Fig. 1
Gal3 impairs gamma oscillation power and rhythmicity through its carbohydrate-recognition domain (CRD). a Representative power spectra of hippocampal CA3 network activity recorded in control slices (gray), slices pre-incubated for 15 min with 1 µM gal3 (red) and slices co-incubated with 1 µM gal3 + 10 µM TD139 (blue). Inset: Representative power spectra for slices co-incubated with 1 µM gal3 + 10 µM TD139 (gray), co-incubated with 1 µM gal3 + 3 µM TD139 (magenta) or co-incubated with 1 µM gal3 + 1 µM TD139 (green). b Representative example traces of recordings performed in the conditions shown in a. c Summary bar graphs of gamma oscillation power for the conditions shown in a, demonstrating that 10 µM TD139 confers the most effective prevention against gal3-induced decrease of gamma oscillation power (ordinary one-way ANOVA followed by Holm-Sidak’s multiple comparisons test, Additional file 2: Table S1): control (gray, 12.0 ± 2.52 × 10–09 V2, n = 14, N = 5); gal3 (red, 1.60 ± 0.33 × 10–09 V2, n = 13, N = 3); gal3 + 1 µM TD139 (green, 1.88 ± 0.45 × 10–09 V2, n = 10, N = 3); gal3 + 3 µM TD139 (magenta, 3.13 ± 0.53 × 10–09 V2, n = 8, N = 4); gal3 + 10 µM TD139 (blue, 12.3 ± 1.63 × 10–09 V2, n = 14, N = 3). 10 µM TD139 applied alone did not affect gamma oscillations power (light gray, 13.5 ± 3.44 × 10–09 V2, n = 6, N = 2). d Coefficient of rhythmicity calculated from the autocorrelation function as a measure of gamma oscillation quality (see methods). Top: Representative autocorrelation of gamma oscillations recorded in control conditions (gray), in slices pre-incubated with gal3 (red) and slices co-incubated with gal3 + 10 µM TD139 (blue). Bottom: Bar graphs summarizing the Cr calculated for each condition listed in c: control (gray, 0.83 ± 0.01, n = 14, N = 5); gal3 (red, 0.75 ± 0.01, n = 13, N = 3); gal3 + 1 µM TD139 (green, 0.79 ± 0.02, n = 10, N = 3); gal3 + 3 µM TD139 (magenta, 0.8 ± 0.03, n = 8, N = 4); gal3 + 10 µM TD139 (blue, 0.83 ± 0.01, n = 14, N = 3). 10 µM TD139 applied alone did not affect gamma oscillation rhythmicity (light gray, 0.85 ± 0.02, n = 6, N = 2). Statistical testing performed by ordinary one-way ANOVA followed by Holm-Sidak’s multiple comparisons test (Additional file 2: Table S2). e Bar graph summary of gamma oscillation power from slices recorded in control conditions (gray, 10.9 ± 2.04 × 10–09 V2, n = 12, N = 6), slices pre-incubated for 15 min with 1 µM R186S-Gal3 (blue, 10.7 ± 1.56 × 10–09 V2, n = 10, N = 3; P = 0.9265 vs control) and slices pre-incubated for 15 min with 1 µM CRD-Gal3 (red, 2.67 ± 0.69 × 10–09 V2, n = 11, N = 3; P = 0.0022 vs control, P = 0.0029 vs R186S-Gal3), ordinary one-way ANOVA followed by Holm-Sidak’s multiple comparisons test. f Top: Representative autocorrelations of gamma oscillations recorded in the conditions mentioned in e. Bottom: Summary bar graphs of the Cr measured in control conditions (gray, 0.8 ± 0.02, n = 12, N = 6); slices pre-incubated with R186S-Gal3 (blue, 0.76 ± 0.01, n = 10, N = 3; P = 0.1866 vs control), and slices pre-incubated with Gal3-CRD (red, 0.69 ± 0.02, n = 11, N = 3; P = 0.0004 vs control, P = 0.0159 vs R186S-Gal3), ordinary one-way ANOVA followed by Holm-Sidak’s multiple comparisons test. g Representative example traces of recordings performed in the conditions shown in e and f. Data are presented as mean ± SE. Significance levels are shown as *P < 0.05, **P < 0.01, ***P < 0.001. n.s: no significant statistical difference; n: number of slices; N: number of animals