Endogenous agmatine inhibits cerebral vascular matrix metalloproteinases expression by regulating activating transcription factor 3 and endothelial nitric oxide synthesis.
Earlier investigations from our laboratory demonstrated that the expression of matrix metalloproteinases (MMPs) was down-regulated by exogenously administered agmatine against ischemia-like injuries in the murine brain capillary endothelial (bEnd.3) cells. In our present study, we intended to investigate the mechanism involved in the inhibition of MMPs in bEnd.3 cells infected with retroviral containing human arginine decarboxylase (hADC) gene which can synthesize agmatine endogenously (ADCDeltabEnd.3 cells). The ADCDeltabEnd.3 cells were subjected to oxygen glucose deprivation (OGD, 6 hrs) with reperfusion (18 hrs). High performance liquid chromatography (HPLC) analysis revealed the high levels of agmatine in the ADCDeltabEnd.3 cells compared to other experimental groups. The results demonstrated significant decrease in cell death and increase in the nitric oxide (NO) production in the ADCDeltabEnd.3 cells. The increased expression of MMP-2 and MMP-9, and decreased expression of endothelial nitric oxide synthase (eNOS) by ischemic injury was attenuated in ADCDeltabEnd.3 cells. Moreover, the expression of activating transcription factor 3 (ATF3) was increased significantly in ADCDeltabEnd.3 cells. In addition, the suppression of the MMP-2 and MMP-9 expression in ADCDeltabEnd.3 cells was prevented with ATF3 small interfering RNA (siRNA) treatment. These results suggest that the endogenous agmatine in ADCDeltabEnd.3 cells inhibits the MMPs expression mediated via the regulation of eNOS, NO and ATF3.
Jung
Hyun Joo
HJ
BK 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
Yang
Mei Zi
MZ
Kwon
Ki Hyo
KH
Yenari
Midori A
MA
Choi
Yoon Jung
YJ
Lee
Won Taek
WT
Park
Kyung Ah
KA
Lee
Jong Eun
JE
D051700:Activating Transcription Factor 3 / Q000235:genetics / Q000378:metabolism*; D000376:Agmatine / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000098:blood supply / Q000378:metabolism*; D002460:Cell Line; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D004730:Endothelium, Vascular / Q000378:metabolism*; D007150:Immunohistochemistry; D020782:Matrix Metalloproteinases / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D009569:Nitric Oxide / Q000096:biosynthesis* / Q000235:genetics; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection
D051700:Activating Transcription Factor 3; D009569:Nitric Oxide; D000376:Agmatine; D052250:Nitric Oxide Synthase Type III; D020782:Matrix Metalloproteinases