The arylhydrocarbon receptor (AhR), but not the AhR-nuclear translocator (ARNT), is increased in hearts of patients with cardiomyopathy.
The objective of this study was to investigate the expression of the arylhydrocarbon receptor (AhR) and its partner AhR-nuclear translocator (ARNT) in left ventricle specimens from explanted hearts from patients with cardiomyopathy (CMP). Explanted hearts from 16 patients with ischemic (n=9, age 63+/-12 years) and dilative (n=7, age 54+/-12 years) CMP, undergoing heart transplantation were examined. Healthy donor hearts from five accident victims served as controls. As these donors were of younger age (32+/-11 years), additionally, donor hearts from three older accident victims (age 48+/-15 years) without clinical symptoms but with signs of ventricular hyperthrophy (n=1) or atherosclerotic lesions (n=2) were included ("pathological controls"). Expression of AhR and ARNT was analyzed using semi-quantitative immunohistochemistry, and in selected samples, Western blot- and reverse-transcription polymerase chain reaction analysis were performed to confirm AhR and ARNT expression. Immunohistological analysis revealed weak to intermediate staining of anti-AhR in control, but weak to intense staining in CMP- and "pathologic control" specimens, indicating significantly increased AhR levels in the diseased heart. Moreover, in CMP specimens, the percentage of AhR-positive cells was strongly increased. Higher anti-AhR staining was also seen in two atherosclerotic "pathologic control" specimens. In all groups, the intensity of anti-ARNT staining was more pronounced than AhR staining, but significant differences or any age-related alterations were not observed. In conclusion, the increased cellular content of AhR in left ventricular specimens from CMP patients suggests a role for AhR in heart disease.
Mehrabi
Mohammad Reza
MR
Department of Cardiology, University of Vienna, Austria. mohammad.mehrabi@univie.ac.at
Steiner
Georg E
GE
Dellinger
Christoph
C
Kofler
Anne
A
Schaufler
Katharina
K
Tamaddon
Forouzan
F
Plesch
Karina
K
Ekmekcioglu
Cem
C
Maurer
Gerald
G
Glogar
Helmut D
HD
Thalhammer
Theresia
T
D000328:Adult; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator; D015153:Blotting, Western; D009202:Cardiomyopathies / Q000378:metabolism* / Q000473:pathology; D002452:Cell Count; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins; D005260:Female; D006352:Heart Ventricles / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D018336:Receptors, Aryl Hydrocarbon / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
C497396:ARNT protein, human; D017931:DNA Primers; D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D018336:Receptors, Aryl Hydrocarbon; D014157:Transcription Factors; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator