Involvement of Rho-associated protein kinase (ROCK) and bone morphogenetic protein-binding endothelial cell precursor-derived regulator (BMPER) in high glucose-increased alkaline phosphatase expression and activity in human coronary artery smooth muscle cells.
BACKGROUND
Vascular calcification is an independent risk factor for cardiovascular disease. Diabetes mellitus increases the incidence of vascular calcification; however, detailed molecular mechanisms of vascular calcification in diabetes mellitus remain unknown. We recently reported that bone morphogenetic protein-binding endothelial cell precursor-derived regulator (BMPER) regulates osteoblast-like trans-differentiation of human coronary artery smooth muscle cells (HCASMCs).


METHODS
We investigated the effect of a hydroxymethylglutaryl-coenzyme A reductase inhibitor (statin), commonly used in patients with atherosclerotic diseases and diabetes mellitus, on alkaline phosphatase (ALP) mRNA expression in aortas of streptozotocin-induced diabetic mice. We also investigated the effects of the statin, Rho-associated protein kinase (ROCK) inhibitors and BMPER knockdown on ALP mRNA expression and activity in HCASMCs cultured in high glucose-containing media.


RESULTS
Alkaline phosphatase mRNA expression was increased in aortas of streptozotocin-induced diabetic mice, and the increase was inhibited by rosuvastatin. ALP mRNA expression and activity were increased in HCASMCs cultured in high glucose-containing media, and the increases were suppressed by rosuvastatin. This suppression was reversed by the addition of mevalonate or geranylgeranyl pyrophosphate, but not farnesyl pyrophosphate. High glucose-increased ALP mRNA expression and activity were suppressed by ROCK inhibitors. Moreover, BMPER mRNA expression was increased in diabetic mouse aortas and in HCASMCs cultured in high glucose-containing media, but was not inhibited by rosuvastatin or ROCK inhibitors. Knockdown of BMPER suppressed high glucose-increased ALP activity, but not ROCK activity in HCASMCs.


CONCLUSIONS
There are at least two independent pathways in high glucose-induced ALP activation in HCASMCs: the Rho-ROCK signaling pathway and the BMPER-dependent pathway.
Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan. yuyaterao0103@yahoo.co.jp.
Yuya
Y
Terao
Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan. seimik@med.kobe-u.ac.jp.
Seimi
S
Satomi-Kobayashi
Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan. hiratak@med.kobe-u.ac.jp.
Ken-ichi
K
Hirata
Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan. rikitake@med.kobe-u.ac.jp.|Division of Signal Transduction, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan. rikitake@med.kobe-u.ac.jp.
Yoshiyuki
Y
Rikitake
D000469:Alkaline Phosphatase / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D003331:Coronary Vessels / Q000201:enzymology / Q000473:pathology; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D003922:Diabetes Mellitus, Type 1 / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D055785:Gene Knockdown Techniques; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology; D008297:Male; D008810:Mice, Inbred C57BL; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection; D015854:Up-Regulation; D061205:Vascular Calcification / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
C476724:BMPER protein, human; D002352:Carrier Proteins; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger; C517553:crossveinless 2 protein, mouse; D054460:rho-Associated Kinases; D000469:Alkaline Phosphatase; D005947:Glucose