F-18-FEAnGA for PET of beta-Glucuronidase Activity in NeuroinflammationFarinha Antunes, I., Doorduin, J., Haisma, H. J., Elsinga, P. H., van Waarde, A., Willemsen, A. T. M., Dierckx, R. A. & de Vries, E. F. J., 1-Mar-2012, In : Journal of Nuclear Medicine. 53, 3, p. 451-458 8 p.
Research output: Contribution to journal › Article › Academic › peer-review
Activation of microglia is a hallmark of inflammatory, infectious, and degenerative diseases of the central nervous system. Several studies have indicated that there is an increase in release of beta-glucuronidase by activated microglia into the extracellular space at the site of neuroinflammation. beta-glucuronidase is involved in the hydrolysis of glycosaminoglycans on the cell surface and the degradation of the extracellular matrix. Therefore, beta-glucuronidase might be a biomarker for ongoing neurodegeneration induced by neuroinflammation. In this study, we investigated whether the PET tracer F-18-FEAnGA was able to detect beta-glucuronidase release during neuroinflammation in a rat model of herpes encephalitis. Methods: Male Wistar rats were intranasally inoculated with herpes simplex virus 1 (HSV-1) or phosphate-buffered saline as a control. C-11-(R)-PK11195 and F-18-FEAnGA small-animal PET scans were acquired for 60 min. Logan graphical analysis was used to calculate F-18-FEAnGA distribution volumes (DVLogan) in various brain areas. Results: After administration of F-18-FEAnGA, the area under the activity concentration-versus-time curve of the whole brain was 2 times higher in HSV-1-infected rats than in control rats. In addition, the DVLogan of F-18-FEAnGA was most increased in the frontopolar cortex, frontal cortex, bulbus olfactorius, cerebral cortex, cerebellum, and brainstem of HSV-1-infected rats, when compared with control rats. The conversion of F-18-FEAnGA to 4-hydroxy-3-nitrobenzyl alcohol was found to be 1.6 times higher in HSV-1-infected rats than in control rats and correlated with the DVLogan of F-18-FEAnGA in the same areas of the brain. Furthermore, the DVLogan of F-18-FEAnGA also correlated with beta-glucuronidase activity in the same brain regions. In addition, DVLogan of F-18-FEAnGA showed a tendency to correlate with C-11-(R)-PK11195 uptake (marker for activated microglia) in the same brain regions. Conclusion: Despite relatively low brain uptake, F-18-FEAnGA was able to detect an increased release of beta-glucuronidase during neuroinflammation.
|Number of pages||8|
|Journal||Journal of Nuclear Medicine|
|Publication status||Published - 1-Mar-2012|
- HSV-1, beta-glucuronidase, [F-18]FEAnGA, PET, neuroinflammation, ALZHEIMERS-DISEASE, ENZYME-ACTIVITIES, BRAIN, ENCEPHALITIS, INFLAMMATION, DISORDERS, MICROGLIA, BINDING, RELEASE