Traditional uses, chemical composition and pharmacological activities of Alstonia R. Br. (Apocynaceae): A review

Alstonia R. Br. (Apocynaceae) is widely used in the traditional therapeutic systems. Due to its rich natural active ingredients, it is used in China, India, Thailand, Malaysia, Philippines, Africa, Australia and other countries to treat malaria, dysentery, asthma, fever, epilepsy, skin diseases, snake bites, and so on. The aim of this review is to describe in detail the botanical properties, traditional uses, chemical compositions, pharmacological activities and toxicity of the genus Alstonia for analyzing the value of this plant in clinical applications. There was information on the genus Alstonia collected through the internet searches such as Baichain Library, Web of Science, China National Knowledge Infrastructure (CNKI), Baidu Scholar, PubMed, Wan Fang Database and ACS, etc. The keywords used include genus Alstonia, folk medicinal uses, botanical studies, chemical composition, pharmacological activities, bioactivities and other relevant terminology. The scientific names and geographic location of the genus Alstonia were provided in the Subject Database of the Flora of China, the Plant List (www.theplantlist.org), the WFO Plant List (www.worldfloraonline.org) and the World Checklist of Selected Plant Families (http://wcsp.science.kew.org/qsearch.do). Currently, at least 400 compounds were isolated from genus Alstonia, including alkaloids, triterpenes, flavonoids, volatile oils, phenolic acids, etc. Through extensive pharmacological experiments, it was demonstrated that genus Alstonia had good pharmacological effects in vitro and in vivo, including β2AR, vasodilatory, antifungal, antineoplastic, antiplasmodial, anti-inflammatory, antibacterial, antioxidant, analgesic, and radioprotective activities, etc. Many studies also confirmed that the combination of the genus Alstonia with other traditional Chinese medicines could improve effectiveness. This review demonstrates that the genus Alstonia has high clinical application and medicinal value, which will bring the attention of pharmacologists and clinicians to the territory of natural products Additionally, bioactivity-related mechanisms and structure–activity relationships of chemical components are not clear. Only by bridging the gap between bioactivity-related mechanisms and structure–activity relationships of chemical components can the development of Alstonia plants be further promoted.