In vivo imaging of dendritic pruning in dentate granule cells

Data files of the dendritic arbors of all neurons imaged for the following publication:<div><br></div><div>Gonçalves J.T., Bloyd C.W., Shtrahman M, Johnston S.T., Schafer S.T., Parylak S.L., Thanh T., Chang T., Gage F.H., In vivo imaging of dendritic pruning in dentate granule cells, Nature Neurosci.,<i> </i><i>in press, doi:10.1038/nn.4301 </i>(2016)</div><div><br></div><div><div><b>Abstract:</b></div><div>We longitudinally imaged the developing dendrites of adult-born mouse dentate granule cells (DGCs) in vivo and found that they underwent over-branching and pruning. Exposure to an enriched environment and constraint of dendritic growth by disrupting Wnt signaling led to increased branch addition and accelerated growth, which were, however, counteracted by earlier and more extensive pruning. Our results indicate that pruning is regulated in a homeostatic fashion to oppose excessive branching and promote a similar dendrite structure in DGCs.</div></div><div><br></div><div><div><div><div><div><div><div></div></div></div></div><div></div></div><div></div></div><div><div><div></div></div></div></div

Faster Protocol for Endogenous Fatty Acid Esters of Hydroxy Fatty Acid (FAHFA) Measurements

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a recently discovered class of endogenous lipids with antidiabetic and anti-inflammatory activities. Interest in these lipids is due to their unique biological activites and the observation that insulin-resistant people have lower palmitic acid esters of hydroxystearic acid (PAHSA) levels, suggesting that a FAHFA deficiency may contribute to metabolic disease. Rigorous testing of this hypothesis will require the measurement of many clinical samples; however, current analytical workflows are too slow to enable samples to be analyzed quickly. Here we describe the development of a significantly faster workflow to measure FAHFAs that optimizes the fractionation and chromatography of these lipids. We can measure FAHFAs in 30 min with this new protocol versus 90 min using the older protocol with comparable performance in regioisomer detection and quantitation. We also discovered through this optimization that oleic acid esters of hydroxystearic acids (OAHSAs), another family of FAHFAs, have a much lower background signal than PAHSAs, which makes them easier to measure. Our faster workflow was able to quantify changes in PAHSAs and OAHSAs in mouse tissues and human plasma, highlighting the potential of this protocol for basic and clinical applications