Salivary Antioxidants and Oxidative Stress in Psoriatic Patients: Can Salivary Total Oxidant Status and Oxidative Status Index Be a Plaque Psoriasis Biomarker?

Abstract

The aim of our research was to evaluate redox balance parameters and biomarkers of oxidative stress (OS) in nonstimulated and stimulated saliva as well as the blood of patients with plaque psoriasis compared to healthy controls. The study involved 40 patients with plaque psoriasis and 40 generally healthy subjects matched by age and gender to the study group patients. We assayed the concentration/activity of antioxidant enzymes: salivary peroxidase (Px), catalase (CAT), and superoxide dismutase (SOD) measured in unstimulated saliva (NWS), stimulated saliva (SWS), and erythrocytes. In plasma as well as NWS and SWS, we measured the concentration/activity of reduced glutathione (GSH), total antioxidant potential (TAC), total oxidative status (TOS), oxidative stress index (OSI), and markers of oxidative modification of proteins: advanced glycation end products (AGE), advanced oxidation protein products (AOPP), and lipid oxidation products: malondialdehyde (MDA) and total lipid hydroperoxide (LOOH). In NWS and SWS, we also evaluated the rate of reactive oxygen species (ROS) production. The concentration of Px, CAT, and SOD was significantly higher in NWS of patients with plaque psoriasis vs. healthy subjects. In SWS of psoriatic patients, we observed considerably higher concentration of Px and CAT, and in erythrocytes of patients with plaque psoriasis, the concentration of GPx and CAT was significantly higher compared to that in the controls. The levels of AOPP, AGE, MDA, and LOOH were considerably higher in NWS, SWS, and plasma of the study group compared to the controls. The concentration of total protein and salivary amylase was significantly lower in NWS and SWS of psoriatic patients compared to the healthy control. In the course of plaque psoriasis, we observed redox imbalances with prevalence of oxidation reactions. Mechanisms involved in the synthesis/secretion of proteins and activity of amylase were depressed in both glands of psoriatic patients; however, they were more inhibited in the parotid gland compared to the submandibular gland. TOS concentration and OSI value in NWS and SWS may serve as diagnostic biomarkers of plaque psoriasis.

A Case-Control Study of Salivary Redox Homeostasis in Hypertensive Children. Can Salivary Uric Acid be a Marker of Hypertension?

“…Indeed, oxidative stress is a key pathological factor responsible for hyposalivation in the course of many systemic diseases. Its role in salivary hypofunction has been confirmed in patients with diabetes, insulin resistance, chronic kidney disease, psoriasis, and cancer [20,[68][69][70].…”

A Longitudinal Study of the Antioxidant Barrier and Oxidative Stress in Morbidly Obese Patients after Bariatric Surgery. Does the Metabolic Syndrome Affect the Redox Homeostasis of Obese People?

“…Recently, there has been a growing interest in the use of redox biomarkers in the diagnosis of various systemic diseases [19,36,[63][64][65][66][67][68][69]. This is not surprising because oxidative stress plays a key role not only in the pathogenesis of neurodegenerative diseases/cancers but also many metabolic diseases such as insulin resistance, hypertension, diabetes and metabolic syndrome [40].…”

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

“…Immediately after collecting, samples were centrifuged (5000× g, 20 min, 4 • C). The supernatant fluid was preserved for the study, to which an antioxidant (10 µL of 0.5 M butylated hydroxytoluene per 1 mL of saliva) was added [15]. Such samples were frozen at −80 • C.…”

“…The supernatant fluid was preserved for testing. An antioxidant (10 µL of 0.5 M butylated hydroxytoluene per 1 mL of gingival crevicular fluid) was added to the samples containing GCF and mixed with a vortex mixer [15]. The gingival crevicular fluid was used for all markings on the same day.…”