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1.
Artigo em Inglês | MEDLINE | ID: mdl-39292629

RESUMO

BACKGROUND: Aldosterone excess chronically induces oxidative stress and cell proliferation. Previously, a single study investigated primary aldosteronism (PA) in patients with papillary thyroid cancer (PTC), albeit without a matched control group. METHODS: We conducted a propensity score matched case-control study to investigate the association between PA and PTC in individuals with arterial hypertension (HT). PA was investigated in 137 patients with PTC and HT. The control group included 137 (1:1) age, sex-, and body mass index (BMI)-matched individuals with HT. We conducted a secondary analysis in which the controls were also matched according to HT stage. RESULTS: The prevalence of PA was 29.20% (95% confidence interval [CI], 21.91%-37.68%) in the PTC group and 20.44% (95% CI, 14.22%-28.35%) in the controls not matched for HT stage (p = 0.093). Although the PA prevalence was similar in both groups, the frequency of severe HT (stage III or resistant) was significantly lower in the PTC group (23%) compared to the hypertensive controls (73%, p < 0.001). After matching the controls by HT stage, the prevalence of PA in the PTC group was significantly higher compared to the hypertensive controls (9.56%; 95% CI, 5.39%-16.1%, p < 0.0001). In the multivariable analysis, PTC was independently associated with PA in both unmatched hypertensive individuals (odds ratio [OR] 4.74; 95% CI, 2.26-10.55; p< 0.001) and in those matched for HT stage (OR 5.88, 95% CI, 2.79-13.37; p< 0.001). CONCLUSION: PTC was an independent variable associated with a diagnosis of PA in hypertensive individuals. Therefore, we propose the association between PTC and HT as a new recommendation for PA screening regardless of HT severity.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39244493

RESUMO

Phaeochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors with clinical heterogeneity and a high association with hereditary disease, affecting approximately 30 % of the cases. Differences in the presentation and genetic etiologies of PPGLs have been demonstrated between Chinese and European patients. The frequency of germline genetic diagnosis was remarkably higher in Brazilian patients (∼50 %) compared with other cohorts (Chinese 21 %, European 31 %, and The Cancer Genome Atlas Program cohort 27 %). Interestingly, germline SDHB genetic defects were also more prevalent in Brazilian patients (17 %) with PPGLs when compared with other cohorts (3-9 %). The SDHB exon 1 deletion was responsible for approximately 50 % of the SDHB pathogenic/likely pathogenic variants in Brazilian patients with PPGLs due to a founder effect. The germline SDHB exon 1 deletion represents ∼10 % of the germline drivers in Brazilian patients (and possibly in Latin America). Therefore, a single diagnostic PCR for the SDHB exon 1 deletion might be very useful in clinical practice for genetic testing and counseling of patients with PPGLs in Latin America.

3.
PLoS One ; 19(5): e0292152, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38753846

RESUMO

In the protozoan parasite Leishmania, most genes encoding for ribosomal proteins (RPs) are present as two or more copies in the genome. However, their untranslated regions (UTRs) are predominantly divergent and might be associated with a distinct regulation of the expression of paralogous genes. Herein, we investigated the expression profiles of two RPs (S16 and L13a) encoded by duplicated genes in Leishmania major. The genes encoding for the S16 protein possess identical coding sequences (CDSs) and divergent UTRs, whereas the CDSs of L13a diverge by two amino acids and by their UTRs. Using CRISPR/Cas9 genome editing, we generated knockout (Δ) and endogenously tagged transfectants for each paralog of L13a and S16 genes. Combining tagged and Δ cell lines we found evidence of differential expression of both RPS16 and RPL13a isoforms throughout parasite development, with one isoform consistently more abundant than its respective copy. In addition, compensatory expression was observed for each paralog upon deletion of the corresponding isoform, suggesting functional conservation between these proteins. This differential expression pattern relates to post-translational processes, given compensation occurs at the level of the protein, with no alterations detected at transcript level. Ribosomal profiles for RPL13a indicate a standard behavior for these paralogues suggestive of interaction with heavy RNA-protein complexes, as already reported for other RPs in trypanosomatids. We identified paralog-specific bound to their 3'UTRs which may be influential in regulating paralog expression. In support, we identified conserved cis-elements within the 3'UTRs of RPS16 and RPL13a; cis-elements exclusive to the UTR of the more abundant paralog or to the less abundant ones were identified.


Assuntos
Leishmania major , Proteínas de Protozoários , Proteínas Ribossômicas , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Leishmania major/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Sistemas CRISPR-Cas , Regulação da Expressão Gênica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
4.
J Endocr Soc ; 8(1): bvad147, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38075562

RESUMO

Context: Confirmatory tests represent a fundamental step in primary aldosteronism (PA) diagnosis, but they are laborious and often require a hospital environment due to the risks involved. Objective: To evaluate the efficacy of oral furosemide as a new confirmatory test for PA diagnosis. Methods: We prospectively evaluated the diagnostic performance of 80 mg of oral furosemide in 64 patients with PA and 22 with primary hypertension (controls). Direct renin concentration (DRC) was measured before, and 2 hours and 3 hours after the oral furosemide. In addition, the oral furosemide test was compared with 2 other confirmatory tests: the furosemide upright test (FUT) and saline infusion test (SIT) or captopril challenge test (CCT) in all patients with PA. Results: The cut-off of 7.6 µU/mL for DRC at 2 hours after oral furosemide had a sensitivity of 92%, specificity of 82%, and accuracy of 90% for PA diagnosis. In 5 out of 6 controls with low-renin hypertension, which might represent a PA spectrum, renin remained suppressed. Excluding these 6 controls with low-renin hypertension, the DRC cut-off of 10 µU/mL at 2 hours after oral furosemide had a sensitivity of 95.3%, specificity of 93.7% and accuracy of 95% for PA diagnosis. DRC after 3 hours of oral furosemide did not improve diagnostic performance. Using the cut-off of 10 µU/mL, the oral furosemide test and the FUT were concordant in 62 out of 64 (97%) patients with PA. Only 4 out of 64 cases with PA (6.4%) ended the oral furosemide test with potassium <3.5 mEq/L. Hypotension was not evidenced in any patient with PA during the test. Conclusion: The oral furosemide test was safe, well-tolerated and represents an effective strategy for PA investigation.

5.
Nat Commun ; 14(1): 1049, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36828815

RESUMO

Intracellular parasites from the Leishmania genus cause Leishmaniasis, a disease affecting millions of people worldwide. NLRP3 inflammasome is key for disease outcome, but the molecular mechanisms upstream of the inflammasome activation are still unclear. Here, we demonstrate that despite the absence of pyroptosis, Gasdermin-D (GSDMD) is active at the early stages of Leishmania infection in macrophages, allowing transient cell permeabilization, potassium efflux, and NLRP3 inflammasome activation. Further, GSDMD is processed into a non-canonical 25 kDa fragment. Gsdmd-/- macrophages and mice exhibit less NLRP3 inflammasome activation and are highly susceptible to infection by several Leishmania species, confirming the role of GSDMD for inflammasome-mediated host resistance. Active NLRP3 inflammasome and GSDMD are present in skin biopsies of patients, demonstrating activation of this pathway in human leishmaniasis. Altogether, our findings reveal that Leishmania subverts the normal functions of GSDMD, an important molecule to promote inflammasome activation and immunity in Leishmaniasis.


Assuntos
Leishmania , Leishmaniose , Humanos , Camundongos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Gasderminas , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Leishmania/metabolismo , Piroptose/fisiologia
6.
J Clin Endocrinol Metab ; 108(8): 2105-2114, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-36652439

RESUMO

CONTEXT: Limited information is available concerning the genetic spectrum of pheochromocytoma and paraganglioma (PPGL) patients in South America. Germline SDHB large deletions are very rare worldwide, but most of the individuals harboring the SDHB exon 1 deletion originated from the Iberian Peninsula. OBJECTIVE: Our aim was to investigate the spectrum of SDHB genetic defects in a large cohort of Brazilian patients with PPGLs. METHODS: Genetic investigation of 155 index PPGL patients was performed by Sanger DNA sequencing, multiplex ligation-dependent probe amplification, and/or target next-generation sequencing panel. Common ancestrality was investigated by microsatellite genotyping with haplotype reconstruction, and analysis of deletion breakpoint. RESULTS: Among 155 index patients, heterozygous germline SDHB pathogenic or likely pathogenic variants were identified in 22 cases (14.2%). The heterozygous SDHB exon 1 complete deletion was the most frequent genetic defect in SDHB, identified in 8 out of 22 (36%) of patients. Haplotype analysis of 5 SDHB flanking microsatellite markers demonstrated a significant difference in haplotype frequencies in a case-control permutation test (P = 0.03). More precisely, 3 closer/informative microsatellites were shared by 6 out of 8 apparently unrelated cases (75%) (SDHB-GATA29A05-D1S2826-D1S2644 | SDHB-186-130-213), which was observed in only 1 chromosome (1/42) without SDHB exon 1 deletion (X2 = 29.43; P < 0.001). Moreover, all cases with SDHB exon 1 deletion had the same gene breakpoint pattern of a 15 678 bp deletion previously described in the Iberian Peninsula, indicating a common origin. CONCLUSION: The germline heterozygous SDHB exon 1 deletion was the most frequent genetic defect in the Brazilian PPGL cohort. Our findings demonstrated a founder effect for the SDHB exon 1 deletion in Brazilian patients with paragangliomas.


Assuntos
Neoplasias das Glândulas Suprarrenais , Paraganglioma , Feocromocitoma , Humanos , Succinato Desidrogenase/genética , Efeito Fundador , Brasil/epidemiologia , Paraganglioma/genética , Paraganglioma/patologia , Feocromocitoma/genética , Éxons/genética , Neoplasias das Glândulas Suprarrenais/genética , Mutação em Linhagem Germinativa
7.
Front Cell Infect Microbiol ; 11: 718028, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737973

RESUMO

Host manipulation is a common strategy for invading pathogens. Trypanosoma cruzi, the causative agent of Chagas Disease, lives intracellularly within host cells. During infection, parasite-associated modifications occur to the host cell metabolism and morphology. However, little is known about the effect of T. cruzi infection on the host cell nucleus and nuclear functionality. Here, we show that T. cruzi can modulate host transcription and splicing machinery in non-professional phagocytic cells during infection. We found that T. cruzi regulates host RNA polymerase II (RNAPII) in a time-dependent manner, resulting in a drastic decrease in RNAPII activity. Furthermore, host cell ribonucleoproteins associated with mRNA transcription (hnRNPA1 and AB2) are downregulated concurrently. We reasoned that T. cruzi may hijack the host U2AF35 auxiliary factor, a key regulator for RNA processing, as a strategy to affect the splicing machinery activities directly. In support of our hypothesis, we carried out in vivo splicing assays using an adenovirus E1A pre-mRNA splicing reporter, showing that intracellular T. cruzi directly modulates the host cells by appropriating U2AF35. For the first time, our results provide evidence of a complex and intimate molecular relationship between T. cruzi and the host cell nucleus during infection.


Assuntos
Doença de Chagas , Parasitos , Trypanosoma cruzi , Animais , Núcleo Celular , Transcrição Gênica , Trypanosoma cruzi/genética
8.
Tumour Biol ; 43(1): 263-278, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34633333

RESUMO

BACKGROUND: Expression dysregulation of HOX homeobox genes has been observed in several cancers, including head and neck squamous cell carcinoma (HNSC). Although characterization of HOX gene roles in HNSC development has been reported, there is still a need to better understand their real contribution to tumorigenesis. OBJECTIVE: The present study aimed to evaluate the contribution of the protein-coding HOX genes (HOXA10, HOXC9, HOXC10, and HOXC13) in cellular processes related to carcinogenesis and progression of the HNSC. METHODS: Expression of HOX genes was analyzed in HNSC RNA-Seq data from The Cancer Genome Atlas (TCGA) and by RT-qPCR in different tumor cell lines. siRNA-mediated knockdown of HOXA10, HOXC9, HOXC10 or HOXC13 was performed in HNSC cell lines, and predicted transcriptional targets HOX genes was analyzed by bioinformatic. RESULTS: Thirty-one out of the 39 mammalian HOX genes were found upregulated in HNSC tissues and cell lines. The HOXC9, HOXC10 or HOXC13 knockdown attenuated cell migration, and lead to downregulation of epithelial-mesenchymal transition (EMT) markers, which were predicted as transcriptional targets of these three HOX genes. Diminished colony formation and cell cycle arrest after HOXC10 or HOXC13 knockdown were also observed, corroborating the fact that there was an enrichment for genes in proliferation/cell cycle pathways. CONCLUSIONS: In summary, we revealed roles for HOXC9, HOXC10, and HOXC13 in cell migration and proliferation/cell cycle progression in HNSC cells and suggested that those HOX members contribute to HNSC development possibly by regulating tumor growth and metastasis.


Assuntos
Genes Homeobox/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Animais , Biomarcadores Tumorais/genética , Carcinogênese/genética , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Regulação para Cima
9.
Infect Genet Evol ; 88: 104671, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33301989

RESUMO

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi. During the chronic phase of disease, while most infected people do not present symptoms, characterizing the asymptomatic form, some patients develop the cardiac form or chronic chagasic cardiomyopathy, which is considered the most severe manifestation of this disease. Considering that the activation of the PI3Kγ signaling pathway is essential for an efficient immune response against T. cruzi infection, we evaluated the PIK3CG C > T (rs1129293) polymorphism in exon 3 of this gene, which encodes the catalytic subunit of PI3Kγ. The PIK3CG CT and TT genotypes were found to be associated with an increased risk of developing the cardiac form of the disease rather than the asymptomatic or digestive forms. In conclusion, the presence of the T allele at single or double doses may differentiate the cardiac from other clinical manifestations of Chagas disease. This finding should help in further studies to evaluate the mechanisms underlying the differential association of PIK3CG in Chagas disease.


Assuntos
Domínio Catalítico/genética , Cardiomiopatia Chagásica/genética , Doença de Chagas/genética , Doença de Chagas/parasitologia , Classe Ib de Fosfatidilinositol 3-Quinase/genética , Polimorfismo de Nucleotídeo Único , Trypanosoma cruzi , Cardiomiopatia Chagásica/parasitologia , Classe Ib de Fosfatidilinositol 3-Quinase/metabolismo , Variação Genética , Genótipo , Coração/parasitologia , Interações Hospedeiro-Parasita , Humanos , Doenças Negligenciadas/genética , Doenças Negligenciadas/parasitologia , Transdução de Sinais
10.
Curr Opin Microbiol ; 52: 64-69, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31212190

RESUMO

In the last 30 years, significant advances in genetic manipulation tools along with complete genome and transcriptome sequencing have advanced our understanding of the biology of Leishmania parasites and their interplay with the sand fly and mammalian hosts. High-throughput sequencing in association with CRISPR/Cas9 have prepared the ground for significant advances. Given the richness of the progress made over the last decade, in this article, we focused on the most recent contributions of genome-wide and transcriptome analyses of Leishmania spp., which permit the comparison of life cycle stages, the evaluation of different strains and species in their natural niches and in the field and the simultaneously comparison of the gene expression profiles of parasites and hosts.


Assuntos
Perfilação da Expressão Gênica , Genoma de Protozoário , Interações Hospedeiro-Parasita/genética , Leishmania/genética , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Estágios do Ciclo de Vida , Fenótipo , Psychodidae/parasitologia , Transcriptoma , Sequenciamento Completo do Genoma
11.
RNA Biol ; 16(5): 639-660, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30689499

RESUMO

Leishmaniasis is a worldwide public health problem caused by protozoan parasites of the genus Leishmania. Leishmania braziliensis is the most important species responsible for tegumentary leishmaniases in Brazil. An understanding of the molecular mechanisms underlying the success of this parasite is urgently needed. An in-depth study on the modulation of gene expression across the life cycle stages of L. braziliensis covering coding and noncoding RNAs (ncRNAs) was missing and is presented herein. Analyses of differentially expressed (DE) genes revealed that most prominent differences were observed between the transcriptomes of insect and mammalian proliferative forms (6,576 genes). Gene ontology (GO) analysis indicated stage-specific enriched biological processes. A computational pipeline and 5 ncRNA predictors allowed the identification of 11,372 putative ncRNAs. Most of the DE ncRNAs were found between the transcriptomes of insect and mammalian proliferative stages (38%). Of the DE ncRNAs, 295 were DE in all three stages and displayed a wide range of lengths, chromosomal distributions and locations; many of them had a distinct expression profile compared to that of their protein-coding neighbors. Thirty-five putative ncRNAs were submitted to northern blotting analysis, and one or more hybridization-positive signals were observed in 22 of these ncRNAs. This work presents an overview of the L. braziliensis transcriptome and its adjustments throughout development. In addition to determining the general features of the transcriptome at each life stage and the profile of protein-coding transcripts, we identified and characterized a variety of noncoding transcripts. The novel putative ncRNAs uncovered in L. braziliensis might be regulatory elements to be further investigated.


Assuntos
Perfilação da Expressão Gênica/métodos , Leishmania braziliensis/crescimento & desenvolvimento , RNA de Protozoário/genética , Análise de Sequência de RNA/métodos , Animais , Brasil , Biologia Computacional/métodos , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Humanos , Insetos/parasitologia , Leishmania braziliensis/genética , Mamíferos/parasitologia , RNA não Traduzido/genética
12.
Mol Biochem Parasitol ; 214: 69-74, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28385563

RESUMO

Non-coding RNAs (ncRNAs) are regulatory elements present in a wide range of organisms, including trypanosomatids. ncRNAs transcribed from the untranslated regions (UTRs) of coding genes have been described in the transcriptomes of several eukaryotes, including Trypanosoma brucei. To uncover novel putative ncRNAs in two Leishmania species, we examined a L. major cDNA library and a L. donovani non-polysomal RNA library. Using a combination of computational analysis and experimental approaches, we classified 26 putative ncRNA in L. major, of these, 5 arising from intergenic regions and 21 from untranslated regions. In L. donovani, we classified 37 putative ncRNAs, of these, 7 arising from intergenic regions, and 30 from UTRs. Our results suggest, for the first time, that UTR-transcripts may be a common feature in the eukaryote Leishmania similarly to those previously shown in T. brucei and other eukaryotes.


Assuntos
Leishmania donovani/genética , Leishmania major/genética , RNA não Traduzido/análise , RNA não Traduzido/genética , Regiões não Traduzidas , Biologia Computacional , Perfilação da Expressão Gênica , Biblioteca Gênica
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