Petra Borilova Linhartova

IL1 gene polymorphisms in relation to external apical root resorption concurrent with orthodontia

OBJECTIVE External apical root resorption (EARR) is permanent shortening of the end of the tooth root. It is a common clinical complication of orthodontic treatment. Polymorphisms in the interleukin 1 (IL1) gene cluster have been related to an increased EARR risk. The aim of this study was to analyze possible associations of IL1 gene variants with EARR in Czech population. SUBJECTS AND METHODS In this case-control study, 32 patients with EARR (age 15.0 ± 4.1 years) and 74 controls (age 15.2 ± 5.3 years) were genotyped using PCR-based methods for IL1A (-889C/T), IL1B (+3953C/T), and IL1RN [IL1 receptor antagonist, variable number tandem repeat (VNTR)] gene polymorphisms. RESULTS While no statistical significant differences in the IL1A and IL1B genotype, allele and reconstructed IL1 haplotype frequencies between patients with EARR and controls were found, marginally significant differences were observed in the frequencies of IL1RN variant (P = 0.05 for *22 genotype and P = 0.06 for a short (2) allele). In addition, significant associations between IL1RN*12, *22 genotypes and the short (2) allele and EARR were identified in the subgroup of girls (P = 0.04 and P = 0.02, P = 0.02). CONCLUSIONS Although no significant role of IL1A (-889C/T) and IL1B (+3953C/T) variants in EARR was confirmed, IL1RN VNTR may be associated with EARR, especially in girls.

Haplotype analysis of interleukin-8 gene polymorphisms in chronic and aggressive periodontitis.

Objectives. Periodontitis is an inflammatory disease characterized by connective tissue loss and alveolar bone destruction. Interleukin-8 (IL8) is important in the regulation of the immune response. The aim of this study was to analyze four polymorphisms in the IL8 gene in relation to chronic (CP) and aggressive (AgP) periodontitis. Methods. A total of 492 unrelated subjects were included in this case-control association study. Genomic DNA of 278 patients with CP, 58 patients with AgP, and 156 controls were genotyped, using the 5′ nuclease TaqMan assay, for IL8 (rs4073, rs2227307, rs2227306, and rs2227532) gene polymorphisms. Subgingival bacterial colonization was investigated by the DNA-microarray detection kit in a subgroup of subjects (N = 247). Results. Allele and genotype frequencies of all investigated IL8 polymorphisms were not significantly different between the subjects with CP and/or AgP and controls (P > 0.05). Nevertheless, the A(−251)/T(+396)/T(+781) and T(−251)/G(+396)/C(+781) haplotypes were significantly less frequent in patients with CP (2.0% versus 5.1%, P < 0.02, OR = 0.34, 95% CI: 0.15–0.78, resp., 2.0% versus 4.5%, P < 0.05, OR = 0.41, 95% CI: 0.18–0.97) than in controls. Conclusions. Although none of the investigated SNPs in the IL8 gene was individually associated with periodontitis, some haplotypes can be protective against CP in the Czech population.

Interleukin-17A Gene Variability in Patients with Type 1 Diabetes Mellitus and Chronic Periodontitis: Its Correlation with IL-17 Levels and the Occurrence of Periodontopathic Bacteria

Interleukin-17 contributes to the pathogenesis of type 1 diabetes mellitus (T1DM) and chronic periodontitis (CP). We analyzed IL-17A −197A/G and IL-17F +7488C/T polymorphisms in T1DM and CP and determined their associations with IL-17 production and occurrence of periopathogens. Totally 154 controls, 125 T1DM, and 244 CP patients were genotyped using 5′ nuclease TaqMan® assays. Bacterial colonization was investigated by a DNA-microarray kit. Production of IL-17 after in vitro stimulation of mononuclear cells by mitogens and bacteria was examined by the Luminex system. Although no differences in the allele/genotype frequencies between patients with CP and T1DM + CP were found, the IL-17A −197 A allele increased the risk of T1DM (P < 0.05). Levels of HbA1c were significantly elevated in carriers of the A allele in T1DM patients (P < 0.05). Production of IL-17 by mononuclear cells of CP patients (unstimulated/stimulated by Porphyromonas gingivalis) was associated with IL-17A A allele (P < 0.05). IL-17A polymorphism increased the number of Tannerella forsythia and Treponema denticola in patients with CP and T1DM + CP, respectively (P < 0.05). IL-17A gene variability may influence control of T1DM and the “red complex” bacteria occurrence in patients with CP and T1DM + CP. Our findings demonstrated the functional relevance of the IL-17A polymorphism with higher IL-17 secretion in individuals with A allele.

Apolipoprotein E gene polymorphisms in relation to chronic periodontitis, periodontopathic bacteria, and lipid levels

OBJECTIVE Inflammatory periodontal diseases may be associated with common systemic conditions and, as recently described, alterations in lipid levels in the blood. The aim of this study was to determine the possible effects of apolipoprotein E (ApoE) genotypes on the lipid levels in healthy people and patients with chronic periodontitis (CP) in relation to periodontopathic bacteria. DESIGN This case-control study comprised 469 unrelated subjects. The genomic DNA of 294 patients with CP and 175 healthy/non-periodontitis controls were genotyped, using the real-time polymerase chain reaction (RT-PCR) method, for ApoE (rs429358 and rs7412) gene polymorphisms. Subgingival bacterial colonization was investigated by the DNA microarray using a periodontal pathogen detection kit and lipid levels were measured in a subgroup of subjects (N = 275). RESULTS There was no evidence for a significant association between ApoE gene polymorphisms and CP (P > 0.05). Patients with CP had increased levels of total cholesterol and low-density lipoprotein (LDL) compared to controls (P< 0.05); however, no significant difference was found for triglyceride and high-density lipoprotein (HDL) levels. ApoE gene variability influenced LDL levels marginally (P = 0.08) but it did not modify total cholesterol, triglyceride, and HDL levels or the occurrence of periodontal pathogens in subgingival pockets.(23) CONCLUSIONS: In the Czech population studied, ApoE genetic variations were not associated with susceptibility to CP or the presence of periodontopathic bacteria.

Haplotypes of the IL-1 gene cluster are associated with gastroesophageal reflux disease and Barrett’s esophagus

OBJECTIVES Gastroesophageal reflux (GERD) is a one of the major public health problem that can lead to reflux esophagitis (RE), Barretts esophagus (BE), and esophageal adenocarcinoma (EAC). The aim of our study was to determine the impact of IL-1 gene polymorphisms on the development of GERD, RE and BE. METHODS Three hundred and thirty-three Czech patients with gastroesophageal reflux and 165 healthy controls were included in this case-control study. Four polymorphisms in the genes of the IL-1 cluster [IL-1A(-889C/T), IL-1B(-511C/T), IL-1B(+3953C/T), and IL-1RN(VNTR)] were analyzed. RESULTS Significant differences were found in IL-1RN 1/2 genotype between patients with GERD/RE and controls and in IL-1B+3953 T allele between patients with BE and healthy subjects. In addition, complex analysis revealed differences in IL-1 haplotype frequencies between the groups. Specifically, the haplotype TCCL was significantly more frequent (p = 0.016) in GERD patients than in controls and the haplotype CCCL more frequent (p = 0.008) in RE patients than in controls. However, in patients with BE, frequency of haplotype TCTL was lower (p = 0.05) and haplotypes CTCL and TCCL were higher (p = 0.03 and p = 0.02) in comparison with the controls. CONCLUSIONS Our results suggest that IL-1 haplotypes may be associated with susceptibility to GERD, RE and BE.

The Effect of IL-4 Gene Polymorphisms on Cytokine Production in Patients with Chronic Periodontitis and in Healthy Controls

Chronic periodontitis (CP) is an inflammatory disease of the teeth-supporting tissues in which genetic predisposition, dental plaque bacteria, and immune mechanisms all play important roles. The aim of this study was to evaluate the occurrence of IL-4 gene polymorphisms in chronic periodontitis and to investigate the association between polymorphisms and cytokines production after bacterial stimulation. Sixty-two subjects (47 CP patients and 15 healthy controls) with detected two polymorphisms in the IL-4 gene (-590C/T and intron 3 VNTR) were examined. Production of cytokines (IL-1α, IL-1β, IL-4, IL-5, IL-6, IL-10, IL-17, TNFα, INFγ, and VEGF) was studied after in vitro stimulation of isolated peripheral blood by mitogens (Pokeweed mitogen, Concanavalin A), dental plaque bacteria (Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis, and Prevotella intermedia), and Heat Shock Protein (HSP) 70 by the Luminex multiplex cytokine analysis system. The results were correlated with IL-4 genotypes in patients with CP and healthy controls. The mononuclear cells isolated from peripheral blood of CP patients with selected IL-4 polymorphisms significantly altered the production of IFNγ, IL-10, IL-1β, IL-1α, TNFα, and IL-6 after stimulation by HSP 70 or selected bacteria (from P < 0.001 to P < 0.05). IL-4 gene polymorphisms may influence the function of mononuclear cells to produce not only interleukin-4 but also other cytokines, especially in patients with CP.

Interferon-γ +874A/T polymorphism in relation to generalized chronic periodontitis and the presence of periodontopathic bacteria

BACKGROUND Interferon gamma (IFN-γ) is one of the key regulatory cytokines that has a significant effect on immune responses. It may be important in the chronic inflammatory diseases such as periodontitis in which increased IFN-γ levels were found. The aim of this study was to analyze +874A/T polymorphism in the IFN-γ gene and its associations with the presence of periodontopathic bacteria and susceptibility to generalized chronic periodontitis (CP). METHODS A total of 498 unrelated Czech white subjects were included in the present study. Genomic DNA was obtained from the peripheral blood of 244 patients with CP and 254 healthy subjects. The IFN-γ +874A/T polymorphism was determined by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Subgingival bacterial colonization (A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia, T. denticola, P. micros, F. nucleatum in subgingival pockets) was investigated by the DNA-microarray based periodontal pathogen detection kit in a subgroup of subjects (N=110). RESULTS Our results showed no differences in the allele and genotype frequencies of the IFN-γ +874A/T polymorphism between patients with CP and controls (P>0.05). Although we found significant differences in the occurrence of periodontal bacteria between patients with CP and healthy controls (from P<0.00001 to P<0.05), no significant association between IFN-γ +874A/T polymorphism and periodontal pathogens was observed in any group. CONCLUSIONS In conclusion, these findings indicate that putative functional variant in the IFN-γ is not associated with susceptibility to chronic periodontitis or microbial composition in the Czech population.

Differences in Interleukin-8 Plasma Levels between Diabetic Patients and Healthy Individuals Independently on Their Periodontal Status

Chronic periodontitis (CP) and diabetes mellitus (DM) involve several aspects of immune functions, including neutrophil activity and cytokine biology. Considering the critical function of chemokine interleukin-8 (IL-8) in the inflammatory process, the aims of this study were to determine: (i) IL-8 plasma levels; (ii) IL-8 (−251A/T, rs4073) and its receptor 2 (CXCR2, +1208C/T, rs1126579) polymorphisms, and (iii) the presence of the selected periodontal bacteria in types 1 and 2 DM patients (T1DM and T2DM) and systemically healthy controls (HC) with known periodontal status. This case–control study comprises of 153 unrelated individuals: 36/44 patients suffering from T1DM+CP/T2DM+CP and 32/41 from HC+CP/non-periodontitis HC. Both the clinical and biochemical parameters were monitored. The genotypes were determined using qPCR, IL-8 plasma levels were measured using an ELISA kit. Subgingival bacterial colonization was analyzed with a DNA microarray detection kit. The IL-8 plasma levels differed significantly between non-periodontitis HC and T1DM+CP/T2DM+CP patients (P < 0.01). Even in HC+CP, IL-8 concentrations were significantly lower than in T1DM+CP/T2DM+CP patients (P ≤ 0.05). No significant associations between the IL-8 plasma levels and the studied IL-8 and CXCR2 polymorphisms or the occurrence of selected periodontal bacteria (P > 0.05) were found. CP does not influence the circulating IL-8 levels. Patients with T1DM+CP/T2DM+CP had higher circulating IL-8 levels than HC+CP/non-periodontitis HC.

Recurrent aphthous stomatitis and gene variability in selected interleukins: a case-control study

Genetic factors, especially those related to immune system functioning, have been intensively studied to determine their role in the development of recurrent aphthous stomatitis (RAS). The aim of the present study was to analyze gene variability in interleukin (IL)2, IL4 (and its receptor α, IL4Rα), IL10, and IL13, which were selected based on literature review and/or their functional relevance, in Czech patients with RAS and in healthy controls. In total, 252 subjects (178 controls and 74 patients with RAS) were enrolled in this case-control study, and their detailed anamnestic, clinical, and laboratory data were obtained. Nine polymorphisms in the genes encoding interleukins were determined using PCR techniques. There were no significant differences in allele or genotype frequencies of the IL2, IL4, IL4Rα, IL10, and IL13 polymorphisms rs2069762/rs2069763, rs2243250/rs79071878, rs1801275, rs1800896, and rs1800925, respectively, between controls and patients with RAS. The minority alleles rs1800871 and rs1800872, which encode variants of IL10, were associated with a statistically significantly higher risk of RAS, as confirmed by the results of genotype and haplotype analyses. We suggest that variability in the IL10 gene may play an important role in the development of RAS in the Czech population.