RESUMO
BACKGROUND: Cerebral malaria (CM), a reversible encephalopathy affecting young children, is a medical emergency requiring rapid clinical assessment and treatment. However, understanding of the genes/proteins and the biological pathways involved in the disease outcome is still limited. METHODS: We have performed a whole transcriptomic analysis of blood samples from Malian children with CM or uncomplicated malaria (UM). Hierarchical clustering and pathway, network, and upstream regulator analyses were performed to explore differentially expressed genes (DEGs). We validated gene expression for 8 genes using real-time quantitative PCR (RT-qPCR). Plasma levels were measured for IP-10/CXCL10 and IL-18. RESULTS: A blood RNA signature including 538 DEGs (â£FC | ≥2.0, adjusted P value ≤ 0.01) allowed to discriminate between CM and UM. Ingenuity Pathway Analysis (IPA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed novel genes and biological pathways related to immune/inflammatory responses, erythrocyte alteration, and neurodegenerative disorders. Gene expressions of CXCL10, IL12RB2, IL18BP, IL2RA, AXIN2, and NET were significantly lower in CM whereas ARG1 and SLC6A9 were higher in CM compared to UM. Plasma protein levels of IP-10/CXCL10 were significantly lower in CM than in UM while levels of IL-18 were higher. Interestingly, among children with CM, those who died from a complication of malaria tended to have higher concentrations of IP-10/CXCL10 and IFN-γ than those who recovered. CONCLUSIONS: This study identified some new factors and mechanisms that play crucial roles in CM and characterized their respective biological pathways as well as some upstream regulators.
Assuntos
Encéfalo/metabolismo , Eritrócitos/metabolismo , Inflamação/sangue , Malária Cerebral/genética , Malária Cerebral/metabolismo , Transcriptoma/genética , Quimiocina CXCL10/sangue , Biologia Computacional/métodos , Humanos , Interleucina-18/sangue , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Cerebral malaria, a reversible encephalopathy affecting young children, is a medical emergency requiring urgent clinical assessment and treatment. We performed a whole-transcriptomic analysis of blood samples from Malian children with cerebral or uncomplicated malaria. We focused on transcripts from pathways for which dysfunction has been associated with neurodegenerative disorders. We found that SNCA, SIAH2, UBB, HSPA1A, TUBB2A, and PINK1 were upregulated (fold-increases, ≥2.6), whereas UBD and PSMC5 were downregulated (fold-decreases, ≤4.39) in children with cerebral malaria, compared with those with uncomplicated malaria. These findings provide the first evidence for pathogenic mechanisms common to human cerebral malaria and neurodegenerative disorders.
Assuntos
Malária Cerebral/genética , Malária Falciparum/genética , Doenças Neurodegenerativas/genética , ATPases Associadas a Diversas Atividades Celulares , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Criança , Pré-Escolar , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Proteínas com Domínio LIM/genética , Proteínas com Domínio LIM/metabolismo , Leucócitos Mononucleares/parasitologia , Malária Cerebral/diagnóstico , Malária Falciparum/diagnóstico , Masculino , Doenças Neurodegenerativas/diagnóstico , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Plasmodium falciparum , Estudos Prospectivos , Complexo de Endopeptidases do Proteassoma , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Reprodutibilidade dos Testes , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/genética , Ubiquitinas/metabolismo , Regulação para Cima , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismoRESUMO
Background: Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America and affects 10 million people worldwide. Approximately 12000 deaths attributable to Chagas disease occur annually due to chronic Chagas disease cardiomyopathy (CCC), an inflammatory cardiomyopathy presenting with heart failure and arrythmia; 30% of infected subjects develop CCC years after infection. Genetic mechanisms play a role in differential progression to CCC, but little is known about the role of epigenetic modifications in pathological gene expression patterns in CCC patients' myocardium. DNA methylation is the most common modification in the mammalian genome. Methods: We investigated the impact of genome-wide cardiac DNA methylation on global gene expression in myocardial samples from end-stage CCC patients, compared to control samples from organ donors. Results: In total, 4720 genes were differentially methylated between CCC patients and controls, of which 399 were also differentially expressed. Several of them were related to heart function or to the immune response and had methylation sites in their promoter region. Reporter gene and in silico transcription factor binding analyses indicated promoter methylation modified expression of key genes. Among those, we found potassium channel genes KCNA4 and KCNIP4, involved in electrical conduction and arrythmia, SMOC2, involved in matrix remodeling, as well as enkephalin and RUNX3, potentially involved in the increased T-helper 1 cytokine-mediated inflammatory damage in heart. Conclusions: Results support that DNA methylation plays a role in the regulation of expression of pathogenically relevant genes in CCC myocardium, and identify novel potential disease pathways and therapeutic targets in CCC.
Assuntos
Cardiomiopatia Chagásica/genética , Doença de Chagas/genética , Metilação de DNA/genética , Adolescente , Adulto , Idoso , Cardiomiopatia Chagásica/parasitologia , Doença de Chagas/parasitologia , Doença Crônica , Impressões Digitais de DNA/métodos , Feminino , Expressão Gênica/genética , Coração/parasitologia , Humanos , Inflamação/genética , Inflamação/parasitologia , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Canais de Potássio/genética , Regiões Promotoras Genéticas/genética , Trypanosoma cruzi/patogenicidade , Adulto JovemRESUMO
The outcome of Leishmania infections varies substantially, depending on the host and the parasite strain; infection may be asymptomatic or cause mild or severe skin ulcers (cutaneous leishmaniasis [CL]), limited or disseminated lesions, or lethal visceral disease. We previously reported an association between IL-2R mutations and susceptibility to visceral leishmaniasis in children infected with Leishmania donovani. In the present study, we evaluated the possible role of IL-2 signaling in human CL. We first showed that the transcripts of several genes of the IL-2 pathway were abundant in skin lesions caused by Leishmania braziliensis. We then carried out a genetic analysis, focusing on major genes of the IL-2 pathway. We used a family-based approach and found that polymorphisms of several genes appeared to be associated with CL in a Brazilian population. Moreover, two polymorphisms of the IL2RA gene were significantly and independently associated with CL. We confirmed this result in a second Brazilian sample (also exposed to L. braziliensis) and in Iranians infected with Leishmania tropica: IL2RA rs10905669 T (Pcombined = 6 × 10(-7)) and IL2RA rs706778 T (Pcombined = 2 × 10(-9)) were associated with greater susceptibility to lesion development. These alleles were also correlated with a poor IFN-γ response and poor FOXP3(+) regulatory T cell activation. Thus, IL-2 plays a crucial role in protection against the cutaneous ulcers caused by Leishmania, and the IL-2 pathway is a potential target for strategies aiming to control Leishmania-related diseases.
Assuntos
Subunidade alfa de Receptor de Interleucina-2/imunologia , Interleucina-2/imunologia , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/imunologia , Polimorfismo de Nucleotídeo Único/imunologia , Adolescente , Adulto , Criança , Feminino , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Frequência do Gene , Predisposição Genética para Doença/genética , Genótipo , Interações Hospedeiro-Parasita/imunologia , Humanos , Interferon gama/imunologia , Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/genética , Leishmania braziliensis/fisiologia , Leishmaniose Cutânea/genética , Leishmaniose Cutânea/parasitologia , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único/genética , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Adulto JovemRESUMO
Long noncoding RNAs (lncRNAs) modulate gene expression at the epigenetic, transcriptional, and posttranscriptional levels. Dysregulation of the lncRNA known as myocardial infarction-associated transcript (MIAT) has been associated with myocardial infarction. Chagas disease causes a severe inflammatory dilated chronic cardiomyopathy (CCC). We investigated the role of MIAT in CCC. A whole-transcriptome analysis of heart biopsy specimens and formalin-fixed, paraffin-embedded samples revealed that MIAT was overexpressed in patients with CCC, compared with subjects with noninflammatory dilated cardiomyopathy and controls. These results were confirmed in a mouse model. Results suggest that MIAT is a specific biomarker of CCC.
Assuntos
Doença de Chagas/complicações , Doença de Chagas/genética , Perfilação da Expressão Gênica , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/genética , RNA Longo não Codificante , Animais , Doença de Chagas/fisiopatologia , Feminino , Humanos , Masculino , Camundongos , Fatores de TranscriçãoRESUMO
Cerebral malaria (CM) is a neurological complication of infection with Plasmodium falciparum that is partly caused by cytokine-mediated inflammation. It is not known whether interleukin-17 (IL-17) cytokines, which regulate inflammation, control the development of CM. To evaluate the involvement of IL-17 cytokines in CM, we analyzed 46 common polymorphisms in IL17A, IL17F, and IL17RA (which encodes the common receptor chain of the members of the IL-17 family) in two independent African populations. A case-control study involving 115 Nigerian children with CM and 160 controls from the community (CC) showed that IL17F reference single nucleotide polymorphism (SNP) 6913472 (rs6913472) (P = 0.004; odds ratio [OR] = 3.12), IL17F rs4715291 (P = 0.004; OR = 2.82), IL17RA rs12159217 (P = 0.01; OR = 2.27), and IL17RA rs41396547 (P = 0.026; OR = 3.15) were independently associated with CM. A replication study was performed in 240 nuclear Malian family trios (two parents with one CM child). We replicated the association for 3 SNPs, IL17F rs6913472 (P = 0.03; OR = 1.39), IL17RA rs12159217 (P = 0.01; OR = 1.52), and IL17RA rs41396547 (P = 0.04; OR = 3.50). We also found that one additional SNP, IL17RA rs41433045, in linkage disequilibrium (LD) with rs41396547, was associated with CM in both Nigeria and Mali (P = 0.002; OR = 4.12 in the combined sample). We excluded the possibility that SNPs outside IL17F and IL17RA, in strong LD with the associated SNPs, could account for the observed associations. Furthermore, the results of a functional study indicated that the aggravating GA genotype of IL17F rs6913472 was associated with lower IL-17F concentrations. Our findings show for the first time that IL17F and IL17RA polymorphisms modulate susceptibility to CM and provide evidence that IL-17F protects against CM.
Assuntos
Interleucina-17/genética , Malária Cerebral/etnologia , Malária Cerebral/genética , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina-17/genética , Adolescente , África/epidemiologia , Criança , Pré-Escolar , Simulação por Computador , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genética Populacional , Genótipo , Humanos , Lactente , Interleucina-17/imunologia , Desequilíbrio de Ligação , Malária Cerebral/epidemiologia , Malária Cerebral/imunologia , Masculino , Receptores de Interleucina-17/imunologiaRESUMO
UNLABELLED: Interleukin (IL)-22 acts on epithelia, hepatocytes, and pancreatic cells and stimulates innate immunity, tissue protection, and repair. IL-22 may also cause inflammation and abnormal cell proliferation. The binding of IL-22 to its receptor is competed by IL-22 binding protein (IL-22BP), which may limit the deleterious effects of IL-22. The role of IL-22 and IL-22BP in chronic liver diseases is unknown. We addressed this question in individuals chronically infected with schistosomes or hepatitis C virus (HCV). We first demonstrate that schistosome eggs stimulate production of IL-22 transcripts and inhibit accumulation of IL22-BP transcripts in schistosome-infected mice, and that schistosome eggs selectively stimulate production of IL-22 in cultures of blood leukocytes from individuals chronically infected with Schistosoma japonicum. High IL-22 levels in cultures correlated with protection against hepatic fibrosis and portal hypertension. To test further the implication of IL-22/IL-22BP in hepatic disease, we analyzed common genetic variants of IL22RA2, which encodes IL-22BP, and found that the genotypes, AA, GG of rs6570136 (P = 0.003; odds ratio [OR] = 2), and CC, TT of rs2064501 (P = 0.01; OR = 2), were associated with severe fibrosis in Chinese infected with S. japonicum. We confirmed this result in Sudanese (rs6570136 GG [P = 0.0007; OR = 8.2], rs2064501 TT [P = 0.02; OR = 3.1]), and Brazilians (rs6570136 GG [P = 0.003; OR = 26], rs2064501 TC, TT (P = 0.03; OR = 11]) infected with S. mansoni. The aggravating genotypes were associated with high IL22RA2 transcripts levels. Furthermore, these same variants were also associated with HCV-induced fibrosis and cirrhosis (rs6570136 GG, GA [P = 0.007; OR = 1.7], rs2064501 TT, TC (P = 0.004; OR = 2.4]). CONCLUSIONS: These results provide strong evidence that IL-22 protects against and IL-22BP aggravates liver fibrosis and cirrhosis in humans with chronic liver infections. Thus, pharmacological modulation of IL-22 BP may be an effective strategy to limit cirrhosis.
Assuntos
Hepatite C Crônica/complicações , Interleucinas/fisiologia , Cirrose Hepática/etiologia , Receptores de Interleucina/fisiologia , Esquistossomose/complicações , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Interleucina 22RESUMO
We have previously found that children heterozygous for IL4 variable-number tandem repeat (VNTR) (rs8179190) or IL4-33 (rs2070874) variants were at risk for severe malaria (SM), whereas homozygous children were protected suggesting a complex genetic control. Hence, to dissect this complex genetic control of IL4 VNTR and IL4-33, we performed further investigation by conditional logistic regression analysis and found a strong interaction between both markers (p < 10(-6)). The best-fit model revealed three genotype combinations associated with different levels of SM risk. The highest risk (odds ratio (OR) = 4.8, 95% confidence interval (CI) = 2.0-11.5) was observed for subjects carrying at least one copy of both IL4-33 allele T and IL4 VNTR allele 1, who exhibited higher interleukin (IL)-4 plasma levels (p = 0.007). Children homozygous for IL4 VNTR allele 2 had a lower SM risk as well as lower IL-4 plasma levels. Our findings indicate that the genetic interaction between these two IL-4 variants is a key factor of SM susceptibility, probably because of its direct role in IL-4 regulation.
Assuntos
Predisposição Genética para Doença , Genótipo , Interleucina-4/genética , Malária/genética , Feminino , Estudos de Associação Genética , Genética Populacional , Humanos , Interleucina-4/sangue , Malária/sangue , Malária/patologia , Masculino , Mali , Repetições Minissatélites/genética , Polimorfismo de Nucleotídeo Único , Fatores de RiscoRESUMO
BACKGROUND: Chronic Chagas Disease cardiomyopathy (CCC), a life-threatening inflammatory dilated cardiomyopathy, affects 30% of the approximately 8 million patients infected by Trypanosoma cruzi, the rest of the infected subjects remaining asymptomatic (ASY). The Th1 T cell-rich myocarditis plays a pivotal role in CCC pathogenesis. Local expression of IL-18 in CCC myocardial tissue has recently been described. IL-18 could potentially amplify the process by inducing increased expression of IFN-γ which in turn can increase the production of IL-18, thereby creating a positive feedback mechanism. In order to assess the contribution of the IL-18 to susceptibility to Chronic Chagas Disease, we investigated the association between a single nucleotide polymorphism (SNP) located in the IL-18 gene with the risk of developing Chagas cardiomyopathy. METHODS AND RESULTS: We analyzed the rs2043055 marker in the IL18 gene in a cohort of Chagas disease cardiomyopathy patients (n=849) and asymptomatic subjects (n=202). We found a significant difference in genotype frequencies among moderate and severe CCC patients with ventricular dysfunction. CONCLUSIONS: Our analysis suggests that the IL18 rs2043055 polymorphism- or a SNP in tight linkage disequilibrium with it- may contribute to modulating the Chagas cardiomyopathy outcome.
Assuntos
Cardiomiopatia Chagásica/genética , Predisposição Genética para Doença , Interleucina-18/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Cardiomiopatia Chagásica/fisiopatologia , Doença Crônica , Estudos de Coortes , Feminino , Estudos de Associação Genética , Humanos , Masculino , Volume SistólicoRESUMO
Chagas disease, caused by the protozoan Trypanosoma cruzi, is an endemic parasitic disease of Latin America, affecting 7 million people. Although most patients are asymptomatic, 30% develop complications, including the often-fatal Chronic Chagasic Cardiomyopathy (CCC). Although previous studies have demonstrated some genetic deregulations associated with CCCs, the causes of their deregulations remain poorly described. Based on bulk RNA-seq and whole genome DNA methylation data, we investigated the genetic and epigenetic deregulations present in the moderate and severe stages of CCC. Analysis of heart tissue gene expression profile allowed us to identify 1407 differentially expressed transcripts (DEGs) specific from CCC patients. A tissue DNA methylation analysis done on the same tissue has permitted the identification of 92 regulatory Differentially Methylated Regions (DMR) localized in the promoter of DEGs. An in-depth study of the transcription factors binding sites (TFBS) in the DMRs corroborated the importance of TFBS's DNA methylation for gene expression in CCC myocardium. TBX21, RUNX3 and EBF1 are the transcription factors whose binding motif appears to be affected by DNA methylation in the largest number of genes. By combining both transcriptomic and methylomic analysis on heart tissue, and methylomic analysis on blood, 4 biological processes affected by severe CCC have been identified, including immune response, ion transport, cardiac muscle processes and nervous system. An additional study on blood methylation of moderate CCC samples put forward the importance of ion transport and nervous system in the development of the disease.
Assuntos
Cardiomiopatia Chagásica , Doença de Chagas , Trypanosoma cruzi , Doença de Chagas/genética , Epigênese Genética , Humanos , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: GATA1 is an essential transcription factor for both polyploidization and megakaryocyte (MK) differentiation. The polyploidization defect observed in GATA1 variant carriers is not well understood. OBJECTIVE: To extensively phenotype two pedigrees displaying different variants in the GATA1 gene and determine if GATA1 controls MYH10 expression levels, a key modulator of MK polyploidization. METHOD: A total of 146 unrelated propositi with constitutional thrombocytopenia were screened on a multigene panel. We described the genotype-phenotype correlation in GATA1 variant carriers and investigated the effect of these novel variants on MYH10 transcription using luciferase constructs. RESULTS: The clinical profile associated with the p.L268M variant localized in the C terminal zinc finger was unusual in that the patient displayed bleeding and severe platelet aggregation defects without early-onset thrombocytopenia. p.N206I localized in the N terminal zinc finger was associated, on the other hand, with severe thrombocytopenia (15G/L) in early life. High MYH10 levels were evidenced in platelets of GATA1 variant carriers. Analysis of MKs anti-GATA1 chromatin immunoprecipitation-sequencing data revealed two GATA1 binding sites, located in the 3' untranslated region and in intron 8 of the MYH10 gene. Luciferase reporter assays showed their respective role in the regulation of MYH10 gene expression. Both GATA1 variants significantly alter intron 8 driven MYH10 transcription. CONCLUSION: The discovery of an association between MYH10 and GATA1 is a novel one. Overall, this study suggests that impaired MYH10 silencing via an intronic regulatory element is the most likely cause of GATA1-related polyploidization defect.
Assuntos
Fator de Transcrição GATA1 , Megacariócitos , Cadeias Pesadas de Miosina/genética , Miosina não Muscular Tipo IIB/genética , Trombocitopenia , Plaquetas , Fator de Transcrição GATA1/genética , Inativação Gênica , Humanos , Trombocitopenia/genética , Trombopoese/genética , Fatores de TranscriçãoRESUMO
The role of the Th1 pathway in the pathogenesis of severe malaria is unclear. We recently reported that a polymorphism with increasing IFNG transcription is associated with protection against cerebral malaria (CM). Interleukin-12 is required for Th1 cell differentiation, which is characterized by the production of interferon-gamma. We investigated 21 markers in IL12-related genes, including IL12A and IL12B encoding the two IL-12 (IL12p70) subunits, IL12p35 and IL12p40. We performed a family-based association study using a total sample set of 240 nuclear families. The IL12Bpro polymorphism was associated with susceptibility to CM. The CTCTAA allele and the GC/CTCTAA genotype are over-transmitted to children with CM (P = 0.0002 and 0.00002, respectively). We estimated the odds ratio to be 2.11 for risk of CM in heterozygous children [(95% confidence interval, 1.49-2.99); P < 0.0001]. Although the CTCTAA allele had a dominant effect on CM susceptibility, this effect is much stronger in heterozygous children, consistent with the functional effects of this allele in a heterozygous form. Heterozygosity for this polymorphism has been associated with reduced expression of the gene encoding IL12p40 and a low level of IL12p70 production. These results, together with the findings from immunological studies of low interferon-gamma and IL-12 levels in CM, support a protective role for the Th1 pathway in CM.
Assuntos
Predisposição Genética para Doença , Subunidade p40 da Interleucina-12/genética , Malária Cerebral/genética , Regiões Promotoras Genéticas , Criança , Estudos de Coortes , Heterozigoto , Humanos , Subunidade p35 da Interleucina-12/genética , Razão de Chances , Polimorfismo Genético , Receptores de Interleucina-12/genética , Fator de Transcrição STAT4/genéticaRESUMO
BACKGROUND: Severe malaria (SM) due to Plasmodium falciparum causes millions of child deaths in sub-Saharan Africa. It comprises a variety of clinical disorders, including cerebral malaria (CM) and severe anemia (SA). In previous work, we have shown that interferon gamma and interleukin 12 protect against CM. Here, we investigated whether interleukin 4 (IL-4) aggravates the risk of severe disease. METHODS: We prospectively recruited children with CM (n = 240), SA (n = 101), and uncomplicated malaria (UM) (n = 42) in Bamako, Mali, and measured IL-4 production in plasma by enzyme-linked immunosorbent assay. We then assessed the influence of 11 polymorphisms on predisposition to SM by the family-based association test (FBAT). RESULTS: IL-4 concentrations were higher in children with CM than in children with UM during malaria (P = .003). FBAT analyses showed that the most significant association was between the IL4 variable-number tandem repeat (VNTR) 1/2 genotype and SM (P < .001); an association was also observed for IL4 -33 C/T, rs2243267 G/C, rs2243268 C/A, and rs2243282 C/A (P < .05). Interestingly, we found that the plasma concentration of IL-4 was higher in subjects with the IL4 VNTR 1/2 or 1/1 genotype than with the IL4 VNTR 2/2 genotype (P = .003). CONCLUSIONS: These results support the view that IL-4 may be a risk factor for SM. IL-4 may aggravate the disease by interfering with type 1 T helper cell differentiation or by promoting local inflammation at sites of parasite sequestration.
Assuntos
Interleucina-4/genética , Malária Cerebral/genética , Malária Falciparum/genética , Repetições Minissatélites/genética , Polimorfismo de Nucleotídeo Único/genética , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Interleucina-4/sangue , Malária Cerebral/imunologia , Malária Falciparum/imunologia , MasculinoRESUMO
Chronic Chagas disease cardiomyopathy (CCC), an especially aggressive inflammatory dilated cardiomyopathy caused by lifelong infection with the protozoan Trypanosoma cruzi, is a major cause of cardiomyopathy in Latin America. Although chronic myocarditis may play a major pathogenetic role, little is known about the molecular mechanisms responsible for its severity. The aim of this study is to study the genes and microRNAs expression in tissues and their connections in regards to the pathobiological processes. To do so, we integrated for the first time global microRNA and mRNA expression profiling from myocardial tissue of CCC patients employing pathways and network analyses. We observed an enrichment in biological processes and pathways associated with the immune response and metabolism. IFNγ, TNF and NFkB were the top upstream regulators. The intersections between differentially expressed microRNAs and differentially expressed target mRNAs showed an enrichment in biological processes such as Inflammation, inflammation, Th1/IFN-γ-inducible genes, fibrosis, hypertrophy, and mitochondrial/oxidative stress/antioxidant response. MicroRNAs also played a role in the regulation of gene expression involved in the key cardiomyopathy-related processes fibrosis, hypertrophy, myocarditis and arrhythmia. Significantly, a discrete number of differentially expressed microRNAs targeted a high number of differentially expressed mRNAs (>20) in multiple processes. Our results suggest that miRNAs orchestrate expression of multiple genes in the major pathophysiological processes in CCC heart tissue. This may have a bearing on pathogenesis, biomarkers and therapy.
Assuntos
Cardiomiopatia Chagásica/metabolismo , Cardiomiopatia Chagásica/patologia , Regulação da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Doença Crônica , Genoma Humano , Humanos , MicroRNAs/genética , Análise de Componente PrincipalRESUMO
[This corrects the article DOI: 10.3389/fimmu.2020.01386.].
RESUMO
Background: Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America. Thirty percent of infected individuals develop chronic Chagas cardiomyopathy (CCC), an inflammatory dilated cardiomyopathy that is the most important clinical consequence of T. cruzi infection, while the others remain asymptomatic (ASY). IFN-γ and IFN-γ-producing Th1-type T cells are increased in peripheral blood and CCC myocardium as compared to ASY patients, while the Th1-antagonizing cytokine IL-10 is more expressed in ASY patients. Importantly IFN-γ-producing Th1-type T cells are the most frequent cytokine-producing T cell subset in CCC myocardium, while expression of Th1-antagonizing cytokines IL-10 and IL-4 is unaltered. The control of IFN-γ production by Th1-type T cells may be a key event for progression toward CCC. A genetic component to disease progression was suggested by the familial aggregation of cases and the association of gene polymorphisms with CCC development. We here investigate the role of gene polymorphisms (SNPs) in several genes involved in the control of IFN-γ production and Th1 T cell differentiation in CCC development. Methods: We studied a Brazilian population including 315 CCC cases and 118 ASY subjects. We assessed 35 Tag SNPs designed to represent all the genetic information contained in the IL12B, IL10, IFNG, and IL4 genes. Results: We found 2 IL12 SNPs (rs2546893, rs919766) and a trend of association for a IL10 SNP (rs3024496) to be significantly associated with the ASY group. these associations were confirmed by multivariate analysis and allele tests. The rs919766C, 12rs2546893G, and rs3024496C alleles were associated to an increase risk to CCC development. Conclusions: Our data show that novel polymorphisms affecting IL12B and IL10, but not IFNG or IL4 genes play a role in genetic susceptibility to CCC development. This might indicate that the increased Th1 differentiation and IFN-γ production associated with CCC is genetically controlled.
Assuntos
Cardiomiopatia Chagásica/genética , Interleucina-10/genética , Subunidade p40 da Interleucina-12/genética , Diferenciação Celular , Cardiomiopatia Chagásica/imunologia , Doença Crônica , Progressão da Doença , Predisposição Genética para Doença , Interferon gama/biossíntese , Interferon gama/genética , Interleucina-4/genética , Polimorfismo de Nucleotídeo Único , Células Th1/imunologiaRESUMO
BACKGROUND: The population exposed to malaria within African cities has steadily increased. However, comprehensive data on life-threatening malaria features and risk factors in children from urban areas with seasonal malaria transmission, such as in Bamako (Mali), are lacking. METHODS: Children admitted to the Gabriel Touré Hospital in Bamako with severe malarial anemia (SMA) and/or cerebral malaria (CM) were prospectively included in the study. Indicators of either SMA or CM were analyzed using logistic regression; and death hazard ratios (HRs) were estimated through survival analysis. RESULTS: The study included 455 children: 66% presented with CM, 34% with SMA, 3% with hypoglycemia (HG); 5% with dehydration; 17% with respiratory distress (RD); 25% with splenomegaly; and 92% with hepatomegaly. The children with CM were older than those with SMA. CM was more often associated with dehydration, HG, and RD, whereas SMA was more often associated with splenomegaly. The overall case fatality rate was 16%, and 94% of the children who died had CM. HG [HR: 2.37; 95% confidence interval (CI): 1.04-5.39; P = 0.040], RD (HR: 4.23; 95% CI: 2.46-7.30; P < 10(-6)) and a deep coma with a Blantyre score of less than 3 (HR: 6.78, 95% CI: 2.43-18.91; P < 10(-3)), were all independent predictors of death. CONCLUSIONS: These findings delineate the patterns of severe malaria in children in a West African mesoendemic urban setting. They validate practicable prognostic indicators of life-threatening malaria for use in the limited facilities available in African health centers and provide a frame of reference for further research addressing life-threatening malaria in this setting.
Assuntos
Anemia/parasitologia , Malária Cerebral/epidemiologia , Adolescente , Criança , Pré-Escolar , Doenças Endêmicas , Feminino , Humanos , Lactente , Recém-Nascido , Malária Cerebral/mortalidade , Masculino , Mali/epidemiologia , Estudos Prospectivos , Fatores de Risco , Estações do Ano , População UrbanaRESUMO
MicroRNAs (miRNAs) are short, non-coding RNAs that repress the translation of target gene transcripts. They have been implicated in various activities such as cell proliferation, survival, differentiation, migration and metabolism. We report here the first known miRNome and transcriptome analysis of human livers displaying advanced fibrosis due to Schistosoma japonicum infection. We present evidence that hsa-miR-150-5p, hsa-miR-10a-5p, hsa-miR-199a-3p, hsa-miR-4521, hsa-miR-222/221, hsa-miR-663b and hsa-miR-143-3p (associated without correction) play an important role in hepatic fibrosis by acting on metabolism, organization of the extracellular matrix proteins, lipid mobilization and limitation of oxidative damage stress.
Assuntos
Cirrose Hepática/genética , MicroRNAs/fisiologia , Esquistossomose Japônica/patologia , Adulto , Animais , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Expressão Gênica , Humanos , Fígado/química , Fígado/patologia , Cirrose Hepática/etiologia , Cirrose Hepática/parasitologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Transcrição Reversa , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/complicações , Esquistossomose Japônica/genética , Regulação para Cima , Adulto JovemRESUMO
Chagas disease, caused by the parasite Trypanosoma cruzi, is endemic in Latin America. Its acute phase is associated with high parasitism, myocarditis and profound myocardial gene expression changes. A chronic phase ensues where 30% develop severe heart lesions. Mouse models of T. cruzi infection have been used to study heart damage in Chagas disease. The aim of this study was to provide an interactome between miRNAs and their targetome in Chagas heart disease by integrating gene and microRNA expression profiling data from hearts of T. cruzi infected mice. Gene expression profiling revealed enrichment in biological processes and pathways associated with immune response and metabolism. Pathways, functional and upstream regulator analysis of the intersections between predicted targets of differentially expressed microRNAs and differentially expressed mRNAs revealed enrichment in biological processes and pathways such as IFNγ, TNFα, NF-kB signaling signatures, CTL-mediated apoptosis, mitochondrial dysfunction, and Nrf2-modulated antioxidative responses. We also observed enrichment in other key heart disease-related processes like myocarditis, fibrosis, hypertrophy and arrhythmia. Our correlation study suggests that miRNAs may be implicated in the pathophysiological processes taking place the hearts of acutely T. cruzi-infected mice.