Figure 5. Effects of NaHS on SIRT1 mRNA and protein expressions in CSE-stimulated epithelial A549 cells. A549 cells were cultured with and without 3% CSE and/or 100, 200, or 400μM NaHS for 48 h. (A) The mRNA level of SIRT1 was detected using Real-time PCR. (B) The protein level of SIRT1 was detected using Western blot. (C) Immunofluorescence staining for SIRT1 was performed on A549 cells treated with and without 3% CSE and 400μM NaHS for 48 h. *P<0.05, **P<0.01, significantly different from control cells [3%CSE (-) and NaHS (-)]; #P<0.05, ##P<0.01, significantly different from cells treated with 3%CSE only.