[Decreased SIRT1 expression is related to bronchopulmonary dysplasia in premature infants after oxygen exposure].

Objective To observe silent information regulator 1 (SIRT1) expression in the peripheral blood mononuclear cells (PBMCs), and explore the relationship between SIRT1 expression and bronchopulmonary dysplasia (BPD) in premature infants after oxygen exposure. Methods Premature infants with 28 to 30 weeks' gestation were divided into three groups according to the fraction of inspiration O2 (FiO2): low-oxygen group with FiO2<30%, medium-oxygen group with FiO2 being 30%~40%, and high-oxygen group with FiO2≥40%; other premature infants with 28 to 30 weeks' gestation and without inspiration O2 served as a control group. The children's clinical data and residual blood samples obtained from the routine examination of 0, 7, 14 and 28 days of hospitalization were collected, and PBMCs were isolated and cryopreserved in -80DegreesCelsius refrigerator. Twenty children diagnosed with BPD were enrolled as a BPD group, and other sex-matched 20 children without BPD were randomly chosen as a non-BPD group. The children's clinical data were retrospectively analyzed, and SIRT1 expression in the PBMCs of each group was measured by Western blotting. Furthermore, the role of SIRT1 expression in the occurrence and development of BPD in premature infants was also analyzed. Results Compared with the control group, SIRT1 expression in the medium-oxygen group and the high-oxygen group significantly decreased with the increase of FiO2, and the expression in the low-oxygen group and the control group was almost at a similar level. Compared with the non-BPD group, SIRT1 expression in the BPD group of 14 and 28 days was significantly reduced. Conclusion There is a certain relationship between the decreased SIRT1 expression in PBMCs and the occurrence of BPD in premature infants after continuous and high-concentration oxygen exposure.