Anti-nerve growth factor antibody improves airway hyperresponsiveness by down-regulating RhoA

The pathogenesis of asthma is complex and continues to be considered as a challenging subject. Some studies have shown that nerve growth factor (NGF) participates in the pathogenesis of asthma, but the mechanism of airway contraction caused by NGF is still unclear.

Our aim was to discuss the effect of anti-NGF antibody on RhoA expression, and further explore the role of NGF in airway hyperresponsiveness (AHR).

Thirty female BALB/c mice were divided into three groups randomly: control group (group C, n = 10), asthma group (group A, n = 10) and anti-NGF antibody intervention group (group N, n = 10). The asthmatic mice were stimulated by OVA suspension, the intervention mice were given nasal instillation of anti-NGF antibody before the stimulation. Airway responsiveness, eosinophils, IL-13, IFN-γ were measured. The protein expression and mRNA level of NGF and RhoA were detected by immunohistochemical and Real Time-PCR (RT-PCR) analyses.

Airway responsiveness, eosinophils and IL-13 levels in group A were significantly increased compare with the other groups, and significantly decreased in group N than those in group A. IFN-γ level was significantly reduced in group A and increased in group N. Immunohistochemistry and RT-PCR analyses showed that the protein expression and mRNA level of NGF and RhoA were significantly increased in group A and significantly decreased in group N.

NGF participates in the pathogenesis of asthma in mice. Anti-NGF antibody can inhibit airway inflammation and alleviate AHR by down-regulating the protein expression and mRNA level of RhoA.