Meldonium Supplementation in Professional Athletes: Career Destroyer or Lifesaver?

Meldonium is a substance with known anti-anginal effects demonstrated by numerous studies and human clinical trials; however, it does not possess marketing authorization within the European Union, only in ex-Soviet republics. Since 2016, meldonium has been included by the World Anti-doping Agency (WADA) on the S4 list of metabolic modulators. In performance athletes, meldonium is now considered a doping agent due to its capacity to decrease lactate production during and after exercise, its capability to enhance the storage and utilization of glycogen, and its protective action against oxidative stress. Together, these attributes can significantly improve aerobic endurance, cardiac function, and capacity as well as shorten recovery times (allowing higher intensity training), thereby enhancing performance. The purpose of this review is to highlight the most important mechanisms underlying the protective effect of meldonium against mitochondrial dysfunction (MD), which is responsible for oxidative stress, inflammation, and the cardiac changes known as "athletic heart syndrome." Meldonium acts as an inhibitor of γ-butyrobetaine hydroxylase (BBOX), preventing the de novo synthesis of carnitine and its absorption at the intestinal level via the organic cation/carnitine transporter 2 (OCTN2) and directing the oxidation of fatty acids to the peroxisomes. The decrease in mitochondrial ß-oxidation of fatty acids leads to a reduction in lipid peroxidation products that cause oxidative stress and prevent the formation of acyl/acetyl-carnitines involved in numerous pathological disorders. Given the recent findings of the potentially detrimental effects of prolonged high-intensity exercise on cardiovascular health and coronary atherosclerosis, there may be legitimate arguments for the justification of the use of substances like meldonium as protective supplements for athletes.

Assessing ß-Sitosterol Levels in Dietary Supplements for Benign Prostatic Hyperplasia: Implications for Therapeutic Efficacy.

Introduction Benign prostatic hyperplasia (BPH) is a prevalent condition among aging men that affects their life quality due to urinary symptoms. Current pharmacologic treatments, often lead to sexual dysfunction, so dietary supplements (DS) containing plant-based compounds such as ß-sitosterol (SIT) are preferred. DS are highly accessible and widely used, but poorly regulated, so often patients are victims of fraud. The use of DS to treat BPH symptoms is questionable, and this may be due not to the efficacity of the active compound but to the quality of commonly available DS. Aim This study aimed to assess the concentration of SIT in DS available on the market and evaluate whether the concentration of the active compound at the recommended dosage is sufficient to elicit beneficial effects in BPH. Method An HPLC-UV method based on direct saponification and acid hydrolysis was developed for the quantification of free and conjugated SIT in DS. The concentration of SIT in various DS was determined and compared with the one declared on the label. Results The chromatographic analysis confirmed the presence of SIT in all the DS but also showed a considerable variability of SIT content among DS, with only one product meeting the necessary concentration to bring potential benefits in BPH. Conclusion The study highlights inconsistencies in SIT content among DS and the importance of DS containing a standardized extract of SIT. Quality control measures are imperative to ensure that consumers receive effective and safe SIT-based DS to manage BPH symptoms. Further research is needed to establish standardized dosages and to evaluate their long-term efficacy and safety.

Fructose-induced hyperuricaemia - protection factor or oxidative stress promoter?

Accumulating evidence suggests that dietary fructose may play a role in the hyperuricaemia development, but the precise mechanism remains unclear. Hyperuricaemia is characterised by excessive production and deposition of urate crystals, and the metabolism of fructose has been implicated in the elevation of serum urate levels. The association between fructose intake and the risk of hyperuricaemia is explained by the metabolism of fructose in the liver, small intestine, and kidney. Many studies have confirmed the correlation between fructose consumption and an increased risk of developing hyperuricaemia, but more prospective studies to fully elucidate the role of fructose intake in the pathogenesis of hyperuricaemia are needed. It is important to note that maintaining a balanced diet, and lifestyle is crucial when considering fructose intake. Limiting the consumption of products high in added sugars and maintaining a healthy weight can contribute to reducing the risk of hyperuricaemia and associated health complications.

Biochemical Aspects That Lead to Abusive Use of Trimetazidine in Performance Athletes: A Mini-Review.

Trimetazidine (TMZ), used for treating stable angina pectoris, has garnered attention in the realm of sports due to its potential performance-enhancing properties, and the World Anti-Doping Agency (WADA) has classified TMZ on the S4 list of prohibited substances since 2014. The purpose of this narrative mini-review is to emphasize the biochemical aspects underlying the abusive use of TMZ among athletes as a metabolic modulator of cardiac energy metabolism. The myocardium's ability to adapt its energy substrate utilization between glucose and fatty acids is crucial for maintaining cardiac function under various conditions, such as rest, moderate exercise, and intense effort. TMZ acts as a partial inhibitor of fatty acid oxidation by inhibiting 3-ketoacyl-CoA thiolase (KAT), shifting energy production from long-chain fatty acids to glucose, reducing oxygen consumption, improving cardiac function, and enhancing exercise capacity. Furthermore, TMZ modulates pyruvate dehydrogenase (PDH) activity, promoting glucose oxidation while lowering lactate production, and ultimately stabilizing myocardial function. TMZs role in reducing oxidative stress is notable, as it activates antioxidant enzymes like glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD). In conclusion, TMZs biochemical mechanisms make it an attractive but controversial option for athletes seeking a competitive edge.

Stability of Oral Liquid Dosage Forms in Pediatric Cardiology: A Prerequisite for Patient's Safety-A Narrative Review.

The development of safe and effective pediatric formulations is essential, especially in therapeutic areas such as pediatric cardiology, where the treatment requires multiple dosing or outpatient care. Although liquid oral dosage forms are considered the formulation of choice given the dose flexibility and acceptability, the compounding practices are not endorsed by the health authorities, and achieving stability can be problematic. The purpose of this study is to provide a comprehensive overview of the stability of liquid oral dosage forms used in pediatric cardiology. An extensive review of the literature has been performed, with a particular focus on cardiovascular pharmacotherapy, by consulting the current studies indexed in PubMed, ScienceDirect, PLoS One, and Google Scholar databases. Regulations and guidelines have been considered against the studies found in the literature. Overall, the stability study is well-designed, and the critical quality attributes (CQAs) have been selected for testing. Several approaches have been identified as innovative in order to optimize stability, but opportunities to improve have been also identified, such as in-use studies and achieving dose standardization. Consequently, the information gathering and the results of the studies can be translated into clinical practice in order to achieve the desired stability of liquid oral dosage forms.

Is Hypovitaminosis D a Risk Factor for Heart Failure?

BACKGROUND: Several studies in recent years have shown the association between vitamin D levels and heart failure. Vitamin D deficiency is related to increased cardiovascular morbidity and mortality, with a higher risk of developing heart failure. In this systematic review, we aimed to assess recent studies that analyzed vitamin D deficiency and heart failure in adult and pediatric populations. (2) Methods: We conducted a systematic search for studies published in the following databases: PubMed and Scopus from January 2012 to October 2022. (3) Results: Most observational studies that were included found a significant association between hypovitaminosis D and heart failure. However, the beneficial role of vitamin D supplementation is still controversial due to the lack of randomized controlled trials. (4) Conclusions: Vitamin D may play an important role as a cardiovascular marker in heart failure patients. More well-designed studies are needed to investigate the relationship between vitamin D and heart failure and to determine if vitamin D supplementation could improve long-term outcomes.

Cannabidiol: Bridge between Antioxidant Effect, Cellular Protection, and Cognitive and Physical Performance.

The literature provides scientific evidence for the beneficial effects of cannabidiol (CBD), and these effects extend beyond epilepsy treatment (e.g., Lennox-Gastaut and Dravet syndromes), notably the influence on oxidative status, neurodegeneration, cellular protection, cognitive function, and physical performance. However, products containing CBD are not allowed to be marketed everywhere in the world, which may ultimately have a negative effect on health as a result of the uncontrolled CBD market. After the isolation of CBD follows the discovery of CB1 and CB2 receptors and the main enzymatic components (diacylglycerol lipase (DAG lipase), monoacyl glycerol lipase (MAGL), fatty acid amino hydrolase (FAAH)). At the same time, the antioxidant potential of CBD is due not only to the molecular structure but also to the fact that this compound increases the expression of the main endogenous antioxidant systems, superoxide dismutase (SOD), and glutathione peroxidase (GPx), through the nuclear complex erythroid 2-related factor (Nrf2)/Keep1. Regarding the role in the control of inflammation, this function is exercised by inhibiting (nuclear factor kappa B) NF-κB, and also the genes that encode the expression of molecules with a pro-inflammatory role (cytokines and metalloproteinases). The other effects of CBD on cognitive function and physical performance should not be excluded. In conclusion, the CBD market needs to be regulated more thoroughly, given the previously listed properties, with the mention that the safety profile is a very good one.

Caffeine and Its Antioxidant Properties-It Is All about Dose and Source.

Caffeine is the most frequently used substance with a central nervous system stimulant effect, but its consumption is most often due to the intake of foods and drinks that contain it (coffee, tea, chocolate, food supplements with plant extracts of Guarana, Mate herba, Cola nuts). Due to its innocuity, caffeine is a safe xanthine alkaloid for human consumption in a wide range of doses, being used for its central nervous stimulating effect, lipolytic and diuresis-enhancing properties, but also as a permitted ergogenic compound in athletes. In addition to the mechanisms that explain the effects of caffeine on the targeted organ, there are many proposed mechanisms by which this substance would have antioxidant effects. As such, its consumption prevents the occurrence/progression of certain neurodegenerative diseases as well as other medical conditions associated with increased levels of reactive oxygen or nitrogen species. However, most studies that have assessed the beneficial effects of caffeine have used pure caffeine. The question, therefore, arises whether the daily intake of caffeine from food or drink has similar benefits, considering that in foods or drinks with a high caffeine content, there are other substances that could interfere with this action, either by potentiating or decreasing its antioxidant capacity. Natural sources of caffeine often combine plant polyphenols (phenol-carboxylic acids, catechins) with known antioxidant effects; however, stimulant drinks and dietary supplements often contain sugars or artificial sweeteners that can significantly reduce the effects of caffeine on oxidative stress. The objective of this review is to clarify the effects of caffeine in modulating oxidative stress and assess these benefits, considering the source and the dose administered.