Objective       To investigate the effects of liraglutide on the macrophages infiltration  in kidney of rats with streptozotocin diabetes.        Methods       Forty adult male Sprague-Dawley rats (8 weeks old

weighting 200±25 g) were randomly divided into 3 groups: a normal control group (group NC

n=10)

a diabetes group (group DM

n=15) and a liraglutide treatment group (group LR

n=15). The rats of group DM and group LR received intra-peritoneal injection of low dose streptozotocin to induce an experimental model of type 2 diabetes after high fat and high glucose breeding. The rats of group NC and LR were treated with liraglutide (100 μg/kg twice per day) by hypodermic injection

and the rats of group DM were treated with equal volume normal saline. In 12 weeks after establishment of type 2 diabetes model

we sacrificed the rats and detected 24 h-urinary protein excretory (24 h UPE)

serum creatinine (Scr) and blood urea nitrogen (BUN). The expression of monocyte chemoattractant protein-1 (MCP-1)

nuclear factor-kappa B (NF-κB) and CD68 in the renal tissue was detected by immunohistochemical assay and reverse transcription-polymerase chain reaction (RT-PCR).        Results       Compared with group NC

Scr

BUN and 24 h UPE were significantly increased in the rats of group DM and group LR (P0.01). All of the above indexes were significantly lower in group LR than in group DM (P0.01). MCP-1

NF-κB and CD68 (glomerulus and tubules) were mildly expressed in the renal tissue of group NC

and their expression was significantly enhanced in the renal tissue of group DM and group LR. MCP-1 (2.93±0.27 vs 4.64±0.38)

NF-κB (5.44±1.65 vs 9.76±1.83) and CD68 (4.47±0.66 vs 7.15±0.85; 2.53±0.87 vs 5.65±0.69) levels were significantly lower in group LR than in group DM (P0.01). Correlation analysis showed that the expression of MCP-1

NF-κB and CD68 was positively correlated with 24 h UPE

and the expression of CD68 in renal tissue was positively correlated with the expression of MCP-1 and NF-κB.        Conclusion       Liraglutide can decrease the urine protein and ameliorate renal injury through alleviating macrophage infiltration  by down-regulating the expression of MCP-1

NF-κB and CD68 in renal tissue of type 2 diabetic rats.