Fig 2: Synaptic markers. (A) synaptophysin, PSD-95, and Homer1 prefrontal cortex; (B) synaptophysin, PSD-95, and Homer1 hippocampus; all graphs accompanied by representative blots. Data analysed using an unpaired Student's t-test. mdx = muscular dystrophy mouse model. All values were made relative to the control group (WT). Data expressed as mean ± SEM with n = 12/group. Significance is set to P = 0.05 indicated by *.

Fig 3: Extracellular aSyn hampers long term potentiation in a NMDAR-dependent way.(a) Confocal images of cortico-striatal brain slices incubated without or with 5 µM aSyn, 1 µM TBB, 5 µM aSyn + 1 µM TBB, 1.3 mg/ml chol-MßCD or 5 µM aSyn + 1.3 mg/ml chol-MßCD and immunostained for synaptophysin, synaptotagmin-1 and PSD-95. Scale bar = 150 µm. (b) Statistical analysis of the normalized co-localization index of pre- and post-synaptic proteins in brain slices incubated without or with 5 µM aSyn, 1 µM TBB, 5 µM aSyn + 1 µM TBB, 1.3 mg/ml chol-MßCD or 5 µM aSyn + 1.3 mg/ml chol-MßCD. The co-localization index is PSD-95-synaptophysin: n = 50 from 5 independent experiments. PSD-95-synaptotagmin-1: n = 46 from 5 independent experiments. (c) Representative images of rat hippocampal neurons incubated without or with 5 µM aSyn before and after performing a chemical LTP procedure. Cultures were stained for PSD-95 (green), v-Glut1 (red) and tubulin (blue). Scale bar: 6 µm. (d) Quantification of the mean size of PSD-95 positive clusters. (e) Quantification of the density of PSD-95 puncta. n (fields/condition) = 50 from 3 independent experiments. (f) Representative mEPSC traces of electrophysiological recordings of mEPSCs before and after chemical LTP induction in vehicle or aSyn-treated neurons. (g) Quantification of normalized mEPSC frequency. (h) Quantification of normalized mEPSC amplitude n = 20, 22, 13, 22 from 3 independent experiments. (i) Representative images of rat hippocampal neurons incubated without or with 5 µM aSyn before and after performing forskolin- induced LTP. Cultures were stained as in c. Scale bar: 6 µm. (j) Quantification of the mean size of PSD-95 positive clusters. (k) Quantification of the density of PSD-95 puncta. n (fields/condition) = 50 from 3 independent experiments. Data are expressed as mean ± SEM (b, d, e, g, h, j, k). Statistical significance determined by 1way-ANOVA (b, d, e, j, k), or by t-test (g, h), *p < 0,05, **p < 0.01,***p < 0.001.

Fig 4: Preservation of histological morphology, synaptic proteins expression and glia cells number in the prefrontal cortex or hippocampus of rats subject to bilateral common carotid artery occlusion.(A) Representative H & E staining images of the prefrontal cortex and hippocampus. (B) Representative western blot bands and protein expression percentages of synaptophysin and PSD-95. (C) Representative IHC images of IBA and GFAP in hippocampus. Scale bar: 50 or 1000 µm. Sham group: n = 5; 2VO group: n = 6. Abbreviations: IHC, immunohistochemistry; IBA, ionized calcium binding adapter; GFAP, glial fibrillary acidic protein; PSD-95, postsynaptic density protein-95.

Fig 5: Kir6.2/KATP opener diazoxide elevates levels of synaptic proteins and enlarges neuronal processes in vivo.(A) Immunoblotting analysis of neurite related markers including PSD95, SYP, MAP2, and Tau were detected in midbrain samples from diazoxide-treated and untreated mice. (B) Densitometric analysis of PSD-95, SYP, MAP2, and Tau in A. Data are represented as %. (C) Neuronal morphology in Golgi staining was reflected in a two-dimensional map generated by the Image J software (up). Scale bar is 200 µm. Dendritic spines photographed by oil microscope under 100x magnification (down). (D) Quantitative analysis of the average length of neuronal processes and the level of spine density in C. (E) Movement trace diagrams (red curve) of untreated and diazoxide-treated mice in the OFT. (F) Statistical charts of movement distance and moved speed in the OFT. (G) Analysis of the time consumed in pole test. (H) Analysis of latency time in the rotarod test. (I) Pm20d1 mRNA in the midbrain of untreated and diazoxide-treated mice detected by RT-PCR. (J) Levels of PM20D1 in the midbrain of untreated and diazoxide-treated mice were determined by ELISA kit. (K) Immunoblotting analysis of PM20D1 in midbrain samples from diazoxide-treated and untreated mice. (L) Densitometric analysis of PM20D1 in K. Data are represented as %. (M) ATP contents in the midbrain of untreated and diazoxide-treated mice. Data are analyzed using unpaired Student's t-test. *P < 0.05, **P < 0.01 and ***P < 0.001 vs. CON group. Values are means ± SEM from 10 to 15 mice per group.. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)