Relationships between plasma leptin concentrations and human brain structure: A voxel-based morphometric study

Abstract

We have previously demonstrated that obese people have reduced grey matter (GM) in several brain areas, including regions implicated in the regulation of taste (i.e., inferior frontal operculum and postcentral gyrus), reward (i.e., putamen), and behavioral processing (i.e., middle frontal gyrus), compared with their lean counterparts. It is well established that the brain may serve as a direct target for adiposity signals, one of the most important being leptin. We investigated the relationships between fasting plasma leptin concentrations and brain tissue composition in a group of 32 young adult Caucasians (12M/20F, age 32±1 y, body fat 29±1%, mean ± SE) with normal glucose tolerance by using voxel-based morphometry of magnetic resonance imaging scans. Fasting plasma leptin concentrations were positively correlated with grey matter (GM) volumes of the left cerebellum and left inferior temporal gyrus and negatively associated with GM volumes of the left inferior frontal operculum, left postcentral gyrus, and right putamen (P<0.001, uncorrected for multiple comparisons) after adjustment for sex, percent body fat, age, fasting plasma insulin concentrations (i.e., the major determinants of plasma leptin), and global GM volume (thus allowing for an assessment of regional effects only). This study showed an independent, negative correlation between fasting plasma leptin concentrations, which are increased in obesity, and the volumes of GM in brain areas where obese people have reduced GM compared to their lean counterparts. These relationships may explain some of the abnormalities in brain morphology recently found to be associated with excess body fatness.

Brain Activation by Visual Food-Related Stimuli and Correlations with Metabolic and Hormonal Parameters: A fMRI Study

“…Stimulation of the hypothalamus by leptin results in the suppression of food intake, stimulation of satiated behaviour, and energy expenditure [40][41][42][43]. Also, in obese subjects, correlations have recently been reported between leptin and regional grey matter volumes [44].…”

Diabetes and overweight associate with non‐APOE4 genotype in an alzheimer's disease population

“…Leptin receptors also are found in hippocampus and other brain regions affected by AD, and leptin has been shown to facilitate hippocampal synaptic plasticity and cognition [Harvey et al, 2005]. Overweight is associated with increased levels of circulating leptin and leptin resistance [Unger, 2003], and increased leptin levels with obesity are associated with regional gray matter volume reductions in humans [Pannacciulli et al, 2006]. Leptin also may modulate beta amyloid levels [Fewlass et al, 2004].…”

Body mass index and brain structure in healthy children and adolescents

“…Indeed, adipokines (e.g. leptin) are elevated in obese individuals and have been linked to structural brain abnormalities as well as cognitive dysfunction in adults [20][21][22]. Inflammatory processes associated with obesity may also be involved, as evidence shows a significant association between elevated inflammatory markers and structural brain abnormalities [23,24].…”