tailieunhanh - Báo cáo khoa học: Hypoxia reduces the expression of heme oxygenase-2 in various types of human cell lines A possible strategy for the maintenance of intracellular heme level

Heme oxygenase consists of two structurally related isozymes, heme oxyge-nase-1 and and heme oxygenase-2, each of which cleaves heme to form bili-verdin, iron and carbon monoxide. Expression of heme oxygenase-1 is increased or decreased depending on cellular microenvironments, whereas lit-tle is known about the regulation of heme oxygenase-2 expression. | iFEBS Journal Hypoxia reduces the expression of heme oxygenase-2 in various types of human cell lines A possible strategy for the maintenance of intracellular heme level Yongzhao Zhang1 Kazumichi Furuyama1 Kiriko Kaneko1 Yuanying Ding1 Kazuhiro Ogawa2 Miki Yoshizawa1 Masaki Kawamura1 Kazuhisa Takeda1 Tadashi Yoshida3 and Shigeki Shibahara1 1 Department of Molecular Biology and Applied Physiology Tohoku University Schoolof Medicine Sendai Japan 2 Department of Molecular Pharmacology Tohoku University Schoolof Medicine Sendai Japan 3 Department of Biochemistry Yamagata University Schoolof Medicine Yamagata Japan Keywords erythroid cells heme oxygenase-1 heme oxygenase-2 hemoglobin hypoxia Correspondence S. Shibahara Department of Molecular Biology and Applied Physiology Tohoku University Schoolof Medicine 2-1 Seiryo-machi Aoba-ku Sendai Miyagi 980-8575 Japan Fax 81 22 717 8118 Tel 81 22 717 8117 E-mail shibahar@ Present address Department of Molecular Pharmacology Kanazawa University Graduate Schoolof MedicalScience Kanazawa Japan Received 26 January 2006 revised 5 May 2006 accepted 15 May 2006 doi Heme oxygenase consists of two structurally related isozymes heme oxyge-nase-1 and and heme oxygenase-2 each of which cleaves heme to form biliverdin iron and carbon monoxide. Expression of heme oxygenase-1 is increased or decreased depending on cellular microenvironments whereas little is known about the regulation of heme oxygenase-2 expression. Here we show that hypoxia 1 oxygen reduces the expression levels of heme oxyge-nase-2 mRNA and protein after 48 h of incubation in human cell lines including Jurkat T-lymphocytes YN-1 and K562 erythroleukemia HeLa cervical cancer and HepG2 hepatoma as judged by northern blot and western blot analyses. In contrast the expression level of heme oxygenase-1 mRNA varies under hypoxia depending on the cell line it was increased in YN-1 cells decreased in HeLa and HepG2 cells and .