Fig 2: Nasally administered mitochondria enter the brain. (A) Representation of mouse brain sagittal section with ROIs depicting where mitochondria were detected; scale bar 2500 µm. Nasally administered DsRed+/anti-human mitochondria+ mitochondria (yellow) were detected in (B) Ventricle; scale bar 100 µm (C) RMS - DsRed+ (green)/anti-human mitochondria+ (red) mitochondria (yellow) internalized by GFAP+ cells (magenta) in the RMS; scale bars 25 and 10 µm (D) Choroid Plexus (E) Hippocampus (F) Olfactory bulb; scale bars 25 and 50 µm.

Fig 3: Increased GFAP expression in astrocytes surrounding tau deposits. Representative images of the hippocampus from female mice treated with vehicle or cisplatin followed by nasal administration of MSC with double immunofluorescence labeling of tau-1 (green) and glial fibrillary acidic protein (GFAP; red) in the hippocampus at 40X (A) and 63X (B). Scale bar in (A) 50 µM and in (B) 25 µM. C High-resolution confocal imaging depicting individual and merged channels of the nuclear marker DAPI (blue), tau-1 (green) and GFAP (red) taken using 100x objective/1.45 NA. Scale bars 25 µm. The region of interest (ROI) in C imaged at higher magnification reveals (D) a single GFAP+ reactive astrocyte (red) with DAPI+ nucleus (blue), with its processes and tau (green) aggregates wrapping each other. Occasionally, tau-1 deposits were detected in the perinuclear region of the astrocyte. Image taken using 100x objective/1.45 NA and 4x scanner zoom. Scale bar 5 µm.