A functional interleukin-1 beta gene polymorphism is associated with chronic periodontitis in a sample of Brazilian individuals

BACKGROUND: Interleukin-1 beta (IL-1 beta) is a potent inflammatory mediator and an important polymorphism in the locus +3954 (C/T) of the human IL1 B gene has been shown to affect the levels of this cytokine. This functional polymorphism has been associated with the establishment of inflammatory diseases, including periodontal disease, in European, Asian and North American populations. OBJECTIVE: The aim of this study was to investigate the association between the IL1 B (+3954) gene polymorphism and the occurrence of different clinical forms of periodontitis in a sample of Brazilian individuals. METHODS: This study employed a cross-sectional design involving individuals from the State of Minas Gerais in the south-eastern region of Brazil. Genomic DNA was obtained from oral swabs of 129 individuals and amplified using the polymerase chain reaction (PCR) with specific primers flanking the locus +3954 of IL1 B. PCR products were submitted to restriction endonuclease digestion and analyzed by polyacrylamide gel electrophoresis, to distinguish alleles T and C of the IL1 B gene, allowing for the determination of the genotypes and detection of the polymorphism. RESULTS AND CONCLUSIONS: The chronic periodontitis group displayed a higher percentage of the T allele (28%) when compared to the aggressive periodontitis group (10.7%, chi(2)=5.24, p=0.02, OR=0.31, CI=0.11--0.88) and to control group (8.7%, chi(2)=7.11, p=0.007, OR=0.24, CI=0.08--0.73). Our data suggested that the polymorphism in the locus +3954 of IL1 B gene could be a risk factor for chronic periodontitis in a sample of Brazilian individuals.     

Interleukin-24, RANTES and CCR5 gene polymorphisms are not associated with chronic adult periodontitis

Background and Objective: Cytokines, such as interleukin‐10, and related genetic polymorphisms, have been implicated in the pathogenesis of chronic periodontitis. The aim of this study was to investigate a possible correlation between chronic periodontitis and genetic polymorphisms coding for two interleukin‐10 related chemokines [interleukin‐24 and regulated on activation, normal T cells expressed and secreted (RANTES)] as well as a RANTES receptor [CC chemokine receptor 5 (CCR5)]. Material and Methods: A single‐blind, two‐centre, case‐controlled study was carried out with test patients from the Clinic of Periodontics, Göteborg University, and from the Department of Periodontology, Glasgow University, and control subjects from the undergraduate clinics of both schools. Blood samples were collected from 106 patients (56 women and 50 men, mean age 51.7 yr) with generalized, severe chronic periodontitis and from 69 periodontally healthy subjects (37 women and 32 men, mean age 53.3 yr). The polymerase chain reaction (PCR) was used to identify the genetic coding for interleukin‐24, RANTES and CCR5. Genotype and allele frequencies were compared between the test and control groups using Fischer's exact test at the 5% level of significance. Results: There were no statistically significant differences between patients with chronic periodontitis and control subjects, regarding genotype distribution or allele frequency, irrespective of smoking status, in the combined Glasgow and Gothenburg cohort or in the specific location cohorts. The allele frequencies for healthy and control subjects for RANTES gave a p‐value of 0.80 (allele G was 58.8% in healthy subjects and and 54.4% in subjects with periodontitis), for interleukin‐24 the p‐value was 0.90 (allele T was 56.2% in healthy subjects and and 54.9% in subjects with periodontitis) and for CCR5 the p‐value was 0.90 (the wild‐type allele was 85% in healthy subjects and and 82.7% in subjects with periodontitis). Conclusion: The interleukin‐24, RANTES and CCR5 polymorphisms investigated are not associated with chronic periodontitis.     

Interleukin-4 gene polymorphisms in Japanese and Caucasian patients with aggressive periodontitis

OBJECTIVES: Recently, interleukin (IL) 4 gene polymorphisms have been analyzed in association with periodontitis. Genetic differences between Caucasian and Japanese patients with periodontitis have previously been detected. The aim of the present study was to analyze IL-4 genotypes in Caucasian and Japanese patients with aggressive periodontitis (AgP). MATERIAL AND METHODS: One hundred and twenty-four subjects were included in the study, 31 Japanese and 30 Caucasian patients with generalized AgP, plus 30 Japanese and 33 Caucasian healthy controls. IL-4 polymorphisms were determined by polymerase chain reaction. A logistic regression was used to investigate the possible association of the genotypes with the disease in both populations. Odds ratio (OR) estimates were analyzed for allele frequencies. RESULTS: No significant association of IL-4 polymorphisms with the risk of AgP was determined in either population. However, the allele frequencies showed different results between populations. The carriage of the polymorphism in intron 2 was higher in Caucasian patients compared with controls (OR: 2.0, 95% confidence interval: [1.0;4.2]. Furthermore, the frequency of the IL-4 promoter/intron 2 composite genotype (PP+/IP+) in patients and controls, respectively, was found to be approximately 25% and 60% higher in the Japanese population than in the Caucasian population. CONCLUSION: There was no evidence of an association of IL-4 genotypes and AgP in either population, although the frequencies of the IL-4 genotypes in the Japanese and the Caucasians were different.     

IL-6、IL-6R和IL-4多态性与上海地区汉族人群慢性牙周炎患者的关联研究

目的 研究IL-6、IL-6R和IL-4基因组单核苷酸多态性（single nucleotide polymorphisms,SNPs）与上海地区汉族人群慢性牙周炎患者的相关性。方法 应用TaqMan荧光实时定量PCR方法,对128例牙周正常者和198例中度以上慢性牙周炎患者的IL-6 -572G/C、IL-6R 48892A/C和 IL-4 -590C/T等3个单核苷酸多态性位点进行分析。应用SPSS 17.0软件包对数据进行χ2检验分析。结果 分析显示这3个位点的基因型频率与等位基因频率在牙周正常组和慢性牙周炎组间的分布差异均无显著性。结论 IL-6 -572G/C、IL-6R 48892A/C和 IL-4 -590C/T基因组单核苷酸多态性位点与上海地区汉族人群的慢性牙周炎易感性无显著相关性。     

Microbiological parameters associated with IL-1 gene polymorphisms in periodontitis patients

BACKGROUND, AIMS: Polymorphisms in the cluster of IL-1 genes have been significantly associated with the severity of adult periodontitis. The purpose of this study was to compare microbiological parameters in IL-1 genotype negative and positive adult subjects with a range of periodontitis severities. METHOD: The study included 108 subjects in good general health. Clinical parameters were recorded at 6 sites/tooth excluding 3rd molars and included: plaque accumulation, gingival erythema, bleeding on probing, suppuration, pocket depth and attachment level. Subgingival plaque samples were collected from the mesiobuccal surface of up to 28 teeth in each subject (mean 25.3) providing a total of 2736 samples. The levels of 40 subgingival taxa were determined in each sample using checkerboard DNA-DNA hybridization. Fingerstick blood samples were collected for IL-1A (+4845) and IL-1B (+3954) genotyping using PCR-based methods. RESULTS: The proportion of IL-1 genotype positive subjects that exhibited mean counts of specific subgingival species above selected thresholds was significantly higher than the proportion of genotype negative subjects. Prominent among species that were detected at higher levels in genotype positive subjects were members of the "red" and "orange" complexes and included: Bacteroides forsythus, Treponema denticola, the Fusobacterium nucleatum subspecies, Fusobacterium periodonticum, Campylobacter gracilis, Campylobacter showae and Streptococcus constellatus. Streptococcus intermedius, Streptococcus gordonii and 3 Capnocytophaga species were also detected more frequently at high numbers in genotype positive subjects. Significantly higher mean counts of B. forsythus, Porphyromonas gingivalis, T. denticola, the F. nucleatum subspecies, F. periodonticum, Campylobacter rectus, C. showae, Eubacterium nodatum, S. constellatus, S. gordonii, and S. intermedius were detected at periodontal pockets >6 mm in subjects who were genotype positive when compared with genotype negative subjects. The increase was due to increased numbers of cells of these species rather than a major shift in proportion. CONCLUSION: The data suggest that genotype positive subjects more frequently had higher levels of "red" and "orange" complex species that are known to be strongly associated with measures of periodontal inflammation.     

白细胞介素-1单核苷酸多态性与甘肃回族、东乡族人群慢性牙周炎的相关性研究

目的 通过检测并分析白细胞介素(IL)-1B+3954位点的单核苷酸多态性(SNP),探索其与甘肃回族与东乡族人群慢性牙周炎的关系.方法 收集215例回族、东乡族慢性牙周炎患者及219例正常对照组健康者的静脉血,提取外周静脉血白细胞DNA,采用聚合酶链式反应-限制性片段长度多态性技术(PCR-RFLP)方法检测IL-1...     

Therapy with adjunctive doxycycline local delivery in patients with type 1 diabetes mellitus and periodontitis

OBJECTIVES: The purpose of this study was to evaluate the effect of subgingival administration of doxycycline as an adjunct to periodontal therapy in type 1 diabetes mellitus (DM) patients. MATERIAL AND METHODS: Twenty-two paired periodontal defects > or =5.0 mm were treated in 11 patients (35-55 years old). After initial therapy the sites were randomly assigned into test (scaling and root planing+subgingival administration of 10% doxycycline hyclate gel) or control (scaling and root planing+subgingival placebo gel) groups. The clinical parameters of clinical attachment level (CAL), probing depth (PD) and gingival margin level (GML) for recession determination were assessed at baseline, after 6 weeks, and 6, 9 and 12 months, using a computerized probe. Data were statistically evaluated using Duncan and F tests. RESULTS: Between study group comparisons indicated PD reduction and CAL gain were greater in the test group than in the control group at 6 weeks and 6, 9 and 12 months but only statistically significant at 12 months (p<0.05). Within study group comparisons indicated statistically significant differences were found for CAL and PD values favouring the adjunctive doxycycline group from baseline to 6 weeks and 6, 9 and 12 months (p<0.05). CONCLUSIONS: These findings suggest that subgingivally delivered doxycycline hyclate produces additional favorable clinical results to periodontal therapy in type 1 DM patients.     

Interleukin-4 (C-590T) and interferon-gamma (G5644A) gene polymorphisms in patients with periodontitis

Background and Objective:  Periodontitis is a multifactorial disease and immunologic and genetic factors have an important role in its pathogenesis. Mutation in the promoter regions of the interleukin-4 and interferon-γ genes has been reported to modify the protein expression. The objective of this study was to evaluate the possible role of interleukin-4 (C-590T) and interferon-γ (G5644A) polymorphisms in the susceptibility to periodontitis.
Material and Methods:  In this case–control study, 53 patients (36 women and 17 men), comprising 27 patients with aggressive periodontitis and 26 patients with chronic periodontitis, and 56 healthy volunteers, were enrolled. DNA was isolated from all subjects, and the polymerase chain reaction-sequence specific primer method was used to study the interleukin-4 (C-590T) and interferon-γ (G5644A) gene polymorphisms.
Results:  Our results showed no significant difference in the allele and genotype frequencies of interleukin-4 (C-590T) and interferon-γ (G5644A) gene polymorphisms between patients with periodontal disease and controls.
Conclusion:  The results suggest that the interleukin-4 (C-590T) and interferon-γ (G5644A) gene polymorphisms may not be associated with the susceptibility of Iranian individuals to periodontitis.     

The IL1A (-889) gene polymorphism is associated with chronic periodontal disease in a sample of Brazilian individuals

BACKGROUND AND OBJECTIVE: It has been proposed that genotypes reflective of polymorphisms in cytokine genes can predispose individuals to disease by enhancing inflammatory processes. The C/T polymorphism at position -889 of the IL1A gene influences interleukin-1alpha expression, with the T allele inducing higher expression. The aim of this study was to evaluate the association of the IL1A (-889) gene polymorphism in Brazilian individuals with different clinical forms of periodontitis and severity of disease. MATERIAL AND METHODS: DNA was obtained from oral swabs of 163 Brazilian individuals and was amplified using the polymerase chain reaction (PCR). Products were submitted to digestion and were analyzed by electrophoresis to distinguish the C and T alleles. RESULTS: A significant difference in the genotype distribution was observed when comparing the chronic periodontitis group with the control group, evaluating only nonsmokers (chi-squared analysis = 9.91; p = 0.007), as well as when smokers were included (chi-squared analysis = 6.36; p = 0.04). Moreover, we observed a higher incidence of the T allele in the chronic periodontitis group (37.8%) when compared with the control group (18.4%) in nonsmokers (p = 0.006, odds ratio = 2.69, confidence interval = 1.27-5.68) and also when smokers were included (p = 0.03, odds ratio = 1.87, confidence interval = 0.98-3.56). No statistical difference was observed when the aggressive periodontitis group was compared with the control group. With regard to severity of disease, no statistical difference was observed. CONCLUSION: These data show an association of the IL1A (-889) polymorphism with chronic periodontitis in Brazilian individuals.     

牙周治疗对2型糖尿病患者血清白细胞介素6及糖化白蛋白的影响

目的 探讨牙周非手术治疗对伴牙周炎2型糖尿病患者血清白细胞介素-6及糖化白蛋白的影响.方法 选择2型糖尿病伴重度慢性牙周炎患者32例,于牙周治疗前、后一个月分别检测血清白细胞介素-6(IL-6)和糖化白蛋白(FA)、甘油三酯(TG)水平、牙周指数.结果 经牙周治疗后,伴重度牙周炎的2型糖尿病患者除TG水平外,血清IL-6阳性百分率(P＜0.05)、FA水平(P＜0.001)有明显下降;探诊深度(PD)、附着丧失(AL)治疗后均较基线明显下降(P＜0.001).结论 非手术牙周治疗可能降低糖尿病牙周炎患者外周血循环IL-6水平,糖化白蛋白水平、牙周状况也有明显改善.     

Interactions between stress,interleukin-1beta,interleukin-6 and cortisol in periodontally diseased patients

BACKGROUND/AIMS: The aim of the present study was to measure interleukin-1beta, interleukin-6 and cortisol levels in the peripheral blood of periodontally diseased patients in order to record any interactions with psychosocial stress. MATERIAL AND METHODS: The test group comprised 16 patients with untreated and 14 with treated aggressive generalized periodontitis (AGP), five patients with untreated aggressive localized periodontitis (ALP) and five with chronic generalized periodontitis (CGP). The control group comprised 40 periodontally healthy probands. Blood was taken from the cephalic vein of all patients and controls at the same time (8 a.m.) each day. IL-1beta, IL-6 and cortisol levels were then measured with a sensitive ELISA, the 'Quantikine HS Immunoassay Kit' (Biermann Diagnostica, Bad Nauheim, FRG). The clinical examination covered probing depth, gingival recession, gingival index, plaque index and clinical attachment level. A questionnaire was used to ask the patients and controls about their attitude to life and the stress induced by their jobs and their families. Previous and current levels of tobacco consumption were also recorded. Statistical evaluation was based on the Mann-Whitney U-Wilcoxon test for comparison of blood serum values and clinical parameters between patients and controls, and the Kruskal-Wallis test for intergroup comparison. All data were correlated by means of Spearman's rank correlation coefficient, and significance levels relating to stress and smoking were determined with the chi-square test. RESULTS: With respect to cortisol, the results showed no significant differences either between the patient groups or in comparison with the controls. IL-1beta was detected only in the AGP patients and their controls, but with no significant differences. IL-6 was detected in virtually all patients and controls, but with no significant differences. Only in the untreated AGP patients was IL-6 significantly elevated (P < 0.05) and a slight correlation with attachment loss recorded. In all AGP patients a slight correlation between IL-1beta and IL-6 was recorded. Evaluation of the questionnaire revealed a higher proportion of untreated AGP patients than of controls with a pessimistic attitude to life. In all AGP patients, family-induced stress and smoking were found to correlate with attachment loss. In the untreated AGP patients, smoking correlated with IL-1beta protein content, and in the controls there was a moderate correlation between smoking and IL-6 levels. CONCLUSIONS: The present study found no correlation between the immunological mediators (IL-1beta, IL-6), glucocorticoids (cortisol) and the registered stress values. However, the patients with untreated AGP showed signs of a pessimistic attitude to life, and an elevated IL-6 level was recorded in the peripheral blood. As a restrictive factor it should be borne in mind that the number of patients investigated was too small for adequate conclusions to be drawn.     

Association among interleukin-6 gene polymorphism, diabetes and periodontitis in a Chinese population

Objectives:  Diabetics significantly increase risk for periodontitis. Interleukin-6 (IL-6) gene polymorphism may play certain roles in the progression of periodontitis with diabetes. The purpose of this study was to assess the association among IL-6 gene polymorphisms, type 2 diabetes mellitus (T2DM) and chronic periodontitis (CP) in a Chinese population.
Material and methods:  DNA was obtained from 159 patients with CP, 88 patients with T2DM, 110 patients with CP&T2DM and 135 control subjects. The -174/-572/-597 polymorphisms of IL-6 gene were investigated by restriction fragment length polymorphism of polymerase chain reaction products. The results were further confirmed by sequencing. Significance was set at P  < 0.008 after Bonferroni correction.
Results:  Among four groups, CP&T2DM group showed the lowest IL-6-572 CC genotype and C-allele frequencies (54.5% and 74.1%). In this regard, there were significant differences between CP&T2DM group and the control group [ P  = 0.006, odds ratio (OR)  =  0.475, 95% CI: 0.279–0.808 and P  = 0.002, OR = 0.502, 95% CI: 0.319–0.788 respectively]. Logistic regression with adjustment for age, gender, body mass index, smoking and stress showed no significant difference in terms of IL-6-572 genotypes ( P  = 0.058, OR= 0.523, 95% CI: 0.268–1.022).
Conclusions:  The IL-6-572 genotype and allele distributions are unique to subjects with CP&T2DM in a Chinese population.     

Genetic polymorphisms in the MMP-1 and MMP-3 gene may contribute to chronic periodontitis in a Brazilian population

OBJECTIVES: Matrix metalloproteinase-1 and -3 (MMP-1, MMP-3) represent proteinases that degrade macromolecules of the extracellular matrix. These enzymes play a fundamental role during destruction of periodontal tissues. Genetic polymorphisms were characterized in the promoter region of the MMP-1 and MMP-3 genes. The aim of this study was to investigate the relationship between these genetic variations with chronic periodontitis in a Brazilian population. MATERIAL AND METHODS: Non-smoking subjects (n = 114) exhibiting sites > or = 5 mm clinical attachment loss were recruited for study. Control subjects (n = 109) should not exhibit clinical signals of periodontitis. MMP-1 (-1607 1G/2G, -519 A/G) and MMP-3 (-1612 5A/6A) gene promoter polymorphisms were genotyped using PCR-RFLP methods. RESULTS: Analysis of polymorphisms showed no differences in distribution of the -1607 1G/2G and -519 A/G variants in the MMP-1 gene between the healthy and periodontitis group (p > 0.05). However, the distribution of genotype frequencies of the -1612 5A/6A polymorphism in the MMP-3 gene showed that the 5A/5A genotype was significantly more frequent in the periodontitis group (p = 0.008). The same was not observed in the 5A/6A genotype once only one 5A allele is carried. We also observed a trend to increase the frequency of the MMP-1/MMP-3 haplotype (2G/5A) in the periodontitis group (p = 0.08). CONCLUSION: On the basis of the results, no significant association is found for the MMP-1 polymorphisms with susceptibility of periodontitis, while the MMP-3 gene polymorphism may contribute to periodontal tissue destruction during periodontitis in Brazilian subjects.     

牙周非手术治疗对伴二型糖尿病的慢性牙周炎大鼠血清白细胞介素6表达及颈动脉血管壁的影响

目的 探讨牙周非手术治疗对伴二型糖尿病（T2DM）慢性牙周炎（CP）大鼠模型中血清白细胞介素6（IL-6）的表达及颈动脉血管壁的影响。方法 将28只6周龄清洁级SD大鼠随机分为A组（正常对照组,7只）、B组（T2DM+CP组,21只）,将B组按照不同干预措施随机分成B1（自然进程组）、B2（机械治疗组）、B3（机械治疗+盐酸米诺环素+抗生素组）,用酶联免疫吸附测定法进行血清IL-6的测定,苏木精-伊红（HE）染色后光镜下观察颈动脉组织的病理变化。结果 A组血管壁形态正常;B1组内皮细胞脱落消失,中膜弹性纤维排列紊乱,平滑肌组织局部坏死呈无定型颗粒,少量钙盐沉积,管壁增厚明显;B2、B3组内皮细胞脱落消失,中膜部分平滑肌细胞空泡变性,血管壁无明显增厚。B1组血清IL-6含量随时间持续升高,高于A组（P<0.001）。各干预组血清IL-6的含量在第一次干预后1周达到峰值,随后逐渐下降,在第二次干预后5周,B2、B3组均显著低于B1组（P<0.001）。结论 对于伴有糖尿病的牙周炎大鼠,单纯牙周机械治疗在短期内可能会引起血清IL-6水平升高,远期疗效则可能会降低机体的炎症状态,且伴有颈动脉血管病变的改善;联合使用局部及全身抗生素可能优化其疗效。