Evidence for the Safe Use of the Extract from the Brazilian Arnica, <i>Solidago chilensis</i> Meyen, in Primary Health Care

Abstract

In Brazil, the National Policy on Medicinal Plants has stimulated the use of plants in primary health care, validating the traditional medicine and pointing to the lack of a consistent set of evidence that supports their uses and indications by ethnobotany and ethnopharmacology. This paper aims to make a systematic review of the scientific literature to gather evidence on indications and safety of use of extracts of Solidago chilensis . The bibliographic research was carried out using terms derivate from the title, and all the published papers were downloaded, covering at least the last five years, and it was focused on preclinical and clinical studies with extracts of S. chilensis in the databases of Web of Science, BIREME, SciELO, PubMed, Scirus and Highwire. Phytochemical analysis carried out on many studies showed that among the chemical constituents of S. chilensis are sesqui- and diterpenes, flavonoids and other substances, and the diterpene solidagenone was identified as a marker of the extract that has demonstrated gastroprotective activity in different experimental models of ulcer induced in animals without signs of toxicity at doses above 600 mg/kg. Another studies show that the anti-inflammatory effect in rats has been given by inhibiting the exudation of leukocytes, especially neutrophils, as well as through inhibition of myeloperoxidase, adenosine deaminase, and tumor necrosis factor-α (TNF-α), decreased induction of nitric oxide synthesis and levels of interleukin-1β. Studies show that solidagenone at a concentration of 100 mg/kg showed activity similar to lansoprazole (20 mg/kg), the effect occurs without changes in the gastric mucosa or on acid secretion. The aqueous and alcoholic extracts showed anti-inflammatory activity and may act in a satisfactory way in cases involving the inflammatory response, such as injuries due to trauma, repetitive stress, pain, and healing. The inhibition of anti-inflammatory response is on the base of all these described effects. In spite of the fact that S. chilensis has been used since ancient times in Brazilian traditional medicine, and the existence of preclinical pharmacological end toxicological evidence for its efficacy as an inhibitor of anti-inflammatory response, we could find only a single clinical trial study carried out in treating lumbago. In this lack of clinical pharmacology and toxicology evidence for its uses, its safety and therapeutic indications are guaranteed, up to this moment, by traditional knowledge.