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1.
Clin Res Hepatol Gastroenterol ; 48(5): 102324, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38527568

RESUMO

BACKGROUND AND OBJECTIVE: LPAC (low phospholipid-associated cholelithiasis) syndrome is a rare genetic form of cholelithiasis. ERCP (endoscopic retrograde cholangiopancreatography) is often used to remove gallstones in the bile duct. No published data is available on the role of ERCP in LPAC syndrome. PATIENTS AND METHODS: In this retrospective cohort study, we included patients diagnosed with LPAC syndrome in a single tertiary referral center between 2009 and 2021. Our aim was to assess the frequency, indications, modalities, results, and complications of ERCP, as well as predictive factors for ERCP, in LPAC syndrome. Independent factors associated with ERCP occurrence were identified using a multivariable Cox regression analysis. RESULTS: ERCP was required in 31.2 % of the 269 patients included for analysis. Among patients who required ERCPs, 78.6 % had the procedure before diagnosis (i.e., starting UDCA). Most common indications were choledocholithiasis (53.6 %) and acute cholangitis (29.5 %). Post ERCP pancreatitis, perforation and bleeding rates were 7.2 %, 2.6 %, and 1.3 %, respectively. Age and history of cholelithiasis in first-degree relatives were associated with a higher risk of ERCP (Hazard-ratio [HR]=1.30 [95 %confidence-interval [CI] 1.04-1.62] and HR=1.88 [95 %CI 1.15-3.07] respectively). Female gender and UDCA intake ≥ 1 year were associated with a lower risk of ERCP (HR=0.49 [95 %CI 0.29-0.82] and HR=0.44 [95 %CI 0.22-0.90] respectively). Median follow-up was 10.8 years. CONCLUSION: One-third of patients with LPAC syndrome undergo sphincterotomy. However, most procedures are performed before diagnosis and UDCA is associated with a lower risk of endoscopic procedure. Earlier diagnosis and treatment with UDCA may further reduce the need for ERCP in patients with LPAC syndrome.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Colelitíase , Humanos , Estudos Retrospectivos , Feminino , Masculino , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Pessoa de Meia-Idade , Colelitíase/complicações , Adulto , Estudos de Coortes , Idoso , Síndrome , Colangite/etiologia , Coledocolitíase/complicações
2.
Aliment Pharmacol Ther ; 43(2): 294-302, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26526892

RESUMO

BACKGROUND: Pruritus is a common symptom associated with cholestatic liver diseases. To date only small single centre case series have suggested efficacy of nasobiliary drainage in relieving cholestatic pruritus. AIM: To perform a multicentre study to evaluate the safety and efficacy of nasobiliary drainage in cholestatic pruritus. METHODS: This was a retrospective study of all patients treated with nasobiliary drainage for refractory cholestatic pruritus between 2006 and 2015 at five European centres. Pruritus was quantified using a visual analogue scale (VAS) and liver enzymes, serum bilirubin and total serum bile salts (TBS) were measured before (pre-NBD) and after nasobiliary drainage (post-NBD). We analysed the duration of treatment response and associated complications. RESULTS: In total, 27 patients (59% females) underwent 29 nasobiliary drainage procedures. The median duration of NBD was 7 days. NBD decreased pruritus in 89.6% of cases (VAS from 10.0 to 0.3, P < 0.0001). The median percentage decline in pruritus VAS was 94% and 33% of patients were free of pruritus within 24 h of starting drainage. The duration of treatment response was independent of duration of drainage (P = 0.12) and bile output. Significant improvements were seen in the median levels of serum alkaline phosphatase (P = 0.001) and serum bilirubin (P = 0.03) but not in serum TBS (P = 0.07). Mild post-endoscopic retrograde cholangiopancreatography pancreatitis (31%) was the most frequent complication. CONCLUSIONS: Nasobiliary drainage is effective in relieving cholestatic pruritus in most patients and has favourable effect on biomarkers of cholestasis. Nasobiliary drainage may be associated with high risk of adverse events, especially pancreatitis. Prospective studies are needed to confirm our findings.


Assuntos
Colestase/complicações , Drenagem/métodos , Prurido/terapia , Adulto , Bile/metabolismo , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/etiologia , Prurido/etiologia , Estudos Retrospectivos
3.
Rev Med Interne ; 31(9): 606-14, 2010 Sep.
Artigo em Francês | MEDLINE | ID: mdl-20674103

RESUMO

Autoimmune hepatitis is a disorder of unknown aetiology that occurs in children and adults of all ages with a female predominance. The spectrum of presentation is wide, ranging from no symptoms to acute liver failure. The diagnosis is based on high level serum gammaglobulins, characteristic circulating autoantibodies and histologic abnormalities (necrosis and inflammation). Autoimmune hepatitis is classified on the basis of the autoantibody pattern: type 1 (antinuclear and/or smooth muscle antibodies) is the classic form whereas type II (liver-kidney microsome 1 antibody) is much less common and occurs mainly in childhood. Mixed forms of autoimmune hepatitis that share features with other putative autoimmune liver diseases, primary biliary cirrhosis and primary sclerosing cholangitis, have been described. Because of therapeutic issues, it is important to distinguish autoimmune hepatitis from other forms of hepatitis and the use of diagnostic scoring systems may be helpful. The treatment of autoimmune hepatitis has not changed for the past 30 years. It consists of corticosteroids associated with azathioprine. This treatment is rapidly effective but usually only suspensive. Relapse after treatment withdrawal is the rule (80% of cases). The main risk factor of recurrence is the degree of residual inflammation on liver biopsy. The frequency of side effects justifies an attempt of drug discontinuation provided that criteria of clinical, biochemical and histological remission are achieved after at least 2 years of treatment.


Assuntos
Hepatite Autoimune/diagnóstico , Hepatite Autoimune/tratamento farmacológico , Humanos
4.
Gastroenterol Clin Biol ; 34(4-5): 283-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20417047

RESUMO

BACKGROUND/AIMS: To assess the benefit of the UDCA-budesonide combination in association with mycophenolate mofetil (MMF) in patients with primary biliary cirrhosis (PBC) at high risk of developing cirrhosis or liver failure. METHODS: Inclusion criteria for this three-year open study were: 1) suboptimal biochemical response to one-year UDCA therapy at 13-15 mg/kg/d; 2) significant interface hepatitis without cirrhosis at liver biopsy. Treatment regimen included UDCA (13-15 mg/kg/d), budesonide (6 mg/d) and MMF (1.5 g/d). All patients underwent a control biopsy at three years. RESULTS: Fifteen patients fulfilled the inclusion criteria. Six patients (41%) normalized biochemistries and seven (47%) had a partial but significant biochemical response, as defined by a serum bilirubin less than 17 micromol/L, alanine aminotransferase less than 70 UI/L and alkaline phosphatase less than 250 UI/L. Histological activity and fibrosis were markedly improved. Side effects were minimal or absent. CONCLUSIONS: Triple therapy with UDCA, budesonide and MMF may provide benefit in non-cirrhotic PBC patients with features of severe disease not responding to UDCA.


Assuntos
Budesonida/uso terapêutico , Cirrose Hepática Biliar/tratamento farmacológico , Ácido Micofenólico/análogos & derivados , Ácido Ursodesoxicólico/uso terapêutico , Adulto , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Bilirrubina/sangue , Colagogos e Coleréticos/uso terapêutico , Quimioterapia Combinada , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Cirrose Hepática/prevenção & controle , Falência Hepática/prevenção & controle , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Índice de Gravidade de Doença
5.
Rev Neurol (Paris) ; 165(10): 828-30, 2009 Oct.
Artigo em Francês | MEDLINE | ID: mdl-19217129

RESUMO

INTRODUCTION: Neurological complications of metronidazole are rare, predominantly peripheral neuropathies, especially in patients on a long-term high-dose regimen. Cerebellar syndrome or seizures are less frequently reported. The concomitant occurrence of the three complications is exceptional. CASE REPORT: We report herein a case with these three complications as side effects of metronidazole. For the cerebellar syndrome, the T2-weighted brain MRI showed a rounded and well-delimited zone of high signal intensity in the cerebellar dentate nuclei, extending up to the protuberance and the subthalamic nucleus, bilaterally and symmetrically. CONCLUSION: Neurological complications are possible when a treatment with metronidazole is prescribed for a long duration or at high dose. In our patient, the clinical abnormalities and MRI signs regressed a few months after treatment withdrawal.


Assuntos
Doenças Cerebelares/induzido quimicamente , Metronidazol/efeitos adversos , Neurite (Inflamação)/induzido quimicamente , Convulsões/induzido quimicamente , Idoso , Doenças Cerebelares/patologia , Cerebelo/patologia , Epilepsias Mioclônicas/induzido quimicamente , Epilepsias Mioclônicas/fisiopatologia , Humanos , Transplante de Fígado , Imageamento por Ressonância Magnética , Masculino , Neurite (Inflamação)/patologia , Convulsões/patologia , Núcleo Subtalâmico/patologia , Difração de Raios X
6.
Can J Gastroenterol ; 21(12): 839-42, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18080057

RESUMO

A common characteristic of all chronic liver diseases is the occurrence and progression of fibrosis toward cirrhosis. Consequently, liver fibrosis assessment plays an important role in hepatology. Besides its importance for prognosis, determining the level of fibrosis reveals the natural history of the disease and the risk factors associated with its progression, to guide the antifibrotic action of different treatments. Currently, in clinical practice, there are three available methods for the evaluation of liver fibrosis: liver biopsy, which is still considered to be the 'gold standard'; serological markers of fibrosis and their mathematical combination - suggested in recent years to be an alternative to liver biopsy - and, more recently, transient elastography (TE). TE is a new, simple and noninvasive method used to measure liver stiffness. This technique is based on the progressing speed of an elastic shear wave within the liver. Currently, there are only a few studies that have evaluated TE effectiveness in chronic liver diseases, mostly in patients infected with the hepatitis C virus. Further studies are needed in patients with chronic liver disease, to assess the effectiveness of the fibrosis treatment.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Gastroenterologia/métodos , Hepatopatias/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Reprodutibilidade dos Testes
8.
J Hepatol ; 35(3): 324-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11592592

RESUMO

BACKGROUND/AIMS: To determine whether the apolipoprotein E (apo-E) polymorphism is associated with the risk of primary biliary cirrhosis (PBC), the severity of the disease and its response to ursodeoxycholic acid (UDCA) therapy. METHODS: The apo-E genotype was determined in 72 PBC patients. Genotype and allele distributions were compared with those found in the French general population. Laboratory parameters obtained before and after 1- and 4-year UDCA treatment were compared according to the apo-E allele carrier status. RESULTS: Apo-E allele and genotype distributions were similar between PBC patients and the general population. At the time of diagnosis, the epsilon4 allele carriers were younger (P < 0.05), had higher bilirubin (P < 0.05) and IgG (P < 0.001) levels and a lower prothrombin index (P < 0.01) than epsilon2 (homozygous + heterozygous) or epsilon3 homozygous allele carriers. After 4-year UDCA therapy, the decrease in serum alkaline phosphatase and in alanine and aspartate aminotransferase activities was lower in percentage in the epsilon4 than in other epsilon allele carriers (P < 0.01). CONCLUSIONS: Although apo-E polymorphism does not appear to confer susceptibility to PBC, it probably influences PBC progression and response to UDCA. The epsilon4 allele may identify patients with high risk of severe disease and poor response to treatment.


Assuntos
Apolipoproteínas E/genética , Cirrose Hepática Biliar/genética , Polimorfismo Genético , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biomarcadores , Estudos Transversais , Humanos , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/tratamento farmacológico , Estudos Retrospectivos , Ácido Ursodesoxicólico/uso terapêutico
9.
J Hepatol ; 33(5): 696-700, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11097475

RESUMO

BACKGROUND/AIMS: Recent studies have suggested a role of fetal microchimerism in the pathogenesis of scleroderma. The present study investigated the potential role of fetal microchimerism in primary biliary cirrhosis (PBC), a closely related disease. METHODS: A quantitative nested polymerase chain reaction was used to detect Y-chromosome sequences in the peripheral blood or the liver of PBC women and controls having male children and no transfusion or miscarriage history. RESULTS: Male microchimerism was found in the peripheral blood from 45% (9 of 20) of PBC women and 25% (5 of 20) of healthy controls matched for the number of male children and age of the youngest son (p=0.28), and in the liver-biopsy specimens from 33% (5 of 15) of PBC women and 32% (8 of 25) of controls. The level of chimerism did not differ between patients and controls either in blood or in liver. Microchimerism was not related to the severity of the disease but was more frequent in PBC patients with anticentromere antibodies (p=0.049). CONCLUSIONS: Fetal microchimerism does not seem to play a major role in most cases of PBC. However, the association with anticentromere antibodies suggests a possible role in the subgroup of patients with CREST syndrome or scleroderma.


Assuntos
Quimera , DNA/análise , Cirrose Hepática Biliar/etiologia , Cromossomo Y , Adulto , Idoso , Animais , Síndrome CREST/etiologia , Centrômero/imunologia , Feminino , Doença Enxerto-Hospedeiro/etiologia , Humanos , Fígado/patologia , Cirrose Hepática Biliar/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
10.
Hepatology ; 32(6): 1196-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11093724

RESUMO

Ursodeoxycholic acid (UDCA) is the only approved treatment for primary biliary cirrhosis (PBC). However, the benefit from UDCA therapy on the progression of PBC from its early stage towards extensive fibrosis and cirrhosis has not been clearly shown. The aim of this study was to assess the effect of UDCA therapy on liver fibrosis progression in PBC. A Markov model was used to analyze the progression rates between early and late histologic stages in 103 patients with PBC enrolled in a randomized, double-blind, placebo-controlled trial of UDCA. Early stage was defined by the presence of portal and periportal lesions without extensive fibrosis, whereas late stage was defined by the presence of numerous septa, bridging fibrosis, or cirrhosis. A total of 162 pairs of liver biopsy specimens were studied. The model accurately described the observed data. UDCA therapy was associated with a 5-fold lower progression rate from early stage disease to extensive fibrosis or cirrhosis (7% per year under UDCA vs. 34% per year under placebo, P <.002), but was not associated with a significant difference in regression rates (3% per year under both UDCA and placebo). At 4 years, the probability of UDCA-treated patients to remain in early stage disease is 76% (95% confidence interval: 58%-88%), as compared with 29% (15%-52%) in placebo-treated patients. In conclusion, UDCA therapy significantly delays the progression of liver fibrosis in PBC. Markov modeling should prove useful in assessing the efficacy of future medical treatments in clinical trials involving histologic endpoints.


Assuntos
Cirrose Hepática Biliar/complicações , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Ácido Ursodesoxicólico/uso terapêutico , Progressão da Doença , Método Duplo-Cego , Humanos , Cadeias de Markov , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Am J Pathol ; 155(4): 1065-73, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10514389

RESUMO

We tested the potential role of vascular endothelial growth factor (VEGF) and of fibroblast growth factor-2 (FGF-2) in the angiogenesis associated with experimental liver fibrogenesis induced by common bile duct ligation in Sprague-Dawley rats. In normal rats, VEGF and FGF-2 immunoreactivities were restricted to less than 3% of hepatocytes. One week after bile duct ligation, hypoxia was demonstrated by the immunodetection of pimonidazole adducts unevenly distributed throughout the lobule. After 2 weeks, hypoxia and VEGF expression were detected in >95% of hepatocytes and coexisted with an increase in periportal vascular endothelial cell proliferation, as ascertained by Ki67 immunolabeling. Subsequently, at 3 weeks the density of von Willebrand-labeled vascular section in fibrotic areas significantly increased. Semiquantitative reverse transcription polymerase chain reaction showed that VEGF(120) and VEGF(164) transcripts, that correspond to secreted isoforms, increased within 2 weeks, while VEGF(188) transcripts remained unchanged. FGF-2 mainly consisting of a 22-kd isoform, according to Western blot, was identified by immunohistochemistry in 49% and 100% of hepatocytes at 3 and 7 weeks, respectively. Our data provide evidence that in biliary-type liver fibrogenesis, angiogenesis is stimulated primarily by VEGF in response to hepatocellular hypoxia while FGF-2 likely contributes to the maintenance of angiogenesis at later stages.


Assuntos
Fatores de Crescimento Endotelial/biossíntese , Cirrose Hepática Biliar/metabolismo , Cirrose Hepática Experimental/metabolismo , Linfocinas/biossíntese , Neovascularização Patológica/metabolismo , Animais , Western Blotting , Hipóxia Celular , Fator 2 de Crescimento de Fibroblastos/metabolismo , Imuno-Histoquímica , Antígeno Ki-67/biossíntese , Cirrose Hepática Biliar/patologia , Cirrose Hepática Experimental/patologia , Masculino , Neovascularização Patológica/patologia , Nitroimidazóis/metabolismo , Isoformas de Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
12.
Am J Gastroenterol ; 93(12): 2586-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9860434

RESUMO

We report the case of a 40-yr-old man presenting with symptoms of small bowel obstruction. Small bowel x-rays revealed a stricture of the mid-jejunum. Push enteroscopy found a polypoid mass at 1 meter of the ligament of Treitz. Histopathological examination of the biopsy and surgical specimens showed a diffuse infiltrate of the mucosa made of medium to large cells, which were stained on immunohistochemistry by the leucocyte marker CD45 and the histiocyte/monocyte marker CD68 but were negative for the B and T cell markers. Cytological examination of the ascitic fluid revealed many myelobasts with cytoplasmic Auer rods and positive myeloperoxidase staining. There was no evidence of blood or bone marrow involvement suggestive of acute leukemia or myeloproliferative disorders. These findings were consistent with the diagnosis of preleukemic granulocytic sarcoma (or chloroma). Chemotherapy led to complete remission, but 21 months later the patient developed an acute myeloid leukemia. He died from aspergillus pneumonitis, 10 months after bone marrow allograft. Preleukemic granulocytic sarcoma of the small bowel is a rare condition and its diagnosis is usually not easy, requiring histochemical or immunohistochemical studies. Most cases have progressed to acute myeloid leukemia.


Assuntos
Neoplasias Intestinais/complicações , Obstrução Intestinal/etiologia , Intestino Delgado , Jejuno , Leucemia Mieloide/complicações , Adulto , Endoscopia , Humanos , Neoplasias Intestinais/patologia , Obstrução Intestinal/diagnóstico por imagem , Intestino Delgado/diagnóstico por imagem , Jejuno/patologia , Leucemia Mieloide/patologia , Masculino , Radiografia
13.
Lancet ; 350(9090): 1511-5, 1997 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-9388399

RESUMO

BACKGROUND: CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy) is commonly overlooked or misdiagnosed owing to its recent identification and its variable mode of presentation. The defective gene in CADASIL is Notch3, which encodes a large transmembrane receptor. To set up a diagnostic test and to delineate the Notch3 domains involved in CADASIL., we undertook mutations analysis in this gene in a group of CADASIL patients. METHODS: 50 unrelated patients with CADASIL and 100 healthy controls were screened for mutations along the entire Notch3 sequence, by means of single-strand conformation polymorphism, heteroduplex, and sequence analysis. FINDINGS: Strongly stereotyped mis-sense mutations, located within the epidermal-growth-factor-like (EGF-like) repeats, in the extracellular domain of Notch3, were detected in 45 patients. Clustering of mutations within the two exons encoding the first five EGF-like repeats was observed (32 patients). All these mutations lead to loss or gain of a cysteine residue and therefore to an unpaired number of cysteine residues within a given EGF domain. None of these mutations was found in the 100 controls. INTERPRETATION: Because of the strong clustering and highly stereotyped nature of the pathogenetic mutations detected in CADASIL patients, and easy and reliable diagnostic test for CADASIL is feasible. The findings suggest that aberrant dimerisation of Notch3, due to abnormal disulphide bridging with another Notch3 molecule or with another protein, may be involved in the pathogenesis of this disorder.


Assuntos
Doenças Arteriais Cerebrais/genética , Infarto Cerebral/genética , Leucoencefalopatia Multifocal Progressiva/genética , Mutação , Proteínas Proto-Oncogênicas/genética , Receptores de Superfície Celular , Estudos de Casos e Controles , Doenças Arteriais Cerebrais/diagnóstico , Infarto Cerebral/diagnóstico , Análise Mutacional de DNA/métodos , Fator de Crescimento Epidérmico/genética , Testes Genéticos , Genótipo , Humanos , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Receptor Notch3 , Receptores Notch
14.
Ann N Y Acad Sci ; 826: 213-7, 1997 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-9329692

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited condition whose key features include recurrent subcortical ischemic events, migraine attacks and vascular dementia in association with diffuse white-matter abnormalities seen on neuroimaging. Pathologic examination shows multiple small deep cerebral infarcts, a leukoencephalopathy and a nonatherosclerotic nonamyloid angiopathy involving mainly the media of small cerebral arteries. To progress in understanding the pathophysiological mechanisms of this condition, we undertook the identification of the mutated gene. We mapped the CADASIL gene on chromosome 19p13.1. More than 120 families have been referred to our lab. Genetic linkage analysis of 33 of these families allowed us to reduce the size of the genetic interval to less than 1 cM and to demonstrate the genetic homogeneity of this condition. In the absence of any candidate gene, we undertook positional cloning of this gene. We identified, within the CADASIL critical region, the human Notch3 gene, whose sequence analysis revealed deleterious mutations in CADASIL families co-segregating with the affected phenotype. These data establish that this gene causes CADASIL. Identification of the CADASIL gene will provide a valuable diagnostic tool for clinicians and could be used to estimate the prevalence of this underdiagnosed condition. It should help in the understanding of pathophysiological mechanisms of CADASIL and vascular dementia.


Assuntos
Doenças Arteriais Cerebrais/genética , Infarto Cerebral/genética , Demência Vascular/etiologia , Leucoencefalopatia Multifocal Progressiva/genética , Mutação , Proteínas Proto-Oncogênicas/genética , Receptores de Superfície Celular/genética , Adulto , Doenças Arteriais Cerebrais/complicações , Infarto Cerebral/complicações , Cromossomos Humanos Par 19 , Genes Dominantes , Ligação Genética , Humanos , Leucoencefalopatia Multifocal Progressiva/complicações , Receptor Notch3 , Receptores Notch
15.
Brain Res ; 766(1-2): 276-80, 1997 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-9359616

RESUMO

Concentrations of the neuroactive steroid 3alpha,5alpha-tetrahydroprogesterone (TH PROG or allopregnanolone) and its precursors progesterone (PROG) and 5alpha-dihydroprogesterone (DH PROG) have been measured in mouse brain throughout the oestrous cycle. Plasma PROG concentrations were also measured for comparison. At each stage, circadian fluctuations were found in the concentrations of brain PROG and its metabolites. Such fluctuations were greater than those attributable to any particular stage of the oestrous cycle. Over the entire cycle, a significant correlation was found between brain TH PROG (or DH PROG) and PROG concentrations but not between brain TH PROG (or DH PROG) and plasma PROG concentrations. There was also no correlation between endogenous TH PROG (or DH PROG) and activity of the 5alpha-reductase converting 3H-PROG to 3H-DH PROG in whole brain homogenates. Concentrations of another neuroactive steroid, pregnenolone sulphate (PREG S), in the brain during the oestrous cycle were in phase with plasma PROG but not brain PROG concentrations. Our results indicate that circadian and ovarian influences on the concentrations of PROG and its metabolite TH PROG in female whole mouse brain are caused predominantly by changes in the supply of PROG from within the tissue, whatever the contribution of peripheral sources.


Assuntos
Estro/metabolismo , Moduladores GABAérgicos/metabolismo , Pregnanodionas/metabolismo , Pregnanolona/metabolismo , Progesterona/metabolismo , 3-Hidroxiesteroide Desidrogenases/metabolismo , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica) , 5-alfa-Di-Hidroprogesterona , Animais , Encéfalo/enzimologia , Química Encefálica/fisiologia , Ritmo Circadiano/fisiologia , Feminino , Camundongos
16.
Proc Natl Acad Sci U S A ; 94(26): 14865-70, 1997 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-9405705

RESUMO

Pregnenolone sulfate (PREG S) is synthesized in the nervous system and is a major neurosteroid in the rat brain. Its concentrations were measured in the hippocampus and other brain areas of single adult and aged (22-24 month-old) male Sprague-Dawley rats. Significantly lower levels were found in aged rats, although the values were widely scattered and reached, in about half the animals, the same range as those of young ones. The spatial memory performances of aged rats were investigated in two different spatial memory tasks, the Morris water maze and Y-maze. Performances in both tests were significantly correlated and, accompanied by appropriate controls, likely evaluated genuine memory function. Importantly, individual hippocampal PREG S and distance to reach the platform in the water maze were linked by a significant correlation, i.e., those rats with lower memory deficit had the highest PREG S levels, whereas no relationship was found with the PREG S content in other brain areas (amygdala, prefrontal cortex, parietal cortex, striatum). Moreover, the memory deficit of cognitively impaired aged rats was transiently corrected after either intraperitoneal or bilateral intrahippocampal injection of PREG S. PREG S is both a gamma-aminobutyric acid antagonist and a positive allosteric modulator at the N-methyl-D-aspartate receptor, and may reinforce neurotransmitter system(s) that decline with age. Indeed, intracerebroventricular injection of PREG S was shown to stimulate acetylcholine release in the adult rat hippocampus. In conclusion, it is proposed that the hippocampal content of PREG S plays a physiological role in preserving and/or enhancing cognitive abilities in old animals, possibly via an interaction with central cholinergic systems. Thus, neurosteroids should be further studied in the context of prevention and/or treatment of age-related memory disorders.


Assuntos
Envelhecimento/fisiologia , Cognição/fisiologia , Hipocampo/fisiologia , Pregnenolona/fisiologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley
17.
Nature ; 383(6602): 707-10, 1996 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-8878478

RESUMO

Stroke is the third leading cause of death, and vascular dementia the second cause of dementia after Alzheimer's disease. CADASIL (for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) causes a type of stroke and dementia whose key features include recurrent subcortical ischaemic events and vascular dementia and which is associated with diffuse white-matter abnormalities on neuroimaging. Pathological examination reveals multiple small, deep cerebral infarcts, a leukoencephalopathy, and a non-atherosclerotic, non-amyloid angiopathy involving mainly the small cerebral arteries. Severe alterations of vascular smooth-muscle cells are evident on ultrastructural analysis. We have previously mapped the mutant gene to chromosome 19. Here we report the characterization of the human Notch3 gene which we mapped to the CADASIL critical region. We have identified mutations in CADASIL patients that cause serious disruption of this gene, indicating that Notch3 could be the defective protein in CADASIL patients.


Assuntos
Transtornos Cerebrovasculares/genética , Demência/genética , Mutação , Proteínas Proto-Oncogênicas/genética , Receptores de Superfície Celular , Adulto , Idade de Início , Sequência de Aminoácidos , Animais , Infarto Cerebral/genética , Mapeamento Cromossômico , Cromossomos Artificiais de Levedura , Cromossomos Humanos Par 19 , Análise Mutacional de DNA , Drosophila/genética , Humanos , Camundongos , Dados de Sequência Molecular , Receptor Notch3 , Receptor Notch4 , Receptores Notch , Homologia de Sequência de Aminoácidos
19.
Steroids ; 61(3): 144-9, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8852832

RESUMO

Inhibition of the aggressive behavior of castrated male mice toward lactating female intruders by dehydroepiandrosterone (DHEA) is correlated with a decrease of pregnenolone sulfate (PREG S) concentrations in brain. We attempted to establish a cause to effect relationship by preventing the decrease of PREG S with trilostane (TRIL), a competitive inhibitor of delta 5-3 beta-hydroxysteroid dehydrogenase delta 5 --> 4 isomerase enzyme. Indeed, TRIL elicited a large increase of PREG levels in brain. Those of PREG S were, however, unchanged, and TRIL unexpectedly decreased the aggressive behavior of control castrated males and did not counteract the inhibition elicited by DHEA. The neurosedative progesterone (PROG) metabolite, 3 alpha-hydroxy-5 alpha-pregnan-20-one (TH PROG), undetectable in the brain of control mice, reached nanomolar concentration range in TRIL-treated ones. However, injection of appropriate amounts of PROG, producing an even larger increase of brain TH PROG, had no antiaggressive effect. Finally, the latter was attributed to the large (up to 80 nM) TRIL-induced increase of brain 3 alpha,21-dihydroxy-5 alpha-pregnan-20-one, which like TH PROG potentiates inhibitory gamma-aminobutyric acid (GABA)ergic neurotransmission.


Assuntos
3-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Encéfalo/metabolismo , Di-Hidrotestosterona/análogos & derivados , Inibidores Enzimáticos/farmacologia , Pregnanolona/metabolismo , Pregnenolona/metabolismo , Animais , Encéfalo/enzimologia , Desidroepiandrosterona/farmacologia , Di-Hidrotestosterona/farmacologia , Feminino , Humanos , Camundongos , Progesterona/metabolismo , Progesterona/farmacologia , Comportamento Sexual Animal
20.
J Steroid Biochem Mol Biol ; 53(1-6): 355-60, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7626480

RESUMO

Pregnenolone (PREG), synthesized de novo in rodent brain, is the precursor of PREG sulfate (S) and progesterone (PROG). PROG is further converted to 5 alpha-pregnane 3, 20-dione (DH PROG) and to 3 alpha-hydroxy-5 alpha-pregnan-20-one (TH PROG). PROG, DH PROG and TH PROG have been measured in the brain of male and female rats. Neither PROG nor DH PROG disappeared from brain, contrary to plasma, after combined adrenalectomy (ADX) and gonadectomy (CX). Trilostane decreased PROG and increased PREG in the brain of CX+ADX rats and mice, in accordance with a precursor to product relationship. As previously described in CX male mice, the neurosteroid DHEA and its analog 3 beta-methyl-androst-5-en-17-one (CH3-DHEA) inhibited the aggressive behavior of female mice towards lactating female intruders. The decrease of biting attacks by DHEA was definitely more prominent in females neonatally imprinted with testosterone. The degree of inhibition of aggressive behavior was related to the decrease of PREG S concentrations in brain. The memory-enhancing effects of DHEA S and PREG S in male mice have been previously documented. Infusion of PREG S (12 fmol) into the nucleus basalis magnocellularis (NBM) of the rat after the acquisition trial enhanced memory performance in a two-trial recognition task (TTRT). Conversely, TH PROG (6 fmol), which potentiates GABAergic neurotransmission, disrupted performance when injected before the acquisition trial. Accordingly, we have found a positive correlation between the performances of 2-year-old rats in the TTRT and the concentrations of PREG S in the hippocampus, namely animals which performed best had the highest steroid levels.


Assuntos
Comportamento Animal/fisiologia , Pregnenolona/metabolismo , Progesterona/metabolismo , Adrenalectomia , Agressão/efeitos dos fármacos , Envelhecimento , Animais , Desidroepiandrosterona/farmacologia , Di-Hidrotestosterona/análogos & derivados , Di-Hidrotestosterona/farmacologia , Feminino , Humanos , Recém-Nascido , Lactação , Masculino , Memória/fisiologia , Camundongos , Orquiectomia , Radioimunoensaio , Ratos , Ratos Sprague-Dawley , Ácido gama-Aminobutírico/farmacologia
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