Inhibitory effects of polymyxin B on NF-kappaB activation and expression of procollagen I, III in pre-eclamptic umbilical artery smooth muscle cells.
BACKGROUND
It has been identified that in patients with pre-eclampsia, several factors were released into the serum, which can regulate the proliferation of vascular smooth muscle cells and stimulate the synthesis of extracellular matrix (ECM). However, the signal transduction pathway of the growth factors and cytokines synthesized by endothelial cells leading to the proliferation and ECM synthesis of human umbilical arterial smooth muscle cell (HUASMC) is unknown. The aim of this study was to research the effects of protein kinase C (PKC) inhibitor, polymyxin B (PMB), on the proliferation, nuclear factor-kappa B (NF-kappaB) activation, and expression of procollagen I and III mRNA in HUASMC cultured with pre-eclamptic umbilical sera.


METHODS
Normal HUASMCs were treated with pre-eclamptic umbilical serum (pre-eclamptic group), pre- eclamptic umbilical serum plus PMB (PMB group), or normal umbilical serum (normal group). The expression of I-kappaB, NF-kappaB was detected by Western blotting after the HUASMC was incubated for 2 hours. The proliferation of HUASMC was evaluated by MTT, the cell cycle was analyzed by flow cytomerty, and the expression of procollagen I, III mRNA was measured by RT-PCR assay after HUASMC was incubated for 48 hours. ANOVA was used for statistical analysis.


RESULTS
Umbilical sera in pre-eclampsia could stimulate the proliferation, the DNA synthesis, the transition of G(0) + G(1) phase or G(2)/M phase to S and phase, the activation of NF-kappaB, and the expression of procollagen I mRNA of HUASMC as compared with normal umbilical sera (P < 0.01). PMB could inhibit the proliferation, the DNA synthesis, the transition of G(0) + G(1) or G(2)/M phase phase to S phase, the activation of NF-kappaB, and the expressions of procollagen I mRNA of HUASMC stimulated by umbilical sera in pre-eclampsia (P < 0.01).


CONCLUSIONS
PKC-NF-kappaB signal transduction pathway may play a key role in SMC phenotype modulation, which is more important in the pathogenesis of placental blood vessel in pre-eclampsia.
Department of Obstetrics and Gynecology, Shanghai Jiaotong University-Affiliated Sixth People's Hospital, Shanghai 200233, China. jianrzh@163.com
Rong-zhen
RZ
Jiang
Han-ping
HP
Chen
Xiao-yan
XY
Xu
D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics*; D024061:Collagen Type III / Q000235:genetics*; D005260:Female; D006801:Humans; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D016328:NF-kappa B / Q000502:physiology*; D011112:Polymyxin B / Q000494:pharmacology*; D011225:Pre-Eclampsia / Q000378:metabolism* / Q000473:pathology; D011247:Pregnancy; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D015398:Signal Transduction; D014469:Umbilical Arteries / Q000378:metabolism
D024042:Collagen Type I; D024061:Collagen Type III; D016328:NF-kappa B; D012333:RNA, Messenger; D011493:Protein Kinase C; D011112:Polymyxin B