KLF6 alleviates hepatic ischemia-reperfusion injury by inhibiting autophagy

Abstract

Hepatic ischemia-reperfusion (I/R) injury, a common clinical complication of liver transplantation, gravely affects patient prognosis. Krüppel-like factors (KLFs) constitute a family of C2/H2 zinc finger DNA-binding proteins. KLF6, a member of the KLF protein family, plays crucial roles in proliferation, metabolism, inflammation, and injury responses; however, its role in HIR is largely remains unknown. After I/R injury, we found that KLF6 expression in mice and hepatocytes was significantly upregulated. Mice were then subjected to I/R following injection of shKLF6- and KLF6-overexpressing adenovirus through the tail vein. KLF6 deficiency markedly exacerbated liver damage, cell apoptosis, and activation of hepatic inflammatory responses, whereas hepatic overexpression of KLF6 in mice produced the opposite results. In addition, we knocked out or overexpressed KLF6 in AML12 cells before exposing them to a hypoxia-reoxygenation challenge. KLF6 knockout decreased cell viability and increased hepatocyte inflammation, apoptosis, and ROS, whereas KLF6 overexpression had the opposite effects. Mechanistically, KLF6 inhibited the overactivation of autophagy at the initial stage, and the regulatory effect of KLF6 on I/R injury was autophagy-dependent. CHIP-qPCR and luciferase reporter gene assays confirmed that KLF6 bound to the promoter region of Beclin1 and inhibited its transcription. Additionally, KLF6 activated the mTOR/ULK1 pathway. Finally, we performed a retrospective analysis of the clinical data of liver transplantation patients and identified significant associations between KLF6 expression and liver function following liver transplantation. In conclusion, KLF6 inhibited the overactivation of autophagy via transcriptional regulation of Beclin1 and activation of the mTOR/ULK1 pathway, thereby protecting the liver from I/R injury. KLF6 is expected to serve as a biomarker for estimating the severity of I/R injury following liver transplantation.

Unveiling the Crucial Roles of O2•–and ATP in Hepatic Ischemia–Reperfusion Injury Using Dual-Color/Reversible Fluorescence Imaging

“…First, a HIRI model in hepatocytes was established by glucose-serum-oxygen deprivation and subsequent reperfusion, which was validated by a series of hepatocyte injury markers such as ALT, AST, tumor necrosis factor-α (TNF-α), and lactate dehydrogenase (LDH). , As depicted in Figure S11, the levels of ALT and AST were significantly elevated in HIRI hepatocytes in comparison with control hepatocytes. Interestingly, increases of TNF-α and LDH release were observed in the HIRI group rather than in control group.…”

PPARβ/δ activation protects against hepatic ischaemia–reperfusion injury

“…PPARβ/δ‐overexpression (OE–PPARβ/δ) and PPARβ/δ shRNA‐knockdown (shPPARβ/δ) mice were constructed by tail vein injection of adenovirus‐mediated PPARβ/δ overexpression or knockdown vectors (1 × 109 pfu per mouse), respectively, and the mouse HIRI model was constructed after 3 days (Figure S1A). 26 Mice were given an intraperitoneal injection of .9% saline (10 mL/kg), GW0742 (.3 mg/kg, IP bolus), or GSK0660 (1 mg/kg, IP bolus) 30 min before I/R (Figure S1B).…”

Skimmianine attenuates liver ischemia/reperfusion injury by regulating PI3K–AKT signaling pathway-mediated inflammation, apoptosis and oxidative stress

“…AML12 cells from the H/R group were incubated in serum-free medium in a triple-gas incubator (5% CO 2 , 94% N 2 , 1% O 2 ) for 12 h to complete this step of hypoxia. Immediately after the completion of hypoxia, the serum-free medium was replaced with normal medium containing 10% fetal bovine serum (FBS) for reoxygenation, and the cells were placed in the normal incubator for 6 h to complete the reoxygenation 26 .…”