Hydrogen peroxide

Inflammatory cells such as macrophages and neutrophils released reactive oxygen species (ROS) like hydrogen peroxide (H2O2) and play a role in the pathophysiology of childhood asthma. Elevated levels of hydrogen peroxide have been found in a number of respiratory disorders, including cystic fibrosis, chronic obstructive pulmonary disorder and asthma. Thus, hydrogen peroxide is considered to be a possible biomarker of airway inflammation. ( Respir Res.(2012), J Chromatogr B AnalytTechnol Biomed Life Sci.(2004)). Since the bronchoalveolar extracellular lining fluid contains a large number of mediators of airway inflammation and oxidative damage, exhaled breath condensate (EBC) was frequently used todetect the hydrogen peroxideconcentration (Br J Dermatol. (2012)). Hydrogen peroxide was identified through diagnostic studies such as 'study name, citations' and 'another study name, citations'. However, it is a proposed prognostic lipid mediator that can be measured to predict an individual's associative risk of developing the following conditions or diseases: asthma, chronic obstructive pulmonary disease, pneumonectomy, bronchiectasis, breast neoplasms, atopic dermatitis, fever, obstructive lung diseases, obstructive sleep apnea, rhinitis and sleep apnea syndromes. The commercial kit (e.g. Amplex Red Hydrogen Peroxide Assay Kit) for H2O2 measured in EBC (exhaled breath condensate) was available. Spectrophometer is the most commonly method for H2O2 detection H2O2 concentrations were also measured by fluorescence and enzyme immunoassay (EIA). Although there are numbers of studies enrolled children, adult patients and healthy volunteers, the patients numbers in each studies was very limited (Inflammation. (2007), Sleep Breath. (2012) and J Cancer Res Clin Oncol. (2010)). Description of disease(s) related to hydrogen peroxide:

Disease summary

Asthma

The pH and levels of CRP, H2O2 and nitrate were correlated with asthma severity and significantly higher in the mild persistent group than that in the other groups. (Respirology.(2008))

Chronic obstructive pulmonary disease (COPD)

The H2O2 levels were elevated and pH was lower in both asthma and COPD compared with control subjects (COPD.(2014)). Pneumonectomy: In both exhaled breath condensate and blood, H2O2 levels significantly and directly correlated with the duration of one-lung ventilation immediately before resuming two-lung ventilation and immediately after resuming two-lung ventilation. (Eur J Cardiothorac Surg. (2015)).

Bronchiectasis

H2O2 is elevated in exhaled air condensate of patients with bronchiectasis and is correlated with disease severity (Am J Respir Crit Care Med. (1998)). Breast Neoplasms: The H2O2 concentration was significantly correlated and increased in cases with nodal metastases. Patients with localized breast malignancy was associated with H2O2 increment in EBC in and also related with its clinical severity (J Cancer Res Clin Oncol. (2010)).

Atopic Dermatitis (AD)

Patients with AD were analysis their inflammatory mediators in the EBC and they found that exhaled H2O2 concentrations were significantly higher in controls compared with patients affected by AD (Br J Dermatol. (2012)). Obstructive Lung Diseases: H202 levels in EBC was significantly higher in obstructive lung diseases group. The levels of H202 in EBC was also showed a positive and significant correlation with % eosinophils in IS (Inflammation. (2007)).

Renal Dialysis (RD)

Chronic RD patients exhale more H2O2 than healthy subjects at baseline. Although no change of breath H2O2 concentration was observed during RD, as H2O2 easily diffuses through the dialyser membrane, EBC H2O2 concentration was 22 times higher in Renal Dialysis patients than in controls (Nephrol Dial Transplant. (2004)).

Obstructive Sleep Apnea

H2O2 was shown to be an indirect index of altered redox status in the respiratory tract, since children with moderate-to-severe OSA have increased H2O2 levels in morning EBC (Sleep Breath. (2012)).

Summary of extracted biomedical information

Hydrogen peroxide is associated with abnormalities such as Oxygen toxicity. The involved biomedical functions are known as Oxidation, Oxidants, Respiration, enzyme activity and Evolution. Hydrogen peroxide is associated with Hydroxyl Radical, Ozone, Superoxides, Toluene and manganese oxide.