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1.
BMC Pulm Med ; 19(1): 223, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31771541

RESUMO

BACKGROUND: The CAnadian REgistry for Pulmonary Fibrosis (CARE-PF) is a multi-center, prospective registry designed to study the natural history of fibrotic interstitial lung disease (ILD) in adults. The aim of this cross-sectional sub-study was to describe the baseline characteristics, risk factors, and comorbidities of patients enrolled in CARE-PF to date. METHODS: Patients completed study questionnaires and clinical measurements at enrollment and each follow-up visit. Environmental exposures were assessed by patient self-report and comorbidities by the Charlson Comorbidity Index (CCI). Baseline characteristics, exposures, and comorbidities were described for the overall study population and for incident cases, and were compared across ILD subtypes. RESULTS: The full cohort included 1285 patients with ILD (961 incident cases (74.8%)). Diagnoses included connective tissue disease-associated ILD (33.3%), idiopathic pulmonary fibrosis (IPF) (24.7%), unclassifiable ILD (22.3%), chronic hypersensitivity pneumonitis (HP) (7.5%), sarcoidosis (3.2%), non-IPF idiopathic interstitial pneumonias (3.0%, including idiopathic nonspecific interstitial pneumonia (NSIP) in 0.9%), and other ILDs (6.0%). Patient-reported exposures were most frequent amongst chronic HP, but common across all ILD subtypes. The CCI was ≤2 in 81% of patients, with a narrow distribution and range of values. CONCLUSIONS: CTD-ILD, IPF, and unclassifiable ILD made up 80% of ILD diagnoses at ILD referral centers in Canada, while idiopathic NSIP was rare when adhering to recommended diagnostic criteria. CCI had a very narrow distribution across our cohort suggesting it may be a poor discriminator in assessing the impact of comorbidities on patients with ILD.


Assuntos
Alveolite Alérgica Extrínseca/epidemiologia , Exposição Ambiental , Fibrose Pulmonar Idiopática/epidemiologia , Doenças Pulmonares Intersticiais/epidemiologia , Sistema de Registros , Adulto , Idoso , Canadá/epidemiologia , Comorbidade , Doenças do Tecido Conjuntivo/complicações , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Inquéritos e Questionários
2.
Heart Lung ; 47(3): 264-268, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29627072

RESUMO

RATIONALE: Prior work has described the experience of caregiving in idiopathic pulmonary fibrosis, but the effect on caregivers in interstitial lung disease (ILD) has not been explored. OBJECTIVES: Describe the burden, resilience, and health related quality of life (HRQoL) of caregivers of people with ILD. METHODS: In a mixed methods study, ILD caregivers completed questionnaires and participated in focus groups. A qualitative thematic analysis of the focus group transcripts was conducted. RESULTS: Thirty seven caregivers completed the survey, and 15 participated in the focus groups. 65% were female; the average age was 66 (SD = 13). The mean Short Form-36 role emotional and mental health scores were 18 (SD = 4) and 46 (SD = 7). The focus groups identified 4 major themes: emotional burden, changes in relationship, coping strategies, and unmet needs of caregivers. CONCLUSIONS: Caregiving for patients with ILD significantly impairs HRQoL, particularly, emotional health. Increasing resources could improve the caregiving experience in ILD.


Assuntos
Cuidadores/psicologia , Cuidadores/estatística & dados numéricos , Doenças Pulmonares Intersticiais/terapia , Adaptação Psicológica , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
3.
Ann Bot ; 109(2): 365-77, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22147545

RESUMO

BACKGROUND AND AIMS: There is increasing evidence that suppressed bud burst and thus epicormic shoot emergence (sprouting) are controlled by water-carbohydrate supplies to entire trees and buds. This direct evidence is still lacking for oak. In other respects, recent studies focused on sessile oak, Quercus petraea, have confirmed the important constraints of sprouting by epicormic ontogeny. The main objective of this paper was thus to provide provisional confirmation of the water-carbohydrate control and direct evidence of the ontogenic constraints by bringing together results already published in separate studies on water status and distribution of carbohydrates, and on accompanying vegetation and epicormics, which also quantify epicormic ontogeny. METHODS: This paper analyses results gained from a sessile oak experiment in which part of the site was free from fairly tall, dense accompanying vegetation. This experiment was initially focused on stand water status and more recently on the carbohydrate distribution of dominant trees. External observations of the epicormic composition and internal observations with X-ray computer tomography were undertaken on 60 and six trees, respectively. KEY RESULTS: Sprouting was more intense in the part of the stand free from accompanying vegetation and on upper trunk segments. A clear effect of epicormic ontogeny was demonstrated as well: the more epicormics a trunk segment bears, the more chances it had to bear sprouts. CONCLUSIONS: These results indirectly infer water-carbohydrate control and show direct evidence of constraints by epicormic ontogeny. These results have far-reaching consequences related to the quantification of all functions fulfilled by any type of epicormic structure in any part of the tree.


Assuntos
Quercus/crescimento & desenvolvimento , Quercus/metabolismo , Água/metabolismo , Transporte Biológico , Metabolismo dos Carboidratos , França , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo
4.
Adv Med Sci ; 55(1): 1-15, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20439184

RESUMO

Studies on the control of pancreatic secretion in humans of all ages have been a difficult task over the years because of patients' availability and ethic committee rules. Nevertheless, studies were performed and the objectives of this review are to summarize our knowledge on the development of secretory process in newborns, on the different phases of the pancreatic responses to a meal, on the pancreatic responses to the different components of the diet, on the mechanisms involved in the control of the pancreatic responses, and finally on the receptors involved in these controls.


Assuntos
Pâncreas/metabolismo , Hormônios Gastrointestinais/metabolismo , Humanos , Recém-Nascido , Período Pós-Prandial
5.
J Dairy Sci ; 92(3): 1038-49, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19233797

RESUMO

In milk-fed calves, the effects of sodium-butyrate (Na-butyrate) to replace flavomycin on growth performance and some mechanisms involved were studied. Pancreatic and intestinal morphology, digestive enzyme activities, plasma gut regulatory peptide concentrations, and expression of their receptors in the gastrointestinal tract were measured. Gastrointestinal tract defense systems were examined by measuring protein levels of 2 heat-shock proteins (HSP27 and HSP70). The calves were randomly allocated into 2 groups fed the same basic diet with flavomycin as an antimicrobial growth promoter or with Na-butyrate (3 g/kg of dry matter). Sodium-butyrate disappeared quickly in the upper gut and was not found in circulating blood. Supplementation with Na-butyrate enhanced growth rate and improved feed conversion into body weight gain compared with the flavomycin group. Supplementation with Na-butyrate was likely associated with an improvement in efficacy of the gastrointestinal tract digestive capacities expressed by enhanced production of digestive enzymes and increased absorptive capacities in the upper small intestine. The effects could have been controlled by insulin-like growth factor-1 but probably not by any of the cholecystokinin/gastrin peptide family. Concentrations of HSP27 and HSP70 were increased in stomach and colon of calves receiving Na-butyrate, thereby assuring protection of cells with intensive metabolism (chaperone function). In conclusion, beneficial effects of Na-butyrate on maturation of gastrointestinal functions were shown in milk-fed calves and may be applied to young mammals of other species.


Assuntos
Butiratos/farmacologia , Bovinos/crescimento & desenvolvimento , Trato Gastrointestinal/efeitos dos fármacos , Substâncias de Crescimento/farmacologia , Crescimento e Desenvolvimento/efeitos dos fármacos , Substitutos do Leite , Animais , Antibacterianos/farmacologia , Bambermicinas/farmacologia , DNA/análise , Trato Gastrointestinal/crescimento & desenvolvimento , Trato Gastrointestinal/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Mucosa Intestinal/química , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/enzimologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/enzimologia , Proteínas/análise , Distribuição Aleatória , Receptores da Colecistocinina
6.
Adv Med Sci ; 53(2): 99-118, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18930876

RESUMO

This review article has for major objective to summarize the old and latest developments on the hormonal controls of pancreatic growth. The article deals with hormonal controls during the fetal, neonatal and adult periods of pancreas development, growth and regeneration. During the fetal period, comparisons were made between studies performed with pancreatic explants and those designed in vivo. After birth, the effects of glucocorticoids, thyroxine, gastrin, bombesin, secretin, cholecystokinin alone or with secretin are reported. In the adults, similar studies were reported on hormones with addition of the effects of neuropeptides, the cell types targeted by hormones and the hormonal control after pancreatectomy and pancreatitis.


Assuntos
Hormônios/fisiologia , Pâncreas/embriologia , Pâncreas/crescimento & desenvolvimento , Adulto , Desenvolvimento Fetal/fisiologia , Humanos , Recém-Nascido , Pancreatectomia , Regeneração/fisiologia
7.
Nutr Res Rev ; 19(2): 254-83, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19079889

RESUMO

The aim of the present review is to synthesise and summarise our recent knowledge on the involvement of cholecystokinin (CCK) and gastrin peptides and their receptors in the control of digestive functions and more generally their role in the field of nutrition in mammals. First, we examined the release of these peptides from the gut, focusing on their molecular forms, the factors regulating their release and the signalling pathways mediating their effects. Second, general physiological effects of CCK and gastrin peptides are described with regard to their specific receptors and the role of CCK on vagal mucosal afferent nerve activities. Local effects of CCK and gastrin in the gut are also reported, including gut development, gastrointestinal motility and control of pancreatic functions through vagal afferent pathways, including NO. Third, some examples of the intervention of the CCK and gastrin peptides are exposed in diseases, taking into account intervention of the classical receptor subtypes (CCK1 and CCK2 receptors) and their heterodimerisation as well as CCK-C receptor subtype. Finally, applications and future challenges are suggested in the nutritional field (performances) and in therapy with regards to the molecular forms or in relation with the type of receptor as well as new techniques to be utilised in detection or in therapy of disease. In conclusion, the present review underlines recent developments in this field: CCK and gastrin peptides and their receptors are the key factor of nutritional aspects; a better understanding of the mechanisms involved may increase the efficiency of the nutritional functions and the treatment of abnormalities under pathological conditions.

10.
J Dent Res ; 83(5): 429-33, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15111638

RESUMO

The periodontal pathogen Porphyromonas gingivalis (Pg) is a potent inducer of the production of pro-inflammatory cytokines by neutrophils, monocytes, and macrophages, and can desensitize immune cells in vitro and in vivo. We analyzed the ability of Pg lipopolysaccharide (LPS) to induce endotoxin tolerance. Treatment of dendritic cells (DC), the human macrophage cell line THP-1, and monocytes (antigen-presenting cells, APC) with Pg.LPS inhibited APC maturation assessed by CD80 and CD86 expression, and inhibited chemokine (CCL3 and CCL5) production. Pre-treatment with glucocorticoids (GC) and interleukin-10 (IL-10) abolished the effect of Pg.LPS on CD80, CD83, and CD86, and on CCL3 and CCL5 production. We also showed that Pg.LPS enhanced the tolerogenic properties of APCs and up-regulated ILT-3 and B7-H1 expression.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Tolerância Imunológica/imunologia , Doenças Periodontais/microbiologia , Porphyromonas gingivalis/imunologia , Antígenos CD/análise , Antígeno B7-1/análise , Antígeno B7-2 , Linhagem Celular , Células Cultivadas , Quimiocinas CC/análise , Células Dendríticas/imunologia , Endotoxinas/farmacologia , Glucocorticoides/farmacologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulinas/análise , Interleucina-10/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Glicoproteínas de Membrana/análise , Monócitos/imunologia , Neutrófilos/imunologia , Doenças Periodontais/imunologia , Receptores de Superfície Celular/imunologia , Receptores Imunológicos , Regulação para Cima , Antígeno CD83
11.
J Physiol Pharmacol ; 54 Suppl 4: 127-41, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15075455

RESUMO

The pancreatic gland has an enormous potential for growth and regeneration, mainly in rodents. These processes remain mostly under the control of the GI hormone cholecystokinin (CCK). The human pancreas however does not show proliferative properties after partial pancreatectomy, but research in this field has been scarce. Recent studies indicate that CCK might not be the expected trophic agent since its two receptors CCK(A) and CCK(B) were not found on human exocrine pancreas. Therefore, if human pancreas grows and regenerates, it has to be under the influence of some unknown trophic factors. Neuropeptides receiving much attention lately as regulators of pancreatic functions could be among the searched trophic agents. This presentation focus on neuropeptides growth potential: GRP-Bombesin, GABA, PP, PYY, Neurotensin, SP, VIP, PACAP, CGRP and galanin. Some neuropeptides have moderate effects on pancreatic enzymes and electrolytes secretion: SP, VIP, PACAP. However, their trophic effects remain unexplored except for GRP-bombesin and PACAP. PACAP preferentially exhibits its mitogenic and proliferative effects on the pancreatic acinar cells AR4-2J via tyrosine kinase, phospholipase D and ornithine decarboxylase activation but not through adenylate cyclase. The growth promoting action of GRP-bombesin is well documented on rodent's pancreas. However, recent studies indicate that this neuropeptide is potentially trophic for larger mammals' pancreas. Indeed, investigators recently documented that bombesin induced pancreatic regeneration in the pig after partial pancreatectomy through mitogen-activated protein kinases activation as do CCK-8 and caerulein on rat pancreas. Have we found the magic pancreatic trophic factor in large mammals? Further investigations will tell.


Assuntos
Colecistocinina/fisiologia , Trato Gastrointestinal/fisiologia , Neuropeptídeos/fisiologia , Pâncreas/crescimento & desenvolvimento , Regeneração/fisiologia , Animais , Hormônios Gastrointestinais/fisiologia , Humanos , Pâncreas/fisiologia
13.
Biochem Biophys Res Commun ; 285(2): 207-16, 2001 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-11444827

RESUMO

Large increases in cAMP concentration inside the cell are generally growth inhibitory for most cell lines of mesenchymal and epithelial origin. Moreover, recent data suggest a role of cAMP in survival of different cell types. Herein, the ability of forskolin (an adenylyl cyclase activator) and IBMX (3-isobutyl-1-methylxanthine) (a phosphodiesterase inhibitor) to modulate cell cycle progression and survival of human pancreatic cancer cells was evaluated. We showed that forskolin + IBMX inhibited serum-induced ERK activities, Rb hyperphosphorylation, Cdk2 activity, and p27(Kip1) downregulation and caused G1 arrest in MIA PaCa-2 cells. Furthermore, forskolin + IBMX protected pancreatic cells against apoptosis induced by prolonged inhibition of ERK activities by preventing Bcl-X(L) downregulation, activation of caspases 3, 6, 8, and 9, and PARP cleavage and by inducing Bad phosphorylation (ser112). Taken together, our data demonstrate for the first time that cAMP is an inhibitor of cell cycle progression and apoptosis in human pancreatic cancer cells.


Assuntos
1-Metil-3-Isobutilxantina/farmacologia , Apoptose/fisiologia , Quinases relacionadas a CDC2 e CDC28 , Ciclo Celular/fisiologia , Colforsina/farmacologia , AMP Cíclico/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Pancreáticas/patologia , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Adesão Celular/fisiologia , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Meios de Cultura , Quinase 2 Dependente de Ciclina , Quinases Ciclina-Dependentes/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína do Retinoblastoma/metabolismo , Células Tumorais Cultivadas , Proteína bcl-X
14.
Pancreas ; 21(3): 321-4, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11039478

RESUMO

Positive signs of pancreas regeneration were observed in rats after induced pancreatitis and partial pancreatectomy (1,2). Although the human pancreas did not regenerate after partial anatomic resection (3), the pig pancreas exhibited growth responses to bombesin after partial pancreatectomy (4). This study was undertaken to establish the time course of pancreatic inflammation, apoptosis, and hypertrophy and/or hyperplasia after partial pancreatectomy in pigs.


Assuntos
Apoptose , Pâncreas/patologia , Pancreatectomia , Pancreatite , Animais , DNA/análise , Ativação Enzimática , Feminino , Hiperplasia , Cinética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Pâncreas/fisiopatologia , Regeneração , Suínos
15.
J Cell Biochem ; 79(3): 355-69, 2000 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-10972974

RESUMO

BACKGROUND AND AIMS: Growth factors are well known for their participation in the regulation of cell proliferation and survival. However, the intracellular signaling pathways by which growth factors promote survival are still poorly understood. In the present study, using the MIA PaCa-2 cell line, a well-established model of pancreatic cancer cells, we analyzed the roles of ERK1/2 activities in the regulation of cell survival and investigated some of the mechanisms involved. METHODS: The ability of the MEK inhibitor PD98059 to modulate survival of the MIA PaCa-2 cells was evaluated, and the responses were correlated with expression of Bcl-2 homologs and caspases 1, 3, 6, 8, and 9 activities. RESULTS: Herein, we showed that inhibition of ERK1/2 activities caused (1) a G1 arrest; (2) a down-regulation of the expression levels of the anti-apoptotic homologs Bcl-2, Mcl-1, and Bcl-X(L) without affecting the pro-apoptotic levels of Bax and Bak; (3) a promotion of caspases 3, 6, 8, and 9 activities; (4) a stimulation of PARP cleavage; and (5) a programmed cell death by apoptosis. CONCLUSION: Our data suggest that activation of the ERK pathway functions to protect pancreatic tumor cells from apoptosis as well as to regulate their progression in the cell cycle.


Assuntos
Carcinoma/patologia , Ciclo Celular/fisiologia , Flavonoides/farmacologia , MAP Quinase Quinase Quinase 1 , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/fisiologia , Neoplasias Pancreáticas/patologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Apoptose/efeitos dos fármacos , Carcinoma/metabolismo , Caspases/biossíntese , Caspases/genética , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular , Cisteína Endopeptidases/fisiologia , Inibidores de Cisteína Proteinase/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Complexos Multienzimáticos/fisiologia , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Prostaglandina-Endoperóxido Sintases/fisiologia , Complexo de Endopeptidases do Proteassoma , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Piridinas/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína bcl-X
16.
Am J Physiol Gastrointest Liver Physiol ; 279(1): G148-56, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10898757

RESUMO

In rodents, cholecystokinin (CCK) induces pancreatic enzyme secretion and pancreas growth through its CCK(A) receptors. It is unknown whether occupation of the CCK(B) receptors present in pig and human pancreas can cause the same effects. This study evaluates CCK(B) receptor expression in rat, mouse, pig, and fetal human pancreata using Northern blot, Western blot, and immunofluorescence techniques. The reported 2.7-kb CCK(B) receptor mRNA transcript in the rat brain and gastric fundus is absent in pancreas; the message was, however, detected by RT-PCR and by a CCK(B) receptor antibody as an 80-kDa protein present uniquely in islet delta-cells. Proteins of 50 and 80 kDa appear in mouse pancreas, and proteins of 50 and 115 kDa appear in pig and human pancreas, respectively, all localized in islet delta-cells. Gastrin mRNAs are strongly present in fetal rat pancreas, and the hormone is localized in islets; both are repressed 10 days after birth. In conclusion, the CCK(B) receptors are present in pancreas of four species with exclusive location in islet delta-cells. In such a location, they could be indirectly involved in the control of enzyme secretion.


Assuntos
Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Receptores da Colecistocinina/metabolismo , Somatostatina/metabolismo , Animais , Northern Blotting , Western Blotting , Divisão Celular/fisiologia , Colecistocinina/metabolismo , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Gastrinas/metabolismo , Expressão Gênica/fisiologia , Humanos , Ilhotas Pancreáticas/química , Masculino , Camundongos , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptor de Colecistocinina B , Receptores da Colecistocinina/análise , Receptores da Colecistocinina/genética , Suínos
17.
Pancreas ; 20(4): 323-36, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10824686

RESUMO

This study was undertaken to characterize the biochemical properties of rat pancreatic phospholipase D (PLD). Based on Western blot analysis of pancreas subcellular fractions, PLD1 was detected as a protein of 120 kDa associated with the microsomal fraction, whereas PLD2 appeared as a 105-kDa protein enriched in the microvesicular fraction. In these fractions, a low level of PLD activity was measured with an exogenous substrate containing phosphatidylinositol-4,5-bisphosphate (PIP2), unresponsive to guanosine triphosphate (GTP)gammaS and adenosine diphosphate (ADP)-ribosylation factor (ARF). Addition of unsaturated but not saturated fatty acids stimulated an oleate-dependent PLD activity that colocalized with the PLD1 enzyme in the crude plasma membrane and microsomal fractions. The transphosphatidylation reaction was maximal with either 200-400 mM (1.2-2.3%) ethanol or 25 mM (0.23%) 1-butanol, with an optimal pH between 6.5 and 7.2. Lipids extracted from the pancreatic membranes were potent inhibitors of the HL60 cell PLD activity when compared with those isolated from HL60 cells. Oleate-dependent PLD activity was less susceptible to these inhibitions. A phospholipase A1 (PLA1) activity hydrolyzing phosphatidylethanol also was found in the pancreatic membrane fractions and was nearly absent in the HL60 cells. This activity was completely inhibited by 400 nM tetrahydrolipstatin (THL), a lipase inhibitor. Pancreatic PLD1 and PLD2 activities could be measured after a chromatographic separation from microsomal membranes and high-speed supernatants, respectively. Activities of both enzymes were inhibited by oleate and required the presence of PIP2 in the substrate vesicles. ARF1 strongly activated PLD1 in a dose-dependent manner, and PLD2 was slightly responsive. Indirect immunofluorescence revealed that PLD2 is distributed throughout the pancreas, with a more intense staining in the islets. This study presents for the first time biochemical characteristics of the pancreatic PLD activities and shows the presence of oleate-dependent PLD1 and PLD2 activities, as well as PLD1 and PLD2 proteins in this gland.


Assuntos
Isoenzimas/análise , Pâncreas/ultraestrutura , Fosfolipase D/análise , Frações Subcelulares/enzimologia , Animais , Linhagem Celular , Membrana Celular/enzimologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/análise , Inibidores Enzimáticos/farmacologia , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Microssomos/enzimologia , Peso Molecular , Ácido Oleico/farmacologia , Pâncreas/enzimologia , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfolipase D/antagonistas & inibidores , Fosfolipase D/metabolismo , Fosfolipases A/metabolismo , Fosfolipases A1 , Ratos
18.
Am J Physiol ; 277(5): G953-9, 1999 11.
Artigo em Inglês | MEDLINE | ID: mdl-10564100

RESUMO

Pancreatic growth occurs after CCK, CCK-induced pancreatitis, and pancreatectomy; the mechanisms involved remain unknown. This study evaluates mitogen-activated protein kinase (MAPK) activation and expression of cell cycle regulatory proteins after pancreatectomy to understand the cellular and molecular mechanisms involved in pancreas regeneration. Rats were killed 1-12 days after pancreatectomy, and p42/p44 MAPK activation, expression of the cyclins D and E, cyclin-dependent kinase (Cdk)-2 activity, retinoblastoma protein (pRb) hyperphosphorylation, and expression of the cyclin kinase inhibitors p15, p21, and p27 were examined. Pancreatic remnants exhibited sustained p42/p44 MAPK activation within 8 h. Cyclins D1 and E showed maximal expression after 2 and 6 days, coinciding with maximal hyperphosphorylation of pRb and Cdk2 activity. The expression of p15 vanished after 12 h, p27 disappeared gradually, and p21 increased early. The p27 complexed with Cdk2 dissociated after 2 days, whereas p21 associated in a reverse fashion. In conclusion, sustained activation of p42/p44 MAPKs and Cdk2 along with overexpression of cyclins D1 and E and reduction of p15 and p27 cyclin inhibitors occurred early after pancreatectomy and are active factors involved in signaling that leads to pancreas regeneration.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Proteínas de Ciclo Celular , Ciclina D1/biossíntese , Ciclina E/biossíntese , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Pâncreas/enzimologia , Regeneração/fisiologia , Proteínas Supressoras de Tumor , Animais , Ciclo Celular/fisiologia , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Pâncreas/citologia , Pâncreas/cirurgia , Pancreatectomia , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína do Retinoblastoma/metabolismo
19.
Cell Signal ; 11(8): 591-602, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10433520

RESUMO

The implication of MAP kinases in the proliferation control of pancreatic cancer cells is still unknown. This study was undertaken to examine the contribution of the p44/p42 and p38 MAP kinases in the mitogenic response to epidermal growth factor (EGF) and bombesin in human pancreatic cancer cells, MIA PaCa-2 and PANC-1. Data indicate that EGF and bombesin stimulated growth of both cell lines. In MIA PaCa-2 cells, EGF and bombesin stimulated the in gel activation of p38 while p44/p42 kinases exhibited high basal activity and no response to stimuli. Growth and p38 activation were inhibited by genistein, wortmannin, PD98059 and SB203580, specific inhibitors of tyrosine kinase, phosphatidylinositol 3-kinase, MEK-1 and p38 kinases, respectively. In PANC-1 cells, EGF and bombesin stimulated p42 in gel activation; p44 remained highly activated and unresponsive to stimuli and p38 did not respond. Stimulated growth and p42 activation were inhibited by genistein, wortmannin and PD98059. Estimation of MAPK activities with a specific anti-active MAP kinase antibody indicated, however, that EGF increased the intensity of the bands corresponding to p42 and p44 MAP kinases in both cell lines, indicating that the mitogenic factor can regulate MAP kinase activity. Data also pointed out that ATP is sufficient to increase MAP kinase activity within the in gel assay technique and may thus explain the discrepancies existing between the in gel assay data and those obtained with the anti-active MAP kinase antibody.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno , Neoplasias Pancreáticas/enzimologia , Trifosfato de Adenosina/metabolismo , Bombesina/metabolismo , Bombesina/farmacologia , Divisão Celular/efeitos dos fármacos , Ativação Enzimática , Fator de Crescimento Epidérmico/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Humanos , Proteína Quinase 3 Ativada por Mitógeno , Fosforilação , Células Tumorais Cultivadas , Proteínas Quinases p38 Ativadas por Mitógeno
20.
Biochem Biophys Res Commun ; 260(3): 820-8, 1999 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-10403848

RESUMO

We have evaluated the presence and localization of the CCK(A) receptor in rat, mouse, pig and human fetal pancreas by Northern, Western blots and immunofluorescence techniques. In the rat, parallelism exists between development of the CCK(A) receptor mRNA and protein with maximal peaks of expression during the suckling period. In the course of pancreatitis induction, CCK(A) receptor mRNA were maximally expressed and sustained during the gland's regeneration. In the rat and mouse pancreas, the CCK(A) receptor protein is localized around the acinar cells and beta cells of the islets of Langerhans. In the adult pig and fetal human pancreas, the CCK(A) receptor proteins were detected by Western blot. By immunofluorescence, its detection was possible only in the islet of Langerhans of the pig pancreas. These new findings support the views that CCK plays important and various roles in specific physiological systems of the pancreas of different species.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Ilhotas Pancreáticas/metabolismo , Pâncreas/metabolismo , Receptores da Colecistocinina/metabolismo , Animais , Colecistocinina/genética , Feminino , Humanos , Mucosa Intestinal/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/embriologia , Ilhotas Pancreáticas/crescimento & desenvolvimento , Masculino , Camundongos , Pâncreas/citologia , Pâncreas/embriologia , Pâncreas/crescimento & desenvolvimento , Pancreatite/induzido quimicamente , Pancreatite/metabolismo , Pancreatite/patologia , Pancreatite/fisiopatologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor de Colecistocinina A , Receptores da Colecistocinina/agonistas , Receptores da Colecistocinina/análise , Receptores da Colecistocinina/genética , Regeneração , Especificidade da Espécie , Suínos
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