Challenges associated with elucidating the mechanisms of the hypocholesterolaemic activity of saponins

Abstract

Saponins are naturally occurring bioactive compounds that are primarily found in plants. Saponins possess a wide range of physiological activities, and their cholesterol-lowering effects are gaining increasing attention. Saponins have considerable potential as pharmaceutical and/or nutraceutical agents in their natural or synthetic forms. Several possible mechanisms have been suggested to explain the hypocholesterolaemic activity of saponins. However, the exact mechanism of this activity remains unclear. With advances in the study of cholesterol homeostasis, this paper reviews the factors that determine the hypocholesterolaemic activity of saponins, especially after their absorption or metabolism in the gastrointestinal tract. A critical review of recent research papers suggests that inadequate information regarding the purification, analysis, and bioavailability of saponins are the major factors that limit the clear elucidation of saponin hypocholesterolaemic activity. Future investigations should characterize the manner in which hypocholesterolaemic activity enhances saponin physiological activity in vivo, which is closely related to saponin bioavailability.

Keywords

• Saponin
• Hypocholesterolaemic activity
• Bioavailability
• Cholesterol absorption