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1.
Drug Res (Stuttg) ; 72(7): 372-377, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35767993

RESUMO

Antitumor activities of L-MTP-PE (Liposome entrapped myuramyl tripeptide phosphatidylethanolamine) in the combination treatment with chemo- or immune-therapeutic antitumor agents against various syngeneic tumors were tested.Against Meth A fibrosarcoma solid tumor system, L-MTP-PE showed slight but statistically significant elongation of survival days against 5-FU monotherapy in spite of its non-effect on tumor growth, when combined with 5-FU. Against liver metastasis model of M5076 carcinoma, L-MTP-PE showed a tendency of elongation of survival days by its single drug treatment, however, elongation with statistical significance was observed in the combination treatment with 5-FU in comparison with control group.These data suggest that L-MTP-PE seems to elongate the survival days of the solid tumor bearing mice and the liver metastasis model basically due to its saving effect on chemotherapeutic drug-induced immunosuppression. In the combination with an immunotherapeutic agent in mice, TNF production induced by another biological response modifier OK-432 was potentiated when primed with L-MTP-PE. L-MTP-PE also potentiate the antitumor effect of OK-432 possibly through the enhanced production of TNF-α. Combination of L-MTP-PE and OK-432 is considered to be a candidate for a new treatment model for cancer.


Assuntos
Neoplasias Hepáticas , Fosfatidiletanolaminas , Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Acetilmuramil-Alanil-Isoglutamina/farmacologia , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Adjuvantes Imunológicos , Animais , Portadores de Fármacos , Fluoruracila , Fatores Imunológicos , Agentes de Imunomodulação , Lipossomos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Fosfatidiletanolaminas/farmacologia , Fosfatidiletanolaminas/uso terapêutico , Picibanil
2.
Asian Pac J Cancer Prev ; 21(3): 715-720, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32212798

RESUMO

BACKGROUND: The immunomodulator mifamurtide plus a chemotherapy regimen has been shown to significantly improve the outcome in non-metastatic osteosarcoma patients. We report the results of the addition of mifamurtide to chemotherapy in newly diagnosed patients with osteosarcoma. METHODS: A total of 36 children with osteosarcoma without detectable metastasis were treated between November 2010 and April 2018 at the Ankara University Department of Pediatric Oncology. Mifamurtide was added to the chemotherapy regimen in 17 patients while the remaining 19 did not receive mifamurtide. The probabilities of metastasis and overall survival were compared between the groups. RESULTS: The 43-month survival rate was 87.5% and 89.9% in the patients who received and did not receive mifamurtide, respectively (p=0.65). Common side effects of mifamurtide were chills and fever. The addition of mifamurtide in the high-risk group with ≤95% necrosis tended to decrease the probability of distant metastasis (36.4% vs. 58.3%) (p=0.39). The time to metastasis in the group with positive surgical margins (4 months in one patient in the non-mifamurtide group, 7 and 20 months in the mifamurtide group) was also longer in the mifamurtide group. During the 43-month follow up period, median time to metastasis was longer in the mifamurtide group (20 vs. 5 months). In addition, mifamurtide plus chemotherapy decreased the risk of metastasis in the cases with primary site relapse. CONCLUSIONS: The addition of mifamurtide to chemotherapy might improve event-free survival by decreasing the probability of distant metastasis in bad histologic responders, and also by increasing the time to distant metastasis in the surgical margin positive group. Additional clinical studies are necessary to determine the long-term effects of mifamurtide on metastatic disease.
.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/uso terapêutico , Acetilmuramil-Alanil-Isoglutamina/efeitos adversos , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Adolescente , Criança , Humanos , Metástase Neoplásica , Osteonecrose/induzido quimicamente , Fosfatidiletanolaminas/efeitos adversos , Recidiva
3.
Int J Nanomedicine ; 14: 7489-7502, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571860

RESUMO

BACKGROUND: 3,5,4'-trimethoxy-trans-stilbene (BTM) is a methylated derivative of resveratrol. To improve the pharmaceutical properties of BTM, BTM loaded PEG-PE micelles (BTM@PEG-PE) were fabricated and its anti-cancer efficacy against colon cancer was evaluated. METHODS: BTM@PEG-PE micelles were prepared by the solvent evaporation method and were characterized by nuclear magnetic resonance (NMR), size, zeta potential, polymer disperse index (PDI) and transmission electron microscopy (TEM). Cellular uptake, cell viability assay, caspase-3 activity assay and flow cytometry were performed to evaluate the cell internalization and anti-cancer efficacy of BTM@PEG-PE micelles in vitro. Pharmacokinetic profiles of BTM and BTM@PEG-PE micelles were compared and in vivo anti-cancer therapeutic efficacy and safety of BTM@PEG-PE micelles on CT26 xenograft mice were evaluated. RESULTS: BTM was successfully embedded in the core of PEG-PE micelles, with a drug loading capacity of 5.62±0.80%. PEG-PE micelles facilitated BTM entering to the CT26 cells and BTM@PEG-PE micelles exerted enhanced anti-cancer efficacy against CT26 cells. BTM@PEG-PE micelles showed prolonged half-life and increased bioavailability. More importantly, BTM@PEG-PE micelles treatment suppressed tumor growth in tumor-bearing mice and prolonged survival with minimal damage to normal tissues. CONCLUSION: Altogether, the BTM@PEG-PE micelles might be a promising strategy to enhance the pharmacokinetic and pharmacodynamic potentials of BTM for colon cancer therapy.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Micelas , Fosfatidiletanolaminas/uso terapêutico , Polietilenoglicóis/uso terapêutico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Disponibilidade Biológica , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular , Neoplasias do Colo/patologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Endocitose , Feminino , Humanos , Camundongos Endogâmicos BALB C , Fosfatidiletanolaminas/efeitos adversos , Fosfatidiletanolaminas/farmacocinética , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/farmacocinética , Polímeros/química , Ratos Sprague-Dawley , Resultado do Tratamento
4.
BMJ Open ; 9(5): e025877, 2019 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-31110092

RESUMO

INTRODUCTION: The controversial results on the mifamurtide efficacy associated with chemotherapy, issued from the American INT-0133-study, in localised osteosarcomas, and the underpowered analysis performed separately in metastatic patients, should be clarified to homogenise international use of this promising drug. The European Commission has granted a marketing authorisation to mifamurtide combined with postoperative chemotherapy in localised osteosarcomas but not in metastatic patients, while the Food and Drug Administration (FDA) has denied this authorisation. METHODS AND ANALYSIS: Sarcome-13/OS2016 trial is a multicentre randomised open-label phase II trial evaluating the survival benefit of mifamurtide administered during 36 weeks in combination with postoperative chemotherapy versus chemotherapy alone, in patients >2 and ≤50 years with newly diagnosed high-risk localised or metastatic osteosarcoma. The main objective is to evaluate the impact on event-free survival (EFS) of mifamurtide on intention-to-treat population. The secondary objectives are to evaluate the impact of mifamurtide on overall survival, to evaluate the feasibility and toxicity of the planned treatment, to correlate biology/immunology with the mifamurtide efficacy/toxicity. With a total of 126 enrolled patients and 51 events, the power is 80% if mifamurtide is associated with an 18% improvement of the 3-year EFS (52%vs70%, equivalent to an HR=0.55), with a one-sided logrank test alpha=10%. As relevant historical data are available (aggregate treatment effect from the INT-0133 trial and individual data from the control group of the Sarcome-09/OS2006 trial), a Bayesian analysis is also planned. ETHICS AND DISSEMINATION: This study was approved by the 'Comité de Protection des Personnes Ile de France I' (12/06/2018), complies with the Declaration of Helsinki and French laws and regulations, and follows the International Conference on Harmonisation E6 Guideline for Good Clinical Practice. The trial results, even if they are inconclusive, as well as biological ancillary studies will be presented at appropriate international congresses and published in international peer-review journals. TRIAL REGISTRATION NUMBER: EudraCT 2017-001165-24, NCT03643133.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Fatores Imunológicos/uso terapêutico , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/uso terapêutico , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Ensaios Clínicos Fase II como Assunto , França , Humanos , Estudos Multicêntricos como Assunto , Terapia Neoadjuvante , Osteossarcoma/mortalidade , Osteossarcoma/cirurgia , Cuidados Pós-Operatórios , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida
5.
BMC Med Res Methodol ; 19(1): 85, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-31018832

RESUMO

BACKGROUND: Performing well-powered randomised controlled trials (RCTs) of new treatments for rare diseases is often infeasible. However, with the increasing availability of historical data, incorporating existing information into trials with small sample sizes is appealing in order to increase the power. Bayesian approaches enable one to incorporate historical data into a trial's analysis through a prior distribution. METHODS: Motivated by a RCT intended to evaluate the impact on event-free survival of mifamurtide in patients with osteosarcoma, we performed a simulation study to evaluate the impact on trial operating characteristics of incorporating historical individual control data and aggregate treatment effect estimates. We used power priors derived from historical individual control data for baseline parameters of Weibull and piecewise exponential models, while we used a mixture prior to summarise aggregate information obtained on the relative treatment effect. The impact of prior-data conflicts, both with respect to the parameters and survival models, was evaluated for a set of pre-specified weights assigned to the historical information in the prior distributions. RESULTS: The operating characteristics varied according to the weights assigned to each source of historical information, the variance of the informative and vague component of the mixture prior and the level of commensurability between the historical and new data. When historical and new controls follow different survival distributions, we did not observe any advantage of choosing a piecewise exponential model compared to a Weibull model for the new trial analysis. However, we think that it remains appealing given the uncertainty that will often surround the shape of the survival distribution of the new data. CONCLUSION: In the setting of Sarcome-13 trial, and other similar studies in rare diseases, the gains in power and accuracy made possible by incorporating different types of historical information commensurate with the new trial data have to be balanced against the risk of biased estimates and a possible loss in power if data are not commensurate. The weights allocated to the historical data have to be carefully chosen based on this trade-off. Further simulation studies investigating methods for incorporating historical data are required to generalise the findings.


Assuntos
Teorema de Bayes , Simulação por Computador , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Projetos de Pesquisa , Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Adjuvantes Imunológicos/uso terapêutico , Algoritmos , Grupos Controle , Humanos , Modelos Teóricos , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/uso terapêutico , Tamanho da Amostra
6.
J Pediatr Urol ; 14(2): 172.e1-172.e6, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29482891

RESUMO

INTRODUCTION: Botulinum toxin A (BTX-A) is a neurotoxin that inhibits acetylcholine release by cleaving cytosolic synaptosome-associated protein 25 (SNAP-25) and results in bladder relaxation. A BTX-A intravesical injection has been established as an effective option for treating detrusor overactivity. STUDY DESIGN: Sixty female Sprague Dawley rats were equally divided into control and experimental groups. Control Groups 1 to 3 received: BTX-A 10 units + saline instillation; hyaluronan-phosphatidylethanolamine (HA-PE) 0.5 g + saline instillation; and BTX-A 5 Uintra-detrusor injections, respectively. Treatment Groups 4 to 6 received: Alexa®594-labeled BTX-A 10 U + HA-PE 0.5 g + saline instillation; BTX-A 5 U + HA-PE 0.2-0.5 g instilled for 60 min; and BTX-A 10 U + HA-PE 0.2-0.5 g instilled for 30 min, respectively. All procedures were performed under isoflurane general anesthesia. The primary outcome of this study was the degree of SNAP-25 staining in control and experimental groups compared to Group 3 (detrusor muscle injection). Urodynamic studies were performed at baseline and at day 14 after 1% acetic acid (AA) instillation, to evaluate the maximum pressure during filling (MP) and inter-contraction intervals (ICI). Group 4 rats were examined for Alexa®594 fluorescence to demonstrate physical translocation of BTX-A-HA-PE complex. Standard histology was performed to assess the effect of HA-PE on bladder mucosa and detrusor muscle. RESULTS: Group 3 showed the least SNAP-25 staining (7.3 ± 5.0%) compared with all groups except Group 5A (12.4 ± 12.27%, P = 1.0). Group 6A, which had high HA-PE dose but a shorter instillation time, showed fairly extensive SNAP-25 staining (22.9 ± 10%). Confocal microscopy of Group 4 confirmed the presence of Alexa®594 fluorescence across the urothelium. Urodynamic parameters were not significantly different at baseline (P = 1.0). After acetic acid instillation, Group 5A showed minimal change in ICI, which was comparable to ICI in Group 3 rats. DISCUSSION: SNAP-25 staining in Group 5A was comparable to Group 3, suggesting that adequate HA-PE and instillation time allows the efficacy of this carrier mechanism to be comparable to standard intra-detrusor injections. All other groups showed significantly higher SNAP-25 staining compared to Group 3. A dose response effect was demonstrated; higher dose of HA-PE (Group 5A vs Group 5B) and longer instillation time (Group 5 vs Group 6) led to lower SNAP-25 staining. CONCLUSION: This novel method of BTX-A delivery to the bladder using a carrier (HA-PE) is promising and requires further investigation. Using a larger animal model, identifying an optimal dose of HA-PE and instillation time, and reproducing the current results are further required to validate this carrier.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Portadores de Fármacos/administração & dosagem , Ácido Hialurônico/administração & dosagem , Fosfatidiletanolaminas/uso terapêutico , Bexiga Urinaria Neurogênica/tratamento farmacológico , Bexiga Urinária/efeitos dos fármacos , Administração Intravesical , Análise de Variância , Animais , Modelos Animais de Doenças , Feminino , Fármacos Neuromusculares/administração & dosagem , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Resultado do Tratamento , Urodinâmica
7.
Mol Nutr Food Res ; 62(7): e1700637, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29396909

RESUMO

SCOPE: Recent studies have shown that omega-3 PUFAs enriched phospholipids (n-3 PUFA-PLs) have beneficial effects on memory and cognition. However, most reports only attribute the benefit to docosahexaenoic acid (DHA) and pay little attention to eicosapentaenoic acid (EPA). METHODS AND RESULTS: We investigate the effect of EPA-enriched phospholipids on cognitive deficiency in senescence-accelerated prone 8 (SAMP8) mouse. Ten-month-old SAMP8 mice are fed with 2% (w/w) EPA-enriched phosphatidylcholine/phosphatidyl ethanolamine (EPA-PC/PE; EPA:DHA = 46.8:3.01) or 2% EPA-enriched phosphatidylserine (EPA-PS; biosynthesized from EPA-PC/PE) for 8 weeks; we then test the behavioral performances in the Barnes maze test and Morris maze test; the changes of oxidative stress, apoptosis, neurotrophic factors, tau phosphorylation, and Aß pathology are also measured. The results of behavior tests indicate that both EPA-PC/PE and EPA-PS significantly improve memory and cognitive deficiency. It is found that remarkable amelioration of oxidative stress and apoptosis occurs in both EPA-PC/PE and EPA-PS groups. EPA-PS shows more ameliorative effects than EPA-PC/PE on neurotrophic activity by decreasing hyper-phosphorylation of tau and depressing the generation and accumulation of ß-amyloid peptide (Aß). CONCLUSION: These data suggest that EPA-PS exhibits better effects than EPA-PC/PE on ameliorating memory and cognitive function, which might be attributed to the phospholipid polar groups.


Assuntos
Envelhecimento , Disfunção Cognitiva/prevenção & controle , Suplementos Nutricionais , Ácido Eicosapentaenoico/uso terapêutico , Transtornos da Memória/prevenção & controle , Nootrópicos/uso terapêutico , Fosfolipídeos/uso terapêutico , Animais , Apoptose , Comportamento Animal , Encéfalo/metabolismo , Calceolariaceae/química , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos , Camundongos Mutantes , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Estresse Oxidativo , Fosfatidilcolinas/uso terapêutico , Fosfatidiletanolaminas/uso terapêutico , Fosfatidilserinas/uso terapêutico , Distribuição Aleatória
8.
Acta Pharmacol Sin ; 39(1): 132-139, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28795690

RESUMO

Cancer metastasis is responsible for over 90% of breast cancer-related deaths, and inhibiting lymph node metastasis is an option to treat metastatic disease. Herein, we report the use of IR-780-loaded polymeric micelles (IPMs) for effective photothermal therapy (PTT) of breast cancer lymphatic metastasis. The IPMs were nanometer-sized micelles with a mean diameter of 25.6 nm and had good stability in simulated physiological solutions. Under 808-nm laser irradiation, IPMs exhibited high heat-generating capability in both in vitro and in vivo experiments. After intravenous injection, IPMs specifically accumulated in the tumor and metastatic lymph nodes and penetrated into these tissues. Moreover, a single IPMs treatment plus laser irradiation significantly inhibited primary tumor growth and suppressed lymphatic metastasis by 88.2%. Therefore, IPMs are an encouraging platform for PTT applications in treatment of metastatic breast cancer.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Indóis/uso terapêutico , Metástase Linfática/prevenção & controle , Animais , Antineoplásicos/efeitos da radiação , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/efeitos da radiação , Portadores de Fármacos/uso terapêutico , Feminino , Calefação , Indóis/efeitos da radiação , Terapia a Laser/métodos , Camundongos Nus , Micelas , Tamanho da Partícula , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/efeitos da radiação , Fosfatidiletanolaminas/uso terapêutico , Fototerapia/métodos , Polietilenoglicóis/química , Polietilenoglicóis/efeitos da radiação , Polietilenoglicóis/uso terapêutico
9.
J Control Release ; 268: 92-101, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29042320

RESUMO

Myelodysplastic syndromes (MDS) are a diverse group of bone marrow disorders and clonal hematopoietic stem cell disorders characterized by abnormal blood cells, or reduced peripheral blood cell count. Recent clinical studies on combination therapy of decitabine (DAC) and arsenic trioxide (ATO) have demonstrated synergy on MDS treatment, but the treatment can cause significant side effects to patients. In addition, both drugs have to be administered on a daily basis due to their short half-lives. In addressing key issues of reducing toxic side effects and improving pharmacokinetic profiles of the therapeutic agents, we have developed a new formulation by co-packaging DAC and ATO into alendronate-conjugated bone-targeting nanoparticles (BTNPs). Our pharmacokinetic studies revealed that intravenously administered BTNPs increased circulation time up to 3days. Biodistribution analysis showed that the BTNP facilitated DAC and ATO accumulation in the bone, which is 6.7 and 7.9 times more than untargeted NP. Finally, MDS mouse model treated with BTNPs showed better restoration of complete blood count to normal level, and significantly longer median survival as compared to free drugs or untargeted NPs treatment. Our results support bone-targeted co-delivery of DAC and ATO for effective treatment of MDS.


Assuntos
Antineoplásicos/administração & dosagem , Arsenicais/administração & dosagem , Azacitidina/análogos & derivados , Síndromes Mielodisplásicas/tratamento farmacológico , Nanopartículas/administração & dosagem , Óxidos/administração & dosagem , Alendronato/administração & dosagem , Alendronato/química , Alendronato/farmacocinética , Alendronato/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Trióxido de Arsênio , Arsenicais/química , Arsenicais/farmacocinética , Arsenicais/uso terapêutico , Azacitidina/administração & dosagem , Azacitidina/química , Azacitidina/farmacocinética , Azacitidina/uso terapêutico , Células da Medula Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Decitabina , Camundongos Transgênicos , Síndromes Mielodisplásicas/metabolismo , Nanopartículas/química , Nanopartículas/uso terapêutico , Óxidos/química , Óxidos/farmacocinética , Óxidos/uso terapêutico , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/farmacocinética , Fosfatidiletanolaminas/uso terapêutico , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/uso terapêutico , Distribuição Tecidual
10.
JBI Database System Rev Implement Rep ; 15(8): 2113-2152, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28800058

RESUMO

BACKGROUND: Osteosarcoma mostly occurs during the period of rapid bone growth in children and adolescents as high-grade osteosarcomas. Current treatment recommended for high-grade non-metastatic and metastatic and/or relapsed osteosarcoma involves neoadjuvant multiagent conventional chemotherapy, followed by surgical resection of macroscopically detected tumor and postoperative adjuvant chemotherapy. However, residual micrometastatic deposits that develop following surgery have shown resistance to postoperative/adjuvant chemotherapy. Therefore, there is a critical need for more effective and innovative therapeutic approaches such as immune stimulatory agents. The most extensively studied immune stimulatory agent in the treatment of osteosarcoma is mifamurtide. The aim of this systematic review was to identify and synthesize the evidence on the effectiveness of mifamurtide in addition to standard chemotherapy on survival outcomes. OBJECTIVES: To present the best available evidence on the treatment of high-grade non-metastatic and metastatic osteosarcoma with mifamurtide in addition to standard chemotherapy. INCLUSION CRITERIA TYPES OF PARTICIPANTS: All populations of patients regardless of age, gender or ethnicity with high-grade, resectable, non-metastatic and metastatic osteosarcoma based on histological diagnosis. TYPES OF INTERVENTIONS AND COMPARATORS: This review focused on intravenous infusion of either of the pharmaceutical formulations of mifamurtide (MTP-PE or L-MTP-PE) in addition to standard chemotherapy, and the comparator was chemotherapy alone. TYPES OF STUDIES: This review considered any experimental study design including randomized controlled trials, non-randomized trials and quasi-experimental studies. OUTCOMES: The primary outcomes of interest were event-free survival, overall survival and recurrence of osteosarcoma. Secondary outcomes that were considered included health-related quality of life and any mifamurtide-related adverse events. SEARCH STRATEGY: A search for published and unpublished literature in English was undertaken (seven published literature databases, four unpublished literature databases, and three government agency and organizational websites were searched). Studies published between 1990 to June 2016 were considered. A three-step strategy was developed using MeSH terminology and keywords to ensure that all relevant studies were included related to this review. METHODOLOGICAL QUALITY: The methodological quality of included studies was assessed by two reviewers, who appraised each study independently, using a standardized Joanna Briggs Institute (JBI) critical appraisal tool. DATA EXTRACTION: Data was extracted from the studies that were identified as meeting the criteria for methodological quality using the standard JBI data extraction tool. DATA SYNTHESIS: Due to the heterogeneity of populations and interventions in available studies, meta-analysis was not possible and results are presented in narrative form. RESULTS: Three papers outlining two studies involving 802 patients evaluated the effectiveness of mifamurtide in addition of chemotherapy. Results indicated no significant difference in event-free survival between the addition of mifamurtide to standard chemotherapy regimen and chemotherapy alone, both in non-metastatic and metastatic osteosarcoma patients. There was a significant difference in progression-free survival favoring the addition of mifamurtide in pulmonary metastatic and/or relapsed osteosarcoma. There was no significant difference in overall survival between the addition of mifamurtide and chemotherapy alone in metastatic osteosarcoma; however there was a significant difference favoring the addition of mifamurtide in non-metastatic osteosarcoma patients. The addition of mifamurtide resulted in a significant difference in survival after relapse in pulmonary metastatic and/or relapsed osteosarcoma patients. Both studies reported on mifamurtide-related adverse events - the first was reported as toxicity which included haematological, hepatic, renal, gastrointestinal disorders, cardiac, rhythm and nervous system disorders, ear disorders and others (infection, fever; and performance status) in metastatic osteosarcoma patients. Results were similar across all combined treatment regimens. Although no statistical analysis was undertaken, the figures suggest there were no significant differences between the treatment regimens. In the other study, mifamurtide-related adverse events were reported as clinical toxic effects of mifamurtide in relapsed osteosarcoma, which included chills, fever and headache for the initial dose of mifamurtide, while for the subsequent doses of mifamurtide all patients reported toxicity as delayed fatigue. CONCLUSIONS: The available evidence on the effectiveness of mifamurtide in addition to a standard chemotherapy regimen for the treatment of high-grade osteosarcoma is limited and therefore no definitive conclusions can be made.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Adjuvantes Imunológicos/uso terapêutico , Tratamento Farmacológico/métodos , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/uso terapêutico , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Humanos
11.
J Control Release ; 235: 245-258, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27276066

RESUMO

The traditional drug delivery systems always suffer from the unexpected drug release during circulation and the sluggish release of drug in target site. To address the problem, an "off-on" type drug delivery system with precise control was developed in this study. Doxorubicin (DOX) was covalently conjugated to fullerene (C60) nanoaggregates via a reactive oxygen species (ROS)-sensitive thioketal linker (C60-DOX NPs), and then the hydrophilic shell (Distearoyl-sn-glycero-3-phosphoethanolamine-PEG-CNGRCK2HK3HK11, DSPE-PEG-NGR) was attached to the outer surface of C60-DOX, giving it (C60-DOX-NGR NP) excellent stability in physiological solutions and active tumor-targeting capacity. C60-DOX-NGR NPs were able to entrap DOX efficiently even at acidic environment (pH5.5) when they were "off" state. In sharp contrast, when the NPs were "on" state, a large number of ROS were generated by C60, leading to the breaking of ROS-sensitive linker, thereby enabling the burst release of DOX. The "off" or "on" state of C60-DOX-NGR NPs could be precisely remote-controlled by a 532nm laser (at a low power density) with a high spatial/temporal resolution. In the in vivo and in vitro studies, the C60-based drug delivery system with "off-on" state exhibited a high antitumor efficacy and a low toxicity to normal tissues due to its tumor-targeting ability, remote-controlled drug release property and combined therapeutic effect (photodynamic therapy combined with chemotherapy).


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Fulerenos/administração & dosagem , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/uso terapêutico , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapêutico , Feminino , Fulerenos/química , Fulerenos/farmacocinética , Fulerenos/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/farmacocinética , Fosfatidiletanolaminas/uso terapêutico , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Carga Tumoral/efeitos dos fármacos
12.
Curr Drug Deliv ; 13(8): 1351-1357, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26996369

RESUMO

This study represents a new formulation of the novel Cyanide (CN) antidote, Dimethyl trisulfide (DMTS), for intramuscular administration. This is a naturally occurring organosulfur molecule with the capability of reacting with CN more efficiently than the present sulfur donor type CN therapy of Thiosulfate (TS). Two types of micelles (PEG2000-DSPE and PEG2000-DSPE/TPGS) were prepared and tested for their ability to encapsulate the liquid, highly lipophilic and volatile drug, DMTS. The micellar encapsulation for DMTS does not only eliminate the possible muscle necrosis at the injection sites, but the rate of evaporation within the micelles is suppressed, that can provide a level of stability for the formulation. The method of micelle preparation was optimized and it was demonstrated that the PEG2000-DSPE preparation can dissolve up to 2.0 mg/ml of the antidote candidate. Keeping the injection volume minimized this could provide a maximum DMTS dose of 12.5 mg/kg. However, even this low dose of DMTS showed a remarkable in vivo therapeutic efficacy (2 X LD50 protection) in a mice model when injected intramuscularly. These in vitro and in vivo findings proved the efficacy of DMTS in combating CN intoxication, and the presented work gives valuable insight to micelle preparation and sets the bases for a more advanced future formulation of DMTS.


Assuntos
Antídotos/administração & dosagem , Cianetos/antagonistas & inibidores , Portadores de Fármacos/administração & dosagem , Sulfetos/administração & dosagem , Animais , Antídotos/química , Antídotos/uso terapêutico , Cianetos/toxicidade , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Injeções Intramusculares , Masculino , Camundongos , Micelas , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/uso terapêutico , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/uso terapêutico , Solubilidade , Sulfetos/química , Sulfetos/uso terapêutico , Vitamina E/administração & dosagem , Vitamina E/química , Vitamina E/uso terapêutico
13.
Tumour Biol ; 36(9): 6773-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25835978

RESUMO

The mortality and progression rates in osteosarcoma differ depending on the presence of metastasis. A decision model would be useful for estimating long-term effectiveness of treatment with limited clinical trial data. The aim of this study was to explore the lifetime effectiveness of the addition of mifamurtide to chemotherapy for patients with metastatic and nonmetastatic osteosarcoma. The target population was osteosarcoma patients with or without metastasis. A Markov process model was used, whose time horizon was lifetime with a starting age of 13 years. There were five health states: disease-free (DF), recurrence, post-recurrence disease-free, post-recurrence disease-progression, and death. Transition probabilities of the starting state, DF, were calculated from the INT-0133 clinical trials for chemotherapy with and without mifamurtide. Quality-adjusted life-years (QALY) increased upon addition of mifamurtide to chemotherapy by 10.5 % (10.13 and 9.17 QALY with and without mifamurtide, respectively) and 45.2 % (7.23 and 4.98 QALY with and without mifamurtide, respectively) relative to the lifetime effectiveness of chemotherapy in nonmetastatic and metastatic osteosarcoma, respectively. Life-years gained (LYG) increased by 10.1 % (13.10 LYG with mifamurtide and 11.90 LYG without mifamurtide) in nonmetastatic patients and 42.2 % (9.43 LYG with mifamurtide and 6.63 LYG without mifamurtide) in metastatic osteosarcoma patients. The Markov model analysis showed that chemotherapy with mifamurtide improved the lifetime effectiveness compared to chemotherapy alone in both nonmetastatic and metastatic osteosarcoma. Relative effectiveness of the therapy was higher in metastatic than nonmetastatic osteosarcoma over lifetime. However, absolute lifetime effectiveness was higher in nonmetastatic than metastatic osteosarcoma.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Tratamento Farmacológico , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/uso terapêutico , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Humanos , Cadeias de Markov , Modelos Estatísticos , Metástase Neoplásica , Osteossarcoma/patologia
14.
Adv Exp Med Biol ; 804: 307-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24924182

RESUMO

Bacille Calmette-Guerin (BCG) has been used for decades as an immune stimulant to treat cancer. Early work by Fidler and Kleinerman identified muramyl dipeptide (MDP) as a critical component of the BCG cell wall which retained most of the immunostimulatory properties of the native BCG. Addition of a peptide to MDP resulted in muramyl tripeptide (MTP) which allowed incorporation into liposomal membranes. The resulting pharmaceutical, liposomal muramyl tripeptide phosphatidyl ethanolamine (L-MTP-PE or mifamurtide) showed activity in preclinical models of human cancers. Phase I studies documented the safety of the compound for human administration. These trials did not reach a maximally tolerated dose (MTD), and the dose chosen for phase II trials was a biologically optimized dose, not an MTD. Phase II studies showed decreased risk of further recurrence in patients who received mifamurtide after surgical ablation of metastatic osteosarcoma. A phase III prospective randomized trial demonstrated a statistically significant reduction in the risk of death from osteosarcoma when MTP was added to systemic chemotherapy for the treatment of localized osteosarcoma. The same trial allowed treatment of patients who presented with initially metastatic disease. While the overall and event-free survival was improved in patients with metastatic osteosarcoma who received L-MTP-PE, the sample size was small and the improvement did not achieve conventional statistical significance. From 2008 to 2012, patients with metastatic and recurrent osteosarcoma were given L-MTP-PE in an expanded access trial, and the results suggest a decreased risk of subsequent recurrence and death with the inclusion of L-MTP-PE in the treatment strategy for these high-risk patients.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Lipossomos/química , Neoplasias Pulmonares/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/uso terapêutico , Acetilmuramil-Alanil-Isoglutamina/química , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Antineoplásicos/química , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Ensaios Clínicos como Assunto , Composição de Medicamentos , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/cirurgia , Osteossarcoma/mortalidade , Osteossarcoma/secundário , Osteossarcoma/cirurgia , Fosfatidiletanolaminas/química , Análise de Sobrevida , Resultado do Tratamento
15.
Biomaterials ; 35(22): 5847-61, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24746963

RESUMO

In this study, a GO@Ag nanocomposite was synthesized by chemical deposition of Ag nanoparticles onto graphene oxide (GO) through a hydro thermal reaction, and doxorubicin (DOX), one of the most effective drugs against a wide range of cancers, was employed as the model drug and linked to GO@Ag via ester bonds with a very high drug loading efficiency (∼82.0%, weight ratio of DOX/GO@Ag), then GO@Ag-DOX was functionalized by DSPE-PEG2000-NGR, giving GO@Ag-DOX with active tumor-targeting capacity and excellent stability in physiological solutions. The release profiles of DOX from GO@Ag-DOX-NGR showed strong dependences on near-infrared (NIR) laser and the SPR effect of Ag nanoparticles. Compared with free DOX in an in vivo murine tumor model, GO@Ag-DOX-NGR afforded much higher antitumor efficacy without obvious toxic effects to normal organs owing to 8.4-fold higher DOX uptake of tumor and 1.7-fold higher DOX released in tumor with NIR laser than the other tissues. Besides, in this work, GO@Ag-DOX-NGR not only served as a powerful tumor diagnostic X-ray contrast agent, but also as a strong agent for photothermal ablation of tumor, the ability of GO@Ag-DOX-NGR nanoparticles to combine the local specific chemotherapy with external photothermal therapy (PTT) significantly improved the therapeutic efficacy. GO@Ag-DOX-NGR showed excellent chem-photothermal therapeutic efficacy, tumor-targeting property, NIR laser-controlled drug releasing function and X-ray imaging ability, demonstrating that there is a great potential of GO@Ag-DOX-NGR for cancer diagnosis and therapy.


Assuntos
Grafite/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/terapia , Prata/uso terapêutico , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Grafite/química , Humanos , Hipertermia Induzida , Lasers , Camundongos , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Óxidos/química , Óxidos/uso terapêutico , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/uso terapêutico , Fototerapia , Polietilenoglicóis/química , Polietilenoglicóis/uso terapêutico , Prata/química , Tomografia Computadorizada por Raios X , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Value Health ; 16(8): 1123-32, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24326165

RESUMO

OBJECTIVES: Mifamurtide is an immune macrophage stimulant that when added to standard chemotherapy has demonstrated survival benefit for newly diagnosed osteosarcoma. The objectives of this study were to investigate the cost-effectiveness of adding mifamurtide to standard three- or four-agent chemotherapy for high-grade, resectable, nonmetastatic osteosarcoma following surgical resection and the issues of obtaining robust cost-effectiveness estimates for ultra-orphan drugs, given the shortage of data. METHODS: An economic evaluation was conducted from the perspective of the UK's National Health Service as part of the manufacturer's submission to the National Institute for Health and Care Excellence. The disease process was simplified to a transition through a series of health states, modeled by using a Markov approach. Data to inform the model were derived from patient-level data of Study INT-0133, published literature, and expert opinion. The final efficacy measure was life-years gained (LYG), and utilities were used to obtain quality-adjusted life-years (QALYs). RESULTS: For a 60-year time frame and a discount rate of 3.5% for outcomes, patients receiving mifamurtide benefited from an average additional 1.57 years of life and 1.34 QALYs, compared with patients receiving chemotherapy alone, giving an incremental cost-effectiveness ratio (ICER) of £58,737 per LYG and £68,734 per QALY. Because treatment effects were both substantial in restoring health and sustained over a very long period, the National Institute for Health and Care Excellence changed its guidance to allow a discount of 1.5% for outcomes to be applied in these special circumstances. By using this discount factor, it was found that patients receiving mifamurtide had an average additional 2.58 years of life and 2.20 QALYs compared with patients receiving chemotherapy alone, resulting in an ICER of £35,765 per LYG and £41,933 per QALY. CONCLUSION: Mifamurtide's ICER is cost-effective compared with that of other orphan and ultra-orphan drugs, for which prices and corresponding cost-effectiveness estimates are high.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Adjuvantes Imunológicos/economia , Adjuvantes Imunológicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/economia , Fosfatidiletanolaminas/uso terapêutico , Acetilmuramil-Alanil-Isoglutamina/administração & dosagem , Acetilmuramil-Alanil-Isoglutamina/economia , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Adjuvantes Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica , Análise Custo-Benefício , Humanos , Cadeias de Markov , Fosfatidiletanolaminas/administração & dosagem , Anos de Vida Ajustados por Qualidade de Vida
17.
Minerva Gastroenterol Dietol ; 57(3): 323-31, 2011 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-21769081

RESUMO

Adjustment and maintenance of body weight are the result of many process combination, that affect both the gastrointestinal system and other mechanisms in the central nervous system. Often a diet modification alone is not sufficient to guarantee significant changes in body weight. For this reason, it sometimes necessary to make other interventions, in order to help an individual to adhere to the diet as much as possible and to achieve the objectives established. The N-oleyl-phosphatidyl-ethanolamine (NOPE) is a phospholipid. It can be endogenous or exogenous, and it is present in cell membranes and in much of the food. Food intake increases its production; in fact, because of certain stimuli, it is sometimes produced by the epithelial intestine cells too. Another substance whose activity is comparable to NOPE is the epigallocatechin gallate (EGCG), an abundant catechin present in the green tea, which allows a lipid lowering and antioxidant action, and acts on energy consumption as well. The aim of our study was to evaluate the effectiveness of NOPE and EGCG pharmaceutical formulation in a population of obese women, administering the supplement twice daily before meals, for a period of 60 days. The comparison between the effectiveness of the results in a homogeneous group of patients treated with diet and placebo, allows to confirm the data reported in the literature regarding the effectiveness of the pharmaceutical formulation and the absence of side effects.


Assuntos
Antioxidantes/uso terapêutico , Depressores do Apetite/uso terapêutico , Catequina/análogos & derivados , Obesidade Mórbida/tratamento farmacológico , Fosfatidiletanolaminas/uso terapêutico , Adulto , Índice de Massa Corporal , Catequina/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
18.
Prescrire Int ; 20(115): 89, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21648206

RESUMO

The standard treatment for children and young adults with osteosarcoma consists of surgery, preceded and followed by methotrexate-based chemotherapy. Mifamurtide is an immunostimulant derived from a bacterial cell wall component. It is authorised in the European Union as an adjunct to combination chemotherapy after complete excision of non-metastatic osteosarcoma. Only one comparative, unblinded trial has been published, and its design was particularly complex. In a study population of 678 patients, adding mifamurtide to chemotherapy after tumour excision did not prolong the overall 6-year survival rate, which was about 75% with both treatments. Only serious adverse effects were collected, and they were not systematically recorded. Hypersensitivity reactions occurred in clinical trials, along with pleural and pericardial effusions, seizures, and muscle spasms. Severe hearing loss occurred in 12% of the patients treated with mifamurtide in the comparative trial, versus 7% of the other patients. In practice, given the lack of any survival benefit and the risk of serious adverse effects, it is better not to add mifamurtide to chemotherapy regimens used for treatment of osteosarcoma.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Fatores Imunológicos/efeitos adversos , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/efeitos adversos , Acetilmuramil-Alanil-Isoglutamina/efeitos adversos , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Adolescente , Criança , Humanos , Fatores Imunológicos/uso terapêutico , Fosfatidiletanolaminas/uso terapêutico , Taxa de Sobrevida , Adulto Jovem
19.
Expert Opin Pharmacother ; 12(2): 285-92, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21226638

RESUMO

INTRODUCTION: The standard treatment for osteosarcoma requires both macroscopic surgical wide resection and postoperative multi-drug chemotherapy in neoadjuvant and adjuvant settings. However, the 5-year event-free survival has remained at a plateau of 60-70% of patients with nonmetastatic osteosarcoma for more than 30 years. AREAS COVERED: Mifamurtide (liposomal muramyl tripeptide phosphatidylethanolamine; L-MTP-PE) is a new agent. L-MTP-PE is a nonspecific immunomodulator, which is a synthetic analog of a component of bacterial cell walls. L-MTP-PE activates macrophages and monocytes as a potent activator of immune response in addition to standard chemotherapy. It also improves the overall survival from 70 to 78% and results in a one-third reduction in the risk of death from osteosarcoma. This review summarizes the most recent findings about L-MTP-PE and its therapeutic application for nonmetastatic osteosarcoma. EXPERT OPINION: Recently, L-MTP-PE has been approved in Europe for the treatment of nonmetastatic osteosarcoma with chemotherapy. L-MTP-PE in combination with traditional treatment is expected to go mainstream and to be beneficial for patients with osteosarcoma. Information about potential benefit regarding mifamurtide use in the neoadjuvant setting (i.e., before surgery) and/or usefulness of L-MTP-PE in metastatic in relapsed and metastatic osteosarcoma requires analysis of expanded access and/or future clinical trials of L-MTP-PE in high-burden and low-burden situations.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Adjuvantes Imunológicos/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Fosfatidiletanolaminas/uso terapêutico , Acetilmuramil-Alanil-Isoglutamina/administração & dosagem , Acetilmuramil-Alanil-Isoglutamina/efeitos adversos , Acetilmuramil-Alanil-Isoglutamina/uso terapêutico , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , Antineoplásicos/efeitos adversos , Neoplasias Ósseas/cirurgia , Progressão da Doença , Humanos , Terapia Neoadjuvante , Osteossarcoma/cirurgia , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/efeitos adversos
20.
Nutrients ; 3(2): 228-44, 2011 02.
Artigo em Inglês | MEDLINE | ID: mdl-22254094

RESUMO

Group A rotaviruses are a major cause of diarrhea in the young of many mammalian species. In rotavirus infected piglets mortality can be as high as 60%. Previous research in this laboratory has identified a porcine intestinal GM(3) ganglioside receptor that is required for sialic acid-dependent rotavirus recognition of host cells. In addition, we previously demonstrated exogenously added GM(3) can competitively inhibit porcine rotavirus binding and infectivity of host cells in vitro. Sialyllactose, the carbohydrate moiety of GM(3), is approximately 3 orders of magnitude less effective than GM(3) at inhibiting rotavirus binding to cells. Furthermore, production of therapeutic quantities of GM(3) ganglioside for use as an oral carbomimetic in swine is cost prohibitive. In an effort to circumvent these problems, a sialyllactose-containing neoglycolipid was synthesized and evaluated for its ability to inhibit rotavirus binding and infectivity of host cells. Sialyllactose was coupled to dipalmitoylphosphatidylethanolamine (PE) by reductive amination and the product (SLPE) purified by HPLC. Characterization of the product showed a single primulin (lipid) and resorcinol (sialic acid) positive band by thin layer chromatography and quantification of phosphate and sialic acid yielded a 1:1 molar ratio. Mass spectroscopy confirmed a molecular weight coinciding with SLPE. Concentration-dependent binding of rotavirus to SLPE was demonstrated using a thin-layer overlay assay. Using concentrations comparable to GM(3), SLPE was also shown to inhibit rotavirus binding to host cells by 80%. Furthermore, SLPE was shown to decrease rotavirus infection of host cells by over 90%. Finally, preliminary results of in vivo animal challenge studies using newborn piglets in their natural environment, demonstrated SLPE afforded complete protection from rotavirus disease. The efficacy of SLPE in inhibiting rotavirus binding and infection in vitro and in vivo, coupled with its relatively low-cost, large-scale production capabilities make SLPE a promising candidate for further exploration as a possible prophylactic or therapeutic nutriceutical for combating rotavirus disease in animals. Most importantly, the results presented here provide proof of concept that the nutriceutical approach of providing natural or synthetic dietary receptor mimetics for protection against gastrointestinal virus infectious disease in all species is plausible.


Assuntos
Antivirais/uso terapêutico , Diarreia/prevenção & controle , Ácido N-Acetilneuramínico/metabolismo , Fosfatidiletanolaminas/uso terapêutico , Receptores de Superfície Celular/metabolismo , Infecções por Rotavirus/prevenção & controle , Rotavirus/patogenicidade , Ácidos Siálicos/uso terapêutico , Animais , Antivirais/síntese química , Antivirais/farmacologia , Ligação Competitiva , Diarreia/virologia , Desenho de Fármacos , Gangliosídeo G(M3)/metabolismo , Mucosa Intestinal/metabolismo , Peso Molecular , Fosfatidiletanolaminas/síntese química , Fosfatidiletanolaminas/farmacologia , Infecções por Rotavirus/virologia , Ácidos Siálicos/síntese química , Ácidos Siálicos/farmacologia , Suínos
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