Expression of ferroportin1, hephaestin and ceruloplasmin in rat heart.
Iron-mediated injury plays an important role in a number of heart disorders. Studies on heart iron are therefore crucial for understanding the causes of excessive heart iron. Heart cells have the ability to accumulate transferrin-bound-iron via the transferrin receptor and non-transferrin-bound-iron probably via the L-type Ca2+ channel and the divalent metal transporter1. However, little is known about the mechanisms of iron export in the heart cells. Here, we investigated expression of iron exporters including ferroportin 1 (Fpn1), ceruloplasmin (CP) and hephaestin (Heph) and provided evidence for their existence in the heart. We demonstrated that iron has a significant effect on expression of Fpn1 and CP, but not Heph. Treatment of a high-iron diet induced a significant increase in Fpn1, a decrease in CP but no change in Heph mRNA and protein. The control of Fpn1 and CP protein expression by iron was parallel to that of their mRNA expression, suggesting a transcriptional regulation of Fpn1 and CP by iron. The existence of these proteins in the heart implies that they might have a role in heart iron homeostasis.
Qian
Zhong Ming
ZM
Laboratory of Iron Metabolism, Department of Applied Biology and Chemical Technology and National Key Laboratory of Chinese Medicine and Molecular Pharmacology (Shenzhen), Hong Kong, PR China. bczmqian@polyu.edu.hk
Chang
Yan Zhong
YZ
Leung
Gina
G
Du
Jun Rong
JR
Zhu
Li
L
Wang
Qin
Q
Niu
Lijian
L
Xu
You Jia
YJ
Yang
Lei
L
Ho
Kwok Ping
KP
Ke
Ya
Y
D000818:Animals; D001693:Biological Transport, Active; D027682:Cation Transport Proteins / Q000096:biosynthesis*; D002570:Ceruloplasmin / Q000096:biosynthesis*; D007501:Iron / Q000008:administration & dosage / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis*; D009206:Myocardium / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D011990:Receptors, Transferrin / Q000096:biosynthesis; D015533:Transcriptional Activation; D000098742:Ferroportin
D027682:Cation Transport Proteins; C492163:Heph, protein, rat; D008565:Membrane Proteins; D012333:RNA, Messenger; D011990:Receptors, Transferrin; D000098742:Ferroportin; D007501:Iron; D002570:Ceruloplasmin