Single- and Multiple-dose Pharmacokinetic, Safety and Tolerability Study of Mildronate Injection in Healthy Chinese Subjects Pharmacokinetic of Mildronate Injection

Insights into the pharmacodynamics and pharmacokinetics of meldonium after exposure to acute high altitude

Objective: Meldonium, a well-known cardioprotective drug, has been reported to be protective against pulmonary injury at high altitudes; however, the pharmacodynamics of meldonium in other vital organs under acute high-altitude injury are less investigated and the related pharmacokinetics have not been fully elucidated. Methods and Results: The present study examined the basic pharmacodynamics and pharmacokinetics (PK) in rat exposure to acute high-altitude hypoxia after intragastrical and intravenous pre-administration of meldonium. The results indicate that meldonium can improve acute hypoxia-induced pathological damage in brain and lung tissues, and restore blood biochemistry and routine blood index of heart, liver and kidney tissues under a simulated acute high-altitude environment. Furthermore, compared to the normoxia group, rats exposed to simulated high-altitude hypoxia and premedicated with intragastrical meldonium showed linear kinetics in the dose range of 25-100 mg/kg, with a significantly increase in the area under curve (AUC) and reduced clearance rate. No significant differences in these meldonium of PK parameters were observed with intravenous administration. Additionally, meldonium was involved in the regulation of succinic acid and 3-hydroxypropionic acid. Conclusion: These results will contribute to our understanding of the preclinical PK properties of meldonium and its acute high-altitude protective effects.

Meldonium: Pharmacological, toxicological, and analytical aspects

Meldonium is the active molecule from Mildronate® with similar chemical structure to an amino acid, and it is known as (3-(2,2,2-trimethylhydrazine) propionate) (CAS 76144-81-5). This pharmaceutical substance is approved in Eastern Europe for cerebral and myocardial ischemia and has been on the World Doping Association’s banned substances list since January 2016. The goal of this review is to relate the use of meldonium as a doping agent, considering its pharmacological, toxicological, and analytical aspects. This review is based on the scientific literature from digital platforms. The main mechanism of action of meldonium is based on a decrease in l-carnitine levels and increase of peroxisomes activity in the cytosol. Females were more susceptible to the substance in animal experiments for toxicological tests. There is currently no report in the scientific literature about acute or chronic intoxication cases by meldonium in humans. Based on the literature findings, meldonium showed ergogenic effect in animals and human volunteers. For anti-doping analysis, urine is the biological matrix of choice, and dilute-and-shoot is the most common sample treatment in addition to liquid chromatography–mass spectrometry analysis. Other approaches could be used to determine meldonium levels, mainly for screening tests, such as l-carnitine or gamma-butyrobetaine levels.