Abstract:

Objective   To investigate the expression of tumor necrosis factor-α induced protein-8 like-2 (TIPE2) and its association with amyloid beta 1-40 deposition in brain tissue of type 2 diabetic GK rat. Methods    GK rats were selected as type 2 diabetic rat model (GK group), and Wistar rats were selected as non-diabetic rat model (Wistar group). Then the spatial distribution of TIPE2 and Aβ1-40 in brain tissue was observed by immunohistochemistry (IHC). The mRNA and protein level of TIPE2 in brain tissue was detected by RT-PCR and Western blot respectively. The expression of Aβ1-40 in brain tissue was quantized by ELISA. Results   TIPE2 was observed in neuroglial cells and small blood vessels of cerebral cortex and subcortical structures in rat brain tissue. Compared to Wistar group, the expression of TIPE2 in brain tissue was significantly higher in GK group (P＜0.05). Aβ1-40 was detected in neurons, neuroglial cells, and brain blood vessel wall of cerebral cortex and hippocampus. Compared to Wistar group, expression of Aβ1-40 in brain tissue was significantly higher in GK group (P＜0.05). The expression of TIPE2 was positively associated with Aβ1-40 level both in Wistar group（r=0.951, P＜0.05） and GK group （r=0.954, P＜0.05）. Conclusion   TIPE2 expression in brain from type 2 diabetic GK group increases significantly than Wistar control group and is positively associated with Aβ1-40 deposition, indicating the role of TIPE2 in diabetic brain damage.

Key words: TIPE2; Beta-amyloid protein; Diabetes mellitus; Inflammation; GK rats