Figure 4. Flies with neuronal overexpression of Ldh show increased neurodegeneration and accelerated decline in locomotor activity rhythms. (A, B) Representative brain section images of 55-day old control elavts>w (A) and elavts>Ldh flies (B) in 25°C (arrows indicate vacuoles). (C, D) Graphs show the average area (C) and number (D) of vacuoles per brain in the brains of elavts>Ldh flies and age-matched controls. Both area and the number of vacuoles were significantly increased in elavts>Ldh (n=36) flies compared to elavts>w (n=38). ****p<0.0001; unpaired t-test with Welch’s correction. (E, F) There was no significant difference in the average area (E) and number (F) of vacuoles in 55-day old repots>Ldh (n=19) brains compared to age-matched repots>w control (n=18). Error bars indicate SEM. (G) Percent of rhythmic elavts>Ldh flies was markedly reduced with age compared to elavts>w controls. (H) Representative actrograms of individual 50-day old elavts>w (rhythmic) and elavts>Ldh (arrhythmic) flies. Gray areas indicate lights off. (I) Percentage of rhythmic repots>Ldh flies were similar to repots>w controls across lifespan. At least 30 flies were tested for each age group and each genotype. (J) Representative actograms of rhythmic 50-day old repots>w and repots>Ldh flies. (K) Total daily activity of 35-day old elavts>Ldh (n=31) flies averaged over six days in constant darkness was significantly reduced relative to control elavts>w (n=30) flies. (L) Total daily activity of 35 days-old repots>Ldh (n=30) flies was also significantly lower than in controls (n=31). Statistical significance by unpaired t-test with Welch’s correction (****p<0.0001). Error bars indicate SEM.