Inclusion complex of O-allyl-lawsone with 2-hydroxypropyl-ß-cyclodextrin: Preparation, physical characterization, antiparasitic and antifungal activity.

The subclass naphthoquinone represents a substance group containing several compounds with important activities against various pathogenic microorganisms. Accordingly, we evaluated O-allyl-lawsone (OAL) antiparasitic and antifungal activity free and encapsulated in 2-hydroxypropyl-ß-cyclodextrin (OAL MKN) against Trypanosoma cruzi and Sporothrix spp. OAL and OAL MKN were synthesized and characterized by physicochemical methods. The IC50 values of OAL against T. cruzi were 2.4 µM and 96.8 µM, considering epimastigotes and trypomastigotes, respectively. At the same time, OAL MKN exhibited a lower IC50 value (0.5 µM) for both trypanosome forms and low toxicity for mammalian cells. Additionally, the encapsulation showed a selectivity index approximately 240 times higher than that of benznidazole. Regarding antifungal activity, OAL and OAL MKN inhibited Sporothrix brasiliensis growth at 16 µM, while Sporothrix schenckii was inhibited at 32 µM. OAL MKN also exhibited higher selectivity toward fungus than mammalian cells. In conclusion, we described the encapsulation of O-allyl-lawsone in 2-hydroxypropyl-ß-cyclodextrin, increasing the antiparasitic activity compared with the free form and reducing the cytotoxicity and increasing the selectivity towardSporothrix yeasts and the T. cruzi trypomastigote form. This study highlights the potential development of this inclusion complex as an antiparasitic and antifungal agent to treat neglected diseases.

In vitro evaluation of 2-(1H-pyrazol-1-yl)-1,3,4-thiadiazole derivatives against replicative and infective stages of Trypanosoma cruzi.

Current treatment of Chagas disease (CD) is based on two substances, nifurtimox (NT) and benzonidazole (BZ), both considered unsatisfactory mainly due to their low activities and high toxicity profile. One of the main challenges faced in CD management concerns the identification of new drugs active in the acute and chronic phases and with good pharmacokinetic profiles. In this work, we studied the bioactivity of twenty 2-(1H-pyrazol-1-yl)-1,3,4-thiadiazole derivatives against Trypanosoma cruzi epimastigotes and trypomastigotes. We identified seven derivatives with promising activity against epimastigote forms with IC50 values ranging from 6 µM to 44 µM. Most of the compounds showed no significant toxicity against murine macrophages. Our initial investigation on the mechanism of action indicates that this series of compounds may exert their anti-parasitic effect, inducing cell membrane damage. The results in trypomastigotes showed that one derivative, PDAN 78, satisfactorily inhibited metabolic alteration at all concentrations. Moreover, we used molecular modeling to understand how tridimensional and structural aspects might influence the observed bioactivities. Finally, we also used in silico approaches to assess the potential pharmacokinetic and toxicological properties of the most active compounds. Our initial results indicate that this molecular scaffold might be a valuable prototype for novel and safe trypanocidal compounds.

Triazoles with inhibitory action on P2X7R impaired the acute inflammatory response in vivo and modulated the hemostatic balance in vitro and ex vivo.

OBJECTIVE: The present study aimed to investigate five triazole compounds as P2X7R inhibitors and evaluate their ability to reduce acute inflammation in vivo. MATERIAL: The synthetic compounds were labeled 5e, 8h, 9i, 11, and 12. TREATMENT: We administered 500 ng/kg triazole analogs in vivo, (1-10 µM) in vitro, and 1000 mg/kg for toxicological assays. METHODS: For this, we used in vitro experiments, such as platelet aggregation, in vivo experiments of paw edema and peritonitis in mice, and in silico experiments. RESULTS: The tested substances 5e, 8h, 9i, 11, and 12 produced a significant reduction in paw edema. Molecules 5e, 8h, 9i, 11, and 12 inhibited carrageenan-induced peritonitis. Substances 5e, 8h, 9i, 11, and 12 showed an anticoagulant effect, and 5e at a concentration of 10 µM acted as a procoagulant. All derivatives, except for 11, had pharmacokinetic, physicochemical, and toxicological properties suitable for substances that are candidates for new drugs. In addition, the ADMET risk assessment shows that derivatives 8h, 11, 5e, and 9i have high pharmacological potential. Finally, docking tests indicated that the derivatives have binding energies comparable to the reference antagonist with a competitive inhibition profile. CONCLUSIONS: Together, the results indicate that the molecules tested as antagonist drugs of P2X7R had anti-inflammatory action against the acute inflammatory response.

Synthesis, Biological Evaluation and Molecular Modeling Studies of Naphthoquinone Sulfonamides and Sulfonate Ester Derivatives as P2X7 Inhibitors.

ATP acts in the extracellular environment as an important signal, activating a family of receptors called purinergic receptors. In recent years, interest in the potential therapeutics of purinergic components, including agonists and antagonists of receptors, has increased. Currently, many observations have indicated that ATP acts as an important mediator of inflammatory responses and, when found in high concentrations in the extracellular space, is related to the activation of the P2X7 purinergic receptor. In this sense, the search for new inhibitors for this receptor has attracted a great deal of attention in recent years. Sulfonamide derivatives have been reported to be potent inhibitors of P2X receptors. In this study, ten naphthoquinone sulfonamide derivatives and five naphthoquinone sulfonate ester derivatives were tested for their inhibitory activity on the P2X7 receptor expressed in peritoneal macrophages. Some compounds showed promising results, displaying IC50 values lower than that of A740003. Molecular docking and dynamic studies also indicated that the active compounds bind to an allosteric site on P2X7R. The binding free energy indicates that sulfonamides have an affinity for the P2X7 receptor similar to A740003. Therefore, the compounds studied herein present potential P2X7R inhibition.

Molluscicidal and Cercaricidal Effects of Myrciaria floribunda Essential Oil Nanoemulsion.

Schistosomiasis is a tropical disease transmitted in an aqueous environment by cercariae from the Schistosoma genus. This disease affects 200 million people living in risk areas around the world. The control of schistosomiasis is realized by chemotherapy, wastewater sanitation, health education, and mollusk control using molluscicidal agents. This work evaluates the effects of a nanoemulsion containing essential oil from Myrciaria floribunda leaves as a molluscicidal and cercaricidal agent against Biomphalaria glabrata mollusks and Schistosoma mansoni cercariae. The Myrciaria floribunda essential oil from leaves showed nerolidol, ß-selinene, 1,8 cineol, and zonarene as major constituents. The formulation study suggested the F3 formulation as the most promising nanoemulsion with polysorbate 20 and sorbitan monooleate 80 (4:1) with 5% (w/w) essential oil as it showed a smaller droplet size of approximately 100 nm with a PDI lower than 0.3 and prominent bluish reflection. Furthermore, this nanoemulsion showed stability after 200 days under refrigeration. The Myrciaria floribunda nanoemulsion showed LC50 values of 48.11 µg/mL, 29.66 µg/mL, and 47.02 µg/mL in Biomphalaria glabrata embryos, juveniles, and adult mollusks, respectively, after 48 h and 83.88 µg/mL for Schistosoma mansoni cercariae after 2 h. In addition, a survival of 80% was observed in Danio rerio, and the in silico toxicity assay showed lower overall human toxicity potential to the major compounds in the essential oil compared to the reference molluscicide niclosamide. These results suggest that the nanoemulsion of Myrciaria floribunda leaves may be a promising alternative for schistosomiasis control.

Synthesis and biological evaluation of ß-lapachone and nor-ß-lapachone complexes with 2-hydroxypropyl-ß-cyclodextrin as trypanocidal agents.

We study ßLAP and its derivative nor-ß-Lapachone (NßL) complexes with 2-hydroxypropyl-ß-cyclodextrin to increase the solubility and bioavailability. The formation of true inclusion complexes between ßLAP or NßL in 2-HP-ß-CD in solid solution was characterization by FT-IR, DSC, powder X-ray was and was confirmed by one- and two-dimensional 1H NMR experiments. Additionally, the biological activities of ßLAP, NßL, ICßLAP, and ICNßL were investigated through trypanocidal assays with T. cruzi and cytotoxicity studies with mouse peritoneal macrophages. Originally, we tested these complexes against T. cruzi viability and observed higher biological activities and lower cytotoxicity when compared to ßLAP and NßL. Thus, the complexation of ßLAP and NßL with 2-HP-ß-CD increases the drug solubility, in addition vectorization was observed, increasing the biological activity against epimastigotes and trypomastigotes T. cruzi forms. Reduced the toxicity of the compounds against mammalian cells. In addition, the selectivity indices higher of the inclusion complexes comparing to substance free and those of benznidazole.

Synthesis of new N,S-acetal analogs derived from juglone with cytotoxic activity against Trypanossoma cruzi.

A series of 11 new N,S-acetal juglone derivatives were synthesized and evaluated against T. cruzi epimastigote forms. These compounds were obtained in good to moderate yields using a microwave irradiation protocol. Among all compounds, two N,S-acetal analogs, showed significant trypanocidal activity. Notably, one compound 11g exhibited selectivity index 10-fold higher than the reference drug benznidazole for epimastigote. The compound 11h was more effective for amastigote forms. Both prototypes exhibited S.I. higher than the benznidazole description. Thus, both compounds proving to be useful candidate molecules to further studies in infected animals.

P2X7 receptor inhibition by 2-amino-3-aryl-1,4-naphthoquinones.

Extracellular ATP activates purinergic receptors such as P2X7, cationic channels for Ca2+, K+, and Na+. There is robust evidence of the involvement of these receptors in the immune response, so P2X7 receptors (P2X7R) are considered a potential therapeutic target for the development of anti-inflammatory drugs. Although there are many studies of the anti-inflammatory properties of naphthoquinones, these molecules have not yet been explored as P2X7 antagonists. In previous work, our group prepared 3-substituted (halogen or aryl) 2-hydroxy-1,4-naphthoquinones and studied their action on P2X7R. In this paper, eight 2-amino-3-aryl-1,4-naphthoquinones were evaluated to identify the inhibitory activity on P2X7R and the toxicological profile. Three analogues (AD-4CN, AD-4Me, and AD-4F) exhibited reduced toxicity for mammalian cells with CC50 values higher than 500 µM. These three 3-substituted 2-amino-1,4-naphthoquinones inhibited murine P2X7R (mP2X7R) in vitro. However, the analogues AD-4CN and AD-4Me showed low selectivity index values. AD-4F inhibited both mP2X7R and human P2X7R (hP2X7R) with IC50 values of 0.123 and 0.93 µM, respectively. Additionally, this analogue exhibited higher potency than BBG at inhibiting the ATP-induced release of IL-1ß in vitro. Carrageenan-induced paw edema in vivo was reversed for AD-4F with an ID50 value of 11.51 ng/kg. Although AD-4F was less potent than previous 3-substituted (halogen or aryl) 2-hydroxy-1,4-naphthoquinones such as AN-04in vitro, this 3-substituted 2-amino-1,4-naphthoquinone revealed higher potency in vivo to reduce the edematogenic response. In silico analysis suggests that the binding site of the novel 2-amino-3-aryl-1,4-naphthoquinone derivatives, including all the tautomeric forms, is located in the pore area of the hP2X7R model. Based on these results, we considered AD-4F to be a satisfactory P2X7R inhibitor. AD-4F might be used as a scaffold structure to design a novel series of inhibitors with potential inhibitory activity on murine (mP2X7R) and human (hP2X7R) P2X7 receptors.

Arylboronic acids inhibit P2X7 receptor function and the acute inflammatory response.

The P2X7 receptor (P2X7R) is an ion channel which is activated by interactions with the extracellular ATP molecules. The molecular complex P2X7R/ATP induces conformational changes in the protein subunits, opening a pore in the ion channel macromolecular structure. Currently, the P2X7R has been studied as a potential therapeutic target of anti-inflammatory drugs. Based on this, a series of eight boronic acids (NO) analogs were evaluated on the biologic effect of this pharmacophoric group on the human and murine P2X7R. The boronic acids derivatives NO-01 and NO-12 inhibited in vitro human and murine P2X7R function. These analogs compounds showed effect better than compound BBG and similar to inhibitor A740003 for inhibiting dye uptake, in vitro IL-1ß release and ATP-induced paw edema in vivo. In both, in vitro and in vivo assays the compound NO-01 showed to be the hit compound in the present series of the arylboronic acids analogs. The molecular docking suggests that the NO derivatives bind into the upper body domain of the P2X7 pore and that the main intermolecular interaction with the two most active NO derivatives occur with the residues Phe 95, 103 and 293 by hydrophobic interactions and with Leu97, Gln98 and Ser101 by hydrogen bonds.. These results indicate that the boronic acid derivative NO-01 shows the lead compound characteristics to be used as a scaffold structure to the development of new P2X7R inhibitors with anti-inflammatory action.

Nanoemulsion containing essential oil from Xylopia ochrantha Mart. produces molluscicidal effects against different species of Biomphalaria (Schistosoma hosts).

BACKGROUND: This work describes a chemical study of the essential oil from leaves of Xylopia ochrantha, an endemic Annonaceae species from Brazil, and its activity against Biomphalaria species. Considering its poor solubility in aqueous medium, the essential oil was nanoemulsified to evaluate its action on controlling some mollusc species of genus Biomphalaria, snail hosts of Schistosoma mansoni that causes schistosomiasis, which mainly affects tropical and subtropical countries. OBJECTIVES: The main aims of this work were to analyse the chemical composition of essential oil from X. ochrantha, and to evaluate the effect of its nanoemulsion on molluscs of genus Biomphalaria and their oviposition. METHODS: Chemical analysis was performed by gas chromatography coupled to mass spectrometry. Nanoemulsions were prepared by a low energy method and characterised by particle size and polydispersity index. Biological assays evaluating the mortality of adult species of B. glabrata, B. straminea and B. tenagophila and their ovipositions upon contact with the most stable nanoemulsion during 24 and 48 h were performed. FINDINGS: Chemical analysis by mass spectrometry revealed the majority presence of bicyclogermacrene and germacrene D in the essential oil. The formulation with a hydrophilic-lipophilic balance (HLB) of 9.26 was the most suitable for the oil delivery system. This nanoemulsion caused the mortality in B. tenagophila, B. straminea and B. glabarata of different sizes at levels ranging from 50 to 100% in 48 h. Additionally, the formulation could inhibit the development of deposited eggs. CONCLUSION: Thus, these results suggest the use of nanoemulsified essential oil from X. ochrantha as a possible alternative in controlling some Biomphalaria species involved in the schistosomiasis cycle.

Purinergic receptors and neglected tropical diseases: why ignore purinergic signaling in the search for new molecular targets?

Purinergic receptors are widespread in the human organism and are involved in several physiological functions like neurotransmission, nociception, platelet aggregation, etc. In the immune system, they may regulate the expression and release of pro-inflammatory factors as well as the activation and death of several cell types. It is already described the participation of some purinergic receptors in the inflammation and pathological processes, such as a few neglected tropical diseases (NTDs) which affect more than 1 billion people in the world. Although the high social influence those diseases represent endemic countries, most of them do not have an efficient, safe or affordable drug treatment. In that way, this review aims to discuss the current literature involving purinergic receptor and immune response to NTDs pathogens, which may contribute in the search for new therapeutic possibilities.

Searching for new drugs for Chagas diseases: triazole analogs display high in vitro activity against Trypanosoma cruzi and low toxicity toward mammalian cells.

Chagas disease is one of the most relevant endemic diseases in Latin America caused by the flagellate protozoan Trypanosoma cruzi. Nifurtimox and benzonidazole are the drugs used in the treatment of this disease, but they commonly are toxic and present severe side effects. New effective molecules, without collateral effects, has promoted the investigation to develop new lead compounds with to advance for clinical trials. Previously, 3-nitro-1H-1,2,4-triazole-based amines and 1,2,3-triazoles demonstrated significant trypanocidal activity against T. cruzi. In this paper, we synthesized a new series of 92 examples of 1,2,3-triazoles. Six compounds exhibited antiparasitic activity, 14, 25, 27, 31 and 40, 43 and were effective against epimastigotes of two strains of T. cruzi (Y and Dm28-C) and 25, 27 and 31 exhibited trypanocidal activity similar to benzonidazole. Notably, the compound 25 compared to benzonidazole increase the toxicity against T. cruzi, with no apparent toxicity to the cell line of mice macrophages or primary mice peritoneal macrophages. As results, we calculated selectivity indexes up to 2000 to 25 and 31 in both T. cruzi strains. Derivative 14 caused a trypanostatic effect because it did not damage external epimastigote membrane. Triazoles 40 and 43 impaired parasites viability using a pathway not dependent on ROS production.

Plants of Brazilian restingas with tripanocide activity against Trypanosoma cruzi strains.

Chagas disease is caused by the Trypanosoma cruzi affecting millions of people, and widespread throughout Latin America. This disease exhibits a problematic chemotherapy. Benznidazole, which is the drug currently used as standard treatment, lamentably evokes several adverse reactions. Among other options, natural products have been tested to discover a novel therapeutic drug for this disease. A lot of plants from the Brazilian flora did not contain studies about their biological effects. Restinga de Jurubatiba from Brazil is a sandbank ecosystem poorly studied in relation to plant biological activity. Thus, three plant species from Restinga de Jurubatiba were tested against in vitro antiprotozoal activity. Among six extracts obtained from leaves and stem parts and 2 essential oils derived from leave parts, only 3 extracts inhibited epimastigote proliferation. Substances present in the extracts with activity were isolated (quercetin, myricetin, and ursolic acid), and evaluated in relation to antiprotozoal activity against epimastigote Y and Dm28 Trypanosoma cruzi strains. All isolated substances were effective to reduce protozoal proliferation. Essentially, quercetin and myricetin did not cause mammalian cell toxicity. In summary, myricetin and quercetin molecule can be used as a scaffold to develop new effective drugs against Chagas's disease.

P2X7 receptor as a novel drug delivery system to increase the entrance of hydrophilic drugs into cells during photodynamic therapy.

The second-generation photosensitizer methylene blue (MB) exhibits photochemical and photophysical properties suitable for photodynamic therapy (PDT)-based cancer treatment. However, the clinical application of MB is limited because of its high hydrophilicity, which hinders its penetration into tumor tissues. Therefore, new methods to improve the entry of MB into the cytoplasm of target cells are necessary. Because MB has a mass of 319 Da, transient pores on the plasma membrane, such as the pore induced by the P2X7 receptor (P2X7R) that allows the passage of molecules up to 900 Da, could be used. Using MTT viability assays, flow cytometry experiments, and fluorescence microscopy, we evaluated the toxicity and phototoxicity of MB and potentiation effects of ATP and MB on cell death processes in the J774 cell line (via a P2X7-associated pore). We observed that treatment with 5 µM MB for 15 min promoted the rate of entry of MB into the cytoplasm to 4.7 %. However, treatment with 5 µM MB and 1 mM ATP for the same amount of time increased this rate to 90.2 %. However, this effect was inhibited by pretreatment with a P2X7 antagonist. We used peritoneal macrophages and a cell line that does not express P2X7R as controls. These cells were more resistant to PDT with MB under the same experimental conditions. Taken together, these results suggest the use of the pore associated with P2X7R as a drug delivery system to increase the passage of hydrophilic drugs into cells that express this receptor, thus facilitating PDT.

A new insight into purinergic pharmacology: Three fungal species as natural P2X7R antagonists.

P2X7 is a purinergic receptor involved in important physiological functions and pathological processes, such as inflammation, neurodegeneration, and pain. Despite its relevance, there is no selective antagonist useful in the treatment of diseases related to this receptor. In this context, research for a selective, safe, and potent antagonist compound that can be used in clinical therapy has been growing. In this work, we evaluated the potential antagonistic activity of three fungal extracts, namely, Vishniacozyma victoriae, Metschnikowia australis, and Ascomycota sp., which were discovered in a high-throughput screening campaign to search for new antagonists for P2X7R from natural products. First, the IC50 values of these fungal extracts were determined in J774.G8 (murine macrophage cell line) and U937 (human monocyte cell line) cells through dye uptake assays. The IC50 values of V. victoriae were 2.6 and 0.92 µg/mL, M. australis has IC50 values of 3.8 and 1.5 µg/mL, and Ascomycota sp. showed values of 2.1 and 0.67 µg/mL in J774.G8 and U937 cells, respectively. These extracts also significantly inhibited propidium iodide and Lucifer yellow uptake via P2X7R pore, P2X7R currents in electrophysiology, IL-1ß release, and the production of oxide nitric and reactive oxygen species. The extracts did not cause cytotoxicity within a period of 24 h. The results showed the promising antagonistic activity of these extracts toward P2X7R, thereby indicating that they can be future candidates for phytomedicines with potential clinical applicability.

The Search for Drugs Derived from Natural Products for Toxoplasma gondii Infection Treatment in the Last 20 Years - A Systematic Review.

INTRODUCTION: Toxoplasmosis is a worldwide distributed zoonosis caused by Toxo-plasma gondii (T. gondii), an obligate intracellular protozoan. The infection in immunocompetent hosts usually progresses with mild or no symptoms. However, in immunocompromised individu-als, this disease can cause severe or fatal symptoms. METHOD: Sulfadiazine and pyrimethamine are two drugs used as standard therapies for human toxoplasmosis. Although they do not cause chronic infection, they may cause hematological tox-icity, hypersensitivity, intolerance, teratogenic effects, gastrointestinal disorders, and bone mar-row suppression. RESULT: The limited effect, significant toxicity, and emerging resistance to current drugs available to treat T. gondii infections require investigating other effective, nontoxic, and well-tolerated al-ternatives. Medicinal plants are, traditionally, the most promising sources used to treat infectious diseases. CONCLUSION: This review provides data on new therapeutic and prophylactic methods for T. gondii infection based on the use of extracts and/or compounds derived from natural products, which have been reported to be useful as alternative treatment options in the last 20 years.

A consensus segment in the M2 domain of the hP2X(7) receptor shows ion channel activity in planar lipid bilayers and in biological membranes.

The P2X(7) receptor (P2X(7)R) is an ATP-gated, cation-selective channel permeable to Na(+), K(+) and Ca(2+). This channel has also been associated with the opening of a non-selective pore that allows the flow of large organic ions. However, the biophysical properties of the P2X(7)R have yet to be characterized unequivocally. We investigated a region named ADSEG, which is conserved among all subtypes of P2X receptors (P2XRs). It is located in the M2 domain of hP2X(7)R, which aligns with the H5 signature sequence of potassium channels. We investigated the channel forming ability of ADSEG in artificial planar lipid bilayers and in biological membranes using the cell-attached patch-clamp techniques. ADSEG forms channels, which exhibit a preference for cations. They are voltage independent and show long-term stability in planar lipid bilayers as well as under patch-clamping conditions. The open probability of the ADSEG was similar to that of native P2X(7)R. The conserved part of the M2 domain of P2X(7)R forms ionic channels in planar lipid bilayers and in biological membranes. Its electrophysiological characteristics are similar to those of the whole receptor. Conserved and hydrophobic part of the M2 domain forms ion channels.

Physiological roles and potential therapeutic applications of the P2X7 receptor in inflammation and pain.

The P2X7 receptor (P2X7R) is a nonselective cation channel that is activated by extracellular ATP and triggers the secretion of several proinflammatory substances, such as IL-1ß, IL-18, TNF-α, and nitric oxide. Recently, several preclinical studies have demonstrated that this receptor participates in inflammation and pain mechanisms. Taken together, these results indicate that P2X7R is a promising pharmacological target, and compounds that modulate the function of this receptor show potential as new anti-inflammatory medicines. In this review, we discuss aspects of P2X7R pharmacology and the participation of this protein in inflammation and pain and provide an overview of some promising compounds that have been tested as antagonists of P2X7R, with clinical applicability.

Synthetic molecules as P2X7 receptor antagonists: A medicinal chemistry update focusing the therapy of inflammatory diseases.

Stimulation of the P2X7 receptor by extracellular adenosine 5'-triphosphate induces a series of responses in the organism, exceptionally protein cascades related to the proinflammatory process. This has made P2X7 a target for research on inflammatory diseases such as rheumatoid arthritis. Thus, the incessant search for new prototypes that aim to antagonize the action of P2X7 has been remarkable in recent decades, a factor that has already led to numerous clinical studies in humans. In this review, we present the key molecules developed over the years with potential inhibition of P2X7 and inflammation. In addition, an update with newly developed chemical classes with promising activity and results in clinical studies for human pathologies focusing on P2X7 inhibition.

Molluskicidal nanoemulsion of Neomitranthes obscura (DC.) N. Silveira for schistosomiasis control.

Schistosomiasis is caused by the parasite Schistosoma mansoni, which uses mollusks of the Biomphalaria genus as intermediate hosts. In 2020, approximately 241 million people worldwide underwent treatment for schistosomiasis. For this reason, the World Health Organization encourages research on alternative molluskicides based on plant species. The objective of this work was to investigate Neomitranthes obscura essential oil from leaf chemical composition and its essential oil nanoemulsion activity on intermediate hosts of schistosomiasis Biomphalaria glabrata control. The major chemical components of the Neomitranthes obscura essential oil were zonarene, seline-3,7(11)-diene, ß-selinene, and α-selinene. The nanoemulsion tested using 24-well plate methodology showed lethality and juvenile mollusks with LC90 values of 53.9 and 25.0 ppm after 48 h, respectively, and on their spawning with an LC90 of 66.2 ppm after 48 h. Additionally, the nanoemulsion exhibited an LC90 value against the infective form of the parasite Schistosoma mansoni of 11.5 ppm after 4 h. This pharmaceutical formulation acted inhibiting the acetylcholinesterase activity and was not toxic for Mellanoides sp. This result suggests the use of this nanoformulation as a promising alternative in the control of Biomphalaria glabrata and the transmission of schistosomiasis.