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1.
Drug Test Anal ; 12(4): 485-495, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31881121

RESUMO

According to WADA guidelines, the presence of Higenamine (HG) in urine should not be ≥10 ng/mL. HG is widely found in materials used in Chinese herbal medicines as well as food and additives. This paper is the first method wherein a rat model has been used to evaluate the pharmacokinetics of orally administered HG by LC-MS/MS and would be helpful in doping control analysis. The method was found to be linear over a concentration range of 0.5(lower limit of quantification, LLOQ)-500 ng/mL for plasma and 0.5(LLOQ)-1000 ng/mL for urine. The values for intra- and inter-day accuracy and precision did not deviate by >12.25% for HG in plasma and 5.87% in urine. Extraction recoveries of HG were 70.30-86.71% from plasma and 74.93%-79.29% from urine. HG was stable in plasma and urine after the extraction process and when exposed to different storage conditions. The findings of this study could provide some reference value for the assessment of HG misuse and for the control of intake and external application of HG-related materials (foods and medicinal herbs). Our key findings are that high levels of external application or oral administration of HG-rich materials may lead to a positive urine test for HG in athletes.


Assuntos
Alcaloides/sangue , Alcaloides/urina , Espectrometria de Massas em Tandem/métodos , Tetra-Hidroisoquinolinas/sangue , Tetra-Hidroisoquinolinas/urina , Administração Oral , Alcaloides/administração & dosagem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo , Feminino , Limite de Detecção , Masculino , Ratos , Ratos Sprague-Dawley , Detecção do Abuso de Substâncias/métodos , Tetra-Hidroisoquinolinas/administração & dosagem
2.
Drug Test Anal ; 11(11-12): 1731-1736, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31680485

RESUMO

Higenamine is a ß2-agonist that has been included in the Prohibited List of the World Anti-Doping Agency (WADA) since 2017. Meanwhile, it exists in plumula nelumbinis, a part of the lotus seed, and is commonly used as an ingredient in cuisines, herbal medicines, and nutritional supplements in China and other countries in East Asia. Therefore, an evaluation of the risk of an adverse analytical finding (AAF) of higenamine caused by plumula nelumbinis products is necessary in doping control. In this study, 14 volunteers took plumula nelumbinis capsules orally (0.34 g/caplet, 6 caplets/day, 7 days), and another 11 volunteers ingested higenamine tablets (three 5 mg tablets/day for 7 days). Urine samples were collected over a period of 14 days. All urine samples were subjected to quantitative dilute-and-shoot analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The analytical results showed that urinary higenamine concentrations exceeded the WADA reporting limit (10 ng/mL) during the drug period in most sample groups. The maximum higenamine concentration observed in the plumula nelumbinis capsule group was 500 ng/mL. Based on confidence interval theory, appropriate data were used to establish mathematical models. The models reflected that the higenamine concentration in urine can exceed the WADA reporting limit with a high probability after taking plumula nelumbinis capsules. In conclusion, oral administration of plumula nelumbinis capsules showed a high risk of an AAF due to higenamine.


Assuntos
Agonistas Adrenérgicos beta/urina , Alcaloides/urina , Espectrometria de Massas em Tandem/métodos , Tetra-Hidroisoquinolinas/urina , Administração Oral , Agonistas Adrenérgicos beta/administração & dosagem , Adulto , Alcaloides/administração & dosagem , Cápsulas , Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Feminino , Humanos , Limite de Detecção , Masculino , Detecção do Abuso de Substâncias/métodos , Tetra-Hidroisoquinolinas/administração & dosagem , Adulto Jovem
3.
Int J Neuropsychopharmacol ; 22(11): 735-745, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31613314

RESUMO

BACKGROUND: New treatments for stress-related disorders including depression, anxiety, and substance use disorder are greatly needed. Kappa opioid receptors are expressed in the central nervous system, including areas implicated in analgesia and affective state. Although kappa opioid receptor agonists share the antinociceptive effects of mu opioid receptor agonists, they also tend to produce negative affective states. In contrast, selective kappa opioid receptor antagonists have antidepressant- and anxiolytic-like effects, stimulating interest in their therapeutic potential. The prototypical kappa opioid receptor antagonists (e.g., norBNI, JDTic) have an exceptionally long duration of action that complicates their use in humans, particularly in tests to establish safety. This study was designed to test dose- and time-course effects of novel kappa opioid receptor antagonists with the goal of identifying short-acting lead compounds for future medication development. METHODS: We screened 2 novel, highly selective kappa opioid receptor antagonists (CYM-52220 and CYM-52288) with oral efficacy in the warm water tail flick assay in rats to determine initial dose and time course effects. For comparison, we tested existing kappa opioid receptor antagonists JDTic and LY-2456302 (also known as CERC-501 or JNJ-67953964). RESULTS: In the tail flick assay, the rank order of duration of action for the antagonists was LY-2456302 < CYM-52288 < CYM-52220 << JDTic. Furthermore, LY-2456302 blocked the depressive (anhedonia-producing) effects of the kappa opioid receptor agonist U50,488 in the intracranial self-stimulation paradigm, albeit at a higher dose than that needed for analgesic blockade in the tail flick assay. CONCLUSIONS: These results suggest that structurally diverse kappa opioid receptor antagonists can have short-acting effects and that LY-2456302 reduces anhedonia as measured in the intracranial self-stimulation test.


Assuntos
(trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/farmacologia , Analgésicos não Narcóticos/farmacologia , Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Benzamidas/farmacologia , Antagonistas de Entorpecentes/farmacologia , Piperidinas/farmacologia , Pirrolidinas/farmacologia , Receptores Opioides kappa/antagonistas & inibidores , Tetra-Hidroisoquinolinas/farmacologia , (trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/administração & dosagem , Analgésicos não Narcóticos/administração & dosagem , Animais , Ansiolíticos/administração & dosagem , Antidepressivos/administração & dosagem , Benzamidas/administração & dosagem , Desenvolvimento de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Masculino , Antagonistas de Entorpecentes/administração & dosagem , Piperidinas/administração & dosagem , Pirrolidinas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Receptores Opioides kappa/agonistas , Tetra-Hidroisoquinolinas/administração & dosagem
4.
Drug Deliv Transl Res ; 8(2): 375-386, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28462499

RESUMO

Lipid-based drug delivery systems, a well-tolerated class of formulations, have been evaluated extensively to enhance the bioavailability of poorly soluble drugs. However, it has been difficult to predict the in vivo performance of lipid dosage forms based on conventional in vitro techniques such as cell monolayer permeability studies because of the complexity of the gastrointestinal processing of lipid formulations. In the current study, we explored the feasibility of coupling Caco-2 and Madin-Darby canine kidney monolayer permeability studies with lipolysis, a promising in vitro technique to evaluate lipid systems. A self-emulsifying lipid delivery system was formulated using a blend of oil (castor oil), surfactant (Labrasol® or PL497), and co-surfactant (lecithin). Formulations demonstrating high drug solubility and rapid self-emulsification were selected to study the effect of lipolysis on in vitro cell permeability. Lipolysis of the formulations was carried out using pancreatin as the digestive enzyme. All the digested formulations compromised monolayer integrity as indicated by lowered trans-epithelial electrical resistance (TEER) and enhanced Lucifer yellow (LY) permeability. Further, the changes in TEER value and LY permeability were attributable to the digestion products of the formulation rather than the individual lipid excipients, drug, digestion enzyme, or the digestion buffer. The digested formulations were fractionated into pellet, oily phase, and aqueous phase, and the effect of each of these on cell viability was examined. Interestingly, the aqueous phase, which is considered important for in vivo drug absorption, was responsible for cytotoxicity. Because lipid digestion products lead to disruption of cell monolayer, it may not be appropriate to combine lipolysis with cell monolayer permeability studies. Additional in vivo studies are needed to determine any potential side effects of the lipolysis products on the intestinal permeability barrier, which could determine the suitability of lipid-based systems for oral drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Acridinas/administração & dosagem , Acridinas/química , Administração Oral , Animais , Células CACO-2 , Óleo de Rícino/administração & dosagem , Óleo de Rícino/química , Sobrevivência Celular/efeitos dos fármacos , Cães , Excipientes/administração & dosagem , Excipientes/química , Humanos , Lecitinas/administração & dosagem , Lecitinas/química , Lipólise , Células Madin Darby de Rim Canino , Permeabilidade , Tensoativos/administração & dosagem , Tensoativos/química , Tetra-Hidroisoquinolinas/administração & dosagem , Tetra-Hidroisoquinolinas/química
5.
Anticancer Res ; 37(8): 4139-4146, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28739698

RESUMO

BACKGROUND/AIM: Eribulin mesylate, also called Halaven® (HAL), was recently developed as a microtubule-targeting drug and is used in the clinic for resistant or metastatic cancer. Previously, we showed that P-glycoprotein (P-gp)-overexpressing KBV20C oral cancer cells are highly resistant to HAL compared to sensitive KB cells. This qualitative study was designed to identify specific P-gp inhibitors that increase the sensitivity of highly resistant cancer cells to HAL. MATERIALS AND METHODS: In order to identify functional P-gp inhibitors, HAL-treated KBV20C cells were co-treated with P-gp inhibitors, verapamil, elacridar, cyclosporine A, mitotane, piperine, fumagillin, curcumin, indomethacin, probenecid, sulindac, tesmilifene, and C-4. We then evaluated which P-gp inhibitors required a low dose to sensitize KBV20C cells to HAL. We also determined whether a low dose of a P-gp inhibitor could inhibit P-gp efflux pumping. RESULTS: We found that cyclosporine A sensitized HAL-treated KBV20C cells at a low dose, whereas verapamil, another first-generation P-gp inhibitor, required a dose that was nearly 10-fold higher. We also found that the natural products, piperine and mitotane, sensitized KBV20C cells to HAL co-treatment. Interestingly, we found that elacridar, a third-generation P-gp inhibitor, sensitized HAL-treated cells at a low dose. Elacridar required approximately a 500-fold lower dose than that of verapamil to exert a similar effect. All inhibitors showed P-gp inhibitory activity that correlated with sensitivity to HAL. CONCLUSION: These results suggest that highly HAL-resistant cancer cells can be sensitized with cyclosporine A or elacridar, specific P-gp inhibitors that exert their effects at a low dose. These findings provide important information regarding the sensitization of highly HAL-resistant cells with selective P-gp inhibitors and indicate that elacridar may be used to treat such highly HAL-resistant cancer cells.


Assuntos
Acridinas/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/genética , Furanos/administração & dosagem , Cetonas/administração & dosagem , Neoplasias Bucais/tratamento farmacológico , Tetra-Hidroisoquinolinas/administração & dosagem , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Neoplasias Bucais/genética , Neoplasias Bucais/patologia
6.
Curr Treat Options Oncol ; 18(6): 34, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28534249

RESUMO

OPINION STATEMENT: Trabectedin and eribulin are two agents that have been recently approved for the treatment of specific soft tissue sarcoma subtypes. They have proved to be a much-needed line of additional treatment for patients with these rare tumors, but their activity remains admittedly modest in most cases. Further exploitation of these novel agents is likely to require a more granular understanding of the salient mechanisms of action. For example, if as some studies suggest, eribulin derives its benefit from restructuring of tumor vasculature to improve efficacy of subsequent lines of therapy, then patients may benefit from its use earlier in the treatment pathway. The sequencing of trabectedin with other agents is also worth examining. In a disease like myxoid liposarcoma, consideration should be given to using trabectedin before other salvage regimens like gemcitabine and docetaxel, given its tolerability and excellent efficacy against this sarcoma subtype. Also, to be further investigated is the use of trabectedin in sarcoma subtypes which were excluded from the phase III study, but in which activity has been documented in earlier trials and subsequent reports. Combinations of trabectedin with other agents, particularly doxorubicin, have been explored, but the data to date do not support the routine use of these regimens.


Assuntos
Antineoplásicos/uso terapêutico , Dioxóis/uso terapêutico , Furanos/uso terapêutico , Cetonas/uso terapêutico , Sarcoma/tratamento farmacológico , Tetra-Hidroisoquinolinas/uso terapêutico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ensaios Clínicos como Assunto , Dioxóis/administração & dosagem , Dioxóis/efeitos adversos , Avaliação Pré-Clínica de Medicamentos , Furanos/administração & dosagem , Furanos/efeitos adversos , Humanos , Cetonas/administração & dosagem , Cetonas/efeitos adversos , Terapia de Alvo Molecular , Sarcoma/diagnóstico , Sarcoma/metabolismo , Sarcoma/mortalidade , Tetra-Hidroisoquinolinas/administração & dosagem , Tetra-Hidroisoquinolinas/efeitos adversos , Trabectedina , Resultado do Tratamento
7.
Mil Med ; 180(7): e847-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26126260

RESUMO

Rhabdomyolysis is a painful and potentially life-threatening injury in which muscle breaks down in response to an insult. In this case report, we describe the clinical course of a 22-year-old man who developed paraspinal muscle rhabdomyolysis and possible compartment syndrome in association with strenuous activity and the ingestion of an exercise supplement containing the stimulant higenamine. Although he did not experience any renal damage, he did experience a high level of pain acutely and for the next 4 months. A history of exercise supplement intake should increase the index of suspicion for rhabdomyolysis when a patient presents with moderate to severe muscle pain, even if the muscle group is not in a classic location for rhabdomyolysis.


Assuntos
Alcaloides/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Músculos Paraespinais/patologia , Rabdomiólise/induzido quimicamente , Tetra-Hidroisoquinolinas/efeitos adversos , Administração Oral , Alcaloides/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Humanos , Imageamento por Ressonância Magnética , Masculino , Músculos Paraespinais/efeitos dos fármacos , Rabdomiólise/diagnóstico , Tetra-Hidroisoquinolinas/administração & dosagem , Adulto Jovem
8.
Health Technol Assess ; 19(7): 1-480, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25626481

RESUMO

BACKGROUND: Ovarian cancer is the fifth most common cancer in the UK, and the fourth most common cause of cancer death. Of those people successfully treated with first-line chemotherapy, 55-75% will relapse within 2 years. At this time, it is uncertain which chemotherapy regimen is more clinically effective and cost-effective for the treatment of recurrent, advanced ovarian cancer. OBJECTIVES: To determine the comparative clinical effectiveness and cost-effectiveness of topotecan (Hycamtin(®), GlaxoSmithKline), pegylated liposomal doxorubicin hydrochloride (PLDH; Caelyx(®), Schering-Plough), paclitaxel (Taxol(®), Bristol-Myers Squibb), trabectedin (Yondelis(®), PharmaMar) and gemcitabine (Gemzar(®), Eli Lilly and Company) for the treatment of advanced, recurrent ovarian cancer. DATA SOURCES: Electronic databases (MEDLINE(®), EMBASE, Cochrane Central Register of Controlled Trials, Health Technology Assessment database, NHS Economic Evaluations Database) and trial registries were searched, and company submissions were reviewed. Databases were searched from inception to May 2013. METHODS: A systematic review of the clinical and economic literature was carried out following standard methodological principles. Double-blind, randomised, placebo-controlled trials, evaluating topotecan, PLDH, paclitaxel, trabectedin and gemcitabine, and economic evaluations were included. A network meta-analysis (NMA) was carried out. A de novo economic model was developed. RESULTS: For most outcomes measuring clinical response, two networks were constructed: one evaluating platinum-based regimens and one evaluating non-platinum-based regimens. In people with platinum-sensitive disease, NMA found statistically significant benefits for PLDH plus platinum, and paclitaxel plus platinum for overall survival (OS) compared with platinum monotherapy. PLDH plus platinum significantly prolonged progression-free survival (PFS) compared with paclitaxel plus platinum. Of the non-platinum-based treatments, PLDH monotherapy and trabectedin plus PLDH were found to significantly increase OS, but not PFS, compared with topotecan monotherapy. In people with platinum-resistant/-refractory (PRR) disease, NMA found no statistically significant differences for any treatment compared with alternative regimens in OS and PFS. Economic modelling indicated that, for people with platinum-sensitive disease and receiving platinum-based therapy, the estimated probabilistic incremental cost-effectiveness ratio [ICER; incremental cost per additional quality-adjusted life-year (QALY)] for paclitaxel plus platinum compared with platinum was £24,539. Gemcitabine plus carboplatin was extendedly dominated, and PLDH plus platinum was strictly dominated. For people with platinum-sensitive disease and receiving non-platinum-based therapy, the probabilistic ICERs associated with PLDH compared with paclitaxel, and trabectedin plus PLDH compared with PLDH, were estimated to be £25,931 and £81,353, respectively. Topotecan was strictly dominated. For people with PRR disease, the probabilistic ICER associated with topotecan compared with PLDH was estimated to be £324,188. Paclitaxel was strictly dominated. LIMITATIONS: As platinum- and non-platinum-based treatments were evaluated separately, the comparative clinical effectiveness and cost-effectiveness of these regimens is uncertain in patients with platinum-sensitive disease. CONCLUSIONS: For platinum-sensitive disease, it was not possible to compare the clinical effectiveness and cost-effectiveness of platinum-based therapies with non-platinum-based therapies. For people with platinum-sensitive disease and treated with platinum-based therapies, paclitaxel plus platinum could be considered cost-effective compared with platinum at a threshold of £30,000 per additional QALY. For people with platinum-sensitive disease and treated with non-platinum-based therapies, it is unclear whether PLDH would be considered cost-effective compared with paclitaxel at a threshold of £30,000 per additional QALY; trabectedin plus PLDH is unlikely to be considered cost-effective compared with PLDH. For patients with PRR disease, it is unlikely that topotecan would be considered cost-effective compared with PLDH. Randomised controlled trials comparing platinum with non-platinum-based treatments might help to verify the comparative effectiveness of these regimens. STUDY REGISTRATION: This study is registered as PROSPERO CRD42013003555. FUNDING: The National Institute for Health Research Health Technology Assessment programme.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Custos de Cuidados de Saúde , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/economia , Análise Custo-Benefício , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/economia , Dioxóis/administração & dosagem , Dioxóis/efeitos adversos , Intervalo Livre de Doença , Método Duplo-Cego , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Doxorrubicina/economia , Feminino , Humanos , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Ovarianas/economia , Neoplasias Ovarianas/mortalidade , Paclitaxel/administração & dosagem , Paclitaxel/economia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/economia , Anos de Vida Ajustados por Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Análise de Sobrevida , Tetra-Hidroisoquinolinas/administração & dosagem , Tetra-Hidroisoquinolinas/efeitos adversos , Topotecan/administração & dosagem , Topotecan/economia , Trabectedina , Resultado do Tratamento , Reino Unido , Gencitabina
9.
Neurotox Res ; 25(4): 323-34, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24065621

RESUMO

Oxidative stress is a major contributing factor in a range of brain pathologies and in the etiology of depression. 1-Methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ) is an endogenous substance which is present in the mammalian brain and exhibits neuroprotective, and monoamine oxidase (MAO)-inhibiting properties. In the present study, in order to investigate the potential role of 1MeTIQ as an antidepressant, we tested antidepressant-like effects of 1MeTIQ in comparison with desipramine (a classic antidepressant) in the forced swimming test (FST), and using HPLC methodology, we measured the concentrations of monoamines (dopamine, noradrenaline, serotonin) and the rate of their metabolism. 1MeTIQ given alone as well as in combination with desipramine produced an antidepressant-like effect and decreased the immobility time in the FST. Neurochemical data have shown that 1MeTIQ like desipramine, activated the noradrenergic system. However, the mechanism of action of 1MeTIQ is broader than the actions of desipramine, and 1MeTIQ inhibits the MAO-dependent oxidation of dopamine and serotonin in all investigated structures. We can conclude that 1MeTIQ exhibits antidepressant-like activity in the FST in the rat. The mechanism of its antidepressant action differs from desipramine and seems to be mostly associated with the inhibition of the catabolism of monoamines and their increased concentrations in the brain. 1MeTIQ seems to be very beneficial from the clinical point of view as a reversible MAO inhibitor with a significant antidepressant effects.


Assuntos
Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Depressão/metabolismo , Tetra-Hidroisoquinolinas/farmacologia , Animais , Antidepressivos/administração & dosagem , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Desipramina/farmacologia , Dopamina/administração & dosagem , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Inibidores da Monoaminoxidase/administração & dosagem , Inibidores da Monoaminoxidase/farmacologia , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Norepinefrina/metabolismo , Oxirredução/efeitos dos fármacos , Ratos , Ratos Wistar , Serotonina/metabolismo , Natação , Análise e Desempenho de Tarefas , Tetra-Hidroisoquinolinas/administração & dosagem , Resultado do Tratamento
10.
Lipids Health Dis ; 12: 148, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24139127

RESUMO

BACKGROUND: Higenamine, also known as norcoclaurine, is an herbal constituent thought to act as a beta-2 adrenergic receptor agonist-possibly stimulating lipolysis. It was the purpose of this study to determine the impact of a higenamine-based dietary supplement on plasma free fatty acids and energy expenditure following acute oral ingestion. METHODS: Sixteen healthy subjects (8 men; 26.1 ± 2.5 yrs; 8 women 22.4 ± 3.1 yrs) ingested a dietary supplement containing a combination of higenamine, caffeine (270 mg), and yohimbe bark extract or a placebo, on two separate occasions in a double-blind, randomized, cross-over design, separated by 6-8 days. Blood samples were collected immediately before ingestion, and at 30, 60, 120, and 180 minutes post ingestion, and analyzed for plasma free fatty acids (FFA) and glycerol. Breath samples were collected at the same times for a measure of kilocalorie expenditure and respiratory exchange ratio (RER) using indirect calorimetry. Heart rate and blood pressure were recorded at all times. Data collection occurred in the morning following a 10 hour overnight fast. RESULTS: A condition effect was noted for both FFA (p < 0.0001) and kilocalorie expenditure (p = 0.001), with values higher for supplement compared to placebo at 60, 120, and 180 minutes post ingestion. No statistically significant effects were noted for glycerol or RER (p > 0.05). A condition effect was noted for heart rate (p = 0.03) and systolic blood pressure (p < 0.0001), with values higher for supplement compared to placebo. CONCLUSION: Ingestion of a higenamine-based dietary supplement stimulates lipolysis and energy expenditure, as evidenced by a significant increase in circulating FFA and kilocalorie expenditure. The same supplement results in a moderate increase in heart rate (~3 bpm) and systolic blood pressure (~12 mmHg), which is consistent with previous studies evaluating moderate doses of caffeine and yohimbine, suggesting that higenamine contributes little to the increase in these hemodynamic variables. These findings are in reference to young, healthy and active men and women.


Assuntos
Alcaloides/administração & dosagem , Cafeína/administração & dosagem , Suplementos Nutricionais , Metabolismo Energético/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Tetra-Hidroisoquinolinas/administração & dosagem , Ioimbina/administração & dosagem , Adulto , Pressão Sanguínea/efeitos dos fármacos , Testes Respiratórios , Estudos Cross-Over , Método Duplo-Cego , Combinação de Medicamentos , Metabolismo Energético/fisiologia , Ácidos Graxos não Esterificados/sangue , Feminino , Glicerol/sangue , Voluntários Saudáveis , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino
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