👤 Marta Rosário

The effects of different exercise intensities on cognitive outcomes and brain-derived neurotrophic factor (BDNF) concentrations in adolescents with overweight/obesity are not yet fully elucidated. This study aimed: (a) to compare the prevalence of responders to cognitive function and BDNF concentration in adolescents with overweight/obesity participating in a 12-week intervention with high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT), and (b) to analyze whether cardiorespiratory fitness (CRF) can explain differences in inter-individual variability between responders and non-responders. Adolescents with overweight/obesity were assigned to HIIT (n = 15), MICT (n = 14), or CG (n = 24). Anthropometrics, body composition, CRF, basal BDNF, and cognitive performance (Trial Making Test (TMT) and Stroop Test (ST)) were evaluated pre- and post-intervention. Training was performed on stationary bikes (3×/week for 12 weeks). The prevalence of responders in ST and TMT was higher in the HIIT group than in CG (93-62%, p = 0.029; 67-33%, p = 0.043), with no differences in MICT. No group differences were found for BDNF responders (HIIT:73%-MICT:71%-CG:46%, p = 0.263). ST and TMT responders had greater CRF improvements than non-responders. HIIT elicited a higher prevalence of cognitive responders than CG. CRF improvements may partially explain individual variability in responsiveness to cognitive outcomes. This is the first study to examine and compare inter-individual variability in cognitive function and BDNF levels following MICT and HIIT interventions in adolescents with overweight/obesity; Exercise intensity and improvements in cardiorespiratory fitness are key factors for optimizing the cognitive effects of interventions in youth with overweight; Twelve weeks of supervised HIIT and MICT training led to increased rates of cognitive responders among adolescents with overweight/obesity. Show less

The establishment of axon-dendrite polarity is fundamental for radial migration of neurons during cortex development of mammals. We demonstrate that the E3 ubiquitin ligases WW-Containing Proteins 1 and 2 (Wwp1 and Wwp2) are indispensable for proper polarization of developing neurons. We show that knockout of Wwp1 and Wwp2 results in defects in axon-dendrite polarity in pyramidal neurons, and their aberrant laminar cortical distribution. Knockout of miR-140, encoded in Wwp2 intron, engenders phenotypic changes analogous to those upon Wwp1 and Wwp2 deletion. Intriguingly, transcription of the Wwp1 and Wwp2/miR-140 loci in neurons is induced by the transcription factor Sox9. Finally, we provide evidence that miR-140 supervises the establishment of axon-dendrite polarity through repression of Fyn kinase mRNA. Our data delineate a novel regulatory pathway that involves Sox9-[Wwp1/Wwp2/miR-140]-Fyn required for axon specification, acquisition of pyramidal morphology, and proper laminar distribution of cortical neurons. Show less