Influence Of NADPH Enzyme Protein Levels Increased Uric Acid Renal Tubular Epithelial Cells On Apoptosis Of Renal Tubular Epithelial Cells

Objective:To observe the effect of different concentration of uric acid on renal tubular epithelial cells in vitroNicotinamide adenine dinucleotidephosphate (NADPH) and reactive oxygen species (ROS),and to explore the possible mechanism of uric acid damage to renal tubular epithelial cells.Methods:Isolated renal tubular epithelial cells and divided them into control group、uric acid group (uric acid group consists of four sub-groups, respectively0.1,0.2,0.4,0.8mmol/L) and NADPH inhibition group, with6wells in each groug;ultraviolet spectrophtometry determines NADPH protein level of renal tubular epithelial cells; Chemiluminescence Method determines (?) formation of renal tubular epithelial cells;TUNEL and agarose gel electrophoresis detects apoptosis of renal tubular epithelial cells.Results:After24h, compared with the control group,NADPH enzyme protein levels and the (?) formation of0.1mmol/L uric acid group only increased slightly, but0.2,0.4,0.8mmol/L uric acid group increased significantly, the difference was Statistically significant (P<0.01); None of the control cells formed distinct DNA apoptotic ladder,0.1mmol/L,0.2mmol/L,0.4mmol/L,0.8mmol/L uric acid groups all formed obvious DNA apoptotic ladder, compared with0.1mmol/L0.2mmol/L uric acid group,0.4mmol/L,0.8mmol/L uric acid group’s DNA apoptotic ladder becomes more apparent. TUNEL results showed that:the apoptosis rates of control group,0.1mmol/L,0.2mmol/L,0.4mmol/L,0.8mmol/L uric acid intervention group were (17.5±1.0)‰,(72.4±12.4)%o,(136.8±13.4)‰,(328.7±32.6)‰,(427.2±51.5)%o, the apoptosis rates of0.1mmol/L,0.2mmol/L,0.4mmol/L,0.8mmol/L uric acid group were significantly higher than those of control group,(P<0.01, n=6),; between the uric acid intervention group, the apoptotic rate increased with the concentration of uric acid increasing; correlation analysis showed that renal tubular epithelial cell apoptosis rate was in highly positive correlation with renal tubular epithelial cell NADPH enzyme protein levels and the (?) formation (y=0.765,0.792; P<0.01).Conclusion:Under the effect of sustained high uric acid,Tubular epithelial cells can activate the intracellular NADPH enzyme protein to express, release (?) and start the cascade of oxidative stress, to cause sustained damage to renal tubular epithelial cells, and lead to the increase of renal tubular cells apoptosis.