Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
Pharm Biol ; 61(1): 1135-1151, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37497554

RESUMO

CONTEXT: Arjunolic acid (AA) is a triterpenoid saponin found in Terminalia arjuna (Roxb.) Wight & Arn. (Combretaceae). It exerts cardiovascular protective effects as a phytomedicine. However, it is unclear how AA exerts the effects at the molecular level. OBJECTIVE: This study investigates the cardioprotective effects of arjunolic acid (AA) via MyD88-dependant TLR4 downstream signaling marker expression. MATERIALS AND METHODS: The MTT viability assay was used to assess the cytotoxicity of AA. LPS induced in vitro cardiovascular disease model was developed in H9C2 and C2C12 myotubes. The treatment groups were designed such as control (untreated), LPS control, positive control (LPS + pyrrolidine dithiocarbamate (PDTC)-25 µM), and treatment groups were co-treated with LPS and three concentrations of AA (50, 75, and 100 µM) for 24 h. The changes in the expression of TLR4 downstream signaling markers were evaluated through High Content Screening (HCS) and Western Blot (WB) analysis. RESULTS: After 24 h of co-treatment, the expression of TLR4, MyD88, MAPK, JNK, and NF-κB markers were upregulated significantly (2-6 times) in the LPS-treated groups compared to the untreated control in both HCS and WB experiments. Evidently, the HCS analysis revealed that MyD88, NF-κB, p38, and JNK were significantly downregulated in the H9C2 myotube in the AA treated groups. In HCS, the expression of NF-κB was downregulated in C2C12. Additionally, TLR4 expression was downregulated in both H9C2 and C2C12 myotubes in the WB experiment. DISCUSSION AND CONCLUSIONS: TLR4 marker expression in H9C2 and C2C12 myotubes was subsequently decreased by AA treatment, suggesting possible cardioprotective effects of AA.


Assuntos
NF-kappa B , Triterpenos , Lipopolissacarídeos/farmacologia , Fibras Musculares Esqueléticas/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Triterpenos/farmacologia , Animais , Camundongos , Ratos
2.
Integr Med (Encinitas) ; 20(2): 26-30, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34377091

RESUMO

Chronic pain is a condition affecting millions of Americans annually. Veterans, as a population cohort, are often afflicted with chronic pain that is more complex, with higher rates of psychiatric and social comorbidities when compared to the general population. In this case report, we describe a veteran with major depressive disorder and alcohol abuse afflicted by high-impact chronic pain, initially treated and then maintained on high dose opioids developing dependency, who was successfully weaned off and achieved adequate pain management using complementary and alternative medicine, namely Qi gong. We conclude that complementary and alternative medicine offers a safe and effective option in providing pain relief using nonpharmacological means and thus avoiding undesired effects. We postulate that as research in this area increases, the demand for and the availability of complementary and alternative medicine will expand.

3.
Life Sci ; 260: 118182, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781063

RESUMO

BACKGROUND: Chronic diseases are a major cause of mortality worldwide, and despite the recent development in treatment modalities, synthetic drugs have continued to show toxic side effects and development of chemoresistance, thereby limiting their application. The use of phytochemicals has gained attention as they show minimal side effects. Diosgenin is one such phytochemical which has gained importance for its efficacy against the life-threatening diseases, such as cardiovascular diseases, cancer, nervous system disorders, asthma, arthritis, diabetes, and many more. AIM: To evaluate the literature available on the potential of diosgenin and its analogs in modulating different molecular targets leading to the prevention and treatment of chronic diseases. METHOD: A detailed literature search has been carried out on PubMed for gathering information related to the sources, biosynthesis, physicochemical properties, biological activities, pharmacokinetics, bioavailability and toxicity of diosgenin and its analogs. KEY FINDINGS: The literature search resulted in many in vitro, in vivo and clinical trials that reported the efficacy of diosgenin and its analogs in modulating important molecular targets and signaling pathways such as PI3K/AKT/mTOR, JAK/STAT, NF-κB, MAPK, etc., which play a crucial role in the development of most of the diseases. Reports have also revealed the safety of the compound and the adaptation of nanotechnological approaches for enhancing its bioavailability and pharmacokinetic properties. SIGNIFICANCE: Thus, the review summarizes the efficacy of diosgenin and its analogs for developing as a potent drug against several chronic diseases.


Assuntos
Doença Crônica/tratamento farmacológico , Diosgenina/uso terapêutico , Animais , Disponibilidade Biológica , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Fenômenos Químicos , Doença Crônica/prevenção & controle , Diosgenina/análogos & derivados , Diosgenina/farmacocinética , Humanos , Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico , Doenças do Sistema Nervoso/tratamento farmacológico , Fitoterapia , PubMed , Sementes/química , Transdução de Sinais/efeitos dos fármacos , Trigonella
4.
Drug Des Devel Ther ; 11: 337-350, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28203057

RESUMO

BACKGROUND: The aim of this study was to evaluate the anticancer potential of Kelussia odoratissima. Several in vitro and in vivo biological assays were applied to explore the direct effect of an extract and bioactive compound of this plant against breast cancer cells and its possible mechanism of action. MATERIALS AND METHODS: K. odoratissima methanol extract (KME) was prepared, and MTT assay was used to evaluate the cytotoxicity. To identify the cytotoxic compound, a bioassay-guided investigation was performed on methanol extract. 8-Hydroxy-ar-turmerone was isolated as a bioactive compound. In vivo study was performed in the breast cancer rat model. LA7 cell line was used to induce the breast tumor. Histopathological and expression changes of PCNA, Bcl-2, Bax, p27 and p21 and caspase-3 were examined. The induction of apoptosis was tested using Annexin V-fluorescein isothiocyanate (FITC) assay. To confirm the intrinsic pathway of apoptosis, caspase-7 and caspase-9 assays were utilized. In addition, cell cycle arrest was evaluated. RESULTS: Our results demonstrated that K. odoratissima has an obvious effect on the arrest of proliferation of cancer cells. It induced apoptosis, transduced the cell death signals, decreased the threshold of mitochondrial membrane potential (MMP), upregulated Bax and downregulated Bcl-2. CONCLUSION: This study demonstrated that K. odoratissima exhibits antitumor activity against breast cancer cells via cell death and cell cycle arrest.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apiaceae/química , Apoptose/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Neoplasias Mamárias Experimentais/patologia , Extratos Vegetais/farmacologia , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
5.
Biomed Pharmacother ; 81: 439-452, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27261624

RESUMO

INTRODUCTION: Protective effects of Vitis Vinifera seed aqueous extract (VVSAE) against pancreatic dysfunctions and elevation of oxidative stress, inflammation and apoptosis in the pancreas in diabetes were investigated. Histopathological changes in the pancreas were examined under light microscope. METHODS: Blood and pancreas were collected from adult male diabetic rats receiving 28days treatment with VVSAE orally. Fasting blood glucose (FBG), glycated hemoglobin (HbA1c), insulin and lipid profile levels and activity levels of anti-oxidative enzymes (superoxide dismutase-SOD, catalase-CAT and glutathione peroxidase-GPx) in the pancreas were determined by biochemical assays. Histopathological changes in the pancreas were examined under light microscopy and levels of insulin, glucose transporter (GLUT)-2, tumor necrosis factor (TNF)-α, Ikkß and caspase-3 mRNA and protein were analyzed by real-time PCR (qPCR) and immunohistochemistry respectively. Radical scavenging activity of VVSAE was evaluated by in-vitro anti-oxidant assay while gas chromatography-mass spectrometry (GC-MS) was used to identify the major compounds in the extract. RESULTS: GC-MS analyses indicated the presence of compounds that might exert anti-oxidative, anti-inflammatory and anti-apoptosis effects. Near normal FBG, HbAIc, lipid profile and serum insulin levels with lesser signs of pancreatic destruction were observed following administration of VVSAE to diabetic rats. Higher insulin, GLUT-2, SOD, CAT and GPx levels but lower TNF-α, Ikkß and caspase-3 levels were also observed in the pancreas of VVSAE-treated diabetic rats (p<0.05 compared to non-treated diabetic rats). The extract possesses high in-vitro radical scavenging activities. CONCLUSION: In conclusions, administration of VVSAE to diabetic rats could help to protect the pancreas against oxidative stress, inflammation and apoptosis-induced damage while preserving pancreatic function near normal in diabetes.


Assuntos
Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/patologia , Extratos Vegetais/uso terapêutico , Substâncias Protetoras/uso terapêutico , Vitis/química , Animais , Antioxidantes/metabolismo , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Jejum/sangue , Comportamento Alimentar/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Hemoglobinas Glicadas , Inflamação/sangue , Inflamação/patologia , Insulina/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos/sangue , Masculino , Pâncreas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Sementes/química , Superóxido Dismutase/metabolismo , Água/química
6.
J Exp Clin Cancer Res ; 34: 147, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26643256

RESUMO

BACKGROUND: Natural compounds have been demonstrated to lower breast cancer risk and sensitize tumor cells to anticancer therapies. Recently, we demonstrated that vernodalin (the active constituent of the medicinal herb Centratherum anthelminticum seeds) induces apoptosis in breast cancer cell-lines. The aim of this work was to gain an insight into the underlying anticancer mechanism of vernodalin using in vitro and in vivo model. METHODS: Vernodalin was isolated through the bioassay guided fractionation from the seeds. The protein expression of p-Akt, PI3K, FOXO3a, Bim, p27kip1, cyclinD1, and cyclinE was examined by the Western blot analysis. Immunoprecipitation assays were performed to analyse Akt kinase activity. Small interfering RNA (siRNA) was used to study the role of FOXO3a upregulation and their targets during vernodalin treatment. Immunofluorescence, subcellular localisation of FOXO3a by Western blot was performed to analyse FOXO3a localisation in nucleus of breast cancer cells. Immunohistochemical analysis of PCNA, Ki67, p27kip1, FOXO3a and p-FOXO3a in the LA7-induced mammary gland tumor model was performed. RESULTS: Our results showed that vernodalin regulates cancer cell apoptosis through activation of FOXO transcription factors and its downstream targets (Bim, p27Kip1, p21Waf1/cip1, cyclin D1, cyclin E) as examined by Western blots. Furthermore, we showed that FOXO3a/PI3K-Akt played a significant role in vernodalin induced apoptosis in breast cancer cells. Immunoprecipitation assays showed Akt kinase activity was downregulated. Immunofluorescence, subcellular fractionation and Western blot showed FOXO3a accumulation in the nucleus of breast cancer cells after vernodalin treatment. Silencing of FOXO3a protected breast cancer cells against vernodalin induced apoptosis. The anti-tumor action of vernodalin was further confirmed by examining cell proliferative markers, PCNA and Ki67 in the LA7-induced mammary gland tumor model. We also corroborated our findings in vivo by showing upregulation of p27Kip1, FOXO3a and decrease in the p-FOXO3a level in vernodalin-treated breast tumor tissue. CONCLUSIONS: Our results suggest that PI3K-Akt/FOXOa pathway is a critical mediator of vernodalin-induced cytotoxicity and this compound could be further developed as a potential chemopreventive or chemotherapeutic agent for breast cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fatores de Transcrição Forkhead/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Modelos Animais de Doenças , Feminino , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/genética , Inativação Gênica , Humanos , Espaço Intracelular/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/farmacologia , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , Ratos , Sesquiterpenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Ethnopharmacol ; 175: 229-40, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26342523

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The art of Ayurveda and the traditional healing system in India have reflected the ethnomedicinal importance of the plant Woodfordia fruticosa Kurtz, which demonstrates its vast usage in the Ayurvedic preparations as well as in the management of diabetes by the traditional healers. AIMS OF STUDY: The study aimed to ascertain the antidiabetic potential of W. fruticosa flower methanolic extract (WF) on Streptozotocin (STZ)-nicotinamide-induced diabetic rat model. MATERIALS AND METHODS: Diabetes was induced in Sprague Dawley (SD) rats by STZ-nicotinamide and thereafter diabetic rats were treated with three different doses of WF (100, 200 and 400mg/kg body weight) respectively and glibenclamide as a positive control. Biochemical parameters such as blood glucose, serum insulin and C-peptide levels were measured with oxidative stress markers. Furthermore, histology of liver and pancreas was carried out to evaluate glycogen content and ß-cell structures. Moreover, immunohistochemistry and western blot analysis were performed on kidney and pancreas tissues to determine renal Bcl-2, pancreatic insulin and glucose transporter (GLUT-2, 4) protein expression in all the experimental groups. RESULTS: The acute toxicity study showed non-toxic nature of all the three doses of WF. Further, studies on diabetic rats exhibited anti-hyperglycemic effects by upregulating serum insulin and C-peptide levels. Similarly, WF shown to ameliorate oxidative stress by downregulating LPO levels and augmenting the antioxidant enzyme (ABTS). Furthermore, histopathological analysis demonstrate recovery in the structural degeneration of ß-cells mass of pancreas tissue with increase in the liver glycogen content of the diabetic rats. Interestingly, protective nature of the extract was further revealed by the immunohistochemical study result which displayed upregulation in the insulin and renal Bcl-2 expression, the anti apoptosis protein. Moreover, western blot result have shown slight alteration in the GLUT-2 and GLUT-4 protein expression with the highest dose of WFc treatment, that might have stimulated glucose uptake in the pancreas and played an important role in attenuating the blood glucose levels. CONCLUSION: The overall study result have demonstrated the potential of WF in the management of diabetes and its related complications, thus warrants further investigation on its major compounds with in depth mechanistic studies at molecular level.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Woodfordia , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Flores , Transportador de Glucose Tipo 2/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Glicogênio/metabolismo , Hiperglicemia/tratamento farmacológico , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Niacinamida , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Compostos Fitoquímicos/análise , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Estreptozocina
8.
Int J Biol Sci ; 11(5): 508-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25892959

RESUMO

Diabetes mellitus (DM) is a metabolic diseases characterized by hyperglycemia due to insufficient or inefficient insulin secretory response. This chronic disease is a global problem and there is a need for greater emphasis on therapeutic strategies in the health system. Phytochemicals such as flavonoids have recently attracted attention as source materials for the development of new antidiabetic drugs or alternative therapy for the management of diabetes and its related complications. The antidiabetic potential of flavonoids are mainly through their modulatory effects on glucose transporter by enhancing GLUT-2 expression in pancreatic ß cells and increasing expression and promoting translocation of GLUT-4 via PI3K/AKT, CAP/Cb1/TC10 and AMPK pathways. This review highlights the recent findings on beneficial effects of flavonoids in the management of diabetes with particular emphasis on the investigations that explore the role of these compounds in modulating glucose transporter proteins at cellular and molecular level.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Dieta/veterinária , Flavonoides/farmacologia , Transportador de Glucose Tipo 2/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Suplementos Nutricionais , Flavonoides/química , Transportador de Glucose Tipo 2/efeitos dos fármacos , Transportador de Glucose Tipo 4/efeitos dos fármacos , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Compostos Fitoquímicos
9.
Fitoterapia ; 102: 182-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25665941

RESUMO

Vindogentianine, a new indole alkaloid together with six known alkaloids, vindoline, vindolidine, vindolicine, vindolinine, perivine and serpentine were isolated from leaf extract (DA) of Catharanthus roseus (L.) G. Don. Their structures were elucidated by spectroscopic methods; NMR, MS, UV and IR. Vindogentianine is a dimer containing a vindoline moiety coupled to a gentianine moiety. After 24h incubation, vindogentianine exhibited no cytotoxic effect in C2C12 mouse myoblast and ß-TC6 mouse pancreatic cells (IC50>50µg/mL). Real-time cell proliferation monitoring also indicated vindogentianine had little or no effect on C2C12 mouse myoblast cell growth at the highest dose tested (200µg/mL), without inducing cell death. Vindogentianine exhibited potential hypoglycemic activity in ß-TC6 and C2C12 cells by inducing higher glucose uptake and significant in vitro PTP-1B inhibition. However, in vitro α-amylase and α-glucosidase inhibition assay showed low inhibition under treatment of vindogentianine. This suggests that hypoglycemic activity of vindogentianine may be due to the enhancement of glucose uptake and PTP-1B inhibition, implying its therapeutic potential against type 2 diabetes.


Assuntos
Alcaloides/química , Catharanthus/química , Hipoglicemiantes/química , Alcaloides Indólicos/química , Folhas de Planta/química , Alcaloides/isolamento & purificação , Animais , Linhagem Celular , Glucose/metabolismo , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Hipoglicemiantes/isolamento & purificação , Alcaloides Indólicos/isolamento & purificação , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Extratos Vegetais/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , alfa-Amilases/antagonistas & inibidores
10.
Drug Des Devel Ther ; 8: 1481-97, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25278746

RESUMO

Ferulago angulata is a medicinal plant that is traditionally known for its anti-inflammatory and antiulcer properties. The present study was aimed to evaluate its anticancer activity and the possible mechanism of action using MCF-7 as an in vitro model. F. angulata leaf extracts were prepared using solvents in the order of increasing polarity. As determined by MTT assay, F. angulata leaves hexane extract (FALHE) revealed the strongest cytotoxicity against MCF-7 cells with the half maximal inhibitory concentration (IC50) value of 5.3 ± 0.82 µg/mL. The acute toxicity study of FALHE provided evidence of the safety of the plant extract. Microscopic and flow cytometric analysis using annexin-V probe showed an induction of apoptosis in MCF-7 by FALHE. Treatment of MCF-7 cells with FALHE encouraged the intrinsic pathway of apoptosis, with cell death transducing signals that reduced the mitochondrial membrane potential with cytochrome c release from mitochondria to cytosol. The released cytochrome c triggered the activation of caspase-9. Meanwhile, the overexpression of caspase-8 suggested the involvement of an extrinsic pathway in the induced apoptosis at the late stage of treatment. Moreover, flow cytometric analysis showed that FALHE treatment significantly arrested MCF-7 cells in the G1 phase, which was associated with upregulation of p21 and p27 assessed by quantitative polymerase chain reaction. Immunofluorescence and the quantitative polymerase chain reaction analysis of MCF-7 cells after treatment with FALHE revealed an upregulation of Bax and a downregulation of Bcl-2 proteins. These findings proposed that FALHE suppressed the proliferation of MCF-7 cells via cell cycle arrest and the induction of apoptosis through intrinsic pathway.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apiaceae/química , Apoptose/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Células Hep G2 , Humanos , Irã (Geográfico) , Células MCF-7 , Extratos Vegetais/química , Folhas de Planta/química , Ratos , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA