The effect of magnesium sulfate on the activity of matrix metalloproteinase-9 in fetal cord plasma and human umbilical vein endothelial cells.
OBJECTIVE
Clinical evidence suggests that magnesium sulfate may reduce the risk of fetal neurologic injury in preterm delivery. Matrix metalloproteinase-9 (MMP-9) levels are elevated in preterm labor patients. There is evidence that MMP-9 may break down the blood-brain barrier in humans, causing cytokine mediated cell injury. Our objective was to determine whether the addition of magnesium sulfate attenuates activity of MMP-9, a complex zinc-dependent enzyme, in fetal cord plasma.


METHODS
We collected cord plasma in 6 term, unlabored patients. Using enzyme-linked immunosorbent assay, we measured the activity of MMP-9 with varying concentrations of magnesium sulfate added in vitro. Results were verified using a human umbilical cord vein endothelial cell (HUVEC) line.


RESULTS
Addition of physiologic doses of magnesium sulfate (0.07 mg/mL) resulted in a 25% decrease in active MMP-9 (P = .03). In a HUVEC line, magnesium sulfate resulted in a 32% decrease in MMP-9 activity (P = .00012).


CONCLUSIONS
The addition of magnesium sulfate attenuated MMP-9 activity in cord plasma and in a HUVEC line.
Dolinsky
Brad M
BM
Department of Obstetrics and Gynecology, Madigan Army Medical Center, Tacoma, WA, USA.
Ippolito
Danielle L
DL
Tinnemore
Deborah
D
Stallings
Jonathan D
JD
Zelig
Craig M
CM
Napolitano
Peter G
PG
D002460:Cell Line; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005312:Fetal Blood / Q000378:metabolism*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008278:Magnesium Sulfate / Q000494:pharmacology*; D020780:Matrix Metalloproteinase 9 / Q000187:drug effects* / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D012313:RNA / Q000378:metabolism; D015149:Tocolytic Agents / Q000494:pharmacology*; D014471:Umbilical Veins / Q000166:cytology*
D015149:Tocolytic Agents; D012313:RNA; D008278:Magnesium Sulfate; D020780:Matrix Metalloproteinase 9