Dr. Eliana Nakano (Instituto Butantan São Paulo)


Dr. Eliana Nakano

Instituto Butantan São Paulo

Brazil

Dr. Eliana Nakano is a Researcher in the Parasitology Lab at São Paulo's Instituto Butantan, researching new drugs to treat schistosomiasis, mainly from natural sources. In recent research, Dr. Nakano has worked on exploring the role of Brazilian marine macroalgae in schistosomiasis control. In addition, Dr. Nakano has also been developing research on environmental mutagenesis and ecotoxicology using molluscs as bioindicators. Ahead of her presentation at ISNTD d³ 2018, the annual conference by the ISNTD on drug discovery and diagnostics, we catch up with Dr. Nakano and find out more about her current research, ongoing gaps and challenges in the control of schistosomiasis and future collaborations needed to accelerate research in this field.

You will be presenting at ISNTD d³ 2018 about the potential use of Brazilian marine macroalgae in schistosomiasis control - what have been some of the major challenges in current control strategies that you are trying to address?

By searching for new compounds to schistosomiasis control, we aim to increase the current chemical arsenal available for this disease. There is a single drug, praziquantel, to the treatment and control of schistosomiasis, and for the control of host snails, a single chemical moluscicide, niclosamide, is available. With the choice for a natural source in our studies, we aim to explore the potential of our biodiversity of producing metabolites with biological activity.

What inspired you to explore algae as a source of active compounds in parasite control? Do you also envisage a role in mollusc control?

Brazil has approximately 770 algae species distributed along a 7,367 km of coastline with diverse ecological conditions, which suggests a high biotechnological potential. Diverse biological activities have been reported for several algae species; however, there is no data on the schistosomicidal activity for any algae species.

In a previous study, we have detected the moluscicidal activity of a Brazilian algae species, which showed that algae could be explored in our bioprospection studies (Miyasato, P A; Kawano, T; Freitas, JC; Berlinck, RGS; Nakano, E ; Tallarico, LF. Molluscicidal activity of some marine substances against the snail Biomphalaria glabrata (Mollusca, Planorbidae).

Later, in 2013, we started a partnership with the group of Prof. Pio Colepicolo from Chemistry Institute of São Paulo University, which works with native and non-native macro and microalgae species in diverse aspects, including Taxonomy and Chemistry. This collaboration has allowed us to access a large variety of algae species and to isolate and characterize active compounds.

Regarding mollusc control, in fact, our studies on schistosomiasis have started with the search for molluscicides in the early 80’s. Since the establishment of the whole Schistosoma mansoni cycle in our laboratory, all species are screened for molluscicidal and schistosomicidal activity.

What are the next steps which you will be exploring and do you currently have ongoing research to refine your findings?

Our aim is at designing and developing novel prototypes as potentially drug candidates to schistosomiasis control. In order to reach that goal, firstly, the chemical framework of bioactive compounds isolated from the Laurencia aldingensis crude extract (dihydroceramide was one of them) has been used as reference to synthesize novel analogues. After purification and characterization, the novel compounds will be experimentally screened against the parasite and, then, the structure/property-activity relationships will be explored applying molecular modelling, chemometrics, and computational chemistry approaches. The establishment of SAR will allow the designing of novel and more promising compounds (new chemical enities).

This is the rationale of our current project.

Are similar algae growing in other countries around the world and will you seek to extend screening globally?

Yes. There are similar seaweeds growing in different countries. Many species from different genre (like Gracilaria, Palisada, Ochtodes, Cryptonemia, Pterocladiella, p. ex.) are spreadly distributed in the Atlantic Ocean or around the world. But Laurenciella sp. and the one we still call Laurencia aldingensis are endemic from Brazilian coast, which increases our interest in the studies. By now, we are not thinking in extending our studies globally. The only study with non native algae species may be a screening with Mozambique species, since there is a post-graduate student, from the Pedagogic Manica University, doing her PhD in our project.