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1.
Eur J Nutr ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727803

RESUMO

PURPOSE: Maternal high-fat diet (HF) programs obesity, metabolic dysfunction-associated steatotic liver disease (MASLD), hypertriglyceridemia, and hyperglycemia associated with increased endocannabinoid system (ECS) in the liver of adult male rat offspring. We hypothesized that maternal HF would induce sex specific ECS changes in the liver of newborn rats, prior to obesity onset, and maternal fish oil (FO) supplementation would reprogram the ECS and lipid metabolism markers preventing liver triglycerides (TG) accumulation. METHODS: Female rats received a control (CT) (10.9% fat) or HF (28.7% fat) diet 8 weeks prior to mating and during pregnancy. A subgroup of HF dams received 3% FO supplementation in the HF diet (35.4% fat) during pregnancy (HFFO). Serum hormones and liver TG, ECS, lipid metabolism, oxidative stress and autophagy markers were assessed in male and female newborn offspring. RESULTS: Maternal HF diet increased liver cannabinoid receptor 1 (CB1) in males and decreased CB2 in females, with no effect on liver TG. Maternal FO supplementation reduced liver CB1 regardless of the offspring sex, but reduced TG liver content only in females. FO reduced the liver content of the endocannabinoid anandamide in males, and the content of 2-arachidonoylglycerol in both sexes. Maternal HF increased lipogenic and decreased lipid oxidation markers, and FO induced the opposite regulation in the liver of offspring. CONCLUSION: Prenatal HF and FO differentially modulate liver ECS in the offspring before obesity and MASLD development. These results suggest that maternal nutrition at critical stages of development can modulate the offspring's ECS, predisposing or preventing the onset of metabolic diseases.

2.
Drug Test Anal ; 16(1): 38-48, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37161689

RESUMO

Dietary supplements (DS) are intended for healthy people to maintain or improve their overall health. Its consumption is widespread in large part of the general population and at all levels of athletes. Nevertheless, DS use can also pose health risks to individuals and, in the case of athletes, may lead to adverse analytical findings (AAFs) due to the possibility of DS contamination or adulteration with doping agents banned by the World Anti-Doping Agency. Although educational initiatives are being performed in Brazil to warn the sports community about inadvertent doping cases, AAFs connected to the DS administration have been increasingly growing. The findings of DS analyzed by the Brazilian Doping Control Laboratory (LBCD), between 2017 and 2022, after Testing Authorities (TAs) analysis requests, showed an alarming number of tainted samples. Diuretics were the most common adulterants found in all supplement types. However, the profile of prohibited substances in manufactured and compounded dietary supplements (MDS and CDS, respectively) were distinct, with stimulants being most prevalent in MDS and anabolic agents in CDS products. Additionally, MDS samples generally presented higher estimated concentrations of banned substances (mg/g) than CDS samples (µg/g). The common practice of DS intake by athletes continues to be of great concern for a doping-free sport, given the high prevalence of prohibited substances detected in the analyzed samples by the LBCD. The current Brazilian scenario reinforces the importance of raising awareness in the sports community of the possible consequences of an unintentional doping case linked to DS use.


Assuntos
Dopagem Esportivo , Esportes , Humanos , Brasil , Diuréticos/análise , Atletas , Suplementos Nutricionais/análise
3.
Front Endocrinol (Lausanne) ; 14: 1087999, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36926037

RESUMO

Introduction: Maternal high-fat (HF) diet during gestation and lactation programs obesity in rat offspring associated with sex-dependent and tissue-specific changes of the endocannabinoid system (ECS). The ECS activation induces food intake and preference for fat as well as lipogenesis. We hypothesized that maternal HF diet would increase the lipid endocannabinoid levels in breast milk programming cannabinoid and dopamine signaling and food preference in rat offspring. Methods: Female Wistar rats were assigned into two experimental groups: control group (C), which received a standard diet (10% fat), or HF group, which received a high-fat diet (29% fat) for 8 weeks before mating and during gestation and lactation. Milk samples were collected to measure endocannabinoids and fatty acids by mass spectrometry. Cannabinoid and dopamine signaling were evaluated in the nucleus accumbens (NAc) of male and female weanling offspring. C and HF offspring received C diet after weaning and food preference was assessed in adolescence. Results: Maternal HF diet reduced the milk content of anandamide (AEA) (p<0.05) and 2-arachidonoylglycerol (2-AG) (p<0.05). In parallel, maternal HF diet increased adiposity in male (p<0.05) and female offspring (p<0.05) at weaning. Maternal HF diet increased cannabinoid and dopamine signaling in the NAc only in male offspring (p<0.05), which was associated with higher preference for fat in adolescence (p<0.05). Conclusion: Contrary to our hypothesis, maternal HF diet reduced AEA and 2-AG in breast milk. We speculate that decreased endocannabinoid exposure during lactation may induce sex-dependent adaptive changes of the cannabinoid-dopamine crosstalk signaling in the developing NAc, contributing to alterations in neurodevelopment and programming of preference for fat in adolescent male offspring.


Assuntos
Canabinoides , Endocanabinoides , Ratos , Animais , Masculino , Feminino , Dieta Hiperlipídica/efeitos adversos , Leite , Dopamina , Preferências Alimentares , Ratos Wistar , Obesidade
4.
Anal Chem ; 93(31): 10990-10998, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34319704

RESUMO

The detection and unambiguous identification of anabolic-androgenic steroid metabolites are essential in clinical, forensic, and antidoping analyses. Recently, sulfate phase II steroid metabolites have received increased attention in steroid metabolism and drug testing. In large part, this is because phase II steroid metabolites are excreted for an extended time, making them a potential long-term chemical marker of choice for tracking steroid misuse in sports. Comprehensive analytical methods, such as liquid chromatography-tandem mass spectrometry (LC-MS/MS), have been used to detect and identify glucuronide and sulfate steroids in human urine with high sensitivity and reliability. However, LC-MS/MS identification strategies can be hindered by the fact that phase II steroid metabolites generate nonselective ion fragments across the different metabolite markers, limiting the confidence in metabolite identifications that rely on exact mass measurement and MS/MS information. Additionally, liquid chromatography-high-resolution mass spectrometry (LC-HRMS) is sometimes insufficient at fully resolving the analyte peaks from the sample matrix (commonly urine) chemical noise, further complicating accurate identification efforts. Therefore, we developed a liquid chromatography-ion mobility-high resolution mass spectrometry (LC-IM-HRMS) method to increase the peak capacity and utilize the IM-derived collision cross section (CCS) values as an additional molecular descriptor for increased selectivity and to improve identifications of intact steroid analyses at low concentrations.


Assuntos
Esteroides , Espectrometria de Massas em Tandem , Cromatografia Líquida , Humanos , Reprodutibilidade dos Testes , Esteroides/urina , Detecção do Abuso de Substâncias
5.
Curr Drug Metab ; 22(5): 372-382, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33593255

RESUMO

BACKGROUND: Dermorphin is a heptapeptide with an analgesic potential higher than morphine that does not present the same risk for the development of tolerance. These pharmacological features make dermorphin a potential doping agent in competitive sports and it is already prohibited for racehorses. For athletes, the development of an efficient strategy to monitor for its abuse necessitates an investigation of the metabolism of dermorphin in humans. METHODS: Here, human liver microsomes and zebrafish were utilized as model systems of human metabolism to evaluate the presence and kinetics of metabolites derived from dermorphin. Five hours after its administration, the presence of dermorphin metabolites could be detected in both models by liquid chromatography coupled to highresolution mass spectrometry. RESULTS: Although the two models showed common results, marked differences were also observed in relation to the formed metabolites. Six putative metabolites, based on their exact masses of m/z 479.1915, m/z 501.1733, m/z 495.1657, m/z 223.1073, m/z 180.1017 and m/z 457.2085, are proposed to represent the metabolic pattern of dermorphin. The major metabolite generated from the administration of dermorphin in both models was YAFG-OH (m/z 457.2085), which is the N-terminal tetrapeptide previously identified from studies on rats. CONCLUSION: Its extensive characterization and commercial availability suggest that it could serve as a primary target analyte for the detection of dermorphin misuse. The metabolomics approach also allowed the assignment of other confirmatory metabolites.


Assuntos
Microssomos Hepáticos/metabolismo , Peptídeos Opioides/metabolismo , Animais , Humanos , Cinética , Peptídeos Opioides/química , Peixe-Zebra
6.
J Mass Spectrom ; 55(10): e4593, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32805775

RESUMO

Dermorphin is a peptide with analgesic actions similar to morphine, but with greater effect and less potential to cause tolerance. The use of dermorphin has been documented in race horses, and its use in humans has already been reported. Considering the potential advantages from the use of dermorphin over morphine, a method to monitor it, and its main metabolite dermorphin (1-4) in humans becomes necessary for doping control. Here, we present two orthogonal methods for this purpose: a high-throughput liquid chromatography coupled to high-resolution mass spectrometry (HRMS) as an initial testing procedure and liquid chromatography-tandem mass spectrometry (MS/MS) in the selected reaction monitoring (SRM) acquisition mode for a confirmation procedure. For urine samples, pretreatment through a mixed-mode weak cation-exchange solid-phase extraction emerged as an effective approach to extract peptides from the biological sample. For the HRMS analysis, a full-MS scan acquisition mode was selected to detect the exact masses of dermorphin and dermorphin (1-4) at m/z 803.37226 and 457.20816, respectively. The SRM method used in the MS/MS confirmation protocol presented high specificity and sensitivity. The selected product ions for dermorphin were 602.2, 202.1 and 574.3 and for dermorphin (1-4) were 207.1, 223.1, and 235.1. Both methods were evaluated for specificity, repeatability, carryover, matrix effects, and recovery. No carryover and matrix effects were detected. The limit of detection for initial testing procedure and the limit of identification for confirmation procedure was 2.5 ng/ml. Also, specificity and robustness were acceptable for the application. Together, the developed methods proved to be efficient for the analysis of dermorphin and metabolite for human doping control purpose.


Assuntos
Analgésicos Opioides/urina , Cromatografia Líquida de Alta Pressão/métodos , Peptídeos Opioides/urina , Espectrometria de Massas em Tandem/métodos , Dopagem Esportivo , Humanos , Limite de Detecção , Extração em Fase Sólida/métodos , Detecção do Abuso de Substâncias/métodos
7.
Zebrafish ; 17(2): 104-111, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32096703

RESUMO

Testolactone is a potent steroid aromatase (CYP19A1) inhibitor, and its main effect is a reduction in estradiol and estrone and an increase in testosterone and androstenedione levels. In this work, we evaluated a zebrafish water tank (ZWT) as a model to investigate testolactone biotransformation and the possibility to increase knowledge regarding the applicability of the ZWT on steroid hormone elimination research, as well as on the impact of steroid hormones on the endogenous metabolism of zebrafish. High-resolution mass spectrometry combined with SIEVE software was used to discriminate the peaks of interest based on significant changes in the relative signal intensity of the m/z values between different ZWT experiments. The metabolites, 4,5-dihydrotestolactone and 1,2,4,5-tetrahydrotestolactone, the same metabolites as those described in humans, were detected in ZWT, both in quite similar proportions. The presence of testolactone in the ZWT caused a rise in testosterone and androstenedione in the water tank, similar to that in human serum. These data suggest that, while the concentration of testolactone was high enough to inhibit the aromatase enzyme, an accumulation of androgens in the water occurred, indicating that the ZWT can be considered a model to investigate the impact of steroids on live organisms.


Assuntos
Inibidores da Aromatase/metabolismo , Testolactona/metabolismo , Peixe-Zebra/metabolismo , Animais , Biotransformação , Hormônios Esteroides Gonadais , Testolactona/análogos & derivados
8.
Med Chem ; 16(4): 487-494, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31309899

RESUMO

BACKGROUND: Approximately, 5-7 million people are infected with T. cruzi in the world, and approximately 10,000 people per year die of complications linked to this disease. METHODS: This work describes the construction of a new family of hidrazonoyl substituted derivatives, structurally designed exploring the molecular hybridization between megazol and nitrofurazone. RESULTS AND DISCUSSION: The compounds were evaluated for their in vitro activity against bloodstream trypomastigotes of Trypanosoma cruzi, etiological agent of Chagas disease, and for their potential toxicity to mammalian cells. CONCLUSION: Among these hydrazonoyl derivatives, we identified the derivative (4) that showed trypanocidal activity (IC50/24 h = 15.0 µM) similar to Bz, the standard drug, and low toxicity to mammalian cells, reaching an SI value of 18.7.


Assuntos
Hidrazonas/síntese química , Hidrazonas/farmacologia , Tripanossomicidas/síntese química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Técnicas de Química Sintética , Hidrazonas/química , Relação Estrutura-Atividade , Tripanossomicidas/química
9.
Anal Bioanal Chem ; 407(14): 4091-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25845527

RESUMO

This work evaluates the application of a thermodynamic model to comprehensive two-dimensional gas chromatography (GC × GC) coupled with time-of-flight mass spectrometry for anabolic agent investigation. Doping control deals with hundreds of drugs that are prohibited in sports. Drug discovery in biological matrices is a challenging task that requires powerful tools when one is faced with the rapidly changing designer drug landscape. In this work, a thermodynamic model developed for the prediction of both primary and secondary retention times in GC × GC has been applied to trimethylsilylated hydroxyl (O-TMS)- and methoxime-trimethylsilylated carbonyl (MO-TMS)-derivatized endogenous steroids. This model was previously demonstrated on a pneumatically modulated GC × GC system, and is applied for the first time to a thermally modulated GC × GC system. Preliminary one-dimensional experiments allowed the calculation of thermodynamic parameters (ΔH, ΔS, and ΔC p ) which were successfully applied for the prediction of the analytes' interactions with the stationary phases of both the first-dimension column and the second-dimension column. The model was able to predict both first-dimension and second-dimension retention times with high accuracy compared with the GC × GC experimental measurements. Maximum differences of -8.22 s in the first dimension and 0.4 s in the second dimension were encountered for the O-TMS derivatives of 11ß-hydroxyandrosterone and 11-ketoetiocholanolone, respectively. For the MO-TMS derivatives, the largest discrepancies were from testosterone (9.65 ) for the first-dimension retention times and 11-keto-etiocholanolone (0.4 s) for the second-dimension retention times.


Assuntos
Cromatografia Gasosa/métodos , Espectrometria de Massas/métodos , Esteroides/química , Termodinâmica
10.
J Chromatogr A ; 1298: 76-85, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23746644

RESUMO

The detection of 11 sympathomimetic alkylamines in urine was presented with a focus on human doping control is proposed using liquid chromatography tandem mass spectrometry (LC-QqQ) and high resolution mass spectrometry (LC-HRMS) as a screening tool after a dilute-and-shoot (DS) approach. For the LC-HRMS analyses, several compounds exhibited better limits of detection (L.O.D.) than the LC-QqQ. However, due to their small differences in structure, co-elution among the alkylamines was observed. Therefore, the chemical conversion of the alkylamines into an appropriate derivative for the confirmation analyses using gas chromatography-mass spectrometry (GC-MS) was evaluated. Five derivatization approaches were evaluated in an attempt to increase the analytical response and the confidence of the identification. The choice of the appropriated derivative for each alkylamine makes their spectra more easily interpretable, fulfills the WADA's rather strict identification criteria and enables the unequivocal identification of alkylamines in urine.


Assuntos
Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Simpatomiméticos/análise , Espectrometria de Massas em Tandem/métodos , Humanos
11.
Rapid Commun Mass Spectrom ; 24(22): 3297-302, 2010 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-20973004

RESUMO

Trimethylsilylation of anabolic agents and their metabolites is frequently achieved by using the derivatization mixture N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA)/NH(4)I/2-mercaptoethanol. Nevertheless, artifacts were formed when this mixture was employed in the monitoring of exemestane and its main metabolite 17ß-hydroxyexemestane prior to GC-MS analysis. These artifacts were identified as the N-methyltrifluoroacetamide (MTFA) and trimethylsiloxyethylmercapto products of the respective trimethylsilyl (TMS) derivatives. Furthermore, artifact formation was evaluated taking the structure (1,4-diene-3-keto-6-exomethylene) of the compounds into account. Although these artifacts are relevant for investigations regarding the derivatization process and may be of interest in many fields, they are detrimental to cope with the requirements of the World Anti-Doping Agency (WADA) in terms of the limits of detection (LODs) required. To overcome this issue, a method using an alternative derivatization was proposed: formation of methyloxime-TMS derivatives through double derivatization using O-methylhydroxylamine/pyridine and MSTFA/TMS imidazole after enzymatic hydrolysis and liquid-liquid extraction. Samples from an excretion study after administration of exemestane to healthy volunteers were analyzed by the proposed method and detection of both exemestane and its main metabolite was possible. This method showed excellent results for both analytes meeting the LODs required for antiestrogenic agents (50 ng/mL) established by WADA. The method was validated for the main metabolite, it was robust and cost-effective for qualitative and quantitative purposes, with LOD and LOQ of 10 ng/mL and 25 ng/mL, respectively.


Assuntos
Androstadienos/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Acetamidas , Adulto , Androstadienos/química , Androstadienos/farmacocinética , Artefatos , Dopagem Esportivo , Fluoracetatos , Humanos , Masculino , Oximas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ácido Trifluoracético/química , Compostos de Trimetilsilil/química
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