Striatal dopamine D2-like receptor correlation patterns with human obesity and opportunistic eating behavior

Abstract

The obesity epidemic is believed to be driven by a food environment that promotes consumption of inexpensive, convenient, high-calorie, palatable foods. Individual differences in obesity susceptibility or resistance to weight loss may arise because of alterations in the neurocircuitry supporting food reward and eating habits. In particular, dopamine signaling in the ventromedial striatum is thought to encode food reward and motivation, whereas dopamine in the dorsal and lateral striatum orchestrates the development of eating habits. We measured striatal dopamine D2-like receptor binding potential (D2BP) using positron emission tomography with [(18)F]fallypride in 43 human subjects with body mass indices (BMI) ranging from 18 to 45 kg m(-)(2). Opportunistic eating behavior and BMI were both positively associated with D2BP in the dorsal and lateral striatum, whereas BMI was negatively associated with D2BP in the ventromedial striatum. These results suggest that obese people have alterations in dopamine neurocircuitry that may increase their susceptibility to opportunistic overeating while at the same time making food intake less rewarding, less goal directed and more habitual. Whether or not the observed neurocircuitry alterations pre-existed or occurred as a result of obesity development, they may perpetuate obesity given the omnipresence of palatable foods and their associated cues.

Trial registration: ClinicalTrials.gov NCT00846040.

Conflict of interest statement

Conflicts of Interest

The authors have no conflicts of interest.

Figures

Figure 1

A) Striatal correlation pattern of dopamine D2-like receptor binding potential (D2BP) with body mass index (BMI) as represented by t-maps showing positive correlations in dorsal and lateral striatum and negative correlations in ventromedial striatum. B) Striatal associations between D2BP and BMI as represented by β-maps within significant clusters after correcting for multiple comparisons.

Figure 1

A) Striatal correlation pattern of dopamine D2-like receptor binding potential (D2BP) with body mass index (BMI) as represented by t-maps showing positive correlations in dorsal and lateral striatum and negative correlations in ventromedial striatum. B) Striatal associations between D2BP and BMI as represented by β-maps within significant clusters after correcting for multiple comparisons.

Figure 2

A) Striatal correlation pattern of D2BP with opportunistic eating behavior as represented by t-maps showing positive correlations in the lateral striatum and negative correlations in the ventromedial striatum. B) Positive associations between D2BP with opportunistic eating behavior as represented by β-maps within significant clusters in the lateral striatum after correcting for multiple comparisons. C) Positive association between D2BP and opportunistic eating behavior corrected for BMI as represented by β-maps in significant clusters after correcting for multiple comparisons.

Figure 2

A) Striatal correlation pattern of D2BP with opportunistic eating behavior as represented by t-maps showing positive correlations in the lateral striatum and negative correlations in the ventromedial striatum. B) Positive associations between D2BP with opportunistic eating behavior as represented by β-maps within significant clusters in the lateral striatum after correcting for multiple comparisons. C) Positive association between D2BP and opportunistic eating behavior corrected for BMI as represented by β-maps in significant clusters after correcting for multiple comparisons.

Figure 2

A) Striatal correlation pattern of D2BP with opportunistic eating behavior as represented by t-maps showing positive correlations in the lateral striatum and negative correlations in the ventromedial striatum. B) Positive associations between D2BP with opportunistic eating behavior as represented by β-maps within significant clusters in the lateral striatum after correcting for multiple comparisons. C) Positive association between D2BP and opportunistic eating behavior corrected for BMI as represented by β-maps in significant clusters after correcting for multiple comparisons.

Figure 3

Correlations between dopamine D2-like receptor binding potential (D2BP) and BMI within striatal regions of interest. Positive correlations were found in (A) caudate, and (B) putamen, but not in (C) the accumbens area.