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1.
Bioorg Med Chem ; 105: 117734, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677112

RESUMO

Although cancer and malaria are not etiologically nor pathophysiologically connected, due to their similarities successful repurposing of antimalarial drugs for cancer and vice-versa is known and used in clinical settings and drug research and discovery. With the growing resistance of cancer cells and Plasmodium to the known drugs, there is an urgent need to discover new chemotypes and enrich anticancer and antimalarial drug portfolios. In this paper, we present the design and synthesis of harmiprims, hybrids composed of harmine, an alkaloid of the ß-carboline type bearing anticancer and antiplasmodial activities, and primaquine, 8-aminoquinoline antimalarial drug with low antiproliferative activity, covalently bound via triazole or urea. Evaluation of their antiproliferative activities in vitro revealed that N-9 substituted triazole-type harmiprime was the most selective compound against MCF-7, whereas C1-substituted ureido-type hybrid was the most active compound against all cell lines tested. On the other hand, dimeric harmiprime was not toxic at all. Although spectrophotometric studies and thermal denaturation experiments indicated binding of harmiprims to the ds-DNA groove, cell localization showed that harmiprims do not enter cell nucleus nor mitochondria, thus no inhibition of DNA-related processes can be expected. Cell cycle analysis revealed that C1-substituted ureido-type hybrid induced a G1 arrest and reduced the number of cells in the S phase after 24 h, persisting at 48 h, albeit with a less significant increase in G1, possibly due to adaptive cellular responses. In contrast, N-9 substituted triazole-type harmiprime exhibited less pronounced effects on the cell cycle, particularly after 48 h, which is consistent with its moderate activity against the MCF-7 cell line. On the other hand, screening of their antiplasmodial activities against the erythrocytic, hepatic, and gametocytic stages of the Plasmodium life cycle showed that dimeric harmiprime exerts powerful triple-stage antiplasmodial activity, while computational analysis showed its binding within the ATP binding site of PfHsp90.


Assuntos
Antimaláricos , Antineoplásicos , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Harmina , Antimaláricos/farmacologia , Antimaláricos/química , Antimaláricos/síntese química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Harmina/farmacologia , Harmina/química , Harmina/síntese química , Proliferação de Células/efeitos dos fármacos , Relação Estrutura-Atividade , Plasmodium falciparum/efeitos dos fármacos , Estrutura Molecular , Descoberta de Drogas , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral , Testes de Sensibilidade Parasitária
2.
Molecules ; 29(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38998949

RESUMO

Newly synthesized 7-chloro-4-aminoquinoline-benzimidazole hybrids were characterized by NMR and elemental analysis. Compounds were tested for their effects on the growth of the non-tumor cell line MRC-5 (human fetal lung fibroblasts) and carcinoma (HeLa and CaCo-2), leukemia, and lymphoma (Hut78, THP-1, and HL-60) cell lines. The obtained results, expressed as the concentration at which 50% inhibition of cell growth is achieved (IC50 value), show that the tested compounds affect cell growth differently depending on the cell line and the applied dose (IC50 ranged from 0.2 to >100 µM). Also, the antiplasmodial activity of these hybrids was evaluated against two P. falciparum strains (Pf3D7 and PfDd2). The tested compounds showed potent antiplasmodial activity, against both strains, at nanomolar concentrations. Quantitative structure-activity relationship (QSAR) analysis resulted in predictive models for antiplasmodial activity against the 3D7 strain (R2 = 0.886; Rext2 = 0.937; F = 41.589) and Dd2 strain (R2 = 0.859; Rext2 = 0.878; F = 32.525) of P. falciparum. QSAR models identified the structural features of these favorable effects on antiplasmodial activities.


Assuntos
Antimaláricos , Antineoplásicos , Benzimidazóis , Desenho de Fármacos , Plasmodium falciparum , Relação Quantitativa Estrutura-Atividade , Humanos , Benzimidazóis/química , Benzimidazóis/farmacologia , Benzimidazóis/síntese química , Antimaláricos/farmacologia , Antimaláricos/síntese química , Antimaláricos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/crescimento & desenvolvimento , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinolinas/química , Quinolinas/farmacologia , Quinolinas/síntese química , Estrutura Molecular , Aminoquinolinas
3.
Angew Chem Int Ed Engl ; 63(19): e202319765, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38502093

RESUMO

The natural product chlorotonil displays high potency against multidrug-resistant Gram-positive bacteria and Plasmodium falciparum. Yet, its scaffold is characterized by low solubility and oral bioavailability, but progress was recently made to enhance these properties. Applying late-stage functionalization, we aimed to further optimize the molecule. Previously unknown reactions including a sulfur-mediated dehalogenation were revealed. Dehalogenil, the product of this reaction, was identified as the most promising compound so far, as this new derivative displayed improved solubility and in vivo efficacy while retaining excellent antimicrobial activity. We confirmed superb activity against multidrug-resistant clinical isolates of Staphylococcus aureus and Enterococcus spp. and mature transmission stages of Plasmodium falciparum. We also demonstrated favorable in vivo toxicity, pharmacokinetics and efficacy in infection models with S. aureus. Taken together, these results identify dehalogenil as an advanced lead molecule.


Assuntos
Antibacterianos , Staphylococcus aureus , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Animais , Enterococcus/efeitos dos fármacos , Estrutura Molecular , Humanos , Camundongos
4.
Bioorg Med Chem ; 94: 117468, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37696205

RESUMO

Malaria, one of the oldest parasitic diseases, remains a global health threat, and the increasing resistance of the malaria parasite to current antimalarials is forcing the discovery of new, effective drugs. Harmicines, hybrid compounds in which harmine/ß-carboline alkaloids and cinnamic acid derivatives are linked via an amide bond or a triazole ring, represent new antiplasmodial agents. In this work, we used a multiple linear regression technique to build a linear quantitative structure-activity relationship (QSAR) model, based on a group of 40 previously prepared amide-type (AT) harmicines and their antiplasmodial activities against erythrocytic stage of chloroquine-sensitive strain of P. falciparum (Pf3D7). After analysing the QSAR model, new harmicines were designed and synthesized: six amide-type, eleven carbamate-type and two ureido-type harmicines at the N-9 position of the ß-carboline core. Subsequently, we evaluated the antiplasmodial activity of the new harmicines against the erythrocytic and hepatic stages of the Plasmodium life cycle in vitro and their antiproliferative activity against HepG2 cells. UT harmicine (E)-1-(2-(7-methoxy-1-methyl-9H-pyrido[3,4-b]indol-9-yl)ethyl)-3-(3-(3-(trifluoromethyl)phenyl)allyl)urea at the N-9 position of the ß-carboline ring exhibited pronounced antiplasmodial activity against both the erythrocytic and the hepatic stages of the Plasmodium life cycle, accompanied by good selectivity towards Plasmodium.

5.
Adv Exp Med Biol ; 1439: 51-70, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37843805

RESUMO

Microorganisms are ubiquitous in diverse habitats and studying their chemical interactions with the environment and comprehend its complex relations with both hosts and environment, are crucial for the development of strategies to control microbial diseases. This chapter discusses the importance of studying microorganisms with agricultural benefits, using specialized metabolites as examples. Herein we highlight the challenges and opportunities in utilizing microorganisms as alternatives to synthetic pesticides and fertilizers in agriculture. Genome-guided investigations and improved analytical methodologies are necessary to characterize diverse and complex biomolecules produced by microorganisms. Predicting and isolating bioproducts based on genetic information have become a focus for researchers, aided by tools like antiSMASH, BiG-SCAPE, PRISM, and others. However, translating genomic data into practical applications can be complex. Therefore, integrating genomics, transcriptomics, and metabolomics enhances chemical characterization, aiding in discovering new metabolic pathways and specialized metabolites. Additionally, elicitation is one promising strategy to enhance beneficial metabolite production. Finally, identify and characterize microbial secondary metabolites remain challenging due to their low production, complex chemical structure characterization and different environmental factors necessary for metabolite in vitro production.


Assuntos
Metabolômica , Praguicidas , Metabolômica/métodos , Genômica/métodos , Redes e Vias Metabólicas , Perfilação da Expressão Gênica
6.
J Cancer Educ ; 38(3): 940-947, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36029416

RESUMO

AIM: In this study, we evaluated the impact of an integrated oral care protocol for pediatric patients undergoing antineoplastic treatment from the perspective of the multidisciplinary team, oral healthcare team, and caregivers. SUBJECT AND METHODS: This was a qualitative study carried out in the pediatric sector of a reference cancer hospital in Brazil. Focus group and individual semi-structured interview techniques were used, and the data were analyzed by the Discourse of the Collective Subject (DCS) method. RESULTS: A total of 44 professionals involved in providing care to children and adolescents with cancer and 38 caregivers were interviewed. All interviewees perceived an improvement in the patients' oral health condition. Health professionals reported a reduction in the occurrence and severity of oral mucositis (OM). Communicating with the medical team and understanding the importance of oral care to the patient's systemic condition were the greatest difficulties reported by the oral healthcare team. CONCLUSION: This implementation project contributed to establishing a complete multidisciplinary team to assist pediatric patients in all their needs during antineoplastic treatment. The integrated oral care protocol further contributed to reducing the occurrence and severity of OM by increasing its surveillance and diagnostic efficiency, which, altogether, improved the patients' quality of life.


Assuntos
Antineoplásicos , Neoplasias , Estomatite , Adolescente , Criança , Humanos , Qualidade de Vida , Neoplasias/tratamento farmacológico , Antineoplásicos/efeitos adversos , Estomatite/prevenção & controle , Estomatite/induzido quimicamente , Pacientes
7.
Int J Mol Sci ; 23(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36012590

RESUMO

Cancer and malaria are both global health threats. Due to the increase in the resistance to the known drugs, research on new active substances is a priority. Here, we present the design, synthesis, and evaluation of the biological activity of harmicens, hybrids composed of covalently bound harmine/ß-carboline and ferrocene scaffolds. Structural diversity was achieved by varying the type and length of the linker between the ß-carboline ring and ferrocene, as well as its position on the ß-carboline ring. Triazole-type harmicens were prepared using Cu(I)-catalyzed azide-alkyne cycloaddition, while the synthesis of amide-type harmicens was carried out by applying a standard coupling reaction. The results of in vitro biological assays showed that the harmicens exerted moderate antiplasmodial activity against the erythrocytic stage of P. falciparum (IC50 in submicromolar and low micromolar range) and significant and selective antiproliferative activity against the MCF-7 and HCT116 cell lines (IC50 in the single-digit micromolar range, SI > 5.9). Cell localization experiments showed different localizations of nonselective harmicene 36 and HCT116-selective compound 28, which clearly entered the nucleus. A cell cycle analysis revealed that selective harmicene 28 had already induced G1 cell cycle arrest after 24 h, followed by G2/M arrest with a concomitant drastic reduction in the percentage of cells in the S phase, whereas the effect of nonselective compound 36 on the cell cycle was much less pronounced, which agreed with their different localizations within the cell.


Assuntos
Antineoplásicos , Malária Falciparum , Antineoplásicos/química , Apoptose , Carbolinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular , Harmina , Humanos , Metalocenos/farmacologia , Relação Estrutura-Atividade
8.
Angew Chem Int Ed Engl ; 61(30): e202202816, 2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35485800

RESUMO

The rise of antimicrobial resistance poses a severe threat to public health. The natural product chlorotonil was identified as a new antibiotic targeting multidrug resistant Gram-positive pathogens and Plasmodium falciparum. Although chlorotonil shows promising activities, the scaffold is highly lipophilic and displays potential biological instabilities. Therefore, we strived towards improving its pharmaceutical properties by semisynthesis. We demonstrated stereoselective epoxidation of chlorotonils and epoxide ring opening in moderate to good yields providing derivatives with significantly enhanced solubility. Furthermore, in vivo stability of the derivatives was improved while retaining their nanomolar activity against critical human pathogens (e.g. methicillin-resistant Staphylococcus aureus and P. falciparum). Intriguingly, we showed further superb activity for the frontrunner molecule in a mouse model of S. aureus infection.


Assuntos
Antimaláricos , Malária Falciparum , Staphylococcus aureus Resistente à Meticilina , Animais , Antibacterianos/farmacologia , Antimaláricos/farmacologia , Compostos de Epóxi/farmacologia , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Staphylococcus aureus
9.
Molecules ; 26(8)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33921170

RESUMO

Malaria is one of the most life-threatening infectious diseases and constitutes a major health problem, especially in Africa. Although artemisinin combination therapies remain efficacious to treat malaria, the emergence of resistant parasites emphasizes the urgent need of new alternative chemotherapies. One strategy is the repurposing of existing drugs. Herein, we reviewed the antimalarial effects of marketed antibiotics, and described in detail the fast-acting antibiotics that showed activity in nanomolar concentrations. Antibiotics have been used for prophylaxis and treatment of malaria for many years and are of particular interest because they might exert a different mode of action than current antimalarials, and can be used simultaneously to treat concomitant bacterial infections.


Assuntos
Antimaláricos/uso terapêutico , Reposicionamento de Medicamentos/métodos , Animais , Antibacterianos/uso terapêutico , Resistência a Medicamentos/genética , Humanos , Malária/fisiopatologia , Plasmodium falciparum/genética , Plasmodium falciparum/patogenicidade
10.
J Community Psychol ; 49(1): 95-117, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32840883

RESUMO

Disasters affect sociospatial links in a dynamic and unstable meshwork of aspects that are reconfigured. In this sense, accounting for this complexity is central to analyze the transformation of the sociospatial linkage of the affected people and communities. Addressing from community environmental psychology, we propose the concept of assemblage to guide a situated reading of subjective, material, and community aspects present in a reconstruction process after a disaster. Following a qualitative methodology, using spatially referenced narrative interviews (n = 16) and thematic analysis, it is described how these links are presented in a community that lived the mega-fire of a part of the city of Valparaíso in Chile. The results describe that the experience of being a community is a variable flow within a process defined by an ever-emerging configuration of spatial, technological, personal, social, and sensory characteristics. We conclude by pointing out the qualities of the communities when considered from an assemblage perspective.


Assuntos
Desastres , Chile , Cidades , Humanos
11.
Exp Parasitol ; 209: 107826, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31881207

RESUMO

Protozoan parasites like Leishmania amazonensis are excellent models to test the effects of new drugs against a functional molecular arsenal used to establish successfully an infection in the vertebrate host, where they invade the cells of the monocytic system. However, little is known about the influence of metal ions on the cellular functionality of the infective forms of L. amazonensis. In the present work, we show that ZnCl2 (an essential metal to cellular metabolism) did not induce drastic effects on the survival of the promastigote under the conditions tested. However, incubation of ZnCl2 prior to subsequent treatment with CdCl2 and HgCl2 led to a drastic toxic effect on parasite survival in vitro. Nonessential metals such as CdCl2 and HgCl2 promoted a drastic effect on parasite survival progressively with increasing dose and time of exposure. Notably, HgCl2 produced an effective elimination of the parasite in doses/time smaller than the CdCl2. This toxic action induced in the parasite a high condensation of the nuclear heterochromatin, besides the absence or de-structuring of functional organelles such as glycosomes, acidocalcisomes, and mitochondria in the cytoplasm. Our results suggest that promastigotes of L. amazonensis are sensitive to the toxic activity of nonessential metals, and that this activity increases when parasites are previously exposed to Zn. To summarize, toxic effects of the tested metals are dose and time dependent and can be used as a study model to better understand the functionality of the molecular arsenal responsible for the parasitism.


Assuntos
Cloreto de Cádmio/farmacologia , Cloretos/farmacologia , Leishmania mexicana/efeitos dos fármacos , Cloreto de Mercúrio/farmacologia , Compostos de Zinco/farmacologia , Humanos , Concentração Inibidora 50 , Leishmania mexicana/crescimento & desenvolvimento , Leishmania mexicana/ultraestrutura , Microscopia Eletrônica de Transmissão
12.
Molecules ; 25(19)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32977642

RESUMO

Harmicines represent hybrid compounds composed of ß-carboline alkaloid harmine and cinnamic acid derivatives (CADs). In this paper we report the synthesis of amide-type harmicines and the evaluation of their biological activity. N-harmicines 5a-f and O-harmicines 6a-h were prepared by a straightforward synthetic procedure, from harmine-based amines and CADs using standard coupling conditions, 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo [4,5-b]pyridinium 3-oxid hexafluorophosphate (HATU) and N,N-diisopropylethylamine (DIEA). Amide-type harmicines exerted remarkable activity against the erythrocytic stage of P. falciparum, in low submicromolar concentrations, which was significantly more pronounced compared to their antiplasmodial activity against the hepatic stages of P. berghei. Furthermore, a cytotoxicity assay against the human liver hepatocellular carcinoma cell line (HepG2) revealed favorable selectivity indices of the most active harmicines. Molecular dynamics simulations demonstrated the binding of ligands within the ATP binding site of PfHsp90, while the calculated binding free energies confirmed higher activity of N-harmicines 5 over their O-substituted analogues 6. Amino acids predominantly affecting the binding were identified, which provided guidelines for the further derivatization of the harmine framework towards more efficient agents.


Assuntos
Antimaláricos/farmacologia , Alcaloides Indólicos/farmacologia , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Feminino , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/metabolismo , Fígado/efeitos dos fármacos , Fígado/parasitologia , Simulação de Dinâmica Molecular , Plasmodium berghei/metabolismo , Plasmodium berghei/fisiologia , Plasmodium falciparum/metabolismo , Plasmodium falciparum/fisiologia , Conformação Proteica
13.
Artigo em Inglês | MEDLINE | ID: mdl-31109978

RESUMO

Ivermectin is the drug of choice for many parasitic infections, with more than one billion doses being distributed in onchocerciasis programs. The drug has been put into focus recently by the malaria community because of its potential to kill blood-sucking mosquitoes, thereby reducing malaria transmission. However, the activity of ivermectin against the malaria parasite itself has been only partly investigated. This study aimed to investigate the in vitro activity of ivermectin against asexual and sexual stages of Plasmodium falciparum Both asexual and late-stage gametocytes were incubated with ivermectin and control drugs in vitro The growth-inhibiting effects were assessed for asexual stages of different Plasmodium falciparum laboratory strains and culture-adapted clinical isolates using the histidine-rich protein 2 enzyme-linked immunosorbent assay technique. The effect against stage IV/V gametocytes was evaluated based on ATP quantification. Ivermectin showed activities at nanomolar concentrations against asexual stages (50% inhibitory concentration of ∼100 nM) and stage IV/V gametocytes (500 nM) of P. falciparum Stage-specific assays suggested that ivermectin arrests the parasite cycle at the trophozoite stage. Ivermectin might add a feature to its "wonder drug" properties with activity against asexual stages of the malaria parasite Plasmodium falciparum The observed activities might be difficult to reach with current regimens but will be more relevant with future high-dose regimens under investigation. Further studies should be performed to confirm these results in vitro and in vivo.


Assuntos
Antimaláricos/farmacologia , Ivermectina/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/fisiologia , Antimaláricos/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Ivermectina/administração & dosagem , Malária Falciparum/parasitologia , Plasmodium falciparum/isolamento & purificação , Reprodução Assexuada/efeitos dos fármacos , Trofozoítos/efeitos dos fármacos
14.
Amino Acids ; 51(10-12): 1633-1648, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31654210

RESUMO

For medical use of proteins and peptide-based drugs, it is desirable to have small biologically active sequences because they improve stability, reduce side effects, and production costs. Several plant defensins have their biological activities imparted by a sequence named γ-core. Vu-Def, a Vigna unguiculata defensin, has activity against Leishmania amazonensis, which is one etiological agent of leishmaniasis and for which new drugs are needed. Our intention was to understand if the region comprising the Vu-Def γ-core is responsible for the biological activity against L. amazonensis and to unveil its mechanism of action. Different microbiological assays with L. amazonensis in the presence of the synthetic peptide A36,42,44γ32-46Vu-Def were done, as well as ultrastructural and fluorescent analyses. A36,42,44γ32-46Vu-Def showed biological activity similar to Vu-Def. A36,42,44γ32-46Vu-Def (74 µM) caused 97% inhibition of L. amazonensis culture and parasites were unable to regrow in fresh medium. The cells of the treated parasites showed morphological alterations by ultrastructural analysis and fluorescent labelings that corroborate with the data of the organelles alterations. The general significance of our work is based on the description of a small synthetic peptide, A36,42,44γ32-46Vu-Def, which has activity on L. amazonensis and that the interaction between A36,42,44γ32-46Vu-Def-L. amazonensis results in parasite inhibition by the activation of an apoptotic-like cell death pathway.


Assuntos
Apoptose/efeitos dos fármacos , Defensinas/química , Leishmania/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Vigna/química , Sequência de Aminoácidos , Defensinas/farmacologia , Leishmania/crescimento & desenvolvimento , Modelos Moleculares , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Estrutura Secundária de Proteína , Sementes/química
15.
Can J Microbiol ; 64(7): 455-464, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29586486

RESUMO

Plant defensins are plant antimicrobial peptides that present diverse biological activities in vitro, including the elimination of Leishmania amazonensis. Plant defensins are considered promising candidates for the development of new drugs. This protozoan genus has great epidemiological importance and the mechanism behind the protozoan death by defensins is unknown, thus, we chose L. amazonensis for this study. The aim of the work was to analyze the possible toxic mechanisms of Vu-Defr against L. amazonensis. For analyses, the antimicrobial assay was repeated as previously described, and after 24 h, an aliquot of the culture was tested for viability, membrane perturbation, mitochondrial membrane potential, reactive oxygen species (ROS) and nitric oxide (NO) inductions. The results of these analyses indicated that after interaction with L. amazonensis, the Vu-Defr causes elimination of promastigotes from culture, membrane perturbation, mitochondrial membrane collapse, and ROS induction. Our analysis demonstrated that NO is not produced after Vu-Defr and L. amazonensis interaction. In conclusion, our work strives to help to fill the gap relating to effects caused by plant defensins on protozoan and thus better understand the mechanism of action of this peptide against L. amazonensis.


Assuntos
Anti-Infecciosos/farmacologia , Defensinas/farmacologia , Leishmania/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Vigna/química , Animais , Membrana Celular/metabolismo , Extratos Vegetais/toxicidade , Proteínas Recombinantes/farmacologia , Sementes/química
16.
Parasitol Res ; 117(4): 1245-1256, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29455419

RESUMO

Toxoplasma gondii, the etiological agent of toxoplasmosis, infects nucleated cells and then resides and multiplies within a parasitophorous vacuole. For this purpose, the parasite secretes many virulence factors for the purpose of invading and subverting the host microbicidal defenses in order to facilitate its survival in the intracellular milieu. Essential metals are structural components of proteins and enzymes or cofactors of enzymatic reactions responsible for these parasitic survival mechanisms. However, an excess of non-essential or essential metals can lead to parasite death. Thus, infected host cells were incubated with 20 µM ZnCl2 in conjunction with 3 µM CdCl2 or HgCl2 for 12 h in order to investigate cellular events and organelle damage related to intracellular parasite death and elimination. In the presence of these metals, the tachyzoites undergo lipid uptake and transport impairment, functional and structural mitochondrial disorders, DNA condensation, and acidification of the parasitophorous vacuole, thus leading to parasite death. Additional research has suggested that lysosome-vacuole fusion was involved in parasite elimination since acid phosphatases were found inside the parasitophorous vacuole, and vacuoles containing parasites were also positive for autophagy. In conclusion, low concentrations of CdCl2, HgCl2, and ZnCl2 can cause damage to Toxoplasma gondii organelles, leading to loss of viability, organelle death, and elimination without causing toxic effects to host cells.


Assuntos
Cloreto de Cádmio/farmacologia , Cloretos/farmacologia , Cloreto de Mercúrio/farmacologia , Toxoplasma/efeitos dos fármacos , Vacúolos/efeitos dos fármacos , Compostos de Zinco/farmacologia , Animais , Autofagia , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Interações Hospedeiro-Parasita/efeitos dos fármacos , Lisossomos , Macaca mulatta , Mitocôndrias/patologia , Desnaturação de Ácido Nucleico/efeitos dos fármacos , Toxoplasma/patogenicidade , Vacúolos/parasitologia , Vacúolos/patologia , Fatores de Virulência
17.
Cell Tissue Res ; 369(2): 287-301, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28374150

RESUMO

Renovascular hypertension (RVH) is a progressive disease, leading to chronic kidney disease when untreated and no specific treatment is available. Therefore, development of new therapeutic modalities is imperative. RVH is triggered by renal artery stenosis and subsequent renin-angiotensin-aldosterone system activation; it can be experimentally induced by the 2 Kidneys-1 Clip (2K1C) model. This study investigates the therapeutic potential of renal subcapsular mesenchymal stem cell (MSC) infusion in 2K1C rats. Renal morphological and functional changes were analyzed, including Na++K+-ATPase activity and expression, renin angiotensin-converting enzyme (ACE) and angiotensin-II type 1 (AT1R) and type 2 (AT2R) receptors expression. 2K1C rats developed hypertension accompanied by renin upregulation (clipped kidney) and renal Na++K+-ATPase activity and expression reduction. MSC therapy decreased systolic blood pressure, renin, ACE, and AT1R, upregulated AT2R and podocin expression and restored renal Na++K+-ATPase activity and expression. In addition, MSC improved renal morphology, reduced fibrosis and TGF-ß expression in the clipped kidney, decreased proteinuria and restored protein plasma levels. In conclusion, transplantation into a renal subcapsule is an efficient route and MSC is a good candidate for cell therapy, which may represent an interesting approach for chronic kidney disease treatment.


Assuntos
Células da Medula Óssea/citologia , Hipertensão Renovascular/enzimologia , Hipertensão Renovascular/fisiopatologia , Rim/enzimologia , Rim/fisiopatologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Apoptose , Pressão Sanguínea , Proliferação de Células , Rastreamento de Células , Colágeno/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Hipertensão Renovascular/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Rim/metabolismo , Rim/patologia , Testes de Função Renal , Masculino , Proteínas de Membrana/metabolismo , Peptidil Dipeptidase A/metabolismo , Ratos Wistar , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Renina , Sístole , Regulação para Cima , Proteína X Associada a bcl-2/metabolismo
18.
Biometals ; 30(6): 955-974, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29081021

RESUMO

Trypanosoma cruzi has many molecules that need metallic elements to work, allowing cell invasion and the establishment of infection, causing Chagas disease. Nonetheless, knowledge regarding how the parasites address metals and maintain homeostasis is lacking. To study this relationship, zinc, cadmium and mercury were chosen. Epimastigote, trypomastigote and intracellular forms of T. cruzi were incubated with these metals for different times and at different concentrations. In general, epimastigotes were the most sensitive and trypomastigotes the most resistant to metals. ZnCl2 induced low toxic effects to all parasite forms. Although the parasites were very sensitive to the toxic effects of CdCl2 and HgCl2, pretreatment with ZnCl2 decreased the death rate. The trypomastigotes pretreated with CdCl2 were unable to infect the host cells, and the treated intracellular forms were damaged after 2 h of incubation, when the toxic effects were poorly reverted. New insights on metal toxicity mechanisms are provided, helping to understand how metallic ions influence the parasite's biochemical and physiological processes.


Assuntos
Metais/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/fisiologia , Animais , Cloreto de Cádmio/farmacologia , Cloretos/farmacologia , Chlorocebus aethiops , Mercúrio/farmacologia , Trypanosoma cruzi/patogenicidade , Trypanosoma cruzi/ultraestrutura , Células Vero , Compostos de Zinco/farmacologia
19.
Exp Cell Res ; 336(1): 15-22, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25978973

RESUMO

Mitochondrial dysfunction has been associated with liver cholestatis. Toxic bile salt accumulation leads to chronic injury with mitochondrial damage, ROS increase and apoptosis, resulting in liver dysfunction. This study aimed to analyze mitochondrial bioenergetics in rats with hepatic fibrosis induced by bile duct ligation (BDL) after BMMNC transplantation. Livers were collected from normal rats, fibrotic rats after 14 and 21 days of BDL (F14d and F21d) and rats that received BMMNC at 14 days of BDL, analyzed after 7 days. F21d demonstrated increased collagen I content and consequently decrease after BMMNC transplantation. Both F14d and F21d had significantly reduced mitochondrial oxidation capacity and increased mitochondrial uncoupling, which were restored to levels similar to those of normal group after BMMNC transplantation. In addition, F21d had a significantly increase of UCP2, and reduced PGC-1α content. However, after BMMNC transplantation both proteins returned to levels similar to normal group. Moreover, F14d had a significantly increase in 4-HNE content compared to normal group, but after BMMNC transplantation 4-HNE content significantly reduced, suggesting oxidative stress reduction. Therefore, BMMNC transplantation has a positive effect on hepatic mitochondrial bioenergetics of cholestatic rats, increasing oxidative capacity and reducing oxidative stress, which, in turn, contribute to liver function recover.


Assuntos
Transplante de Medula Óssea , Colestase/prevenção & controle , Metabolismo Energético , Cirrose Hepática/prevenção & controle , Fígado/fisiopatologia , Mitocôndrias/metabolismo , Estresse Oxidativo , Animais , Western Blotting , Células Cultivadas , Colestase/metabolismo , Colestase/patologia , Peroxidação de Lipídeos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Mitocôndrias/patologia , Oxirredução , Ratos , Ratos Wistar
20.
Biochem Cell Biol ; 93(4): 367-75, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26151357

RESUMO

Stem cells are characterized by their ability to differentiate into multiple cell lineages and display the paracrine effect. The aim of this work was to evaluate the effect of therapy with bone marrow-derived cells (BMCs) on glucose, lipid metabolism, and aortic wall remodeling in mice through the administration of a high-fat diet and subsequent BMCs transplantation. C57BL/6 mice were fed a control diet (CO group) or an atherogenic diet (AT group). After 16 weeks, the AT group was divided into 4 subgroups: an AT 14 days group and AT 21 days group that were given an injection of vehicle and sacrificed after 14 and 21 days, respectively, and an AT-BMC 14 days group and AT-BMC 21 days group that were given an injection of BMCs and sacrificed after 14 and 21 days, respectively. The BMCs transplant had reduced blood glucose, triglycerides, and total cholesterol. There was no significant difference in relation to body mass between the transplanted groups and non-transplanted groups, and all were different than CO. There was no significant difference in the glycemic curve among AT 14 days, AT-BMC 14 days, and AT 21 days, and these were different than the CO and the AT-BMC 21 days groups. The increased thickness of the aortic wall was observed in all atherogenic groups, but was significantly smaller in group AT-BMC 21 days compared to AT 14 days and AT 21 days. Vacuoles in the media tunic, delamination and the thinning of the elastic lamellae were observed in AT 14 days and AT 21 days. The smallest number of these was displayed on the AT-BMC 14 days and AT-BMC 21 days. Marking to CD105, CD133, and CD68 were observed in AT 14 days and AT 21 days. These markings were not observed in AT-BMC 14 days or in AT-BMC 21 days. Electron micrographs show the beneficial remodeling in AT-BMC 14 days and AT-BMC 21 days, and the structural organization was similar to the CO group. Vesicles of pinocytosis, projection of smooth muscle cells, and delamination of the internal elastic lamina are seen in groups AT 14 days and AT 21 days. Endothelial cells were preserved, and regular and continuous contour in internal elastic lamelae were observed in the CO, the AT-BMC 14 days, and AT-BMC 21 days groups. In conclusion, in an atherosclerotic model using mice and atherogenic diet, the injection of BMCs improves glucose, lipid metabolism, and causes a beneficial remodeling of the aortic wall.


Assuntos
Aorta/patologia , Aterosclerose/terapia , Transplante de Medula Óssea , Animais , Aorta/ultraestrutura , Glicemia/análise , Peso Corporal , Colesterol/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Triglicerídeos/sangue
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