The relationships among the levels of oxidative and antioxidative parameters, FEV1 and prolidase activity in COPD

Prolidase could be considered a sign of inflammation associated with cigarette smoking

Objectives

Smoking causes inflammation, thickening, and narrowing of the airways. This inflammatory process is a reaction to free radicals and oxidants. Smoking affects collagen metabolism and tissue remodeling. Prolidase enzyme hydrolyzes iminodipeptides with hydroxyproline and C terminal proline. It plays a crucial role in the metabolism of collagen and the remodeling of the matrix. The present study aims to reveal the association of prolidase with inflammation caused by smoking and to compare serum prolidase levels with oxidative-antioxidative status in healthy individuals.

Methods

A total of 76 participants (38 smokers and 38 nonsmokers) were involved in the present study. Serum cotinine levels were measured to show the exposure to nicotine in tobacco smoke by using the competitive inhibition enzyme immunoassay method. Serum prolidase, total oxidant status (TOS), and total antioxidant status (TAS) were determined by the enzyme-linked immunosorbent (ELISA) method, respectively. The correlation between smoking, serum prolidase levels, TOS, and TAS was investigated.

Results

TAS and serum prolidase levels of smokers were considerably lower than those in non-smokers (p < 0.001, p = 0.012 respectively). However, no differences were observed in TOS between the two groups. There was no statistically significant correlation between serum prolidase levels, TAS, and TOS. Moreover, no relationship was observed between respiratory function parameters and serum prolidase levels.

Conclusion

To the best of our knowledge, the present study is the first study to demonstrate the role of prolidase in smoking-related inflammation. The results achieved in the present study suggest that smoking creates an imbalance in the oxidant-antioxidant activity. Smoking decreases prolidase levels, leading to decreased collagen turnover. Chronic pulmonary disease might be related to this decrease in collagen turnover.

Stabil Kronik Obtrüktif Akciğer Hastalığı Hastalarında Serum Prolidaz ve Karbonik Anhidraz III Düzeylerinin Klinik Önemi

GİRİŞ: Kronik obstrüktif akciğer hastalığı (KOAH), geri dönüşümsüz hava yolu akış kısıtlaması ve kronik hava yolu iltihabı ile karakterize bir hastalıktır. Kollajen yıkımının bir göstergesi olan serum prolidaz enzimi ile asit-baz regülasyonunda önemli işlevi olan karbonik anhidraz (CA) III enziminin KOAH'lı hastalarda klinik önemini araştırmayı amaçladık. GEREÇ VE YÖNTEM: Bu çalışmaya 56 stabil KOAH'lı hasta ile sigara öyküsü ve ek hastalığı olmayan 32 sağlıklı olgu dahil edildi. Her iki grup arasında serum CA III ve prolidaz enzim düzeyleri karşılaştırıldı. BULGULAR: Prolidaz enzim düzeyleri açısından iki grup arasında istatistiksel fark bulunmadı (p=0.831). KOAH grubunda CA III düzeylerinde istatistiksel olarak anlamlı bir artış vardı (p=0.001). KOAH hastalarında CA III enzimi düzeyi ile kanda kısmi karbondioksit basıcı (pCO2) arasında orta derecede pozitif, kanda kısmi oksijen basıncı (pO2) arasında ise negatif korelasyon vardı (r:0.302, p&lt;0.025; r:-0.314, p:0.02). SONUÇLAR: CA III ile KOAH arasında önemli bir klinik ilişki olduğunu ve bu nedenle CA III'ün KOAH takibinde aday bir biyobelirteç olabileceğini düşünüyoruz.

Relationship between serum sialic acid levels and prolidase activity with airflow obstruction in patients with COPD

ABSTRACT

Our aim in this study was to evaluate the prognostic significance of sialic acid (SA) and prolidase activity and to evaluate the association between airflow obstruction severity and these parameters in chronic obstructive pulmonary disease (COPD) patients.Ninety-four patients (84 M, 10 F) and 34 healthy subjects (19 M, 15 F) were included into the study. COPD staging was performed to COPD patients according to new global initiative for chronic obstructive lung disease criteria which includes pulmonary function tests, symptoms and hospitalization; COPD patients were divided into 4 subgroups as group A (n = 25), group B (n = 19), group C (n = 20), and group D (n = 28).SA and C-reactive protein levels were significantly higher than the control group in all COPD groups. SA levels were significantly higher in group B patients than the control and group A. Prolidase activity was significantly lower than control group in total COPD groups (P < .05). There was a weak negative correlation between SA and forced vital capacity (r = -0.217, P = .038) and forced expiratory volume in 1 second (FEV1) (r = -0.210, P = .045), whereas weak positive correlation was present between SA and Creactive protein (r = 0.247, P = .018) in all patient groups. There was weak positive correlation between prolidase and FEV1 (r = 0.222, P = .033) and FEV1/forced vital capacity (r = 0.230, P = .027).Our study shows that systemic inflammation, prolidase activity, and SA levels in stable COPD patients are associated with airflow obstruction severity. In addition to the prolidase activity; SA levels might be associated with inflammation.

Reactive Oxygen Species and Antioxidative Defense in Chronic Obstructive Pulmonary Disease

The respiratory system is continuously exposed to endogenous and exogenous oxidants. Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation of the airways, leading to the destruction of lung parenchyma (emphysema) and declining pulmonary function. It is increasingly obvious that reactive oxygen species (ROS) and reactive nitrogen species (RNS) contribute to the progression and amplification of the inflammatory responses related to this disease. First, we described the association between cigarette smoking, the most representative exogenous oxidant, and COPD and then presented the multiple pathophysiological aspects of ROS and antioxidative defense systems in the development and progression of COPD. Second, the relationship between nitric oxide system (endothelial) dysfunction and oxidative stress has been discussed. Third, we have provided data on the use of these biomarkers in the pathogenetic mechanisms involved in COPD and its progression and presented an overview of oxidative stress biomarkers having clinical applications in respiratory medicine, including those in exhaled breath, as per recent observations. Finally, we explained the findings of recent clinical and experimental studies evaluating the efficacy of antioxidative interventions for COPD. Future breakthroughs in antioxidative therapy may provide a promising therapeutic strategy for the prevention and treatment of COPD.

Total Antioxidant Status in Stable Chronic Obstructive Pulmonary Disease

Objective

This study evaluates the total antioxidant status (TAS) in plasma of stable chronic obstructive pulmonary disease (COPD) patients. Earlier studies of their relationship showed inconsistent findings.

Patients and Methods

We compared TAS between 90 COPD patients and 30 age- and sex-matched controls (mean age 67 ± 7.9, 87 males and 33 females) according to airway obstruction severity, gender, smoking status (current/ former/ non-smoker), smoking-dose, the number of exacerbations in the previous year, nutritional status and hypercapnia.

Results

There were no differences in pack-years between COPD and controls, neither in COPD groups. The median time from the last exacerbation was 5 months (interquartile range 3-8.3). TAS was significant higher in COPD than controls (1.68 [1.55-1.80] versus 1.59 [1.54-1.68], respectively; P = 0.03). TAS was significantly higher in COPD men than women (1.7 [1.6-1.8] versus 1.57 [1.5-1.7], respectively; P = 0.001). In COPD groups, there were no significant differences between the severity of airway obstruction and TAS. We found significant positive correlation between pack-years and TAS in all participants (Rho = 0.429, P = 0.004) and COPD patients (Rho = 0.359, P = 0.02), but not in controls. TAS was a significant predictor of COPD (β = 3.26; P = 0.04; OR = 26.01; 95% CI: 1.20 to 570.8). We failed to find significant differences between TAS and smoking status, frequency of exacerbations in the previous year, nutritional status and hypercapnia.

Conclusion

TAS was a significant predictor of COPD. TAS was a significantly higher in stable COPD than controls, higher in COPD men than women, but there was no significant correlation between TAS and the airway obstruction severity. Our results suggest that it could be appropriate to include the time from the last exacerbation in the oxidant-antioxidant balance analysis of COPD patients.

Reliability and Usefulness of Different Biomarkers of Oxidative Stress in Chronic Obstructive Pulmonary Disease

Introduction

Chronic obstructive pulmonary disease (COPD) is a progressive disease characterized by airflow limitation that is not fully reversible after inhaled bronchodilator use associated with an abnormal inflammatory condition. The biggest risk factor for COPD is cigarette smoking. The exposure to noxious chemicals contained within tobacco smoke is known to cause airway epithelial injury through oxidative stress, which in turn has the ability to elicit an inflammatory response. In fact, the disruption of the delicate balance between oxidant and antioxidant defenses leads to an oxidative burden that has long been held responsible to play a pivotal role in the pathogenesis of COPD. There are currently several biomarkers of oxidative stress in COPD that have been evaluated in a variety of biological samples. The aim of this review is to identify the best studied molecules by summarizing the key literature findings, thus shedding some light on the subject.

Methods

We searched for relevant case-control studies examining oxidative stress biomarkers in stable COPD, taking into account the analytical method of detection as an influence factor.

Results

Many oxidative stress biomarkers have been evaluated in several biological matrices, mostly in the blood. Some of them consistently differ between the cases and controls even when allowing different analytical methods of detection.

Conclusions

The present review provides an overview of the oxidative stress biomarkers that have been evaluated in patients with COPD, bringing focus on those molecules whose reliability has been confirmed by the use of different analytical methods.

Comparison of oxidant/antioxidant balance in COPD and non-COPD smokers

BACKGROUND/AIM

Oxidative stress plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). Smoking is the leading source of oxidants in lungs. However, it is currently unknown why some individuals are more resistant to the detrimental effects of smoking and do not develop COPD. The aim in this study is to measure and compare the oxidant/antioxidant balance between in non-COPD individuals who smoke and COPD patients who smoke.

MATERIALS AND METHODS

Included in the study were 137 patients with COPD and 102 healthy individuals. Participants were divided into groups as COPD patients (former and current smokers), non-COPD individuals who smoke and non-smokers healthy persons. In the following stage, the total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) levels were measured in serum for all participants.

RESULTS

In the current-smoker COPD group, the level of oxidant status were significantly higher than the former-smoker COPD group (p < 0.001). Similarly, oxidant levels were significantly high in current-smoker healthy group than never smoker healthy group. According to these results TOS was associated with especially smoking status rather than COPD. Antioxidant status were similar between former-smoker COPD group and current-smoker COPD group. The antioxidant levels were found significantly low in current-smoker COPD patients, compared to the current-smoker non-COPD individuals (p = 0.007). Nevertheless, no significant difference was found in OSI levels between two groups. Briefly, high TOS and OSI values were correlated with only smoking, independently from COPD.

CONCLUSION

It was concluded that there are complex pathogenetic mechanisms, including genetic and individual variations other than oxidant/antioxidant balance, involved in the development of smoking-related COPD. TOS and OSI values are not predictive parameters for the development of COPD, but high level of TAS in non-COPD smokers is promising for future studies.

Circulating biomarkers of oxidative stress in chronic obstructive pulmonary disease: a systematic review

Chronic obstructive pulmonary disease (COPD) is a progressive condition characterized by airflow limitation associated with an abnormal inflammatory response of the lungs to noxious particles and gases, caused primarily by cigarette smoking. Increased oxidative burden plays an important role in the pathogenesis of COPD. There is a delicate balance between the toxicity of oxidants and the protective function of the intracellular and extracellular antioxidant defense systems, which is critically important for the maintenance of normal pulmonary functions. Several biomarkers of oxidative stress are available and have been evaluated in COPD. In this review, we summarize the main literature findings about circulating oxidative stress biomarkers, grouped according to their method of detection, measured in COPD subjects.

Serum prolidase activity and oxidative-antioxidative status in patients with developmental dysplasia of the hip and its relationship with radiographic severity

BACKGROUND

We aimed to investigate serum prolidase activity and to investigate its association with oxidative-antioxidative status in patients with developmental dysplasia of the hip (DDH).

METHODS

Oxidative status parameters, including lipid hydroperoxide (LOOH), total oxidant status (TOS), and the oxidative stress index (OSI), and antioxidative status parameters, free sulfhydryl groups (Total -SH), and total antioxidative capacity (TAC), as well as serum prolidase activity were assessed in patients with DDH (n = 93), and in healthy controls (n = 82). The severity of dysplasia was evaluated according to the Tonnis grading system.

RESULTS

Serum prolidase activity and the oxidant parameters (LOOH, TOS, and OSI) were significantly higher and the antioxidant parameters (Total -SH and TAC) were significantly lower in patients with DDH compared to the controls (P < 0.005 for all). Serum prolidase activity was positively correlated with the Tonnis grade of DDH and LOOH, TOS, and OSI levels (P < 0.001 for all), but inversely correlated with total -SH and TAC levels (P < 0.001 for all).

CONCLUSION

Increased levels of serum prolidase activity, LOOH, TOS, and OSI, and decreased levels of total -SH and TAC, may be associated with DDH, and these parameters may be useful adjunctive tools to assess the severity of DDH.