title: Hepatitis C virus-induced hepatocyte cell death and protection by inhibition of apoptosis.
abstract: Chronic hepatitis C virus (HCV) infection results in progressive liver fibrosis leading to cirrhosis and liver cancer. The mechanism for this remains unclear but hepatocyte apoptosis is thought to play a major role. Hepatocyte apoptosis in human liver tissue was determined by immunohistochemistry for cytokeratin 18 (M30 CytoDEATH) and cleaved poly(ADP-ribose) polymerase (PARP). In vitro studies were performed with replication-defective recombinant adenoviruses expressing HCV proteins (rAdHCV) to study the effects of HCV on cell death in Huh7 cells, primary mouse hepatocytes (PMoHs) and primary human hepatocytes (PHHs). Cell viability and apoptosis were studied using crystal violet assays and Western blots probed for cleaved caspase-3 and cleaved PARP, with and without treatment with the pan-caspase inhibitor Q-VD-OPh and necrostatin-1. Liver tissue of HCV-infected patients expressed elevated levels of apoptotic markers compared with HCV-negative patients. rAdHCV infection reduced cell viability compared with uninfected controls and cells infected with control virus (rAdGFP). Huh7, PMoHs and PHHs infected with rAdHCV showed significantly increased levels of apoptotic markers compared with uninfected controls and rAdGFP-infected cells. In rAdHCV-infected Huh7, treatment with Q-VD-OPh and necrostatin-1 both improved cell viability. Q-VD-Oph also reduced cleaved PARP in rAdHCV-infected Huh7 and PMoHs. Hepatocyte apoptosis is known to be increased in the livers of HCV-infected patients. HCV promoted cell death in primary and immortalized hepatocytes, and this was inhibited by Q-VD-OPh and necrostatin-1. These findings indicate that HCV-induced cell death occurs by both apoptosis and necroptosis, and provide new insights into the mechanisms of HCV-induced liver injury.
authors: Department of Gastroenterology and Hepatology, Austin Hospital, Heidelberg, Victoria, Australia.|Department of Medicine, Austin Hospital, University of Melbourne, Heidelberg, Victoria, Australia.
authors: Eu Jin
authors: EJ
authors: Lim
authors: Department of Medicine, Austin Hospital, University of Melbourne, Heidelberg, Victoria, Australia.
authors: Korri
authors: K
authors: El Khobar
authors: Department of Medicine, Austin Hospital, University of Melbourne, Heidelberg, Victoria, Australia.
authors: Ruth
authors: R
authors: Chin
authors: Department of Medicine, Austin Hospital, University of Melbourne, Heidelberg, Victoria, Australia.
authors: Linda
authors: L
authors: Earnest-Silveira
authors: Department of Gastroenterology and Hepatology, Austin Hospital, Heidelberg, Victoria, Australia.|Department of Medicine, Austin Hospital, University of Melbourne, Heidelberg, Victoria, Australia.
authors: Peter W
authors: PW
authors: Angus
authors: Department of Virology, Robert Koch Institute, Berlin, Germany.
authors: C-Thomas
authors: CT
authors: Bock
authors: Walter and Eliza Hall Institute, Parkville, Victoria, Australia.
authors: Ueli
authors: U
authors: Nachbur
authors: Walter and Eliza Hall Institute, Parkville, Victoria, Australia.
authors: John
authors: J
authors: Silke
authors: Department Infectious Diseases, Austin Hospital, Heidelberg, Victoria, Australia.|Department of Medicine, Austin Hospital, University of Melbourne, Heidelberg, Victoria, Australia.
authors: Joseph
authors: J
authors: Torresi
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000378:metabolism; D000818:Animals; D017209:Apoptosis; D020169:Caspases / Q000032:analysis; D002470:Cell Survival; D004791:Enzyme Inhibitors / Q000378:metabolism; D016174:Hepacivirus / Q000502:physiology*; D006526:Hepatitis C / Q000473:pathology*; D022781:Hepatocytes / Q000187:drug effects / Q000502:physiology* / Q000821:virology*; D006801:Humans; D007093:Imidazoles / Q000378:metabolism; D007211:Indoles / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D009336:Necrosis; D011804:Quinolines / Q000378:metabolism
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D004791:Enzyme Inhibitors; D007093:Imidazoles; D007211:Indoles; D011804:Quinolines; C507699:necrostatin-1; C468548:quinoline-val-asp(OMe)-CH2-OPH; D020169:Caspases