Alleviation of neuropathic pain by cannabinoids is limited by their central nervous system (CNS) side effects. Indole and indene compounds were engineered for high hCB1R affinity, peripheral selectivity, metabolic stability, and in vivo efficacy. An epithelial cell line assay identified candidates with <1% blood-brain barrier penetration for testing in a rat neuropathy induced by unilateral sciatic nerve entrapment (SNE). The SNE-induced mechanical allodynia was reversibly suppressed, partially or completely, after intraperitoneal or oral administration of several indenes. At doses that relieve neuropathy symptoms, the indenes completely lacked, while the brain-permeant CB1R agonist HU-210 (1) exhibited strong CNS side effects, in catalepsy, hypothermia, and motor incoordination assays. Pharmacokinetic findings of ∼0.001 cerebrospinal fluid:plasma ratio further supported limited CNS penetration. Pretreatment with selective CB1R or CB2R blockers suggested mainly CB1R contribution to an indene's antiallodynic effects. Therefore, this class of CB1R agonists holds promise as a viable treatment for neuropathic pain.

/pdf/peripherally-selective-cannabinoid-1-receptor-cb1r-agonists-fi2okgjaei.pdf

Peripherally Selective Cannabinoid 1 Receptor (CB1R) Agonists for the Treatment of Neuropathic Pain

With laboratories seeking to expand analytical capabilities and create multi-class, multi-analyte methods, there has been a shift toward generic sample clean-up techniques such as “dilute-and-shoot” Advantages of this methodology include its simplicity, minimal analyte losses, high sample throughput and number of analyte classes included The evolution of dilute-and-shoot has permitted its use across a variety of matrices including food and biological and in various scientific fields such as food, forensics and environmental The versatility of the technique permits the expansion of current fields of research without the usual laborious method development There can be issues with matrix effects and robust quantitation as analyte number increases This review provides an overview of the technique combined with liquid chromatography mass spectrometry, highlighting its power in facilitating multi-class analysis Coupled with increases in instrument performance there is potential to employ this methodology in expanding analytical capabilities in many areas of life science research

Redefining dilute and shoot: The evolution of the technique and its application in the analysis of foods and biological matrices by liquid chromatography mass spectrometry

A narrative review with an overall aim of indicating the current state of knowledge and the relevance concerning food and supplement contamination and/or adulteration with doping agents and the respective implications for sports drug testing is presented. The identification of a doping agent (or its metabolite) in sports drug testing samples constitutes a violation of the anti-doping rules defined by the World Anti-Doping Agency. Reasons for such Adverse Analytical Findings (AAFs) include the intentional misuse of performance-enhancing/banned drugs; however, also the scenario of inadvertent administrations of doping agents was proven in the past, caused by, amongst others, the ingestion of contaminated dietary supplements, drugs, or food. Even though controversial positions concerning the effectiveness of dietary supplements in healthy subjects exist, they are frequently used by athletes, anticipating positive effects on health, recovery, and performance. However, most supplement users are unaware of the fact that the administration of such products can be associated with unforeseeable health risks and AAFs in sports. In particular anabolic androgenic steroids (AAS) and stimulants have been frequently found as undeclared ingredients of dietary supplements, either as a result of cross-contaminations due to substandard manufacturing practices and missing quality controls or an intentional admixture to increase the effectiveness of the preparations. Cross-contaminations were also found to affect therapeutic drug preparations. While the sensitivity of assays employed to test pharmaceuticals for impurities is in accordance with good manufacturing practice guidelines allowing to exclude any physiological effects, minute trace amounts of contaminating compounds can still result in positive doping tests. In addition, food was found to be a potential source of unintentional doping, the most prominent example being meat tainted with the anabolic agent clenbuterol. The athletes’ compliance with anti-doping rules is frequently tested by routine doping controls. Different measures including offers of topical information and education of the athletes as well as the maintenance of databases summarizing low- or high-risk supplements are important cornerstones in preventing unintentional anti-doping rule violations. Further, the collection of additional analytical data has been shown to allow for supporting result management processes.

https://www.mdpi.com/2304-8158/9/8/1012/pdf

Dietary Supplement and Food Contaminations and Their Implications for Doping Controls.

Background: Higenamine is a stimulant with cardiovascular properties recently prohibited in sport by the World Anti-Doping Agency (WADA) Higenamine is also a natural constituent of several traditi

The stimulant higenamine in weight loss and sports supplements

Technical innovations are continuously offering new options to research and routine applications in various arenas of analytical chemistry. In combination with a concomitantly increasing knowledge in physiology and pharmacology and a steadily growing supply of new drug candidates and potential therapeutic approaches, sports drug testing laboratories have been urged to develop and refine numerous test methods and strategies in order to provide best-possible levels of information to testing authorities in support of decision-making processes in anti-doping.

Analytical Approaches in Human Sports Drug Testing: Recent Advances, Challenges, and Solutions.

Higenamine (Norcoclaurine) is a very popular substance in Chinese medicine and is present in many plants. The substance may be also found in supplements or nutrients, consumption of which may result in violation of anti-doping rules. Higenamine is prohibited in sport at all times and included in Class S3 (β-2-agonists) of the World Anti-Doping Agency (WADA) 2017 Prohibited List. The presence of higenamine in urine samples at concentrations greater than or equal to 10 ng/mL constitutes an adverse analytical finding (AAF). This work presents a new metabolite of higenamine in urine sample which was identified by means of ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Samples were prepared according to 2 protocols - a Dilute and Shoot (DaS) approach and a method involving acid hydrolysis and double liquid-liquid extraction (LLE). To meet the requirements typical for a confirmatory analysis, the screening procedure was further developed. In samples prepared by the DaS method, 2 peaks were observed; the earlier one was specific for higenamine and the later one unknown. MS scan analysis showed mass about 80 Da higher than that of higenamine. In turn, in samples prepared in accordance with the protocol involving hydrolysis, an increase in the area under peak for higenamine was observed, while the second peak was absent. It seems that the described strategy of detection of higenamine in urine avoids false negative results.

Analysis for higenamine in urine by means of ultra-high-performance liquid chromatography–tandem mass spectrometry: Interpretation of results

The use of a valid and straightforward method for the identification of higenamine in dietary supplements in view of anti-doping rule violation cases

2-(Ethylthio) benzimidazole is an active ingredient of Antihot, a dietary supplement sold in Ukraine. The substance, available also under names of Bemitil, Metaprot, and Bemaktor, was developed in the USSR in 1970s, and after tests on Soviet cosmonauts and soldiers, several studies on its influence on athletes' performances were conducted. The research showed that bemitil is a synthetic adaptogen which is capable to significantly increase physical performance and reduce the time of regeneration. Moreover, according to supplement's distributor, the substance improves both physical performance and resistance to stress. Taking into account these properties, it appears plausible that the World Anti-Doping Agency (WADA) decided to include bemitil in its 2018 monitoring program. To select markers of bemitil use, six doses of the supplement (two per day, on three consecutive days) were administrated to six healthy volunteers (three men, three women, 26-49 years). Urine samples were collected before, during and up to 30 days after the first ingestion. Samples were analyzed by means of ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The study revealed that bemitil can be traced in urine as either a parent compound or its glucuronide conjugate, which is more abundant and has a wider detection window.

Detection of bemitil and its metabolite in urine by means of LC–MS/MS in view of doping control analysis

Intensive exercise is related to an increased generation of reactive oxygen species (ROS), the main cause of oxidative stress, as a consequence of higher energy demand [1,2]. In active tissues such as skeletal muscles, ROS activity results mainly from mitochondria damage and may impair the muscle force production. Therefore, many athletes consume antioxidant supplements to suppress muscle fatigue or to facilitate the process of recovery. Whether such antioxidant supplementation has beneficial effects on sport performance and health is a matter of controversy which seems to stem from considerable differences in study designs [3]. Some authors report that antioxidant supplementation, especially a prolonged one, may have deleterious effects on health and sport performance, e.g. by down regulating natural ROS quenching mechanisms or hampering organism adaptation to increased physical exercise [4-8]. Such results are in line with the free radical theory of development which posits that formation of reactive species plays a very important role in development of organisms and their adaptation to environmental changes [9]. Other studies report that antioxidant supplementation may lead to increased sport performance or shortens the process of post-exercise recovery; the effects highly desired by competitive athletes. A common feature of those studies seems to be a short and acute supplementation period, usually a few days or weeks long, which perhaps still allows for triggering the adaptation mechanisms in response to increased production of ROS. These studies are of the main interest of this review.

https://biomedres.us/pdfs/BJSTR.MS.ID.002293.pdf

Krzysztof Grucza

Papers

Analysis for higenamine in urine by means of ultra-high-performance liquid chromatography–tandem mass spectrometry: Interpretation of results

The use of a valid and straightforward method for the identification of higenamine in dietary supplements in view of anti-doping rule violation cases

Detection of bemitil and its metabolite in urine by means of LC–MS/MS in view of doping control analysis

Effects of Supplementation with Glutathione and its Precursors on Athlete Performance

Cocaine abuse out of competition: Occasional or chronic user in sport-Case report.