Journal: Neurobiology of Sleep and Circadian Rhythms

Article Title: Effects of DNA methylation inhibitors on light-induced circadian clock plasticity

doi: 10.1016/j.nbscr.2025.100134

Figure Lengend Snippet: DNA methylation inhibitor attenuates after-effects on circadian period following long photoperiod entrainment. (A) Representative double-plotted mouse locomotor actograms under different lighting conditions (LD 12:12 cycle, LD 16:8 cycle, constant darkness). Yellow and grey areas indicate light and dark phases, respectively. Black ticks indicate wheel-running behavior patterns. Red asterisks denote onset of RG108 or vehicle infusion into the third ventricle of the brain. (B) Quantification of changes in the endogenous period in constant darkness in control (LD 12:12 cycle) and LD 16:8 (change from LD 12:12 to LD 16:8 cycle) conditions with RG108 or vehicle infusion. (Two-way ANOVA with Sidak's multiple comparisons tests, mean ± SEM, n = 6–7, ns: not significant (p = 0.3639), ∗p = 0.0336). (C) Quantification of the endogenous period during baseline (the first constant darkness) and during the after-effect interval (the second constant darkness) following long photoperiod entrainment in the presence of RG108 or vehicle infusion. (RM two-way ANOVA with Sidak's multiple comparisons tests, mean ± SEM, n = 6, ns: p = 0.3627, ∗∗∗p = 0.0003). (D) Quantification of average daily locomotor activity levels of mice infused with RG108 and its vehicle under light cycles (LD) and in constant darkness (DD). (Two-way ANOVA with Sidak's multiple comparisons tests, mean ± SEM, n = 6–7, individual p-values are shown in the figure).

Article Snippet: 1 μM VIP (Tocris) dissolved in sterile water was applied at CT14 to the culture medium 15 min prior to 200 μM RG108 (dissolved in 0.66 % DMSO) application in the medium.

Techniques: DNA Methylation Assay, Control, Activity Assay

Journal: Neurobiology of Sleep and Circadian Rhythms

Article Title: Effects of DNA methylation inhibitors on light-induced circadian clock plasticity

doi: 10.1016/j.nbscr.2025.100134

Figure Lengend Snippet: DNA methylation mediates after-effects on circadian period of locomotor behavioral rhythms without affecting acute phase delays. (A) Representative wheel-running behavior actograms with brief light exposure (yellow bars) in constant darkness with a drug vehicle (left) or RG108 (right) injection (red asterisk) in the third ventricle. Bars above the actograms indicate the 12h light (yellow) and 12h dark (grey) cycle to which mice were previously entrained before release into constant darkness. Red and blue dashed lines indicate linear regression of locomotor activity onsets before and after light exposure, respectively. The slopes of regression lines are the calculated activity rhythm periods. Yellow arrows denote phase shifts. (B – C) Quantification of phase shifts (B) and period changes (C) following light exposure in vehicle- and RG108-injected mice. (Unpaired t -test, mean ± SEM, n = 5–7, ns: p = 0.9494, ∗∗∗p = 0.0002). (D) Quantification of the endogenous period before and after light exposure (baseline, after-effect) in vehicle- and RG108-injected mice. (RM two-way ANOVA with Sidak's multiple comparisons tests, mean ± SEM, n = 5–7, ns: p > 0.9999, ∗∗∗∗p < 0.0001).

Article Snippet: 1 μM VIP (Tocris) dissolved in sterile water was applied at CT14 to the culture medium 15 min prior to 200 μM RG108 (dissolved in 0.66 % DMSO) application in the medium.

Techniques: DNA Methylation Assay, Injection, Activity Assay

Journal: Neurobiology of Sleep and Circadian Rhythms

Article Title: Effects of DNA methylation inhibitors on light-induced circadian clock plasticity

doi: 10.1016/j.nbscr.2025.100134

Figure Lengend Snippet: DNA methylation mediates VIP-induced after-effects on the ex vivo SCN rhythm period without affecting acute phase delays. (A) Representative double-plotted actograms of PER2LUC bioluminescence rhythms in SCN slices treated with one of combinations of VIP, RG108, and their vehicles. Red and blue lines indicate linear regression of rhythm peaks before and after treatment (green triangles), respectively. Yellow arrows denote phase shifts. (B – C) Quantification of phase shifts (B) and period changes (C) following treatment. (Two-way ANOVA with Sidak's multiple comparisons tests, mean ± SEM, n = 4–6, individual p-values are shown in the figures).

Article Snippet: 1 μM VIP (Tocris) dissolved in sterile water was applied at CT14 to the culture medium 15 min prior to 200 μM RG108 (dissolved in 0.66 % DMSO) application in the medium.

Techniques: DNA Methylation Assay, Ex Vivo

Journal: Neurobiology of Sleep and Circadian Rhythms

Article Title: Effects of DNA methylation inhibitors on light-induced circadian clock plasticity

doi: 10.1016/j.nbscr.2025.100134

Figure Lengend Snippet: Summary of experimental paradigms and findings. (A) Effects of RG108 infusion to the SCN on after-effects of photoperiodic entrainment. (B) Effects of RG108 injection into the SCN on after-effects of discrete light-induced phase shifts. (C) After-effects on SCN PER2LUC rhythms following VIP-induced or optogenetic phase shifts.

Article Snippet: 1 μM VIP (Tocris) dissolved in sterile water was applied at CT14 to the culture medium 15 min prior to 200 μM RG108 (dissolved in 0.66 % DMSO) application in the medium.

Techniques: Injection