Thyrotropin receptor signaling deficiency impairs spatial learning and memory in mice

Area of Science:

• Neuroscience
• Endocrinology
• Molecular Biology

Background:

• Subclinical hyperthyroidism, marked by low thyroid-stimulating hormone (TSH), is linked to cognitive impairment.
• TSH mediates its effects through the TSH receptor (TSHR), but its role in cognition is unclear.

Purpose of the Study:

• To investigate the role of TSHR signaling in cognitive function.
• To determine if TSHR deficiency impacts learning and memory.

Main Methods:

• Utilized Tshr knockout mice (Tshr-/-) to study the effects of TSHR deletion.
• Assessed performance in learning and memory tests.
• Examined hippocampal structure, including dendritic spine and synaptic density.
• Analyzed synapse-related gene expression in the hippocampus.

Main Results:

• Tshr-/- mice showed significantly impaired performance in learning and memory tests.
• Reduced dendritic spine density and excitatory synaptic density were observed in the hippocampus of Tshr-/- mice.
• Alterations in synapse-related gene expression were noted in the hippocampus of Tshr-/- mice.

Conclusions:

• TSHR signaling deficiency impairs spatial learning and memory.
• This study reveals a novel role for TSHR signaling in regulating brain function, particularly in the hippocampus.