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1.
BMJ Open Sport Exerc Med ; 9(3): e001641, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37485006

RESUMEN

To evaluate aerobic capacity, strength and other physiological, nutritional, and psychological variables which may influence the performance of transgender women (TW) athletes and compare them to cisgender women (CW) and cisgender men (CM) athletes, as well as changes in TW performance over the course of a year. Prospective cohort study including three groups: TW, CW and CM volleyball athletes. Subjects will be comprehensively assessed at two different moments: baseline and after 6-12 months of adequate hormonal therapy. Evaluation will comprise clinical, medical, nutritional and psychological interviews, incremental treadmill cardiopulmonary exercise testing, hand grip strength test, vertical jump test, analysis of sleep quality (Pittsburgh Sleep Quality Index), hormonal profile, echocardiogram, analysis of resting energy expenditure, assessment of bone mass and body composition through dual-energy X-ray absorptiometry scans, and untargeted metabolomic analysis. CW and CM matched by age, body mass index and level of physical activity will undergo a similar evaluation. The assessment of the strength, aerobic capacity, haematological, nutritional and psychological status of TW using gold-standard tests will contribute to understanding the impact of oestrogen therapy on the exercise performance of these athletes and how they compare with CW and CM.

2.
Front Cell Infect Microbiol ; 12: 760830, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35402315

RESUMEN

Trypanosoma cruzi, the etiological agent of Chagas disease, exhibits extensive inter- and intrastrain genetic diversity. As we have previously described, there are some genetic differences between the parental G strain and its clone D11, which was isolated by the limiting dilution method and infection of cultured mammalian cells. Electrophoretic karyotyping and Southern blot hybridization of chromosomal bands with specific markers revealed chromosome length polymorphisms of small size with additional chromosomal bands in clone D11 and the maintenance of large syntenic groups. Both G strain and clone D11 belong to the T. cruzi lineage TcI. Here, we designed intraspecific array-based comparative genomic hybridization (aCGH) to identify chromosomal regions harboring copy-number variations between clone D11 and the G strain. DNA losses were more extensive than DNA gains in clone D11. Most alterations were flanked by repeated sequences from multigene families that could be involved in the duplication and deletion events. Several rearrangements were detected by chromoblot hybridization and confirmed by aCGH. We have integrated the information of genomic sequence data obtained by aCGH to the electrophoretic karyotype, allowing the reconstruction of possible recombination events that could have generated the karyotype of clone D11. These rearrangements may be explained by unequal crossing over between sister or homologous chromatids mediated by flanking repeated sequences and unequal homologous recombination via break-induced replication. The genomic changes detected by aCGH suggest the presence of a dynamic genome that responds to environmental stress by varying the number of gene copies and generating segmental aneuploidy.


Asunto(s)
Enfermedad de Chagas , Trypanosoma cruzi , Animales , Células Clonales , Hibridación Genómica Comparativa/métodos , ADN , Genoma de Protozoos , Mamíferos/genética , Trypanosoma cruzi/genética
3.
Biochem Biophys Res Commun ; 390(3): 963-70, 2009 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-19852933

RESUMEN

Phosphatidylinositol (PI) kinases are at the heart of one of the major pathways of intracellular signal transduction. Herein, we present the first report on a survey made by similarity searches against the five human pathogenic trypanosomatids Trypanosoma brucei, Trypanosoma cruzi, Leishmania major, Leishmania braziliensis and Leishmania infantum genomes available to date for phosphatidylinositol- and related-kinases (TryPIKs). In addition to generating a panel called "The TryPIKinome", we propose a model of signaling pathways for these TryPIKs. The involvement of TryPIKs in fundamental pathways, such as intracellular signal transduction and host invasion processes, makes the study of TryPIKs an important area for further inquiry. New subtype-specific inhibitors are expected to work on individual members of the PIK family and, therefore, can presumably neutralize trypanosomatid invasion processes.


Asunto(s)
1-Fosfatidilinositol 4-Quinasa/clasificación , Diseño de Fármacos , Inhibidores Enzimáticos/química , Tripanocidas/química , Trypanosomatina/enzimología , 1-Fosfatidilinositol 4-Quinasa/antagonistas & inhibidores , 1-Fosfatidilinositol 4-Quinasa/genética , Secuencia de Aminoácidos , Androstadienos/química , Androstadienos/farmacología , Autofagia , Membrana Celular/enzimología , Citocinesis/efectos de los fármacos , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/farmacología , Humanos , Leishmania braziliensis/efectos de los fármacos , Leishmania braziliensis/enzimología , Leishmania braziliensis/crecimiento & desarrollo , Leishmania infantum/efectos de los fármacos , Leishmania infantum/enzimología , Leishmania infantum/crecimiento & desarrollo , Leishmania major/efectos de los fármacos , Leishmania major/enzimología , Leishmania major/crecimiento & desarrollo , Lisina/genética , Datos de Secuencia Molecular , Filogenia , Tripanocidas/aislamiento & purificación , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/enzimología , Trypanosoma brucei brucei/crecimiento & desarrollo , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/enzimología , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosomatina/efectos de los fármacos , Trypanosomatina/crecimiento & desarrollo , Wortmanina
4.
Int J Genomics ; 2019: 8458263, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31531340

RESUMEN

The HIV-1 virus (human immunodeficiency virus) affects 36.9 million people worldwide, with approximately 900000 deaths in 2017. The virus carrier can develop severe immunodeficiency since CD4+ T lymphocytes are the main target, leading to acquired immunodeficiency syndrome (AIDS). Despite advances in pharmacological treatment, it is still difficult to eliminate latent reservoirs, becoming one of the main obstacles for viral eradication. The CRISPR- (clustered regularly interspaced short palindromic repeat-) Cas system is a genome-editing method which uses a guide RNA, a complementary sequence to the interested site, recruiting a nuclease that can break the viral or the host cell genetic material. From this double-stranded break, cellular repair mechanisms are activated being able to generate deletions, insertions, or substitutions, in order to inactivate specific gene loci, leading to loss of function. The objective of this minireview is to synthesize the current knowledge on the application of CRISPR-Cas-based gene therapy for HIV-1. The strategies encompass all steps of the viral infection cycle, from inhibition of cell invasion, through viral replication and integration inhibition, to excision of the latent provirus. Off-target effects and ethical implications were also discussed to evaluate the safety of the approach and viability of its application in humans, respectively. Although preclinical and clinical tests are still needed, the recent results establish an exciting possibility of applying this technology for prophylaxis and treatment of HIV-1.

5.
Sci Rep ; 6: 24610, 2016 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-27113535

RESUMEN

Mevalonate kinase (MVK) is an essential enzyme acting in early steps of sterol isoprenoids biosynthesis, such as cholesterol in humans or ergosterol in trypanosomatids. MVK is conserved from bacteria to mammals, and localizes to glycosomes in trypanosomatids. During the course of T. cruzi MVK characterization, we found that, in addition to glycosomes, this enzyme may be secreted and modulate cell invasion. To evaluate the role of TcMVK in parasite-host cell interactions, TcMVK recombinant protein was produced and anti-TcMVK antibodies were raised in mice. TcMVK protein was detected in the supernatant of cultures of metacyclic trypomastigotes (MTs) and extracellular amastigotes (EAs) by Western blot analysis, confirming its secretion into extracellular medium. Recombinant TcMVK bound in a non-saturable dose-dependent manner to HeLa cells and positively modulated internalization of T. cruzi EAs but inhibited invasion by MTs. In HeLa cells, TcMVK induced phosphorylation of MAPK pathway components and proteins related to actin cytoskeleton modifications. We hypothesized that TcMVK is a bifunctional enzyme that in addition to playing a classical role in isoprenoid synthesis in glycosomes, it is secreted and may modulate host cell signaling required for T. cruzi invasion.


Asunto(s)
Interacciones Huésped-Parásitos/fisiología , Microcuerpos/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Transducción de Señal , Trypanosoma cruzi/enzimología , Citoesqueleto de Actina , Secuencia de Aminoácidos , Animales , Anticuerpos Antihelmínticos/inmunología , Dimerización , Células HeLa , Humanos , Estadios del Ciclo de Vida , Ratones , Microscopía Fluorescente , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Simulación de Dinámica Molecular , Fosforilación , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/inmunología , Estructura Cuaternaria de Proteína , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación , Alineación de Secuencia , Trypanosoma cruzi/fisiología
6.
Mol Biochem Parasitol ; 193(2): 71-4, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24583081

RESUMEN

A growing body of evidence in mammalian cells indicates that secreted vesicles can be used to mediate intercellular communication processes by transferring various bioactive molecules, including mRNAs and microRNAs. Based on these findings, we decided to analyze whether Trypanosoma cruzi-derived extracellular vesicles contain RNA molecules and performed a deep sequencing and genome-wide analysis of a size-fractioned cDNA library (16-40nt) from extracellular vesicles secreted by noninfective epimastigote and infective metacyclic trypomastigote forms. Our data show that the small RNAs contained in these extracellular vesicles originate from multiple sources, including tRNAs. In addition, our results reveal that the variety and expression of small RNAs are different between parasite stages, suggesting diverse functions. Taken together, these observations call attention to the potential regulatory functions that these RNAs might play once transferred between parasites and/or to mammalian host cells.


Asunto(s)
ARN Protozoario , Vesículas Transportadoras/genética , Trypanosoma cruzi/genética , Espacio Extracelular/genética , Biblioteca de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , ARN de Transferencia/genética
7.
Infect Genet Evol ; 25: 157-65, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24727645

RESUMEN

Chagas disease is caused by the protozoan Trypanosoma cruzi which affects 10 million people worldwide. Very few kinases have been characterized in this parasite, including the phosphatidylinositol kinases (PIKs) that are at the heart of one of the major pathways of intracellular signal transduction. Recently, we have classified the PIK family in T. cruzi using five different models based on the presence of PIK conserved domains. In this study, we have mapped PIK genes to the chromosomes of two different T. cruzi lineages (G and CL Brener) and determined the cellular localization of two PIK members. The kinases have crucial roles in metabolism and are assumed to be conserved throughout evolution. For this reason, they should display a conserved localization within the same eukaryotic species. In spite of this, there is an extensive polymorphism regarding PIK localization at both genomic and cellular levels, among different T. cruzi isolates and between T. cruzi and Trypanosomabrucei, respectively. We showed in this study that the cellular localization of two PIK-related proteins (TOR1 and 2) in the T. cruzi lineage is distinct from that previously observed in T. brucei. In addition, we identified a new PIK gene with peculiar feature, that is, it codes for a FYVE domain at N-terminal position. FYVE-PIK genes are phylogenetically distant from the groups containing exclusively the FYVE or PIK domain. The FYVE-PIK architecture is only present in trypanosomatids and in virus such as Acanthamoeba mimivirus, suggesting a horizontal acquisition. Our Bayesian phylogenetic inference supports this hypothesis. The exact functions of this FYVE-PIK gene are unknown, but the presence of FYVE domain suggests a role in membranous compartments, such as endosome. Taken together, the data presented here strengthen the possibility that trypanosomatids are characterized by extensive genomic plasticity that may be considered in designing drugs and vaccines for prevention of Chagas disease.


Asunto(s)
Fosfatidilinositol 3-Quinasas/genética , Proteínas Protozoarias/genética , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/enzimología , Teorema de Bayes , Enfermedad de Chagas/epidemiología , Evolución Molecular , Transferencia de Gen Horizontal , Genoma de Protozoos , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Filogenia , Proteínas Protozoarias/metabolismo , Trypanosoma cruzi/genética
8.
PLoS Negl Trop Dis ; 8(9): e3176, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25233456

RESUMEN

BACKGROUND: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts. METHODOLOGY/PRINCIPAL FINDINGS: The T. rangeli haploid genome is ∼ 24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heat-shock proteins. CONCLUSIONS/SIGNIFICANCE: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets.


Asunto(s)
Genoma de Protozoos , Filogenia , Trypanosoma rangeli/genética , Animales , Secuencia de Bases , ADN Protozoario/genética , Haploidia , Humanos
9.
PLoS One ; 8(5): e63738, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23667668

RESUMEN

Trypanosoma cruzi comprises a pool of populations which are genetically diverse in terms of DNA content, growth and infectivity. Inter- and intra-strain karyotype heterogeneities have been reported, suggesting that chromosomal rearrangements occurred during the evolution of this parasite. Clone D11 is a single-cell-derived clone of the T. cruzi G strain selected by the minimal dilution method and by infecting Vero cells with metacyclic trypomastigotes. Here we report that the karyotype of clone D11 differs from that of the G strain in both number and size of chromosomal bands. Large chromosomal rearrangement was observed in the chromosomes carrying the tubulin loci. However, most of the chromosome length polymorphisms were of small amplitude, and the absence of one band in clone D11 in relation to its reference position in the G strain could be correlated to the presence of a novel band migrating above or below this position. Despite the presence of chromosomal polymorphism, large syntenic groups were conserved between the isolates. The appearance of new chromosomal bands in clone D11 could be explained by chromosome fusion followed by a chromosome break or interchromosomal exchange of large DNA segments. Our results also suggest that telomeric regions are involved in this process. The variant represented by clone D11 could have been induced by the stress of the cloning procedure or could, as has been suggested for Leishmania infantum, have emerged from a multiclonal, mosaic parasite population submitted to frequent DNA amplification/deletion events, leading to a 'mosaic' structure with different individuals having differently sized versions of the same chromosomes. If this is the case, the variant represented by clone D11 would be better adapted to survive the stress induced by cloning, which includes intracellular development in the mammalian cell. Karyotype polymorphism could be part of the T. cruzi arsenal for responding to environmental pressure.


Asunto(s)
Cromosomas/genética , Reordenamiento Génico/genética , Variación Genética , Cariotipificación , Trypanosoma cruzi/citología , Trypanosoma cruzi/genética , Alelos , Animales , Células Clonales , Secuencia Conservada/genética , Sitios Genéticos/genética , Marcadores Genéticos , Tamaño del Genoma/genética , Genoma de Protozoos/genética , Técnicas de Genotipaje , Repeticiones de Microsatélite/genética , Zarigüeyas , Polimorfismo Genético , Sintenía/genética , Telómero/metabolismo , Tubulina (Proteína)/metabolismo
10.
Acta Trop ; 120(3): 231-7, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21925137

RESUMEN

A new genotype of Trypanosoma cruzi, associated with bats from anthropic areas, was recently described. Here we characterized a T. cruzi strain from this new genetic group, which could be a potential source of infection to humans. Metacyclic trypomastigotes (MT) of this strain, herein designated BAT, were compared to MT of well characterized CL and G strains, as regards the surface profile and infectivity toward human epithelial HeLa cells. BAT strain MT expressed gp82, the surface molecule recognized by monoclonal antibody 3F6 and known to promote CL strain invasion by inducing lysosomal exocytosis, as well as mucin-like molecules, but lacked gp90, which functions as a negative regulator of invasion in G strain. A set of experiments indicated that BAT strain internalization is gp82-mediated, and requires the activation of host cell phosphatidylinositol 3-kinase, protein kinase C and the mammalian target of rapamycin. MT of BAT strain were able to migrate through a gastric mucin layer, a property associated with p82 and relevant for oral infection. Gp82 was found to be a highly conserved molecule. Analysis of the BAT strain gp82 domain, containing the cell binding- and gastric mucin-binding sites, showed 91 and 93% sequence identity with G and CL strains, respectively. Hela cell invasion by BAT strain MT was inhibited by purified mucin-like molecules, which were shown to affect lysosome exocytosis required for MT internalization. Although MT of BAT strain infected host cells in vitro, they were less effective than G or CL strains in infecting mice either orally or intraperitoneally.


Asunto(s)
Enfermedad de Chagas/parasitología , Enfermedad de Chagas/veterinaria , Quirópteros/parasitología , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/genética , Animales , ADN Protozoario/química , ADN Protozoario/genética , Endocitosis , Células Epiteliales/parasitología , Femenino , Perfilación de la Expresión Génica , Células HeLa , Humanos , Proteínas de la Membrana/biosíntesis , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Proteínas Protozoarias/biosíntesis , Proteínas Protozoarias/genética , Análisis de Secuencia de ADN , Trypanosoma cruzi/aislamiento & purificación
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