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1.
Drug Des Devel Ther ; 14: 961-967, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184565

RESUMO

OBJECTIVE: This study aimed to quantify the amount of perindopril and its active metabolite perindoprilat present in breast milk and corresponding maternal and infant plasma concentrations. DESIGN: Prospective, longitudinal, observational. SETTING: Tertiary specialist paediatric and obstetric hospital in Adelaide, South Australia. POPULATION: Breastfeeding women actively treated with perindopril for hypertensive disorders postpartum. METHODS: Eight breast milk samples and a single plasma sample were collected from each participant over a 24 hrs period, and plasma samples were taken from eligible breastfed infants. Breast milk and plasma concentrations of perindopril and perindoprilat were analysed using a validated Liquid Chromatography tandem-Mass Spectrometry (LC-MS/MS) method. MAIN OUTCOME MEASURES: Mean breast milk concentrations of perindopril and perindoprilat, Relative Infant Dose (RID) <10%, and Theoretical Infant Dose (TID). RESULTS: Ten women and three infants participated in the study. The mean concentration of perindopril in breast milk for each participant ranged from 0.003 to 1.2 ng/mL and perindoprilat 0.2-36 ng/mL. RID for perindopril was 0.0005-0.2% and perindoprilat 0.03-4.6%. TID for perindopril was 0.00045-0.18 µg/kg/day and perindoprilat 0.032-5.4 µg/kg/day. Infant plasma levels for perindopril ranged from 0.44 to 1.12 ng/mL and perindoprilat undetectable - 10.14 ng/mL. Maternal reports described normal infant growth and development. CONCLUSION: Infant exposure to perindopril and perindoprilat through breast milk is low. However, some infants were found to have plasma perindoprilat concentrations consistent with pharmacodynamic effects. Perindopril may be used in mothers of healthy term infants, provided the infant is carefully monitored.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/sangue , Leite Humano/química , Perindopril/sangue , Adulto , Aleitamento Materno/efeitos adversos , Feminino , Humanos , Indóis/sangue , Indóis/farmacocinética , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
2.
Drug Metab Dispos ; 45(5): 569-575, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28188296

RESUMO

The aim of this study was to determine the effects of garlic and ginkgo herbal extracts on the pharmacokinetics of the P-glycoprotein (P-gp)/organic anion-transporting polypeptides (Oatps) substrate fexofenadine. Male rats were dosed orally with garlic (120 mg/kg), ginkgo (17 mg/kg), St. John's wort (SJW; 1000 mg/kg; positive control), or Milli-Q water for 14 days. On day 15, rats either were administered fexofenadine (orally or i.v.), had their livers isolated and perfused with fexofenadine, or had their small intestines divided into four segments (SI-SIV) and analyzed for P-gp and Oatp1a5. In vivo, SJW increased the clearance of i.v. administered fexofenadine by 28%. Garlic increased the area under the curve0-∞ and maximum plasma concentration of orally administered fexofenadine by 47% and 85%, respectively. Ginkgo and SJW had no effect on the oral absorption of fexofenadine. In the perfused liver, garlic, ginkgo, and SJW increased the biliary clearance of fexofenadine with respect to perfusate by 71%, 121%, and 234%, respectively. SJW increased the biliary clearance relative to the liver concentration by 64%. The ratio of liver to perfusate concentrations significantly increased in all treated groups. The expression of Oatp1a5 in SI was increased by garlic (88%) and SJW (63%). There were no significant changes in the expression of P-gp. Induction of intestinal Oatp1a5 by garlic may explain the increased absorption of orally administered fexofenadine. Ginkgo had no effect on the expression of intestinal P-gp or Oatp1a5. A dual inductive effect by SJW on opposing intestinal epithelial transport by Oatp1a5 and P-gp remains a possibility.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Alho/química , Ginkgo biloba/química , Hypericum/química , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Extratos Vegetais/farmacologia , Terfenadina/análogos & derivados , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Administração Oral , Animais , Interações Medicamentosas , Injeções Intravenosas , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Masculino , Transportadores de Ânions Orgânicos Sódio-Independentes/genética , Perfusão , Extratos Vegetais/isolamento & purificação , Ratos , Especificidade por Substrato , Terfenadina/administração & dosagem , Terfenadina/sangue , Terfenadina/farmacocinética , Distribuição Tecidual
3.
Sci Total Environ ; 565: 384-391, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27179320

RESUMO

Analysis of municipal wastewater for drug metabolites can reveal the scale of drug use within communities. An Australian city with a population of 1.2million inhabitants was assessed for 4 stimulants: cocaine, methamphetamine, 3.4-methylenedioxymethamphetamine (MDMA) and amphetamine; 6 opioids: codeine, morphine, heroin, fentanyl, oxycodone and methadone; 11 new psychoactive substances (NPS); benzylpiperazine (BZP), trifluoromethylphenylpiperazine (TFMPP), methcathinone, methylone, mephedrone, methylenedioxypyrovalerone (MDPV), alpha pyrrolidinopentiophenone (alpha-PVP), paramethoxyamphetamine (PMA), 25C-NBOMe, 25B-NBOMe, 25I-NBOMe; and cannabis, for up to four years between December 2011 and December 2015. Temporal trends revealed increasing usage rates of methamphetamine, cocaine, oxycodone, and fentanyl, while decreasing rates of use were observed for MDMA, BZP and methylone. Use of other opioids and cannabis was generally stable across years, while use of new psychoactive substances fluctuated without an apparent direction. Opioids and cannabis were used at a consistent level through the course of the week, while use of stimulants and some NPS increased on the weekend. Seasonal differences in use were observed for MDMA and cannabis (p$_amp_$lt;0.05) where, on average, MDMA use was approximately 90% higher in December than in other months and cannabis use was approximately 45% lower in each February. Residual month-to-month variability measures on trend-free data showed NPS use had higher variability than the stimulants and opioids. Frequent wastewater sampling and analysis over prolonged periods has yielded valuable insights into long-term drug use trends, in some instances revealed important within-year trends, and demonstrated the differing patterns of use of drugs on weekends compared to weekdays.


Assuntos
Analgésicos Opioides/análise , Monitoramento Ambiental/métodos , Drogas Ilícitas/análise , Vigilância da População/métodos , Detecção do Abuso de Substâncias/tendências , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Cidades , Previsões , Humanos , Austrália do Sul/epidemiologia
4.
Drug Test Anal ; 8(7): 702-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26198173

RESUMO

Wastewater analysis, the chemical analysis of municipal sewage, is fast becoming the technique of choice to monitor changes in community consumption of a range of compounds over time. Currently wastewater analyses which estimate tobacco consumption focus on the major alkaloid nicotine and its urinary metabolite, cotinine. As nicotine is also present in replacement therapies such as nicotine gum and patches, this analysis is not specific and hence does not truly reflect the harmful consumption of tobacco. Two alkaloids - anabasine and anatabine - which are specific to dried tobacco, were assessed as biomarkers for tobacco consumption in wastewater, together with nicotine and cotinine. Consequently, solid phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS) methods for the detection of anabasine, anatabine, nicotine, and cotinine in municipal wastewater were validated. All compounds were detected in wastewater extracts and found to have satisfactory recovery, accuracy, precision, and stability in wastewater. Daily flow volume and catchment population of the wastewater facility were used to estimate normalized consumption figures of mg/day/1000 people for composite samples collected over one week, in an application of the method. Anabasine and anatabine were found to be suitable wastewater biomarkers of tobacco and can be used to assess tobacco consumption of communities via wastewater analysis. Application of this methodology can be used to collect temporal consumption data which could be used to determine the efficacy of tobacco reduction strategies. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Alcaloides/análise , Anabasina/análise , Cotinina/análise , Nicotina/análise , Piridinas/análise , Uso de Tabaco/epidemiologia , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida/métodos , Humanos , Limite de Detecção , Espectrometria de Massas/métodos , Extração em Fase Sólida/métodos
5.
Sci Total Environ ; 536: 331-337, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26225740

RESUMO

Levels of community drug use are usually described by national surveys; data relied upon by decision makers in health and law enforcement. In recent years the analysis of wastewater for drugs and their metabolites has become prominent. Both methods convey unique drug use information. This paper demonstrates differences arising from the two approaches, using methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and cocaine data from the state of South Australia. The proportion of people using each drug, obtained from three prominent drug surveys, was compared with estimates of total community drug use derived by wastewater analysis. Temporal trends were compared for available years of the surveys and wastewater analysis from 2010 to 2013. Wastewater results showed methamphetamine to be the most prevalent stimulant in Adelaide, South Australia, with an average of 24.4±1.7 doses per day per 1000 inhabitants for 2013, while consumption of MDMA and cocaine were much lower at 0.52±0.12 and 0.42±0.06 doses per day per 1000 inhabitants, respectively. Survey data typically had MDMA as the most used stimulant on a proportion of the population basis. The difference in magnitude of drug use between MDMA and methamphetamine was also less apparent. Temporal trends of the proportion of the population using a drug by surveys did not generally reflect total use within the community which was observed by wastewater analysis. Survey data are excellent for describing users demographically. However, discrepancies between the proportion of the population who are users and the magnitude of drug use can lead to misrepresentation of the overall scale of use. The results from this study indicate methamphetamine was used to a much greater extent than suggested by the surveys. Together, wastewater analysis and survey data give a comprehensive view of the drug problem enabling more informed decisions on drug policy.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Águas Residuárias/química , Poluentes Químicos da Água/análise , Austrália do Sul/epidemiologia , Detecção do Abuso de Substâncias/métodos , População Urbana
6.
J Chem Neuroanat ; 64-65: 20-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25681296

RESUMO

Parkinson's disease is characterised pathologically by a relatively selective death of dopaminergic neurons in the substantia nigra of the brain. The vulnerability of these neurons appears to be linked to the pigment neuromelanin. However, as yet there is limited understanding behind the mechanisms of this disease process. Complications arise due to the difficulty in obtaining appreciable quantities of neuromelanin. Furthermore, an appropriate model for studying neuromelanin has not been identified. To date there has been many studies looking at the binding and chemical characteristics of neuromelanin. However, a range of different synthetic and organic melanins have been used as models and leading to many varied conclusions being drawn. Therefore, the aim of this review is to present Sepia melanin as the most appropriate study model for the binding characteristics of neuromelanin. Considerations included chemical structure, surface characteristics and structural features of both synthetic and organic melanins.


Assuntos
Melaninas/toxicidade , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/fisiopatologia , Sepia/química , Animais , Modelos Animais de Doenças , Melaninas/química , Melaninas/metabolismo
7.
Sci Total Environ ; 487: 621-8, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24300482

RESUMO

Wastewater analysis has the potential to provide objective information on community drug use. Introducing a population biomarker (PB) in the sample analysis may significantly reduce errors in the back-calculation associated with population estimation and wastewater volume measurement. A number of potential PBs have been suggested but no systematic evaluation has been conducted so far. This study evaluated the eligibility of the previously suggested PB candidates (creatinine, cholesterol, coprostanol and cotinine) as well as three new ones (cortisol, androstenedione and 5-hydroxyindoleacetic acid (5-HIAA)) using five criteria. We assessed the quantification method, affinity to particulate matter and stability of candidates in wastewater, as well as the constancy of inter-day excretion and correlation between excretion and census population. All PB candidates were quantifiable in wastewater. Cholesterol and coprostanol were eliminated from further consideration due to affinity to particulate matters in the wastewater. Creatinine, cortisol and androstenedione were disqualified for stability reasons. On a population scale, both cotinine and 5-HIAA were excreted (RSD=8.01 ± 1.13% and 10.20 ± 0.89%, respectively) at a constant rate and concentrations of each correlated well with the census population (r=0.9809 and 0.9442, respectively). Overall, both cotinine and 5-HIAA are eligible PBs, but the neurotransmitter metabolite 5-HIAA may be more suitable for international comparisons.


Assuntos
Biomarcadores/análise , Drogas Ilícitas/análise , Detecção do Abuso de Substâncias/métodos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Cotinina , Ácido Hidroxi-Indolacético , Eliminação de Resíduos Líquidos
8.
Mol Autism ; 4(1): 42, 2013 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-24188502

RESUMO

BACKGROUND: A recent report indicated that numbers of Sutterella spp. are elevated in gastrointestinal biopsies taken from children with autism spectrum disorder (ASD). We have recently reported changes in the numbers of some bacteria within the stool of ASD children, and now examine whether numbers of Sutterella spp. and some other mucosa-associated bacteria linked with gastrointestinal disease (Ruminococcus gnavus and Ruminococcus torques) are also altered in the stool of these children. FINDINGS: We show that numbers of Sutterella spp. are elevated in feces of ASD children relative to controls, and that numbers of R. torques are higher in the children with ASD with a reported functional gastrointestinal disorder than those without such a disorder. CONCLUSIONS: We show further evidence of changes in the gut microbiota of children with ASD and confirm that the abundance of Sutterella spp. is altered in stool.

9.
Biomarkers ; 16(7): 537-52, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22022826

RESUMO

CONTEXT: Autism is a complex, heterogeneous neurodevelopmental condition with a strong genetic component potentially impacted by various environmental factors influencing susceptibility. There are no reliable laboratory tests available to confirm an autism diagnosis. OBJECTIVE: To examine the published literature and identify putative urinary biomarkers of autism. METHODS: A comprehensive literature search was conducted using electronic bibliographic databases. RESULTS: Putative autism biomarkers were identified that could be categorized according to the key theories that exist regarding the etiology of autism: gastrointestinal factors, immune dysregulation, heavy metal toxicity, neurotransmitter abnormalities, and oxidative stress. CONCLUSION: There is scope for specific urinary biomarkers to be useful for identification of autistic metabolic phenotypes.


Assuntos
Biomarcadores/urina , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Transtornos Globais do Desenvolvimento Infantil/urina , Criança , Glicina/análogos & derivados , Glicina/urina , Humanos , Neopterina/urina , Neurotransmissores/urina , Peptídeos/urina , Porfirinas/urina , Sensibilidade e Especificidade
10.
Appl Environ Microbiol ; 77(18): 6718-21, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21784919

RESUMO

Gastrointestinal disturbance is frequently reported for individuals with autism. We used quantitative real-time PCR analysis to quantify fecal bacteria that could influence gastrointestinal health in children with and without autism. Lower relative abundances of Bifidobacteria species and the mucolytic bacterium Akkermansia muciniphila were found in children with autism, the latter suggesting mucus barrier changes.


Assuntos
Transtorno Autístico/complicações , Bifidobacterium/isolamento & purificação , Dispepsia/epidemiologia , Fezes/microbiologia , Verrucomicrobia/isolamento & purificação , Carga Bacteriana , Bifidobacterium/genética , Criança , Dispepsia/microbiologia , Humanos , Muco/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Verrucomicrobia/genética
11.
Phytochemistry ; 72(14-15): 1883-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21641623

RESUMO

Three prenylated flavonoids 5,7,4'-trihydroxy-3'(3-methylbut-2-enyl)-3-methoxy flavone, 5,7-dihydroxy-3'(3-methylbut-2-enyl)-3,4'-dimethoxy flavone and 5,7,4'-trihydroxy-3',5'(3-methylbuyt-2-enyl)-3-methoxy flavone together with three other known flavonoids were isolated from the medicinal plant Dodonaea polyandra. The plant is used in the traditional medicine system of Northern Kaanju people of Cape York Peninsula, Queensland, Australia. The extracts studied have previously been found to possess anti-inflammatory activity. Successive fractionation of leaf and stem extracts by column and high performance liquid chromatography led to the isolation of these compounds. Their structures were determined using a number of spectroscopic techniques including 1D and 2D NMR and high resolution mass spectroscopy. The structural elucidation is reported herein accompanied by full ¹H and ¹³C NMR spectroscopic data. Spectroscopic data of known compounds was in agreement with that previously reported in literature.


Assuntos
Flavonoides/isolamento & purificação , Extratos Vegetais/química , Sapindaceae/química , Flavonoides/química , Medicina Tradicional , Estrutura Molecular , Folhas de Planta/química , Caules de Planta/química , Plantas Medicinais , Prenilação , Queensland
12.
J Nat Prod ; 74(4): 650-7, 2011 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-21381684

RESUMO

Four new benzoyl ester clerodane diterpenoids, 15,16-epoxy-8α-(benzoyloxy)methylcleroda-3,13(16),14-trien-18-oic acid (1), 15,16-epoxy-8α-(benzoyloxy)methyl-2α-hydroxycleroda-3,13(16),14-trien-18-oic acid (2), 15,16-epoxy-8α-(benzoyloxy)methyl-2-oxocleroda-3,13(16),14-trien-18-oic acid (3), and 15,16-epoxy-2α-benzoyloxycleroda-3,13(16),14-trien-18-oic acid (4), have been isolated from the leaves and stems of Dodonaea polyandra. The anti-inflammatory activities of compounds 1, 2, and 4 were evaluated by means of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema. Compounds 2 and 4 exhibited maximum inhibition of inflammation (70-76%) at doses of 0.22 and 0.9 µmol/ear, respectively. Modest activity (~45% inhibition) was maintained at nanomole/ear doses.


Assuntos
Anti-Inflamatórios não Esteroides/isolamento & purificação , Diterpenos Clerodânicos/isolamento & purificação , Sapindaceae/química , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Austrália , Modelos Animais de Doenças , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/farmacologia , Orelha/patologia , Edema/induzido quimicamente , Camundongos , Estrutura Molecular , Folhas de Planta/química , Caules de Planta/química , Acetato de Tetradecanoilforbol/farmacologia
13.
Mutat Res ; 721(2): 119-26, 2011 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-21295156

RESUMO

Azoxymethane (AOM) is a methylating agent capable of inducing mutations in DNA by forming adducts with DNA bases. It has been used to understand the mechanisms involved in colon carcinogenesis. Of the adducts formed in response to AOM, O(6)-methyl-2'-deoxy-guanosine (O(6)-mdGua) is the most mutagenic. Based on studies in rodents of the abundance and persistence of DNA adducts in various tissues after treatment with alkylating agents, previous results suggest, as a generalization, that the longer O(6)-mdGua adducts remain unrepaired in the cells of a tissue, the greater the risk for tumorigenesis. To test this hypothesis, we have built on these studies, expanding the number of tissues in which O(6)-mdGua abundance and persistence were examined and correlating these data with tumour distribution and abundance in rats maintained for 26 weeks after the treatment with AOM. Our study revealed firstly the existence of groups of tissues that developed relatively large amounts (proximal and distal colon, proximal small intestine (SI), liver and kidney) and relatively low levels (stomach, distal SI, bladder, spleen, blood and lung) of O(6)-mdGua after AOM exposure. Secondly, while all tissues showed an increase in adduct levels at 6h after mutagen treatment and most showed a significant drop in adduct levels between 6h and 48h (stomach, proximal and distal SI, liver, spleen, blood and lung), one group of tissues displayed O(6)-mdGua levels that did not decrease at 48h (proximal and distal colon, kidney and bladder). Predictably, the colon displayed tumours 26 weeks after treatment. Interestingly, however, the proximal SI also displayed significant tumour formation at that time. Our findings demonstrate (1) a direct association between exposure to O(6)-mdGua and tumours of the distal colon and (2) a dissociation of the relationship between adduct clearance and tumorigenesis in the SI. This diversity of response in the gastrointestinal tract warrants further analysis.


Assuntos
Neoplasias do Colo/induzido quimicamente , Adutos de DNA/metabolismo , Desoxiguanosina/análogos & derivados , Trato Gastrointestinal/metabolismo , Alquilantes/metabolismo , Animais , Azoximetano/toxicidade , Desoxiguanosina/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Neoplasias Intestinais/induzido quimicamente , Intestino Delgado , Masculino , Metilação , Mutagênicos/toxicidade , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
14.
Autism Res ; 3(5): 268-72, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20589913

RESUMO

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that presents in the first three years of life. Currently, diagnosis of ASD is based on its behavioural manifestations, as laboratory diagnostic tests do not exist. Creatine deficiency syndrome (CDS) is one form of inborn error of metabolism where affected individuals have similar clinical features to individuals with ASD. Abnormal urinary creatine (CR) and guanidinoacetate (GAA) levels have been reported as biomarkers of CDS. We hypothesized that screening for abnormal levels of urinary CR and GAA in children with ASD may assist in identifying a subgroup of ASD individuals who can be managed with dietary interventions. Morning urine samples were collected from children with and without autism and analyzed for CR and GAA levels. Results showed there was no statistically significant difference in urinary CR:creatinine and GAA:creatinine between the children with ASD and sibling or unrelated controls. In conclusion, routine screening for abnormal urinary CR and GAA could be considered in ASD diagnostic protocols; however, individuals positive for CDS are likely to be rare in an ASD cohort.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/urina , Programas de Rastreamento/métodos , Biomarcadores/urina , Encefalopatias Metabólicas Congênitas/complicações , Encefalopatias Metabólicas Congênitas/diagnóstico , Encefalopatias Metabólicas Congênitas/urina , Criança , Transtornos Globais do Desenvolvimento Infantil/etiologia , Cromatografia Líquida de Alta Pressão/métodos , Creatina/deficiência , Creatina/urina , Feminino , Glicina/análogos & derivados , Glicina/urina , Humanos , Masculino , Deficiência Intelectual Ligada ao Cromossomo X/complicações , Deficiência Intelectual Ligada ao Cromossomo X/diagnóstico , Deficiência Intelectual Ligada ao Cromossomo X/urina , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/deficiência , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/urina , Síndrome , Espectrometria de Massas em Tandem/métodos
15.
Clin Exp Pharmacol Physiol ; 37(5-6): 593-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20082626

RESUMO

1. The aim of the present study was to investigate the mechanisms involved in the clearance of isosteviol using the rat isolated perfused liver. 2. Six livers from male Sprague-Dawley rats were perfused with 15.7 mumol isosteviol in a recirculating system. Perfusate and bile samples were collected for 60 min and the liver was collected at the end of the perfusion. All samples collected were incubated with alpha-glucuronidase. Isosteviol-glucuronide was determined as equivalent isosteviol. Isosteviol concentrations were determined using a previously developed liquid chromatography-tandem mass spectrometry method. The final isosteviol liver/perfusate (L/P), bile/liver (B/L) and isosteviol-glucuronide in bile/liver (B(G)/L(G)) ratios were determined. 3. Isosteviol has a high clearance (21.4 +/- 4.8 mL/min) from the perfusate, with a short half-life (13 +/- 4 min). alpha-Glucuronidase incubation revealed that isosteviol is conjugated in the liver and excreted into the bile. There was no isosteviol-glucuronide detected in perfusate samples. The total recovery of the rat isolated perfused liver system is 74 +/- 14% and glucuronidated isosteviol accounted for 23 +/- 4% of the administered dose. 4. In conclusion, we are the first to characterize the metabolism of isosteviol using rat isolated liver perfusion. Our results strongly suggest that the liver is the main organ of isosteviol elimination and that isosteviol is glucuronidated in the liver before it is excreted into the bile.


Assuntos
Diterpenos do Tipo Caurano/farmacocinética , Fígado/metabolismo , Animais , Bile/metabolismo , Cromatografia Líquida , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/metabolismo , Glucosídeos/metabolismo , Glucuronídeos/metabolismo , Glicosídeo Hidrolases/farmacologia , Técnicas In Vitro , Masculino , Taxa de Depuração Metabólica , Estrutura Molecular , Perfusão , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Distribuição Tecidual
16.
Biomarkers ; 14(8): 596-603, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19697973

RESUMO

An autism spectrum disorder (ASD) diagnosis is based on clinical behaviours as there are no validated biological diagnostic tools. Indolyl-3-acryloylglycine (IAG) is a chemical produced by gut microflora and there are conflicting reports as to whether urinary levels are elevated in children with ASD compared with controls. Urinary IAG levels in morning urine samples were statistically significantly higher in children with ASD whose caregivers reported the presence of chronic gastrointestinal (GI) disturbance than children with ASD without chronic GI disturbance. Urinary IAG, however, was not statistically significantly higher in children with ASD, compared with siblings or unrelated controls without ASD.


Assuntos
Transtorno Autístico/urina , Transtornos Globais do Desenvolvimento Infantil/urina , Gastroenteropatias/urina , Glicina/análogos & derivados , Transtorno Autístico/complicações , Biomarcadores , Criança , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Creatinina/urina , Feminino , Gastroenteropatias/complicações , Glicina/urina , Humanos , Masculino
17.
J Pharm Biomed Anal ; 48(3): 986-90, 2008 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-18701231

RESUMO

A sensitive liquid chromatographic-tandem mass spectrometric (LC-MS/MS) method was developed to investigate isosteviol pharmacokinetics in vivo. Isosteviol was extracted from plasma with hexane and 4% formic acid. A Phenomenex Synergi 2mu Fusion reversed phase analytical HPLC column (50 mm x 2.0 mm) equipped with a Synergi 2micro Fusion guard column was employed for chromatographic separations. The gradient mobile phase consisted of acetonitrile (ACN) and 20mM ammonium acetate at pH 6.5, starting at 20% ACN and ramping to 80% at 7 min, followed by 80% ACN for 1 min, then 20% ACN for 5 min. Negative SRM was used to monitor the m/z 317.1/317.1 and 317.3/317.3 transitions for isosteviol and 395.0/395.0 and 397.0/397.0 transitions for internal standard. The retention time of isosteviol was 9.2 min. The assay was linear over the range of 50-2,000 ng/mL. The accuracy of the method was in the range of 97-105%. Intra- and inter-day precisions were in the range of 1.5-4.6%. Isosteviol (4 mg/kg) was dosed intravenously and orally to Sprague-Dawley rats (n=6). Plasma samples were collected and analysed. Intravenous isosteviol has a distribution half-life of 35.7+/-9.0 min with the initial distribution volume of 68.1+/-9.4 mL. The total clearance, terminal half-life and steady-state volume of distribution were 1.25+/-0.12 mL/min, 150.6+/-50.5 min and 272.6+/-95.9 mL, respectively. The oral bioavailability of isosteviol was found to be 60.4+/-15.5%.


Assuntos
Cromatografia Líquida/métodos , Diterpenos do Tipo Caurano/farmacocinética , Edulcorantes/farmacocinética , Espectrometria de Massas em Tandem/métodos , Acetatos/química , Acetonitrilas/química , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Calibragem , Cromatografia Líquida/instrumentação , Diterpenos do Tipo Caurano/administração & dosagem , Diterpenos do Tipo Caurano/química , Estabilidade de Medicamentos , Congelamento , Meia-Vida , Concentração de Íons de Hidrogênio , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes/química , Edulcorantes/administração & dosagem , Edulcorantes/química , Espectrometria de Massas em Tandem/instrumentação , Temperatura
18.
J Chromatogr B Analyt Technol Biomed Life Sci ; 862(1-2): 205-12, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18187372

RESUMO

A liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed to quantify colistin in human plasma and urine, and perfusate and urine from the isolated perfused rat kidney (IPK). Solid phase extraction (SPE) preceded chromatography on a Synergi Fusion-RP column with a mobile phase of acetonitrile, water and acetic acid (80/19/1) at 0.2mL/min. Ions were generated using electrospray ionization and detected in the positive-ion mode. Multiple reaction monitoring was performed using precursor-product ion combinations. Calibration curves were linear from 0.028microg/mL (human plasma, IPK perfusate and urine)/0.056microg/mL (human urine) to 1.78microg/mL (all four media) for colistin A sulfate; corresponding values for colistin B sulfate were 0.016/0.032 to 1.01microg/mL. Accuracy and precision were within 10%. The LLOQ for colistin A sulfate was 0.028microg/mL in human plasma, IPK perfusate and urine and 0.056microg/mL in human urine; corresponding values for colistin B sulfate were 0.016 and 0.032microg/mL. The low sample volume, short analysis time and low LLOQ are ideal for pre-clinical and human pharmacokinetic studies of colistin.


Assuntos
Colistina/análise , Espectrometria de Massas em Tandem/métodos , Animais , Colistina/sangue , Colistina/urina , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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