Phytomedicine Plus (Nov 2022)
Medicinal plants used in the treatment of asthma in different regions of Brazil: A comprehensive review of ethnomedicinal evidence, preclinical pharmacology and clinical trials
Abstract
Background: Medicinal plants can be important allies in improving the quality of life of asthmatic patients, providing a natural alternative to synthetic drugs that have various side effects. In this context, several species found in Brazil have been indicated for the treatment of asthma in ethnobotanical and ethnopharmacological surveys. Purpose: Gather, for the first time, information from the literature on the Brazilian flora used for the treatment of asthma and identify the species that have already been investigated in preclinical and clinical studies. Study design: A comprehensive review of the literature on medicinal plants used in the treatment of asthma in different regions of Brazil. Methods: Literature was retrieved from Google Scholar, PubMed®, SciELO and ScienceDirect® databases, since the first report on the traditional use of plants with medicinal properties for the treatment of asthma in Brazil in 1983. The scientific names of the species were checked in The Plant List©. Results: According to the scientific documents analyzed, a total of 188 species distributed in 63 families are used for the treatment of asthma by traditional communities in Brazil. The states with the highest number of indications for use were Piauí (11.01%) and Ceará (9.17%). The most representative families in number of species were Fabaceae (24 spp.), Lamiaceae (23 spp.) and Asteraceae (19 spp.). In general, the leaves (37%) were the parts most used in traditional preparations. It was observed that 31 species had their in vivo antiasthmatic activity reported in the literature, while only 11 were evaluated in randomized clinical trials with asthmatic patients. Coumarin, bixin, mangiferin, rosmarinic acid, anthraquinone, 6-shogaol, oroboside, demethylwedelolactone, wedelolactone, stigmast-5,22‑dien-3β-ol, umbelliferone and quercetin were effective in different experimental models of asthma. In a clinical trial, 1,8-cineol showed clinically relevant anti-inflammatory activity and offers new perspectives for its long-term therapeutic use in airway diseases, such as asthma. Conclusions: Altogether, herbal preparations made from medicinal plants have strategic importance for the development of new drugs aimed at the treatment of asthma, but it is important to consider the need to identify the molecular targets of action and toxicological aspects.
