Maternal Brain TNF-α Programs Innate Fear in the Offspring

Area of Science:

• Neuroscience
• Immunology
• Behavioral Genetics

Background:

• Tumor Necrosis Factor-alpha (TNF-α) is a cytokine involved in immune responses and neuronal function.
• While glia-derived TNF-α regulates synaptic scaling, TNF-α-null mice show no cognitive deficits.
• Innate fear is crucial for survival, balancing exploration and predator avoidance.

Purpose of the Study:

• To investigate the role of maternal TNF-α in offspring innate fear.
• To determine if TNF-α deficit in mothers impacts offspring behavior.
• To identify the critical period and maternal compartment for this effect.

Main Methods:

• Utilized TNF-α-null mice models.
• Conducted cross-fostering experiments.
• Employed conditional knockout strategies to target maternal brain TNF-α during gestation.

Main Results:

• Mothers with a TNF-α deficit programmed offspring to exhibit significantly lower innate fear.
• The effect was traced to a TNF-α deficit specifically within the maternal brain during gestation.
• Hematopoietic TNF-α levels did not account for the observed phenotype.

Conclusions:

• Maternal brain TNF-α acts as a crucial mediator of intergenerational programming of offspring innate fear.
• Maternal TNF-α levels may signal anticipated environmental conditions to the fetus, promoting adaptive behaviors.
• This finding highlights a novel mechanism for environmental influence on offspring behavior via maternal cytokines.