Fig 1: Inhibiting the expression of miR-134-5p reduces the loss of synaptic proteins in vivo and in vitro. Expression of (A) Syn1 and Snap25. Two bands for Syn1 are shown, as the Syn1 gene is subject to alternative splicing, producing two isoforms (synapsin Ia and Ib) which are differentially expressed in animal tissues and cells. *P<0.05, ***P<0.001 vs. the control group; ##P<0.01, ###P<0.001 vs. the VD model group. (B) miR-134-5p antagomir attenuated the loss of the Syn1 protein in the cortex of VD rats. Immunohistochemical staining of paraffin sections was used to observe the expression of Syn1 (n=3/group). ***P<0.001 vs. the control group; ###P<0.001 vs. the VD model group. (C) Foxp2 was determined using western blotting (n=3/group). ***P<0.001 vs. the control group; ###P<0.001 vs. the VD model group. (D) RT-qPCR analysis confirmed that the miRNA mimic and inhibitor transfections were effective and successful (n=3/group). *P<0.05, ***P<0.001 vs. the respective miRNA NC groups. (E) Western blot analysis revealed decreased expression of Syn1 and Snap25 in PC12 cells transfected with miR-134-5p mimic and an increased expression of Syn1 and Snap25 in cells transfected with miR-134-5p inhibitor (n=3/group). *P<0.05, **P<0.01, ***P<0.001 vs. the respective miRNA NC groups. Data were analyzed by one-way ANOVA and are presented as the mean ± standard deviation. Scale bar, 50 µm. VD, vascular dementia; miR, microRNA; m-NC, miRNA mimic negative control; i-NC, miRNA inhibitor negative control; Syn1, synapsin I; Snap25, synaptosome-associated protein 25; Foxp2, forkhead box P2.