Fig. 3: Sirt2 inhibition rescues Fzd1 and Fzd7 epigenome and their transcription in AD. | Molecular Psychiatry

Fig. 3: Sirt2 inhibition rescues Fzd1 and Fzd7 epigenome and their transcription in AD.

From: Epigenetic repression of Wnt receptors in AD: a role for Sirtuin2-induced H4K16ac deacetylation of Frizzled1 and Frizzled7 promoters

Fig. 3

A Scheme representing our cellular AD model, where 15 DIV neuronal cultures were challenged with 100 nM Aβo O/N. B qPCR analyses of Fzds expression upon Sirt2 inhibition by AGK2 in vehicle (Veh) and Aβo treated neurons, showing that AGK2 prevents Fzd1 and Fzd7 downregulation without modulating Fzd5 or Fzd9 mRNA levels. C Representative image and synapse quantification (presynaptic marker vGlut1 (green) on the postsynaptic marker Homer1 (red) and Map2 (blue)) in neuronal cultures treated with the Sirt2 inhibitor AGK2 and challenged with Aβo. Our results show that Sirt2 inhibition prevents Aβo-induced synapse loss. D Scheme representing AGK2 and AK7 treatments in the in vitro AD organotypic model. Hippocampal slices were cultured for 15 DIV and treated with AGK2 for 72 h or with AK7 for 7 days. E qPCR analyses of total mRNA levels from WT and NLGF hippocampal cultures treated with vehicle or AGK2. Our results show that AGK2 treatment rescues Fzd1 and Fzd7 mRNA levels without modulating Fzd5 or Fzd9 mRNA levels. F Scheme representing the epigenetic state of Fzd1 and Fzd7 promoters in AD and how Sirt2 inhibition rescues H4K16ac levels and their mRNA expression. G qPCR results show that AK7 treatment rescues Fzd1 and Fzd7 mRNA levels in AD treated cultures, without modulating Fzd5 or Fzd9 mRNA levels. H ChIP-qPCR showing that AK7 treatment rescues the levels of H4K16ac at Fzd1 and Fzd7 promoters in hippocampal organotypic cultures of NLGF while not changing the levels of this pro-transcriptional histone mark in WT or at Fzd5 and Fzd9 promoter. I) Scheme showing the dosage regime for in vivo inhibition of Sirt2 by intraperitoneal injections of 20 mg/kg of AK7 twice a day for 15 days, from 1.5 to 2 months old animals. J qPCR analyses of total mRNA levels from WT and NLGF hippocampal samples treated with vehicle or AK7. Our results show that AK7 treatment rescues Fzd1 and Fzd7 mRNA levels back to WT in NLGF treated animals and does not show any effect on Fzd5 or Fzd9 mRNA levels. K ChIP-qPCR showing that AK7 treatment rescues the levels of H4K16ac at Fzd1 and Fzd7 promoters in AD while not changes are observed in WT or at Fzd5 and Fzd9 promoters. Data are represented as mean + SEM. Statistical analyses by Two-way ANOVA followed by Games-Howell post hoc in B for all genes analysed; in C by Kruskal-Wallis followed by Dunn’s multiple comparison; in E by Two-way ANOVA followed by Tukey’s post hoc for Fzd1, Fzd5 and Fzd7 and by Kruskal-Wallis followed by Dunn’s multiple comparison for Fzd9; in G Two-way ANOVA followed by Tukey’s post hoc for Fzd1, Fzd7 and Fzd9 and by Kruskal-Wallis followed by Dunn’s multiple comparison for Fzd5; in H Kruskal-Wallis followed by Dunn’s multiple comparison for all Fzd1, Fzd5 and Fzd7 and by Two-way ANOVA followed by Tukey’s post hoc for Fzd9; in G Two-way ANOVA followed by Tukey’s post hoc for Fzd1 and Fzd9 and Kruskal-Wallis followed by Dunn’s multiple comparison for Fzd5 and Fzd7; in K Two-way ANOVA followed by Tukey’s post hoc for Fzd1 and Fzd5 and Two-way ANOVA followed by Games-Howell post hoc for Fzd7 and Fzd9. N is indicated in each bar by the number of symbols. Asterisks indicate *p < 0.05; **p < 0.01; ***p < 0.005.

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