Widespread Cortical Thickness Is Associated With Neuroactive Steroid Levels

Area of Science:

• Neuroscience
• Endocrinology
• Radiology

Background:

• Neuroactive steroids possess regenerative and neuroprotective properties.
• Age-related decline in cortical thickness and neuroactive steroid levels is observed.
• Existing research lacks systematic examination of neuroactive steroid levels and in vivo cortical thickness in humans.

Purpose of the Study:

• To investigate the relationship between serum neuroactive steroid levels and in vivo cortical thickness.
• To identify specific brain regions where this association is present.

Main Methods:

• Assayed serum levels of seven neuroactive steroids in 143 US military veterans.
• Utilized high-resolution structural MRI for cortical surface parcellation into 148 regions.
• Employed regression modeling and False Discovery Rate (FDR) correction to analyze associations.

Main Results:

• Positive correlations were found between allopregnanolone and pregnenolone levels and gray matter thickness.
• These associations were observed in multiple regions of the cingulate, parietal, and occipital association cortices.
• Statistical significance was confirmed with FDR correction (r = 0.20-0.47; p < 0.05).

Conclusions:

• Serum neuroactive steroid levels are positively associated with gray matter cortical thickness in several brain areas.
• These findings suggest potential biomarkers for monitoring therapeutic interventions.
• Further confirmation is needed to establish clinical utility in neuroregenerative therapy studies.