Post on 28-Mar-2021
Effects of Adolescent Cannabinoid and Nicotine Exposure
Christie Fowler, PhDAssistant Professor
Department of Neurobiology and BehaviorUniversity of California, Irvine
cdfowler@uci.edu
Disclosures
I have no competing interests to disclose.
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Tobacco and Nicotine Addiction
• 6 million premature deaths each year worldwide
• 600,000 deaths second-hand exposure in non-smokers
• Quitting success rate <10% after 1 year• Main psychoactive component in
tobacco: Nicotine
E-Cigarettes and Adolescence
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Chadwick et al., Frontiers in Psychiatry, 2013
High Comorbidity of Nicotine and Cannabis Co-use
Cannabis Exposure During Development
A natural and safe herb? Are there limitations to
this characterization?
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112019 North American Cannabis Summit
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www.the-scientist.com
Drugs and the Brain
How do cannabinoids and nicotine act to
modulate function of the brain?
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THC and CBD act on
cannabinoid receptors in
the brain
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Nicotine acts on
nicotinic receptors
in the brain
16Jasinska et al. 2013 Neuropharmacology
Research Question
Is adolescence a sensitive period for the
detrimental effects of drug exposure?
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Chadwick et al., Frontiers in Psychiatry, 2013
Dynamic changes in endogenous cannabinoid signaling during adolescence
Human and rodent development
2019 North American Cannabis Summit 19Yuan et al., J Physiology, 2015
Adolescent Drug Exposure Paradigm
2019 North American Cannabis Summit 20Yuan et al., J Physiology, 2015
PND 38 39 40 41 42 43 44 45 46 47 48 49 70
ControlNIC – NicotineWIN – Cannabinoid receptor agonistNIC/WIN – Nicotine and WIN co-exposure
Cannabinoid exposure in females, but not male, decreases body weight in adolescence
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Research Question
Does adolescent nicotine and/or cannabinoid exposure alter the ability to learn an operant task
in adulthood?
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Adolescent drug exposure does not alter operant learning for food reward in males
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Adolescent drug exposure does not alter operant learning for food reward in females
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Enhanced cognitive flexibility in the reversal task in cannabinoid-exposed males
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Male Female
Research Question
Does adolescent nicotine and/or cannabinoid exposure alter affective behaviors?
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Decreased anxiety-associated behaviors in males, but not females, during adulthood
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Increased sucrose reward exhibited in cannabinoid exposed males, and an opposing effect in females
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Male Female
Group differences not found in a measure of depression
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Male Female
Research Question
Do the reward-related effects predispose groups to altered nicotine reinforcement in adulthood?
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Increased nicotine intake found in cannabinoid-exposed males, whereas decreased intake found in females
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Male Female
Summary
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In males, long-lasting effects of adolescent cannabinoid exposurelead to decreased anxiety-like behaviors, increased reward-related cognitive flexibility, and increased nicotine intake duringadulthood.
Female mice exhibited differential effects than males, withcannabinoid treatment leading to decreased weight gain duringadolescence, and decreased natural reward consumption andnicotine intake during adulthood.
Together, these data provide evidence of long-term effects ofcannabinoid exposure on later affective, cognitive and nicotinetaking behaviors in adulthood.
NIH K99/R00 DA-032543NIH DP1 DA-039658
Fowler LabValeria Lallai, PhDYasmine SherafatAngeline EugeneYen-Chu (Andrew) ChenJP FowlerAmina AhmedAndres Staben RamirezMalia BautistaEashan KothaAdriana Hernandez VasquezMiguel Ruiz RomoRachel Meek
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