Effects of a GSK-3β inhibitor on the renal expression levels of RANK, RANKL and NF-κB in a rat model of diabetic nephropathy.

The present study aimed to investigate the effects of glycogen synthase kinase-3β (GSK-3β) on the expression levels of receptor activator of nuclear factor (NF)-κB (RANK), RANK ligand (RANKL) and NF-κB in the renal tissues of rats modeling diabetic nephropathy (DN). The rats were allocated at random into three groups, as follows: Normal control group (NC), the DN model group (DNM group) and the DN model lithium chloride (LiCl) intervention group (DNI group). Urinary proteins were examined by staining with the Coomassie Brilliant Blue dye for 24 h. Histochemical analyses of kidney tissue sections were conducted using hematoxylin and eosin staining, after which the kidney pathology of the rats was observed. In addition, the mRNA and protein expression levels of GSK-3β, RANK, RANKL and NF-κB in the renal tissues were detected using reverse transcription-quantitative polymerase chain reaction and immunohistochemistry, respectively. As compared with the NC group, the level of urinary protein was significantly increased in the DNM group (P<0.05); however, as compared with the DNM Group, the level of urinary protein at 12 weeks was significantly decreased in the DNI group (P<0.05). As compared with the NC group, marked pathological changes were detected, and the mRNA and protein expression levels of GSK-3β, RANK, RANKL and NF-κB were significantly increased, in the renal tissues of the DNM group. Conversely, pathological alterations in the renal tissues were attenuated, and the mRNA and protein expression levels of GSK-3β, RANK, RANKL and NF-κB were significantly decreased (P<0.05), in the DNI group, as compared with the DNM group. The results of the present study suggested that GSK-3β, RANK, RANKL and NF-κB may be crucially involved in the development of DN, and that LiCl may effectively attenuate DN by reducing the expression levels of GSK-3β, RANK, RANKL and NF-κB.