Salivary inflammatory biomarkers and glycated haemoglobin among patients with type 2 diabetic mellitus

Evaluation of salivary interleukin-17 and developmental endothelial locus-1 in patients with periodontitis with and without type 2 diabetes mellitus

BACKGROUND

Bidirectional positive relationship between periodontitis and type 2 diabetes mellitus (T2DM) has been recognized, interleukin 17 (IL-17) and developmental endothelial locus-1 (Del-1) are proposed to play roles in periodontitis and T2DM. This study aims to investigate the association of IL-17 and Del-1 in patients with periodontitis with and without T2DM by measuring their salivary levels.

METHODS

A total of 80 participants were enrolled in a cross-sectional study and divided into healthy (H, n = 27), periodontitis (P, n = 29) and periodontitis with diabetes (PDM, n = 24) groups based on their periodontal and diabetic examination results. Periodontal parameters (plaque index [PI], bleeding on probing [BOP], probing depth [PD], and clinical attachment level [CAL]) as well as diabetic parameters (fasting plasma glucose [FG] and glycated hemoglobin [HbA1c]) were documented and unstimulated saliva was collected. Salivary IL-1β, active-matrix metalloproteinase-8 (aMMP-8), tumor necrosis factor-α (TNF-α), IL-6, IL-8, IL-17, and Del-1 were determined through enzyme-linked immunosorbent assay (ELISA) and their relationships with periodontal and diabetic parameters were examined.

RESULTS

The periodontitis and periodontitis with diabetes groups showed significantly higher levels of IL-17 and lower levels of Del-1 compared with healthy group. The periodontitis with diabetes group exhibited higher levels of IL-17 and lower levels of Del-1 compared with the periodontitis group. After correlation analysis, there were significant correlations between salivary IL-17 and Del-1 and clinical parameters, IL-17 and Del-1 were correlated with PD (r = 0.36, -0.39, p < 0.01), CAL (r = 0.40, -0.42, p < 0.01) and BOP (r = 0.35, -0.37, p < 0.01), they were correlated with FG (r = 0.26, -0.25, p < 0.05) and HbA1c (r = 0.28, -0.40, p < 0.05). Positive relationships were observed between IL-17 and IL-1β and between IL-17 and aMMP-8 (r = 0.80, 0.77, p < 0.01), while Del-1 exhibited negative correlations with IL-1β and aMMP-8 (r = 0.59, 0.69 p < 0.01). Comparison between IL-17 and Del-1 confirmed an inverse relationship (r = -0.71, p < 0.01). Salivary Del-1 levels in the older group were lower compared with young group across the H, P and PDM groups, although these differences were not statistically significant (p > 0.05).

CONCLUSIONS

Salivary IL-17 and Del-1 levels in the periodontitis with diabetes group showed significant changes compared with the periodontitis group, they exhibited an inverse relationship and were both correlated with periodontal parameters (PD, CAL, and BOP) and diabetic parameters (FG and HbA1c).

PLAIN LANGUAGE SUMMARY

Periodontitis and type 2 diabetes mellitus (T2DM) are two common diseases all over the world, some inflammatory mediators (interleukin 17 [IL-17] and developmental endothelial locus-1 [Del-1]) regulate neutrophil production, recruitment and clearance when the body becomes infected and believed to be involved in the progress of diseases of periodontitis and diabetes. In this study, we enrolled healthy subjects, patients with periodontitis, patients with periodontitis and diabetes. We performed dental examinations and evaluated their blood glucose levels, collected their saliva, and detected IL-17 and Del-1 levels in their saliva. We found both patients with periodontitis and patients with periodontitis and diabetes showed higher IL-17 levels and lower Del-1 levels compared with healthy subjects. Patients with periodontitis and diabetes showed higher IL-17 levels and lower Del-1 levels compared with patients with periodontitis. Salivary IL-17 and Del-1 levels were both correlated with dental examination results and blood glucose levels, and salivary IL-17 and Del-1 displayed an inverse relationship.

Exploring Saliva as a Sample for Non-Invasive Glycemic Monitoring in Diabetes: A Scoping Review

Background/Objectives: Diabetes mellitus is characterized by a dysregulated glucose metabolism, necessitating frequent and often invasive monitoring techniques for its effective management. Saliva, a non-invasive and readily accessible biofluid, has been proposed as a potential alternative for glycemic monitoring due to its biochemical correlation with blood glucose levels. This scoping review aims to evaluate the evidence regarding the use of salivary glucose as a biomarker to track glycemic changes in diabetic populations. Methods: This study adhered to the Joanna Briggs Institute guidelines and the PRISMA Extension for Scoping Reviews. A literature search was performed across the PubMed, Scopus, and Web of Science databases, supplemented by manual searches. Results: A total of fifty-seven studies were included, representing populations affected by type 1 diabetes (T1D), type 2 diabetes (T2D), and gestational diabetes (GD). The findings indicated consistent positive correlations between the salivary and blood glucose levels in most studies, although there were significant variations in the sensitivity, specificity, and methodological approaches. Salivary glucose showed promise as a complementary biomarker for glycemic monitoring, particularly due to its non-invasive nature. Conclusions: Challenges such as variability in salivary composition, the absence of standardized collection protocols, and the limited availability of portable devices were noted. This review highlights the potential of saliva as an adjunct sample for diabetes management while stressing the need for further research to bridge existing gaps.

The Role of Oral Biomarkers in the Assessment of Noncommunicable Diseases

Background/Objectives: Oral biomarkers have gained attention as non-invasive tools for assessing systemic diseases due to their potential to reflect physiological and pathological conditions. This review aims to explore the role of oral biomarkers in diagnosing and monitoring systemic diseases, emphasizing their diagnostic relevance and predictive capabilities in clinical practice. Methods: This narrative review synthesizes the current literature on biochemical, immunological, genetic, and microbiological oral biomarkers, with a focus on their sources, types, and clinical applications. Key studies were analyzed to identify associations between oral biomarkers and systemic diseases such as cardiovascular diseases, type 2 diabetes mellitus, autoimmune disorders, and cancers. Results: Oral fluids, including saliva and gingival crevicular fluid, contain diverse biomarkers such as matrix metalloproteinases, cytokines, and genetic indicators. These markers have demonstrated potential in diagnosing and monitoring systemic conditions. Among others, elevated levels of salivary glucose and inflammatory cytokines correlate with diabetes progression, while vascular endothelial growth factor (VEGF) and salivary C-reactive protein might be applicable as indicators for periodontal disease and cardiovascular risk. Additionally, salivary biomarkers like amyloid-beta and tau are promising in detecting neurodegenerative disorders. Conclusions: Oral biomarkers might represent a transformative and point-of-care approach to the early management of systemic diseases; however, challenges in measurement variability, standardization, and validation remain.

Salivary features of periodontitis and gingivitis in type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is associated with cellular abnormalities, tissue and organ dysfunctions, and periodontitis. This investigation examined the relationship between the oral microbiome and salivary biomarkers in T2DM patients with or without periodontitis. This cohort (35-80 years) included systemically healthy non-periodontitis (NP; n = 31), T2DM without periodontitis (DWoP; n = 32) and T2DM with periodontitis (DWP; n = 29). The oral microbiome [Operational Taxonomic Units (OTUs)] (16 s rRNA sequencing) and targeted host salivary biomarkers (immunoassays) were assessed. We identified 47 OTUs that were significantly different in abundance between NP samples and any disease subset or between disease subgroups. The most unique microbiome patterns were observed in the DWP group. Differences in genera/species abundance were also observed when T2DM patients were stratified by extent of periodontal inflammation and disease (i.e., generalized versus localized gingivitis/periodontitis). Salivary biomarkers showed significant elevations in MMP-8, MMP-9, resistin, IL-1β, IL-6, IFNα, and BAFF (THFSR13b) comparing generalized to localized periodontitis. Salivary analytes showed significant positive correlations with specific microbiome members, predominantly in DWP patients. Odds ratio analyses reinforced that a panel of biologic markers (IL-6, MMP-8) and bacteria (e.g., Bacteroidetes, Fusobacteria, Spirochaetes) discriminated the severity and extent of periodontal disease in this diabetic population.

Prospecting Specific Protein Patterns for High Body Mass Index (BMI), Metabolic Syndrome and Type 2 Diabetes in Saliva and Blood Plasma From a Brazilian Population

PURPOSE

Obesity and its associated metabolic disorders, such as T2DM and MeS, are a growing public health problem worldwide. Our goal was the identification of protein patterns that are uniquely characteristic of higher BMI, MeS, and T2DM in a Brazilian population.

EXPERIMENTAL DESIGN

Saliva and plasma proteomes, clinical parameters were analyzed in a population from the state of Rio de Janeiro, Brazil, a mixed-race population. Volunteers were sorted by their BMI into normal (n = 29), overweight (n = 25), and obese (n = 15) and were compared with individuals with MeS (n = 23) and T2DM (n = 11).

RESULTS

The Random Forest (RF) predictive model revealed that three clinical variables, BMI, HOMA-IR, and fasting blood glucose, are most important for predicting MeS and T2DM. A total of six plasmatic proteins (ABCD4, LDB1, PDZ, podoplanin, lipirin-alpha-3, and WRS) and six salivary proteins (hemoglobin subunit beta, POTEE, T cell receptor alpha variable 9-2, lactotransferrin, cystatin-S, carbonic anhydrase 6), are enhanced in T2DM and in MeS.

CONCLUSIONS AND CLINICAL RELEVANCE

Our data revealed similar alterations in protein composition across individuals with abnormal weight gain, T2DM, and MeS. This finding confirms the close link between these conditions at the molecular level in the studied population, potentially enhancing our understanding of these diseases and paving the way for the development of novel diagnostic tools.

Exploring the Relationship Between Stress, Salivary C-Reactive Protein, and Embodied Physiological Responses in a Nigerian Population

OBJECTIVES

The impacts of stress on inflammation, although hypothesized, have not been thoroughly examined, especially in relation to social and environmental factors and particularly within Black populations. This study aims to explore the biological mechanisms of embodiment linking stress and health to understand physiological changes in the body's response to psychological stress in a Nigerian population. Through a multidisciplinary approach, this study queries the relationship between stress, cortisol, and salivary C-reactive protein (sCRP), a biomarker of inflammation, while also validating the use of sCRP as a potential and accurate stress indicator in the field.

METHODS

In this cross-sectional study, 138 passive drool saliva samples (n female = 89 n male = 49) were collected and assessed for sCRP and cortisol levels in adults. Participants also completed a short demographic survey and, to measure psychological stress, the General Health Questionnaire 12 (GHQ-12). Relationships between sCRP and stress-related variables (i.e., cortisol, GHQ-12, and demographic data) were assessed using Spearman's correlations, simple regression, multivariable linear regression, and exploratory factor analysis.

RESULTS

sCRP levels ranged from 20.57 to 6879.41 pg/mL across all samples, with significant differences between female and male participants. The GHQ-12 was not a significant predictor of sCRP variability. However, socio-demographic factors such as body mass index (BMI), age, self-reported sex, ethnic identity, and cortisol were significant predictors, collectively explaining 24%-27% of the variation in sCRP.

CONCLUSION

Socio-demographic predictors like BMI, age, sex, and particularly ethnic group experience in Nigeria encapsulate aspects of embodied stress, that significantly affect sCRP variability.

Evaluation of the Relationship Between Salivary Adipokine Levels With Appetite and Anthropometric Indices in Patients With Type 2 Diabetes

OBJECTIVE

This study aimed to evaluate the association between salivary adipokine levels, including leptin, chemerin, resistin and interleukin-6, with body mass index (BMI), waist and wrist circumference and appetite in patients with type 2 diabetes.

METHODS

In this cross-sectional study, 104 participants were divided into three groups: 35 diabetic patients, 35 pre-diabetic individuals and 34 healthy controls. Unstimulated saliva samples were collected using the spitting method, and salivary levels of leptin, chemerin, resistin and interleukin-6 were measured via ELISA. Appetite was assessed using a standard questionnaire, and BMI, waist and wrist circumferences were measured with a tape measure. Statistical analysis was performed using SPSS 26, with a significance threshold set at 0.01.

RESULTS

Significant differences were found in the salivary levels of leptin, chemerin, and resistin among the three groups (p < 0.01), but no significant difference was observed in the salivary levels of interleukin-6 (p > 0.01). Analysis also revealed significant differences in appetite traits among the groups, with the highest appetite trait observed in pre-diabetic subjects (p = 0.0002). The salivary level of chemerin was significantly associated with appetite traits regardless of diabetic status (p = 0.009). Appetite was also significantly related to BMI (p = 0.002) and waist circumference (p = 0.001) in all subjects. However, no significant relationship was observed between appetite and fasting plasma glucose or HbA1c levels (p > 0.01).

CONCLUSION

The results of this study indicate that salivary levels of certain adipokines, such as leptin, chemerin and resistin, may be significantly higher in diabetic patients, although this is not true for all adipokines. While pre-diabetic patients exhibited a higher level of appetite, no positive correlation was found between salivary adipokine levels (except chemerin) and appetite or anthropometric characteristics, irrespective of diabetic status.

The response of salivary proinflammatory biomarkers to tooth extraction in individuals with type II diabetes mellitus

PURPOSE

This study investigated the levels of salivary proinflammatory cytokines in the saliva of patients living with type II diabetes mellitus (DM) compared to those in healthy individuals three times: before tooth extraction and at 2 hours and 2 days after tooth extraction.

METHODS

The study included 27 participants. Among them, 20 (n = 20; 74%) had type II DM, and seven (n = 7; 26%) were healthy control subjects. Saliva samples were collected at three time intervals: before tooth extraction and 2 hours and 2 days after tooth extraction. The salivary biomarkers were investigated using a Luminex multiplex assay. These salivary biomarkers included tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), interleukin 1-beta (IL-1β), and interferon-gamma (IFN-γ).

RESULTS

At baseline, patients with type II DM had significantly lower levels of IL-1β (P = 0.016). Moreover, 2 hours after extraction, patients with type II DM had significantly lower levels of IL-1β and TNF-α than did healthy control subjects (P = 0.046 and P = 0.020, respectively). In addition, 2 days after tooth extraction, the DM group had significantly greater IL-6 levels (P = 0.010) than the control group.

CONCLUSIONS

In patients with type II DM, salivary proinflammatory biomarker levels are generally comparable or lower than those in healthy control subjects. Proinflammatory cytokines manifest differently in patients with type II DM after tooth extraction than in normal healthy individuals. There is generally a delayed early response of salivary proinflammatory markers in patients living with type II DM who undergo tooth extraction.

Salivary Proteome and Intact N-Glycopeptides Analysis Reveal Specific Signatures in Periodontitis

Periodontitis is a prevalent oral inflammatory disease that can result in tooth loss and is closely linked to type 2 diabetes (T2D). In this study, we analyzed the salivary proteome and intact N-glycopeptides (IGPs) of individuals with mild-moderate, severe, aggressive periodontitis, and periodontitis with T2D, including those treated with antidiabetic drugs, to identify specific signatures associated with the disease. Our results revealed that salivary proteins and glycoproteins were altered in all periodontitis groups (PRIDE ID: 1-20230612-72345), with fucose- and sialic acid-containing N-glycans showing the greatest increase. Additionally, differentially expressed proteins were classified into 9 clusters, including those that were increased in all periodontitis groups and those that were only altered in certain types of periodontitis. Interestingly, treatment with antidiabetic drugs reversed many of the changes observed in the salivary proteome and IGPs in T2D-related periodontitis, suggesting a potential therapeutic approach for managing periodontitis in patients with T2D. Consistent with MS/MS results, the expression of salivary IGHA2 and Fucα1-3/6GlcNAc (AAL) was significantly increased in MP. These findings provide new insights into the pathogenesis of periodontitis and highlight the potential of salivary biomarkers for diagnosis, prognosis, and monitoring of disease progression and treatment response.

The Post-Translational Modifications of Human Salivary Peptides and Proteins Evidenced by Top-Down Platforms

In this review, we extensively describe the main post-translational modifications that give rise to the multiple proteoforms characterized to date in the human salivary proteome and their potential role. Most of the data reported were obtained by our group in over twenty-five years of research carried out on human saliva mainly by applying a top-down strategy. In the beginning, we describe the products generated by proteolytic cleavages, which can occur before and after secretion. In this section, the most relevant families of salivary proteins are also described. Next, we report the current information concerning the human salivary phospho-proteome and the limited news available on sulfo-proteomes. Three sections are dedicated to the description of glycation and enzymatic glycosylation. Citrullination and N- and C-terminal post-translational modifications (PTMs) and miscellaneous other modifications are described in the last two sections. Results highlighting the variation in the level of some proteoforms in local or systemic pathologies are also reviewed throughout the sections of the manuscript to underline the impact and relevance of this information for the development of new diagnostic biomarkers useful in clinical practice.

Effects of Shenlian formula on microbiota and inflammatory cytokines in adults with type 2 diabetes: a double-blind randomized clinical trial

OBJECTIVES

To observe the efficacy of Shenlian formula (SL formula, ), which consist of Huanglian () and Renshen (), in the treatment of type 2 diabetes mellitus (T2DM) and explore the effects on gut microbiota and serum inflammatory cytokines.

METHODS

In a double-blind, randomized, placebo-controlled parallel-group clinical trial, 31 adults with T2DM were randomly allocated to receive the SL formula or placebo for 12 weeks. Body mass index (BMI), blood lipid indices, glycemic biomarkers including glycated hemoglobin (HbA1C), fasting plasma glucose (FPG), postprandial blood glucose (PBG), fasting insulin levels (FIL), fasting C-peptide (C-P), homoeostasis model assessment for insulin resistance (HOMA-IR) and inflammatory cytokines were assessed at baseline and 12 weeks. The contents of gut microbiota were determined by pyrosequencing of the V3-V4 regions of 16S rRNA genes.

RESULTS

Sixteen cases were allocated in the treatment group and 15 in the placebo group. Compared with the placebo, SL formula resulted in a higher significant reduction in PBG [(?1.318 ± 0.772)(?0.008 ± 1.404) mmol/L, 0.003], BMI [(?0.611 ± 0.524)(0.957 ± 2.212) kg/m, 0.01], FIL [(?1.627 ± 6.268)(3.976 ± 6.85) μIU/mL, 0.02], HOMA-IR [(?0.530 ± 1.461)(1.511 ± 2.288), 0.006], and C-reactive protein (CRP) [(?1.307 ± 0.684)(0.828 ± 0.557) mg/L, 0.04]. In terms of gut microbiota, compared with the placebo, the SL formula resulted in a significant decrease in species richness and evenness.

CONCLUSIONS

The SL formula showed the efficacy to improve postprandial blood glucose, insulin resistance, BMI and CRP levels. In addition, it could reduce the total number, richness and evenness of species, meanwhile increase the abundance of probiotics to modulate the structure of gut microbiota in patients with T2DM. However, further studies are required for exploring the deeper mechanism of TCM on gut microbiota.

Role of Chlorhexidine and Herbal Oral Rinses in Managing Periodontitis

OBJECTIVE

The aim of this research was to assess the effect of 0.12% chlorhexidine (CHX) and a Salvadora persica-based mouthwash on whole salivary tumour necrosis factor-alpha (TNF-α) levels and periodontal inflammation in patients with type 2 diabetes mellitus (T2DM).

METHODS

Patients with and without medically diagnosed T2DM were included. Patients' medical records were evaluated to confirm the diagnosis of T2DM. All patients underwent nonsurgical periodontal therapy (NSPT). Patients were divided into 2 subgroups. In the test and control group, patients were advised to rinse with an S persica-based mouthwash and a non-alcoholic 0.12% CHX after NSPT twice daily for 2 weeks, respectively. Demographic data were collected. Full-mouth plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment loss (AL) were measured, and whole salivary TNF-α levels were gauged at baseline and at 3-month follow-up. Haemoglobin A1c (HbA1c) levels were measured in all patients at baseline and at 3-month follow-up. Sample size estimation was done, and group comparison was performed. Level of significance was set at P < .01.

RESULTS

Twenty-one nondiabetic individuals and 21 patients with T2DM were included. At baseline, there was no significant difference in clinical and radiographic periodontal parameters amongst in patients with and without T2DM. At 3-month follow-up, HbA1c, TNF-α, PI, PD, and clinical AL were comparable with their respective baseline values in the test and control groups amongst patients with T2DM. In nondiabetic individuals, there was a significant reduction in PI (P < .01), GI (P < .01), and PD (P < .01), and TNF-α (P < .01) at 3-month follow-up in the test and control groups compared with their respective baseline scores.

CONCLUSIONS

In the short term, NSPT with 0.12% CHX or S persica-based mouthwashes is more effective in reducing periodontal inflammation and whole salivary TNF-α levels in nondiabetic individuals than in patients with T2DM with periodontal inflammation.

The Role of Salivary C-Reactive Protein in Systemic and Oral Disorders: A Systematic Review

Background: Blood sampling is expensive, time-consuming, invasive, and requires technical facilities, which can be replaced by more convenient samples such as saliva. C-reactive protein (CRP) is a widely used biomarker in the management of many disorders and plasma CRP (pCRP) is suggested to be replaced by salivary CRP (sCRP). This study aimed to systematically review all available literature on the sCRP levels in systemic and oral disorders and how sCRP and pCRP levels correlate among these patients and healthy individuals. Methods: In this systematic review, a PubMed, Embase, Scopus, and Google Scholar search was conducted on October-2021 to identify all research investigating sCRP levels in systemic and oral disorders. Results: A total of 130 publications were analyzed in the review. Most of the studies reported that sCRP and pCRP levels are correlated, and sCRP is a reliable alternative for pCRP level for the diagnosis and management of medical conditions. sCRP has been measured in many different medical and oral disorders and significantly correlated with disease activity in most cases. Conclusion: Salivary CRP is a good alternative for Plasma CRP levels in most cases.

Changes in salivary biomarkers associated with periodontitis and diabetic neuropathy in individuals with type 1 diabetes

The objective of this pilot clinical study was to identify salivary biomarkers that are associated with periodontal disease and measures of diabetic autonomic dysfunction. Saliva samples from 32 participants were obtained from 3 groups: healthy (H), type 1 diabetes mellitus (DM), and type 1 diabetes mellitus with neuropathy (DMN). Based on the periodontal examination, individuals’ mean Periodontal Screening and Recording scores were categorized into two groups (periodontally healthy and gingivitis), and correlated to specific salivary inflammatory biomarkers assessed by a customized protein array and enzyme assay. The mean salivary IgA level in DM was 9211.5 ± 4776.4 pg/ml, which was significantly lower than H (17,182.2 ± 8899.3 pg/ml). IgA in DMN with healthy periodontium was significantly lower (5905.5 ± 3124.8 pg/ml) compared to H, although IgA levels in DMN patients with gingivitis (16,894. 6 ± 7084.3) were not. According to the result of a logistic regression model, IgA and periodontal condition were the indicators of the binary response given by H versus DM, and H versus DMN, respectively. These data suggest that selected salivary biomarkers, such as IgA, combined with a periodontal examination prior to obtaining salivary samples can offer a non-invasive method to assess risk for developing diabetic neuropathy.

Evaluation of TNF-α and IL-6 in saliva among diabetic retinopathy patients in East Coast Malaysia

OBJECTIVE

To compare tumor necrosis factor-alpha (TNF) and interleukin (IL)-6 levels in saliva between different stages of diabetic retinopathy (DR).

METHODS

This comparative cross-sectional study was conducted between January 2018 and November 2020. This study included diabetes mellitus (DM) patients with no DR, non-proliferative DR (NPDR), and proliferative DR (PDR). None of the patients with DM were included in the control group. Unstimulated saliva samples were then collected. TNF-α and IL-6 levels were measured.

RESULTS

Altogether, 120 patients were included in the study (DM without DR, 33 patients; DM with NPDR, 30 patients; DM with PDR, 32 patients; non-DM, 25 patients). The mean IL-6 level in saliva was significantly higher in the DM group (0.033±0.005 pg/ml) than in the non-DM group (0.027±0.001 pg/ml) (p<0.001 after adjusting for covariates). There was no significant difference in mean salivary TNF-α between patients with DM and those without DM after adjusting for covariates. The mean IL-6 in saliva was significantly higher in the NPDR (0.036±0.003 pg/ml) and PDR (0.093±0.023 pg/ml) groups than in the no DR group (0.027±0.001 pg/ml) (p<0.001 and p<0.001, respectively). Mean TNF-α in saliva was significantly higher in the NPDR (0.086±0.022 pg/ml) and PDR (0.093±0.023 pg/ml) groups than in the no DR group (0.049±0.011 pg/ml) (p=0.015 and p=0.003, respectively).

CONCLUSION

There is an association between inflammatory biomarkers in saliva (IL-6 and TNF-α) and severity of DR among patients with DM, suggesting that these salivary biomarkers are potential biomarkers for screening, monitoring, and predicting the progression of DR.

Salivary IL-6 Concentration Is Associated with Frailty Syndrome in Older Individuals

Background: One of the physiological changes that is most closely associated with frailty is the increase in pro-inflammatory cytokines, and IL-6 in particular. Most studies have demonstrated this association using blood samples. We analyzed the relationship between frailty syndrome, individual frailty criteria, and IL-6 levels obtained by saliva tests. Methods: A cross-sectional pilot study was performed among women institutionalized in nursing homes. Frailty was defined as having three or more of the following components: low lean mass, weakness, self-reported exhaustion, low activity level, and slow walking speed; prefrailty was defined as having one or two of those components. Results: There was a significant and positive correlation between the frailty score and salivary IL-6 concentration. Regarding the associations between IL-6 and individual dichotomized frailty criteria, there were significant differences in salivary IL-6 concentration in two frailty criteria: weight loss (p = 0.002) and low physical activity (p = 0.007). Receiver operating characteristic curve analysis showed that IL-6 concentration significantly (p < 0.05) (although moderately) discriminated patients that progressed in the frailty syndrome (the area under the curve value was 0.697 with 95% CI 0.566–0.827). Conclusions: Salivary IL-6 concentration can be used as potential biomarker of frailty syndrome and as a tool to monitor the effects of interventions in frail individuals.

Correlations between Salivary Immuno-Biochemical Markers and HbA1c in Type 2 Diabetes Subjects before and after Dental Extraction

Dental extraction can trigger certain sequences of complex processes that involve both hard (alveolar bone) and soft tissue (periodontal ligament, gingiva) remodeling. Type 2 diabetes is a serious risk factor for many oral pathologies, both in terms of progression and severity, but also regarding subsequent rehabilitation possibilities. The aim of this study was to establish whether certain molecules: osteoprotegerin (OPG), kappa B nuclear factor receptor activator ligand (RANKL), hepatocyte growth factor (HGF), tumor necrosis factor-α (TNF-α), interleukin 18 (IL-18), matrix metalloproteinase 9 (MMP-9) and oxidative stress markers-total oxidant status (TOS), total antioxidant capacity (TAC)-evaluated in saliva are modified post-extraction in type 2 diabetes mellitus subjects and whether there is a correlation with HbA1c levels. The aforementioned markers plus HbA1c were investigated in a group of systemically healthy subjects (n = 45) and in a type 2 diabetes mellitus group (n = 41) before and three months after a tooth extraction. Diabetes patients' recorded increased levels of OPG, RANKL, TNF-α, MMP-9, IL-18 and TOS compared to controls both pre- and post-extraction. In both study groups, the average OPG, HGF and TAC level recorded an upward trend three months post-extraction. TNF-α registered a statistically significant decrease only in the diabetes group after dental extraction, together with a decrement of mean HbA1c levels in the diabetes group. By plotting the ROC (receiver operating characteristic) curve, at baseline RANKL, TNF-α, IL-18, MMP-9, TOS and OPG were good predictors of HbA1c levels. Post-extraction, there was a significant correlation between HbA1c and oxidative status biomarkers, however the linear regression model indicated the influence of all studied salivary markers in HbA1c determinism, in a considerable proportion. In conclusion, our study demonstrated that several oxidative status markers and proinflammatory biomarkers are modified in the saliva of diabetic patients and they correlate to HbA1c levels, thus being potential indicators of the post-extraction healing status in the oral cavity.

Effects of Non-Surgical Periodontal Treatment on Reactive Oxygen Metabolites and Glycemic Control in Diabetic Patients with Chronic Periodontitis

BACKGROUND

Periodontal infection may contribute to poor glycemic control and systemic inflammation in diabetic patients. The aim of the present study is to evaluate the efficacy of non-surgical periodontal treatment in diabetic patients by measuring oxidative stress outcomes.

METHODS

Sixty diabetic patients with periodontitis were enrolled, treated with scaling and full-mouth disinfection, and randomly prescribed chlorhexidine mouthwash, antioxidant mouthwash, or ozone therapy. Reactive oxygen metabolites (ROMs), periodontal parameters, and glycated hemoglobin were measured at baseline and then at 1, 3, and 6 months after.

RESULTS

At baseline, all patients presented with pathologic levels of plasmatic ROM (388 ± 21.36 U CARR), higher than the normal population. Probing depth, plaque index, and bleeding on probing values showed significant clinical improvements after treatment, accompanied by significant reductions of plasma ROM levels (p < 0.05). At the 6-month evaluation, the mean ROM relapsed to 332 ± 31.76 U CARR. Glycated hemoglobin decreased significantly (∆ = -0.52 units) after treatment. Both the test groups showed longer-lasting improvements of periodontal parameters.

CONCLUSION

In diabetic patients, periodontal treatment was effective at reducing plasma ROM, which is an indicator of systemic oxidative stress and inflammation. The treatment of periodontal infection might facilitate glycemic control and decrease systemic inflammation.