Aquaporin-4 expression in the human choroid plexus.
Felix Deffner1, Corinna Gleiser1, Ulrich Mattheus1
1Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Österbergstr. 3, 72074, Tübingen, Germany.
Cellular and Molecular Life Sciences : CMLS
|January 24, 2022
Summary
Aquaporin-4 (AQP4) is newly found in the aging choroid plexus (CP), potentially altering cerebrospinal fluid (CSF) production and flow in older individuals.
Area of Science:
- Neuroscience
- Cell Biology
- Physiology
Background:
- The choroid plexus (CP) produces cerebrospinal fluid (CSF) and forms the blood-CSF barrier.
- CP epithelial cells express aquaporin-1 (AQP1) apically.
- Aquaporin-4 (AQP4) is typically found in astrocytes and ventricle-lining ependymal cells.
Purpose of the Study:
- To investigate the expression of aquaporins in the human choroid plexus.
- To determine if AQP4 expression in the CP is age-related.
Main Methods:
- Immunofluorescence and quantitative PCR (qPCR) on human CP tissue.
- Electron microscopy to identify orthogonal arrays of particles.
- Analysis of aquaporin expression in mouse brains across different age groups.
Main Results:
- AQP1 and unexpectedly, AQP4, were expressed in the CP epithelium of elderly human donors.
- AQP4 mRNA levels significantly increased in the CP of old mice compared to young and adult mice.
- A trend for inverse correlation between AQP4 and Na/K-ATPase expression was observed.
Conclusions:
- AQP4 is expressed in the aging human CP, suggesting a role in age-related changes in CSF production.
- This AQP4 expression may represent a compensatory or detrimental mechanism affecting CSF dynamics.
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