Damaged mitochondria in MSPCs of HSCT-mice. (A) Experimental design for HSCT into lethally irradiated 3-month-old wild-type mice (time point at the end of experiment: 13 months, 13R). Age-matched control group (13A) without HSCT. Analysis of the BM niche in 13-month-old mice (13A and 13R), and Y control group (3 months). Analysis of cultured MSPCs until p4 for analysis with IF assay. (B) Representative confocal microscopy images stained for F-actin (green) and TOMM20 (red) in MSPCs (p4). Image section of a mitochondrion with actin cages. (C) Colocalization pixel of RHOT1 and TOMM20 measured by ImageJ software (left) and representative confocal microscopy images of RHOT1 (green) and TOMM20 (red) counterstained with DAPI (blue, right). (D) Colocalization pixel of MYO6 and TOMM20 measured by ImageJ software. (E) Colocalization pixel of MYO6 and F-actin measured for 3 cells with Imaris software (left) and representative confocal microscopy images for F-actin (stained in green) and MYO6 (yellow) counterstained with DAPI (blue) with additional visualization of colocalization (white) in MSPCs of 13R mice (P4, right). (F) Protein content of OPTN of MSPCs (p4) measured by ImageJ software (the analysis represents 2-3 independent experiments). Scale bars (mitochondria), 0.2μm; scale bars (nucleus), 10 μm. ∗P < .05 (Kruskal-Wallis test: panels C-F). Data are represented as mean ± SD.