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1.
Isr Med Assoc J ; 22(2): 83-88, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32043324

RESUMO

BACKGROUND: Rapid and selective bromelain-based enzymatic debridement provides a non-surgical alternative for the eschar removal in deep burns, which allows for early debridement of large surface areas, accurate evaluation of burn and wound depth, and the need for skin grafting. OBJECTIVES: To evaluate the efficacy of application of a bromelain-based selective enzymatic debridement (Nexobrid®) beyond the manufacturer's guidelines for use in burns > 48 hours as well as chemical, electrical, and pediatric burns, and chronic wounds. METHODS: This retrospective review included records collected between January 2017 and April 2019, from male and female patients aged 8 months to 99 years with deep burns or wounds treated with bromelain-based selective enzymatic debridement. RESULTS: Of the 33 patients who received the bromelain-based selective enzymatic debridement agent beyond the manufacturer's guidelines, 25 (76%) were observed to have successful debridement of the eschar, 8 (24%) were observed to have little effect on the burn eschar. Sixteen required further surgery after debridement. Clinical data on the use of bromelain-based selective enzymatic debridement agents are limited, but these results suggest the capacity to effectively debride burns > 48 hours (late presentation burns), use for pediatrics and for chemical and electrical burns, and apply to hard to heal full thickness chronic wounds. CONCLUSIONS: Bromelain-based selective enzymatic debridement was found to be an effective treatment modality beyond the recommended guidelines including late presentation burns and chronic wounds. This debridement method warrants further consideration when making clinical decisions concerning burn and wound care.


Assuntos
Bromelaínas/administração & dosagem , Queimaduras , Terapia Enzimática/métodos , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões , Administração Tópica , Adulto , Queimaduras/diagnóstico , Queimaduras/terapia , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Masculino , Estudos Retrospectivos , Tempo para o Tratamento , Índices de Gravidade do Trauma , Resultado do Tratamento , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/terapia
3.
Adv Exp Med Biol ; 1148: 173-199, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482500

RESUMO

Cancer treatment has greatly improved over the last 50 years, but it remains challenging in several cases. Useful therapeutic targets are normally unique peculiarities of cancer cells that distinguish them from normal cells and that can be tackled with appropriate drugs. It is now known that cell metabolism is rewired during tumorigenesis and metastasis as a consequence of oncogene activation and oncosuppressors inactivation, leading to a new cellular homeostasis typically directed towards anabolism. Because of these modifications, cells can become strongly or absolutely dependent on specific substrates, like sugars, lipids or amino acids. Cancer addictions are a relevant target for therapy, as removal of an essential substrate can lead to their selective cell-cycle arrest or even to cell death, leaving normal cells untouched. Enzymes can act as powerful agents in this respect, as demonstrated by asparaginase, which has been included in the treatment of Acute Lymphoblastic Leukemia for half a century. In this review, a short outline of cancer addictions will be provided, focusing on the main cancer amino acid dependencies described so far. Therapeutic enzymes which have been already experimented at the clinical level will be discussed, along with novel potential candidates that we propose as new promising molecules. The intrinsic limitations of their present molecular forms, along with molecular engineering solutions to explore, will also be presented.


Assuntos
Aminoácidos/química , Enzimas/farmacologia , Neoplasias/terapia , Asparaginase , Terapia Enzimática , Humanos , Neoplasias/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras
4.
Adv Exp Med Biol ; 1148: 323-343, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482505

RESUMO

We describe the rational use of enteric coated and unprotected replacement pancreatic enzymes for treatment of malabsorption due to pancreatic insufficiency and for pancreatic pain. Enteric coated formulations mix poorly with food allowing separation of enzymes and nutrients when emptying from the stomach. The site of dissolution of the enteric coating in the intestine is also unpredictable and enzymes may not be released until the distal intestine. Together, these barriers result in the lack of dose-response such that the strategy of increasing the dosage following a suboptimal effect is often ineffective. The ability to maintain the intragastric pH ≥4 with the combination of proton pump inhibitors and antacids suggests that it should be possible to reliably obtain a good response with uncoated enzymes. We also discuss the recognition, treatment and prevention of nutritional deficiencies associated with pancreatic insufficiency and recommend a test and treat strategy to identify and resolve nutritional deficits. Finally, we focus on mechanisms causing pain that may be amenable to therapy with pancreatic enzymes. Pain due to malabsorbed digestive contents can be prevented by successful therapy of malabsorption. Feedback inhibition of endogenous pancreatic secretion can prevent pain associated with pancreatic secretion but requires use of non-enteric coated formulations.


Assuntos
Dor Abdominal/terapia , Terapia Enzimática , Enzimas/farmacologia , Insuficiência Pancreática Exócrina/terapia , Humanos
5.
Biomed Pharmacother ; 112: 108725, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30970523

RESUMO

Glucarpidase, also known as carboxypeptidase G2, is a Food and Drug Administration-approved enzyme used in targeted cancer strategies such as antibody-directed enzyme prodrug therapy (ADEPT). It is also used in drug detoxification when cancer patients have excessive levels of the anti-cancer agent methotrexate. The application of glucarpidase is limited by its potential immunogenicity and limited catalytic efficiency. To overcome these pitfalls, mutagenesis was applied to the glucarpidase gene of Pseudomonas sp. strain RS-16 to isolate three novels "biobetter" variants with higher specific enzyme activity. DNA sequence analysis of the genes for the variants showed that each had a single point mutation, resulting in the amino acid substitutions: I100 T, G123S and T239 A. Km, Vmax and Kcat measurements confirmed that each variant had increased catalytic efficiency relative to wild type glucarpidase. Additionally, circular dichroism studies indicated that they had a higher alpha-helical content relative to the wild type enzyme. However, three different software packages predicted that they had reduced protein stability, which is consistent with having higher activities as a tradeoff. The novel glucarpidase variants presented in this work could pave the way for more efficient drug detoxification and might allow dose escalation during chemotherapy. They also have the potential to increase the efficiency of ADEPT and to reduce the number of treatment cycles, thereby reducing the risk that patients will develop antibodies to glucarpidase.


Assuntos
Desenho de Fármacos , Pró-Fármacos , Pseudomonas putida/genética , gama-Glutamil Hidrolase/genética , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/farmacocinética , Clonagem Molecular , Estabilidade Enzimática , Terapia Enzimática/métodos , Metotrexato/efeitos adversos , Metotrexato/farmacocinética , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Mutação Puntual , Pró-Fármacos/administração & dosagem , Pró-Fármacos/uso terapêutico , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico , gama-Glutamil Hidrolase/imunologia , gama-Glutamil Hidrolase/uso terapêutico
6.
Artif Cells Nanomed Biotechnol ; 47(1): 997-1013, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30945957

RESUMO

It is only in the last 20 years that many of the original ideas on artificial cells are being increasingly applied and extended by researchers around the world. Artificial cell has now evolved into nanomedicine, biotherapeutics, blood substitutes, drug delivery, enzyme/gene therapy, cancer therapy, cell/stem cell therapy, nanoparticles, liposomes, bioencapsulation, replicating synthetic cells, cell encapsulation/scaffold, biosorbent/immunosorbent haemoperfusion/plasmapheresis, regenerative medicine, encapsulated microbe, nanobiotechnology, nanotechnology and other areas. More futuristic research includes nanorobot, nanocomputer, multimodal locomotion delivery robot and others. This review starts with a general overview followed by specific examples in more details.


Assuntos
Células Artificiais , Terapia Enzimática/métodos , Hemoperfusão/métodos , Nanomedicina/métodos , Neoplasias/terapia , Plasmaferese/métodos , Medicina Regenerativa/métodos , Animais , Biotecnologia , Substitutos Sanguíneos , Cápsulas , Humanos , Imunoadsorventes , Lipossomos , Microbiologia , Nanopartículas , Neoplasias/genética , Transplante de Células-Tronco
8.
Int Urol Nephrol ; 51(4): 601-608, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30783888

RESUMO

PURPOSE: To evaluate the potential of ALLN-177, an orally administered, oxalate-specific enzyme therapy to reduce urine oxalate (UOx) excretion in patients with secondary hyperoxaluria. METHODS: Sixteen male and female subjects with both hyperoxaluria and a kidney stone history were enrolled in an open-label study. Subjects continued their usual diets and therapies. During a 3-day baseline period, two 24-h (24-h) urines were collected, followed by a 4-day treatment period with ALLN-177 (7,500 units/meal, 3 × day) when three 24-h urines were collected. The primary endpoint was the change in mean 24-h UOx from baseline. Safety assessments and 24-h dietary recalls were performed throughout. RESULTS: The study enrolled 5 subjects with enteric hyperoxaluria and 11 with idiopathic hyperoxaluria. ALLN-177 was well tolerated. Overall mean (SD) UOx decreased from 77.7 (55.9) at baseline to 63.7 (40.1) mg/24 h while on ALLN-177 therapy, with the mean reduction of 14 mg/24 h, (95% CI - 23.71, - 4.13). The calcium oxalate-relative urinary supersaturation ratio in the overall population decreased from a mean of 11.3 (5.7) to 8.8 (3.8) (- 2.8; 95% CI - 4.9, - 0.79). This difference was driven by oxalate reduction alone, but not any other urinary parameters. Mean daily dietary oxalate, calcium, and fluid intake recorded by frequent diet recall did not differ by study periods. CONCLUSION: ALLN-177 reduced 24-h UOx excretion, and was well tolerated. The results of this pilot study provided justification for further investigation of ALLN-177 in patients with secondary hyperoxaluria. TRIAL REGISTRATION: Clinicaltrials.gov NCT02289755.


Assuntos
Carboxiliases/uso terapêutico , Hiperoxalúria/tratamento farmacológico , Hiperoxalúria/urina , Oxalatos/urina , Administração Oral , Adulto , Idoso , Carboxiliases/administração & dosagem , Dieta , Terapia Enzimática , Feminino , Humanos , Hiperoxalúria/complicações , Cálculos Renais/complicações , Masculino , Pessoa de Meia-Idade
9.
Biomed Res Int ; 2019: 8720493, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30809548

RESUMO

Objectives: Occupational carpal tunnel syndrome (CTS) due to upper extremity overuse has in recent years been the most commonly recognized occupational disease in the Czech Republic and its prevalence has steadily increased. This pilot observation aimed to assess the effects of exercise techniques and oral enzyme therapy in automotive plant workers with early CTS. Patients and Methods: The observation comprised automotive plant assembly line workers in whom nerve conduction study revealed incipient CTS. The subjects were divided into three groups: a group practicing exercise techniques (exercising; N=15), a group receiving oral enzyme therapy (N=16), and a group of controls (N=14). Subjects in the control group were only observed without any specific intervention, which is a common procedure in incipient CTS. Throughout 9-week observation, the workers did their jobs. Prior to and after that period, the workers' CTS-related symptoms were ascertained through structured interviews with a physician and the following median nerve parameters were measured: sensory conduction velocity (SCV) and distal motor latency (DML). Results: In both the exercise and enzyme therapy groups, statistically significant decreases in the total score for symptoms were achieved (p<0.0001), unlike controls. On final examination, both treated groups demonstrated significantly increased SCV as compared with the initial values (p=0.00013 and p<0.0001, respectively); in controls, the mean SCV did not significantly change. Similarly, a statistically significant shortening of DML was noted in the enzyme therapy group (p=0.008). Conclusion: The results showed the efficiency of both exercise and oral enzyme therapy in incipient CTS. These methods may be recommended for preventing more severe forms of CTS.


Assuntos
Síndrome do Túnel Carpal/terapia , Terapia Enzimática , Terapia por Exercício , Doenças Profissionais/terapia , Adulto , Síndrome do Túnel Carpal/diagnóstico por imagem , Síndrome do Túnel Carpal/fisiopatologia , República Tcheca , Eletromiografia , Feminino , Humanos , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Doenças Profissionais/diagnóstico por imagem , Doenças Profissionais/fisiopatologia , Modalidades de Fisioterapia
10.
Eur J Pharm Sci ; 127: 79-91, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30343151

RESUMO

Recombinant glucarpidase (formerly: Carboxypeptidase G2, CPG2) is used in Antibody Directed Enzyme Prodrug Therapy (ADEPT) for the treatment of cancer. In common with many protein therapeutics, glucarpidase has a relatively short half-life in serum and, due to the need for the repeated cycles of the ADEPT, its bioavailability may be further diminished by neutralizing antibodies produced by patients. PEGylation and fusion with human serum albumin (HSA) are two approaches that are commonly employed to increase the residency time of protein therapeutics in blood, and also to increase the half-lives of the proteins in vivo. To address this stability and the immunogenicity problems, 'biobetter' glucarpidase variants, mono-PEGylated glucarpidase, and HSA fused glucarpidase by genetic fusion with albumin, were produced. Biochemical and bioactivity analyses, including anti-proliferation, bioassays, circular dichroism, and in vitro stability using human blood serum and immunoassays, demonstrated that the functional activities of the designed glucarpidase conjugates were maintained. The immunotoxicity studies indicated that the PEGylated glucarpidase did not significantly induce T-cell proliferation, suggesting that glucarpidase epitopes were masked by the PEG moiety. However, free glucarpidase and HSA-glucarpidase significantly increased T-cell proliferation compared with the negative control. In the latter case, this might be due to the type of expression system used or due to trace impurities associated with the highly purified (99.99%) recombinant HSA-glucarpidase. Both PEGylated glucarpidase and HAS-glucarpidase exhibit more stability in human serum and were more resistant to key human proteases relative to native glucarpidase. To our knowledge, this study is the first to report stable and less immunogenic glucarpidase variants produced by PEGylation and fusion with HSA. The results suggest that they may have better efficacy in drug detoxification and ADEPT, thereby improving this cancer treatment strategy.


Assuntos
Anticorpos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacologia , Metotrexato/farmacologia , Polietilenoglicóis/administração & dosagem , Pró-Fármacos/administração & dosagem , Albumina Sérica Humana/administração & dosagem , gama-Glutamil Hidrolase/administração & dosagem , Anticorpos/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Terapia Enzimática , Humanos , Hidrólise , Leucócitos Mononucleares/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Polietilenoglicóis/química , Pró-Fármacos/química , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Albumina Sérica Humana/química , Albumina Sérica Humana/genética , Linfócitos T/efeitos dos fármacos , gama-Glutamil Hidrolase/química
11.
Bull Math Biol ; 80(12): 3184-3226, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30291591

RESUMO

We propose a mathematical model to describe enzyme-based tissue degradation in cancer therapies. The proposed model combines the poroelastic theory of mixtures with the transport of enzymes or drugs in the extracellular space. The effect of the matrix-degrading enzymes on the tissue composition and its mechanical response are accounted for. Numerical simulations in 1D, 2D and axisymmetric (3D) configurations show how an injection of matrix-degrading enzymes alters the porosity of a biological tissue. We eventually exhibit numerically the main consequences of a matrix-degrading enzyme pretreatment in the framework of chemotherapy: the removal of the diffusive hindrance to the penetration of therapeutic molecules in tumors and the reduction of interstitial fluid pressure which improves transcapillary transport. Both effects are consistent with previous biological observations.


Assuntos
Terapia Enzimática , Modelos Biológicos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Algoritmos , Animais , Fenômenos Biomecânicos , Simulação por Computador , Elasticidade , Líquido Extracelular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Humanos , Modelos Lineares , Conceitos Matemáticos , Dinâmica não Linear , Porosidade , Pressão
12.
Cell Chem Biol ; 25(10): 1255-1267.e8, 2018 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-30146240

RESUMO

In this study we developed an efficient method to prepare glycoengineered ß-N-acetylhexosaminidase containing multiple mannose-6-phosphates (M6Ps) by combining genetic code expansion with bioorthogonal ligation techniques. We found that multiple M6P-conjugated enzymes were produced with a high efficiency by using combined techniques. Importantly, glycoengineered enzymes entered lysosomes of patient-derived primary cells, which lack endogenous lysosomal ß-N-acetylhexosaminidase, more readily than commercialized human ß-hexosaminidase. Moreover, glycoengineered enzymes successfully removed GM2-ganglioside stored in lysosomes of diseased cells, indicating that its activity is restored in diseased cells. We also synthesized and applied a lysosome-targeting fluorogenic substrate to monitor endogenous and supplemental glycoengineered ß-N-acetylhexosaminidase activities in lysosomes. The results of this study indicate that the present strategy, which relies on genetic code expansion and bioorthogonal ligation techniques, is highly attractive to generate multi-M6P-containing lysosomal enzymes that can be used to study lysosomal storage disorders associated with lysosomal enzyme deficiencies.


Assuntos
Gangliosídeo G(M2)/metabolismo , Doenças por Armazenamento dos Lisossomos/tratamento farmacológico , Lisossomos/enzimologia , Manosefosfatos/uso terapêutico , Engenharia de Proteínas/métodos , beta-N-Acetil-Hexosaminidases/uso terapêutico , Animais , Linhagem Celular , Células Cultivadas , Terapia Enzimática , Feminino , Células HEK293 , Humanos , Doenças por Armazenamento dos Lisossomos/enzimologia , Doenças por Armazenamento dos Lisossomos/metabolismo , Doenças por Armazenamento dos Lisossomos/patologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/patologia , Masculino , Manosefosfatos/química , Manosefosfatos/genética , Camundongos , Modelos Moleculares , Células NIH 3T3 , beta-N-Acetil-Hexosaminidases/química , beta-N-Acetil-Hexosaminidases/genética
13.
Food Funct ; 9(9): 4642-4650, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30156254

RESUMO

Strategies to avoid lactose malabsorption, which affects 70% of the world's population, are focused on the restriction of milk and dairy products or the use of non-human ß-galactosidases or probiotics endowed with ß-galactosidase activity added at mealtime. Our evaluation of a commercial blend of probiotics and enzymes (protease, lactase, lipase and amylase) and its potential application in lactase non-persistence management is described in this work. Recommended amounts (460-1000 mg) of the commercial probiotics-enzyme blend were shown to be adequate for performing in vitro lactose hydrolysis in standard solutions (0.25-5%) and commercial dairy products, namely milks (5% lactose) and yogurts (3% lactose), reaching hydrolysis values between 44 and 96%. According to these percentages, the use of the enzymatic preparation would guarantee the intake of less than 12 g, the recommendation of the EFSA for lactose intolerance. Furthermore, formation of prebiotic galactooligosaccharides was also detected, increasing the potential benefits of the enzymatic preparation in the gastrointestinal system.


Assuntos
Amilases/química , Lactase/química , Intolerância à Lactose/tratamento farmacológico , Lipase/química , Peptídeo Hidrolases/química , Probióticos/química , Amilases/administração & dosagem , Suplementos Nutricionais/análise , Digestão , Terapia Enzimática , Trato Gastrointestinal/metabolismo , Humanos , Lactase/administração & dosagem , Lactose/química , Lactose/metabolismo , Intolerância à Lactose/metabolismo , Lipase/administração & dosagem , Peptídeo Hidrolases/administração & dosagem , Probióticos/administração & dosagem
14.
J Med Food ; 21(11): 1120-1128, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30156436

RESUMO

Functional dyspepsia (FD) is a highly prevalent disorder having nonspecific symptoms and varied pathophysiology. Its treatment remains a challenge as therapeutic options are limited, unsatisfactory, and elusive. Thus, safety and efficacy of DigeZyme®, a proprietary multienzyme complex (MEC), was evaluated as a dietary supplement in FD patients. In this randomized, double-blind, placebo-controlled, parallel-group study, 40 patients were randomly assigned (1:1 ratio) to receive either MEC (50 mg, TID; n = 20) or placebo (n = 20) for 60 days. Reports of adverse or serious adverse events (AEs), abnormal results of vital signs, abnormal findings during physical examination, and abnormal laboratory investigations were monitored closely. Efficacy measures were change in Short-Form Leeds Dyspepsia Questionnaire (SF-LDQ), Nepean Dyspepsia Index-Short Form (NDI-SF), Visual Analog Scale (VAS), Clinical Global Impression Severity Rating Scale (CGI-S), and Glasgow Dyspepsia Severity Score (GDSS) at baseline and follow-up visits on day 15, 30, and 60. Supplementation with MEC was associated with statistically significant differences (P value ranging from .0401 to .0033) in all efficacy parameters compared with placebo. The between-group comparison also revealed that MEC supplement had a significantly greater effect (P < .001) versus placebo. No investigation product-related AEs were reported. There were no clinically significant abnormalities in physical findings and no statistically significant changes in biochemical and hematological parameters, vital signs, body weight, and body mass index observed between the two groups at baseline and follow-up visits. MEC supplementation represents an effective and safe alternative to manage dyspepsia symptoms in FD patients.


Assuntos
Dispepsia/terapia , Terapia Enzimática , Enzimas/administração & dosagem , Adolescente , Adulto , Idoso , Método Duplo-Cego , Dispepsia/metabolismo , Enzimas/efeitos adversos , Enzimas/química , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
15.
J Dig Dis ; 19(11): 650-656, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30101562

RESUMO

Post-prandial gastrointestinal symptoms such as diarrhea, abdominal distension, flatulence, bloating and a feeling of fullness are common complaints of often unknown etiology and pathogenesis. There is a long history of trials reporting the successful use of products containing a variety of combinations of digestive enzymes including a number of randomized placebo-controlled trials. We provide a narrative review of studies describing the use of multi-digestive enzymes for symptoms consistent with irritable bowel syndrome. We describe clinical trials reported over the past 60 years including double-blinded randomized, placebo-controlled studies and recent trials that focused on post-prandial diarrhea consistent with diarrhea-predominant irritable bowel syndrome. Disaccharidase deficiencies or deficiencies of other carbohydrate digesting enzymes were excluded. Worldwide studies have generally reported success with multi-enzyme preparations although none used a factorial design to identify subgroups or attempted to link specific symptom responses to specific components of therapy. Although there is a long history of the successful use of multi-enzyme preparations for post-prandial symptoms consistent with irritable bowel syndrome, long-term studies using validated scoring systems and factorial designs are needed to confirm the results for specific symptoms and the components of the combination drugs received.


Assuntos
Terapia Enzimática/métodos , Fármacos Gastrointestinais/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Humanos , Síndrome do Intestino Irritável/fisiopatologia , Pâncreas/fisiopatologia , Período Pós-Prandial
16.
PLoS One ; 13(7): e0198596, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29990322

RESUMO

BACKGROUND: Cytotoxic neural stem cells (NSCs) have emerged as a promising treatment for Medulloblastoma (MB), the most common malignant primary pediatric brain tumor. The lack of accurate pre-clinical models incorporating surgical resection and tumor recurrence limits advancement in post-surgical MB treatments. Using cell lines from two of the 5 distinct MB molecular sub-groups, in this study, we developed an image-guided mouse model of MB surgical resection and investigate intra-cavity NSC therapy for post-operative MB. METHODS: Using D283 and Daoy human MB cells engineered to express multi-modality optical reporters, we created the first image-guided resection model of orthotopic MB. Brain-derived NSCs and novel induced NSCs (iNSCs) generated from pediatric skin were engineered to express the pro-drug/enzyme therapy thymidine kinase/ganciclovir, seeded into the post-operative cavity, and used to investigate intra-cavity therapy for post-surgical MB. RESULTS: We found that surgery reduced MB volumes by 92%, and the rate of post-operative MB regrowth increased 3-fold compared to pre-resection growth. Real-time imaging showed NSCs rapidly homed to MB, migrating 1.6-fold faster and 2-fold farther in the presence of tumors, and co-localized with MB present in the contra-lateral hemisphere. Seeding of cytotoxic NSCs into the post-operative surgical cavity decreased MB volumes 15-fold and extended median survival 133%. As an initial step towards novel autologous therapy in human MB patients, we found skin-derived iNSCs homed to MB cells, while intra-cavity iNSC therapy suppressed post-surgical tumor growth and prolonged survival of MB-bearing mice by 123%. CONCLUSIONS: We report a novel image-guided model of MB resection/recurrence and provide new evidence of cytotoxic NSCs/iNSCs delivered into the surgical cavity effectively target residual MB foci.


Assuntos
Neoplasias Encefálicas/terapia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Meduloblastoma/terapia , Recidiva Local de Neoplasia/prevenção & controle , Células-Tronco Neurais/transplante , Cirurgia Assistida por Computador/métodos , Animais , Encéfalo/patologia , Encéfalo/cirurgia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Diferenciação Celular , Movimento Celular , Modelos Animais de Doenças , Terapia Enzimática/métodos , Células Epiteliais/citologia , Ganciclovir/farmacologia , Humanos , Injeções Intralesionais , Meduloblastoma/mortalidade , Meduloblastoma/patologia , Meduloblastoma/cirurgia , Camundongos , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Células-Tronco Neurais/citologia , Pró-Fármacos/farmacologia , Pele/citologia , Análise de Sobrevida , Timidina Quinase/genética , Timidina Quinase/metabolismo
17.
Dis Model Mech ; 11(8)2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29991493

RESUMO

The study of cellular metabolism has been rigorously revisited over the past decade, especially in the field of cancer research, revealing new insights that expand our understanding of malignancy. Among these insights is the discovery that various metabolic enzymes have surprising activities outside of their established metabolic roles, including in the regulation of gene expression, DNA damage repair, cell cycle progression and apoptosis. Many of these newly identified functions are activated in response to growth factor signaling, nutrient and oxygen availability, and external stress. As such, multifaceted enzymes directly link metabolism to gene transcription and diverse physiological and pathological processes to maintain cell homeostasis. In this Review, we summarize the current understanding of non-canonical functions of multifaceted metabolic enzymes in disease settings, especially cancer, and discuss specific circumstances in which they are employed. We also highlight the important role of subcellular localization in activating these novel functions. Understanding their non-canonical properties should enhance the development of new therapeutic strategies for cancer treatment.


Assuntos
Enzimas/metabolismo , Animais , Núcleo Celular/enzimologia , Terapia Enzimática , Regulação da Expressão Gênica , Humanos , Mitocôndrias/enzimologia , Modelos Biológicos , Complexos Multiproteicos/metabolismo
18.
Int J Biol Macromol ; 118(Pt A): 168-179, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29924984

RESUMO

Enzymatic dehairing as a part of the efforts for greener leather processing has reached progressive advancement with the tradition-bound tanning industry being now more receptive to cleaner processing methods due to increasing pressure from environmental groups. The dehairing mechanism is vaguely understood at present from the point of view of the enzyme specificity, which is needed for consistent and satisfactory hair removal without deleterious effect on the leather quality. Gaining insight into the dehairing specificity would help in designing efficient dehairing process. This paper attempts to review the literature pertaining to all the relevant and critical issues in detail to clearly delineate the right kind of substrate specificity required to attack only the potential targets for hair removal, and for making fine quality leather without adverse effect on other desired leather making components of the skin matrix. The gap in understanding of these critical issues is discussed with recommendation for further scientific studies in the area.


Assuntos
Enzimas/química , Remoção de Cabelo , Peptídeo Hidrolases/química , Terapia Enzimática , Humanos , Peptídeo Hidrolases/uso terapêutico , Especificidade por Substrato
19.
Nat Commun ; 9(1): 1440, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650959

RESUMO

Nanomaterials with intrinsic enzyme-like activities (nanozymes), have been widely used as artificial enzymes in biomedicine. However, how to control their in vivo performance in a target cell is still challenging. Here we report a strategy to coordinate nanozymes to target tumor cells and selectively perform their activity to destruct tumors. We develop a nanozyme using nitrogen-doped porous carbon nanospheres which possess four enzyme-like activities (oxidase, peroxidase, catalase and superoxide dismutase) responsible for reactive oxygen species regulation. We then introduce ferritin to guide nitrogen-doped porous carbon nanospheres into lysosomes and boost reactive oxygen species generation in a tumor-specific manner, resulting in significant tumor regression in human tumor xenograft mice models. Together, our study provides evidence that nitrogen-doped porous carbon nanospheres are powerful nanozymes capable of regulating intracellular reactive oxygen species, and ferritinylation is a promising strategy to render nanozymes to target tumor cells for in vivo tumor catalytic therapy.


Assuntos
Terapia Enzimática , Enzimas/metabolismo , Nanosferas/metabolismo , Nanosferas/uso terapêutico , Neoplasias Experimentais/tratamento farmacológico , Animais , Biocatálise , Carbono/química , Enzimas/química , Feminino , Ferritinas/metabolismo , Células HT29 , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanosferas/química , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Nitrogênio/química , Porosidade , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
20.
J Pediatr Gastroenterol Nutr ; 67(1): 123-130, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29543697

RESUMO

OBJECTIVE: To evaluate nutritional status and associated factors in a cystic fibrosis (CF) cohort diagnosed by newborn screening and followed up to month 24. METHODS: A prospective longitudinal multicenter study assessing nutritional status according to pancreatic status, feeding modalities, prescriptions, pulmonary outcome, and biological nutritional parameters. RESULTS: One hundred and five infants were recruited and 99 completed the study. Nutritional care management prevented undernutrition and stunting in those with exocrine pancreatic sufficiency (EPS), but affected (13/87) 15% and (21/86) 24%, respectively, of infants with exocrine pancreatic insufficiency (EPI). The logistic regression model found a positive association between both weight and length z scores "at risk" at month 24, and initial pulmonary symptoms (odds ratio [OR] 0.06, P < 0.01 and OR 0.08, P < 0.01, respectively); these symptoms were less frequent when age at first visit was earlier than 1.2 months (33% vs 67%, P = 0.02); stunting was also associated with high-calorie density intake and Staphylococcus aureus (OR 0.05, P = 0.01 and OR 0.17, P < 0.01). Pulmonary outcome did not differ according to pancreatic status; breast-feeding for at least 3 months delayed first acquisition of Pseudomonas aeruginosa. Despite sodium and fat-soluble vitamin supplementation, half of both cohorts had low urinary sodium output and half of the EPI cohort had low vitamin D levels. CONCLUSIONS: Our data shed light on the fact that stunting was more frequent than undernutrition, while both parameters involved only patients with pancreatic insufficiency. Modalities of feeding were not associated with nutritional status; breast-feeding may provide some protection against acquisition of P aeruginosa.


Assuntos
Fibrose Cística/diagnóstico , Fibrose Cística/fisiopatologia , Insuficiência Pancreática Exócrina/fisiopatologia , Transtornos do Crescimento/etiologia , Desnutrição/etiologia , Estado Nutricional , Deficiência de Vitaminas/tratamento farmacológico , Deficiência de Vitaminas/etiologia , Estatura , Peso Corporal , Aleitamento Materno , Portador Sadio/microbiologia , Pré-Escolar , Fibrose Cística/complicações , Fibrose Cística/terapia , Terapia Enzimática , Insuficiência Pancreática Exócrina/complicações , Insuficiência Pancreática Exócrina/terapia , Feminino , Transtornos do Crescimento/prevenção & controle , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Desnutrição/prevenção & controle , Triagem Neonatal , Apoio Nutricional , Estudos Prospectivos , Inibidores da Bomba de Prótons/uso terapêutico , Pseudomonas aeruginosa , Infecções Respiratórias/microbiologia , Staphylococcus aureus , Vitaminas/uso terapêutico
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