Short Exposure to Ethanol Diminishes Caspase-1 and ASC Activation in Human HepG2 Cells In Vitro

International Journal of Molecular Sciences

Teodora Vrdoljak¹  Lukas Martin²  Ramona Sturm³  Jason-Alexander Hörauf³  Baolin Xu⁴  Borna Relja⁴  Andrea Janicova⁴  Shinwan Kany⁴  Ildiko Rita Dunay⁵ 

[1] Department of Diagnostic and Interventional Radiology, University Hospital Dubrava, University of Zagreb School of Medicine, HR-10000 Zagreb, Croatia;Department of Intensive Care and Intermediate Care, University Hospital RWTH Aachen, 52074 Aachen, Germany;Department of Trauma, Hand and Reconstructive Surgery, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany;Experimental Radiology, Department of Radiology and Nuclear Medicine, Otto von Guericke University Magdeburg, 39108 Magdeburg, Germany;Institute of Inflammation and Neurodegeneration, Otto von Guericke University Magdeburg, 39108 Magdeburg, Germany;

关键词: inflammation;    inflammasome;    caspase-1;    alcohol;    liver;    in vitro;   

DOI  :  10.3390/ijms21093196

来源: DOAJ

【 摘 要 】

This paper discusses how the assembly of pro-caspase-1 and apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) in macromolecular protein complexes, inflammasomes, activates caspase-1. The present study investigates the molecular mechanisms of inflammasome activation in HepG2 cells and examines how short exposures to ethanol (EtOH) affect inflammasome activation. HepG2 cells were treated with lipopolysaccharide (LPS), ATP or nigericin (NIG) in a two-step model. After LPS priming, ATP or NIG were added. As inhibitors, sodium orthovanadate (general inhibitor of tyrosine phosphatases), AC-YVAD-CMK (caspase-1 inhibitor) or AZ10606120 (purinergic receptor P2X7R inhibitor) were applied after LPS priming. To monitor the inflammasome activation, the caspase-1 activity, ASC speck formation, reactive oxygen species (ROS) production and cell death were analyzed. To elucidate the mechanistical approach of EtOH to the inflammasome assembly, the cells were treated with EtOH either under simultaneous LPS administration or concurrently with ATP or NIG application. The co-stimulation with LPS and ATP induced a significant ASC speck formation, caspase-1 activation, cell death and ROS generation. The inhibition of the ATP-dependent purinoreceptor P2X7 decreased the caspase-1 activation, whereas sodium orthovanadate significantly induced caspase-1. Additional treatment with EtOH reversed the LPS and ATP-induced caspase-1 activation, ASC speck formation and ROS production. The ASC speck formation and caspase-1 induction require a two-step signaling with LPS and ATP in HepG2 cells. Inflammasome activation may depend on P2X7. The molecular pathway of an acute effect of EtOH on inflammasomes may involve a reduction in ROS generation, which in turn may increase the activity of tyrosine phosphatases.

【 授权许可】

Unknown