Periodontal disease, oxidative stress, and risk for preeclampsia

Periodontitis and Preeclampsia in Pregnancy: A Systematic Review and Meta-Analysis

OBJECTIVES

A conflicting body of evidence suggests localized periodontal inflammation spreads systemically during pregnancy inducing adverse pregnancy outcomes. This systematic review and meta-analysis aim to specifically evaluate the relationship between periodontitis and preeclampsia.

METHODS

Electronic searches were carried out in Medline, Pubmed, Embase, Lilacs, Cochrane Controlled Clinical Trial Register, CINAHL, ClinicalTrials.gov, and Google Scholar with no restrictions on the year of publication. We identified and selected observational case-control and cohort studies that analyzed the association between periodontal disease and preeclampsia. This meta-analysis was conducted following the PRISMA checklist and MOOSE checklist. Pooled odds ratios, mean difference, and 95% confidence intervals were calculated using the random effect model. Heterogeneity was tested with Cochran's Q statistic.

RESULTS

Thirty studies including six cohort- and twenty-four case-control studies were selected. Periodontitis was significantly associated with increased risk for preeclampsia (OR 3.18, 95% CI 2.26 - 4.48, p < 0.00001), especially in a subgroup analysis including cohort studies (OR 4.19, 95% CI 2.23 - 7.87, p < 0.00001). The association was even stronger in a subgroup analysis with lower-middle-income countries (OR 6.70, 95% CI 2.61 - 17.19, p < 0.0001).

CONCLUSIONS

Periodontitis appears as a significant risk factor for preeclampsia, which might be even more pronounced in lower-middle-income countries. Future studies to investigate if maternal amelioration of periodontitis prevents preeclampsia might be warranted.

Periodontal Inflamed Surface Area Is Associated With Increased Gestational Blood Pressure and Uric Acid Levels Among Pregnant Women From Rural North China

Background

Periodontal disease has been associated with gestational complications and both conditions have a high prevalence in rural populations from developing regions. A cross-sectional study was carried out to explore the relationship between periodontal inflamed surface area (PISA), blood pressure (BP), and, serum uric acid levels (UA) in a group of rural North Chinese pregnant women in the third trimester of pregnancy.

Methods

Three hundred and thirty-five rural women aged 20–34 years, with normal body mass index (BMI) were examined in a cross-sectional study during their third trimester of gestation. Exclusion criteria were history of pregnancy complications, multiple pregnancy, smoking habits, diabetes, hypertension or any known infectious disease. Socio-demographic variables, including age and socioeconomic status (SES), systolic blood pressure (SBP) and diastolic blood pressure (DBP) readings, serum UA levels, and PISA values were recorded. A structural equation model was implemented with two constructed latent variables including “Dem” (comprising of age and SES category to represent unobserved demographic variables) and, “BP” (comprising of SBP and DBP to account for measurement error and lack of multiple BP readings). The model accounted for co-variance of BP and UA, and implemented simultaneous regressions for BP and UA as outcomes, upon Dem and PISA values as exogenous variables.

Results

The median PISA score was 1,081.7 (IQR = 835.01), reflecting high levels of periodontal inflammation in the sample. SEM showed a significant association of PISA with BP (estimate = 0.011, 95% CI = 0.009–0.012 p < 0.001) and UA (estimate = 0.001, 95% CI = 0.001–0.001, p < 0.001).

Conclusion

Higher PISA values were significantly associated with higher blood pressure and uric acid levels among rural pregnant women in a cross-sectional sample from a center in North China after accounting for a latent demographic construct derived from age and SES.

Role of maternal nutrition and oxidative stress in placental telomere attrition in women with preeclampsia

Background:Maternal nutrition influences the growth and development of the fetus and influences pregnancy outcome. We have earlier demonstrated altered maternal nutrition and increased oxidative stress in women with preeclampsia. Oxidative stress is known to be associated with reduced telomere length and short telomere aggregates. Increased telomere attrition leads to increased cellular senescence and tissue ageing. Methods:The present review focuses on the role of maternal nutrition and oxidative stress in telomere attrition in preeclampsia. Results and Conclusion:Future studies need to examine the association between maternal nutritional status in early pregnancy, oxidative stress and telomere attrition in preeclampsia.

Periodontal disease and adverse pregnancy outcomes

Periodontal diseases are considered not only to affect tooth-supporting tissues but also to have a cause-and-effect relationship with various systemic diseases and conditions, such as adverse pregnancy outcomes. Mechanistic studies provide strong evidence that periodontal pathogens can translocate from infected periodontium to the feto-placental unit and initiate a metastatic infection. However, the extent and mechanisms by which metastatic inflammation and injury contribute to adverse pregnancy outcomes still remain unclear. The presence of oral bacteria in the placenta of women with term gestation further complicates our understanding of the biology behind the role of periodontal pathogens in pregnancy outcomes. Epidemiological studies demonstrate many methodological inconsistencies and flaws that render comparisons difficult and conclusions insecure. Therefore, despite the fact that a number of prospective studies show a positive association between periodontal diseases and various adverse pregnancy outcomes, the evidence behind it is still weak. Future well-designed explanatory studies are necessary to verify this relationship and, if present, determine its magnitude. The majority of high-quality randomized controlled trials reveal that nonsurgical periodontal therapy during the second trimester of gestation does not improve pregnancy outcomes. From a biological standpoint, this can be partially explained by the fact that therapy rendered at the fourth to sixth months of pregnancy is too late to prevent placental colonization by periodontal pathogens and consequently incapable of affecting pathogen-induced injury at the feto-placental unit. Thus, interventions during the preconception period may be more meaningful. With the increase in our understanding on the potential association between periodontal disease and adverse pregnancy outcomes, it is clear that dental practitioners should provide periodontal treatment to pregnant women that is safe for both the mother and the unborn child. Although there is not enough evidence that the anti-infective therapy alters pregnancy outcomes, it improves health-promoting behavior and periodontal condition, which in turn advance general health and risk factor control.

Poor Oral Health as a Determinant of Malnutrition and Sarcopenia

Aging is accompanied by profound changes in many physiological functions, leading to a decreased ability to cope with stressors. Many changes are subtle, but can negatively affect nutrient intake, leading to overt malnutrition. Poor oral health may affect food selection and nutrient intake, leading to malnutrition and, consequently, to frailty and sarcopenia. On the other hand, it has been highlighted that sarcopenia is a whole-body process also affecting muscles dedicated to chewing and swallowing. Hence, muscle decline of these muscle groups may also have a negative impact on nutrient intake, increasing the risk for malnutrition. The interplay between oral diseases and malnutrition with frailty and sarcopenia may be explained through biological and environmental factors that are linked to the common burden of inflammation and oxidative stress. The presence of oral problems, alone or in combination with sarcopenia, may thus represent the biological substratum of the disabling cascade experienced by many frail individuals. A multimodal and multidisciplinary approach, including personalized dietary counselling and oral health care, may thus be helpful to better manage the complexity of older people. Furthermore, preventive strategies applied throughout the lifetime could help to preserve both oral and muscle function later in life. Here, we provide an overview on the relevance of poor oral health as a determinant of malnutrition and sarcopenia.

siRNA-mediated NCAM1 gene silencing suppresses oxidative stress in pre-eclampsia by inhibiting the p38MAPK signaling pathway

Pre-eclampsia (PE), whose pathophysiology and etiology remain undefined, represents a leading consequence of fetal and maternal mortality and morbidity. Oxidative stress (OS) is recognized to involve in this disorder. In this study, we hypothesized that neural cell adhesion molecule 1 (NCAM1) gene silencing would suppress the OS in the pregnancy complicated by PE. Initially, clinical samples were collected for determination of NCAM1 expression in placental tissues and levels of OS products in blood. To assess the regulatory mechanism of NCAM1 knockdown on OS, we used small interfering RNA (siRNA) to silence NCAM1 expression in human umbilical vein endothelial cells (HUVECs). Next, cells were treated with or without hypoxia/reoxygenation to observe the level changes of OS products and p38 mitogen-activated protein kinase (p38MAPK) pathway-related genes. Finally, an evaluation of HUVEC migration and invasion abilities was conducted by wound-healing and transwell assays. Placenta of pregnancy with PE presented significantly increased NCAM1 expression in comparison to placenta of normal pregnancy. Meanwhile, enhanced OS in blood of pregnant women with PE was observed relative to women with normal pregnancy. siRNA-mediated knockdown of NCAM1 gene could inhibit the p38MAPK signaling pathway, repress OS, and promote cell migration and invasion in HUVECs, indicating that NCAM1 inhibition could reduce the influence of PE. Importantly, blocking the p38MAPK signaling pathway reversed the inhibitory role of NCAM1 gene silencing on PE. Collectively, this study defines potential role of NCAM1 gene silencing as a therapeutic target in PE through inhibiting OS and enhancing HUVEC migration and invasion by disrupting the p38MAPK signaling pathway.

Translating prenatal oral health clinical standards into dental education: results and policy implications

OBJECTIVES

To evaluate characteristics of pregnant women served through the University of North Carolina's (UNC) prenatal oral health program (pOHP) dental clinic and community healthcare pathways to inform efforts in promoting prenatal oral health policies.

METHODS

The pOHP provides medical and dental students and practitioners with interprofessional experiences caring for pregnant women. A retrospective chart audit captured 314 pregnant women who made appointments over 33 months. Descriptive statistics and bivariate comparisons were computed to assess factors associated with dental appointment attendance and treatment completion.

RESULTS

There were 564 pregnant women, with mean age of 29 years and gestation of 25 weeks, referred to the pOHP dental clinic from UNC OB-GYN and 20 community sites. Only 56% (N = 314) scheduled an appointment. Of the 314 appointed women, 55% (N = 172) attended at least one appointment. The majority (87%) presented with acute and/or complex treatment needs. Medicaid status was positively associated with appointment attendance (P = 0.001). Less than half (42%) of the women completed treatment prior to delivery. Mean maternal age, gestational age, and weeks to estimated date of delivery (EDD) were not significantly associated with completed treatment.

CONCLUSIONS

This study provides descriptive evidence of an academic, interprofessional program's ability to provide safety-net dental care to pregnant women in the state of North Carolina. Results underscore the need for dental services among pregnant women, signaling for promotion of prenatal oral health clinical standards and informing policy on the state and national levels to maximize dental coverage.

Periodontal diseases and adverse pregnancy outcomes: Is there a role for vitamin D?

Studies have shown a relationship between maternal periodontal diseases (PDs) and premature delivery. PDs are commonly encountered oral diseases which cause progressive damage to the periodontal ligament and alveolar bones, leading to loss of teeth and oral disabilities. PDs also adversely affect general health by worsening of cardiovascular and metabolic diseases. Moreover, maternal PDs are thought to be related to increasing the frequency of preterm-birth with low birth weight (PBLBW) in new-borns. Prematurity and immaturity are the leading causes of prenatal and infant mortality and is a major public health problem around the world. Inflamed periodontal tissues generate significantly high levels of proinflammatory cytokines that may have systemic effects on the host mother and the fetus. In addition, the bacteria that cause PDs produce endotoxins which can harm the fetus. Furthermore, studies have shown that microorganisms causing PDs can get access to the bloodstream, invading uterine tissues, to induce PBLBW. Another likely mechanism that connects PDs with adverse pregnancy outcome is maternal vitamin D status. A role of inadequate vitamin D status in the genesis of PDs has been reported. Administration of vitamin D supplementation during pregnancy could reduce the risk of maternal infections and adverse pregnancy outcomes. As maternal PDs are significant risk factors for adverse pregnancy outcome, preventive antenatal care for pregnant women in collaboration with the obstetric and dental professions are required.

LPS from P. gingivalis Negatively Alters Gingival Cell Mitochondrial Bioenergetics

OBJECTIVE

Oral inflammatory pathologies are linked to increased oxidative stress, thereby partly explaining their relevance in the etiology of systemic disorders. The purpose of this work was to determine the degree to which LPS from Porphyromonas gingivalis, the primary pathogen related to oral inflammation, altered gingival mitochondrial function and reactive oxygen species generation.

METHODS

Human gingival fibroblast (HGF-1) cells were treated with lipopolysaccharide of P. gingivalis. Mitochondrial function was determined via high-resolution respirometry.

P GINGIVALIS

Mitochondrial function was determined via high-resolution respirometry.

RESULTS

LPS-treated HGF-1 cells had significantly higher mitochondrial complex IV and higher rates of mitochondrial respiration. However, this failed to translate into greater ATP production, as ATP production was paradoxically diminished with LPS treatment. Nevertheless, production of the reactive H2O2 was elevated with LPS treatment.

CONCLUSIONS

LPS elicits an increase in gingival cell mitochondria content, with a subsequent increase in reactive oxygen species production (i.e., H2O2), despite a paradoxical reduction in ATP generation. These findings provide an insight into the nature of oxidative stress in oral inflammatory pathologies.

Epidemiology of association between maternal periodontal disease and adverse pregnancy outcomes--systematic review

BACKGROUND AND OBJECTIVES

There is still debate regarding potential relationships between maternal periodontitis during pregnancy and adverse pregnancy outcomes. The aim of this systematic review was to synthesize the available epidemiological evidence on this association.

DATA SOURCES

Combined electronic and hand search of MEDLINE, EMBASE, WEB OF SCIENCE and Cochrane Central Register databases.

STUDY ELIGIBILITY CRITERIA

Original publications reporting data from cross-sectional, case-control or prospective cohort epidemiological studies on the association between periodontal status and preterm birth, low birthweight (LBW) or preeclampsia. The search was not limited to publications in English. All selected studies provided data based on professional assessments of periodontal status, and outcome variables, including preterm birth (<37 weeks gestation), LBW (<2500 g), gestational age, small for gestational age, birthweight, pregnancy loss or miscarriage, or pre-eclampsia.

PARTICIPANTS

Pregnant women with or without periodontal disease, and with or without adverse pregnancy outcomes, assessed either during pregnancy or postpartum. No intervention studies were included. Study appraisal and synthesis methods - Publications were assessed based on predefined screening criteria including type of periodontal assessment, consistency in the timing of the periodontal assessment with respect to gestational age, examiner masking and consideration of additional exposures and confounders.

RESULTS

Maternal periodontitis is modestly but significantly associated with LBW and preterm birth, but the use of a categorical or a continuous exposure definition of periodontitis appears to impact the findings: Although significant associations emerge from case-control and cross-sectional studies using periodontitis "case definitions," these were substantially attenuated in studies assessing periodontitis as a continuous variable. Data from prospective studies followed a similar pattern, but associations were generally weaker. Maternal periodontitis was significantly associated with pre-eclampsia.

LIMITATIONS

There is a high degree of variability in study populations, recruitment and assessment, as well as differences in how data are recorded and handled. As a result, studies included in meta-analyses show a high degree of heterogeneity.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Maternal periodontitis is modestly but independently associated with adverse pregnancy outcomes, but the findings are impacted by periodontitis case definitions. It is suggested that future studies employ both continuous and categorical assessments of periodontal status. Further use of the composite outcome preterm LBW is not encouraged.

Relationship between gingival inflammation and pregnancy

An increase in the prevalence and severity of gingival inflammation during pregnancy has been reported since the 1960s. Though the etiology is not fully known, it is believed that increasing plasma sex steroid hormone levels during pregnancy have a dramatic effect on the periodontium. Current works of research have shown that estrogen and progesterone increasing during pregnancy are supposed to be responsible for gingivitis progression. This review is focused not only on epidemiological studies, but also on the effects of progesterone and estrogen on the change of subgingival microbiota and immunologic physiological mediators in periodontal tissue (gingiva and periodontal ligament), which provides current information about the effects of pregnancy on gingival inflammation.

Relationship between periodontitis and pre-eclampsia: a meta-analysis

BACKGROUND

Studies have suggested controversial results regarding a possible association between pre-eclampsia (PE) and periodontal disease (PD) and no meta-analysis has been performed to clarify this issue.

METHODS

A literature search of electronic databases was performed for articles published through March 24, 2013, followed by a manual search of several dental and medical journals. The meta-analysis was conducted according to the recommendations of the Cochrane Collaboration and PRISMA. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Heterogeneity was assessed with the χ(2)-based Cochran Q test and I(2) statistic. The level of significance was set at P <0.05.

RESULTS

Fifteen studies were included, including three cohort and 12 case-control studies. A positive association was found between PE and PD (OR 2.17, 95% CI 1.38-3.41, P = 0.0008). However, a high and significant heterogeneity was found (χ(2) = 62.42, P<0.00001, I(2) = 75%). In most cases, subgroup analysis had low power to detect significant differences between PE and non-PE groups.

CONCLUSION

Based on the findings of the meta-analysis, PD appears to be a possible risk factor for PE. However, given the important differences in the definitions and diagnoses of PD and PE among the studies, as well as their lack of good methodological quality, future trials are needed to confirm the results of the present meta-analysis.

Antibodies anti-CagA cross-react with trophoblast cells: a risk factor for pre-eclampsia?

BACKGROUND

Previous studies reported an epidemiological association between CagA-positive H. pylori strains and pre-eclampsia. As antibodies anti-CagA cross-react with endothelial cells and trophoblast cells show an endothelial phenotypic profile, we hypothesized that anti-CagA antibodies may recognize antigens of cytotrophoblast cells, thus impairing their function.

MATERIALS AND METHODS

Placenta samples were obtained from healthy women. Cytotrophoblast cells were cultured in a medium containing increasing concentration of polyclonal anti-CagA antibodies. Binding of anti-CagA antibodies to cytotrophoblast cells was evaluated by cell ELISA and immunofluorescence assay. Invasive potential of those cells was assessed by an invasion culture system and by measuring of MMP-2. Protein sequencing was performed on antigens precipitated by anti-CagA antibodies. Measurement of phosphorylated ERK expression and NF-kB DNA-binding activity in trophoblast cells incubated with anti-CagA or irrelevant antibodies was also performed.

RESULTS

Anti-CagA antibodies recognized β-actin of cytotrophoblast cells, showing a dose-dependent binding. Incubation of cytotrophoblast cells with increasing doses of anti-CagA antibodies significantly reduced their invasiveness and determined a significant decrease in phosphorylated ERK expression and a reduced NF-kB translocation activity.

CONCLUSIONS

This study shows that anti-CagA antibodies recognize β-actin of cytotrophoblast cells, reducing their invasiveness ability, possibly giving a biological explanation for the epidemiological association.

Periodontitis as a risk factor for preeclampsia

BACKGROUND

Periodontitis is an inflammatory process caused by a specific group of microorganisms, resulting in the destruction of the tooth-supporting tissue and the resorption of the alveolar bone. Therefore, periodontitis has been considered a risk factor for preeclampsia because infection is one of the factors involved in the etiology and pathogenesis of preeclampsia. The aim of the present study is to determine whether periodontitis is a risk factor for preeclampsia and to identify other possible risk factors.

METHODS

A case-control study was performed with 574 puerperae under care at the university hospital at the Universidade Federal de Pernambuco in the city of Recife, Brazil. Data collection was preceded by a training exercise and a pilot study. Biologic and socioeconomic data were collected along with medical and dental records. A periodontal examination was performed on all dental elements to determine probing depth and gingival recession. The association between periodontitis and preeclampsia was first adjusted for the variables within each block, and adjusted for the variables of all blocks in the final multivariate model.

RESULTS

The multivariate logistic regression analysis showed that, after adjustment for other risk factors, periodontitis remained an independent risk factor for preeclampsia (adjusted odds ratio [OR] = 8.60, confidence interval [CI] = 3.92 to 18.88, P < 0.001 and adjusted OR = 2.03, 95% CI = 1.43 to 2.90, P < 0.001, when using the Centers for Disease Control and Prevention/American Academy of Periodontology definition).

CONCLUSION

The results suggest that within the population studied, periodontitis was a risk factor for preeclampsia.

Effect of non-surgical periodontal therapy on C-reactive protein, oxidative stress, and matrix metalloproteinase (MMP)-9 and MMP-2 levels in patients with type 2 diabetes: a randomized controlled study

BACKGROUND

It is well accepted that glycemic control in patients with diabetes mellitus (DM) is affected by systemic inflammation and oxidative stress. The effect of periodontal therapy on these systemic factors may be related to improvement on glycemic status. The aim of the present study is to assess over a period of 6 months the effect of non-surgical periodontal therapy on serum levels of high-sensitivity C-reactive protein (hsCRP), d-8-iso prostaglandin F2a (d-8-iso) as a marker of oxidative stress, and matrix metalloproteinase (MMP)-2 and MMP-9 on patients with type 2 DM.

METHODS

Sixty participants with type 2 DM and moderate to severe periodontal disease were randomized into intervention (IG) and control (CG) groups. IG received scaling and root planing, whereas CG received supragingival cleaning at baseline and scaling and root planing at 6 months. Participants of both groups were evaluated at baseline and 1, 3, and 6 months. Periodontal data recorded at each visit included probing depth, clinical attachment loss, bleeding on probing, and gingival index. Blood was collected at each visit for the assay of serum glycated hemoglobin A1c (A1c), hsCRP, d-8-iso, MMP-2, and MMP-9.

RESULTS

Although there was a trend to a reduction in hsCRP, d-8-iso and MMP-9 it did not reach statistical significance. MMP-2 levels remained unchanged after periodontal treatment.

CONCLUSION

Effective non-surgical periodontal treatment of participants with type 2 DM and moderate to severe periodontal disease improved significantly A1c levels but did not result in a statistically significant improvement in hsCRP, d-8-iso, MMP-2, and MMP-9 levels.