Five Novel Polymorphs of Cardarine/GW501516 and Their Characterization by X-ray Diffraction, Computational Methods, Thermal Analysis and a Pharmaceutical Perspective

GW501516, also known by the name of cardarine, is a synthetic peroxisome-proliferator-activated receptor delta (PPR-δ) agonist agent developed for applications in the treatment of metabolic disorders and cardiovascular diseases. A broad polymorph screening in various solvents and mixtures was completed in order to explore its capabilities to grow polymorphs. The crystal structures of four polymorphs were elucidated using single-crystal X-ray diffraction, while one structure was solved via a powder X-ray diffraction method. The solid state features (nature of intermolecular interactions) were investigated by computational methods. The polymorphs were further investigated by thermal DSC analysis and X-ray diffraction on powders. From a pharmaceutical perspective, the stability and solubility of the polymorphs were analyzed as well.

Probing the hair detectability of prohibited substances in sports: an in vivo-in silico-clinical approach and analytical implications compared with plasma, urine, and faeces

Hair analysis is a crucial method in forensic toxicology with potential applications in revealing doping histories in sports. Despite its widespread use, knowledge about detectable substances in hair is limited. This study systematically assessed the detectability of prohibited substances in sports using a multifaceted approach. Initially, an animal model received a subset of 17 model drugs to compare dose dependencies and detection windows across different matrices. Subsequently, hair incorporation data from the animal experiment were extrapolated to all substances on the World Anti-Doping Agency's List through in-silico prediction. The detectability of substances in hair was further validated in a proof-of-concept human study involving the consumption of diuretics and masking agents. Semi-quantitative analysis of substances in specimens was performed using ultra-performance liquid chromatography-tandem mass spectrometry. Results showed plasma had optimal dose dependencies with limited detection windows, while urine, faeces, and hair exhibited a reasonable relationship with the administered dose. Notably, hair displayed the highest detection probability (14 out of 17) for compounds, including anabolic agents, hormones, and diuretics, with beta-2 agonists undetected. Diuretics such as furosemide, canrenone, and hydrochlorothiazide showed the highest hair incorporation. Authentic human hair confirmed diuretic detectability, and their use duration was determined via segmental analysis. Noteworthy is the first-time reporting of canrenone in human hair. Anabolic agents were expected in hair, whereas undetectable compounds, such as peptide hormones and beta-2 agonists, were likely due to large molecular mass or high polarity. This study enhances understanding of hair analysis in doping investigations, providing insights into substance detectability.

Inhibitory Effect of PPARδ Agonist GW501516 on Proliferation of Hypoxia-induced Pulmonary Arterial Smooth Muscle Cells by Regulating the mTOR Pathway

OBJECTIVE

This study aimed to investigate the effects of the peroxisome proliferator-activated receptor δ (PPARδ) agonist GW501516 on the proliferation of pulmonary artery smooth muscle cells (PASMCs) induced by hypoxia, in order to search for new drugs for the treatment and prevention of pulmonary vascular remodeling.

METHODS

PASMCs were incubated with different concentrations of GW501516 (10, 30, 100 nmol/L) under the hypoxic condition. The proliferation was determined by a CCK-8 assay. The cell cycle progression was analyzed by flow cytometry. The expression of PPARδ, S phase kinase-associated protein 2 (Skp2), and cell cycle-dependent kinase inhibitor p27 was detected by Western blotting. Then PASMCs were treated with 100 nmol/ L GW501516, 100 nmol/L mammalian target of rapamycin (mTOR) inhibitor rapamycin and/or 2 µmol/L mTOR activator MHY1485 to explore the molecular mechanisms by which GW501516 reduces the proliferation of PASMCs.

RESULTS

The presented data demonstrated that hypoxia reduced the expression of PPARδ in an oxygen concentration- and time-dependent manner, and GW501516 decreased the proliferation of PASMCs induced by hypoxia by blocking the progression through the G0/G1 to S phase of the cell cycle. In accordance with these findings, GW501516 downregulated Skp2 and upregulated p27 in hypoxia-exposed PASMCs. Further experiments showed that rapamycin had similar effects as GW501516 in inhibiting cell proliferation, arresting the cell cycle, regulating the expression of Skp2 and p27, and inactivating mTOR in hypoxia-exposed PASMCs. Moreover, MHY1485 reversed all the beneficial effects of GW501516 on hypoxia-stimulated PASMCs.

CONCLUSION

GW501516 inhibited the proliferation of PASMCs induced by hypoxia through blocking the mTOR/Skp2/p27 signaling pathway.

Cannabinoids and PPAR Ligands: The Future in Treatment of Polycystic Ovary Syndrome Women with Obesity and Reduced Fertility

Cannabinoids (CBs) are used to treat chronic pain, chemotherapy-induced nausea and vomiting, and multiple sclerosis spasticity. Recently, the medicinal use of CBs has attracted increasing interest as a new therapeutic in many diseases. Data indicate a correlation between CBs and PPARs via diverse mechanisms. Both the endocannabinoid system (ECS) and peroxisome proliferator-activated receptors (PPARs) may play a significant role in PCOS and PCOS related disorders, especially in disturbances of glucose-lipid metabolism as well as in obesity and fertility. Taking into consideration the ubiquity of PCOS in the human population, it seems indispensable to search for new potential therapeutic targets for this condition. The aim of this review is to examine the relationship between metabolic disturbances and obesity in PCOS pathology. We discuss current and future therapeutic interventions for PCOS and related disorders, with emphasis on the metabolic pathways related to PCOS pathophysiology. The link between the ECS and PPARs is a promising new target for PCOS, and we examine this relationship in depth.

Long-term monitoring of IOX4 in horse hair and its longitudinal distribution with segmental analysis using liquid chromatography/electrospray ionization Q Exactive high-resolution mass spectrometry for the purpose of doping control

IOX4, a hypoxia-inducible factor stabilizer, is classified as a banned substance for horses in both horse racing and equestrian sports. We recently reported the pharmacokinetic profiles of IOX4 in horse plasma and urine and also identified potential monitoring targets for the doping control purpose. In this study, a long-term longitudinal analysis of IOX4 in horse hair after a nasoesophageal administration of IOX4 (500 mg/day for three days) to three thoroughbred mares is presented for the first time for controlling the abuse/misuse of IOX4. Six bunches of mane hair were collected at 0 (pre), 1, 2, 3, and 6 month(s) post-administration. Our results showed that the presence of IOX4 was identified in all post-administration horse hair samples but no metabolite could be detected. The detection window for IOX4 could achieve up to 6-month post-administration (last sampling point) by monitoring IOX4 in hair. In order to evaluate the longitudinal distribution of IOX4 over six months, a validated quantification method of IOX4 in hair was developed for the analysis of the post-administration samples. Segmental analysis of 2-cm cut hair across the entire length of post-administration hair showed that IOX4 could be quantified up to the level of 1.84 pg/mg. In addition, it was found that the movement of the incorporated IOX4 band in the hair shaft over six months varied among the three horses due to individual variation and a significant diffusion of IOX4 band up to 10 cm width was also observed in the 6-month post-administration hair samples.

Liquid chromatography-tandem mass spectrometry and confirmation by liquid chromatography-high-resolution mass spectrometry hair tests to evidence use of tizanidine by racing cyclists

Tizanidine, an imidazoline derivative close to clonidine, is a central alpha-2 adrenergic receptor agonist. Therapeutically, the drug is used as a muscle relaxant under the trade names Sirdalud™ or Zanaflex™. The drug is not prohibited by the World Anti-Doping Agency but, for therapeutic purposes, can only be obtained via a nominative temporary use authorization. The French public health police requested the laboratory to test for tizanidine in head hair specimens collected from international racing cyclists. Using Liquid chromatography-tandem mass spectrometry (LC/MS-MS) and confirmation by liquid chromatography-high-resolution mass spectrometry (LC/HRMS), after pH 9.5 borate buffer overnight incubation of 20 mg and subsequent solvents extraction, tizanidine was identified in the hair of three athletes at 1.1, 3.7, and 11.1 pg/mg. This is the first evidence that tizanidine is incorporated in human hair. However, it was not possible to interpret the data in terms of doses and frequency of use due to a lack of controlled study.

Development and validation of SARMs and metabolic modulators screening in hair using UHPLC-MS/MS: Application to a doping case and first identification of S23 in authentic human hair

Selective Androgen Receptors Modulators (SARMs) are a new class of doping drugs that emerged in sport since 2008. Easy access on the Internet also leads to their misuse by amateurs. It seems important for a laboratory of toxicology to develop a targeted screening of SARMs, given their health risks. A method has been developed and validated for the analysis in hair of 9 SARMs (AC262536, ACP-105, andarine, LGD-4033, MK-0773, MK 677, ostarine, RAD 410 and S23) and 2 other metabolic modulators (GW501516, SR9009), using liquid chromatography coupled to tandem mass spectrometry. After addition of bicalutamide-D₄ used as internal standard and incubation in phosphate buffer pH = 9.5, 20 mg of hair samples were extracted with liquid/liquid extraction. Linearity was verified for all compounds between 0.5 and 50 and 2000 pg/mg. LOD and LOQ were determined between 0.1-20 and 0.5-50 pg/mg respectively, according to the various analytes. Intra- and inter-day precision (CV < 20%), matrix effects and recovery were evaluated for all compounds with CVs < 20%. The application and the interest of SARMs screening was demonstrated in a doping case. Three SARMs were detected namely andarine (120-1644 pg/mg), ostarine (1-9 pg/mg) and S23 (0.6-16 pg/mg) in 6x1 cm segments of the subject.

Peroxisome Proliferator-Activated Receptor Delta Agonist (PPAR- δ) and Selective Androgen Receptor Modulator (SARM) Abuse: Clinical, Analytical and Biological Data in a Case Involving a Poisonous Combination of GW1516 (Cardarine) and MK2866 (Ostarine)

A 43-year-old male, sport coach, presented him-self at the Emergency unit of a local hospital for epigastric pain, myalgia pain and severe headache. He claimed having used for some days a combination of GW1516 (cardarine), a peroxisome proliferator-activated receptor delta agonist (PPAR- δ) and MK2866 (ostarine), a selective androgen receptor modulator (SARM) to gain skeletal muscles. Cytolysis with marked increase of alanine aminotransferase or ALT (up to 922 UI/L) and aspartate aminotransferase or AST (up to 2558 UI/L) and massive rhabdomyolysis with elevated creatine phosphokinase or CPK (up to 86435 UI/L) were the main unusual biochemistry parameters. Using a specific liquid chromatography coupled to tandem mass spectrometry method, cardarine and ostarine tested positive in blood at 403 and 1 ng/mL, respectively. In urine, due to extensive metabolism, the parent GW1516 was not identified, while ostarine was at 88 ng/mL. Finally, both drugs were identified in hair (2 cm in length, brown in colour), at 146 and 1105 pg/mg for cardarine and ostarine, respectively. This clearly demonstrates repetitive abuse over the last 2 months. Asthenia was persistent for 2 weeks and 6 weeks after the admission, the subject fully recovered.

Detection of Methylphenidate in Equine Hair Using Liquid Chromatography-High-Resolution Mass Spectrometry

Methylphenidate is a powerful central nervous system stimulant with a high potential for abuse in horse racing. The detection of methylphenidate use is of interest to horse racing authorities for both prior to and during competition. The use of hair as an alternative sampling matrix for equine anti-doping has increased as the number of detectable compounds has expanded. Our laboratory developed a liquid chromatography–high-resolution mass spectrometry method to detect the presence of methylphenidate in submitted samples. Briefly, hair was decontaminated, cut, and pulverized prior to liquid–liquid extraction in basic conditions before introduction to the LC-MS system. Instrumental analysis was conducted using a Thermo Q Exactive mass spectrometer using parallel reaction monitoring using a stepped collision energy to obtain sufficient product ions for qualitative identification. The method was validated and limits of quantitation, linearity, matrix effects, recovery, accuracy, and precision were determined. The method has been applied to confirm the presence of methylphenidate in official samples submitted by racing authorities.

Targeting Energy Expenditure-Drugs for Obesity Treatment

Obesity and overweight are associated with lethal diseases. In this context, obese and overweight individuals infected by COVID-19 are at greater risk of dying. Obesity is treated by three main pharmaceutical approaches, namely suppressing appetite, reducing energy intake by impairing absorption, and increasing energy expenditure. Most compounds used for the latter were first envisaged for other medical uses. However, several candidates are now being developed explicitly for targeting obesity by increasing energy expenditure. This review analyzes the compounds that show anti-obesity activity exerted through the energy expenditure pathway. They are classified on the basis of their development status: FDA-approved, Withdrawn, Clinical Trials, and Under Development. The chemical nature, target, mechanisms of action, and description of the current stage of development are described for each one.

Detection and longitudinal distribution of GW1516 and its metabolites in equine hair for doping control using liquid chromatography/high-resolution mass spectrometry

RATIONALE

GW1516 is a peroxisome proliferator-activated receptor-δ (PPAR-δ) agonist that is banned in horseracing and equestrian sports. Long-term detection and longitudinal distribution of GW1516 in the mane of a horse are reported for the first time and this hair analysis could prolong the detection window of GW1516 for doping control.

METHODS

Mane hairs were divided into three segments (0-7, 7-15, and >15 cm from the cut end) and completely pulverized and homogenized for analysis. The pulverized hair samples were extracted with methanol followed by further purification and the extracts were analyzed by liquid chromatography/electrospray ionization high-resolution mass spectrometry (LC/ESI-HRMS) using a Q-Exactive instrument. This method was successfully validated and applied to post-administration samples to confirm the presence of GW1516 and its metabolites and estimate the uptake amounts of GW1516.

RESULTS

After administration of 150 mg of GW1516 to a thoroughbred mare, GW1516 was detected in one of two segments of all mane hairs, and four metabolites, namely GW1516 sulfoxide, GW1516 sulfone, 5-(hydroxymethyl)-4-methyl-2-(4-trifluoromethylphenyl)thiazole (HMTT), and 4-methyl-2-[4-(trifluoromethyl)phenyl]-1,3-thiazole-5-carboxylic acid (MTTC), were also identified. The longitudinal distribution analysis results showed that the maximum uptake of GW1516 into hair (approximately 0.05 pg/mg) was observed at around 13 weeks post-administration and GW1516 could be detected and confirmed up to 6 months post-administration.

CONCLUSIONS

The parent drug GW1516 was identified as the most appropriate monitoring target in equine hair for controlling its misuse in horses. The use of hair analysis could extend the detection time of GW1516 to at least 6 months after the administration of 150 mg of GW1516 to a thoroughbred mare.

Comprehensive characterization of the peroxisome proliferator activated receptor-δ agonist GW501516 for horse doping control analysis

According to international sport institutions, the use of peroxisome proliferator activated receptor (PPAR)-δ agonists is forbidden at any time in athlete career due to their capabilities to increase physical and endurance performances. The (PPAR)-δ agonist GW501516 is prohibited for sale but is easily available on internet and can be used by cheaters. In the context of doping control, urine is the preferred matrix because of the non-invasive nature of sampling and providing broader exposure detection times to forbidden molecules but often not detected under its native form due to the organism's metabolism. Even if urinary metabolism of G501516 has been extensively studied in human subjects, knowledge on GW501516 metabolism in horses remains limited. To fight against doping practices in horses' races, GW501516 metabolism has to be studied in horse urine to identify and characterize the most relevant target metabolites to ensure an efficient doping control. In this article, in vitro and in vivo experiments have been conducted using horse S9 liver microsome fractions and horse oral administration route, respectively. These investigations determined that the detection of GW501516 must be performed in urine on its metabolites because the parent molecule was extremely metabolized. To maximize analytical method sensitivity, the extraction conditions have been optimized. In accordance with these results, a qualitative analytical method was validated to detect the abuse of GW501516 based on its most relevant metabolites in urine. This work enabled the Laboratoire des Courses Hippiques (LCH) to highlight two cases of illicit administration of this forbidden molecule in post-race samples.

Annual banned-substance review: Analytical approaches in human sports drug testing 2019/2020

Analytical chemistry-based research in sports drug testing has been a dynamic endeavor for several decades, with technology-driven innovations continuously contributing to significant improvements in various regards including analytical sensitivity, comprehensiveness of target analytes, differentiation of natural/endogenous substances from structurally identical but synthetically derived compounds, assessment of alternative matrices for doping control purposes, and so forth. The resulting breadth of tools being investigated and developed by anti-doping researchers has allowed to substantially improve anti-doping programs and data interpretation in general. Additionally, these outcomes have been an extremely valuable pledge for routine doping controls during the unprecedented global health crisis that severely affected established sports drug testing strategies. In this edition of the annual banned-substance review, literature on recent developments in anti-doping published between October 2019 and September 2020 is summarized and discussed, particularly focusing on human doping controls and potential applications of new testing strategies to substances and methods of doping specified the World Anti-Doping Agency's 2020 Prohibited List.