Hepatocyte Senescence is Initiated through a Klf6-p21 Mechanism which mediates the Production of Cxcl14, a Novel Prognostic Biomarker of Acute Liver Failure

• DOI: 10.1124/jpet.122.294240
• Publication Date: 2023-05-18T14:23:00Z
• Authors: David Umbaugh; Nga Nguyen; Giselle Sanchez G...; Cecilia Villanueva; Bruno Hagenbuch; Anup Ramachandran; Hartmut Jaeschke
• Keywords: Senescence

<b>Abstract ID 29424</b> <b>Poster Board 226</b> <b>Background:</b> Acute liver failure (ALF) is characterized by hepatic encephalopathy, coagulopathy, peripheral vasodilation and organ failure. The majority of all ALF cases in the United States UK are due to acetaminophen (APAP) overdose. An extensive body work has elucidated molecular mechanisms hepatocyte necrosis during APAP overdose, but detailed involved development have been largely unexplored. Previous demonstrated that a severe overdose (600 mg/kg) results prolonged injury, impaired regeneration sustained inhibition cell cycle progression mediated through p21. Cell senescence fate resulting arrest predominantly controlled p16 or p21 dependent pathways. Some senescent cells acquire associated secretory phenotype (SASP) which consists bioactive signals can influence microenvironment. Why some develop SASP, others do not remains elusive, however specific program governing thought vary depending on type inducing factors. Klf6 induced senescence, promotes expression, when overexpressed decreases proliferation hepatocellular carcinoma. <b>Aim:</b> We hypothesized hepatocytes SASP directly impedes recovery, induction Klf6-p21 axis, ultimately drives ALF. <b>Approach Results:</b> Initial bioinformatic analysis flow-sorted perinecrotic after moderate (300 revealed these express both Klf6, Cxcl14 (a constituent). Further, we fractionated non-parenchymal confirmed primary source Cxcl14. In male female mice, found dose-dependent Klf6/p21 persistent circulating levels plasma. parallel experiments, targeted either with senolytic drugs, dasatinib quercetin, constituent neutralizing antibody. targeting greatly reduced APAP-induced injury while failed injury. Experiments analyzing human livers Klf6-p21-Cxcl14 axis upregulated compared healthy controls. To confirm link between Cxcl14, utilized CRISPRa HepG2 system where transcriptionally activated strongly expression. redox-responsive protein previously complex III an initiating event toxicity cascade. Therefore, conducted further experiments <i>in&nbsp;vitro</i> inhibiting Antimycin A resulted increased <b>Conclusions:</b> Collectively, our data suggests oxidative stress leads continued elevation p21-mediated production Importantly, find plasma accurately predict patient survival, as it gradually declines surviving patients consistently elevated non-surviving patients. This confirms initiation critical mechanistic events leading