The effect of aquaporin‐4 inhibition on cerebrospinal fluid‐tissue water exchange in mouse brain detected by magnetization transfer indirect spin labeling MRI

• Published in: NMR in biomedicine 2024-07, Vol.37 (7), p.e5093-n/a
• Main Authors: Chen, Zilin, Lai, Joseph H. C., Xu, Jiadi, Zhang, Hao, Huang, Jianpan, Chan, Kannie W. Y.
• Format: Article
• Language: English
• Subjects: Animals; AQP4; Aquaporin 4; Aquaporin 4 - antagonists & inhibitors; Aquaporin 4 - metabolism; Aquaporins; Body Water - metabolism; Brain; Brain - diagnostic imaging; Brain - metabolism; Cerebrospinal fluid; Cerebrospinal Fluid - diagnostic imaging; Cerebrospinal Fluid - metabolism; CSF; Exchanging; Labeling; Magnetic Resonance Imaging; Magnetization; magnetization transfer; magnetization transfer indirect spin labeling; Male; Mice; Mice, Inbred C57BL; MRI; Neuroimaging; Niacinamide - analogs & derivatives; Spin labeling; Spin Labels; Thiadiazoles; Tissues; Water - metabolism; Water exchange
• ISSN: 0952-3480; 1099-1492; 1099-1492
• DOI: 10.1002/nbm.5093

The fluid transport of cerebrospinal fluid (CSF) and interstitial fluid in surrounding tissues plays an important role in the drainage pathway that facilitates waste clearance from the brain. This pathway is known as the glymphatic or perivascular system, and its functions are dependent on aquaporin‐4 (AQP4). Recently, magnetization transfer indirect spin labeling (MISL) magnetic resonance imaging (MRI) has been proposed as a noninvasive and noncontrast‐enhanced method for detecting water exchange between CSF and brain tissue. In this study, we first optimized the MISL sequence at preclinical 3 T MRI, and then studied the correlation of MISL in CSF with magnetization transfer (MT) in brain tissue, as well as the altered water exchange under AQP4 inhibition, using C57BL/6 mice. Results showed a strong correlation of MISL signal with MT signal. With the AQP4 inhibitor, we observed a significant decrease in MISL value (P