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1.
Breast Cancer Res Treat ; 176(3): 579-589, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31054032

RESUMO

PURPOSE: Breast cancer survivorship care plans (SCP) have limited content addressing women's health issues. This trial tested if young breast cancer survivors who receive a web-based, women's health SCP were more likely to improve on at least one of the four targeted issues (hot flashes, fertility-related concerns, contraception, and vaginal symptoms) compared to attention controls. METHODS: A randomized controlled trial recruited female survivors ages 18-45 at diagnosis, 18-50 at enrollment, completed primary cancer treatment, and had a significant women's health issue: moderate or higher fertility-related concerns; ≥ 4 hot flashes/day with ≥ 1 of moderate severity; ≥ 1 moderate vaginal atrophy symptoms; or not contracepting/using less effective methods. Survivors underwent stratified, block randomization with equal allocation to intervention and control groups. The intervention group accessed the online SCP; controls accessed curated resource lists. In intention-to-treat analysis, the primary outcome of improvement in at least one issue by 24 weeks was compared by group. RESULTS: 182 participants (86 intervention, 96 control), mean age 40.0 ± 5.9 and 4.4 ± 3.2 years since diagnosis, were randomized. 61 intervention group participants (70.9%) improved, compared to 55 controls (57.3%) (OR 1.82, 95% CI 0.99-3.4, p = 0.057). The following issue-specific improvements were observed in the intervention versus control arms: fertility-related concerns (27.9% vs. 14.6%, OR 2.3, 95% CI 1.1-4.8); hot flashes (58.5% vs. 55.8%, OR 1.1, 95% CI 0.57-2.2); vaginal symptoms (42.5% vs. 40.7%, OR 1.1, 95% CI 0.6-2.0); contraception (50% vs. 42.6%, OR 1.4, 95% CI 0.74-2.5). CONCLUSIONS: In young breast cancer survivors, a novel, web-based SCP did not result in more change in the primary outcome of improvement in at least one of the four targeted women's health issues, than the attention control condition. The intervention was associated with improved infertility concerns, supporting efficacy of disseminating accessible, evidence-based women's health information to this population.


Assuntos
Neoplasias da Mama/epidemiologia , Sobreviventes de Câncer , Seguro Saúde , Internet , Sobrevivência , Saúde da Mulher , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Comorbidade , Feminino , Seguimentos , Pessoal de Saúde , Humanos , Pessoa de Meia-Idade , Razão de Chances , Qualidade de Vida , Inquéritos e Questionários , Estados Unidos/epidemiologia
2.
Contemp Clin Trials ; 77: 27-36, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30553078

RESUMO

BACKGROUND: Young breast cancer survivors (YBCS) have unmet needs for managing hot flashes, fertility-related concerns, sexual health, and contraception. PURPOSE: Describe the design and participant characteristics of a randomized controlled trial testing the efficacy of the survivorship care plan on reproductive health (SCP-R) intervention on improving hot flashes, fertility-related concerns, sexual health, and contraception in YBCS. METHODS: SCP-R is a web-based intervention with text message support encompassing evidence- based practices on four reproductive health issues. YBCS with ≥1 reproductive health issue are randomized to intervention (full SCP-R access) or attention control (access to list of online resources) arms with 24-week follow-up. The primary outcome will be improvement of at least one reproductive health issue measured by validated self-report instruments. Each YBCS nominated one healthcare provider (HCP), who can access the same materials as their patient. HCP outcomes are preparedness and confidence in discussing each issue. RESULTS: Among 318 YBCS screened, 57.2% underwent randomization. Mean age was 40.0 (SD 5.9), and mean age at cancer diagnosis was 35.6 (SD 5.4). Significant hot flashes, fertility-related concerns, vaginal symptoms, and inadequate contraception were reported by 50.5%, 50%, 46.7%, 62.1% of YBCS, respectively; 70.9% had multiple issues. Among 165 nominated HCPs, 32.7% enrolled. The majority of HCPs reported preparedness (68.5-90.7%) and confidence (50.0-74.1%) in discussing reproductive health issues with YBCS. HCPs were least likely to report preparedness or confidence in discussing fertility-related concerns. CONCLUSION: Conducting a trial for improving YBCS reproductive health online is feasible, providing a mechanism to disseminate evidence-based management.


Assuntos
Neoplasias da Mama/epidemiologia , Sobreviventes de Câncer/educação , Promoção da Saúde/métodos , Saúde Reprodutiva , Adulto , Anticoncepção/métodos , Método Duplo-Cego , Feminino , Fertilidade , Fogachos/prevenção & controle , Humanos , Pessoa de Meia-Idade , Educação de Pacientes como Assunto/métodos , Qualidade de Vida , Projetos de Pesquisa , Índice de Gravidade de Doença , Saúde Sexual , Envio de Mensagens de Texto
3.
Support Care Cancer ; 26(2): 589-595, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28913697

RESUMO

PURPOSE: Reproductive-aged breast cancer survivors (BCS) who have completed initial cancer treatment frequently want to know about their future fertility potential. The purpose of this qualitative study was to assess if the fertility-related content presented in the survivorship care plan prototype met the informational needs of post-treatment BCS and to provide an opportunity for the target audience to review and react to the proposed content and design. METHODS: We conducted and analyzed transcripts from seven focus groups with BCS to evaluate their reactions to the survivorship care plan prototype. We independently coded transcripts for consistent themes and sub-themes and used a consensus-building approach to agree on interpretation of results. RESULTS: We identified five themes that describe the post-treatment BCS' responses to the prototype survivorship care plan in the context of their informational needs and experiences: (1) the prototype's fertility-related information is relevant; (2) desire for clinical parameters to help survivors understand their infertility risk; (3) fertility-related information is important throughout survivorship; (4) evidence-based content from a neutral source is trustworthy; and (5) the recommendation to see a fertility specialist is helpful, but cost is a barrier. CONCLUSIONS: BCS have concerns and needs related to their fertility potential after initial breast cancer treatment. The evidence-based information offered in our prototype survivorship care plan was acceptable to BCS and has significant potential to address these needs. Additional primary data that identify post-cancer treatment indicators of fertility would advance this effort.


Assuntos
Neoplasias da Mama/psicologia , Sobreviventes de Câncer/psicologia , Fertilidade/fisiologia , Sobrevivência , Adulto , Neoplasias da Mama/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Pesquisa Qualitativa
4.
Neurochem Int ; 89: 243-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26271433

RESUMO

Over the last few years, we have identified an orally active, novel neuroprotective and cognition-enhancing molecule, the flavonoid fisetin. Fisetin not only has direct antioxidant activity but it can also increase the intracellular levels of glutathione, the major intracellular antioxidant. Fisetin can also activate key neurotrophic factor signaling pathways. In addition, it has anti-inflammatory activity against microglia and astrocytes and inhibits the activity of lipoxygenases, thereby reducing the production of pro-inflammatory eicosanoids and their by-products. However, key questions about its targets and brain penetration remain. In this study, we used label-free two-photon microscopy of intrinsic fisetin fluorescence to examine the localization of fisetin in living nerve cells and the brains of living mice. In cells, fisetin but not structurally related flavonols with different numbers of hydroxyl groups, localized to the nucleoli suggesting that key targets of fisetin may reside in this organelle. In the mouse brain, following intraperitoneal injection and oral administration, fisetin rapidly distributed to the blood vessels of the brain followed by a slower dispersion into the brain parenchyma. Thus, these results provide further support for the effects of fisetin on brain function. In addition, they suggest that label-free two-photon microscopy may prove useful for studying the intracellular and tissue distribution of other intrinsically-fluorescent flavonoids.


Assuntos
Flavonoides/análise , Hipocampo/química , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Imagem Molecular/métodos , Neurônios/química , Animais , Encéfalo/efeitos dos fármacos , Células Cultivadas , Flavonoides/administração & dosagem , Flavonóis , Hipocampo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos
5.
Artigo em Inglês | MEDLINE | ID: mdl-30766696

RESUMO

Female sexual dysfunction occurs frequently in midlife breast cancer survivors (BCS) and encompasses problems with sexual desire, interest, arousal, orgasm and genitopelvic pain. Although common, sexual problems are under-diagnosed and under-treated in BCS. The objective of this review was to assess primary studies that intervene on sexual dysfunction in BCS. In February 2015, PubMed, SCOPUS, CINAHL, COCHRANE and Web of Science databases were systematically searched for randomized controlled clinical trials (RCTs) of vaginal (lubricants, moisturizers, estrogens, dehydroepiandrosterone [DHEA], testosterone, vibrators, dilators), systemic (androgens, anti-depressants, flibanserin, ospemifene), physical therapy (physical activity, pelvic floor training), counseling and educational interventions on sexual function in BCS. Observational studies of vaginal interventions were also included due to the paucity of RCTs. The search yielded 1414 studies, 34 of which met inclusion criteria. Both interventions and outcomes, measured by 31 different sexual function scales, were heterogeneous, and therefore data were not pooled. The review found that regular and prolonged use of vaginal moisturizers was effective in improving vaginal dryness, dyspareunia, and sexual satisfaction. Educational and counseling interventions targeting sexual dysfunction showed consistent improvement in various aspects of sexual health. No consistent improvements in sexual health were observed with physical activity, transdermal testosterone or hot flash interventions. There was a lack of BCS-specific data on vaginal lubricants, vibrators, dilators, pelvic floor therapy, flibanserin or ospemifene. Overall, the quality of evidence for these studies was moderate to very low. Because each of the interventions with BCS data had limited efficacy, clinical trials to test novel interventions are needed to provide evidence-based clinical recommendations and improve sexual function in BCS.

6.
Aging Cell ; 13(2): 379-90, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24341874

RESUMO

Alzheimer's disease (AD) is the most common type of dementia. It is the only one of the top ten causes of death in the USA for which prevention strategies have not been developed. Although AD has traditionally been associated with the deposition of amyloid ß plaques and tau tangles, it is becoming increasingly clear that it involves disruptions in multiple cellular systems. Therefore, it is unlikely that hitting a single target will result in significant benefits to patients with AD. An alternative approach is to identify molecules that have multiple biological activities that are relevant to the disease. Fisetin is a small, orally active molecule which can act on many of the target pathways implicated in AD. We show here that oral administration of fisetin to APPswe/PS1dE9 double transgenic AD mice from 3 to 12 months of age prevents the development of learning and memory deficits. This correlates with an increase in ERK phosphorylation along with a decrease in protein carbonylation, a marker of oxidative stress. Importantly, fisetin also reduces the levels of the cyclin-dependent kinase 5 (Cdk5) activator p35 cleavage product, p25, in both control and AD brains. Elevated levels of p25 relative to p35 cause dysregulation of Cdk5 activity leading to neuroinflammation and neurodegeneration. These fisetin-dependent changes correlate with additional anti-inflammatory effects, including alterations in global eicosanoid synthesis, and the maintenance of markers of synaptic function in the AD mice. Together, these results suggest that fisetin may provide a new approach to the treatment of AD.


Assuntos
Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Cognição/efeitos dos fármacos , Flavonoides/farmacologia , Inflamação/patologia , Proteínas do Tecido Nervoso/metabolismo , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Animais , Ácido Araquidônico/metabolismo , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Biomarcadores/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Flavonóis , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Hipocampo/patologia , Humanos , Inflamação/complicações , Inflamação/metabolismo , Inflamação/fisiopatologia , Memória/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Estresse Oxidativo/efeitos dos fármacos , Fosfotransferases , Carbonilação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Receptores Toll-Like/metabolismo
7.
Alzheimers Res Ther ; 5(3): 25, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23673233

RESUMO

INTRODUCTION: Despite years of research, there are no disease-modifying drugs for Alzheimer's disease (AD), a fatal, age-related neurodegenerative disorder. Screening for potential therapeutics in rodent models of AD has generally relied on testing compounds before pathology is present, thereby modeling disease prevention rather than disease modification. Furthermore, this approach to screening does not reflect the clinical presentation of AD patients which could explain the failure to translate compounds identified as beneficial in animal models to disease modifying compounds in clinical trials. Clearly a better approach to pre-clinical drug screening for AD is required. METHODS: To more accurately reflect the clinical setting, we used an alternative screening strategy involving the treatment of AD mice at a stage in the disease when pathology is already advanced. Aged (20-month-old) transgenic AD mice (APP/swePS1ΔE9) were fed an exceptionally potent, orally active, memory enhancing and neurotrophic molecule called J147. Cognitive behavioral assays, histology, ELISA and Western blotting were used to assay the effect of J147 on memory, amyloid metabolism and neuroprotective pathways. J147 was also investigated in a scopolamine-induced model of memory impairment in C57Bl/6J mice and compared to donepezil. Details on the pharmacology and safety of J147 are also included. RESULTS: Data presented here demonstrate that J147 has the ability to rescue cognitive deficits when administered at a late stage in the disease. The ability of J147 to improve memory in aged AD mice is correlated with its induction of the neurotrophic factors NGF (nerve growth factor) and BDNF (brain derived neurotrophic factor) as well as several BDNF-responsive proteins which are important for learning and memory. The comparison between J147 and donepezil in the scopolamine model showed that while both compounds were comparable at rescuing short term memory, J147 was superior at rescuing spatial memory and a combination of the two worked best for contextual and cued memory. CONCLUSION: J147 is an exciting new compound that is extremely potent, safe in animal studies and orally active. J147 is a potential AD therapeutic due to its ability to provide immediate cognition benefits, and it also has the potential to halt and perhaps reverse disease progression in symptomatic animals as demonstrated in these studies.

8.
Biochem Pharmacol ; 85(12): 1816-26, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23618921

RESUMO

Glutathione (GSH) and GSH-associated metabolism provide the major line of defense for the protection of cells from various forms of toxic stress. GSH also plays a key role in regulating the intracellular redox environment. Thus, maintenance of GSH levels is developing into an important therapeutic objective for the treatment of a variety of diseases. Among the transcription factors that play critical roles in GSH metabolism are NF-E2-related factor 2 (Nrf2) and activating transcription factor 4 (ATF4). Thus, compounds that can upregulate these transcription factors may be particularly useful as treatment options through their effects on GSH metabolism. We previously showed that the flavonoid fisetin not only increases basal levels of GSH but also maintains GSH levels under oxidative stress conditions. However, the mechanisms underlying these effects have remained unknown until now. Here we show that fisetin rapidly increases the levels of both Nrf2 and ATF4 as well as Nrf2- and ATF4-dependent gene transcription via distinct mechanisms. Although fisetin greatly increases the stability of both Nrf2 and ATF4, only the effect on ATF4 is dependent on protein kinase activity. Using siRNA we found that ATF4, but not Nrf2, is important for fisetin's ability to increase GSH levels under basal conditions whereas both ATF4 and Nrf2 appear to cooperate to increase GSH levels under oxidative stress conditions. Based upon these results, we hypothesize that compounds able to increase GSH levels via multiple mechanisms, such as fisetin, will be particularly effective for maintaining GSH levels under a variety of different stresses.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Flavonoides/farmacologia , Glutationa/biossíntese , Fator 2 Relacionado a NF-E2/metabolismo , Fator 4 Ativador da Transcrição/fisiologia , Animais , Linhagem Celular Transformada , Flavonóis , Camundongos , Fator 2 Relacionado a NF-E2/fisiologia , Estresse Oxidativo/fisiologia
9.
PLoS One ; 6(6): e21226, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21738623

RESUMO

The elevated glycation of macromolecules by the reactive dicarbonyl and α-oxoaldehyde methylglyoxal (MG) has been associated with diabetes and its complications. We have identified a rare flavone, fisetin, which increases the level and activity of glyoxalase 1, the enzyme required for the removal of MG, as well as the synthesis of its essential co-factor, glutathione. It is shown that fisetin reduces two major complications of diabetes in Akita mice, a model of type 1 diabetes. Although fisetin had no effect on the elevation of blood sugar, it reduced kidney hypertrophy and albuminuria and maintained normal levels of locomotion in the open field test. This correlated with a reduction in proteins glycated by MG in the blood, kidney and brain of fisetin-treated animals along with an increase in glyoxalase 1 enzyme activity and an elevation in the expression of the rate-limiting enzyme for the synthesis of glutathione, a co-factor for glyoxalase 1. The expression of the receptor for advanced glycation end products (RAGE), serum amyloid A and serum C-reactive protein, markers of protein oxidation, glycation and inflammation, were also increased in diabetic Akita mice and reduced by fisetin. It is concluded that fisetin lowers the elevation of MG-protein glycation that is associated with diabetes and ameliorates multiple complications of the disease. Therefore, fisetin or a synthetic derivative may have potential therapeutic use for the treatment of diabetic complications.


Assuntos
Complicações do Diabetes/prevenção & controle , Diabetes Mellitus/tratamento farmacológico , Flavonoides/uso terapêutico , Glicosilação/efeitos dos fármacos , Aldeído Pirúvico/metabolismo , Animais , Ansiedade/tratamento farmacológico , Linhagem Celular , Diabetes Mellitus/metabolismo , Flavonóis , Camundongos , Camundongos Endogâmicos C57BL , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/metabolismo , Proteína Amiloide A Sérica/metabolismo
10.
PLoS One ; 4(7): e6313, 2009 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-19621078

RESUMO

BACKGROUND AND AIMS: Celiac sprue is a life-long disease characterized by an intestinal inflammatory response to dietary gluten. A gluten-free diet is an effective treatment for most patients, but accidental ingestion of gluten is common, leading to incomplete recovery or relapse. Food-grade proteases capable of detoxifying moderate quantities of dietary gluten could mitigate this problem. METHODS: We evaluated the gluten detoxification properties of two food-grade enzymes, aspergillopepsin (ASP) from Aspergillus niger and dipeptidyl peptidase IV (DPPIV) from Aspergillus oryzae. The ability of each enzyme to hydrolyze gluten was tested against synthetic gluten peptides, a recombinant gluten protein, and simulated gastric digests of whole gluten and whole-wheat bread. Reaction products were analyzed by mass spectrometry, HPLC, ELISA with a monoclonal antibody that recognizes an immunodominant gluten epitope, and a T cell proliferation assay. RESULTS: ASP markedly enhanced gluten digestion relative to pepsin, and cleaved recombinant alpha2-gliadin at multiple sites in a non-specific manner. When used alone, neither ASP nor DPPIV efficiently cleaved synthetic immunotoxic gluten peptides. This lack of specificity for gluten was especially evident in the presence of casein, a competing dietary protein. However, supplementation of ASP with DPPIV enabled detoxification of moderate amounts of gluten in the presence of excess casein and in whole-wheat bread. ASP was also effective at enhancing the gluten-detoxifying efficacy of cysteine endoprotease EP-B2 under simulated gastric conditions. CONCLUSIONS: Clinical studies are warranted to evaluate whether a fixed dose ratio combination of ASP and DPPIV can provide near-term relief for celiac patients suffering from inadvertent gluten exposure. Due to its markedly greater hydrolytic activity against gluten than endogenous pepsin, food-grade ASP may also augment the activity of therapeutically relevant doses of glutenases such as EP-B2 and certain prolyl endopeptidases.


Assuntos
Dipeptidil Peptidase 4/metabolismo , Alimentos , Glutens/metabolismo , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Glutens/química , Hidrólise , Espectrometria de Massas , Dados de Sequência Molecular
11.
Protein Eng Des Sel ; 21(12): 699-707, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18836204

RESUMO

Due to their unique ability to cleave immunotoxic gluten peptides endoproteolytically, prolyl endopeptidases (PEPs) are attractive oral therapeutic candidates for protecting celiac sprue patients from the toxic effects of dietary gluten. Enhancing the activity and stability of PEPs under gastric conditions (low pH, high pepsin concentration) is a challenge for protein engineers. Using a combination of sequence- and structure-based approaches together with machine learning algorithms, we have identified improved variants of the Sphingomonas capsulata PEP, a target of clinical relevance. Through two rounds of iterative mutagenesis and analysis, variants with as much as 20% enhanced specific activity at pH 4.5 and 200-fold greater resistance to pepsin were identified. Our results vividly reinforce the concept that conservative changes in proteins, especially in hydrophobic residues within tightly packed regions, can profoundly influence protein structure and function in ways that are difficult to predict entirely from first principles and must therefore be optimized through iterative design and analytical cycles. Incubation with whole wheat bread under simulated gastric conditions also suggests that some variants have pharmacologically significant improvements in gluten detoxification activity.


Assuntos
Doença Celíaca/tratamento farmacológico , Engenharia de Proteínas/métodos , Serina Endopeptidases/genética , Serina Endopeptidases/uso terapêutico , Sphingomonas/enzimologia , Algoritmos , Sequência de Aminoácidos , Inteligência Artificial , Glutens/metabolismo , Modelos Moleculares , Mutação , Prolil Oligopeptidases , Conformação Proteica , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo
12.
Chem Biol ; 13(6): 649-58, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16793522

RESUMO

Celiac sprue (also known as celiac disease) is an inheritable, gluten-induced enteropathy of the upper small intestine with an estimated prevalence of 0.5%-1% in most parts of the world. The ubiquitous nature of food gluten, coupled with inadequate labeling regulations in most countries, constantly poses a threat of disease exacerbation and relapse for patients. Here, we demonstrate that a two-enzyme cocktail comprised of a glutamine-specific cysteine protease (EP-B2) that functions under gastric conditions and a PEP, which acts in concert with pancreatic proteases under duodenal conditions, is a particularly potent candidate for celiac sprue therapy. At a gluten:EP-B2:PEP weight ratio of 75:3:1, grocery store gluten is fully detoxified within 10 min of simulated duodenal conditions, as judged by chromatographic analysis, biopsy-derived T cell proliferation assays, and a commercial antigluten antibody test.


Assuntos
Doença Celíaca/enzimologia , Doença Celíaca/terapia , Cisteína Endopeptidases/metabolismo , Sequência de Aminoácidos , Doença Celíaca/imunologia , Doença Celíaca/patologia , Linhagem Celular , Proliferação de Células , Separação Celular , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/farmacologia , Epitopos/imunologia , Flavobacterium/enzimologia , Flavobacterium/genética , Glutens/química , Glutens/imunologia , Glutens/metabolismo , Humanos , Inativação Metabólica , Cinética , Dados de Sequência Molecular , Myxococcus xanthus/enzimologia , Myxococcus xanthus/genética , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia
13.
Biotechnol Bioeng ; 92(6): 674-84, 2005 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-16136593

RESUMO

Celiac Sprue is a multi-factorial disease characterized by an inflammatory response to ingested wheat gluten and similar proteins in rye and barley. Proline-rich gluten peptides from wheat, rye, and barley are relatively resistant to gastrointestinal digestion, and therefore persist in the intestinal lumen to elicit immunopathology in genetically susceptible individuals. In this study, we characterize the in vitro gluten detoxifying properties of a therapeutically promising prolyl endopeptidase from Myxococcus xanthus (MX PEP), and describe the development of a prototypical enteric-coated capsule containing a pharmacologically useful dose of this enzyme. A high-cell density fed-batch fermentation process was developed for overproduction of recombinant MX PEP in E. coli, yielding 0.25-0.4 g/L purified protein. A simple, scalable purification and lyophilization procedure was established that yields >95% pure, highly active and stable enzyme as a dry powder. The dry powder was blended with excipients and encapsulated in a hard gelatin capsule. The resulting capsule was enteric coated using Eudragit L30-D55 polymer coat, which provided sufficient resistance to gastric conditions (> 1 h in 0.01 M HCl, pH 2 with pepsin) and rapid release under duodenal conditions (15-30 min release in pH 6.0 in the presence of trypsin and chymotrypsin). In conjunction with pancreatic enzymes, MX PEP breaks down whole gluten into a product mixture that is virtually indistinguishable from that generated by the Flavobacterium meningosepticum (FM) PEP as judged by chromatographic assays. Competitive studies involving selected immunogenic peptides mixed with whole gluten reveal that both PEPs have a wide range of substrate specificity. Our results support further in vitro and in vivo evaluation of the MX PEP capsule as an oral therapeutic agent for Celiac Sprue patients.


Assuntos
Doença Celíaca/tratamento farmacológico , Glutens/metabolismo , Myxococcus xanthus/enzimologia , Serina Endopeptidases/isolamento & purificação , Serina Endopeptidases/uso terapêutico , Doença Celíaca/enzimologia , Química Farmacêutica , Chryseobacterium/enzimologia , Digestão/efeitos dos fármacos , Estabilidade Enzimática , Fermentação , Glutens/efeitos dos fármacos , Modelos Biológicos , Prolil Oligopeptidases , Serina Endopeptidases/farmacologia , Especificidade por Substrato , Comprimidos com Revestimento Entérico
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