Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-38283879

RESUMO

Dementia is a progressive brain disorder that affects memory, thinking and behaviour. It is a major global public health concern, with an estimated 55 million people worldwide living with the condition. In the UK, there is an estimated 944,000 people with dementia. This number is expected to double by 2050. Dementia is a major cause of disability and dependency, and it places a significant burden on families and carers. The current level of dementia education in pre-registration nursing programmes in the UK is inadequate. There are no pre-registration nursing educational programmes that offer dementia as a speciality. This is a major concern, as nurses are the primary providers of care to people with dementia. This article argues that dementia should be established as a branch of pre-registration nursing education that leads to a Registered Nurse (RN) - Dementia. This could help to address the shortage of specialist dementia nurses in the country. This article provides an important suggestion for countries with a shortage of specialist dementia nurses to consider establishing a stand-alone pre-registration branch of dementia nurse education. This would result in a more specialised workforce with the skills and knowledge to provide high-quality care to people with dementia.

2.
Nurs Inq ; 31(2): e12602, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37735926

RESUMO

This paper explores the explanatory models of mental challenges among Black Africans in England. It argues that understanding these models is critical for providing culturally appropriate care to this population. The study employed qualitative methodology, and interpretative phenomenological analysis (IPA). Twelve mental health service users who are living in England and self-identified as first or second-generation Black Africans were purposively selected. The data were gathered using face-to-face semistructured interviews. Data were manually analysed in accordance with IPA concepts of searching for common, unique and idiosyncratic themes across transcripts. The findings revealed three themes Black Africans associated to their explanatory model of mental health challenges: complexities of migration, African-centred worldview and negative life experiences. To help alleviate the Eurocentric nature of mental health practice in England, it is hoped that this explanatory model will become an integral part of mental health practice in England and around the world.

3.
Molecules ; 28(17)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37687086

RESUMO

Cancers utilize sugar residues such as sialic acids (Sia) to improve their ability to survive. Sia presents a variety of functional group alterations, including O-acetylation on the C6 hydroxylated tail. Previously, sialylation has been reported to suppress EGFR activation and increase cancer cell sensitivity to Tyrosine Kinase Inhibitors (TKIs). In this study, we report on the effect of deacetylated Sia on the activity of three novel EGFR-targeting Cucurbitacin-inspired estrone analogs (CIEAs), MMA 294, MMA 321, and MMA 320, in lung and colon cancer cells. Acetylation was modulated by the removal of Sialate O-Acetyltransferase, also known as CAS1 Domain-containing protein (CASD1) gene via CRISPR-Cas9 gene editing. Using a variety of cell-based approaches including MTT cell viability assay, flow cytometry, immunofluorescence assay and in-cell ELISA we observed that deacetylated Sia-expressing knockout cells (1.24-6.49 µM) were highly sensitive to all CIEAs compared with the control cells (8.82-20.97 µM). Apoptosis and varied stage cell cycle arrest (G0/G1 and G2/M) were elucidated as mechanistic modes of action of the CIEAs. Further studies implicated overexpression of CIEAs' cognate protein target, phosphorylated EGFR, in the chemosensitivity of the deacetylated Sia-expressing knockout cells. This observation correlated with significantly decreased levels of key downstream proteins (phosphorylated ERK and mTOR) of the EGFR pathway in knockout cells compared with controls when treated with CIEAs. Collectively, our findings indicate that Sia deacetylation renders lung and colon cancer cells susceptible to EGFR therapeutics and provide insights for future therapeutic interventions.


Assuntos
Neoplasias do Colo , Ácido N-Acetilneuramínico , Estrona/farmacologia , Neoplasias do Colo/tratamento farmacológico , Receptores ErbB , Pulmão
4.
Front Oncol ; 13: 1145333, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377914

RESUMO

Cancers utilize sugar residues to engage in multidrug resistance. The underlying mechanism of action involving glycans, specifically the glycan sialic acid (Sia) and its various functional group alterations, has not been explored. ATP-binding cassette (ABC) transporter proteins, key proteins utilized by cancers to engage in multidrug resistant (MDR) pathways, contain Sias in their extracellular domains. The core structure of Sia can contain a variety of functional groups, including O-acetylation on the C6 tail. Modulating the expression of acetylated-Sias on Breast Cancer Resistance Protein (BCRP), a significant ABC transporter implicated in MDR, in lung and colon cancer cells directly impacted the ability of cancer cells to either retain or efflux chemotherapeutics. Via CRISPR-Cas-9 gene editing, acetylation was modulated by the removal of CAS1 Domain-containing protein (CASD1) and Sialate O-Acetyl esterase (SIAE) genes. Using western blot, immunofluorescence, gene expression, and drug sensitivity analysis, we confirmed that deacetylated Sias regulated a MDR pathway in colon and lung cancer in early in vitro models. When deacetylated Sias were expressed on BCRP, colon and lung cancer cells were able to export high levels of BCRP to the cell's surface, resulting in an increased BCRP efflux activity, reduced sensitivity to the anticancer drug Mitoxantrone, and high proliferation relative to control cells. These observations correlated with increased levels of cell survival proteins, BcL-2 and PARP1. Further studies also implicated the lysosomal pathway for the observed variation in BCRP levels among the cell variants. RNASeq data analysis of clinical samples revealed higher CASD1 expression as a favorable marker of survival in lung adenocarcinoma. Collectively, our findings indicate that deacetylated Sia is utilized by colon and lung cancers to engage in MDR via overexpression and efflux action of BCRP.

5.
Nurs Inq ; 29(4): e12484, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36302717

RESUMO

Watchful waiting is a concept that is traditionally not associated with severe and enduring mental illness. This paper, however, boldly argues that the concept could be used as a ground-breaking and accessible antidote to the perceived inequality experienced by black service users experiencing both mild and severe mental illnesses in England. The novel concepts proposed in this paper are not intended to be consensual, but rather uncompromising to provoke critical thinking in mental health practice. A conceptual framework for watchful waiting in mental health is suggested.


Assuntos
Transtornos Mentais , Serviços de Saúde Mental , Humanos , Conduta Expectante , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Inglaterra
6.
Nurs Inq ; 29(1): e12436, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34124816

RESUMO

The aim of this paper was to explore the experiences of perceived prejudices faced in England by Black African mental health nurses. Purposive sampling was used to identify five nurses from sub-Saharan Africa. They were interviewed using face-to-face semi-structured interviews. Data were analysed using interpretative phenomenological analysis (IPA). The findings were reported under two superordinate themes: Judging a book by its cover and opportunities. The findings showed that Black African nurses experience deep-rooted discrimination and marginalisation. Aside from that, because of their ethnicity and the fact that they speak English as a second language, they face discrimination and have difficulty achieving leadership roles. These findings provide key stakeholders, such as nursing trade unions and professional associations, as well as NHS employers, with the opportunity to act to counter hegemony in the NHS and recognise that discriminatory and racially related barriers hinder Black African nurses from reaching their full professional potential.


Assuntos
População Negra , Saúde Mental , Etnicidade , Humanos , Preconceito , Pesquisa Qualitativa
7.
J Psychiatr Ment Health Nurs ; 27(4): 352-361, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31913535

RESUMO

WHAT IS KNOWN ON THE SUBJECT?: Religion plays important role in recovery from mental illness. Religion can have both positive and negative effects on recovery. WHAT DOES THIS PAPER ADD TO EXISTING KNOWLEDGE?: It is conceivable for Black African service users (BASUs) to engage with the mainstream mental health services at the onset of their symptoms. BASUs see mental illness and recovery through the lens of religion. They mostly use Pentecostalism and traditional African healing systems to aid their recovery. The mainstream mental health system and the traditional African healing system exist in harmony for BASUs who are open to simultaneously access both services. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: There is a need to recognize that most Black Africans have unique ways of practising their Christianity. Thus, broad changes are needed in the services to support religious coping tailored to the individual persons in their recovery journey. There is a need for service providers and healthcare professionals to integrate Pentecostalism and traditional African healing systems into the recovery processes. It should equally be recognized that such changes could trigger confusion, dilemmas and paradoxes. Service providers and healthcare professionals must build partnership and collaborative working with cultural practitioners and the clergy from the Black African communities to facilitate recovery and address any misunderstandings. ABSTRACT: Introduction Religion is an important impetus for recovery. However, there has been little work examining the role of religion in recovery for Black African service users (BASUs) in England. Aim The aim of this study was to explore how religion influences recovery from mental illness for BASUs in England. Method Twelve Black African service users were purposively selected and interviewed using face-to-face semi-structured interviews. Data were analysed using interpretative phenomenological analysis (IPA). Results The study generates fascinating insights that BASUs views about mental illness and recovery are influenced by Pentecostalism and traditional African healing systems. Discussion The participants' perceptions of their mental illness experiences and recovery which are characterized by the pragmatism of Pentecostalism and cultural beliefs are consistent with what is reported in the literature. Implications for practice The findings of the study show that broad changes are needed to accommodate the religious coping of BASUs in their recovery journey.


Assuntos
População Negra/etnologia , Transtornos Mentais/etnologia , Transtornos Mentais/reabilitação , Religião e Psicologia , Adulto , Inglaterra/etnologia , Humanos , Pesquisa Qualitativa
8.
J Res Nurs ; 24(1-2): 104-118, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34394513

RESUMO

BACKGROUND: Research conceptualising recovery is predominantly Eurocentric. This paper develops the conceptualisation of recovery by Black African service users. AIMS: Our aim was to explore Black African service users' experiences of recovery from mental illness and to understand how they conceptualise recovery. METHODS: Using a qualitative research approach and interpretative phenomenological analysis (IPA), semi-structured interviews were conducted with 12 Black African service users recovering from mental illness in England. RESULTS: Participants conceptualised recovery as a pragmatic and subjective concept distributed across a continuum of clinical, functional and spiritual dimensions, resilience, identity and their social and cultural backgrounds. CONCLUSIONS: It seems critical for all stakeholders to ensure that these components are embedded in recovery-oriented services for Black African service users.

9.
J Evid Based Integr Med ; 23: 2515690X18810001, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30392393

RESUMO

Drug interactions are key reasons for adverse drug reactions and attrition from market. Major infectious diseases causing morbidity/mortality in Ghana are malaria, tuberculosis, and HIV/AIDS. In this study, plant medicines commonly used to treat/manage these diseases in Ghana were investigated for their potential to modulate rat cytochrome P450 enzyme activities. Fluorescence and high-performance liquid chromatography-based assays were used to assess effects of antimalarial plant medicines, Fever (FEV), Mal-TF (MAL), and Kantinka terric (KT); anti-TB medicines, Chestico (CHES), CA + ST Pains + HWNT (TF), and Kantinka herbatic (KHB); and anti-HIV/AIDS medicines, Wabco (WAB), AD + T/AD (LIV) and Kantinka BA (KBA) on rat liver microsomal cytochrome P450 enzyme activities. Effects of medicines on rat biochemical and hematological parameters were also assessed. Generally, the medicines altered microsomal CYP1A1/1A2, CYP2B1/2B2, CYP2C9, and CYP2D6 activities. Only KBA elicited an increase (80%) in CYP1A1/1A2 activity. FEV, MAL, CHES, WAB, and LIV strongly inhibited the enzyme activity. All the medicines significantly inhibited CYP2C9 (24%-80%) activity. CYP2D6 activity increased after treatment with MAL, KBA, LIV, and TF. Also, MAL, WAB, LIV, KHB, and CHES increased CYP2B1/2B2 activity, while KT decrease the activity. Generally, the medicines altered liver function in the rats. Cholesterol levels declined after KBA treatment only. White and red blood cell counts, hemoglobin and hematocrit levels were significantly reduced in KT- and KBA-treated rats. Our results suggest that use of the medicines could have implications for drug interactions and safety, particularly if the medicines are administered over prolonged periods. Further investigations are imperative to establish clinical relevance of these results.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Antimaláricos/administração & dosagem , Antituberculosos/administração & dosagem , Sistema Enzimático do Citocromo P-450/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Infecções por HIV/tratamento farmacológico , Infecções por HIV/enzimologia , Humanos , Malária/tratamento farmacológico , Malária/enzimologia , Masculino , Microssomos Hepáticos/enzimologia , Ratos , Ratos Sprague-Dawley , Tuberculose/tratamento farmacológico , Tuberculose/enzimologia
10.
J Evid Based Integr Med ; 23: 2515690X18790723, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30088418

RESUMO

There are numerous herbal products on the Ghanaian market that are purported to cure various ailments, including cancer. However, scientific investigations on efficacy and toxicity of most of these products are not done. The aim of the study was to assess the anticancer potentials of herbal products on the Ghanaian market. Antiproliferative effects of Kantinka BA (K-BA), Kantinka Herbaltics (K-HER), Centre of Awareness (COA), a stomach (STO) and multicancer (MUT) product were evaluated in vitro using liver (Hep G2), breast (MCF-7), prostate (PC-3 and LNCaP), and blood (Jurkat) cancer cell lines. Cytotoxicity of the medicinal products was assessed using tetrazolium-based colorimetric assay, and total phenolic content and antioxidant activity of the products were determined using Folin-Ciocalteau and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, respectively. Phytochemical screening resulted in the detection of terpenoids and flavonoids in most of the products, and alkaloids were detected in only MUT. Tannins were absent from all the products. The highest and lowest concentrations of phenolics were recorded for MUT and K-BA, respectively. The highest and lowest antioxidant activities were measured for MUT and K-HER, respectively. Only 2 products (STO and MUT) were cytotoxic to Hep G2 cells; with MUT being the only product that was cytotoxic to MCF-7 cells. All but K-BA were cytotoxic to PC-3 cells, while all products except K-HER were cytotoxic to LNCaP and Jurkat cells. The study thus confirms that the herbal products have selective cytotoxic activities against the tested cancer cell lines. However, comprehensive toxicity studies must be conducted to establish their safety.

11.
Nurse Res ; 26(1): 13-18, 2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29787036

RESUMO

BACKGROUND: There is a growing body of literature providing reflective accounts and critical examination of the challenges faced by insider researchers. However, there is little research about the specific challenges that black African insider nurse researchers face. AIM: To reflect on the complexities black African insider nurse researchers face in the context of research sites, participants and the interpretation of data. DISCUSSION: Insider researchers are susceptible to various entanglements and dilemmas. Belonging to the same racial and cultural backgrounds as participants is advantageous, although caution is needed. Adoption of the emergent reflective model as an archetypal template can help future insider researchers considerably. CONCLUSION: Being an insider researcher comes with advantages and disadvantages. Entanglement and role ambiguity are some of the disadvantages. However, unspoken understandings with the participants provide insightful meanings into their experiences. IMPLICATION FOR PRACTICE: Reflectivity is crucial to the quality and rigour of qualitative studies. The challenge for future insider researchers is to show explicit awareness, tactfulness, sensitivity, commitment and rigour in their research.


Assuntos
População Negra/psicologia , Etnicidade/psicologia , Pesquisa em Enfermagem/organização & administração , Pesquisadores/psicologia , Adulto , População Negra/estatística & dados numéricos , Inglaterra , Etnicidade/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Pesquisadores/estatística & dados numéricos
12.
Phytother Res ; 32(8): 1617-1630, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29733118

RESUMO

Trypanosomiasis, leishmaniasis, and malaria are protozoan infections of public health importance with thousands of new cases recorded annually. Control of these infection(s) with existing chemotherapy is limited by drug toxicity, lengthy parenteral treatment, affordability, and/or the emergence of resistant strains. Medicinal plants on the other hand are used in the treatment of various infectious diseases although their chemical properties are not fully evaluated. In this study, we screened 112 crude extracts from 72 selected Ghanaian medicinal plants for anti-Trypanosoma, anti-Leishmania, and anti-Plasmodium activities in vitro and investigated their mechanisms of action. Twenty-three extracts from 20 plants showed significant antiprotozoan activity against at least 1 of 3 protozoan parasites screened with IC50 values less than 20 µg/ml. Eleven extracts showed high anti-Trypanosoma activity with Bidens pilosa whole plant and Morinda lucida leaf extracts recording the highest activities. Their IC50 (selectivity index [SI]) values were 5.51 µg/ml (35.00) and 5.96 µg/ml (13.09), respectively. Nine extracts had high anti-Leishmania activity with Annona senegalensis and Cassia alata leaf extracts as the most active. Their IC50 (SI) values were 10.8 µg/ml (1.50) and 10.1 µg/ml (0.37), respectively. Six extracts had high anti-Plasmodium activity with the leaf and stem-bark extracts of Terminalia ivorensis recording the highest activity. Their IC50 (SI) values were 7.26 µg/ml (129.36) and 17.45 µg/ml (17.17), respectively. Only M. lucida at 25 µg/ml induced significant apoptosis-like cell death in Trypanosoma parasites. Anti-Leishmania active extracts induced varying morphological changes in Leishmania parasites such as multiple nuclei and/or kinetoplast, incomplete flagella division, or nuclear fragmentation. Active extracts may be potential sources for developing new chemotherapy against these infections.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Plasmodium/efeitos dos fármacos , Trypanosoma/efeitos dos fármacos , Apoptose , Gana , Humanos , Células Jurkat
14.
Anal Cell Pathol (Amst) ; 2018: 4675380, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30631746

RESUMO

Schistosomiasis is a neglected tropical disease that affects 200 million people and accounts for 100,000 deaths annually. In endemic geographical areas, schistosomiasis has been implicated as an etiological agent in the pathogenesis of bladder, colorectal, and renal carcinoma largely due to Schistosoma eggs in tissues that comes with chronic infection. Several studies have also reported cases of association between Schistosoma infection and prostate cancer. The possible causal association is however poorly understood. We hypothesized in this study that infection of the prostate cells with Schistosoma spp promotes cancer. Urine samples from individuals living in Galilea, a schistosomiasis endemic community in the Ga South District of Ghana, were collected and screened for Schistosoma infection via microscopy and multiplex PCR. Soluble egg antigens (SEA) were prepared from Schistosoma egg-positive urine samples and assessed for the ability to induce cancer-like phenotypes including excessive proliferation, oxidative stress (reduced glutathione (GSH) depletion), and diminished apoptosis in cultured human prostate (PNT2) cells. Molecular analysis revealed infecting schistosome species to be S. haematobium and S. mansoni. Prostate cell proliferation was significantly induced by 12.5 µg/ml SEA (p = 0.029). Also, SEA dose-dependently depleted cellular GSH. Flow cytometric analysis and fluorescence staining revealed that SEA dose-dependently diminished apoptosis, significantly, in prostate cells. Findings of this study suggest that schistosome infection may play a role in the pathogenesis of prostate cancer. In vivo studies are however needed to confirm this association.


Assuntos
Antígenos de Helmintos/metabolismo , Carcinogênese/patologia , Óvulo/metabolismo , Próstata/patologia , Próstata/parasitologia , Schistosoma/imunologia , Animais , Apoptose , Linhagem Celular , Núcleo Celular/metabolismo , Proliferação de Células , Feminino , Glutationa/metabolismo , Humanos , Masculino , Estresse Oxidativo , Prevalência , Esquistossomose/epidemiologia , Esquistossomose/patologia , Esquistossomose/urina
15.
Molecules ; 22(4)2017 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-28346380

RESUMO

As part of our search for bioactive compounds from the Dichapetalaceae, repeated chromatographic purification of the roots of a hitherto unexamined species, Dichapetalum pallidum, led to the isolation of the newly occurring 7-hydroxydichapetalin P (1) and the known dichapetalins A (2) and X (3). Also isolated were the known compounds friedelin-2,3-lactone (4), friedelan-3-one (6), friedelan-3ß-ol (7) and pomolic (8), as well as the dipeptide aurantiamide acetate (5). The compounds were characterized by direct interpretation of their IR, 1D NMR and 2D NMR spectral data and by comparison of their physico-chemical data, including their chromatographic profiles, with the literature and authentic samples in our compound library for the genus Dichapetalum. The compounds were assayed for their anti-proliferative activities against the human T-lymphocytic leukemia (Jurkat), acute promyelocytic leukemia (HL-60) and T-lymphoblast-like leukemia (CEM) cell lines. Overall, dichapetalin X showed the strongest (3.14 µM) and broadest cytotoxic activities against all the leukemic cell lines tested, exhibiting even stronger activities than the standard compound, curcumin.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Magnoliopsida/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Células Jurkat , Estrutura Molecular , Extratos Vegetais/química , Compostos de Espiro/química , Compostos de Espiro/farmacologia
16.
Trop Med Health ; 44: 25, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27536194

RESUMO

Leishmaniasis is an infectious disease transmitted by the sand fly. It is caused by over 20 different species of Leishmania and has affected over 14 million people worldwide. One of the main forms of control of leishmaniasis is chemotherapy, but this is limited by the high cost and/or toxicity of available drugs. We previously found three novel compounds with an iridoid tetracyclic skeleton to have activity against trypanosome parasites. In this study, we determined the activity of the three anti-trypanosome compounds against Leishmania using field strain, 010, and the lab strain Leishmania hertigi. The minimum inhibitory concentration (MIC) of the compounds against 010 was determined by microscopy while the IC50 of compounds against L. hertigi was determined by fluorescence-activated cell sorting with Guava viacount analysis. We found two of the three compounds, molucidin and ML-F52, to have anti-Leishmania activity against both strains. The fluor-microscope observation with DAPI stain revealed that both Molucidin and ML-F52 induced abnormal parasites with two sets of nucleus and kinetoplast in a cell, suggesting that compounds might inhibit cytokinesis in Leishmania parasites. Molucidin and ML-F52 might be good lead compounds for the development of new anti-Leishmania chemotherapy.

17.
Antimicrob Agents Chemother ; 60(6): 3283-90, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26953191

RESUMO

Trypanosoma brucei parasites are kinetoplastid protozoa that devastate the health and economic well-being of millions of people in Africa through the disease human African trypanosomiasis (HAT). New chemotherapy has been eagerly awaited due to severe side effects and the drug resistance issues plaguing current drugs. Recently, there has been an emphasis on the use of medicinal plants worldwide. Morinda lucida Benth. is a popular medicinal plant widely distributed in Africa, and several research groups have reported on the antiprotozoal activities of this plant. In this study, we identified three novel tetracyclic iridoids, molucidin, ML-2-3, and ML-F52, from the CHCl3 fraction of M. lucida leaves, which possess activity against the GUTat 3.1 strain of T. brucei brucei The 50% inhibitory concentrations (IC50) of molucidin, ML-2-3, and ML-F52 were 1.27 µM, 3.75 µM, and 0.43 µM, respectively. ML-2-3 and ML-F52 suppressed the expression of paraflagellum rod protein subunit 2, PFR-2, and caused cell cycle alteration, which preceded apoptosis induction in the bloodstream form of Trypanosoma parasites. Novel tetracyclic iridoids may be promising lead compounds for the development of new chemotherapies for African trypanosomal infections in humans and animals.


Assuntos
Antiprotozoários/farmacologia , Iridoides/farmacologia , Morinda/química , Plantas Medicinais/química , Tripanossomicidas/farmacologia , Animais , Antiprotozoários/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Iridoides/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Tripanossomicidas/química , Trypanosoma/efeitos dos fármacos , Trypanosoma/patogenicidade , Tripanossomíase Africana/fisiopatologia
18.
Bioorg Med Chem Lett ; 25(15): 3030-3, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26048790

RESUMO

Human African trypanosomiasis (HAT), commonly known as sleeping sickness has remained a serious health problem in many African countries with thousands of new infected cases annually. Chemotherapy, which is the main form of control against HAT has been characterized lately by the viewpoints of toxicity and drug resistance issues. Recently, there have been a lot of emphases on the use of medicinal plants world-wide. Morinda lucida Benth. is one of the most popular medicinal plants widely distributed in Africa and several groups have reported on its anti-protozoa activities. In this study, we have isolated one novel tetracyclic iridoid, named as molucidin, from the CHCl3 fraction of the M. lucida leaves by bioassay-guided fractionation and purification. Molucidin was structurally elucidated by (1)H and (13)C NMR including HMQC, HMBC, H-H COSY and NOESY resulting in tetracyclic iridoid skeleton, and its absolute configuration was determined. We have further demonstrated that molucidin presented a strong anti-trypanosomal activity, indicating an IC50 value of 1.27 µM. The cytotoxicity study using human normal and cancer cell lines indicated that molucidin exhibited selectivity index (SI) against two normal fibroblasts greater than 4.73. Furthermore, structure-activity relationship (SAR) study was undertaken with molucidin and oregonin, which is identical to anti-trypanosomal active components of Alnus japonica. Overlapping analysis of the lowest energy conformation of molucidin with oregonin suggested a certain similarities of aromatic rings of both oregonin and molucidin. These results contribute to the future drug design studies for HAT.


Assuntos
Iridoides/química , Iridoides/farmacologia , Morinda/química , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Trypanosoma/efeitos dos fármacos , Animais , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Iridoides/isolamento & purificação , Modelos Moleculares , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Relação Estrutura-Atividade , Tripanossomíase Africana/tratamento farmacológico
19.
Biochem Biophys Res Commun ; 459(2): 288-293, 2015 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-25727021

RESUMO

Despite remarkable advances in combination antiretroviral therapy (cART), human immunodeficiency virus type 1 (HIV-1) infection remains incurable due to the incomplete elimination of the replication-competent virus, which persists in latent reservoirs. Strategies for targeting HIV reservoirs for eradication that involves reactivation of latent proviruses while protecting uninfected cells by cART are urgently needed for cure of HIV infection. We screened medicinal plant extracts for compounds that could reactivate the latent HIV-1 provirus and identified a procyanidin trimer C1 derived from Theobroma cacao as a potent activator of the provirus in human T cells latently infected with HIV-1. This reactivation largely depends on the NF-κB and MAPK signaling pathways because either overexpression of a super-repressor form of IκBα or pretreatment with a MEK inhibitor U0126 diminished provirus reactivation by C1. A pan-PKC inhibitor significantly blocked the phorbol ester-induced but not the C1-induced HIV-1 reactivation. Although C1-induced viral gene expression persisted for as long as 48 h post-stimulation, NF-κB-dependent transcription peaked at 12 h post-stimulation and then quickly declined, suggesting Tat-mediated self-sustainment of HIV-1 expression. These results suggest that procyanidin C1 trimer is a potential compound for reactivation of latent HIV-1 reservoirs.


Assuntos
Biflavonoides/farmacologia , Cacau/química , Catequina/farmacologia , HIV-1/efeitos dos fármacos , Proantocianidinas/farmacologia , Provírus/efeitos dos fármacos , Ativação Viral/efeitos dos fármacos , Biflavonoides/química , Biflavonoides/isolamento & purificação , Catequina/química , Catequina/isolamento & purificação , Linhagem Celular , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/genética , HIV-1/fisiologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Indóis/farmacologia , Células Jurkat , Sistema de Sinalização das MAP Quinases , Maleimidas/farmacologia , Testes de Sensibilidade Microbiana , Modelos Biológicos , NF-kappa B/metabolismo , Fitoterapia , Plantas Medicinais/química , Proantocianidinas/química , Proantocianidinas/isolamento & purificação , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Provírus/fisiologia , Latência Viral/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA