Antitubercular and anti-inflammatory properties screening of natural products from Plectranthus species.

Future Med Chem. 2018 Jun 29. doi: 10.4155/fmc-2018-0043. [Epub ahead of print] Andrade JM1, Custódio L2, Romagnoli A3, Reis CP1,4, Rodrigues MJ2, Garcia C1, Petruccioli E3, Goletti D3, Faustino C4, Fimia GM3,5, Rijo P1,4. Author information 1 Universidade Lusófona's Research Center for Biosciences and Health Technologies (CBIOS), Campo Grande 376, 1749-024 Lisbon, Portugal. 2 Center for Marine Sciences (CCMAR), University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal. 3 National Institute for the Infectious Diseases 'Lazzaro Spallanzani', Via Portuense, 292, 00149 Rome, Italy. 4 Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon (ULisboa), Av. Prof. Gama Pinto, 1649-003 Lisbon, Portugal. 5 Department of Biological and Environmental Sciences and Technologies (Di.S.Te.B.A.), University of Salento, Lecce, Italy. Abstract AIM: Confirm the use of Plectanthus spp. plants in traditional medicine, particularly as anti-inflammatory and anti-infective agents. MATERIALS & METHODS: Compounds previously isolated from Plectranthus spp. were studied for their anti-inflammatory activity using the SNAP assay and RAW 264.7 cells, by the quantification of nitric oxide. An halimane diterpene and its derivatives were tested in infected macrophages with M. tuberculosis H37Rv, using CFU counts assay, at their minimum inhibitory concentration values. Results: The isolated compounds tested at noncytotoxic concentrations, did not reveal nitric oxide scavenging in the S-nitroso-N-acetylpenicillamine and the cellular assays. On the other hand, promising results were obtained regarding one semisynthetic halimane derivative (11R*,13E)-halima-5,13-diene-11,15-diol), previously prepared (2.1 × 105 CFU/mL), with an effect similar to the antitubercular drugs ethambutol (2.0 × 105 CFU/mL) and isoniazid (1.2 × 105 CFU/mL). CONCLUSION: The present report demonstrates the relevance of Plectranthus spp. in medicinal chemistry drug development for TB and other infective respiratory complaints. Also, this work suggests that further studies involving other inflammatory mediators are needed to validate the anti-inflammatory use of these medicinal plants. KEYWORDS: Mycobacterium tuberculosis; Plectranthus spp.; SNAP; anti-inflammatory; terpenoids; tuberculosis PMID: 29957070 DOI: 10.4155/fmc-2018-0043