Conclusion
Crocin decreased airway inflammation, partially by inhibiting NF-κB and IL-17 and up-regulating Nrf2/HO-1 mRNA and protein expression levels.
Methods
Four different groups were formed by dividing forty male BALB/C mice: control group, OVA-sensitized group (OVA), OVA combined with crocin 30 mg/kg (OVA-Cr30), and the OVA combined with crocin 60 mg/kg (OVA-Cr60). In order to determine the total number of WBC and inflammatory cells infiltrating the lung, we utilized the bronchoalveolar lavage fluid for counting purposes. The mRNA and protein levels of Nrf2, HO-1, IL-17, and NF-κB in lung tissue were assessed through real-time PCR and western blot techniques.
Results
Crocin significantly prevented the increase of total WBC and inflammatory cells in the lung tissue (P<0.001 for all) and histopathological changes in OVA-sensitized mice. Furthermore, crocin displayed suppressive effects on the enhancement of NF-kB (P<0.01) and IL-17 (P<0.05) mRNA and protein levels in OVA-sensitized mice while preserving Nrf2 (P<0.01) and HO-1 (P<0.05) expression levels. Crocin effects became increasingly apparent when utilized at high concentrations.