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A 24-hour temporal profile of in vivo brain and heart pet imaging reveals a nocturnal peak in brain 18F-fluorodeoxyglucose uptake.

van der Veen DR, Shao J, Chapman S, Leevy WM, Duffield GE - PLoS ONE (2012)

Bottom Line: Reports applying the 2-deoxy-D[(14)C]-glucose method for the quantitative determination of the rates of local cerebral glucose utilization indicate only a small number of brain regions exhibiting a day versus night variation in glucose utilization.In contrast, our data show 24-hour patterns in glucose uptake in most of the brain regions examined, including several regions that do not show a difference in glucose utilization.Our data also emphasizes a methodological requirement of controlling for the time of day of scanning FDG uptake in the brain in both clinical and pre-clinical settings, and suggests waveform normalization of FDG measurements at different times of the day.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana, United States of America.

ABSTRACT
Using positron emission tomography, we measured in vivo uptake of (18)F-fluorodeoxyglucose (FDG) in the brain and heart of C57Bl/6 mice at intervals across a 24-hour light-dark cycle. Our data describe a significant, high amplitude rhythm in FDG uptake throughout the whole brain, peaking at the mid-dark phase of the light-dark cycle, which is the active phase for nocturnal mice. Under these conditions, heart FDG uptake did not vary with time of day, but did show biological variation throughout the 24-hour period for measurements within the same mice. FDG uptake was scanned at different times of day within an individual mouse, and also compared to different times of day between individuals, showing both biological and technical reproducibility of the 24-hour pattern in FDG uptake. Regional analysis of brain FDG uptake revealed especially high amplitude rhythms in the olfactory bulb and cortex, while low amplitude rhythms were observed in the amygdala, brain stem and hypothalamus. Low amplitude 24-hour rhythms in regional FDG uptake may be due to multiple rhythms with different phases in a single brain structure, quenching some of the amplitude. Our data show that the whole brain exhibits significant, high amplitude daily variation in glucose uptake in living mice. Reports applying the 2-deoxy-D[(14)C]-glucose method for the quantitative determination of the rates of local cerebral glucose utilization indicate only a small number of brain regions exhibiting a day versus night variation in glucose utilization. In contrast, our data show 24-hour patterns in glucose uptake in most of the brain regions examined, including several regions that do not show a difference in glucose utilization. Our data also emphasizes a methodological requirement of controlling for the time of day of scanning FDG uptake in the brain in both clinical and pre-clinical settings, and suggests waveform normalization of FDG measurements at different times of the day.

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Time-of-day specific analysis of FDG uptake in heart.(A) Whole heart FDG uptake in the same C57Bl/6 mice as Figure 2 (N = 37) plotted at the time of measurement. There is no statistically significant variation of total FDG uptake for grouped averages (B). The within individual comparison (C) also shows no uniform FDG uptake at different times of the day.
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pone-0031792-g003: Time-of-day specific analysis of FDG uptake in heart.(A) Whole heart FDG uptake in the same C57Bl/6 mice as Figure 2 (N = 37) plotted at the time of measurement. There is no statistically significant variation of total FDG uptake for grouped averages (B). The within individual comparison (C) also shows no uniform FDG uptake at different times of the day.

Mentions: In contrast to whole brain FDG uptake, heart FDG uptake shows no time-of-day difference (Figure 3a; proc mixed, P>0.05). Variability of heart FDG uptake was much larger than whole brain FDG uptake (compare Figure 2a to Figure 3a), and mean heart FDG uptake was similar for each of the four time points (Proc mixed, least square means contrast: P's>0.05; Figure 3b). Within individual comparison of heart FDG uptake confirmed no time-of-day variation between measurements centered on ZT 18 vs. ZT 24/0 and ZT 6 vs. ZT 12 (paired t-test, P's>0.05; Figure 3c).


A 24-hour temporal profile of in vivo brain and heart pet imaging reveals a nocturnal peak in brain 18F-fluorodeoxyglucose uptake.

van der Veen DR, Shao J, Chapman S, Leevy WM, Duffield GE - PLoS ONE (2012)

Time-of-day specific analysis of FDG uptake in heart.(A) Whole heart FDG uptake in the same C57Bl/6 mice as Figure 2 (N = 37) plotted at the time of measurement. There is no statistically significant variation of total FDG uptake for grouped averages (B). The within individual comparison (C) also shows no uniform FDG uptake at different times of the day.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3285174&req=5

pone-0031792-g003: Time-of-day specific analysis of FDG uptake in heart.(A) Whole heart FDG uptake in the same C57Bl/6 mice as Figure 2 (N = 37) plotted at the time of measurement. There is no statistically significant variation of total FDG uptake for grouped averages (B). The within individual comparison (C) also shows no uniform FDG uptake at different times of the day.
Mentions: In contrast to whole brain FDG uptake, heart FDG uptake shows no time-of-day difference (Figure 3a; proc mixed, P>0.05). Variability of heart FDG uptake was much larger than whole brain FDG uptake (compare Figure 2a to Figure 3a), and mean heart FDG uptake was similar for each of the four time points (Proc mixed, least square means contrast: P's>0.05; Figure 3b). Within individual comparison of heart FDG uptake confirmed no time-of-day variation between measurements centered on ZT 18 vs. ZT 24/0 and ZT 6 vs. ZT 12 (paired t-test, P's>0.05; Figure 3c).

Bottom Line: Reports applying the 2-deoxy-D[(14)C]-glucose method for the quantitative determination of the rates of local cerebral glucose utilization indicate only a small number of brain regions exhibiting a day versus night variation in glucose utilization.In contrast, our data show 24-hour patterns in glucose uptake in most of the brain regions examined, including several regions that do not show a difference in glucose utilization.Our data also emphasizes a methodological requirement of controlling for the time of day of scanning FDG uptake in the brain in both clinical and pre-clinical settings, and suggests waveform normalization of FDG measurements at different times of the day.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana, United States of America.

ABSTRACT
Using positron emission tomography, we measured in vivo uptake of (18)F-fluorodeoxyglucose (FDG) in the brain and heart of C57Bl/6 mice at intervals across a 24-hour light-dark cycle. Our data describe a significant, high amplitude rhythm in FDG uptake throughout the whole brain, peaking at the mid-dark phase of the light-dark cycle, which is the active phase for nocturnal mice. Under these conditions, heart FDG uptake did not vary with time of day, but did show biological variation throughout the 24-hour period for measurements within the same mice. FDG uptake was scanned at different times of day within an individual mouse, and also compared to different times of day between individuals, showing both biological and technical reproducibility of the 24-hour pattern in FDG uptake. Regional analysis of brain FDG uptake revealed especially high amplitude rhythms in the olfactory bulb and cortex, while low amplitude rhythms were observed in the amygdala, brain stem and hypothalamus. Low amplitude 24-hour rhythms in regional FDG uptake may be due to multiple rhythms with different phases in a single brain structure, quenching some of the amplitude. Our data show that the whole brain exhibits significant, high amplitude daily variation in glucose uptake in living mice. Reports applying the 2-deoxy-D[(14)C]-glucose method for the quantitative determination of the rates of local cerebral glucose utilization indicate only a small number of brain regions exhibiting a day versus night variation in glucose utilization. In contrast, our data show 24-hour patterns in glucose uptake in most of the brain regions examined, including several regions that do not show a difference in glucose utilization. Our data also emphasizes a methodological requirement of controlling for the time of day of scanning FDG uptake in the brain in both clinical and pre-clinical settings, and suggests waveform normalization of FDG measurements at different times of the day.

Show MeSH
Related in: MedlinePlus