The effect of nicotine on the production of soluble fms-like tyrosine kinase-1 and soluble endoglin in human umbilical vein endothelial cells and trophoblasts.
OBJECTIVE
To evaluate the effect of nicotine on the production of soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng) in human umbilical vein endothelial cells (HUVECs) and trophoblast cells, and to assess the involvement of alpha 7 nicotinic acetylcholine receptor (alpha7 nAChR) in this process.


METHODS
Commercially available full-term placental trophoblasts and HUVECs derived from the umbilical cord of a normal pregnancy were used. The expression of alpha7 nAChR was assessed by immunostaining, RT-PCR, and western blotting. The expression of sFlt-1 and sEng protein in the cell media after 6 and 24 hours of treatment with nicotine was evaluated using a commercially available ELISA. To determine the involvement of alpha7 nAChR in the nicotinic effect, cells were treated with the alpha7 nAChR antagonist alpha-bungarotoxin (alpha-BGT) prior to the nicotine exposure. Levels of significance were determined using the Student's t-test and one-way ANOVA, and a p-value < 0.05 was considered significant.


METHODS
The levels of sFlt-1 and sEng protein were evaluated before and after the nicotine treatment with or without alpha-BGT pre-treatment.


RESULTS
In trophoblast cells, a significant reduction of sFlt-1 and sEng protein was observed after 24 hours of nicotine treatment as compared to the untreated group (p = 0.002, 0.000). In HUVECs, nicotine only had a suppressive effect on the expression of sEng at 6 hours (p = 0.03); there was no effect on sFlt-1 expression. However, pre-treatment with alpha-BGT did not reverse the nicotine-induced suppressive effect on the expression of sFlt-1 and sEng in trophoblasts and HUVECs.


CONCLUSIONS
Nicotine reduced the production of sFlt-1 and sEng in trophoblasts and sEng in HUVECs. This effect was not mediated by alpha7 nAChR.
Kwon
Ja-Young
JY
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Korea.
Bai
Sang-Wook
SW
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Korea.
Kwon
Young-Guen
YG
Department of Biochemistry, Yonsei University, Seoul, Korea.
Kim
Se-Hoon
SH
Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
Kim
Chul Hoon
CH
Department of Pharmacology, Yonsei University College of Medicine, Seoul, Korea.
Kang
Moung Hwa
MH
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Korea.
Linton
John A
JA
Department of Family Medicine, Yonsei University College of Medicine, Seoul, Korea.
Park
Yong-Won
YW
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Korea.
D015703:Antigens, CD / Q000378:metabolism*; D002038:Bungarotoxins / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D000071063:Endoglin; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005731:Ganglionic Stimulants / Q000494:pharmacology*; D006801:Humans; D009538:Nicotine / Q000494:pharmacology*; D011247:Pregnancy; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011978:Receptors, Nicotinic / Q000378:metabolism; D013997:Time Factors; D014327:Trophoblasts / Q000187:drug effects / Q000378:metabolism*; D014471:Umbilical Veins / Q000166:cytology*; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000378:metabolism*; D064569:alpha7 Nicotinic Acetylcholine Receptor
D015703:Antigens, CD; D002038:Bungarotoxins; C579167:Chrna7 protein, human; C064206:ENG protein, human; D000071063:Endoglin; D005731:Ganglionic Stimulants; D011956:Receptors, Cell Surface; D011978:Receptors, Nicotinic; D064569:alpha7 Nicotinic Acetylcholine Receptor; D009538:Nicotine; C501162:FLT1 protein, human; D040281:Vascular Endothelial Growth Factor Receptor-1