Evaluation of serum prolidase enzyme activity and oxidative stress in patients with tinnitus / Avaliação da atividade da enzima sérica prolidase e do estresse oxidativo empacientes com zumbido

Abstract 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 ± 0.95 mmoL/L in the patient group, and 2.06 ± 0.98 mmoL/L in the control group. The mean oxidative stress index level was 0.22 ± 0.10 AU in the patient group, while it was 0.17 ± 0.08 AU 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 ± 33.56 U/L in the patient group and 175.46 ± 42.68 U/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.

Resumo Introdução O zumbido é definido como a percepção de um som na cabeça na ausência de sons externos. A causa do zumbido ainda é desconhecida. Objetivo Comparar os níveis séricos do estado oxidante total, estado antioxidante total, atividade da enzima prolidase sérica e o índice de estresse oxidativo em pacientes com zumbido e em indivíduos normais. Método Foram incluídos no estudo 25 pacientes com zumbido (média de 34,3 anos) e 25 controles saudáveis (média de 37,2 anos). Resultados Os níveis do estado oxidante total no grupo de pacientes foram significantemente maiores do que no grupo controle (p = 0,037). O valor médio do estado oxidante total foi de 2,54 ± 0,95 mmoL/L no grupo de pacientes e de 2,06 ± 0,98 mmoL/L no grupo controle. O nível médio de índice de estresse oxidativo foi de 0,22 ± 0,10 AU no grupo de pacientes, enquanto no grupo controle foi de 0,17 ± 0,08 AU. O índice de estresse oxidativo foi significantemente maior no grupo de pacientes (0,026). Não houve diferença significante entre os grupos em relação aos valores do estado antioxidante total (p = 0,838). O nível médio de atividade da enzima prolidase sérica foi de 202,74 ± 33,56 U/L no grupo de pacientes e de 175,46 ± 42,68 U/L no grupo controle. Os níveis de atividade da enzima prolidase sérica no grupo de pacientes foram significantemente maiores do que no grupo controle (0,040). Conclusão Detectamos que os níveis de estado oxidante total, índice de estresse oxidativo e atividade da enzima prolidase sérica foram maiores nos pacientes com zumbido quando comparados aos controles saudáveis. Esse achado sugere que o índice de estresse oxidativo e a atividade da enzima prolidase sérica podem desempenhar um papel na etiopatogenia do zumbido.

Serum Prolidase Activity in Metabolic Syndrome

Metabolic syndrome (Mets) is defined as the existence of central obesity, insulin resistance, glucose intolerance, hypertension and dyslipidemia. Prolidase, a member of Matrix metalloproteinases (MMPs), plays an important role in collagen metabolism and extracellular matrix remodelling. Altered Matrix Metalloproteinase (MMPs) is the important factor in the pathogenesis of MetS. Methods: In this study 50 cases with metabolic syndrome diagnosed based on the Adult Treatment panel III ( ATP III ) criteria of the National Cholesterol & Education program (NCEP) and 50 age, sex matched healthy individuals were taken as control. Serum prolidase was estimated by ELISA, fasting plasma glucose, lipid profile, urea & creatinine were estimated by standard methods. Results: The prolidase levels was significantly higher in metabolic syndrome group (41.49±6.59) compared to control group (28.86±3.39) with a p value < 0.05. Statistical analysis were done by SPSS20 software. Conclusion: The serum prolidase values showed positive correlation with waist circumference, SBP, DBP, TG, LDL-C & negative correlation with HDL-C.

Decreased Prolidase Activity in Patients with Posttraumatic Stress Disorder

OBJECTIVE: Many neurochemical systems have been implicated in the development of Posttraumatic Stress Disorder (PTSD). The prolidase enzyme is a cytosolic exopeptidase that detaches proline or hydroxyproline from the carboxyl terminal position of dipeptides. Prolidase has important biological effects, and to date, its role in the etiology of PTSD has not been studied. In the present study, we aimed to evaluate prolidase activity in patients with PTSD. METHODS: The study group consisted of patients who were diagnosed with PTSD after the earthquake that occurred in the province of Van in Turkey in 2011 (n=25); the first control group consisted of patients who experienced the earthquake but did not show PTSD symptoms (n=26) and the second control group consisted of patients who have never been exposed to a traumatic event (n=25). Prolidase activities in the patients and the control groups were determined by the ELISA method using commercial kits. RESULTS: Prolidase activity in the patient group was significantly lower when compared to the control groups. Prolidase activity was also significantly lower in the traumatized healthy subjects compared to the other healthy group (p<0.01). CONCLUSION: The findings of the present study suggest that the decrease in prolidase activity may have neuroprotective effects in patients with PTSD.

Acute effect of phosphodiesterase type 5 inhibitor on serum oxidative status and prolidase activities in men with erectile dysfunction

OBJECTIVES: To investigate the acute effect of phosphodiesterase type 5 (PDE5) inhibitor on erectile dysfunction by evaluating serum oxidative status and prolidase activity. METHODS: Serum samples of 36 patients with erectile dysfunction and 30 control cases were analyzed for total antioxidant status, total oxidant status, and prolidase activity, before and after the administration of tadalafil citrate. RESULTS: Before and after tadalafil citrate administration, serum total antioxidant status, total oxidant status, and prolidase were 1.1+0.0 vs. 1.6 + 0.0 umol H2O2 Eq/L, 10.3+1.1 vs. 6.9 + 1.2 umol H2O2 Eq/L, and 236.4+19.5 vs. 228.2 + 19.2 U/L, respectively (p<0.0001 for all). CONCLUSIONS: Evaluation of serum oxidative status and prolidase activity confirmed the beneficial acute effects of PDE5 inhibitor in patients with erectile dysfunction.

Diagnostic significance of plasma prolidase activity in chronic liver diseases / 第三军医大学学报

The activity of plasma prolidase(PLD)was determined in patients with various chronic liver diseases.It was found that the activity of plasma PLD was increased significantly in 45 patients with cirrhosis and 31 patients with chronic active hepatitis.The plasma level of PLD was not correlated with the serum level of ALP.Plasma PLD was negatively correlated with serum albumin and positively correlated with serum gammablobulin.These findings suggest that the determination of the activity of plasma prolidase may be helpful in the diagnosis of chronic liver diseases.