Blood and saliva SARS-CoV-2 antibody levels in self-collected dried spot samples.

We examined the usefulness of dried spot blood and saliva samples in SARS-CoV-2 antibody analyses. We analyzed 1231 self-collected dried spot blood and saliva samples from healthcare workers. Participants filled in a questionnaire on their COVID-19 exposures, infections, and vaccinations. Anti-SARS-CoV-2 IgG, IgA, and IgM levels were determined from both samples using the GSP/DELFIA method. The level of exposure was the strongest determinant of all blood antibody classes and saliva IgG, increasing as follows: (1) no exposure (healthy, non-vaccinated), (2) exposed, (3) former COVID-19 infection, (4) one vaccination, (5) two vaccinations, and (6) vaccination and former infection. While the blood IgG assay had a 99.5% sensitivity and 75.3% specificity to distinguish participants with two vaccinations from all other types of exposure, the corresponding percentages for saliva IgG were 85.3% and 65.7%. Both blood and saliva IgG-seropositivity proportions followed similar trends to the exposures reported in the questionnaires. Self-collected dry blood and saliva spot samples combined with the GSP/DELFIA technique comprise a valuable tool to investigate an individual's immune response to SARS-CoV-2 exposure or vaccination. Saliva IgG has high potential to monitor vaccination response wane, since the sample is non-invasive and easy to collect.

Periodontitis and cardiometabolic disorders: The role of lipopolysaccharide and endotoxemia.

Lipopolysaccharide is a virulence factor of gram-negative bacteria with a crucial importance to the bacterial surface integrity. From the host's perspective, lipopolysaccharide plays a role in both local and systemic inflammation, activates both innate and adaptive immunity, and can trigger inflammation either directly (as a microbe-associated molecular pattern) or indirectly (by inducing the generation of nonmicrobial, danger-associated molecular patterns). Translocation of lipopolysaccharide into the circulation causes endotoxemia, which is typically measured as the biological activity of lipopolysaccharide to induce coagulation of an aqueous extract of blood cells of the assay. Apparently healthy subjects have a low circulating lipopolysaccharide activity, since it is neutralized and cleared rapidly. However, chronic endotoxemia is involved in the pathogenesis of many inflammation-driven conditions, especially cardiometabolic disorders. These include atherosclerotic cardiovascular diseases, obesity, liver diseases, diabetes, and metabolic syndrome, where endotoxemia has been recognized as a risk factor. The main source of endotoxemia is thought to be the gut microbiota. However, the oral dysbiosis in periodontitis, which is typically enriched with gram-negative bacterial species, may also contribute to endotoxemia. As endotoxemia is associated with an increased risk of cardiometabolic disorders, lipopolysaccharide could be considered as a molecular link between periodontal microbiota and cardiometabolic diseases.

Aggregatibacter actinomycetemcomitans serotypes associate with periodontal and coronary artery disease status.

AIM: We investigated the association between the Aggregatibacter actinomycetemcomitans serotypes, periodontal status and coronary artery disease (CAD). MATERIALS AND METHODS: The study population included 497 patients who underwent coronary angiography, and clinical oral examination. Quantitative polymerase chain reaction assays were designed to identify the serotypes from saliva samples. RESULTS: Aggregatibacter actinomycetemcomitans serotype frequencies were as follows: serotype "c" 35.7%, "b" 28.6%, "a" 26.2%, "e" 7.1%, "d" 2.4% and "f" 0%. The subjects with a detectable serotype had less teeth and higher bleeding on probing than those with no serotype. Serotypes "b" and "c" associated with periodontal probing depths and periodontal inflammatory burden. The saliva and subgingival bacterium quantities and serum antibody levels against A. actinomycetemcomitans were highest in patients harbouring serotype "c." Serotypes "b" and "c" were most frequent (59.3%) in patients with CAD (p = .040), and they associated with the risk of stable CAD with an odds ratio of 2.67 (95% confidence interval 1.06-7.44). Also, the severity of CAD (p = .018) associated with serotypes "b" and "c." CONCLUSIONS: Aggregatibacter actinomycetemcomitans serotypes "b" and "c" associate with both periodontal and CAD status. Detectable serotypes associate with the quantity and the serology of the bacterium emphasizing both local and systemic effect of the A. actinomycetemcomitans serotypes.

Matrix metalloproteinase 8 degrades apolipoprotein A-I and reduces its cholesterol efflux capacity.

Various cell types in atherosclerotic lesions express matrix metalloproteinase (MMP)-8. We investigated whether MMP-8 affects the structure and antiatherogenic function of apolipoprotein (apo) A-I, the main protein component of HDL particles. Furthermore, we studied serum lipid profiles and cholesterol efflux capacity in MMP-8-deficient mouse model. Incubation of apoA-I (28 kDa) with activated MMP-8 yielded 22 kDa and 25 kDa apoA-I fragments. Mass spectrometric analyses revealed that apoA-I was cleaved at its carboxyl-terminal part. Treatment of apoA-I and HDL with MMP-8 resulted in significant reduction (up to 84%, P < 0.001) in their ability to facilitate cholesterol efflux from cholesterol-loaded THP-1 macrophages. The cleavage of apoA-I by MMP-8 and the reduction in its cholesterol efflux capacity was inhibited by doxycycline. MMP-8-deficient mice had significantly lower serum triglyceride (TG) levels (P = 0.003) and larger HDL particles compared with wild-type (WT) mice. However, no differences were observed in the apoA-I levels or serum cholesterol efflux capacities between the mouse groups. Proteolytic modification of apoA-I by MMP-8 may impair the first steps of reverse cholesterol transport, leading to increased accumulation of cholesterol in the vessel walls. Eventually, inhibition of MMPs by doxycycline may reduce the risk for atherosclerotic vascular diseases.

Salivary biomarkers of bacterial burden, inflammatory response, and tissue destruction in periodontitis.

AIM: Chronic periodontitis has an episodic and multifactorial character, with fluctuations in bacterial burden, inflammatory response, and tissue destruction. We investigated the association of selected salivary biomarkers with periodontal parameters and validated the use of a novel salivary diagnostic approach, the cumulative risk score (CRS), in detection of periodontitis in subjects with angiographically verified coronary artery disease diagnosis. MATERIALS AND METHODS: The concentrations of matrix metalloproteinase (MMP)-8, interleukin (IL)-1ß, and Porphyromonas gingivalis were analysed from saliva of 493 subjects. The subjects participated in a detailed clinical and radiographic oral examination. The CRS index, combining the three salivary biomarkers, was calculated for each subject. RESULTS: High salivary concentrations of MMP-8, IL-1ß, and P. gingivalis were associated with deepened periodontal pockets and alveolar bone loss, and MMP-8 and IL-1ß with bleeding on probing. The CRS index had a stronger association with moderate to severe periodontitis (OR 6.13; 95% CI 3.11-12.09) than any of the markers alone. CONCLUSIONS: Salivary concentrations of MMP-8, IL-1ß, and P. gingivalis are associated with various clinical and radiographic measures of periodontitis. The CRS index, combining the three salivary biomarkers, is associated with periodontitis more strongly than any of the markers alone regardless of the coronary artery disease status of the patients.

Subantimicrobial-dose doxycycline treatment increases serum cholesterol efflux capacity from macrophages.

OBJECTIVE: Subantimicrobial-dose doxycycline (SDD) treatment has been reported to reduce the severity of chronic inflammation and to increase serum high-density lipoprotein cholesterol. In a double-blind, placebo-controlled clinical trial, we determined whether SDD affects the ability of serum to facilitate cholesterol removal from macrophages. METHODS: Forty-five postmenopausal osteopenic women with periodontitis were randomly assigned to take placebo (n = 26) or doxycycline hyclate (20 mg, n = 19) tablets twice daily for 2 years. Serum samples were collected at baseline, 1-, and 2-year appointments. The cholesterol efflux capacity of serum from cultured human macrophages (THP-1) was measured. RESULTS: SDD subjects demonstrated a significant increase in serum-mediated cholesterol efflux from macrophages at both time points compared to baseline (p < 0.04 for each). Mean cholesterol efflux levels over the first year of follow-up were 3.0 percentage points (unit change) higher among SDD subjects compared to placebo subjects (p = 0.010), while there was no significant difference in 2-year changes. There were no significant differences in the changes of apolipoprotein A-I, apolipoprotein A-II, or serum amyloid A levels between the groups. CONCLUSIONS: Our results suggest that SDD treatment may reduce the risk of cardiovascular disease in this patient group by increasing the cholesterol efflux capacity of serum.

Common complement factor H polymorphisms are linked with periodontitis in elderly patients.

BACKGROUND: In our recent genome-wide association study, we found that genetic polymorphisms in the complement factor H (CFH) gene and S100A gene region are strongly associated with serum matrix metalloproteinase 8 (MMP-8) concentration and the release of MMP-8 from neutrophils. As MMP-8 is centrally involved in the pathogenesis of periodontitis, we aimed to evaluate the presence of genetic polymorphisms of S100A8/A9/A12, MMP8, and CFH in periodontitis. In addition, we studied whether polymorphisms of these genes affect the concentrations of S100A8, S100A12, MMP-8, or complement activation marker in saliva. METHODS: We genotyped four single-nucleotide polymorphisms (SNPs, rs1560833 in S100A8/A9/A12, rs11225395 in MMP8, rs800292 in CFH, and rs1061170 in CFH) and measured salivary concentrations of S100A8, S100A12, MMP-8, and terminal complement complex (TCC) in the Parogene cohort (n = 508). The cohort was composed of patients with an indication to coronary angiography and all underwent a clinical and radiographic oral examination. RESULTS: CFH polymorphisms rs800292 and rs1061170 were associated with periodontal parameters. None of the polymorphisms showed association with salivary proteins. However, salivary concentrations of S100A8, S100A12, MMP-8, and TCC were strongly associated with the number of periodontal pockets and alveolar bone loss. CONCLUSION: Interestingly, genetic variants of CFH, MMP8, and S100A8/A9/A12 gene regions did not affect salivary levels of measured proteins. However, saliva levels of S100A8, S100A12, MMP-8, and TCC, and CFH polymorphisms were associated with clinical and radiographic signs of periodontitis. Our study further supports the observations that any dysregulation of complement may increase the risk of inflammatory disorders, such as periodontitis.

Effect of RNA quality to SARS-CoV-2 RT-qPCR detection from saliva.

Saliva is an alternative sample material to nasopharyngeal swab in SARS-CoV-2 diagnostics. We investigated possible aspects to improve the reliability of SARS-CoV-2 detection from saliva. Saliva was collected from asymptomatic healthy subjects (n=133) and COVID-19 patients (n=9). SARS-CoV-2 detection was performed with quantitative reverse-transcriptase PCR (RT-qPCR) with two viral and one host target serving as an internal control. The use of internal control revealed that in the first RT-qPCR run 25-30 % of assays failed. The failure is associated with poor RNA quality. When the amount of RNA was cut down to half from the original amount, the performance of RT-qPCR was greatly enhanced (95 % of the assays succeeded). The quality of RNA was not affected by the use of different nucleic acid stabilizing buffers. Our study showed that saliva is suitable material for RT-qPCR based SARS-CoV-2 diagnostics, but the use of internal control is essential to distinguish the true negative samples from failed assays.

Non-antibacterial tetracyclines modulate mediators of periodontitis and atherosclerotic cardiovascular disease: a mechanistic link between local and systemic inflammation.

Periodontitis, one of the most common chronic inflammatory diseases afflicting man, is increasingly being recognized as a risk factor for atherosclerotic cardiovascular disease (ASCVD). Non-antimicrobial tetracyclines are known to have inhibitory effects on inflammatory mediators and effector molecules, including cytokines and matrix metalloproteinases (MMPs), associated with both diseases. In this paper, we discuss the evidence that doxycycline and related non-antibiotic chemically modified tetracyclines (e.g., CMT-3) can effectively reduce cytokine (TNF-α, IL-6, and MCP-1) production by human mononuclear inflammatory cells when stimulated either by endotoxin (LPS) or by a complex of C-reactive protein/oxidized LDL cholesterol relevant to the pathogenesis of periodontal disease and ASCVD, respectively. This inhibition by tetracycline compounds appears to be mediated at least in part by a suppression of the phosphorylation/activation of the NFκB cell signaling pathway. We are currently conducting clinical trials on patients who exhibit both diseases, and our preliminary data suggest that virtually all acute coronary syndrome (ACS) patients exhibit moderate-to-severe periodontitis, a higher incidence of this oral inflammatory disease than that seen in the population at large. In other studies, a non-antimicrobial formulation of doxycycline (SDD) has been found to dramatically reduce hsCRP, IL-6 and MMP-9 levels in plasma of ACS patients, and SDD has also been found to significantly increase serum levels of both cardio-protective HDL cholesterol and its core molecule apolipoprotein A-I in ASCVD-vulnerable patients with periodontitis. Our current research suggests that one mechanism involved may be the ability of SDD to inhibit MMP-mediated HDL loss by protecting apolipoprotein A-I from proteinase attack. These pleiotropic mechanisms of non-antimicrobial tetracyclines provide significant therapeutic potential to treat chronic inflammatory diseases including both periodontitis and ASCVD.

Endotoxemia is associated with an adverse metabolic profile.

Our aim was to analyze whether endotoxemia, i.e. translocation of LPS to circulation, is reflected in the serum metabolic profile in a general population and in participants with cardiometabolic disorders. We investigated three Finnish cohorts separately and in a meta-analysis (n = 7178), namely population-based FINRISK97, FinnTwin16 consisting of young adult twins, and Parogene, a random cohort of cardiac patients. Endotoxemia was determined as serum LPS activity and metabolome by an NMR platform. Potential effects of body mass index (BMI), smoking, metabolic syndrome (MetS), and coronary heart disease (CHD) status were considered. Endotoxemia was directly associated with concentrations of VLDL, IDL, LDL, and small HDL lipoproteins, VLDL particle diameter, total fatty acids (FA), glycoprotein acetyls (GlycA), aromatic and branched-chain amino acids, and Glc, and inversely associated with concentration of large HDL, diameters of LDL and HDL, as well as unsaturation degree of FAs. Some of these disadvantageous associations were significantly stronger in smokers and subjects with high BMI, but did not differ between participants with different CHD status. In participants with MetS, however, the associations of endotoxemia with FA parameters and GlycA were particularly strong. The metabolic profile in endotoxemia appears highly adverse, involving several inflammatory characters and risk factors for cardiometabolic disorders.

Systemic Antibiotics Influence Periodontal Parameters and Oral Microbiota, But Not Serological Markers.

The use of systemic antibiotics may influence the oral microbiota composition. Our aim was to investigate in this retrospective study whether the use of prescribed antibiotics associate with periodontal status, oral microbiota, and antibodies against the periodontal pathogens. The Social Insurance Institution of Finland Data provided the data on the use of systemic antibiotics by record linkage to purchased medications and entitled reimbursements up to 1 year before the oral examination and sampling. Six different classes of antibiotics were considered. The Parogene cohort included 505 subjects undergoing coronary angiography with the mean (SD) age of 63.4 (9.2) years and 65% of males. Subgingival plaque samples were analysed using the checkerboard DNA-DNA hybridisation. Serum and saliva antibody levels to periodontal pathogens were analysed with immunoassays and lipopolysaccharide (LPS) activity with the LAL assay. Systemic antibiotics were prescribed for 261 (51.7%) patients during the preceding year. The mean number of prescriptions among them was 2.13 (range 1-12), and 29.4% of the prescriptions were cephalosporins, 25.7% penicillins, 14.3% quinolones, 12.7% macrolides or lincomycin, 12.0% tetracycline, and 5.8% trimethoprim or sulphonamides. In linear regression models adjusted for age, sex, current smoking, and diabetes, number of antibiotic courses associated significantly with low periodontal inflammation burden index (PIBI, p < 0.001), bleeding on probing (BOP, p = 0.006), and alveolar bone loss (ABL, p = 0.042). Cephalosporins associated with all the parameters. The phyla mainly affected by the antibiotics were Bacteroidetes and Spirochaetes. Their levels were inversely associated with the number of prescriptions (p = 0.010 and p < 0.001) and directly associated with the time since the last prescription (p = 0.019 and p < 0.001). Significant inverse associations were observed between the number of prescriptions and saliva concentrations of Prevotella intermedia, Tannerella forsythia, and Treponema denticola and subgingival bacterial amounts of Porphyromonas gingivalis, P. intermedia, T. forsythia, and T. denticola. Saliva or serum antibody levels did not present an association with the use of antibiotics. Both serum (p = 0.031) and saliva (p = 0.032) LPS activity was lower in patients having any antibiotic course less than 1 month before sampling. Systemic antibiotics have effects on periodontal inflammation and oral microbiota composition, whereas the effects on host immune responses against the periodontal biomarker species seem unchanged.

Genetic Profile of Endotoxemia Reveals an Association With Thromboembolism and Stroke.

Background Translocation of lipopolysaccharide from gram-negative bacteria into the systemic circulation results in endotoxemia. In addition to acute infections, endotoxemia is detected in cardiometabolic disorders, such as cardiovascular diseases and obesity. Methods and Results We performed a genome-wide association study of serum lipopolysaccharide activity in 11 296 individuals from 6 different Finnish study cohorts. Endotoxemia was measured by limulus amebocyte lysate assay in the whole population and by 2 other techniques (Endolisa and high-performance liquid chromatography/tandem mass spectrometry) in subpopulations. The associations of the composed genetic risk score of endotoxemia and thrombosis-related clinical end points for 195 170 participants were analyzed in FinnGen. Lipopolysaccharide activity had a genome-wide significant association with 741 single-nucleotide polymorphisms in 5 independent loci, which were mainly located at genes affecting the contact activation of the coagulation cascade and lipoprotein metabolism and explained 1.5% to 9.2% of the variability in lipopolysaccharide activity levels. The closest genes included KNG1, KLKB1, F12, SLC34A1, YPEL4, CLP1, ZDHHC5, SERPING1, CBX5, and LIPC. The genetic risk score of endotoxemia was associated with deep vein thrombosis, pulmonary embolism, pulmonary heart disease, and venous thromboembolism. Conclusions The biological activity of lipopolysaccharide in the circulation (ie, endotoxemia) has a small but highly significant genetic component. Endotoxemia is associated with genetic variation in the contact activation pathway, vasoactivity, and lipoprotein metabolism, which play important roles in host defense, lipopolysaccharide neutralization, and thrombosis, and thereby thromboembolism and stroke.

Immunological and Microbiological Profiling of Cumulative Risk Score for Periodontitis.

The cumulative risk score (CRS) is a mathematical salivary diagnostic model to define an individual's risk of having periodontitis. In order to further validate this salivary biomarker, we investigated how periodontal bacteria, lipopolysaccharide (LPS), and systemic and local host immune responses relate to CRS. Subgingival plaque, saliva, and serum samples collected from 445 individuals were used in the analyses. Plaque levels of 28 microbial species, especially those of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, and Tannerella forsythia, and serum and salivary levels of IgA and IgG against these five species were determined. Additionally, LPS activity was measured. High CRS associated strongly with all IgA/IgG antibody and LPS levels in saliva, whereas in serum the associations were not that obvious. In the final logistic regression model, the best predictors of high CRS were saliva IgA burden against the five species (OR 7.04, 95% CI 2.25-22.0), IgG burden (3.79, 1.78-8.08), LPS (2.19, 1.38-3.47), and the sum of 17 subgingival Gram-negative species (6.19, 2.10-18.3). CRS is strongly associated with microbial biomarker species of periodontitis and salivary humoral immune responses against them.

Saliva and Serum Immune Responses in Apical Periodontitis.

Apical periodontitis is an inflammatory reaction at the apex of an infected tooth. Its microbiota resembles that of marginal periodontitis and may induce local and systemic antibodies binding to bacteria- and host-derived epitopes. Our aim was to investigate the features of the adaptive immune response in apical periodontitis. The present Parogene cohort (n = 453) comprises patients with cardiac symptoms. Clinical and radiographic oral examination was performed to diagnose apical and marginal periodontitis. A three-category endodontic lesion score was designed. Antibodies binding to the bacteria- and host-derived epitopes were determined from saliva and serum, and bacterial compositions were examined from saliva and subgingival samples. The significant ORs (95% CI) for the highest endodontic scores were observed for saliva IgA and IgG to bacterial antigens (2.90 (1.01-8.33) and 4.91 (2.48-9.71)/log10 unit), saliva cross-reacting IgG (2.10 (1.48-2.97)), serum IgG to bacterial antigens (4.66 (1.22-10.1)), and Gram-negative subgingival species (1.98 (1.16-3.37)). In a subgroup without marginal periodontitis, only saliva IgG against bacterial antigens associated with untreated apical periodontitis (4.77 (1.05-21.7)). Apical periodontitis associates with versatile adaptive immune responses against both bacterial- and host-derived epitopes independently of marginal periodontitis. Saliva immunoglobulins could be useful biomarkers of oral infections including apical periodontitis-a putative risk factor for systemic diseases.

Salivary biomarkers in association with periodontal parameters and the periodontitis risk haplotype.

Genetic factors play a role in periodontitis. Here we examined whether the risk haplotype of MHC class III region BAT1-NFKBIL1-LTA and lymphotoxin-α polymorphisms associate with salivary biomarkers of periodontal disease. A total of 455 individuals with detailed clinical and radiographic periodontal health data were included in the study. A 610 K genotyping chip and a Sequenom platform were used in genotyping analyses. Phospholipid transfer protein activity, concentrations of lymphotoxin-α, IL-8 and myeloperoxidase, and a cumulative risk score (combining Porphyromonas gingivalis, IL-1ß and matrix metalloproteinase-8) were examined in saliva samples. Elevated IL-8 and myeloperoxidase concentrations and cumulative risk scores associated with advanced tooth loss, deepened periodontal pockets and signs of periodontal inflammation. In multiple logistic regression models adjusted for periodontal parameters and risk factors, myeloperoxidase concentration (odds ratio (OR); 1.37, P = 0.007) associated with increased odds for having the risk haplotype and lymphotoxin-α concentration with its genetic variants rs2857708, rs2009658 and rs2844482. In conclusion, salivary levels of IL-8, myeloperoxidase and cumulative risk scores associate with periodontal inflammation and tissue destruction, while those of myeloperoxidase and lymphotoxin-α associate with genetic factors as well.

The inherent accuracy of 1H NMR spectroscopy to quantify plasma lipoproteins is subclass dependent.

Proton NMR spectroscopy as a means to quantify lipoprotein subclasses has received wide clinical interest. The experimental part is a fast routine procedure that contrasts favourably to other lipoprotein measurement protocols. The difficulties in using (1)H NMR, however, are in uncovering the subclass specific information from the overlapping data. The NMR-based quantification has been evaluated only in relation to biochemical measures, thereby leaving the inherent capability of NMR rather vague due to biological variation and diversity among the biochemical experiments. Here we will assess the use of (1)H NMR spectroscopy of plasma per se. This necessitates data for which the inherent parameters, namely the shapes and areas of the (1)H NMR signals of the subclasses are available. This was achieved through isolation and (1)H NMR experiments of 11 subclasses--VLDL1, VLDL2, IDL, LDL1, LDL2, LDL3, HDL(2b), HDL(2a), HDL(3a), HDL(3b) and HDL(3c)--and the subsequent modelling of the spectra. The subclass models were used to simulate biochemically representative sets of spectra with known subclass concentrations. The spectral analyses revealed 10-fold differences in the quantification accuracy of different subclasses by (1)H NMR. This finding has critical significance since the usage of (1)H NMR methodology in the clinical arena is rapidly increasing.

Genetic Variants Contributing to Circulating Matrix Metalloproteinase 8 Levels and Their Association With Cardiovascular Diseases: A Genome-Wide Analysis.

BACKGROUND: Matrix metalloproteinase 8 (MMP-8) is a proinflammatory enzyme expressed mainly by neutrophils. Elevated serum and plasma concentrations of MMP-8 are associated with the risk for and outcome of cardiovascular diseases (CVDs). The origin of circulating MMP-8 is not completely clear. METHODS AND RESULTS: We performed a genome-wide association study of serum MMP-8 levels in 2 populations comprising altogether 6049 individuals. Moreover, we studied whether MMP-8-associated variants are linked to increased risk of CVDs and overall mortality in >20 000 subjects. The strongest association with serum MMP-8 was found in locus 1q31.3, containing the gene for complement factor H (lead single nucleotide polymorphism: rs800292; P=2.4×10-35). In functional experiments, activation of the alternative pathway of complement in the carriers of rs800292 minor allele (Ile62 in factor H) led to decreased release of MMP-8 from neutrophils compared with the major allele (Val62 in factor H). Another association was detected in 1q21.3, containing genes S100A8, S100A9, and S100A12 (strongest association: rs1560833; P=5.3×10-15). The minor allele of rs1560833 was inversely associated with CVD (odds ratio [95% confidence interval]: 0.90 [0.82-0.99]; P=0.032) and the time to incident CVD event (hazard ratio [95% confidence interval]: 0.91 [0.84-0.99]; P=0.032) in men but not in women. CONCLUSIONS: According to our results, the activation of the alternative pathway of the complement system strongly contributes to serum MMP-8 concentration. Genetic polymorphism in S100A9-S100A12-S100A8 locus affects serum and plasma MMP-8 and shows a suggestive association with the risk of CVDs. Our results show that genetic variation determines a significant portion of circulating MMP-8 concentrations.

Quantitative PCR analysis of salivary pathogen burden in periodontitis.

Our aim was to investigate the value of salivary concentrations of four major periodontal pathogens and their combination in diagnostics of periodontitis. The Parogene study included 462 dentate subjects (mean age 62.9 ± 9.2 years) with coronary artery disease (CAD) diagnosis who underwent an extensive clinical and radiographic oral examination. Salivary levels of four major periodontal bacteria were measured by quantitative real-time PCR (qPCR). Median salivary concentrations of Porphyromonas gingivalis, Tannerella forsythia, and Prevotella intermedia, as well as the sum of the concentrations of the four bacteria, were higher in subjects with moderate to severe periodontitis compared to subjects with no to mild periodontitis. Median salivary Aggregatibacter actinomycetemcomitans concentrations did not differ significantly between the subjects with no to mild periodontitis and subjects with moderate to severe periodontitis. In logistic regression analysis adjusted for age, gender, diabetes, and the number of teeth and implants, high salivary concentrations of P. gingivalis, T. forsythia, and P. intermedia were significantly associated with moderate to severe periodontitis. When looking at different clinical and radiographic parameters of periodontitis, high concentrations of P. gingivalis and T. forsythia were significantly associated with the number of 4-5 mm periodontal pockets, ≥6 mm pockets, and alveolar bone loss (ABL). High level of T. forsythia was associated also with bleeding on probing (BOP). The combination of the four bacteria, i.e., the bacterial burden index, was associated with moderate to severe periodontitis with an odds ratio (OR) of 2.40 (95% CI 1.39-4.13). When A. actinomycetemcomitans was excluded from the combination of the bacteria, the OR was improved to 2.61 (95% CI 1.51-4.52). The highest OR 3.59 (95% CI 1.94-6.63) was achieved when P. intermedia was further excluded from the combination and only the levels of P. gingivalis and T. forsythia were used. Salivary diagnostics of periodontitis has potential especially in large-scale population studies and health promotion. The cumulative strategy appears to be useful in the analysis of salivary bacteria as markers of periodontitis.

1H NMR metabonomics of plasma lipoprotein subclasses: elucidation of metabolic clustering by self-organising maps.

(1)H NMR spectra of plasma are known to provide specific information on lipoprotein subclasses in the form of complex overlapping resonances. A combination of (1)H NMR and self-organising map (SOM) analysis was applied to investigate if automated characterisation of subclass-related metabolic interactions can be achieved. To reliably assess the intrinsic capability of (1)H NMR for resolving lipoprotein subclass profiles, sum spectra representing the pure lipoprotein subclass part of actual plasma were simulated with the aid of experimentally derived model signals for 11 distinct lipoprotein subclasses. Two biochemically characteristic categories of spectra, representing normolipidaemic and metabolic syndrome status, were generated with corresponding lipoprotein subclass profiles. A set of spectra representing a metabolic pathway between the two categories was also generated. The SOM analysis, based solely on the aliphatic resonances of these simulated spectra, clearly revealed the lipoprotein subclass profiles and their changes. Comparable SOM analysis in a group of 69 experimental (1)H NMR spectra of serum samples, which according to biochemical analyses represented a wide range of lipoprotein lipid concentrations, corroborated the findings based on the simulated data. Interestingly, the choline-N(CH(3))(3) region seems to provide more resolved clustering of lipoprotein subclasses in the SOM analyses than the methyl-CH(3) region commonly used for subclass quantification. The results illustrate the inherent suitability of (1)H NMR metabonomics for automated studies of lipoprotein subclass-related metabolism and demonstrate the power of SOM analysis in an extensive and representative case of (1)H NMR metabonomics.