Changes in Essential Fatty Acids and Ileal Genes Associated with Metabolizing Enzymes and Fatty Acid Transporters in Rodent Models of Cystic Fibrosis

Cystic fibrosis (CF), the result of mutations in the CF transmembrane conductance regulator (CFTR), causes essential fatty acid deficiency. The aim of this study was to characterize fatty acid handling in two rodent models of CF; one strain which harbors the loss of phenylalanine at position 508 (Phe508del) in CFTR and the other lacks functional CFTR (510X). Fatty acid concentrations were determined using gas chromatography in serum from Phe508del and 510X rats. The relative expression of genes responsible for fatty acid transport and metabolism were quantified using real-time PCR. Ileal tissue morphology was assessed histologically. There was an age-dependent decrease in eicosapentaenoic acid and the linoleic acid:alpha-linolenic acid ratio, a genotype-dependent decrease in docosapentaenoic acid (n-3) and an increase in the arachidonic acid:docosahexaenoic acid ratio in Phe508del rat serum, which was not observed in 510X rats. In the ileum, Cftr mRNA was increased in Phe508del rats but decreased in 510X rats. Further, Elvol2, Slc27a1, Slc27a2 and Got2 mRNA were increased in Phe508del rats only. As assessed by Sirius Red staining, collagen was increased in Phe508del and 510X ileum. Thus, CF rat models exhibit alterations in the concentration of circulating fatty acids, which may be due to altered transport and metabolism, in addition to fibrosis and microscopic structural changes in the ileum.

Automated summary

This study aimed to investigate the characteristics of essential fatty acid deficiency caused by cystic fibrosis (CF), which is the result of mutations in the CF transmembrane conductance regulator (CFTR). Two rodent models of CF were studied: one strain with a loss of phenylalanine at position 508 (Phe508del) in CFTR and the other lacking functional CFTR (510X). Fatty acid concentrations were measured in the serum, and the expression of genes related to fatty acid transport and metabolism was quantified. Histological assessment of the ileal tissue was also performed. The results showed genotype- and age-dependent alterations in fatty acid concentration, as well as changes in gene expression and tissue morphology. These findings suggest that CF rat models exhibit abnormalities in the handling of fatty acids, possibly due to altered transport and metabolism, as well as fibrosis and structural changes in the ileum.