Iron overload and periodontal status in patients with sickle cell anaemia: A case series

Impact of oral health conditions on the quality of life of children and adolescents with sickle cell anemia: A cross-sectional study

BACKGROUND

Sickle cell anemia (SCA) is the most common hemoglobinopathy in Brazil and worldwide and is part of a group of chronic genetic diseases resulting from abnormalities in the structure of hemoglobin.

AIM

To evaluate the impact of oral health conditions on the quality of life (QoL) of children and adolescents with SCA.

DESIGN

This is a cross-sectional study with a sample of 76 children and adolescents aged 8-14 years. For inclusion, they were required to have a diagnosis of HbSS SCA in their medical records, without a pain crisis or any dental emergency in the last three months. The children and adolescents with SCA were from Hematology and Hemotherapy Center of Maranhão. Demographic characteristics, socioeconomic status, oral hygiene, caries, malocclusion, and oral health-related quality of life (OHRQoL) were assessed. OHRQoL was assessed using the Child Perceptions Questionnaire. Descriptive statistics, Student's t and Mann-Whitney tests were performed (α = 5%).

RESULTS

Brown race was the most prevalent for both age groups (8-10 years-63.2% and 11-14 years-57.9%). Predominant monthly family income for both age groups was below $106. Visible plaque and gingival bleeding were higher in children aged 8-10 years. Dental caries significantly impacted the QoL of adolescents through the domain "oral symptom" (p = .031). Malocclusion significantly impacted the QoL of adolescents ("total score," p = .026; "social well-being", p = .045).

CONCLUSION

Oral health impairment negatively affected the QoL of adolescents with SCA.

Iron Status and Risk of Periodontitis and Dental Caries: A Mendelian Randomization Study

BACKGROUND

Previous studies have indicated a potential relationship between iron status and oral health outcomes, specifically periodontitis and dental caries. This study employed Mendelian randomization (MR) to investigate the causal effects of iron status on these oral health conditions. The focus of this study was on key iron biomarkers, namely serum iron, ferritin, transferrin saturation (TSAT), and total iron-binding capacity (TIBC).

METHODS

This two-sample MR analysis employed genome-wide association study (GWAS) data. The instrumental variables (IVs) were selected based on their genome-wide significance and independence from confounders. The statistical analyses employed the inverse variance weighted (IVW) method, MR-Egger regression, weighted median, and weighted mode. Additionally, sensitivity analyses were conducted to verify the reliability of the causal association results.

RESULTS

The MR analysis indicated a suggestive negative causal relationship between TIBC and periodontitis, with an odds ratios of 0.875 and a 95% CI of 0.766-0.998, with a P-value of .047. No significant other associations were found. The results of sensitivity analyses demonstrated the robustness of these findings.

CONCLUSION

This MR study suggested a potential negative association between TIBC and periodontitis, highlighting the importance of considering iron status in the clinical management of chronic periodontitis. However, more standardized, multi-population studies are needed to confirm this causality.

Ferroptosis: A New Challenge and Target in Oral Diseases

OBJECTIVE

Ferroptosis, an iron-dependent intracellular programmed cell death mechanism discovered in the last decade, has emerged as a novel and intriguing concept in oral diseases, distinct from apoptosis, necrosis, and pyroptosis. This process plays a critical role in the pathophysiology of inflammation, trauma, and tumors, with evidence of its presence in multiple organ systems, including the liver, kidneys, and heart. In recent years, many studies have found that ferroptosis is closely related to oral diseases, and a number of pathogenic pathways and therapeutic strategies have been reported. However, ferroptosis remains an underexplored area in oral diseases, with multiple secrets waiting to be uncovered.

METHOD

We collected articles related to ferroptosis and oral diseases and analyzed the mechanisms and therapeutic strategies associated with ferroptosis in different oral diseases.

RESULTS

In this review, we present a comprehensive analysis of ferroptosis and oral diseases, emphasizing its core mechanisms and associated therapeutic approaches. Furthermore, we give an outlook for future explorations of ferroptosis related to oral diseases.

CONCLUSION

This review provides dental researchers and clinicians with a current state of ferroptosis in oral diseases, thereby inspiring noval investigations and discoveries.

Ferroptosis and cuproptosis in periodontitis: recent biological insights and therapeutic advances

Periodontitis is a significant global public health issue associated with the onset and progression of various systemic diseases, thereby requiring additional research and clinical attention. Although ferroptosis and cuproptosis have emerged as significant areas of research in the medical field, their precise roles in the pathogenesis of periodontitis remain unclear. We aim to systematically summarize the current research on ferroptosis and cuproptosis in periodontal disease and investigate the roles of glutathione pathway and autophagy pathway in connecting ferroptosis and cuproptosis during periodontitis. Further, we propose that a homeostatic imbalance of copper and iron, driven by periodontal pathogens, may contribute to elevated periodontal oxidative stress, representing a potential unifying link between ferroptosis and cuproptosis involved in periodontitis. This article presents a comprehensive overview of the molecular mechanisms underlying ferroptosis and cuproptosis in periodontitis, offering novel theoretical insights into its pathogenesis and potential therapeutic targets.

Effects of the ferroptosis inducer erastin on osteogenic differentiation and biological pathways of primary osteoblasts

BACKGROUND

Periodontitis is a chronic destructive inflammatory disease exacerbated by osteoblast dysfunction. Ferroptosis has emerged as a significant factor that could contribute to the pathological changes observed in periodontitis. However, the impact of ferroptosis on osteogenic differentiation and gene expression patterns of primary osteoblasts remain elusive.

METHODS

In this study, osteoblasts were osteogenically induced for specific durations with and without the ferroptosis inducer erastin. Subsequently, cell proliferation, ferroptosis-related molecules, and osteogenic differentiation capacity were assessed. Furthermore, the differences in transcriptome expression following erastin treatment were analyzed by RNA sequencing.

RESULTS

The results demonstrated that erastin treatment induced ferroptosis, resulting in suppressed cell proliferation and impaired osteogenic differentiation. Transcriptomic analysis revealed significant alterations in processes such as hydrogen peroxide catabolism, response to lipid peroxidation, and metal iron binding, as well as BMP receptor activity and collagen type XI trimer.

CONCLUSION

The ferroptosis inducer erastin inhibited osteoblast proliferation and differentiation. Our study provides novel insights into the effect of ferroptosis on osteogenesis, suggesting that targeting ferroptosis may present a promising approach in the treatment of periodontitis.

Role of ferroptosis in Porphyromonas gingivalis-induced impairment of epithelial junction

Objectives

This study aims to clarify the effect of ferroptosis by P. gingivalis on periodontal epithelium impairment and potential mechanisms.

Materials and methods

The expression of epithelial junction proteins (CDH1, OCLN, ZO-1), FTL and GPX4 in healthy and periodontitis tissues was analyzed using bioinformatics analysis and validated in vivo. An in vitro model was constructed to evaluate ferroptosis by mitochondria morphology, content of iron and GSH, and level of lipid peroxidation, FTL, GPX4 and SLC7A11. The iron concentration was changed with iron chelator DFO and iron supplementation FAC. The epithelial impairment was assessed by protein expression. To investigate the mechanism, si-MYB (a negative transcription factor of SLC7A11) and GPX4 inhibitor RSL3 were employed.

Results

CDH1, OCLN, ZO-1 and GPX4 expression was decreased, while FTL expression was elevated in periodontitis tissues. Infected cells showed ferroptosis change of the mitochondria with higher level of lipid peroxidation, iron, FTL and lower level of GPX4, GSH, SLC7A11. FAC augmented ferroptosis and weakened epithelial junction, while DFO exhibited a counteractive effect. Silencing MYB rescued SLC7A11, GPX4 and epithelial junction proteins, which was hindered by RSL3.

Conclusions

Our study demonstrated that P. gingivalis weakened the oral epithelial barrier by causing ferroptosis via inhibiting SLC7A11/GSH/GPX4 axis.

Interleukin-17 alleviates erastin-induced alveolar bone loss by suppressing ferroptosis via interaction between NRF2 and p-STAT3

AIM

To investigate the relationship between interleukin-17 (IL-17), ferroptosis and osteogenic differentiation.

MATERIALS AND METHODS

We first analysed the changes in ferroptosis-related molecules in experimental periodontitis models. The effects of erastin, a small-molecule ferroptosis inducer, and IL-17 on alveolar bone loss and repair in animal models were then investigated. Primary mouse mandibular osteoblasts were exposed to erastin and IL-17 in vitro. Ferroptosis- and osteogenesis-related genes and proteins were detected. Further, siRNA, immunofluorescence co-localization and immunoprecipitation were used to confirm the roles of the nuclear factor erythroid-2-related factor 2 (NRF2) and phosphorylated signal transducer and activator of transcription 3 (p-STAT3), as well as their interaction.

RESULTS

The levels of NRF2, glutathione peroxidase 4 and solute carrier family 7 member 11 were lower in the ligated tissues than in normal periodontal tissues. Alveolar bone loss in an in vivo experimental periodontitis model was aggravated by erastin and alleviated by IL-17. In vitro, IL-17 ameliorated erastin-inhibited osteogenic differentiation by reversing ferroptosis. Altered NRF2 expression correlated with changes in ferroptosis-related molecules and osteogenesis. Furthermore, the physical interaction between NRF2 and p-STAT3 was confirmed in the nucleus. In IL-17 + erastin-stimulated osteoblasts, the p-STAT3-NRF2 complex might actively participate in the downstream transcription of ferroptosis- and osteogenesis-related genes.

CONCLUSIONS

IL-17 administration conferred resistance to erastin-induced osteoblast ferroptosis and osteogenesis. The possible mechanism may involve p-STAT3 directly interacting with NRF2.

Ferroptosis of macrophages facilitates bone loss in apical periodontitis via NRF2/FSP1/ROS pathway

Apical periodontitis (AP) is an infectious disease that causes periapical tissue inflammation and bone destruction. Ferroptosis, a novel type of regulated cell death, is closely associated with inflammatory diseases and the regulation of bone homeostasis. However, the exact involvement of ferroptosis in the bone loss of AP is not fully understood. In this study, human periapical tissues were collected, and a mouse model was established to investigate the role of ferroptosis in AP. Colocalization staining revealed that ferroptosis in macrophages contributes to the inflammatory bone loss associated with AP. A cell model was constructed using RAW 264.7 cells stimulated with LPS to further explore the mechanism underlying ferroptosis in macrophages upon inflammatory conditions, which exhibited ferroptotic characteristics. Moreover, downregulation of NRF2 was observed in ferroptotic macrophages, while overexpression of NRF2 upregulated the level of FSP1, leading to a reduction in reactive oxygen species (ROS) in macrophages. Additionally, ferroptotic macrophages released TNF-α, which activated the p38 MAPK signaling pathway and further increased ROS accumulation in macrophages. In vitro co-culture experiments demonstrated that the osteogenic ability of mouse bone marrow stromal cells (BMSCs) was suppressed with the stimulation of TNF-α from ferroptotic macrophages. These findings suggest that the TNF-α autocrine-paracrine loop in ferroptotic macrophages can inhibit osteogenesis in BMSCs through the NRF2/FSP1/ROS signaling pathway, leading to bone loss in AP. This study highlights the potential therapeutic value of targeting ferroptosis in the treatment of inflammatory bone diseases.

Prevalence of orofacial alterations in patients with sickle-cell disease: Systematic review and meta-analysis

OBJECTIVE

The aim of this study was to identify the prevalence of orofacial alterations in sickle-cell disease (SCD) and to compare it with the general population.

STUDY DESIGN

This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. The search was conducted on PubMed, Embase, Scientific Electronic Library Online, Web of Science, Cochrane Library, gray literature, and references of the included articles.

RESULTS

A total of 770 records were found, and 28 studies were selected. In SCD, the prevalence of decreased bone density was 57% (95% CI: 35%-80%), with Q: P < .01 and I² = 95%; for stepladder pattern was 30% (IC: 13%-47%), Q: P < .01 and I²: 93%; for delayed eruption was 20% (95% CI: 6%-34%), with Q: P < .01 and I² = 86, Q: P < .01 and I² = 99%; and for malocclusion, 66% (95% CI: 39%-92%), Q: P < .01 and I² = 98%. A high risk of bias was observed in relation to the sample size of the studies. A limited number of articles compared the prevalence of orofacial alterations in patients with SCD and healthy individuals.

CONCLUSIONS

Decreased bone density, malocclusion, orofacial pain, tooth necrosis, eruption delay, periodontal disease, and neuropathies may be present in patients with SCD with variable prevalence.

Ferroptosis: A New Development Trend in Periodontitis

Periodontitis is a chronic inflammatory disease associated with bacterial biofilm. It is characterized by loss of periodontal support tissue and has long been considered as a "silent disease". Because it is difficult to prevent and has a health impact that can not be ignored, researchers have been focusing on a mechanism-based treatment model. Ferroptosis is an iron-dependent regulatory form of cell death, that directly or indirectly affects glutathione peroxidase through different signaling pathways, resulting in a decrease in cell antioxidant capacity, accumulation of reactive oxygen species and lipid peroxidation, which cause oxidative cell death and tissue damage. Recently, some studies have proven that iron overload, oxidative stress, and lipid peroxidation exist in the process of periodontitis. Based on this, this article reviews the relationship between periodontitis and ferroptosis, in order to provide a theoretical reference for future research on the prevention and treatment of periodontal disease.

Association between periodontal inflamed surface area and serum acute phase biomarkers in patients with sickle cell anemia

OBJECTIVES

The aim of the present cross-sectional study was to investigate the association between periodontal inflamed surface area (PISA) and serum inflammatory biomarkers in patients with sickle cell anemia.

DESIGN

Patients with sickle cell anemia (n = 80) and systemically healthy individuals (n = 80) were enrolled in the study. Crisis episodes were recorded and blood samples were collected from patients with sickle cell anemia. Clinical periodontal parameters and PISA values were calculated from all patients. Ferritin and high sensitivity C-reactive protein (hs-CRP) levels were analyzed biochemically.

RESULTS

In sickle cell anemia group, presence of periodontitis (p < 0.001) was more frequent than periodontal health (p < 0.001). All clinical periodontal recordings and PISA values were higher in the sickle cell anemia group compared to controls (p < 0.001). Patients with PISA > 776 mm² had 6.06-fold greater chances of having hs-CRP levels above 10 mg/L (OR = 6.06; 95 % CI: 1.9-19.26) and had 31.41-fold greater chances of having ferritin levels above 1000 ng/L (OR = 31.41; 95 % CI: 6.62-149.16). Also, they had 3.27-fold greater risk of having crisis frequency above three times per year (OR = 3.27; 95 % CI: 1.05-10.23) after adjusting for confounders.

CONCLUSION

In patients with sickle cell anemia, positive association was evident between PISA values and serum acute phase biomarkers levels as well as the frequency of acute painful crisis. Patients with increased inflammatory burden may have a higher likelihood of developing periodontitis in the presence of sickle cell anemia. PISA value could be a candidate disease activity indicator in patients with an underlying hematological condition.

Role of NOD2 and hepcidin in inflammatory periapical periodontitis

The immunological response occurring during periapical inflammation includes expression of nucleotide binding oligomerization domain containing 2 and hepcidin. Nucleotide binding oligomerization domain containing 2 deficiency increases infiltration of inflammatory cells close to alveolar bone. Hepcidin has an important role in iron metabolism affecting bone metabolism.We investigated the role of nucleotide binding oligomerization domain containing 2 and hepcidin in inflammatory periapical periodontitis. Periapical periodontitis was induced in rats and confirmed by micro-computed tomography. Nucleotide binding oligomerization domain 2 and hepcidin were evaluated through immunohistochemistry. Bioinformatics analysis was undertaken usingthe Kyoto Encyclopedia of Genes and Genomes and Gene Ontology databases. Micro-computer tomography revealed alveolar bone resorption in the periapical region and furcation area of mandibular molars in rats of the periapical periodontitis group. Immunohistochemistry showed increased expressionof nucleotide binding oligomerization domain containing 2 and hepcidin around root apices in rats of the periapical periodontitis group. Bioinformatics analysis of differentially expressed genes in inflamed and non-inflamed tissues revealed enrichment in the NOD-like receptor signaling pathway. Our data suggest that nucleotide binding oligomization domain contain2 and hepcidin have important roles in periapical periodontitis severity because they can reduce alveolar bone loss.They could elicit new perspectives for development of novel strategies for periapical periodontitis treatment.

High serum iron markers are associated with periodontitis in post-menopausal women: A population-based study (NHANES III)

AIM

To investigate the association between increased serum markers of iron (ferritin and transferrin saturation) and the severity and extent of periodontitis in post-menopausal (PM) women.

MATERIALS AND METHODS

Data from 982 PM women participating in NHANES III were analysed. Exposures were high ferritin (≥300 μg/ml) and transferrin saturation (≥45%). The primary outcome was moderate/severe periodontitis defined according to Centers for Disease Control and Prevention and the American Academy of Periodontology. The extent of periodontitis was also assessed as outcome: proportion of sites affected by clinical attachment loss ≥4 mm and probing depth ≥4 mm. Crude and adjusted prevalence ratio (PR) and mean ratio (MR) were estimated using Poisson regression.

RESULTS

The prevalence of moderate/severe periodontitis was 27.56%. High ferritin was associated with moderate/severe periodontitis in the crude (PR 1.55, p = .018) and in the final adjusted model (PR 1.53, p = .008). High ferritin and transferrin saturation levels were associated with a higher proportion of sites with clinical attachment loss ≥4 mm (p < .05).

CONCLUSIONS

The increasing serum iron markers seem to contribute to periodontitis severity and extent in PM women.

Investigation of the relationship between periodontal and systemic inflammation in children with Sickle Cell Disease: A case- control study

Periodontal diseases are chronic inflammatory diseases and tissue destruction increases with oxidative stress in periodontal tissues. Periodontal diseases are associated with systemic diseases such as diabetes, cardio-vascular diseases and rheumatoid arthritis by means of systemic inflammation. Sickle cell disease (SCD) is a chronic inflammatory disease in which vaso-occlusive crisis and endothelial dysfunction are present. It is not known whether the chronic systemic inflammation seen in SCD affect periodontal tissues. The aim of this study was to investigate the relationship between periodontal and systemic inflammation in children with SCD. Forty-three children with SCD and 43 healthy children were included in the study. Physical, dental and periodontal statuses were examined, blood and saliva samples were taken. Levels of pro-inflammatory and oxidative stress mediators in serum and saliva were evaluated. The periodontal findings of the groups were similar. The majority of the subjects in both groups had gingival inflammation. In SCD group, significantly higher serum high sensitive C-reactive protein (Hs-CRP), interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, total oxidant status (TOS), nitric oxide (NO) and salivary IL-6 were observed (p < 0.05). There were positive correlations between salivary IL-6 levels and serum Hs-CRP levels (r = 0.303, p < 0.05). In addition; it was determined that salivary IL-6, TNF-α and NO levels were increased 3-6 times in children with a history of painful crisis or acute chest syndrome compared to children who had never had a painful crisis or acute chest syndrome. Although, observed oral health status was similar in both groups, salivary cytokine levels were increased in children with SCD. The higher salivary cytokine levels may be associated with chronic systemic inflammation and vaso-occlusion observed in children with SCD.

The relationship between periodontal status and rheumatoid arthritis - systematic review

There have been numerous publications investigating the relationship between periodontitis (PD) and rheumatoid arthritis (RA) so far.

This publication presents the common risk factors for the development of PD and RA. The major impact of the pathological bacterial factor and cigarette smoking with chronic inflammation playing the key role in both diseases has been confirmed by numerous studies in various populations over the years. More research focuses nowadays also on the role of improper diet and obesity. Pathophysiological pathways, such as increased concentration of proinflammatory cytokines, indirectly affecting the cardiovascular complications and coagulation disorders, which has an impact on function disorders of tissue metalloproteinase inhibitors and the plasminogen activation system, were also researched.

This systematic review of current literature has shown numerous discrepancies in previous analyses and the need for further detailed research on the relationship between periodontal status and RA.