Objective: To investigate the expression of STAT3 and PIAS3 in the renal tissues of rats with lupus nephritis.
Methods: The kidneys were harvested from 18-week-old female MRL/lpr mice (lupus nephritis model group) and age-matched female BALB/C mice (normal control group). The expressions of STAT3 and PIAS3 mRNA in the renal tissues were measured by real-time quantitative RT-PCR, and the protein levels of STAT3 and p-STAT3 were examined using Western blotting and immunohistochemistry. The laboratory indices and renal histopathology of the mice were also investigated.
Results: The urinary protein, blood urea nitrogen (BUN) and creatinine levels were significantly higher in MRL/lpr mice than in the control mice (P<0.05). The renal histopathology of MRL/lpr mice was characterized by increased mesangiocapillary proliferation and prominent inflammatory infiltration in the tubulo-interstitium, which were absent in the kidneys of normal control mice. Compared with the control mice, MRL/lpr mice showed significantly increased STAT3 mRNA and p-STAT3 protein levels in the renal tissues (P<0.05) with significantly lowered levels of PIAS3 mRNA (P<0.01). No significant difference was noted in the total STAT3 protein levels between MRL/lpr and control mice.
Conclusion: MRL/lpr mice have significantly increased expressions of STAT3 mRNA and p-STAT3 protein and decreased expression of mRNA PIAS3 in the kidneys compared with BALB/C mice.