Fig 1: Clearance of Senescent Cells Partially Reverses the Neural Progenitor Cell Depletion Induced by Obesity(A) Each hemisphere of INK-ATTAC lean and high-fat (HF) mouse brains was either dissociated into a single-cell suspension or processed for IHC/IF. Dissociated brain cells were labeled with metal-conjugated antibodies and processed for cytometry by time of flight (CyTOF).(B and D) Spanning-tree progression analysis of density-normalized events (SPADE) was performed on brain cell populations identified by markers shown on the micrographs. Heatmap shows the intensity of the antibody signal, and the size of each spot is determined by the number of cells within this population.(C) CyTOF shows differences in brain cell populations of INK-ATTAC chow- and HFD-fed mice, which were treated with vehicle or AP20187.(E–G) Frequencies of cells expressing the markers (E) doublecortin (Dcx) (t(13) = 3.057, p = 0.0092; t(15) = 2.236, p = 0.041), (F) CD133 (t(6.291) = 3.339, p = 0.0146; t(9.674) = 3.383, p = 0.0073), and (G) Nestin (t(13) = 4.405, p = 0.0007; t(15) = 2.217, p = 0.0425) were quantified.(H) Representative images of Dcx staining in the olfactory bulb of chow- and HFD-fed mice treated with vehicle or AP20187 (scale bars, 250 µm). White boxes show magnified regions (scale bars, 200 µm).(I and J) (I) Quantitative analysis of the Dcx-positive area of the granular layer in the olfactory lobe of lean and obese INK-ATTAC mice (t(6) = 2.707, p = 0.0352; U = 1, p = 0.0476) and (J) correlation between area occupied by Dcx+ cells in the granular layer of the olfactory bulb and frequencies of Dcx+ cells from the whole brain measured by CyTOF (r = 0.616, p = 0.0111).(K and L) Correlations (linear regression analysis) between frequencies of periventricular glia exhibiting accumulation of lipid droplets and frequencies of cells expressing markers of neurogenesis and ependymal cells (determined by CyTOF): (K) Nestin (r = -0.5887, p = 0.002) and (L) Dcx (r = -0.5022, p = 0.0105).(M and N) Correlations (linear regression analysis) between distance traveled in the central zone and the frequencies of cells expressing (M) Nestin (r = 0.487, p = 0.0074) and (N) Dcx (r = 0.5749, p = 0.0011) (determined by CyTOF).Data are from n = 5–9 mice per group for (C)–(G); n = 2–6 mice per group for (I); n = 11 mice per group for (J); n = 29 mice per group for (K)–(N). Mean ± SEM plotted. *p = 0.05 and **p = 0.001.