Bianchini, Matheus et al. (2021) International Worm Meeting "Thimerosal toxicity in the reproductive system in C. elegans"

Bianchini, Matheus, Kuhn, Eugenia, Pereira, Flavia, Puntel, Robson, Avila, Daiana

[International Worm Meeting, 2021]

Mercury (Hg) is a heavy metal with no biological function, it can be found worldwide, and is presented in organic and inorganic forms. Among the Hg organic compounds is Thimerosal (THIM), which is a vaccine preservative that is used in Brazil. One of the targets of this organomercurial is the dopaminergic system, however it is necessary to know which other systems could be affected by this compound. The objective of the study was to evaluate the toxicity of THIM on the reproductive system of Caenorhabditis elegans. For this study we have used MD 701 [lim-7p::ced-1::GFP + lin-15(+)] transgenic, which were exposed to THIM from the L4 stage for 24H (vehicle, 10, 25, 50 and 75microM). The worms were maintained in NGM (Nematode Growth Medium) plates with UV-inactivated Escherichia coli OP50. After exposure the survival, brood size, egg laying - levamisole induced, egg production and number of germline apoptotic cells were assessed. Our results demonstrate that THIM does not increase mortality rate in C. elegans, at the concentrations tested. However, THIM exposure caused a decrease in brood size and egg laying at all concentrations. We have found an increase in the number of apoptotic cells and in the egg production at the highest concentrations. Therefore, our results suggest that THIM exposure causes reprotoxicity, since there was an impairment on brood size and increase of germline cells apoptosis. In addition, the reduction in egg laying induced by levamisole and the increase in the number of eggs inside the worms indicate a neuromuscular damage. Resulted increased of eggs inside of worms. However, further studies are needed to understand the mechanism by which THIM exerts its toxicity on C. elegans reproductive system.

PILISSAO, LUIZ EDUARDO et al. (2021) International Worm Meeting "Reprotoxicity induced by Acute exposure to Aqueous Root Extract of Peruvian Maca (Lepidium meyenii) in Caenorhabditis elegans"

da Silva, Andressa Tassinari, Avila, Daiana Silva, Rodrigues, Cristiane Freitas, Puntel, Robson Luiz, Paim, Clesio Soldatelli, Porto, Douglas, PILISSAO, LUIZ EDUARDO, Denardin, Cristiane Casagrande, Brabo, Gabriela Rossi

[International Worm Meeting, 2021]

Ethnopharmacological relevance: Maca (Lepidium meyenii) has been used in folk medicine to treat fertility disturbances. However, there are few scientific evidences validating this use or assuring extract safety. Aim of the study: Hence, in this study we tested the reproduction safety of this extract in Caenorhabditis elegans. Materials and Methods: Root maca powder, obtained from local commerce, was used to prepare the aqueous extract. Worms were acutely exposed to maca extracts (40, 120, 240 and 330 mug/mul), based on human consumption of 1g capsules of the same powder. 48h after treatments, assays were conducted. Results: Maca extract caused a significant decrease in total number of eggs and in the number of eggs per worm from. These effects were associated to increased lipid peroxidation, reduced triacylglycerol levels and also vitellogenin-2 expression, besides increase in the number of apoptotic germline cells. We have detected and quantified alkaloids in this maca extract, which presence could be related to this toxicity. Conclusions: Collectively, our data suggest that maca extract exposure causes reproductive toxicity to worms which could be, at least in part, associated to both an increase in apoptosis of germline cells and also to a decrease in vitellogenin expression, needed for egg yolk production, and consequently, successful reproduction.