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1.
Bioorg Med Chem Lett ; 26(21): 5369-5372, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27729186

RESUMO

Tauroursodeoxycholic acid (TUDCA) is a cytoprotective ER stress inhibitor and chemical chaperone. It has therapeutic potential in a wide array of diseases but a specific macromolecular target or molecular mechanism of action remains obscure. This Letter describes an effective new synthetic approach to taurine conjugation of bile acids which we used to prepare 3α-dansyl TUDCA (4) as a probe for TUDCA actions. As a model of ER stress we used the hepatocarcinoma cell line HUH7 and stimulation with either deoxycholic acid (DCA, 200µM) or tunicamycin (5µg/ml) and measured levels of Bip/GRP78, ATF4, CHOP and XBP1s/XBP1u. Compound 4 was more effective than UDCA at inhibiting ER stress markers and had similar effects to TUDCA. In a model of cholestasis using the cytotoxic DCA to induce apoptosis, pretreatment with 4 prevented cell death similarly to TUDCA whereas the unconjugated clinically used UDCA had no effect. 3α-Dansyl TUDCA (4) appears to be a suitable reporter for TUDCA effects on ER stress and related cytoprotective activity.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Corantes Fluorescentes/química , Ácido Tauroquenodesoxicólico/farmacologia , Animais , Chaperona BiP do Retículo Endoplasmático , Humanos
2.
Bioorg Med Chem Lett ; 23(6): 1693-8, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23416011

RESUMO

Celecoxib is a COX-2 inhibitor drug that can be used to reduce the risk of colorectal adenocarcinoma. Glucocorticoids are used in the treatment of inflammatory bowel disease. A limitation to the use of both drug types is that they undergo absorption from the intestinal tract with serious side effects. The prodrug systems introduced here involve forming a nitro-substituted acylsulfonamide group in the case of celecoxib and a nitro-substituted 21-ester for the glucocorticoids. Drug release is triggered by the nitro reductase action of the colonic microflora, liberating a cyclization competent species. The release of the active parent drugs was evaluated in vitro using Clostridium perfringens and epithelial transport through Caco-2 monolayer evaluation was carried out to estimate the absorption properties of the prodrugs compared to the parental drugs.


Assuntos
Antineoplásicos/química , Budesonida/química , Nitrobenzenos/química , Prednisolona/química , Pró-Fármacos/química , Pirazóis/química , Sulfonamidas/química , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Budesonida/uso terapêutico , Budesonida/toxicidade , Células CACO-2 , Celecoxib , Permeabilidade da Membrana Celular/efeitos dos fármacos , Clostridium perfringens/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Inibidores de Ciclo-Oxigenase 2/toxicidade , Humanos , Lactonas/química , Nitrorredutases/metabolismo , Prednisolona/uso terapêutico , Prednisolona/toxicidade , Pró-Fármacos/uso terapêutico , Pró-Fármacos/toxicidade , Pirazóis/uso terapêutico , Pirazóis/toxicidade , Sulfonamidas/uso terapêutico , Sulfonamidas/toxicidade
3.
Bioorg Med Chem Lett ; 22(24): 7647-52, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23122822

RESUMO

This Letter generalizes the metabolism of the azo class of compounds by Clostridium perfringens, an anaerobe found in the human colon. A recently reported 5-aminosalicylic acid-based prednisolone prodrug was shown to release the drug when incubated with the bacteria, while the para-aminobenzoic acid (PABA) based analogue did not. Instead, it showed a new HPLC peak with a relatively close retention time to the parent which was identified by LCMS as the partially reduced hydrazine product. This Letter investigates azoreduction across a panel of substrates with varying degrees of electronic and steric similarity to the PABA-based compound. Azo compounds with an electron donating group on the azo-containing aromatic ring showed immediate disproportionation to their parent amines without any detection of hydrazine intermediates by HPLC. Compounds containing only electron withdrawing groups are partially and reversibly reduced to produce a stable detectable hydrazine. They do not disproportionate to their parent amines, but regenerate the parent azo compound. This incomplete reduction is relevant to the design of azo-based prodrugs and the toxicology of azo-based dyes.


Assuntos
Compostos Azo/metabolismo , Clostridium perfringens/química , Desenho de Fármacos , Pró-Fármacos/síntese química , Anaerobiose , Compostos Azo/química , Clostridium perfringens/metabolismo , Humanos , Estrutura Molecular , Pró-Fármacos/química , Pró-Fármacos/metabolismo
4.
Orphanet J Rare Dis ; 15(1): 103, 2020 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-32334637

RESUMO

BACKGROUND: The European Reference Networks, ERNs, are virtual networks for healthcare providers across Europe to collaborate and share expertise on complex or rare diseases and conditions. As part of the ERNs, the Clinical Patient Management System, CPMS, a secure digital platform, was developed to allow and facilitate web-based, clinical consultations between submitting clinicians and relevant international experts. The European Reference Network on Intellectual Disability, TeleHealth and Congenital Anomalies, ERN ITHACA, was formed to harness the clinical and diagnostic expertise in the sector of rare, multiple anomaly and/or intellectual disability syndromes, chromosome disorders and undiagnosed syndromic disorders. We present the first year results of CPMS use by ERN ITHACA as an example of a telemedicine strategy for the diagnosis and management of patients with rare developmental disorders. RESULTS: ERN ITHACA ranked third in telemedicine activity amongst 24 European networks after 12 months of using the CPMS. Information about 28 very rare cases from 13 different centres across 7 countries was shared on the platform, with diagnostic or other management queries. Early interaction with patient support groups identified data protection as of primary importance in adopting digital platforms for patient diagnosis and care. The first launch of the CPMS was built to accommodate the needs of all ERNs. The ERN ITHACA telemedicine process highlighted a need to customise the CPMS with network-specific requirements. The results of this effort should enhance the CPMS utility for telemedicine services and ERN-specific care outcomes. CONCLUSIONS: We present the results of a long and fruitful process of interaction between the ERN ITHACA network lead team and EU officials, software developers and members of 38 EU clinical genetics centres to organise and coordinate direct e-healthcare through a secure, digital platform. The variability of the queries in just the first 28 cases submitted to the ERN ITHACA CPMS is a fair representation of the complexity and rarity of the patients referred, but also proof of the sophisticated and variable service that could be provided through a structured telemedicine approach for patients and families with rare developmental disorders. Web-based approaches are likely to result in increased accessibility to clinical genomic services.


Assuntos
Doenças Raras , Telemedicina , Criança , Atenção à Saúde , Deficiências do Desenvolvimento , Europa (Continente) , Humanos , Doenças Raras/diagnóstico , Doenças Raras/terapia
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