Effects of Chronic Inhalation of Electronic Cigarette Vapor Containing Nicotine on Neurobehaviors and Pre/Postsynaptic Neuron Markers

Abstract

Nicotine-exposed animal models exhibit neurobehavioral changes linked to impaired synaptic plasticity. Previous studies highlighted alterations in neurotransmitter levels following nicotine exposure. Vesicular glutamate transporter (VGLUT1) and vesicular gamma-aminobutyric acid (GABA) transporter (VGAT) are essential for the transport and release of glutamate and GABA, respectively, from presynaptic neurons into synapses. In our work, an e-cigarette device was used to deliver vapor containing nicotine to C57BL/6J mice for four weeks. Novel object recognition, locomotion, and Y-maze tests were performed to investigate the behavioral parameters. Protein studies were conducted to study the hippocampal expression of VGLUT1, VGAT, and postsynaptic density protein 95 (PSD95) as well as brain cytokine markers. Long-term memory and locomotion tests revealed that e-cigarette aerosols containing nicotine modulated recognition memory and motor behaviors. We found that vapor exposure increased VGLUT1 expression and decreased VGAT expression in the hippocampus. No alterations were found in PSD95 expression. We observed that vapor-containing nicotine exposure altered certain brain cytokines such as IFNβ-1 and MCP-5. Our work provides evidence of an association between neurobehavioral changes and altered hippocampal VGLUT1 and VGAT expression in mice exposed to e-cigarette vapors containing nicotine. Such exposure was also associated with altered neurobehaviors, which might affect neurodegenerative diseases.

A paradoxical switch: the implications of excitatory GABAergic signaling in neurological disorders

“…It is also critical to discuss that while chloride dyshomeostasis could be the predominant cause of excitatory GABAergic signaling in disorders, reductions in transsynaptic GABAergic signaling should also be considered a potential factor. While the data presented in this review outlined the contributions of downregulated GABA signaling towards stress-induced excitatory GABA A R-mediated responses, reductions in GABAergic signaling are also present in Alzheimer’s disease ( 179 ), ASD ( 100 , 180 ), SUD ( 181 , 182 ). It can be hypothesized that repurposing therapeutics that enhance endogenous levels of GABA could therefore alleviate excitatory GABA A R signaling throughout various disorders.…”

Nicotine inhalant via E‐cigarette facilitates sensorimotor function recovery by upregulating neuronal BDNF–TrkB signalling in traumatic brain injury

“…The E-liquid vehicle contains 70% Vegetable Glycerin and 30% Propylene Glycol. Nicotine (#N3876, ≥99% [GC], Sigma-Aldrich, Burlington, USA), is added to the vehicle solution to achieve a concentration of 24 mgÁml À1 (Alasmari et al, 2022). A paired Baby V2 S2 0.15 Ohm coil is used to create clouds of vape smoke.…”

Zebrafish (Danio rerio) as a Model for the Study of Developmental and Cardiovascular Toxicity of Electronic Cigarettes

“…Both Zebrafish and human studies have reported neurobehavioral effects following e-cigarette exposure. Zebrafish exposed to e-cigarette aerosols altered locomotor activity and anxiety-like behaviors [ 59 , 126 , 132 , 133 , 134 , 135 ], similar to human behavioral changes [ 136 , 137 ].…”