Potassium usnate toxicity against embryonic stages of the snail Biomphalaria glabrata and Schistosoma mansoni cercariae

Abstract

The snail Biomphalaria glabrata is the most important vector for Schistosoma mansoni. Control of this vector to prevent the spread of schistosomiasis is currently performed with the application of a niclosamide molluscicide, which is highly toxic to the environment. Screening of substances that show embryotoxic molluscicidal potential as well as have detrimental effects on cercariae is very relevant for the control of schistosomiasis, as the efficacy of prevention of the disease is increased if it acts as a molluscicide as well as on the cercariae of S. mansoni. The aim of this work was to evaluate the effect of potassium usnate derived from usnic acid on different stages of embryonic development of B. glabrata and on S. mansoni cercariae. After 24 h of exposure, potassium usnate showed embryotoxic activity across all embryonic stages. The values obtained from the LC for the embryonic stages were the following: blastula 5.22 μg/mL, gastrula 3.21 μg/mL, trochophore 3.58 μg/mL, veliger 2.79, and hippo stage 2.52 μg/mL. Against S. mansoni cercariae, it had LC and 100% mortality at concentrations of 2.5 and 5 μg/mL in 2 h of exposure. In conclusion, this is the first report of potassium usnate toxicity on the embryonic stages of B. glabrata and cercariae of S. mansoni, and this study shows the potassium usnate as a promising agent for the control of mansoni schistosomiasis.

Dataset on schistosomiasis control using potassium usnate against Biomphalaria glabrata at different developmental stage and Schistosoma mansoni cercariae

“… This text presents complementary data corresponding to schistosomiasis mansoni׳s vector control and toxicity on Schistosoma mansoni cercariae using potassium usnate. This information support our research article “Potassium Usnate Toxicity Against Embryonic Stages of the Snail Biomphalaria glabrata and Schistosoma mansoni Cercariae” [1] , and focuses on the analysis of the detailed data regarding the different concentrations of potassium usnate and their efficiency to B. glabrata mortality and non-viability and S. mansoni cercariae mortality etiologic agent of the disease. …”

“…Lima, Potassium usnate toxicity against embryonic stages of the snail Biomphalaria glabrata and Schistosoma mansoni cercariae. Acta Tropica [1] …”

Usnic Acid Potassium Salt: Evaluation of the Acute Toxicity and Antinociceptive Effect in Murine Model

“…Natural derivatives are important sources of raw materials in obtaining molecules in the composition and development of promissory compounds, when the aim is the development of new drugs. In addition, they can also allow structural modifications (syntheses) from these substances, potentiating their biological activity, thus leading to an optimization of therapeutic activity [4,18,21,22,23,24,25,31,32]. Therefore, we contribute with the first report of PS-UA obtained from UA isolated from Cladonia substellata (lichen).…”

“…Therefore, it is important to introduce new, effective methods to increase the solubility and dissolution rate of drug candidates in order to improve their oral bioavailability, to increase the predictability of responses, and/or to reduce the dose [18,19,20]. Thus, one of the alternatives for increasing the bioavailability of UA is to chemically modify it in the form of usnic acid potassium salt (PS-UA), which optimizes not only its solubility but also its toxicity without decreasing its biological potential [21,22,23,24,25]. Although lichen substances are widely mentioned in folk medicine, studies of their chemically modified bioactive molecules are incipient.…”

“…Although lichen substances are widely mentioned in folk medicine, studies of their chemically modified bioactive molecules are incipient. UA in the form of PS-UA, inhibits invasion and metastasis in colorectal cancer [21]; its efficiency against adult snails [22] and different embryonic stages of Biomphalaria glabrata (vector of schistosomiasis) [23,24] has been demonstrated, as well as good in vitro activity against adult couples worms of Schistosoma mansoni at concentrations of 100 and 50 μM in a 24-h interval. With respect to cytotoxicity, PS-UA was non-toxic to peripheral blood mononuclear cells (PBMC) at the same concentrations [25].…”