Potentiating-antibiotic activity and absorption, distribution, metabolism, excretion and toxicity properties (ADMET) analysis of synthetic thiadiazines against multi-drug resistant (MDR) strains.

BACKGROUND: Thiadiazines are heterocyclic compounds that contain two nitrogen atoms and one sulfur atom in their structure. These synthetic molecules have several relevant pharmacological activities, such as antifungal, antibacterial, and antiparasitic. OBJECTIVES: The present study aimed to evaluate the possible in vitro and in silico interactions of compounds derived from thiadiazines. METHODS: The compounds were initially synthesized, purified, and confirmed through HPLC methodology. Multi-drug resistant bacterial strains of Staphylococcus aureus 10 and Pseudomonas aeruginosa 24 were used to evaluate the direct and modifying antibiotic activity of thiadiazine derivatives. ADMET assays (absorption, distribution, metabolism, excretion, and toxicity) were conducted, which evaluated the influence of the compounds against thousands of macromolecules considered as bioactive targets. RESULTS: There were modifications in the chemical synthesis in carbon 4 or 3 in one of the aromatic rings of the structure where different ions were added, ensuring a variability of products. It was possible to observe results that indicate the possibility of these compounds acting through the cyclooxygenase 2 mechanism, which, in addition to being involved in inflammatory responses, also acts by helping sodium reabsorption. The amine group present in thiadiazine analogs confers hydrophilic characteristics to the substances, but this primary characteristic has been altered due to alterations and insertions of other ligands. The characteristics of the analogs generally allow easy intestinal absorption, reduce possible hepatic toxic effects, and enable possible neurological and anti-inflammatory action. The antibacterial activity tests showed a slight direct action, mainly of the IJ23 analog. Some compounds were able to modify the action of the antibiotics gentamicin and norfloxacin against multi-drug resistant strains, indicating a possible synergistic action. CONCLUSIONS: Among all the results obtained in the study, the relevance of thiadiazine analogs as possible coadjuvant drugs in the antibacterial, anti-inflammatory, and neurological action with low toxicity is clear. Need for further studies to verify these effects in living organisms is not ruled out.

ACW-02 an Acridine Triazolidine Derivative Presents Antileishmanial Activity Mediated by DNA Interaction and Immunomodulation.

The present study proposed the synthesis of a novel acridine derivative not yet described in the literature, chemical characterization by NMR, MS, and IR, followed by investigations of its antileishmanial potential. In vitro assays were performed to assess its antileishmanial activity against L. amazonensis strains and cytotoxicity against macrophages through MTT assay and annexin V-FITC/PI, and the ability to perform an immunomodulatory action using CBA. To investigate possible molecular targets, its interaction with DNA in vitro and in silico targets were evaluated. As results, the compound showed good antileishmanial activity, with IC50 of 6.57 (amastigotes) and 94.97 (promastigotes) µg mL-1, associated with non-cytotoxicity to macrophages (CC50 > 256.00 µg mL-1). When assessed by flow cytometry, 99.8% of macrophages remained viable. The compound induced an antileishmanial effect in infected macrophages and altered TNF-α, IL-10 and IL-6 expression, suggesting a slight immunomodulatory activity. DNA assay showed an interaction with the minor grooves due to the hyperchromic effect of 47.53% and Kb 1.17 × 106 M-1, and was sustained by docking studies. Molecular dynamics simulations and MM-PBSA calculations propose cysteine protease B as a possible target. Therefore, this study demonstrates that the new compound is a promising molecule and contributes as a model for future works.

Genotoxicity and Anticancer Effects of the Aminothiophene Derivatives SB-44, SB- 83, and SB-200 in Cancer Cells.

INTRODUCTION: Thiophene derivatives have been widely studied as promising options for the treatment of solid tumors. Previous studies have shown that thiophene derivatives have antileishmanial activity and cytotoxic activity against breast, colon, and ovarian cancer cells. METHODS: In our study, we evaluated the anticancer activities of three aminothiophene derivatives: SB-44, SB-83, and SB-200, in prostate and cervical adenocarcinoma cells. Several in vitro methods were performed, including cytotoxicity, clonogenic migration, mutagenic, and cleaved Poly (ADP-ribose) polymerase (PARP) assays and annexin V staining. RESULTS: Significant cytotoxicity was observed in cell lines with IC50 values less than 35 µM (15.38-34.04 µM). All aminothiophene derivatives significantly reduced clone formation but had no effect on cell motility. SB-83 and SB-44 induced a significant increase in the percentage of cells in the sub-G1 phase, while SB-200 derivatives significantly decreased the percentage of S/G2/M as well as induced apoptosis, with an increase of cleaved PARP. SBs compounds also showed significant mutagenic potential. Beyond that, in silico analyses revealed that all three thiophene derivatives fulfilled the criteria for oral druggability, which underscores the potential of using them in anticancer therapies. CONCLUSION: Our findings show that the thiophene nucleus may be used to treat solid tumors, including prostate cancer and cervical adenocarcinoma.

Computer-Assisted Design of Thiophene-Indole Hybrids as Leishmanial Agents.

BACKGROUND: Chemoinformatics has several applications in the field of drug design, helping to identify new compounds against a range of ailments. Among these are Leishmaniasis, effective treatments for which are currently limited. OBJECTIVE: To construct new indole 2-aminothiophene molecules using computational tools and to test their effectiveness against Leishmania amazonensis (sp.). METHODS: Based on the chemical structure of thiophene-indol hybrids, we built regression models and performed molecular docking, and used these data as bases for design of 92 new molecules with predicted pIC50 and molecular docking. Among these, six compounds were selected for the synthesis and to perform biological assays (leishmanicidal activity and cytotoxicity). RESULTS: The prediction models and docking allowed inference of characteristics that could have positive influences on the leishmanicidal activity of the planned compounds. Six compounds were synthesized, one-third of which showed promising antileishmanial activities, with IC50 ranging from 2.16 and 2.97 µM (against promastigote forms) and 0.9 and 1.71 µM (against amastigote forms), with selectivity indexes (SI) of 52 and 75. CONCLUSION: These results demonstrate the ability of Quantitative Structure-Activity Relationship (QSAR)-based rational drug design to predict molecules with promising leishmanicidal potential, and confirming the potential of thiophene-indole hybrids as potential new leishmanial agents.

Evaluation of anti-inflammatory activity and molecular docking study of new aza-bicyclic isoxazoline acylhydrazone derivatives.

The aim of this study was to investigate the anti-inflammatory effects of two new isoxazoline-acylhydrazone derivatives: N'-(4-methoxybenzylidene)-6-(4-nitro-benzoyl)-3a,5,6,6a-tetrahydro-4H-pyrrolo[3,2-d]isoxazole-3-carbohydrazide (R-123) and N'-(4-chlorobenzylidene)-6-(4-chlorobenzoyl)-3a,5,6,6a-tetrahydro-4H-pyrrolo[3,2-d]isoxazole-3-carbohydrazide (R-99). An air pouch induced by carrageenan was used for screening the best dose of R-99 and R-123. Using this mouse model, leukocyte migration and cytokine levels (TNF-α and IL-1ß) were determined. Paw edema induced by several phlogistic agents and vascular permeability induced by acetic acid were employed to investigate the mechanism of action of the isoxazoline-acylhydrazone derivatives. A docking study was performed with the human histamine H1 receptor to investigate potential antihistaminic activity. Treatment with the compounds reduced leukocyte migration in the air pouch at all doses tested. TNF-α and IL-1ß levels were similarly reduced by the two compounds. Vasoactive amines were inhibited in models of paw edema induced by several agents and vascular permeability induced by acetic acid. The docking study suggests that R-99 and R-123 may be inhibitors of the histamine H1 receptor. In conclusion, the results indicate that R-99 and R-123 exhibit promising anti-inflammatory activity related to their ability to inhibit TNF-α, IL-1ß, and vasoactive amine production, as well as reduce leukocyte migration and inhibit mast cell degranulation.

A new diethylcarbamazine formulation (NANO-DEC) as a therapeutic tool for hepatic fibrosis.

The aim of the present study was to assess if the uninterrupted and prolonged administration of nanoparticles containing diethylcarbamazine (NANO-DEC) would cause liver, kidney and heart toxicity and then analyze for the first time its action in model of liver fibrosis. Thus, NANO-DEC was administered in C57BL/6 mice daily for 48 days, and at the end the blood was collected for biochemical analyzes. In the long-term administration assay, the evaluation of serological parameters (CK-MB, creatinine, ALT, AST and urea) allowed the conclusion that NANO-DEC prolonged administration did not cause hepatic, renal and cardiac damage. For fibrosis assays, C57BL/6 mice were divided into six groups: 1) control (Cont); 2) carbon tetrachloride (CCl4); 3) CCl4 + DEC 25 mg/kg; 4) CCl4 + DEC 50 mg/kg; 5) CCl4 + NANO-DEC 5 mg/kg and 6) CCl4 + NANO-DEC 12.5 mg/kg. Carbon tetrachloride induced hepatic fibrosis observed through increased inflammatory (TNF-α, IL-1ß, COX-2, NO and iNOS) and fibrotic markers (TGF-ß and TIMP-1), changes in the hepatic morphology, high presence of collagen fibers and elevated serum levels of AST, ALT and ALP. Treatment with NANO-DEC exhibited a superior anti-inflammatory and anti-fibrotic effects compared to the DEC traditional formulation, restoring liver morphology, reducing the content of collagen fibers and serological parameters, besides decreasing the expression of inflammatory and fibrotic markers. The present formulation of nanoencapsulated DEC is a well tolerated anti-inflammatory and anti-fibrotic drug and therefore could be a potential therapeutic tool for the treatment of chronic liver disorders.

Characterization and evaluation of nanoencapsulated diethylcarbamazine in model of acute hepatic inflammation.

Previous studies from our laboratory have demonstrated that Diethylcarbamazine (DEC) is a potent anti-inflammatory drug. The aim of the present study was to characterize the nanoencapsulation of DEC and to evaluate its effectiveness in a model of inflammation for the first time. C57BL/6 mice were divided into six groups: 1) Control; 2) Carbon tetrachloride (CCl4); 3) DEC 25mg/kg+CCl4; 4) DEC 50mg/kg+CCl4; 5) DEC-NANO 05mg/kg+CCl4 and 6) DEC-NANO 12.5mg/kg+CCl4. Liver fragments were stained with hematoxylin-eosin, and processed for Western blot, ELISA and immunohistochemistry. Serum was also collected for biochemical measurements. Carbon tetrachloride induced hepatic injury, observed through increased inflammatory markers (TNF-α, IL-1ß, PGE2, COX-2 and iNOS), changes in liver morphology, and increased serum levels of total cholesterol, triglycerides, TGO and TGP, LDL, as well as reduced HDL levels. Nanoparticles containing DEC were characterized by diameter, polydispersity index and zeta potential. Treatment with 12.5 nanoencapsulated DEC exhibited a superior anti-inflammatory action to the DEC traditional dose (50mg/kg) used in murine assays, restoring liver morphology, improving serological parameters and reducing the expression of inflammatory markers. The present formulation of nanoencapsulated DEC is therefore a potential therapeutic tool for the treatment of inflammatory hepatic disorders, permitting the use of smaller doses and reducing treatment time, while maintaining high efficacy.

Antifungal activity of topical microemulsion containing a thiophene derivative.

Fungal infections have become a major problem of worldwide concern. Yeasts belonging to the Candida genus and the pathogenic fungus Cryptococcus neoformans are responsible for different clinical manifestations, especially in immunocompromised patients. Antifungal therapies are currently based on a few chemotherapeutic agents that have problems related to effectiveness and resistance profiles. Microemulsions are isotropic, thermodynamically stable transparent systems of oil, water and surfactant that can improve the solubilization of lipophilic drugs. Taking into account the need for more effective and less toxic drugs along with the potential of thiophene derivatives as inhibitors of pathogenic fungi growth, this study aimed to evaluate the antifungal activity of a thiophene derivative (5CN05) embedded in a microemulsion (ME). The minimum inhibitory concentration (MIC) was determined using the microdilution method using amphotericin B as a control. The formulations tested (ME- blank and ME-5CN05) showed physico-chemical properties that would allow their use by the topical route. 5CN05 as such exhibited moderate or weak antifungal activity against Candida species (MIC = 270-540 µg . mL(-1)) and good activity against C. neoformans (MIC = 17 µg . mL(-1)). Candida species were susceptible to ME-5CN05 (70-140 µg . mL(-1)), but C. neoformans was much more, presenting a MIC value of 2.2 µg . mL(-1). The results of this work proved promising for the pharmaceutical industry, because they suggest an alternative therapy against C. neoformans.