Stability in Brain Glucose Metabolism Following Brown Adipose Tissue Inactivation in Chinese Adults

Q Miao,S Zhang,M.F Zeng,Z.Y Zhang,Y.M Li,X.L Zhao,Y.H Guan,Q.Y Zhang,H.Y Ye,C.T Zuo

doi:10.3174/ajnr.a3006

Q Miao, S Zhang + Show 8 more

Open Access

https://doi.org/10.3174/ajnr.a3006

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Abstract

The thermogenesis of BAT is believed to be controlled through some pathways initiated in the brain, though the changes in brain activity among different states of BAT-positive subjects are still unclear. We hypothesized that some significant differences of regional cerebral metabolism between various groups were related to the BAT activities regardless of temperature changes. Relative regional cerebral glucose metabolism was compared between 15 healthy subjects with activated BAT and 30 healthy controls without activated BAT by using a brain FDG-PET scan. A follow-up PET scan was performed to assess metabolic changes of the brain when BAT activity was eliminated by heat exposure. Compared with controls, BAT-positive subjects exhibited lower activity in the inferior parietal lobule, limbic system, and frontal lobe and higher activity in the precuneus before heat exposure. Compared with the BAT elimination status, subjects with activated BAT showed a decreased metabolism in the parietal lobe, frontal lobe, culmen, cingulate gyrus, and sublobar region. Compared with controls, BAT-positive subjects after BAT inactivation had significant hypometabolic areas in the temporal lobe and limbic lobe and hypermetabolic areas in the parietal lobe. Our findings illustrate that changes of regional cerebral metabolism are related to BAT activities regardless of temperature changes. This before-after controlled study supports the finding that the brain responses appear to be active in modulating the metabolic function of BAT activity.

Highlights

AND PURPOSE: The thermogenesis of BAT is believed to be controlled through some pathways initiated in the brain, though the changes in brain activity among different states of BAT-positive subjects are still unclear
Our findings illustrate that changes of regional cerebral metabolism are related to BAT activities regardless of temperature changes
In 2007, Nedergaard et al3 reviewed several studies showing that BAT is present in adult humans; adult BAT activity is acutely cold-induced

Summary

Methods

Relative regional cerebral glucose metabolism was compared between 15 healthy subjects with activated BAT and 30 healthy controls without activated BAT by using a brain FDG-PET scan. Subjects and Procedures Between December 2009 and May 2010, a group of 15 healthy subjects with activated BAT (10 women, 5 men; mean age, 35.67 Ϯ 6.66 years; range, 25– 46 years) were collected at the Huashan PET/CT center, Fudan University. Scans and reports for 30 sex-, age-, BMI-, outdoor temperature–, and FPGmatched healthy controls without activated BAT (20 women, 10 men; mean age, 37.43 Ϯ 6.14 years; range, 26 – 47 years) (On-line Table 1) were collected. None of these subjects had received ␤-blockers to prevent activating BAT before the PET/CT scan. Screening procedures included complete medical examinations, routine laboratory evaluations, and MR imaging (Trio 3T; Siemens, Shanghai, China) to exclude potential participants with significant body and brain diseases, and a neuropsychiatric evaluation

Results

Discussion

Conclusion