Jornal de doenças infecciosas e terapia

Abstrato

Medicinal Plants, an Important Reserve of Antimycobacterial and Antitubercular Drugs: An Update

María Adelina Jiménez-Arellanes, Gabriel Gutiérrez-Rebolledo, Susana Rojas-Tomé and Mariana Meckes- Fischer

Background: Tuberculosis is a global and serious Public Health problem due to the increase of multidrugresistant and extensively drug-resistant cases; as a result, diverse research groups worldwide are focusing their efforts on finding novel antituberculous agents that can provide greater effectiveness, less toxicity and having a specific mechanism of action, possibly being coadjuvants in the treatments currently prescribed.

Methods: The present review covers the literature published concerning secondary metabolites of those Mexican medicinal plants and secondary metabolites isolated from them showing in vitro antimycobacterial activity with MIC <50 μg/mL against sensitive and MDR M. tuberculosis strains as well as against NTM strains. The review also includes a special section for those natural compounds or plant extracts with antitubercular activity evaluated an in vivo experimental tuberculosis model.

Results: Some pure compounds with MIC<25 μg/mL are: 2-oxo-14-(3´,4´-methylenedioxyphenyl) tetradecane, 2- oxo-16-(3´,4´-methylenedioxyphenyl)hexadecane, 5,6-dehydro-7,8-dihydro methysticin, cepharanone B and piperolactam A (from Piper sanctum), suberosin (from Arracacia tolucensis) and leubethanol (from Leucophyllum frutescens). In addition, (-)-licarin A (from Aristolochia taliscana) was active against M. tuberculosis H37Rv, 12 MDR M. tuberculosis clinical isolates and four non-tuberculous mycobacteria. On the other hand, the antitubercular activity of (-)-licarin A, ursolic acid and oleanolic acid has been determined in a TB murine experimental in vivo model; (-)-licarin A reduces the bacterial lung load and the percentage of pneumonia in animals infected with M. tuberculosis H37Rv and MDR M. tuberculosis. The mixture of ursolic and oleanolic acids showed a significant reduction of bacterial loads and pneumonia in animals infected with M. tuberculosis H37Rv and MDR M. tuberculosis.

Conclusion: Since (-)-licarin A, ursolic acid and oleanolic acid have been evaluated as antitubercular compounds, these metabolites are candidates proposed feasible to be proposed for development of antituberculosis drugs.