Biomaterial Database

Sensitization by interleukin-6 of rat hepatocytes to tumor necrosis factor alpha-induced apoptosis. 2003

Ulrike Böer, and Alexandra Fennekohl, and Gerhard P Püschel

Institut für Ernährungswissenschaft, Universität Potsdam, Abt. Biochemie der Ernährung, Arthur-Scheunert-Allee 114-116, D-14558, Bergholz-Rehbrücke, Germany.

OBJECTIVE Tumor necrosis factor (TNF) elicits hepatocyte apoptosis in toxic liver injury and is also central in hepatocyte proliferation after partial hepatectomy. In both circumstances interleukin (IL)-6 levels are also elevated. In mouse liver IL-6 attenuated Fas receptor-mediated apoptosis indicating its interference with pro-apoptotic signal chains. It was, therefore, the aim to examine the modulation by IL-6 of TNFalpha-induced apoptosis in rat hepatocytes. METHODS Primary rat hepatocytes were treated with IL-6 prior to induction of apoptosis with TNFalpha/actinomycin D or anti-Fas antibody M-20. Apoptosis was detected by determination of caspase-3 activation and bisbenzimide staining of condensed nuclei. Expression of TNFalpha receptors was analyzed by semi-quantitative polymerase chain reaction and ligand binding studies with [125I]-TNFalpha. RESULTS IL-6 treatment doubled TNFalpha/actinomycin D-induced caspase-3 activity and significantly enhanced chromatin condensation. By contrast IL-6 inhibited Fas-induced increase in caspase-3 activity by 45% and significantly reduced chromatin condensation. IL-6 increased the mRNA level of TNF-R1 1.35-fold and augmented cell surface binding of [125I]-TNFalpha 3-fold. The latter and TNFalpha-mediated caspase activation was attenuated by prostaglandin E(2). CONCLUSIONS IL-6 - in contrast to its anti-apoptotic modulation of the Fas-induced pathway - exerted a pro-apoptotic effect on the TNFalpha/actinomycin D-induced apoptosis by increasing the number of TNF-R on hepatocytes.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D002843	Chromatin	The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.	Chromatins
D003609	Dactinomycin	A compound composed of a two CYCLIC PEPTIDES attached to a phenoxazine that is derived from STREPTOMYCES parvullus. It binds to DNA and inhibits RNA synthesis (transcription), with chain elongation more sensitive than initiation, termination, or release. As a result of impaired mRNA production, protein synthesis also declines after dactinomycin therapy. (From AMA Drug Evaluations Annual, 1993, p2015)	Actinomycin,Actinomycin D,Meractinomycin,Cosmegen,Cosmegen Lyovac,Lyovac-Cosmegen,Lyovac Cosmegen,Lyovac, Cosmegen,LyovacCosmegen
D004357	Drug Synergism	The action of a drug in promoting or enhancing the effectiveness of another drug.	Drug Potentiation,Drug Augmentation,Augmentation, Drug,Augmentations, Drug,Drug Augmentations,Drug Potentiations,Drug Synergisms,Potentiation, Drug,Potentiations, Drug,Synergism, Drug,Synergisms, Drug
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014409	Tumor Necrosis Factor-alpha	Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.	Cachectin,TNF-alpha,Tumor Necrosis Factor Ligand Superfamily Member 2,Cachectin-Tumor Necrosis Factor,TNF Superfamily, Member 2,TNFalpha,Tumor Necrosis Factor,Cachectin Tumor Necrosis Factor,Tumor Necrosis Factor alpha
D015232	Dinoprostone	The most common and most biologically active of the mammalian prostaglandins. It exhibits most biological activities characteristic of prostaglandins and has been used extensively as an oxytocic agent. The compound also displays a protective effect on the intestinal mucosa.	PGE2,PGE2alpha,Prostaglandin E2,Prostaglandin E2alpha,PGE2 alpha,Prepidil Gel,Prostaglandin E2 alpha,Prostenon,E2 alpha, Prostaglandin,E2, Prostaglandin,E2alpha, Prostaglandin,Gel, Prepidil,alpha, PGE2,alpha, Prostaglandin E2
D015850	Interleukin-6	A cytokine that stimulates the growth and differentiation of B-LYMPHOCYTES and is also a growth factor for HYBRIDOMAS and plasmacytomas. It is produced by many different cells including T-LYMPHOCYTES; MONOCYTES; and FIBROBLASTS.	Hepatocyte-Stimulating Factor,Hybridoma Growth Factor,IL-6,MGI-2,Myeloid Differentiation-Inducing Protein,Plasmacytoma Growth Factor,B Cell Stimulatory Factor-2,B-Cell Differentiation Factor,B-Cell Differentiation Factor-2,B-Cell Stimulatory Factor 2,B-Cell Stimulatory Factor-2,BSF-2,Differentiation Factor, B-Cell,Differentiation Factor-2, B-Cell,IFN-beta 2,IL6,Interferon beta-2,B Cell Differentiation Factor,B Cell Differentiation Factor 2,B Cell Stimulatory Factor 2,Differentiation Factor 2, B Cell,Differentiation Factor, B Cell,Differentiation-Inducing Protein, Myeloid,Growth Factor, Hybridoma,Growth Factor, Plasmacytoma,Hepatocyte Stimulating Factor,Interferon beta 2,Interleukin 6,Myeloid Differentiation Inducing Protein,beta-2, Interferon