Calcitonin Gene-Related Peptide Level in Cystic Fibrosis Patients

Calcitonin gene-related peptide (CGRP) has long been implicated in both the physiology and pathophysiology of the respiratory tract. The objective of our study was to determine the serum concentration of alpha CGRP (alpha CGRP) in cystic fibrosis (CF) that arises from mutations in the gene responsible for encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Currently, there are not many data in the literature about the role of CGRP in CF. The serum level of alpha CGRP was estimated using the enzyme-linked immunosorbent assay among 64 patients with CF and 31 healthy controls. The alpha CGRP concentration in the CF group was 62.51 +/- 15.45 pg/mL, while in the control group it was 47.43 +/- 8.06 pg/mL (p < 0.001). We also compared the level of alpha CGRP in CF patients according to the type of CFTR mutation. Homozygotes for Delta F508 had higher alpha CGRP levels than heterozygotes (67.9 +/- 10.2 vs. 54.5 +/- 18.3 pg/mL, p < 0.01). The level of this neuropeptide was statistically higher in patients with severe disease than in those with mild CF (p = 0.003) when patients were divided into three groups by spirometry results. alpha CGRP concentration was not correlated with age, sex, clinical parameters, and pulmonary function test results in the study participants. The results of our study suggest a significant increase in the concentration of alpha CGRP in the serum of patients with CF compared to the control group. This observation opens interesting possibilities for understanding the role of alpha CGRP in the context of CF pathophysiology.