Downregulation of SIRT3 Aggravates Lung Ischemia Reperfusion Injury by Increasing Mitochondrial Fission and Oxidative Stress through HIF-1α-Dependent Mechanisms

Figure 6

Knockdown SIRT3 increased mitochondrial oxidative stress, decreased ATP content, and MMP by regulating HIF-1α after H/R in vitro. A lentiviral vector expressing shRNA targeting SIRT3 and HIF-1α individually was used to knockdown the expression of SIRT3 and HIF-1α. Cells were randomly divided into six groups: Control, H/R, H/R+shRNA, H/R+S (H/R+SIRT3 shRNA), H/R+H (H/R+HIF-1α shRNA), and H/R+H+S (H/R+SIRT3 shRNA+HIF-1α shRNA) groups. Cells and supernatants from each group were collected after 24 h reoxygenation. (a) SIRT3 and HIF-1α protein levels were detected by western blotting. (b, c) Expression of SIRT3 and HIF-1α protein relative to β-actin. (d) Cell viability of RAW264.7 macrophage cells determined by the CCK-8 kit. (e–g) MDA, SOD₂, and GSH levels in the supernatant. (h) ATP content. (i, j) MitoSOX fluorescence staining and fluorescence intensity. (k) Images showing the change in MMP. The data are expressed as ( for all panels), *.

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