The treatment of Chagas disease (CD), a neglected parasitic condition caused by Trypanosoma cruzi, is still based on only two drugs, nifurtimox (Nif) and benznidazole (Bz), both of which have limited ...efficacy in the late chronic phase and induce severe side effects. This scenario justifies the continuous search for alternative drugs, and in this context, the natural naphthoquinone β-lapachone (β-Lap) and its derivatives have demonstrated important trypanocidal activities. Unfortunately, the decrease in trypanocidal activity in the blood, high toxicity to mammalian cells and low water solubility of β-Lap limit its systemic administration and, consequently, clinical applications. For this reason, carriers as drug delivery systems can strategically maximize the therapeutic effects of this drug, overcoming the above mentioned restrictions. Accordingly, the aim of this study is to investigate the in vitro anti-T. cruzi effects of β-Lap encapsulated in2-hydroxypropyl-β-cyclodextrin (2HP-β-CD) and its potential toxicity to mammalian cells.
Thirty four halogen and selenium-containing quinones, synthesized by rhodium-catalyzed C-H bond activation and palladium-catalyzed cross-coupling reactions, were evaluated against bloodstream ...trypomastigotes of T. cruzi. We have identified fifteen compounds with IC50/24 h values of less than 2 μM. Electrochemical studies on A-ring functionalized naphthoquinones were also performed aiming to correlate redox properties with trypanocidal activity. For instance, (E)-5-styryl-1,4-naphthoquinone 59 and 5,8-diiodo-1,4-naphthoquinone 3, which are around fifty fold more active than the standard drug benznidazole, are potential derivatives for further investigation. These compounds represent powerful new agents useful in Chagas disease therapy.
Functionalized quinones were designed and synthesized by rhodium-catalyzed C-H bond activation and evaluated against Trypanosoma cruzi showing, in some cases, IC50 values below 0.2 μM. Display omitted
•Iodinated quinones were prepared with potent trypanocidal activity.•Rh-catalyzed reactions were used to prepare A-ring functionalized quinones.•Electrochemical aspects were also studied.
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•Planning of new Benzimidazole N-acylhydrazones with antitrypanosomal activity.•Biological evaluation of the compounds against T. cruzi strains (Y and Tulahuen)•Biological evaluation ...of the compounds against L. amazonensis and L. infantum.
In this study, we present the design, synthesis, and cytotoxic evaluation of a series of benzimidazole N-acylhydrazones against strains of T. cruzi (Y and Tulahuen) and Leishmania species (L. amazonensis and L. infantum). Compound (E)-N’-((5-Nitrofuran-2-yl)methylene)-1H-benzodimidazole-2-carbohydrazide demonstrated significant activity against both trypomastigote and amastigote forms (Tulahuen strain), with an IC50/120 h of 0.033 μM and a selectivity index (SI) of 7680. This represents a potency 46 times greater than that of benznidazole (IC50/120 h = 1.520 μM, SI = 1390). Another compound (E)-N’-(2-Hydroxybenzylidene)-1H-benzodimidazole-2-carbohydrazide showed promising activity against both trypomastigote and amastigote forms (Tulahuen strain), with an IC50/120 h of 3.600 μM and an SI of 14.70. However, its efficacy against L. infantum and L. amazonensis was comparatively lower. These findings provide valuable insights for the development of more effective treatments against Trypanosoma cruzi.
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•New N-aminobenzyl or N-arylhydrazone 1,3,4-thiadiazole derivatives were synthesized.•Target compounds were designed as analogues of CYP51 inhibitors.•1,3,4-Thiadiazoles showed ...trypanocidal action in trypomastigote forms of T. cruzi.•Compound 11a produced phenotypic changes similar to those caused by posaconazole.•Hydrochloride 11a can be considered as a good trypanocidal drug candidate.
Herein, we present the design, synthesis and trypanocidal evaluation of sixteen new 1,3,4-thiadiazole derivatives from N-aminobenzyl or N-arylhydrazone series. All derivatives were assayed against the trypomastigote form of Trypanosoma cruzi, showing IC50 values ranging from 3 to 226 μM, and a better trypanocidal profile was demonstrated for the 1,3,4-thiadiazole-N-arylhydrazones (3a-g). In this series, the 2-pyridinyl fragment bound to the imine subunit of the hydrazine moiety presented pharmacophoric behavior for trypanocidal activity. Compounds 2a, 11a and 3e presented remarkable activity and excellent selectivity indexes. Compound 2a was also active against the intracellular amastigote form of T. cruzi. Moreover, its corresponding hydrochloride, compound 11a, showed the most promising profile, producing phenotypic changes similar to those caused by posaconazole, a well-known inhibitor of sterol biosynthesis. Thus, 1,3,4-thiadiazole derivative 11a could be considered a good prototype for the development of new drug candidates for Chagas disease therapy.
Ortho
-Quinones represent a special class of redox active compounds associated with a spectrum of pronounced biological activities, including selective cytotoxicity and antimicrobial actions. The ...modification of the quinone ring by simple nitrogen and sulphur substitutions leads to several new classes of compounds with their own, distinct redox behaviour and equally distinct activities against cancer cell lines and
Trypanosoma cruzi
. Some of the compounds investigated show activity against
T. cruzi
at concentrations of 24.3 and 65.6 μM with a selectivity index of around 1. These results demonstrate that simple chemical modifications on the
ortho
-quinone ring system, in particular, by heteroatoms such as nitrogen and sulphur, transform these simple redox molecules into powerful cytotoxic agents with considerable "potential", not only in synthesis and electrochemistry, but also, in a broader sense, in health sciences.
New quinoidal compounds were prepared and evaluated against
T. cruzi
and cancer cell lines for the identification of new bioactive agents.
Approximately, 5-7 million people are infected with T. cruzi in the world, and approximately 10,000 people per year die of complications linked to this disease.
This work describes the construction ...of a new family of hidrazonoyl substituted derivatives, structurally designed exploring the molecular hybridization between megazol and nitrofurazone.
The compounds were evaluated for their in vitro activity against bloodstream trypomastigotes of Trypanosoma cruzi, etiological agent of Chagas disease, and for their potential toxicity to mammalian cells.
Among these hydrazonoyl derivatives, we identified the derivative (4) that showed trypanocidal activity (IC50/24 h = 15.0 µM) similar to Bz, the standard drug, and low toxicity to mammalian cells, reaching an SI value of 18.7.
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•β-lapachone-derived naphthoimidazolium N4 is very active on all T. cruzi stages.•Complexes II-III inhibition and mitochondrial ROS production was showed after 2 h.•Mitochondrial ...swelling and some physiology alterations were showed at 24 h.•Trypanothione reductase activity is time-dependent increased.•N4 interacts with succinate dehydrogenase and dihydroorotate dehydrogenase.
Trypanosoma cruzi is a protozoan parasite that causes Chagas disease, a neglected tropical disease that is endemic in Latin America and spreading worldwide due to globalization. The current treatments are based on benznidazole and nifurtimox; however, these drugs have important limitations and limited efficacy during the chronic phase, reinforcing the necessity of an alternative chemotherapy. For the last 30 years, our group has been evaluating the biological activity of naphthoquinones and derivatives on T. cruzi, and of the compounds tested, N1, N2 and N3 were found to be the most active in vitro. Here, we show the synthesis of a novel β-lapachone-derived naphthoimidazolium named N4 and assess its activity on T. cruzi stages and the mechanism of action. The new compound was very active on all parasite stages (IC50/24 h in the range of 0.8–7.9 μM) and had a selectivity index of 5.4. Mechanistic analyses reveal that mitochondrial ROS production begins after short treatment starts and primarily affects the activity of complexes II-III. After 24 h treatment, a partial restoration of mitochondrial physiology (normal complexes II-III and IV activities and controlled H2O2 release) was observed; however, an extensive injury in its morphology was still detected. During treatment with N4, we also observed that trypanothione reductase activity increased in a time-dependent manner and concomitant with increased oxidative stress. Molecular docking calculations indicated the ubiquinone binding site of succinate dehydrogenase as an important interaction point with N4, as with the FMN binding site of dihydroorotate dehydrogenase. The results presented here may be a good starting point for the development of alternative treatments for Chagas disease and for understanding the mechanism of naphthoimidazoles in T. cruzi.
Chagas disease (CD), caused by the protozoan
, is a neglected tropical disease and a health problem in Latin America. Etiological treatment has limited effectiveness in chronic CD; thus, new ...therapeutic strategies are required. The practice of physical exercises has been widely advocated to improve the quality of life of CD patients. The most frequent clinical CD manifestation is the chronic indeterminate form (CIF), and the effect of physical exercises on disease progression remains unknown. Here, in a CIF model, we aimed to evaluate the effect of physical exercises on cardiac histological, parasitological, mitochondrial, and oxidative metabolism, electro and echocardiographic profiles, and immunological features. To establish a CIF model, BALB/c and C57BL/6 mice were infected with 100 and 500 trypomastigotes of the Y
strain. At 120 days postinfection (dpi), all mouse groups showed normal PR and corrected QT intervals and QRS complexes. Compared to BALB/c mice, C57BL/6 mice showed a lower parasitemia peak, mortality rate, and less intense myocarditis. Thus, C57BL/6 mice infected with 500 parasites were used for subsequent analyses. At 120 dpi, a decrease in cardiac mitochondrial oxygen consumption and an increase in reactive oxygen species (ROS) were detected. When we increased the number of analyzed mice, a reduced heart rate and slightly prolonged corrected QT intervals were detected, at 120 and 150 dpi, which were then normalized at 180 dpi, thus characterizing the CIF. Y-infected mice were subjected to an exercise program on a treadmill for 4 weeks (from 150 to 180 dpi), five times per week in a 30-60-min daily training session. At 180 dpi, no alterations were detected in cardiac mitochondrial and oxidative metabolism, which were not affected by physical exercises, although ROS production increased. At 120 and 180 dpi, comparing infected and non-infected mice, no differences were observed in the levels of plasma cytokines, indicating that a crucial biomarker of the systemic inflammatory profile was absent and not affected by exercise. Compared with sedentary mice, trained Y-infected mice showed similar parasite loads and inflammatory cells but reduced cardiac fibrosis. Therefore, our data show that physical exercises promote beneficial changes that may prevent CD progression.
Although several research efforts have been made worldwide to discover novel drug candidates for the treatment of Chagas disease, the nitroimidazole drug benznidazol remains the only therapeutic ...alternative in the control of this disease. However, this drug presents reduced efficacy in the chronic form of the disease and limited safety after long periods of administration, making it necessary to search for new, more potent and safe prototypes.
We described herein the synthesis and the trypanocidalaction of new functionalized carbohydrazonamides (2-10) against trypomastigote forms of Trypanosoma cruzi.
These compounds were designed through the application of molecular hybridization concept between two potent anti-T. cruzi prototypes, the nitroimidazole derivative megazol (1) and the cinnamyl N-acylhydrazone derivative (14) which have been shown to be twice as potent in vitro as benznidazole.
The most active compounds were the (Z)-N'-((E)-3-(4-nitrophenyl)-acryloyl)-1-methyl-5- nitro-1H-imidazol-2-carbohydrazonamide (6) (IC50=9.50 μM) and the (Z)-N'-((E)-3-(4- hydroxyphe-nyl)-acryloyl)-1-methyl-5-nitro-1H-imidazol-2-carbohydrazonamide (8) (IC50=12.85 μM), which were almost equipotent to benznidazole (IC50=10.26 μM) used as standard drug. The removal of the amine group attached to the imine subunit in the corresponding N-acylhydrazone derivatives (11-13) resulted in less potent or inactive compounds. The para-hydroxyphenyl derivative (8) presented also a good selectivity index (SI = 32.94) when tested against mammalian cells from Swiss mice.
The promising trypanocidal profile of new carbohydrazonamide derivatives (6) and (8) was characterized. These compounds have proved to be a good starting point for the design of more effective trypanocidal drug candidates.
•The hemodialysis section of the Renal Health application aroused the interest of the population.•The peritoneal dialysis section was validated by specialists.•Regarding spontaneous use of the ...hemodialysis section, weight gain data was the most commonly recorded by users.
Chronic kidney disease is a worldwide public health problem, with a high prevalence of patients on dialysis. mHealth technologies can greatly support the treatment and monitoring of these patients. Thus, this study aimed to evaluate the spontaneous use of the application (app) Renal Health, a previously available technology, for patients on hemodialysis and validate content to support patients undergoing peritoneal dialysis.
The first stage consisted of evaluating the spontaneous use of the app, and the second stage consisted of methodological research for the development, evaluation, and improvement of a technological instrument for use in clinical practice as a support for patients undergoing peritoneal dialysis (PD). The association between categorical variables was performed using the chi-square test, adopting a significance level of 5%.
The app was accessed by 753 users and of these, 34 % accessed the hemodialysis section. Most accesses were in the state of São Paulo/Brazil and performed by women. The records of biochemical tests did not vary according to gender and age group (p > 0.05). The developed and validated PD section enables section control, allowing the user to manage their sessions. The analysis of the technology by the specialists showed good results for the global content validity index (CVI) regarding objectives (CVI = 0.95), structure (CVI = 0.97), and relevance (CVI = 1.0).
It is concluded that the hemodialysis section of the Renal Health app aroused the interest of the population and that the developed peritoneal dialysis section was validated by specialists.
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