Changes in microglia number and Iba1 expression level in the prefrontal cortex of type 1 diabetic mice / 生理学报

ABSTRACT

The aim of the present study was to observe the activation of microglia in the prefrontal cortex of type 1 diabetes mellitus (T1DM) mice, and the expression of the marker genes of the disease-associated microglia (DAM) associated with neurodegenerative diseases. Sixty healthy adult male C57BL/6J mice were randomly divided into two groups, normal control (CON) group and T1DM group. Streptozocin (STZ) was injected intraperitoneally to induce T1DM mice. The spatial learning and memory function of mice was detected by Morris water maze at the 8th week after the successful model establishment. The number and activation of microglia in the prefrontal cortex of mice were detected by immunofluorescence staining and Western blot. Changes in the mRNA level of several DAM molecular markers were detected by RT-FQ-PCR. The results showed that, compared with CON mice, the fasting blood glucose of T1DM mice increased significantly, while the body weight of T1DM mice decreased remarkably (P < 0.05). The escape latency of water maze in T1DM mice was longer than that in CON mice (P < 0.05). Compared with CON group, the Iba1 protein expression and the number of microglia in prefrontal cortex of T1DM group increased significantly (P < 0.05). In addition, the mRNA levels of several DAM markers in prefrontal cortex of T1DM group were increased significantly (P < 0.05). These results suggest that the microglia are activated and transformed to DAM type in the prefrontal cortex of T1DM mice.