The Accelerated Progression of Atherosclerosis Correlates with Decreased miR-33a and miR-21 and Increased miR-122 and miR-3064-5p in Circulation and the Liver of ApoE-/- Mice with Streptozocin (STZ)-Induced Type 2 Diabetes.

Atherosclerosis is a major risk factor for type 2 diabetes (T2D) mortality. We aim to investigate the changes in miR-21, miR-122, miR-33a and miR-3064-5p in circulation and the liver of ApoE-/- mice with streptozocin (STZ)-induced T2D. Twenty 5-week-old male ApoE-/- mice were randomly assigned to the control (n = 10) and T2D group (n = 10) and intraperitoneally injected with a citrate buffer and streptozotocin (STZ) (40 mg/kg BW) once a day for three consecutive days. The successfully STZ-induced T2D mice (n = 5) and control mice (n = 5) were then fed with a high-fat diet (HFD) for 34 weeks. Compared to the control mice, ApoE-/- mice with STZ-induced T2D had slower (p < 0.05) growth, increased (p < 0.05) total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), decreased (p < 0.05) high-density lipoprotein cholesterol (HDL-C) in serum, reduced (p < 0.05) TC and sterol regulatory element-binding protein-2 (Srebp-2), elevated (p < 0.05) ATP-binding-cassette-transporter-A1 (Abca1) in the liver, aggravated (p < 0.05) atherosclerotic lesions in the aorta, downregulated (p < 0.05) miR-21 and miR-33a, and upregulated (p < 0.05) miR-122 and miR-3064-5p in serum and the liver. In addition, the aortic lesions showed a positive correlation with miR-122 (r = 1.000, p = 0.001) and a negative correlation with miR-21 (r = −1.000, p = 0.001) in ApoE-/- mice with T2D. In conclusion, T2D-accelerated atherosclerosis correlates with a reduction in miR-21 and miR-33a and an elevation in miR-122 and miR-3064-5p in circulation and the liver of ApoE-/- mice.