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1.
J Am Pharm Assoc (2003) ; 63(5): 1634-1642.e3, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37327997

RESUMO

BACKGROUND: The world is moving fast toward digital transformation as we live in the artificial intelligence (AI) era. The COVID-19 pandemic accelerates this movement. Chatbots were used successfully to help researchers collect data for research purposes. OBJECTIVE: To implement a chatbot on the Facebook platform to establish connections with health care professionals who had subscribed to the chatbot, provide medical and pharmaceutical educational content, and collect data for online pharmacy research projects. Facebook was chosen because it has billions of daily active users, which offers a massive potential audience for research projects. PRACTICE DESCRIPTION: The chatbot was successfully implemented on the Facebook platform following 3 consecutive steps. Firstly, the ChatPion script was installed on the Pharmind website to establish the chatbot system. Secondly, the PharmindBot application was developed on Facebook. Finally, the PharmindBot app was integrated with the chatbot system. PRACTICE INNOVATION: The chatbot responds automatically to public comments and sends subscribers private responses using AI. The chatbot collected quantitative and qualitative data with minimal costs. EVALUATION METHODS: The chatbot's auto-reply function was tested using a post published on a specific page on Facebook. Testers were asked to leave predefined keywords to test its functionality. The chatbot's ability to collect and save data was tested by asking testers to fill out an online survey within Facebook Messenger for quantitative data and answer predefined questions for qualitative data. RESULTS: The chatbot was tested on 1000 subscribers who interacted with it. Almost all testers (n = 990, 99%) obtained a successful private reply from the chatbot after sending a predefined keyword. Also, the chatbot replied privately to almost all public comments (n = 985, 98.5%) which helped to increase the organic reach and to establish a connection with the chatbot subscribers. No missing data were found when the chatbot was used to collect quantitative and qualitative data. CONCLUSIONS: The chatbot reached thousands of health care professionals and provided them with automated responses. At a low cost, the chatbot was able to gather both qualitative and quantitative data without relying on Facebook ads to reach the intended audience. The data collection was efficient and effective. Using chatbots by pharmacy and medical researchers will help do more feasible online studies using AI to advance health care research.


Assuntos
COVID-19 , Mídias Sociais , Humanos , Inteligência Artificial , Pandemias , Pessoal de Saúde
2.
PLoS One ; 18(6): e0287466, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37352311

RESUMO

BACKGROUND AND AIMS: Kratom (Mitragyna speciosa Korth.) is widely use worldwide despite its addictive potential. Although psychostimulant use has been linked to occurrence of endoplasmic reticulum (ER) stress, data is lacking on how regular kratom use affects ER stress. This case-control study first determined differences in ER stress sensor protein expression (BiP, sXBP1, ATF4, CHOP, JNK, and p-JNK) between regular kratom users and healthy controls. Second, it evaluated the association between kratom use characteristics, targeted ER stress sensor protein expression, and "kratom use disorder" diagnosed with Diagnostic and Statistical Manual for Mental Disorders 5th Edition (DSM-5) among regular kratom users. METHODS: In total, 60 regular kratom users and 50 healthy control-group participants were recruited and administered a sociodemographic and clinical characteristics questionnaire. While participants who used kratom were also administered a kratom use characteristics questionnaire. Blood samples were collected from all participants, and targeted ER stress sensor protein expression was determined via Western blot analysis. RESULTS: The study's findings revealed first that kratom users registered significantly higher protein expression in all targeted ER stress sensors compared to the control group. Second, higher protein expression of CHOP (B = 5.061, standard error [SE] = 2.547, Wald = 3.948, adjusted odds ratio [AOR] = 5.382, 95% confidence interval [CI] = 1.071 to 9.656, p = 0.047) and p-JNK (B = 5.795, SE = 2.635, Wald = 4.544, AOR = 17.025, 95% CI = 1.395 to 24.123, p = 0.017) increased the odds of kratom use disorder occurrence. Kratom use characteristics and other ER stress sensor protein expression were not associated with kratom use disorder. CONCLUSION: Regular kratom use may induce protracted ER stress, leading to the decompensation of the unfolded protein response to maintain ER homeostasis. This effect may be linked to kratom use disorder occurrence.


Assuntos
Estresse do Retículo Endoplasmático , Mitragyna , Transtornos Relacionados ao Uso de Substâncias , Resposta a Proteínas não Dobradas , Humanos , Estudos de Casos e Controles , Mitragyna/efeitos adversos , Inquéritos e Questionários , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Adulto
3.
Pulm Pharmacol Ther ; 81: 102218, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37201652

RESUMO

COPD pathogenesis is frequently associated with endoplasmic reticulum stress (ER stress) progression. Targeting the major unfolded protein response (UPR) branches in the ER stress pathway may provide pharmacotherapeutic selection strategies for treating COPD and enable relief from its symptoms. In this study, we aimed to systematically review the potential role of the ER stress inhibitors of major UPR branches (IRE1, PERK, and ATF6) in COPD-related studies and determine the current stage of knowledge in this field. The systematic review was carried out adhering to the PRISMA checklist based on published studies obtained from specific keyword searches of three databases, namely PubMed, ScienceDirect and Springer Database. The search was limited to the year 2000-2022 which includes all in vitro studies, in vivo studies and clinical trials related to the application of ER stress inhibitors toward COPD-induced models and disease. The risk of bias was evaluated using the QUIN, SYRCLE, revised Cochrane risk of bias tool for randomized trials (RoB 2.0) and NIH tool respectively. A total of 7828 articles were screened from three databases and a final total of 37 studies were included in the review. The ER stress and UPR pathways are potentially useful to prevent COPD progression and attenuate the exacerbation of COPD and related symptoms. Interestingly, the off-target effects from inhibition of the UPR pathway may be desirable or undesirable depending on context and therapeutic applications. Targeting the UPR pathway could have complex consequences as the production of ER molecules involved in folding may be impaired which could continuously provoke misfolding of proteins. Although several emerging compounds were noted to be potentially useful for targeted therapy against COPD, clinical studies have yet to be thoroughly explored.


Assuntos
Doença Pulmonar Obstrutiva Crônica , eIF-2 Quinase , Humanos , Estresse do Retículo Endoplasmático/fisiologia , Resposta a Proteínas não Dobradas , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
4.
Nat Prod Res ; 37(12): 2009-2012, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35997235

RESUMO

Cashew (Anacardium occidentale L.) leaf is traditionally used to treat skin infections. Although many flavonols have been identified from its leaf extract, their inhibitory effects on skin pathogens are not yet determined. The aims of this study were to determine the antimicrobial (against skin pathogenic microbes) and antioxidant activities of four flavonol glycosides from the crude extract and three flavonol aglycones from the hydrolyzed extract. The hydrolyzed extract was found to show higher activities than the crude extract. Myricetin showed the highest activity against all the tested bacteria and yeast with the lowest Minimum Inhibition Concentration (MIC) of 7.81 µg/mL on Corynebacterium minutissimum ATCC23348. Myricetin also exhibited good primary antioxidant activities with the effective concentration with 50% of activity (EC50) values ranged between 2.23 µg/mL and 6.40 µg/mL. The highest secondary antioxidant activity was indicated by myricetin-3-O-rhamnoside. Thus, myricetin can be considered as a bioactive compound of the hydrolyzed extract.


Assuntos
Anacardium , Flavonóis , Flavonóis/farmacologia , Antioxidantes/farmacologia , Pele , Glicosídeos , Saccharomyces cerevisiae , Extratos Vegetais/farmacologia
5.
MethodsX ; 9: 101827, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36081487

RESUMO

The data presented in this article are related to the research article entitled "Cytochrome P450 inhibition activities of non-standardized botanical products" [1], in which the possible CYP inhibitory properties of botanical products were investigated. This article describes the optimization and bioanalytical method validation of the CYP (Cytochrome P450 inhibition assay) inhibition assays, namely, phenacetin O-deethylase assay, testosterone 6ß-hydroxylase assay, felodipine dehydrogenase assay and midazolam 1'-hydroxylase assay using LC-MS/MS.

6.
J Ethnopharmacol ; 296: 115406, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35659627

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: R-tab, H-tab and E-cap botanical products are used for the treatment of various ailments. R-tab is traditionally prescribed for improving urination, H-tab is for relieving piles, hemorrhoids, fissures, and rectal inflammation and E-cap is for regulating menstruation. AIMS OF THE STUDY: To extract the botanical products and determine their potential interaction with the cytochrome P450 (CYP1A2, CYP2D6 and CYP3A4) enzymes. MATERIALS AND METHODS: R-tab, H-tab and E-cap botanical products were first extracted using solvents and analyzed using HPLC and LC-MS/MS. The effects of methanol extracts on the cytochrome induction and inhibition activities were determined using a series of in vitro assays, including multiplex RT-qPCR, CYP activity assays (P450-Glo™) and LC-MS/MS-based assays. For the CYP induction assay, omeprazole, rifampicin and dexamethasone were used as CYP1A2, CYP2D6 and CYP3A4 inducers, respectively. Ketoconazole and acetaminophen were used as positive and negative controls for the CYP3A4 inhibition assay, whereas furafylline and ketoconazole were used as positive and negative controls for the CYP1A2 inhibition assay. RESULTS: All three botanical products did not show any significant induction in CYP1A2, CYP2D6 and CYP3A4 mRNA expression. By contrast, R-tab inhibited the mRNA expression of CYP1A2 significantly from the lowest concentration of 0.01 µg/mL, while, H-tab inhibited the mRNA expression of CYP1A2 and CYP3A4 from 0.1 µg/mL. Based on the P450 Glo assays, E-cap extract inhibited the metabolic activity of CYP1A2 with an IC50 value of 37.24 µg/mL. On the other hand, R-tab, H-tab and E-cap showed inhibitory effects on the CYP3A4 enzymatic activity with IC50 values of 17.42, 18.20 and 20.60 µg/mL, respectively. However, using the LC-MS/MS-based methods, the concentration-dependent effects of R-tab and H-tab extracts on the metabolism of testosterone appeared to be more prominent, with IC50 values of 51.90 and 56.90 µg/mL as compared with the rest of the results, which were all above 100 µg/mL CONCLUSION: The CYP3A4 mRNA and enzymatic activity were moderately inhibited by R-tab and H-tab. Methanol extract of botanical products in solid dosage forms can be evaluated for their herb-drug interaction risks using in vitro assays and may provide the minimum data required for safety labeling.


Assuntos
Citocromo P-450 CYP1A2 , Citocromo P-450 CYP3A , Cromatografia Líquida , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Cetoconazol , Metanol , Microssomos Hepáticos/metabolismo , Extratos Vegetais/farmacologia , RNA Mensageiro/metabolismo , Espectrometria de Massas em Tandem
7.
J Addict Med ; 16(6): e374-e381, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35220333

RESUMO

OBJECTIVES: This study determined the association between expression of the endoplasmic reticulum (ER) stress sensor mRNA in the peripheral leukocytes and the patterns of kratom use and evaluated the correlations between the levels of the ER stress sensor mRNA and the severity of kratom dependence and kratom induced depressive symptoms among people who use kratom (PWUK). METHODS: A total of 20 PWUK and 20 age matched non-kratom using healthy controls were recruited. Data collected from PWUK included patterns of kratom use, severity of kratom dependence, and severity of depressive symptoms during abstinence from kratom. The mRNA expression of binding immunoglobulin protein ( BiP ), X-box binding protein 1, activating transcription factor 4, and C/-EBP homologous protein ( CHOP ) (major indicators of ER stress response) were analyzed using quantitative reverse transcription polymerase chain reaction in leucocyte-derived total RNA sample of the participants. RESULTS: PWUK regardless of their pattern of kratom use recorded significantly higher expression of BiP mRNA compared with controls. Expression of CHOP mRNA was only significantly higher in those who first consumed kratom at the age of 18 years and above and those who have been using kratom for longer than 6 years, compared with controls. Higher expression of BiP , ATF4 , and CHOP mRNA were significantly positive correlated with greater severity of kratom dependence. Although only higher expression of BiP and CHOP mRNA were significantly positively correlated with greater severity of depressive symptoms. CONCLUSIONS: Regular kratom consumption may activate the ER stress pathway and there may be a link between altered ER stress response and kratom dependence and kratom induced depressive symptoms.


Assuntos
Mitragyna , Humanos , Adolescente , Estresse do Retículo Endoplasmático , Extratos Vegetais , RNA Mensageiro/metabolismo
8.
Cancers (Basel) ; 13(14)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34298753

RESUMO

Lung cancers, the number one cancer killer, can be broadly divided into small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), with NSCLC being the most commonly diagnosed type. Anticancer agents for NSCLC suffer from various limitations that can be partly overcome by the application of nanomedicines. Nanoparticles is a branch within nanomedicine that can improve the delivery of anticancer drugs, whilst ensuring the stability and sufficient bioavailability following administration. There are many publications available in the literature exploring different types of nanoparticles from different materials. The effectiveness of a treatment option needs to be validated in suitable in vitro and/or in vivo models. This includes the developed nanoparticles, to prove their safety and efficacy. Many researchers have turned towards in vitro models that use normal cells or specific cells from diseased tissues. However, in cellular works, the physiological dynamics that is available in the body could not be mimicked entirely, and hence, there is still possible development of false positive or false negative results from the in vitro models. This article provides an overview of NSCLC, the different nanoparticles available to date, and in vitro evaluation of the nanoparticles. Different types of cells suitable for in vitro study and the important precautions to limit the development of false results are also extensively discussed.

9.
J Ethnopharmacol ; 278: 114294, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090914

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Anti-hyperuricemic plant parts that were selected for this study, are traditionally used to treat gout in Malaysia. Caffeic acid (a hydroxycinnamic acid), apigenin (a flavone), myricetin, quercetin and kaempferol (flavonols), were reported to act as potent xanthine oxidase inhibitors. These compounds can be found in some of the selected ethnomedicinal plants. However, there is still lack of published research works on the quantification of these inhibitors from these urate-lowering phytotherapies. AIMS OF THE STUDY: The compounds were quantified from 21 hydrolyzed extracts of the phytotherapies for gout. The activity-content contributions of the compounds to the potent extracts were determined. MATERIALS AND METHODS: The anti-hyperuricemic activities of the extracts and the compounds were determined using a xanthine oxidase inhibitory assay. Ultra-Performance Liquid Chromatography (UPLC) coupled with Photodiode Array Detector (PDA) was used to quantify the compounds in the extracts. RESULTS: The results revealed higher activity of the hydrolyzed extracts. The hydrolyzed extract of the flower bud of Syzygium aromaticum Merr. & L.M.Perry exhibited the highest activity (EC50 = 39.58 ± 0.10 µg/mL) due to the highest content of myricetin (42,297.55 ± 159.47 µg/g). The activity-content contribution of myricetin was 7.69%. Due to the highest activity of apigenin (EC50 = 3.27 ± 0.09 µg/mL), the highest contribution of this flavone (29.96%) to the hydrolyzed extract of Orthosiphon aristatus (Blume) Miq. was observed. CONCLUSION: The results revealed different contents and activities of xanthine oxidase inhibitors in the hydrolyzed extracts of anti-hyperuricemic plants can play a major role to influence the activity.


Assuntos
Supressores da Gota/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Xantina Oxidase/antagonistas & inibidores , Supressores da Gota/química , Extratos Vegetais/química , Xantina Oxidase/metabolismo
10.
J Cancer Prev ; 26(1): 1-17, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33842401

RESUMO

Patients with cancer are prone to several debilitating side effects including fatigue, insomnia, depression and cognitive disturbances. Beetroot (Beta vulgaris L.) as a health promoting functional food may be potentially beneficial in cancer. As a source of polyphenols, flavonoids, dietary nitrates and other useful nutrients, beetroot supplementation may provide a holistic means to prevent cancer and manage undesired effects associated with chemotherapy. The main aim of this narrative review is to discuss beetroot's nutrient composition, current studies on its potential utility in chemoprevention and cancer-related fatigue or treatment-related side effects such as cardiotoxicity. This review aims to provide the current status of knowledge and to identify the related research gaps in this area. The flavonoids and polyphenolic components present in abundance in beetroot support its significant antioxidant and anti-inflammatory capacities. Most in vitro and in vivo studies have shown promising results; however, the molecular mechanisms underlying chemopreventive and chemoprotective effects of beetroot have not been completely elucidated. Although recent clinical trials have shown that beetroot supplementation improves human performance, translational studies on beetroot and its functional benefits in managing fatigue or other symptoms in patients with cancer are still lacking.

11.
Obes Res Clin Pract ; 15(1): 10-18, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33371997

RESUMO

Obesity is a serious chronic disease and a public health concern in both developing and developed countries. Managing obesity has been a great challenge for both health care professionals and patients alike. Among the various diet programs aimed at promoting weight loss, the ketogenic diet, a diet high in fat and low in carbohydrates, has been at the forefront recently and its mechanism in weight loss is much debated. Activation of Sirtuin 1 or SIRT1 is able to circumvent various diseases, including metabolic syndrome and obesity and is thought to be a potentially reliable treatment target for both of them. Augmentation of SIRT1 may be carried out using dietary means such as nicotinamide adenine dinucleotide (NAD) supplementation and/or ketogenic diet. Although ketogenic diet may augment SIRT1 activation in people affected by obesity, recent studies have indicated that the relationship between SIRT1 and ketogenesis is unpredictable. The exact circumstances and mechanisms of SIRT1, NAD and ketogenesis in the clinical setting as an intervention tool in managing obesity remained uncertain. Although several recent literatures have documented significant weight-loss following ketogenic diet interventions, there were limitations with regards to duration of trial, choice and the number of trial subjects. Studies investigating the safety of ketogenic diet in the long term, beyond 46 weeks and related mechanism and pathways are still lacking and the sustainability of this diet remains to be determined. This review explores the recent progress on ketogenic diet and its relationships with SIRT1 as a tool in managing obesity and relevant clinical implications.


Assuntos
Dieta Cetogênica , Obesidade , Sirtuína 1 , Humanos , Obesidade/dietoterapia , Redução de Peso
12.
Sci Rep ; 9(1): 19757, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31874991

RESUMO

Mitragyna speciosa Korth (M. speciosa) has been widely used as a recreational product, however, there are growing concerns on the abuse potentials and toxicity of the plant. Several poisoning and fatal cases involving kratom and mitragynine have been reported but the underlying causes remain unclear. The human ether-a-go-go-related gene 1 (hERG1) encodes the pore-forming subunit underlying cardiac rapidly delayed rectifier potassium current (IKr). Pharmacological blockade of the IKr can cause acquired long QT syndrome, leading to lethal cardiac arrhythmias. This study aims to elucidate the mechanisms of mitragynine-induced inhibition on hERG1a/1b current. Electrophysiology experiments were carried out using Port-a-Patch system. Quantitative RT-PCR, Western blot analysis, immunofluorescence and co-immunoprecipitation methods were used to determine the effects of mitragynine on hERG1a/1b expression and hERG1-cytosolic chaperones interaction. Mitragynine was found to inhibit the IKr current with an IC50 value of 332.70 nM. It causes a significant reduction of the fully-glycosylated (fg) hERG1a protein expression but upregulates both core-glycosylated (cg) expression and hERG1a-Hsp90 complexes, suggesting possible impaired hERG1a trafficking. In conclusion, mitragynine inhibits hERG1a/1b current through direct channel blockade at lower concentration, but at higher concentration, it upregulates the complexation of hERG1a-Hsp90 which may be inhibitory towards channel trafficking.


Assuntos
Canais de Potássio Éter-A-Go-Go/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Complexos Multiproteicos/metabolismo , Alcaloides de Triptamina e Secologanina/farmacologia , Regulação para Cima/efeitos dos fármacos , Células HEK293 , Humanos
13.
PLoS One ; 14(1): e0210869, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30677071

RESUMO

Dengue virus Type 2 (DENV-2) is predominant serotype causing major dengue epidemics. There are a number of studies carried out to find its effective antiviral, however to date, there is still no molecule either from peptide or small molecules released as a drug. The present study aims to identify small molecules inhibitor from National Cancer Institute database through virtual screening. One of the hits, D0713 (IC50 = 62 µM) bearing thioguanine scaffold was derivatised into 21 compounds and evaluated for DENV-2 NS2B/NS3 protease inhibitory activity. Compounds 18 and 21 demonstrated the most potent activity with IC50 of 0.38 µM and 16 µM, respectively. Molecular dynamics and MM/PBSA free energy of binding calculation were conducted to study the interaction mechanism of these compounds with the protease. The free energy of binding of 18 calculated by MM/PBSA is -16.10 kcal/mol compared to the known inhibitor, panduratin A (-11.27 kcal/mol), which corroborates well with the experimental observation. Results from molecular dynamics simulations also showed that both 18 and 21 bind in the active site and stabilised by the formation of hydrogen bonds with Asn174.


Assuntos
Antivirais/química , Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Antivirais/síntese química , Domínio Catalítico , Chalconas/química , Chalconas/farmacologia , Vírus da Dengue/classificação , Vírus da Dengue/enzimologia , Estabilidade de Medicamentos , Humanos , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteases/síntese química , Serina Endopeptidases/efeitos dos fármacos , Tioguanina/química , Interface Usuário-Computador , Proteínas não Estruturais Virais/antagonistas & inibidores
14.
J Asian Nat Prod Res ; 21(8): 754-771, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30606060

RESUMO

Andrographolide, a major bioactive compound isolated from Andrographis paniculata (Burm. F.) Nees, was evaluated for its effects on the hOAT1 membrane transporter. Substrate determination and inhibition of hOAT1-mediated uptake transport assay was carried out using recombinant CHO-hOAT1 cells. The results showed that the uptake ratio of andrographolide was less than 2.0 at all concentrations tested, indicating that andrographolide is not a hOAT1 substrate. Andrographolide has no significant effects on the p-aminohippuric acid uptake and on the mRNA and protein expression of hOAT1. In conclusion, andrographolide may not pose a drug-herb interaction risk related to hOAT1.


Assuntos
Diterpenos/farmacologia , Proteína 1 Transportadora de Ânions Orgânicos/antagonistas & inibidores , Animais , Células CHO , Proliferação de Células/efeitos dos fármacos , Cricetulus , Diterpenos/farmacocinética , Interações Ervas-Drogas , Humanos , Simulação de Acoplamento Molecular , Proteína 1 Transportadora de Ânions Orgânicos/análise , Proteína 1 Transportadora de Ânions Orgânicos/química , Proteína 1 Transportadora de Ânions Orgânicos/genética , Probenecid/química , Probenecid/farmacologia , Ácido p-Aminoipúrico/farmacocinética
15.
Naunyn Schmiedebergs Arch Pharmacol ; 392(4): 481-496, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30604191

RESUMO

Mitragynine is a major component isolated from Mitragyna speciosa Korth or kratom, a medicinal plant known for its opiate-like and euphoric properties. Multiple toxicity and fatal cases involving mitragynine or kratom have been reported but the underlying causes remain unclear. P-glycoprotein (P-gp) is a multidrug transporter which modulates the pharmacokinetics of xenobiotics and plays a key role in mediating drug-drug interactions. This study investigated the effects of mitragynine on P-gp transport activity, mRNA, and protein expression in Caco-2 cells using molecular docking, bidirectional assay, RT-qPCR, Western blot analysis, and immunocytochemistry techniques, respectively. Molecular docking simulation revealed that mitragynine interacts with important residues at the nucleotide binding domain (NBD) site of the P-gp structure but not with the residues from the substrate binding site. This was consistent with subsequent experimental work as mitragynine exhibited low permeability across the cell monolayer but inhibited digoxin transport at 10 µM, similar to quinidine. The reduction of P-gp activity in vitro was further contributed by the downregulation of mRNA and protein expression of P-gp. In summary, mitragynine is likely a P-gp inhibitor in vitro but not a substrate. Hence, concurrent administration of mitragynine-containing kratom products with psychoactive drugs which are P-gp substrates may lead to clinically significant toxicity. Further clinical study to prove this point is needed.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Alcaloides de Triptamina e Secologanina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transporte Biológico , Células CACO-2 , Membrana Celular/metabolismo , Digoxina/farmacologia , Humanos , Simulação de Acoplamento Molecular , RNA Mensageiro/metabolismo
16.
Heliyon ; 4(12): e01023, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30560214

RESUMO

BACKGROUND: Dengue infection is an endemic infectious disease and it can lead to dengue fever, dengue hemorrhagic fever, and/or dengue shock syndromes. Dengue NS2B/NS3 protease complex is essential for viral replication and is a primary target for anti-dengue drug development. In this study, a NS2B/NS3 protease inhibition assay was developed using AlphaScreen® beads and was used to screen compounds for their protease inhibition activities. METHODS: The assay system utilized a known NS2B/NS3 peptide substrate, a recombinant of NS2B/NS3 protease with proprietary StrepTactin® donor and nickel chelate acceptor beads in 384-well format. RESULTS: The optimized assay to screen for NS2B/NS3 protease inhibitors was demonstrated to be potentially useful with reasonable z' factor, coefficient variance and signal to background ratio. However, screening of synthesized thioguanine derivatives using the optimized AlphaScreen® assay revealed weak NS2B/NS3 inhibition activities. CONCLUSION: The AlphaScreen® assay to screen for NS2B/NS3 protease inhibitors is potentially applicable for high throughput screening.

17.
Data Brief ; 14: 584-591, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28879216

RESUMO

The data presented in this article are related to the research article entitled "The effects of deoxyelephantopin on the cardiac delayed rectifier potassium channel current (IKr) and human ether-a-go-go-related gene (hERG) expression" (Y.F. Teah, M.A. Abduraman, A. Amanah, M.I. Adenan, S.F. Sulaiman, M.L. Tan) [1], which the possible hERG blocking properties of deoxyelephantopin were investigated. This article describes the construction of human embryonic kidney 293 (HEK293) cells overexpressing HERG potassium channel and verification of the presence of hERG mRNA and protein expression in this recombinant cell line.

18.
Food Chem Toxicol ; 107(Pt A): 293-301, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28689918

RESUMO

Elephantopus scaber Linn and its major bioactive component, deoxyelephantopin are known for their medicinal properties and are often reported to have various cytotoxic and antitumor activities. This plant is widely used as folk medicine for a plethora of indications although its safety profile remains unknown. Human ether-a-go-go-related gene (hERG) encodes the cardiac IKr current which is a determinant of the duration of ventricular action potentials and QT interval. The hERG potassium channel is an important antitarget in cardiotoxicity evaluation. This study investigated the effects of deoxyelephantopin on the current, mRNA and protein expression of hERG channel in hERG-transfected HEK293 cells. The hERG tail currents following depolarization pulses were insignificantly affected by deoxyelephantopin in the transfected cell line. Current reduction was less than 40% as compared with baseline at the highest concentration of 50 µM. The results were consistent with the molecular docking simulation and hERG surface protein expression. Interestingly, it does not affect the hERG expression at both transcriptional and translational level at most concentrations, although higher concentration at 10 µM caused protein accumulation. In conclusion, deoxyelephantopin is unlikely a clinically significant hERG channel and Ikr blocker.


Assuntos
Asteraceae/química , Canais de Potássio de Retificação Tardia/genética , Canais de Potássio Éter-A-Go-Go/genética , Lactonas/farmacologia , Miocárdio/metabolismo , Extratos Vegetais/farmacologia , Potássio/metabolismo , Sesquiterpenos/farmacologia , Canais de Potássio de Retificação Tardia/metabolismo , Canais de Potássio Éter-A-Go-Go/metabolismo , Células HEK293 , Coração/efeitos dos fármacos , Humanos
19.
Toxicol Appl Pharmacol ; 305: 22-39, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27260674

RESUMO

Mitragyna speciosa Korth is known for its euphoric properties and is frequently used for recreational purposes. Several poisoning and fatal cases involving mitragynine have been reported but the underlying causes remain unclear. Human ether-a-go-go-related gene (hERG) encodes the cardiac IKr current which is a determinant of the duration of ventricular action potentials and QT interval. On the other hand, IK1, a Kir current mediated by Kir2.1 channel and IKACh, a receptor-activated Kir current mediated by GIRK channel are also known to be important in maintaining the cardiac function. This study investigated the effects of mitragynine on the current, mRNA and protein expression of hERG channel in hERG-transfected HEK293 cells and Xenopus oocytes. The effects on Kir2.1 and GIRK channels currents were also determined in the oocytes. The hERG tail currents following depolarization pulses were inhibited by mitragynine with an IC50 value of 1.62µM and 1.15µM in the transfected cell line and Xenopus oocytes, respectively. The S6 point mutations of Y652A and F656A attenuated the inhibitor effects of mitragynine, indicating that mitragynine interacts with these high affinity drug-binding sites in the hERG channel pore cavity which was consistent with the molecular docking simulation. Interestingly, mitragynine does not affect the hERG expression at the transcriptional level but inhibits the protein expression. Mitragynine is also found to inhibit IKACh current with an IC50 value of 3.32µM but has no significant effects on IK1. Blocking of both hERG and GIRK channels may cause additive cardiotoxicity risks.


Assuntos
Canal de Potássio ERG1/fisiologia , Bloqueadores dos Canais de Potássio/farmacologia , Alcaloides de Triptamina e Secologanina/farmacologia , Animais , Alcaloides Diterpenos , Canal de Potássio ERG1/genética , Canal de Potássio ERG1/metabolismo , Células HEK293 , Coração/fisiologia , Humanos , Potenciais da Membrana/efeitos dos fármacos , Oócitos/metabolismo , RNA Mensageiro/metabolismo , Xenopus
20.
Data Brief ; 7: 1506-10, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27182548

RESUMO

The data presented in this article are related to the research article entitled "14-deoxy-11,12-didehydroandrographolide induces DDIT3-dependent endoplasmic reticulum stress-mediated autophagy in T-47D breast carcinoma cells", which the mechanistic toxicology properties of 14-deoxy-11,12-didehydroandrographolide (14-DDA) were investigated (Tan et al., 2016 [1]). This article describes the derivation of cytotoxic parameters of 14-DDA, cell viability data after double transfection and DDIT3 silencing in T-47D cells.

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