Application of Salivary Alpha-1 Antitrypsin in the Diagnosis of Rheumatoid Arthritis: A Pilot Study

Background and Objective: Rheumatoid arthritis (RA) is an autoimmune disease in which joints are gradually destroyed. Early diagnosis and treatment before joint deformation or destruction is important. The detection of novel RA biomarkers in saliva may facilitate early detection of RA before disease onset. This study aimed to evaluate salivary concentration of α1-antitrypsin (A1AT) in healthy patients and those with RA, and to assess the diagnostic value of salivary A1AT. Materials and Methods: In total, 80 participants were included: 20 healthy participants, and 60 patients with RA. Saliva and serum samples were obtained from all the patients. Levels of A1AT and cytokines, including interleukin-1 beta (IL-1β), IL-6, and IL-10 in saliva and serum, were evaluated using an enzyme-linked immunosorbent assay kit and Luminex assay. Data were analyzed using SPSS for Windows. Results: There was a higher level of A1AT in the saliva of patients with RA (median: 2388.66 ng/mL) than that in healthy controls (1579.06 ng/mL). There was a positive mild-to-moderate accuracy (area under the curve: 0.57-0.85) of A1AT in saliva to diagnose RA. The cut-off level (ng/mL) of A1AT in saliva for detecting RA was 1689.0. Conclusions: The obtained data can promote the application of the measurements of A1AT in saliva to diagnose RA.

Trends in waking salivary alpha-amylase levels following healing lucid dreams

Introduction

Salivary alpha-amylase (sAA) is considered a marker of autonomic nervous system activity in stress research, and atypical waking sAA responses have been reported for traumatized individuals. Lucid dreams, characterized by a dreamer's awareness of their dream state while remaining asleep, have shown promising preliminary evidence of their potential to enhance mental health. This study's objective was to evaluate sAA in relation to healing lucid dreams.

Methods

Participants experiencing PTSD symptoms attended a six-day workshop delivered via live video designed to teach techniques for transforming trauma through dreamwork and dream lucidity. Participants (n = 20) collected saliva samples each morning, immediately upon awakening (Time 1) and 30 min afterward (Time 2). sAA levels were determined by enzymatic assay, and the waking sAA slope was calculated as the difference of Time 2 minus Time 1. Participants completed dream reports each morning, with a dream classified as a 'healing lucid dream' when they reported attaining lucidity and remembered their intention to manifest a healing experience within the dreamscape.

Results

Of eight participants experiencing healing lucid dreams, four were able to provide usable saliva samples. Statistical tests on these four participants were not significant because of low power. However, nonsignificant positive associations were observed between experiencing more healing lucid dreams and increased waking sAA slope.

Conclusion

The results did not reveal a consistent effect of healing lucid dreams on waking sAA slope. Identifying meaningful patterns in this relationship will require larger samples and more stringent control over saliva collection procedures in future studies.

Salivary Biomarkers in Periodontitis: A Scoping Review

Periodontal disease is a prevalent and potentially impactful oral health condition, ranging from gingivitis to severe periodontitis. Early detection and precise management are crucial in modern dentistry due to its prevalence and potential systemic health implications. Traditional clinical assessments and radiographic imaging have been the primary diagnostic tools. However, recent advances in oral diagnostics have introduced the concept of non-invasive, easily accessible salivary biomarkers. This review explores the evolving landscape of salivary biomarkers associated with periodontal disease, offering a comprehensive analysis of recent studies. It delves into the key findings, clinical significance, and potential impact of these biomarkers in revolutionizing periodontal disease diagnostics and treatment monitoring. The study emphasizes their diagnostic and prognostic capabilities, including their ability to assess disease severity, correlate with clinical parameters, aid in early detection, and enhance personalized treatment planning. As the field of oral diagnostics continues to advance, understanding the role of salivary biomarkers in periodontal disease management holds the promise of improving precision and effectiveness in oral healthcare. This review underscores the potential for salivary biomarkers to become integral components of routine periodontal care, offering a minimally invasive and patient-centered approach to oral health management.

Association between Salivary Cortisol Levels, Dental Anxiety, and Dental Caries in Children: A Cross-Sectional Study

AIM

This study aimed to investigate the relationship between dental caries, dental anxiety, and salivary cortisol levels in children visiting pediatric dental clinics and their implications on pediatric oral health.

MATERIALS AND METHODS

A cross-sectional study was conducted at a dental university in the UAE. A total of 60 children, aged 4-12 years, were included. Salivary cortisol levels were measured using an Enzyme-Linked Immunosorbent Assay (ELISA) kit. Dental caries status was evaluated, and dental anxiety levels were assessed using the Modified Dental Anxiety Scale (MDAS). Statistical analyses, including Mann-Whitney U test and Pearson's correlation coefficient, were performed to determine significant differences and associations.

RESULTS

The study group showed significantly higher salivary cortisol levels compared to the control group (p < 0.0001). A strong positive correlation was found between salivary cortisol levels and dental caries status (p < 0.001). However, no significant difference in dental anxiety levels was observed between the study and control groups (p = 0.85). A strong positive correlation was found between dental anxiety levels and dental caries status (p < 0.001).

CONCLUSION

The findings indicate a significant association between salivary cortisol levels and dental caries, suggesting that higher cortisol levels are associated with active caries. Dental anxiety levels were positively correlated with dental caries. Understanding the relationship between these variables can contribute to better oral health strategies and interventions for children, emphasizing the importance of managing dental anxiety and stress in pediatric dental care.

CLINICAL SIGNIFICANCE

This study highlights the potential of salivary cortisol as a biomarker for assessing stress and its impact on oral health in children. By addressing dental anxiety and stress, dental professionals can provide child-friendly dental care, enhance preventive measures, and improve oral health outcomes in pediatric patients.

Salivary 1,5-Anhydroglucitol and its Correlation with Postprandial Hyperglycemia: Development and Validation of a Novel Assay

Background

Saliva has the potential to be used as a noninvasive sample for testing hyperglycemia in diabetes mellitus. Serum 1,5-anhydroglucitol (1,5-AG) decreases with an increase in blood sugar >180 mg/dl. We hypothesized that salivary 1,5-AG can be used to identify blood sugar higher than 180 mg/dl using a novel biochemical method.

Aim

This study aimed to develop a novel biochemical method for serum and salivary assessment of 1,5-AG and assess its correlation with postprandial blood sugar (PPBS) >180 mg/dl.

Methodology

The study comprised 45 controls (healthy individuals) and 45 cases (type 2 diabetic patients with PPBS >180 mg/dl). Blood and salivary samples were collected according to the study protocol. A new method was developed for the quantification of 1,5-AG in serum and saliva using liquid chromatography-mass spectrometry.

Results

The value of serum (mean -22.19 μg/ml and median -22.12 μg/ml) and salivary (mean -0.124 μg/ml and median -0.088 μg/ml) 1,5-AG was higher in healthy individuals compared to corresponding serum (mean -3.89 μg/ml and median -2.52 μg/ml) and salivary (mean -0.025 μg/ml and median - 0.025 μg/ml) levels in diabetics with PPBS >180 mg/dl. In diabetics, a significant negative correlation was noticed with PPBS levels and 1,5-AG levels in serum and saliva. Salivary 1,5-AG level <0.054 μg/ml had an 86.4% sensitivity and 87.2% specificity in predicting a blood sugar value >180 mg/dl.

Conclusion

The results of our study suggest that the short-term glycemic marker 1,5-AG can be detected in saliva and can be useful as an adjunct marker in monitoring of glycemic status in diabetic patients.

Polymethylation scores for prenatal maternal smoke exposure persist until age 15 and are detected in saliva in the Fragile Families and Child Wellbeing cohort

Prenatal maternal smoking is associated with low birthweight, neurological disorders, and asthma in exposed children. DNA methylation signatures can function as biomarkers of prenatal smoke exposure. However, the robustness of DNA methylation signatures across child ages, genetic ancestry groups, or tissues is not clear. Using coefficients from a meta-analysis of prenatal smoke exposure and DNA methylation in newborn cord blood, we created polymethylation scores of saliva DNA methylation from children at ages 9 and 15 in the Fragile Families and Child Wellbeing study. In the full sample at age 9 (n = 753), prenatal smoke exposure was associated with a 0.51 (95%CI: 0.35, 0.66) standard deviation higher polymethylation score. The direction and magnitude of the association was consistent in European and African genetic ancestry samples. In the full sample at age 15 (n = 747), prenatal smoke exposure was associated with a 0.48 (95%CI: 0.32, 0.63) standard deviation higher polymethylation score, and the association was attenuated among the European and Admixed-Latin genetic ancestry samples. The polymethylation score classified prenatal smoke exposure accurately (AUC age 9 = 0.77, age 15 = 0.76). Including the polymethylation score increased the AUC of base model covariates by 5 (95% CI: (2.1, 7.2)) percentage points, while including a single candidate site in the AHRR gene did not (P-value = 0.19). Polymethylation scores for prenatal smoking were portable across genetic ancestries and more accurate than an individual DNA methylation site. Polymethylation scores from saliva samples could serve as robust and practical biomarkers of prenatal smoke exposure.

Alpha-L-fucosidase levels in patients with oral submucous fibrosis and controls: A comparative study

Background

Oral submucous fibrosis (OSMF) in recent times has been recognized as a potentially malignant disorder (PMD) with an increased risk of developing oral squamous cell carcinoma with malignant transformation rates that vary from 0.6% to 36%. Alpha-L-fucosidase (AFU) is a lysosomal enzyme that is involved in maintaining the homeostasis of fucose metabolism. In benign and malignant tumors, the cells modulate their surface by increasing fucosylation leading to uncontrolled growth.

Aims and objectives

This study was designed to estimate the levels of salivary and serum AFU in patients with OSMF and healthy controls and also to evaluate the clinical utility of salivary AFU levels over serum.

Materials and Methods

Saliva and blood samples were collected from twenty participants in both the groups (OSMF and healthy controls). Serum and salivary alpha-L-fucosidase levels were measured by enzyme-linked immunosorbent assay. The data were subjected to appropriate statistical analysis.

Results

We found a significant increase in alpha-L-fucosidase level in OSMF compared with healthy subjects. Pearson's correlation showed salivary alpha-L-fucosidase level to have superior sensitivity in detecting OSMF compared with serum alpha-L-fucosidase.

Conclusion

The outcome of this study suggests that salivary alpha-L-fucosidase can be utilized as a biomarker in early detection of oral precancer and cancer.

Evaluation of stress among dental undergraduates and postgraduates using salivary cortisol as a biomarker

Background

Stress is a non-specific response of the body to any demand. Professional education has a certain level of stress inherent in it. Dental students have been reported in the literature to experience more stress than medical students.

Objective

To evaluate the stress levels of dental students: first-year undergraduates, house surgeons, and final-year postgraduates, using salivary cortisol as a stress biomarker.

Materials and Methods

Dental students above 18 years of age and without any systemic illness were included in the study. Those students with a drug history of corticosteroids, anti-depressants, and oral contraceptives were excluded from the study. Female participants experiencing pre-menstrual symptoms, pregnancy, and familial stressor issues were excluded from the study. First-year undergraduates, house surgeons, and final-year postgraduates were enrolled in the study. Unstimulated whole saliva was collected in the morning and evening between 9:00 and 10:00 am and between 3:00 and 4:00 pm. Salivary cortisol levels were assessed by chemiluminescence immuno-assay (CLIA).

Results

Paired sample t-test was used to compare the diurnal variation among morning and afternoon samples within the groups. The salivary cortisol levels were found to be significant within the groups. One-way ANOVA was used to compare the salivary cortisol levels between the groups. The salivary cortisol levels within the groups were not statistically significant.

Conclusion

Salivary cortisol is a non-invasive biomarker of stress. Postgraduates had higher salivary cortisol levels than other study groups.

Diagnostic Accuracy of Salivary Biomarkers in Detecting Early Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

BACKGROUND

Biopsy is the gold standard for oral squamous cell carcinoma (OSCC) diagnosis. Salivary biomarkers provide promising complementary alternative diagnostic adjunct for its simple non- invasive collection and technique and to screen large population.

OBJECTIVE

To summarize and compare the existing evidence on diagnostic accuracy of salivary biomarkers with their estimation method in detecting early oral squamous cell carcinoma.

METHODS

The review protocol is registered under PROSPERO(CRD42021225704). PubMed, Google Scholar, EBSCOhost were searched from 2000 to 2020 to identify the screening potential of eight salivary biomarkers: mRNA, miRNA, DUSP100, s100P, IL-8, IL-1B, TNF-a and MMP-9. True-positive, false-positive, true-negative, false-negative, sensitivity, specificity values were extracted or calculated if not present for each study. Quality of selected studies was evaluated based on QUADAS 2 tool. Meta-analysis was performed using a bivariate model parameter for the sensitivity and specificity and summary points, summary receiver operating curve (SROC), confidence region, and prediction region were calculated.

RESULTS

Eighteen studies were included for qualitative synthesis and out of that 13 for meta-analysis. Sensitivity and specificity were calculated with AUC. For mRNA it was 91% and 90% with 0.96 AUC, miRNA had 91% and 91% with 0.95 AUC for PCR. IL-1B had 46% and 60% with 0.61 AUC, S100p had 45% and 90% with 0.57 AUC for ELISA. IL-8 had 54% and 74% for ELISA and 89% and 90% for PCR with 0.79 AUC and DUSP1 had 32% and 87% for ELISA and 76% and 83% for PCR with 0.83 AUC respectively.

CONCLUSION

Early detection of OSCC was best achieved by screening for salivary mRNA and miRNA estimated by PCR. Further investigation is required into salivary RNA as novel biomarkers and these salivary biomarkers may be potentially used for non-invasive diagnosis of early OSCC.

Role of Salivary MicroRNA and Cytokines in the Diagnosis and Prognosis of Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is the most prevalent oral malignant tumor worldwide. An early diagnosis can have a major positive impact on its prognosis. Human saliva contains cytokines, DNA and RNA molecules, circulating cells, and derivatives of tissues and extracellular vesicles, among other factors that can serve as biomarkers. Hence, the analysis of saliva may provide useful information for the early diagnosis of OSCC for its prognosis. The objective of this review was to determine the potential usefulness of salivary biomarkers (cytokines and microRNA) to diagnose OSCC and improve its prognosis. A combination of salivary miRNA and proteomic data could allow a definitive and early diagnosis to be obtained. However, there remains a need to optimize and standardize the protocols used to quantify miRNAs.

Lack of Salivary Long Non-Coding RNA XIST Expression Is Associated with Increased Risk of Oral Squamous Cell Carcinoma: A Cross-Sectional Study

Studies have shown that there is a disparity between males and females in south-east Asia with regard to oral cancer morbidity. A previous study found that oral cancer tissue showed loss of heterozygosity of the X-linked lncRNA XIST gene. We suggest that XIST may play an important role in oral cancer morbidity when associated with sex. Saliva contains proteins and RNAs that are potential biomarkers for the diagnosis of diseases. This study investigated salivary XIST expression and the correlation to clinical-pathological data among oral squamous cell carcinoma patients. Salivary XIST expression was only observed in females, and a high proportion of females with OSCC lack salivary lncRNA XIST expression (88%). The expression showed no correlation with alcohol consumption, betel quid chewing, or cigarette smoking habits. People lacking salivary lncRNA XIST expression had a significantly increased odds ratio of suffering from OSCC (OR = 19.556, p < 0.001), particularly females (OR = 33.733, p < 0.001). The ROC curve showed that salivary lncRNA XIST expression has acceptable discrimination accuracy to predict the risk of OSCC (AUC = 0.73, p < 0.01). Lack of salivary lncRNA XIST expression was associated with an increased risk of OSCC. We provided an insight into the role of salivary lncRNA XIST as a biomarker to predict the morbidity of OSCC.

Systemic Investigation Identifying Salivary miR-196b as a Promising Biomarker for Early Detection of Head-Neck Cancer and Oral Precancer Lesions

Background: Liquid biopsy is a rapidly growing field, for it may provide a minimally invasive way to acquire pathological data for personalized medicine. This study developed a systemic strategy to discover an effective salivary biomarker for early detection of patients with head-neck squamous carcinoma (HNSC) and oral precancer lesion (OPC). Methods: A total of 10 miRNAs were examined in parallel with multiple independent cohorts. These included a training set of salivary samples from HNSC patients, the TCGA-HNSC and GSE31277 cohorts to differentiate miRNAs between tumor and normal tissues, and groups of salivary samples from healthy individuals, patients with HNSC and OPC. Results: The combined results from the salivary training set and the TCGA-HNSC cohort showed that four miRNAs (miR-148b, miR-155, miR-196b, and miR-31) consistently increased in HNSC patients. Further integration with the GSE31277 cohort, two miRNAs (miR-31 and miR-196b) maintained at high significances. Further assessment showed that salivary miR-196b was a prominent diagnostic biomarker, as it remarkably discriminated between healthy individuals and patients with HNSC (p < 0.0001, AUC = 0.767, OR = 5.64) or OPC (p < 0.0001, AUC = 0.979, OR = 459). Conclusion: Salivary miR-196b could be an excellent biomarker for diagnosing OPC and early detection of HNSC. This molecule may be used for early screening high-risk groups of HNSC.

Changes in Salivary Amylase and Glucose in Diabetes: A Scoping Review

BACKGROUND AND OBJECTIVE

Diabetes mellitus (DM) is a common long-term disease which can be related with salivary amylase levels. DM has recently been associated with salivary amylase diagnostics that could further impair diagnoses in the diabetic population, as well as being an interesting alternative to traditional methods of determine glucose levels. The main advantage of this method is related to the fact that it is a fast diagnostic method. The DM population experiences changes to their metabolism which affects their salivary parameters, making this an alternative procedure for diagnosis and follow-up of the illness due to the non-invasive nature of salivary analyzes. The objective of this review is to summarize the evidence regarding the changes in salivary amylase and glucose levels, and their relationship with blood markers of glycemic control used in clinical settings such as blood glucose and glycated hemoglobin. The differences in salivary amylase levels depending on the method of saliva collection under fasting or non-fasting conditions. The changes in salivary amylase depends on the type of diabetes, the type of insulin treatment or the quality of glycemic control.

CONCLUSIONS

Salivary amylase concentration is increased in diabetic patients in most of the studies and salivary glucose concentration in all studies in both fasting and non-fasting (post-prandial) conditions. Salivary amylase and glucose concentration represent potential non-invasive biomarkers to evaluate glycemic control and clinical management of diabetic patients, although it is necessary to evaluate the influence of potential modulating factors such as age, duration diseases, sex and the effects of pharmacological treatments in these outcomes which remained to be elucidated.

Salivary Biomarkers and Their Application in the Diagnosis and Monitoring of the Most Common Oral Pathologies

Saliva is a highly versatile biological fluid that is easy to gather in a non-invasive manner—and the results of its analysis complement clinical and histopathological findings in the diagnosis of multiple diseases. The objective of this review was to offer an update on the contribution of salivary biomarkers to the diagnosis and prognosis of diseases of the oral cavity, including oral lichen planus, periodontitis, Sjögren’s syndrome, oral leukoplakia, peri-implantitis, and medication-related osteonecrosis of the jaw. Salivary biomarkers such as interleukins, growth factors, enzymes, and other biomolecules have proven useful in the diagnosis and follow-up of these diseases, facilitating the early evaluation of malignization risk and the monitoring of disease progression and response to treatment. However, further studies are required to identify new biomarkers and verify their reported role in the diagnosis and/or prognosis of oral diseases.

Evaluation of Osteocalcin Levels in Saliva of Periodontitis Patients and Their Correlation with the Disease Severity: A Cross-Sectional Study

OBJECTIVES

 The present study aimed to investigate osteocalcin levels in saliva of healthy and periodontitis patients and correlate these levels with periodontitis severity.

MATERIALS AND METHODS

 This cross-sectional study was conducted in a hospital setup. A total of 95 individuals participated in the study with 46 subjects in group I (healthy individuals) and 49 subjects in group II (mild, moderate, and severe chronic periodontitis patients). A detailed assessment of clinical periodontal parameters and alveolar bone loss was made. Unstimulated saliva samples were collected from all study subjects and osteocalcin levels were quantitatively analyzed by sandwich enzyme-linked immunosorbent essay technique.

STATISTICAL ANALYSIS

 One-way analysis of variance, Spearman's correlation test, and Pearson's chi-squared test were applied at a significance level of 95%. p-Values less than 0.05 were considered statistically significant.

RESULTS

 The results showed a significant association of qualification with group II (p < 0.02). Bone loss scores were also significantly associated with periodontitis severity (p < 0.01). However, no statistically significant difference was observed between group I and group II in terms of mean salivary osteocalcin levels (p = 0.68). Also, an insignificant correlation was also observed between osteocalcin levels and periodontitis severity (p = 0.13).

CONCLUSION

 The overall study results showed that there was no significant difference between saliva osteocalcin levels of healthy and periodontitis patients. Also, there was a nonsignificant correlation between osteocalcin levels and periodontitis severity. The findings of the present study support the hypothesis that low osteocalcin levels in saliva might be considered as a poor indicator of periodontal disease progression and severity.

Assessment of lactate dehydrogenase enzyme levels in saliva and serum of oral submucous fibrosis and leukoplakia patients

Background:

Pathology involving the oral epithelium may alter the level of salivary concentration of LDH. Thus its estimation can be used as a non invasive screening tool for the early detection of OPMDs and also to predict its malignant transformation especially in high risk population.

Aims and Objectives:

To evaluate the salivary and serum levels of lactate dehydrogenase (LDH) in patients having of oral submucous fibrosis (OSMF) and leukoplakia and compare it with healthy individuals.

Materials and Methods:

A total of 120 subjects were selected and divided into three groups comprising clinically diagnosed cases of OSMF and leukoplakia and healthy subjects as controls. Unstimulated whole saliva and blood samples were collected under aseptic conditions for biochemical estimation of LDH by Semiautomatic Analyzer using LDH kit utilizing enzymatic UV-Kinetic method. The values obtained were statistically analyzed using the SPSS software version 20.0. P-value < 0.05 was considered significant.

Results:

The mean salivary LDH level in Group I (OSMF) was 631.67 + 7.67, Group II (Leukoplakia) was 492.28 + 16.17 and Group III (Healthy Control) was 140.62 + 8.87. There was a statistically significant difference between the Serum and salivary LDH levels among the various groups of study population. A positive correlation between salivary LDH and serum LDH level was seen and the regression equation for OSMF and leukoplakia was computed.

Conclusion:

A significant difference was found between mean salivary LDH Levels and serum LDH levels in patients with leukoplakia, OSMF and health controls. A positive correlation was also established between salivary and serum LDH levels in patients with OSMF and leukoplakia patients making saliva a potent non invasive tool for early prediction and detection of PMOD and its malignant transformation.

Comparative evaluation of salivary malondialdehyde levels as a marker of lipid peroxidation in early childhood caries

Objective

The aim of this study was to evaluate the association between lipid peroxidation and dental caries in children with ECC by estimating the levels of MDA in saliva of children.

Materials and Methods

A total of 150 children were selected; 75 children with ECC and 75 children without caries (non-ECC). Saliva samples were collected and centrifuged at 12,000 rpm for 24 min at 4°C to obtain a supernatant. MDA levels were estimated by Buege and Aust method by using thiobarbituric acid. The data obtained were analyzed by Student's t-test to compare MDA levels between the groups.

Results

MDA levels were higher in children with ECC. There was no statistically significant difference between children with ECC and without ECC (non-ECC).

Conclusion

MDA levels were slightly higher in children with ECC, indicating the role of lipid peroxidation in the carious process.

iTRAQ-based proteomics reveals SOD2 as a potential salivary biomarker in liver cancer

BACKGROUND

Salivary proteomic analysis has been extensively used in a wide range of cancer, but not in hepatocellular carcinoma. The aim of this study was to identify potential salivary biomarkers for hepatocellular carcinoma clinical screening.

METHODS

In this study, we performed isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomics analysis to detect differentially expressed proteins between saliva samples from 15 hepatocellular carcinoma patients and 15 healthy controls. Enzyme-linked immunosorbent assay (ELISA) verification was undertaken in saliva samples from 14 hepatocellular carcinoma patients and 14 healthy controls.

RESULTS

Overall, 133 proteins with significant differential expression level (ratio > 1.5 or < 0.67) were detected. Using bioinformatic analysis, two candidate proteins were selected and subsequently verified by ELISA. The increased expression of superoxide dismutase 2, mitochondrial (SOD2) in hepatocellular carcinoma patients was confirmed by ELISA, with an area under the curve value of 0.9082.

CONCLUSIONS

iTRAQ-based quantitative proteomics revealed that SOD2 might serve as a potential salivary biomarker for hepatocellular carcinoma detection. Our results indicated that a noninvasive and inexpensive salivary test might be established for hepatocellular carcinoma detection.

Relationship between Salivary Alpha-2 Macroglobulin and HbA1c among Patients with Type-2 Diabetes Mellitus: A Cross-sectional Study

CONTEXT

Type-2 diabetes mellitus (DM2) requires an adequate glycemic control to avoid diabetic complications. The best parameter available is glycosylated hemoglobin (HbA1c), as it gives us an overview of an individuals' glycemic control of the previous 4 months. Salivary biomarkers used as a diagnostic tool can indicate the control or degree of progression of diseases. Studies indicate that salivary alpha-2-macroglobulin (A2MG) levels are elevated in diabetes patients.

AIMS

To study the relationship of salivary A2MG with glycosylated Hba1c among patients with DM2.

SETTINGS AND DESIGN

A total of 87 patients of DM2, age 35-65 years were recruited.

MATERIALS AND METHODS

The routine oral cavity examination and dental check-up was done to rule out any dental disease. The patients with hepatic diseases and inflammatory diseases of oral cavity and body were excluded. The values of HbA1c were collected from the records of patients. Salivary A2MG levels were estimated by enzyme-linked immunosorbent assay. Levels of fasting and postprandial blood sugar, serum creatinine, and A2MG were compared with the HbA1c groups (<7 and ≥ 7).

STATISTICAL ANALYSIS USED

Descriptive statistics (Software SPSS version 20.0). Nonparametric Pearson correlation test was used to assess the correlation between HbA1c and A2MG.

RESULTS

A positive correlation between salivary levels of A2MG and blood levels of HbA1c in blood was observed in this study. Results showed that there was also a significant correlation in mean values of fasting and postprandial blood sugar, serum creatinine, and salivary A2MG in diabetic subjects.

CONCLUSION

Measurement of A2MG in saliva represents a promising noninvasive alternative method to evaluate glycemic index and consequently avoiding comorbidities.

A Cross-Sectional Study of Endogenous Antioxidants and Patterns of Dental Visits of Periodontitis Patients

Periodontitis is an inflammatory disease, wherein endogenous antioxidants help to balance the inflammatory status. Oral health behaviors are related to the periodontal disease status. The aim of this study was to explore the associations between oral health behaviors and endogenous antioxidants in periodontitis patients. In total, 225 subjects diagnosed with periodontitis were enrolled in the study. Information obtained from the initial interview included socioeconomic and demographic characteristics, lifestyle factors, and oral health-related behaviors. The clinical periodontal parameters evaluated included bleeding on probing (BOP), the plaque index (PI), and probing depth (PD). Stimulated saliva was collected before periodontal therapy to determine five endogenous antioxidants (copper-zinc superoxide dismutase (Cu/Zn SOD), manganese SOD (MnSOD), thioredoxin 1 (Trx1), peroxiredoxin 2 (Prx2), and catalase (CAT)). When these five factors were adjusted for in patients whose last previous dental visit was >1 year, the patients' PI, BOP, and PD showed significant decreases because of an elevation in the Cu/Zn SOD level. Associations of endogenous antioxidants with levels of clinical periodontal parameters were much higher in subjects whose last previous dental visit was >1 year, compared to subjects whose last previous dental visit was <1 year. This study provides a better understanding of dental visit patterns and the salivary endogenous antioxidants that may underlie the symptomatic development of preclinical periodontitis.

Effect of Initial Periodontal Therapy on Salivary Trefoil Factor (TFF3) in otherwise Healthy Patients with Gingivitis and Chronic Periodontitis

Background:

The search for an ideal biomarker which can determine the current disease status that predicts the sites and individuals with increased susceptibility to periodontal disease has been going on since a long time. One such group of molecules which have been investigated recently are the trefoil factors, and the present study aims to determine the role of salivary trefoil factor 3 (TFF3) in periodontitis and gingivitis patients.

Materials and Methods:

A total of fifty participants, of which 25 were diagnosed with moderate-to-severe periodontitis and 25 with chronic gingivitis were included in the study. The routine periodontal parameters were recorded at baseline and at 6 weeks which included plaque index, gingival index, bleeding index, probing depth, and clinical attachment level. The saliva samples were collected from both the groups at baseline and 6 weeks after nonsurgical periodontal therapy and analyzed by enzyme-linked immunosorbent assay to estimate the concentration of trefoil factor 3.

Results:

All the periodontal parameters improved at 6-week reevaluation in both the groups. There was a significant change in the TFF3 levels in the periodontitis group from baseline to 6 weeks, and the concentrations were found to be higher following nonsurgical therapy, whereas the quantum of change in the gingivitis group was negligible. The levels of TFF3 remained unchanged in those periodontitis participants who required surgical intervention at the 6^th-week reevaluation.

Conclusion:

The estimation of TFF3 levels may aid in decision-making in the treatment strategy of patients with moderate-to-severe periodontitis.

Fibroblast Growth Factor-2: A Promising Biomarker for Anxiety and Trauma Disorders

Anxiety and trauma disorders are a significant source of global burden. Although it is clear that there is great heterogeneity in humans' response to trauma and stress, most research on fear and anxiety has focused on the "average" animal. Increased understanding of the sources of individual differences in fear reactions may lead to more refined means of predicting who is at risk for the development of anxiety disorders so that early preventative interventions can be implemented. This commentary highlights recent cross-species work (in rats and humans) indicating that the neurotrophin fibroblast growth factor-2 (FGF2) holds promise as a potential biomarker for anxiety disorder vulnerability. Both central (hippocampal) and peripheral (serum and saliva) markers of FGF2 correlate negatively with fear expression after an aversive conditioning experience. Here, 2 broad accounts of the potential mechanism of vulnerability captured by measures of FGF2 are outlined. In particular, it is suggested that basal differences in FGF2 (across different tissue types) may provide a general index of one's regenerative capacity; alternatively, differences in FGF2 reactivity (in specific tissue types) may be indicative of one's coping capacity in response to stress.

Evaluation of saliva and plasma cytokine biomarkers in patients with oral squamous cell carcinoma

The aim of this study was to investigate potential biomarkers in human saliva and plasma to aid in the early diagnosis of oral squamous cell carcinoma (OSCC). Saliva and plasma samples obtained from OSCC patients (n=41) and non-oral cancer patients (n=24) were analyzed by Luminex Bead-based Multiplex Assay. Data were analyzed using the non-parametric Mann-Whitney U-test, Kruskal-Wallis test, and receiver operating characteristics curve (ROC) to evaluate the predictive power of 14 biomarkers individually for OSCC diagnosis. The plasma level of IP-10 in early OSCC differed significantly from that in controls. Among the salivary biomarkers, IL-1β, IL-6, IL-8, MIP-1β, eotaxin and IFN-γ and TNF-α showed significant differences between OSCC patients and controls. With respect to carcinogenesis, significant differences in plasma levels of eotaxin, G-CSF, and IL-6 were found between OSCC stages III/IV and OSCC stages I/II. The area under the curve (AUC) for OSCC vs. control was greater than 0.7 for plasma IP-10 and saliva IL-1β, IL-6, IL-8, and TNF-α. The study findings indicate that salivary biomarkers may serve a useful role as a complementary adjunct for the early detection of oral OSCC. With regard to the evaluation of tumour progression, plasma eotaxin, G-CSF, and IL-6 may help in the detection of advanced OSCC. However, the correlation between saliva and plasma biomarkers in OSCC was weak.

Serum and salivary macrophage migration inhibitory factor in patients with oral squamous cell carcinoma

The overexpression of macrophage migration inhibitory factor (MIF) has been identified in a variety of tumors and the investigation of its molecular mechanisms in tumor progression is a key topic of research. The present study aimed to investigate MIF as a potential marker for disease control or recurrence, and to assess the association between serum and salivary MIF and the clinicopathological characteristics of patients with oral squamous cell carcinoma (OSCC). Serum and salivary samples were collected prior to and following the surgical treatment of 50 patients with OSCC. MIF concentrations were assessed by enzyme-linked immunosorbent assay and the adopted level of statistical significance was P<0.05. The results revealed that serum MIF concentrations were significantly reduced following tumor resection in OSCC patients. Furthermore, higher preoperative salivary MIF concentrations were observed in patients with larger tumors and in those who succumbed to the disease. In conclusion, high salivary and serological MIF concentrations were identified in patients with OSCC. Nevertheless, only serological MIF concentrations may be considered as a potential marker for the early detection of OSCC recurrence once the salivary levels, prior and following treatment, do not show any significant differences.

Alpha amylase as a salivary biomarker of acute stress of venepuncture from periodic medical examinations

Periodic occupational health examinations often require venepuncture. Acute psychological and physical stressors during such procedure result in sympathetic stimulation and increased salivary protein secretion, including salivary α-amylase (SAA). We studied SAA response to venepuncture during such examination. Fifty-eight healthy males undergoing periodic medical examination reported perceived stress level (PSL) scores (on a five-point scale) and provided passive drool saliva samples at 15-min (T1) and 1-min before (T2); and 1-min (T3) and 15-min after venepuncture (T4). A subset of 33 participants available for repeat examination on a control day when there was no venepuncture provided saliva samples at the corresponding times for comparison. Saliva SAA activity levels were analyzed using a SAA assay kit (Salimetrics LLC, USA). Among 58 participants, mean SAA increased from T1 (89.95 U/L) to T2 (109.5 U/L) and T3 (116.9 U/L). SAA remained elevated 15 min after venepuncture (121.0 U/L). A positive trend in the difference of SAA between T3 and T1 was noted among subjects with increasing mean PSL scores. T3–T1 values were 0.6 (among those with PSL ≤ 1, n = 24), 11.3 (among those with PSL between 1 and 1.5, n = 18), and 78.9 (among those with PSL > 1.5, n = 16). SAA increment over four-time points was significantly higher on the venepuncture compared to the control day (P = 0.021). SAA increases in response to the acute stress of venepuncture during a periodic medical examination, and remains elevated 15 min after the procedure. In comparison, such fluctuations in SAA were not seen on a control day. During venepuncture, increase in SAA from baseline is higher among those who reported greater self-perceived stress during the procedure.

Salivary biomarkers for detection of oral squamous cell carcinoma - current state and recent advances

Oral squamous cell carcinoma (OSCC) is the most common malignant neoplasm of the oral cavity. Detection of OSCC is currently based on thorough clinical oral examination combined with biopsy for histological analysis. Most cases of OSCC are not detected until the cancer has developed into advanced stages; thus, a reliable early stage diagnostic marker is needed. This literature review presents an overview of the status of current advances in salivary diagnostics for OSCC. Though many protein and mRNA salivary biomarkers have been identified that can detect OSCC with high sensitivity and specificity, the most discernable findings occur with the use of multiple markers. Studies that incorporate proteomic, transcriptomic, and potentially additional "omics", including methylomics, need to be initiated to bring technology to clinical applications and allow the best use of saliva in diagnosing OSCC.

Human IgG antibody response to Aedes aegypti Nterm-34 kDa salivary peptide as an indicator to identify areas at high risk for dengue transmission: a retrospective study in urban settings of Vientiane city, Lao PDR

OBJECTIVE

Using human IgG antibody response to the Aedes Nterm-34 kDa salivary peptide as an indicator of human exposure to Aedes bites in surveying exposed populations from areas at risk of dengue virus (DENV) transmission in urban settings of Vientiane city, Lao PDR.

METHODS

Enzyme-linked immunosorbent assay tests were performed to measure the IgG response to Nterm-34 kDa peptide in blood samples collected within a flavivirus seroprevalence survey carried out in 2006 including 3558 randomly selected individuals. The level of IgG response to the Nterm-34 kDa peptide in individuals was analysed in relation to the level of urbanisation of the individual's residence, areas that presented significant differences in the prevalence of recent DENV infection.

RESULTS

No differences were observed in the anti-Nterm-34 kDa IgG level between DENV-positive and DENV-negative individuals. However, the level of specific IgG response was higher among individuals living in slightly urbanised neighbourhoods than among those in more highly urbanised areas (P < 0.0001). Interestingly, a similar pattern had already been observed concerning the prevalence of recent DENV infection in the same populations.

CONCLUSION

The results of this retrospective study indicate that the evaluation of human IgG response to the Aedes Nterm-34 kDa salivary peptide could be a useful indicator to identify places with risk of dengue virus transmission in urban endemic areas.

Detection of homocysteine and C-reactive protein in the saliva of healthy adults: comparison with blood levels

Inflammation and cardiovascular disease are associated with elevated serum levels of C-Reactive Protein (CRP) and homocysteine. The presence of both molecules in saliva provides an opportunity for development of non-invasive assessments of disease risk. However, salivary CRP and homocysteine reference ranges and their correlation with serum levels are unknown. This study investigated if CRP and homocysteine could be routinely detected in the saliva of healthy adults and the relationship between salivary and blood levels. CRP and homocysteine concentrations were determined using ELISA and enzymatic assays respectively. Homocysteine was detected in only two saliva samples (n = 55). CRP was measurable in all saliva samples (range: 0.05 to 64.3 μg/L; median = 1.2 μg/L) and plasma samples (range: 0.14 to 31.1 mg/L; median = 2.0 mg/L). Regression analysis demonstrated no relationship between CRP concentration in saliva and plasma (R² = 0.001). Generalized linear models including variables such as saliva flow rate and time since eating or drinking also did not pass lack of fit testing. Therefore, a relationship between CRP concentration in saliva and blood could not be established in this group of subjects. More sensitive detection methods are needed to determine if a correlation between salivary and serum homocysteine levels exists.

Salivary transcriptomic biomarkers for detection of resectable pancreatic cancer

BACKGROUND & AIMS

Lack of detection technology for early pancreatic cancer invariably leads to a typical clinical presentation of incurable disease at initial diagnosis. New strategies and biomarkers for early detection are sorely needed. In this study, we have conducted a prospective sample collection and retrospective blinded validation to evaluate the performance and translational utilities of salivary transcriptomic biomarkers for the noninvasive detection of resectable pancreatic cancer.

METHODS

The Affymetrix HG U133 Plus 2.0 Array (Affymetrix, Santa Clara, CA) was used to profile transcriptomes and discover altered gene expression in saliva supernatant. Biomarkers discovered from the microarray study were subjected to clinical validation using an independent sample set of 30 pancreatic cancer patients, 30 chronic pancreatitis patients, and 30 healthy controls.

RESULTS

Twelve messenger RNA biomarkers were discovered and validated. The logistic regression model with the combination of 4 messenger RNA biomarkers (KRAS, MBD3L2, ACRV1, and DPM1) could differentiate pancreatic cancer patients from noncancer subjects (chronic pancreatitis and healthy control), yielding a receiver operating characteristic plot, area under the curve value of 0.971 with 90.0% sensitivity and 95.0% specificity.

CONCLUSIONS

The salivary biomarkers possess discriminatory power for the detection of resectable pancreatic cancer, with high specificity and sensitivity. This report provides the proof of concept of salivary biomarkers for the noninvasive detection of a systemic cancer and paves the way for prediction model validation study followed by pivotal clinical validation.

Bio/abiotic interface constructed from nanoscale DNA dendrimer and conducting polymer for ultrasensitive biomolecular diagnosis

For sensors detecting immobilized biomarkers, the interface between the surface and the fluid medium plays an important role in determining the levels of signal and noise in the electrochemical detection process. When protein is directly immobilized on the metal electrode, denaturation of the protein by surface-protein interaction results in low activity and low signal level. A conducting polymer-based interface can prevent the protein conformation change and alleviate this problem. A DNA dendrimer is introduced into the interfacial film on the sensor surface to further improve the sensor performance. DNA dendrimer is a nanoscale dendrite constructed of short DNA sequences, which can be easily incorporated into the abiotic conducting polymer matrix and is biocompatible with most biological species. In this work, DNA dendrimer and polypyrrole (DDPpy) form the bio/abiotic interface on electrochemical sensors. Detection of two salivary protein markers (IL-8 and IL-1beta) and one mRNA salivary marker (IL-8) is used to demonstrate the efficiency of the DDPpy sensor. A limit of detection (LOD) of protein of 100-200 fg mL(-1) is achieved, which is three orders of magnitude better than that without the DNA dendrimer interface. An LOD of 10 aM is established for IL-8 mRNA. The typical sample volume used in the detection is 4 microL, thus the LOD reaches only 25 target molecules (40 yoctomole).