Paula Rocha Moreira

Federal University of Minas Gerais, Cidade de Minas, Minas Gerais, Brazil

Are you Paula Rocha Moreira?

Claim your profile

Publications (30)65.5 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Pattern recognition receptors, such as toll-like receptor 2 (TLR-2) and TLR-4, participate in the activation of immune cells by microorganisms in dental pulp. However, the expression levels of pattern recognition receptors can be modulated by epigenetic factors, especially DNA methylation. In this study, the methylation status of the TLR-2 and CD14 (TLR4 co-receptor) genes in healthy and inflamed human dental pulp was examined. The Methyl-Profiler DNA Methylation qPCR Assay was used to verify the DNA methylation patterns. No differences in the methylation patterns were observed between the 2 groups. Most DNA was unmethylated in both groups. The hypomethylation of TLR2 and CD14 genes is a usual feature in human dental pulp.
    Journal of endodontics 03/2014; 40(3):384-6. · 2.95 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Periodontitis is an inflammatory disorder characterized by interactions between periodontal pathogens and host's immune response. Epigenetic may contribute to disease development and outcome by influencing the expression of genes involved in the immune response. It has been shown that Toll-like receptors (TLR) play an important role in the response to periodontopathic bacteria. The aim of study was to evaluate the methylation status and the expression of TLR2 gene in gingival samples from individuals with and without periodontitis. DNA was analyzed using the Methyl Profiler DNA Methylation qPCR assay. DNA methylation and transcript levels were evaluated by real-time polymerase chain reaction. The periodontitis group showed a hypermethylated profile and a low expression of gene. Positive correlation between the TLR2 methylation frequency and probing depth was observed. This study gives the first evidence of methylation frequency in inflamed periodontal tissues and of the possible participation of methylation in the development of periodontitis.
    Human immunology 06/2013; · 2.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: INTRODUCTION: Periodontal disease (PD) is one of the most common inflammatory diseases, affecting about 10 % of the world population. The establishment of PD is influenced by polymorphisms in genes involved with the inflammatory response. Signal Transducer and Activator of Transcription (STAT)-1 is a transcription factor that plays a key role in the intracellular signaling triggered by cytokines and, thus, its activation is critical in inflammatory diseases. AIM AND METHODS: We aim to evaluate the occurrence of association between STAT-1 (rs3771300) polymorphism and distinct clinical forms and severity of PD; we genotyped 180 subjects using realtime PCR. RESULTS AND CONCLUSION: We observed that the presence of the G allele for STAT-1 was associated with twice as high of a chance to develop aggressive periodontitis, and the most severe form of the disease.
    Agents and Actions 04/2013; · 1.59 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose:  Experimental data have demonstrated a relevant role for IL-6 in the modulation of acute ocular toxoplasmosis. Therefore, we aim to investigate the possible association between the IL-6 gene polymorphism at position -174 and toxoplasmic retinochoroiditis (TR) in humans. Methods:  Ninety-seven patients with diagnosed TR were recruited from the Uveitis Section, Federal University of Minas Gerais. For comparison, 83 healthy blood donors with positive serology for toxoplasmosis and without retinal signs of previous TR were included in the study. Genomic DNA was obtained from oral swabs of individuals and amplified using polymerase chain reaction (PCR) with specific primers flanking the locus -174 of IL-6 (-174G/C). PCR products were submitted to restriction endonuclease digestion and analysed by polyacrylamide gel electrophoresis to distinguish allele G and C of the IL-6 gene, allowing the detection of the polymorphism and determination of genotypes. Results:  There was a significant difference in the genotype (χ(2)  = 12.9, p = 0.001) and allele (χ(2)  = 6.62, p = 0.01) distribution between TR patients and control subjects. In a subgroup analysis, there was no significant difference in genotypes and allele frequencies regarding TR recurrence. Conclusions:  This study suggests that the genotypes related with a lower production of IL-6 may be associated with the occurrence of TR.
    Acta ophthalmologica 01/2013; · 2.44 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Periodontitis is considered an inflammatory disorder of bacterial etiology that results in periodontal tissue destruction, as a result of complex interactions between periodontal pathogens, host and immune response. Genetic and epigenetic mechanisms may modulate the individual response since it is able to influence the gene expression. The aim of this study was to evaluate the impact of -174 G/C polymorphism and the methylation status of the promoter region of IL-6 gene on the expression of IL-6 in gingival samples from individuals with chronic periodontitis. Gingival biopsies were collected from 21 patients with chronic periodontitis and 21 controls. Histologic sections stained by hematoxylin-eosin were used for histopathological evaluation. The IL-6 gene expression was assessed by quantitative real-time PCR. The polymorphism IL-6 -174C/G was studied by polymerase chain reaction (PCR) amplification and restriction endonuclease digestion (HspII). Methylation-specific polymerase chain reaction was used to verify the DNA methylation pattern. The number of inflammatory cells in tissue fragments from individuals with chronic periodontitis was higher than in the control group and the inflammatory infiltrate was predominantly mononuclear. The expression of IL-6 was higher in the group with periodontitis. In polymorphism assay, no statistical difference in the distribution of genotypes and alleles in both groups were observed. The most of samples were partially methylated. No difference was observed in methylation pattern from two different regions of the IL-6 gene among groups. The high expression of IL-6 is an important factor related to chronic periodontitis, but was not associated with methylation status or the -174 (G/C) genetic polymorphism, suggesting that other mechanisms are involved in this gene transcription regulation.
    Immunobiology 12/2012; · 2.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The IL23/Th17 axis plays an important role in the pathogenesis of cell-mediated tissue damage caused either by autoimmunity or immune responses against bacterial infection. Single nucleotide polymorphisms in the IL17A, IL17F and IL23R genes have been associated with several inflammatory diseases. However, these polymorphisms have not yet been studied in periodontitis. The aim of present study was to evaluate the expression of IL17A and occurrence of the IL17A (rs2275913), IL17F (rs763780) and IL23R (rs11209026) gene polymorphisms in different clinical forms or severity of periodontitis in a sample of Brazilian individuals. Peripheral blood was obtained from 30 non-smoker individuals and analyzed by flow cytometry to determine IL-17 expression. Genomic DNA was obtained from oral swabs in 180 individuals and analyzed by Real-Time PCR. The study group was composed by individuals without periodontitis (control), with aggressive periodontitis (AP) and with chronic periodontitis (CP). Higher frequency of IL17A+CD4+Tcells was observed in control group. The A+ genotype from IL17A (rs2275913) was associated with lack of disease. No association was found considering the IL17F and IL23R polymorphisms. Our data suggest that IL17A and the presence of IL17A (rs2275913) A allele are associated with the absence of periodontal disease.
    Human immunology 11/2012; · 2.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: DNA methylation is characterized by the addition of methyl groups in cytosines within CpG islands. Unmethylated CpGs are related to transcriptionally active structure, whereas methylated CpG recruits methyl-binding proteins that promote chromatin compaction. DNA methylation can influence the expression of several genes and may play a role in the pathogenesis of inflammatory diseases such as periodontitis. Objective: the present study evaluated the methylation status of CD14 and TLR2 genes in gingival tissues from subjects without periodontitis and individuals with chronic periodontitis. Method: A total 22 gingival tissue samples from non-smokers individuals were included in this study. DNA was extracted and analyzed using the Methyl Profiler DNA Methylation qPCR assay. This method is based on the digestion of DNA by methylation-sensitive and methylation-dependent restriction enzymes. Histological sections stained by hematoxylin-eosin were used for histopathological evaluation of samples. Result: 10-20% of hypermethylation was detected in samples evaluated for CD14 gene in both the groups. Only the control group showed positivity for intermediate methylation with range of 49.42% to 91.87%. Considering the TLR-2 gene, high percentages of hypermethylation were found in control group and levels of intermediate methylation were similar between the groups. Conclusion: Further studies are needed to determine the functional relevance of these alterations.
    IADR General Session 2012; 06/2012
  • [Show abstract] [Hide abstract]
    ABSTRACT: DNA methylation is characterized by the addition of methyl groups in cytosines within CpG islands. Unmethylated CpGs are related to transcriptionally active structure, whereas methylated CpG recruits methyl-binding proteins that promote chromatin compaction. DNA methylation can influence the expression of cytokines and affect the development of periodontal disease. The purpose of the present study was to evaluate the methylation status of the interferon gamma (IFN-γ) and interleukin-10 (IL-10) genes in periodontal tissues. Methylation-specific polymerase chain reaction (MSP) and DNA sequencing analysis were used to verify the DNA methylation status of the IFN-γ and IL-10 genes, respectively, in samples from subjects without periodontitis and individuals with chronic periodontitis. Histological sections stained by hematoxylin-eosin were used for histopathological evaluation of samples. The methylation status of the IFN-γ and IL-10 genes was similar among the groups. Most of the samples were positive for IFN-γ methylation. Only 11% of the periodontitis group showed unmethylated DNA. Considering the IL-10 gene, no unmethylated sample was observed. The profile of total or partial methylation was detected in CpGs evaluated. The results showed evidence that methylation of IFN-γ and IL-10 genes is a usual feature on periodontal tissues. Further studies are needed to determine the functional relevance of these alterations.
    Immunobiology 08/2011; 216(8):936-41. · 2.81 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Odontogenic myxoma (OM) is an ectomesenchymal benign odontogenic tumor characterized by spindle or stellate-shaped cells embedded in an abundant myxoid or mucoid extracellular matrix. DNA methylation is characterized by the addition of methyl groups in cytosines within CpG islands in the promoter gene. DNA methylation can decrease the expression of tumor suppressor genes and contribute to the development of neoplastic lesions. The aim of study was to evaluate the methylation pattern of the tumor suppressor genes P16 (CDKN2A), P21 (CDKN1A), P27 (CDKN1B), P53 (TP53) and RB1 in OM and dental pulp. Methylation was evaluated using methylation-specific polymerase chain reaction (PCR). The transcription was studied in some cases by using reverse transcription quantitative PCR. A higher frequency of unmethylated P27, P53, and RB1 samples was observed in the OM when compared with the dental pulp. OM expressed mRNA of all the genes evaluated. Considering all the samples together, the expression of Rb was higher in the unmethylated samples compared with the partially methylated samples. This investigation revealed hypomethylation of the genes P27, P53, and RB1 in OM. In addition, methylation of tumor suppressor genes was found to be an usual event in normal dental pulp.
    Brazilian dental journal 01/2011; 22(5):422-7.
  • Paula Rocha Moreira
    Brazilian Dental Journal 12/2010; 22(5).
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Toxoplasma gondii infection is an important cause of ocular disease in both immunocompromised and immunocompetent subjects. The pathogenesis of retinochoroidal lesion associated with this infection is not fully understood. In this review, the role of the immune system in the control of Toxoplasma infection, especially in the eye, is discussed.
    Arquivos brasileiros de oftalmologia 12/2010; 73(6):548-51.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Interleukin-6 (IL-6) may be involved in drug-induced gingival overgrowth (GO). The present study was conducted to assess the association between IL-6 (-174 G/C) gene polymorphism and GO in renal transplant recipients under cyclosporine (CsA), tacrolimus (Tcr), or sirolimus (Sir)-based regimens. Within an eligible population, 45 unrelated subjects were selected for each CsA, Tcr, and Sir group, totaling a sample of 135 subjects. GO was visually assessed and subjects were assigned as controls (non-responders) or cases (responders) in a post hoc definition. IL-6 gene polymorphism was assessed using the polymerase chain reaction amplification and digestion. The distribution of genotypes and allele frequencies in responders and non-responders were compared using the Chi-squared test. The number of responders was 27 (60.0%), 13 (28.9%), and 7 (15.6%) in the CsA, Tcr, and Sir groups, respectively. No differences could be observed at frequencies of -174GG, -174CG, and -174CC genotypes when comparing responders to non-responders in the CsA, Tcr, and Sir groups. Similar to genotypes, allele frequencies showed no differences between responders and non-responders in all groups. No association between IL-6 (-174 G/C) gene polymorphism and gingival overgrowth was observed in renal transplant recipients under CsA, Tcr, or Sir-based immunosuppressive maintenance regimens.
    Archives of oral biology 07/2010; 55(7):494-501. · 1.65 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: De novo DNA methylation is a relevant epigenetic mechanism, which represses gene transcription and commonly inactivates tumor suppressor genes in carcinogenesis. A single nucleotide polymorphism of DNMT3B, C46359T (-149C-->T) was reported to modulate individual's susceptibility to cancer. We investigated the role of this polymorphic variant regarding the methylation status of the p16CDKN2A gene in young and older patients with head and neck squamous cell carcinoma (HNCC) matched by the TNM staging system, together with its impact on patients survival. The results showed that the presence of the allele T of the polymorphism DNMT3B (-149C-->T) was associated with advanced TNM staging and smoking habit, but no association was found between this polymorphisms and DNMT3B immunostaining. While p16CDKN2A methylation was significantly associated with smoking habit in older patients, this parameter was associated with family history of cancer in young patients. Moreover, in older patients the absence of p16CDKN2A promoter methylation had a negative impact on survival. In conclusion, nucleotide polymorphism of DNMT3B is not associated with methylation of p16CDKN2A gene in HNSCC. The association of p16CDKN2A gene methylation with smoking, family history of cancer and survival is dependent on age.
    International Journal of Oncology 07/2010; 37(1):167-76. · 2.66 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: DNA methylation is characterized by the addition of methyl groups in cytosines within cytosine-phosphate-guanine (CpG) islands. Unmethylated islands are related with transcriptionally active structure, whereas methylated DNA recruits methyl-binding proteins that promotes chromatin compaction. Although epigenetic events can influence the expression of cytokines, such events have not been investigated in dental pulp yet. The purpose of the present study was to evaluate the methylation status of the interferon gamma (IFN-gamma) gene in human dental pulp affected by inflammation compared with pulp tissue of impacted molar teeth and to verify the impact of methylation status in the expression pattern of the gene. Methylation-specific polymerase chain reaction (MSP) was used to verify the DNA methylation status of the IFN-gamma gene in 16 human dental pulps affected by inflammation and in 16 pulp samples of impacted molar teeth. Histologic sections stained by hematoxylin-eosin were used for histopathological evaluation, and the expression of IFN-gamma was assessed by quantitative real-time PCR (qPCR). Although total methylation was observed in 43.75% of the samples of normal dental pulp tissues, partial methylation or unmethylation was found in 93.75% of the samples of inflamed pulp tissues. All the samples with total methylation in MSP showed no transcription of IFN-gamma. The qPCR results showed expression of IFN-gamma in 5 of 10 samples with partial methylation. The present study gives the first evidence of the possible participation of epigenetic events in the development of dental pulp inflammation.
    Journal of endodontics 04/2010; 36(4):642-6. · 2.95 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The benign epithelial odontogenic tumours constitute a group of lesions derived from epithelial elements of the tooth-forming apparatus. This group includes lesions of different biological behaviour, such as ameloblastoma, calcifying cystic odontogenic tumour (CCOT) and adenomatoid odontogenic tumour (AOT). The pathogenesis of these neoplasms remains uncertain and the occurrence of methylation in cell-cycle related genes may be involved in their development. The aim of this study was to investigate the methylation status of P16, P21, P27, P53 and RB1 genes in epithelial odontogenic tumours. Methylation-specific polymerase chain reaction (MSP) was used to evaluate the presence of methylation in 13 samples of ameloblastoma, six samples of CCOT, three samples of AOT and 14 samples of dental follicles, included as control. Our results showed a distinct methylation profile in each group. In ameloblastoma, the highest methylated genes were P16 and P21, while in CCOT the P21 and RB1 genes were the most commonly methylated genes. Only the P16 and P21 genes were methylated in the AOT samples. In the dental follicle samples, P16, P27 and RB1 genes were commonly methylated. A high percentage of the odontogenic tumours analysed showed methylation of the P21 gene, in contrast to dental follicles. Epithelial odontogenic tumours show a distinct methylation profile in cell-cycle associated genes. In addition to this, the current findings show that epigenetic alterations are common events in epithelial odontogenic tumours.
    Archives of oral biology 09/2009; 54(10):893-7. · 1.65 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Over the past 10 years, a plethora of information concerning the influence of gene polymorphisms on cytokine expression has been made available in the literature. Significant contribution to this field has come from studies of oral diseases, one of the widest spread health problems in the world, affecting hundreds of millions worldwide. Here we will discuss the importance of studies of gene polymorphism towards the identification of susceptible groups or prognostic indicators of oral disease. Additionally, we will highlight the differences in data obtained from genetically diverse populations and review the application of cytokine gene polymorphisms studies in oral diseases in autoimmune processes and parasitic infections.
    Cytokine & growth factor reviews 07/2009; 20(3):223-32. · 6.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Periodontitis is a multifactorial infection characterized by inflammation and destruction of tooth supporting tissues, as a result of the response of a susceptible host to bacterial challenge. Studies have demonstrated that epigenetic events are able to influence the production of cytokines, contributing to the development of inflammatory diseases. Epigenetic events act through the remodeling of chromatin and can selectively activate or inactivate genes, determining their expression. The epigenetic process, by inducing a change in cytokine profile, may subsequently influence the pathogenesis and determine the outcome of many infectious diseases. These findings may have relevance for inflammatory diseases in which the expression of cytokines is unregulated. The purpose of this review is to show evidence that supports the hypothesis that epigenetic alterations, such as hyper and hypomethylation, of cytokine genes, could help to understand the mechanisms related to periodontal disease activity. Therefore, epigenetics may have future impact on diagnosis and/or therapeutics of periodontal disease.
    Agents and Actions 06/2009; 58(10):625-9. · 1.59 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Odontogenic keratocyst (OKC) is a benign neoplasm with an aggressive clinical behavior and a high recurrence rate. Although epigenetic alterations have been reported in different tumors, these events were not investigated in OKC yet. The aim of this study was to investigate the presence of methylation in P16, P21, P27, P53 and RB1 genes in OKC tumors. Methylation-specific polymerase chain reaction (MSP) was used to evaluate the presence of methylation in 10 samples of OKCs, 10 samples of dental follicles and six samples of normal mucosa. The methylation status of the P16 gene was similar among the three groups. In P21 gene, 30% of OKCs were methylated while no methylation could be detected in the other groups. High frequency of P27 methylation (90%) was observed in dental follicles, however, some OKC lesions (10%) and normal mucosa samples (33%) were also methylated. Concerning the RB1 gene, positive results were detected only in dental follicles (40%). No positive result was observed considering P53 gene. Our data show methylation of the promoter of P21 gene in OKCs. In addition, methylation of the P27 and RB1 genes are commonly found in dental follicles. Further studies are necessary to determine the functional relevance of these alterations.
    Journal of Oral Pathology and Medicine 02/2009; 38(1):99-103. · 2.06 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study was designed to determine whether the functional IL-10 gene polymorphism -1082G/A is associated with the development of cardiomyopathy in individuals infected with Trypanosoma cruzi and whether interleukin (IL)-10 expression can be correlated with patients' cardiac function. Our results demonstrated that the polymorphic allele, which correlates with lower expression of IL-10, was associated with the development of Chagas disease cardiomyopathy. Accordingly, correlative analysis showed that low IL-10 expression was associated with worse cardiac function, as determined by left-ventricular ejection fraction values. Therefore, the IL-10 gene polymorphism and IL-10 expression are important in determining susceptibility to chagasic cardiomyopathy.
    The Journal of Infectious Diseases 01/2009; 199(3):451-4. · 5.85 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: IL-10 and TNF-alpha are cytokines that have complex and opposing roles in the inflammatory responses. G/A polymorphisms at position -1082 of IL10 and -308 of TNFA genes have been reported to influence the expression of IL-10 and TNF-alpha, respectively. The aim of this study was to investigate the association between the IL10 (-1082) and TNFA (- 308) gene polymorphisms with different clinical forms or severity of periodontitis in a sample of Brazilian individuals. DNA was obtained from oral swabs of 165 Brazilian individuals, which were divided into three groups: individuals with chronic periodontitis, aggressive periodontitis and individuals without clinical evidence of periodontitis. Evaluation of IL10 and TNFA polymorphisms was performed by RFLP analysis. Statistical analysis of data was performed using the chi(2) likelihood ratio and Fisher;s exact test. No significant differences in the genotype and allele distribution of either IL10 or TNFA were observed among individuals with different clinical forms or with different degrees of severity of periodontitis. Moreover, combined analysis of IL10 and TNFA polymorphisms did not show any association with periodontal status. As conclusion, the IL10 and TNFA gene promoter polymorphisms investigated are not associated with different clinical forms of periodontitis or with severity of the disease in the Brazilian population polymorphisms.
    The Open Dentistry Journal 01/2009; 3:184-90.

Publication Stats

257 Citations
65.50 Total Impact Points

Institutions

  • 2000–2014
    • Federal University of Minas Gerais
      • • Institute of Biological Sciences
      • • Faculdade de Odontologia
      Cidade de Minas, Minas Gerais, Brazil
  • 2008
    • Unimed Belo Horizonte
      Cidade de Minas, Minas Gerais, Brazil