Fig. 3. Ndufs4^GT/GT animals showed a more active coping style in the forced swim test (FST) and tail suspension test (TST), they also had less neurogenesis and inflammation in the brain.

a The time the animals spent floating, (b) swimming, and (c) climbing was analyzed during the last 4 min of the FST. Floating was defined as minimal movement of one hind paw so the animal could stay above the water without the animal having a clear swimming direction. d During the TST, the total immobility time was measured. e During the sucrose preference test, mice could choose between two bottles, one bottle containing 1% sucrose and one bottle containing tap water. Their sucrose preference was measured as a percentage of total fluid intake. The dotted line indicates 65%, which has been suggested to be the threshold for anhedonia. f Total sucrose consumption was also measured. The total sucrose consumption was normalized with the body weight of each animal. g After spraying the dorsal coat of the animals with a 10% sucrose solution, the total time spent grooming and (h) average grooming ritual duration was measured. Grooming ritual was defined as the time spent grooming divided by the frequency to start grooming. i The number of doublecortin (DCX) positive neurons was counted as a marker for neurogenesis in the subgranular zone of the dentate gyrus (DG). j The number of DCX-positive neurons in the subventricular zone (SVZ) was also measured. k Representative image from the DCX staining showing the hippocampus with DG and SVZ (arrows). The blue rectangle represents an enlargement from the overview detailing DCX-positive cells in the DG. l As a proxy for inflammation in the brain, the number of Ionized calcium-binding adapter molecule 1 (IBA-1) positive microglia were analyzed in the hippocampus. The number of positive cells was normalized to the surface of the measured area. m Representative image from the IBA-1 staining. The number of IBA-1 cells was only counted in the hippocampus and was corrected for the hippocampal surface, as indicated by the dashed blue line. The blue rectangle represents an enlargement from the overview detailing several IBA-1 positive cells. Scale bars indicate 200 µm. Graphs show average ± SEM, with each black dot representing the result of an individual animal. *p < 0.05, **p < 0.01, ***p < 0.001, and ^#p < 0.07.