Impact of control interventions on lung gene expression in post-natal lung development

During the studies of post-natal lung development in the laboratory C57BL/6 mouse, broad spectrums of interventions are applied by intraperitoneal (i.p.) injections. We explored whether injection of saline, tamoxifen, “scrambled” antagomiRs (to control studies that target microRNA with antagomiRs), migloyl or water, in well-established protocols, had any impact on the post-natal gene expression in mouse lungs. Overall design: Pups were randomized on the day of birth and litters were balanced. Saline (daily treatment) group was treated via i.p. injection (25µl/g) daily from the postnatal day (P)1 to P13. Scramble antagomiR controls: Scrambled 1 (Custom miRCURY™ LNA Inhibitor probe, batch number 184196, Exiqon) and Scrambled 2 (Custom miRCURY™ LNA Inhibitor probe, New scramble control design, Exiqon) were applied at P1 and P3, by i.p. injection (10 mg/kg) dissolved in nuclease-Free Water (Ambion). Nuclease-Free Water (Ambion) was applied via i.p injection at P1 and P3 at (10µl/g). At P14 mice from Saline (daily treatment), Scrambled 1, Scrambled 2, Water and Untreated groups were sacrificed. Tamoxifen (Sigma-Aldrich) was applied at P1 and P2, by i.p. injection (0.4 mg; 25 µl) dissolved in Miglyol. Migloyl was applied at P1 and P2 at 25 µl via i.p. injection. Saline (treatment day 1+2) was applied at P1 and P2 at 25 µl via i.p. route. At P6 mice from Tamoxifen, Migloyl and Saline (treatment day 1+2) treatment groups were sacrificed.