Evaluation of serum prolidase enzyme activity and oxidative stress in patients with tinnitus.

INTRODUCTION: Tinnitus is defined as the perception of sound in the head or in the head in the absence of external sounds. The cause of tinnitus is still unknown.

OBJECTIVE: We aimed to compare the serum levels of total oxidant status, total antioxidant status, serum prolidase enzyme activity and the oxidative stress index in patients with tinnitus to those of normal subjects.

METHODS: Twenty five patients with tinnitus (mean age 34.3) and 25 healthy controls (mean age 37.2) were included in the study.

RESULTS: Total oxidant status levels in the patient group were significantly higher than in the control group (p=0.037). The mean total oxidant status value was 2.54±0.95mmoL/L in the patient group, and 2.06±0.98mmoL/L in the control group. The mean oxidative stress index level was 0.22±0.10AU in the patient group, while it was 0.17±0.08AU in the control group. Oxidative stress index was significantly higher in the patient group (0.026). There was no significant difference between the groups in terms of total antioxidant status values (p=0.838). The mean serum prolidase enzyme activity level was 202.74±33.56U/L in the patient group and 175.46±42.68U/L in the control group. Serum prolidase enzyme activity levels in the patient group were significantly higher than in the control group (0.040).

CONCLUSION: We detected that the total oxidant status, oxidative stress index and serum prolidase enzyme activity levels were higher in patients with tinnitus when compared to the healthy controls. This finding suggests that oxidative stress index and serum prolidase enzyme activity may play a role in the etiopathogenesis of tinnitus.