Asclepiadoideae subfamily (Apocynaceae): ethnopharmacology, biological activities and chemophenetics based on pregnane glycosides

Apocynaceae, one of the largest plant families with over 5.100 widely distributed species, serves as a significant model for evolutionary and biochemical studies. Within this family, compounds such as alkaloids, flavonoids, and terpenoids with potential therapeutic activities have been isolated. Among its subfamilies, Asclepiadoideae is recognized as a rich source of C21 pregnane derivatives. This paper presents a comprehensive review of pregnane glycosides (PG) obtained from Asclepiadoideae, employing an interdisciplinary approach that combines chemophenetics with neural network data analysis to identify promising species and bioactive compounds. A dataset comprising 660 unique PGs and 705 botanical occurrences was compiled for this purpose. The ethnopharmacological aspects, as well as the extraction, isolation, and biological activity of PGs, were analyzed and discussed. Chemophenetic analysis using Self-Organizing Maps (SOM) and phylogeny reconstruction revealed similarities between the Marsdenia-Ceropegiae tribes and highlighted the occurrence of seco and diseco pregnane types predominantly within the Asclepiadeae tribe. Both scaffolds exhibited intriguing structural features, and their derivatives have demonstrated anti-inflammatory and cytotoxic activities. These findings provide valuable insights for future research on these compounds and their medicinal plant sources.