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1.
Med Oral Patol Oral Cir Bucal ; 28(2): e131-e139, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36806021

RESUMO

BACKGROUND: The ecoepidemiological panorama of paracoccidioidomycosis (PCM) is dynamic and still ongoing in Brazil. In particular, data about the oral lesions of PCM are barely explored. The aim of this study was to report the clinicopathological features of individuals diagnosed with oral PCM lesions at an oral and maxillofacial pathology service in Rio de Janeiro, Brazil, in the light of a literature review. MATERIAL AND METHODS: A retrospective study was conducted on oral biopsies obtained from 1958 to 2021. Additionally, electronic searches were conducted in PubMed, Embase, Scopus, Web of Science, Latin American and Caribbean Center on Health Sciences Information, and Brazilian Library of Dentistry to gather information from large case series of oral PCM. RESULTS: Ninety-five cases of oral PCM were surveyed. The manifestations were more frequent among males (n=86/90.5%), middle-aged/older adults (n=54/58.7%), and white individuals (n=40/51.9%). The most commonly affected sites were the gingiva/alveolar ridge (n=40/23.4%) and lip/labial commissure (n=33/19.3%); however, one (n=40/42.1%) or multiple sites (n=55/57.9%) could also be affected. In 90 (94.7%) patients, "mulberry-like" ulcerations/moriform appearance were observed. Data from 21 studies (1,333 cases), mostly Brazilian (90.5%), revealed that men (92.4%; male/female: 11.8:1) and individuals in the fifth and sixth decades of life were the most affected (range: 7-89 years), with the gingiva/alveolar ridge, palate, and lips/labial commissure being the sites most frequently affected. CONCLUSIONS: The features of oral PCM lesions are similar to those reported in previous studies from Latin America. Clinicians should be aware of the oral manifestations of PCM, with emphasis on the clinicodemographic aspects and differential diagnoses, especially considering the phenomenon of the emergence of reported cases in rural and/or urban areas of Brazil.


Assuntos
Paracoccidioidomicose , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Idoso , Paracoccidioidomicose/diagnóstico , Paracoccidioidomicose/patologia , Estudos Retrospectivos , Brasil , Gengiva , Palato/patologia
2.
Eur Arch Paediatr Dent ; 23(4): 537-546, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35838891

RESUMO

BACKGROUND: This systematic review and meta-analysis aimed to answer the following question: Are children and adolescents with attention deficit hyperactivity disorder (ADHD) more likely to have gingival or periodontal disease-related outcomes than their non-ADHD peers? METHODS: Searches were conducted in the following databases: Embase, Scopus, Web of Science, and PubMed. Google Scholar and OpenGrey were also verified. Observational studies were included in which children and adolescents with ADHD were compared with their healthy peers in terms of gingival and/or periodontal endpoints. Bias appraisal was performed using the Joann Briggs tool for case-control and cross-sectional studies. Meta-analysis was performed using R language. Results are reported as mean difference (MD) and odds ratio (OR). Statistical analyses were performed in RStudio. RESULTS: A total of 149 records were identified in the searches. Seven studies were included. The meta-analysis showed that children and adolescents with ADHD had a higher mean gingival bleeding index (percentage) than their non-ADHD peers (MD = 11.25; CI = 0.08-22.41; I2 = 73%). There was no difference between groups for plaque index (MD = 4.87; CI = - 2.56 to 12.30; I2 = 63%) and gingivitis (OR = 1.42; CI = 0.22-9.21; I2 = 76%). Regarding the assessment of risk of bias, the major issue found in the articles was the absence of analyses for the control of confounding factors. CONCLUSION: Children and adolescents with ADHD had more gingival bleeding than their non-ADHD peers, but no difference regarding plaque or gingivitis was detected between groups. CLINICAL REGISTRATION: CRD42021258404.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Placa Dentária , Gengivite , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Criança , Humanos
4.
Bone ; 125: 112-121, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31100533

RESUMO

Short-chain fatty acids (SCFAs) exert a variety of immune and metabolic functions by binding to G-protein-coupled receptors, mainly free fatty acid receptor 2 (FFAR2). However, the effects of SCFAs and FFARs on bone remodeling, especially in alveolar bone, have been less explored. In this study, we investigated the influence of the SCFA/FFAR2 axis on alveolar bone. Bone samples from wild-type (WT) and FFAR2-deficient mice (FFAR2-/-) were analyzed using micro-CT, histology and qPCR. WT and FFAR2-/- animals received a high-fiber diet (HFD) reported to increase circulating levels of SCFAs. Additionally, we analyzed the effects of SCFAs and a synthetic FFAR2 agonist, phenylacetamide-1 (CTMB), on bone cell differentiation. The participation of histone deacetylase inhibitors (iHDACs) in the effects of SCFAs was further assessed in vitro. CTMB treatment was also evaluated in vivo during orthodontic tooth movement (OTM). FFAR2-/- mice exhibited deterioration of maxillary bone parameters. Consistent with this, FFAR2-/- mice exhibited a significant increase of OTM and changes in bone cell numbers and in the expression of remodeling markers. The HFD partially reversed bone loss in the maxillae of FFAR2-/- mice. In WT mice, the HFD induced changes in the bone markers apparently favoring a bone formation scenario. In vitro, bone marrow cells from FFAR2-/- mice exhibited increased differentiation into osteoclasts, while no changes in osteoblasts were observed. In line with this, differentiation of osteoclasts was diminished by SCFAs and CTMB. Moreover, CTMB treatment significantly reduced OTM. Pretreatment of osteoclasts with iHDACs did not modify the effects of SCFAs on these cells. In conclusion, SCFAs function as regulators of bone resorption. The effects of SCFAs on osteoclasts are dependent on FFAR2 activation and are independent of the inhibition of HDACs. FFAR2 agonists may be useful to control bone osteolysis.


Assuntos
Ácidos Graxos Voláteis/farmacologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Reabsorção Óssea/tratamento farmacológico , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Receptores Acoplados a Proteínas G/genética , Microtomografia por Raio-X
5.
Int J Oral Maxillofac Surg ; 48(11): 1485-1491, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31088706

RESUMO

This study was performed to evaluate the linear and volumetric effects of a technique for reconstruction of the posterior atrophic mandible, including the final bone gain of the graft, by three-dimensional assessment. Thirteen individuals were recruited into the study and submitted to a total of 15 mandibular autogenous bone block surgeries. Cone beam computed tomography images were obtained at three different times. Bone graft length and thickness, and the volume, height, and width of the graft were measured. Data were compared statistically among the time points using the Friedman test, and cluster analysis was performed to identify the association between the study variables and the resorption rate (α = 0.05). Linear analysis of the width and height of the recipient area at the different time points revealed a statistically significant difference. The final average increase in height was 1.6 mm; all subjects showed an average volume gain of 3.412mm3, and 77% of the subjects showed an average graft resorption of 0.688mm3 construction of three-dimensional vertical defects of the posterior mandible resulted in good healing with minimal complications and minimal bone graft resorption, favouring vertical bone gain.


Assuntos
Aumento do Rebordo Alveolar , Reabsorção Óssea , Transplante Ósseo , Tomografia Computadorizada de Feixe Cônico , Humanos , Mandíbula
6.
Int J Oral Maxillofac Surg ; 48(5): 635-643, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30459066

RESUMO

The aim of this study was to describe 40 cases of acquired oral syphilis (AOS) and to discuss the distribution of demographic characteristics, clinical features, and differential diagnosis of the disease. A retrospective study was conducted covering a 17-year period at a single institution in southern Brazil. Moreover, a literature review was performed through a search of the PubMed database for articles on AOS published between 1955 and March 2018. Data were analyzed descriptively. The predominant group within the case series was male patients in their twenties. The vast majority of cases (92.5%) were in the secondary stage of the disease. The lips were the most commonly affected site, with greyish-white mucous patches and reddish ulcers. In the literature review, the largest number of reported cases came from North America. Male patients in the third and fourth decades of life were most affected. AOS occurred more commonly as mucous patches and ulcers on the tongue and palate. Similarities regarding the distribution by sex, age, and anatomical location were found in the present study when compared to cases reported elsewhere. Clinicians, oral pathologists, and maxillofacial surgeons should familiarize themselves with the variable spectrum of signs and symptoms of AOS in their clinical practice to improve diagnosis and management.


Assuntos
Doenças da Boca , Sífilis , Doenças da Língua , Brasil , Humanos , Masculino , Estudos Retrospectivos
8.
Clin Nephrol ; 73(5): 370-3, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20420797

RESUMO

BACKGROUND AND AIM: For effective dietary phosphorous (P) binding, patients are recommended to chew lanthanum tablets completely before swallowing, with or immediately after meals. However, some patients are unable to chew the tablets. It is not known if crushing the tablets prior to taking them with food is as efficacious as chewing them. This study was conducted to compare the efficacy of chewed vs. crushed lanthanum on P binding. METHODS: 12 healthy subjects were randomized and crossed-over to receive: (A) a standardized meal containing 1 g (32 mmol) of elemental P; (B) a single 1 g oral dose of lanthanum, chewed and taken with the standardized meal; (C) a single 1 g oral dose of lanthanum, crushed into a fine powder using a pestle and mortar, mixed with applesauce, and taken with the standardized meal. Blood and urine samples were collected from baseline to 8 hours after meal completion. The changes in serum P, urinary P excretion and fractional excretion of P (FePi) were compared among treatment arms using ANOVA. RESULTS: Co-administration of lanthanum with meal resulted in a smaller increase in serum P, compared with meal alone (p < 0.05). The smaller increase in serum P was similar for both chewed and crushed lanthanum. The amount of P excreted and FePi were also lower when chewed or crushed lanthanum was administered with meal, compared with meal alone (p = n.s. and p < 0.05, respectively). CONCLUSION: Both chewed and crushed lanthanum are effective in lowering P absorption after a dietary P load.


Assuntos
Lantânio/administração & dosagem , Lantânio/farmacocinética , Mastigação , Fósforo na Dieta/metabolismo , Administração Oral , Adulto , Estudos Cross-Over , Feminino , Alimentos , Humanos , Masculino , Pós , Valores de Referência , Comprimidos , Adulto Jovem
9.
Braz. j. med. biol. res ; 42(12): 1191-1195, Dec. 2009. ilus
Artigo em Inglês | LILACS | ID: lil-532304

RESUMO

The objective of the present study was to assess the effects of the immunosuppressant rapamycin (Rapamune®, Sirolimus) on both resistance vessel responsiveness and atherosclerosis in apolipoprotein E-deficient 8-week-old male mice fed a normal rodent diet. Norepinephrine (NE)-induced vasoconstriction, acetylcholine (ACh)- and sodium nitroprusside (SNP)-induced vasorelaxation of isolated mesenteric bed, and atherosclerotic lesions were evaluated. After 12 weeks of orally administered rapamycin (5 mg·kg-1·day-1, N = 9) and compared with untreated (control, N = 9) animals, rapamycin treatment did not modify either NE-induced vasoconstriction (maximal response: 114 ± 4 vs 124 ± 10 mmHg, respectively) or ACh- (maximal response: 51 ± 8 vs 53 ± 5 percent, respectively) and SNP-induced vasorelaxation (maximal response: 73 ± 6 vs 74 ± 6 percent, respectively) of the isolated vascular mesenteric bed. Despite increased total cholesterol in treated mice (982 ± 59 vs 722 ± 49 mg/dL, P < 0.01), lipid deposition on the aorta wall vessel was significantly less in rapamycin-treated animals (37 ± 12 vs 68 ± 8 µm² x 10³). These results indicate that orally administered rapamycin is effective in attenuating the progression of atherosclerotic plaque without affecting the responsiveness of resistance vessels, supporting the idea that this immunosuppressant agent might be of potential benefit against atherosclerosis in patients undergoing therapy.


Assuntos
Animais , Masculino , Camundongos , Apolipoproteínas E/deficiência , Aterosclerose/prevenção & controle , Endotélio Vascular/efeitos dos fármacos , Imunossupressores/farmacologia , Sirolimo/farmacologia , Resistência Vascular/efeitos dos fármacos , Administração Oral , Camundongos Knockout , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
10.
Braz J Med Biol Res ; 42(12): 1191-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19893993

RESUMO

The objective of the present study was to assess the effects of the immunosuppressant rapamycin (Rapamune, Sirolimus) on both resistance vessel responsiveness and atherosclerosis in apolipoprotein E-deficient 8-week-old male mice fed a normal rodent diet. Norepinephrine (NE)-induced vasoconstriction, acetylcholine (ACh)- and sodium nitroprusside (SNP)-induced vasorelaxation of isolated mesenteric bed, and atherosclerotic lesions were evaluated. After 12 weeks of orally administered rapamycin (5 mg.kg-1.day-1, N = 9) and compared with untreated (control, N = 9) animals, rapamycin treatment did not modify either NE-induced vasoconstriction (maximal response: 114 +/- 4 vs 124 +/- 10 mmHg, respectively) or ACh- (maximal response: 51 +/- 8 vs 53 +/- 5%, respectively) and SNP-induced vasorelaxation (maximal response: 73 +/- 6 vs 74 +/- 6%, respectively) of the isolated vascular mesenteric bed. Despite increased total cholesterol in treated mice (982 +/- 59 vs 722 +/- 49 mg/dL, P < 0.01), lipid deposition on the aorta wall vessel was significantly less in rapamycin-treated animals (37 +/- 12 vs 68 +/- 8 microm(2) x 10(3)). These results indicate that orally administered rapamycin is effective in attenuating the progression of atherosclerotic plaque without affecting the responsiveness of resistance vessels, supporting the idea that this immunosuppressant agent might be of potential benefit against atherosclerosis in patients undergoing therapy.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/prevenção & controle , Endotélio Vascular/efeitos dos fármacos , Imunossupressores/farmacologia , Sirolimo/farmacologia , Resistência Vascular/efeitos dos fármacos , Administração Oral , Animais , Masculino , Camundongos , Camundongos Knockout , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
11.
Clin Nephrol ; 68(1): 10-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17703830

RESUMO

AIMS: This 1-year double-blind, placebo-controlled, multicenter study evaluated the long-term safety and efficacy of cinacalcet for the treatment of secondary hyperparathyroidism in patients receiving hemodialysis. METHOD: Patients were randomly assigned in a 1:1 ratio to cinacalcet or control treatment groups. The initial dose of cinacalcet (or matching placebo) was 30 mg. Doses were titrated every 3 or 4 weeks based on the intact parathyroid hormone (iPTH) response and safety profile. Sequential doses included 30, 60, 90, 120 and 180 mg/d. Phosphate binders and vitamin D sterols were adjusted per protocol as needed to control levels of calcium and phosphorus. Efficacy and safety were compared between treatment groups among patients who completed the study (52 total weeks of treatment). Reasons for withdrawal are presented for patients who did not complete the study. RESULTS: A total of 210 patients completed 52 weeks of double-blinded treatment with cinacalcet (n = 99) or placebo (n = 111). Over the last 6 months of the study, a greater proportion of patients in the cinacalcet group than the control group achieved an iPTH level < or = 250 pg/ml (61.6 vs. 9.9%, p < 0.001) or a > or = 30% decrease in iPTH from baseline (81.8 vs. 21.6%, p < 0.001). Mean iPTH levels decreased by -47.8% in the cinacalcet group and increased by +12.9% in the control group. Mean percentage changes in other laboratory values in the cinacalcet and control groups included the following: serum calcium -6.5 vs. +0.9% (p < 0.001), serum phosphorus -3.6 vs. -1.1% (p = 0.465), and Ca x P -9.9 vs. -0.3% (p = 0.006). The most commonly reported adverse events related to study drug by the investigators included nausea (13% cinacalcet, 5% control), investigator-reported hypocalcemia (11% cinacalcet, 1% control), vomiting (9% cinacalcet, 2% control), dyspepsia (5% cinacalcet, 4% control), and diarrhea (5% cinacalcet, 2% control). CONCLUSIONS: Treatment with cinacalcet is a safe and effective therapy for long-term control of secondary hyperparathyroidism. 1-year therapy with cinacalcet was associated with sustained, clinically significant reductions in calcium, Ca x P and iPTH which allowed a greater percentage of patients to achieve NKF-KDOQI target goals for PTH and Ca x P.


Assuntos
Hiperparatireoidismo Secundário/tratamento farmacológico , Naftalenos/uso terapêutico , Diálise Renal , Cinacalcete , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
12.
J Membr Biol ; 199(1): 39-49, 2004 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15366422

RESUMO

The sodium bicarbonate cotransporter (NBC1) mediates bicarbonate reabsorption in the renal proximal tubule. NBC1 activity is stimulated by 10% CO2, however, the mechanism is poorly understood. Here, we examined the mechanism of NBC1 regulation by 10% CO2 using an immortalized human proximal tubule cell line (HK2). In cells exposed to 10% CO2, the cotransporter activity (measured as deltapH/min) increased within minutes and this increase was maintained for 6 to 24 h. Early NBC1 stimulation was accompanied by increased NBC1 phosphorylation. Basolateral membrane NBC1 protein increased by 30 min and reached a maximum at 6 h. Increased NBC activity at 6 h was accounted for by increased NBC exocytosis to the basolateral membrane and not by decreased endocytosis. Latruncullin B (an actin cytoskeleton inhibitor) did not prevent CO2-induced stimulation, while nocodazole (a microtubule-disrupting agent) abrogated the stimulatory effect of 10% CO2. A significant increase in NBC1 mRNA expression level was observed at 6 h and maintained for 24 h. Total NBC1 protein increased at 12 to 24 h with 10% CO2 incubation and this effect was blocked by cycloheximide. In summary, the present study demonstrates that early activation of NBC1 activity by 10% CO2 was mediated by NBC1 phosphorylation. The stimulation of cotransporter activity observed at 6 h was due to exocytosis, while the late effect starting from 12 h was accounted for by increased protein synthesis.


Assuntos
Actinas/fisiologia , Bicarbonatos/metabolismo , Dióxido de Carbono/farmacologia , Exocitose/fisiologia , Túbulos Renais Proximais/metabolismo , Simportadores de Sódio-Bicarbonato/metabolismo , Actinas/efeitos dos fármacos , Células Cultivadas , Cicloeximida/farmacologia , Exocitose/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Nocodazol/farmacologia , Fosforilação , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/metabolismo
13.
Am J Nephrol ; 23(6): 438-41, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14583662

RESUMO

BACKGROUND: The clinical significance of a trace protein reading on urinalysis is unclear, and such a result is often ignored by the clinician. METHODS: We examined 185 samples of urine with trace proteinuria by both Chemstrips and sulfosalicylic acid testing, and compared the results with those of urinary albumin and total protein concentrations. RESULTS: Taking for the purposes of this study an arbitrary upper limit of normal of 20 mg/l for albumin and 100 mg/l for total protein concentration, we found abnormal albumin excretion in 87% and abnormal total protein excretion in 88% of trace samples. In this study, a negative urinalysis for protein excluded microalbuminuria in 87% and proteinuria in 78% of cases. CONCLUSION: Qualitative testing for protein by urinalysis has a high sensitivity and specificity for diagnosing or ruling out microalbuminuria. Trace proteinuria usually means microalbuminuria; negative proteinuria tends to rule it out.


Assuntos
Albuminúria/diagnóstico , Nefropatias/diagnóstico , Benzenossulfonatos , Humanos , Proteinúria/diagnóstico , Fitas Reagentes , Salicilatos , Sensibilidade e Especificidade , Urinálise/métodos
14.
Int J Artif Organs ; 26(6): 484-90, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12866654

RESUMO

PURPOSE: The efficacy of the vitamin D analog paricalcitol has mainly been shown in short-term studies. There are limited data regarding long-term treatment with this agent. This purpose of this study was to determine long-term effects of paricalcitol therapy on parathyroid hormone (PTH) suppression and serum levels of calcium, phosphorus and calcium-phosphorus product (Ca x P). PATIENTS AND METHODS: Patients who received paricalcitol for > or = 3 months had the following data collected: demographics, drug dosage, serum PTH, corrected serum calcium concentration, serum phosphorus concentrations and serum Ca x P values. RESULTS: Sixteen patients received paricalcitol for a mean of 18 months. The mean +/- SD dose of paricalcitol was 0.13 +/- 0.12 mcg/kg. The mean +/- SD pre-paricalcitol serum PTH concentration was 705 +/- 423 pg/mL. PTH concentration did not change significantly over the duration of treatment (mean +/- SD: 821 +/- 480 pg/mL). The number of patients who had at least one corrected serum calcium concentration > or = 11.5 mg/dL, one serum phosphorus concentration > or = 6.5 mg/dL, or one Ca x P level > or = 70 were 75%, 94% and 82%, respectively. Hypercalcemia and elevated Ca x P value resulted in a mean of 17% of doses being withheld during therapy. CONCLUSION: During the study, PTH was not adequately suppressed by paricalcitol. This was primarily attributed to withholding paricalcitol doses due to elevated serum calcium and Ca x P levels.


Assuntos
Ergocalciferóis/uso terapêutico , Hiperparatireoidismo Secundário/tratamento farmacológico , Diálise Renal , Adulto , Cálcio , Feminino , Humanos , Hipercalcemia , Hiperparatireoidismo Secundário/etiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo , Fósforo , Distúrbios do Metabolismo do Fósforo
15.
J Membr Biol ; 191(2): 141-8, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-12533781

RESUMO

The basolateral Na+/HCO3- cotransporter (NBC) is the major pathway for bicarbonate reabsorption in the renal proximal tubule cells. The cotransporter activity is enhanced by 10% CO2. Phosphatidylinositol 3-kinase (PI3K) has been shown to regulate the function and trafficking of cellular proteins by promoting their translocation to the plasma membrane. Therefore, we sought to examine the role of PI3K in CO2-mediated stimulation of NBC activity in OK cells. Our studies showed that wortmannin, a well-characterized PI3K inhibitor, had no effect on baseline NBC activity but prevented the stimulatory effect of 10% CO2. This effect was concentration-dependent and time-dependent. Another inhibitor of PI3K, LY294002, also prevented the CO2-mediated increase in NBC activity. CO2 stimulation of the cotransporter was paralleled by an increase in PI3K enzyme activity and this effect was blocked by wortmannin. Biotinylation studies also showed that 10% CO2 increased the immunoreactive NBC in the basolateral membranes and this was prevented by wortmannin. We previously showed that 10% CO2 stimulation of NBC activity involves the Src family kinase pathway. In the current studies, CO2 stimulation significantly increased Src phosphorylation and this effect was abrogated by wortmannin. In summary, CO2 stimulation of NBC is mediated at least in part by increased immunoreactive NBC protein in the basolateral membrane, a process which requires the interaction of PI3K with Src family kinase.


Assuntos
Acidose Respiratória/metabolismo , Dióxido de Carbono/farmacologia , Rim/metabolismo , Fosfatidilinositol 3-Quinases/fisiologia , Simportadores de Sódio-Bicarbonato/fisiologia , Androstadienos/farmacologia , Animais , Células Cultivadas , Cromonas/farmacologia , Rim/efeitos dos fármacos , Morfolinas/farmacologia , Gambás , Inibidores de Fosfoinositídeo-3 Quinase , Simportadores de Sódio-Bicarbonato/efeitos dos fármacos , Wortmanina
16.
J Membr Biol ; 187(2): 135-45, 2002 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12029370

RESUMO

Angiotensin II (AII) plays an important role in renal proximal tubular acidification via the costimulation of basolateral Na/HCO3 cotransporter (NBC) and apical Na/H exchanger (NHE) activities. These effects are mediated by specific G protein-coupled AII receptors, but their corresponding downstream effectors are incompletely defined. Src family tyrosine kinases (SFKs) contribute to the regulation of both transport activities by a variety of stimuli and are coupled to classic mitogen-activated protein kinase (MAPK) pathway activation in this cell type. We therefore examined these signaling intermediates for involvement in AII-stimulated NBC activity in cultured proximal tubule cells. Subpressor concentrations of AII (0.1 nM) increased NBC activity within minutes, and this effect was abrogated by selective antagonism of AT1 angiotensin receptors, SFKs, or the classic MAPK pathway. AII directly activated Src, as well as the proximal (Raf) and distal (ERK) elements of the classic MAPK module, and the activation of Src was prevented by AT1 receptor antagonism. An associated increase in basolateral membrane NBC1 content is compatible with the involvement of this proximal tubule isoform in these changes. We conclude that AII stimulation of the AT1 receptor increases NBC activity via sequential activation of SFKs and the classic MAPK pathway. Similar requirements for SFK/MAPK coupling in both cholinergic and acidotic costimulation of NBC and NHE activities suggest a central role for these effectors in the coordinated regulation of epithelial transport by diverse stimuli.


Assuntos
Angiotensina II/metabolismo , Túbulos Renais Proximais/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Simportadores de Sódio-Bicarbonato/metabolismo , Quinases da Família src/metabolismo , Angiotensina II/farmacologia , Animais , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Concentração de Íons de Hidrogênio , Túbulos Renais Proximais/efeitos dos fármacos , Gambás , Sensibilidade e Especificidade , Transdução de Sinais/fisiologia
18.
Am J Physiol Renal Physiol ; 280(5): F844-50, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11292627

RESUMO

Cholinergic agents are known to affect the epithelial transport of H2O and electrolytes in the kidney. In proximal tubule cells, cholinergic agonists increase basolateral Na-HCO(3) cotransport activity via M(1) muscarinic receptor activation. The signaling intermediates that couple these G protein-coupled receptors to cotransporter activation, however, are not well defined. We therefore sought to identify distal effectors of muscarinic receptor activation that contribute to increased NBC activity in cultured proximal tubule cells. As demonstrated previously for acute CO2-regulated cotransport activity, we found that inhibitors of Src family kinases (SFKs) or the classic mitogen-activated protein kinase (MAPK) pathway prevented the stimulation of NBC activity by carbachol. The ability of carbachol to activate Src, as well as the proximal (Raf) and distal [extracellular signal-regulated kinases 1 and 2 (ERK1/2)] elements of the classic MAPK module, was compatible with these findings. Cholinergic stimulation of ERK1/2 activity was also completely prevented by overexpression of a dominant negative mutant of Ras (N17-Ras). Taken together, these findings suggest a requirement for the sequential activation of SFKs, Ras, and the classic MAPK pathway [Raf-->MAPK/ERK kinase (MEK)-->ERK]. These findings provide important insights into the molecular mechanisms underlying cholinergic regulation of NBC activity in renal epithelial cells. They also suggest a specific mechanism whereby cholinergic stimulation of the kidney can contribute to pH homeostasis.


Assuntos
Proteínas de Transporte/metabolismo , Células Epiteliais/metabolismo , Genes ras/genética , Túbulos Renais Proximais/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Agonistas Muscarínicos/farmacologia , Gambás/metabolismo , Receptores Muscarínicos/efeitos dos fármacos , Quinases da Família src/metabolismo , Animais , Carbacol/farmacologia , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Túbulos Renais Proximais/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Proto-Oncogênicas c-raf/metabolismo , Transdução de Sinais/fisiologia , Simportadores de Sódio-Bicarbonato , Quinases da Família src/antagonistas & inibidores
19.
Kidney Int ; 59(3): 876-82, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231342

RESUMO

BACKGROUND: Relaxin, a hormone of the insulin-growth factor family, promotes collagen remodeling. In rodent models of pulmonary and dermal fibrosis, relaxin reduced interstitial fibrosis. To study relaxin's effect in renal disease, we used the experimental bromoethylamine (BEA) model that leads to severe renal interstitial fibrosis, a decrease in glomerular filtration rate, and albuminuria at one month. METHODS: Rats were injected with BEA one week prior to implantation of an osmotic pump delivering relaxin (2 microg/hour) or vehicle continuously for 28 days. RESULTS: BEA caused a significant decrease in creatinine clearance, which was partially prevented by relaxin. In the relaxin-treated BEA rats, serum creatinine was normal, and albumin excretion was slightly decreased. By morphometric measurement, relaxin administration was associated with a significant decrease in interstitial fibrosis at the corticomedullary junction. This was accompanied by a decrease in the number of ED-1 positive cells (an index of macrophage infiltration) and in the intensity of immunohistochemical staining for transforming growth factor-beta. This antifibrotic effect of relaxin did not appear to be mediated by systemic hemodynamic changes since the mean arterial pressure was not significantly different among the groups. CONCLUSIONS: Relaxin may have a useful application in decreasing interstitial fibrosis and thereby slowing the progression of renal disease.


Assuntos
Nefropatias/tratamento farmacológico , Nefropatias/patologia , Rim/patologia , Relaxina/uso terapêutico , Animais , Creatinina/metabolismo , Progressão da Doença , Etilaminas , Fibrose , Córtex Renal/efeitos dos fármacos , Córtex Renal/patologia , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Medula Renal/efeitos dos fármacos , Medula Renal/patologia , Túbulos Renais/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta/metabolismo
20.
Kidney Blood Press Res ; 24(1): 39-43, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11174005

RESUMO

This study was undertaken to determine whether angiotensin receptor blockers are as renoprotective as angiotensin-converting enzyme inhibitors in an experimental model of chronic interstitial renal disease. Groups of rats received one of the following treatments for 1 week: (1) enalapril, (2) diltiazem, (3) a cocktail of hydralazine, reserpine, and hydrochlorothiazide, or (4) irbesartan (an AT1 antagonist). The animals were injected with bromoethylamine (200 mg/kg), and antihypertensive treatment continued for 1 month. All drugs were effective in lowering the mean arterial pressure. The bromoethylamine-treated rats developed albuminuria and sustained a 40-50% decrease in creatinine clearance. Enalapril and irbesartan reduced albuminuria, but only enalapril partially prevented the decline in creatinine clearance and lowered the number of ED-1-positive cells. Diltiazem and cocktail had no effect on proteinuria, creatinine clearance, or ED-1 cells. In this experimental model, the effects of enalapril and irbesartan were not identical. Both drugs reduced proteinuria, but enalapril was more effective in protecting the renal function. The fact that the AT1 antagonist protected against albuminuria but did not affect the clearance of creatinine implies that the results seen with angiotensin-converting enzyme inhibition may be in part due to an effect on angiotensin II via AT2 receptor blockade or through an effect on bradykinin.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Compostos de Bifenilo/farmacologia , Enalapril/farmacologia , Necrose Papilar Renal/tratamento farmacológico , Tetrazóis/farmacologia , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Compostos de Bifenilo/uso terapêutico , Enalapril/uso terapêutico , Irbesartana , Necrose Papilar Renal/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Tetrazóis/uso terapêutico
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