(T1330-05-28) Prenatal E-Cigarette Use Disrupts Postnatal Blood-Brain Barrier (BBB) Integrity and Worsens Ischemic Stroke Outcomes- Implications on Brain Drug Delivery

Purpose: Electronic nicotine delivery system (ENDS), also commonly known as cigarette (e-Cig) is considered as a safer alternative to tobacco smoke and therefore has become extremely popular among all age groups and sex. Around 15% of pregnant women are now using e-Cig in the US which keeps increasing at an alarming rate. Harmful effects of tobacco smoking during pregnancy are well documented for both pregnant and postnatal health however there is lack of preclinical and clinical studies exist to evaluate the long-term effects of prenatal e-Cig exposure on postnatal health. Therefore, the aim of our study is to evaluate the effect of maternal e-Cig use on postnatal blood-brain barrier (BBB) integrity, neuroinflammation and ischemic stroke outcomes at adulthood.

Methods: In this study, pregnant CD1 mice (E5) were exposed to e‐Cig vapor (2.4% nicotine) till postnatal day (PD) 7. Weight of the offspring was measured at PD0, PD7, PD15, PD30, PD45, PD60 and PD90. The expression of structural elements of BBB, tight junction proteins (ZO-1, Claudin-5, Occludin), astrocyte (GFAP), pericyte (PDGFRβ) and basement membrane (Laminin α1, Laminin α4), neuron specific marker (NeuN), water channel protein (AQP4) and glucose transporter (GLUT1) were analyzed in both male and female offspring using western blot and immunofluorescence at PD7, PD23, PD45 and PD90. Relevant neuro-inflammatory markers were quantified at PD 7 and PD 90. Middle cerebral artery occlusion (MCAO) was performed in prenatally e-Cig exposed adult female offspring to evaluate ischemic stroke outcomes (% injury, edema ratio, neurological scores, behavioral outcomes) were evaluated by middle cerebral artery occlusion (MCAO) method in prenatally e-Cig exposed adult female offspring. Estrous cycle was recorded by vaginal cytology method.

Results: In our study, significantly reduced expression of tight junction proteins and astrocyte marker were observed in male and female offspring till PD 90 (P < 0.05). Moreover, higher level of cytokines was found in offspring brain at PD 7. Additionally, prenatally e-Cig exposed female adult offspring had worsened ischemic stroke injury and neurological score compared to control offspring (P < 0.05).

Conclusion: Our findings suggest that prenatal e-Cig exposure induces some long-term neurotoxic effects on neonates by disrupting postnatal blood-brain barrier integrity, inducing neuro-inflammation, and worsening ischemic stroke outcomes which may contribute in pathophysiology and therapeutic targets for cerebrovascular diseases.

Acknowledgements:

Funding: NIH R01DA049737 and R01DA02912
No conflict of interest.


Summary table for expression of Blood-Brain Barrier integrity markers at PD7, PD23, PD45 and PD90 in both male and female offspring.


Assessment of pro-inflammatory cytokines in offspring brain at PD7 by immunobead assay.


Evaluation of ischemic stroke outcomes by middle cerebral artery occlusion (MCAO) method.