Phylogenetic analysis of traditional medicinal plants: discovering new drug sources from patterns of cultural convergence.

“…we find that certain plant families have a disproportionate number of medicinally useful and psychoactive species, with familial members repeatedly used for similar applications by different cultures from disparate parts of the world.”

Transcript abstract

Medicinal and psychoactive plants have long been used by different cultures worldwide, inspiring the development of modern pharmaceutical drugs including aspirin, digoxin, ephedrine, and morphine. Phylogenetic investigation of these traditional plants along with their medicinal uses and psychoactive effects may shed light on which plant families are used similarly regardless of geographic origin, and may reveal patterns of cultural convergence. Information is assigned to the node, instead of one species at a time, facilitating the study of trait distributions. The confluence of various immigrant groups in New York City (NYC) make it accessible to survey and phylogenetically analyze medicinally important plants in Latin, African, Ayurvedic, Middle Eastern and Chinese cultures and their uses. In a separate study, traditional psychoactive plants and their effects were also phylogenetically analyzed. In both cases, we find that certain plant families have a disproportionate number of medicinally useful and psychoactive species, with familial members repeatedly used for similar applications by different cultures from disparate parts of the world. Apiaceae, Burseraceae, Fabaceae, and Lamiaceae collectively show applications for gastrointestinal, cardiovascular, respiratory, musculoskeletal, and gynecological conditions among diverse immigrant cultures in NYC. Pharmacological traits related to hallucinogenic and sedative potential are also phylogenetically conserved within families such as Cactaceae and Papaveraceae, respectively, while unrelated families that exert similar psychoactive effects also affect similar neurotransmitter systems (i.e., mechanistic convergence), such as modulation of noradrenaline by unrelated stimulant species of Malvaceae and Rubiaceae. These patterns of cultural and mechanistic convergence among traditionally important medicinal and psychoactive plants suggest diverse cultures have independently discovered inherent bioactivity in these plant families and should be further explored in searching for new drug sources. These studies also demonstrate the predictive potential of phylogenetic analyses in uncovering new medicinal applications.