Human in vivo metabolism study of LGD-4033 Fragkaki, Argyro G; Sakellariou, Panagiotis; Kiousi, Polyxeni ...
Drug testing and analysis
10, Številka:
11-12
Journal Article
Recenzirano
Selective androgen receptor modulators (SARMs) are an emerging class of therapeutics targeted to cachexia, sarcopenia, and hypogonadism treatment. LGD-4033 is a SARM which has been included on the ...Prohibited List annually released by the World Anti-Doping Agency (WADA). The aim of the present work was the investigation of the metabolism of LGD-4033 in a human excretion study after administration of an LGD-4033 supplement, the determination of the metabolites' excretion profiles with special interest in the determination of its long-term metabolites, and the comparison of the excretion time of the phase I and phase II metabolites. The results were also compared to those derived from previous LGD-4033 studies concerning both in vitro and in vivo experiments. Supplement containing LGD-4033 was administered to one human male volunteer and urine samples were collected up to almost 21 days. Analysis of the hydrolyzed (with β-glucuronidase) as well as of the non-hydrolyzed samples was performed using liquid chromatography-high resolution mass spectrometry (LC-HRMS) in negative ionization mode and revealed that, in both cases, the two isomers of the dihydroxylated metabolite (M5) were preferred target metabolites. The gluco-conjugated parent LGD-4033 and its gluco-conjugated metabolites M1 and M2 can be also considered as useful target analytes in non-hydrolyzed samples. The study also presents two trihydroxylated metabolites (M6) identified for the first time in human urine; one of them was recently reported in an LGD-4033 metabolism study in horse urine and plasma.
Intact phase II steroid metabolites have poor product ion mass spectra under collision-induced dissociation (CID) conditions. Therefore, we present herein the liquid chromatography-electrospray ...ionization-tandem mass spectrometry (LC-ESI-MS/(MS)) behavior of intact phase II metabolites of oxosteroids after derivatization. Based on the fact that Girard's reagent T (GRT), as derivatization reagent, was both convenient and efficient in terms of the enhancement in the ionization efficiency and the production of diagnostic product ions related to the steroid moiety, the latter was preferably selected between methoxamine and hydroxylamine upon the model compounds of androsterone glucuronide and androsterone sulfate. Sixteen different glucuronides and 29 sulfate conjugated metabolites of anabolic androgenic steroids (AASs), available either as pure reference materials or synthesized/extracted from administration studies, were derivatized with GRT, and their product ion spectra are presented. Product ion spectra include in all cases high number of product ions that in some cases are characteristic for certain structures of the steroid backbone. More specifically, preliminary results have shown major differences in fragmentation pattern for 17α/17β-isomers of the sulfate conjugates, but limited differentiation for 17α/17β-isomers of glucuronide conjugates and for 3α/3β- and 5α/5β-stereoisomers of both sulfate and glucuronide conjugates. Further to the suggestion of the current work, application on mesterolone administration studies confirmed-according to the World Anti-Doping Agency (WADA) TD2015IDCR-the presence of seven intact phase II metabolites, one glucuronide and six sulfates with use of LC-ESI-MS/(MS).
Anabolic androgenic steroids are widely abused substances in sports doping. Their detection present limitations regarding the use of soft ion sources such as electrospray or atmospheric pressure ...chemical ionization by liquid chromatography–tandem mass spectrometry. In the current study, a novel derivatization method was developed for the ionization enhancement of selected anabolic androgenic steroids. The proposed method aims at the introduction of an easily ionizable moiety into the steroid molecule by converting the hydroxyl groups into imidazole carbamates using 1,1′‐carbonyldiimidazole as derivatization reagent. The proposed method was applied to water and urine samples spiked with exogenous anabolic androgenic steroids in various concentration levels. Steroid imidazole carbamate derivatives have shown intensive M+H+ signals under electrospray ionization and common fragmentation patterns in tandem mass spectrometry mode with M‐CO2+H+ and M‐ΙmCO2+H+ as major ions with low collision energy. The obtained results showed that the majority of steroids were detectable at concentrations equal or lower to their minimum required performance level according to the World Anti‐Doping Agency technical document. The proposed method is sensitive with a preparation procedure that could be easily applied to the analysis of doping control samples.
Novel metabolites of the anabolic androgenic steroid 17α‐methyltestosterone have been detected in HepG2 cell in vitro metabolic model and in human urine. Their detection was accomplished through ...targeted gas chromatography–(tandem) mass spectrometry analysis that has been based on microscale synthesized standards. The related synthesis and the gas chromatography–(tandem) mass spectrometry characterization of the analytical standards are described. All newly presented metabolites have a fully reduced steroid A‐ring with either an 17,17‐dimethyl‐18‐nor‐Δ13 structure or they have been further oxidized at position 16 of the steroid backbone. Metabolites with 17,17‐dimethyl‐18‐nor‐Δ13 structure may be considered as side products of phase II metabolic sulfation of the 17β‐hydroxy group of methyltestosterone or its reduced tetrahydro‐methyltestosterone metabolites 17α‐methyl‐5β‐androstane‐3α,17β‐diol and 17α‐methyl‐5α‐androstane‐3α,17β‐diol that produce the known epimeric 17β‐methyl‐5β‐androstane‐3α,17α‐diol and 17β‐methyl‐5α‐androstane‐3α,17α‐diol metabolites. The prospective of these new metabolites to increase detection time windows and improve identification was investigated by applying the World Anti‐doping Agency TD2021IDCR criteria. The new metabolites, presented herein, complement the current knowledge on the 17α‐methyltestosterone metabolism and in some cases can be used as additional long‐term markers in the frame of sport doping drug testing.
Novel fully A‐ring‐reduced metabolites of methyltestosterone were predicted and synthesized on a microscale. Their GC‐MS/(MS) behavior was studied to develop a targeted detection method. Targeted analysis of methyltestosterone HepG2 cell incubation supernatants and post‐administration urine samples confirmed the presence of these novel methyltestosterone metabolites in both matrices. Evaluation of their human urine post‐administration excretion profiles revealed that some of them could be used as additional long‐term metabolites for the monitoring of methyltestosterone in the frame of doping control.
Although the use of nutritional supplements by adult athletes has been extensively studied, information on supplements consumption by adolescent athletes is still limited. The present study reports ...on the use of nutritional supplements contaminated with banned doping substances among 170 recreational adolescent athletes from eleven, randomly selected, gym centres, in Athens, Greece. Nutritional supplements consumption was reported by almost 60% of the study population, with proteins/amino acids and vitamins being the most popular. Nine per cent of the users were found to consume nutritional supplements contaminated with anabolic steroids, prohormones, selective androgen receptor modulators (SARMs) and aromatase inhibitors, all pharmacological substances with endocrine modulating properties not stated on the label. None of these individuals had previously consulted a physician or a nutritionist. A representative sample (ca 15%) of the protein/aminoacids and creatine preparations used by the study population were also tested and found free from doping substances. The majority (63%) of adolescents purchased products from the internet. In conclusion, exercising adolescents can have easy access to contaminated nutritional supplements and “black market” products, which could constitute a risk for public health. Low level of awareness and low involvement of medical care professionals among recreational adolescent athletes is also observed.
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•Almost 60% of recreational adolescent athletes in Greece use nutritional supplements.•Nine per cent of the users were found to consume nutritional supplements contaminated with doping substances.•Contaminations were pharmacological substances with endocrine modulating properties not stated on the label.•Protein/aminoacids and creatine preparations tested were found free from doping substances.
The modern way of life involves high stress levels, poor eating habits, lack of exercise, obesity and other detrimental health factors. Nutritional supplements (NS) are complexes of nutrients with ...variant activity that may infer reversal to nutrient depletion. They tend to be popular amongst social categories associated with the healthy life style, such as the elite and amateur athletes, military people and the general population.
An overview of the state of play with regard to nutritional supplements - natural and synthetic-, is important both from toxicological and commercial point of view.
From a thorough literature review on nutritional supplements, several patents of application have been identified and herewith reviewed which recommend natural vegetable extracts as food supplements for prophylaxis, therapy, protection of immune system, diabetes, oxidative stress, cancer, chronic inflammations and other health conditions. Besides, nutritional supplements of pharmacological validity and high popularity are discussed relative to their contents and group of use.
Cases of adulteration or unintentional contamination of commercial products with abusing substances (doping substances, narcotics etc.) or toxic compounds (heavy metals, plant toxics) have shed light to the problem of causing recalls of some products by the FDA.
From the safety/ quality point of view, NS lack of harmonisation and sovereign laws/ institutional controls on the market and their wide commercialization may possibly lead to risks to public health.
In the present study, an attempt was made to compare three stress models and their effects on the hypothalamic–pituitary–adrenal (HPA) axis, the thymus, the thyroid hormones and the glucose levels. ...The three different stress models were the chronic mild stress (CMS), the 14-day and the 1-day cold swim stress model. The CMS procedure caused a decrease in thymus weight and rendered no changes on glucose, the adrenocorticotropin hormone (ACTH) or the adrenals. Administration of imipramine (IMI) after the third week of CMS did not reverse the decrease in thymus weight. The 14-day cold swim stress doubled ACTH levels and the adrenal weight and reduced thymus weight, while total thyroxine (tT4), total triiodothyronine (tT3) and glucose levels were unaffected. IMI treatment restored the weights of the adrenal and thymus glands. One-day cold swim stress did not induce any statistically significant effect on the tested physiological parameters. The above findings indicate a distinct effect of the 14-day cold swim stress on HPA axis. Relative to CMS or the 14-day cold swim stress, no effect was induced by the 1-day cold swim stress. The IMI restoring effect, especially in the case of the 14-day cold swim stress, also suggests an association of antidepressant effect with the duration of drug treatment.
•Patients with metabolic syndrome were supplemented with tomato-juice.•Inflammation status, endothelial dysfunction and insulin resistance improved.•A pronounced decrease in LDL was recorded, along ...with a slight increase in HDL.
Lycopene, a carotenoid, is known for its antioxidant properties. Little is known, though, about the relationship of dietary tomato-juice intake and risks factors, like inflammation, insulin resistance and hyperlipidemia, implicated in metabolic syndrome. In the present study, we examined whether supplementation with tomato-juice has any implication on the risk status of patients with metabolic syndrome. A comparative study was conducted in 27 individuals diagnosed with metabolic syndrome. Fifteen of them were instructed to use commercially available tomato-juice as refreshment 4 times a week over a period of two months and twelve individuals served as the control group. Several parameters reflective of the metabolic syndrome were monitored both in the group supplemented with tomato juice and in the control group (ADMA for entdothelial function, TNF-α and IL-6 for inflammation, FIRI for insulin resistance). There was a significant improvement in the inflammation status and the endothelial dysfunction of the tomato-juice supplemented patients. At the same time, insulin resistance improved and a pronounced decrease in LDL was recorded, along with a slight increase in HDL. The results of the present study suggest an alleviating effect of tomato-juice with regard to risk factors associated with metabolic syndrome.
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