Figure 2.

Increase of AMP Levels in the Brain Correlates with Neurological Decline

(A) Confocal stacks of 5- and 50-day-old (top and bottom panels, respectively) Attacin-GFP optic lobes of brains immunostained for GFP (green), the glial marker Repo (red), and the neuronal marker Elav (blue). All three markers are shown in the merged image. An increase in GFP staining is observed in the brains of older flies, where GFP co-localizes with both Repo (asterisks) and Elav (arrowheads). The boxed regions show an enlarged image of the optic lobes. Representative images are shown. n = 19 (5 days old) and n = 12 (50 days old). Scale bars, 50 μm.

(B–E) Significant age-dependent upregulation of AMPs in brains was also observed by qPCR (B). This increase was accompanied by neurodegeneration (arrowheads) in 50-day-old flies as observed (C) and quantified (D) in midbrain sections. This was coupled to a reduction in locomotor activity in 50-day-old flies (E).

In all experiments, the fly strain used was w¹¹¹⁸. Values shown are mean ± SEM. Asterisks denote statistically significant differences (^∗p ≤ 0.05, ^∗∗∗p ≤ 0.001. ns, non-significant.