Fig. 3: Neurons have significantly less LDs than astrocytes and artificially increasing LDs prior to NSPC differentiation leads to more neurons.

a qRT-PCR shows that Plin2 is the most abundant Plin member in neurons and astrocytes derived from SVZ NSPCs (n = 3 samples, mean fold change versus Plin1 ± SEM, one-way ANOVA with Dunnett’s multiple comparisons correction, adj. p-values: neurons Plin2 = 0.0002; astrocytes Plin2 < 0.0001, Plin3 < 0.0001, Plin4 < 0.0001, Plin5 = 0.0003). b NSPC-derived neurons express significantly less Plin2 than NSPCs, while NSPC-derived astrocytes express amounts comparable to NSPCs (n = 3 samples, mean fold change ± SEM, one-way ANOVA with Dunnett’s multiple comparisons correction, prol vs neurons adj. p-value:0.0011). c NSPC-derived astrocytes (GFAP, green, broken arrowheads) contain many LDs (PLIN2, red) whereas NSPC-derived neurons (MAP2AB, white, filled arrowheads), contain less LDs. Representative images are maximum intensity projections. DAPI-positive nuclei (blue). Results were similar among 60 images from 3 coverslips. d 3D reconstruction of neurons and astrocytes revealed significantly increased LD numbers and total LD volume in astrocytes compared to neurons. (n = 50 neurons and n = 52 astrocytes from 3 coverslips, Mann–Whitney test, two-tailed, p < 0.0001). Each dot represents a cell, medians are shown in red. e Schematic illustration depicting the loading and efflux paradigm used. f OA-loading leads to a massive increase in LDs in proliferating SVZ NSPCs while fatty acid-free BSA reduces the LD accumulation. Representative images are maximum intensity projections. PLIN2 (white), DAPI-positive nuclei (blue). g Quantification of PLIN2 area covered with loading and efflux. Bar graphs represent mean ± SEM. (n = 6 coverslips from 2 experiments, Brown-Forsythe ANOVA, Dunnett’s multiple comparisons correction, adj. p-values: Ctrl vs. OA 1:100 = 0.0023; Ctrl vs. OA 1:20 = 0.0088; Ctrl vs. BSA 1:100 = 0.0398; Ctrl vs. BSA 1:20 = 0.0010). h Lipid loading at the NSPC stage influences the number of neurons (MAP2AB, white) formed after differentiation induction. Representative images are maximum intensity projections. DAPI-positive nuclei (blue). i Quantification of MAP2AB positive neurons shows a significant increase in the 0.5 mM OA condition compared to control NSPCs. Bar graphs represent mean ± SEM. (n = 6 coverslips from 2 experiments, one-way ANOVA, Holm-Sidak corrections, adj. p-value = 0.0057). Asterisks indicate the following p-values: ** < 0.01; *** < 0.001.