Skip to main content

Main menu

  • HOME
  • CONTENT
    • Early Release
    • Featured
    • Current Issue
    • Issue Archive
    • Blog
    • Collections
    • Podcast
  • TOPICS
    • Cognition and Behavior
    • Development
    • Disorders of the Nervous System
    • History, Teaching and Public Awareness
    • Integrative Systems
    • Neuronal Excitability
    • Novel Tools and Methods
    • Sensory and Motor Systems
  • ALERTS
  • FOR AUTHORS
  • ABOUT
    • Overview
    • Editorial Board
    • For the Media
    • Privacy Policy
    • Contact Us
    • Feedback
  • SUBMIT

User menu

Search

  • Advanced search
eNeuro

eNeuro

Advanced Search

 

  • HOME
  • CONTENT
    • Early Release
    • Featured
    • Current Issue
    • Issue Archive
    • Blog
    • Collections
    • Podcast
  • TOPICS
    • Cognition and Behavior
    • Development
    • Disorders of the Nervous System
    • History, Teaching and Public Awareness
    • Integrative Systems
    • Neuronal Excitability
    • Novel Tools and Methods
    • Sensory and Motor Systems
  • ALERTS
  • FOR AUTHORS
  • ABOUT
    • Overview
    • Editorial Board
    • For the Media
    • Privacy Policy
    • Contact Us
    • Feedback
  • SUBMIT
PreviousNext
Research ArticleResearch Article: New Research, Disorders of the Nervous System

Green Apple e-Cigarette Flavorant Farnesene Triggers Reward-Related Behavior by Promoting High-Sensitivity nAChRs in the Ventral Tegmental Area

Skylar Y. Cooper, Austin T. Akers and Brandon J. Henderson
eNeuro 3 August 2020, 7 (4) ENEURO.0172-20.2020; DOI: https://doi.org/10.1523/ENEURO.0172-20.2020
Skylar Y. Cooper
Department of Biomedical Sciences, Marshall University, Joan C Edwards School of Medicine, Huntington, WV 25703
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • ORCID record for Skylar Y. Cooper
Austin T. Akers
Department of Biomedical Sciences, Marshall University, Joan C Edwards School of Medicine, Huntington, WV 25703
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Brandon J. Henderson
Department of Biomedical Sciences, Marshall University, Joan C Edwards School of Medicine, Huntington, WV 25703
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • ORCID record for Brandon J. Henderson
  • Article
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF
Loading

Article Figures & Data

Figures

  • Tables
  • Figure 1.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Figure 1.

    Farnesene-alone produces reward-related behavior in male and female mice. A1,2, Male and female mice were administered saline or farnesene at doses of 0.1, 1.0, or 10 mg/kg in a CPP assay. B1,2, Male and female mice were administered saline or 0.1 mg/kg farnesene in an open field locomotor assay. All data are mean ± SEM; *p < 0.05, **p < 0.01, ****p < 0.0001; one-way ANOVA with post hoc Tukey (A) or unpaired t test (B). Exact p values are given in Results. Number of mice for each treatment group in CPP assays is indicated in parenthesis. Dots within bars represent the CPP scores or locomotor activity from individual mice within the designated treatment groups.

  • Figure 2.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Figure 2.

    Farnesene (0.1 mg/kg) enhances nicotine reward-related behavior in both sexes. A, B, Male and female mice were administered saline, nicotine (0.5 mg/kg), or nicotine (0.5 mg/kg) plus farnesene (0.1 mg/kg) in a CPP assay. All data are mean ± SEM; *p < 0.05, **p < 0.01, ***p < 0.005; one-way ANOVA with post hoc Tukey. Exact p values are given in Results. Number of mice for each treatment group is indicated in parenthesis, and dots within bars represent the CPP scores from individual mice within the designated treatment group.

  • Figure 3.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Figure 3.

    Farnesene treatment has no effect on nAChR number in the midbrain. A1, Schematic of target mouse brain region (bregma −3.1 mm). A2, Sample 10× image of a mouse coronal brain section at approximately bregma −3.1 mm. Scale bar, 250 μm. B, Sample images of saline and farnesene treated VTA dopamine neurons. Scale bar, 15 μm. C, D, RID of α4*, α6*, and α4α6* nAChRs of VTA dopamine neurons (C1, D1), α4* nAChRs of VTA GABA neurons (C2, D2), and α4* nAChRs of SNr GABA neurons (C3, D3) in saline-treated and farnesene-treated (0.1 mg/kg) male (C) and female (D) mice. All data are mean ± SEM. Unpaired t test. Dots indicate the RID values from individual mice.

  • Figure 4.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Figure 4.

    Farnesene alters the stoichiometry of α4α6β2* nAChRs in VTA DA neurons. Mean NFRET percentage (A1, B1,), mean NFRET pixel count (A2, B2), and mean pixels/neuron histograms (A3, B3) for saline-treated and farnesene-treated (0.1 mg/kg) VTA dopamine neurons in male (A) and female (B) mice. All data are mean ± SEM; *p < 0.05; unpaired t test. Exact p values are given in Results. Dots within bars represent the values from individual mice within the designated treatment group; n > 40 neurons per mouse per treatment group.

  • Figure 5.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Figure 5.

    Farnesene favors high-sensitivity nAChRs in neuro-2a cells. Representative neuro-2a cells transfected with α4-mCherry, α4-GFP or α6-GFP, and β2wt nAChR subunits to produce (A) α4-mCherryα6-GFPβ2 nAChRs or (C) α4-mCherryα4-GFPβ2 nAChRs. Scale bar, 10 μm. Mean NFRET pixel count (B1, D1) and NFRET percentage (B2, D2) treated as control or with 0.5 μm farnesene for (A) α4-mCherryα6-GFPβ2 nAChRs or (C) α4-mCherryα4-GFPβ2 nAChRs. All data are mean ± SEM; *p < 0.05, ****p < 0.001; unpaired t test. Exact p values are given in Results. Dots within bars represent the values from individual cells within the designated treatment group; n > 30 cells per condition.

  • Figure 6.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Figure 6.

    Farnesene favors high-sensitivity nAChRs in neuro-2a cells. A, α4β2 nAChRs assemble in two stoichiometries, and we observed that farnesene treatment shifts a mixed population of HS and LS α4β2 nAChRs to a majority of HS α4β2 nAChRs. B, In examining α4α6β2 nAChRs, under control treatments, ∼65% of the population are α4α6β2 nAChRs while the remainder is likely α4β2 nAChRs. Following treatment with farnesene, <14% of the nAChRs are α4α6β2 nAChRs.

  • Figure 7.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Figure 7.

    Farnesene enhances the affinity and potency of nicotine. Representative images of VTA pDA neurons in a brain slice (bregma −3.1) were identified through the presence of α6-GFP nAChRs in IR-DIC (A1) and GFP fluorescence (A2) imaging modes. Scale bars, 20 μm. B, Representative inward currents from VTA pDA neurons (α6-GFP-positive) with 10-s applications of 500 nm (B1) or 10 μm (B2) nicotine in voltage-clamp mode. Arrows indicate start of nicotine puff application and dotted red lines indicate baseline before puff and the duration of nicotine application. C, Average nicotine concentration response of peak-current amplitude of VTA pDA neurons (n = 7 neurons/4 mice and 5 neurons/3 mice per nicotine concentration for saline-treated and farnesene-treated mice, respectively). D, Representative waveforms of sEPSCs from VTA pDA neurons recorded from saline-treated or farnesene-treated mice in the presence of 30 μm picrotoxin. E, Mean sEPSC frequency (E1) and amplitude (E2) in saline-treated and farnesene-treated mouse brain slices (n = 9 neurons/4 mice and 9 neurons/3 mice for saline-treated and farnesene-treated mice, respectively). For all assays, drug treatments were consistent with the CPP assay paradigm using 0.1 mg/kg farnesene. C, EI,2, Data are mean ± SEM *p < 0.05, ****p < 0.0001; unpaired t test. Exact p values are given in Results. Dots within bars represent the values from individual neurons within the designated treatment group.

  • Figure 8.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Figure 8.

    Farnesene acts as a partial agonist on nAChRs. A, B, Voltage-clamp recordings from putative VTA dopamine neurons. A, Five and 500 μm farnesene and 100 μm nicotine were applied to putative VTA dopamine neurons. The β2* nAChR antagonist, DhβE (0.3 μm) blocked inward currents stimulated by 500 μm farnesene. B, Mean peak current amplitude for farnesene and nicotine applications on pDA neurons in the VTA. C–E, Voltage-clamp recordings from neuro-2a cells transiently transfected to contain α4-GFPβ2 and α6-GFPβ2β3 nAChRs. C, Representative images of neuro-2a cells that contain α4-GFPβ2 or α6-GFPβ2β3 nAChRs. D, Representative inward currents stimulated by 300-ms applications of 500 μm farnesene on neuro-2a cells containing α4-GFPβ2 or α6-GFPβ2β3 nAChRs. E1,2, Mean peak current amplitude of 500 μm farnesene and nicotine applications (3 and 100 μm nicotine for α6-GFPβ2β3 and α4-GFPβ2 nAChRs, respectively) on neuro-2a cells containing nAChRs. B, E1,2, Data are mean ± SEM; **p < 0.01, ****p < 0.0001; one-way ANOVA with post hoc Tukey (B) or unpaired t test (E). Dots represent data from individual neurons or cells. Exact p values are given in Results.

Tables

  • Figures
    • View popup
    Table 1

    Statistical tests and results

    FigureType of testInteraction/main effectStatistical data
    1, 2 Two-way
    ANOVA
    Sex × drugF(5,88) = 3.045, p = 0.0140
    1, 2 Two-way ANOVASexF(1,88) = 10.55, p = 0.0016
    1, 2 Two-way ANOVADrugF(5,88) = 12.21, p < 0.0001
    1A1 One-way ANOVAF(3,30) = 5.98, p = 0.0025
    1A1 Post hoc
    Tukey
    Saline vs 0.1 mg/kg; p = 0.0065
    1A1 Post hoc
    Tukey
    Saline vs 1.0 mg/kg; p = 0.9997
    1A1 Post hoc
    Tukey
    Saline vs 10 mg/kg; p = 0.9770
    1A1 Post hoc
    Tukey
    0.1 vs 1.0 mg/kg; p = 0.0203
    1A1 Post hoc
    Tukey
    0.1 vs 10 mg/kg; p = 0.0047
    1A1 Post hoc
    Tukey
    1.0 vs 10 mg/kg; p = 0.9680
    1A2 One-way ANOVAF(3,25) = 9.81, p = 0.0002
    1A2 Post hoc
    Tukey
    Saline vs 0.1 mg/kg; p < 0.0001
    1A2 Post hoc
    Tukey
    Saline vs 1.0 mg/kg; p = 0.0126
    1A2 Post hoc
    Tukey
    Saline vs 10 mg/kg; p = 0.0402
    1A2 Post hoc
    Tukey
    0.1 vs 1.0 mg/kg; p = 0.4631
    1A2 Post hoc
    Tukey
    0.1 vs 10 mg/kg; p = 0.2245
    1A2 Post hoc
    Tukey
    1.0 vs 10 mg/kg; p = 0.9669
    1B1 Unpaired
    t test
    Saline vs farnesene (males), p = 0.111
    1B2 Unpaired
    t test
    Saline vs farnesene (females), p = 0.801
    2A One-way ANOVAF(2,23) = 8.506, p = 0.0017
    2A Post hoc
    Tukey
    Saline vs nicotine; p = 0.0173
    2A Post hoc
    Tukey
    Saline vs nicotine + farnesene; p = 0.0022
    2A Post hoc
    Tukey
    Nicotine vs nicotine + farnesene; p = 0.4280
    2B One-way ANOVAF(2,25) = 13.04, p = 0.0001
    2B Post hoc
    Tukey
    Saline vs nicotine; p = 0.2916
    2B Post hoc
    Tukey
    Saline vs nicotine + farnesene; p = 0.0001
    2B Post hoc
    Tukey
    Nicotine vs nicotine + farnesene; p = 0.0041
    3C1 Unpaired
    t test
    [α4, p = 0.2239], [α6, p = 0.9065], [α4α6, p = 0.6259]
    3C2 Unpaired
    t test
    p = 0.1268
    3C3 Unpaired
    t test
    p = 0.1227
    3D1 Unpaired
    t test
    [α4, p = 0.0515], [α6, p = 0.4842], [α4α6, p = 0.0653]
    3D2 Unpaired
    t test
    p = 0.5572
    3D3 Unpaired
    t test
    p = 0.6156
    4A1 Unpaired
    t test
    p = 0.6343
    4A2 Unpaired
    t test
    p = 0.7225
    4B1 Unpaired
    t test
    p = 0.5285
    4B2 Unpaired
    t test
    p = 0.0480
    5B1 Unpaired
    t test
    p < 0.0001
    5B2 Unpaired
    t test
    p < 0.0001
    5D1 Unpaired
    t test
    p = 0.0149
    5D2 Unpaired
    t test
    p < 0.0001
    7E1 Unpaired
    t test
    p = 0.0002
    7E2 Unpaired
    t test
    p < 0.0001
    8B One-way ANOVAF(2,12) = 23.05, p < 0.0001
    8B Post hoc
    Tukey
    5 μm farnesene vs 500 μm farnesene; p = 0.1823
    8B Post hoc
    Tukey
    5 μm farnesene vs 100 μm nicotine; p < 0.0001
    8B Post hoc
    Tukey
    500 μm farnesene vs 100 μm nicotine, p = 0.0031
    8E1 Unpaired
    t test
    p < 0.0001
    8E2 Unpaired
    t test
    p < 0.0001
    • View popup
    Table 2

    G*Power statistics, CPP ( Figs. 1, 2)

    Input parametersOutput parameters
    Test familyF testsNoncentrality parameter16.94
    Test typeANOVA: one-wayCritical F2.21
    Type of analysisA prioriNumerator df7
    Effect size0.55Denominator df48
    α err prob0.05Total sample size56
    Power0.8Sample size/group7
    Number of groups8Actual Power0.811
    • Sample size indicates number of mice needed per treatment group.

    • View popup
    Table 3

    G*Power statistics, locomotor behavior (Fig. 1B1,2 )

    Input parametersOutput parameters
    Test familyt tests (two tails)Noncentrality parameter3.21
    Test typeBiserial modelCritical t2.23
    Type of analysisA prioridf10
    Effect size0.68Total sample size12
    α err prob0.05Sample size/group6
    Power0.8Actual power0.825
    Number of groups2
    • Sample size indicates the number of neurons/cells needed for sufficient power.

    • View popup
    Table 4

    G*Power statistics, fluorescence microscopy ( Figs. 3, 4)

    Input parametersOutput parameters
    Test familyt tests (two tails)Noncentrality parameter3.53
    Test typeBiserial modelCritical t2.57
    Type of analysisA prioridf5
    Effect size0.8Total sample size7
    α err prob0.05Sample size/group≥3
    Power0.8Actual Power0.803
    Number of groups2
    • Sample size indicates number of mice needed per treatment group.

    • View popup
    Table 5

    G*Power statistics, brain slice electrophysiology (sEPSCs; Fig. 7)

    Input parametersOutput parameters
    Test familyt tests (two tails)Noncentrality parameter3.25
    Test typeBiserial modelCritical t2.26
    Type of analysisA prioridf9
    Effect size0.7Total sample size11
    α err prob0.05Sample size/group6–7
    Power0.8Actual Power0.823
    Number of groups2
    • Sample size indicates the number of neurons needed for sufficient power.

    • View popup
    Table 6

    G*Power statistics, electrophysiology (inward currents; Fig. 8)

    Input parametersOutput parameters
    Test familyt tests (two tails)Noncentrality parameter3.40
    Test typeBiserial modelCritical t2.36
    Type of analysisA prioridf7
    Effect size0.75Total sample size9
    α err prob0.05Sample size/group≥5
    Power0.8Actual Power0.830
    Number of groups2
    • Sample size indicates the number of neurons/cells needed for sufficient power.

Back to top

In this issue

eneuro: 7 (4)
eNeuro
Vol. 7, Issue 4
July/August 2020
  • Table of Contents
  • Index by author
  • Ed Board (PDF)
Email

Thank you for sharing this eNeuro article.

NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. We do not retain these email addresses.

Enter multiple addresses on separate lines or separate them with commas.
Green Apple e-Cigarette Flavorant Farnesene Triggers Reward-Related Behavior by Promoting High-Sensitivity nAChRs in the Ventral Tegmental Area
(Your Name) has forwarded a page to you from eNeuro
(Your Name) thought you would be interested in this article in eNeuro.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Print
View Full Page PDF
Citation Tools
Green Apple e-Cigarette Flavorant Farnesene Triggers Reward-Related Behavior by Promoting High-Sensitivity nAChRs in the Ventral Tegmental Area
Skylar Y. Cooper, Austin T. Akers, Brandon J. Henderson
eNeuro 3 August 2020, 7 (4) ENEURO.0172-20.2020; DOI: 10.1523/ENEURO.0172-20.2020

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Respond to this article
Share
Green Apple e-Cigarette Flavorant Farnesene Triggers Reward-Related Behavior by Promoting High-Sensitivity nAChRs in the Ventral Tegmental Area
Skylar Y. Cooper, Austin T. Akers, Brandon J. Henderson
eNeuro 3 August 2020, 7 (4) ENEURO.0172-20.2020; DOI: 10.1523/ENEURO.0172-20.2020
del.icio.us logo Digg logo Reddit logo Twitter logo Facebook logo Google logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
    • Abstract
    • Significance Statement
    • Introduction
    • Materials and Methods
    • Results
    • Discussion
    • Footnotes
    • References
    • Synthesis
    • Author Response
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF

Keywords

  • electrophysiology
  • flavorants
  • microscopy
  • nicotinic receptors
  • reward-related behavior

Responses to this article

Respond to this article

Jump to comment:

No eLetters have been published for this article.

Related Articles

Cited By...

More in this TOC Section

Research Article: New Research

  • Opponent Learning with Different Representations in the Cortico-Basal Ganglia Circuits
  • Nonspiking Interneurons in the Drosophila Antennal Lobe Exhibit Spatially Restricted Activity
  • Pattern of Driver-Like Input onto Neurons of the Mouse Ventral Lateral Geniculate Nucleus
Show more Research Article: New Research

Disorders of the Nervous System

  • Brain FNDC5/irisin expression in patients and mouse models of major depression
  • Increased physiological GDNF levels have no effect on dopamine neuron protection and restoration in a proteasome inhibition mouse model of Parkinson's disease
  • Microglial Expression of the Wnt Signaling Modulator DKK2 Differs between Human Alzheimer’s Disease Brains and Mouse Neurodegeneration Models
Show more Disorders of the Nervous System

Subjects

  • Disorders of the Nervous System

  • Home
  • Alerts
  • Visit Society for Neuroscience on Facebook
  • Follow Society for Neuroscience on Twitter
  • Follow Society for Neuroscience on LinkedIn
  • Visit Society for Neuroscience on Youtube
  • Follow our RSS feeds

Content

  • Early Release
  • Current Issue
  • Latest Articles
  • Issue Archive
  • Blog
  • Browse by Topic

Information

  • For Authors
  • For the Media

About

  • About the Journal
  • Editorial Board
  • Privacy Policy
  • Contact
  • Feedback
(eNeuro logo)
(SfN logo)

Copyright © 2023 by the Society for Neuroscience.
eNeuro eISSN: 2373-2822

The ideas and opinions expressed in eNeuro do not necessarily reflect those of SfN or the eNeuro Editorial Board. Publication of an advertisement or other product mention in eNeuro should not be construed as an endorsement of the manufacturer’s claims. SfN does not assume any responsibility for any injury and/or damage to persons or property arising from or related to any use of any material contained in eNeuro.