Inflammatory markers and bone mass in children with overweight/obesity: the role of muscular fitness

Objectives To examine which inflammatory markers are associated with bone mass and whether this association varies according to muscular fitness in children with overweight/obesity. Methods Plasma interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), epidermal growth factor, vascular endothelial growth factor A (VEGF), and C-reactive protein were analyzed in 55 children aged 8–11 years. A muscular fitness score was computed. Bone mineral content (BMC) of the total body-less head (TBLH) and lumbar spine (LS) were assessed using dual-energy x-ray absorptiometry. Results IL-6 (β = −0.136) and VEGF (β = −0.099) were associated with TBLH BMC, while TNF-α (β = −0.345) and IL-1β (β = 0.212) were associated with LS BMC (P < 0.05). The interaction effect of muscular fitness showed a trend in the association of VEGF with TBLH BMC (P = 0.122) and TNF-α with LS BMC (P = 0.057). Stratified analyses by muscular fitness levels showed an inverse association of VEGF with TBLH BMC (β = −0.152) and TNF-α with LS BMC (β = −0.491) in the low-fitness group, while no association was found in the high-fitness group. Conclusion IL-6, VEGF, TNF-α, and IL-1β are significantly associated with bone mass. Higher muscular fitness may attenuate the adverse effect of high VEGF and TNF-α on bone mass

Neurotrophic factors and brain health in children with overweight and obesity: the role of cardiorespiratory fitness

Neurotrophic factors and cardiorespiratory fitness are both considered important in developmental trajectories but their link to brain health remains poorly understood. The aims of the study were to examine whether levels of plasma-derived neurotrophic factors were associated with brain health indicators in children with overweight or obesity; and to test whether these associations were moderated by cardiorespiratory fitness. 100 children (41% girls) were included in this analysis. Plasma levels of brain-derived neurotrophic factor, insulin-like growth factor-1, vascular endothelial growth factor A, and epidermal growth factor were determined by XMap technology. Academic performance and executive function were assessed using validated neuropsychological tests. Hippocampal volume was measured using magnetic resonance imaging. Cardiorespiratory fitness was assessed using the 20-m Shuttle Run Test. Insulin-like growth factor-1 was positively associated with cognitive flexibility. Stratified analyses by fitness categories (i.e. unfit vs. fit) showed that brain-derived neurotrophic factor was positively associated with right posterior hippocampal volume in fit children, and epidermal growth factor was negatively associated with right hippocampal, and right anterior hippocampal volumes in their unfit peers, with a moderating role of cardiorespiratory fitness in these associations. However, all these significant associations disappeared after correction for multiple comparisons. The association between neurotrophic factors and brain health indicators in children with overweight/obesity was neither strong nor consistent. These results could help enhance our understanding of determinants of brain health in children with overweight/obesity