Evaluation of eicosanoids in nasal lavage as biomarkers of inflammation in patients with allergic rhinitis

8-iso-prostaglandin E2 induces nasal obstruction via thromboxane receptor in murine model of allergic rhinitis

Thromboxane receptor (TP) mediates nasal obstruction, a typical symptom of allergic rhinitis. Since it has been reported that several types of eicosanoids, such as non-enzymatic oxidation product of arachidonic acid isoprostane, act as a TP ligand, there is a possibility that some other eicosanoids contribute to the TP-mediated nasal obstruction. The aim of this study is to investigate the mechanisms of TP-mediated nasal obstruction. Intranasal challenges of ovalbumin (OVA) induced nasal obstruction in mice. Pharmacological blockade of TP receptor but not thromboxane A₂ synthase inhibited OVA-induced nasal obstruction. Simultaneous analysis of eicosanoids in nasal lavage fluid and the responses in trans-endothelial resistance suggested that 8-iso-prostaglandin E₂ (PGE₂ ) can be a candidate for TP ligand. Intranasal challenge of 8-iso-PGE₂ induced vascular hyperpermeability and nasal obstruction in TP receptor-dependent manner. Wholemount immunostaining of nasal septum mucosa revealed that 8-iso-PGE₂ increased plasma leakage accompanied by distention of venous sinusoids. This study shows that 8-iso-PGE₂ is a contributor in TP-mediated nasal obstruction in mice.

Functional significance of 8-isoprostanes in sinonasal disease and asthma

BACKGROUND

The purpose of this study was to investigate how 8-isoprostanes, used as a marker of airway oxidative stress, were related to sinus disease and asthma.

METHODS

We analyzed samples and data from two separate studies, one investigating sinonasal disease in asthma, the other investigating the effect of BMI on airway disease. We measured airway (nasal lavage) 8-isoprostanes and investigated the relationship with measures of sinus and asthma symptoms, asthma control and lung function.

RESULTS

The study of people with sinonasal disease and poorly controlled asthma included 48 obese, 31 overweight and 23 lean participants. In multivariate analysis, nasal lavage 8-isoprostane levels increased with increasing BMI (p < 0.01), and were higher in Caucasian than African American participants (p = 0.01). Sinus symptoms were inversely related to nasal 8-isoprostanes (p = 0.02) independent of BMI and Race. In the study investigating the effect of BMI on airway disease, we enrolled 13 controls with obesity and 21 people with obesity and asthma: 8-isoprostane levels were higher in obese controls than in obese people with asthma (p < 0.01), and levels were inversely related to sinus symptoms (p = 0.02) and asthma control (p < 0.01).

INTERPRETATION

8-isoprostanes in nasal lavage are increased in obesity, and increased in Caucasians compared with African Americans. However, levels are higher in obese controls than obese people with asthma, and appear inversely related to symptoms of airway disease.

CLINICAL IMPLICATION

Airway 8-isoprostanes likely reflect complex oxidative signaling pathways, which are altered in obesity and those of different race, rather than being a simple marker of airway oxidative injury.

CAPSULE SUMMARY

Increased airway oxidative signaling (8-isoprostanes), may reflect normal physiology in the setting of obesity, as decreased levels are associated with disease activity in people with chronic sinonasal disease and asthma.

[A preliminary study on the biomarkers of local inflammation in allergic rhinitis]

Objective:This study aimed to explore the biomarkers in nasal secretion that can assist in the diagnosis of allergic rhinitis（AR） and can be used to evaluate the therapeutic effect of AR. Methods:Thirty-three patients with AR and 21 healthy controls were included. The nasal secretion of healthy controls and patients with AR（before and after treatment） were collected. The cytology, the concentrations of cytokines（IL-5, IL-6, IL-8, IL-33, IFN-γ） and inflammatory mediators（ECP, MPO） were detected. Then, we compared the differences of various biomarkers between healthy controls and AR patients（before and after treatment group）. And analyzed the correlation between each biomarkers/biomarkers difference value/the percentage of biomarkers difference value and clinical symptom score/ score difference value / the percentage of score difference value. Results:Compared with normal controls, the levels of ECP, IL-5, IL-6, IL-8, IL-33 and IFN-γ in nasal secretion of AR patients were significantly higher than those of normal controls（P<0.05）. There was no significant difference in MPO. After treatment, ECP decreased significantly（P<0.01）, inflammatory cell grade and eosinophil percentage are also decreased（P<0.01）. However, MPO, IL-5, IL-6, IL-8, IL-33 and IFN-γ did not change significantly. The difference value of ECP before and after treatment was correlated with the difference value of VAS score（r=0.348, P=0.047）. The difference value of IL-5 was correlated with the difference value of VAS score and rhinorrhea, the correlation coefficients were 0.406（P=0.019） and 0.429（P=0.013）, respectively. The difference value of eosinophil percentage in nasal secretion before and after treatment was correlated with nasal congestion, and the correlation coefficient was 0.383. The difference value of eosinophil percentage multiplied by inflammatory cell grade before and after treatment was correlated with VAS score（r=0.417, P=0.016） and nasal congestion difference value（r=0.519, P=0.002）. The percentage of difference value of IFN-γ before and after treatment was correlated with the percentage of difference value of VAS score / rhinorrhea / sneeze / total nasal symptom score. Conclusion:ECP, IL-6, IL-8 and IL-33 in nasal secretion are expected to be objective biomarkers for auxiliary diagnosis of AR. And ECP, IL-5, IFN-γ, eosinophil percentage multiplied by grade is expected to be an objective index to judge the improvement of patients' symptoms after treatment.

The Biology of Prostaglandins and Their Role as a Target for Allergic Airway Disease Therapy

Prostaglandins (PGs) are a family of lipid compounds that are derived from arachidonic acid via the cyclooxygenase pathway, and consist of PGD₂, PGI₂, PGE₂, PGF₂, and thromboxane B₂. PGs signal through G-protein coupled receptors, and individual PGs affect allergic inflammation through different mechanisms according to the receptors with which they are associated. In this review article, we have focused on the metabolism of the cyclooxygenase pathway, and the distinct biological effect of each PG type on various cell types involved in allergic airway diseases, including asthma, allergic rhinitis, nasal polyposis, and aspirin-exacerbated respiratory disease.

Correlation of Nasal Fluid Biomarkers and Symptoms in Patients with Persistent Allergic Rhinitis

OBJECTIVES

This study investigated whether the biomarkers present in nasal fluid reflect the severity of symptoms in patients with persistent allergic rhinitis (PAR).

METHODS

We enrolled 29 PAR patients complaining of nasal symptoms and testing positive to skin prick test. Patients' total nasal symptom score (TNSS) was measured and their nasal lavage fluid (NALF) was collected. The levels of biomarkers including Clara cell protein 16 (CC16), tryptase, and interleukin 5 (IL-5) in NALF were determined via enzyme-linked immunosorbent assay (ELISA).

RESULTS

PAR patients were classified into persistent mild and persistent moderate-to-severe groups according to the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines. The CC16 alone was significantly negatively correlated with TNSS (P < .05). Further, the CC16 level was significantly lower in persistent moderate-to-severe group than persistent mild group of patients (P < .05).

CONCLUSIONS

The levels of CC16 alone among several NALF biomarkers showed an inverse correlation with symptoms of PAR patients.