High-Salt Exposure During Perinatal Development Enhances Stress Sensitivity

Area of Science:

• Neuroscience
• Developmental Biology
• Nutritional Science

Background:

• Excessive dietary sodium during pregnancy can negatively affect offspring cardiovascular health and adult salt preference.
• The long-term effects of maternal high salt intake on offspring brain development and behavior remain largely unexplored.

Purpose of the Study:

• To investigate the impact of maternal perinatal salt exposure on offspring brain morphology and behavior.
• To examine structural plasticity in the prefrontal cortex (PFC) and nucleus accumbens (NAc) in weanling and adult offspring.
• To assess reward- and stress-driven behaviors in adult offspring following maternal high salt intake.

Main Methods:

• Utilized cellular and behavioral approaches in a rat model.
• Analyzed spine density in specific PFC subregions (infralimbic and prelimbic) and the NAc shell.
• Assessed reward behaviors (sucrose preference, cocaine CPP) and stress responses (forced swim test, plasma corticosterone levels).

Main Results:

• Maternal high salt intake led to altered spine densities in the PFC and NAc of weanling rats, with some changes persisting into adulthood.
• Offspring of high-salt fed dams showed increased stress sensitivity, indicated by reduced swimming time and heightened plasma CORT levels during stress.
• No significant effects of maternal salt intake were observed on reward-driven behaviors.

Conclusions:

• Perinatal salt exposure induces lasting structural changes in key brain regions of offspring.
• Early life high salt intake can increase offspring's sensitivity to stress.
• These findings highlight the critical role of maternal diet during pregnancy on offspring neurodevelopment and stress regulation.