This study aims to investigate effects of Piwil2 on autohpagy in a DN rat model. Sixty health SD rats were selected and divided into four group, including normal group, control, DN and Piwil2 therapy group. DN model (DN group) was established by injecting the streptozotocin (50 mg/kg) into rats. Piwil2 therapy group was injected with viral plasmid carrying Piwil2 mRNA to DN rats. The urinary protein concentrations were determined by placing the animals in individual metabolic cages for a timed urine collection every 8 weeks. Blood and soleus muscle samples were collected after animals were sacrificed. Blood glucose was examined by using commercial detection kits. Western blot assay was employed to examine expression of Beclin 1 and LC3 (LC3 I and LC3 II) protein. Results indicated that urinary protein levels were remarkably higher in DN group compared to Normal and Control group (P<0.05). Blood glucose values were also increased in DN group compared to Normal and Control group (P<0.05). Body weights decreased significantly in DN rats compared to Normal group and Control group (P<0.05). Expression of Beclin 1 protein and LC3 proteins was significantly decreased in DN group compared to Normal and Control group (P<0.05). However, Piwil2 transfection could enhance level of Beclin 1 and LC3 protein significantly compared to DN group. In conclusion, the Tiwil 2 mRNA transfection could obviously enhance the autophagy biomarker, including Beclin 1 and LC3 protein, which indicates that the Tiwil 2 treatment has improved the autophagy in diabetic nephropathy rats.
Keywords: Beclin 1; Diabetic nephropathy; LC3 protein; Piwi2 gene; autophagy.