Bioavailability and Pharmacokinetics of Plant Metabolites in Neurotherapeutics

The therapeutic potential of neurotherapeutics derived from plants relies on their bioavailability and pharmacokinetics, which can explain how a drug is absorbed, distributed, metabolized, and excreted within the body. Although plant secondary metabolites, such as flavonoids, alkaloids, terpenoids, and polyphenols, hold great promise for neuroprotection, clinical translation is often difficult due to poor solubility, low stability, rapid metabolism, and limited ability to cross the blood– brain barrier. This chapter discusses complex mechanisms affecting the bioavailability and pharmacokinetics of neurotherapeutic phytochemicals, focusing on their structural characteristics, delivery systems, and interaction with metabolic enzymes. It also discusses the strategies enhancing brain-targeted delivery, among which are nanoparticle-based carriers, lipid emulsions, and prodrug formulations. This chapter investigates into the mechanisms behind bioavailability and pharmacokinetics of neurotherapeutic phytochemicals and focuses on the characteristics at a structural level, mode of delivery, and interaction with metabolic enzymes. As such, it covers ways to improve targeted delivery to the brain, employing nanoparticle-based carriers, lipid emulsions, and prodrug formulations. The purpose of this chapter is to provide a comprehensive overview of recent development so that the laboratory finding can be bridged by clinical application for insights in optimizing the therapeutic potential of plant-derived neuropharmacological agents for brain health.