Parameters of oxidative stress in saliva from diabetic and parenteral drug addict patients

Salivary gland proteins alterations in the diabetic milieu

Salivary glands are considered the chief exocrine glands of the mouth and physiologically contribute to the maintenance of the homeostasis of the oral cavity. They consist of the parotid, submandibular and sublingual glands, which come in pairs and are collectively called the major glands, and the minor glands, which are much smaller and are dispersed throughout the buccal cavity. Salivary glands are distinguished by their size, amount of saliva secretion and their location in the oral cavity. Salivary glands pathophysiology has been a subject of interest in various worldwide metabolic disorders, including diabetes mellitus. Diabetes mellitus (DM), a global health concern, with a pathological imprint involved in vasculature, promotes microvascular and macrovascular complications among which periodontitis ranks sixth. Indeed, DM has also been directly associated with oral health lesions. Specifically, salivary glands in the context of diabetes have been a focal point of study and emphasis in the research field. There is evidence that relates salivary secretion content and diabetes progression. In this review, we present all the reported evidence of the deregulation of specific salivary proteins associated with the progression of diabetes in parallel with changes in salivary gland morphology, cellular architecture, and salivary secretion and composition more generally.

Gemigliptin suppresses salivary dysfunction in streptozotocin-induced diabetic rats

Patients with diabetes commonly experience hyposalivation, which induces discomfort in eating, swallowing, dryness, smell, and speaking, as well as increases the incidence of periodontal disease. Dipeptidyl peptidase-4 (DPP4) inhibitors are frequently used as antidiabetic drugs that lower glucose levels by utilizing similar mechanisms; however, additional protective functions of each gliptin have been discovered. In this study, the protective roles of gemigliptin, a DPP4 inhibitor, against salivary dysfunction under diabetic conditions were investigated. Streptozotocin-induced diabetic rats received gemigliptin 10 mg/kg or 100 mg/kg via oral gavage for 3 weeks. The weights of salivary gland tissues, saliva secretion, and antioxidant capacity in salivary glands were reduced after diabetes induction, but were significantly preserved following gemigliptin treatment. In salivary gland analysis, expression of apoptotic proteins, as well as amylase and aquaporin-5 (AQP5) protein expression, were increased following gemigliptin treatment. Furthermore, the number of TUNEL-positive cells decreased after gemigliptin treatment. Therefore, gemigliptin has protective roles against salivary dysfunction observed in diabetes, mediated via antioxidant, anti-apoptotic, and salivary secretion mechanisms. These results may help in selecting a suitable drug for patients with diabetes experiencing salivary dysfunction.

Salivary and serum oxidative stress biomarkers and advanced glycation end products in periodontitis patients with or without diabetes: A cross-sectional study

BACKGROUND

Non-invasive methods for periodontitis diagnosis would be a clinically important tool. This cross-sectional study aimed to investigate the association between oxidative stress, glycation, and inflammation markers and periodontal clinical parameters in periodontitis and periodontally healthy patients with type 2 diabetes and corresponding systemically healthy controls.

METHODS

Sixty-seven periodontally healthy (DM-H, n = 32) and periodontitis (DM-P, n = 35) patients with type 2 diabetes, and 54 systemically healthy periodontitis (H-P, n = 26) and periodontally healthy (H-H, n = 28) controls were included. Clinical periodontal parameters, body mass index, fasting glucose, hemoglobin A1c (HbA1c), along with saliva and serum 8-hydroxy-2'-deoxyguanosine (8-OHdG), malondialdehyde (MDA), 4-hydroxy-2-nonenal (4-HNE), advanced glycation end products (AGE), AGE receptor (RAGE) and high sensitivity C-reactive protein (hsCRP) levels were recorded and analyzed.

RESULTS

Salivary 8-OHdG levels were significantly higher in periodontitis compared to periodontally healthy patients, regardless of systemic status (P < 0.001). Salivary MDA levels were significantly higher in all disease groups compared to H-H group (P ≤ 0.004). Serum AGE levels were significantly higher in diabetic groups than systemically healthy groups (P < 0.001) and in H-P compared to H-H (P < 0.001). Bleeding on probing (BOP) and clinical attachment level (CAL) strongly correlated with salivary 8-OHdG and serum hsCRP (P < 0.001). In systemically healthy patients, salivary 8-OHdG was the most accurate marker to differentiate periodontitis from controls (AUC = 0.84). In diabetics salivary 4-HNE and RAGE were the most accurate (AUC = 0.85 for both).

CONCLUSION

Salivary 8-OHdG alone or in combination with 4-HNE, AGE and RAGE for diabetics, and salivary 8-OHdG alone or in combination with MDA and hsCRP for systemically healthy persons, could potentially serve as non-invasive screening marker(s) of periodontitis.

Effects of vitamin C local application on ligature-induced periodontitis in diabetic rats

Objective:

This study evaluated the effects of local vitamin C treatment on tissue advanced glycation end products (AGE), interleukin (IL)-6, 8-hydroxy-2-deoxyguanosine (8-OHdG), and matrix metalloproteinases (MMP)-8 in tissues; serum C-terminal telopeptide fragments (CTX); and alveolar bone loss (ABL) in rats.

Methodology:

35 male Sprague Dawley rats were divided equally into five groups: 1) control (C), 2) experimental periodontitis (P), 3) experimental diabetes (D), 4) experimental diabetes and experimental periodontitis (D + P), and 5) experimental diabetes–experimental periodontitis–locally applied vitamin C (D + P + LvitC). Diabetes was induced in rats with alloxan monohydrate, after which periodontitis was induced by ligature placement in the right mandibular first molar teeth for 11 days. In the treatment group, vitamin C was administered locally three times with two-days interval after ligature removal. The animals were sacrificed, and the samples were analyzed histometrically and immunohistochemically.

Results:

CTX, 8-OHdG, and AGE values significantly decreased in the treatment group compared to the D + P group. IL-6 and MMP-8 values decreased in the treatment group compared to the D + P group, but this is not significant. ABL was significantly reduced by the local delivery of vitamin C.

Conclusion:

This study reveals that vitamin C treatment may be beneficial to reduce serum CTX and gingival MMP-8 levels, oxidative stress, inflammation, and AGE accumulation in periodontal tissue. Vitamin C may be an immunomodulator and antioxidant locally applied in the treatment of periodontitis to reduce the adverse effects of diabetes in periodontal tissues.

Correlation between the Activity of Aldehyde Dehydrogenase and Oxidative Stress Markers in the Saliva of Diabetic Patients

BACKGROUND

Reactive aldehydes are involved in diseases associated with oxidative stress, including diabetes. Human salivary aldehyde dehydrogenase (hsALDH) presumably protects us from many toxic ingredient/contaminant aldehydes present in food.

OBJECTIVE

This study aimed to probe the activity of hsALDH in patients with diabetes and than to correlate it with various oxidative stress markers in the saliva.

METHODS

The saliva samples were collected from total 161 diabetic patients from Rajiv Gandhi Centre for Diabetes, Jawaharlal Nehru Medical College (JNMC), AMU, Aligarh, (India). HsALDH activity and markers of oxidative stress [8-hydroxydeoxyguanosine (8-OHDG), malondialdehyde (MDA) and advanced glycation end products (AGEs)] were measured in the saliva samples.

RESULTS

Patients with early stage of diabetes had higher activity of hsALDH when compared with the control group. As the history of diabetes increases, the activity of the enzyme decreases and also higher oxidative stress markers (8-OHDG, MDA and AGEs) are detected in the saliva samples. Negative significant correlation between hsALDH activity and oxidative stress markers were observed (p <0.0001).

CONCLUSION

The activity of hsALDH increases in early stages of diabetes most probably to counter the increased oxidative stress associated with diabetes. However, in later stages of diabetes, the activity of the enzyme decreases, possibly due to its inactivation resulting from glycation.

Salivary 8-hydroxyguanosine levels in smokers and non-smokers with chronic periodontitis

This case-controlled clinical trial was performed on the salivary 8-hydroxyguanosine (8-OHdG) levels in smokers and non-smokers with chronic periodontitis after non-surgical periodontal therapy. Subjects (N = 40) with periodontitis (smokers and non-smokers) and with clinically healthy conditions (smokers and non-smokers) were assigned to this study. At baseline, clinical periodontal parameters (plaque index, gingival index, pocket probing depth and clinical attachment levels) were evaluated. Saliva samples were obtained pre- and post-treatment to quantify the 8-OHdG levels using Elisa technique. Subjects diagnosed with chronic periodontitis with smoking habit (CPs) and non-smokers (CPns) received scaling and root planing. In clinically healthy subjects with smoking habit (CHs) and non-smokers (CHns), only oral hygiene tutoring was performed. All clinical measurements and salivary collection were repeated in a 3-month recall interval. Data were analyzed using Anova, Tukey post hoc test and Mann-Whitney 'U' tests (P < 0.05). At baseline, CPs and CPns groups showed significantly higher PI, GI, PD and CAL values than those of CHns and CHs (P < 0.001). Baseline salivary levels of 8-OHdG were significantly higher in CPs group (14.775 pg/mL) (P < 0.001) compared to the other groups. All clinical parameters in chronic periodontitis group improved at the 3rd month recall interval, however, with regards to 8-OHdG values, the CP smoker category still had a higher level compared to CP non-smoker. This study reflects an on-going periodontal destructive status in smokers and salivary 8-OHdG levels could be recognized as an oxidative biomarker for determining periodontal tissue destruction.

Influence of Sampling Conditions, Salivary Flow, and Total Protein Content in Uric Acid Measurements in Saliva

Uric acid (UA) is the most abundant antioxidant compound in saliva and one of the most sensitive biomarkers for detecting changes in the oxidative status of the organism. The aim of this study was to evaluate the effect of: (i) different methods of saliva sampling and (ii) the correction by salivary flow or total protein on UA concentrations in saliva. Paired saliva (collected by two different methods, passive drooling and using Salivette cotton rolls) and serum samples were obtained from 12 healthy men after the performance of two resistance training exercises of different level of effort that can produce different concentrations in UA in saliva. There were no significant differences between values of uric acid in saliva using Salivette and passive drool. Correlations between UA in serum and saliva and increases in UA in saliva after exercise were detected when saliva samples were obtained by passive drool and Salivette and were not corrected by salivary flow or total protein concentration. Therefore for UA measurements in saliva it would not be recommended to normalize the results by salivary flow or protein concentration. This study highlights the importance of choosing an adequate sampling method selection as well as the expression of results when analytes are measured in saliva.

Supraphysiologic-dose anabolic-androgenic steroid use: A risk factor for dementia?

Supraphysiologic-dose anabolic-androgenic steroid (AAS) use is associated with physiologic, cognitive, and brain abnormalities similar to those found in people at risk for developing Alzheimer's Disease and its related dementias (AD/ADRD), which are associated with high brain β-amyloid (Aβ) and hyperphosphorylated tau (tau-P) protein levels. Supraphysiologic-dose AAS induces androgen abnormalities and excess oxidative stress, which have been linked to increased and decreased expression or activity of proteins that synthesize and eliminate, respectively, Aβ and tau-P. Aβ and tau-P accumulation may begin soon after initiating supraphysiologic-dose AAS use, which typically occurs in the early 20s, and their accumulation may be accelerated by other psychoactive substance use, which is common among non-medical AAS users. Accordingly, the widespread use of supraphysiologic-dose AAS may increase the numbers of people who develop dementia. Early diagnosis and correction of sex-steroid level abnormalities and excess oxidative stress could attenuate risk for developing AD/ADRD in supraphysiologic-dose AAS users, in people with other substance use disorders, and in people with low sex-steroid levels or excess oxidative stress associated with aging.

Buprenorphine and Methadone as Opioid Maintenance Treatments for Heroin-Addicted Patients Induce Oxidative Stress in Blood

Buprenorphine and methadone are two substances widely used in the substitution treatment of patients who are addicted to opioids. Although it is known that they partly act efficiently towards this direction, there is no evidence regarding their effects on the redox status of patients, a mechanism that could potentially improve their action. Therefore, the aim of the present investigation was to examine the impact of buprenorphine and methadone, which are administered as substitutes to heroin-dependent patients on specific redox biomarkers in the blood. From the results obtained, both the buprenorphine (n = 21) and the methadone (n = 21) groups exhibited oxidative stress and compromised antioxidant defence. This was evident by the decreased glutathione (GSH) concentration and catalase activity in erythrocytes and the increased concentrations of thiobarbituric acid reactive substances (TBARS) and protein carbonyls in the plasma, while there was no significant alteration of plasma total antioxidant capacity (TAC) compared to the healthy individuals (n = 29). Furthermore, methadone revealed more severe oxidant action compared to buprenorphine. Based on relevant studies, the tested substitutes mitigate the detrimental effects of heroin on patient redox status; still it appears that they need to be boosted. Therefore, concomitant antioxidant administration could potentially enhance their beneficial action, and most probably, buprenorphine that did not induce oxidative stress in such a severe mode as methadone, on the regulation of blood redox status.

The effect of periodontal therapy on oxidative stress biomarkers: A systematic review

AIM

To systematically review the literature about the effect of periodontal treatment on oxidative stress (OxS) biomarkers.

MATERIAL AND METHODS

Three databases (PubMed, EMBASE, and Scopus) were searched up to February 2018. Clinical trials with a follow-up of at least 6 weeks after mechanical periodontal treatment were included. Due to the high heterogeneity among the units and indices of measurements used in the studies, a meta-analysis was not performed.

RESULTS

Overall, 3,199 studies were retrieved, of which 20 were included. Four studies were randomized clinical trials (RCT), and 16 studies were non-RCTs. The most common OxS biomarkers used were 8-hydroxydeoxiguanosine (8-OHdG), total oxidant status (TOS), and total antioxidant status (TAS). After treatment, most of the studies reported a decrease in 8-OHdG concentration in the gingival crevicular fluid (GCF) and saliva. In addition, the salivary concentration of this biomarker was similar to periodontally healthy patients. Periodontal therapy was effective in reducing TOS in GCF, saliva, and serum in most studies. TAS, however, responded inconsistently to the periodontal intervention.

CONCLUSION

Periodontal therapy reduces the levels of OxS biomarkers, even to values similar to those found in periodontally healthy individuals. Additional RCTs are warranted, as the information is mainly based on nonrandomized studies.

Fluorescence Determination of Glutathione Using Tissue Paper-derived Carbon Dots as Fluorophores

Glutathione is an important antioxidant found in body fluids and tissues, which inhibit damage to essential cellular constituents caused by reactive oxygen species. The analysis of glutathione levels in biological systems is important in early clinical diagnosis. A novel, cost-effective synthetic strategy has been developed for the fluorescent probe ethylenediamine passivated carbon dots. Tissue paper was chosen as the carbon source for this "green one pot" synthesis. Glutathione could induce quenching of the fluorescence intensity of ethylenediamine passivated carbon dots through surface interactions, resulting from their aggregation. Based on this, a novel fluorescence sensor was fabricated for the determination of Glutathione in body fluids. A linear calibration graph was obtained in the range of 6.0 × 10^-7 to 5.0 × 10^-8 M with a detection limit of 1.74 × 10^-9 M. The developed sensor was successfully used for the determination of glutathione in artificial saliva samples.

Chemical analysis in saliva and the search for salivary biomarkers – a tutorial review

A review of the uses of saliva biomarkers, detection methods and requirements for new biomarkers.

Salivary gland hypofunction in KK-Ay type 2 diabetic mice

BACKGROUND

Hypofunction of different organs in the body is associated with diabetes, including in the oral cavity. Diabetes is often associated with xerostomia, but the underlying mechanism is not well characterized. Thus, the mechanisms underlying diabetes-induced xerostomia were investigated in this study in KK-A ^y mice as an experimental model of type 2 diabetes.

METHODS

The mechanisms involved in diabetes-induced xerostomia were investigated using the ex vivo glandular perfusion technique, histological analysis, and immunohistochemical and intracellular signaling analyses.

RESULTS

Ex vivo submandibular gland secretions from KK-A^y mice decreased by 30% following stimulation with 0.3 μmol/L carbachol (CCh), a cholinergic agonist. Acinar cell weight was comparable between KK-A^y and control mice, whereas duct cell weight was significantly greater in KK-A^y mice. Concentrations of Na⁺ and Cl^- in the secreted saliva decreased significantly in KK-A^y mice, supporting the finding of increased ductal tissue in KK-A^y mice. Immunohistochemistry revealed no significant differences between KK-A^y and control mice in terms of the expression of Cl^- and water channels, Na⁺ -K⁺ -2Cl^- cotransporters, and membrane proteins critical for fluid secretion. Cellular signaling analysis revealed that the increase in [Ca²⁺ ]_i in response to 0.3 μmol/L CCh was reduced by 30% in KK-A^y mice, although there was no significant difference in the thapsigargin (1.0 μmol/L)-induced increase in store-depleted calcium between KK-A^y and control mice.

CONCLUSIONS

These results demonstrate that submandibular fluid secretion is diminished in KK-A^y mice because of a diminished increase in [Ca²⁺ ]_i . Duct cell weight increased in KK-A^y mice, possibly leading to increased ion reabsorption and thus decreased Na⁺ and Cl^- concentrations in the secreted saliva.

Salivary protective factors in patients suffering from decompensated type 2 diabetes

PURPOSE

Defining the level of protective factors in saliva of patients suffering from decompensated type 2 diabetes.

MATERIAL AND METHODS

50 Patients with diagnosis of decompensated type 2 diabetes, including 32 women and 18 men at the age of 57.9±9.2 years. The control group consisted of 50 people among whom there were 38 women and 12 men whose average age was estimated at 51.2±9.9 years.

RESULTS

It was stated the increased concentration of total protein by 60% and decreased concentration of IgA by 70%, of lysozyme by 27% and of lactoferrin by 40% in resting saliva of patients with type 2 diabetes if compared to the control group. These outcomes were really statistically meaningful. The evaluation of dependences between the analyzed protective factors and the indicator of oral cavity condition proved the positive correlation between the concentration of total protein and the number of DMFT (i.e. the rate of caries intensity). The remaining coefficients of correlation being evaluated proved to be negative and statistically meaningless.

CONCLUSION

The obtained outcomes prove a high influence of proteins included in saliva on the prevalence and development of caries at patients with decompensated type 2 diabetes.

Increased salivary oxidative stress parameters in patients with type 2 diabetes: Relation with periodontal disease

OBJECTIVE

The aim of this study was to determine whether there are differences in salivary oxidative stress between patients with diabetes mellitus type 2 (DM2) and healthy non-diabetic patients, and whether this oxidative stress is associated with the presence of periodontal disease in diabetic patients.

MATERIAL AND METHODS

This observational study included 70 patients divided into three groups according to metabolic control levels: 19 non-diabetic patients (control group); 24 patients with good metabolic control (HbA1c<7%), and 27 patients DM2 with poor metabolic control (HbA1c>7%). The following oxidative stress parameters were measured in all subjects: glutathione peroxidase (GPx), glutathione reductase (GRd), reduced glutathione (GSH) and oxidized glutathione (GSSG). Periodontal health was determined by means of the community periodontal index (CPI) recommended by the WHO.

RESULTS

The diabetic group with good metabolic control showed a significant increase in GPx and GRd activity in comparison with the control group (P<.001). The activity of the enzymes measured was significantly less in patients with poor metabolic control in comparison with the control group and well-controlled diabetic groups (P<.001). Both diabetic groups showed higher GSSG/GSH quotients and CPI in comparison with the control group, and both parameters were significantly higher in diabetic patients with poor metabolic control in comparison with well-controlled diabetic patients.

CONCLUSIONS

Poor metabolic control in DM2 patients is associated with higher levels of salivary oxidative stress and worse periodontal health.

Brain-derived neurotrophic factor (BDNF) and oxidative stress in heroin-dependent male patients undergoing methadone maintenance treatment

Brain-derived neurotrophic factor (BDNF) and oxidative stress may play a role in patients with heroin dependence. The aim of this study was to investigate the serum levels and activities of BDNF and oxidative stress markers, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), thiobarbituric acid reactive substances (TBARS), protein carbonyl content (PCC), and 8-hydroxy 2'-deoxyguanosine (8-OHdG), in heroin-dependent patients undergoing methadone maintenance treatment (MMT). 60 heroin-dependent male MMT patients and 30 healthy males were recruited for this study. The serum BDNF and oxidative stress markers of these subjects were measured with assay kits. Analyses of covariance (ANCOVAs) with age and body mass index adjustments indicated that the serum levels of BDNF in the MMT patients were significantly higher than those in the healthy controls (F=5.169; p=0.026). However, there were no significant differences between the heroin-dependent patients and the healthy controls in the serum levels or activities of oxidative stress markers (p>0.05). In conclusion, our results suggest that MMT increases BDNF levels in heroin-dependent patients, and that patients undergoing MMT might be in a balanced state of reduced oxidation.

Comparative analysis of the oxidative stress and antioxidant status in type II diabetics and nondiabetics: A biochemical study

Background:

Diabetes mellitus is a metabolic disorder characterized by hyperglycemia along with biochemical alterations of glucose and lipid peroxidation. It produces free radicals that induce lipid peroxidation which acts as an indicator for oxidative stress in the body. The widely used assay for lipid peroxidation involves measurement of malondialdehyde (MDA). Defensive system in the body consists of antioxidant enzymes which help in scavenging free radicals. Two such antioxidant enzymes are reduced glutathione (GSH) and superoxide dismutase (SOD). In this study MDA, GSH and SOD are assessed in serum and saliva of age- and sex-matched 33 diabetics and nondiabetics.

Objective:

(1) To estimate the levels of MDA, GSH and SOD in saliva and serum of both diabetics and nondiabetics. (2) To correlate the levels of MDA, GSH and SOD in saliva and serum of both diabetics and nondiabetics. (3) To find if serum levels of MDA, GSH and SOD can be predicted from values of the same in saliva, in both groups.

Materials and Methods:

Whole unstimulated saliva and venous blood samples obtained after 12 h of overnight fast were transported to the designated laboratory chosen for the study. Supernatants of the centrifuged samples were used for the assays of MDA, GSH and SOD.

Results:

A significant correlation was obtained between serum and saliva values of MDA and GSH, hence the prediction of serum MDA and GSH was possible from their subsequent saliva values. Although the levels of serum and salivary SOD showed a weak positive correlation, prediction of SOD was not possible.

Conclusion:

Saliva can be used as a diagnostic tool for the estimation of MDA, GSH and SOD.

Evaluation of salivary oxidative parameters in overweight and obese young adults

Background

Obesity is characterized by a deposition of abnormal or excessive fat in adipose tissue, and is linked with a risk of damage to several metabolic and pathological processes associated with oxidative stress. To date, salivary oxidative biomarkers have been minimally explored in obese individuals. Thus, the aim of this study was to assess the concentrations of salivary oxidative biomarkers (ferric-reducing antioxidant power, uric acid, sulfhydryl groups) and lipid peroxidation in obese and overweight young subjects.

Materials and methods

Levels of lipid peroxidation, ferric-reducing antioxidant power, uric acid, and SH groups were determined in the saliva and serum of 149 young adults, including 54 normal weight, 27 overweight, and 68 obese individuals. Anthropometric measurements were also evaluated.

Results

Salivary levels of ferric-reducing antioxidant power, sulfhydryl groups, and lipid peroxidation, as well as serum levels of ferric-reducing antioxidant power, uric acid, and lipid peroxidation were higher in obese patients when compared with individuals with normal weight. There were correlations between salivary and serum ferric-reducing antioxidant power and salivary and serum uric acid in the obese and normal-weight groups.

Conclusions

Our results indicate that the increase in salivary levels of ferric-reducing antioxidant power, sulfhydryl groups, and lipid peroxidation, and serum levels of ferric-reducing antioxidant power, uric acid, and lipid peroxidation could be related to the regulation of various processes in the adipose tissue. These findings may hold promise in identifying new oxidative markers to assist in diagnosing and monitoring overweight and obese patients.

Impact of non-surgical periodontal therapy on saliva and serum levels of markers of oxidative stress

OBJECTIVE

The purpose of this study was to determine the effect of non-surgical periodontal treatment on markers of oxidative stress in saliva and serum in patients with chronic periodontitis.

MATERIALS AND METHODS

In total, 25 patients, who were diagnosed with generalized chronic periodontitis (11 females and 14 males), and 26 systemically and periodontally healthy individuals (15 females and 11 males) were included. The plaque index (PI), gingival index (GI), probing pocket depth (PPD), attachment loss (AL), gingival recession (GR), and bleeding on probing (BOP) were recorded at baseline and 6 weeks later. Malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and 4-hydroxy-2-nonenal (4-HNE) were assessed in saliva and serum samples before and after the non-surgical treatment by enzyme-linked immune sorbent assay (ELISA).

RESULTS

In the group with chronic periodontitis, all clinical parameters were significantly higher compared to the control group at baseline (p < 0.001). Periodontal treatment reduced plaque, gingival inflammation, and pocket depth significantly (p < 0.001). At baseline, salivary 8-OHdG was significantly higher in chronic periodontitis (p < 0.001) and reduced significantly subsequent to the periodontal treatment (p < 0.001). Salivary MDA and serum 4-HNE were significantly higher in the patients with periodontitis compared to the control group (p < 0.001). Periodontal treatment did not significantly change the levels of 4-HNE and salivary MDA (p = 0.503, p = 0.093).

CONCLUSIONS

Salivary 8-OHdG and MDA may be associated with local impact of periodontal disease, while 4-HNE may be associated with systemic impact of chronic periodontitis.

CLINICAL RELEVANCE

Clinical intervention in periodontitis may be beneficial for periodontitis patients' systemic oxidative stress control, and using lipidic agents for the use of anti-inflammatory/pro-resolving processes for blocking the actions of arachidonic acid cascade can enable some late therapeutic strategies in order to lead oxidative stress-induced inflammation.

Assessment of salivary total antioxidant capacity in patients with primary untreated head and neck squamous cell carcinoma with ORAC

BACKGROUND

Oxidative DNA damage leads to abnormalities in endogenous cellular processes and constitutes a direct link between free radicals, antioxidants and squamous cell carcinoma (SCC). Oxygen radical absorbance capacity (ORAC) method is used to measure antioxidant capacity versus oxygen free radicals. There is no report on the application of ORAC to evaluate salivary antioxidant capacity in patients with head and neck SCC. This study investigated the relation between total antioxidant capacity of saliva, measured with ORAC method, and the incidence, location, size and histopathological grading of SCC.

METHODS

Salivary antioxidant capacity was assessed in 30 male and female patients with histopathologically confirmed oral and laryngeal SCC. Histopathological grading of SCC was based on WHO classification.

RESULTS

Mean ORAC in patients with SCC was higher than the mean value in the control group. Statistically significant difference was observed in the study group versus the control group. No significant differences were observed for ORAC values in relation to histopathological grading, tumour size and spread to lymph nodes.

CONCLUSIONS

The obtained results can advocate local compensatory mechanism in saliva in response to increased oxidative stress associated with primary tumour. ORAC can become an additional factor in head and neck SCC prognosis, but further investigation is required.

Non-invasive detection of fasting blood glucose level via electrochemical measurement of saliva

Machine learning techniques such as logistic regression (LR), support vector machine (SVM) and artificial neural network (ANN) were used to detect fasting blood glucose levels (FBGL) in a mixed population of healthy and diseased individuals in an Indian population. The occurrence of elevated FBGL was estimated in a non-invasive manner from the status of an individual’s salivary electrochemical parameters such as pH, redox potential, conductivity and concentration of sodium, potassium and calcium ions. The samples were obtained from 175 randomly selected volunteers comprising half healthy and half diabetic patients. The models were trained using 70 % of the total data, and tested upon the remaining set. For each algorithm, data points were cross-validated by randomly shuffling them three times prior to implementing the model. The performance of the machine learning technique was reported in terms of four statistically significant parameters—accuracy, precision, sensitivity and F1 score. SVM using RBF kernel showed the best performance for classifying high FBGLs with approximately 85 % accuracy, 84 % precision, 85 % sensitivity and 85 % F₁ score. This study has been approved by the ethical committee of All India Institute of Medical Sciences, New Delhi, India with the reference number: IEC/NP-278/01-08-2014, RP-29/2014.

Comparison of Aerobic Preservation by Venous Systemic Oxygen Persufflation or Oxygenated Machine Perfusion of Warm-Ischemia-Damaged Porcine Kidneys

Background/Aim: The global shortage of donor organs for transplantation has necessitated the expansion of the organ pool through increased use of organs from less ideal donors. Venous systemic oxygen persufflation (VSOP) and oxygenated machine perfusion (OMP) have previously demonstrated beneficial results compared to cold storage (CS) in the preservation of warm-ischemia-damaged kidney grafts. The aim of this study was to compare the efficacy of VSOP and OMP for the preservation of warm-ischemia-damaged porcine kidneys using the recently introduced Ecosol preservation solution compared to CS using Ecosol or histidine-tryptophan-ketoglutarate solution (HTK). Materials and Methods: Kidneys from German Landrace pigs (n = 5/group) were retrieved and washed out with either Ecosol or HTK after 45 min of clamping of the renal pedicle. As controls, kidneys without warm ischemia, cold stored for 24 h in HTK, were employed. Following 24 h of preservation by VSOP, OMP, CS-Ecosol, or CS-HTK, renal function and damage were assessed during 1 h using the isolated perfused porcine kidney model. Results: During reperfusion, urine production was significantly higher in the VSOP and OMP groups than in the CS-HTK group; however, only VSOP could demonstrate lower urine protein concentrations and fractional excretion of sodium, which did not differ from the non-warm-ischemia-damaged control group. VSOP, CS-Ecosol, and controls showed better maintenance of the acid-base balance than CS-HTK. Reduced lipid peroxidation, as reflected in postreperfusion tissue thiobarbituric acid-reactive substance levels, was observed in the VSOP group compared to the OMP group, and the VSOP and CS-Ecosol groups had concentrations similar to the controls. The ratio of reduced to oxidized glutathione was higher in the VSOP, OMP, and CS-Ecosol groups than in the CS-HTK group and controls, with a higher ratio in the VSOP than in the OMP group. Conclusion: VSOP was associated with mitigation of oxidative stress in comparison to OMP and CS. Preservation of warm-ischemia-damaged porcine kidneys by VSOP was improved compared to OMP and CS, and was comparable to preservation of non-warm-ischemia-damaged cold-stored kidneys.

Detection of inflammatory biomarkers in saliva and urine: Potential in diagnosis, prevention, and treatment for chronic diseases

Inflammation is a part of the complex biological response of inflammatory cells to harmful stimuli, such as pathogens, irritants, or damaged cells. This inflammation has been linked to several chronic diseases including cancer, atherosclerosis, rheumatoid arthritis, and multiple sclerosis. Major biomarkers of inflammation include tumor necrosis factor, interleukins (IL)-1, IL-6, IL-8, chemokines, cyclooxygenase, 5-lipooxygenase, and C-reactive protein, all of which are regulated by the transcription factor nuclear factor-kappaB. Although examining inflammatory biomarkers in blood is a standard practice, its identification in saliva and/or urine is more convenient and non-invasive. In this review, we aim to (1) discuss the detection of these inflammatory biomarkers in urine and saliva; (2) advantages of using salivary and urinary inflammatory biomarkers over blood, while also weighing on the challenges and/or limitations of their use; (3) examine their role(s) in connection with diagnosis, prevention, treatment, and drug development for several chronic diseases with inflammatory consequences, including cancer; and (4) explore the use of innovative salivary and urine based biosensor strategies that may permit the testing of biomarkers quickly, reliably, and cost-effectively, in a decentralized setting.

Role of salivary malondialdehyde in assessment of oxidative stress among diabetics

AIMS

To evaluate and compare the salivary content of malondialdehyde (MDA) in patients with type 2 diabetes and control subjects.

METHODS

We conducted a cross-sectional study among 30 freshly diagnosed subjects of diabetes mellitus and 30 volunteers with no diabetes mellitus. Serum and salivary MDS levels were evaluated among all the subjects.

RESULTS

The mean serum MDA in group controls and diabetics was 0.95 ± 0.13 and 3.11 ± 0.42. The mean salivary MDA in group controls and diabetics was 0.26 ± 0.05 μmol/l and 0.81 ± 0.07 μmol/l. The mean serum and salivary MDA levels were significantly higher in group diabetics than control group (p < 0.001 and <0.001) respectively. There was significant positive strong correlation between serum and salivary MDA levels in both controls and diabetics groups (r = 0.857, p < 0.001 and r = 0.891, p < 0.001) respectively.

CONCLUSION

MDA was detectable in saliva in both diabetic and control groups. There was a positive significant correlation between salivary and serum MDA in diabetic and control subjects. Hence, salivary MDA appears to be an indicator of serum MDA concentration.

Can saliva testing replace blood measurements for health monitoring? Insights from a correlation study of salivary and whole blood glutathione in humans

The feasibility of using saliva samples as diagnostic for health status is assessed.

Aphthous ulcers, salivary peroxidase and stress: Are they related?

Background:

In today's high strung lifestyle, stress plays a major role on our health. Studies using ultraweak chemiluminescence have been able to demonstrate this effect, of psychological stress on the immune system, using saliva as a psychological stress marker. The impact of psychosocial factors on the oral mucosal lesions of individuals found that stress can contribute to weakened immunity and increased susceptibility to infection.

Aim:

To study the role of salivary peroxidase (SPOx) in psychologically stressed individuals with and without the presence of aphthous ulcer.

Materials and Methods:

The study involved evaluating subjects for stress, using Perceived Stress Scale. Depending on the stress scores and the presence or absence of oral aphthae, they were assigned into 3 groups of 30 each. After a thorough oral examination, individual samples of saliva was collected and subjected to microprotein estimation using a biochemical analyzer.

Statistical Analysis Used:

Analysis of variance (ANOVA) and Student's t-test.

Results:

Decreased levels of peroxidase were found in individuals’ with aphthous ulcers, while the same was increased when no lesions were found and also on a lower stress scale.

Conclusions:

Our study analysis does show a variation in enzyme levels between the different groups highlighting the influence of stress on the peroxidase levels, which in turn when imbalanced, results in tissue damage, leading to aphthous formation.

Clinical and diagnostic utility of saliva as a non-invasive diagnostic fluid: a systematic review

This systematic review presents the latest trends in salivary research and its applications in health and disease. Among the large number of analytes present in saliva, many are affected by diverse physiological and pathological conditions. Further, the non-invasive, easy and cost-effective collection methods prompt an interest in evaluating its diagnostic or prognostic utility. Accumulating data over the past two decades indicates towards the possible utility of saliva to monitor overall health, diagnose and treat various oral or systemic disorders and drug monitoring. Advances in saliva based systems biology has also contributed towards identification of several biomarkers, development of diverse salivary diagnostic kits and other sensitive analytical techniques. However, its utilization should be carefully evaluated in relation to standardization of pre-analytical and analytical variables, such as collection and storage methods, analyte circadian variation, sample recovery, prevention of sample contamination and analytical procedures. In spite of all these challenges, there is an escalating evolution of knowledge with the use of this biological matrix.

Effect of initial periodontal therapy on oxidative stress markers in gingival crevicular fluid, saliva, and serum in smokers and non-smokers with chronic periodontitis

BACKGROUND

The aim of this case-control study with an intervention arm is to determine the effect of initial periodontal treatment on oxidative stress biomarkers in smokers and non-smokers with chronic periodontitis (CP).

METHODS

The study included 47 patients with CP (24 smokers [S+P+] and 23 non-smokers [S-P+]) and 46 periodontally healthy individuals (23 smokers [S+P-] and 23 non-smokers [S-P-]) for a total of 93 participants. Gingival crevicular fluid (GCF), serum, and saliva samples were obtained and clinical periodontal measurements were recorded at baseline and at the first and third months after periodontal therapy. 8-hydroxydeoxyguanosine (OHdG) and 4-hydroxynonenal (HNE) and enzyme activity of glutathione peroxidase (GSH-Px) were analyzed with enzyme-linked immunosorbent assay.

RESULTS

The level of 8-OHdD in GCF was found to be significantly higher in both periodontitis groups compared with both periodontally healthy groups. 8-OHdG and GSH-Px in saliva in both periodontitis groups were significantly increased compared with the S-P- group. In the S+P+ group, 4-HNE in GCF was found to be significantly higher than in periodontally healthy participants. After initial periodontal treatment, the levels of 8-OHdG in GCF and saliva were significantly decreased in both periodontitis groups.

CONCLUSION

Initial periodontal therapy may be helpful for diminishing oxidative stress in periodontitis.

Determination of storage time of saliva samples obtained from patients with and without chronic periodontitis for the comparison of some biochemical and cytological parameters

BACKGROUND

Salivary glutathione (GSH), malondialdehyde (MDA), protein, sialic acid (SA) levels, cytological parameters, and tissue factor activities (TFa) were investigated when fresh and after 3, 7, 11, 15, 21, and 30 days (d) of storage at -20°C both in the control and the periodontitis group. Moreover, the control and the periodontits groups were compared and continuity of the significances detected between the two groups were evaluated.

METHODS

GSH, MDA, SA, protein, and TFa were determined using the methods of Beutler, Yagi, Warren, Lowry, and Quick, respectively. Saliva imprint samples were stained with Giemsa and microscopically examined.

RESULTS

When the continuity of the significances of differences between the two groups was investigated, differences continued to be significant for GSH and TFa on days 3, 7, 11, 15, 21, and 30. Cytologically, only the significance detected between leucocyte numbers continued to be significant for 30 d. However significance of differences in total protein, MDA, and SA levels on day 0, were interrupted on days 3, 7, and 11, respectively.

CONCLUSION

Saliva samples may be stored for 30 d for GSH and TFa analyses in patients with and without periodontitis. However, to compare salivary MDA, SA, and total protein levels in these groups we suggest fresh samples to be studied.

No harmful effect of different Coca-cola beverages after 6 months of intake on rat testes

Our laboratory recently reported that a 3-month exposure of rats to cola-like beverages induced sex hormone changes. The aim of the study was to investigate the effects of various types of Coca-cola intake with different composition for 6 months on oxidative status in testes and testosterone in adult male rats. Fifty adult male Wistar rats were divided into control group drinking water, and groups drinking different Coca-cola beverages (regular Coca-cola, Coca-cola caffeine-free, Coca-cola Light and Coca-cola Zero). Oxidative and carbonyl stress markers were measured in the testicular tissue to assess oxidative status together with testicular and plasma testosterone. StAR expression in testes as a marker of steroidogenesis was quantified. No significant differences were found between the groups in any of the measured parameters. In conclusion, oxidative and carbonyl stress in testicular tissue were not influenced by drinking any type of Coca-cola. Additionally, testosterone in testes and in plasma, as well as testicular StAR expression were comparable among the groups.

The effects of opiate consumption on serum reproductive hormone levels, sperm parameters, seminal plasma antioxidant capacity and sperm DNA integrity

We evaluated the effects of opiate consumption on semen quality, sperm function, seminal plasma antioxidant capacity, and sperm DNA integrity. A total of 142 opiate addict men (group 1) were enrolled in the study and 146 healthy age matched male volunteers (group 2) served as controls. Two semen analyses were performed in all participants. Sperm chromatin structure assay (SCSA) was used to identify sperm DNA integrity. The mean±SD sperm concentration in opiate users and in control subjects was 22.2±4.4 and 66.3±8.3 million per ml, respectively (P=0.002). A significant increase in the amount of fragmented DNA was found in opiate consumers compared with that in controls (36.4±3.8% vs. 27.1±2.4%, P=0.004). Significantly decreased levels of catalase-like and superoxide dismutase-like (SOD) activity were observed in group 1 compared with group 2. Opiate consumption has significant adverse effects on semen quality. In cases of unexplained infertility in men, opium consumption should be considered as a possible factor.

Salivary markers of oxidative stress in patients with oral premalignant lesions

The aetiology of oral premalignant lesions is unknown. Oxidative stress is associated with inflammation and cancerogenesis. The aim of our study was to compare salivary markers of oxidative and carbonyl stress in patients with oral premalignant lesions and age-matched healthy controls. Unstimulated saliva samples were collected from 16 patients with oral premalignant lesions (leukoplakia, lichen planus, erythroplakia) and 16 age-matched healthy controls. Biochemical analysis included measurement of thiobarbituric acid reacting substances (TBARS), advanced oxidation protein products (AOPP), advanced glycation endproducts (AGEs) and total antioxidant capacity (TAC). Salivary RNA was analyzed using real time PCR. Salivary TBARS and AGEs were significantly higher in patients than in controls. No differences were found in AOPP. TAC and expression of superoxide dismutase were lower in patients than in age-matched controls. Other analyzed transcripts (vascular endothelial growth factor, sialotransferase, neuraminidase) did not differ between patients and the control group. Markers of lipoperoxidation and carbonyl stress were increased in patients with oral premalignant lesions. Decreased antioxidant status potentially due to decreased expression of antioxidant enzymes might be responsible for these findings. Our results might point to the aetiology or pathogenesis of oral premalignant lesions as well as to the mechanism of transition to oral carcinoma.

8-hydroxy-deoxyguanosine levels in gingival crevicular fluid and saliva in patients with chronic periodontitis after initial periodontal treatment

BACKGROUND

This study evaluates the effects of initial periodontal treatment on the gingival crevicular fluid (GCF) and salivary levels of 8-hydroxy-deoxyguanosine (8-OHdG) as a marker of oxidative deoxyribonucleic acid (DNA) damage in patients with chronic periodontitis (CP).

METHODS

At baseline, clinical parameters were determined and GCF and saliva samples were obtained from 24 patients with CP and 24 individuals with clinically healthy periodontium. GCF, saliva samples, and clinical periodontal measurements were repeated at day 10, 1 month, and 3 months following initial periodontal therapy in patients with CP. 8-OHdG levels of GCF and saliva samples were investigated by using an enzyme-linked immunosorbent assay.

RESULTS

Statistically significant higher 8-OHdG levels of GCF and a significant decrease after initial periodontal therapy were determined in the CP group (P <0.001). A significant positive correlation was found between 8-OHdG levels of GCF and clinical periodontal measurements (P <0.001). However, salivary levels of 8-OHdG did not differ between groups or during initial periodontal therapy (P >0.05).

CONCLUSIONS

This study reveals that DNA injury and oxidative stress increase in tissue cells and especially in periodontal pockets in patients with CP, and the periodontal treatment results in a significant decrease of 8-OHdG levels in the GCF samples. To the best of our knowledge, this study evaluates for the first time, 8-OHdG levels in GCF, which is shown to be more useful as a biomarker than saliva. 8-OHdG was found to be important and may reveal the severity of periodontal disease and the effect of periodontal therapy.

Salivary lipid peroxidation and total sialic acid levels in smokers and smokeless tobacco users as Maraş powder

Maraş powder (MP), a different type of smokeless tobacco (ST) and prepared from a tobacco of species Nicotiana rustica Linn, is widely used in Turkey. We aimed to investigate the effects of MP on salivary total sialic acid (TSA) and malondialdehyde (MDA) levels and to compare these parameters in smokers and MP users (MPUs). The salivary TSA and MDA concentrations were significantly higher in the smokers and MPU than those of control subjects and also in MPU than that of smokers. We have also observed that as the number of cigarettes consumed and MP amount increases, TSA and MDA levels increase too. In smokers, MDA values were significantly correlated with the number of cigarettes smoked and the duration of smoking. In MPU, both MDA and TSA levels were significantly correlated with the duration of MP use and the amount of daily consumed MP. We have concluded increased salivary TSA and MDA levels associated in MPU and smokers. Results can help to evaluate harmful effects of these habits. It is important to point out that bigger change in the measured parameters has been observed for MP use. This observation may be an important indication of harmful effects of ST use as MP.

Altered redox homeostasis in human diabetes saliva

BACKGROUND

Oxidative stress has been implicated in the pathogenesis of diabetes mellitus (DM). Levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-epi-prostaglandin-F(2α) (8-epi-PGF2α), and total protein carbonyls were measured to assess whether DM is associated with altered salivary redox homeostasis.

METHODS

A total of 215 patients with diabetes and 481 healthy controls were recruited from the Department of Endocrinology at the Jewish General Hospital in Montreal. Levels of oxidative biomarkers were assayed using enzyme-linked immunosorbent assay (ELISA) in whole unstimulated saliva. Associations of the redox data with exposure to insulin, metformin and dietary control were assessed by logistic regression analyses.

RESULTS

We observed (i) significantly higher mean levels of 8-OHdG and protein carbonyls in whole unstimulated saliva of patients with diabetes compared to controls, (ii) higher mean levels of protein carbonyls in type 1 diabetes as well as higher mean levels of 8-OHdG and protein carbonyls in type 2 diabetes compared to controls, (iii) elevated levels of protein carbonyls in diet-controlled patients and in patients with diabetes on insulin and metformin, (iv) elevated levels of 8-OHdG in patients on metformin, and (v) significant associations between subjects with DM and salivary 8-OHdG and protein carbonyls.

CONCLUSION

DM is associated with increased oxidative modification of salivary DNA and proteins. Salivary redox homeostasis is perturbed in DM and may inform on the presence of the disease and efficacy of therapeutic interventions.

Gene expression profiles of the three major salivary glands in rats

The protein components of saliva reflect the condition of the whole body as well as the salivary glands. The aim of this study is to characterize the gene expression profiles in each of the rat major salivary glands-the parotid, submandibular, and sublingual glands. Gene expression was analyzed using DNA microarrays, and observed differences in expression of representative genes were confirmed by quantitative, real-time polymerase chain reaction. Among the glands, the contribution to the high expression of genes encoding various proteins, specifically mucin 10, proline-rich glycoproteins, proline-rich protein 2, proline-rich proteoglycans, cystatin 10, amylase, deoxyribonuclease I, and von Ebner's gland protein, was significantly greater in the parotid gland than the other glands. The submandibular and sublingual glands had similar gene expression profiles that differed from profile of the parotid gland. For example, the genes encoding mucin 19 and ovomacroglobulin were highly expressed only in the submandibular and sublingual glands. In summary, we characterized gene expression in the rat major salivary glands and provided basic information on salivary gland marker proteins.

Oxidative stress, antioxidant status and lipid profile in the saliva of type 2 diabetics

BACKGROUND

The aim of this study was to assess the salivary content of lipid peroxidation and antioxidants in patients with type 2 diabetes.

METHOD

We studied 25 patients with type 2 diabetes and other 25 age- and sex-matched health control. To evaluate the oxidative status we measured the levels of malondialdehyde (MDA) in the saliva and serum of all participants. Lipid profile was also estimated through measuring total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and very low-density lipoprotein cholesterol (VLDL-C) levels. Antioxidant levels were also assessed through measuring the salivary and serum concentration of uric acid, superoxide dismutase and reduced glutathione (GSH).

RESULTS

The high concentration of lipid fractions in saliva usually follows that recorded in serum. Salivary MDA levels, a product of lipid peroxidation, were significantly increased among diabetics together with uric acid. However, GSH levels were similar to those of the control group.

CONCLUSION

Lipid peroxidation and antioxidant parameters assessed in saliva of diabetic patients may be of great importance in evaluating the disease activity and severity. The increase in lipid peroxidation and the tendency of antioxidants to rise in diabetes is probably due to an adaptive response to the pro-oxidant status of diabetes.

Evaluation of prooxidant-antioxidant balance in chronic heroin users in a single assay: an identification criterion for antioxidant supplementation

BACKGROUND

Opiate abuse has been linked to oxidative stress, through the separate evaluation of oxidants and antioxidants.

OBJECTIVES

To determine prooxidant-antioxidant balance (PAB) in chronic heroin users in a single assay, easily applied in a clinical setting. Specifically, to examine whether PAB values correlate with the duration of abuse or with the presence of anti-HCV antibodies.

METHODS

Sixty-four chronic heroin users - 34 cases and 30 controls - participated in this study. PAB was determined by an Enzyme-linked immunosorbent assay (ELISA) method, developed by members of the study group.

RESULTS

In heroin users, oxidative balance was disrupted in favor of prooxidants. There was no correlation of PAB values with the duration of abuse or with the presence of anti-Hepatitis C virus (HCV) antibodies.

CONCLUSIONS

Chronic heroin users can benefit from an antioxidant therapy, and the method currently presented can be used as an identification criterion.

Altered Salivary Redox Homeostasis in Patients with Systemic Sclerosis

Objective.

Oxidative stress has been implicated in the pathogenesis of systemic sclerosis (SSc). Our objective was to determine whether SSc is associated with altered redox homeostasis in human saliva.

Methods.

Study participants were 70 women with SSc and 120 female controls. 8-hydroxy-2’-deoxyguanosine (8-OHdG), 8-epi-prostaglandin F 2α (8-epi-PGF2α), and total protein carbonyls were assayed by ELISA to quantify oxidative damage to nucleic acids, lipids, and proteins, respectively, in whole nonstimulated saliva.

Results.

We observed a significantly positive association between salivary log protein carbonyls and SSc in a crude statistic (OR 9.06, p < 0.0001), and multivariable model adjusted for log 8-OHdG, log 8-epi-PGF2α, and antioxidant exposure (OR 9.26, p < 0.0001). No significant association was noted between SSc and salivary log 8-epi-PGF2α or log 8-OHdG.

Conclusion.

Salivary redox homeostasis is perturbed in patients with SSc and may inform on the pathophysiology and presence of the disease (biomarkers) and efficacy of therapeutic interventions.

Characteristics of inflammation common to both diabetes and periodontitis: are predictive diagnosis and targeted preventive measures possible?

Diabetes and periodontitis are chronic inflammatory disorders that contribute to each others' severity and worsen each others' prognosis. Studies have shown that patients with diabetes are at increased risk of developing periodontitis, and that diabetics with untreated periodontitis have more difficulty controlling serum glucose. Periodontal treatment that reduces gingival inflammation aids in the control of hyperglycemia. Periodontitis is accompanied by gingival bleeding and the production of an inflammatory exudate termed gingival crevicular fluid (GCF) that arises from the inflamed gingival tissues surrounding the teeth. GCF contains byproducts of connective tissue degradation, enzymes from host and bacterial cells, cytokines and other inflammatory mediators, and has been studied for screening blood glucose and for biomarkers of both diabetes and periodontitis. This review focuses on the inter-relationship between diabetes and periodontitis and the biomarkers common to both these diseases that may enable earlier detection, targeted preventive measures and individualized therapeutic intervention of these chronic conditions.

[Analysis of enzyme activity and the level of malondialdehyde in the saliva of children with gingivitis]

INTRODUCTION/AIM

By analysing activity of some of the enzymes normally present in the saliva and the level of malondialdehyde in gingivitis, it is possible to estimate the functional condition of parodontium, and the examined parametres can be considered as biochemical markers of its functional condition. The aim of this paper was to examine activity of alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, lactate dehydrogenase and the level of malondialdehyde in the saliva of children affected with gingivitis, as well as the values of the mentioned parametres in relation to the level of the inflammation of gingiva.

METHODS

The research included 120 children at the age of 12.2 with permanent dentition. Löe and Silness gingival index was used to estimate the condition of gingiva, based on which the childen were classified into four groups: the children with healthy gingiva (the control groups), the children with mild, moderate and severe inflammation of gingiva (the study group). Enzymes of the saliva were determined by the use of original tests and measured by the autoanalyser (Bio Systems A25, Spain). A modified method with tiobarbituric acid was used to determine malondialdehyde in nonstimulated mixed saliva.

RESULTS

The results of the examined enzyme activity and the level of malondialdehyde in the saliva of the study groups showed statistically considerably higher values for the level of malondialdehyde (p < 0.001), for the activity of aspartate aminotransferase and gamma glutamyl transferase (p < 0.01), as well as for alanine aminotransferase (p < 0.05) in comparison with the control group, whereas the activity of lactate dehydrogenase did not show a statistically significant increase. In relation to the level of the inflammation of gingiva, the results of the examination of the enzyme activity in the study groups showed statistically significantly higher values in the group with severe inflammation in comparison with those with mild, as well as the moderate inflamatiory, except for the gamma glutamyl transferase, and in the group with moderate inflammation compared to that with the mild one, except for alanine aminotransferase. The results of the examination of the level of malondialdehyde in the saliva of the study groups did not show a statistically significantly increase in relation to the level of the inflammation of gingiva.

CONCLUSION

There is a higher level of alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase and lactate dehydrogenase enzyme activity together with the higher level of malondialdehyde in the saliva of children with gingivitis in comparison with the activity of the same enzymes and the level of malondialdehyde in the saliva of children without gingivitis. The activity of the examined enzymes in the saliva of children with gingivitis increases in relation to the intensity of the pathological process, whereas the level of malondialdehyde shows no significant difference in relation to the level of the inflammation of gingiva.

Salivary antioxidants in patients with type 1 or 2 diabetes and inflammatory periodontal disease: a case-control study

BACKGROUND

The purpose of this study was to evaluate and compare salivary concentrations of reduced, oxidized glutathione, uric acid, ascorbic acid, and total antioxidant capacity in subjects with diabetes and systemically healthy subjects with inflammatory periodontal disease.

METHODS

Sixteen patients with type 1 diabetes mellitus (DM), 25 patients with type 2 DM, and 24 systemically healthy patients, all with inflammatory periodontal disease, were recruited. Whole-saliva samples were obtained, and full-mouth clinical periodontal measurements, including plaque index, probing depth, gingival recession, clinical attachment level, and bleeding on probing, were recorded at six sites per tooth. Saliva flow rate and salivary levels of reduced and oxidized glutathione, vitamin C, uric acid, and total antioxidant capacity were determined. Data were analyzed statistically by non-parametric tests.

RESULTS

The subjects with type 2 DM had fewer teeth and more sites with probing depths >4 mm than the patients with type 1 DM (both P <0.01). The mean salivary reduced-glutathione concentration was lower in patients with type 1 DM than in the other two groups (both P <0.05). No significant differences in the salivary concentrations of the other antioxidants measured were found among the groups (P >0.05). Oxidized glutathione levels in the patients with type 1 DM were significantly lower than in the systemically healthy group (P = 0.007). In both groups with diabetes, salivary reduced-glutathione levels correlated positively with probing depth, and total antioxidant capacity correlated with salivary flow rate (P <0.01).

CONCLUSION

The decrease in salivary reduced-glutathione levels in patients with type 1 DM may have a role in periodontal tissue destruction by predisposing tissues to oxidative stress.

Effect of sample storage on stability of salivary glutathione, lipid peroxidation levels, and tissue factor activity

Saliva samples are often required to be stored for longer periods of time either because of the project protocol or because of lack of funding for analysis. The effects of 6 months storage (fresh, 30, 60, 90 120, 150, and 180 d) on the stability of salivary reduced glutathione (GSH), lipid peroxidation (LPO) and 90 days of storage (fresh, 15, 30, 60, and 90 d) on the stability of salivary tissue factor (TF) activity and the stability of saliva imprint samples at -20 degrees C were evaluated in this study. Salivary GSH, malondialdehyde (MDA) levels as an index of LPO, and TF activities were determined using the methods of Beutler, Yagi, and Quick, respectively. Saliva imprint samples were stained with Giemsa and microscopically examined. Salivary GSH levels and TF activities decreased, whereas MDA levels increased significantly after 6 months of storage at -20 degrees C. Leucocyte, epithelium and bacterium cell counts did not significantly change at the end of 90 d of storage. Saliva samples may be stored up to 1 month at -20 degrees C for LPO assay. For cytological examinations, saliva samples may be stored for 90 d at -20 degrees C. Further studies are needed to determine the stability of salivary GSH, and salivary TF activity stored less than 30 days at -20 degrees C. On the other hand, if saliva samples are required to be stored, to avoid the changes because of different storage periods, we recommend that they must be stored under the same circumstances and in the same time period.