The mRNA expression of genes encoding selected antioxidant enzymes and thioredoxin, and the concentrations of their protein products in gingival crevicular fluid and saliva during periodontitis.

BACKGROUND: The activity of antioxidant enzymes in periodontitis is reduced, but results vary between studies and are subject to bias. In turn, the expression of genes encoding antioxidant factors has not been examined yet. OBJECTIVES: This is the first study to evaluate the expression of genes encoding superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1) and thioredoxin 1 (TXN1) in the saliva and gingival tissue of patients with periodontitis. The activity of the antioxidant enzyme protein products in the unstimulated and stimulated saliva and the gingival crevicular fluid (GCF) of patients with periodontitis was also investigated. MATERIAL AND METHODS: The prospective study involved 65 patients with periodontitis, who were divided into groups depending on the disease stage, and a control group of 31 ageand gender-matched healthy patients. RESULTS: We demonstrated that the expression of genes encoding GPX1 and TXN1 in saliva was significantly higher, and the expression of genes encoding SOD1, GPX1 and TXN1 in the gingival tissue was significantly lower in periodontitis patients as compared to the control group. We noted a lower activity of GPX1 in unstimulated saliva, of SOD1 in stimulated saliva and of both antioxidant enzymes in GCF in patients with periodontitis. CONCLUSIONS: The GPX1 transcriptome and its activity in the salivary and GCF proteome appear to be dependent on the oxidative stress related to the destructive inflammatory changes in periodontitis.

Enzymatic antioxidants activity in gingival crevicular fluid and saliva in advanced periodontitis.

AIM: Enzymatic antioxidants are the primary line of defense against oxidative and nitrosative stress. However, their involvement in the progression of periodontitis is still not well understood. The study aimed to determine the activity of enzymatic antioxidants in the gingival crevicular fluid (GCF) and saliva of patients with periodontitis. MATERIALS AND METHODS: The study group of 56 patients with periodontitis (stage III and IV) and 28 healthy controls were involved. The modified plaque index, probing depth, the clinical attachment level, the percentage of sites with bleeding on probing, papilla bleeding index, and maximum value of tooth mobility (Periotest®) were tested. Saliva (stimulated and non-stimulated) and GCF were collected from the participants, and activity of peroxidase, catalase, superoxide dismutase, and glutathione reductase were determined colorimetrically. RESULTS: Lower activity of peroxidase (p < 0.0001), catalase (p < 0.0001), superoxide dismutase (p = 0.0188), and glutathione reductase (p < 0.0001) was noted in non-stimulated saliva of patients with periodontitis compared to healthy subjects. Peroxidase (p < 0.0001), catalase (p < 0.0001) and superoxide dismutase (p < 0.0001) showed lower activity in stimulated saliva of patients with periodontitis compared to healthy subjects. The peroxidase (p < 0.0029), catalase (p < 0.0001), and glutathione reductase (p = 0.0028) activity in GCF of stage III + IV were significantly higher compared to healthy controls. Superoxide dismutase (p < 0.0001) showed lower activity in GCF of patients with periodontitis. CONCLUSIONS: The demonstrated decrease in activity of all analyzed enzymatic antioxidants in non-stimulated saliva may result from long-lasting periodontitis and exhaustion of the safeguard mechanism against reactive oxygen species.

Gingival fluid and saliva concentrations of selected non-enzymatic antioxidants in periodontitis.

BACKGROUND: Due to their low specificity, non-enzymatic antioxidants play a significant role in the protection of organisms against free radicals. They are normally sourced from the diet, and independently react with oxidizing molecules and their products. OBJECTIVES: The study aimed to determine the concentrations of selected non-enzymatic antioxidants (uric acid (UA), reduced glutathione (GSH) and polyphenols) in the gingival fluid and saliva of patients diagnosed with periodontitis according to the current criteria. MATERIAL AND METHODS: This prospective case-control study included 50 patients with periodontitis, who were divided into 2 groups depending on disease severity, along with 25 healthy controls. Unstimulated saliva, stimulated saliva and gingival crevicular fluid (GCF) were collected from all subjects, and nonenzymatic antioxidant concentrations were determined. RESULTS: Significantly lower concentrations of all tested non-enzymatic antioxidants were observed in the gingival fluid as well as in the unstimulated and stimulated saliva of patients with periodontitis (p < 0.05). Moreover, the concentration of GSH was a parameter that differentiated the various degrees of periodontitis (p < 0.05). A significantly lower concentration of GSH was found in the stimulated saliva of patients with moderate progression as compared to those with fast progression of the disease (p < 0.05). CONCLUSIONS: The continuation of research on the GSH concentrations in the gingival fluid and saliva may be useful in the context of biomarkers for periodontitis progression.

Total Oxidant and Antioxidant Capacity of Gingival Crevicular Fluid and Saliva in Patients with Periodontitis: Review and Clinical Study.

Periodontitis is inextricably linked to oxidative-reductive (redox) imbalance. However, little is still known about the resultant ability to scavenge oxygen free radicals in saliva and gingival crevicular fluid in patients with periodontitis. The multitude of enzymatic and non-enzymatic antioxidants and their synergistic effects cause an interest in the evaluation of the total antioxidative capacity. Thus, our study aimed to evaluate the total oxidative and antioxidative activity of gingival crevicular fluid and saliva in the periodontitis, as well as to relate these biomarkers to clinical indices of periodontopathy. Additionally, by calculating the oxidative stress index (OSI), the intensity of redox disturbances was also evaluated. Fifty-eight periodontitis patients were included in the study and divided into two subgroups depending on the severity of the disease. In the non-stimulated/stimulated saliva as well as a gingival crevicular fluid of the study group, we found significantly higher OSI and total oxidant status (TOS) as well as lower total antioxidant capacity (TAC). However, the ability to reduce iron ions (FRAP) was significantly lower only in stimulated and non-stimulated saliva of patients with periodontitis. The examined parameters correlated with the periodontium's clinical condition, which indicates the exacerbation of the inflammatory process. However, TAC, TOS, OSI, and FRAP did not differentiate individual stages of periodontitis.

Nitrosative Stress Biomarkers in the Non-Stimulated and Stimulated Saliva, as well as Gingival Crevicular Fluid of Patients with Periodontitis: Review and Clinical Study.

Diagnosis of periodontopathy is complex and includes defining the cause, type, stage, and grade of periodontitis. Therefore, alternative diagnostic methods are sought to indicate the progression of inflammation or to determine the effectiveness of therapy. Gingival crevicular fluid (GCF) biomarkers can be particularly useful because they most likely reflect the disease process of the periodontal tissues. However, the difficulty of collecting GCF for testing is the reason for the limited use in diagnostics. Because periodontitis is the primary source of nitrogen free radicals in the oral cavity, the aim of the study was to evaluate the biomarkers of nitrosative stress (nitric oxide, peroxynitrite, and S-nitrosothiols) in GCF, non-stimulated and stimulated saliva of 90 patients with periodontitis. The study group was divided into two subgroups, depending on the stage of the disease severity. We showed a significantly higher concentration of all assessed biomarkers in the non-stimulated and stimulated saliva of patients with periodontitis. However, significant changes in GCF has been shown only for peroxynitrite. The studied biomarkers did not correlate with clinical periodontal status, which probably results from their short-duration activity and the impact on a few factors in the oral cavity. Saliva and gingival fluid are not very useful in the differential diagnosis of periodontitis.

Activity of enzymatic antioxidants in periodontitis: A systematic overview of the literature.

Periodontitis is initiated by a bacterial infection and an abnormal immune response of the host resulting in the formation of dysbiotic subgingival biofilm and the progressive destruction of the attachment apparatus of the teeth. It is believed that disturbances in the local and/or general indicators of oxidative stress are one of the mechanisms in the etiopathogenesis of periodontitis. Organisms using oxygen in their metabolic processes are equipped with mechanisms that protect against the activity of oxygen-free radicals. They are commonly referred to as 'the antioxidative barrier of the system'. The main enzymatic antioxidants which have been widely studied in the gingival fluid, saliva and blood serum of patients with periodontitis are superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT). The aim of this systematic overview of the literature was to present the current research on the activity of these antioxidant enzymes in the gingival fluid, saliva and blood serum of patients with periodontitis. Findings on the activity of these enzymes in the gingival tissue, gingival fluid, saliva, and blood serum in the course of the types of periodontitis that have been classified so far (chronic or aggressive) are quite disparate. Their activity in the gingival tissue was usually elevated, whereas in the saliva it was reduced. These differences may have resulted from the different methods of biochemically assessing their activity, and may have not reflected the stage and/or the risk of progression of periodontitis.