caa a22 4500 477119573 CHVBK 20180405111632.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00240052 doi (NATIONALLICENCE)springer-10.1007/BF00240052 Cytoprotective mechanisms in cultured cardiomyocytes [Elektronische Daten] [Hari Sharma, Joachim Stahl, Dirk Weisensee, Iris Löw-Friedrich] Tumor necrosis factor-α (TNF-α), a potent cytokine mainly secreted by macrophages exerts pleiotropic effects on different cell types. However, the intracellular mediators of its action are not yet well characterized. To get an insight into endogenous cytoprotective mechanisms, we developed an in vitro model based on cultured cardiomyocytes treated with TNF-α at which we examined gene expression of heat shock proteins (HSP-27, HSP-70 and ubiquitin). Cardiomyocytes were isolated from the hearts of 18 day old fetal mice by enzymatic dissociation and grown in minimum essential medium containing 10% fetal calf serum. Spontaneously contractile cells were serum deprived for 24 h and treated with TNF-α (25 ng/ml) for 1, 2, 4, 6, 8, 12, and 24 h After each incubation, cells were processed to extract total proteins for Western and total RNA for Northern blot analyses. TNF-α induced arrhythmias and cessation of spontaneous contractions in a concentration and time dependent manner. Steady state (ubiquitin) or undetectable mRNA levels (HSP-27, HSP-70) were drastically induced (> 4 fold for all three genes vs untreated control cells) by TNF-α, reaching maximal values between 6-8 h of stimulation. Thereafter, the expression of these stress genes declined but remained elevated as compared to control. By Western blot analysis, we found increased multiple bands of ubiquitin protein conjugates in TNF-a treated cells whereas no significant change in HSP-27 protein accumulation until 12 h was observed as compared to control. 24 h of TNF-α incubation resulted in partial cellular necrosis. Our results indicate that TNF-α induces in cardiomyocytes transiently gene expression for cytoprotective molecules like HSP-27, HSP-70 and ubiquitin, suggesting these stress proteins to participate in subsequent defense mechanisms, for example in postischemic myocardial recovery. (Mol Cell Biochem 160/161: 217-224, 1996) Kluwer Academic Publishers, 1996 TNF-α nationallicence heat shock proteins nationallicence cardiomyocytes nationallicence cytoprotection nationallicence Sharma Hari Cardiovascular and Molecular Biology Laboratory, Institute of Pharmacology, Erasmus University, Rotterdam, The Netherlands aut Stahl Joachim Max-Delbrück-Center for Molecular Medicine, Berlin, Germany aut Weisensee Dirk Center for Internal Medicine, J W. Goethe University Hospital, Frankfurt am Main, Germany aut Löw-Friedrich Iris Center for Internal Medicine, J W. Goethe University Hospital, Frankfurt am Main, Germany aut Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www.wkap.nl 160-161/1(1996-03-01), 217-224 0300-8177 160-161:1<217 1996 160-161 11010 https://doi.org/10.1007/BF00240052 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00240052 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sharma Hari Cardiovascular and Molecular Biology Laboratory, Institute of Pharmacology, Erasmus University, Rotterdam, The Netherlands aut NATIONALLICENCE 700 1- Stahl Joachim Max-Delbrück-Center for Molecular Medicine, Berlin, Germany aut NATIONALLICENCE 700 1- Weisensee Dirk Center for Internal Medicine, J W. Goethe University Hospital, Frankfurt am Main, Germany aut NATIONALLICENCE 700 1- Löw-Friedrich Iris Center for Internal Medicine, J W. Goethe University Hospital, Frankfurt am Main, Germany aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www.wkap.nl 160-161/1(1996-03-01), 217-224 0300-8177 160-161:1<217 1996 160-161 11010 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer