Effects of a solid formulation containing lectin-rich fraction of Moringa oleifera seeds on egg hatching and development of Aedes aegypti larvae.

The measures currently used to minimize the spread of arboviruses, comprising dengue, Chikungunya, and Zika virus, involve controlling the size of population of the mosquito Aedes aegypti. However, the search for formulations containing new insecticides is gaining pace due to reports of mosquito populations showing resistance to commonly used compounds. In this study, tablets containing a protein fraction of Moringa oleifera seeds enriched in the WSMoL lectin, known to show larvicidal and ovicidal activities against A. aegypti, were developed. The compatibility between the fraction and the excipients used in obtaining the tablets was evaluated by thermogravimetry (TG), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) absorption spectroscopy. The larvicidal and ovicidal activities of the resulting tablets [5%, 10%, and 15% (w/w) of the fraction] were evaluated, as well as their effect on mosquito oviposition. Assays were also performed using a placebo tablet. According to the TG, DSC, and FTIR results, the protein composition of the fraction did not change when mixed with the components of the formulation. Tablets containing 10% and 15% WSMoL-rich fraction caused mortality of 42.5% and 95% of the larvae after 48 h, respectively, with larvae incubated with these tablets showing reduced acetylcholinesterase activity. All tablets inhibited egg hatching after 72 h (36-74%), and tablets containing 15% fraction were found to exert a repellent effect on oviposition. Our results show that the formulation developed in this study interfered with the life cycle of A. aegypti, and thus show potential for use in the control of this mosquito.

Recent strategies for the development of oral medicines for the treatment of visceral leishmaniasis.

Considered prevalent in many countries on five continents, especially in low-income regions, leishmaniasis is a neglected tropical disease classified by World Health Organization as one of the diseases for which the development of new treatments is a priority. It is an infectious disease caused by protozoa of the genus Leishmania, whose species may cause different clinical manifestations, such as cutaneous and visceral leishmaniasis (VL). Treatment is exclusively by drug therapy, as it has not been possible to develop vaccines yet. Currently available drugs are not fully effective in all cases; they have parenteral administration and exhibit a number of serious and very common adverse effects. The only oral drug available is expensive and it is not available in many endemic countries. Injectable administration is the main problem of treatments, since it requires patients to go to health centers, hospitalization and professional administration, which are conditions that are not adapted to the reality of the poverty conditions of patients with the disease. In this context, the development of an oral medicine has become a focus as it may solve many of these issues. Based on this scenario, this review aimed to investigate which therapeutic alternatives have been studied for the development of oral drugs directed to the treatment of human VL.