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1.
Clin Ter ; 175(2): 92-94, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38571464

RESUMO

Background: Many patients affected by FM present different comorbidities, but to date no case of FM in patients with CRMO has been reported in literature. Several studies show the importance of psychosomatic assessment in FM, but only one reported the presence of allostatic overload. Case presentation: In April 2022, a 21-year-old female patient, a third-year medical student, came to our clinic to be assessed and treated for FM. She presents with a diagnosis of CRMO made in 2014 and a diagnosis of FM made in 2019. Results: At the psychiatric evaluation she presented symptoms of anxiety, depression, insomnia and reported widespread pain with the presence of almost daily headaches. From the psychosomatic point of view using DCPR-revised she presented diagnostic criteria for allostatic overload, related to study and periodic flare-ups of painful symptoms due to CRMO, persistent somatization, with musculoskeletal and gastroenterological symptoms, demoralization and type A behaviour. Conclusion: This case shows how useful a psychosomatic assessment of the patient can be for offering insights into what stressors at the origin of allostatic overload may be present in different FM patients.


Assuntos
Fibromialgia , Osteomielite , Técnicas Projetivas , Feminino , Humanos , Adulto Jovem , Adulto , Fibromialgia/complicações , Fibromialgia/psicologia , Transtornos Psicofisiológicos/complicações , Transtornos Psicofisiológicos/diagnóstico , Transtornos Psicofisiológicos/psicologia , Dor
2.
Aliment Pharmacol Ther ; 44(6): 620-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27443972

RESUMO

BACKGROUND: Therapy of chronic hepatitis D with Interferon is successful when testing for HDV-RNA turns negative. This end-point is disputed. AIM: To assess the role of serum hepatitis B surface antigen (HBsAg) in the clearance of HDV-RNA in pegylated interferon (Peg-IFN)-treated chronic hepatitis D (CHD). METHODS: Sixty-two patients with CHD, treated with Peg-IFN, were considered. The patients belonged to three groups: 14 patients cleared the HBsAg and HDV-RNA (responders, R), 12 cleared the HDV-RNA remaining positive for HBsAg (partial responders, PR) and 36 cleared neither the HBsAg nor the HDV-RNA (nonresponders, NR). RESULTS: In responders, at baseline the median value (mv) of HBsAg and HDV-RNA was 1187 and 188 663 IU/mL. By month 6 of therapy, HBsAg declined to less than 1000 IU/mL and HDV-RNA was undetectable in 12 patients. In NR, the pre-therapy median value of HBsAg and HDV viremia was 6577 and 676 319 IU/mL. There was no significant reduction of antigen at month 6; after a decline, HDV-RNA rebounded to baseline levels. In PR, the median value of baseline HBsAg was 7031 IU/mL; it declined at month 6 in the majority. HDV-RNA progressively declined from an initial median value of 171 405 IU/mL. HBsAg <1000 IU/mL at month 6 discriminated responders and PR from NR (P < 0.001). By ROC curve, the threshold of 0.105 log reduction of HBsAg associated with 1.610 log reduction of HDV-RNA from baseline to month 6 predicted the clearance of this marker. CONCLUSIONS: A reduction of serum HBsAg is mandatory for the definitive clearance of the HDV-RNA. Quantitative HBsAg may predict the long-term response to Peg-IFN therapy and provide a guide to prolong or stop treatment.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite D Crônica/sangue , Hepatite D Crônica/tratamento farmacológico , Interferons/uso terapêutico , Adulto , Feminino , Hepatite D Crônica/diagnóstico , Hepatite D Crônica/virologia , Vírus Delta da Hepatite/genética , Vírus Delta da Hepatite/imunologia , Humanos , Imunoterapia , Cinética , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Viral/análise , RNA Viral/sangue , Resultado do Tratamento , Viremia/diagnóstico , Viremia/tratamento farmacológico
4.
J Viral Hepat ; 13(6): 355-62, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16842437

RESUMO

In this study, we compare results obtained by sequences analysis and commercial kits in the detection of hepatitis B virus (HBV) polymerase and precore (PC) and core promoter mutations. A total of 23 serum samples from lamivudine treated patients were tested for polymerase mutations by direct sequencing, INNO-LiPA HBV DR and AFFIGENE HBV DE/3TC. Full concordance among the three assays was observed in 63% of the total analysed codons. Concordant results were obtained between sequencing and LiPA in 80%, between sequencing and AFFIGENE in 73% and between LiPA and AFFIGENE in 74% of all tested codons. All discrepancies were observed in mixed population samples in which AFFIGENE and LiPA detected additional viral variants not revealed by sequence. In two patients, with serial samples, LiPA detected earlier than sequence and AFFIGENE an emerging mutate strain. PC and core promoter viral variants were detected in 28 serum samples collected from 14 HBV inactive carriers and from 14 hepatitis B patients with chronic liver disease. Direct sequencing, INNO-LiPA HBV PreCore and AFFIGENE HBV MUTANT VL 19 showed fully coincident results in 88% of tested positions. These findings showed that all assays evaluated were sensitive and accurate tools to analyse HBV genomic variability. Sequence analysis is essential to study new emerging mutations as LiPA and AFFIGENE assays are more easily useful in clinical laboratories to detect the appearance of well-characterized HBV variants.


Assuntos
Análise de Sequência de DNA/métodos , Sondas de DNA , DNA Viral/análise , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/enzimologia , Vírus da Hepatite B/genética , Humanos , Lamivudina/uso terapêutico , Mutação , Regiões Promotoras Genéticas , Precursores de Proteínas/genética , DNA Polimerase Dirigida por RNA/genética , Kit de Reagentes para Diagnóstico , Inibidores da Transcriptase Reversa/uso terapêutico
5.
Aliment Pharmacol Ther ; 22(3): 227-32, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16091060

RESUMO

BACKGROUND: Delta virus (HDV)-related chronic hepatitis is difficult to treat. AIMS: To evaluate the efficacy of lamivudine 100 mg daily on serum HDV-RNA, hepatitis D virus antibodies and alanine aminotransferase levels, liver histology, and on hepatitis B surface antigen seroconversion. METHODS: Thirty-one hepatitis B surface antigen-positive, HDV-RNA-positive patients with ALT > or = 1.5 upper normal level and compensated liver disease were randomized (1:2 ratio) to placebo (group A, n = 11) or lamivudine (group B, n = 20) for 52 weeks; thereafter, all patients were given lamivudine for 52 weeks and followed up for 16 weeks. RESULTS: Twenty-five patients (81%) completed the study. No patient was HDV-RNA-negative at week 52; three patients (11%) were negative at week 104. Two of them remained HDV-RNA-negative at week 120, and one lost the hepatitis B surface antigen without seroconversion. Paired pre-treatment and week 104 liver biopsies were available from 19 patients: of which three of seven (43%) from group A and two of 12 patients (17%) from group B had a > or =2 point decrease in the Ishak necroinflammatory score. CONCLUSION: A sustained complete response was achieved in 8% of hepatitis D virus-infected patients treated with lamivudine and a partial histological response in 26% of them. Hepatitis D virus viraemia was unaffected, even in patients when hepatitis B virus replication was lowered by lamivudine therapy.


Assuntos
Antivirais/uso terapêutico , Hepatite D Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Anticorpos Antivirais/sangue , Método Duplo-Cego , Feminino , Antígenos de Superfície da Hepatite B/sangue , Hepatite D Crônica/patologia , Hepatite D Crônica/virologia , Vírus Delta da Hepatite/imunologia , Vírus Delta da Hepatite/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue
6.
Aliment Pharmacol Ther ; 20(3): 281-7, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15274664

RESUMO

AIM: To evaluate the clinical and virological impact of the prolonged use of lamivudine in 94 patients with HBe antigen-negative chronic hepatitis B. METHODS: Initial virological and biochemical responses were obtained in 84 (89%) and in 83 (88%) patients respectively. RESULTS: The virological response peaked within the first 12 months, but diminished to 39% at 48 months because of drug resistance. Overall a virological breakthrough developed in 44 patients (52.4%). After virological breakthrough, the actuarial probability of maintaining biochemical remission diminished to 15% at 24 months and 0% at 29 months. There was no response in 10.6%. Polymerase gene mutations were observed in 82.5% of virological breakthroughs but also in 75% of the non-responders. Overall 7.4% of patients developed a hepatocellular carcinoma. CONCLUSION: Almost 90% of patients responded initially to lamivudine but the emergence of drug resistance progressively reduced the rate of virological remission to 39% at the fourth year of therapy. YMDD mutants explained the 75% of lamivudine resistances and were also selected very early in non-responders. Although the biochemical response is invariably lost within 29 months of the YMDD mutant's duration, the clinical outcome was benign despite severe postvirological breakthrough hepatitic flares in about 12% of cases.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Carcinoma Hepatocelular/etiologia , Avaliação de Medicamentos , Feminino , Seguimentos , Antígenos E da Hepatite B/análise , Hepatite B Crônica/imunologia , Humanos , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
7.
Curr Drug Targets Infect Disord ; 3(1): 25-32, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12570730

RESUMO

Combination therapy (Interferon plus ribavirin) is the current therapeutic gold standard for naive Hepatitis C Virus (HCV)-positive patients and with the recent advent of pegylated (PEG) IFN the rate of the sustained virological response (HCV-RNA clearance 6 months after the end of treatment) is about 54%-56% with a therapeutical gain mainly among patients with unfavourable HCV genotype (1a, 1b); in this subset of patients, a 42%-46% sustained response rate is achieved compared with 33%-36% found among genotype 1 patients treated with the standard therapy. Patients who respond to IFN monotherapy but relapse during the follow-up should be re-treated with combination therapy given for at least 6 months at the minimum dose of 3 MU thrice weekly plus ribavirin 1000 mg/daily. Recent data suggest that prolonging the time of treatment (12 months) may induce a significantly higher rate of sustained response among patients with genotype 1. The efficacy of the combination of IFN and ribavirin in retreating patients with chronic hepatitis C not responding to IFN monotherapy is controversial as it ranges between 0% and 40%. Recent data show an overall rate of sustained response of 23% when an aggressive approach is adopted but increasing the dosage and the time of treatment induces a significant therapeutic benefit only in patients with genotype 1. In conclusion, a therapeutic progress for chronic hepatitis C has been achieved during the last 10 years (56% vs 20% of sustained response rate obtained with IFN monotherapy) but several unresolved issues are yet to be addressed.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Fatores Etários , Alanina Transaminase/sangue , Animais , Transtornos Herdados da Coagulação Sanguínea/complicações , Transtorno Depressivo/complicações , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Genótipo , Hepatite C Crônica/sangue , Hepatite C Crônica/complicações , Humanos , Interferon-alfa/efeitos adversos , Gravidez , Recidiva , Insuficiência Renal/complicações , Resultado do Tratamento
8.
Hepatology ; 34(1): 133-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11431744

RESUMO

To determine whether a higher dosage of interferon (IFN) associated with ribavirin and/or prolonged time of administration may improve therapeutic efficacy, we conducted a 4-arm randomized trial on patients with chronic hepatitis C not responding to one or more previous treatment courses with IFN monotherapy. Group 1 (n = 139) received 3 million units (MU) IFN-alpha2b 3 times a week (t.i.w.) plus ribavirin 1,000 mg/d for 12 months; group 2 (n = 162) received 5 MU t.i.w. plus ribavirin for 12 months; group 3 (n = 142) received 3 MU t.i.w. plus ribavirin for 6 months; and group 4 (n = 151) received 5 MU t.i.w. plus ribavirin for 6 months. The primary end point was hepatitis C virus (HCV)-RNA clearance at the end of 6-month follow-up. HCV-RNA was negative in 15% of group 1, 23% of group 2, 11% of group 3, 16% of group 4 (group 2 vs. group 3, P =.04). Among patients with genotypes 1 and 4, sustained response was significantly higher in group 2 vs. group 3 (18% vs. 7%, P =.03; group 1 = 9%, group 4 = 12%, P = not significant [NS]). In patients with genotypes 2 and 3, sustained virologic response was not affected by the different regimens (group 1 = 32%, group 2 = 30%, group 3 = 30%, group 4 = 35%, P = NS). In conclusion, about 23% of nonresponders to IFN monotherapy may achieve a sustained response if re-treated by 5 MU t.i.w. IFN plus ribavirin 1,000 mg/d for 1 year. Patients with genotype 1 should receive a high dosage of IFN plus ribavirin for 12 months, whereas therapy for patients with genotype 2 or 3 should be less aggressive.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Alanina Transaminase/sangue , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Proteínas Recombinantes , Ribavirina/administração & dosagem , Ribavirina/efeitos adversos , Resultado do Tratamento , Viremia
9.
Pharm Res ; 15(3): 434-41, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9563074

RESUMO

PURPOSE: Alkoxycarbonylamidine prodrug modification was used to mask the positively-charged amidine moiety of an Arg-Gly-Asp peptidomimetic and enhance oral bioavailability. The aqueous stability of ethoxycarbonylamidine (ECA), ethanethiocarbonylamidine (ETCA) and phenoxycarbonylamidine (PCA) prodrugs was examined. METHODS: Degradation was followed by RP-HPLC and rate constants were determined from a degradation scheme defined by product analysis. RESULTS: ECA gave a pH of maximum stability at pH approximately 7 and was independent of pH below pH approximately 4. A novel degradation pathway of ECA, conversion to ethoxycarbonyl- aminocarbonyl, was observed below pH 7. The relative rates below pH 7 were ECA approximately ETCA < PCA, in the same order of decreasing pKa of the conjugate acid of the substituted amidino group. Base-catalyzed cleavage of ECA to yield the amidine derivative gave the relative rates ECA < ETCA < PCA, in agreement with the decreasing pKa of the leaving groups. CONCLUSIONS: The observed rate constants at all pHs were small enough that only 5-30% (depending on the substituent) undesirable degradation is predicted during transit time of the gut. The spontaneous post-absorptive conversion to the amidine drugs at neutral pH is predicted to be 6x greater for the PCA than the ECA prodrugs.


Assuntos
Amidinas/química , Benzodiazepinas/química , Inibidores da Agregação Plaquetária/química , Pró-Fármacos/química , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Solubilidade , Relação Estrutura-Atividade
10.
Bioorg Med Chem ; 6(12): 2345-81, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9925295

RESUMO

Antagonists of the glycoprotein GPIIb/IIIa are a promising class of antithrombotic agents offering potential advantages over present antiplatelet agents (i.e., aspirin and ticlopidine). Novel tricyclic nonpeptidal GPIIb/IIIa antagonists have been prepared and evaluated in vitro as antagonists of fibrinogen binding to the purified GPIIb/IIIa receptor and as inhibitors of platelet aggregation. The work presented demonstrates the robustness of the benzodiazepinedione (BZDD) scaffold, which can be functionalized at the N1-C2 amide as well as at C7, to provide structural diversity and allow optimization of the physiochemical and pharmacological properties of the BZDD based GPIIb/IIIa antagonists. In addition, the resulting new class of tricyclic GPIIb/IIIa antagonists could be used to probe for additional binding interactions on the GPIIb/IIIa receptor and perhaps lead to BZDD based GPIIb/IIIa antagonists with increased potency. The tricyclic molecules reported herein demonstrate that a heterocyclic ring can be fused to the benzodiazepinedione scaffold with retention of anti-aggregatory potency and in the case of tetrazole 30i, increased potency relative to the bicyclic analogue 1c.


Assuntos
Benzodiazepinas/síntese química , Benzodiazepinonas/síntese química , Fibrinolíticos/síntese química , Inibidores da Agregação Plaquetária/síntese química , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Benzodiazepinas/química , Benzodiazepinas/farmacologia , Benzodiazepinonas/química , Benzodiazepinonas/farmacologia , Fibrinolíticos/química , Fibrinolíticos/farmacologia , Humanos , Indicadores e Reagentes , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Relação Estrutura-Atividade
11.
J Med Chem ; 40(5): 717-29, 1997 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-9057858

RESUMO

The benzodiazepinedione class of non-peptidal GPIIbIIIa antagonists has been modified to allow the isolation of noninterconverting rotational isomers, or atropisomers, with the aim of examining their structure-activity relationships as compared to active RGD-containing peptides and other non-peptidal antagonists. Resolution of these antagonists was accomplished by the introduction of a tert-butyl group at N1 and a chlorine at C9 on the 3,4-dihydro-1H-1,4-benzodiazepine-2,5-dione nucleus and enantiospecific substitution on the beta-alanine side chain attached to N4. The relative configuration was determined by single-crystal X-ray analysis. Further, conformational analyses using ab initio calculations were performed to assess the conformational preferences about the beta-alanine side chain. The data support a good topographical correlation between the benzodiazepinedione class of antagonists and the "cupped" presentation of the RGD tripeptide sequence found in the cyclic peptide G4120. The relationship between these compounds with other peptidal and non-peptidal antagonists is discussed.


Assuntos
Benzodiazepinonas/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Benzodiazepinonas/síntese química , Benzodiazepinonas/química , Cristalografia por Raios X , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/química , Estereoisomerismo , Relação Estrutura-Atividade
12.
Cell Biochem Funct ; 13(4): 231-8, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10232925

RESUMO

A structure-activity relationship has been established between calvatic acid and some related synthetic compounds, and their ability to inhibit GTP-induced microtubular protein polymerization in vitro. These compounds were effective in a dose- and a time-dependent manner. The most active drug was the p-chloro substituted compound, which showed its inhibitory activity without any preincubation period, which the others needed. Since if cysteine was present, polymerization was no longer affected, an involvement of titratable -SH groups of tubulin could be suggested. In contrast, taxol-induced polymerization was only slightly inhibited by these compounds, and colchicine-binding activity was not generally impaired.


Assuntos
Antibacterianos/farmacologia , Compostos Azo/farmacologia , Proteínas dos Microtúbulos/química , Animais , Benzoatos/farmacologia , Bovinos , Relação Dose-Resposta a Droga , Técnicas In Vitro , Nitrilas/farmacologia , Polímeros , Relação Estrutura-Atividade
13.
Eur J Drug Metab Pharmacokinet ; 20(4): 249-54, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8983928

RESUMO

In this study we examined the interactions of liver microsomes with the antibiotic calvatic acid and with structural analogues, some of which had shown antimicrotubular properties. These drugs decreased cytochrome P-450 content differently according to the substitutions on the azoxy function and the ethoxycarbonyl derivatives were found to be the most effective ones. The decrease in cytochrome P-450 could be prevented by addition of cysteine or GSH, suggesting an involvement of sulphydryl groups. Furthermore, chromatographic analyses showed that ethoxycarbonyl derivatives were completely metabolized, and this would explain the different behaviour of these compounds towards microtubular protein when they were incubated with purified bovine brain protein or with liver or hepatoma extracts.


Assuntos
Antibacterianos/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Nitrilas/farmacologia , Animais , Antibacterianos/farmacocinética , Benzoatos/farmacocinética , Benzoatos/farmacologia , Biotransformação , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Relação Dose-Resposta a Droga , Masculino , Microssomos Hepáticos/metabolismo , Nitrilas/farmacocinética , Ratos , Ratos Wistar
14.
Cytotechnology ; 11 Suppl 1: S62-4, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7765307

RESUMO

The antiproliferative action of 4-hydroxynonenal (HNE) could be related to an interaction with cytoskeletal structures. In this paper the effects exerted by HNE on microtubules and on microfilaments are examined by immunofluorescence. HNE alters cell morphology causing both the depolymerization of the microtubular structures and the dissolution of the stress-fibres. Taxol protects microtubules, preventing the depolymerizing effect of the aldehyde. The action of HNE could be attributed to its affinity for sulphydryl groups, which are essential in maintaining tubulin and actin both in the polymerized form.


Assuntos
Aldeídos/farmacologia , Citoesqueleto/efeitos dos fármacos , Células 3T3/efeitos dos fármacos , Citoesqueleto de Actina/efeitos dos fármacos , Actinas/metabolismo , Aldeídos/antagonistas & inibidores , Animais , Biotecnologia , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Imunofluorescência , Camundongos , Microtúbulos/efeitos dos fármacos , Paclitaxel/farmacologia , Tubulina (Proteína)/metabolismo
15.
Cytotechnology ; 11(Suppl 1): S62-4, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22358713

RESUMO

The antiproliferative action of 4-hydroxynonenal (HNE) could be related to an interaction with cytoskeletal structures. In this paper the effects exerted by HNE on microtubules and on microfilaments are examined by immunofluorescence. HNE alters cell morphology causing both the depolymerization of the microtubular structures and the dissolution of the stress-fibres. Taxol protects microtubules, preventing the depolymerizing effect of the aldehyde. The action of HNE could be attributed to its affinity for sulphydryl groups, which are essential in maintaining tubulin and actin both in the polymerized form.

16.
Cell Biochem Funct ; 10(1): 19-26, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1576726

RESUMO

The molecular structure of aldehydes is closely related to their antimicrotubular effect. Morphological modifications of the microtubular system in living cells after incubation with certain aldehydes are consistent with biochemical alterations detected in previous research. The microtubular arrangement was visualized by an immunofluorescence technique with antitubulin antibodies, while the content of tubulin in the cells was evaluated by a colchicine binding assay. 2-Nonenal behaved similarly to 4-hydroxynonenal, a lipid peroxidation product, disorganizing microtubular network in 3T3 fibroblasts and decreasing the amounts of tubulin able to bind labelled colchicine. Nonanal did not significantly impair the tubulin characteristics in the cells, despite the fact that it has been shown to be active on the purified microtubular system; benzaldehyde was ineffective. This would appear to explain the mechanisms of interaction of aliphatic aldehydes which might be suitable for use as antimicrotubular drugs.


Assuntos
Aldeídos/farmacologia , Microtúbulos/efeitos dos fármacos , Tubulina (Proteína)/análise , Células 3T3 , Animais , Benzaldeídos/farmacologia , Sobrevivência Celular , Colchicina/metabolismo , Imunofluorescência , Imuno-Histoquímica , Camundongos
17.
Res Commun Chem Pathol Pharmacol ; 73(2): 131-44, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1686118

RESUMO

Some aldehydes have previously been shown to alter the microtubular system in a concentration-dependent manner. This paper examines the effects of taxol on the impairment of in vitro functionality of microtubular protein and of cytoplasmic microtubules by C-9 aliphatic aldehydes. Taxol-induced polymerization was inhibited by aldehydes in a similar way to GTP-induced polymerization, even though to a different degree. The addition of taxol restored the ability of aldehyde-impaired tubulin to polymerize, but only in the presence of nonanal. Colchicine binding activity in the presence of taxol was slightly modified by aldehydes at 20 degrees C, while it increased at 37 degrees C, compared to controls. Immunofluorescence showed a low disruption of microtubules in fibroblasts incubated with aldehydes and pretreated with taxol, probably as a consequence of its stabilizing activity. Anyway, aldehydes studied behaved differently, indicating a structure-activity relationship.


Assuntos
Aldeídos/farmacologia , Alcaloides/farmacologia , Proteínas dos Microtúbulos/metabolismo , Microtúbulos/efeitos dos fármacos , Células 3T3 , Animais , Sítios de Ligação , Colchicina/metabolismo , Guanosina Trifosfato/farmacologia , Camundongos , Proteínas dos Microtúbulos/química , Microtúbulos/metabolismo , Paclitaxel , Polímeros , Relação Estrutura-Atividade , Temperatura , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
18.
Chem Biol Interact ; 78(2): 183-91, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2040023

RESUMO

4-Hydroxynonenal is one of the main breakdown products of lipid peroxidation. It has an antiproliferative effect, which may partly be the consequence of an interaction with cytoskeletal structures. Its effects on microtubular protein are compared with those of homologous aldehydes with the same number of carbon atoms, and with that of benzaldehyde. Unlike the other aliphatic aldehydes, this latter aldehyde does not impair microtubular functions at every concentration in the range. Nonanal has the greatest effect on tubulin polymerization, whereas it only slightly impairs colchicine binding activity. 2-Nonenal and 4-hydroxynonenal have less inhibiting effect on tubulin polymerization; their effect on colchicine binding activity is dose-dependent. The targets of 4-hydroxynonenal on tubulin are -SH groups; the action mechanism of other aldehydes has not yet been identified.


Assuntos
Aldeídos/química , Proteínas dos Microtúbulos/química , Animais , Benzaldeídos/química , Bovinos , Colchicina/metabolismo , Cisteína/química , Técnicas In Vitro , Mercaptoetanol/química , Oxirredução , Ligação Proteica
19.
Res Commun Chem Pathol Pharmacol ; 70(2): 143-53, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2277863

RESUMO

Calvatic acid (p-carboxyphenylazoxycyanide) is an antibiotic containing an azoxycyano group that displays carcinostatic activity. In the present work it has been shown that in AH-130 hepatoma and K562 leukemia cells the antibiotic, at low concentration, decreases ornithine decarboxylase (ODC) levels. The change depends on two summative effects of the drug, impairment of overall protein synthesis and inhibition of enzyme activity. Some analogs of calvatic acid have been tested in order to gain more insight into the structure-activity relationship. The decarboxylated derivative phenylazoxycyanide proved to be more effective in reducing protein synthesis and ODC activity in the whole tumor cells. The rapidly growing K562 cells displayed high sensitivity to this compound. Calvatic acid analogs devoid of the cyano group were less effective on the same parameters.


Assuntos
Antibacterianos/farmacologia , Leucemia Eritroblástica Aguda/enzimologia , Neoplasias Hepáticas Experimentais/enzimologia , Inibidores da Ornitina Descarboxilase , Animais , Benzoatos/farmacologia , Masculino , Nitrilas/farmacologia , Biossíntese de Proteínas , Ratos , Ratos Endogâmicos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
20.
Cell Biochem Funct ; 8(2): 99-105, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2190709

RESUMO

4-Hydroxynonenal, which is one of the most important products of lipid peroxidation, alters microtubular organization and structure in 3T3 fibroblasts. Changes in cell shape and the disappearance of microtubules are observed by immunofluorescence after incubation with the aldehyde, and the colchicine binding activity of tubulin from 3T3 cells is modified. Moreover, the aldehyde determines a decrease in the ability of purified tubulin to polymerize and to bind colchicine. These effects may be related to the interaction of the aldehyde with functional -SH groups of tubulin which are necessary for protein integrity and functions. Indeed, the addition of cysteine protects against the damaging effects of the aldehyde.


Assuntos
Aldeídos/farmacologia , Compostos de Sulfidrila/metabolismo , Tubulina (Proteína)/metabolismo , Animais , Bovinos , Linhagem Celular , Colchicina/metabolismo , Cisteína/metabolismo , Imunofluorescência , Camundongos
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