Chronic perinatal odour exposure with heptaldehyde affects odour sensitivity and olfactory system homeostasis in...

Area of Science:

• Neuroscience
• Olfactory System Development
• Sensory Biology

Background:

• Prenatal and early nursing odorant exposure significantly shapes olfactory circuitry development in pups.
• This can lead to lasting changes in olfactory sensitivity and preferences for experienced odors.
• Factors like odorant type, concentration, and timing influence these developmental effects.

Purpose of the Study:

• To investigate the impact of perinatal heptaldehyde exposure on olfactory receptor Olfr2 circuitry, sensitivity, and odor preferences in preweaning mice.
• To understand the neuro-anatomical and behavioral consequences of early odorant exposure.

Main Methods:

• Utilized mI7-IRES-tau-green fluorescent protein mice for tracking olfactory circuitry.
• Administered heptaldehyde exposure to dams via feed during the perinatal period.
• Assessed olfactory receptor neuron responses, gene expression in the olfactory epithelium, and glomeruli counts.
• Evaluated olfactory behaviors and preferences in pups at weaning.

Main Results:

• Perinatal heptaldehyde exposure reduced pup response to heptaldehyde and modulated neuronal transduction protein transcript levels in the olfactory epithelium.
• The number of I7 glomeruli, associated with Olfr2-expressing olfactory sensory neurons (OSN), was altered in an age-dependent manner.
• These neuro-anatomical changes correlated with modified olfactory behaviors and early post-natal odor preferences at weaning.

Conclusions:

• Perinatal exposure to heptaldehyde via maternal feed influences the neuro-anatomical development of the olfactory system in mice pups.
• Early olfactory experiences shape olfactory sensitivity, neural circuitry, and subsequent odor-based behaviors.
• Findings highlight the critical role of the perinatal period in olfactory learning and sensory system programming.