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1.
Int J Mol Sci ; 25(15)2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39125711

RESUMEN

Cystatin F (CstF) is a protease inhibitor of cysteine cathepsins, including those involved in activating the perforin/granzyme cytotoxic pathways. It is targeted at the endolysosomal pathway but can also be secreted to the extracellular milieu or endocytosed by bystander cells. CstF was shown to be significantly increased in tuberculous pleurisy, and during HIV coinfection, pleural fluids display high viral loads. In human macrophages, our previous results revealed a strong upregulation of CstF in phagocytes activated by interferon γ or after infection with Mycobacterium tuberculosis (Mtb). CstF manipulation using RNA silencing led to increased proteolytic activity of lysosomal cathepsins, improving Mtb intracellular killing. In the present work, we investigate the impact of CstF depletion in macrophages during the coinfection of Mtb-infected phagocytes with lymphocytes infected with HIV. The results indicate that decreasing the CstF released by phagocytes increases the major pro-granzyme convertase cathepsin C of cytotoxic immune cells from peripheral blood-derived lymphocytes. Consequently, an observed augmentation of the granzyme B cytolytic activity leads to a significant reduction in viral replication in HIV-infected CD4+ T-lymphocytes. Ultimately, this knowledge can be crucial for developing new therapeutic approaches to control both pathogens based on manipulating CstF.


Asunto(s)
Catepsina C , Coinfección , Granzimas , Infecciones por VIH , Macrófagos , Mycobacterium tuberculosis , Humanos , Granzimas/metabolismo , Granzimas/genética , Infecciones por VIH/metabolismo , Infecciones por VIH/inmunología , Macrófagos/metabolismo , Macrófagos/inmunología , Macrófagos/microbiología , Macrófagos/virología , Coinfección/microbiología , Catepsina C/metabolismo , Catepsina C/genética , Cistatinas/metabolismo , Cistatinas/genética , Tuberculosis/metabolismo , Tuberculosis/inmunología , Tuberculosis/microbiología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , VIH-1/fisiología , Biomarcadores de Tumor
2.
Biomolecules ; 14(7)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39062562

RESUMEN

Tuberculosis and AIDS remain two of the most relevant human infectious diseases. The pathogens that cause them, Mycobacterium tuberculosis (Mtb) and HIV, individually elicit an immune response that treads the line between beneficial and detrimental to the host. Co-infection further complexifies this response since the different cytokines acting on one infection might facilitate the dissemination of the other. In these responses, the role of type I interferons is often associated with antiviral mechanisms, while for bacteria such as Mtb, their importance and clinical relevance as a suitable target for manipulation are more controversial. In this article, we review the recent knowledge on how these interferons play distinct roles and sometimes have opposite consequences depending on the stage of the pathogenesis. We highlight the dichotomy between the acute and chronic infections displayed by both infections and how type I interferons contribute to an initial control of each infection individually, while their chronic induction, particularly during HIV infection, might facilitate Mtb primo-infection and progression to disease. We expect that further findings and their systematization will allow the definition of windows of opportunity for interferon manipulation according to the stage of infection, contributing to pathogen clearance and control of immunopathology.


Asunto(s)
Infecciones por VIH , Interferón Tipo I , Mycobacterium tuberculosis , Tuberculosis , Humanos , Interferón Tipo I/metabolismo , Interferón Tipo I/inmunología , Mycobacterium tuberculosis/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/microbiología , Tuberculosis/inmunología , Tuberculosis/microbiología , Tuberculosis/metabolismo , Coinfección/inmunología , Coinfección/microbiología , Animales
3.
Pharmaceuticals (Basel) ; 17(5)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38794129

RESUMEN

Tuberculosis (TB) continues to be a major global health challenge and a leading cause of death from infectious diseases. Inspired by the results from a previous work by our group on antimycobacterial N-alkylnitrobenzamides, which are structurally related to the nitrobenzamide family of decaprenylphosphoryl-ß-d-ribose oxidase (DprE1) inhibitors, the present study explored a broad array of substituted benzamides. We particularly focused on previously unexplored 3,5-dinitrobenzamide derivatives. Starting with 3,5-dinitrobenzoic acid, we synthesized a diverse library of amides, incorporating both linear and cyclic amine moieties and also assessed the impact of terminal aromatic groups connected through ether, ester, or amide bonds on the bioactivity of the compounds. The synthesis primarily utilized nucleophilic addition/elimination, SN2, and Mitsunobu reactions. The activity was impacted mainly by two structural features, the addition of an aromatic moiety as a terminal group and the type of linker. The most interesting compounds (c2, d1, and d2, MIC = 0.031 µg/mL) exhibited activities against Mycobacterium Tuberculosis (Mtb) H37Rv comparable to isoniazid. Complementary computational studies helped elucidate potential interactions with DprE1, enhancing our understanding of the molecular basis of their action. Our findings suggest that the most active compounds provide a promising foundation for the continued development of new antimycobacterial agents.

4.
Pharmaceuticals (Basel) ; 17(5)2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38794178

RESUMEN

Tuberculosis (TB) is a disease that plagues the frailest members of society. We have developed a family of N-alkyl nitrobenzamides that exhibit promising antitubercular activities and can be considered a structural simplification of known inhibitors of decaprenylphosphoryl-ß-D-ribofuranose 2'-oxidase (DprE1), an essential Mycobacterium tuberculosis (Mtb) enzyme and an emergent antitubercular target. Hereby, we report the development of these compounds via a simple synthetic methodology as well as their stability, cytotoxicity, and antitubercular activity. Studying their in vitro activity revealed that the 3,5-dinitro and the 3-nitro-5-trifluoromethyl derivatives were the most active, and within these, the derivatives with intermediate lipophilicities presented the best activities (MIC of 16 ng/mL). Additionally, in an ex vivo macrophage model of infection, the derivatives with chain lengths of six and twelve carbon atoms presented the best results, exhibiting activity profiles comparable to isoniazid. Although the proof is not definite, the assessment of susceptibility over multiple mycobacterial species, together with the structure similarities with known inhibitors of this enzyme, support DprE1 as a likely target of action for the compounds. This idea is also reinforced by the docking studies, where the fit of our more active compounds to the DprE1 binding pocket is very similar to what was observed for known inhibitors like DNB1.

5.
Rev Med Virol ; 34(3): e2534, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38588024

RESUMEN

Since the identification of human immunodeficiency virus type 1 (HIV-1) in 1983, many improvements have been made to control viral replication in the peripheral blood and to treat opportunistic infections. This has increased life expectancy but also the incidence of age-related central nervous system (CNS) disorders and HIV-associated neurodegeneration/neurocognitive impairment and depression collectively referred to as HIV-associated neurocognitive disorders (HAND). HAND encompasses a spectrum of different clinical presentations ranging from milder forms such as asymptomatic neurocognitive impairment or mild neurocognitive disorder to a severe HIV-associated dementia (HAD). Although control of viral replication and suppression of plasma viral load with combination antiretroviral therapy has reduced the incidence of HAD, it has not reversed milder forms of HAND. The objective of this review, is to describe the mechanisms by which HIV-1 invades and disseminates in the CNS, a crucial event leading to HAND. The review will present the evidence that underlies the relationship between HIV infection and HAND. Additionally, recent findings explaining the role of neuroinflammation in the pathogenesis of HAND will be discussed, along with prospects for treatment and control.


Asunto(s)
Complejo SIDA Demencia , Enfermedades del Sistema Nervioso Central , Infecciones por VIH , VIH-1 , Humanos , Infecciones por VIH/epidemiología , Enfermedades Neuroinflamatorias , Complejo SIDA Demencia/tratamiento farmacológico , Complejo SIDA Demencia/epidemiología , Complejo SIDA Demencia/psicología , Enfermedades del Sistema Nervioso Central/etiología , Sistema Nervioso Central
6.
mBio ; 15(4): e0031924, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38441981

RESUMEN

Trypanosoma cruzi is the etiologic agent of the most prevalent human parasitic disease in Latin America, Chagas disease. Its genome is rich in multigenic families that code for virulent antigens and are present in the rapidly evolving genomic compartment named Disruptive. DNA replication is a meticulous biological process in which flaws can generate mutations and changes in chromosomal and gene copy numbers. Here, integrating high-throughput and single-molecule analyses, we were able to identify Predominant, Flexible, and Dormant Orc1Cdc6-dependent origins as well as Orc1Cdc6-independent origins. Orc1Cdc6-dependent origins were found in multigenic family loci, while independent origins were found in the Core compartment that contains conserved and hypothetical protein-coding genes, in addition to multigenic families. In addition, we found that Orc1Cdc6 density is related to the firing of origins and that Orc1Cdc6-binding sites within fired origins are depleted of a specific class of nucleosomes that we previously categorized as dynamic. Together, these data suggest that Orc1Cdc6-dependent origins may contribute to the rapid evolution of the Disruptive compartment and, therefore, to the success of T. cruzi infection and that the local epigenome landscape is also involved in this process.IMPORTANCETrypanosoma cruzi, responsible for Chagas disease, affects millions globally, particularly in Latin America. Lack of vaccine or treatment underscores the need for research. Parasite's genome, with virulent antigen-coding multigenic families, resides in the rapidly evolving Disruptive compartment. Study sheds light on the parasite's dynamic DNA replication, discussing the evolution of the Disruptive compartment. Therefore, the findings represent a significant stride in comprehending T. cruzi's biology and the molecular bases that contribute to the success of infection caused by this parasite.


Asunto(s)
Enfermedad de Chagas , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Origen de Réplica , Enfermedad de Chagas/parasitología , Dosificación de Gen , Cromosomas
7.
Antimicrob Agents Chemother ; 68(4): e0158623, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38411952

RESUMEN

Increasing evidence supports the repositioning of beta-lactams for tuberculosis (TB) therapy, but further research on their interaction with conventional anti-TB agents is still warranted. Moreover, the complex cell envelope of Mycobacterium tuberculosis (Mtb) may pose an additional obstacle to beta-lactam diffusion. In this context, we aimed to identify synergies between beta-lactams and anti-TB drugs ethambutol (EMB) and isoniazid (INH) by assessing antimicrobial effects, intracellular activity, and immune responses. Checkerboard assays with H37Rv and eight clinical isolates, including four drug-resistant strains, exposed that only treatments containing EMB and beta-lactams achieved synergistic effects. Meanwhile, the standard EMB and INH association failed to produce any synergy. In Mtb-infected THP-1 macrophages, combinations of EMB with increasing meropenem (MEM) concentrations consistently displayed superior killing activities over the individual antibiotics. Flow cytometry with BODIPY FL vancomycin, which binds directly to the peptidoglycan (PG), confirmed an increased exposure of this layer after co-treatment. This was reinforced by the high IL-1ß secretion levels found in infected macrophages after incubation with MEM concentrations above 5 mg/L, indicating an exposure of the host innate response sensors to pathogen-associated molecular patterns in the PG. Our findings show that the proposed impaired access of beta-lactams to periplasmic transpeptidases is counteracted by concomitant administration with EMB. The efficiency of this combination may be attributed to the synchronized inhibition of arabinogalactan and PG synthesis, two key cell wall components. Given that beta-lactams exhibit a time-dependent bactericidal activity, a more effective pathogen recognition and killing prompted by this association may be highly beneficial to optimize TB regimens containing carbapenems.IMPORTANCEAddressing drug-resistant tuberculosis with existing therapies is challenging and the treatment success rate is lower when compared to drug-susceptible infection. This study demonstrates that pairing beta-lactams with ethambutol (EMB) significantly improves their efficacy against Mycobacterium tuberculosis (Mtb). The presence of EMB enhances beta-lactam access through the cell wall, which may translate into a prolonged contact between the drug and its targets at a concentration that effectively kills the pathogen. Importantly, we showed that the effects of the EMB and meropenem (MEM)/clavulanate combination were maintained intracellularly. These results are of high significance considering that the time above the minimum inhibitory concentration is the main determinant of beta-lactam efficacy. Moreover, a correlation was established between incubation with higher MEM concentrations during macrophage infection and increased IL-1ß secretion. This finding unveils a previously overlooked aspect of carbapenem repurposing against tuberculosis, as certain Mtb strains suppress the secretion of this key pro-inflammatory cytokine to evade host surveillance.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Etambutol/farmacología , Etambutol/uso terapéutico , Meropenem/farmacología , Meropenem/uso terapéutico , Ácido Clavulánico/farmacología , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis/microbiología , Carbapenémicos/farmacología , beta-Lactamas/farmacología , beta-Lactamas/uso terapéutico , Pruebas de Sensibilidad Microbiana
8.
Rev. Soc. Bras. Clín. Méd ; 15(2): 80-83, 20170000. ilus
Artículo en Portugués | LILACS | ID: biblio-875548

RESUMEN

OBJETIVO: Analisar a qualidade de vida de mulheres climatéricas. MÉTODOS: A pesquisa foi realizada em uma Unidade de Saúde da Família, com 75 mulheres na faixa etária de 35 a 65 anos. Trata-se de uma pesquisa epidemiológica, transversal. A coleta de dados foi realizada por meio dos formulários Questionário de Avaliação da Qualidade de Vida, Formulário Socioeconômico e Formulário Clínico. Para análise estatística, foram utilizados o programa BioEstat 5.0 e o teste estatístico qui quadrado de proporções esperadas iguais. RESULTADOS: Entre as entrevistadas, de maioria entre 35 e 45 anos, observou-se predominância de mulheres de raça parda e com companheiro marital, com menor predominância de sintomas. As mulheres que recebiam entre dois ou mais salários mínimos apresentaram menor intensidade de sintomas, ou mesmo não os apresentaram. Estes fatores podiam estar condicionados ao tipo de atividade exercida ou às condições de trabalho. Evidenciou-se significativa prevalência de falta de ar, suor, calor intenso e ansiedade, sendo o comprometimento do componente mental o mais significativo. Em pacientes com sobrepeso ou obesidade, foi observada maior intensidade de sintomas.CONCLUSÃO: Observou-se grande impacto por conta das mudanças do período do climatério na qualidade de vida das mulheres. Muitos dos sintomas apresentados são influenciados por fatores modificáveis. O controle dos sintomas por meio de mudanças de hábitos é necessário para a manutenção da qualidade de vida.(AU)


OBJECTIVE: To analyze the quality of life of climacteric stage women. METHODS: The study was conducted at a Family Health Unit, with 75 women aged 35-65 years. This is an epidemiological, cross-sectional research. Data collection was done through the forms: Questionnaire for Assessment of Quality of Life, Socioeconomic Form, and Clinical Form. For statistical analysis, the software Bioestat 5.0, and the chi-square statistical test of equal expected proportions were used. RESULTS: Among the interviewees, most of them between 35 and 45 years of age, there was a predominance of brown women with marital partners, with a lower prevalence of the symptoms. The women earning between two or more minimum wages presented less severe symptoms, or do not have them. These factors may be conditioned to the type of activity performed or to the working conditions. There was a significant prevalence of shortness of breath, sweat, intense heat and anxiety, with the most significant impairment being to the mental component. In patients with overweight or obesity, a greater severity of symptoms was observed. CONCLUSION: A great impact in the quality of life of women was observed due to the changes of the climacteric period. Many of the symptoms presented are influenced by modifiable factors. The control of symptoms through changes in habits is necessary for keeping quality of life.(AU)


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Climaterio/metabolismo , Calidad de Vida , Salud de la Mujer , Estudios Transversales/métodos
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