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1.
ACS Chem Neurosci ; 8(12): 2759-2765, 2017 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-28880525

RESUMO

Mitochondrial dysfunction is thought to play a significant role in neurodegeneration observed in Parkinson's disease (PD), yet the mechanisms underlying this pathology remain unclear. Here, we demonstrate that loss of mitoNEET (CISD1), an iron-sulfur containing protein that regulates mitochondrial bioenergetics, results in mitochondrial dysfunction and loss of striatal dopamine and tyrosine hydroxylase. Mitochondria isolated from mice lacking mitoNEET were dysfunctional as revealed by elevated reactive oxygen species (ROS) and reduced capacity to produce ATP. Gait analysis revealed a shortened stride length and decreased rotarod performance in knockout mice, consistent with the loss of striatal dopamine. Together, these data suggest that mitoNEET KO mice exhibit many of the characteristics of early neurodegeneration in PD and may provide a novel drug discovery platform to evaluate compounds for enhancing mitochondrial function in neurodegenerative disorders.


Assuntos
Corpo Estriado/metabolismo , Corpo Estriado/patologia , Modelos Animais de Doenças , Proteínas de Ligação ao Ferro/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Doença de Parkinson/metabolismo , Animais , Proteínas de Ligação ao Ferro/genética , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doença de Parkinson/patologia
2.
Bioorg Med Chem Lett ; 27(2): 303-308, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27913180

RESUMO

Elevated triglycerides (TG) contribute towards increased risk for cardiovascular disease. Lipoprotein lipase (LPL) is an enzyme that is responsible for the metabolism of core triglycerides of very-low density lipoproteins (VLDL) and chylomicrons in the vasculature. In this study, we explored the structure-activity relationships of our lead compound (C10d) that we have previously identified as an LPL agonist. We found that the cyclopropyl moiety of C10d is not absolutely necessary for LPL activity. Several substitutions were found to result in loss of LPL activity. The compound C10d was also tested in vivo for its lipid lowering activity. Mice were fed a high-fat diet (HFD) for four months, and treated for one week at 10mg/kg. At this dose, C10d exhibited in vivo biological activity as indicated by lower TG and cholesterol levels as well as reduced body fat content as determined by ECHO-MRI. Furthermore, C10d also reduced the HFD induced fat accumulation in the liver. Our study has provided insights into the structural and functional characteristics of this novel LPL activator.


Assuntos
Benzenoacetamidas/farmacologia , Imidazóis/farmacologia , Lipase Lipoproteica/metabolismo , Animais , Benzenoacetamidas/síntese química , Benzenoacetamidas/química , Relação Dose-Resposta a Droga , Imidazóis/síntese química , Imidazóis/química , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
3.
Drug Discov Today ; 22(2): 352-365, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27771332

RESUMO

Although statins and other pharmacological approaches have improved the management of lipid abnormalities, there exists a need for newer treatment modalities especially for the management of hypertriglyceridemia. Lipoprotein lipase (LPL), by promoting hydrolytic cleavage of the triglyceride core of lipoproteins, is a crucial node in the management of plasma lipid levels. Although LPL expression and activity modulation is observed as a pleiotropic action of some the commonly used lipid lowering drugs, the deliberate development of drugs targeting LPL has not occurred yet. In this review, we present the biology of LPL, highlight the LPL modulation property of currently used drugs and review the novel emerging approaches to target LPL.


Assuntos
Doenças Cardiovasculares/enzimologia , Lipase Lipoproteica/metabolismo , Doenças Metabólicas/enzimologia , Animais , Doenças Cardiovasculares/tratamento farmacológico , Humanos , Lipase Lipoproteica/química , Doenças Metabólicas/tratamento farmacológico
4.
Bioorg Med Chem Lett ; 26(21): 5350-5353, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27687671

RESUMO

MitoNEET (CISD1) is a 2Fe-2S iron-sulfur cluster protein belonging to the zinc-finger protein family. Recently mitoNEET has been shown to be a major role player in the mitochondrial function associated with metabolic type diseases such as obesity and cancers. The anti-diabetic drug pioglitazone and rosiglitazone were the first identified ligands to mitoNEET. Since little is known about structural requirements for ligand binding to mitoNEET, we screened a small set of compounds to gain insight into these requirements. We found that the thiazolidinedione (TZD) warhead as seen in rosiglitazone was not an absolutely necessity for binding to mitoNEET. These results will aid in the development of novel compounds that can be used to treat mitochondrial dysfunction seen in several diseases.


Assuntos
Proteínas Mitocondriais/metabolismo , Bibliotecas de Moléculas Pequenas , Hipoglicemiantes/química , Hipoglicemiantes/metabolismo , Ligantes , Ligação Proteica , Tiazolidinedionas/química , Tiazolidinedionas/metabolismo
5.
Front Pharmacol ; 6: 292, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26696891

RESUMO

Nitric oxide (NO) plays a critical role in the motoric and glutamate releasing action of N-methyl-D-aspartate (NMDA)-antagonist stimulants. Earlier studies utilized neuronal nitric oxide synthase inhibitors (nNOS) for studying the neurobehavioral effects of non-competitive NMDA-antagonist stimulants such as dizocilpine (MK-801) and phencyclidine (PCP). This study explores the role of the inducible nitric oxide synthase inhibitors (iNOS) aminoguanidine (AG) and (-)-epigallocatechin-3-gallate (EGCG) in NMDA-antagonist induced motoric behavior and prefrontal cortical glutamate efflux. Adult male rats were administered a dose range of AG, EGCG, or vehicle prior to receiving NMDA antagonists MK-801, PCP, or a conventional psychostimulant (cocaine) and tested for motoric behavior in an open arena. Glutamate in the medial prefrontal cortex (mPFC) was measured using in vivo microdialysis after a combination of AG or EGCG prior to MK-801. Acute administration of AG or EGCG dose-dependently attenuated the locomotor and ataxic properties of MK-801 and PCP. Both AG and EGCG were unable to block the motoric effects of cocaine, indicating the acute pharmacologic action of AG and EGCG is specific to NMDA antagonism and not generalizable to all stimulant class drugs. AG and EGCG normalized MK-801-stimulated mPFC glutamate efflux. These data demonstrate that AG and EGCG attenuates NMDA antagonist-stimulated motoric behavior and cortical glutamate efflux. Our results suggest that EGCG-like polyphenol nutraceuticals (contained in "green tea" and chocolate) may be clinically useful in protecting against the adverse behavioral dissociative and cortical glutamate stimulating effects of NMDA antagonists. Medications that interfere with NMDA antagonists such as MK-801 and PCP have been proposed as treatments for schizophrenia.

6.
Am J Pharm Educ ; 79(6): 82, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26430269

RESUMO

Objective. To develop, implement, and modify a required, second-year pharmacy course that provides an understanding of the scientific, therapeutic, and clinical principles, as well as the evidence-based medicine underlying the use of natural products. Design. A 28-hour, multi-faculty course was developed and offered in 2008. The course was modified over the years to enhance students' practice skills in the use of natural products. A course evaluation and survey were administered to assess the students' opinions. Assessment. Students performed well in the course and provided favorable evaluations, especially for the latest offering. Students reported significantly improved skills in providing advice to patients regarding the use of natural products. Conclusion. The course increased the students' knowledge and application of information and counseling skills regarding natural products.


Assuntos
Produtos Biológicos , Competência Clínica , Currículo/tendências , Suplementos Nutricionais , Educação em Farmácia/tendências , Estudantes de Farmácia , Produtos Biológicos/uso terapêutico , Educação em Farmácia/métodos , Avaliação Educacional/métodos , Humanos
7.
Expert Rev Neurother ; 15(1): 3-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25481975

RESUMO

Alzheimer's disease (AD) and its related dementia has shown an alarming rise in the global population. Although considerable efforts have been made to develop effective therapeutic agents for AD therapy, drug development has not met significant clinical success. Current pharmacotherapy of AD is limited to cholinesterase inhibitors and the N-methyl-D-aspartate antagonist memantine. Considerable research is underway to develop newer agents for the management of AD. Since amyloid-ß (Aß) has been implicated in AD pathogenesis, the use of ß secretase inhibitors as well as immunotherapy against Aß has been investigated. A considerable effort has been spent investigating the therapeutic potential of antioxidants and anti-inflammatory agents, several of natural products and dietary origin, in AD treatment. Numerous drug targets have also been investigated for AD treatment and a modest drug pipeline is available. Despite these efforts, drug development for AD has proved extremely difficult and most clinical trials have afforded disappointing results.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Tratamento Farmacológico/métodos , Tratamento Farmacológico/tendências , Humanos
8.
Artigo em Inglês | MEDLINE | ID: mdl-23606879

RESUMO

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide, and chemoprevention represents a viable approach in lowering the mortality of this disease. Pomegranate fruit, an abundant source of anti-inflammatory phytochemicals, is gaining tremendous attention for its wide-spectrum health benefits. We previously reported that a characterized pomegranate emulsion (PE) prevents diethylnitrosamine (DENA)-induced rat hepatocarcinogenesis though inhibition of nuclear factor-kappaB (NF- κ B). Since NF- κ B concurrently induces Wnt/ ß -catenin signaling implicated in cell proliferation, cell survival, and apoptosis evasion, we examined antiproliferative, apoptosis-inducing and Wnt/ ß -catenin signaling-modulatory mechanisms of PE during DENA rat hepatocarcinogenesis. PE (1 or 10 g/kg) was administered 4 weeks before and 18 weeks following DENA exposure. There was a significant increase in hepatic proliferation (proliferating cell nuclear antigen) and alteration in cell cycle progression (cyclin D1) due to DENA treatment, and PE dose dependently reversed these effects. PE substantially induced apoptosis by upregulating proapoptotic protein Bax and downregulating antiapoptotic protein Bcl-2. PE dose dependently reduced hepatic ß -catenin and augmented glycogen synthase kinase-3 ß expression. Our study provides evidence that pomegranate phytochemicals exert chemoprevention of hepatic cancer through antiproliferative and proapoptotic mechanisms by modulating Wnt/ ß -catenin signaling. PE, thus, targets two interconnected molecular circuits (canonical NF- κ B and Wnt/ ß -catenin pathways) to exert chemoprevention of HCC.

9.
Nutr Cancer ; 65(3): 329-44, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23530632

RESUMO

The prophylactic and therapeutic properties of tea have been attributed to green tea catechins and black tea theaflavins besides several other polyphenolic compounds. Tea polyphenols possess potent antioxidant and antiinflammatory properties and modulate several signaling pathways. These biochemical facets of tea polyphenols are responsible for its anticancer properties. Several lethal cancers, such as liver cancer, develop within a background of oxidative stress and inflammation. Liver cancer, also known as hepatocellular carcinoma (HCC), has been shown to occur throughout the world including Asia, Africa, Western Europe, and the United States. Phytochemicals, such as tea polyphenols, provide an effective and promising alternative for the chemoprevention and treatment of HCC. In this article, we systematically review, for the first time, the effects of tea polyphenols in the preclinical in vitro and in vivo HCC models. The review also examines, in critical detail, the biochemical mechanisms involved in the chemopreventive and antineoplastic effects of tea polyphenols in hepatic cancer. Finally, we highlight the role of synergy, bioavailability and pharmacokinetics of tea polyphenols, current status of clinical trials, discuss future directions, and comment on the future challenges involved in the effective use of tea polyphenols for the prevention and management of liver cancer.


Assuntos
Anticarcinógenos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/prevenção & controle , Polifenóis/administração & dosagem , Chá/química , Animais , Anti-Inflamatórios , Antioxidantes , Disponibilidade Biológica , Catequina/administração & dosagem , Catequina/análogos & derivados , Quimioprevenção , Modelos Animais de Doenças , Humanos , Camundongos , Polifenóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Int J Cancer ; 133(5): 1054-63, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23404339

RESUMO

Breast cancer represents one of the most frequently diagnosed cancers and predominant causes of death in women worldwide. The value of preventive therapy to limit the devastating impact of breast cancer is well established. Various plant triterpenoids and their synthetic analogs have shown significant promise as potent chemopreventive agents in breast cancer. The current study was initiated to investigate mechanism-based chemopreventive potential of a novel synthetic oleanane triterpenoid (methyl-25-hydroxy-3-oxoolean-12-en-28-oate, AMR-Me) against 7,12-dimethylbenz(a)anthracene (DMBA)-initiated rat mammary carcinogenesis, an experimental rodent tumor model that closely resembles human mammary cancer. Rats were orally administered with AMR-Me (0.8, 1.2 and 1.6 mg/kg) three times per week for 18 weeks. Following two weeks of AMR-Me treatment, mammary carcinogenesis was initiated by oral administration of DMBA (50 mg/kg body weight). At the end of the study (16 weeks following DMBA exposure), AMR-Me exhibited a striking inhibition of DMBA-induced mammary tumor incidence, total tumor burden, average tumor weight and reversed histopathological alterations without toxicity. AMR-Me dose-dependently suppressed abnormal cell proliferation, induced apoptosis, up-regulated pro-apoptotic protein Bax and down-regulated antiapoptotic protein Bcl-2 in mammary tumors. AMR-Me upregulated the transcriptional levels of Bax, Bad, caspase-3, caspase-7 and poly(ADP-ribose) polymerase and down-regulated Bcl-2. These results clearly demonstrate for the first time that novel triterpenoid AMR-Me exerts chemopreventive efficacy in the classical DMBA model of breast cancer by suppressing abnormal cell proliferation and inducing apoptosis mediated through mitochondrial pro-apoptotic mechanisms. AMR-Me could be developed as a chemopreventive drug to reduce the risk of human breast cancer that remains a devastating disease.


Assuntos
Anticarcinógenos/farmacologia , Neoplasias Mamárias Experimentais/prevenção & controle , Ácido Oleanólico/análogos & derivados , 9,10-Dimetil-1,2-benzantraceno , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Ácido Oleanólico/farmacologia , Ratos , Ratos Sprague-Dawley
11.
Mol Carcinog ; 52(4): 304-17, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22213170

RESUMO

Black currant fruits containing high amounts of anthocyanins are known to possess potent antioxidant and anti-inflammatory properties. We have previously reported that anthocyanin-rich black currant skin extract (BCSE) inhibits diethylnitrosamine (DENA)-initiated hepatocarcinogenesis in rats although the underlying mechanisms are not fully understood. Our present study investigates the anti-inflammatory mechanisms of BCSE during DENA rat liver carcinogenesis. Dietary BCSE (100 or 500 mg/kg) treatment for 22 wk afforded a striking inhibition of DENA-induced hepatic gamma-glutamyl transpeptidase-positive preneoplastic foci in a dose-responsive fashion. There was a significant increase in hepatic expression of heat shock proteins (HSP70 and HSP90), cyclooxygenase-2, and nuclear factor-κB (NF-κB) in DENA-exposed rat livers. Dietary BCSE dose-dependently abrogated all these elevated inflammatory markers. The possible cardiotoxicity of BCSE was assessed by monitoring cardiac functions using transthoracic echocardiography. BCSE-mediated anti-inflammatory effects during rat liver carcinogenesis have been achieved without any cardiotoxicity. Our results provide convincing evidence, for the very first time, that suppression of the inflammatory cascade through modulation of the NF-κB signaling pathway could be implicated, at least in part, in the chemopreventive effects of black currant bioactive phytoconstituents against experimental hepatocarcinogenesis. These results coupled with an excellent safety profile of BCSE support the development of black currant phytochemicals for the chemoprevention of inflammation-driven hepatocellular cancer.


Assuntos
Antocianinas/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Inflamação/prevenção & controle , Neoplasias Hepáticas Experimentais/prevenção & controle , Fígado/efeitos dos fármacos , Ribes/química , Alquilantes , Animais , Antocianinas/química , Antocianinas/farmacologia , Anticarcinógenos/química , Anticarcinógenos/farmacologia , Anticarcinógenos/uso terapêutico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/imunologia , Dietilnitrosamina , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/imunologia , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/imunologia , Inflamação/genética , Inflamação/imunologia , Fígado/imunologia , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/imunologia , Masculino , NF-kappa B/genética , NF-kappa B/imunologia , Ratos , Ratos Sprague-Dawley
12.
J Nutr Biochem ; 24(1): 178-87, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22841394

RESUMO

Liver cancer, predominantly hepatocellular carcinoma (HCC), represents a complex and fatal malignancy driven primarily by oxidative stress and inflammation. Due to dismal prognosis and limited therapeutic intervention, chemoprevention has emerged as a viable approach to reduce the morbidity and mortality of HCC. Pomegranate fruit is a rich source of phytochemicals endowed with potent antioxidant and anti-inflammatory properties. We previously reported that pomegranate phytochemicals inhibit diethylnitrosamine (DENA)-initiated hepatocarcinogenesis in rats though nuclear factor E2-related factor 2 (Nrf2)-mediated antioxidant mechanisms. Since Nrf2 also acts as a key mediator of the nuclear factor-kappaB (NF-κB)-regulated inflammatory pathway, our present study investigated the anti-inflammatory mechanisms of a pomegranate emulsion (PE) during DENA-induced rat hepatocarcinogenesis. Rats were administered with PE (1 or 10 g/kg) 4 weeks before and 18 weeks following DENA initiation. There was a significant increase in hepatic expressions of inducible nitric oxide synthase, 3-nitrotyrosine, heat shock protein 70 and 90, cyclooxygenase-2 and NF-κB in DENA-exposed rat livers. PE dose-dependently suppressed all aforementioned elevated inflammatory markers. A conspicuous finding of this study involves lack of cardiotoxicity of PE as assessed by monitoring cardiac function using noninvasive echocardiography. Our results provide substantial evidence that suppression of the inflammatory cascade through modulation of NF-κB signaling pathway may represent a novel mechanism of liver tumor inhibitory effects of PE against experimental hepatocarcinogenesis. Data presented here coupled with those of our earlier study underline the importance of simultaneously targeting two interconnected molecular circuits, namely, Nrf2-mediated redox signaling and NF-κB-regulated inflammatory pathway, by pomegranate phytoconstituents to achieve chemoprevention of HCC.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Inflamação/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Lythraceae/química , Extratos Vegetais/farmacologia , Animais , Anticarcinógenos/farmacologia , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/metabolismo , Ciclo-Oxigenase 2/metabolismo , Dietilnitrosamina/toxicidade , Ecocardiografia , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Coração/fisiologia , Inflamação/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Sprague-Dawley , Tirosina/análogos & derivados , Tirosina/metabolismo
13.
Curr Cancer Drug Targets ; 12(9): 1244-57, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22873220

RESUMO

Hepatocellular carcinoma (HCC), considered to be one of the most lethal cancers with almost > 1 million deaths reported annually worldwide, remains a devastating disease with no known effective cure. Hence, chemopreventive strategies come into play, offering an effective and safe mode of treatment, ideal to ward off potential cancer risks and mortality. A major predisposing condition, pertinent to the development and progression of HCC is oxidative stress. We previously reported a striking chemopreventive effect of anthocyanin-rich black currant skin extract (BCSE) against diethylnitrosamine (DENA)-initiated hepatocarcinogenesis in rats. The current study aims to elucidate the underlying antioxidant mechanisms of black currant anthocyanins implicated in the previously observed chemopreventive effects against experimental hepatocarcinogenesis. Dietary BCSE (100 and 500 mg/kg) administered four weeks before and 18 weeks after DENA challenge decreased abnormal lipid peroxidation, protein oxidation, and expression of inducible nitric oxide synthase (iNOS) and 3-nitrotyrosine (3-NT) in a dose-responsive fashion. Mechanistic studies revealed that BCSE upregulated the gene expression of a number of hepatic antioxidant and carcinogen detoxifying enzymes, such as NAD(P)H:quinone oxidoreductase, glutathione S-transferase, and uridine diphosphate-glucuronosyltransferase isoenzymes, in DENA-initiated animals. Protein and mRNA expressions of nuclear factor E2-related factor 2 (Nrf2) were substantially elevated with BCSE treatment, providing a direct evidence of a coordinated activation of the Nrf2-regulated antioxidant pathway, which led to the upregulation of a variety of housekeeping genes. The results of our study provide substantial evidence that black currant bioactive anthocyanins exert chemopreventive actions against DENA-inflicted hepatocarcinogenesis by attenuating oxidative stress through activation of Nrf2 signaling pathway.


Assuntos
Antocianinas/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Neoplasias Hepáticas Experimentais/prevenção & controle , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fitoterapia , Ribes/química , Alquilantes/toxicidade , Animais , Antioxidantes/uso terapêutico , Western Blotting , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/metabolismo , Dieta , Dietilnitrosamina/toxicidade , Glutationa Transferase , Técnicas Imunoenzimáticas , Peroxidação de Lipídeos/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/genética , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Tirosina/análogos & derivados , Tirosina/metabolismo
14.
Curr Cancer Drug Targets ; 12(9): 1095-118, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22873221

RESUMO

Hepatocellular carcinoma (HCC) remains one of the most lethal cancers in the world. Since current treatment options including surgical resection and liver transplantation offer limited therapeutic benefits, there exists a need to evaluate novel therapeutic strategies for the amelioration of HCC. Hepatic tumors are highly vascularized, possessing a rich network of blood vessels and capillaries and there exist an angiogenic component to the tumor growth observed in HCC. Thus, anti-angiogenic therapy has been suggested to possess tremendous therapeutic potential in the treatment of HCC. The process of angiogenesis involves multiple biochemical checkpoints and signaling steps, and thus providing a multitude of opportunities for therapeutic intervention. In this review, we highlight the role of angiogenesis and its use as a therapeutic strategy for HCC. The first part of the article reviews the angiogenic mechanisms with particular emphasis on the multitude of biochemical factors, such as receptors, enzymes and cytokines involved in the complex interplay of new capillary growth. Next, we present the pre-clinical studies which elucidate the anti-angiogenic effects of both dietary and non-dietary agents in animal models of HCC. Of particular interest is the examination of the effects of the antiangiogenic agents on the various angiogenic markers in the hepatic tissue of the animal challenged either with a hepatocarcinogen or xenografted with hepatic neoplastic cells. The review also highlights the clinical investigations carried out in HCC patients to evaluate the therapeutic potential of pharmacological agents with proven anti-angiogenic properties. Finally, the future directions as well as the benefits and potential challenges involved in the use of antiangiogenic pharmacotherapy in the treatment of HCC are also discussed.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Neovascularização Patológica/prevenção & controle , Animais , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia
15.
Curr Cancer Drug Targets ; 12(9): 1191-232, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22873222

RESUMO

Hepatocellular carcinoma (HCC), one of the most common and lethal cancers, is a growing menace in modern society. Until recently, the majority of detected cases of liver cancer have been found in the developing nations of Asia and Africa; however, its occurrence has significantly increased in the United States. HCC occurs due to several etiologies, such as alcoholism, dietary carcinogens, iron overload, viral hepatitis, as well as several hepatic chronic diseases. In view of the limited treatment options, such as surgery and transplantation, a critical need exists to examine alternative approaches. The use of phytochemicals obtained from dietary sources provides a novel and fascinating preventive and therapeutic approach against HCC. Dietary phytochemicals possess potent antioxidant and anti-inflammatory properties which are extremely critical to combat the significant oxidative stress and inflammation implicated in liver cancer. An impressive number of phytochemicals have shown considerable promise as candidates for the prevention and treatment of HCC. In this article, we systematically review the in vivo pre-clinical evidence documenting the chemopreventive and therapeutic potential of several important dietary phytochemicals in HCC. This review critically examines the molecular mechanisms of the pharmacological effects of the aforementioned animal studies. Clinical and epidemiological studies are also highlighted in this review. Emerging issues such as bioavailability, dose optimization, targeted drug delivery, role of botanical extracts and synergy are also discussed. Finally, current challenges, limitations, future directions, innovative concepts and novel hypotheses for the use of dietary phytochemicals in the chemoprevention and amelioration of human HCC are presented.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Dieta , Neoplasias Hepáticas/prevenção & controle , Terapia de Alvo Molecular , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia
16.
Expert Opin Investig Drugs ; 21(8): 1123-40, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22668065

RESUMO

INTRODUCTION: Curcumin, a dietary polyphenol found in the curry spice turmeric, possesses potent antioxidant and anti-inflammatory properties and an ability to modulate multiple targets implicated in the pathogenesis of chronic illness. Curcumin has shown therapeutic potential for neurodegenerative diseases including Alzheimer's disease (AD) and Parkinson's disease (PD). AREAS COVERED: This article highlights the background and epidemiological evidence of curcumin's health benefits and its pharmacodynamic and pharmacokinetic profile. Curcumin's ability to counteract oxidative stress and inflammation and its capacity to modulate several molecular targets is reviewed. We highlight the neuroprotective properties of curcumin including pre-clinical evidence for its pharmacological effects in experimental models of AD and PD. The bioavailability and safety of curcumin, the development of semi-synthetic curcuminoids as well as novel formulations of curcumin are addressed. EXPERT OPINION: Curcumin possesses therapeutic potential in the amelioration of a host of neurodegenerative ailments as evidenced by its antioxidant, anti-inflammatory and anti-protein aggregation effects. However, issues such as limited bioavailability and a paucity of clinical studies examining its therapeutic effectiveness in illnesses such as AD and PD currently limit its therapeutic outreach. Considerable effort will be required to adapt curcumin as a neuroprotective agent to be used in the treatment of AD, PD and other neurodegenerative diseases.


Assuntos
Curcumina/farmacologia , Curcumina/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Animais , Curcumina/efeitos adversos , Curcumina/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Humanos , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/efeitos adversos , Fármacos Neuroprotetores/farmacocinética , Estresse Oxidativo/efeitos dos fármacos
17.
Food Funct ; 3(8): 795-809, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22673662

RESUMO

The blackcurrant (Ribes nigrum L., Grossulariceae), a small, perennial shrub native to central Europe and northern Asia, is cultivated throughout the world, including the United States. In addition to its anecdotal use in traditional herbal medicine, modern laboratories have demonstrated the potent anti-inflammatory, antioxidant and antimicrobial effects of blackcurrant constituents on a myriad of disease states. The properties of the blackcurrants are conferred from its biochemical constituents, some of which include anthocyans (specifically delphinidin-3-O-glucoside, delphinidin-3-O-rutinoside, cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside), flavonols, phenolic acids and polyunsaturated fatty acids. A plethora of studies have been published with regards to its various therapeutic applications. This article attempts to summarize these studies, providing a general overview of the research in this field. Several studies focus on the therapeutic potential of blackcurrants with regards to hypertension and other cardiovascular-associated illnesses, neoplastic, neurodegenerative and ocular diseases, nephrolithiasis, and diabetic neuropathy. Safety concerns and future directions are also mentioned, suggesting the critical examination of the exact mechanism of action, specific radical-scavenging capabilities of the blackcurrants and the crucial need for well-designed clinical trials to ensure the successful use of blackcurrants in a clinical setting.


Assuntos
Promoção da Saúde , Ribes , Antocianinas/análise , Anti-Infecciosos , Anti-Inflamatórios , Antineoplásicos Fitogênicos , Antioxidantes , Ácidos Graxos Insaturados/análise , Flavonoides/análise , Frutas/química , Humanos , Fitoterapia , Extratos Vegetais/efeitos adversos , Extratos Vegetais/farmacocinética , Extratos Vegetais/farmacologia , Ribes/química
18.
Neurochem Int ; 60(8): 806-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22710395

RESUMO

Dimebon is an anti-histamine with central nervous system activity. In this report the effects of dimebon as a neuroprotectant in animal models of Parkinson's disease were tested as assessed in methamphetamine- and MPTP-induced striatal dopaminergic toxicity. Dimebon (1mg/kg) administered at 30 min prior to methamphetamine (40mg/kg) significantly reduced the amount of striatal dopamine depletion in mice, without altering the initial methamphetamine-induced increase in body temperature. In contrast, dimebon at either 1 or 25mg/kg administered at 30 min prior to MPTP (35 mg/kg) was unable to prevent MPTP-induced striatal dopamine loss as determined at 7 days post-methamphetamine/MPTP. These data suggest that dimebon may be exerting a neurotoxin specific neuroprotective effect upon the striatal dopaminergic system and may serve as an important tool for discriminating the mechanistic basis of these two dopaminergic neurotoxins.


Assuntos
Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Indóis/farmacologia , Metanfetamina/farmacologia , Animais , Corpo Estriado/metabolismo , Sinergismo Farmacológico , Camundongos , Camundongos Endogâmicos C57BL
19.
Neurotoxicol Teratol ; 34(3): 338-43, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22521941

RESUMO

Intact male CD-1 mice received an injection of testosterone propionate (TP--5 ug), progesterone (P--5 mg), the oil vehicle or remained untreated (control). At 24 hours after hormonal treatments the mice received an injection of methamphetamine (MA--40 mg/kg) and rectal temperatures were measured. At 5 days post-MA, assays were performed to assess effects of these treatments. Maximal increases in body temperatures, that were significantly greater than oil-treated controls, were obtained in TP-treated mice. At 5 days post-MA, maximal weight reductions were obtained with TP-treated mice, while P-treated mice showed no significant decrease between the pre- versus post-MA determinations. Striatal dopamine concentrations showed maximal reductions and heat-shock protein-70 maximal increases in the TP group, with both differing significantly as compared with all other groups. Protein levels of dopamine transporters were significantly decreased in P-treated mice, while vesicular monoamine transporter-2 was significantly decreased in TP-treated mice. Taken together, these results suggest that testosterone exacerbates the deleterious effects of MA within male mice as indicated by a number of markers related to neurotoxicity. The changes in markers as associated with this enhanced neurotoxicity suggest that TP may increase thermal/energy responses and/or oxidative stress to produce this effect.


Assuntos
Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Metanfetamina/toxicidade , Síndromes Neurotóxicas/etiologia , Propionato de Testosterona/farmacologia , Animais , Biomarcadores/metabolismo , Western Blotting , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Corpo Estriado/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Sinergismo Farmacológico , Proteínas de Choque Térmico HSP70/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Síndromes Neurotóxicas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas Vesiculares de Transporte de Monoamina/metabolismo
20.
Curr Pharm Biotechnol ; 13(1): 218-28, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21466422

RESUMO

Primary liver cancer, also known as hepatocellular carcinoma (HCC), is one of the most lethal cancers having worldwide prevalence. Although most HCC cases are reported in the developing countries of Asia and Africa, there has been an alarming increase in HCC cases in Western Europe as well as United States. Chronic liver diseases, viral hepatitis, alcoholism as well as dietary carcinogens, such as aflatoxins and nitrosoamines, contribute to HCC. Liver transplantation as well as surgical resection at best offer limited treatment options. Thus, there exists a critical need to investigate and evaluate possible alternative chemopreventive and therapeutic strategies which may be effective in the control of liver cancer. HCC, most often, develops and progresses in a milieu of oxidative stress and inflammation. Phytochemicals, such as dietary polyphenols endowed with potent antioxidant as well as anti-inflammatory properties, provide a suitable alternative in affording alleviation of HCC. Curcumin, the principal polyphenolic curcuminoid, obtained from the turmeric rhizome Curcuma longa has long been used to cure several chronic ailments, such as neoplastic and neurodegenerative diseases. Studies suggest that curcumin may have antitumor, antioxidant, and anti-inflammatory properties. This article reviews the effects of curcumin in preclinical in vitro and in vivo models of HCC with particular emphasis to its antioxidant, apoptotic and anti-inflammatory effects as well as involvement in various molecular signaling mechanisms. This review also discusses potential challenges involved in the use of curcumin in HCC, such as bioavailability, pharmacokinetics, drug delivery as well as paucity of clinical studies.


Assuntos
Anticarcinógenos/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Curcumina/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Animais , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Humanos , Neoplasias Hepáticas/prevenção & controle
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