The presence of allergic rhinitis (AR) is an increased risk factor for the occurrence of bronchial asthma (BA). Nerve growth factor (NGF), in addition to its key role in the development and differentiation of neurons, may also be an important inflammatory factor in AR and BA. However, the pathogenesis of the progression of AR to BA remains to be elucidated. The present study aimed to investigate the ability of NGF to mediate nasobronchial interactions and explore possible underlying molecular mechanisms. In the present study, an AR mouse model was established and histology of nasal mucosa tissue injury was determined. The level of phenylethanolamine N‑methyl transferase in adrenal medulla was determined by immunofluorescence. Primary adrenal medullary chromaffin cells (AMCCs) were isolated and cultured from the adrenal medulla of mice. The expression levels of synaptophysin (SYP), STAT1, JAK1, p38 and ERK in NGF‑treated and untreated AMCCs were detected by reverse‑transcription‑quantitative PCR and western blotting. The epinephrine (EPI) and norepinephrine (NE) concentrations were measured by ELISA. It was found that the expression of SYP in AMCCs was enhanced in the presence of NGF, whereas, the concentration of EPI decreased significantly under the same conditions. Furthermore, NGF mediated the phenotypic and functional changes of AMCCs, resulting in decreased EPI secretion via JAK1/STAT1, p38 and ERK signaling. In conclusion, these findings could provide novel evidence for the role of NGF in regulating neuroendocrine mechanisms.
Keywords: adrenal medulla chromaffin cells; allergic rhinitis; bronchial asthma; epinephrine; nerve growth factor.