin analog dDAVP (0.1 nmol/L), both roflumilast and its active metabolite roflumilast N-oxide (RNO) significantly increased phosphorylation at S256, S264, and S269, and decreased phosphorylation at S261 (immunoblotting) in IMCD suspensions in a dose-dependent manner (3-3000 nmol/L). Another commonly used phosphodiesterase inhibitor, IBMX, affected phosphorylation only at the highest concentration in this range. However, neither roflumilast nor RNO had an effect on AQP2 phosphorylation in the absence of vasopressin. Furthermore, roflumilast alone did not increase AQP2 trafficking to the plasma membrane (immunofluorescence) or increase water permeability in freshly microdissected perfused IMCD segments. We conclude that roflumilast can be used to enhance vasopressin's action on AQP2 activity in the renal collecting duct, but has no detectable effect in the absence of vasopressin. These findings suggest that roflumilast may not have a beneficial effect in X-linked NDI, but could find useful application in acquired NDI.


Assuntos
Aminopiridinas/administração & dosagem , Aquaporina 2/metabolismo , Benzamidas/administração & dosagem , Túbulos Renais Coletores/efeitos dos fármacos , Túbulos Renais Coletores/metabolismo , Inibidores da Fosfodiesterase 4/administração & dosagem , 1-Metil-3-Isobutilxantina/administração & dosagem , Animais , Permeabilidade Capilar/efeitos dos fármacos , Ciclopropanos/administração & dosagem , Relação Dose-Resposta a Droga , Medula Renal/efeitos dos fármacos , Medula Renal/metabolismo , Masculino , Fosforilação , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Vasopressinas/metabolismo , Água/metabolismo
6.
Anal Biochem ; 507: 18-20, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27210514

RESUMO

Until now, the low efficiency of current protocols or kits for the differentiation of 3T3-L1 preadipocytes makes it difficult to continue the studies of the cellular and molecular mechanisms in adipocytes. Here we present a productive and highly efficient protocol for the differentiation of 3T3-L1 cells that uses a prolonged treatment with 3-isobutyl-1-methylxanthine (IBMX) during the differentiated process. 3T3-L1 cells of unknown passage +3 and unknown passage +7 treated with a prolonged exposure to IBMX showed significantly increased differentiation efficiency by day 15, in contrast to low levels of differentiation seen with protocols that lacked additional IBMX.


Assuntos
1-Metil-3-Isobutilxantina/farmacologia , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , 1-Metil-3-Isobutilxantina/administração & dosagem , Células 3T3-L1 , Animais , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Camundongos , Relação Estrutura-Atividade , Fatores de Tempo
7.
Gene Expr Patterns ; 20(2): 99-105, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26820751

RESUMO

Homeobox (Hox) genes are involved in body plan of embryo along the anterior-posterior axis. Presence of several Hox genes in white adipose tissue (WAT) and brown adipose tissue (BAT) is indicative of involvement of Hox genes in adipogenesis. We propose that differentiation inducing agents viz. isobutyl-methyl-xanthine (IBMX), indomethacin, dexamethasone (DEX), triiodothyronine (T3) and insulin may regulate differentiation in brown adipose tissue through Hox genes. In vitro culture of brown fat stromalvascular fraction (SVF) in presence or absence of differentiation inducing agents was used for establishing relationship between fat accumulation in differentiated adipocytes and expression of Hox genes. Relative expression of Pref1, UCP1 and Hox genes was determined in different stages of adipogenesis. Presence or absence of IBMX, indomethacin and DEX during differentiation of proliferated pre-adipocytes resulted in marked differences in expression of Hox genes and lipid accumulation. In presence of these inducing agents, lipid accumulation as well as expression of HoxA1, HoxA5, HoxC4 &HoxC8 markedly enhanced. Irrespective of presence or absence of T3, insulin down regulates HoxA10. T3 results in over expression of HoxA5, HoxC4 and HoxC8 genes, whereas insulin up regulates expression of only HoxC8. Findings suggest that accumulation of fat in differentiated adipocytes is linked with expression of Hox genes.


Assuntos
Adipócitos Marrons/metabolismo , Tecido Adiposo/crescimento & desenvolvimento , Proteínas de Homeodomínio/biossíntese , Fosfoproteínas/biossíntese , Fatores de Transcrição/biossíntese , 1-Metil-3-Isobutilxantina/administração & dosagem , Adipócitos Marrons/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Tecido Adiposo/efeitos dos fármacos , Animais , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Dexametasona/administração & dosagem , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Indometacina/administração & dosagem , Insulina/administração & dosagem , Insulina/metabolismo , Camundongos , Tri-Iodotironina/administração & dosagem , Tri-Iodotironina/metabolismo
8.
PLoS One ; 10(5): e0126801, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25965267

RESUMO

Cryopreservation of mature oocytes and embryos has provided numerous benefits in reproductive medicine. Although successful cryopreservation of germinal-vesicle stage (GV) oocytes holds promise for further advances in reproductive biology and clinical embryology fields, reports regarding cryopreservation of immature oocytes are limited. Oocyte survival and maturation rates have improved since vitrification is being performed at the GV stage, but the subsequent developmental competence of GV oocytes is still low. The purpose of this study was to evaluate the effects of supplementation of the maturation medium with cyclic adenosine monophosphate (cAMP) modulators on the developmental competence of vitrified-warmed GV bovine oocytes. GV oocytes were vitrified-warmed and cultured to allow for oocyte maturation, and then parthenogenetically activated or fertilized in vitro. Our results indicate that addition of a cAMP modulator forskolin (FSK) or 3-isobutyl-1-methylxanthine (IBMX) to the maturation medium significantly improved the developmental competence of vitrified-warmed GV oocytes. We also demonstrated that vitrification of GV oocytes led to a decline in cAMP levels and maturation-promoting factor (MPF) activity in the oocytes during the initial and final phases of maturation, respectively. Nevertheless, the addition of FSK or IBMX to the maturation medium significantly elevated cAMP levels and MPF activity during IVM. Taken together, our results suggest that the cryopreservation-associated meiotic and developmental abnormalities observed in GV oocytes may be ameliorated by an artificial increase in cAMP levels during maturation culture after warming.


Assuntos
AMP Cíclico/metabolismo , Fertilização in vitro , Técnicas de Maturação in Vitro de Oócitos , Oócitos/crescimento & desenvolvimento , 1-Metil-3-Isobutilxantina/administração & dosagem , Animais , Bovinos , Colforsina/administração & dosagem , Criopreservação , Feminino , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Vitrificação/efeitos dos fármacos
9.
J Cell Physiol ; 229(12): 2137-41, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24819468

RESUMO

Activating mutations in RAS genes and p21 Ras overactivation are common occurrences in a variety of human tumors. p21 Ras oncoproteins deregulate a number of signaling pathways, dedifferentiating the thyroid cell, and negatively regulating the expression of thyroid specific genes. In rat thyroid cells, Ras oncoproteins inhibit the TSH pathway by reducing PKA activity and thus the expression of thyroid specific genes, while in mouse melanocytes, Ras oncoproteins reduce the αMSH-stimulated cAMP signaling by increasing the expression of the phosphodiesterase-4B. Given these cell-dependent differences, we investigated if and how the TSH/CREB pathway is modulated by Ras oncoprotein in a human thyroid cell line. CREB phosphorylation was stimulated by TSH and forskolin in TAD-2 cells. Ras(V12) expression negatively regulated the TSH-stimulated CREB phosphorylation but was ineffective on forskolin-stimulated CREB phosphorylation. Phosphodiesterase inhibition by IBMX enhanced TSH-stimulated CREB phosphorylation, but did not restore TSH-stimulated CREB phosphorylation inhibited by Ras oncoprotein. These data indicate that Ras oncoprotein disrupts the TSH/CREB pathway, upstream adenylyl cyclase, and highlight the existence of mechanisms of interaction between Ras and the cAMP pathway different in human and in rat thyroid cells.


Assuntos
Adenilil Ciclases/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Tireotropina/metabolismo , 1-Metil-3-Isobutilxantina/administração & dosagem , Animais , Linhagem Celular , AMP Cíclico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Diester Fosfórico Hidrolases/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Ratos , Transdução de Sinais/efeitos dos fármacos , Glândula Tireoide/citologia , Glândula Tireoide/metabolismo
10.
Am J Physiol Heart Circ Physiol ; 304(4): H589-99, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23241319

RESUMO

KCNQ1 and hERG encode the voltage-gated potassium channel α-subunits of the cardiac repolarizing currents I(Ks) and I(Kr), respectively. These currents function in vivo with some redundancy to maintain appropriate action potential durations (APDs), and loss-of-function mutations in these channels manifest clinically as long QT syndrome, characterized by the prolongation of the QT interval, polymorphic ventricular tachycardia, and sudden cardiac death. Previous cellular electrophysiology experiments in transgenic rabbit cardiomyocytes and heterologous cell lines demonstrated functional downregulation of complementary repolarizing currents. Biochemical assays indicated direct, protein-protein interactions between KCNQ1 and hERG may underlie the interplay between I(Ks) and I(Kr). Our objective was to investigate hERG-KCNQ1 interactions in the intact cellular environment primarily through acceptor photobleach FRET (apFRET) experiments. We quantitatively assessed the extent of interactions based on fluorophore location and the potential regulation of interactions by physiologically relevant signals. apFRET experiments established specific hERG-KCNQ1 associations in both heterologous and primary cardiomyocytes. The largest FRET efficiency (E(f); 12.0 ± 5.2%) was seen between ion channels with GFP variants fused to the COOH termini. Acute treatment with forskolin + IBMX or a membrane-permeable cAMP analog significantly and specifically reduced the extent of hERG-KCNQ1 interactions (by 41 and 38%, respectively). Our results demonstrate direct interactions between KCNQ1 and hERG occur in both intact heterologous cells and primary cardiomyocytes and are mediated by their COOH termini. Furthermore, this interplay between channel proteins is regulated by intracellular cAMP.


Assuntos
AMP Cíclico/química , Canais de Potássio Éter-A-Go-Go/química , Canal de Potássio KCNQ1/química , 1-Metil-3-Isobutilxantina/administração & dosagem , Potenciais de Ação/fisiologia , Animais , Células CHO , Células Cultivadas , Colforsina/administração & dosagem , Cricetinae , Cricetulus , AMP Cíclico/agonistas , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go/fisiologia , Feminino , Células HEK293 , Coração/efeitos dos fármacos , Coração/fisiologia , Humanos , Canal de Potássio KCNQ1/fisiologia , Masculino , Inibidores de Fosfodiesterase/administração & dosagem , Coelhos
11.
Exp Dermatol ; 20(7): 568-71, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21410772

RESUMO

We previously demonstrated that exposure to red light (550-670 nm) accelerates epidermal permeability barrier recovery after barrier disruption. Furthermore, we showed that photosensitive proteins, originally found in retina, are also expressed in epidermis. In retina, transducin and phosphodiesterase 6 play key roles in signal transmission. In this study, we evaluate the role of phosphodiesterese 6 in the acceleration by red light of epidermal permeability barrier recovery. Immunohistochemical study and reverse transcription-PCR assays confirmed the expression of both transducin and phosphodiesterase 6 in epidermal keratinocytes. Topical application of 3-isobutyl-1-methylxanthine, a non-specific phosphodiesterase inhibitor, blocked the acceleration of the barrier recovery by red light. Topical application of zaprinast, a specific inhibitor of phosphodiesterases 5 and 6, also blocked the acceleration, whereas T0156, a specific inhibitor of phosphodiesterase 5, had no effect. Red light exposure reduced the epidermal hyperplasia induced by barrier disruption under low humidity, and the effect was blocked by pretreatment with zaprinast. Our results indicate phosphodiesterase 6 is involved in the recovery-accelerating effect of red light on the disrupted epidermal permeability barrier.


Assuntos
Inibidores de Fosfodiesterase/farmacologia , Fototerapia , Pele/metabolismo , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiação , 1-Metil-3-Isobutilxantina/administração & dosagem , 1-Metil-3-Isobutilxantina/farmacologia , Acetona/farmacologia , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/metabolismo , Epiderme/efeitos dos fármacos , Epiderme/metabolismo , Epiderme/patologia , Epiderme/efeitos da radiação , Epiderme/ultraestrutura , Expressão Gênica/genética , Hiperplasia/induzido quimicamente , Hiperplasia/prevenção & controle , Hiperplasia/radioterapia , Masculino , Camundongos , Camundongos Pelados , Naftiridinas/administração & dosagem , Naftiridinas/farmacologia , Permeabilidade , Inibidores de Fosfodiesterase/administração & dosagem , Purinonas/administração & dosagem , Purinonas/farmacologia , Pirimidinas/administração & dosagem , Pirimidinas/farmacologia , Pele/efeitos dos fármacos , Pele/patologia , Pele/efeitos da radiação , Pele/ultraestrutura , Transducina/genética , Transducina/metabolismo , Água/metabolismo
12.
Am J Physiol Lung Cell Mol Physiol ; 300(3): L453-61, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21224213

RESUMO

The combination of dexamethasone, 8-bromo-3'-5'-cyclic adenosine monophosphate, and isobutylmethylxanthine, referred to as DCI, has been reported to optimally induce cell differentiation in fetal lung explants and type II epithelial cells. DCI administration is also known to modulate the expression levels of many genes known to be involved in the facilitation of lung growth. Recently, we found that RNA silencing of thyroid transcription factor 1 (TTF-1) delayed compensatory lung growth. DCI is also known to induce TTF-1 expression in pulmonary epithelial cells. From these findings, we hypothesized that DCI administration may facilitate compensatory lung growth. In the present study, using a postpneumonectomy lung growth model in 9-wk-old male mice, we found that compensatory lung growth was significantly facilitated by airway administration of DCI immediately following left pneumonectomy, as indicated by the increase in the residual right lung dry weight index. TTF-1 expression was significantly elevated by DCI administration, and transient knockdown of TTF-1 attenuated the facilitation of compensatory lung growth by DCI. These results suggested that DCI facilitated compensatory lung growth, at least in part, through the induction of TTF-1. Morphological analyses suggested that DCI administration increased the number of alveoli, made each of them smaller, and produced a net increase in the calculated surface area of the alveoli per volume of lung. The effect of a single administration was maintained during the observation period, which was 28 days. DCI with further modifications may provide the material to potentially augment residual lung function after resection.


Assuntos
1-Metil-3-Isobutilxantina/farmacologia , Envelhecimento/efeitos dos fármacos , AMP Cíclico/farmacologia , Dexametasona/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/crescimento & desenvolvimento , 1-Metil-3-Isobutilxantina/administração & dosagem , Administração Intranasal , Animais , Western Blotting , AMP Cíclico/administração & dosagem , Dexametasona/administração & dosagem , Pulmão/citologia , Pulmão/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Nucleares/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Condicionamento Físico Animal , Pneumonectomia , Pressão , Testes de Função Respiratória , Fator Nuclear 1 de Tireoide , Fatores de Transcrição/metabolismo
13.
J Pharmacol Sci ; 104(4): 311-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17666867

RESUMO

The mechanism by which ibudilast induces vasodilation was examined in isolated endothelium-denuded rat aorta. Ibudilast inhibited the contractions induced by phenylephrine (PE) and high K(+) with decrease of [Ca(2+)](i) level in a concentration-dependent manner, to the same degree. 3-Isobutyl-1-methylxanthine (IBMX) inhibited PE-induced contraction and [Ca(2+)](i) level in a concentration-dependent manner, but it inhibited high K(+)-induced contraction without decrease of [Ca(2+)](i) level. In comparison with IBMX, the increases of cAMP and cGMP contents in ibudilast were much smaller than that of muscle tension. Ibudilast did not inhibit 12-deoxyphorbol 13-isobutyrate (DPB)-induced contraction in the presence of verapamil. Treatment with 30 microM ibudilast inhibited the extracellularly added Ca(2+)-induced muscle tension and increases in [Ca(2+)](i) level during high K(+) depolarization. These results suggested that ibudilast inhibited PE- and high K(+)-induced muscle contractions mainly by the inhibition of [Ca(2+)](i) level in endothelium-denuded rat aorta.


Assuntos
Cálcio/metabolismo , Inibidores de Fosfodiesterase/farmacologia , Piridinas/farmacologia , Vasodilatadores/farmacologia , 1-Metil-3-Isobutilxantina/administração & dosagem , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Citosol/efeitos dos fármacos , Citosol/metabolismo , Relação Dose-Resposta a Droga , Masculino , Contração Muscular/efeitos dos fármacos , Tono Muscular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Fenilefrina , Inibidores de Fosfodiesterase/administração & dosagem , Potássio/metabolismo , Piridinas/administração & dosagem , Ratos , Ratos Wistar , Vasodilatadores/administração & dosagem , Verapamil/administração & dosagem , Verapamil/farmacologia
15.
Endocrine ; 16(2): 97-104, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11887940

RESUMO

The expression and activities of constitutive nitric oxide synthase (cNOS) and inducible nitric oxide synthase (iNOS) in relation to insulin and glucagon secretory mechanisms were investigated in islets isolated from rats subjected to total parenteral nutrition (TPN) for 10 d. TPN is known to result in significantly increased levels of plasma lipids during the infusion time. In comparison with islets from freely fed control rats, islets taken from TPN rats at d 10 displayed a marked decrease in glucose-stimulated insulin release (4.65 +/- 0.45 ng/[islet x h] vs 10.25 +/- 0.65 for controls) (p < 0.001) accompanied by a strong iNOS activity (18.3 +/- 1.1 pmol of NO/[min x mg of protein]) and a modestly reduced cNOS activity (11.3 +/- 3.2 pmol of NO/[min x mg of protein] vs 17.7 +/- 1.7 for controls) (p < 0.01). Similarly, Western blots showed the expression of iNOS protein as well as a significant reduction in cNOS protein in islets from TPN-treated rats. The enhanced NO production, which is known to inhibit glucose-stimulated insulin release, was manifested as a strong increase in the cyclic guanosine 5'-monophosphate content in the islets of TPN-treated rats (1586 +/- 40 amol/islet vs 695 +/- 64 [p < 0.001] for controls). Moreover, the content of cyclic adenosine monophosphate (cAMP) was greatly increased in the TPN islets (80.4 +/- 2.1 fmol/islet vs 42.6 +/- 2.6 [p < 0.001] for controls). The decrease in glucose-stimulated insulin release was associated with an increase in the activity of the secretory pathway regulated by the cAMP system in the islets of TPN-treated rats, since the release of insulin stimulated by the phosphodiesterase inhibitor isobutylmethylxanthine was greatly increased both in vivo after iv injection and after in vitro incubation of isolated islets. By contrast, the release of glucagon was clearly reduced in islets taken from TPN-treated rats (33.5 +/- 1.5 pg/[islet x h] vs 45.5 +/- 2.2 for controls) (p < 0.01) when islets were incubated at low glucose (1.0 mmol/L). The data show that long-term TPN treatment in rats brings about impairment of glucose-stimulated insulin release, that might be explained by iNOS expression and a marked iNOS-derived NO production in the beta-cells. The release of glucagon, on the other hand, is probably decreased by a direct "nutrient effect" of the enhanced plasma lipids. The results also suggest that the islets of TPN-treated rats have developed compensatory insulin secretory mechanisms by increasing the activity of their beta-cell cAMP system.


Assuntos
Hormônios/metabolismo , Ilhotas Pancreáticas/metabolismo , Óxido Nítrico Sintase/metabolismo , Nutrição Parenteral Total , 1-Metil-3-Isobutilxantina/administração & dosagem , 1-Metil-3-Isobutilxantina/farmacologia , Animais , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Glucagon/metabolismo , Glucose/farmacologia , Técnicas In Vitro , Injeções Intravenosas , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Óxido Nítrico Sintase Tipo II , Ratos , Ratos Sprague-Dawley , Valores de Referência
16.
Hum Reprod ; 14(9): 2357-61, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10469710

RESUMO

We evaluated the maturational competence of mouse oocytes reconstructed by the transfer and electrofusion of germinal vesicles (GV) into anuclear cytoplasts of GV stage oocytes (both auto- and hetero-transfers), metaphase II stage oocytes or zygotes. Following in-vitro culture, the maturation rates of the reconstructed oocytes to metaphase II did not significantly differ between auto- and hetero-transfers (40/70 versus 95/144 respectively); these rates also did not differ from those of control oocytes (57/97) which were matured in vitro without micromanipulation and electrofusion. In contrast, when a GV was transferred into an enucleated metaphase II oocyte or a zygote, only a few reconstructed oocytes underwent germinal vesicle breakdown (5/30 and 2/21 respectively); moreover, none reached metaphase II stage. Cytogenetic and immunofluorescence analyses were conducted on hetero-GV oocytes that extruded a first polar body. Each oocyte showed two groups of chromosomes, one in the cytoplast and one in the polar body, as well as a bipolar spindle with twenty univalent chromosomes. Our findings suggest that oocytes reconstructed by GV transfer into a cytoplast of the same developmental stage mature normally in vitro through metaphase II. Such oocytes may be a useful research model to elucidate the cytoplasmic and nuclear mechanisms regulating meiosis and the relationships between meiotic errors and age-related changes in the oocyte.


Assuntos
Citoplasma/fisiologia , Meiose , Técnicas de Transferência Nuclear , Oócitos/ultraestrutura , 1-Metil-3-Isobutilxantina/administração & dosagem , Animais , Núcleo Celular/fisiologia , Feminino , Metáfase , Camundongos , Fatores de Tempo , Zigoto/ultraestrutura
17.
Am J Physiol ; 273(1 Pt 2): R107-12, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9249539

RESUMO

Despite intense study of neurotransmitters mediating hypothalamic controls of food intake, little is known about which second messengers are critical for these mechanisms. To determine whether adenosine 3',5'-cyclic monophosphate (cAMP) might participate in these mechanisms, we injected the membrane-permeant cAMP analog 8-bromo-cAMP (8-BrcAMP) hypothalamically in satiated rats. Injection of 8-BrcAMP (10-100 nmol) into the perifornical (PFH) and lateral hypothalamus (LH) dose dependently stimulated food intake of up to 15.7 g in 2 h. Significantly smaller responses were obtained with thalamic injections. In contrast to the strong stimulatory effects of PFH and LH 8-BrcAMP, cAMP and 8-bromo-guanosine 3',5'-cyclic monophosphate (100 nmol) were ineffective, suggesting a chemically specific, intracellular action. Consistent with this, combined PFH injection of 7-deacetyl-7-O-(N-methylpiperazino)-tau-butyryl-forskolin dihydrochloride and 3-isobutyl-1-methylxanthine, agents that increase endogeneous cAMP, stimulated eating of up to 9.9 g in 2 h. These results demonstrate that increases in PFH/LH cAMP can elicit complex, goal-oriented behavior, suggesting an important role for cAMP in hypothalamic mechanisms stimulating food intake.


Assuntos
8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , AMP Cíclico/fisiologia , Ingestão de Alimentos/fisiologia , Região Hipotalâmica Lateral/fisiologia , Neurônios/fisiologia , Núcleo Hipotalâmico Paraventricular/fisiologia , Sistemas do Segundo Mensageiro/fisiologia , 1-Metil-3-Isobutilxantina/administração & dosagem , 1-Metil-3-Isobutilxantina/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/administração & dosagem , Animais , Colforsina/administração & dosagem , Colforsina/análogos & derivados , Colforsina/farmacologia , GMP Cíclico/administração & dosagem , GMP Cíclico/análogos & derivados , GMP Cíclico/farmacologia , Diterpenos , Região Hipotalâmica Lateral/efeitos dos fármacos , Masculino , Neurônios/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Técnicas Estereotáxicas , Tálamo/efeitos dos fármacos , Tálamo/fisiologia
18.
Gen Pharmacol ; 28(4): 607-10, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9147032

RESUMO

1. The cold (4 degrees C) water swimming stress (CWSS) for 3 min significantly increased the inhibition of the tail-flick response in ICR mice. 2. Pertussis toxin (PTX, 0.05-0.5 microgram) in mice pretreated intrathecally (IT) for 6 days attenuated the inhibition of the tail-flick response induced by CWSS. However, intracerebroventricular (ICV) pretreatment with PTX at the same doses did not affect CWSS-induced inhibition of the tail-flick inhibition. 3. 3-Isobutyl-1-methylxanthine (IBMX, 0.01-1 ng) in mice pretreated IT for 10 min dose-dependently attenuated the inhibition of the tail-flick response induced by CWSS. However, IBMX in mice ICV pretreated ICV at the same doses was not effective in attenuating the CWSS-induced inhibition of the tail-flick response. 4. Neither IT nor ICV pretreatment with cholera toxin (CTX, 0.05-0.5 microgram) for 24 hr affected the inhibition of the tail-flick response induced by CWSS. 5. The ICV or IT injection of PTX, CTX, or IBMX did not affect the basal tail-flick response latency. 6. It is concluded that spinal, but not supraspinal, PTX-sensitive G-proteins and cAMP phosphodiesterase may be involved in the antinociception produced by CWSS. However, neither spinal nor supraspinal CTX-sensitive G-proteins appear to be involved in mediating the antinociception induced by CWSS.


Assuntos
1-Metil-3-Isobutilxantina/administração & dosagem , Toxina da Cólera/administração & dosagem , Proteínas de Ligação ao GTP/fisiologia , Limiar da Dor/fisiologia , Toxina Pertussis , Inibidores de Fosfodiesterase/administração & dosagem , Estresse Fisiológico/fisiopatologia , Fatores de Virulência de Bordetella/administração & dosagem , Animais , Proteínas de Ligação ao GTP/efeitos dos fármacos , Injeções Intraventriculares , Injeções Espinhais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Limiar da Dor/efeitos dos fármacos , Estresse Fisiológico/tratamento farmacológico
19.
Biol Neonate ; 72(5): 305-13, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9395841

RESUMO

We asked whether a single-dose fetal treatment strategy using betamethasone plus either a long-acting beta 2 agonist (formoterol) or betamethasone plus agents that elevate intracellular cyclic adenosine monophosphate (isobutyl methylxanthine and dibutyryl-cyclic adenosine monophosphate) would augment the effects of prenatal betamethasone on postnatal lung function. Preterm lambs were treated with 0.5 mg/kg beta-methasone or betamethasone plus the other agents and delivered 48 h after treatment. The postnatal lung function as assessed by compliance, ventilatory efficiency, and lung volumes at 40 min of age was improved by prenatal betamethasone and improved further by combination treatment, although the augmented responses were not significantly greater than with betamethasone alone. Fatty acid synthase protein and enzymatic activity were not increased by betamethasone or combined treatments, in contrast to responses reported for other animal models. There were no effects of glucocorticoids or the combined treatments on surfactant. Stimulation of the beta 2 agonist system did not augment postnatal lung function significantly above that noted for betamethasone alone with the agents, doses, and duration of exposures tested.


Assuntos
1-Metil-3-Isobutilxantina/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Betametasona/farmacologia , Bucladesina/farmacologia , Etanolaminas/farmacologia , Glucocorticoides/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Inibidores de Fosfodiesterase/farmacologia , Efeitos Tardios da Exposição Pré-Natal , 1-Metil-3-Isobutilxantina/administração & dosagem , Agonistas Adrenérgicos beta/administração & dosagem , Animais , Betametasona/administração & dosagem , Bucladesina/administração & dosagem , Etanolaminas/administração & dosagem , Ácido Graxo Sintases/efeitos dos fármacos , Ácido Graxo Sintases/metabolismo , Feminino , Fumarato de Formoterol , Glucocorticoides/administração & dosagem , Pulmão/enzimologia , Masculino , Inibidores de Fosfodiesterase/administração & dosagem , Gravidez , Proteolipídeos/efeitos dos fármacos , Proteínas Associadas a Surfactantes Pulmonares , Surfactantes Pulmonares/efeitos dos fármacos , Ovinos
20.
J Card Fail ; 2(4): 285-92, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8989643

RESUMO

BACKGROUND: Increased intracellular concentrations of cyclic adenosine monophosphate (AMP) stimulate a positive inotropic and lusitropic response in healthy myocardial tissue. Heart failure results in an attenuated inotropic response to cyclic AMP-dependent agents. This study compares the inotropic versus relaxation response to cyclic AMP-dependent and cyclic AMP-independent agents in myocardium from patients with end-stage heart failure and control patients without heart failure. METHODS AND RESULTS: Fifty-four control and 59 myopathic human ventricular trabeculae, 1 mm or less in diameter were placed in physiologic saline, 2.5 mM Ca2+, and stretched to the length at which maximal isometric force developed at 30 degrees C, 0.33 Hz. Dose-response curves plotted as percentage change from baseline versus concentration of drug were determined for acetylstrophanthidin, isoproterenol, isobutylmethylxanthine, and milrinone. Acetylstrophanthidin, a cyclic AMP-independent agent, showed similar increases in peak tension relative to baseline over the entire dose range tested for both control and myopathic heart muscle; its effect on relaxation of control and failing cardiac muscle was equivalent over the dose range tested. In contrast, the inotropic actions of the cyclic AMP-dependent agents, isoproterenol and the phosphodiesterase inhibitors, were significantly decreased in myopathic muscle compared with control muscle, but effects on relaxation in the control and myopathic groups remained relatively preserved. CONCLUSIONS: A relatively preserved relaxant effect is associated with the cyclic AMP-dependent agents, despite significant diminution of their inotropic effects. Thus, in advanced heart failure, patients may continue to benefit from the lusitropic effects of the cyclic AMP-dependent agents, even when the inotropic effects of these agents are severely attenuated.


Assuntos
1-Metil-3-Isobutilxantina/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Cardiotônicos/farmacologia , Insuficiência Cardíaca/fisiopatologia , Isoproterenol/farmacologia , Contração Miocárdica/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Piridonas/farmacologia , Estrofantidina/análogos & derivados , 1-Metil-3-Isobutilxantina/administração & dosagem , Antagonistas Adrenérgicos beta/administração & dosagem , Adulto , Análise de Variância , Cardiotônicos/administração & dosagem , Técnicas de Cultura , Relação Dose-Resposta a Droga , Insuficiência Cardíaca/patologia , Transplante de Coração , Humanos , Isoproterenol/administração & dosagem , Pessoa de Meia-Idade , Milrinona , Inibidores de Fosfodiesterase/administração & dosagem , Piridonas/administração & dosagem , Valores de Referência , Estrofantidina/administração & dosagem , Estrofantidina/farmacologia
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