Figure 7.

GSNOR decreased CaMKIIα accumulation in aging hippocampal synaptosomal fraction. A, Left, CaMKIIα accumulation level in adult (7 months) and old (22 months) mice hippocampal synaptosomal fraction. Right, Quantitation of CaMKIIα accumulation level normalized by synaptosomal marker SYP (7-month-old, n = 6 mice; 22-month-old, n = 6 mice; two-tailed Student's t test, p = 0.042). B, Top, CaMKIIα accumulation level in primary hippocampal neuron synaptosomal fraction by overexpression of GSNOR. Neuron was transfected by Ctrl, GSNOR, or R115D (GSNOR enzyme activity mutant) lentivirus plasmids. Bottom, Quantitation of CaMKIIα accumulation level normalized by synaptosomal marker SYP: n = 3 experiments; one-way ANOVA, p = 0.009 (ctrl vs GSNOR); p = 0.008 (GSNOR vs R115D). C, Top, CaMKIIα accumulation level in primary hippocampal neuron synaptosomal fraction by downregulation of GSNOR. Neuron was transfected by shGSNOR to downregulated GSNOR protein level. Bottom, Quantitation of CaMKIIα accumulation level normalized by synaptosomal marker SYP (n = 3 experiments; two-tailed Student's t test, p = 0.0071). D, Top, CaMKIIα accumulation level in primary hippocampal neuron synaptosomal fraction by inhibition of GSNOR activity. Neuron was treated by GSNOR inhibitor C3 (33 μm) for 3 h. Bottom, Quantitation of CaMKIIα accumulation level normalized by synaptosomal marker SYP (n = 3 experiments; two-tailed Student's t test, p = 0.036). E, Top, CaMKIIα accumulation level in GSNOR TG mice hippocampal synaptosomal fraction. Bottom, Quantitation of CaMKIIα accumulation level normalized by synaptosomal marker SYP (n = 4 experiments; two-tailed Student's t test, p = 0.0062). F, Top, CaMKIIα accumulation level in GSNOR KO aging mice hippocampal synaptosomal fraction. Bottom, Quantitation of CaMKIIα accumulation level normalized by synaptosomal marker SYP (WT, n = 4 mice; KO, n = 4 mice; two-tailed Student's t test, p = 0.0093). Data are mean ± SEM. *p < 0.05, **p < 0.01.