Genus Senecio in China: A review on its traditional uses, phytochemistry, pharmacology, and toxicity

The genus Senecio comprises approximately 1500 species worldwide, with over 60 species distributed throughout China. These plants have been widely used in traditional Chinese medicine to treat various conditions including inflammation, eye diseases, vaginal trichomoniasis, and acute urinary tract infections.

This review aims to provide a comprehensive analysis of the geographical distribution, traditional uses, phytochemical composition, pharmacological activities, and toxicology of medicinally important Senecio species in China. Furthermore, we critically evaluate future research directions to provide valuable insights for subsequent research and development of this genus.

We collected and analyzed relevant literature from 1963 to 2023 using multiple databases including PubMed, Web of Science, ScienceDirect, Google Scholar, Elsevier, Sci Finder, CNKI, and Wan fang. We also examined doctoral and master's theses, the Chinese Pharmacopoeia (2020 edition), and various Materia Medica monographs. Plant nomenclature was verified using "The Plant List" (http://www.theplantlist.org).

As traditional Chinese medicinal herbs, Senecio plants are commonly employed to treat acute inflammation, eye diseases, and pruritus. To date, 217 chemical constituents have been isolated and characterized from medicinal Senecio species, primarily including alkaloids, sesquiterpenes, flavonoids, phenolic acids, jacaranones, and volatile oils, along with minor amounts of lignans and steroids. Among these compounds, pyrrolizidine alkaloids (PAs) and furoeremophilanes represent the characteristic chemical constituents of the genus. Extensive studies have demonstrated that extracts and isolated compounds from Senecio plants exhibit diverse pharmacological activities, including antibacterial, anti-inflammatory, antitumor, antiviral, antioxidant, hepatoprotective, and analgesic effects. However, Senecio species also demonstrate specific toxicity profiles, primarily manifesting as acute toxicity, hepatotoxicity, and reproductive toxicity, with PAs identified as the main toxic components.

Phytochemical and pharmacological studies have established Senecio species as valuable medicinal plants with significant bioactive properties. However, research has focused primarily on a limited number of species, necessitating comprehensive investigation of other species to identify additional medicinal candidates. Additionally, given that Senecio species generally contain toxic unsaturated PAs, with variations in both types and concentrations among different species, studying their toxic components and content profiles remains a priority for future research.