Issue Cover (May 2020)

Front cover: Inhibition of insulin‐regulated aminopeptidase (IRAP) activity improves spatial working and recognition memory in rodents. However, the mechanism of its cognitive‐enhancing effect remains unknown. There is a close correlation between dendritic spine density and learning in vivo. Dendritic spines are small protrusions from the dendrites of neurons that serve as contacts with neighboring axons and contain all of the molecular machinery required for synaptic plasticity and long term potentiation, i.e. the storage of memories. Image content: Primary rat hippocampal cultures were exposed to varying concentrations of the IRAP inhibitor HFI‐419 on 14, 17 and 20 div, a period of time when peak dendritic spine formation occurs. At 21 div, hippocampal cells were fixed and immunostained against β‐III tubulin (1:500, green) and drebrin (1:500, red) to visualize neuronal processes and dendritic spines, respectively. Nuclei were counterstained with DAPI (blue). Cultures treated with HFI‐419 had an increased number of total spines when compared with vehicle‐treated cells, suggesting that IRAP inhibition may exert its memory enhancing effects by increasing dendritic spine density. Scale bar = 10 μm.Read the full article   ‘Insulin‐regulated aminopeptidase inhibitor‐mediated increases in dendritic spine density are facilitated by glucose uptake’ by B. Seyer, S. Diwakarla, P. Burns, A. Hallberg, A. Grӧnbladh, M. Hallberg, S.Y. Chai, ( J. Neurochem. 2020, vol. 153 (4), pp. 485–494) on doi: 10.1111/jnc.14880