PT - JOURNAL ARTICLE AU - Brendel, Matthias AU - Focke, Carola AU - Blume, Tanja AU - Peters, Finn AU - Deussing, Maximilian AU - Probst, Federico AU - Jaworska, Anna AU - Overhoff, Felix AU - Albert, Nathalie AU - Lindner, Simon AU - von Ungern-Sternberg, Barbara AU - Bartenstein, Peter AU - Haass, Christian AU - Kleinberger, Gernot AU - Herms, Jochen AU - Rominger, Axel TI - Time Courses of Cortical Glucose Metabolism and Microglial Activity Across the Life Span of Wild-Type Mice: A PET Study AID - 10.2967/jnumed.117.195107 DP - 2017 Dec 01 TA - Journal of Nuclear Medicine PG - 1984--1990 VI - 58 IP - 12 4099 - http://jnm.snmjournals.org/content/58/12/1984.short 4100 - http://jnm.snmjournals.org/content/58/12/1984.full SO - J Nucl Med2017 Dec 01; 58 AB - Contrary to findings in the human brain, 18F-FDG PET shows cerebral hypermetabolism of aged wild-type (WT) mice relative to younger animals, supposedly due to microglial activation. Therefore, we used dual-tracer small-animal PET to examine directly the link between neuroinflammation and hypermetabolism in aged mice. Methods: WT mice (5–20 mo) were investigated in a cross-sectional design using 18F-FDG (n = 43) and translocator protein (TSPO) (18F-GE180; n = 58) small-animal PET, with volume-of-interest and voxelwise analyses. Biochemical analysis of plasma cytokine levels and immunohistochemical confirmation of microglial activity were also performed. Results: Age-dependent cortical hypermetabolism in WT mice relative to young animals aged 5 mo peaked at 14.5 mo (+16%, P < 0.001) and declined to baseline at 20 mo. Similarly, cortical TSPO binding increased to a maximum at 14.5 mo (+15%, P < 0.001) and remained high to 20 mo, resulting in an overall correlation between 18F-FDG uptake and TSPO binding (R = 0.69, P < 0.005). Biochemical and immunohistochemical analyses confirmed the TSPO small-animal PET findings. Conclusion: Age-dependent neuroinflammation is associated with the controversial observation of cerebral hypermetabolism in aging WT mice.