Research Paper Volume 13, Issue 14 pp 18051—18093

Beneficial effects of dietary supplementation with green tea catechins and cocoa flavanols on aging-related regressive changes in the mouse neuromuscular system

Effects of GTE- and cocoa-supplemented diets on excitatory cholinergic (VAChT-positive) and glutamatergic (VGluT1 and VGluT2) synaptic inputs to aged spinal MNs. (A–F) Graphs show the average density (number of puncta per 100 μm of MN soma perimeter, A, C, E) and size (in μm2, B, D, F) of the different types of afferent synapses examined; the red dashed line in each graph indicates the mean value of the corresponding afferent synapse density or size found in adult mice [6]. (G1–O2) Representative confocal micrographs of VAChT, VGluT1 and VGluT2 nerve terminals contacting MN cell bodies of animals from control, GTE and cocoa groups, as indicated. Spinal cord sections were immunolabeled for either VAChT, VGluT1 or VGluT2 (green), and counterstained with fluorescent Nissl staining (blue) to visualize MN cell bodies, as indicated in panels. Data in the graphs are expressed as the mean ± SEM, **p p post hoc test); 50-60 MNs were analyzed per animal (number of animals per group: control =3, GTE = 4; and cocoa = 5). Scale bar in O2 = 20 μm (valid for G1–O1).

Figure 5. Effects of GTE- and cocoa-supplemented diets on excitatory cholinergic (VAChT-positive) and glutamatergic (VGluT1 and VGluT2) synaptic inputs to aged spinal MNs. (AF) Graphs show the average density (number of puncta per 100 μm of MN soma perimeter, A, C, E) and size (in μm2, B, D, F) of the different types of afferent synapses examined; the red dashed line in each graph indicates the mean value of the corresponding afferent synapse density or size found in adult mice [6]. (G1O2) Representative confocal micrographs of VAChT, VGluT1 and VGluT2 nerve terminals contacting MN cell bodies of animals from control, GTE and cocoa groups, as indicated. Spinal cord sections were immunolabeled for either VAChT, VGluT1 or VGluT2 (green), and counterstained with fluorescent Nissl staining (blue) to visualize MN cell bodies, as indicated in panels. Data in the graphs are expressed as the mean ± SEM, **p < 0.01 and ***p < 0.001 vs. control (one-way ANOVA, Bonferroni’s post hoc test); 50-60 MNs were analyzed per animal (number of animals per group: control =3, GTE = 4; and cocoa = 5). Scale bar in O2 = 20 μm (valid for G1O1).