Our previous work has shown that
nicotine suppressed
lipopolysaccharide (LPS)-induced placental
inflammation by inhibiting
cytokine release as well as infiltration of leukocytes into the placenta through the cholinergic anti-inflammatory pathway.
Nicotine also increased fetal survival and restored pup weight. In the present study, we aim to further investigate if
fetal growth restriction (FGR) occurs with LPS treatment, and evaluate the protective effects of
nicotine on fetuses in late gestation of rats. Pregnant Sprague-Dawley rats were divided into control group,
nicotine group, LPS group and LPS +
nicotine group. Rats were first pretreated with
nicotine or vehicle by
subcutaneous injection on gestation day (GD)14 and GD15, followed by LPS or vehicle
intraperitoneal injection on GD16, and were killed on GD18. Loss of fetuses, number and weights of live fetuses and weights of placentas were recorded. Placentas were collected to evaluate placental pathology and determine inflammatory
cytokines and
vascular endothelial growth factor (
VEGF) levels. We found that LPS treatment increased levels of placental inflammatory
cytokines and placental pathological damage, decreased levels of
VEGF, reduced number of live fetuses and induced FGR. Pretreatment with
nicotine reversed LPS-induced high levels of placental inflammatory
cytokines, low levels of placental
VEGF and placental pathological damage, then rescued the number and weights of live fetuses. These data demonstrated that activation of the cholinergic anti-inflammatory pathway by
nicotine protected fetus against LPS-induced FGR through ameliorating placental
inflammation and vascular development in late pregnancy in rats. It may be an alternative therapeutic strategy for
inflammation- induced FGR in late pregnancy.