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2.
J Endocr Soc ; 5(4): bvab019, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33817539

RESUMO

Generalized and partial lipodystrophy are rare and complex diseases with progressive clinical and humanistic burdens stemming from selective absence of subcutaneous adipose tissue, which causes reduced energy storage capacity and a deficiency of adipokines such as leptin. Treatment options were limited before leptin replacement therapy (metreleptin) became available. This retrospective study evaluates both clinical and humanistic consequences of the disease and treatment. Chart data were abstracted from a cohort of metreleptin-treated patients with generalized and partial lipodystrophy (n = 112) treated at the US National Institutes of Health. To quantify the quality-of-life consequences of the lipodystrophy disease attributes recorded in chart data, a discrete choice experiment was completed in 6 countries (US, n = 250; EU, n = 750). Resulting utility decrements were used to estimate the quality-adjusted life-year consequences of changes in lipodystrophy attribute prevalence before and after metreleptin. In addition to metabolic impairment, patients with generalized and partial lipodystrophy experienced a range of lipodystrophy consequences, including liver abnormality (94%), hyperphagia (79%), impaired physical appearance (77%), kidney abnormality (63%), reproductive dysfunction (80% of females of reproductive age), and pancreatitis (39%). Improvement was observed in these attributes following initiation of metreleptin. Quality-adjusted life-year gains associated with 12 months of treatment with metreleptin were estimated at 0.313 for generalized and 0.117 for partial lipodystrophy, reducing the gap in quality of life between untreated lipodystrophy and perfect health by approximately 59% and 31%, respectively. This study demonstrates that metreleptin is associated with meaningful clinical and quality-of-life improvements.

3.
Patient ; 14(5): 673-685, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33840079

RESUMO

BACKGROUND: Lipodystrophy comprises a group of conditions characterized by loss of functional adipose tissue, resulting in severe metabolic complications and a complex range of symptoms. OBJECTIVE: This study sought to gain a holistic understanding of the impact of congenital or non-human immunodeficiency virus acquired lipodystrophies on the quality of life of patients and their caregivers and to capture the impact of lipodystrophy on quality of life using a standard instrument. METHODS: Ten patients with lipodystrophies and five caregivers from the USA and UK were recruited through convenience sampling and interviewed using a semi-structured questionnaire containing open-ended questions about disease symptoms and attributes and numerical rating scales to prompt discussion of symptom prevalence and impact. After the interview, participants filled out the 36-Item Short Form (SF-36) survey instrument. Conventional conceptual content analysis methods were used to analyze the anonymized transcripts. RESULTS: Four concepts were developed: diagnostic journey and symptom management, burden of disease, healthcare resource utilization, and support and advocacy. Participants described lengthy diagnostic journeys and frequent interactions with healthcare systems. Many participants became experts on lipodystrophy through the diagnostic journey and described difficulties accessing effective treatment, even after diagnosis. Both patients and caregivers emphasized the ongoing burden of living with lipodystrophy and the accompanying sense of isolation. Participants turned to disease-specific support groups to cope, engaging in knowledge sharing with other patients and caregivers and developing friendships based on shared experiences. Ten participants completed the SF-36, with a mean (standard deviation) SF-36 score of 0.6 (0.2). CONCLUSIONS: Currently, there are no qualitative studies that describe the experiences of patients with lipodystrophy and their caregivers. While additional research is needed, educational work like this study is a promising first step that could lead to early diagnosis and access to treatment and support.


Assuntos
Cuidadores , Lipodistrofia , Humanos , Cuidados Paliativos , Pesquisa Qualitativa , Qualidade de Vida
4.
JAMA Netw Open ; 3(11): e2025866, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33201235

RESUMO

Importance: With the approval of avapritinib for adults with unresectable or metastatic gastrointestinal stromal tumors (GISTs) harboring a platelet-derived growth factor receptor alpha (PDGFRA) exon 18 variant, including PDGFRA D842V variants, and National Comprehensive Cancer Network guideline recommendations as an option for patients with GIST after third-line treatment, it is important to estimate the potential financial implications of avapritinib on a payer's budget. Objective: To estimate the budget impact associated with the introduction of avapritinib to a formulary for metastatic or unresectable GISTs in patients with a PDGFRA exon 18 variant or after 3 or more previous treatments from the perspective of a US health plan. Design, Setting, and Participants: For this economic evaluation, a 3-year budget impact model was developed in March 2020, incorporating costs for drug acquisition, testing, monitoring, adverse events, and postprogression treatment. The model assumed that avapritinib introduction would be associated with increased PDGFRA testing rates from the current 49% to 69%. The health plan population was assumed to be mixed 69% commercial, 22% Medicare, and 9% Medicaid. Base case assumptions included a GIST incidence rate of 9.6 diagnoses per million people, a metastatic PDGFRA exon 18 mutation rate of 1.9%, and progression rate from first-line to fourth-line treatment of 17%. Exposures: The model compared scenarios with and without avapritinib in a formulary. Main Outcomes and Measures: Annual, total, and per member per month (PMPM) budget impact. Results: In a hypothetical 1-million member plan, fewer than 0.1 new patients with a PDGFRA exon 18 variant per year and 1.2 patients receiving fourth-line therapy per year were eligible for treatment. With avapritinib available, the total increase in costs in year 3 for all eligible adult patients with a PDGFRA exon 18 variant was $46 875, or $0.004 PMPM. For patients undergoing fourth-line treatment, the total increase in costs in year 3 was $69 182, or $0.006 PMPM. The combined total budget impact in year 3 was $115 604, or $0.010 PMPM, including an offset of $3607 in postprogression costs avoided or delayed. The higher rates of molecular testing resulted in a minimal incremental testing cost of $453 in year 3. Conclusions and Relevance: These results suggest that adoption of avapritinib as a treatment option would have a minimal budget impact to a hypothetical US health plan. This would be primarily attributable to the small eligible patient population and cost offsets from reduced or delayed postprogression costs.


Assuntos
Antineoplásicos/economia , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Programas de Assistência Gerenciada/economia , Pirazóis/economia , Pirróis/economia , Triazinas/economia , Antineoplásicos/uso terapêutico , Orçamentos , Análise Custo-Benefício , Formulários Farmacêuticos como Assunto , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/secundário , Humanos , Mesilato de Imatinib/economia , Mesilato de Imatinib/uso terapêutico , Indazóis , Medicaid , Medicare , Técnicas de Diagnóstico Molecular/economia , Compostos de Fenilureia/economia , Compostos de Fenilureia/uso terapêutico , Pirazóis/uso terapêutico , Piridinas/economia , Piridinas/uso terapêutico , Pirimidinas/economia , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Sulfonamidas/economia , Sulfonamidas/uso terapêutico , Sunitinibe/economia , Sunitinibe/uso terapêutico , Falha de Tratamento , Triazinas/uso terapêutico , Estados Unidos
5.
ASAIO J ; 66(8): 862-870, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32740129

RESUMO

There is limited data on the cost-effectiveness of continuous-flow left ventricular assist devices (LVAD) in the United States particularly for the bridge-to-transplant indication. Our objective is to study the cost-effectiveness of a small intrapericardial centrifugal LVAD compared with medical management (MM) and subsequent heart transplantation using the respective clinical trial data. We developed a Markov economic framework. Clinical inputs for the LVAD arm were based on prospective trials employing the HeartWare centrifugal-flow ventricular assist device system. To better assess survival in the MM arm, and in the absence of contemporary trials randomizing patients to LVAD and MM, estimates from the Seattle Heart Failure Model were used. Costs inputs were calculated based on Medicare claim analyses and when appropriate prior published literature. Time horizon was lifetime. Costs and benefits were appropriately discounted at 3% per year. The deterministic cost-effectiveness analyses resulted in $69,768 per Quality Adjusted Life Year and $56,538 per Life Year for the bridge-to-transplant indication and $102,587 per Quality Adjusted Life Year and $87,327 per Life Year for destination therapy. These outcomes signify a substantial improvement compared with prior studies and re-open the discussion around the cost-effectiveness of LVADs.


Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar/economia , Análise Custo-Benefício , Feminino , Humanos , Masculino , Cadeias de Markov , Medicare , Estudos Prospectivos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Estados Unidos
7.
J Nanosci Nanotechnol ; 20(6): 3404-3414, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748033

RESUMO

Andrographolide, a diterpenoid compound found in the aerial parts of Andrographis paniculata (a well known anti snake venom plant) was conjugated with gold nanoparticle (andrographolide-AuNPs) and its efficacy against Daboia russellii russellii venom (DRRV) induced local damage, organ toxicity and inflammatory response was evaluated in animal models. Ethical clearance was obtained before animal experiments. Andrographolide-AuNPs was formed by adsorption method. Physico-chemical characterization of particle was done by dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Swiss albino male mice were divided into 5 groups: Gr. 1-Sham control, Gr. 2-DRRV control, Gr. 3-anti snake venom serum treated, Gr. 4-andrographolide treated and Gr. 4-andrographolide-AuNPs treated. 1/5th minimum lethal dose of DRRV (10 µg/s.c./20 g mice) was induced in animals of group 2, 3, 4 and 5 animals, followed by treatment with anti snake venom serum (2 mg/20 g mice, i.v.) andrographolide (50 µg/20g mice, i.p.) and andrographolide-AuNPs (50 µg/20 g mice, i.v.) in group 3, 4 and 5 animals, respectively. Blood was collected after 18 h, serum was prepared and organ toxicity markers (transaminases, phosphatases, lactate dehydrogenase, creatine phosphate, urea, creatinine, Ca2+, phosphorous), inflammatory markers (interleukin 1ß, 6, 17a, 10, tumor necrosis factor α) and local damage testings (defibrination, edema, hemorrhage) were assessed. Values were expressed as mean ± SEM (n = 4), one way analysis of variance was done, P < 0.05 was considered as statistically significant. Formed andrographolide-AuNPs were pink in color with hydrodynamic diameter 30-50 nm, polydispersity index 0.412 and zeta potential -16.21 mV. XRD data confirmed the presence of crystalline gold in andrographolide-AuNPs. TEM (20-50 nm) and FE-SEM (20-25 nm) indicated the presence of nearly spherical particle. DRRV envenomation followed by treatment with andrographolide-AuNPs provided protection against venom induced edema, hemorrhage, defibrination, organ toxicity and inflammation in animal model. Venom neutralization by andrographolide-AuNPs was > andrographolide, which confirmed the increased efficacy of andrographolide after gold nanoparticle conjugation, may be due to anti-oxidant/anti-inflammatory activity of andrographolide, showing increased efficacy after gold nanoparticle tagging. Thus, andrographolide-AuNPs may serve as a supportive therapy in snakebite (against venom induced local damage, organ toxicity and inflammatory response) subject to further detail studies.


Assuntos
Diterpenos , Nanopartículas Metálicas , Animais , Diterpenos/toxicidade , Ouro , Nanopartículas Metálicas/toxicidade , Camundongos , Modelos Animais , Extratos Vegetais
8.
Toxicon ; 131: 48-53, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28315357

RESUMO

Kraits belong to Elapideae and are widely distributed in East and South-East Asian countries. Krait venom possesses neurotoxins, membrane toxins, cardiotoxins, three finger toxins, metalloproteinases, cholinesterases, L-amino acid oxidases and serine proteases. The therapeutic potential of krait venom in pathophysiological conditions such as microbial and parasitic infections, cancer, arthritis, inflammation and blood coagulation disorder is discussed in this review. More intensive new research ventures are required to establish the therapeutic potential of krait venom in complex and emerging diseases.


Assuntos
Bungarus , Venenos Elapídicos/farmacologia , Animais , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Anticoagulantes/farmacologia , Antineoplásicos/farmacologia , Antiprotozoários/farmacologia , Humanos
9.
J Nanosci Nanotechnol ; 16(1): 92-116, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27398436

RESUMO

Nanoparticles owing to their unique physico-chemical properties have found its application in various biological processes, including metabolic pathways taking place within the body. This review tried to focus the involvement of nanoparticles in metabolic pathways and its influence in the energy metabolism, a fundamental criteria for the survival and physiological activity of living beings. The human body utilizes energy derived from food resources through a series of biochemical reactions involving several enzymes, co-factors (metals, non-metals, vitamins etc.) through the metabolic pathways (glycolysis, tri carboxylic acid cycle, oxidative phosphorylation, electron transport chain, etc.) in cellular system. Energy metabolism is also involved in the immune networking of the body for self defence and against pathophysiology. The immune system comprises of different cells and tissues, bioactive molecules for self defence and to fight against diseases. In the recent times, it has been reported through in vivo and in vitro studies that nanoparticles have direct influence on body's immune functions, and can modulate immunity by either suppressing or enhancing it. A comprehensive overview of nanoparticles and its involvement in immune function of the body in normal and pathophysiological conditions has been discussed. Considering these perspectives on nanoparticle interaction another important area which has been highlighted is the biosafety issues which are necessary before therapeutic applications. It is expected that development of physiologically compatible nanoparticles controlling energy metabolic processes, immune functions may show new dimension in the pathophysiology linked with energy and immunity.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Tolerância Imunológica/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Nanopartículas/efeitos adversos , Animais , Humanos
10.
Toxicon ; 118: 43-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27108237

RESUMO

A heat stable protein BF-F47 was purified from the crude venom of Bungarus fasciatus by CM cellulose ion exchange chromatography and HPLC. Osteoarthritis (OA) was developed in male albino Wistar rats by collagenase injection. BF-F47 treatment significantly restored urinary hydroxyproline and glucosamine in OA rats. Serum acid phosphatase, alkaline phosphatase, creatinine and serum molecular markers TNF-α, IL-1ß, IL-17, cytokine induced neutrophil chemoattractant-1, matrix metalloproteinase-1, cathepsin-K, osteocalcin and PGE2 were also significantly altered. BF-F47 showed partial restoration of osteoarthritis joints. Thus, BF-F47 induced anti-osteoarthritic activity in Wistar rats acted through molecular markers of arthritis and inflammation.


Assuntos
Produtos Biológicos/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Bungarus , Modelos Animais de Doenças , Venenos Elapídicos/química , Venenos Elapídicos/uso terapêutico , Osteoartrite/tratamento farmacológico , Proteínas de Répteis/uso terapêutico , Animais , Produtos Biológicos/administração & dosagem , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores/urina , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/química , Conservadores da Densidade Óssea/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Dinoprostona/sangue , Venenos Elapídicos/administração & dosagem , Venenos Elapídicos/isolamento & purificação , Glucosamina/urina , Hidroxiprolina/urina , Índia , Mediadores da Inflamação/sangue , Injeções Intraperitoneais , Articulações/efeitos dos fármacos , Articulações/imunologia , Articulações/metabolismo , Masculino , Osteoartrite/imunologia , Osteoartrite/metabolismo , Osteocalcina/sangue , Estabilidade Proteica , Ratos Wistar , Proteínas de Répteis/administração & dosagem , Proteínas de Répteis/química , Proteínas de Répteis/isolamento & purificação
11.
Toxicon ; 90: 106-10, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25026566

RESUMO

The anti arthritic and anti inflammatory activity of NN-32, a cytotoxic protein from Indian spectacle cobra snake (Naja naja) venom has been studied in Freund's complete adjuvant (FCA) induced arthritis and carrageenan induced anti inflammatory model. NN-32 treatment showed significant decrease in physical and urinary parameters, serum enzymes, serum cytokines levels as compared to arthritic control group of rats. NN-32 treatment recovered carrageenan induced inflammation as compared to control group of rats. The findings showed that the cytotoxic protein NN-32 shares anti arthritic and anti inflammatory activity and thus NN-32 may target complex pathophysiological processes like cancer- arthritis-inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite/tratamento farmacológico , Venenos Elapídicos/química , Proteínas/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Elapidae , Masculino , Proteínas/uso terapêutico , Ratos
12.
J Nanosci Nanotechnol ; 14(1): 990-1006, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24730316

RESUMO

Nanotechnology has been setting benchmarks for the last two decades, but the origins of this technology reach back to ancient history. Today, nanoparticles of both metallic and non-metallic origin are under research and development for applications in various fields of biology/therapeutics. Physiologically important metals are of concern because they are compatible with the human system in terms of absorption, assimilation, excretion, and side effects. There are several physiologically inorganic metals that are present in the human body with a wide range of biological activities. Some of these metals are magnesium, chromium, manganese, iron, cobalt, copper, zinc, selenium and molybdenum. These metals are synthesized in the form of nanoparticles by different physical and chemical methods. Physiologically important nanoparticles are currently under investigation for their bio-medical applications as well as for therapeutics. Along with the applicative aspects of nanoparticles, another domain that is of great concern is the risk assessment of these nanoparticles to avoid unnecessary hazards. It has been seen that these nanoparticles have been shown to possess toxicity in biological systems. Conventional physical and chemical methods of metal nanoparticle synthesis may be one possible reason for nanoparticle toxicity that can be overcome by synthesis of nanoparticles from biological sources. This review is an attempt to establish metal nanoparticles of physiological importance to be the best candidates for future nanotechnological tools and medicines, owing to the acceptability and safety in the human body. This can only be successful if these particles are synthesized with a better biocompatibility and low or no toxicity.


Assuntos
Materiais Biocompatíveis/toxicidade , Medicina Baseada em Evidências , Nanopartículas Metálicas/toxicidade , Animais , Humanos
14.
Toxicon ; 74: 138-50, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23981271

RESUMO

BF-CT1, a 13 kDa protein isolated from Bungarus fasciatus snake venom through CM cellulose ion exchange chromatography at 0.02 M NaCl salt gradient showed cytotoxicity in in vitro and in vivo experimental models. In in vivo Ehrlich ascites carcinoma (EAC) induced BALB/c mice model, BF-CT1 treatment reduced EAC cell count significantly through apoptotic cell death pathway as evidenced by FACS analysis, increased caspase 3, 9 activity and altered pro, antiapoptotic protein expression. BF-CT1 treatment caused cell shrinkage, chromatin condensation and induced apoptosis through increased caspase 3, caspase 9 activity, PARP cleavage and down regulation of heat shock proteins in U937 leukemic cell line. Cytosolic cytochrome C production was increased after BF-CT1 treatment upon U937 cell line. BF-CT1 treated U937 cell showed cell cycle arrest at sub G1 phase through cyclin D and CDK down regulation with up regulation of p15 and p16. It also down regulated PI3K/AKT pathway and MAPkinase pathway and promoted apoptosis and regulated cell proliferation in U937 cells. BF-CT1 prevented angiogenesis in in vitro U937 cell line through decreased VEGF and TGF-ß1 production.


Assuntos
Apoptose/efeitos dos fármacos , Bungarus , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Répteis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Venenos de Serpentes/farmacologia , Indutores da Angiogênese/farmacologia , Animais , Anexina A5/farmacologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D/genética , Ciclina D/metabolismo , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Répteis/isolamento & purificação , Venenos de Serpentes/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fator de Crescimento Transformador beta1/metabolismo , Células U937 , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Exp Parasitol ; 135(1): 126-33, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23830987

RESUMO

Leishmaniasis threatens more than 350 million people worldwide specially in tropical and subtropical region. Antileishmanial drugs that are currently available have various limitations. The search of new drugs from natural products (plants, animals) possessing antileishmanial activity is ventured throughout the world. The present study deals with the antileishmanial activity of Bungarus caeruleus snake venom (BCV) on in vitro promastigotes and amastigotes of Leishmania donovani parasite and leishmania infected BALB/c mice. The effect of BCV on peritoneal macrophage, release of cytokines from the activated macrophages, production of nitric oxide, reactive oxygen species and cytokines were studied in vivo and in vitro. IC50 value of BCV on L. donovani promastigote was 14.5 µg/ml and intracellular amastigote was 11.2 µg/ml. It activated peritoneal macrophages, significantly increased cytokines and interleukin production. BCV (20 µg/kg and 40 µg/kg body weight of mice) decreased parasite count by 54.9% and 74.2% in spleen and 41.4% and 60.4% in liver of infected BALB/c mice. BCV treatment significantly increased production of TNF-α, IFN-γ, ROS, NO in infected mice. Histological studies showed decreased granuloma formation in treated liver as compared with control. Liver and spleen structure was partially restored due to BCV treatment in infected mice. The present study revealed that BCV possessed antileishmanial activity against L. donovani parasite in vivo and in vitro and this activity was partly mediated through immunomodulatory activity involving macrophages.


Assuntos
Antiprotozoários/farmacologia , Bungarotoxinas/farmacologia , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Animais , Gluconato de Antimônio e Sódio/farmacologia , Gluconato de Antimônio e Sódio/uso terapêutico , Antiprotozoários/uso terapêutico , Bungarotoxinas/uso terapêutico , Bungarus , Cricetinae , Relação Dose-Resposta a Droga , Feminino , Concentração Inibidora 50 , Interferon gama/metabolismo , Leishmaniose Visceral/imunologia , Fígado/parasitologia , Fígado/patologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/parasitologia , Masculino , Mesocricetus , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Baço/parasitologia , Baço/patologia , Fator de Necrose Tumoral alfa/metabolismo
16.
Life Sci ; 93(7): 271-6, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23850515

RESUMO

AIMS: The aim of this study was to assess the autophagy inducing ability of the scorpion venom toxin Bengalin in human leukemic U937 cells. The same toxin was previously shown to induce apoptosis in human leukemic cells. MAIN METHODS: Bengalin was purified from Indian black scorpion (Heterometrus bengalensis) venom by ion exchange chromatography and HPLC. In human leukemic U937 cells, Bengalin associated MAPK (mitogen activated protein kinase) pathway was determined by western blotting. Downstream to MAPK, the Bengalin induced apoptosis-mediator caspase-3 was blocked by chemical inhibitor and reconfirmed by siRNA mediated gene knockdown. Subsequent to caspase-3 blocking, the autophagic response was evaluated by quantification of acidic vesicle organelles formation and modulations of Atg's, Beclin-1, LC3-1 and LC3-II expression by western blotting. KEY FINDINGS: In U937 cells, Bengalin increased ERK1/2 expression to bring about cell death. However in subsequent caspase-3 blocked conditions, Bengalin downregulated p-Akt, p-mTOR and decreased apoptosis. It had also increased the percentage of acidic vesicle organelles positive cells. Bengalin could induce autophagic response by augmenting Beclin-1, Atg12, Atg7, Atg5 and Atg3 in U937 cells. Moreover a time dependant reciprocal relation was observed between LC3-I and LC3-II expression upon Bengalin treatment. The decrease in LC3-II was inhibited in the presence of lysozomal enzyme blockers thereby suggesting lysosome involvement in the autophagic response. SIGNIFICANCE: We have for the first time demonstrated that scorpion venom-component could induce an alternate cell death pathway other than apoptosis in the form of autophagy in human leukemic U937 cells.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Venenos de Escorpião/farmacologia , Western Blotting , Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Organelas/efeitos dos fármacos , Organelas/metabolismo , RNA Interferente Pequeno/metabolismo , Venenos de Escorpião/química , Venenos de Escorpião/isolamento & purificação , Sais de Tetrazólio , Tiazóis , Células U937
17.
Toxicon ; 65: 1-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23337397

RESUMO

A cytotoxin NN-32 (6.7 kDa) from Indian cobra (Naja naja) venom inhibited human leukemic U937 cell growth as observed by Trypan blue dye exclusion method and cytotoxicity was confirmed by MTT assay. NN-32 induced apoptosis of U937 cell and cell cycle arrest of sub-G1 phase were revealed by FACS analysis. Increased Bax/Bcl-2 ratio, increased caspase 3 and 9 activities, cleaved PARP, decreased VEGF, MMP-2 and MMP-9 activities were observed after NN-32 treatment of U937 cell. Antileukemic activity of NN-32 on U937 cell may be due to activation of apoptosis, arresting cell cycle and antiangiogenesis activities.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteínas Cardiotóxicas de Elapídeos/farmacologia , Citostáticos/farmacologia , Venenos Elapídicos/química , Animais , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas Cardiotóxicas de Elapídeos/isolamento & purificação , Citostáticos/isolamento & purificação , Elapidae , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Células U937 , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
J Venom Res ; 3: 15-21, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23236583

RESUMO

Nano-medical approaches to develop drugs have attracted much attention in different arenas to design nanoparticle conjugates for better efficacy of the potential bio-molecules. A group of promising candidates of this category would be venom-toxins of animal origin of potential medicinal value. Traditional systems of medicine as well as folklores mention the use of venom-toxins for the treatment of various diseases. Research has led to scientific validation of medicinal applications of venoms-toxins and many active constituents derived from venoms-toxins are already in clinical use or under clinical trial. Nanomedicine is an emerging field of medicine where nanotechnology is used to develop molecules of nano-scale dimension, so that these molecules can be taken up by the cells more easily and have better efficacy, as compared to large molecules that may tend to get eliminated. This review will focus on some of the potential venoms and toxins along with nanoparticle conjugated venom-toxins of snakes, amphibians, scorpions and bees, etc., for possible therapeutic clues against emerging diseases.

19.
Indian J Med Res ; 136(1): 40-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22885262

RESUMO

BACKGROUND & OBJECTIVES: Phospholipase A2 (PLA2 ) is one of the major constituents of krait venom associated with several pathophysiological actions like myotoxicity, cardiotoxicity, neurotoxicity, etc. As there was no specific antiserum available against Bungarus fasciatus venom, this study was done with synthetic herbal compounds, anti PLA2 rabbit antiserum and commercial polyvalent snake venom antiserum to neutralize the PLA2 induced toxicities in experimental models. METHODS: B. fasciatus venom phospholipase A2 fraction 38 (BF-38) was isolated by ion exchange chromatography, molecular weight was determined by mass spectrometry and its N terminal amino acid sequence was identified. Monospecific rabbit antiserum was raised against the PLA2 in presence of Freund complete adjuvant. The neutralization of PLA2 induced toxicities was done in in vitro and in in vivo models using synthetic herbal compounds, anti PLA2 rabbit antiserum and commercial polyvalent snake venom antiserum. RESULTS: A toxic PLA2 (BF-38) was purified from the B. fasciatus venom by CM-cellulose and HPLC, of 13.17 kDa and a minor band of 7.3 kDa using ESI-MS. The 13.17 kDa PLA2 sequence was NLYQFKNMIQC. The 7.3 kDa toxin sequence was RKCLTKYSQDNES and was found to be <10 per cent w/w. Anti PLA2 rabbit antiserum produced faint precipitant band in immunogel diffusion and showed low titre value. The commercial polyvalent snake venom antiserum, anti PLA2 rabbit antiserum and the synthetic herbal compounds neutralized the PLA2 induced toxicities at different intensities. INTERPRETATION & CONCLUSIONS: Our results suggested that synthetic herbal compound (BA) along with antiserum might provide effective protection against PLA2 induced toxicities of B. fasciatus venom.


Assuntos
Bungarotoxinas/metabolismo , Bungarus , Soros Imunes/farmacologia , Inibidores de Fosfolipase A2 , Fosfolipases A2/metabolismo , Extratos Vegetais/farmacologia , Sequência de Aminoácidos , Animais , Benzoatos/farmacologia , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Éteres de Hidroxibenzoatos/farmacologia , Espectrometria de Massas , Dados de Sequência Molecular , Coelhos , Ácido Salicílico/farmacologia , Testes de Toxicidade
20.
FEBS J ; 279(16): 2876-91, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22715906

RESUMO

Tea polyphenols have potent biological activities against human cancer cells. A major causative factor in malignancies is disregulation of cell-cycle kinetics. In this study, we observed that black tea polyphenols, theaflavins (TF) and thearubigins (TR) induced cell-cycle arrest at the G(0) /G(1) phase in human leukemic U937 and K562 cells. Our objective was to understand the underlying molecular mechanism of cell-cycle inhibition by TF and TR. During elucidation, we observed that both TF and TR treatment augmented expression of p19, p21 and p27, while ablating cylcin-dependent kinase (CDK)2, CDK4, CDK6 and cyclin D1 levels. Our experimental results further determined that Akt signaling suppression by TF and TR played a major role in this process. Moreover, suppression of glycogen synthase kinase-3ß, ß-catenin and amplification of forkhead transcription factor 1 (FOXO1) expression were associated with regulation of certain key components of the cell-cycle machinery. In addition, depletion of heat shock protein (Hsp) 90 by TF and TR also had a pivotal role in cell-cycle arrest. More specifically, inhibition of Akt signaling by TF and TR correlated with the depletion of its downstream targets like Wnt/ß-catenin signaling, cyclin D1 and increase of FOXO1, p27 levels. Inhibition of upstream Hsp90 by TF and TR consequently attenuated Akt signaling and reduced the level of CDK2. These results suggest possible mechanisms for the chemopreventive effect of TF and TR on human leukemic cells. To our knowledge, this is the first report of such a detailed molecular mechanism for TF and the less-investigated polyphenol TR-mediated cell-cycle inhibition in human leukemic U937 and K562 cells.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Polifenóis/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Biflavonoides/farmacologia , Camellia sinensis/química , Catequina/análogos & derivados , Catequina/farmacologia , Quinases Ciclina-Dependentes/antagonistas & inibidores , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/fisiologia , Fase G1/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/fisiologia , Humanos , Células K562 , Fenóis/farmacologia , Células U937 , Proteínas Wnt/fisiologia , beta Catenina/fisiologia
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