Fluoride exposure during development affects both cognition and emotion in mice

Area of Science:

• Neuroscience
• Toxicology
• Developmental Biology

Background:

• Previous research indicates potential neurodevelopmental risks associated with sodium fluoride (NaF) exposure.
• Understanding the specific impacts of developmental NaF exposure on the brain is crucial for public health.

Purpose of the Study:

• To evaluate the developmental neurotoxicity of NaF by assessing cognitive function and emotional behavior in mice.
• To determine the dose-dependent effects of NaF on neurodevelopmental outcomes.

Main Methods:

• Balb/C mice were exposed to varying concentrations of NaF (2, 5, 10 mg/L) in drinking water from weaning (4 weeks) for 4 weeks.
• Cognitive function was assessed using the novel object recognition test and Morris water maze.
• Emotional behavior was evaluated through the elevated-plus maze and tail suspension test.

Main Results:

• Significant alterations in exploration preference (novel object recognition) were observed at 5 and 10 mg/L NaF.
• Mice exposed to 5 and 10 mg/L NaF exhibited impaired spatial learning and memory in the Morris water maze.
• Elevated anxiety-like behavior (reduced open arm time in elevated-plus maze) and depression-like behavior (increased immobility in tail suspension test) were noted at higher NaF concentrations.

Conclusions:

• Developmental exposure to NaF can induce significant cognitive deficits in mice.
• NaF exposure during development is associated with anxiety- and depression-like behaviors.
• These findings highlight the potential neurotoxic effects of NaF during critical developmental periods.