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1.
Psychooncology ; 33(5): e6349, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38752788

RESUMEN

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.


Asunto(s)
Terapia de Aceptación y Compromiso , Neoplasias de la Mama , Toma de Decisiones , Cumplimiento de la Medicación , Calidad de Vida , Humanos , Femenino , Neoplasias de la Mama/psicología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/terapia , Proyectos Piloto , Persona de Mediana Edad , Terapia de Aceptación y Compromiso/métodos , Anciano , Cumplimiento de la Medicación/psicología , Adulto , Antineoplásicos Hormonales/uso terapéutico , Quimioterapia Adyuvante/psicología
2.
Pilot Feasibility Stud ; 8(1): 33, 2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35135619

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-19523481

RESUMEN

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.


Asunto(s)
Apoptosis/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Hígado/efectos de los fármacos , Metapirileno/toxicidad , Tiofenos/metabolismo , Animales , Western Blotting , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Glutamato-Cisteína Ligasa/biosíntesis , Glutatión/metabolismo , Hemo-Oxigenasa 1/biosíntesis , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hígado/metabolismo , Hígado/patología , Masculino , Metapirileno/farmacocinética , Necrosis , Oxidación-Reducción , Ratas , Ratas Wistar
4.
J Pharmacol Exp Ther ; 326(2): 657-71, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18451316

RESUMEN

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.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Hepatocitos/efectos de los fármacos , Antagonistas de los Receptores Histamínicos H1 , Metapirileno , Microsomas Hepáticos/efectos de los fármacos , Tiofenos/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Cromatografía Líquida de Alta Presión , Glutatión/metabolismo , Hepatocitos/metabolismo , Antagonistas de los Receptores Histamínicos H1/química , Antagonistas de los Receptores Histamínicos H1/farmacocinética , Antagonistas de los Receptores Histamínicos H1/toxicidad , Humanos , Masculino , Metapirileno/química , Metapirileno/farmacocinética , Metapirileno/toxicidad , Ratones , Ratones Endogámicos , Microsomas Hepáticos/metabolismo , Estructura Molecular , Ratas , Ratas Wistar , Tiofenos/química
5.
Eur J Pharmacol ; 549(1-3): 1-8, 2006 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-16979156

RESUMEN

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.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Diseño de Fármacos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Acetaminofén/efectos adversos , Acetaminofén/química , Analgésicos no Narcóticos/efectos adversos , Analgésicos no Narcóticos/química , Humanos , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/química , Hepatopatías/prevención & control , Modelos Biológicos , Estructura Molecular , Preparaciones Farmacéuticas/química , Tiazolidinedionas/efectos adversos , Tiazolidinedionas/química
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