Abstract: Objective To investigate the presence of β-amyloid peptide (Aβ) deposition in the cerebellum and the expression of
related miRNAs in the cerebellum of a mouse model of Alzheimer disease. Methods Twelve 12-month-old APPswe/PS△E9
double transgenic mice and 12 wild-type C57 mice were sacrificed and the brain tissues were taken for examination. The right
hemisphere was stained with Congo red to observe the deposition of amyloid substances, and from the left hemisphere, the
hippocampus and the cerebellum were dissected for detecting the expression of miRNA-135a-5p, miRNA-298-5p,
miRNA-466b-3p and miR-669f-3p using real-time PCR. Results Congo red staining revealed the presence of Aβ deposition in
both the hippocampus and the cerebellum of the transgenic mice but not in the control mice. Real-time PCR showed a
significantly lower expression of the 4 miRNAs in the hippocampus in the transgenic mice than in the control mice (P<0.05).
The expression of miRNA-135a-5p, miRNA-298-5p, and miR-669f-3p in the cerebellum was significantly lower in the
transgenic mice than in the control mice (P<0.05). The expression of miRNA-298-5p and miR-669f-3p in the hippocampus was
significantly lower than that in the cerebellum of the transgenic mice (P<0.05). Conclusion Aβ deposition also occurs in the
cerebellum of APPswe/PS △ E9 double transgenic mice, and its formation might be related to the down-regulation of
miRNA-135a-5p, miRNA-298-5p, and miR-669f-3p.