https://repositorio.ufu.br/handle/123456789/19178 2026-08-29T04:52:35Z 2026-08-29T04:52:35Z https://repositorio.ufu.br/handle/123456789/49924 2026-08-28T06:20:14Z 2026-08-06T00:00:00Z

Title: Análise de novos compostos orgânicos sintéticos em formas promastigotas de Leishmania (Leishmania) amazonensis: potencial citotóxico e interações in silico Abstract: Leishmaniasis is a neglected tropical disease caused by protozoa of the genus Leishmania. This disease has two main forms: visceral leishmaniasis and cutaneous leishmaniasis. In Brazil, one of the main species responsible for the latter is Leishmania (L.) amazonensis. Its treatment involves drugs that are highly toxic to the human body, and there are reports of strains resistant to standard treatments, making it necessary to develop new leishmanicidal alternatives. This study aimed to investigate the cytotoxic potential of three synthetic compounds against promastigote forms of L. (L.) amazonensis and in murine macrophages, and to conduct in silico investigations to identify a potential protein target for these compounds. The results showed high cytotoxicity and selectivity of the tested compounds, with compound RMS25 standing out, exhibiting an IC50 of 1.194 μM and a selectivity of 20.335. The application of docking and molecular dynamics techniques to the selected protein, Glycogen Synthase Kinase 3 from L. (L.) amazonensis, indicated favorable results for compound RMS25, such as high complex stability, consistent protein-ligand interactions, and low binding energy, comparable to a reference inhibitor.

2026-08-06T00:00:00Z https://repositorio.ufu.br/handle/123456789/49888 2026-08-28T06:20:23Z 2026-08-07T00:00:00Z

Title: Efeitos da exposição a pesticidas sobre a citotoxicidade e o potencial de membrana mitocondrial em células hepáticas humanas Abstract: The intensive use of pesticides in modern agriculture has increased in recent decades, driven by the growing demand for food and the need to control pests and diseases in crops of great economic importance. However, human exposure to these compounds, especially through residues present in food and the environment, has raised concerns due to their potential toxic effects. The liver is one of the main target organs of toxicity caused by agricultural pesticides, as it plays a central role in the biotransformation and detoxification of these compounds. In this context, this study aimed to evaluate the effects of the fungicides dimethomorph (DIM) and fenpropimorph (FEN) on cell viability, metabolic activity, and mitochondrial membrane potential in human hepatic cells lines HepG2 and LX-2. The cells were treated for 24 hours with different concentrations of the fungicides and subjected to Sulforhodamine B (SRB), Alamar Blue and tetramethylrhodamine ethyl ester (TMRE) assays. After 24 hours of exposure, DIM at 300 µM significantly reduced cell viability and metabolic activity in both HepG2 and LX-2 cells, whereas FEN reduced LX-2 cell viability at 1 µM. Alterations in mitochondrial membrane potential were also observed, with decreased TMRE fluorescence in HepG2 cells exposed to DIM and FEN and increased TMRE fluorescence in LX-2 cells, indicating concentration- and cell line-dependent mitochondrial responses. These findings contribute to the understanding of the cellular mechanisms associated with the toxicity of these fungicides and reinforce the importance of in vitro studies to support future risk assessments related to human exposure to pesticides.

2026-08-07T00:00:00Z https://repositorio.ufu.br/handle/123456789/49857 2026-08-27T06:21:29Z 2026-03-30T00:00:00Z

Title: Investigação in vitro dos efeitos do látex de jatropha multifida em fibroblasto humano HFF-1 e a modulação desses efeitos via síntese verde de nanopartículas de prata Abstract: Skin diseases represent a significant public health problem, with particular concern for fibrosis, chronic wounds, or wounds that are difficult to heal. Given the limitations of current treatments, the search for new therapeutic alternatives has intensified, especially those involving natural compounds. The species Jatropha multifida has traditional use in the treatment of skin lesions, making it a potential source of bioactive compounds. Thus, this study aimed to evaluate the effects of the crude extract of the plant’s latex and of silver nanoparticles (AgNPs) synthesized via a green method on human fibroblast cells. The results showed that both the extract and the AgNPs interfere with cell viability, with up to an 80% reduction observed at extract concentrations above 375 µg/mL and at AgNP concentrations above 187.50 µg/mL. Furthermore, the evaluation of cell migration at three concentrations of the extract and AgNPs (23.44; 46.88; and 93.75 µg/mL) revealed an anti-migratory effect at all concentrations of the extract, while for AgNPs, this effect was observed only at concentrations of 46.88 and 93.75 µg/mL. Therefore, the data indicate that both the extract and the nanomaterial possess relevant biological activity, contributing to studies focused on cellular regeneration—either by controlling regeneration through anti-migratory properties or by replacing the extract with nanoparticles at less harmful concentrations.

2026-03-30T00:00:00Z https://repositorio.ufu.br/handle/123456789/49832 2026-08-26T06:18:53Z 2026-06-22T00:00:00Z

Title: Avaliação in silico do potencial de intercalação de DNA para aplicação em biossensores por meio de docking molecular Abstract: The DNA structure has an intrinsic conformational flexibility that is fundamental to understanding its organization and biological functions. Among the interactions highlighting this characteristic, intercalation stands out as a non-covalent mechanism where generally planar and aromatic molecules insert themselves between adjacent base pairs of the double helix. This process induces significant structural modifications, such as unwinding and elongation of the strand, which may interfere with vital cellular processes like replication and transcription. Given the biological and toxicological relevance of these interactions, evaluating the intercalating potential is crucial for understanding mechanisms of action, ensuring pharmaceutical safety, and developing biosensors. In this scenario, the use of in silico methods, such as molecular docking, allows for the three-dimensional modeling and quantification of the stability of these interactions, aiding in the prediction of the efficacy and genotoxicity of new compounds of biotechnological interest. The selection of molecules with intercalation capacity was performed through a screening of the NuBBE and PubChem databases, using a structure similar to the ethidium bromide biosensor as a research model. The study employed the Autodock Vina software for directed docking and blind docking against the DNA receptor (PDB 2ROU), validating the energetic preference for the identified binding sites. Furthermore, toxicity analyses for Ames mutagenicity and skin sensitization were conducted via the pkCSM platform, in addition to the visualization of 2D intermolecular interactions. The results allowed for the ranking of 17 compounds with affinities superior to the ethidium bromide control, with molecule 14771754 being a highlight. This compound exhibited favorable binding energy, a consistent binding mode, and an absence of mutagenicity, distinguishing itself from other candidates that, despite higher affinity, showed mutagenic potential.

2026-06-22T00:00:00Z