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1.
Xenobiotica ; 45(3): 218-29, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25377539

RESUMEN

1.This study investigated the mechanism underlying Echinacea-mediated induction of CYP1A2, CYP3A4 and MDR1 in terms of human pregnane X receptor (PXR) activation. 2.Crude extracts and fractions of Echinacea purpurea were tested for PXR activation in HepG2 cells by a reporter gene assay. Quantitative real-time PCR was carried out to determine their effects on CYP1A2 and CYP3A4 mRNA expressions. Capsules and fractions were risk ranked as high, intermediate and remote risk of drug-metabolizing enzymes induction based on EC50 values determined for respective CYPs. 3. Fractions F1, F2 and capsule (2660) strongly activated PXR with 5-, 4- and 3.5-fold increase in activity, respectively. Echinacea preparations potentiated up-regulation of CYP1A2, CYP3A4 and MDR1 via PXR activation. 4.Thus E. purpurea preparations cause herb-drug interaction by up-regulating CYP1A2, CYP3A4 and P-gp via PXR activation.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP3A/genética , Echinacea/química , Extractos Vegetales/farmacología , Receptores de Esteroides/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Biocatálisis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP3A/metabolismo , Genes Reporteros , Células Hep G2 , Interacciones de Hierba-Droga , Humanos , Luciferasas/metabolismo , Receptor X de Pregnano , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Tiempo , Activación Transcripcional/efectos de los fármacos , Activación Transcripcional/genética
2.
Reprod Biol Endocrinol ; 12: 34, 2014 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-24885899

RESUMEN

BACKGROUND: Obesity appears to be associated with male reproductive dysfunction and infertility, although this has been inconsistent and inconclusive. Insulin and leptin are known mediators and modulators of the hypothalamus-pituitary-testes axis, contributing to the regulation of male reproductive potential and overall wellbeing. These hormones are also present in semen influencing sperm functions. Although abdominal obesity is closely associated with insulin resistance (hyperinsulinaemia), hyperleptinaemia and glucose dysfunction, changes in seminal plasma concentrations of insulin, leptin and glucose in obese males has not previously been investigated. METHODS: This small case controlled study assessed serum and seminal concentrations of insulin, leptin and glucose in obese (BMI > =30; n = 23) and non-obese (BMI < 30; n = 19) males. Following a detailed medical history and examination, participants meeting the inclusion criteria were entered for data analysis. Body parameters such as BMI, waist and hip circumference and the waist hip ratio were measured. Serum and semen samples were collected and assayed for insulin, leptin and glucose. Semen samples also underwent a standard semen analysis, with sperm mitochondrial membrane potential (MMP) and DNA fragmentation (DF). RESULTS: Obesity was associated with increased serum and seminal insulin and leptin, with no significant difference in seminal glucose. Serum and seminal concentrations of insulin and leptin were positively correlated. Furthermore, obesity was associated with decreased sperm concentration, sperm vitality and increased MMP and DF, with a non-significant impact on motility and morphology. CONCLUSIONS: Hyperinsulinaemia and hyperleptinaemia are associated with increased seminal insulin and leptin concentrations, which may negatively impact male reproductive function in obesity. Insulin was also found to be highly concentrated in the seminal plasma of both groups. This data will contribute to the contradictive information available in the literature on the impact of obesity and male reproduction.


Asunto(s)
Infertilidad Masculina/etiología , Insulina/metabolismo , Leptina/metabolismo , Obesidad/fisiopatología , Semen/metabolismo , Regulación hacia Arriba , Adulto , Índice de Masa Corporal , Estudios de Casos y Controles , Estudios de Cohortes , Fragmentación del ADN , Humanos , Hiperinsulinismo/etiología , Insulina/sangre , Leptina/sangre , Masculino , Potencial de la Membrana Mitocondrial , Persona de Mediana Edad , Obesidad/sangre , Obesidad/metabolismo , Proyectos Piloto , Análisis de Semen , Sudáfrica , Adulto Joven
3.
Drug Metab Dispos ; 41(2): 488-97, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23209194

RESUMEN

In Africa, Sutherlandia frutescens is a popular medicinal herb widely consumed by people living with human immunodeficiency virus/AIDS. Concomitant use with antiretroviral drugs has generated concerns of herb-drug interaction (HDI). This study investigated the inhibitory effects of the crude extracts of S. frutescens on the major cytochrome P450 isozymes with the use of pooled human liver microsomes. Its effect on the metabolic clearance of midazolam using cryopreserved hepatocytes was also monitored. The potential of S. frutescens to inhibit human ATP-binding cassette transporters (P-gp and BCRP) and the human organic anion transporting polypeptide (OATP1B1 and OATP1B3) activity was assessed using cell lines overexpressing the transporter proteins. S. frutescens showed inhibitory potency for CYP1A2 (IC(50) = 41.0 µg/ml), CYP2A6 (IC(50) = 160 µg/ml), CYP2B6 (IC(50) = 20.0 µg/ml), CYP2C8 (IC(50) = 22.4 µg/ml), CYP2C9 (IC(50) = 23.0 µg/ml), CYP2C19 (IC(50) = 35.9 µg/ml), and CYP3A4/5 (IC(50) = 17.5 µg/ml [with midazolam1'-hydroxylation]; IC(50) = 28.3 µg/ml [with testosterone 6ß-hydroxylation]). Time-dependent (irreversible) inhibition by S. frutescens was observed for CYP3A4/5 (K(I) = 296 µg/ml, k(inact) = 0.063 min(-1)) under the conditions of this study. S. frutescens also delays the production of midazolam metabolites in the hepatocytes, decreasing its clearance by 40%. Furthermore, S. frutescens inhibited P-gp (IC(50) = 324.8 µg/ml), OATP1B1 (IC(50) = 10.4 µg/ml), and OATP1B3 (IC(50) = 6.6 µg/ml). The result indicates the potential for HDI between S. frutescens and the substrates of the affected enzymes, if sufficient in vivo concentration of the extract is attained.


Asunto(s)
Inhibidores Enzimáticos del Citocromo P-450 , Inhibidores Enzimáticos/farmacología , Fabaceae/química , Hepatocitos/efectos de los fármacos , Interacciones de Hierba-Droga , Moduladores del Transporte de Membrana/farmacología , Proteínas de Transporte de Membrana/efectos de los fármacos , Preparaciones de Plantas/farmacología , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Transporte Biológico , Biotransformación , Sistema Enzimático del Citocromo P-450/metabolismo , Perros , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/aislamiento & purificación , Femenino , Células HEK293 , Hepatocitos/enzimología , Humanos , Hidroxilación , Isoenzimas , Cinética , Células LLC-PK1 , Transportador 1 de Anión Orgánico Específico del Hígado , Células de Riñón Canino Madin Darby , Masculino , Moduladores del Transporte de Membrana/aislamiento & purificación , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Midazolam/metabolismo , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/metabolismo , Transportadores de Anión Orgánico/antagonistas & inhibidores , Transportadores de Anión Orgánico/metabolismo , Transportadores de Anión Orgánico Sodio-Independiente/antagonistas & inhibidores , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo , Hojas de la Planta , Preparaciones de Plantas/aislamiento & purificación , Plantas Medicinales , Miembro 1B3 de la Familia de los Transportadores de Solutos de Aniones Orgánicos , Especificidad por Sustrato , Porcinos , Testosterona/metabolismo , Transfección
4.
Pharm Biol ; 51(12): 1499-507, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23844611

RESUMEN

CONTEXT: Aqueous decoction of Hypoxis hemerocallidea Fisch. & C.A. Mey. (Hypoxidaceae) (Hypoxis) is widely consumed in Southern Africa by people living with HIV/AIDS, some of whom are on ARV and other medications. OBJECTIVE: The aim of this study was to investigate the potential of the crude aqueous extracts of Hypoxis to inhibit major forms of CYP450 and transport proteins. MATERIALS AND METHODS: Corms of Hypoxis were water-extracted and incubated (in graded concentrations: 1-100 µg/mL) with human liver microsomes (20 min) to monitor the effects on phenacetin O-deethylation, coumarin 7-hydroxylation, bupropion hydroxylation, paclitaxel 6α-hydroxylation, diclofenac 4'-hydroxylation, S-mephenytoin 4'-hydroxylation, bufuralol 1'-hydroxylation, chlorzoxazone 6-hydroxylation, midazolam 1'-hydroxylation and testosterone 6ß-hydroxylation as markers for the metabolic activities of CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1 and 3A4/5, respectively. The generation of metabolites were monitored and quantified with the aid of LC-MS/MS. The potential of the extracts to inhibit human ATP-binding cassette transporter activity was assessed using recombinant MDCKII and LLC-PK1 cells over-expressing human breast cancer resistant protein and human P-glycoprotein , respectively (with Ko143 and cyclosporin A as positive controls). Similar assessment was performed with human organic anion transporting polypeptide (OATP1B1 and OATP1B3) using recombinant HEK293 cells over-expressing OATP1B1 and OATP1B3, respectively (with rifamycin and 10 µM atorvastatin as positive controls). RESULTS: Extracts of Hypoxis inhibited the production of the metabolites of the substrates of the following enzymes (as compared to controls) with the indicated IC50 values (µg/mL): CYP1A2 (120.6), CYP2A6 (210.8), CYP2B6 (98.5), CYP2C8 (195.2), CYP2C9 (156) and CYP3A4/5 (185.4). The inhibition of the uptake activity of OATP1B1 and OATP1B3 were also observed with IC50 values of 93.4 and 244.8 µg/mL, respectively. DISCUSSION: Extract concentrations higher than the estimated IC50 values are achievable in the gastrointestinal tract when traditional doses of Hypoxis are considered. This may have profound effects on presystemic metabolism of the drug substrates. If absorbed, systemic inhibition of metabolic enzymes/transporters by Hypoxis may be expected. CONCLUSION: The result suggests that there is the potential for HDI between Hypoxis and the substrates of the affected enzymes/transporters, if sufficient in vivo concentration of Hypoxis extracts is attained.


Asunto(s)
Interacciones de Hierba-Droga , Hypoxis/química , Microsomas Hepáticos/efectos de los fármacos , Preparaciones Farmacéuticas , Extractos Vegetales/farmacología , Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Animales , Inhibidores Enzimáticos del Citocromo P-450 , Perros , Células HEK293 , Humanos , Técnicas In Vitro , Células LLC-PK1 , Células de Riñón Canino Madin Darby , Medicinas Tradicionales Africanas , Microsomas Hepáticos/enzimología , Extractos Vegetales/aislamiento & purificación , Especificidad por Sustrato , Porcinos
5.
JBRA Assist Reprod ; 27(2): 144-146, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37348006

RESUMEN

Endometriosis is a chronic inflammatory condition affecting up to 10% of women of reproductive age and this, depending on its severity, very often leads to infertility. New research has shed light on the role of underlying endometritis due to the presence of inflammatory, non-oestrogen metabolising microbiome at the mucosal interface and this in turn leads to the activation of aggressive, non-tolerant immune cells in the endometrium. These immune cells require the presence of tolerance-inducing commensals such as Lactobacilli so as to allow the implantation of the fertilised egg. New therapies should be holistic and address both the dysbiosis as well as immune abnormalities. Routine immune monitoring of the immune cells derived from the endometrium and/or microbial profiling should recommended to better predict assisted reproduction outcomes in these couples.


Asunto(s)
Endometriosis , Endometritis , Infertilidad Femenina , Infertilidad , Femenino , Humanos , Endometriosis/complicaciones , Endometritis/complicaciones , Infertilidad/etiología , Implantación del Embrión/fisiología , Endometrio , Infertilidad Femenina/etiología
6.
J Ethnopharmacol ; 270: 113766, 2021 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-33395575

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Withania somnifera (L.) Dunal (Solanaceae) is a traditional herb, used in African indigenous systems of medicine for the treatment of various diseases (including HIV/AIDS and tuberculosis). The relevance of clinically significant interactions of Withania with ARVs and anti-TB drugs needs to be investigated. AIM OF THE STUDY: This study evaluated the effects of its roots on cytochromes P450 (CYPs) 2B6, 3A4, and rifampicin metabolism pathway, using methanol, ethanol, aqueous, and ethyl acetate solvent extractions. MATERIALS AND METHODS: The extracts were tested on human liver microsomes (HLM) for CYP inhibition, mRNA expression in HepG2 cells for CYP induction. Biochemical qualitative tests and LC-MS/MS methodology were used to determine active phytoconstituents. RESULTS: The methanolic and ethyl acetate extracts inhibited CYP2B6 with IC50s 79.16 and 57.96 µg/ml respectively, while none of the extracts had any effect on rifampicin metabolism or showed time-dependant inhibition (TDI). All extracts were moderate inducers of CYP3A4; the aqueous extract exhibited 38%-fold shift induction of CYP3A4 compared to the control. The methanolic extract had the lowest CTC50 (50% of cytotoxicity inhibition) (67.13 ± 0.83 µg/ml). LC-MS/MS-PDA full scans were consistent with the presence of flavone salvigenin (m/z 327), alkaloid isopelletierine (m/z 133), steroidal lactone 2,3-dihydrowithaferin-A (m/z 472), and other withanolides including withaperuvin I (m/z 533), withaferin derivative (m/z 567), some of these compounds likely being responsible for the observed CYP2B6 inhibition and CYP3A4 induction. The putative gastrointestinal tract (GIT) concentration for the active extracts was 1800 µg/ml and the hepatic circulation concentrations were estimated at about 220 µg/ml and 13.5 µg/ml for the methanolic and ethyl acetate extracts, respectively. The extrapolated in vivo percentage of inhibition was at 85% for the methanolic extract against CYP2B6. CONCLUSIONS: The findings reported in this study suggest that W. somnifera extracts have the potential of causing clinically significant herb-drug interactions (HDI) as moderate inducer of CYP3A4 and inhibitor of CYP2B6 metabolism pathway (methanol and ethyl acetate extracts).


Asunto(s)
Citocromo P-450 CYP2B6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Esterasas/metabolismo , Microsomas Hepáticos/enzimología , Extractos Vegetales/farmacología , Withania/química , Citocromo P-450 CYP2B6/genética , Inhibidores del Citocromo P-450 CYP2B6/farmacología , Citocromo P-450 CYP3A/genética , Inductores del Citocromo P-450 CYP3A/farmacología , Células Hep G2 , Interacciones de Hierba-Droga , Humanos , Concentración 50 Inhibidora , Medicinas Tradicionales Africanas , Microsomas Hepáticos/efectos de los fármacos , Raíces de Plantas/química , Plantas Medicinales/química , Rifampin/metabolismo
7.
Bioanalysis ; 13(15): 1183-1193, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34114884

RESUMEN

Aim: Serological assays for the detection of anti-SARS coronavirus-2 (SARS-CoV-2) antibodies are essential to the response to the global pandemic. A ligand binding-based serological assay was validated for the semiquantitative detection of IgG, IgM, IgA and neutralizing antibodies (nAb) against SARS-CoV-2 in serum. Results: The assay demonstrated high levels of diagnostic specificity and sensitivity (85-99% for all analytes). Serum IgG, IgM, IgA and nAb correlated positively (R2 = 0.937, R2 = 0.839, R2 = 0.939 and R2 = 0.501, p < 0.001, respectively) with those measured in dried blood spot samples collected using the hemaPEN® microsampling device (Trajan Scientific and Medical, Victoria, Australia). In vitro SARS-CoV-2 pseudotype neutralization correlated positively with the solid phase nAb signals in convalescent donors (R2 = 0.458, p < 0.05). Conclusion: The assay is applicable in efficacy studies, infection monitoring and postmarketing surveillance following vaccine rollout.


Asunto(s)
COVID-19/sangre , Pruebas con Sangre Seca/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , SARS-CoV-2/patogenicidad , Bioensayo , Voluntarios Sanos , Humanos , Reproducibilidad de los Resultados
8.
AIMS Microbiol ; 7(3): 320-335, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34708175

RESUMEN

The objective of this study was to elucidate the proteomic mechanisms of drug resistance in HIV-infected African patients. Cell membrane fractions from forty oral Candida isolates isolated from African HIV-positive patients were analysed using HPLC-MS with the aim of identifying proteins associated with their pathogenicity and drug resistance. Heat shock proteins that mediate the fungicidal activity of salivary peptides were found in all tested Candida fractions, with pH-responsive proteins associated with increased pathogenicity only being present in the three most commonly isolated species. ABC multidrug transporter efflux pumps and estrogen binding proteins were only found in C. albicans fractions, while ergosterol biosynthesis proteins were identified in four species. The combination of various adherence, invasion, upregulation and efflux pump mechanisms appear to be instrumental for the Candida host colonization and drug resistance emergence in HIV-infected individuals.

9.
Front Pharmacol ; 11: 517, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32425779

RESUMEN

Ocimum basilicum L. or basilicum is a common culinary herb, used as a traditional medicine for various medical conditions including HIV/AIDS and tuberculosis, in Africa. The objective of this study was to evaluate the effect of methanol, ethanol, aqueous and ethyl acetate extracts of the dried leaves and inflorescence of O. basilicum, on the activity of cytochrome P450 enzymes (CYPs) CYP2B6 and 3A4, as well as esterase-mediated metabolism of rifampicin to 25-O-desacetyl rifampicin (25ODESRIF). Human liver microsomes (HLM) were used to evaluate inhibition and CYP2B6/3A4 mRNA expression HepG2 assays were used to measure induction. Furthermore, the phytoconstituents likely involved in causing the observed effect were analyzed using biochemical tests and LC-MS. The aqueous and methanolic extracts showed reversible and time-dependent inhibition (TDI) of CYP2B6 with TDI-IC50s 33.35 µg/ml (IC50 shift-fold >1.5) and 4.93 µg/ml (IC50 shift-fold >7) respectively, while the methanolic and ethanolic extracts inhibited 25ODESRIF formation (IC50s 31 µg/ml, 8.94 µg/ml). In HepG2 assays, the methanolic and ethanolic extracts moderately induced CYP2B6, 3A4 mRNA with 38%-, 28%-fold shift, and 22%-, 44%-fold shift respectively. LC-MS full scans identified phenols rosmarinic acid [m/z 359 (M-H)-, approximately 2298 mg/L in aqueous extract] and caftaric acid along with flavones salvigenin [m/z 329 (M+H)+, approximately 1855 mg/L in ethanolic extract], eupatorin [m/z 345 (M+H)+, 668.772 mg/L in ethanolic extract], rutin [m/z 609 (M-H)-] and isoquercetin [m/z 463 (M-H)-] and other compounds-linalool [m/z 153 (M-H)-], hydroxyjasmonic acid [m/z 225 (M-H)-], eucommiol [m/z 187 (M-H)-] and trihydroxy octadecenoic acid [m/z 329 (M-H)-, 530 mg/L in ethanolic extract]. The putative gastrointestinal tract (GIT) concentration for all extracts was calculated as 2,400 µg/ml and hepatic circulation concentrations were estimated at 805.68 µg/ml for the aqueous extract, and 226.56 µg/ml for methanolic extract. Based on the putative GIT concentration, estimated hepatic circulation concentration [I] and inhibition constant Ki, the predicted percentile of inhibition in vivo was highest for the aqueous extract on CYP2B6 (96.7%). The observations indicated that O. basilicum extracts may have the potential to cause clinically relevant herb-drug interactions (HDI) with CYP2B6 and rifampicin metabolism in vivo, if sufficient hepatic concentrations are reached in humans.

10.
AAPS PharmSciTech ; 10(1): 270-5, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19280345

RESUMEN

The pharmaceutical industry is in need of rapid and accurate methods to screen new drug leads for intestinal permeability potential in the early stages of drug discovery. Excised human jejunal mucosa was used to investigate the permeability of the small intestine to four oral drugs, using a flow-through diffusion system. The four drugs were selected as representative model compounds of drug classes 1 and 3 according to the biopharmaceutics classification system (BCS). The drugs selected were zidovudine, propranolol HCl, didanosine, and enalapril maleate. Permeability values from our in vitro diffusion model were compared with the BCS permeability classification and in vivo and in vitro gastrointestinal drug permeability. The flux rates of the four drugs were influenced by the length of the experiment. Both class 1 drugs showed a significantly higher mean flux rate between 2 and 6 h across the jejunal mucosa compared to the class 3 drugs. The results are therefore in line with the drugs' BCS classification. The results of this study show that the permeability values of jejunal mucosa obtained with the flow-through diffusion system are good predictors of the selected BCS class 1 and 3 drugs' permeation, and it concurred with other in vitro and in vivo studies.


Asunto(s)
Didanosina/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Enalapril/metabolismo , Absorción Intestinal , Mucosa Intestinal/metabolismo , Yeyuno/metabolismo , Propranolol/metabolismo , Zidovudina/metabolismo , Administración Oral , Adulto , Didanosina/administración & dosificación , Difusión , Enalapril/administración & dosificación , Femenino , Humanos , Técnicas In Vitro , Cinética , Masculino , Persona de Mediana Edad , Permeabilidad , Propranolol/administración & dosificación , Reproducibilidad de los Resultados , Solubilidad , Zidovudina/administración & dosificación
11.
South Afr J HIV Med ; 19(1): 809, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30473875

RESUMEN

BACKGROUND: Altered immune mechanisms play a critical role in the pathogenesis of non-Hodgkin's lymphoma (NHL). HIV-1 (HIV) infection is associated with a state of excessive T-cell activation, which can lead to increased T-cell turnover and lymph node fibrosis. OBJECTIVES: This study aimed to determine the serum levels of circulating B-cell activation markers, and the expression of T-cell activation and regulatory markers in HIV-positive NHL patients. METHOD: The serum levels of circulating soluble(s) sCD20, sCD23, sCD27, sCD30 and sCD44 molecules, all of which are biomarkers of B-cell activation, were determined by enzyme-linked immunosorbent assays (ELISA), while biomarkers of T-cell activation (CD8+CD38+) and regulation (FoxP3) were determined by flow cytometry in 141 subjects who were divided into five groups: Combination antiretroviral therapy (ART)-naïve HIV-positive patients; ART-treated HIV-positive patients; HIV-negative NHL patients; HIV-positive NHL patients on ART; and healthy controls. RESULTS: HIV-positive NHL patients had significantly higher serum levels of sCD20, sCD23, sCD30 and sCD44 than HIV-negative NHL patients, while all five biomarkers were significantly elevated in HIV-positive NHL patients when compared with ART-treated HIV-positive patients. HIV-positive NHL patients had higher CD8+CD38+ and lower FoxP3 expression than HIV-negative NHL and ART-treated HIV-positive patients. CONCLUSION: B-cell activation is increased in HIV-positive NHL patients and is associated with reduced regulatory T-cell populations and increased CD8+ T-cell activation.

12.
J Music Ther ; 44(2): 156-68, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17484523

RESUMEN

The purpose of this study was to determine the effect of Bach's Magnificat on emotions, immune, and endocrine parameters in patients of specific infectious lung conditions. Participants (N = 40; 9 men & 31 women) ranging in age from 40 to 75 participated in the study. Patients were randomly allocated to an experimental and control group. During a 3-day period the experimental group received physiotherapy with the selected music, while the control group only received physiotherapy. ANOVA statistics indicate significant changes in the following parameters: POMS-scale, CD4+:CD8+ ratio, cortisol, and cortisol:DHEA ratio. The intervention of music demonstrates communication between the mind and body.


Asunto(s)
Afecto , Bronquitis/metabolismo , Bronquitis/terapia , Musicoterapia/métodos , Neumonía Bacteriana/metabolismo , Neumonía Bacteriana/terapia , Adulto , Anciano , Ejercicios Respiratorios , Bronquitis/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Terapia Combinada , Deshidroepiandrosterona/sangre , Femenino , Humanos , Hidrocortisona/sangre , Masculino , Persona de Mediana Edad , Nebulizadores y Vaporizadores , Neumonía Bacteriana/inmunología , Encuestas y Cuestionarios , Resultado del Tratamiento
13.
Am J Reprod Immunol ; 76(2): 155-63, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27334450

RESUMEN

PROBLEM: The impact of metabolic syndrome (MetS) associated systemic inflammation on the male reproductive tract requires further investigation. METHOD OF STUDY: A cross-sectional case-controlled study design consisting of a control group (n=32) and a MetS (n=42) group was used. Variables include MetS diagnostic criterion, serum C-Reactive Protein (CRP), routine semen analysis, spermatozoa mitochondrial membrane potential (MMP) and DNA fragmentation (DF), as well as TNF-α, IL-1ß, IL6 and IL8 concentrations in serum and semen. RESULTS: Serum and seminal levels of TNF-α, IL-1ß, IL6 and IL8 were all significantly increased in the MetS group. Ejaculation volume, sperm concentration, total sperm count, progressive and total motility and vitality were significantly decreased and sperm with abnormal MMP and DF were increased in the MetS group. CONCLUSION: The results suggest that MetS is associated with decreased fertility parameters in males, as well as local reproductive tract inflammation, in the absence of leukocytospermia.


Asunto(s)
Proteína C-Reactiva/inmunología , Citocinas/inmunología , Fertilidad/inmunología , Síndrome Metabólico/inmunología , Semen/inmunología , Adulto , Anciano , Estudios de Casos y Controles , Fragmentación del ADN , Humanos , Masculino , Potencial de la Membrana Mitocondrial/inmunología , Persona de Mediana Edad , Recuento de Espermatozoides , Espermatozoides/inmunología
14.
Drug Metab Lett ; 9(1): 48-62, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25600201

RESUMEN

Kalanchoe crenata popularly known as "dog's liver" is used in most African countries for the treatment of chronic diseases such as diabetes, asthma and HIV/AIDS related infections. The evaluation of K. crenata for herb-drug interactions has not been reported. This study therefore aims to evaluate the risk of K. crenata for herb-drug interaction in vitro. Crude methanol and fractions of K. crenata were incubated and preincubated with recombinant human CYP2C19 and CYP3A4. Comparative studies were conducted in both human liver microsomes and recombinant human CYP to ascertain the inhibition profile of the crude extract and the various fractions. The cocktail approach of recombinant human CYPs was conducted to confirm the inhibition potential of the fractions in the presence of other CYPs. The results showed significant time-dependent inhibition of tested samples on CYP3A4 with crude methanol (39KC), fractions 45A, 45B and 45D given IC50 fold decrease of 3.29, 2.26, 1.91 and 1.49, respective. Time dependent kinetic assessment of 39KC and 45D showed KI and kinact values for 39KC as 1.77 µg/mL and 0.091 min(-1) while that of 45D were 6.45 µg/mL and 0.024 min(-1), respectively. Determination of kinact based on IC50 calculations yielded 0.015 and 0.04 min(-1) for 39KC and 45D, respectively. Cocktail approach exhibited fold decreases in IC50 for all test fractions on CYP3A4 within the ranges of 2.10 - 4.10. At least one phytoconstituent in the crude methanol extract of Kalanchoe crenata is a reversible and time-dependent inhibitor of CYP3A4.


Asunto(s)
Inhibidores del Citocromo P-450 CYP2C19/farmacología , Citocromo P-450 CYP2C19/metabolismo , Inhibidores del Citocromo P-450 CYP3A/farmacología , Citocromo P-450 CYP3A/metabolismo , Kalanchoe , Hígado/efectos de los fármacos , Extractos Vegetales/farmacología , Inhibidores del Citocromo P-450 CYP2C19/aislamiento & purificación , Inhibidores del Citocromo P-450 CYP3A/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Hepatocitos/efectos de los fármacos , Hepatocitos/enzimología , Interacciones de Hierba-Droga , Humanos , Kalanchoe/química , Cinética , Hígado/enzimología , Metanol/química , Microsomas Hepáticos/enzimología , Modelos Biológicos , NADP/metabolismo , Extractos Vegetales/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Medición de Riesgo , Solventes/química , Testosterona/metabolismo
15.
Drug Discov Today ; 7(14): 775-8, 2002 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-12547034

RESUMEN

Since the discovery of glucocorticoids, we have had a single strategy for manipulating the immune system in cases of destructive diseases mediated by uncontrolled immune responses. However, long-term use of immunosuppressive drugs can lead to the threat of opportunistic infections and malignancies. As we learn more about regulatory subsets of T lymphocytes and their cytokine profiles, the thrust has been on developing new ligands that ultimately give us more site-specific control. Our group has developed a patented mixture of plant sterols and sterolins that has anti-inflammatory properties and profound immune modulating effects on subsets of CD4+ T cells. We have tested this mixture in several clinical entities and we believe that it has wide applications in reverting immune abnormalities.


Asunto(s)
Enfermedades del Sistema Inmune/tratamiento farmacológico , Esteroles/uso terapéutico , Diseño de Fármacos , Humanos , Lipoproteínas/uso terapéutico , Fitosteroles/uso terapéutico , Fitoterapia , Relación Estructura-Actividad
16.
Artículo en Inglés | MEDLINE | ID: mdl-25392581

RESUMEN

BACKGROUND: Studies have suggested an increasing practice of concurrent herb-drug consumption. One of the major clinical risks of such concomitant herb-drug use is pharmacokinetic herb-drug interaction (HDI). This is brought about by the ability of phytochemicals to inhibit or induce the activity of metabolic enzymes. The aim of this study was to investigate the potential of the crude aqueous extracts of three popular medicinal herbs used in South Africa to inhibit major cytochrome P450 (CYP) enzymes. MATERIALS AND METHODS: The extracts of Bowiea volubilis, Spirostachys africana and Tulbaghia violacea were incubated with human liver microsomes (HLM) to monitor the phenacetin O-deethylation, diclofenac 4'-hydroxylation, S-mephenytoin 4'-hydroxylation and testosterone 6ß-hydroxylation as respective probe reactions for CYP1A2, CYP2C9, CYP2C19 and CYP3A4. The inhibitory activity, where observed, was profiled against the extract concentration. RESULTS: Extracts of Bowiea volubilis inhibited the metabolic activity of CYP1A2 and CYP3A4 with IC50 values of 92.3 ± 5.5 µg/mL and 8.1 ± 0.6 µg/mL respectively. Similar observation with Spirostachys africana showed inhibitory activity against CYP1A2 and CYP3A4 with respective IC50 values of 14.3 ± 0.6 µg/mL and 47.4 ± 2.4 µg/mL. Tulbaghia violacea demonstrated relatively weak inhibitory activity against CYP1A2 (767.4 ± 10.8 µg/mL) and CYP2C9 (921 ± 15.3 µg/mL). CONCLUSION: The results suggest the potential for HDI between the herbs and the substrates of the affected enzymes, if sufficient in vivo concentration is attained.


Asunto(s)
Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2C9/metabolismo , Citocromo P-450 CYP3A/metabolismo , Interacciones de Hierba-Droga , Preparaciones Farmacéuticas/metabolismo , Extractos Vegetales/farmacología , Plantas Medicinales , Citocromo P-450 CYP2C19/metabolismo , Diclofenaco/metabolismo , Euphorbiaceae , Humanos , Hidroxilación , Liliaceae , Magnoliopsida , Mefenitoína/metabolismo , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Fenacetina/metabolismo , Sudáfrica , Testosterona/metabolismo
17.
Drug Metab Lett ; 7(2): 83-95, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24475926

RESUMEN

The purpose of this study was to evaluate the potential risk of common herbal medicines used by HIV-infected patients in Africa for herb-drug interactions (HDI). High throughput screening assays consisting of recombinant Cytochrome P450 enzymes (CYPs) and fluorescent probes, and parallel artificial membrane permeability assays (PAMPA) were used. The potential of herbal medicines to cause HDI was ranked according to FDA guidelines for reversible inhibition and categorization of time dependent inhibition was based on the normalized ratio. CYPs 1A2 and 3A4 were most inhibited by the herbal extracts. H. hemerocallidea (IC50 = 0.63 µg/mL and 58 µg/mL) and E. purpurea (IC50 = 20 µg/mL and 12 µg/mL) were the potent inhibitors of CYPs 1A2 and 3A4 respectively. L. frutescens and H. hemerocallidea showed clear time dependent inhibition on CYP3A4. Furthermore, the inhibitory effect of both H. hemerocallidea and L. frutescens before and after PAMPA were identical. The results indicate potential HDI of H. hemerocallidea, L. frutescens and E. purpurea with substrates of the affected enzymes if maximum in vivo concentration is achieved.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Inhibidores Enzimáticos del Citocromo P-450/efectos adversos , Sistema Enzimático del Citocromo P-450/metabolismo , Infecciones por VIH/tratamiento farmacológico , Interacciones de Hierba-Droga , Preparaciones de Plantas/efectos adversos , África , Relación Dosis-Respuesta a Droga , Infecciones por VIH/diagnóstico , Ensayos Analíticos de Alto Rendimiento , Humanos , Isoenzimas , Fitoterapia , Plantas Medicinales , Proteínas Recombinantes/metabolismo , Medición de Riesgo , Factores de Riesgo , Especificidad por Sustrato
18.
Biomed Pharmacother ; 68(5): 665-77, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24863536

RESUMEN

Clinically relevant drug-drug interactions (DDIs) refer to the pharmacological or clinical response to the administration or co-exposure of a drug with another drug that modifies the patient's response. Treatment regimens, which include agents that are involved in the cytochrome P450 (CYP450) enzyme system and transporter systems, such as P-glycoprotein may be associated with higher risk of clinically significant drug interactions. In addition, potential DDIs increase with the increasing number of concomitant drugs. HIV positive cancer patients who receive concomitant chemotherapy and combination antiretroviral therapy (cART) may achieve better response rates and higher rates of survival than those who receive chemotherapy alone, but they may be at increased risk of drug interactions. DDIs in HIV positive cancer patients receiving concomitant chemotherapy and cART may increase or decrease antineoplastic drug concentrations, potentially resulting in life threatening interactions, increased toxicity or loss of efficacy. Avoiding and managing potential interactions between cART and antineoplastic agents is an increasingly important challenge. Based on the current literature, more safety and pharmacokinetic studies are needed with the aim to document a clear survival benefit for patients undergoing chemotherapy and concomitant or sequential administration of cART.


Asunto(s)
Interacciones Farmacológicas , Seropositividad para VIH/complicaciones , Seropositividad para VIH/tratamiento farmacológico , Neoplasias/complicaciones , Neoplasias/tratamiento farmacológico , Humanos
19.
Biomark Cancer ; 6: 11-20, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25057241

RESUMEN

Cancer biomarkers have provided great opportunities for improving the management of cancer patients by enhancing the efficiency of early detection, diagnosis, and efficacy of treatment. Every cell type has a unique molecular signature, referred to as biomarkers, which are identifiable characteristics such as levels or activities of a myriad of genes, proteins, or other molecular features. Biomarkers can facilitate the molecular definition of cancer, provide information about the course of cancer, and predict response to chemotherapy. They offer the hope of early detection as well as tracking disease progression and recurrence. Current progress in the characterization of molecular genetics of HIV-associated cancers may form the basis for improved patient stratification and future targeted or individualized therapies. Biomarker use for cancer staging and personalization of therapy at the time of diagnosis could improve patient care. This review focuses on the relevance of biomarkers in the most common HIV-associated malignancies, namely, Kaposi sarcoma, non-Hodgkin's lymphoma, and invasive cervical cancer.

20.
PLoS One ; 9(2): e89612, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24586912

RESUMEN

OBJECTIVES: To evaluate the safety, tolerability and immunogenicity of three different doses (5, 25 and 50 µg) of the novel antituberculous vaccine RUTI compared to placebo in subjects with latent tuberculosis infection. METHODS AND FINDINGS: Double-blind, randomized, placebo-controlled Phase II Clinical Trial (95 patients randomized). Three different RUTI doses and placebo were tested, randomized both in HIV-positive (n = 47) and HIV-negative subjects (n = 48), after completion of one month isoniazid (INH) pre-vaccination. Each subject received two vaccine administrations, 28 Days apart. Five patients withdrew and 90 patients completed the study. Assessment of safety showed no deaths during study. Two subjects had serious adverse events one had a retinal detachment while taking INH and was not randomized and the other had a severe local injection site abscess on each arm and was hospitalized; causality was assessed as very likely and by the end of the study the outcome had resolved. All the patients except 5 (21%) patients of the placebo group (3 HIV+ and 2 HIV-) reported at least one adverse event (AE) during the study. The most frequently occurring AEs among RUTI recipients were (% in HIV+/-): injection site reactions [erythema (91/92), induration (94/92), local nodules (46/25), local pain (66/75), sterile abscess (6/6), swelling (74/83), ulcer (20/11), headache (17/22) and nasopharyngitis (20/5)]. These events were mostly mild and well tolerated. Overall, a polyantigenic response was observed, which differed by HIV- status. The best polyantigenic response was obtained when administrating 25 µg RUTI, especially in HIV-positive subjects which was not increased after the second inoculation. CONCLUSION: This Phase II clinical trial demonstrates reasonable tolerability of RUTI. The immunogenicity profile of RUTI vaccine in LTBI subjects, even being variable among groups, allows us considering one single injection of one of the highest doses in future trials, preceded by an extended safety clinical phase. TRIAL REGISTRATION: ClinicalTrials.gov NCT01136161.


Asunto(s)
Tuberculosis Latente/etiología , Tuberculosis Latente/terapia , Vacunas contra la Tuberculosis/inmunología , Vacunas contra la Tuberculosis/uso terapéutico , Adulto , Método Doble Ciego , Femenino , Estudios de Seguimiento , VIH/aislamiento & purificación , Infecciones por VIH/complicaciones , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Pronóstico , Seguridad , Vacunación
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