Abstract: Objective To explore the relationship between the expression of AQP1 gene and Schwann cells swelling. Methods The AQP1 expression in Schwann cells of mouse facial nerve tissues was detected by immunofluorescent staining. The RNA interference by lentiviral transduction was used to specifically down-regulate AQP1 expression in Schwann cells. AQP1-shRNA and scr-shRNA transduced cells were observed daily during AQP1-KD by using phase contrast microscopy. Cell volume of scr-shRNA and AQP1 shRNA treated cells was measured daily from the day of treatment, through day 6. Cell viability was measured by MTT assay. Apoptosis effects of AQP1 shRNA on Schwann cells were detected by flow cytometry. Results Schwann cell primary cultures maintained a high level of AQP1 water channels, representing an ideal cell model to study the role of AQP1 in the facial nerve. AQP1 expression in AQP1-shRNA cells was significantly lower compared to cells transduced with only the scr-shRNA by Real-time PCR and Western Blot analysis(P<0.05).AQP1 gene silencing resulted in a cell shrinkage phenotype , as validated by cell volume determinations(P<0.01). MTT assay showed that the cell viability in AQP1-shRNA cells was lower compared to cells transduced with scr-shRNA(P<0.05). Flow cytometry assay showed that AQP1gene silencing could not affect the apoptosis and necrosis rates of Schwann cells. Conclusion AQP1 is an important factor responsible for the fast water transport of cultured Schwann cells; AQP1 inhibition might provide a new therapeutic alternative for the treatment of some forms of facial nerve edema.

Key words: AQP1, RNAi, lentivirus, facial paralysis, gene therapy