Expression of the Interleukin-10 Signaling Pathway Genes in Individuals With Down Syndrome and Periodontitis

Periodontal disease in down syndrome: Predisposing factors and potential non-surgical therapeutic approaches

BACKGROUND

Periodontal diseases (PDs) have been documented to be significantly more prevalent and severe in patients with Down syndrome (DS). Different immunological and microbiological factors contributed to predisposing these patients to progressive and recurrent PDs.

AIM

The aim of this review was to investigate the altered immunological responses and oral microbiota disorders as well as focus on adjunctive non-surgical methods for the treatment of PDs and its applicability in patients with DS.

MATERIAL AND METHODS

A literature review was conducted addressing the following topics: (1) the altered immunological responses, (2) orofacial disorders related to DS patients, (3) oral microbiota changing, and (4) adjunctive non-surgical treatment and its efficacy in patients with DS.

RESULTS

Due to the early onset of PDs in children with DS, the need for prompt and effective treatment in these patients is essential.

DISCUSSION AND CONCLUSION

So, investigating underlying factors may open a new window to better understand the pathology of PDs in DS people and thus, find better strategies for treatment in such group. Although non-surgical treatments such as photodynamic therapy and probiotic consumption represented acceptable outcomes in different examined patients without DS, data about the application of these convenience and no need for local anesthesia methods in patients with DS is limited.

Identifying metabolic parameters related to severity and extent of periodontitis in down syndrome patients

BACKGROUND AND OBJECTIVE

Systemic metabolic status and periodontitis can be related in patients with Down syndrome (DS). The objective of this study was to identify metabolic indicators (anthropometric measurements, blood pressure, and serum markers) related to severity and extent of periodontitis in DS patients.

METHODS

A cross-sectional study was conducted with 49 patients with DS. Periodontal evaluation included the periodontal probing depth (PPD), clinical attachment level (CAL), gingival bleeding index (GBI), and visible plaque index (VPI). Periodontitis severity was classified by the stages system. The extent of periodontitis was assessed as the percentage of sites with CAL ≥3 mm, CAL ≥4 mm, PPD ≥4 mm, and PPD ≥5 mm. The metabolic condition of the participants was determined by analyzing anthropometric parameters, blood pressure, and serum markers. Data were analyzed using the Mann-Whitney test, Spearman's correlation coefficient, and multivariate regression analysis.

RESULTS

Periodontitis stage 3/4 was detected in 32.7% of patients, with high values of VPI (54.6 ± 35.8) and GBI (42.4 ± 33.3). The severity of periodontitis was related to higher mean corpuscular hemoglobin (β = .291, p = .028) and mean corpuscular volume values (β = .293, p = .046). Arm circumference measurements were inversely related to CAL ≥3 mm (β = -.408, p = .023), PPD ≥4 mm (β = -.475, p = .006), and PPD ≥5 mm (β = -.443, p = .010).

CONCLUSIONS

The findings suggest that the severity and extent of periodontitis may be related to some metabolic parameters in DS patients.

Identification of Neuropeptides as Potential Crosstalks Linking Down Syndrome and Periodontitis Revealed by Transcriptomic Analyses

Background

This bioinformatics study was aimed to investigate the relationship between periodontitis (PD) and Down Syndrome (DS) regarding potential crosstalk genes, related neuropeptides, and biological processes.

Methods

Data for PD (GSE23586, GSE10334 and GSE16134) and DS (GSE35665) were downloaded from NCBI Gene Expression Omnibus (GEO). Following normalization and merging of PD data, differential expression analysis was performed (p value < 0.05 and ∣log FC | ≥0.5). The common deregulated genes between PD and DS were considered as crosstalk genes. The significantly differentially expressed genes were used to construct the coexpression network and to further identify coexpression gene modules. To acquire the significant modules, the significant expression level of genes in the module was used to analyze the enrichment of genes in each module. Neuropeptides were assessed from NeuroPedia database. Neuropeptide genes and crosstalk genes were merged and mapped into PPI network, and the correlation coefficient (Spearman) was determined for the crosstalk genes.

Results

138 crosstalk genes were predicted. According to the functional enrichment analysis, these genes significantly regulated different biological processes and pathways. In enrichment analysis, the significant module of DS was pink module, and turquoise module was significant in PD. Four common crosstalk genes were acquired, i.e., CD19, FCRL5, FCRLA, and HLA-DOB. In the complex network, INS and IGF2 interacted with CASP3 and TP53, which commonly regulated the MAPK signaling pathway. Moreover, the results showed that TP53 interacted with IGF2 and INS inducing the dysregulation of PI3K-Akt signaling pathway. UBL was positively correlated with crosstalk genes in both diseases. LEP was revealed to be both a neuropeptide and crosstalk gene and was positively correlated with other crosstalk genes.

Conclusion

Different crosstalk genes, related neuropeptides, and biological pathways and processes were revealed between PD and DS, which can serve as a theoretical basis for future research.

Alzheimer's Disease in the Down Syndrome: An Overview of Genetics and Molecular Aspects

The overexpression of the amyloid precursor protein (APP) gene, encoded on chromosome 21, has been associated in Down syndrome (DS) with the development of early-onset Alzheimer's disease (EOAD). The increase in APP levels leads to an overproduction of amyloid-β (Aβ) peptide that accumulates in the brain. In response to this deposition, microglial cells are active and generate cascade events that include release cytokines and chemokine. The prolonged activation microglial cells induce neuronal loss, production of reactive oxygen species, neuron death, neuroinflammation, and consequently the development of Alzheimer's disease (AD). The intrinsically deficient immune systems in people with DS result in abnormalities in cytokine levels, which possibly contribute to the development of neurodegenerative disorders such as AD. Knowledge about the biomarkers involved in the process of neurodegeneration and neuroinflamation is important for understanding the mechanisms involved in the incidence and the precocity of AD in individuals with DS.

Susceptibility to Heart Defects in Down Syndrome Is Associated with Single Nucleotide Polymorphisms in HAS 21 Interferon Receptor Cluster and VEGFA Genes

BACKGROUND

Congenital heart defects (CHDs) are present in about 40-60% of newborns with Down syndrome (DS). Patients with DS can also develop acquired cardiac disorders. Mouse models suggest that a critical 3.7 Mb region located on human chromosome 21 (HSA21) could explain the association with CHDs. This region includes a cluster of genes (IFNAR1, IFNAR2, IFNGR2, IL10RB) encoding for interferon receptors (IFN-Rs). Other genes located on different chromosomes, such as the vascular endothelial growth factor A (VEGFA), have been shown to be involved in cardiac defects. So, we investigated the association between single nucleotide polymorphisms (SNPs) in IFNAR2, IFNGR2, IL10RB and VEGFA genes, and the presence of CHDs or acquired cardiac defects in patients with DS.

METHODS

Individuals (n = 102) with DS, and age- and gender-matched controls (n = 96), were genotyped for four SNPs (rs2229207, rs2834213, rs2834167 and rs3025039) using KASPar assays.

RESULTS

We found that the IFNGR2 rs2834213 G homozygous genotype and IL10RB rs2834167G-positive genotypes were more common in patients with DSand significantly associated with heart disorders, while VEGFA rs3025039T-positive genotypes (T/*) were less prevalent in patients with CHDs.

CONCLUSIONS

We identified some candidate risk SNPs for CHDs and acquired heart defects in DS. Our data suggest that a complex architecture of risk alleles with interplay effects may contribute to the high variability of DS phenotypes.

Apigenin as a Candidate Prenatal Treatment for Trisomy 21: Effects in Human Amniocytes and the Ts1Cje Mouse Model

Human fetuses with trisomy 21 (T21) have atypical brain development that is apparent sonographically in the second trimester. We hypothesize that by analyzing and integrating dysregulated gene expression and pathways common to humans with Down syndrome (DS) and mouse models we can discover novel targets for prenatal therapy. Here, we tested the safety and efficacy of apigenin, identified with this approach, in both human amniocytes from fetuses with T21 and in the Ts1Cje mouse model. In vitro, T21 cells cultured with apigenin had significantly reduced oxidative stress and improved antioxidant defense response. In vivo, apigenin treatment mixed with chow was administered prenatally to the dams and fed to the pups over their lifetimes. There was no significant increase in birth defects or pup deaths resulting from prenatal apigenin treatment. Apigenin significantly improved several developmental milestones and spatial olfactory memory in Ts1Cje neonates. In addition, we noted sex-specific effects on exploratory behavior and long-term hippocampal memory in adult mice, and males showed significantly more improvement than females. We demonstrated that the therapeutic effects of apigenin are pleiotropic, resulting in decreased oxidative stress, activation of pro-proliferative and pro-neurogenic genes (KI67, Nestin, Sox2, and PAX6), reduction of the pro-inflammatory cytokines INFG, IL1A, and IL12P70 through the inhibition of NFκB signaling, increase of the anti-inflammatory cytokines IL10 and IL12P40, and increased expression of the angiogenic and neurotrophic factors VEGFA and IL7. These studies provide proof of principle that apigenin has multiple therapeutic targets in preclinical models of DS.

Inhibitory designer receptors aggravate memory loss in a mouse model of down syndrome

The pontine nucleus locus coeruleus (LC) is the primary source of noradrenergic (NE) projections to the brain and is important for working memory, attention, and cognitive flexibility. Individuals with Down syndrome (DS) develop Alzheimer's disease (AD) with high penetrance and often exhibit working memory deficits coupled with degeneration of LC-NE neurons early in the progression of AD pathology. Designer receptors exclusively activated by designer drugs (DREADDs) are chemogenetic tools that allow targeted manipulation of discrete neuronal populations in the brain without the confounds of off-target effects. We utilized male Ts65Dn mice (a mouse model for DS), and male normosomic (NS) controls to examine the effects of inhibitory DREADDs delivered via an AAV vector under translational control of the synthetic PRSx8, dopamine β hydroxylase (DβH) promoter. This chemogenetic tool allowed LC inhibition upon administration of the inert DREADD ligand, clozapine-N-oxide (CNO). DREADD-mediated LC inhibition impaired performance in a novel object recognition task and reversal learning in a spatial task. DREADD-mediated LC inhibition gave rise to an elevation of α-adrenoreceptors both in NS and in Ts65Dn mice. Further, microglial markers showed that the inhibitory DREADD stimulation led to increased microglial activation in the hippocampus in Ts65Dn but not in NS mice. These findings strongly suggest that LC signaling is important for intact memory and learning in Ts65Dn mice and disruption of these neurons leads to increased inflammation and dysregulation of adrenergic receptors.

Differential Expression of Inflammation-Related Genes in Down Syndrome Patients with or without Periodontal Disease

Aim

Aware that Down Syndrome patients present among their clinical characteristics impaired immunity, the aim of this study is to identify the statistically significant differences in inflammation-related gene expression by comparing Down Syndrome patients with Periodontal Disease (DS+PD+) with Down Syndrome patients without Periodontal Disease (DS+PD-), and their relationship with periodontitis as a chronic oral inflammatory clinical feature.

Materials and Methods

Case study and controls on eleven Down Syndrome patients (DS+PD+ vs. DS+PD-). RNA was extracted from peripheral blood using a Qiagen PAXgene Blood miRNA Kit when performing an oral examination. A search for candidate genes (92 selected) was undertaken on the total genes obtained using a Scientific GeneChip® Scanner 3000 (Thermo Fisher Scientific) and Clariom S solutions for human, mouse, and rat chips, with more than 20,000 genes annotated for measuring expression levels.

Results

Of the 92 inflammation-related genes taken initially, four genes showed a differential expression across both groups with a p value of <0.05 from the data obtained using RNA processing of the patient sample. Said genes were TNFSF13B (p = 0.0448), ITGB2 (p = 0.0033), ANXA3 (p = 0.0479), and ANXA5 (p = 0.016).

Conclusions

There are differences in inflammation-related gene expression in Down Syndrome patients when comparing patients who present a state of chronic oral inflammation with patients with negative rates of periodontal disease.

Periodontal disease in Down's syndrome patients. A retrospective study

AIM

The purpose of this study was to assess the periodontal condition of people with Down syndrome (DS). Furthermore, risk factors were identified for the development of periodontitis.

METHODS AND RESULTS

Data were collected at the Centre for Special Care Dentistry (CBT) Rijnmond from the records of all 183 registered patients with DS who were 18 years of age on 31 December 2013. Patients were divided into two groups on the basis of their periodontal status: healthy or periodontally compromised. A total of 36.6% of the DS patients had actually incurred damage by periodontitis. The risk factors were: high age at the time of intake, large number of treatment sessions, and impossibility for the "Dutch Periodontal Screening Index" to be measured. In conclusion, the early introduction and continuous attendance of DS patients in a CBT can contributed to better results for a healthy periodontal condition.

Interleukin-10 polymorphisms affect the key periodontal pathogens in Chinese periodontitis patients

Interleukin-10 (IL-10) polymorphisms have been shown to affect IL-10 production. This study investigated the influences of IL-10 polymorphisms on the susceptibility to chronic periodontitis (CP) and aggressive periodontitis (AP), and their possible role in the quantity of subgingival bacteria Aggregatibacter Actinomycetemcomitans and Porphyromonas gingivalis. 92 CP patients, 83 AP patients and 91 periodontal healthy controls were recruited. Serum IL-10 concentration was analyzed by enzyme-linked immunosorbent assay (ELISA). Gene polymorphisms were determined by multiplex SNaPshot technique. Bacteria were quantified by real-time polymerase chain reaction with TaqMan MGB probes. Taking into account age, gender and periodontal status, IL-10-592 AA, -819 TT and ATA/ATA genotype occurred more frequently in patients with CP than in healthy controls. In CP cases, higher quantity of subgingival A. actinomycetemcomitans and lower serum IL-10 levels could be detected in homozygous ATA/ATA carriers. These findings indicate that variants in IL-10 promoter gene were not only associated with predisposition to chronic periodontitis but also affected the subgingival number of A. Actinomycetemcomitans in a Chinese Han population.

Periodontal disease in patients with Down syndrome: A systematic review

BACKGROUND

The authors systematically reviewed the scientific evidence of an association between periodontal disease and Down syndrome (DS).

TYPES OF STUDIES REVIEWED

In this systematic review, the authors included observational studies in which the investigators assessed the prevalence, incidence, or experience of periodontal disease in patients with DS compared with that in healthy patients. The authors used the Population, Exposure, Comparison, Outcome structure. The population was patients of any age, the exposure was the presence of DS, the comparison was the absence of DS, and the outcome was the presence of periodontal disease. The authors conducted an electronic search in 5 databases through March 2017. Two independent reviewers assessed the risk of bias by using the Fowkes and Fulton scale. The authors performed a meta-analysis to compare periodontal disease among patients with DS and those without DS. The authors calculated a summary effect measure-standard mean difference-when evaluating the means of the oral hygiene index. The authors assessed the strength of evidence from the selected studies by using a modified Grading of Recommendations Assessment, Development and Evaluation system.

RESULTS

The authors included 23 case-control studies in the systematic review and submitted 3 to meta-analysis. In the qualitative analysis, results from most studies showed that the prevalence of some periodontal parameters was higher among patients with DS than among those without DS. Evaluations of the Fowkes and Fulton scale point to many methodological problems in the studies evaluated. Results of the meta-analysis revealed no differences between groups with regard to the oral hygiene index (standard mean difference, 0.05; 95% confidence interval, -0.55 to 0.65; I² = 0.0%).

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Further research is required, in particular well-designed studies that avoid the deficiencies identified in the studies in this review.

Porphyromonas gingivalis and its lipopolysaccharide differently modulate epidermal growth factor-dependent signaling in human gingival epithelial cells

Periodontitis is an inflammatory disease induced by pathogenic bacteria such as Porphyromonas gingivalis. Little is known about epidermal growth factor (EGF) signals in human gingival epithelial cells (HGEC), which are major targets of P. gingivalis, and how the expression of proteins participating in EGF signaling—that is, EGF-receptor (EGFR), suppressor of cytokine signaling-3 (SOCS-3), interferon regulatory factor-1 (IRF-1), and signal transducers and activators of transcription (STAT-3)—are modified. This study aimed to assess the effects of P. gingivalis and its purified lipopolysaccharide (LPS-Pg) on EGF signaling. HGEC were infected for 2 h in a dose-dependent manner with P. gingivalis and with heat-killed P. gingivalis, and activated for 2 and 24 h by 1 µg/mL of purified LPS-Pg. Quantitative reverse transcription polymerase chain reaction and Western blotting were performed to measure mRNA and protein levels for SOCS-3, IRF-1 EGF, EGFR, and STAT-3. The tyrosine-phosphorylation status of STAT-3 was also examined. The results showed that infection of HGEC cells with P. gingivalis, but not with heat-killed P. gingivalis, led to significant reductions in expression levels of mRNAs and proteins for SOCS-3, IRF-1, and EGFR, while LPS-Pg over time significantly increased the expression of these mRNAs and proteins. Tyrosine-phosphorylation of STAT-3 was significantly increased during infection with P. gingivalis and activation by LPS-Pg but not modified during infection with heat-killed P. gingivalis. This study highlights that P. gingivalis and its purified LPS differentially modulated the expression of proteins (SOCS-3, IRF-1, EGFR, and STAT-3) interfering with EGF signaling.

Outcomes of Dental Implant Therapy in Patients With Down Syndrome: A Systematic Review

OBJECTIVES

Patients with Down syndrome (DS) require an earlier and more frequent tooth replacement than rest of the population. The objective of this systematic review is to critically analyze and summarize studies to ascertain the outcomes and survival of dental implants placed in jaws of DS patients.

METHODS

Using the key words "dental implants," "Down syndrome," and "prosthodontics," an electronic search was conducted via PubMed/MEDLINE, ISI Web of Science, Google Scholar, Embase, and Central Register of Controlled Trials (CENTRAL) databases by 2 authors, S.N. and Z.K., independently. Retrieved studies were screened against the predefined exclusion and inclusion criteria. To estimate the risk of bias, quality assessment of included studies was carried using the 'Case Reports (CARE) guidelines'.

RESULTS

Primary search resulted in 156 studies. Eight studies met the inclusion criteria and reporting a total of 81 dental implants placed in 36 DS patients. The type of implant loading ranged from immediate to a delay of 1 year after placement of the implant. Implant diameter ranged from 3.3 to 4.5 mm, and height ranged from 8.5 to 18 mm. The follow-up ranged from 1 to 6 years. Of 81 implants placed, 21 implants (26%) were reported as failed.

CONCLUSIONS

Patients with DS have a higher risk of implant failure. However, the reason for the failure is not very well understood. Although case reports and case series suggest that implant survival is diminished in DS patients, large-scale randomized controlled trials are required to determine the exact mechanism associated with risks of implant failure.

What people with Down Syndrome can teach us about cardiopulmonary disease

Down syndrome is the most common chromosomal abnormality among live-born infants. Through full or partial trisomy of chromosome 21, Down syndrome is associated with cognitive impairment, congenital malformations (particularly cardiovascular) and dysmorphic features. Immune disturbances in Down syndrome account for an enormous disease burden ranging from quality-of-life issues (autoimmune alopecia) to more serious health issues (autoimmune thyroiditis) and life-threatening issues (leukaemia, respiratory tract infections and pulmonary hypertension). Cardiovascular and pulmonary diseases account for ∼75% of the mortality seen in persons with Down syndrome. This review summarises the cardiovascular, respiratory and immune challenges faced by individuals with Down syndrome, and the genetic underpinnings of their pathobiology. We strongly advocate increased comparative studies of cardiopulmonary disease in persons with and without Down syndrome, as we believe these will lead to new strategies to prevent and treat diseases affecting millions of people worldwide.

Dyslipidemia rather than Type 2 Diabetes Mellitus or Chronic Periodontitis Affects the Systemic Expression of Pro- and Anti-Inflammatory Genes

A high percentage of type 2 diabetes mellitus (T2D) patients are also affected by dyslipidemia and chronic periodontitis (CP), but no studies have determined the gene expression in patients that are simultaneously affected by all three diseases. We investigated the systemic expression of immune-related genes in T2D, dyslipidemia, and CP patients. One hundred and fifty patients were separated into five groups containing 30 individuals each: (G1) poorly controlled T2D with dyslipidemia and CP; (G2) well-controlled T2D with dyslipidemia and CP; (G3) normoglycemic individuals with dyslipidemia and CP; (G4) healthy individuals with CP; (G5) systemic and periodontally healthy individuals. Blood analyses of lipid and glycemic profiles were carried out. The expression of genes, including IL10, JAK1, STAT3, SOCS3, IP10, ICAM1, IFNA, IFNG, STAT1, and IRF1, was investigated by RT-qPCR. Patients with dyslipidemia demonstrated statistically higher expression of the IL10 and IFNA genes, while IFNG, IP10, IRF1, JAK1, and STAT3 were lower in comparison with nondyslipidemic patients. Anti-inflammatory genes, such as IL10, positively correlated with parameters of glucose, lipid, and periodontal profiles, while proinflammatory genes, such as IFNG, were negatively correlated with these parameters. We conclude that dyslipidemia appears to be the primary disease that is associated with gene expression of immune-related genes, while parameters of T2D and CP were correlated with the expression of these important immune genes.

Prevention and Periodontal Treatment in Down Syndrome Patients: A Systematic Review

The aim of this systematic literature review was to evaluate which type of periodontal preventive and therapeutic approaches presents superior outcomes in patients with Down syndrome (DS). Studies reporting different methods of periodontal care from DS patients were considered eligible. Included clinical studies should indicate at least two periodontal parameters in different periods of assessment. Screening of the articles, data extraction and quality assessment were conducted independently and in duplicate. Electronic search according to the PICO search, with both Key-words and MESH terms were conducted in MEDLINE, EMBASE and CENTRAL databases until March 2016. Manual search was conducted in four journals, namely Journal of Periodontology, Journal of Clinical Periodontology, Journal of Periodontal Research and Special Care in Dentistry and their electronic databases were searched. Electronic and manual search resulted in 763 papers, and of them 744 were excluded after title/abstract assessment. The full text of 19 potentially eligible publications was screened and 9 studies met inclusion criteria. The results demonstrated the importance to introduce youngest DS patients in preventive programs, as well as participation of parents, caregivers or institutional attendants in supervising/performing oral hygiene. In studies with higher frequency of attendance, all age groups presented superior preventive and therapeutic results, irrespective of the therapeutic approach used (surgical/nonsurgical/periodontal care program). The important factors for reducing periodontal parameters were the frequency of the appointments and association with chlorhexidine/plaque disclosing agents as adjuvant treatment. This systematic review demonstrated that early introduction in periodontal care, participation of parents/caregivers/institutional attendants, frequency of attendance and association with chemical adjuvants (independently of the periodontal treatment adopted) seems to improve periodontal outcomes in preventive and periodontal treatment of DS patients. Registration number (Prospero): CRD42016038433.

Effect on plaque control in children patients with Down syndrome using Digital Brush with or without chlorhexidine: a randomized clinical trial

OBJECTIVES

The aim of this study was to evaluate efficacy in children affected by Down syndrome of "Digital Brush" in terms of Plaque Index reduction added to the daily oral hygiene procedures.

METHODS

A total of 56 patients with Down syndrome were recruited and randomly assigned in two groups: both control and test groups underwent standard hygiene procedures of tooth brushing twice a day followed by the intervention of Digital Brush, TNT gauze impregnated with chlorhexidine 0.12%, for the test group and by sterile gauze soaked in water for the control group. Initial plaque index was measured for all patients (T0), subsequently were instructed to use either Digital Brush or gauze soaked with water for 2 weeks. At last, patients were reevaluated (T1) and the plaque index measured.

RESULTS

Plaque index improvement from T0 to T1 in control group was 11.7%, while in test group was 24.1%. The mean differences between test and control group was statistically significant (p < 0.001).

CONCLUSIONS

This study demonstrates how the Digital Brush, added to the daily oral hygiene procedures, obtains significant improvements in supragingival plaque control in children with Down syndrome.