Analysis of the association of polymorphism in the osteoprotegerin gene with susceptibility to chronic kidney disease and periodontitis

Analysis of angiotensin II type 1 receptor and osteoprotegerin gene polymorphism on the risk of cardiovascular mortality risk and progressivity of chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a significant global public health issue with increased risk of atherosclerotic cardiovascular disease (ASCVD) and cardiovascular mortality. Single nucleotide polymorphisms (SNPs) on angiotensin II type 1 receptor (AT1R) A1166C and osteoprotegerin (OPG) C950T gene have received significant attention as a genetic risk factor for cardiovascular disease and CKD.

METHODS

This was a cross-sectional study involving 75 adults with CKD recruited from Nephrology Outpatient Clinics of Universitas Airlangga Hospital, Surabaya, Indonesia. Demographic data was obtained from interviews and medical records. The "CKD Patch" application was used to asses ASCVD and cardiovascular mortality risk scores. Statistical analysis was performed by using SPSS version 26.

RESULTS

We detected four different AT1R gene polymorphisms (A1166C, A1160C, G1170T, and G1181C) and two OPG gene polymorphisms (T950C and G1181C) in Indonesian CKD patients. A1160C and G1181C polymorphisms were novel SNPs, newly discovered in this research. No significant association was found between AT1R SNPs and kidney prognostic markers or ASCVD risk/mortality risk scores. However, for OPG C950T we found that TT genotype had a significantly higher ACR than TC or CC genotype (P=0.032). As for OPG G1181C, we found that GG genotype had a higher serum creatinine and albumin to creatinine ratio compared to GC and CC genotypes (P=0.004 and 0.029, respectively). Genotype GC for OPG G1181C was also shown to be protective for having better kidney markers and lowest cardiovascular mortality risk compared to GG and CC genotypes (P=0.018 and 0.032, respectively).

CONCLUSIONS

Increased ASCVD risk and mortality risk score was not found on individuals with AT1R gene SNPs. However, for OPG gene polymorphism, C950T and G1181C were associated with kidney progression and cardiovascular mortality.

A Cross-Sectional Study of Serum Glutathione Peroxidase: An Antioxidative Marker in Chronic Periodontitis and Chronic Kidney Disease

Background and aim: Oxidative stress as an individual risk for periodontitis and chronic kidney disease (CKD) has been elaborated through various mechanical pathways, yet its role in association with both diseases remains unexplored. Thus, the current study aims in evaluating serum glutathione peroxidase, an oxidative stress marker in CKD patients with periodontitis, and compare it with the healthy controls.

Methodology: One hundred and twenty subjects were divided into four groups as control (C=30 subjects), periodontitis and non-CKD patients (CP=30 patients), non-periodontitis and CKD patients (CKD=30 patients), and periodontitis and CKD patients (CKD+CP=30 patients). Demographic variables, periodontal parameters, such as plaque index (PI), gingival index (GI), probing pocket depth (PPD), percentage proportion of sites with probing pocket depth more than 5 mm, clinical attachment loss (CAL), percentage proportion of sites with clinical attachment loss more than 3 mm and serum stress marker, and glutathione peroxidase were compared between the groups and the results were statistically analyzed.

Results: The demographic variables did not differ significantly between the groups, except for age. The means PI, GI, PPD, percentage proportion of sites with probing pocket depth more than 5 mm, CAL, percentage proportion of sites with clinical attachment loss were higher in CKD+CP. The glutathione peroxidase was significantly higher in CP group (p=0.001) and significantly correlated with periodontal parameters.

Conclusion: The oxidative stress marker glutathione peroxidase was higher in CP, followed by the CKD groups. This could pave a strong link of oxidative stress as a risk factor for chronic periodontitis, as well as chronic kidney disease.

Isolated Systolic Blood Pressure and Red-Complex Bacteria-A Risk for Generalized Periodontitis and Chronic Kidney Disease

Hypertension is a risk factor for generalized periodontitis (GP) and chronic kidney diseases (CKD). However, the role of isolated systolic blood pressure as one of the major risks for these inflammatory diseases has not been explored. Very limited studies exist identifying the red-complex bacteria in association with the isolated systolic blood pressure. Hence, the main objective of this study was to assess the isolated systolic blood pressure and the red-complex bacteria along with the demographic variables, periodontal parameters, and renal parameters in patients with generalized periodontitis and chronic kidney disease. One hundred twenty participants (age 30-70 years) were divided into four groups-Group C: control (systemically and periodontally healthy subjects), Group GP: generalized periodontitis, Group CKD: subjects with CKD with good periodontal health, Group CKD + GP: subjects with both generalized periodontitis and CKD. Demographic variables and periodontal parameters were measured and recorded. Blood pressure measurements and a detailed history and renal parameters such as serum creatinine, eGFR, and fasting blood sugar were recorded. The red-complex bacteria (RCB) were assessed in the subgingival plaque samples of all four groups using RT-PCR. Older participants (above 50 years) showed worse periodontal scores in the CKD + GP group along with elevated isolated systolic blood pressure, higher serum creatinine, and fasting blood sugar. eGFR was significantly decreased compared to the other groups. Bacterial counts were higher in the GP + CKD group, suggesting that they may be at a higher risk for generalized periodontitis and chronic kidney disease. Isolated systolic blood pressure (ISBP) and RCB were significantly correlated with the renal and periodontal parameters. A log-linear relationship exists between periodontal disease, CKD, RCB, and isolated systolic hypertension levels.

[A Meta-analysis of the effect of non-surgical periodontal therapy on inflammatory factors in patients with chronic kidney disease and periodontitis]

OBJECTIVE

A study was conducted to systematically evaluate the clinical efficacy of inflammatory factors in patients with chronic kidney disease and periodontitis after non-surgical periodontal therapy.

METHODS

We searched the databases of CNKI, Wanfang, CBM, PubMed, Embase, and Cochrane Library from inception to December 2019. Two reviewers independently collected all literature related to inflammatory factors in patients with chronic kidney disease and periodontitis after non-surgical periodontal therapy. These factors include C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). The literature was screened according to the inclusion and exclusion criteria. The quality of the studies was strictly evaluated, and the data were extracted. The literature of randomized controlled trials in accordance with the standards was Meta-analyzed with Revman 5.3 software.

RESULTS

Six randomized controlled trials were included. Compared with the control groups, the results of meta-analysis showed that non-surgical periodontal therapy significantly reduced the levels of CRP [MD=-0.58, 95%CI (-1.13, -0.02), P=0.04] and IL-6 [MD=-2.76, 95%CI (-5.15, -0.37), P=0.02] in these patients but not that of TNF-α [MD=-3.87, 95%CI (-8.79, 1.05), P=0.12].

CONCLUSIONS

Simultaneous regular renal treatment and non-surgical periodontal therapy can help relieve the periodontal damage on patients with chronic kidney disease and periodontitis. Moreover, it can improve the status of some inflammatory factors. This finding is conducive to the control and treatment of chronic kidney disease and periodontitis and needs to be a focus of research and in clinical operation.

Polymorphisms of Il-10 (-1082) and RANKL (-438) Genes and the Failure of Dental Implants

Background. Genetic polymorphisms in certain cytokines and chemokines have been investigated to understand why some individuals display implant flaws despite having few risk factors at the time of implant. Purpose. To investigate the association of genetic polymorphisms in interleukin- (IL-) 10 [-1082 region (A/G)] and RANKL [-438 region (A/G)] with the failure of dental implants. Materials and Methods. This study included 90 partially edentulous male and female patients who were rehabilitated with a total of 245 Straumann dental implants. An implant was considered a failure if any of the following occurred: mobility, persistent subjective complaint, recurrent peri-implant infection with suppuration, continuous radiolucency around the implant, probing depth ≥ 5 mm, and bleeding on probing. Buccal mucosal cells were collected for analysis of RANKL438 and IL-10. Results. The implant success rate in this population was 34.4%. The mutant allele (G) in RANKL had an incidence of 52.3% and mutant allele (A) in IL-10 was observed in 37.8%. No statistically significant difference was detected between the failure of the implant and the genotypes and allelic frequencies. Conclusion. No association was detected between the genetic polymorphisms of RANKL (-438) and IL-10 (-1082) and the failure of dental implants in the population studied.

Gene polymorphisms in chronic periodontitis

We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP) susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in the IL1, IL6, IL10, vitamin D receptor, and CD14 genes may be associated with CP in certain populations. However, carriage rates of the rare (R)-allele of any polymorphism varied considerably among studies and most of the studies appeared under-powered and did not correct for other risk factors. Larger cohorts, well-defined phenotypes, control for other risk factors, and analysis of multiple genes and polymorphisms within the same pathway are needed to get a more comprehensive insight into the contribution of gene polymorphisms in CP.