A Mechanism for Behavioral Maturation in Male Mice
Jule González Delgado, Katrin Pickrodt, Yuanyuan Ji, Sarah Krüger, Jana F Rieß et al.
(see article e2062242025)
González Delgado et al. explored whether there are long-term neural changes that occur as the brain matures during puberty and adolescence. Using young male mice, they discovered an increase in cortical neuron dendrite morphology and a rearrangement of dendritic spines during emerging adulthood. This change in dendrite complexity was not only cortical layer specific, but it also changed throughout adolescence and was no longer present in adulthood. These distinct, dynamic dendritic changes point to structural measures for long-range cortical rewiring occurring during puberty and adolescence.
Probing a potential mechanism for this, the authors examined whether actin filament formation, which influences cellular morphology, contributed to the observed cortical layer-specific and age-dependent dendrite structural changes. They specifically looked at the role of an actin nucleator called Cobl because actin nucleators trigger actin filament formation. González Delgado and colleagues found that Cobl expression was required for the cortical layer-specific and age-dependent morphological changes. These structural changes supported behavioral maturation—when mice lacked Cobl during adolescence, this led to high-risk behavior. This study sheds light on the molecular mechanisms that support brain maturation in adolescence, at least in males.
This sagittal section of a mouse brain shows the expression of Cobl (green) and a marker for neurons (blue). See González Delgado et al. for more information.
Exploring Gray Matter Changes in Childhood and Adolescence
Yana Fandakova, Naftali Raz, Ulman Lindenberger, Dalal Khatib, Usha Rajan, and Jeffrey Stanley
(see article e2222242025)
During childhood and adolescence, the brain's gray matter changes drastically. This may be due to changes in its main component, neuropil, but studies have not uncovered the neurobiological mechanisms of gray matter changes at early life stages. In a longitudinal study of children aged 6–14, Fandakova and colleagues examined changes in metabolites associated with brain energetics as well as the development and degradation of membrane phospholipids. Using phosphorous magnetic resonance spectroscopy, the authors discovered that metabolites linked to neuropil contraction and expansion changed developmentally. These changes were associated with structural changes in the prefrontal cortex. According to the authors, this work features a new approach to unveil the key neurobiological mechanisms of prefrontal cortex gray matter changes through childhood and adolescence. The approach used in this study could potentially be useful in pediatric populations with neurodevelopmental or psychiatric conditions.
Footnotes
This Week in The Journal was written by Paige McKeon
