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1.
Psychooncology ; 33(5): e6349, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38752788

RESUMO

OBJECTIVE: Non-adherence to adjuvant endocrine therapy (AET) in women with breast cancer is common and associated with medication side-effects and distress. We co-designed an Acceptance and Commitment Therapy intervention (ACTION) to enhance medication decision-making and quality of life (QoL). We undertook a pilot trial of ACTION to inform the feasibility of a phase III trial, and to examine intervention acceptability. METHODS: This was a multi-site, exploratory, two-arm, individually randomised external pilot trial. Women with early breast cancer prescribed AET were randomised (1:1) to receive usual care (UC) or UC + ACTION. The ACTION intervention comprised a remotely delivered one-to-one ACT session followed by three group sessions delivered by clinical psychologists, alongside a website containing ideas for the self-management of side effects. RESULTS: Of the 480 women screened for eligibility, 260 (54.2%) were approached and 79 (30.4%) randomised. 71 (89.9%) women provided data at 3-month and 70 (88.6%) at 6-month 40 women were randomised to receive UC + ACTION and 32 (80.0%) completed the intervention. Most (75.0%) accessed the website at least once. ACTION was acceptable to participants (Borkovec & Nau Scale: mean = 7.8 [SD = 2.7] out of 10). Signals of effectiveness in favour of the UC + ACTION arm were observed for medication adherence (Adherence Starts with Knowledge questionnaire-12), QoL (work and social adjustment scale), health-related QoL (functional assessment of cancer therapy[FACT] general and FACT-ES-19/23), distress (generalised anxiety disorder -7, patient health questionnaire-9) and psychological flexibility (valuing questionnaire). CONCLUSIONS: The ACTION intervention was acceptable to patients. There were promising signals for effectiveness on primary and secondary outcomes. A phase III randomised controlled trial is feasible. TRIAL REGISTRATION: ISRCTN12027752.


Assuntos
Terapia de Aceitação e Compromisso , Neoplasias da Mama , Tomada de Decisões , Adesão à Medicação , Qualidade de Vida , Humanos , Feminino , Neoplasias da Mama/psicologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/terapia , Projetos Piloto , Pessoa de Meia-Idade , Terapia de Aceitação e Compromisso/métodos , Idoso , Adesão à Medicação/psicologia , Adulto , Antineoplásicos Hormonais/uso terapêutico , Quimioterapia Adjuvante/psicologia
2.
Pilot Feasibility Stud ; 8(1): 33, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35135619

RESUMO

BACKGROUND: Adherence to adjuvant endocrine therapy is affected by medication side-effects and associated distress. Previous interventions focused on educating women to enhance adherence have proved minimally effective. We co-designed an Acceptance and Commitment Therapy (ACT) intervention to enhance medication decision-making and quality of life by targeting a broader range of factors, including side-effect management and psychological flexibility. This study aims to establish key trial parameters, assess the acceptability of the intervention and the extent to which it can be delivered with fidelity, and to demonstrate "proof of principle" regarding its efficacy on primary and process outcomes. METHODS: The ACTION intervention includes an individual 1:1 ACT session followed by three group sessions involving 8-10 women and two practitioner psychologists. Participants are also provided with access to a website containing evidence-based methods for self-managing side-effects. The ACT sessions were adapted during the COVID-19 pandemic to be remotely delivered via video conferencing software. To evaluate the feasibility and acceptability of this intervention, a multi-site, exploratory, two-arm, individually randomised external pilot trial with a nested qualitative study will be undertaken. Eighty women with early stage breast cancer prescribed adjuvant endocrine therapy will be randomised (1:1) to receive treatment as usual or treatment as usual plus the ACTION intervention. The planned future primary outcome is medication adherence assessed by the ASK-12 measure. Progression to a phase III RCT will be based on criteria related to recruitment and follow-up rates, acceptability to patients, competency and fidelity of delivery, and proof of principle for change in medication adherence. DISCUSSION: This external pilot trial will be used to ascertain the feasibility of undertaking a future phase III RCT to definitively evaluate an ACT-based intervention to support medication taking behaviour and quality of life in women with early stage breast cancer on adjuvant endocrine therapy. TRIAL REGISTRATION: ISRCTN: 12027752. Registered 24 December 2020, https://doi.org/10.1186/ISRCTN12027752.

3.
Toxicol Appl Pharmacol ; 239(3): 297-305, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19523481

RESUMO

UNLABELLED: Methapyrilene, [N,N-dimethyl-N'-pyridyl-N'(2-thienylmethyl)-1,2-ethanediamine] (MP) was withdrawn from, clinical use due to reported periportal hepatic necrosis and hepatocarcinogenicity in the rat, via S-oxidation of the thiophene group. In this study MP is used as a model hepatotoxin to further characterise the functional consequences of S-oxidation of the thiophene group in vivo, in rat models and in vitro, in freshly isolated rat hepatocyte suspensions. In vivo histological studies revealed the early depletion of glutathione (GSH), which was confined to the damaged periportal area, in contrast to an increase in GSH levels in the centrilobular region. Additionally, the induction of cell defence was demonstrated by an increase in the protein levels of heme-oxygenase 1 (HO-1) and glutamate cysteine ligase, catalytic subunit (GCLC) in vivo. Histological examination demonstrated that cytotoxicity progresses initially via apoptosis before an increase in necrosis over the 3-day administration. An apoptotic-like mechanism was observed in vitro via the measurement of cytochrome c release and caspase activation. CONCLUSION: This study provides evidence for a complex pathway of MP-induced hepatotoxicity which progresses through early adaptation, apoptosis, necrosis and inflammation, all underpinned by the zonal induction and depletion of GSH within the liver.


Assuntos
Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Fígado/efeitos dos fármacos , Metapirileno/toxicidade , Tiofenos/metabolismo , Animais , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Glutamato-Cisteína Ligase/biossíntese , Glutationa/metabolismo , Heme Oxigenase-1/biossíntese , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Metapirileno/farmacocinética , Necrose , Oxirredução , Ratos , Ratos Wistar
4.
J Pharmacol Exp Ther ; 326(2): 657-71, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18451316

RESUMO

Methapyrilene (MP), a 2-thiophene H(1)-receptor antagonist, is a model toxicant in the genomic and proteomic analyses of hepatotoxicity. In rats, it causes an unusual periportal necrosis that is hypothetically attributed to chemically reactive and cytotoxic metabolites. We have characterized the bioactivation of MP by hepatic microsomes and primary rat hepatocytes, and we established a possible causal linkage with cytotoxicity. Methapyrilene tritiated at C-2 of the diaminoethane moiety ([3H]MP) was metabolized via an NADPH-dependent pathway to intermediates that combined irreversibly with microsomes (rat > mouse approximately human). This binding was attenuated by the cytochrome P450 (P450) inhibitor 1-aminobenzotriazole and thiols but not by trapping agents for iminium ions and aldehydes. Reactive intermediates were trapped as thioether adducts of monooxygenated MP. Mass spectrometric and hydrogen/deuterium exchange analysis of the glutathione adduct produced by rat liver microsomes indicated that the metabolite was most probably a thioether of MP S-oxide substituted in the thiophene ring. The glutathione adduct was formed by rat hepatocytes and eliminated in bile by rats administered [3H]MP intravenously. MP produced concentration- and time-dependent cytotoxicity, depleted glutathione, and underwent irreversible binding to the hepatocytes before a significant increase in cell damage was observed. P450 inhibitors reduced turnover of the drug, production of the glutathione adduct, irreversible binding, and cytotoxicity but inhibited glutathione depletion selectively. MP underwent lesser turnover and bioactivation in mouse hepatocytes and was not cytotoxic. Analogs with phenyl and p-methoxyphenyl rings were much less hepatocytotoxic than MP. Hepatotoxicity in rats was diminished by predosing with 1-aminobenzotriazole. For the first time, a thiophene ring substituent is identified as a bioactivation-dependent toxicophore in hepatocytes.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Hepatócitos/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos H1 , Metapirileno , Microssomos Hepáticos/efeitos dos fármacos , Tiofenos/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Cromatografia Líquida de Alta Pressão , Glutationa/metabolismo , Hepatócitos/metabolismo , Antagonistas dos Receptores Histamínicos H1/química , Antagonistas dos Receptores Histamínicos H1/farmacocinética , Antagonistas dos Receptores Histamínicos H1/toxicidade , Humanos , Masculino , Metapirileno/química , Metapirileno/farmacocinética , Metapirileno/toxicidade , Camundongos , Camundongos Endogâmicos , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Ratos , Ratos Wistar , Tiofenos/química
5.
Eur J Pharmacol ; 549(1-3): 1-8, 2006 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-16979156

RESUMO

Adverse drug reactions, such as hepatotoxicity, blood dyscrasias and hypersensitivity are a major obstacle for the use and the development of new medicines. Many forms of organ-directed toxicity can arise from the bioactivation of drugs to so-called chemically reactive metabolites, which can modify tissue macromolecules. It is well established that the toxicities of model hepatotoxins, such as acetaminophen, furosemide, bromobenzene and methapyrilene can be correlated with the generation of chemically reactive metabolites, which can be detected by measurement of the irreversible binding of radiolabelled material to hepatic protein and/or the detection of stable phase II metabolites such as glutathione conjugates. The basic chemistry of the reaction of such metabolites with model nucleophiles is relatively well understood. A major challenge is to define how certain reactive intermediates may chemically modify critical proteins and how modification of specific amino acids may alter protein function which in turn may affect cell signalling, regulation, defence, function and viability. This in turn will determine whether or not bioactivation will result in a particular form of drug-induced injury. It is now clear that even relatively simple reactive intermediates can react in a discriminative manner with particular cellular proteins and even with specific amino acids within those proteins. Therefore both non-covalent, as well as covalent bonds will be important determinants of the target protein for a particular reactive metabolite. Mammalian cells have evolved numerous defence systems against reactive intermediates. Sensitive redox proteins such as Nrf-2 recognize oxidative stress and electrophilic agents. This is achieved by chemical modification of cysteine groups within keap-1, which normally forms an inactive heterodimer with Nrf-2. Modification of keap-1 releases Nrf-2 that translocates to the nucleus and effects gene transcription of a number of genes involved in the detoxication of chemically reactive metabolites. Diminution of protein function can occur by either covalent modification of nucleophilic amino acids (e.g. cysteine, lysine, histidine etc.) or oxidation of thiols, which can be reversible or irreversible. In the case of acetaminophen, more than 30 target proteins have been identified and for several of them, corresponding alterations in protein function have been defined in the context of tissue necrosis. Alternatively, protein modification may induce signalling systems which initiate cell death, an immune response or to an altered tissue genotype.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Desenho de Fármacos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Acetaminofen/efeitos adversos , Acetaminofen/química , Analgésicos não Narcóticos/efeitos adversos , Analgésicos não Narcóticos/química , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/química , Hepatopatias/prevenção & controle , Modelos Biológicos , Estrutura Molecular , Preparações Farmacêuticas/química , Tiazolidinedionas/efeitos adversos , Tiazolidinedionas/química
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