Leonurine: A Multifaceted Bioactive Alkaloid—From Pharmacological Mechanisms to Clinical Translation: A Narrative Review

Abstract

Background: Leonurine (LEO), a bioactive alkaloid derived from the Leonurus genus, exhibits diverse pharmacological activities including uterotonic, antioxidant, anti-inflammatory, antiapoptotic, Antitumor, and vasoprotective effects. This review aims to provide a comprehensive overview of LEO's pharmacokinetics, pharmacological mechanisms, toxicological profile, and clinical potential, while identifying current limitations and future research directions. Methods: A structured literature review was conducted using scientific databases including PubMed, Scopus, and Web of Science. Relevant preclinical and clinical studies on LEO were selected based on keywords such as “Leonurine,” “pharmacology,” “toxicity,” and “clinical trials.” Data were synthesized to summarize LEO's extraction, biosynthesis, pharmacokinetics, pharmacodynamics, and translational potential. Results: LEO shows rapid absorption but low oral bioavailability (2.21%) due to extensive first-pass metabolism. It preferentially distributes to metabolically active organs such as the liver, kidneys, and heart. Pharmacologically, LEO demonstrates therapeutic efficacy in gynecological, cardiovascular, neurological, and oncological conditions through modulation of oxidative stress, inflammatory mediators, and apoptosis-related pathways. Preclinical studies report a favorable safety profile at therapeutic doses, although toxicity has been observed at higher concentrations, especially with crude extracts. Ongoing formulation efforts such as nanoparticles and prodrugs aim to enhance its pharmacokinetic properties. Conclusion: Leonurine holds considerable promise as a multi-target therapeutic agent. However, successful clinical translation will require structural optimization, improved drug delivery strategies, detailed mechanistic studies, and rigorous human trials. Addressing these gaps may position LEO as a novel candidate in evidence-based phytotherapy and modern drug development.