Leishmanicide potential of Antarctic microbial products: pharmacological evaluation of bacterial pigmented extracts and systematic review of anti-Leishmania activity of fungal metabolites
Bioprospecting. Extremophiles. Natural products. Leishmaniasis. Antiparasitic Agents.
Diseases like leishmaniasis remain neglected by the pharmaceutical industry. Consequently, the treatment for this disease is out of date, leaving countless affected individuals unattended. To reverse the impact of this abandonment, it is essential to search for new prototypes of safer drugs for the treatment of leishmaniasis. Therefore, the bioprospecting of natural products, especially microbial products from extreme environments, represents an excellent starting point. From this perspective, the present study investigated the leishmanicidal activity of extracts of bacteria isolated from Antarctica, as well as carried out a systematic review about the leishmanicidal activity of fungal metabolites. In all, eight bacterial isolates obtained from soil samples and Antarctic lichens were grown in nutrient broth for seven days at 15 ° C for biomass production. The intracellular pigmented metabolites were extracted with methanol and subsequently the obtained extractive solutions were dried in a vacuum desiccator. The cytotoxicity of the extracts will be evaluated against the lineage of macrophages J774.A1 by means of the tetrazolium salt reduction (MTT) assay and the antiparasitic action evaluated on macrophages infected with Leishmania spp. as to the rate of infection and the multiplication of intracellular parasites. The systematic review aimed to identify through the PubMed, Lilacs and Scielo databases, the existing evidence in the literature regarding the efficacy of the leishmanicidal activity of fungal bioproducts that represent new starting points for the advancement of leishmaniasis pharmacotherapy. Among the selected studies, 53 (89.8%) carried out exclusively in vitro assay, while only 2 (3.4%) carried out exclusively in vivo assay. Another 4 (6.8%) performed the two analysis methodologies (in vitro and in vivo). Together, the evidence reported by the publications gathered in the review, indicate in the prospecting of fungal bioproducts a promising path in the fight against leishmaniasis.