Effects of (1E,4E)-2-Methyl-1,5-bis(4-nitrophenyl)penta-1,4-dien-3-one on Trypanosoma cruzi and Its Combinational Effect with Benznidazole, Ketoconazole, or Fluconazole

Chitosan-dibenzylideneacetone based Schiff base: Evaluation of antimicrobial activity and in-vitro cytotoxicity on MCF-7 and L-132

This study holds significant importance as it explores the synthesis and characterization of two chitosan dibenzylideneacetone Schiff bases. Various analytical techniques, such as UV-visible spectroscopy, FTIR, XRD, TGA, DSC, SEM, and elemental analysis, were employed to thoroughly examine these derivatives. The antimicrobial activity of the chitosan derivatives was evaluated against a range of bacterial and fungal strains, while cytotoxicity tests were conducted on MCF-7, L-132, and VERO cell lines. In the antimicrobial tests, the chitosan derivatives exhibited remarkable antibacterial properties against S. aureus, E. coli, and Pseudomonas aeruginosa, as well as potent antifungal properties against Candida albicans and Aspergillus fumigatus. The cytotoxicity assessment revealed that the dibenzylideneacetone chitosan Schiff base (CHDBA) showed significant effectiveness against the L-132 cell line, surpassing the efficacy of doxorubicin by 2.44 times. Moreover, it exhibited substantial activity against the L-132 and MCF-7 cell lines, with IC50 values of 55.29 μg/mL and 185.8 μg/mL, respectively. Notably, none of the chitosan derivatives demonstrated cytotoxicity towards the normal cell line, indicating their non-toxic nature and safe usability. Based on these findings, it is evident that CHDBA holds promise for further development as a potential treatment option for breast cancer and lung cancer.

Synthetic dibenzylideneketones as promising anti-herpes simplex virus type 1 agents

New antiviral agents for the treatment of herpes simplex virus type 1 (HSV-1) infection, which causes a highly prevalent and incurable disease, are needed. Here, we report for the first time the in vitro anti-HSV-1 activity of two dibenzylideneketone compounds: DBK1 and DBK2. DBK1 demonstrated virucidal activity, and high-resolution scanning electron microscopy showed that it caused morphological changes in the HSV-1 envelope. DBK2 was able to reduce HSV-1 plaque size in vitro. The DBKs are promising anti-HSV-1 candidates, as they exhibit low toxicity and exert an antiviral effect by acting at the early stages of HSV-1-host cell interaction.

Structure-activity relationship of dibenzylideneacetone analogs against the neglected disease pathogen, Trypanosoma brucei

Trypanosoma brucei is a protozoan parasite that causes Human African Trypanosomiasis (HAT), a neglected tropical disease (NTD) that is endemic in 36 countries in sub-Saharan Africa. Only a handful drugs are available for treatment, and these have limitations, including toxicity and drug resistance. Using the natural product, curcumin, as a starting point, several curcuminoids and related analogs were evaluated against bloodstream forms of T. b. brucei. A particular subset of dibenzylideneacetone (DBA) compounds exhibited potent in vitro antitrypanosomal activity with sub-micromolar EC₅₀ values. A structure-activity relationship study including 26 DBA analogs was initiated, and several compounds exhibited EC₅₀ values as low as 200 nM. Cytotoxicity counter screens in HEK293 cells identified several compounds having selectivity indices above 10. These data suggest that DBAs offer starting points for a new small molecule therapy of HAT.

Dibenzylideneacetone Induces Apoptosis in Cervical Cancer Cells through Ros-Mediated Mitochondrial Damage

Cervical cancer is a health problem among women worldwide. Considering the limitations of prevention and antineoplastic chemotherapy against cervical cancer, research is needed to discover new, more effective, and safe antitumor agents. In the present study, we investigated the in vitro cytotoxicity of a new synthetic dibenzylideneacetone derived from 1,5-diaryl-3-oxo-1,4-pentadienyl (A3K2A3) against cervical cancer cells immortalized by HPV 16 (SiHa), and 18 (HeLa) by MTT assay. Furthermore, we performed spectrofluorimetry, flow cytometry, and Western blot analyzes to explore the inhibitory mechanism of A3K2A3 in cervical cancer cells. A3K2A3 showed cytotoxic activity against both cell lines. Mitochondrial depolarization and reduction in intracellular ATP levels were observed, which may be dependent on the redox imbalance between increased ROS and reduced levels of the antioxidant defense. In addition, damage to the cell membrane and DNA, and effective blocking of cell division in the G2/M phase were detected, which possibly led to the induction of apoptosis. This result was further confirmed by the upregulation of apoptosis-related proteins Bax, cytochrome C, and caspases 9 and 3. Our results provided the first evidence that A3K2A3 contributes to the suppression of cervical cancer in vitro, showing promise as a possible alternative for the treatment of this cancer.

Chagas Disease Chemotherapy: What Do We Know So Far?

Chagas disease is a Neglected Tropical Disease (NTD), and although endemic in Latin America, affects around 6-7 million people infected worldwide. The treatment of Chagas disease is based on benznidazole and nifurtimox, which are the only available drugs. However, they are not effective during the chronic phase and cause several side effects. Furthermore, BZ promotes cure in 80% of the patients in the acute phase, but the cure rate drops to 20% in adults in the chronic phase of the disease. In this review, we present several studies published in the last six years, which describes the antiparasitic potential of distinct drugs, from the synthesis of new compounds aiming to target the parasite, as well as the repositioning and the combination of drugs. We highlight several compounds for having shown results that are equivalent or superior to BZ, which means that they should be further studied, either in vitro or in vivo. Furthermore, we stand out the differences in the effects of BZ on the same strain of T. cruzi, which might be related to methodological differences such as parasite and cell ratios, host cell type and the time of adding the drug. In addition, we discuss the wide variety of strains and also the cell types used as a host cell, which makes it difficult to compare the trypanocidal effect of the compounds.

Substituent effects on the stability, physicochemical properties and chemical reactivity of nitroimidazole derivatives with potential antiparasitic effect: a computational study

Neglected tropical diseases caused by parasitic pathogens have caused an increase in research interest in drug discovery.