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1.
Clin Case Rep ; 9(10): e04903, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34631086

RESUMO

Low-dose interferon-α 2a treatment may be considered as an alternative to cytoreductive therapy with hydroxyurea or regularly dosed interferon in high-risk polycythemia vera patients.

2.
Obes Facts ; 13(6): 584-595, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33202416

RESUMO

BACKGROUND: Most patients with severe obesity show glucose intolerance. Early after sleeve gastrectomy (LSG) or gastric bypass (LRYGB), a marked amelioration in glycemic control occurs. The underlying mechanism is not yet clear. OBJECTIVE: To determine whether the improvement in glycemic control on the level of endocrine pancreatic function is due to an increased first-phase insulin secretion comparing LRYGB to LSG. SETTING: University of Basel Hospital and St. Clara Research Ltd., Basel, Switzerland. METHODS: Sixteen morbidly obese patients with severe obesity and different degrees of insulin resistance were randomized to LSG or LRYGB, and islet cell functions were tested by intravenous glucose and intravenous arginine administration before and 4 weeks after surgery. RESULTS: Fasting insulin and glucose levels and homeostasis model assessment insulin resistance were significantly lower in both groups after surgery compared to baseline, while no change was seen in fasting C-peptide, amylin, and glucagon. After intravenous glucose stimulation, no statistically significant pre- to postoperative change in area under the curve (AUC 0-60 min) was seen for insulin, glucagon, amylin, and C-peptide. No statistically significant pre- to postoperative change in incremental AUC for first-phase insulin release (AUC 0-10 min), second-phase insulin secretion (AUC 10-60 min), and insulin/glucose ratio could be shown in either group. Arginine-stimulated insulin and glucagon release showed no pre- to postoperative change. CONCLUSION: Intravenous glucose and arginine administrations show no pre- to postoperative changes of insulin release, amylin, glucagon, or C-peptide concentrations, and no differences between LRYGB and LSG were found. The postoperative improvement in glycemic control is not caused by changes in endocrine pancreatic hormone secretion.


Assuntos
Diabetes Mellitus/etiologia , Resistência à Insulina , Insulina/sangue , Polipeptídeo Amiloide das Ilhotas Pancreáticas/sangue , Obesidade Mórbida/cirurgia , Adulto , Cirurgia Bariátrica , Jejum , Feminino , Gastrectomia , Derivação Gástrica , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/complicações , Período Pós-Operatório , Estudos Prospectivos
3.
Basic Clin Pharmacol Toxicol ; 121(5): 423-429, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28561421

RESUMO

Little is known about the course of the plasma concentration and the bioavailability of non-steroidal anti-inflammatory drugs (NSAIDs) contained in dermal patches. We compared an etofenamate prototype patch (patent EP 1833471) and a commercially available diclofenac epolamine patch regarding the bioavailability of the active ingredients relative to respective i.m. applications and regarding their plasma concentration-time course. Twenty-four healthy human volunteers were treated using a parallel group design (n = 12 per group) with a single dermal patch (removed after 12 hr) followed (after a latency of 48 hr) by eight consecutive dermal patches every 12 hr to reach steady-state conditions. The patches were generally well tolerated, but one volunteer treated with etofenamate developed an allergic contact dermatitis. After the first patch, Cmax was 0.81 ± 0.11 (mean ± S.E.M.) ng/mL (reached 12 hr after patch removal) for diclofenac and 31.3 ± 3.8 ng/mL for flufenamic acid (reached at patch removal), the main metabolite of etofenamate. Etofenamate was not detectable. After repetitive dosing, trough plasma concentrations after the eighth dose were 1.72 ± 0.32 ng/mL for diclofenac and 48.7 ± 6.6 ng/mL for flufenamic acid. Bioavailabilities (single dose) relative to i.m. applications were 0.22 ± 0.04% for diclofenac and 1.15 ± 0.06% for flufenamic acid. In conclusion, the relative bioavailability (compared to the respective i.m. application) of both drugs is low. The maximal plasma concentrations after topical administration of these drugs are well below the IC50 values for COX-1 and COX-2, explaining the absence of dose-dependent toxicities.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Diclofenaco/administração & dosagem , Ácido Flufenâmico/análogos & derivados , Administração Cutânea , Adolescente , Adulto , Anti-Inflamatórios não Esteroides/farmacocinética , Disponibilidade Biológica , Estudos Cross-Over , Diclofenaco/farmacocinética , Esquema de Medicação , Feminino , Ácido Flufenâmico/administração & dosagem , Ácido Flufenâmico/metabolismo , Ácido Flufenâmico/farmacocinética , Humanos , Concentração Inibidora 50 , Injeções Intramusculares , Masculino , Adesivo Transdérmico , Adulto Jovem
4.
Biofactors ; 43(3): 388-399, 2017 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-28139053

RESUMO

Ze339, an herbal extract from Petasites hybridus leaves is effective in treatment of allergic rhinitis by inhibition of a local production of IL-8 and eicosanoid LTB4 in allergen-challenged patients. However, the mechanism of action and anti-inflammatory potential in virally induced exacerbation of the upper airways is unknown. This study investigates the anti-inflammatory mechanisms of Ze339 on primary human nasal epithelial cells (HNECs) upon viral, bacterial and pro-inflammatory triggers. To investigate the influence of viral and bacterial infections on the airways, HNECs were stimulated with viral mimics, bacterial toll-like-receptor (TLR)-ligands or cytokines, in presence or absence of Ze339. The study uncovers Ze339 modulated changes in pro-inflammatory mediators and decreased neutrophil chemotaxis as well as a reduction of the nuclear translocation and phosphorylation of STAT molecules. Taken together, this study suggests that phyto drug Ze339 specifically targets STAT-signalling pathways in HNECs and has high potential as a broad anti-inflammatory drug that exceeds current indication. © 2016 BioFactors, 43(3):388-399, 2017.


Assuntos
Células Epiteliais/efeitos dos fármacos , Petasites/química , Extratos Vegetais/farmacologia , Fatores de Transcrição STAT/antagonistas & inibidores , Sesquiterpenos/farmacologia , Movimento Celular/efeitos dos fármacos , Quimiocinas/antagonistas & inibidores , Quimiocinas/biossíntese , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Flagelina/antagonistas & inibidores , Flagelina/farmacologia , Regulação da Expressão Gênica , Humanos , Interferon gama/antagonistas & inibidores , Interferon gama/farmacologia , Interleucina-4/antagonistas & inibidores , Interleucina-4/farmacologia , Lipopeptídeos/antagonistas & inibidores , Lipopeptídeos/farmacologia , Cavidade Nasal/citologia , Cavidade Nasal/efeitos dos fármacos , Cavidade Nasal/metabolismo , Neutrófilos/efeitos dos fármacos , Folhas de Planta/química , Poli I-C/antagonistas & inibidores , Poli I-C/farmacologia , Cultura Primária de Células , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais
5.
Ann Surg ; 265(3): 466-473, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28170356

RESUMO

OBJECTIVE: Laparoscopic sleeve gastrectomy (LSG) is performed almost as often in Europe as laparoscopic Roux-Y-Gastric Bypass (LRYGB). We present the 3-year interim results of the 5-year prospective, randomized trial comparing the 2 procedures (Swiss Multicentre Bypass Or Sleeve Study; SM-BOSS). METHODS: Initially, 217 patients (LSG, n = 107; LRYGB, n = 110) were randomized to receive either LSG or LRYGB at 4 bariatric centers in Switzerland. Mean body mass index of all patients was 44 ±â€Š11 kg/m, mean age was 43 ±â€Š5.3 years, and 72% of patients were female. Minimal follow-up was 3 years with a rate of 97%. Both groups were compared for weight loss, comorbidities, quality of life, and complications. RESULTS: Excessive body mass index loss was similar between LSG and LRYGB at each time point (1 year: 72.3 ±â€Š21.9% vs. 76.6 ±â€Š20.9%, P = 0.139; 2 years: 74.7 ±â€Š29.8% vs. 77.7 ±â€Š30%, P = 0.513; 3 years: 70.9 ±â€Š23.8% vs. 73.8 ±â€Š23.3%, P = 0.316). At this interim 3-year time point, comorbidities were significantly reduced and comparable after both procedures except for gastro-esophageal reflux disease and dyslipidemia, which were more successfully treated by LRYGB. Quality of life increased significantly in both groups after 1, 2, and 3 years postsurgery. There was no statistically significant difference in number of complications treated by reoperation (LSG, n = 9; LRYGB, n = 16, P = 0.15) or number of complications treated conservatively. CONCLUSIONS: In this trial, LSG and LRYGB are equally efficient regarding weight loss, quality of life, and complications up to 3 years postsurgery. Improvement of comorbidities is similar except for gastro-esophageal reflux disease and dyslipidemia that appear to be more successfully treated by LRYGB.


Assuntos
Gastrectomia/métodos , Derivação Gástrica/métodos , Obesidade Mórbida/cirurgia , Qualidade de Vida , Adulto , Análise de Variância , Anastomose em-Y de Roux/efeitos adversos , Anastomose em-Y de Roux/métodos , Índice de Massa Corporal , Feminino , Seguimentos , Gastrectomia/efeitos adversos , Derivação Gástrica/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Prospectivos , Reoperação/estatística & dados numéricos , Medição de Risco , Suíça , Fatores de Tempo , Resultado do Tratamento , Redução de Peso
6.
Am J Physiol Endocrinol Metab ; 310(11): E1053-61, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27117004

RESUMO

With the increasing prevalence of obesity and a possible association with increasing sucrose consumption, nonnutritive sweeteners are gaining popularity. Given that some studies indicate that artificial sweeteners might have adverse effects, alternative solutions are sought. Xylitol and erythritol have been known for a long time and their beneficial effects on caries prevention and potential health benefits in diabetic patients have been demonstrated in several studies. Glucagon-like peptide-1 (GLP-1) and cholecystokinin (CCK) are released from the gut in response to food intake, promote satiation, reduce gastric emptying (GE), and modulate glucose homeostasis. Although glucose ingestion stimulates sweet taste receptors in the gut and leads to incretin and gastrointestinal hormone release, the effects of xylitol and erythritol have not been well studied. Ten lean and 10 obese volunteers were given 75 g of glucose, 50 g of xylitol, or 75 g of erythritol in 300 ml of water or placebo (water) by a nasogastric tube. We examined plasma glucose, insulin, active GLP-1, CCK, and GE with a [(13)C]sodium acetate breath test and assessed subjective feelings of satiation. Xylitol and erythritol led to a marked increase in CCK and GLP-1, whereas insulin and plasma glucose were not (erythritol) or only slightly (xylitol) affected. Both xylitol and erythritol induced a significant retardation in GE. Subjective feelings of appetite were not significantly different after carbohydrate intake compared with placebo. In conclusion, acute ingestion of erythritol and xylitol stimulates gut hormone release and slows down gastric emptying, whereas there is no or only little effect on insulin release.


Assuntos
Esvaziamento Gástrico/efeitos dos fármacos , Hormônios/metabolismo , Resistência à Insulina , Mucosa Intestinal/metabolismo , Obesidade/fisiopatologia , Edulcorantes/administração & dosagem , Magreza/fisiopatologia , Administração Oral , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eritritol/administração & dosagem , Feminino , Glucose/administração & dosagem , Humanos , Intestinos/efeitos dos fármacos , Masculino , Efeito Placebo , Xilitol/administração & dosagem
7.
J Control Release ; 232: 248-54, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27090163

RESUMO

Nicotine substitution is a mainstay component in smoking cessation schemes. Current products including patches are poorly effective mainly because they do not give smokers the same pharmacokinetic profile of nicotine as cigarette consumption. This work evaluates a new computer operated delivery system for time controlled pulsatile transdermal administration of nicotine in a phase I clinical trial with twelve heavy smoking male volunteers. The device was affixed to the ventral side of the leading lower arm of the subjects and was programmed to deliver two pulses of drug within 16h with three delivery rates in a consecutive dose escalation study. Tolerability of the three increasing doses of nicotine was established. Plasma concentration of nicotine exhibited two peaks and one trough and reached therapeutically effective levels that behaved linearly with the drug load concentration of the device. In vivo input rate, delivered amount and elimination kinetics were deduced by pharmacokinetic modeling to analyze device performance. Timing, dose and duration of delivery were controlled by system operation parameters. Hence, feasibility of controlled pulsatile delivery of nicotine at predetermined intervals was demonstrated. After additional optimization, preprogrammed or on demand administration to meet individualized and circadian replacement needs should improve smoking cessation efficacy.


Assuntos
Nicotina/administração & dosagem , Administração Cutânea , Adulto , Estudos de Viabilidade , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/sangue , Nicotina/farmacocinética , Fumantes , Adulto Jovem
8.
PLoS One ; 11(3): e0150803, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26942445

RESUMO

BACKGROUND/OBJECTIVES: The changes in blood glucose concentrations that result from an oral glucose challenge are dependent on the rate of gastric emptying, the rate of glucose absorption and the rate of insulin-driven metabolism that include the incretins, glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide-1 (GLP-1). The rate of insulin-driven metabolism is clearly altered in obese subjects, but it is controversial which of these factors is predominant. We aimed to quantify gastric emptying, plasma insulin, C-peptide, glucagon and glucose responses, as well as incretin hormone secretions in obese subjects and healthy controls during increasing glucose loads. SUBJECTS/METHODS: The study was conducted as a randomized, double-blind, parallel-group trial in a hospital research unit. A total of 12 normal weight (6 men and 6 women) and 12 non-diabetic obese (BMI > 30, 6 men and 6 women) participants took part in the study. Subjects received intragastric loads of 10 g, 25 g and 75 g glucose dissolved in 300 ml tap water. RESULTS: Main outcome measures were plasma GLP-1 and GIP, plasma glucagon, glucose, insulin, C-peptide and gastric emptying. The primary findings are: i) insulin resistance (P < 0.001) and hyperinsulinemia (P < 0.001); ii) decreased insulin disposal (P < 0.001); iii) trend for reduced GLP-1 responses at 75 g glucose; and iv) increased fasting glucagon levels (P < 0.001) in obese subjects. CONCLUSIONS: It seems that, rather than changes in incretin secretion, fasting hyperglucagonemia and consequent hyperglycemia play a role in reduced disposal of insulin, contributing to hyperinsulinemia and insulin resistance. TRIAL REGISTRATION: ClinicalTrials.gov NCT01875575.


Assuntos
Glucose/metabolismo , Insulina/metabolismo , Obesidade/metabolismo , Adulto , Glicemia/análise , Índice de Massa Corporal , Peso Corporal , Peptídeo C/sangue , Estudos de Casos e Controles , Diabetes Mellitus , Método Duplo-Cego , Feminino , Esvaziamento Gástrico , Polipeptídeo Inibidor Gástrico/sangue , Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Glucose/administração & dosagem , Humanos , Incretinas/metabolismo , Insulina/sangue , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Adulto Jovem
9.
Springerplus ; 4: 65, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25713759

RESUMO

The cardinal climacteric symptoms of hot flushes and night sweats affect 24-93% of all women during the physiological transition from reproductive to post-reproductive life. Though efficacious, hormonal therapy and partial oestrogenic compounds are linked to a significant increase in breast cancer. Non-hormonal treatments are thus greatly appreciated. This systematic review of published hormonal and non-hormonal treatments for climacteric, and breast and prostate cancer-associated hot flushes, examines clinical efficacy and therapy-related cancer risk modulation. A PubMed search included literature up to June 19, 2014 without limits for initial dates or language, with the search terms, (hot flush* OR hot flash*) AND (clinical trial* OR clinical stud*) AND (randomi* OR observational) NOT review). Retrieved references identified further papers. The focus was on hot flushes; other symptoms (night sweats, irritability, etc.) were not specifically screened. Included were some 610 clinical studies where a measured effect of the intervention, intensity and severity were documented, and where patients received treatment of pharmaceutical quality. Only 147 of these references described studies with alternative non-hormonal treatments in post-menopausal women and in breast and prostate cancer survivors; these results are presented in Additional file 1. The most effective hot flush treatment is oestrogenic hormones, or a combination of oestrogen and progestins, though benefits are partially outweighed by a significantly increased risk for breast cancer development. This review illustrates that certain non-hormonal treatments, including selective serotonin reuptake inhibitors, gabapentin/pregabalin, and Cimicifuga racemosa extracts, show a positive risk-benefit ratio. Key pointsSeveral non-hormonal alternatives to hormonal therapy have been established and registered for the treatment of vasomotor climacteric symptoms in peri- and post-menopausal women.There are indications that non-hormonal treatments are useful alternatives in patients with a history of breast and prostate cancer. However, confirmation by larger clinical trials is required.

10.
Expert Opin Drug Metab Toxicol ; 10(5): 665-71, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24588496

RESUMO

INTRODUCTION: Patients, in particular elderly ones, frequently receive more than one drug at a time. With each drug added to a regime, the number of potential drug-drug interactions (DDIs) increases by a power law. Early prediction of relevant interactions by computerized tools greatly aids clinicians and can guide their prescribing choices. AREAS COVERED: In this article, we discuss different types of DDIs, on which levels they can arise and what efforts have been made in the past to detect and predict them. The emphasis is on data mining technology and network analysis, but overlaps with traditional pharmacovigilance are also discussed. Finally, we discuss strategies to focus and simplify mining efforts to get meaningful results with less effort. EXPERT OPINION: The necessary technology for detecting adverse DDIs exists and is quite refined, although it is more often implied in lower risk scenarios (such as syntactic analysis in web searches and online libraries). Data mining for DDIs, on the other hand, still requires a great deal of human intervention, not only to validate the results but also, more importantly, to separate the relevant from the spurious. The fields of network analysis and graph theory show great promise but have not yet shown much beyond descriptive analyses.


Assuntos
Mineração de Dados , Interações Medicamentosas , Modelos Biológicos , Farmacovigilância , Geriatria/métodos , Geriatria/tendências , Humanos , Farmacologia Clínica/métodos , Farmacologia Clínica/tendências
11.
Phytomedicine ; 20(8-9): 659-66, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23537746

RESUMO

BACKGROUND: Root extracts of Cimicifuga racemosa (L.) Nutt. have been successfully used in the treatment of climacteric complaints. METHOD: In this observational study, Cimicifuga racemosa (CR) extract Ze 450 was studied in 442 unselected ambulatory female outpatients with menopausal complaints under daily practice conditions. Physicians were suggested to treat patients for the first 3 months with 13 mg/d CR (high dose, HD) and to continue over additional 6 months either with this treatment or to switch to 6.5mg/d CR (low dose, LD). The choice of treatment and its dose, however, was fully at the discretion of the physician. RESULTS: After 3-months treatment with HD, symptom severity (Kupperman Menopause Index, KMI) decreased significantly (p<0.001) from baseline values. Continuation of treatment with HD or LD decreased total KMI and its sub-item scores further (HD, LD: p<0.001). However, more patients (84.9%) responded to HD than to LD (78.4%) and showed an improvement of symptoms (p=0.011). CONCLUSION: This observational study demonstrated that treatment with CR in unselected patients with climacteric complaints under the conditions of daily practice resulted in a significant improvement of menopausal symptoms assessed by the total KMI score and its sub-item scores with an effect size similar to that in a previous randomized, controlled clinical trial.


Assuntos
Cimicifuga/química , Menopausa/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/uso terapêutico , Raízes de Plantas/química , Adulto , Idoso , Assistência Ambulatorial , Demografia , Feminino , Fogachos/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Estudos Prospectivos , Suíça , Resultado do Tratamento
12.
Expert Opin Drug Discov ; 7(4): 341-52, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22458505

RESUMO

INTRODUCTION: Decision tree induction (DTI) is a powerful means of modeling data without much prior preparation. Models are readable by humans, robust and easily applied in real-world applications, features that are mutually exclusive in other commonly used machine learning paradigms. While DTI is widely used in disciplines ranging from economics to medicine, they are an intriguing option in pharmaceutical research, especially when dealing with large data stores. AREAS COVERED: This review covers the automated technologies available for creating decision trees and other rules efficiently, even from large datasets such as chemical libraries. The authors discuss the need for properly documented and validated models. Lastly, the authors cover several case studies in hit discovery, drug metabolism and toxicology, and drug surveillance, and compare them with other established techniques. EXPERT OPINION: DTI is a competitive and easy-to-use tool in basic research as well as in hit and drug discovery. Its strengths lie in its ability to handle all sorts of different data formats, the visual nature of the models, and the small computational effort needed for implementation in real-world systems. Limitations include lack of robustness and over-fitted models for certain types of data. As with any modeling technique, proper validation and quality measures are of utmost importance.


Assuntos
Mineração de Dados , Árvores de Decisões , Descoberta de Drogas , Modelos Teóricos , Algoritmos , Inteligência Artificial , Ensaios de Triagem em Larga Escala , Humanos , Armazenamento e Recuperação da Informação , Farmacocinética , Bibliotecas de Moléculas Pequenas , Software
13.
Planta Med ; 78(7): 686-91, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22411724

RESUMO

The most important psychoactive constituent of CANNABIS SATIVA L. is Δ (9)-tetrahydrocannabinol (THC). Cannabidiol (CBD), another important constituent, is able to modulate the distinct unwanted psychotropic effect of THC. In natural plant extracts of C. SATIVA, large amounts of THC and CBD appear in the form of THCA-A (THC-acid-A) and CBDA (cannabidiolic acid), which can be transformed to THC and CBD by heating. Previous reports of medicinal use of cannabis or cannabis preparations with higher CBD/THC ratios and use in its natural, unheated form have demonstrated that pharmacological effects were often accompanied with a lower rate of adverse effects. Therefore, in the present study, the pharmacokinetics and metabolic profiles of two different C. SATIVA extracts (heated and unheated) with a CBD/THC ratio > 1 were compared to synthetic THC (dronabinol) in a double-blind, randomized, single center, three-period cross-over study involving 9 healthy male volunteers. The pharmacokinetics of the cannabinoids was highly variable. The metabolic pattern was significantly different after administration of the different forms: the heated extract showed a lower median THC plasma AUC (24 h) than the unheated extract of 2.84 vs. 6.59 pmol h/mL, respectively. The later was slightly higher than that of dronabinol (4.58 pmol h/mL). On the other hand, the median sum of the metabolites (THC, 11-OH-THC, THC-COOH, CBN) plasma AUC (24 h) was higher for the heated than for the unheated extract. The median CBD plasma AUC (24 h) was almost 2-fold higher for the unheated than for the heated extract. These results indicate that use of unheated extracts may lead to a beneficial change in metabolic pattern and possibly better tolerability.


Assuntos
Canabidiol/farmacocinética , Cannabis/química , Dronabinol/farmacocinética , Fitoterapia , Extratos Vegetais/farmacocinética , Adulto , Área Sob a Curva , Canabidiol/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Dronabinol/sangue , Temperatura Alta , Humanos , Masculino , Metaboloma/efeitos dos fármacos , Extratos Vegetais/sangue , Psicotrópicos/sangue , Valores de Referência , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-23346194

RESUMO

Extracts from Cimicifuga racemosa (CR, synonym Actaea racemosa) have shown efficacy in trials in women with menopausal symptoms. Yet, dose dependency remains unclear. Therefore, 180 female outpatients with climacteric complaints were treated for 12 weeks in a randomized, double-blind, placebo-controlled, 3-armed trial (CR extract Ze 450 in 6.5 mg or 13.0 mg, or placebo). Primary outcome was the difference in menopausal symptoms (vasomotor, psychological, and somatic), assessed by the Kupperman Menopausal Index between baseline and week 12. Secondary efficacy variables were patients' self-assessments of general quality of life (QoL), responder rates, and safety. Compared to placebo, patients receiving Ze 450 showed a significant reduction in the severity of menopausal symptoms in a dose-dependent manner from baseline to endpoint (mean absolute differences 17.0 (95% CI 14.65-19.35) score points, P < 0.0001 for 13.0 mg; mean absolute differences 8.47 (95% CI 5.55-11.39) score points, P = 0.0003 for 6.5 mg). QoL and responder rates corresponded with the main endpoint. Changes in menopausal symptoms and QoL were inversely correlated. Reported adverse events and clinical laboratory testing did not raise safety concerns. The CR extract Ze 450 is an effective and well-tolerated nonhormonal alternative to hormone treatment for symptom relief in menopausal women.

15.
Expert Opin Drug Metab Toxicol ; 6(11): 1437-44, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20955109

RESUMO

IMPORTANCE OF THE FIELD: Idebenone is a synthetic short chain benzoquinone that acts as an electron carrier in the mitochondrial electron transport chain, thereby, facilitating the production of ATP. In addition, idebenone is an antioxidant and can inhibit lipid peroxidation and may protect cell membranes and mitochondria from oxidative damage. High dose idebenone (Catena(®)) is approved in Canada for the symptomatic treatment of Friedreich's ataxia and is currently under clinical investigation for use in a number of mitochondrial and neuromuscular diseases. AREAS COVERED IN THIS REVIEW: This review summarizes the pharmacology, pharmacokinetic and clinical efficacy/safety data of idebenone and its metabolites and provides an update of the clinical trials completed and in progress. WHAT THE READER WILL GAIN: Following oral administration, idebenone is rapidly metabolized via oxidative shortening by a number CYP isoenzymes (CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4) to yield QS10, QS8, QS6 and QS4. Idebenone and these metabolites concomitantly undergo conjugation via glucuronidation and sulfatation to yield conjugated moieties represented as idebenone-C, QS10-C, QS8-C, QS6-C and QS4-C. Previous reports in the literature were only able to quantify plasma concentrations of idebenone measured together with its conjugates. More recently, highly sensitive and specific liquid chromatography method with tandem mass spectrometric methods have been developed, allowing the quantification of the parent molecule idebenone and its main metabolite QS10, separately. TAKE HOME MESSAGE: After absorption, idebenone is rapidly metabolized by first pass metabolism and shows dose-proportional pharmacokinetics in healthy subjects in daily doses up to 2250 mg. The recent development of advanced analytical techniques allows the detection of idebenone and unconjugated metabolites in plasma and consequently opens the possibility for evaluation of pharmacokinetic/pharmacodynamic relationships which will be helpful to further understand the metabolism and therapeutic potential of idebenone. In clinical studies, idebenone was safe and well tolerated at doses up to 2250 mg/day.


Assuntos
Antioxidantes/farmacocinética , Ataxia de Friedreich/tratamento farmacológico , Ubiquinona/análogos & derivados , Administração Oral , Animais , Antioxidantes/efeitos adversos , Antioxidantes/uso terapêutico , Cromatografia Líquida/métodos , Sistema Enzimático do Citocromo P-450/metabolismo , Relação Dose-Resposta a Droga , Humanos , Espectrometria de Massas em Tandem/métodos , Ubiquinona/efeitos adversos , Ubiquinona/farmacocinética , Ubiquinona/uso terapêutico
16.
J Chromatogr B Analyt Technol Biomed Life Sci ; 878(28): 2726-32, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20846915

RESUMO

A fully automated screening using liquid chromatography-mass spectrometric method applying data-dependent acquisition was developed to identify toxicologically relevant substances in serum and urine. A library including more than 405 spectra of about 365 compounds (main drugs and important metabolites) was established. An easy to use program was created to automate and accelerate library search. Drugs were identified based on their relative retention times, molecular ions and fragment ions. Limits of detection were tested with 100 of the 365 compounds the majority of these were lower than 100µg/l (67%). The developed LC-MS-MS system seems to be a valuable alternative to other general unknown screening methods allowing fast and specific identification of drugs in serum and urine samples.


Assuntos
Automação Laboratorial , Cromatografia Líquida de Alta Pressão/métodos , Preparações Farmacêuticas/análise , Espectrometria de Massas em Tandem/métodos , Bases de Dados Factuais , Humanos , Preparações Farmacêuticas/sangue , Preparações Farmacêuticas/urina , Extração em Fase Sólida/métodos
17.
Mol Pharm ; 7(5): 1618-28, 2010 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-20701289

RESUMO

P-glycoprotein (P-gp/MDR1/ABCB1) and breast cancer resistance protein (BCRP/ABCG2) play an important role in transport of a wide variety of endogenous compounds, drugs and toxins. Transport of some drugs, for example the tyrosine kinase inhibitor imatinib, is influenced by both P-gp and BCRP. Establishing an intestinal Caco-2 cell culture model with specific knock-downs of P-gp and BCRP and double knock-down of both proteins, we aimed to elucidate the impact of each transporter on transport of imatinib. Stable single and double knock-downs of P-gp and BCRP were obtained by RNA interference (RNAi). Transporter expression was measured on RNA and protein level using real-time RT-PCR and Western blot, respectively. Functional activity was quantified by transport of specific substrates across Caco-2 cells. MDR1 and BCRP mRNA expression was reduced to 75% and 90% compared to wild-type control in single MDR1- and BCRP-knock-down clones, respectively. In double knock-down clones, MDR1 expression decreased to 95% and BCRP expression to 80%. Functional activity of P-gp and BCRP was diminished as transport of the P-gp-specific substrate (3)H-digoxin and the BCRP-specific substrate (14)C-PhIP was augmented in the opposite direction, when the respective transporter was knocked down. Similar effects were observed by chemical inhibition of the respective transporter. Bidirectional transport studies with (14)C-imatinib revealed an abrogation of asymmetric transport when P-gp was knocked down, either in single or double knock-down clones compared to wild-type cells. This was not observed in single BCRP-knock-down clones. In conclusion, this newly established cell system with single and concomitant knock-down of P-gp and BCRP can be used to quantify the specific partial impact of the transporters on transport of substrates that are transported by both proteins. For imatinib transport, the contribution of P-gp seems to be more important compared to BCRP in this Caco-2 cell system.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Benzamidas/farmacocinética , Mucosa Intestinal/metabolismo , Modelos Biológicos , Proteínas de Neoplasias/metabolismo , Piperazinas/farmacocinética , Pirimidinas/farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Sequência de Bases , Transporte Biológico Ativo , Células CACO-2 , Técnicas de Silenciamento de Genes , Humanos , Mesilato de Imatinib , Absorção Intestinal , Cinética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Inibidores de Proteínas Quinases/farmacocinética , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Especificidade por Substrato
18.
Am J Clin Nutr ; 92(4): 810-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20720259

RESUMO

BACKGROUND: Peripheral infusion of glucagon-like peptide 1 (GLP-1) or peptide YY 3-36 (PYY3-36) reduces food intake in healthy, obese, and diabetic subjects. In vivo, both peptides are cosecreted from intestinal L cells; GLP-1 is subject to rapid breakdown by dipeptidyl peptidase IV, and together with PYY3-36 it is likely to be degraded in the liver before entering the systemic circulation. The largest concentrations are observed in the splanchnic blood rather than in the systemic circulation. OBJECTIVE: In contrast with peripheral infusion, oral delivery of sodium N-[8-(2-hydroxybenzoyl) amino] caprylate (SNAC) mimics endogenous secretion. We aimed to investigate how this affects food intake. DESIGN: Twelve healthy male subjects were studied in a randomized, double-blind, placebo-controlled, 4-way crossover trial. Each subject received in random order 2.0 mg GLP-1, 1.0 mg PYY3-36, or 2.0 mg GLP-1 plus 1.0 mg PYY3-36; the peptides were mixed with SNAC. The placebo treatment was the delivery agent alone. Food intake during an ad libitum test meal was measured. RESULTS: Both peptides were rapidly absorbed from the gut, leading to plasma concentrations several times higher than those in response to a normal meal. GLP-1 alone, but not PYY3-36, reduced total energy intake significantly, with marked effects on glucose homeostasis. Coadministration of both peptides reduced total energy intake by 21.5% and fullness at meal onset (P < 0.05) but not total 24-h energy intake. CONCLUSION: The results show a marked effect of orally administered GLP-1 and PYY3-36 on appetite by showing enhanced fullness at meal onset and reduced energy intake. This trial was registered at clinicaltrials.gov as NCT00822705.


Assuntos
Ingestão de Alimentos/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Peptídeo YY/farmacologia , Administração Oral , Adulto , Método Duplo-Cego , Metabolismo Energético , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/farmacocinética , Humanos , Fome , Masculino , Fragmentos de Peptídeos , Peptídeo YY/administração & dosagem , Peptídeo YY/farmacocinética , Placebos , Valores de Referência , Saciação , Adulto Jovem
19.
Planta Med ; 76(16): 1866-70, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20509107

RESUMO

Curcuma longa L. is a widely used spice. Its main ingredients, the curcuminoids, are used in the treatment of inflammatory diseases and cancer. Bioavailability of curcuminoids is low, and huge amounts remain in the intestine. We therefore aimed to investigate their interaction potential with the ABC-transporter P-glycoprotein (P-gp, product of the MDR1/ABCB1 gene) and cytochrome P450 3A4 (CYP3A4) in an intestinal cell line (LS180). Intestinal P-gp and CYP3A4 play a major role in drug absorption, and consequently changes in their expression level could lead to interactions. The intestinal LS180 cell line was incubated with different Curcuma extracts, the single curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin), as well as a curcuminoid mixture. Changes in mRNA expression of MDR1 and the cytochrome CYP3A4 were measured by real-time RT-PCR. MDR1 mRNA expression was significantly but not relevantly downregulated by the curcuminoids, whereas the extracts had no significant effect on it. CYP3A4 mRNA expression did not alter significantly after treatment. Curcuma extracts, the single curcuminoids, and a curcuminoid mixture had no relevant effect on MDR1 and CYP3A4 mRNA expression in our intestinal cell system. Further studies are required to evaluate their effects in vivo.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Curcuma/química , Curcumina/farmacologia , Interações Ervas-Drogas , Intestinos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Linhagem Celular , Curcumina/análogos & derivados , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Intestinos/citologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
J Clin Endocrinol Metab ; 95(2): 879-86, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19837920

RESUMO

CONTEXT: Glucagon-like peptide-1 (GLP-1) is produced by specialized cells in the gut and secreted in response to carbohydrates and lipids. The mechanisms regulating fat-stimulated GLP-1 release have, however, not been clarified in detail. AIM: We aimed to investigate the effect of intraduodenal (ID) fat hydrolysis on GLP-1 release and test whether the signal is mediated through cholecystokinin (CCK)-1 receptors. DESIGN AND SETTING: Thirty-four healthy, male ambulatory volunteers were studied in three consecutive, randomized, double blind, crossover studies. INTERVENTION: There were three interventions: 1) 12 subjects received an ID fat infusion with or without orlistat, an irreversible inhibitor of gastrointestinal lipases, in comparison with vehicle; 2) 12 subjects received ID sodium oleate (C18:1), ID sodium caprylate (C8:0), or ID vehicle; and 3) 10 subjects received ID sodium oleate with and without the CCK-1 receptor antagonist dexloxiglumide or ID vehicle plus iv saline (placebo). The effect of these treatments on GLP-1 concentrations and CCK release was quantified. RESULTS: The following results were reached: 1) ID fat induced significant increase in GLP-1 concentrations (P < 0.004), and inhibition of fat hydrolysis by orlistat abolished this effect; 2) sodium oleate significantly stimulated GLP-1 release (P < 0.008), whereas sodium caprylate was ineffective compared with controls; and 3) dexloxiglumide administration abolished the effect of sodium oleate on GLP-1. ID fat or sodium oleate significantly stimulated plasma CCK (P < 0.006 and P < 0.004) compared with saline, whereas sodium caprylate did not. CONCLUSION: Generation of long-chain fatty acids through hydrolysis of fat is a critical step for fat-induced stimulation of GLP-1 in humans; the signal is mediated via CCK release and CCK-1 receptors.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/metabolismo , Lipólise , Adulto , Colecistocinina/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Humanos , Lactonas/farmacologia , Masculino , Ácido Oleico/farmacologia , Orlistate , Ácidos Pentanoicos/farmacologia , Adulto Jovem
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