Abstract: PO0446
AMPK Activation Alleviates TNF-α Induced Human Umbilical Vein Endothelial Cell Monolayer Permeability Increase
Session Information
- AKI: Novel Insights
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 103 AKI: Mechanisms
Authors
- Huang Devine, Zheng, Janssen Research and Development LLC, Spring house, Pennsylvania, United States
- Pocai, Alessandro, Janssen Research and Development LLC, Spring house, Pennsylvania, United States
- Leonard, James, Janssen Research and Development LLC, Spring house, Pennsylvania, United States
Group or Team Name
- Cardiovascular & Metabolism
Background
The abnormal structure and function of the renal microvasculature contributes to acute kidney injury (AKI) pathophysiology by reducing regional blood flow especially in the outer medulla. AKI results in marked increases in local and systemic cytokine levels. IL-1α, IL-6, and TNF-α orchestrate various inflammatory reactions increasing endothelial permeability due to loss of endothelial monolayer and alteration of endothelial cell-cell junctions.
AMP-activated protein kinase (AMPK) has been reported to play a protective role in vascular function, mainly through eNOS phosphorylation, inhibition of ROS formation and stimulating mitochondrial biogenesis. In addition, AMPK has been reported to regulate the assembly and disassembly of epithelial tight junction.
Objectives: Our aims were to investigate whether a direct small molecule AMPK activator could preserve endothelial cell monolayer integrity when challenged by TNF-α treatment, and to investigate the potential mechanisms.
Methods
Structural and functional integrity of human umbilical vascular endothelial cells (HUVECs) monolayer was evaluated by measuring permeability, and caspase 3/7 activity was measured to reflect apoptotic cell death. TNF-α was used to induce injury. AMPK activation was confirmed by measurement of pACC. Data were analyzed using 1-way ANOVA.
Results
10, 30, and 100 ng/ml TNF-α significantly induced HUVEC monolayer permeability after 24 hr treatment, with 11.2-, 8.1-, and 8.1-fold increases, respectively. Direct allosteric AMPK activator (CpdA) protected against permeability induced by 24 hr of 100 ng/ml TNF-α treatment, with a maximum reduction of 57.6% permeability at 3 mM. SB 203580, a p38 MAPK inhibitor, decreased the permeability by about 62.5%. 100 ng/ml TNF-α treatment for 24 hr increased apoptosis by 2.8-fold. CpdA treatment significantly protected cells from apoptosis in a dose dependent manner. TNF-α treatment for 6 hr increased HUVEC permeability (~6.4-fold), which was reduced (40.6% reduction) by CpdA treatment. Cells incubated with CpdA maintained their shape and cell-cell contacts and showed less intercellular gaps when compared to those treated with DMSO vehicle control.
Conclusion
AMPK activation alleviated endothelial leakage, potentially via decreasing apoptosis and maintaining cell-cell contacts. Our data supports AMPK activation as a novel therapeutic approach for AKI.
Funding
- Commercial Support – Johnson & Johnson