Biology subjects

Lecours, C.

Publications and source records attributed to Lecours, C..

2 recordsLinked to original sources

bioRxiv2019

Essential omega-3 fatty acids tune microglial phagocytosis of synaptic elements in the developing brain

Omega-3 fatty acids (n-3 polyunsaturated fatty acids; n-3 PUFAs) are essential for the functional maturation of the brain. Westernization of dietary habits in both developed and developing countries is accompanied by a progressive reduction in dietary intake of n-3 PUFAs. Low maternal intake of n-3 PUFAs has been linked to neurodevelopmental diseases in epidemiological studies, but the mechanisms by which a n-3 PUFA dietary imbalance affects CNS development are poorly understood. Active microglial engulfment of synaptic elements is an important process for normal brain development and altered synapse refinement is a hallmark of several neurodevelopmental disorders. Here, we identify a molecular mechanism for detrimental effects of low maternal n-3 PUFA intake on hippocampal development. Our results show that maternal dietary n-3 PUFA deficiency increases microglial phagocytosis of synaptic elements in the developing hippocampus, through the activation of 12/15- lipoxygenase (LOX)/12-HETE signaling, which alters neuronal morphology and affects cognition in the postnatal offspring. While women of child bearing age are at higher risk of dietary n-3 PUFA deficiency, these findings provide new insights into the mechanisms linking maternal nutrition to neurodevelopmental disorders.\n\nOne Sentence SummaryLow maternal omega-3 fatty acids intake impairs microglia-mediated synaptic refinement via 12-HETE pathway in the developing brain.

neuroscience↗

bioRxiv2018

Cell-lineage specificity of primary cilia during epididymis post-natal development

Primary cilia are sensory organelles that orchestrate major signaling pathways during organ development and homeostasis. By using a double Arl13b/mCherry-Cetn2/GFP transgenic mouse model, we characterized the spatio-temporal localization of primary cilia in the epididymis, from birth to adulthood. We report here a constitutive localisation of primary cilia in peritubular myoid cells and a dynamic profiling in differentiated epithelial cells throughout post-natal development. While primary cilia are present at the apical pole of the undifferentiated epithelial cells from birth to puberty, they are absent from the apical pole of the epithelium in adults, where they appear exclusively associated with cytokeratin 5-positive basal cells. Exogenous labeling of primary cilia marker Arl13b and IFT88 confirmed the cell lineage specific localization of primary cilia in basal cells and myoid cells in human epididymides. From whole epididymis tissues and serum-free cultures of DC2 murine epididymal principal cell lines we determined that primary cilia from the epididymis are associated with the polycystic kidney disease-related proteins polycystin 1 (PC1) and polycystin 2 (PC2), and Gli3 Hedgehog signaling transcription factor. Thus, our findings unveil the existence of primary cilia sensory organelles, which have the potential to mediate mechano/ chemo-signaling events in the epididymis.

developmental biology↗