Traditional uses, phytochemistry, pharmacology, and toxicology of Akebiae Caulis and its synonyms: A review

"Mutong" ( in Chinese, and generally known as Akebiae Caulis), which refers to a group of herbal medicines with different biological origins along history, has been used in traditional Chinese medicine for over 2000 years; it is still being frequently used in medicine. In recent decades, Akebiae Caulis has been reported to exhibit apparent toxicity.To clarify the plant species used as Akebiae Caulis and its synonyms, and to summarize their phytochemistry, pharmacology, and toxicology.Academic search engines (Google Scholar, Baidu Scholar, CNKI, Science Direct, Springer Link, SciFinder, PubMed, Web of Science, and EBSCO), ancient Chinese herbals, and modern medical monographs were used to obtain phytochemical, pharmacological, toxicological, and quality control information. Furthermore, a field survey was conducted to clarify the associated species.Akebiae Caulis is derived from eight species belonging to two families. In the 2005 Pharmacopoeia of The People's Republic of China, it has been separated into two categories: Akebiae Caulis and Clematidis Armandii Caulis. Traditionally, Akebiae Caulis has been used to treat conditions such as gonorrhea, edema, and tongue sores. Pharmacological studies have demonstrated the anti-inflammatory, antitumor, antihypertensive, antibacterial, analgesic, and other properties of Akebiae Caulis. Among the species used, Aristolochiae manshuriensis Kom. (Aristolochiaceae) contains aristolochic acid that has raised concerns globally because of its nephrotoxicity.Clarifying the biological origin of traditional herbal medicines is critical for their safe and effective use. The present review revealed that the biological origin of Akebiae Caulis is diverse. The traditional uses, phytochemistry, and pharmacology of Akebiae Caulis indicate that it is a useful medical resource. The diversity of its biological and pharmacological activities is associated with the presence of a large number of chemical substances, among which terpenoids are predominant. Systematic reviews on Akebiae Caulis such as this one would provide solid references for its safe use, as well as drug discovery studies in the future.