Abstract: PUB026
Phillygenin Alleviates Sepsis-Associated AKI by Regulating Autophagy and Inflammasome Activation via the TLR4/NF-κB/NLRP3 Signaling Pathway
Session Information
Category: Acute Kidney Injury
- 103 AKI: Mechanisms
Authors
- Lv, Jinlei, Department of Nephrology, the First Affiliated Hospital of Nanchang University, NanChang, JiangXi, China
- Wang, Zhifang, Department of Nephrology, Huanggang Central Hospital of Yangtze University, HuangGang, Hubei, China
Background
Acute kidney injury (AKI) is a common and severe complication of sepsis, not only aggravating renal function damage but also significantly increasing the mortality rate. Phillygenin (PHI), as a natural active monomer, possesses multiple biological activities such as anti-inflammation, antioxidation, and regulation of cell signaling pathways. but whether it can alleviate SA-AKI by regulating the TLR4/NF-κB/NLRP3 pathway and autophagy has not been systematically verified.
Methods
In vitro model of SA-AKI was established by inducing HK-2 cells with LPS. the concentration of PHI was determined to be 50 μg/mL through the experiment. The protective effect of PHI was systematically evaluated by detecting the levels of oxidative stress, the expression of key molecules in the inflammatory pathway, autophagy and Caspase-1. also we explored whether PHI could alleviate SA-AKI by inhibiting the TLR4/NF-κB/NLRP3 inflammatory pathway
Results
Compared with the LPS group, the mRNA levels of IL-6, TNF-α, and IL-18 were increased, and the inflammatory indicators decreased after PHI treatment, indicating that PHI had a significant anti-inflammatory effect. In the JC-1 staining, the green fluorescence of cells increased under LPS stimulation, and the membrane potential decreased. After PHI treatment, the red/green ratio increased, and the mitochondrial membrane potential was restored. Flow cytometry showed that the generation of ROS in the LPS group was significantly increased, but it decreased significantly after PHI treatment. WB and qPCR detection showed that the protein levels of TLR4, NLRP3, NF-κB P65, P62, and LC3B were significantly decreased after PHI treatment. After TLR4 knockout, the NLRP3 inflammasome and autophagy indicators in the LPS + PHI and LPS + si-TLR4 groups decreased, but in the LPS + PHI + siTLR4 group, some indicators did not significantly decrease compared with the LPS + PHI group. The CQ blocking experiment showed that after blocking the autophagic flux, the protective effect of PHI partially disappeared.
Conclusion
PHI exerted protective effects in HK- 2 cells by inhibiting the TLR4/NF-κB/NLRP3 inflammatory pathway, improving autophagy and the oxidative stress state. TLR4 silencing and CQ blocking experiments further confirmed that the improvement of inflammation and autophagy by PHI mainly relied on blocking TLR4 signaling.
Acknowledgment
this work was supported by the NSFC No.82060140,81660129
Funding
- Government Support – Non-U.S.