Left-ventricular expression of interleukin-6 messenger-RNA higher in idiopathic dilated than in ischemic cardiomyopathy.
During end-stage heart failure, plasma levels of interleukin-6 (IL6) are elevated. This cytokine exerts a negative inotropic influence on the myocardium. The production site of IL6 is unclear. We examined the hypothesis that IL6 in end-stage heart-failure patients is produced in the myocardium itself and is differentially regulated according to etiology. Cardiac tissue was obtained from 27 patients (idiopathic dilated cardiomyopathy, (DCM) 9/6 m/f, age 46 +/- 14 y; ischemic cardiomyopathy (ICM), 11/1 m/f, age 55 +/- 8 y) at the time of transplantation. The tissue was subjected to IL6 Northern-blot analysis. Signals were quantified by densitometric scanning after normalization to G3 PDH mRNA. Data were compared by Mann-Whitney test between DCM and ICM patients, divided by chamber origin. IL6 transcripts were found in all patients. In DCM, left-ventricular IL6 mRNA expression was higher than in ICM (p = 0.006). Median right-ventricular as well as left- and right-atrial IL6 mRNA expression was not significantly different in both groups. In summary, in end-stage heart failure, IL6 mRNA is consistently expressed in the myocardium. Left-ventricular expression is higher in DCM than in ICM. These data support the concept of a potentially reversible inflammatory component in the etiology of DCM which is more pronounced than in patients with ICM of comparable clinical severity.
Department of Cell Biology and Ultrastructural Research, Institute for Arteriosclerosis Research, Westfalian Wilhelms University, Münster, Germany.
G
G
Plenz
Z F
ZF
Song
S
S
Reichenberg
T D
TD
Tjan
H
H
Robenek
M C
MC
Deng
D000328:Adult; D009202:Cardiomyopathies; D002311:Cardiomyopathy, Dilated / Q000378:metabolism*; D005260:Female; D006352:Heart Ventricles / Q000378:metabolism*; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D014158:Transcription, Genetic
D015850:Interleukin-6; D012333:RNA, Messenger