Revisiting Alpha-Synuclein Pathways to Inflammation.

Alpha-synuclein (α-Syn) is a short presynaptic protein with an active role on synaptic vesicle traffic and the neurotransmitter release and reuptake cycle. The α-Syn pathology intertwines with the formation of Lewy Bodies (multiprotein intraneuronal aggregations), which, combined with inflammatory events, define various α-synucleinopathies, such as Parkinson's Disease (PD). In this review, we summarize the current knowledge on α-Syn mechanistic pathways to inflammation, as well as the eventual role of microbial dysbiosis on α-Syn. Furthermore, we explore the possible influence of inflammatory mitigation on α-Syn. In conclusion, and given the rising burden of neurodegenerative disorders, it is pressing to clarify the pathophysiological processes underlying α-synucleinopathies, in order to consider the mitigation of existing low-grade chronic inflammatory states as a potential pathway toward the management and prevention of such conditions, with the aim of starting to search for concrete clinical recommendations in this particular population.

Parkinson's Disease, Periodontitis and Patient-Related Outcomes: A Cross-Sectional Study.

Background and objectives: People with Parkinson's disease (PD) may be at risk of having bad periodontal status. A consistent periodontal examination is critical to investigate how it impacts on PD quality of life. We aimed to assess the periodontal status of people with PD, and its association with quality of life and self-perceived xerostomia. Materials and Methods: To this end, from February to March 2020, we consecutively enrolled 28 PD individuals, and motor and non-motor symptoms of PD were assessed using the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS). We performed full-mouth periodontal examination and gathered information on self-perceived quality of life in PD, oral health impact profile (OHIP-14) and xerostomia. Results: The prevalence of periodontitis was 75.0% and most cases were identified as severe (46.4%). Upper extremity rigidity, hand posture and kinetic tremors were significantly correlated with worse periodontal status. PDQ-8 showed to be correlated with self-perceived oral health-related quality of life and xerostomia levels. Conclusions: This group of people with PD had a high prevalence of periodontitis. Deteriorated levels of the upper extremities in advanced stages of PD were associated with worse periodontal status and hygiene habits. Quality of life in PD appears to be associated with self-perceived OHRQoL and xerostomia.

Non-Surgical Periodontal Therapy's Influence on Alpha-Synuclein and Inflammatory Marker Levels: A Pilot Study.

Background: Microbial dysbiosis may contribute to alpha-synuclein (α-Syn) homeostasis disruption, yet the burden of inflammatory periodontal infection and its treatment have never been studied in this regard. We aimed to compare the cytokine and α-Syn levels in the saliva and blood of patients with periodontitis who underwent non-surgical periodontal therapy (NSPT) and those of their healthy counterparts. Methods: Periodontal examination and saliva and blood sample collection were carried out in incoming patients at a university clinic. The periodontitis group (PG) received NSPT. The sample collection and periodontal observation were repeated 30 days after. IL-6, IL1-ß and total α-Syn were quantified using immunoassay methods. The periodontal inflamed surface area (PISA) was calculated as a proxy for periodontal inflammation. Results: Eleven participants formed the PG, and there were fifteen healthy controls (HC). At baseline, no correlation between salivary and plasma α-Syn was found. The salivary α-Syn levels revealed a tendency to decrease 30 days after, particularly in the PD cases. The variation in PISA and α-Syn showed significant correlation. Salivary α-Syn correlated negatively with salivary IL-6 levels at both timepoints in the total sample (rho = -0.394 and rho = -0.451) and in the HC (rho = -0.632 and rho = -0.561). Variations in plasma IL-6 and α-Syn were negatively correlated (rho = -0.518) in the healthy participants. Baseline plasma IL1-ß negatively correlated with plasmatic α-Syn at 30 days in the HC (rho = -0.581). Conclusions: Salivary and plasma α-Syn bioavailability operate independently, and periodontal diagnosis was not a confounding factor. Salivary α-Syn levels were significantly affected by NSPT, contrary to plasma levels. These results should be confirmed in future larger and prospective studies.

Revisiting Oral Antiseptics, Microorganism Targets and Effectiveness.

A good oral health status is mostly dependent on good oral hygiene habits, which knowingly impacts systemic health. Although controversial, chemical oral antiseptics can be useful in adjunct use to mechanical dental plaque control techniques in the prevention and management of local and overall health and well-being. This review aims to revisit, gather and update evidence-based clinical indications for the use of the most popular oral antiseptics, considering different types, microorganism targets and effectiveness in order to establish updated clinical recommendations.

Self-Management Ability Questionnaire Validation in Portuguese Adults With Periodontitis.

OBJECTIVES: We aimed to test the psychometric validity of the adapted and translated Self-Management Ability Questionnaire-Short Form (SMAQ-12) to Portuguese. METHODS: The translation and adaptation of the SMAQ-12 followed international guidelines. We included 280 participants with chronic periodontitis from the Department of Periodontology of the Egas Moniz Dental Clinic. Participants completed the Portuguese version of the SMAQ-12 (SMAQ-12-PT), a 12-item scale with 3 conceptual domains (Role Management, Medical Management, and Emotional Management). The validity of the content, its construct and internal consistency, as well as test-retest reliability were used to estimate psychometric properties. RESULTS: The SMAQ-12-PT showed an interclass correlation coefficient value of 0.90, with a 95% confidence interval (0.79-0.95; P < .001) and high reliability (Cronbach alpha coefficient ranging between 0.78 and 0.94). Confirmatory factor analysis revealed adequate model fit, with comparative fit index of 0.853, goodness-of-fit of 0.947, and a 0.052 value of root mean squared error of approximation. CONCLUSIONS: The SMAQ-12-PT was found to be a valid and reliable instrument in the Portuguese population. Disease management representation for the specialty of periodontology and its impact on periodontal schedules and practices should be evaluated in future studies.

Self-Reported Measures of Periodontitis in a Portuguese Population: A Validation Study.

Self-reported questionnaires have been developed and validated in multiple populations as useful tools to estimate the prevalence of periodontitis in epidemiological settings. This study aimed to explore the accuracy of self-reporting for predicting the prevalence of periodontitis in a Portuguese population. The questionnaires were given to patients at a university clinic. Thirteen self-reported questions on periodontal health were gathered in a patient-reported questionnaire. Then, self-reporting responses were validated using full-mouth periodontal examination as a comparison. Multivariable logistic regression was used to analyze sensitivity, specificity, accuracy, precision, and area under the curve-receiver operator characteristic (AUC-ROC). Self-reported answers from 103 participants (58 females and 45 males) were included. Self-reported gum health, loose teeth, tooth appearance, and use of dental floss were associated with different definitions of severe periodontitis. The self-reported questions on "having gum disease," combined with "having gum treatment" and "having lost bone" were the items with higher performance for the 2018 case definition and the 2012 case definition, as well as for each respective severity staging. Categorization of tooth loss was only valuable for the prediction of periodontitis cases according to the 2012 case definition and its severe stage. Multiple self-reporting set-ups showed elevated performance levels for predicting periodontitis in Portuguese patients. These results may pave the way for future epidemiological surveillance programs using self-reporting approaches.

Self-reported periodontitis and C-reactive protein in Parkinson's disease: a cross-sectional study of two American cohorts.

Periodontitis triggers systemic repercussions, such as elevated levels of high-sensitive C-reactive protein (hs-CRP). This has never been studied within Parkinson's Disease (PD). The aim of this study is to compare hs-CRP levels of self-reported periodontitis cases versus cases without periodontitis in PD patients. Data from the National Health and Nutrition Examination Survey (2015-2016 and 2017-2018 waves) were analyzed. PD cases were identified through medication regimens and periodontitis cases through a validated self-report questionnaire. 51 participants were included (24 females, 27 males, with mean age of 62.96 (14.71)). While the self-reported periodontitis group presented elevated levels of circulating hs-CRP (5.36 vs. 1.99 mg/L, p = 0.031), the self-reported without periodontitis group presented higher lymphocyte levels (29.35 vs. 28.03%, p = 0.007). Blood levels of hs-CRP were significantly higher in PD cases with self-reported periodontitis. Apart from the lymphocyte levels, there were no other significant differences according to the self-reported periodontal status. Future studies shall explore this association using clinical measures.

Tooth Loss and Blood Pressure in Parkinson's Disease Patients: An Exploratory Study on NHANES Data.

Objectives: To evaluate tooth loss severity in PD patients and the impact of missing teeth on blood pressure (BP) and glycated hemoglobin (Hba1c) levels. Methods: All adults reporting specific PD medication regimens with complete dental examinations were included from the NHANES 2001 to 2018 databases. Sociodemographic, systolic BP (SBP), diastolic BP (DBP) and Hba1c data were compared according to tooth loss severity, and linear regression analyses on the impact of tooth loss on SBP, DBP and Hba1c levels were conducted. Results: The 214 included participants presented 9.7 missing teeth, 23.8% severe tooth loss and 18.2% total edentulousness. Severe tooth loss cases were significantly older (p < 0.001), had higher smoking prevalence (p = 0.008), chronic medical conditions (p = 0.012) and higher Hba1c (p = 0.001), SBP (p = 0.015) and DBP (p < 0.001) levels. Crude and adjusted linear models revealed a relationship between SBP, DBP and missing teeth; however, age confounded these links (SBP: B = 0.10, SE = 0.16, p < 0.05; DBP: B = 0.16, SE = 0.10, p < 0.05). Tooth loss presented no significant relationship with Hba1c levels. Conclusions: Severe tooth loss is prevalent among PD patients. Blood pressure levels showed a positive linear relationship with the number of missing teeth, although age was a confounding factor. Furthermore, tooth loss and Hba1c levels revealed no significant linear relationship.

The Role of Inflammatory Diet and Vitamin D on the Link between Periodontitis and Cognitive Function: A Mediation Analysis in Older Adults.

Patients suffering from periodontitis are at a higher risk of developing cognitive dysfunction. However, the mediation effect of an inflammatory diet and serum vitamin D levels in this link is unclear. In total, 2062 participants aged 60 years or older with complete periodontal diagnosis and cognitive tests from the National Health and Nutrition Examination Survey (NHANES) 2011-2012 and 2013-2014 were enrolled. The Consortium to Establish a Registry for Alzheimer's disease (CERAD) word learning subtest (WLT) and CERAD delayed recall test (DRT), the animal fluency test (AFT) and the digit symbol substitution test (DSST) was used. Dietary inflammatory index (DII) was computed via nutrition datasets. Mediation analysis tested the effects of DII and vitamin D levels in the association of mean probing depth (PD) and attachment loss (AL) in all four cognitive tests. Periodontitis patients obtained worse cognitive test scores than periodontally healthy individuals. DII was negatively associated with CERAD-WLT, CERAD-DRT, AFT and DSST, and was estimated to mediate between 9.2% and 36.4% of the total association between periodontitis with cognitive dysfunction (p < 0.05). Vitamin D showed a weak association between CERAD-DRT, AFT and DSST and was estimated to between 8.1% and 73.2% of the association between periodontitis and cognitive dysfunction (p < 0.05). The association between periodontitis and impaired cognitive function seems to be mediated both by a proinflammatory dietary load and vitamin D deficiency. Future studies should further explore these mediators in the periodontitis-cognitive decline link.

Relationship between Blood and Standard Biochemistry Levels with Periodontitis in Parkinson's Disease Patients: Data from the NHANES 2011-2012.

People with Parkinson's Disease (PD) are associated with the presence of periodontitis. We aimed to compare blood and standard biochemical surrogates of PD patients diagnosed with periodontitis with PD individuals without periodontitis. This retrospective cohort study used a sample from the National Health and Nutrition Examination Survey (NHANES) 2011-2012 that underwent periodontal diagnosis (n = 3669). PD participants were identified through specific PD reported medications. Periodontitis was defined according to the 2012 case definition, using periodontal examination data provided. Then, we compared blood levels and standard chemical laboratory profiles of PD patients according to the presence of periodontitis. Multivariable regression was used to explore this dataset and identify relevant variables towards the presence of periodontitis. According to the medication report, 37 participants were eligible, 29 were secure and 8 were unsecure PD medications regimens. Overall, PD cases with periodontitis presented increased levels of White Blood Cells (WBC) (p = 0.002), Basophils (p = 0.045) and Segmented neutrophils (p = 0.009), and also, lower levels of Total Bilirubin (p = 0.018). In the PD secure medication group, a significant difference was found for WBC (p = 0.002) and Segmented neutrophils (p = 0.002) for the periodontitis group. Further, WBC might be a discriminating factor towards periodontitis in the global sample. In the secure PD medication, we found gender, segmented neutrophils and Vitamin D2 to be potential discriminative variables towards periodontitis. Thus, periodontitis showed association with leukocyte levels alterations in PD patients, and therefore with potential systemic changes and predictive value. Furthermore, Vitamin D2 and gender showed to be associated with periodontitis in with secure medication for PD. Future studies should assess in more detail the potential systemic repercussion of the presence of periodontitis in PD patients.