HMOX1, a 32 kD protein, is an inducible isoform in response to stress such as oxidative stress,hypoxia, heavy metals and cytokines [34,35]. As prostaglandin-endoperoxide synthase COX2is an enzyme that mediates oxidative stress [36,37]. As shown in Fig 4A, HMOX1 mRNA expressionsignificantly increased to 1.99±0.60, and 2.27±0.96 fold, respectively, in HCECs exposedto increasing hyperosmolarity, 400 and 450 mOsM (p<0.05, p<0.05, n = 5, respectively)for 4 hours when compared with the isosmotic group, as evaluated by RT-qPCR. COX2mRNA levels also dramatically increased to 6.48±1.73, and 11.29±6.29 fold, respectively, inHCECs when switch from normal medium to increasing hyperosmolarity, 400 or 450 mOsM(p<0.01, p<0.01, n = 5, respectively) for 4 hours. Hyperosmolarity induced HMOX1 andCOX2 were confirmed at protein levels as determined by immunofluorescent staining (Fig 4B).The immunoreactivity of HMOX1 and COX2 were located mainly in the cytoplasm of primaryHCECs. The intensity of HMOX1 and COX2 immunoreactivity was significantly induced in an osmolarity-dependent manner in HCECs exposed to media with increasing hyperosmolarity(400 and 450 mOsM) for 24 hours. This pattern of response to hyperosmolarity by HCECswas further confirmed by Western blot analysis, which showed that these two oxygenases, 32kD HMOX1 and 65 kD COX2, were indeed induced osmolarity-dependently by increasinghyperosmolarity in HCECs (Fig 4C).
การแปล กรุณารอสักครู่..